HK1090991B - Image forming apparatus and developer cartridge - Google Patents

Description

Image forming apparatus and developer cartridge

Cross Reference to Related Applications

The present application claims priority from Japanese patent application No.2005-055105, filed on 28/2005. The entire contents of this priority application are incorporated herein by reference.

Technical Field

The present invention relates to an image forming apparatus such as a laser printer, and a developer cartridge detachably mountable to the image forming apparatus.

Background

A developer cartridge for accommodating toner is detachably mounted in a conventional laser printer. Such a laser printer is equipped with a new product detection device to detect whether or not a developer cartridge installed in the laser printer is new, thereby determining the age of the developer cartridge since the new product was detected.

For example, japanese patent application publication No.2000-221781 discloses a developing device in which a sector gear having a concave portion and a convex portion is provided. When a new developing device is mounted in a housing in an electrophotographic image forming apparatus, a projection portion formed on the sector gear is inserted into a new product side sensor, and the new product side sensor is opened. After the developing device is mounted in the housing of the image forming apparatus, the idler gear is driven and rotated. When the idler gear starts to rotate, the sector gear follows the rotation and moves the projecting portion from the new-article-side sensor to the old-article-side sensor. The protruding portion is inserted into the used article side sensor to open the used article side sensor. At the same time, the idler gear reaches the concave portion of the sector gear, and the sector gear stops rotating.

Disclosure of Invention

However, in the new product inspection device described in japanese patent application laid-open No.2000-221781, both the new product side sensor and the old product side sensor are necessary because the projecting portion is inserted into either the new product sensor to detect the new product or the old product sensor to detect the old product. Therefore, this structure increases the cost and complexity of the developing device.

Further, in view of the use cost and frequency, some users are required to freely select an optimum developer cartridge from a plurality of developer cartridges of different price ranges corresponding to different toner amounts.

To meet such a demand, it is necessary to provide a plurality of developer cartridges accommodating different toner amounts. However, the toners contained in these developer cartridges have different agitation properties, and have different degradation rates based on the amount of toner.

In this case, it is not sufficient to merely detect whether the developer cartridge is a new product, because the life of the developer cartridge from the time of detection may differ depending on the amount of toner contained therein. Therefore, the age of the developer cartridge cannot be correctly determined. As a result, the developer cartridge containing a small amount of toner is likely to have reached the end of life before this determination is made, resulting in a decrease in image quality.

In view of the foregoing, it is an object of the present invention to provide an image forming apparatus capable of determining developer cartridge-related information while suppressing an increase in manufacturing cost and avoiding an increase in structural complexity. Another object of the present invention is to provide a developer cartridge detachably mountable to an image forming apparatus.

To achieve the above and other objects, according to one form, the present invention provides an image forming apparatus. The image forming apparatus includes an apparatus body, a driving force generating portion, a developer cartridge, a detecting portion, and an information determining portion. The driving force generating portion is located in the apparatus main body and generates a driving force. The developer cartridge is configured to be detachably mounted in the apparatus main body. The developer cartridge includes a transmission member, a moving portion, and an interference portion. The power transmitting member is configured to be driven by the driving force and to move in a moving direction when the developer cartridge is loaded into the apparatus body. The moving part is arranged on the transmission component and moves in the moving direction together with the transmission component. The interference portion is located downstream of the predetermined detection position with respect to the moving direction, thereby interfering with the moving portion and preventing the moving portion from passing the predetermined detection position for a second time. The detection unit detects passage of the moving unit at a predetermined detection position. The information determining portion determines information relating to the developer cartridge based on a detection result of the detecting portion. The moving part is configured to irreversibly switch from a first position, in which the moving part is allowed to pass through a predetermined detection position, to a second position, in which the moving part is prohibited from passing through the predetermined detection position; and the interference portion obstructs the moving portion so as to cause the moving portion to change from the first position to the second position. The moving portion is supported on the transmission member so as to be pivotable from the first position to the second position.

According to another form, the present invention provides a developer cartridge configured to be detachably mounted to a main body of an image forming apparatus. The developer cartridge includes a transmission member, a moving portion, and an interference portion. The power transmitting member is configured to be driven by the driving force and to move in a moving direction when the developer cartridge is loaded into the apparatus body. The moving portion is provided on the transmission member and moves in the moving direction together with the transmission member. The interference portion is located downstream of the predetermined detection position with respect to the moving direction, thereby interfering with the moving portion and preventing the moving portion from passing the predetermined detection position for a second time. The moving part is configured to irreversibly switch from a first position, in which the moving part is allowed to pass through a predetermined detection position, to a second position, in which the moving part is prohibited from passing through the predetermined detection position; and the interference portion obstructs the moving portion to change the moving portion from the first position to the second position. The moving portion is supported on the transmission member so as to be pivotable from the first position to the second position.

Drawings

Exemplary forms according to the invention will now be described with reference to the accompanying drawings, in which:

FIG. 1 is a side sectional view of a laser printer according to an exemplary form of the present invention;

fig. 2 is a perspective view of the developer cartridge according to the exemplary form, in which a gear cover is mounted;

fig. 3 is a perspective view of the developer cartridge according to this exemplary form, in which the gear cover has been removed;

fig. 4 is a side view of the developer cartridge according to this exemplary form, in which the gear cover has been removed;

fig. 5 is a side sectional view of the developer cartridge (with the gear cover mounted) according to this exemplary form, showing a mechanism for detecting a new product when the developer cartridge is mounted in the main casing;

fig. 6 is a side sectional view of the developer cartridge (with the gear cover mounted) according to the exemplary form, showing a mechanism for detecting a new product when the front moving part is in contact with the transmission mechanism;

fig. 7 is a side sectional view of the developer cartridge (with the gear cover mounted) according to this exemplary form, showing a mechanism for detecting a new product when the front moving member comes into contact with the interfering portion;

fig. 8 is a side sectional view of the developer cartridge (with the gear cover mounted) according to this exemplary form, showing a mechanism for detecting a new product when the rear moving member comes into contact with the transmission mechanism;

fig. 9 is a side sectional view of the developer cartridge (with the gear cover mounted) according to this exemplary form, showing a mechanism for detecting a new product when the rear moving member comes into contact with the interfering portion;

fig. 10 is a side sectional view of the developer cartridge (with the gear cover mounted) according to this exemplary form, showing a mechanism for detecting a new product when the rear moving member has passed the interfering portion;

fig. 11 is a side sectional view of the developer cartridge (with the gear cover mounted) according to this exemplary form, showing the mechanism for detecting a new product when the front moving part completes one revolution and approaches the transmission mechanism;

fig. 12 is a side sectional view of the developer cartridge (mounted with the gear cover) according to this exemplary form, in which the developer cartridge is mounted into the main casing, with the rear moving part omitted;

fig. 13 is a side sectional view of the developer cartridge (with a gear cover mounted) according to another mode, in which the gear cover is fitted into the main casing;

fig. 14 is a side sectional view of the developer cartridge (with the gear cover mounted) according to the other mode, in which the moving member is in contact with the transmission mechanism;

fig. 15 is a side sectional view of the developer cartridge (with the gear cover mounted) according to the another mode, in which the moving member is in contact with the interfering portion and pivotally moves;

fig. 16 is a side view of a developer cartridge according to yet another exemplary form, in which a gear cover has been removed;

fig. 17 is a sectional view of the developer cartridge according to the still another exemplary form, in which a gear cover has been removed;

fig. 18 is a side sectional view of the developer cartridge (mounted with the gear cover) according to the still another form, showing a mechanism for detecting a new product when the developer cartridge is mounted in the main casing;

fig. 19 is a side sectional view of the developer cartridge (with a gear cover mounted) according to the still another form, showing a mechanism for detecting a new product when a front moving member is in contact with a transmission mechanism;

fig. 20 is a side sectional view of the developer cartridge (with the gear cover mounted) according to the still another form, showing a mechanism for detecting a new product when the front moving member is in contact with the interfering portion; and

fig. 21 is a transverse sectional view of the developer cartridge according to the modification of the further form, in which the gear cover has been removed.

Detailed Description

< laser Printer Overall Structure >

An image forming apparatus and a developer cartridge according to an exemplary form of the present invention will be described with reference to fig. 1 to 12. As shown in fig. 1, the laser printer 1 includes a main casing 2, a paper feeding unit 4, and an image forming apparatus 5. The paper feeding unit 4 and the image forming apparatus 5 are housed in the main casing 2. The paper feeding unit 4 feeds the paper 3 to the image forming apparatus 5. The image forming device 5 forms a desired image on the supplied sheet 3.

< Structure of Main case >

An inlet 2A is formed on one side surface (right side in fig. 1) of the main casing 2 for inserting and removing a process cartridge 17 to be described later. The front cover 2B is located on the other side surface of the main casing 2 and can be opened and closed on the inlet 2A. The front cover 2B is rotatably supported by a cover shaft (not shown) inserted through an end of the front cover 2B. When the front cover 2B is closed by the cover shaft, the front cover 2B closes the inlet 2A as shown in fig. 1. When the front cover 2B is opened (rotated downward) about the cover axis, the inlet 2A is opened, and the process cartridge 17 can be loaded into or unloaded from the main casing 2 through the inlet 2A.

In the following description, the side where the front cover 2B is provided is defined as "front", and the opposite side thereof is defined as "rear". < paper feeding unit Structure >

The paper feeding unit 4 is located in the lower half of the main casing 2 and includes a paper feeding tray 6, a paper pressing plate 7, a paper feeding roller 8, a paper feeding pad 9, paper dust removing rollers 10, 11, and a pair of registration rollers 12. The sheet feed tray 6 is detachably mounted with respect to the main casing 2. The paper pressing plate 7 is provided inside the paper feed tray 6 so as to be movable about a pivot. A sheet feed roller 8 and a sheet feed pad 9 are provided on one end of the sheet feed tray 6. Paper dust removing rollers 10, 11 are located downstream of the paper feed roller 8 in the conveying direction of the paper 3. The registration roller 12 is located downstream of the paper dust removing rollers 10, 11 in the conveying direction of the sheet 3.

The platen 7 is used to support a stack of sheets 3. The paper pressing plate 7 is pivotally supported at its end away from the paper feed roller 8 so that the other end of the paper pressing plate 7, i.e., the end close to the paper feed roller 8, is vertically movable. Although not shown in the drawing, the back surface of the paper pressing plate 7 is provided with a spring that presses the paper pressing plate 7 upward. Therefore, the paper pressing plate 7 pivots downward as the number of sheets 3 stacked on the paper pressing plate 7 increases. At this time, the paper pressing plate 7 rotates downward with its end away from the paper feed roller 8 against the urging force of the spring. The sheet feed roller 8 and the sheet feed pad 9 are disposed opposite to each other. A spring 13 is provided under the sheet feeding pad 9 to urge the sheet feeding pad 9 toward the sheet feeding roller 8.

