JP2010014820A - Toner cartridge and image forming apparatus - Google Patents

Abstract

The length of a sheet member is adjusted according to the remaining amount of toner, a certain amount of toner is conveyed over a long period of time, and the toner remains in a container without applying excessive pressure or shearing force to the toner. Provided is a toner cartridge that avoids this.
In a toner cartridge including a rotating shaft that is pivotally supported by a toner container and a sheet member that is held by the rotating shaft, and the toner cartridge that conveys toner by the sheet member, the rotating shaft includes the sheet member. A center column 5 for fixing a peripheral edge portion 7a on one side of the sheet 7 and winding it around the outer periphery, and a passage member 6 having a slit-shaped passage 6d for fitting the center column 5 with a gap 6c and holding the sheet member 7 movably. With. In response to an external operation force, the central column 5 switches to a state in which the central column 5 can rotate relative to the passage member 6, the sheet member 7 wound around the central column 5 is rewound, and the sheet member is rotated from the axis 4 a of the rotation shaft 4. The length to 7 peripheral edge part 7b is changed.
[Selection] Figure 2

Description

  The present invention relates to a toner cartridge used in an electrophotographic image forming apparatus and an image forming apparatus equipped with the toner cartridge.

  An image forming apparatus that forms an image by using an electrophotographic method can form a high-quality image with a simple operation and is easy to maintain. Therefore, the image forming apparatus is widely used in copying machines, printers, facsimiles, and the like, and is widely used. ing. A general image forming apparatus includes a photosensitive drum that forms an electrostatic latent image, a developing unit that develops the electrostatic latent image, a transfer unit that transfers a toner image onto a recording medium (paper), and a toner image. It is composed of a fixing unit fixed on a recording medium. The developing unit applies the toner supplied from the toner cartridge to the electrostatic latent image on the photosensitive drum and develops the toner. The toner consumed by the development is appropriately replenished by the user.

  As for toner replenishment, a method of replacing the toner cartridge as it is (that is, removing an empty toner cartridge with no remaining toner from the image forming apparatus and installing a new toner cartridge instead) has become mainstream. Empty toner cartridges are often reused without being discarded due to the recent increase in awareness of environmental problems.

  The toner cartridge includes a storage container for storing toner, and the storage container has a toner discharge port for supplying the stored toner to the developing unit. There is a toner cartridge in which the toner discharge port faces downward and a toner discharge roller is provided at the toner discharge port. In this case, the toner discharge roller 1 is basically set so that a fixed amount of toner is discharged from the toner discharge port per one rotation of the toner discharge roller, but the toner discharge roller 1 depends on whether the toner remaining in the toner cartridge is large or small. Emissions per revolution vary. Further, since the toner is very fine and light particles, it is difficult to completely consume the toner in the toner cartridge, such as remaining on the container wall surface and adhering.

  In order to solve such a problem, for example, in Patent Document 1, a toner discharge port is formed laterally on the horizontal wall of the container of the toner cartridge, and the rotary shaft and the rotary shaft are held in the container. A toner replenishing means comprising a flexible sheet member is arranged, and the toner is transported to the toner discharge port by rotating the sheet member in contact with the inner wall surface of the container. A developing device is disclosed in which a constant amount of toner is always discharged from the discharge port. In the developing device described in Patent Document 1, no toner discharge roller is provided at the toner discharge port.

Also, in the case of a toner cartridge having a toner discharge roller at the toner discharge port, if the remaining amount of toner in the toner cartridge decreases, the amount of toner transported to the toner discharge roller will decrease, so the toner discharge roller will rotate. By changing the time, reduction of the toner discharge amount has also been suppressed.
JP 2002-132032 A

  In the developing device described in Patent Document 1, the flexible sheet member is rotated while being in contact with the inner wall surface of the container so that the toner can be conveyed even when the remaining amount of toner is small. Since it is always in contact with the inner wall surface, there is a risk that an unnecessarily large pressure, shearing force, etc. may be applied to the toner in the toner cartridge.

  In the developing device described in Patent Document 1, the ratio of the toner discharge distance from the toner discharge port between the maximum state and the minimum state of the remaining amount of toner in the toner cartridge is regulated to a predetermined value or less. Since the toner in the cartridge is limited to a structure that replenishes toner from the lateral direction with respect to the developing unit, the toner cartridge cannot be applied to a toner cartridge that replenishes the developing unit from above with the toner discharge port facing downward.

  The present invention has been made in consideration of the above-described circumstances. Regardless of the decrease in the remaining amount of toner, the length of the sheet member is adjusted in accordance with the remaining amount of toner, and a constant amount is obtained over a long period of time. To provide a toner cartridge that can maintain toner discharge amount by conveying toner, and can prevent toner from remaining in a container without applying excessive pressure or shearing force to the toner. With the goal.

  In addition, the present invention provides a stable image over a long period of time despite a decrease in the remaining amount of toner in the toner cartridge, and is economical because the toner in the toner cartridge is reliably consumed. It is an object of the present invention to provide an image forming apparatus that is excellent in replacement workability by suppressing contamination due to toner falling and scattering.

  A toner cartridge according to the present invention is disposed inside a toner container, receives a rotating shaft pivotally supported by the toner container, a sheet member held by the rotating shaft, and an operating force from the outside. And a length changing mechanism capable of changing a length from the axis of the rotating shaft to the peripheral edge of the sheet member in a direction orthogonal to the axis.

  According to the present invention, an operation force is applied to the length changing mechanism provided in the toner cartridge, and the rotation shaft of the sheet member disposed in the toner storage container and held by the rotation shaft pivotally supported by the container is used. The length from the axial center to the peripheral edge in the direction orthogonal to the axial center (hereinafter abbreviated as the length of the sheet member) can be changed. By increasing the length of the sheet member and rotating the rotating shaft, it is possible to enhance the conveying action for conveying the toner in the toner container. Further, the toner in the container with a small remaining amount can be effectively conveyed by increasing the length of the sheet member so that the peripheral edge is in contact with the inner wall surface of the container and rotating the rotating shaft.

