JP2019032379A - Developer replenishment control system, image forming apparatus, and developer replenishment control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer supply control system capable of suppressing the generation of skin stains and vertical band streaks caused by replacement of a new storage unit when a developer out of stock is detected. In a developer replenishment control system applied to this image forming apparatus, a control device that receives a detection result by a remaining amount detection sensor, which is a remaining amount detecting means in the developing device 4, is based on the remaining amount of toner. The driving amount of the driving mechanism is adjusted to control the amount of toner supplied from the toner cartridge 7 to the developing device 4. When the control device replenishes the developing device 4 with new toner by replacing the toner cartridge 7, the control device measures the amount of new toner replenished while the remaining amount of the old toner is between the lower limit of the remaining amount and the upper limit of the remaining amount. It is controlled based on the count value, and when the lower limit of the remaining amount continues a predetermined number of times, the display unit is used as a warning means to give an instruction to display a warning for replacement of the toner cartridge 7. [Selection diagram] Fig. 1

Description

  The present invention relates to a developer supply control system, an image forming apparatus, and a developer supply control method.

  2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses are widely used not only in large-scale office environments but also in various fields such as home offices and general users. In order to provide products that meet these demands, there is a demand for technology that can realize cost reduction, downsizing, long life, and stable operation. In particular, in recent circumstances, it is required to reduce the running cost of the image forming apparatus, and there is a strong demand for reducing the cost and extending the life of consumables exchanged by the user. Longer life means that the part replacement cycle can be extended.

  For this reason, in this type of image forming apparatus, an image forming unit (so-called process unit) including a developing device is extended as much as possible so that the replacement period is extended and the cost is reduced. However, if an attempt is made to extend the service life, the amount of toner as a developer to be held by the developing device increases accordingly, and thus a toner holding capacity must be ensured. As a result, the development device and the entire image forming apparatus are increased in size. In order to solve these problems, recently, the toner storage unit and the image forming unit of the developing device are detachably separated, and the toner is transferred from the storage unit to the image forming unit of the developing device while replacing only the storage unit with a short period. Tends to be adopted.

  However, even if such a separation configuration is adopted, for example, if a toner cartridge in the storage unit is replaced at the time of toner out detection, and new toner is supplied all at once while the toner weight in the developing device is small, the developing device The toner may not be fully regulated by the regulating member. In such a case, background stains and vertical stripes occur due to an excessive amount of toner transport.

  Therefore, in order to solve such problems, an “image forming apparatus” that always maintains an appropriate toner concentration after the toner end recovery (toner out recovery) operation and suppresses occurrence of abnormal images such as background stains and toner scattering (see FIG. Patent Document 1).

  The technique according to Patent Document 1 described above includes a toner end detection unit that detects a state in which toner to be supplied to a developing unit (developing apparatus) that contains a two-component developer is exhausted. In addition, a time detection unit is provided for detecting a leaving time from when the toner end detection unit detects a state where the toner has run out to when it is detected that the toner container is removed and the toner container is installed again. Therefore, the time detection means detects the leaving time, and controls the timing from when the toner container is installed again until image formation is restored based on the leaving time.

  However, according to the technique according to Patent Document 1, although the toner density after the toner end recovery operation can be stabilized, new toner is collectively collected in the developing unit (developing device) after replacement of a new toner cartridge at the time of toner end detection. The problem of being replenished is not addressed. As a result, it is not possible to sufficiently suppress the occurrence of background stains and vertical stripes resulting from the toner replenishment.

  The present invention has been made to solve such problems, and its technical problem is to suppress the occurrence of background dirt and vertical stripes resulting from replacement of a new storage section.

  In order to solve the above technical problem, an embodiment of the present invention detects a storage unit that stores a developer, a developing device that is replenished with the developer from the storage unit, and a remaining amount of the developer in the developing device. A developer replenishment control system comprising: a remaining amount detecting unit; and a control unit configured to control a replenishment amount of the developer from the storage unit to the developing device based on the remaining amount of the developer detected by the remaining amount detecting unit. And a counter that counts the consumption amount of the developer, and the control means counts the supply amount of the new developer when the new developer is replenished to the developing device by replacing the storage unit. It controls based on a value.