The urging force of the spring below the paper pressing plate 7 urges the uppermost sheet 3 on the paper pressing plate 7 toward the paper feed roller 8, so that the rotation of the paper feed roller 8 causes the uppermost sheet 3 to move between the paper feed roller 8 and the separation pad 13. Thus, the sheets 3 are separated one at a time from a stack of sheets and fed to the paper dust removing rollers 10, 11.

The paper dust removing rollers 10, 11 remove paper dust of the supplied paper 3, and further convey it to the resist roller 12. A pair of registration rollers 12 performs a registration operation on the supplied sheet 3 as required. The sheet 3 is then conveyed to the image forming position. At the image forming position, the photosensitive drum 27 and the transfer roller 30 contact each other. In other words, the image forming position is a transfer position where the visible toner image is transferred from the surface of the photosensitive drum 27 onto the sheet 3 when the sheet 3 passes between the photosensitive drum 27 and the transfer roller 30.

The paper feed unit 4 further includes a multifunction tray 14, a multifunction paper feed roller 15, and a multifunction paper feed pad 25. The multifunction paper feed roller 15 and the multifunction paper feed pad 25 are disposed opposite to each other to feed the sheets 3 stacked on the multifunction tray 14. A spring 26 is provided under the multifunctional sheet feeding pad 25 to push the multifunctional sheet feeding pad 25 upward toward the multifunctional sheet feeding roller 15.

The multi-function paper feed roller 15 rotates to move the sheets 3 one at a time from the stack of sheets on the multi-function tray 14 to a position between the multi-function paper feed pad 25 and the multi-function paper feed roller 15, so that the sheets 3 on the multi-function tray 14 are fed one at a time to the image forming position.

< imaging region Structure >

The image forming section 5 includes a scanning section 16, a process cartridge 17, and a fixing section 18.

< scanning zone Structure >

The scanning area 16 is located at the upper portion of the housing 2, and is provided with a laser emitting area (not shown), a driven rotating polygon mirror 19, lenses 20, 21, and reflecting mirrors 22, 23, 24. The laser emitting area emits a laser beam based on required image data. As shown by a chain line in fig. 1, in the high-speed scanning operation, the laser beam is irradiated onto the surface of the photosensitive drum 27 of the process cartridge 17 after being transmitted or reflected via the mirror 19, the lens 20, the mirrors 22 and 23, the lens 21, and the mirror 24 in this order.

< Structure of Process Cartridge >

The process cartridge 17 is located below the scanner device 16, and includes a process frame 51 detachably loaded in the main casing 2. Within the process frame 51, the process cartridge 17 further includes a developer cartridge 28, a photosensitive drum 27, a corona charger 29, a conductive brush 52, and a transfer roller 30.

The process frame 51 includes an upper frame 53 and a lower frame 54. A sheet conveying path along which the sheet 3 is conveyed is formed between the upper frame 53 and the lower frame 54. The upper frame 53 accommodates the photosensitive drum 27, the charger 29, and the brush 52. The developer cartridge 28 is detachably mounted on the upper frame 53. The lower frame 54 accommodates the transfer roller 30.

The photosensitive drum 27 is cylindrical. The outermost surface of the photosensitive drum 27 is formed of a positively charged photosensitive layer of polycarbonate or the like. The photosensitive drum 27 is supported on the upper frame 53 by a metal drum shaft (not shown) extending in the longitudinal direction of the photosensitive drum 27 and passing through the axial center thereof. The photosensitive drum 27 is rotatable in the process frame 51 about a drum axis. Further, the photosensitive drum 27 is driven to rotate by a driving force input from a motor 59 (see fig. 4).

The charger 29 is supported on the upper frame 53, and is opposed to the photosensitive drum 27 at a position on the upper frame 53. The charger 29 is spaced a predetermined distance from the photosensitive drum 27 to avoid contact therewith. The charger 29 is a positively charged corona charger that generates corona discharge from a discharge wire made of tungsten or the like, thereby forming a uniform positive charge on the surface of the photosensitive drum 27.

The transfer roller 30 is opposed to the photosensitive drum 27 and is in contact therewith from below the photosensitive drum 27. The transfer roller 30 is supported on the lower frame 54 so as to be rotatable in the direction indicated by the arrow (counterclockwise in fig. 1). The transfer roller 30 is an ion conductive transfer roller, and is formed by covering a roller made of a conductive rubber material on a metal roller shaft. During the conveying operation, a transfer bias is applied to the transfer roller 30 by constant-current control. The transfer roller 30 is driven to rotate by a driving force input from a motor 59.

The brush 52 is opposed to the photosensitive drum 27 on the rear side thereof (left side in fig. 1). The brush 52 is fixed to the upper frame 53 such that the movable end of the brush 52 is in contact with the surface of the photosensitive drum 27.

The developer cartridge 28 includes a housing 55, and the developing roller 31, the thickness regulating blade 32, and the supply roller 33 inside the housing 55.

The developer cartridge 28 is detachably mounted on the process frame 51. Thus, when the process cartridge 17 is loaded into the main casing 2, the front cover 2B is opened first, and then the developer cartridge 28 is inserted through the inlet 2A and the developer cartridge 28 is mounted on the process cartridge 17, thereby loading the developer cartridge 28 into the main casing 2.

The housing 55 has a box shape with a rear opening. A partition 56 is provided in the housing 55 at the center in the front-rear direction to partition the internal space of the housing 55. The front area of the casing 55 partitioned by the partition plate 56 serves as the toner containing cartridge 34 for containing toner, and the rear area of the casing 55 partitioned by the partition plate 56 serves as the developing cartridge 57 in which the developing roller 31, the thickness regulating blade 32 and the supply roller 33 are disposed. An opening 37 is formed below the partition plate 56 so that toner passes in the front-rear direction.

The toner containing box 34 contains a positively charged nonmagnetic single-component toner. In the present embodiment, polymerized toner is used as the toner. The polymerized toner is substantially spherical particles and has excellent fluidity. In order to manufacture the polymerized toner, the polymerized monomers are subjected to a copolymerization process such as suspension polymerization. Examples of the polymerizable monomer include a styrene type monomer or an acrylic type monomer. Styrene-type monomers are exemplified by styrene. Examples of acrylic monomers are acrylic acid, alkyl acrylates (C1-C4) and alkyl methacrylates (C1-C4). Since the polymerized toner has excellent fluidity, image development can be reliably performed to form a high-quality image. Materials such as wax and colorant are dispersed in the toner. The colorant may be, for example, carbon black. In addition, an external additive such as silica may be added to the toner to further improve fluidity. The particle size of the toner is about 6 to 10 μm.

The center of the toner containing box 34 is provided with an agitator shaft 35. The agitator shaft 35 is rotatably supported in a side wall 58 of the housing 55 (see fig. 4). The side walls 58 are laterally opposed to each other (a direction perpendicular to the front-rear direction and the vertical direction) but are separated from each other by a predetermined distance. The agitator 36 is provided on the agitator shaft 35. A motor 59 (see fig. 4) generates a driving force input to the agitator rotating shaft 35 to drive the agitator 36 to rotate. The toner in the toner containing box 34 is agitated by driving the agitator 36 to rotate, so that part of the toner is discharged toward the supply roller 33 through the opening 37 formed below the partition 56.

Toner observation windows 38 (see fig. 4) are provided on both side walls 58 of the housing 55 at positions corresponding to the toner containing box 34 for observing the amount of toner remaining in the toner containing box 34. The toner observation windows 38 are opposed to each other in the lateral direction of the toner containing cartridge 34. A light-emitting element (not shown) is provided outside one of the toner observation windows 38 on the main casing 2, and a light-receiving element (not shown) is provided outside the other toner observation window 38 on the main casing 2. Light emitted by the light emitting element enters the toner containing box 34 via the toner observation window 38. When the light passes through the toner containing box 34 and exits from the other toner observation window 38, the light receiving element detects the light as the detection light. Based on the detection result, the laser printer 1 can determine the amount of remaining toner. Further, a cleaner 39 is provided on the agitator rotating shaft 35 to clean the toner observation window 38.

The supply roller 33 is located rearward of the opening 37 and includes a metal supply roller shaft 60 and a sponge roller 61 made of a conductive foam material covering the same. The metal supply roller shaft 60 is rotatably supported at positions corresponding to the developing cartridges 57 on both side walls 58 of the casing 55. The supply roller 33 is driven to rotate by a driving force of a motor 59 to the metal feed roller shaft 60.

The developing roller 31 is located behind the supply roller 33 and is in pressure contact with the supply roller 33 to press both. The developing roller 31 includes a metal developing roller shaft 62 and is formed of a rubber roller 63 made of a conductive rubber material covering the metal developing roller shaft 62. The metallic developing roller shaft 62 is rotatably supported at positions corresponding to the developing cartridges 57 on both side walls 58 of the casing 55. The rubber roller 63 is more specifically formed of an electrically conductive urethane rubber or silicone rubber containing fine carbon particles, the surface of which is coated with a fluorine-containing urethane rubber or silicone rubber. The developing roller 31 is driven to rotate by the driving force of the motor 59 to the metal developing roller shaft 62. A developing bias is applied to the developing roller 31 during the developing operation.

The layer thickness regulating blade 32 is close to the developing roller 31. The layer thickness regulating blade 32 includes a blade made of a metal reed and a pressing member 40 provided at a movable end of the blade. The pressing member 40 has a semicircular sectional view. The pressing member 40 is formed of silicon rubber having an electrical insulation property. The layer thickness regulating blade 32 is supported at a position of the casing 55 close to the developing roller 31. The resilient force of the blade presses the pressing member 40 against the surface of the developing roller 31.

The supply roller 33 supplies the toner discharged through the opening 37 to the developing roller 31 by rotating. At this time, the toner is positively charged by frictional electrification between the supply roller 33 and the developing roller 31. Then, with the rotation of the developing roller 31, the toner supplied onto the developing roller 31 moves between the developing roller 31 and the pressing member 40 of the layer thickness regulating blade 32. This enables the thickness of the toner on the surface of the developing roller 31 to be reduced to a thin layer of uniform thickness.

As the photosensitive drum 27 rotates, the charger 29 charges the photosensitive drum 27 so that the surface thereof has uniform positive electrical properties. Subsequently, the scanner unit 16 irradiates a laser beam on the positively charged surface of the housing 55 in high-speed scanning to form an electrostatic latent image corresponding to an image to be formed on the sheet 3.

Then, one reverse development operation is performed. That is, as the developing roller 31 rotates, the positively charged toner carried on the surface of the developing roller 31 comes into contact with the photosensitive drum 27. At this time, the toner on the developing roller 31 is supplied to the low potential region of the electrostatic latent image on the photosensitive drum 27. As a result, toner is selectively loaded on the photosensitive drum 27, and the electrostatic latent image is visualized as a visible toner image.