The toner cartridge according to the present invention is the above-described invention, wherein the toner container has a toner discharge port, and a rotatable toner discharge roller is disposed in the toner discharge port inside the toner container. It is characterized by being.
According to the present invention, the toner conveyed to the toner discharge port by the sheet member is discharged from the toner discharge port with the rotation of the toner discharge roller disposed in the toner discharge port. For example, the toner is discharged with the toner discharge port facing downward. In the toner cartridge, the length of the sheet member can be adjusted according to the remaining amount of toner in the container, and an appropriate toner discharge amount from the toner discharge port can be maintained.

  In the toner cartridge according to the present invention, in the above invention, the sheet member has a rectangular shape, the rotation shaft fixes a peripheral portion of one side of the sheet member, is wound around the outer periphery, and holds a central column. A slit is provided in which a gap is provided between the central column and the outer periphery around which the sheet member is wound, and the central column communicates with the gap to hold the sheet member movable in a direction perpendicular to the axis of the central column. A passage member having a plurality of passages, and the passage member is connected to the central column so as to be switchable between a relatively rotatable state and a relatively non-rotatable state, and the length changing mechanism includes the central column and the passage. A switching force receiving portion that receives an operation force for switching the member to a relatively rotatable state, and a rotation that receives an operation force that relatively rotates the central column and the passage member so as to rewind the sheet member wound around the central column. And having a receiving portion.

According to the present invention, the sheet member in which the peripheral edge of one side of the rectangular shape is fixed to the central column is wound around the outer periphery of the central column and is positioned in the gap between the central column and the passage member that fits in the central column. Further, it is held in a slit-like passage of the passage member communicating with the gap so as to be movable in a direction perpendicular to the axis of the central column. Then, an operation force is applied to the switching force receiving portion of the length changing mechanism to switch the central column and the passage member to a relatively rotatable state, and the sheet member wound around the central column is wound around the rotating force receiving portion of the length changing mechanism. Applying an operation force to rotate the central column and the passage member relative to each other so that the length from the axis of the rotating shaft to the peripheral edge of the sheet member in the direction perpendicular to the axis is increased, and then receiving the switching force By switching the central column and the passage member into a state in which relative rotation is impossible without applying an operating force to the portion and the rotational force receiving portion, the sheet member having an increased length is held on the rotation shaft.
Accordingly, the sheet member can be reliably held by the central column and the passage member provided on the rotation shaft, and the sheet member is wound around the outer periphery of the center column inside the rotation shaft, so that the periphery of the rotation shaft The space in the container is effectively used and does not interfere with the toner transportability.

  In the toner cartridge according to the present invention, in the above-described invention, the central column extends to the outside of the toner container, a recess is provided on an outer periphery of the extended portion, and the passage member extends from the central column. And extending to the outside of the toner container in a state of being externally fitted to the installation portion, and a radial through hole is provided in the extension portion, and passes through the through hole of the passage member and engages with the recess of the central column. And a connecting pin for connecting the passage member to the central column in a relatively non-rotatable manner, and a biasing member for biasing the connecting pin toward the side engaged with the recess, and the switching force receiving portion includes: A pin moving operation provided on the connecting pin to move the connecting pin from a position engaged with the concave portion to a position penetrating the through hole and not engaged with the concave portion against a biasing force of a biasing member. A force receiving portion, and the rotational force receiving portion rotates around the central pillar. Characterized in that it is a rotational driving force receiving portion provided for transmitting the driving force.

  According to the present invention, the connecting pin urged by the urging member is provided in the radial direction provided in the extended portion of the passage member that is fitted around the extended portion of the central column extended outside the toner container. By passing through the through hole and engaging with a recess provided on the outer periphery of the extended portion of the central pillar, the passage member is connected to the central pillar in a relatively non-rotatable manner. Then, an operation force is applied to the pin moving operation force receiving portion provided in the connection pin, and the through hole is penetrated from the position where the connection pin is engaged with the recess against the biasing force of the biasing member. The center column can be rotated relative to the passage member by moving to a position where it does not engage, and the center column can be rotated relative to the passage member by transmitting the rotational driving force to the rotational driving force receiving portion provided on the central column. Then, after unwinding the sheet member wound around the central pillar, by not applying an operating force to both receiving portions of the connecting pin and the central pillar, the passage member is connected to the central pillar in a relatively non-rotatable manner, The state in which the length of the sheet member is increased by rewinding the sheet member wound around the central column is maintained. Therefore, it is possible to obtain a toner cartridge having a simple and inexpensive structure in which the passage member can be switched between a relatively rotatable state and a relatively unrotatable state with respect to the central column by using the connecting pin.

The toner cartridge according to the present invention is characterized in that, in the above-described invention, the urging member is an elastic rubber material that presses and holds the connecting pin against the passage member.
According to the present invention, the connecting pin that passes through the through hole of the extending portion of the passage member and engages with the concave portion provided on the outer periphery of the extending portion of the central pillar is pressed against the passage member by the elastic rubber material and held. The Therefore, a toner cartridge having a simple and inexpensive structure that can use the elastic rubber material to reliably bias and hold the connecting pin can be obtained.

The toner cartridge according to the present invention is characterized in that, in the above-described invention, the sheet member is a flexible sheet having a thickness of 0.3 mm to 2 mm.
According to the present invention, when the flexible sheet having a thickness of 0.3 mm or more and 2 mm or less comes into contact with the inner wall surface of the toner storage container, the flexible sheet presses the inner wall surface with an appropriate force to bend, and the toner in the container is removed. It can be transported without leaving it.

  An image forming apparatus according to the present invention includes a photosensitive drum on which an electrostatic latent image is formed, a charging unit for charging the surface of the photosensitive drum, and an electrostatic latent image on the surface of the photosensitive drum. An exposure unit that develops an electrostatic latent image on the surface of the photosensitive drum to form a toner image, a transfer unit that transfers the toner image on the surface of the photosensitive drum to a recording medium, and the photosensitive unit An image forming apparatus comprising: a cleaning unit that cleans the surface of a body drum; and a fixing unit that fixes a toner image transferred to the recording medium. The toner is replenished from the toner cartridge, and an operating means for operating the length changing mechanism and a rotation arranged in the toner container in response to a decrease in the toner amount in the toner container. Shaft center And a controlling means for performing control to actuate the operating means so as to increase the length to the periphery of the sheet member in a direction orthogonal to the Luo axial center.