  According to the present invention, with the above configuration, it is possible to suppress the occurrence of background dirt and vertical stripes resulting from replacement of a new storage unit. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus including a developer supply control system according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating how a process unit is attached to and detached from the apparatus main body in the image forming apparatus illustrated in FIG. 1. FIG. 2 is a cross-sectional view illustrating a schematic configuration of a developing device provided in the image forming apparatus illustrated in FIG. 1. FIG. 4 is a schematic view seen from a direction orthogonal to the axis of the developing device shown in FIG. 3. FIG. 2 is a cross-sectional view illustrating a schematic configuration of a toner cartridge provided in the image forming apparatus illustrated in FIG. 1. FIG. 5 is a perspective view showing a schematic configuration of a remaining amount detection sensor provided in the developing device described in FIG. FIG. 2 is a characteristic diagram showing an outline of toner replenishment control by a control device provided in the image forming apparatus shown in FIG. 1 in relation to a toner amount with respect to time in comparison with a known technique. 2 is a flowchart showing an operation process of toner replenishment control by a control device provided in the image forming apparatus shown in FIG. 1. It is a flowchart which shows the detail of the normal supply process included in the operation | movement process shown in FIG.

  Hereinafter, a developer supply control system, an image forming apparatus, and a developer supply control method of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a schematic configuration of an image forming apparatus including a developer supply control system according to an embodiment of the present invention.

  Referring to FIG. 1, this image forming apparatus is for monochrome image formation, and a process unit 1 as an image forming unit is detachably attached to the apparatus main body 100. The process unit 1 includes a photosensitive member 2 as an image carrier that carries an image on the surface, a charging roller 3 as a charging unit that charges the surface of the photosensitive member 2, and a latent image on the photosensitive member 2 is visualized. And a developing device 4 as developing means. Further, the process unit 1 includes a cleaning blade 5 as a cleaning unit that cleans the surface of the photoreceptor 2. Further, the process unit 1 is detachably provided with a toner cartridge 7 serving as a storage unit for storing toner as a developer.

  The toner cartridge 7 has, as its container body 22, a toner storage unit 9 that stores toner to be replenished to the developing device 4, and a toner recovery unit 9 that collects waste toner removed by the cleaning blade 5. doing. In the present embodiment, a one-component developer composed only of toner not containing a carrier is used as the developer. Further, as the toner, a polyester toner whose base material is a polyester resin is used. Note that the present invention can also be applied to a developing device and an image forming apparatus in which a two-component developer composed of a toner and a carrier is used. When the present invention is applied to a two-component developing device, the remaining amount of toner as a developer is detected by a toner remaining amount detecting means.

  Further, the image forming apparatus is provided with a light emitting diode (LED) head array 6 as an exposure unit that exposes the surface of the photoconductor 2 at a position facing the photoconductor 2. In addition to the process unit 1, the image forming apparatus includes a transfer device 10 that transfers an image onto a paper P as a recording medium, a paper feeding device 11 that supplies the paper P, and a fixing device 12 that fixes the image transferred onto the paper P. And a paper discharge device 13 for discharging the paper P from the apparatus main body 100 to the outside. The paper P includes cardboard, postcards, envelopes, plain paper, thin paper, coated paper such as coated paper and art paper, tracing paper, and the like. An OHP sheet or the like can be used as a recording medium other than the paper P.

  The transfer device 10 includes a transfer roller 14 as a transfer member. The transfer roller 14 is in contact with the photosensitive member 2 with the process unit 1 mounted on the apparatus main body 100, and a transfer nip (contact) is formed at the contact portion between the two. The transfer roller 14 is applied with at least one of a predetermined direct current (DC) voltage and an alternating current (AC) voltage. The paper feeding device 11 includes a paper feeding cassette 15 that stores paper P and a paper feeding roller 16 that feeds the paper P stored in the paper feeding cassette 15. In addition, a pair of registration rollers 17 as timing rollers for transporting the paper P to the secondary transfer nip at a transport timing is provided on the downstream side in the transport direction of the paper P with respect to the paper feed roller 16.

  The fixing device 12 includes a fixing roller 18 as a fixing member and a pressure roller 19 as a pressure member. The fixing roller 18 is heated by a heating source such as a heater. The pressure roller 19 is pressed toward the fixing roller 18 and comes into contact with the fixing roller 18, and a fixing nip is formed at the contact portion. The paper discharge device 13 includes a pair of paper discharge rollers 20. The paper P discharged outside the apparatus by the paper discharge roller 20 is stacked on a paper discharge tray 21 formed by denting the upper surface of the apparatus main body 100. Incidentally, the configuration including the toner cartridge 7, the developing device 4, the remaining amount detecting means for detecting the remaining amount of toner in the developing device 4, and the control means for controlling the replenishment amount of toner from the storage unit to the developing device 4, It may be called a developer supply control system. The detailed configuration and functions will be described later.

  FIG. 2 is a schematic view showing how the process unit 1 is attached to and detached from the apparatus main body 100 in the image forming apparatus described above.