Subsequently, as the resist roller 12 conveys the sheet 3 past the transfer position between the photosensitive drum 27 and the transfer roller 30, the toner image loaded on the photosensitive drum 27 is transferred onto the sheet 3 by the transfer bias applied to the transfer roller 30. After the toner image is transferred, the sheet 3 is conveyed to a fixing unit 18.

During the conveying operation, paper dust is deposited on the surface of the photosensitive drum 27 when the photosensitive drum 27 is in contact with the paper 3. Since the photosensitive drum 27 continues to rotate after the transfer operation, the brush 52 removes the toner on the photosensitive drum 27 as the surface of the photosensitive drum 27 and the brush 52 rotate relatively.

In the laser printer 1, after the primary transfer to the paper 3, the toner remaining on the surface of the photosensitive drum 27 is recovered by the developing roller 31. That is, the residual toner is recovered using a so-called detergent-free method. By using a detergent-free method for recovering residual toner, a toner removing device and a waste toner reservoir are eliminated, and the device structure is simplified.

< fixing zone Structure >

As shown in fig. 1, the fixing section 18 is located on the downstream side of the process cartridge 17, and includes a heating roller 41, a pressing roller 42, and a conveying roller 43. The pressing roller 42 presses the heating roller 41. The conveying roller 43 is disposed on the downstream side of the heating roller 41 and the pressing roller 42.

The heating roller 41 includes a metal pipe and a halogen lamp therein. The halogen lamp heats the metal pipe so that the toner transferred onto the paper 3 is thermally fixed on the paper 3 when the paper 3 in the process cartridge 17 passes between the heating roller 41 and the pressing roller 42. Then, the sheet 3 is conveyed to a sheet discharge path 44 by a conveying roller 43, and is discharged onto a sheet discharge tray 46 by a sheet discharge roller 45.

< Structure of double-sided printing mechanism >

The laser printer 1 is further equipped with a reverse conveyance device 47 (duplex printing mechanism) for reversing the sheet 3 that has been printed once and returning the sheet 3 to the image forming device 5, thereby forming images on both sides of the sheet 3. The reverse conveyance device 47 includes a sheet discharge roller 45, a reverse conveyance path 48, a flapper 49, and a plurality of reverse conveyance rollers 50.

The sheet discharging roller 45 is a pair of rollers that can rotate in the forward or reverse direction. The sheet discharging roller 45 rotates forward to discharge the sheet 3 to the sheet discharging tray 46, and rotates backward when the sheet is reversed.

The reverse conveyance roller 50 is located below the image forming apparatus 5. The reverse conveyance path 48 extends vertically between the sheet discharge roller 45 and the reverse conveyance roller 50. The upstream end of the reverse conveyance path 48 is close to the discharge roller 45, and the downstream end thereof is close to the reverse conveyance roller 50, so that the sheet 3 can be conveyed downward from the discharge roller 45 to the reverse conveyance roller 50.

The flapper 49 is swingably provided at the intersection between the sheet discharge path 44 and the reverse conveyance path 48. The flapper 49 is selectively swingable between the direction shown by the broken lines and the direction shown by the solid lines in fig. 1 by energizing or de-energizing an electromagnetic coil (not shown). The direction shown by the solid line in fig. 1 is a direction in which the sheet 3 for single-sided printing is conveyed to the discharge rollers 45. The direction shown by the broken line in fig. 1 is a direction in which the sheet is conveyed from the sheet discharge roller 45 into the reverse conveyance path 48, and is not a direction of being reversed into the sheet discharge path 44.

The reverse conveyance roller 50 is horizontally positioned above the sheet feed tray 6. The pair of reverse conveyance rollers 50 farthest upstream is near the rear end of the reverse conveyance path 48. The pair of reverse transport rollers 50 furthest downstream is located below the calibration roller 12.

When forming images on both sides of the sheet 3, the reverse conveyance device 47 operates in the following manner. The sheet 3 on which an image has been formed on one side is conveyed by the conveying roller 43 from the sheet discharge path 44 to the sheet discharge roller 45. The sheet discharging roller 45 rotates forward with the sheet 3 sandwiched therebetween until almost all of the sheet 3 is fed out from the laser printer 1 above the sheet discharging tray 46. Once the end of the sheet 3 is positioned between the discharge rollers 45, the discharge rollers 45 stop rotating in the forward direction. Then, the flapper 49 switches the conveying direction of the sheet 3 toward the reverse conveying path 48, and at the same time, drives the discharge roller 45 to rotate in the reverse direction. As a result, the sheet 3 is conveyed into the reverse conveyance path 48. Once the sheet 3 is conveyed to the reverse conveyance path 48, the flapper 49 returns to its original position. That is, the flapper 49 is switched back to a position to convey the sheet from the conveying roller 43 to the sheet discharging roller 45.

Then, the inverted sheet 3 is conveyed through the reverse conveyance path 48 to the reverse conveyance roller 50, and then from the reverse conveyance roller 50 to the resist roller 12. The registration roller 12 registers the leading edge of the sheet 3. Then, the sheet 3 is carried to the image forming position. At this time, from the formation of an image on the sheet 3, the upper and lower surfaces of the sheet 3 are reversed, so that an image can be formed on the other surface. Thus, images are formed on both sides of the sheet 3.

A paper discharge sensor 64 is provided along the paper discharge path 44 upstream of the paper discharge rollers 45. The sheet discharge sensor 64 is rotated about its axis every time the sheet 3 passes through the sheet discharge sensor 64 in the sheet discharge direction of the sheet discharge path 44. A CPU100 (see fig. 4) located in the main casing 2 counts the number of rotations of the discharged paper sensor 64 and stores a number of guided sheets.

In the laser printer 1 having such a structure, the CPU100 decides whether or not the developer cartridge 28 mounted in the main casing 2 is a new product, and when it is deemed to be brand new, determines the maximum number of sheets that can be printed by the developer cartridge 28, which will be described later. The CPU100 compares the actual number of printed sheets since the installation of a new developer cartridge 28 with the maximum number of sheets that the developer cartridge 28 can print, and issues a toner-out warning when the actual number of printed sheets approaches the number of printable sheets.

< Structure for inspecting New developer Cartridge according to exemplary form >

Fig. 2 is a perspective view of the developer cartridge with the gear cover mounted according to this exemplary form. Fig. 3 is a perspective view of the developer cartridge with the gear cover removed according to this exemplary form. Fig. 4 is a side view of the developer cartridge with the gear cover removed according to this exemplary form. Fig. 5 to 11 are side sectional views of the gear cover-mounted developer cartridge according to this exemplary form, showing a mechanism for detecting a new product.

As shown in fig. 4, the developer cartridge 28 includes a gear mechanism 65 for rotating the agitator rotating shaft 35 of the agitator 36, the metal supply roller shaft 60 of the supply roller 33, and the metal developing roller shaft 62 of the developing roller 31, and a gear cover 66 for covering the gear mechanism 65, as shown in fig. 2.

The gear mechanism 65 is provided on one side wall of the housing 55 constituting the developer cartridge 28. The gear mechanism 65 includes an input gear 67, a supply roller transmission gear 68, a developer roller transmission gear 69, an intermediate gear 70, and an agitator transmission gear 71.

The input gear 67 is located between the metallic developing roller shaft 62 and the agitator shaft 35 and is rotatably supported on an input gear support shaft 72 projecting laterally outward of the one side wall 58. When the developer cartridge 28 is mounted in the main casing 2, a coupling receiving portion 73 is provided at the shaft center of the input gear 67 to input the driving force from the motor 59 provided in the main casing 2.

A feed roller transfer gear 68 is provided at the shaft end of the metal feed roller shaft 60 below the input gear 67 so as to mesh with the input gear 67. The feed roller drive gear 68 cannot rotate about the metal feed roller shaft 60.

The developer roller transmission gear 69 is provided at the shaft end of the metallic developer roller shaft 62 diagonally rearward and downward of the input gear 67 so as to mesh with the input gear 67. The developer roller transmission gear 69 cannot rotate with the metallic developer roller shaft 62.

The idler gear 70 is rotatably supported on an idler gear support shaft 74 in front of the input gear 67. The idler gear support shaft 74 projects laterally outward of one side wall 58. The intermediate gear 70 is a two-stage gear, and is integrally formed with external teeth 75 meshing with the input gear 67 and internal teeth 76 meshing with the agitator drive gear 71.

The agitator drive gear 71 is disposed at the shaft end of the agitator rotating shaft 35 diagonally forward and downward of the intermediate gear 70. The agitator drive gear 71 cannot rotate about the agitator shaft 35.

When the developer cartridge 28 is mounted in the main casing 2, the motor 59 is coupled with the coupling receiving portion 73 in the developer cartridge 28. Therefore, the input gear 67 starts to rotate when the motor 59 is driven. When the input gear 67 rotates, the supply roller transmission gear 68, the developer roller transmission gear 69, and the intermediate gear 70, which are directly coupled to the input gear 67, and the agitator transmission gear 71, which is coupled to the input gear 67 through the intermediate gear 70, rotate therewith.

The intermediate gear 70 is formed with a cylindrical portion 77 that projects laterally beyond the end surface of the external teeth 75 on the side opposite the internal teeth 76. Two moving members 78 are attached to the end surface of the cylindrical portion 77 on the side opposite to the external teeth 75. Each moving member 78 is substantially rod-shaped and has a base end and a tip end. The base end of each moving member 78 is pivotally supported on a pivot shaft 79 projecting laterally beyond the end surface of the cylindrical portion 77 on the side opposite the external teeth 75. The tip of each moving member 78 extends outward in the radial direction of the intermediate gear support shaft 74. Two pivot shafts 79 supporting the two moving members 78 are provided on the end surface of the cylindrical portion 77 at an interval of 90 degrees with respect to the idler gear supporting shaft 74.

The moving member 78 can pass through the detection position (passing position) described later without being obstructed by the contact pawl 86 (described later), even if the moving member 78 comes into contact with the contact pawl 86 at the detection position. The moving member 78 is coupled to the pivot shaft 79 with an appropriate frictional force so as to allow the moving member 78 to pivot when contacting a hindrance 94 (described below).

The number of the moving members 78 corresponds to information on the amount of toner contained in the toner containing cartridge 34 when a new developer cartridge 28 is used. In other words, the number of the moving members 78 corresponds to the maximum number of sheets 3 on which an image can be formed with respect to the amount of toner accommodated in the toner accommodating box 34 (hereinafter referred to as the maximum printable sheet count).

More specifically, when two moving members 78 as shown in fig. 3 and 4 are provided, the maximum printable number of sheets corresponding to the number of moving members 78 is 6000. When only one moving member 78 is provided, the maximum printable sheet count corresponding to the number of moving members 78 is 3000.