  According to the present invention, the electrostatic latent image on the surface of the photosensitive drum charged by the charging unit and having the electrostatic latent image formed by the exposure unit is developed by the developing unit to form a toner image, and the developed photosensitive The toner image on the surface of the body drum is transferred to the recording medium by the transfer unit, the toner remaining on the surface of the photosensitive drum is cleaned by the cleaning unit, and the toner image transferred to the recording medium is fixed by the fixing unit. The developing unit is supplied with toner from the mounted toner cartridge, and as the amount of toner in the toner storage container of the toner cartridge decreases due to the supply of toner to the developing unit, the rotation disposed in the toner storage container Operation control of the operating means for operating the length changing mechanism of the toner cartridge is executed so as to increase the length from the axial center of the shaft to the peripheral edge of the sheet member in the direction orthogonal to the axial center. As a result, the transporting action of transporting the toner in the toner storage container is enhanced, the amount of toner replenished from the toner storage container to the developing unit is maintained, and the sheet member is further in contact with the inner wall surface of the container. By increasing the length, the toner in the container with a small remaining amount is effectively conveyed and supplied to the developing unit.

In the image forming apparatus according to the present invention, in the above-described invention, the operation unit abuts against a pin moving operation force receiving portion of the connection pin and causes the connection pin to resist the urging force of the urging member. An operation member that moves from a position engaged with the through hole to a position that does not engage with the concave portion, and a rotational driving force receiving portion provided on the central column, and a rotational driving force is applied to the central column. And a rotary drive shaft for transmission.
According to the present invention, in the mounted toner cartridge, the biasing member passes through the through hole provided in the extending portion of the passage member and engages with the concave portion provided in the outer periphery of the extending portion of the central column. The operating member comes into contact with the pin movement operating force receiving portion provided on the biased connecting pin, and penetrates the through hole from the position where the connecting pin is engaged with the recess against the biasing force of the biasing member. By moving to a position that does not engage with the recess, the central column can rotate relative to the passage member, and the rotational driving force is transmitted by connecting the rotational driving shaft to the rotational driving force receiving portion provided on the central column. By doing so, the center column can be rotated relative to the passage member, the sheet member wound around the center column can be rewound, and the length of the sheet member can be increased. Thereafter, by releasing the contact of the operation member with the receiving portion of the connecting pin, the passage member is connected to the central column so as not to be relatively rotatable, and the state in which the length of the sheet member is increased is maintained. Therefore, an image forming apparatus having a suitable operation means for changing the length of the sheet member for a toner cartridge having a simple and inexpensive structure that can be switched between a relatively rotatable state and a relatively unrotatable state by a connecting pin. A device is obtained.

In the image forming apparatus according to the present invention, in the above-described invention, the image forming apparatus includes detection means for detecting a time during which the toner discharge roller is driven to rotate, and the control means rotates the toner discharge roller detected by the detection means. The control is executed when the time reaches a set time.
According to the present invention, when the rotation driving time of the toner discharge roller that is disposed in the toner discharge port and discharges the toner to the developing unit with rotation reaches the set time, the length of the sheet member in the toner container is increased. Control is executed. Accordingly, a decrease in the remaining amount of toner in the toner cartridge is appropriately detected based on the rotation driving time of the toner discharge roller, and the length of the sheet member is increased in response to the decrease in the remaining amount of toner, thereby increasing the conveying action for the toner. Thus, it is possible to maintain an appropriate toner replenishment amount for the developing unit.

The image forming apparatus according to the present invention includes, in the above-described invention, a detection unit that detects a decrease in the amount of toner in the toner storage container, and the control unit includes the detection unit in the toner storage container detected by the detection unit. The control is executed when the decrease in the toner amount reaches a set amount.
According to the present invention, when the decrease in the toner amount in the toner storage container is detected and the decrease in the toner amount reaches a set amount, the control for increasing the length of the sheet member in the toner storage container is executed. Accordingly, a decrease in the toner amount in the toner cartridge is directly detected, and the length of the sheet member is increased corresponding to the decrease in the remaining amount of toner, and the conveying action for the toner is increased, so that an appropriate toner replenishment amount for the developing unit Can be maintained.

According to the toner cartridge of the present invention, the length of the sheet member is increased to enhance the conveying action for the toner in the toner storage container, and the length of the sheet member is increased so that the peripheral edge contacts the inner wall surface of the container. Since the toner in the container is effectively transported, the length of the sheet member is adjusted according to the amount of remaining toner, and is constant over a long period of time despite the decrease in the amount of toner remaining in the container. An amount of toner can be conveyed to maintain the toner discharge amount.
Also, when the amount of toner remaining in the container is large at the initial stage of use, the periphery of the sheet member is not brought into contact with the inner wall surface of the container, and when the amount of toner remaining in the container is greatly reduced, Since the length of the sheet member is increased until it comes into contact with the inner wall surface of the container, a toner cartridge that can prevent toner from remaining in the container without applying excessive pressure or shearing force to the toner is provided. The As a result, the external additive, which is a component in the toner, is not embedded in the surface of the toner particles, and the toner is not agglomerated due to a rise in the toner temperature. Therefore, characteristics such as the toner charge amount can be maintained.

  According to the image forming apparatus of the present invention, the length of the toner conveying sheet member provided in the toner container is increased in accordance with a decrease in the amount of toner in the toner container of the mounted toner cartridge. Controlled and high toner transporting operation maintains the amount of toner replenished from the toner container to the developing unit, so that a stable image can be obtained over a long period of time despite a decrease in the remaining amount of toner in the toner cartridge. Is obtained. Also, the length of the sheet member is increased so that the sheet member contacts the inner wall surface of the container, and the toner in the container with a small remaining amount is effectively conveyed and replenished to the developing unit. As it is reliably consumed and economical, it is possible to prevent toner from remaining in the used toner cartridge as much as possible, so that contamination due to falling or scattering of toner is suppressed at the time of toner cartridge replacement. An excellent image forming apparatus is provided.

  Embodiments of a toner cartridge according to the present invention and an electrostatic electrophotographic image forming apparatus equipped with the toner cartridge according to the present invention will be described below with reference to the drawings.

  1 and 2 are cross-sectional views showing the structure of the toner cartridge 10 according to the present invention. FIG. 1 shows the start of use, and FIG. 2 shows a state in which the remaining amount of toner is reduced. 3 is a plan sectional view taken along line III-III in FIG. 2, FIG. 4 is a sectional plan view taken along line IV-IV in FIG. 2, and FIG. 5 is a sectional view taken along line VV in FIG.