  Referring to FIG. 2, in this image forming apparatus, a cover 101 provided at the rear portion of the apparatus main body 100 can be opened and closed. When the cover 101 is opened, the light emitting diode head array 6 is retracted upward via the link mechanism. With such a configuration, it is possible to remove the process unit 1 from the rear (side) while avoiding interference with the light-emitting diode head array 6 with the cover 101 open. Further, here, the toner cartridge 7 can be attached and detached integrally from the back (side) of the apparatus main body 100 in a state where the toner cartridge 7 is attached to the process unit 1. Further, the toner cartridge 7 can be attached to and detached from the process unit 1 regardless of whether the process unit 1 is attached to or detached from the apparatus main body 100.

  FIG. 3 is a cross-sectional view showing a schematic configuration of the developing device 4 provided in the above-described image forming apparatus.

  Referring to FIG. 3, the developing device 4 includes a developing housing 30 and a developing roller 31 as a developer carrying member that carries toner. Further, the developing device 4 includes a supply roller 32 as a developer supply member that supplies toner to the developing roller 31 and a developing blade 33 as a regulating member that regulates the amount of toner carried on the developing roller 31. . Further, the developing device 4 includes a first toner conveying member 34 and a second toner conveying member 35 that convey toner.

  The developing roller 31 rotates in the counterclockwise direction in FIG. 3, and conveys the toner held on the surface to a position facing the developing blade 33 and the photosensitive member 2. The supply roller 32 is in contact with the developing roller 31 and rotates counterclockwise with respect to the developing roller 31 to supply the toner in the developing device 4 to the surface layer of the developing roller 31. Incidentally, a favorable toner supply function is secured by setting the rotation speed ratio between the developing roller 31 and the supply roller 32 to 1 here. The front end side of the developing blade 33 is in contact with the surface of the developing roller 31. The toner supplied onto the developing roller 31 by the supply roller 32 passes through the nip portion between the developing roller 31 and the developing blade 33, thereby being frictionally charged at the same time as its thickness is regulated.

  A toner cartridge 7 that contains replenishing toner is detachably mounted on the upper portion of the developing device 4. For this reason, a replenishing port 30 a for replenishing the toner in the toner cartridge 7 into the developing device 4 is formed in the upper part of the developing device 4. The replenishment of toner is performed based on the detection result of the remaining amount of toner in the developing device 4 by the remaining amount detection sensor 60 as the remaining amount detection means. That is, when the remaining amount sensor 60 detects that the amount of toner consumed in the developing device 4 is less than a predetermined value, the toner cartridge 7 is driven for a preset time. As a result, a predetermined amount of toner is supplied to the developing device 4. At this time, the control device as a control means provided in the image forming apparatus performs the drive mechanism according to the remaining amount lower limit value and the remaining amount upper limit value set in advance based on the remaining amount of toner detected by the remaining amount detection sensor 60. Adjust the drive amount. As a result, the amount of toner replenished from the toner cartridge 7 of the storage unit into the developing device 4 is controlled.

  The interior of the developing housing 30 includes a first housing portion A in which a replenishing port 30a is provided by a partition wall 36 provided substantially parallel to the axial direction of the developing roller 31, and developing means such as the developing roller 31 and the developing blade 33. And the second accommodating part B in which the is disposed. Here, the partition wall 36 stands up and down, and the first storage portion A and the second storage portion B are disposed adjacent to each other in the horizontal direction. A first toner conveying member 34 is disposed in the first accommodating portion A, and a second toner conveying member 35 is disposed in the second accommodating portion B. The developing device 4 and the toner cartridge 7 may be integrated.

  FIG. 4 is a schematic view seen from a direction perpendicular to the axis of the developing device 4 shown in FIG.

  Referring to FIG. 4, the toner can be moved by the first storage portion A and the second storage portion B in the developing device 4 at least at both ends in the longitudinal direction of the partition wall 36 inside the development housing 30. Openings 42 and 43 are opened. The toner replenished in the developing device 4 is conveyed to one side in the axial direction of the developing roller 31 by the first toner conveying member 34 installed in the first accommodating portion A. Thereafter, the toner moves from the openings 42 and 43 on the downstream side in the transport direction to the second storage unit B, and is transported by the first toner transport member 34 by the second toner transport member 35 provided in the second storage unit B. It is conveyed in the opposite direction.

  On the downstream side of the second toner conveying member 35, the toner can move to the second storage portion B through the openings 42 and 43 of the partition wall 36, and the toner in the developing device 4 can be circulated in the longitudinal direction. The toner conveyance speed can be controlled by the configuration of the first toner conveyance member 34 and the second toner conveyance member 35. When a screw member is used, the toner conveyance speed increases in proportion to the screw pitch. This is because the amount of toner to be conveyed per one rotation of the screw increases, but the toner conveying speed can also be controlled by a technique such as increasing the screw diameter.