As shown in fig. 2, a gear cover 66 is mounted on one side wall 58 of the developer cartridge 28 to cover the gear mechanism 65. An opening 80 is formed at a rear side of the gear cover 66 to expose the coupling receiving portion 73. Further, an intermediate gear cover 92 is formed on the front side of the gear cover 66 to cover the intermediate gear 70.

The intermediate gear cover 92 is integrally provided with: a substantially cylindrical outer peripheral wall 92A projecting laterally beyond the gear cover 66 for accommodating the intermediate gear 70; and an end wall 92B for covering an outer end face of the outer peripheral wall 92A in the latitudinal direction. The detection window 93 is an opening formed in the rear portion of the intermediate gear cover 92 in the circumferential direction of the outer peripheral wall 92A. The detection window 93 exposes the tip of the moving member 78 that moves circumferentially as the intermediate gear 70 rotates.

As shown in fig. 5, the interference portion 94 is formed on the lower edge of the detection window 93 and extends rearward into the idler gear cover 92. The interference portion 94 is located downstream of the detection position with respect to the moving direction of the moving member 78.

The main casing 2 is provided with an information detection mechanism 81 and a CPU 100. The information detection mechanism 81 detects the passage of the moving member 78. The CPU100 determines the information about the developer cartridge 28 based on the number of times the information detecting mechanism 81 checks the moving member 78. More specifically, the CPU100 decides whether the mounted developer cartridge 28 is new, and determines the maximum printable number of sheets of paper of the developer cartridge 28 when the developer cartridge 28 is new, as described above.

When the developer cartridge 28 is mounted in the main casing 2, as shown in fig. 4, the information detecting mechanism 81 is located on an inner wall (not shown) of the main casing 2 laterally outside the developer cartridge 28. The information detection mechanism 81 includes an actuator 82 and an optical sensor 83.

The actuator 82 is pivotally supported on a pivot 84 projecting laterally inwardly on the inner surface of the main housing 2. The actuator 82 is integrally provided with: a cylindrical insertion portion 85 into which the pivot 84 is inserted, contact serrations 86 extending forward from the cylindrical insertion portion 85 as contact portions, and a light blocking portion 87 extending rearward from the cylindrical insertion portion 85.

As shown in fig. 4, the contact pawl 86 is slightly inclined downward, and the light blocking portion 87 extends substantially in the horizontal direction. The thickness of the light blocking portion 87 in the vertical direction is sufficient to block the detection light emitted by the optical sensor 83.

The spring engaging portion 88 is formed at the midpoint in the longitudinal direction on the light blocking portion 87. One end of the tension spring 89 is engaged with the spring engaging portion 88. A tension spring 89 extends downward from the spring engaging portion 88, and the other end thereof is fixed to the inner surface of the main casing 2 (not shown).

A protruding stopper 90 is formed on the outer surface of the cylindrical insertion portion 85 to protrude radially outward from the top side of the cylindrical insertion portion 85. A stopper contact part 91 is formed on the main casing 2 near the rear side of the protruding stopper 90 and contacts therewith. As shown in fig. 4, the blocking portion 87 of the actuator 82 is continuously pushed down by the tension spring 89. The thrust force is restricted by the protruding stopper 90 contacting the stopper contact portion 91. In this state, the actuator 82 is held such that the light blocking portion 87 extends substantially in the horizontal direction, and the contact pawl 86 is slightly inclined downward from the front side. In this state, the contact pawl 86 of the actuator 82 is located at the detection position where the information detection mechanism 81 detects the passage of the moving member 78, that is, the position where the moving member 78 passes through the information detection mechanism 81.

As will be described later, when the moving member 78 contacts the contact pawl 86 at the detection position, the contact pawl 86 of the contact actuator 82 is pressed downward. Therefore, around the cylindrical insertion portion 85 in the direction of the urging force against the tension spring 89, the light blocking portion 87 rotates upward, and the contact pawl 86 rotates downward (see fig. 6 and 8). As a result, the protruding stopper 90 is separated from the stopper contact portion 91. Subsequently, when the contact between the moving member 78 and the contact pawl 86 is broken, the urging force of the tension spring 89 causes the light blocking portion 87 to rotate downward by the cylindrical insertion portion 85 and the contact pawl 86 to rotate upward by the cylindrical insertion portion 85 until the projection stopper 90 contacts the stopper contact portion 91 (see fig. 7 and 9).

Although not shown in the drawings, the optical sensor 83 is provided on a base member having a substantially U-shape in plan view and opened at one end so that a light emitting element and a light receiving element of the optical sensor 83 are opposed to each other at a space. The optical sensor 83 is disposed such that the light blocking portion 87 of the actuator 82 is interposed between the base members. More specifically, as described above (see fig. 6 and 8), the optical sensor 83 is provided as: when the actuator 82 is in its normal state (see fig. 5), the light blocking portion 87 blocks the probe light emitted from the light emitting element toward the light receiving element; and when the moving member 78 contacts the contact pawl 86 and causes the light blocking portion 87 to rotate upward, the probe light emitted from the light emitting element toward the light receiving element is received by the light receiving element.

< operation to inspect a New developer Cartridge according to this exemplary form >

A method of determining whether the developer cartridge 28 mounted in the main casing is new or old, and determining the maximum printable sheet count of the developer cartridge 28 will be described below.

In this method, the front cover 2B is opened, and the process cartridge 17 containing a new developer cartridge is inserted into the main casing 2 from the inlet 2A. Alternatively, the front cover 2B is opened, and a new developer cartridge 28 is inserted from the inlet 2A into the process cartridge 17 already mounted on the main casing 2.

As shown in fig. 5, two moving members 78 are provided on the intermediate gear 70 in the developer cartridge 28. When the developer cartridge 28 is new, as shown in fig. 5, the moving member 78 is provided to extend in the radial direction of the idler gear supporting shaft 74 (first position). Meanwhile, the moving member 78 is located upstream of the detection position. Therefore, when the developer cartridge 28 is mounted in the main casing 2, the moving member 78 does not contact the contact serrations 86 of the actuator 82, and the actuator 82 is in a normal state in which the light blocking portion 87 blocks the detection light of the optical sensor 83.

Further, when the developer cartridge 28 is mounted in the main casing 2, a coupling insertion portion (not shown) for transmitting a driving force from the motor 59 in the main casing 2 is inserted into the coupling receiving portion 73 of the input gear 67 in the developer cartridge 28. As a result, the driving force from the motor 59 drives the input gear 67, the supply roller transmission gear 68, the developer roller transmission gear 69, the intermediate gear 70, and the agitator transmission gear 71 of the gear mechanism 65.

Then, when the developer cartridge 28 is loaded into the main casing 2, the CPU100 starts a warm-up process, and performs an operation in which the agitator 36 idles.

In the idle rotation operation, the CPU100 drives the motor 59 provided in the main casing 2. The driving force of the motor 59 is input from the coupling insertion portion to the input gear 67 of the developer cartridge 28 through the coupling receiving portion 73, and drives the input gear 67 to rotate. At this time, the feed roller transmission gear 68 meshed with the input gear 67 is driven to rotate. The rotation of the metal supply roller shaft 60 sequentially rotates the supply roller 33. Further, the developer roller transmission gear 697, which meshes with the input gear 67, is driven to rotate, and the rotation of the metallic developer roller shaft 62 in turn rotates the developer roller 31. Further, the intermediate gear 70 meshing with the input gear 67 is driven to rotate via the external teeth 75, causing the internal teeth 76 integrally formed with the external teeth 75 to also rotate. When the internal teeth 76 of the intermediate gear 70 rotate, the agitator drive gear 71 that meshes with the internal teeth 76 is driven to rotate. Rotation of the agitator shaft 35 rotates the agitator 36, which agitates the toner in the toner containing box 34 and generates a flow of the toner.

When the intermediate gear 70 is driven to rotate, the moving member 78 mounted on the cylindrical portion 77 moves in the circumferential direction a (counterclockwise direction in fig. 5). At this time, as shown in fig. 6, the tip end of the (front) guide moving member 78 comes into contact with the contact pawl 86 of the actuator 82 at the detection position in the downward movement. The actuator 82 rotates around the cylindrical insertion portion 85 in the direction against the urging force of the tension spring 89, so that the contact pawl 86 moves downward and the light blocking portion 87 moves upward, as indicated by arrow B in fig. 6. Thus, the light receiving element receives the detection light from the optical sensor 83, which was blocked by the light blocking portion 87 when the actuator 82 was in the normal state. The optical sensor 83 sends a reception signal to the CPU100 according to the received light. The CPU100 recognizes the received signal as the first received signal and resets the number of printed sheets detected by the sheet discharge sensor 64.

As the intermediate gear 70 is further driven to rotate, the tip end of the pilot moving member 78 further presses the contact pawl 86 while sliding along the contact pawl 86, and then passes through and separates from the contact pawl 86, as shown in fig. 7. Therefore, when the contact point between the moving member 78 and the contact pawl 86 is removed, the urging force of the tension spring 89 causes the actuator 82 to rotate about the cylindrical insertion portion 85 in the direction opposite to the arrow B in fig. 6, so that the contact pawl 86 moves upward and the light blocking portion 87 moves downward until the actuator 82 returns to its normal state. At this time, the light blocking section 87 once again blocks the detection light of the optical sensor 83 that has been received by the light receiving element.

When the intermediate gear 70 is further driven to rotate, the tip end of the (rear) trailing moving member 78 comes into contact with the contact pawl 86 of the actuator 82 at the detection position in the downward movement, as shown in fig. 8. The actuator 82 rotates around the cylindrical insertion portion 85 in the direction against the urging force of the tension spring 89, so that the contact pawl 86 moves downward and the light blocking portion 87 moves upward, as indicated by arrow B in fig. 6. Thus, the light receiving element receives the detection light from the optical sensor 83, which was blocked by the light blocking portion 87 when the actuator 82 was in the normal state. The optical sensor 83 sends a reception signal to the CPU100 according to the received light. The CPU100 recognizes the received signal as a second received signal.

As the intermediate gear 70 is further driven to rotate, the tip end of the tail (rear) moving member 78 further presses the contact pawl 86 while sliding along the contact pawl 86, and then passes through and separates from the contact pawl 86, as shown in fig. 9. Therefore, when the contact point between the moving member 78 and the contact pawl 86 is removed, the urging force of the tension spring 89 causes the actuator 82 to rotate about the cylindrical insertion portion 85 in the direction opposite to the arrow B in fig. 6, so that the contact pawl 86 moves upward and the light blocking portion 87 moves downward until the actuator 82 returns to its normal state. At this time, the light blocking section 87 once again blocks the detection light of the optical sensor 83 that has been received by the light receiving element.