  The toner cartridge 10 includes a toner storage container 1 which is a square cylindrical container having a semi-cylindrical bottom side. The toner storage container 1 stores toner T and has a removable upper lid 1a. A protrusion 1b protruding parallel to the cylinder axis of the toner container 1 is provided on the upper part of one of the horizontal walls parallel to the cylinder axis of the toner container 1, and a toner discharge port 2 is provided in the protrusion 1b. It is provided. The toner discharge port 2 is a substantially rectangular opening having a long side parallel to the cylinder axis of the toner container 1 and faces obliquely downward.

  A toner discharge roller 3 having a rotation axis parallel to the cylinder axis of the toner container 1 is provided at a position that closes the toner discharge port 2. The toner discharge roller 3 is formed by laminating a porous elastic body (sponge) of foamed ester polyurethane foam on a stainless steel shaft portion 3 a, and the shaft portion 3 a is pivotally supported by the toner container 1. By providing a foamed elastic body having elasticity on the surface layer of the toner discharge roller 3, it is possible to prevent toner leakage from the gap with the container wall when the toner cartridge 10 is transported (when not in use). When the toner cartridge 10 is mounted in the image forming apparatus (when used), the toner can be efficiently discharged from the toner discharge port 2. As a material for the porous elastic body, silicone rubber, EPDM, and the like can be used in addition to polyurethane, but a polyurethane foam is particularly preferable in terms of durability and toner transportability. The shaft portion 3a of the toner discharge roller 3 extends outside the toner container 1, and a gear 3b that receives a rotational driving force from the outside is fixed to the extended portion.

  A rotation shaft 4 is provided substantially in the center of the internal space of the toner container 1 in parallel with the cylinder axis of the toner container 1. The rotating shaft 4 includes a columnar central column 5 and a flat prismatic channel member 6 having an inner space for accommodating the central column 5 and positioned outside the central column 5. The passage member 6 has a cylindrical portion 6 f with a reduced diameter at both ends, and the cylindrical portion 6 f is pivotally supported by the toner container 1. The central column 5 is rotatably fitted by a cylindrical portion 6 f of the passage member 6, and has a gap 6 c between the central column 5 and the passage member 6. Accordingly, the axis 4 a of the rotating shaft 4 coincides with the axis of the cylindrical portion 6 f of the passage member 6 and the central column 5.

  The passage member 6 can be divided into two members 6 a and 6 b through a surface parallel to the cylinder axis of the toner container 1 through the inner space that houses the central column 5. The two members 6a and 6b in the coupled state are in close contact on one side with the central column 5 in between, and fixed by, for example, screws 6e, but on the other side, a slit-shaped passage 6d parallel to the flat surface of the rectangular column. Is formed. One end of the passage 6 d communicates with the inner space, and the other end is opened to the internal space of the toner container 1.

  A rectangular sheet member 7 has a peripheral edge 7 a on one side of the rectangle fixed to the outer periphery of the central column 5, and is wound around the central column 5. The sheet member 7 passes through the slit-like passage 6 d of the passage member 6, protrudes from the open end of the passage 6 d, and is provided so that the peripheral edge 7 b on the other side of the rectangle is located in the internal space of the toner container 1. The sheet member 7 is a polyethylene terephthalate (PET) sheet having flexibility. As a material for the sheet member 7, in addition to PET, a plate-like member that can be elastically deformed such as nylon, polypropylene, urethane rubber, and silicone rubber can be used, but PET has moderate elasticity (flexibility). This is preferable. Further, the thickness of the sheet member 7 is preferably in the range of 0.3 mm to 2 mm when the toner T is pumped and conveyed. When the thickness is less than 0.3 mm, the toner T cannot be pumped up due to insufficient strength. When the thickness exceeds 2 mm, the sound during pumping increases and the toner T rises up. There is a risk of inconvenience such as damage.

  The central column 5 has an extended portion 5 a extending to the outside of the toner container 1 at one end side, and the passage member 6 is externally attached to the extended portion 5 a of the central column 5. It has the extended part 6g extended in this. The extending portion 6g of the passage member 6 includes a portion continuous with one of the divided members 6a and a portion continuous with the other member 6b. A concave portion 5a1 is provided on the outer periphery of the extending portion 5a of the central column 5, and a through hole 6b1 whose axial position coincides with the concave portion 5a1 of the central column 5 is provided in the extending portion 6g of the passage member 6. .

  A connecting pin 8 that penetrates the through hole 6b1 of the extending portion 6g of the passage member 6 from the outside and can be engaged with the concave portion 5a1 of the central column 5 is provided. The connecting pin 8 has a rectangular plate-like base portion 8a and a protruding portion 8b protruding perpendicularly from the center of the base portion 8a to the surface of the base portion 8a. An annular elastic rubber material 9 is provided so as to abut against the base portion 8 a of the connecting pin 8 and wind around the outer surface of the extending portion 6 g of the passage member 6. Is pressed to the side engaged with the recess 5a1. The connecting pin 8 urged by the elastic rubber material 9 has the base portion 8a abutting against the outer surface of the extending portion 6g of the passage member 6 before the protruding portion 8b passes through the through hole 6b1 and contacts the bottom portion of the concave portion 5a1. In this position, the engagement with the connecting pin 8 is maintained. As a result, the central column 5 and the passage member 6 are connected so as to rotate integrally. The extending portion 5a of the central column 5 protrudes in the axial direction from the end of the extending portion 6g of the passage member 6, and a gear 5b that receives a rotational driving force from the outside is fixed to the protruding portion of the central column 5. . Further, the base portion 8a of the connecting pin 8 is formed with a slope portion 8c in which a corner portion located on one side of the rectangular plate near the passage member 6 is chamfered with a surface parallel to the side.

  Next, an image forming apparatus to which the toner cartridge 10 according to the present invention is mounted will be described. FIG. 6 is a front sectional view showing the overall configuration of the image forming apparatus equipped with the toner cartridge 10 according to the present invention, and FIG. 7 is a sectional view showing the arrangement of the toner cartridge 10 and the developing unit.

  The image forming apparatus 30 includes a toner cartridge 10, a developing unit 20, a photosensitive drum 17, a charging unit 25, an exposure unit 22, a transfer unit 24, a cleaning unit 26, a fixing unit 23, a paper feed cassette 21, a paper discharge tray 29, and the like. A scanner unit 31 is provided.