  The first toner transport member 34 and the second toner transport member 35 have a structure capable of transmitting drive from a drive source installed in the apparatus main body 100 or the like by a drive transmission member 46 including gears, couplings, and the like. The toner in the developing device 4 can be moved with respect to the developing roller 31 by a supply roller 32 configured by a sponge or the like that can supply the toner to the developing roller 31. The drive transmission member 46 is included in a drive mechanism that is driven and controlled by the control device.

  FIG. 5 is a cross-sectional view illustrating a schematic configuration of the toner cartridge 7 provided in the above-described image forming apparatus.

  Referring to FIG. 5, in the toner replenishing container 50 of the toner cartridge 7, the agitator 52 fixed to the rotating shaft 53 rotates the charged toner to ensure fluidity, and the direction of the toner transport unit 51. Configured to supply. The agitator 52 can be exemplified by a case where it is made of a flexible material such as a PET film. In order to use up the toner in the toner replenishing container 50, it is desirable that the shape of the toner replenishing container 50 be an arc shape in accordance with the rotation activation of the agitator 52. The toner conveying unit 51 sends the toner in the toner replenishing container 50 in the axial direction of the rotation shaft 53 by rotating a member formed of a screw, a coil, or the like by a drive source installed in the apparatus main body 100. This drive source is also included in the drive mechanism that is driven and controlled by the control device.

  In the toner transport unit 51, the toner transport amount is controlled by the pitch diameter, size, rotation speed, and the like of the member, and the toner shortage is detected by the remaining amount detection sensor 60 installed in the developing device 4. In addition, in the toner transport unit 51, when the toner charge is confirmed by the remaining amount detection sensor by starting the rotation operation, the driving is stopped and the toner amount in the developing device 4 is stabilized, and the control is performed using a known technique. It is preferable to do.

  FIG. 6 is a perspective view showing a partial cross section of the schematic configuration of the remaining amount detection sensor 60 provided in the developing device 4 described above.

  Referring to FIG. 6, here, a case where an optical sensor is used as the remaining amount detection sensor 60 for detecting the remaining amount of toner in the developing device 4 is illustrated. The remaining amount detection sensor 60 includes a light emitting sensor, a first light guide 62 and a second light guide 63 made of a highly transparent resin material, and a light receiving sensor. In the remaining amount detection sensor 60, the light emitted from the light emitting sensor attached to the side surface of the main body of the developing device 4 is incident from the entrance of the first light guide 62 disposed on the side surface of the main body of the developing device 4. The main body of one light guide 62 is transmitted and guided into the developing device 4. The light guided to the inside of the developing device 4 is incident on the inlet of the second light guide 63 from the outlet of the first light guide 62 through the inner space of the developing device 4 and the main body of the second light guide 63. Is transmitted to the outside of the developing device 4. Thereafter, the light guided to the outside of the developing device 4 is received by a light receiving sensor attached to the side surface of the main body of the developing device 4 in the vicinity of the exit of the second light guide 63. The light receiving sensor detects the presence or absence of light by converting the amount of received light into a voltage.

  In the case of the remaining amount detection sensor 60, light emission is controlled by applying a voltage to the light receiving sensor when the remaining toner amount is detected, and the presence of toner in the internal space in the developing device 4 can be detected by the output of the light receiving sensor. It is possible. However, if toner, foreign matter, or the like adheres between the exit of the first light guide 62 and the entrance of the second light guide 63, the transmitted light is shielded when the remaining amount is detected. It becomes. Therefore, a cleaning member 61 such as a sheet material is attached to the rotation shaft of the screw at the remaining amount detection portion of the first toner conveying member 34, and the deposit on the light transmission path can be removed at the rotation cycle of the rotation shaft of the screw. It is desirable to provide a cleaning mechanism.

  In any case, the detection result of the remaining amount of toner by the remaining amount detection sensor 60 that detects the remaining amount of toner in the developing device 4 is sent to the control device. The image forming apparatus is provided with a counter that counts the remaining amount of toner as a consumption amount in advance. Therefore, the control device adjusts the driving amount of the driving mechanism in accordance with the remaining amount lower limit value and the remaining amount upper limit value set in advance based on the remaining amount of toner, and controls the toner replenishment amount from the toner cartridge 7 to the developing device 4. To do. At this time, when a new toner cartridge 7 is detected, the control device controls the new toner replenishment amount step by step based only on the count value of the counter when replenishing the developing device 4 with new toner.

  FIG. 7 is a characteristic diagram showing an outline of toner replenishment control by the control device provided in the image forming apparatus described above in relation to the toner amount with respect to time t in comparison with the comparative example.