As shown in fig. 7 and 9, after each moving member 78 passes the detection position, the tip of each member comes into contact with the interference portion 94. As the intermediate gear 70 is driven to rotate further from this position, each of the moving members 78 is forced to rotate about the respective pivot shaft 79 while sliding against the interference portion 94 until reaching a position (second position) where the tip end of the moving member 78 does not protrude from the outer surface of the cylindrical portion 77. Thus, the moving member 78 is irreversibly switched (shifted) from the first position to the second position by being subjected to a frictional force between the moving member 78 and the pivot shaft 79 that pivotably supports the moving member 78.

After the moving member 78 is rotated to the second position, as the intermediate gear 70 continues to rotate, the tip of the moving member 78 no longer passes the detection position. Thus, the interference portion 94 again prevents the moving member 78 from passing the detection position. Therefore, after the CPU100 recognizes the second received signal, the actuator 82 no longer rotates with the rotation of the intermediate gear 70, and the light receiving element no longer receives the detection light from the optical sensor 83.

During this idle operation, the CPU100 determines whether the developer cartridge 28 is a new product according to whether the received signal is input from the optical sensor 83, and determines the maximum printable sheet count of the developer cartridge 28 according to the number of received signals input from the optical sensor 83. More specifically, in the example shown in fig. 5 to 11, the CPU100 determines that the developer cartridge 28 is new based on recognizing the first received signal, as described above.

Further, the CPU100 associates the number of received signals input with information on the maximum printable sheet count. Specifically, for example, when two received signals are input, the CPU100 associates this number as a maximum of 6000 sheets to be printed. When a single received signal is input, the CPU100 associates this number as a maximum of 3000 sheets to be printed.

In the above examples of fig. 5-11, the CPU100 identifies the first and second received signals within a predetermined duration before the end of the idle operation. After recognizing the second received signal, the CPU100 determines the maximum printable number of sheets of the new developer cartridge 28 to be 6000.

Thus, when the developer cartridge 28 in the example of fig. 5 to 11 is loaded into the main casing 2, the CPU100 determines that the developer cartridge 28 is new, and determines that the maximum printable sheets of the developer cartridge 28 is 6000. After the developer cartridge 28 is mounted, the CPU100 calculates the actual number of printed sheets detected by the sheet discharge sensor 64, and issues a toner-out warning (not shown) through a control panel or the like when the actual number of printed sheets approaches or reaches 6000.

However, when one of the two moving members 78 (the trailing moving member 78) is omitted from the example of fig. 5 to 11 so that the developer cartridge 28 is equipped with only one moving member 78 (see fig. 12), the CPU100 recognizes only one receipt signal when the developer cartridge 28 is mounted. Therefore, the CPU100 determines that the developer cartridge 28 is new and that the maximum printable number of sheets of the developer cartridge 28 is 3000. After the developer cartridge 28 is mounted, the CPU100 calculates the actual number of printed sheets detected by the sheet discharge sensor 64, and issues a toner-out warning (not shown) through a control panel or the like when the actual number of printed sheets approaches or reaches 3000.

However, if a new developer cartridge 28 loaded in the main casing 2 is temporarily removed and then reloaded, the CPU100 starts the warm-up process and performs the idle rotation operation to rotate the agitator 36. At this time, as described above, the moving member 78 does not pass the detection position, and the optical sensor 83 does not input the received signal into the CPU 100. Therefore, the CPU100 determines that the developer cartridge 28 is old because no signal is received during idling.

Here, the developer cartridge 28 according to the present invention is not limited to the structure having one or two moving members 78, but three or more moving members 78 may be provided. In this case, the CPU100 can determine the information of the developer cartridges 28 corresponding to the number of the moving members 78.

< Effect to test New developer Cartridge according to this exemplary form >

In the laser printer 1 as described above, when the developer cartridge 28 is loaded into the main casing 2, the motor 59 drives the intermediate gear 70. When the intermediate gear 70 is driven, the moving member 78 moves and passes the detection position. The information detection mechanism 81 detects the passage of the moving member 78. The CPU100 determines the information about the developer cartridge 28 (whether the developer cartridge 28 is new, and if new, the maximum printable sheet count of the developer cartridge 28) based on the detection result of the information detecting mechanism 81 (whether a signal is input and the number of input received signals). Therefore, the laser printer 1 capable of determining the relevant information of the developer cartridge 28 can be manufactured at a low manufacturing cost by a simple structure equipped with the single information detection mechanism 81.

After the information detection mechanism 81 checks the passage of the moving member 78, the interference portion 94 blocks the moving member 78 to prevent the moving member 78 from passing through the detection position. Therefore, when the developer cartridge 28 is loaded into the main casing 2 and the motor 59 drives the intermediate gear 70, the laser printer 1 of the present exemplary form can easily and reliably determine whether the developer cartridge 28 is new based on the detection of the passage of the moving member 78 by the information detecting mechanism 81. Thus, the laser printer 1 can determine the age of the developer cartridge 28 from when it is determined to be new.

Since the information detection mechanism 81 gives way to the moving member 78 when detecting the passage, there is a possibility that a plurality of moving members 78 are provided and the plurality of moving members 78 pass through the detection position. As a result, the CPU100 can determine the information of the plurality of developer cartridges 28 based on the number of the moving members 78 detected by the information detecting mechanism 81. If the information relating to the developer cartridge 28 includes the maximum number of sheets printable in accordance with the amount of toner accommodated in the developer cartridge 28, it is possible to accurately determine the age of the developer cartridge 28 loaded into the main casing 2 and appropriately replace the developer cartridge 28, even when developer cartridges 28 of different toner amounts are used.

After the information detection mechanism 81 detects the passage of the moving member 78 located at the first position, the interference portion 94 blocks the moving member 78 and irreversibly shifts (rotates) the moving member 78 to the second position, thereby preventing the information detection mechanism 81 from detecting the passage of the moving member 78 again. Thus, the laser printer 1 capable of determining the information relating to the developer cartridge 28 can be manufactured at a low cost by a simple structure having the moving member 78 that irreversibly moves from the first position to the second position.

By providing the moving member 78 on the intermediate gear 70 in the developer cartridge 28, it is not necessary to provide a new transmission member for transmitting the driving force of the motor 59 to the moving member 78. Thus, it is possible to manufacture a more compact device while avoiding an increase in manufacturing cost and structural complexity.

By providing the moving member 78 on the intermediate gear 70, which is located at a position more freely than the input gear 67 and the agitator drive gear 71, the moving member 78 can be located at a position more easily detected by the information detecting mechanism 81.

Further, the position of contact between the moving member 78 provided on the intermediate gear 70 and the interference portion 94 can be determined by providing the interference portion 94 on the gear cover 66 and covering the intermediate gear 70 with the gear cover 66. This structure ensures that the interference portion 94 can reliably interfere with the moving member 78.

Since the moving member 78 is disposed to extend in the radial direction of the idler gear supporting shaft 74 when in the first position, it is possible to prevent the developer cartridge 28 from becoming large in the width direction, making the developer cartridge 28 more compact.

Although the moving member 78 contacts the contact pawl 86 of the actuator 82, the moving member 78 is able to pass through the sensing position and then contact the interference portion 94 without being obstructed by the contact pawl 86. Thus, the information detection mechanism 81 can reliably detect the passage of the moving member 78.

< Structure for inspecting New developer Cartridge according to another mode >

Fig. 13 to 15 are side sectional views of a gear housing-mounted developer cartridge according to another form of the invention, in which like parts are designated by like reference numerals to avoid repetitive description.

As shown in fig. 13, the developer cartridge 28 according to this other form has a moving member 178. Unlike the substantially rod-shaped moving member 78 in the exemplary form, the moving member 178 according to this other form is substantially fan-shaped (or fan-like shape) and has an arcuate outer peripheral surface 178A. The developer cartridge 28 includes a single moving member 178 connected to an end surface of the cylindrical portion 77 on the side opposite to the external teeth 75. The base end of the moving member 178 is located on the central angle side where the arc-shaped outer peripheral surface 178A is formed. The moving member 178 is pivotally supported on a pivot shaft 79 at the base end, the pivot shaft 79 projecting laterally beyond a side end face of the cylindrical portion 77 opposite the external teeth 75. The moving member 178 is formed with a tip end of an arc-shaped outer peripheral surface 178A extending radially outward with respect to the idler gear support shaft 74.

The circumferential length of the arcuate peripheral surface 178A serves as information relating to the developer cartridge 28 with respect to the amount of toner contained in the toner containing cartridge 34 when a new developer cartridge 28 is used. Specifically, the arc-shaped outer peripheral surface 178A corresponds to the maximum number of sheets 3 on which an image can be formed with respect to the amount of toner accommodated in the toner accommodating box 34 (hereinafter referred to as the maximum printable sheet count).

More specifically, if the moving member 78 is substantially rod-shaped as shown in fig. 12, such a shape corresponds to information that the maximum printable sheet count is 3000. However, if the moving member 178 is substantially fan-shaped as shown in fig. 13, such a shape corresponds to information that the maximum printable sheet count is 6000.

< operation to inspect a New developer Cartridge according to this other form >

A method of determining whether the developer cartridge 28 mounted in the main casing according to this other form is new or old, and determining the maximum printable sheet count of the developer cartridge 28 will be described below.

In this method, the front cover 2B is opened, and the process cartridge 17 containing a new developer cartridge is inserted into the main casing 2 from the inlet 2A. Alternatively, the front cover 2B is opened, and a new developer cartridge 28 is inserted from the inlet 2A into the process cartridge 17 already mounted on the main casing 2.

As shown in fig. 13, a single substantially fan-shaped (or fan-like shape) moving member 178 is provided on the intermediate gear 70 in the developer cartridge 28. When the developer cartridge 28 is new, as shown in fig. 13, the moving member 178 is provided to extend in the radial direction of the intermediate gear supporting shaft 74 (first position). Meanwhile, the moving member 178 is located upstream of the detection position. Therefore, when the developer cartridge 28 is loaded into the main casing 2, the moving member 178 does not contact the contact serrations 86 of the actuator 82, and the actuator 82 is in a normal state in which the light blocking portion 87 blocks the detection light of the optical sensor 83.

After the developer cartridge 28 is mounted in the main casing 2, the CPU100 starts the warm-up operation, and performs the idle rotation operation to rotate the agitator 36. During this operational run, the intermediate gear 70 is driven by the motor 59 to rotate together therewith, causing the moving member 178 mounted on the cylindrical portion 77 to move in the circumferential direction C (counterclockwise in fig. 13). At this time, as shown in fig. 14, the tip of the moving member 178 comes into contact with the contact pawl 86 of the actuator 82 at the detection position in the downward movement. The actuator 82 rotates around the cylindrical insertion portion 85 in the direction against the urging force of the tension spring 89, so that the contact pawl 86 moves downward and the light blocking portion 87 moves upward, as indicated by an arrow D in fig. 14. Thus, the light receiving element receives the detection light from the optical sensor 83, which was blocked by the light blocking portion 87 when the actuator 82 was in the normal state. The optical sensor 83 sends a reception signal to the CPU100 according to the received light. The CPU100 recognizes the received signal as the first received signal and resets the number of printed sheets detected by the sheet discharge sensor 64.