  The photosensitive drum 17 is a roller-like member that is supported by a driving unit (not shown) so as to be rotatable about an axis, and on which an electrostatic latent image and thus a toner image is formed. The photosensitive drum 17 can be a roller-shaped member including a conductive substrate (not shown) and a photosensitive layer (not shown) formed on the surface of the conductive substrate. As the conductive substrate, a conductive substrate having a cylindrical shape, a columnar shape, a sheet shape or the like can be used, and among them, the cylindrical conductive substrate is preferable. As the photoreceptor layer, an organic photoreceptor layer, an inorganic photoreceptor layer, or the like can be used.

  As an organic photoreceptor layer, a charge generating layer which is a resin layer containing a charge generating substance and a charge photosensitive layer which is a resin layer containing a charge transporting substance, or a charge generating substance in one resin layer Examples thereof include a single-layer photoreceptor containing a charge transport material. Examples of the inorganic photoreceptor layer include a film containing one or more selected from zinc oxide, selenium, amorphous silicon and the like. A base film may be interposed between the conductive substrate and the photoreceptor layer, and a surface film (protective film) for mainly protecting the photoreceptor layer may be provided on the surface of the photoreceptor layer. .

  The charging unit 25 is a saw-tooth type charger that performs corona discharge on the photosensitive drum 17. A power source (not shown) is connected to the charging unit 25 and applies a voltage to the charging unit 25. The charging unit 25 receives a voltage from the power source and charges the surface of the photosensitive drum 17 to a predetermined polarity and potential. Other than the saw-tooth charger, a charger charger, a charging brush charger, a roller charger, a contact charger such as a magnetic brush, or the like can be used.

  The exposure unit 22 receives image information of a document read by the scanner unit 31 or image information from an external device, and irradiates the charged surface of the photosensitive drum 17 with signal light corresponding to the image information. As a result, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum 17. The exposure unit 22 uses a laser scanning device including a light source. The laser scanning device is a device that combines, for example, a light source, a polygon mirror, an fθ lens, a reflection mirror, and the like. As the light source, for example, a semiconductor laser, an LED array, an electroluminescence (EL) element, or the like can be used.

The developing unit 20 includes a developing tank 11, a developing roller 12, a stirring roller 13, a regulating member 14, and a toner concentration detection sensor 15.
The developing tank 11 is a cylindrical container member that rotatably supports the developing roller 12 and the agitation roller 13 and stores a two-component developer composed of toner and a carrier. The agitating roller 13 is rotationally driven by a driving unit (not shown) and agitates the two-component developer accommodated in the developing tank 11.

  The developing roller 12 conveys the two-component developer to the photosensitive drum 17 and is rotationally driven around an axis by a driving unit (not shown). The developing tank 11 is provided with a rectangular opening 16 whose long side is parallel to the axial direction of the developing roller 12. The developing roller 12 faces the photosensitive drum 17 through the opening 16, and On the other hand, it is provided so as to be separated with a gap. The two-component developer conveyed by the developing roller 12 comes into contact with the photosensitive drum 17 at a portion closest to the photosensitive drum 17. This contact area is a development nip portion. In the development nip portion, a developing bias voltage is applied to the developing roller 12 from a power source (not shown) connected to the developing roller 12, and the developer on the surface of the developing roller 12 is charged with the photosensitive drum. The toner is supplied to the electrostatic latent image on the surface 17.

  The regulating member 14 is a plate-like member extending parallel to the axial direction of the developing roller 12. One end of the short side direction is supported by the developing tank 11 above the developing roller 12 in the vertical direction, and the other end is the surface of the developing roller 12. Are spaced apart from each other. As the material of the regulating member 14, stainless steel can be used, but aluminum or synthetic resin can also be used.

A toner concentration detection sensor 15 is mounted on the bottom surface of the developing tank 11 below the stirring roller 13 in the vertical direction so that the sensor surface is exposed inside the developing tank 11.
As the toner concentration detection sensor 15, a general toner concentration detection sensor 15 can be used, and examples thereof include a transmitted light detection sensor, a reflected light detection sensor, and a magnetic permeability detection sensor. Among these, a magnetic permeability detection sensor is preferable. A power supply (not shown) is connected to the magnetic permeability detection sensor, and a drive voltage for driving the magnetic permeability detection sensor and a control voltage for outputting the detection result of the toner concentration to the control means are applied. The permeability detection sensor is a type of sensor that receives the application of voltage and outputs the toner concentration detection result as an output voltage value. Basically, the sensitivity near the median value of the output voltage is good, so the output voltage in the vicinity of the sensor. Is used by applying a voltage such that Such type of magnetic permeability detection sensors are commercially available, and examples thereof include TS-L, TS-A, TS-K (all are trade names, manufactured by TDK Corporation) and the like.

  A rectangular opening 11 a parallel to the axial direction of the stirring roller 13 is provided in the container wall of the developing tank 11 obliquely above the stirring roller 13. The toner cartridge 10 is disposed adjacent to the developing unit 20 so that a substantially rectangular toner discharge port 2 having a long side parallel to the cylinder axis of the toner container 1 faces the opening 11a. When not rotating, the toner discharge roller 3 shields the toner discharge port 2 from the inside of the toner container 1 and rotates to transfer the toner T conveyed by the sheet member 7 from the toner discharge port 2 to the developing tank 11. Discharge.

  The transfer unit 24 is a roller-like member that is rotatably supported by a support member (not shown) and is rotatably provided by a driving unit (not shown) so as to be in pressure contact with the photosensitive drum 17. For the transfer unit 24, for example, a roller-shaped member including a metal cored bar having a diameter of 8 to 10 mm and a conductive elastic layer formed on the surface of the metal cored bar is used. As the metal forming the metal core, stainless steel, aluminum, or the like can be used. As the conductive elastic layer, a rubber material in which a conductive material such as carbon black is blended with a rubber material such as ethylene-propylene rubber (EPDM), foamed EPDM, or foamed urethane can be used. The toner image is conveyed from the paper feed cassette 21 to the pressure contact portion (transfer nip portion) between the photoconductor drum 17 and the transfer portion 24 by the rotation of the photoconductor drum 17 from the paper feed cassette 21 via the paper feed roller 27. Recording media are supplied one by one.