  Referring to FIG. 7, in the characteristic C1 of the comparative example, new toner is replenished at once after replacement of a new toner cartridge 7. Here, the toner is replenished in the developing device 4 so that the toner amount reaches the detection upper limit with a steep slope from the detection lower limit in a short time, so that there is a possibility that background stains and vertical stripes may occur. is there.

  On the other hand, in the characteristic C2 according to the embodiment, the replenishment amount of new toner replenishment after replacement of a new toner cartridge 7 is performed stepwise with a gentle inclination based only on the count value. The “count value” refers to a dot counter that counts the number of dots corresponding to the number of pixels at the time of image formation, which will be described in detail later, or background stains that can be calculated from the travel distance of the developing device (a small amount of toner on the white paper portion). Consumption counter, a toner discharge amount counter during toner discharge control, and the like. Until the toner detection upper limit is reached, the toner is not replenished all at once, but the toner consumption amount is calculated only by this count value, and the toner corresponding to the toner consumption amount is gradually replenished. “Stepwise” indicates that the toner amount corresponding to the toner consumption amount is supplied in a plurality of times. After the toner is replenished stepwise based on the count value and the upper limit of the toner amount in the developing device 4 is detected by the remaining amount detection sensor 60, the remaining amount detection sensor provided in the count value and the developing device 4 60, the amount of toner in the developing device is detected, and the amount of toner replenished from the toner cartridge 7 to the developing device 4 is controlled. As a result, after the toner cartridge 7 is replaced with a new one, new toner is not replenished from the toner cartridge 7 into the developing device 4, and the occurrence of background stains and vertical stripes due to this is sufficiently suppressed. Further, when the remaining amount lower limit value continues for a predetermined number of times, the control device issues an instruction to display a warning about replacement of a new toner cartridge 7 using, for example, the display unit of the image forming apparatus as a warning unit. Or it is also possible to give an announcement warning by voice. As a result, the user (user) of the image forming apparatus can clearly grasp the time to replace the toner cartridge 7.

  FIG. 8 is a flowchart showing an operation process of toner replenishment control by the control device provided in the image forming apparatus described above. However, here, for example, it is assumed that the image forming apparatus is provided with a counter that counts the remaining amount of toner as a consumption amount in advance.

  Referring to FIG. 8, in the toner replenishment control operation process, first, the control device determines whether or not a new toner cartridge 7 has been detected (step S1). If the result of this determination is that a new article has not been detected, the routine proceeds to normal replenishment processing (step S2) described later. On the other hand, if a new article is detected, the toner consumption is estimated from the count value Ct of the counter (step S3). Incidentally, since it is assumed that the normal toner cartridge 7 is detected after the end of the toner (after the toner has run out), the amount of toner in the developing device 4 often indicates the lower limit of the remaining amount.

  Next, the control device determines whether or not the remaining amount of toner is the remaining amount upper limit value based on the detection result of the remaining amount of toner in the developing device 4 by the remaining amount detection sensor (step S4). As a result of this determination, if the remaining amount is the upper limit value, the normal processing of new toner from the new toner cartridge 7 is performed (step S5), and then the operation process ends. This normal replenishment (step S5) corresponds to a condition in which the normal value N1 of the toner replenishment amount is equal to or exceeds the count value Ct corresponding to the toner consumption amount. If it is not the remaining amount upper limit value (if it is the remaining amount lower limit value or an intermediate remaining amount intermediate value between the remaining amount lower limit value and the remaining amount upper limit value), a new toner replenishment from the new toner cartridge 7 (step S6) is performed. Do. Thereafter, the process returns to the process of estimating the toner consumption amount based on the count value Ct of the counter (step S3), and the subsequent operation process is repeated.

  In the above-described step supply (step S6), the range value N2 from the lower limit value to the upper limit value of the toner supply amount exceeds the normal value N1 of the toner supply amount, and the normal value N1 of the toner supply amount is the toner consumption amount. It corresponds to the condition that is equal to or exceeds the count value Ct corresponding to. That is, here, a new toner replenishment amount is replenished more than the count value Ct of the counter until the toner remaining amount shifts from the remaining amount lower limit value to the remaining amount upper limit value. Therefore, it is assumed that the range value N2 from the lower limit value to the upper limit value of the toner replenishment amount is larger than the count value Ct. In this way, after the step replenishment (step S6) is repeated until the remaining toner amount detection state reaches the remaining amount upper limit value, the operation process is ended.