As the intermediate gear 70 is further driven to rotate, the arcuate outer peripheral surface 178A of the moving member 178 further presses the contact inverted teeth 86 while sliding along the contact inverted teeth 86, and then passes through and separates from the contact inverted teeth 86. Therefore, when the contact point between the moving member 178 and the contact pawl 86 is removed, the urging force of the tension spring 89 causes the actuator 82 to rotate about the cylindrical insertion portion 85 in the direction opposite to the arrow D in fig. 14, so that the contact pawl 86 moves upward and the light blocking portion 87 moves downward until the actuator 82 returns to its normal state. At this time, the light blocking section 87 once again blocks the detection light of the optical sensor 83 that has been received by the light receiving element.

As described in the exemplary form, after the moving member 178 passes the detection position, the tip of the moving member 178 comes into contact with the interference portion 94. As the intermediate gear 70 is further driven to rotate from this position, each moving member 178 is forced to rotate about the respective pivot shaft 79 while sliding against the interference portion 94 until reaching a position (second position) where the arcuate outer peripheral surface 178A of the moving member 178 does not protrude from the outer surface of the cylindrical portion 77, as shown in fig. 15. Thus, the moving member 178 is irreversibly switched (shifted) from the first position to the second position by being subjected to a frictional force between the moving member 178 and the pivot shaft 79 pivotably supporting the moving member 178.

As in the exemplary form, after the moving member 178 rotates into the second position, the tip of the moving member 178 no longer passes the detection position as the intermediate gear 70 continues to rotate. Thus, the interference portion 94 again prevents the moving member 178 from passing the detection position. Therefore, after the CPU100 recognizes the first received signal, the actuator 82 no longer rotates with the rotation of the intermediate gear 70, and the light receiving element no longer receives the detection light from the optical sensor 83.

During this idle operation, the CPU100 determines whether the developer cartridge 28 is a new product according to whether the received signal is input from the optical sensor 83, and determines the maximum printable sheet count of the developer cartridge 28 according to the number of received signals input from the optical sensor 83.

Specifically, in another form of lost motion operation as shown in FIGS. 13-15, the moving member 178 contacts the contact pawl 86, as shown in FIG. 14, and then slides along the contact pawl 86 past the sensing position. Due to the substantially fan shape, the moving member 178 takes longer to pass into contact with the pawl 86. Thus, the optical sensor 83 inputs the received signal to the CPU100 for the longer time period.

However, since the moving member 78 in fig. 12 is substantially rod-shaped, it takes a short time for the moving member 78 to slide over the contact pawl 86 after first contacting the contact pawl 86 in the idle operation. Thus, the optical sensor 83 inputs the received signal to the CPU100 in a short time.

Thus, the CPU100 can determine the maximum printable number of sheets of the developer cartridge 28 according to the input time of the received signal. For example, the CPU100 determines that the maximum printable sheet count is 3000 when the input time is short, and determines that the maximum printable sheet count is 6000 when the input time is long.

Thus, when the developer cartridge 28 in the example of fig. 13 to 15 is loaded into the main casing 2, the CPU100 determines that the developer cartridge 28 is new, and determines that the maximum printable sheets of the developer cartridge 28 is 6000. After the developer cartridge 28 is mounted, the CPU100 calculates the actual number of printed sheets detected by the sheet discharge sensor 64, and issues a toner-out warning (not shown) through a control panel or the like when the actual number of printed sheets approaches or reaches 6000.

However, if a new developer cartridge 28 loaded in the main casing 2 is temporarily removed and then reloaded, the CPU100 starts the warm-up process and performs the idle rotation operation to rotate the agitator 36. At this time, as described above, the moving member 178 does not pass the detection position, and the optical sensor 83 does not input the received signal into the CPU 100. Therefore, the CPU100 determines that the developer cartridge 28 is old because no signal is received during idling.

Here, the developer cartridge 28 according to the present invention is not limited to the structure having one moving member 178, but two or more moving members 178 may be provided.

< Effect to test New developer Cartridge according to this other mode >

In the laser printer 1 as described above, when the developer cartridge 28 is loaded into the main casing 2, the motor 59 drives the intermediate gear 70. When the intermediate gear 70 is driven, the moving member 178 moves and passes the detection position. The information detection mechanism 81 detects the passage of the moving member 178. The CPU100 determines the information about the developer cartridge 28 (whether the developer cartridge 28 is new, and if new, the maximum printable paper duration of the developer cartridge 28) based on the detection result of the information detecting mechanism 81 (whether there is a signal input received and the duration of the signal input). Therefore, the laser printer 1 capable of determining the relevant information of the developer cartridge 28 can be manufactured at a low manufacturing cost by a simple structure equipped with the single information detection mechanism 81.

After the information detection mechanism 81 checks the passage of the moving member 178, the interference portion 94 obstructs the moving member 178 to prevent it from subsequently passing through the detection position. Therefore, when the developer cartridge 28 is mounted in the main casing 2 and the motor 59 drives the intermediate gear 70, the laser printer 1 according to the other form can easily and reliably determine whether the developer cartridge 28 is new based on the detection of the passage of the moving member 178 by the information detecting mechanism 81. Thus, the laser printer 1 can determine the age of the developer cartridge 28 from when it is determined to be new.

Further, by setting the circumference of the arcuate outer peripheral surface 178A of the fan-shaped (circular segment shaped) moving member 178 to correspond to the information (the maximum number of printable sheets) relating to the developer cartridge 28, the CPU100 can determine the information of the plurality of developer cartridges 28 corresponding to the circumferences based on the duration of detection of the moving member 178 by the information detecting mechanism 81.

After the information detection mechanism 81 detects the passage of the moving member 178 located at the first position, the interference portion 94 receives the moving member 178 and irreversibly shifts (rotates) the moving member 178 to the second position, thereby preventing the information detection mechanism 81 from detecting the passage of the moving member 178 again. Thus, the laser printer 1 capable of determining the information relating to the developer cartridge 28 can be manufactured at a lower cost by a simple structure having the moving member 178 that irreversibly turns from the first position to the second position.

By providing the moving member 178 on the intermediate gear 70 in the developer cartridge 28, it is not necessary to provide a new transmission member for transmitting the driving force of the motor 59 to the moving member 178. Thus, it is possible to manufacture a more compact device while avoiding an increase in manufacturing cost and structural complexity.

By providing the moving member 178 on the intermediate gear 70, which is located at a position more freely than the input gear 67 and the agitator drive gear 71, the moving member 178 can be located at a position more easily detected by the information detecting mechanism 81.

Further, the position of contact between the moving member 178 provided on the intermediate gear 70 and the interfering portion 94 may be determined by providing the interfering portion 94 on the gear cover 66 and covering the intermediate gear 70 with the gear cover 66. This structure ensures that the interference portion 94 can reliably interfere with the moving member 178.

Since the moving member 178 is disposed to extend in the radial direction of the idler gear supporting shaft 74 when in the first position, it is possible to prevent the developer cartridge 28 from becoming large in the width direction, making the developer cartridge 28 more compact.

Although the moving member 178 contacts the contact pawl 86 of the actuator 82, the moving member 178 is able to pass through the detection position and then contact the interference portion 94 without being obstructed by the contact pawl 86. Thus, the information detection mechanism 81 can reliably detect the passage of the moving member 178.

< Structure for inspecting New developer Cartridge according to still another form >

Fig. 16 is a side view of the developer cartridge according to still another form, in which a gear cover has been removed. Fig. 17 is a sectional view of the developer cartridge according to the still another form, in which the gear cover has been removed. FIGS. 18 to 20 are side sectional views of the developer cartridge according to this further form with the gear cover removed, showing a structure for detecting a new developer cartridge. In the developer cartridge according to the still another form, the same components as those of the developer cartridge in the above-described exemplary form are given the same numerals to avoid repetitive description.

As shown in fig. 16 and 17, unlike the moving member 78 in the foregoing exemplary form, the moving member 278 is not pivotably supported, but is formed as a protrusion protruding from the outer surface of the cylindrical portion 77. The developer cartridge 28 according to this further form is provided with two moving members 278 that project on the outer surface of the cylindrical portion 77 on the side opposite the external teeth 75 in the radial direction of the idler gear supporting shaft 74. Each moving member 278 has a base end fixed to the outer surface of the cylindrical portion 77 and a tip end extending radially outward along the idler support shaft 74. The bottom portions of the moving members 278 are arranged along the outer surface of the cylindrical portion 77 at intervals such that an angle of 90 ° is formed with the idler gear support shaft 74 as the apex.

The idler gear body 95 integrally has external teeth 75 and internal teeth 76. The cylindrical portion 77 of the idler gear 70 is rotatably coupled to an idler gear body 95 by a mount 96 (fig. 17) and is coaxial with the idler gear support shaft. The end face wall 77A closes the end face of the columnar portion 77 on the side of the idler gear body 95. The concave portion 95A is substantially circular and corresponds to the outer peripheral surface of the cylindrical portion 77, and is formed in the end surface of the idler gear body 95 on the side of the cylindrical portion 77. The end face wall 77A of the cylindrical portion 77 is fitted into the depressed portion 95A. The through hole 77B passes through the center of the end face wall 77A in the thickness direction thereof.

The fixing member 96 includes: a shaft portion 96A, and a head portion 96B formed at one end of the shaft portion 96A and having a larger cross-sectional area perpendicular to the axial direction than the shaft portion 96A. The shaft portion 96A of the fixing piece 96 is inserted through the through hole 77B formed in the end face wall 77A, and is fixedly inserted into the intermediate gear support shaft 74. With this structure, the fixing piece 96 is disposed inside the cylindrical portion 77 and laterally outside the idler gear support shaft 74. When the fixing member 96 is fixed, a certain gap is left between the head portion 96B and the end face wall 77A. A compression spring 97 is provided in the gap around the shaft portion 96A of the fixing member 96. One end of the compression spring 97 is in contact with the end face wall 77A of the cylindrical portion 77, and the other end thereof is in contact with the head portion 96B of the fixing member 96 so that the compression spring 97 is compressed to some extent.

A friction member 98 made of felt is stuck on the surface of the end face wall 77A opposite to the idler gear body 95. The urging force of the compression spring 97 urges the cylindrical portion 77 toward the counter gear main body 95, and the cylindrical portion 77 is engaged with the counter gear main body 95 by the frictional force generated between the depressed portion 95A and the friction member 98. More specifically, the cylindrical portion 77 of the idler gear 70 is engaged with the idler gear body 95 by the frictional force of the friction member 98, which prevents the cylindrical portion 77 from moving relative to the idler gear body 95 when the interference portion 94 does not interfere with the moving member 278, and which allows the cylindrical portion 77 to move relative to the idler gear body 95 when the interference portion 94 interferes with the moving member 278, as will be described below. With this structure, the cylindrical portion 77 formed integrally with the moving member 278 serves as an engaging member for connecting the moving member 278 and the intermediate gear main body 95.