  As the recording medium passes through the transfer nip portion, the toner image on the surface of the photosensitive drum 17 is transferred to the recording medium. A power source (not shown) is connected to the transfer unit 24, and a voltage having a polarity opposite to the charging polarity of the toner constituting the toner image is applied to the transfer unit 24 when the toner image is transferred to a recording medium. As a result, the toner image is smoothly transferred to the recording medium.

  The cleaning unit 26 includes a cleaning blade (not shown) and a toner storage tank (not shown). The cleaning blade is a plate-like member provided so as to extend in parallel with the longitudinal direction of the photosensitive drum 17 and so that one end in the short direction abuts the surface of the photosensitive drum 17. The cleaning blade removes toner, paper dust, and the like remaining on the surface of the photosensitive drum 17 from the surface of the photosensitive drum 17 after the toner image is transferred to the recording medium. The toner storage tank is a container-like member, and temporarily stores the toner removed by the cleaning blade. The surface of the photosensitive drum 17 after the toner image is transferred is cleaned by the cleaning unit 26.

  The fixing unit 23 includes a fixing roller 23a and a pressure roller 23b. The fixing roller 23a is a roller-like member that is rotatably supported by a support member (not shown) and is rotatable around an axis line by a drive unit (not shown). The fixing roller 23a has a heating member (not shown) inside, and heats and melts the toner constituting the unfixed toner image carried on the recording medium conveyed from the transfer nip portion to fix it on the recording medium. As the fixing roller 23a, for example, a roller-shaped member including a cored bar and an elastic layer is used. The core metal is formed of a metal such as iron, stainless steel, or aluminum. The elastic layer is formed of an elastic material such as silicone rubber or fluorine rubber, for example. The heating member receives heat from a power source (not shown) and generates heat. A halogen lamp, an infrared lamp, etc. can be used for a heating member.

  The pressure roller 23b is a roller-like member that is rotatably supported and is provided so as to come into pressure contact with the fixing roller 23a by a pressure member (not shown). The pressure roller 23b rotates following the rotation of the fixing roller 23a. A pressure contact portion between the fixing roller 23a and the pressure roller 23b is a fixing nip portion. The pressure roller 23b promotes fixing of the toner image to the recording medium by pressing the toner in a molten state against the recording medium when the fixing roller 23a is heated and fixed to the recording medium. A roller-like member having the same configuration as that of the fixing roller 23a can be used for the pressure roller 23b. A heating member may also be provided inside the pressure roller 23b. A heating member similar to the heating member inside the fixing roller 23a can be used.

  In the fixing unit 23, when the recording medium to which the toner image is transferred passes through the fixing nip portion, the toner constituting the toner image is melted and pressed against the recording medium, and the toner image is fixed to the recording medium. The recording medium on which the image is printed is discharged to a paper discharge tray 29 via a paper discharge roller 28.

  The paper feed cassette 21 is a tray that stores recording media such as plain paper, coated paper, color copy paper, and OHP film. A recording medium is fed one by one in synchronization with the toner image on the surface of the photosensitive drum 17 being conveyed to the transfer nip portion by a pickup roller (not shown) and a conveying roller.

  The scanner unit 31 is provided with a document setting tray (not shown), an automatic reversing document feeder (RADF), and the like, and a document reading device (not shown). The automatic reversing document conveying device conveys a document placed on a document set tray to a document placing table of a document reading device. The document reading device includes a document placing table, a document scanning device, a reflecting member, and a line sensor including a photoelectric conversion element (for example, a charge coupled device (hereinafter referred to as “CCD”)), and is placed on the document placing table. The image information of the original is read every plural lines, for example every ten lines. The document placing table is a glass plate for placing a document for reading image information.

  The document scanning device includes a light source (not shown) and a first reflecting mirror, reciprocates at a constant speed V in parallel along the surface of the document mounting table, and emits light on the image forming surface of the document placed on the document mounting table. And a reflected light image is obtained by light irradiation. The first reflecting mirror reflects the reflected light image toward the reflecting member. The reflecting member includes a second reflecting mirror, a third reflecting mirror, and an optical lens (not shown), and forms a reflected light image obtained by the document scanning device on the licensor. The reflection member reciprocates at a speed of V / 2 following the reciprocation of the document scanning device. The second and third reflecting mirrors reflect the reflected light image so that the reflected light image faces the optical lens. The optical lens forms a reflected light image on the licensor. The licensor includes a CCD circuit (not shown) that photoelectrically converts a reflected light image formed by the optical lens into an electrical signal, and outputs an electrical signal that is image information to an image processing unit in a control means (not shown). The image processing unit converts image information input from an external device such as a document reading device or a personal computer into an electrical signal and outputs the electrical signal to the exposure unit 22.

  Next, on the toner cartridge 10 side, the length from the axis 4a of the rotating shaft 4 to the peripheral edge 7b of the sheet member 7 in the direction orthogonal to the axis 4a can be changed by receiving an operating force from the outside. The length changing mechanism and the operation means on the image forming apparatus side for operating the mounted toner cartridge 10 will be described. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7, FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 7, and FIG. 10 is a view schematically showing an operation member for operating the toner cartridge.

  When the toner cartridge 10 is mounted, a rotation drive shaft 18 capable of transmitting a rotation driving force to the gear 5b is provided at a position where the toner cartridge 10 is engaged with the gear 5b of the central column 5, and meshes with the gear 3b of the toner discharge roller 3. A rotational drive shaft 19 capable of transmitting rotational drive force to the gear 3b is provided at the position. Although not shown in FIGS. 8 and 9, a sheet rotation motor 18a connected to the rotation drive shaft 18 and a toner discharge motor 19a connected to the rotation drive shaft 19 are provided (FIG. 12). The sheet rotation motor 18a and the toner discharge motor 19a are stepping motors.