  Incidentally, if the range value N2 from the lower limit value to the upper limit value of the toner replenishment amount is smaller than the count value Ct, the replenishment amount cannot catch up with the consumption amount, and the toner cartridge 7 is replaced with a new toner cartridge 7 at an early stage. Toner end detection occurs. If the range value N2 from the lower limit value to the upper limit value of the toner replenishment amount is larger than the count value Ct, the new toner replenishment amount from the new toner cartridge 7 is excessive and the toner transport amount is excessive. As a result, vertical stripes occur during image formation.

  FIG. 9 is a flowchart showing details of the normal supply process (step S2) included in the operation process shown in FIG.

  Referring to FIG. 9, here, similarly to the case where a new toner cartridge 7 is detected, the control device estimates the toner consumption by the count value Ct of the counter (step S21). Thereafter, the control device determines whether or not the remaining amount of toner is an intermediate value of the remaining amount based on the detection result of the remaining amount of toner in the developing device 4 by the remaining amount detection sensor (step S22). If the result of this determination is that the toner remaining amount is an intermediate value, the toner is replenished according to the count value of the counter corresponding to the toner consumption (step S23), and the operation process is terminated. This replenishment (step S23) processing corresponds to a condition in which the upper limit value N3 of the toner replenishment amount exceeds the normal value N1 of the toner replenishment amount.

  Incidentally, if the upper limit value N3 of the toner replenishment amount is smaller than the count value Ct, the replenishment amount cannot catch up with the consumption amount, and toner end detection occurs early. On the other hand, if the upper limit value N3 of the toner replenishment amount is larger than the count value Ct, the toner replenishment amount is excessive and the toner transport amount is excessive, which causes vertical stripes during image formation. End up.

  Further, as a result of determining whether or not the remaining amount of toner is the remaining amount intermediate value (step S22), if it is not the remaining amount intermediate value, the control device determines whether or not the number of detections of the remaining amount lower limit value is the predetermined number n. (Step S24) is performed. As a result of the determination, if the number of times of detection of the remaining amount lower limit value has not reached the predetermined number n, the operation process is terminated after shifting to the process of the previous replenishment (step S23). On the other hand, if the number of times of detection of the remaining amount lower limit value has reached the predetermined number n, the control device displays the toner end on the display unit of the image forming apparatus (step S25) and ends the operation process. .

  In the image forming apparatus according to the above-described embodiment, a part of the structure is modified so that the process unit 1 and the toner cartridge 7 can be attached to and detached from the apparatus main body 100 as described with reference to FIG. The drive of the process unit 1 is connected to an image forming drive motor, and the drive of the toner cartridge 7 enables the drive source of the process unit 1 to be connected to the toner cartridge 7 by a clutch. Further, the toner supply from the toner cartridge 7 into the developing device 4 can be performed by connecting the drive source and the drive gear of the toner cartridge 7 as necessary. However, the configuration relating to the main parts including the toner cartridge 7, the developing device 4, the process unit 1 including the remaining amount detection sensor 60, the counter, and the control device can be regarded as a developer replenishment control system.

  To prepare the toner, 55 parts of polyester resin having a softening point of 130 ° C., 35 parts of polyester resin having a softening point of 104 ° C., 6 parts of carbon black, 3 parts of wax (paraffin wax), and CCA (E -84) was used in 1 part. Note that CCA is an abbreviation for charge control agent. These toner materials are sufficiently mixed with a Henschel mixer, then melt-kneaded using a biaxial extrusion kneader with the discharge part removed, and the resulting mixture is rolled to a thickness of 2 mm with a cooling press roller and cooled. After cooling with a belt, it was coarsely pulverized with a feather mill. Then, after pulverizing with a mechanical pulverizer to an average particle size of 10 to 12 μm, and further pulverizing with a jet pulverizer while classifying coarse particles, the fine powder classification is performed using a rotor type classifier, and the volume average particle size is determined. A toner base having an average circularity of 0.925 and a diameter of 6 μm was obtained.

  In addition, 1 part of hydrophobic silica TS-500 and 2 parts of hydrophobic silica RY50 were added to 100 parts of this toner base material, and mixed with a 20 L Henschel mixer at a peripheral speed of 30 m / sec for 5 minutes. Thereafter, the toner was sieved with a sieve having an opening of 75 μm to obtain a pulverized toner. The particle diameter of the pulverized toner was 6 μm, and the average circularity was 0.926.

  Therefore, the above-mentioned pulverized toner and a modified image forming apparatus (printer) are used to perform toner replenishment control by the above-described control device, and 100,000 sheets of one sheet of white paper P are intermittently passed under different conditions of toner replenishment amount. Table 1 shows the results of checking whether or not vertical stripes were generated during image formation.