The number of the moving members 278 corresponds to information on the amount of toner accommodated in the toner accommodating box 34 when a new developer cartridge 28 is used. In other words, the number of the moving members 278 corresponds to the maximum number of sheets 3 on which an image can be formed regarding the amount of toner accommodated in the toner accommodating box 34 (hereinafter referred to as the maximum printable sheet count).

More specifically, when two moving members 278 are provided as shown in fig. 16, the maximum printable number of sheets corresponding to the number of moving members 278 is 6000. When only one moving member 278 is provided, the maximum printable sheet count corresponding to the number of moving members 278 is 3000.

In this further form, the interference portion 94 provided on the intermediate gear cover 92 of the gear cover 66 is provided on the downstream side of the detection position with respect to the moving direction of the moving member 278, and projects radially inward from the inner peripheral surface of the outer peripheral wall 92A (see fig. 18).

< operation to inspect a New developer Cartridge according to the still further form >

A method of determining whether the developer cartridge 28 mounted in the main casing according to this further form is new or old, and determining the maximum printable sheet count of the developer cartridge 28 will be described below.

In this method, the front cover 2B is opened, and the process cartridge 17 containing a new developer cartridge is inserted into the main casing 2 from the inlet 2A. Alternatively, the front cover 2B is opened, and a new developer cartridge 28 is inserted from the inlet 2A into the process cartridge 17 already mounted on the main casing 2.

As shown in fig. 18, two moving members 278 are provided on the intermediate gear 70 in the developer cartridge 28. When the developer cartridge 28 is new, the moving member 278 is disposed upstream of the detection position, as shown in fig. 18. Therefore, when the developer cartridge 28 is loaded into the main casing 2, the moving member 278 does not contact the contact serrations 86 of the actuator 82, and the actuator 82 is in a normal state in which the light blocking portion 87 blocks the detection light of the optical sensor 83.

After the developer cartridge 28 is mounted in the main casing 2, the CPU100 starts the warm-up operation, and performs the idle rotation operation to rotate the agitator 36. During this operation, the intermediate gear 70 is driven by the motor 59 to rotate together therewith, causing the moving member 278 mounted on the cylindrical portion 77 to move in the circumferential direction E (counterclockwise direction in fig. 18). At this time, as shown in fig. 19, the tip of the (front) guide moving member 278 contacts the contact pawl 86 of the actuator 82 at the detection position in the downward movement. The actuator 82 rotates around the cylindrical insertion portion 85 in the direction against the urging force of the tension spring 89, so that the contact pawl 86 moves downward and the light blocking portion 87 moves upward, as indicated by the arrow F. Thus, the light receiving element receives the detection light from the optical sensor 83, which was blocked by the light blocking portion 87 when the actuator 82 was in the normal state. The optical sensor 83 sends a reception signal to the CPU100 according to the received light. The CPU100 recognizes the received signal as the first received signal and resets the number of printed sheets detected by the sheet discharge sensor 64.

As the intermediate gear 70 is further driven to rotate, the tip end of the (front) guide moving member 278 further presses the contact pawl 86 while sliding along the contact pawl 86, and then passes through and separates from the contact pawl 86. Therefore, when the contact point between the moving member 278 and the contact pawl 86 is removed, the urging force of the tension spring 89 causes the actuator 82 to rotate about the cylindrical insertion portion 85 in the direction opposite to the arrow F in fig. 19, so that the contact pawl 86 moves upward and the light blocking portion 87 moves downward until the actuator 82 returns to its normal state. At this time, the light blocking section 87 once again blocks the detection light of the optical sensor 83 that has been received by the light receiving element.

Similarly, when the intermediate gear 70 is further driven to rotate, the tip end of the (rear) tail moving member 278 contacts the contact pawl 86 of the actuator 82 at the detection position in the downward movement. The actuator 82 rotates around the cylindrical insertion portion 85 in the direction against the urging force of the tension spring 89, so that the contact pawl 86 moves downward and the light blocking portion 87 moves upward, as indicated by the arrow F in fig. 19. Thus, the light receiving element receives the detection light from the optical sensor 83, which was blocked by the light blocking portion 87 when the actuator 82 was in the normal state. The optical sensor 83 sends a reception signal to the CPU100 according to the received light. The CPU100 recognizes the received signal as a second received signal.

As the intermediate gear 70 is further driven to rotate, the tip end of the (rear) tail moving member 278 further presses the contact pawl 86 while sliding along the contact pawl 86, and then passes through and separates from the contact pawl 86. Therefore, when the contact point between the moving member 278 and the contact pawl 86 is removed, the urging force of the tension spring 89 causes the actuator 82 to rotate about the cylindrical insertion portion 85 in the direction opposite to the arrow F in fig. 19, so that the contact pawl 86 moves upward and the light blocking portion 87 moves downward until the actuator 82 returns to its normal state. At this time, the light blocking section 87 once again blocks the detection light of the optical sensor 83 that has been received by the light receiving element.

As shown in fig. 20, when the intermediate gear 70 is further rotated thereafter, the tip end of the (front) guide-and-movement member 278 comes into contact with the interference portion 94 protruding from the lowest portion of the inner peripheral surface of the outer peripheral wall 92A. When the distal end of the movement guide member 278 contacts the interference portion 94, the cylindrical portion 77 can slide relative to the idler gear body 95, and the idler gear body 95 idles relative to the cylindrical portion 77. Thus, the moving member 278 is prevented from moving together with the idler gear body 95. Therefore, even when the idler gear body 95 continues to rotate, the moving member 278 remains in contact with the interference portion 94, with the result that the tip end of the moving member 278 does not subsequently pass the detection position. Thus, the interference portion 94 prevents the moving member 278 from passing the detection position again. Therefore, after the CPU100 recognizes the second received signal, the actuator 82 no longer rotates with the rotation of the intermediate gear 70, and the light receiving element no longer receives the detection light from the optical sensor 83.

During this idle operation, the CPU100 determines whether the developer cartridge 28 is a new product according to whether the received signal is input from the optical sensor 83, and determines the maximum printable sheet count of the developer cartridge 28 according to the number of received signals input from the optical sensor 83.

More specifically, in the example shown in fig. 18 to 20, the CPU100 determines that the developer cartridge 28 is new based on recognizing the first received signal, as described above.

Further, the CPU100 associates the number of received signals input with information on the maximum printable sheet count. Specifically, for example, when two received signals are input, the CPU100 associates this number as a maximum of 6000 sheets to be printed. When a single received signal is input, the CPU100 associates this number as a maximum of 3000 sheets to be printed.

In the above examples of fig. 18-20, the CPU100 identifies the first and second received signals for a predetermined duration before the end of the idle operation. After recognizing the second received signal, the CPU100 determines the maximum printable number of sheets of the new developer cartridge 28 to be 6000.

Thus, when the developer cartridge 28 in the example of fig. 18 to 20 is loaded into the main casing 2, the CPU100 determines that the developer cartridge 28 is new, and determines that the maximum printable sheets of the developer cartridge 28 is 6000. After the developer cartridge 28 is mounted, the CPU100 calculates the actual number of printed sheets detected by the sheet discharge sensor 64, and issues a toner-out warning (not shown) through a control panel or the like when the actual number of printed sheets approaches or reaches 6000.

However, when one of the two moving members 2278 (the tail moving member 278) is omitted from the example of fig. 18 to 20 so that the developer cartridge 28 is equipped with only one moving member 2278 (see fig. 12), the CPU100 recognizes only one receipt signal when the developer cartridge 28 is mounted. Therefore, the CPU100 determines that the developer cartridge 28 is new and that the maximum printable number of sheets of the developer cartridge 28 is 3000. After the developer cartridge 28 is mounted, the CPU100 calculates the actual number of printed sheets detected by the sheet discharge sensor 64, and issues a toner-out warning (not shown) through a control panel or the like when the actual number of printed sheets approaches or reaches 3000.

However, if a new developer cartridge 28 loaded in the main casing 2 is temporarily removed and then reloaded, the CPU100 starts the warm-up process and performs the idle rotation operation to rotate the agitator 36. At this time, as described above, the moving member 278 does not pass the detection position, and the optical sensor 83 does not input the reception signal to the CPU 100. Therefore, the CPU100 determines that the developer cartridge 28 is old because no signal is received during idling.

Here, the developer cartridge 28 according to the invention is not limited to the structure having one or two moving members 278, but three or more moving members 278 may be provided. In this case, the CPU100 can determine the information of the developer cartridges 28 corresponding to the number of the moving members 278.

< Effect to inspect New developer Cartridge according to the still further form >

In the laser printer 1 as described above, when the developer cartridge 28 is loaded into the main casing 2, the motor 59 drives the intermediate gear 70. When the intermediate gear 70 is driven, the moving member 278 moves and passes the detection position. The information detection mechanism 81 detects the channel of the moving member 278. The CPU100 determines the information about the developer cartridge 28 (whether the developer cartridge 28 is new, and if new, the maximum printable sheet count of the developer cartridge 28) based on the detection result of the information detecting mechanism 81 (whether a signal is input and the number of input received signals). Therefore, the laser printer 1 capable of determining the relevant information of the developer cartridge 28 can be manufactured at a low manufacturing cost by a simple structure equipped with the single information detection mechanism 81.

After the information detection mechanism 81 checks the passage of the moving member 278, the interference portion 94 obstructs the moving member 278 to prevent it from subsequently passing the detection position. Therefore, when the developer cartridge 28 is mounted in the main casing 2 and the motor 59 drives the intermediate gear 70, the laser printer 1 according to the further form can easily and reliably determine whether the developer cartridge 28 is new or not based on the detection of the passage of the moving member 278 by the information detecting mechanism 81. Thus, the laser printer 1 can determine the age of the developer cartridge 28 from when it is determined to be new.

Since the information detection mechanism 81 gives way to the moving member 278 when detecting the passage, there is a possibility that a plurality of moving members 278 are provided and the plurality of moving members 278 pass the detection position. As a result, the CPU100 can determine the information of the plurality of developer cartridges 28 based on the number of the moving members 278 detected by the information detecting mechanism 81. Since the information on the developer cartridge 28 includes the maximum number of sheets printable in accordance with the amount of toner accommodated in the developer cartridge 28, it is possible to accurately determine the age of the developer cartridge 28 loaded into the main casing 2 and appropriately replace the developer cartridge 28 even when developer cartridges 28 of different toner amounts are used.

By providing the moving member 278 on the intermediate gear 70 in the developer cartridge 28, there is no need to provide a new transmission member for transmitting the driving force of the motor 59 to the moving member 278. Thus, it is possible to manufacture a more compact device while avoiding an increase in manufacturing cost and structural complexity.