  An operation having a wedge-shaped portion 34a having an inclined shape that can move in a direction parallel to the base surface of the base portion 8a of the connecting pin 8 and abut against the inclined surface portion 8c of the base portion 8a when the toner cartridge 10 is mounted. An arm 34 is provided. Although not shown, the elastic rubber material 9 is provided with an opening through which the wedge-shaped portion 34a can pass. The operation arm 34 has two long holes 34b and 34b which are parallel to the longitudinal direction of the arm and engaged and guided by the pins 38 and 38. On the other hand, one end 36a is connected to the plunger 37a of the solenoid 37, and a drive arm 36 is provided that is pushed and pulled in a direction parallel to the base surface of the base 8a of the connection pin 8. The drive arm 36 is parallel to the longitudinal direction of the arm. It has a long hole 36 b engaged and guided by the pin 39. Further, a swing arm 35 is provided which is swingably supported at the middle point 35a and has long holes 35b and 35c which are parallel to the longitudinal direction of the arm at both ends. A pin 34c provided at the other end of the operation arm 34 engages with a long hole 35b at one end of the swing arm 35 so as to be movable along the long hole, and a pin 36c provided at the other end of the drive arm 36 The movable arm 35 is engaged with a long hole 35c at the other end so as to be movable along the long hole. A spring 40 is provided for pulling the operation arm 34 in a direction in which the wedge-shaped portion 34 a is separated from the connecting pin 8.

  With the above configuration, when the solenoid 37 is actuated and the plunger 37a is pulled, the other end of the swing arm 35 is pulled toward the solenoid 37, and one end of the swing arm 35 is moved toward the connecting pin 8. The arm 34 moves against the pulling force of the spring 40. As a result, the wedge-shaped portion 34 a provided at one end of the operation arm 34 comes into contact with the inclined surface portion 8 c of the base portion 8 a of the connecting pin 8, and a force that pushes the connecting pin 8 away from the central column 5 acts. When the connecting pin 8 is separated from the central column 5 and the protrusion 8b of the connecting pin 8 is disengaged from the recess 5a1 of the central column 5 and only engaged with the through hole 6b1 of the passage member 6, the central column 5 and the passage It can rotate relative to the member 6. When the central column 5 rotates relative to the passage member 6, the sheet member 7 wound around the outer periphery of the central column 5 is rewound, and the length of the sheet member 7 protruding from the passage member 6 is increased. . Thereafter, when the operation of the solenoid 37 is stopped at a predetermined time, the protrusion 8b of the connecting pin 8 is engaged with the recess 5a1 of the central column 5 again so that the central column 5 and the passage member 6 rotate integrally (relatively). Non-rotatable).

  As shown in FIG. 7, when the sheet member 7 protruding from the passage member 6 is lengthened and the rotating shaft 4 is rotated in the arrow direction to rotate the sheet member 7, the toner T is transferred to the sheet member 7. And is pumped up toward the toner discharge roller 3. At this time, since the sheet member 7 has flexibility, the peripheral end portion 7 b slides on the inner wall of the toner container 1 and deforms along the inner wall, so that the toner is efficiently transferred to the toner discharge roller 3. Can be supplied well. The toner discharge roller 3 guides the toner conveyed by the sheet member 7 to the toner discharge port 2 by its rotation, and replenishes it to the developing tank 11.

  FIG. 11 is a block diagram showing a configuration around the control unit 41 according to the present invention. As the control unit 41, a unit that controls the entire image forming apparatus 30 may be used, but FIG. 11 shows a unit dedicated to the developing unit 20. The control unit 41 includes a ROM 41a and a RAM 41b in which programs, detection results by various sensors, setting values, table data, and the like are stored, various data (detection results, etc.) stored in the RAM 41b, and various types of data stored in the ROM 41a. A CPU (central processing unit) 41c that extracts a program for performing control and performs various detections and / or determinations is provided.

  The control unit 41 receives a detection signal from the toner concentration detection sensor 15, and the control unit 41 receives a drive signal to the sheet rotation motor 18 a, a drive signal to the toner discharge motor 19 a, and the solenoid. The drive signal to 37 is output.

  The control unit 41 controls the rotational driving of the toner discharge roller 3 in accordance with the detection result of the toner concentration in the developing tank 11 by the toner concentration detection sensor 15. That is, when it is determined that the detection result by the toner density detection sensor 15 is lower than the toner density setting value, a drive signal is sent to the toner discharge motor 19a, a drive signal is output to the toner discharge motor 19a, and the toner discharge roller 3 is rotationally driven. Let

  Further, when the new toner cartridge 10 is mounted, the control unit 41 resets the accumulated toner motor rotation time to zero and stores it in the RAM 41b. When the toner discharge motor 19a is driven to rotate, the value of the rotation driving time is updated by adding to the accumulated toner motor rotation time stored in the RAM 41b, and the updated accumulated toner motor rotation time value is stored in the RAM 41b. Remember.

Next, the length control operation of the sheet member 7 will be described. FIG. 12 is a flowchart showing a control procedure of the control unit 41 according to the present invention.
First, it is determined whether the accumulated toner motor rotation time is equal to or longer than a predetermined time (step S1). If the accumulated toner motor rotation time is equal to or longer than the predetermined time (step S1: YES), it is determined whether the printing operation is being performed (step S2). If the printing operation is being performed (step S2: YES), the printing operation is performed. Is stopped (step S3).

  When the printing operation is not being performed (step S2: NO) and after the printing operation is stopped (step S3), the solenoid 37 is operated (step S4), and the central column 5 is switched to be rotatable relative to the passage member 6. . Next, the sheet rotation motor 18a is rotated for a set time (step S5), and the central column 5 is rotated once in the direction in which the sheet member 7 is rewound with respect to the passage member 6. Thereafter, the operation of the solenoid 37 is stopped (step S6), the center column 5 is switched to be non-rotatable relative to the passage member 6, and then it is determined whether the printing operation is stopped (step S7), and the printing operation is stopped. If it is in progress (step S7: YES), the printing operation is resumed (step S8), and the process is terminated. If the printing operation is not stopped (step S7: NO), the process is terminated as it is.

  If the accumulated toner motor rotation time is not longer than the predetermined time (step S1: NO), the process is terminated as it is. Thereafter, the operation procedure for controlling the length of the sheet member 7 is repeatedly executed at a predetermined timing.

  In the above embodiment, only one recess 5 a 1 is provided on the outer periphery of the extending portion 5 a of the central column 5, and the length of the sheet member 7 is shortened by a unit of length corresponding to the outer peripheral length of the central column 5. However, the length of the sheet member 7 may be controlled in units of a length shorter than the outer peripheral length of the central column 5 by providing two or more recesses 5a1.