  From Table 1, according to the toner replenishment control by the control device in the image forming apparatuses according to the first and second embodiments, no vertical band streak occurs in image formation, and an image having no problem is obtained and evaluated. It turns out that it is a pass. On the other hand, according to the toner replenishment control by the control device in the image forming apparatuses according to the comparative example 1 and the comparative example 2, vertical stripes are generated in the image formation, and a problematic image is obtained and the evaluation is disqualified. I understand that. When the toner is a pulverized toner, since the particle size is large and the shape is irregular, the particle size is easily selected, and the difference between the new toner and the deteriorated toner becomes large. The effect of improving the problem of easily occurring during replenishment is great. This difference can be inferred to be due to how the control device performs stepwise control of the replenishment amount of pulverized toner.

  The toner replenishment control described with reference to FIGS. 8 and 9 includes a counter that counts the remaining amount of toner as consumption, and the control device performs stepwise control of a new toner replenishment amount only for the count value of the counter. The case where it performs based on was demonstrated. In addition, the control device has described the case where a new toner replenishment amount is replenished more than the count value of the counter before the remaining amount of toner shifts from the remaining amount lower limit value to the remaining amount upper limit value. This replenishment control includes a case where a new toner replenishment amount is replenished more than the count value of the counter from when the toner cartridge 7 is newly detected until the remaining amount of toner shifts to the remaining amount upper limit value. It can be regarded as being. In such a case, the toner draft surface in the developing device 4 can be raised stepwise to the level of the remaining amount upper limit value by supplying a larger amount of toner than the amount of toner consumed in the developing device 4.

  Incidentally, the counter described above may be a number counter that counts the number of sheets P that are recording media used for image formation using toner and new toner. In such a case, by calculating the toner consumption amount according to the number of sheets P, the control can be simplified and the cost can be reduced. The counter may be a travel distance counter that counts the travel distance in the transport mechanism that transports the paper P. In this case, by calculating the toner consumption amount according to the travel distance in the transport mechanism, the control can be simplified and the cost can be reduced. Further, the counter may be a dot counter that counts the number of dots corresponding to the number of pixels at the time of image formation using toner and new toner. In this case, the toner consumption can be estimated with high accuracy.

  In addition, in the developer replenishment control system of the image forming apparatus according to the embodiment, the control device replenishes a new toner replenishment amount less than the count value of the counter when the remaining amount of toner reaches the remaining amount upper limit value. You may do it. Here, after the toner draft surface in the developing device 4 reaches the remaining amount upper limit value, the toner replenishment amount is reduced so that the toner amount in the developing device 4 is always full when there is toner in the toner cartridge 7. To. Thereby, the number of times of supplying a large amount of toner at a time can be reduced.

  In addition, the control device may replenish a new toner replenishment amount larger than the count value of the counter until the remaining amount of toner shifts from the remaining amount upper limit value to the remaining amount lower limit value. Here, when the toner amount in the developing device 4 is not full and decreases, the toner replenishment amount is increased to make the toner full state. Thereby, the opportunity to replenish a large amount of toner at a time can be reduced.

  The basic function of the developer replenishment control system described above is that the developer replenishment control method allows the control means to control the toner replenishment amount when replenishing toner to the developing device 4 from the storage unit that stores toner as developer. In other words. This developer replenishment control method includes a remaining amount detecting step for detecting the remaining amount of toner in the developing device 4 by the remaining amount detecting means, and a counting step for counting the toner consumption amount by the counter. The developer replenishment control method includes a replenishment amount control step executed by the control unit. In the replenishment amount control step, when new toner is replenished to the developing device 4 by replacing the storage unit, the new toner replenishment amount is controlled stepwise based only on the count value of the counter.

  The present invention is not limited to the gist disclosed in the above-described embodiments and examples, and various modifications can be made without departing from the technical gist thereof, and the technical idea described in the claims. All the technical matters included in the subject matter are the subject of the present invention. Although the above-described embodiments and examples have shown preferable examples, those skilled in the art can implement various modified examples from the disclosed contents, and these are described in the appended claims. Within the technical scope.