By providing the moving member 278 on the intermediate gear 70, which is located at a position more freely than the input gear 67 and the agitator drive gear 71, the moving member 278 can be located at a position more easily detected by the information detecting mechanism 81.

Further, the position of contact between the moving member 278 provided on the intermediate gear 70 and the interfering portion 94 may be determined by providing the interfering portion 94 on the gear cover 66 and covering the intermediate gear 70 with the gear cover 66. This structure ensures that the interference portion 94 can reliably interfere with the moving member 278.

Although the moving member 278 contacts the contact pawl 86 of the actuator 82, the moving member 278 is able to pass through the detection position and then contact the interference portion 94 without being obstructed by the contact pawl 86. Thus, the information detection mechanism 81 can reliably detect the passage of the moving member 278.

After the information detection mechanism 81 checks the passage of the moving member 278, the interference portion 94 interferes with the moving member 278 and keeps the moving member 278 in the interfered state, thereby preventing the moving member 278 from moving together with the intermediate gear 70. In this way, the interference portion 94 prevents the information detection mechanism 81 from subsequently detecting the passage of the moving member 278 again. Thus, the laser printer 1 capable of determining the information relating to the developer cartridge 28 can be manufactured at a low manufacturing cost by a simple structure including the moving member 278 and providing the interfering portion 94 that can interfere with the moving member 278 so as not to move together with the intermediate gear 70.

Further, by engaging the cylindrical portion 77 of the idler gear 70 with the idler gear body 95 by the friction member 98, the moving member 278 and the idler gear 70 can be engaged by friction force in a simple structure, thereby enabling the laser printer 1 to determine information about the developer cartridge 28 while reducing the manufacturing cost.

Further, if the circumference of the moving member 278 is modified according to the information about the developer cartridge 28, the CPU100 can determine a plurality of pieces of information about the developer cartridges corresponding to different lengths based on the duration of time for which the information detecting mechanism 81 detects the moving member 278.

Although the present invention has been described in detail in the above-mentioned manner, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit of the invention.

< developer cartridge according to this further modification >

Fig. 21 is a sectional view of a gear cover-mounted developer cartridge according to a further modified form, in which like parts are denoted by like reference numerals to avoid repetitive description.

In the modification shown in fig. 21, the cylindrical portion 77 of the idler gear 70 is not engaged with the idler gear body 95 by the frictional force of the friction member 98, but is engaged with the idler gear body 95 by the shear pin 99 protruding from the end face wall 77A opposite to the idler gear body 95 toward the idler gear body 95. An engagement hole 95B is formed on the concave portion 95A of the idler gear body 95 at the position of the shear pin 99. The cylindrical portion 77 is engaged with the idler gear body 95 by inserting the shear pin 99 into the engagement hole 95B.

When the interference portion 94 does not interfere with the moving member 278, the cylindrical portion 77 of the idler gear 70 moves integrally with the idler gear main body 95 by the engagement between the shear pin 99 and the engagement hole 95B. When the interference portion 94 interferes with the moving member 278, the shear pin 99 is broken, and the movement of the idler gear 70 together with the idler gear main body 95 is released. Therefore, as shown in fig. 20, after the tip end of the (front) guide moving member 278 contacts the interfering portion 94, the moving member 278 does not move together with the idler gear body 95. Therefore, even when the idler gear body 95 continues to rotate, the moving member 278 remains in contact with the interference portion 94, with the result that the tip end of the moving member 278 does not subsequently pass the detection position. Thus, the interference portion 94 prevents the moving member 278 from passing the detection position again. Therefore, after the CPU100 recognizes the second received signal, the actuator 82 no longer rotates with the rotation of the intermediate gear 70, and the light receiving element no longer receives the detection light from the optical sensor 83.

Thus, in the modification described above, the laser printer 1 capable of determining the information relating to the developer cartridge 28 can be manufactured at a low manufacturing cost by a simple structure including the moving member 278 and providing the interfering portion 94 that can interfere with the moving member 278 so as not to move together with the intermediate gear 70.

In the above form, the moving member 78, the moving member 178, and the moving member 278 are provided on the intermediate gear 70. However, these moving members may be provided on another gear such as the agitator drive gear 71 or the developer roller drive gear 69.

In the above form, the developer cartridge 28 is provided independently from the process frame 51, and the photosensitive drum 27 is provided in the process frame 51. However, the developer cartridge may be formed integrally with the process frame 51.

Claims (25)

1. An image forming apparatus, comprising:

a device main body;

a driving force generating portion provided in the apparatus main body to generate a driving force;

a developer cartridge detachably mountable in the apparatus main body, the developer cartridge comprising:

a transmission member configured to be driven by the driving force and to move in a moving direction when the developer cartridge is loaded into the apparatus main body;

a moving part provided on the transmission member and moving together with the transmission member in a moving direction;

an interference portion provided downstream of a predetermined detection position in the moving direction so as to interfere with and prevent the moving portion from passing the predetermined detection position for a second time;

a detection unit that detects passage of the moving unit at the predetermined detection position; and

an information determining section that determines information relating to the developer cartridge based on a detection result of the detecting section;

the moving part is configured to irreversibly switch from a first position, in which the moving part is allowed to pass through a predetermined detection position, to a second position, in which the moving part is prohibited from passing through the predetermined detection position; and

wherein the interference portion obstructs the moving portion so as to cause the moving portion to change from the first position to the second position;

the moving portion is supported on the transmission member so as to be pivotable from the first position to the second position.

2. An image forming apparatus according to claim 1, wherein said moving section is substantially shaped like a rod having one end pivotally supported on said transmission member and the other end disposed to pass through said predetermined detection position and to be obstructed by said obstructing section.

3. The image forming apparatus according to claim 1, wherein said moving portion is substantially fan-shaped, a central angle side thereof is pivotably supported on said transmission member, and an arc outer peripheral side is provided to pass through said predetermined detection position and to be obstructed by said obstructing portion.

4. The imaging apparatus of claim 1, wherein the moving portion comprises a plurality of moving portions.

5. The image forming apparatus as claimed in claim 4, wherein the number of the plurality of moving parts corresponds to information on the developer cartridge; and

wherein the information determining portion determines the developer cartridge-related information based on the number of the plurality of moving portions detected by the detecting portion.

6. The image forming apparatus as claimed in claim 1, wherein a width of the moving portion in the moving direction corresponds to the information on the developer cartridge; and

wherein the information determining portion determines the developer cartridge-related information based on a detection cycle when the detecting portion detects the moving portion.

7. The image forming apparatus according to claim 1, wherein the developer cartridge-related information includes information indicating whether the developer cartridge is a new product.

8. The image forming apparatus according to claim 1, wherein the developer cartridge-related information includes information of an amount of the developer accommodated in the developer cartridge.

9. The imaging apparatus of claim 1, wherein the transmission member comprises a gear.

10. The image forming apparatus as claimed in claim 1, wherein the developer cartridge further comprises:

an input gear that engages with the driving force generating portion when the developer cartridge is loaded into the apparatus main body;

an agitator to agitate the developer contained in the developer cartridge; and

a stirring gear engaged with the stirrer,

wherein the transmission member includes an intermediate gear that transmits the driving force from the input gear to the stirring gear.

11. The image forming apparatus as claimed in claim 1, wherein the developer cartridge includes a cover member covering the driving member; and

wherein the interference portion is provided on the lid member.

12. The image forming apparatus as claimed in claim 1, wherein the developer cartridge includes a rotary shaft to rotatably support the transmission member;

wherein the driving force generating portion is provided so as to drive the transmission member to rotate about the rotation shaft when the developer cartridge is loaded into the apparatus main body; and

wherein, in the first position, the moving portion is provided on the transmission member so as to extend in a radial direction of the rotation shaft.

13. The image forming apparatus according to claim 1, wherein the detection portion includes a contact portion that comes into contact with the moving portion when the moving portion passes the predetermined detection position; and

wherein the moving portion is provided so as to pass through the predetermined detection position without being hindered by the contact portion when contacted by the contact portion.

14. A developer cartridge detachably mountable to a main assembly of an image forming apparatus, the developer cartridge comprising:

a transmission member configured to be driven by a driving force and to move in a moving direction when the developer cartridge is loaded into the apparatus body;

a moving part provided on the transmission member and moving together with the transmission member in a moving direction;

an interference portion provided downstream of a predetermined detection position in the moving direction so as to interfere with and prevent the moving portion from passing the predetermined detection position for a second time;

the moving part is configured to irreversibly switch from a first position, in which the moving part is allowed to pass through a predetermined detection position, to a second position, in which the moving part is prohibited from passing through the predetermined detection position; and

wherein the interference portion obstructs the moving portion to change the moving portion from the first position to the second position;

the moving portion is supported on the transmission member so as to be pivotable from the first position to the second position.

15. The developer cartridge according to claim 14, wherein the moving portion is substantially rod-shaped, and has one end pivotally supported on the transmission member and the other end disposed to pass through the predetermined detection position and be blocked by the blocking portion.

16. The developer cartridge according to claim 14, wherein the moving portion is substantially fan-shaped, a central angle side thereof is pivotably supported on the transmission member, and an arc outer peripheral side is provided to pass through the predetermined detection position and to be blocked by the blocking portion.

17. The developer cartridge according to claim 14, wherein the moving part comprises a plurality of moving parts.

18. The developer cartridge according to claim 17, wherein the plurality of moving parts correspond in number to information relating to the developer cartridge.

19. The developer cartridge according to claim 14, wherein a width of the moving portion in the moving direction corresponds to the information relating to the developer cartridge.

20. The developer cartridge according to claim 18, wherein the developer cartridge-related information comprises information indicating whether the developer cartridge is a new product.

21. The developer cartridge according to claim 18, wherein the developer cartridge-related information comprises information of an amount of developer accommodated in the developer cartridge.

22. The developer cartridge according to claim 14, wherein the drive member comprises a gear.

23. The developer cartridge according to claim 14, further comprising:

an input gear that engages with a driving force generating portion provided in the apparatus main body when the developer cartridge is loaded in the apparatus main body;

an agitator to agitate the developer contained in the developer cartridge; and

a stirring gear engaged with the stirrer,

wherein the transmission member includes an intermediate gear that transmits the driving force from the input gear to the stirring gear.

24. The developer cartridge according to claim 14, further comprising a cover member covering the transmission member,

wherein the interference portion is provided on the lid member.

25. The developer cartridge according to claim 14, wherein the developer cartridge comprises a shaft for rotatably supporting the transmission member;

wherein a driving force generating portion provided in the apparatus body is provided so as to drive the transmission member to rotate about the rotation shaft when the developer cartridge is loaded into the apparatus body; and

wherein, in the first position, the moving portion is provided on the transmission member so as to extend in a radial direction of the rotation shaft.