  In the above embodiment, the decrease in the remaining amount of toner in the toner cartridge 10 is indirectly detected based on the rotation drive time of the toner discharge motor 19a. However, the decrease in the remaining amount of toner in the toner cartridge 10 is directly detected. For example, a sensor (detection means) is provided on the wall of the toner container 1, and a detection signal from the sensor is input to the control unit 41. You may make it perform control which shortens the length of the sheet | seat member 7 when the set amount is reached.

FIG. 3 is a cross-sectional view showing the structure of the toner cartridge according to the present invention, showing the start of use. FIG. 4 is a cross-sectional view illustrating a structure of a toner cartridge according to the present invention, showing a state in which the remaining amount of toner is reduced. It is a plane sectional view in the III-III line position of FIG. It is a plane sectional view in the IV-IV line position of FIG. It is sectional drawing in the VV line position of FIG. 1 is a front cross-sectional view showing an overall configuration of an image forming apparatus equipped with a toner cartridge according to the present invention. FIG. 3 is a cross-sectional view illustrating an arrangement of a toner cartridge and a developing unit according to the present invention. It is sectional drawing in the VIII-VIII line position of FIG. It is sectional drawing in the IX-IX line position of FIG. FIG. 4 is a diagram schematically illustrating an operation member that operates the toner cartridge according to the present invention. FIG. 2 is a block diagram illustrating a configuration around a control unit of the image forming apparatus according to the present invention. 3 is a flowchart illustrating a control procedure of a control unit of the image forming apparatus according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Toner container 2 Toner discharge port 3 Toner discharge roller 4 Rotating shaft 4a Axis center 5 Center pillar 5a Extension part 5a1 Recessed part 5b Gear (Rotation drive force receiving part, rotational force receiving part)
6 passage member 6b1 through-hole 6c clearance 6d passage 6g extending portion 7 sheet member 7a peripheral portion 7b peripheral portion 8 connecting pin 8c slope portion (switching force receiving portion, pin moving operation force receiving portion)
9 Elastic rubber material (biasing member)
10 toner cartridge 18 rotation drive shaft (operation means)
DESCRIPTION OF SYMBOLS 17 Photosensitive drum 20 Developing part 22 Exposure part 23 Fixing part 24 Transfer part 25 Charging part 26 Cleaning part 30 Image forming apparatus 34 Operation arm (operation member, operation means)
41a RAM (detection means)
41c CPU (detection means, control means)

Claims (10)

A rotating shaft pivotally supported by the toner container, and a sheet member held by the rotating shaft;
A length changing mechanism that can change the length from the axial center of the rotating shaft to the peripheral edge of the sheet member in a direction orthogonal to the axial center in response to an operating force from the outside. Features toner cartridge. The toner container has a toner outlet;
The toner cartridge according to claim 1, wherein a rotatable toner discharge roller is disposed in the toner discharge port inside the toner container. The sheet member has a rectangular shape,
The rotating shaft is fitted with a gap between a central column that fixes a peripheral edge of one side of the sheet member and is wound around the outer periphery, and an outer periphery around which the sheet member is wound. A passage member having a slit-like passage communicating with the gap and movably holding the sheet member in a direction perpendicular to the axis of the central column, the passage member rotating relative to the central column It is connected to be able to switch between a possible state and a relative non-rotatable state,
The length changing mechanism includes a switching force receiving portion that receives an operation force for switching the central column and the passage member to a relatively rotatable state, the central column and the central column so as to rewind a sheet member wound around the central column. The toner cartridge according to claim 1, further comprising a rotational force receiving portion that receives an operation force that relatively rotates the passage member. The central column is extended to the outside of the toner storage container, a recess is provided on the outer periphery of the extended portion, and the passage member is fitted to the extended portion of the central column and the toner storage container It is extended to the outside, and a radial through hole is provided in the extended portion,
A connecting pin that passes through the through hole of the passage member and engages with the recess of the central column to connect the passage member to the central column in a relatively non-rotatable manner, and urges the connecting pin to engage with the recess. And a biasing member
The switching force receiving portion moves the connection pin from a position engaged with the recess to a position that penetrates the through hole and does not engage the recess against the urging force of the urging member. It is a pin moving operation force receiving part provided on the connecting pin,
The toner cartridge according to claim 3, wherein the rotational force receiving portion is a rotational driving force receiving portion provided to transmit a rotational driving force to the central column.   The toner cartridge according to claim 4, wherein the biasing member is an elastic rubber material that presses and holds the connecting pin against the passage member.   6. The toner cartridge according to claim 1, wherein the sheet member is a flexible sheet having a thickness of 0.3 mm to 2 mm. A photosensitive drum on which an electrostatic latent image is formed, a charging unit that charges the surface of the photosensitive drum, an exposure unit that forms an electrostatic latent image on the surface of the photosensitive drum, and the photosensitive drum A developing unit that develops an electrostatic latent image on the surface of the photosensitive drum to form a toner image, a transfer unit that transfers the toner image on the surface of the photosensitive drum to a recording medium, and a cleaning that cleans the surface of the photosensitive drum. An image forming apparatus comprising: a fixing unit configured to fix the toner image transferred to the recording medium;
The toner cartridge according to any one of claims 1 to 6, wherein the developing unit is replenished with toner from the toner cartridge,
The operating means for operating the length changing mechanism, and the axis in the direction perpendicular to the axis from the axis of the rotation shaft arranged in the toner container according to the decrease in the toner amount in the toner container. An image forming apparatus comprising: a control unit that executes control to operate the operation unit so as to increase the length of the sheet member to the peripheral edge.   The operating means contacts the pin movement operating force receiving portion of the connecting pin and penetrates the through hole from the position where the connecting pin is engaged with the recessed portion against the urging force of the urging member. And an operation member that moves to a position that does not engage with, and a rotation drive shaft that is connected to a rotation drive force receiving portion provided on the center column and transmits the rotation drive force to the center column. Item 8. The image forming apparatus according to Item 7. Detecting means for detecting the time when the toner discharge roller is driven to rotate;
9. The image forming apparatus according to claim 7, wherein the control unit executes the control when a rotation driving time of the toner discharge roller detected by the detection unit reaches a set time. . Detecting means for detecting a decrease in the amount of toner in the toner container;
9. The image according to claim 7, wherein the control unit executes the control when the decrease in the toner amount in the toner container detected by the detection unit reaches a set amount. Forming equipment.

Images