DESCRIPTION OF SYMBOLS 1 Process unit 2 Photoconductor 3 Charging roller 4 Developing apparatus 5 Cleaning blade 6 Light emitting diode (LED) head array 7 Toner cartridge 8 Toner accommodating part 9 Toner collection part 10 Transfer apparatus 11 Paper feeder 12 Fixing apparatus 13 Paper discharge apparatus 14 Transfer Roller 15 Paper feed cassette 16 Paper feed roller 17 Registration roller 18 Fixing roller 19 Pressure roller 20 Paper discharge roller 21 Paper discharge tray 22 Container body 30 Development housing 30a Supply port 31 Development roller 32 Supply roller 33 Development blade 34 First toner conveyance Member 35 Second toner conveying member 36 Partition wall 42, 43 Opening portion 46 Drive transmission member 50 Toner supply container 51 Toner conveying portion 52 Agitator 53 Rotating shaft 60 Remaining amount detection sensor 61 Cleaning member 62 First light guide 63 Second light guide 100 Device main body 101 Cover A First storage B B Second storage P Paper

Japanese Patent No. 4622396

Claims (14)

A storage unit for storing the developer, a developing device for supplying the developer from the storage unit, a remaining amount detecting unit for detecting the remaining amount of the developer in the developing device, and the remaining amount detecting unit A developer replenishment control system comprising: control means for controlling a replenishment amount of the developer from the storage unit to the developing device based on the detected remaining amount of the developer,
A counter for counting consumption of the developer;
The control means controls the supply amount of the new developer based on the count value of the counter when a new developer is supplied to the developing device by exchanging the storage unit. Agent replenishment control system. A storage unit for storing the developer, a developing device for supplying the developer from the storage unit, a remaining amount detecting unit for detecting the remaining amount of the developer in the developing device, and the remaining amount detecting unit A developer replenishment control system comprising: control means for controlling a replenishment amount of the developer from the storage unit to the developing device based on the detected remaining amount of the developer,
When a new developer is replenished to the developing device by exchanging the storage unit, the control means replenishes the new developer in a plurality of times until the amount of developer in the device reaches a predetermined amount. A developer replenishment control system. The developer control system according to claim 2.
A developer replenishment control system comprising a counter for counting the amount of developer consumption, wherein the developer replenishment amount is controlled based on a counter value of the counter. In the developer replenishment control system according to claim 1 or 3,
The control means controls the replenishment amount of the developer from the storage unit to the developing device according to the preset remaining amount lower limit value and remaining amount upper limit value set by the remaining amount detecting means. Agent replenishment control system. The developer replenishment control system according to claim 3.
When the new developer is replenished to the developing device by exchanging the storage unit, the control means controls the replenishment amount of the new developer stepwise based only on the count value of the counter. A developer replenishment control system. The developer replenishment control system according to claim 4.
The control means includes
From the time when a new developer is supplied to the developing device by exchanging the storage unit, the amount of supply of the new developer is the counter until the remaining amount upper limit value of the remaining amount detecting means is detected. Based on the count value of
After the remaining amount upper limit is detected, based on the count value and the detection state by the remaining amount detecting means,
A developer replenishment control system that controls a replenishment amount of the developer from the storage unit to the developing device. The developer replenishment control system according to claim 4.
A warning means for warning the new replacement of the storage unit,
The developer supply control system according to claim 1, wherein the control means instructs the warning means to warn of replacement of the storage unit with a new one when the remaining amount lower limit value has continued a predetermined number of times. The developer replenishment control system according to claim 4.
The control means replenishes the new developer supply amount more than the count value of the counter until the remaining amount of the developer shifts from the remaining amount lower limit value to the remaining amount upper limit value. A developer replenishment control system. The developer replenishment control system according to claim 4.
The control means increases the replenishment amount of the new developer more than the count value of the counter until the remaining amount of the developer shifts to the remaining amount upper limit value from a new detection state of the storage unit. A developer replenishment control system characterized by replenishing. The developer replenishment control system according to claim 4.
The counter is
A number counter for counting the number of recording media used for image formation using the developer and the new developer, or a recording medium used for image formation using the developer and the new developer. A travel distance counter that counts a travel distance in a transport mechanism that transports, or a dot counter that counts the number of dots corresponding to the number of pixels at the time of image formation using the developer and the new developer. Developer supply control system. The developer replenishment control system according to claim 4.
The developer replenishment control system, wherein when the remaining amount of the developer reaches the remaining amount upper limit value, the control means replenishes the new developer replenishment amount less than the count value of the counter. The developer replenishment control system according to claim 4.
The control means replenishes the new developer supply amount more than the count value of the counter until the remaining amount of the developer shifts from the remaining amount upper limit value to the remaining amount lower limit value. A developer replenishment control system.   An image forming apparatus comprising the developer supply control system according to claim 1. A developer replenishment control method in which the control means can control the replenishment amount of the developer when replenishing the developer to the developing device from a storage unit for storing the developer,
A remaining amount detecting step of detecting a remaining amount of the developer in the developing device by a remaining amount detecting means;
A counting step of counting consumption of the developer by a counter;
A replenishment amount control step for controlling a replenishment amount of the new developer based on a count value of the counter when a new developer is replenished to the developing device by replacing the storage unit by the control unit; A developer replenishment control method comprising: