JP5509717B2 - Developing device, process cartridge including the same, and image forming apparatus - Google Patents

Description

  The present invention relates to a developing device equipped in an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile, a process cartridge and an image forming apparatus including the developing device, and particularly relates to improvements in toner collection and transfer technology.

  Due to the recent demands for higher image quality in copiers and printers, the toner particle size used in them is minimized, and it is possible to cope with lower power consumption. Tend to. In a developing device using these toners, a toner agglomerate tends to be generated in the developer circulation section, which is sandwiched between the developing sleeve and the layer thickness regulating member, and a defective image such as a blank image is formed. May occur.

  In order to solve these problems, a developing device has been invented that incorporates a control to reversely rotate the developing sleeve after an image forming operation is performed to some extent (see, for example, Patent Document 1). In the developing device of the present invention, after the developing operation is completed, the developing sleeve is reversely rotated to perform a panning operation for removing the developer between the latent image carrier and the developing device. By the reverse rotation of the developing sleeve, the loose agglomerates of toner accumulated in the vicinity of the layer thickness regulating member are pushed back to the developer circulating portion and are destroyed by being mixed with the developer in the developer circulating portion.

  Further, in order to reduce the cost of the image forming apparatus, since a device for reducing the number of input drives by engaging the developing sleeve gear and the agitation conveyance member gear is generally made, the agitation conveyance member is controlled by the reverse rotation control. Will reversely rotate in synchronization with the developing sleeve. Normally, the agitating / conveying member is installed in the developing container with a certain amount of room to move in the longitudinal direction. Moving. A seal member is installed between the agitating / conveying member and the developer container for the purpose of preventing leakage of the developer. Resin parts with good sliding properties and rubber parts having a lip shape are generally used. ing. When the agitating / conveying member slightly moves in the longitudinal direction by the reverse operation, a path for the developer to enter between the seal member and the agitating / conveying member is easily formed, and the developer leaks to the outside of the developing device. This is an issue.

  That is, the above problem will be described in more detail with reference to FIGS. 10 to 13 based on the configuration of a conventional drive gear train that reversely rotates the developing sleeve. In the following, for the sake of convenience, the developing unit (developing device) corresponding to yellow will be described, but the same applies to magenta, cyan, and black of other colors.

  FIG. 10 is a perspective view showing the configuration of a conventional drive gear train. As shown in FIG. 10, the drive input gear 59Y is a two-stage gear and rotates on a metal shaft fixed to the first housing 57Y. It is installed freely. The first housing 57Y is fitted and secured to the second housing 58Y by a snap fit. When the developing device is set in the image forming apparatus main body, the spur gear provided in the image forming apparatus main body and the spur gear at the tip end mesh with each other, and drive input is performed from the image forming apparatus main body at the time of image formation. As a result of the driving, the driving force is transmitted to the developer carrier gear 60Y directly meshed with the lower helical gear, and the developer carrier gear 60Y rotates in the direction of the arrow in the figure. A cylindrical through hole is formed in the shaft portion integrated with the developing sleeve of the developer carrier, and a parallel pin installed in the through hole enters a recess formed in the developer carrier gear 60Y. Fixed. As a result, the developer carrier gear 60Y and the developer carrier always rotate synchronously.

  Further, the helical gear formed in the lower stage of the drive input gear 59Y is directly meshed with the agitating / conveying member gear (helical tooth) 62Ya, and is rotated in the direction of the arrow in the drawing by the drive input from the image forming apparatus main body. Is done. At the end of the agitating / conveying member 55Ya, a D-shaped part is formed, and by always engaging with the D-shaped part formed on the agitating / conveying member gear 62Ya, they always rotate synchronously. It is configured. Parts such as an E-type retaining ring are used to prevent the stirring and conveying member gear 62Ya from coming off.

  61Y is an idler gear (lotus tooth) directly meshed with the agitating and conveying member gears 62Ya and 62Yb, and transmits the rotation of the agitating and conveying member gear 62Ya to the agitating and conveying member gear 62Yb. The device itself is rotatably installed on a metal shaft fixed to the first housing 57Y, and is prevented from coming off from the metal shaft by a snap fit.

  The agitating / conveying member gear 62Yb is driven by the idler gear 61Y and rotates in the direction of the arrow in the figure. Similarly to the relationship between the agitating / conveying member 55Ya and the agitating / conveying member gear 62Ya, a D-shaped part is formed at the end of the agitating / conveying member 55Yb, and the D-shaped part formed on the agitating / conveying member gear 62Yb It always rotates synchronously by fitting. Also in this case, parts such as E-type retaining rings are used for retaining the same.

  The above is a description of the gear operation during image formation, but control is performed to rotate the developer carrying member in the opposite direction to that during image formation for the purpose of breaking the loose agglomerates of toner. In that case, each gear rotates in the direction as shown in FIG.

  Usually, rotating parts such as agitating and conveying members are positioned in the longitudinal direction by placing parts such as E-type retaining rings at both ends after being set in the housing. However, since variations in parts processing and the like always occur, it is usual to set the interval between the grooves in which the E-type retaining ring is arranged wider than the longitudinal dimension of the housing. Therefore, it is inevitable that some backlash occurs in the longitudinal direction. The gear that drives the agitating and conveying member is a helical gear and receives a thrust according to the rotational direction (refer to FIG. 11 for the direction). The agitating / conveying members 55Ya and 55Yb rotate forward in the direction A in FIG. 12 during image formation, and continue to receive thrust along with the forward rotation. At the time of non-image formation in which reverse rotation control is performed, the image rotates reversely in the B direction, which is the reverse direction, and is moved within the range of rattling due to the thrust accompanying the reverse rotation. A rubber seal member 64Y having a lip portion as shown in FIG. 13 is used so that a developer having a small particle diameter does not leak to the outside by this movement. Due to the movement, the posture of the lip portion is changed and the margin for the developer leakage is lowered, that is, the sealing function is impaired. The seal member 64Y is normally used by being press-fitted into a bearing or the like. Also in this example, a bearing 63Y in which a seal member 64Y is press-fitted is used.

  In view of this, the present invention solves the problems of the conventional developing device, and is configured to prevent the agitation conveyance member from rotating in reverse rotation control, thereby preventing a reduction in the seal margin of the seal member. It is an object to provide an apparatus, a process cartridge including the apparatus, and an image forming apparatus.

In order to achieve the above object, the invention described in claim 1 is a magnet fixedly supported by a developer container containing developer, and supported on the outer periphery of the magnet so as to be rotatable in both forward and reverse rotation directions. A developer carrying member having a developing sleeve for conveying the developer adsorbed on the surface to a developing region facing the latent image carrying member on which the latent image is formed, and fixed to an end of the developer carrying member. A developer carrier gear that is rotated by drive transmission from the outside, an agitating and conveying member that agitates and conveys the developer sent from the developing sleeve, and an end of the agitating and conveying member that is fixed to the outside. And agitating and conveying member gear that is rotated in conjunction with the developer carrier gear by driving transmission of the developer carrier and controlled so that the developer carrier rotates in reverse during non-image formation. Protrusions are provided at the end of the member A groove portion that fits with the protrusion portion in the rotation direction with play is provided in the agitation conveyance member gear, and is configured so that the agitation conveyance member is not rotated in reverse rotation control by fitting the protrusion portion and the groove portion. It is characterized by.

  According to a second aspect of the present invention, in the first aspect, the stirring and conveying member is disposed in a pair so that the two-component developer can be circulated and conveyed while stirring in the longitudinal direction. The agitating / conveying member gears are fixed to the respective ends, and these agitating / conveying member gears are arranged directly or through meshing with idler gears, and either one of the agitating / conveying member gears is driven by external drive transmission. It is driven.

  A third aspect of the present invention is characterized in that, in the first or second aspect, the groove portion is provided in a fan shape at an angle in a range of 30 ° to 90 ° in the rotation direction.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, an impact absorbing material is installed on the side surface of the protruding portion of the stirring and conveying member or the inner wall of the groove portion of the stirring and conveying member gear. .

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the drive transmission from the outside is performed by a drive input gear meshing with a stirring and conveying member gear.

  According to a sixth aspect of the present invention, there is provided a process cartridge comprising the developing device according to any one of the first to fifth aspects. According to a seventh aspect of the present invention, there is provided an image forming apparatus comprising the developing device according to any one of the first to fifth aspects or the process cartridge according to the sixth aspect.

The present invention is as described above, and according to the first to third and fifth aspects of the present invention, a protrusion is provided at an end of the agitating and conveying member, and the protrusion is fitted with play in the rotation direction. A groove portion to be joined is provided in the agitating and conveying member gear, and the agitating and conveying member is configured not to reversely rotate in reverse rotation control by fitting the protrusion and the groove portion. of the reverse rotation, even if the rotation of the agitating and conveying member gear is integrated with it, since the agitation transport member itself is configured so as not to reverse rotation, the longitudinal direction of the fine moving inhibition of agitation conveying member described above Thus, the problem of the change in the posture of the seal member that has been occurring in the past is solved. Therefore, the sealing property is always kept good and the leakage of the developer can be prevented.

  According to the fourth aspect of the present invention, since the shock absorbing material is installed on the protrusion side surface of the agitating / conveying member or the inner wall of the groove portion of the agitating / conveying member gear, And the agitation transport member are eliminated, and the occurrence of a defective image due to the collision shock can be suppressed.

  According to the sixth aspect of the present invention, it is possible to provide a process cartridge including a developing device that can expect the above-described effects. According to the seventh aspect of the present invention, it is possible to provide an image forming apparatus including a developing device or a process cartridge that can be expected to have the above-described effects.

1 is a schematic front view of an entire color image forming apparatus showing an embodiment of the present invention. It is an expanded sectional view of an image creation part same as the above. It is a fragmentary perspective view which shows the stirring conveyance member which has a projection part in an edge part. It is a perspective view which shows the stirring conveyance member gear which has a groove part. It is a fragmentary perspective view which shows the rotation direction of the stirring conveyance member gear at the time of image formation, and the stirring conveyance member. It is a fragmentary perspective view which shows the rotation (reverse rotation) direction of the stirring conveyance member gear at the time of a non-image formation and a stirring conveyance member. It is a fragmentary perspective view which shows the drive part (reverse rotation) seen from the opposite side to FIG. It is the schematic of the image development apparatus which shows another embodiment. FIG. 3 is an enlarged cross-sectional view corresponding to FIG. 2 illustrating an example in which an image forming unit or the like is accommodated in a casing to form a process cartridge. It is a perspective view at the time of image formation which shows the conventional drive gear train. It is a perspective view at the time of non-imaging same as the above. It is drawing for demonstrating the direction of the thrust which acts on a stirring conveyance member in the same as the above. It is drawing of the seal | sticker part cross section of a stirring conveyance member same as the above.

  A color image forming apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

<Color image formation process>
First, the configuration and operation of the entire color image forming apparatus will be described with reference to FIGS.
FIG. 1 is an overall configuration diagram showing a printer as a color image forming apparatus, and FIG. 2 is an enlarged view showing an image forming unit thereof. As shown in FIG. 1, four toner containers 32Y, 32M, 32C, and 32K corresponding to the respective colors (yellow, magenta, cyan, and black) are attached to and detached from the toner container accommodating portion 31 at the upper part of the image forming apparatus main body 100. It is installed freely (changeable). An intermediate transfer unit 15 is disposed below the toner container housing 31. Image forming portions 6Y, 6M, 6C, and 6K corresponding to the respective colors (yellow, magenta, cyan, and black) are arranged in parallel so as to face the intermediate transfer belt 8 of the intermediate transfer unit 15.

  In FIG. 2, an image forming unit 6Y corresponding to yellow includes a latent image carrier 1Y, a charging unit 4Y disposed around the latent image carrier 1Y, a developing unit 5Y (developing device), a cleaning unit 2Y, a charge eliminating unit. Part (not shown) and the like. Then, an image forming process (charging process, exposure process, developing process, transfer process, cleaning process) is performed on the latent image carrier 1Y, and a yellow image is formed on the latent image carrier 1Y. .

  The other three image forming units 6M, 6C, and 6K have substantially the same configuration as that of the image forming unit 6Y corresponding to yellow except that the color of the toner to be used is different. A corresponding image is formed. Hereinafter, description of the other three image forming units 6M, 6C, and 6K will be omitted as appropriate, and only the image forming unit 6Y corresponding to yellow will be described.

  In FIG. 2, the latent image carrier 1Y is driven to rotate clockwise as indicated by an arrow in FIG. 2 by a drive motor (not shown). Then, the surface of the latent image carrier 1Y is uniformly charged at the position of the charging unit 4Y (charging process).

  Thereafter, the surface of the latent image carrier 1Y reaches the irradiation position of the laser beam L emitted from the exposure unit 7 (see FIG. 1), and an electrostatic latent image corresponding to yellow is formed by exposure scanning at this position. Formed (exposure process).

  Thereafter, the surface of the latent image carrier 1Y reaches a position facing the developing portion 5Y, and the electrostatic latent image is developed at this position to form a yellow toner image (developing step).

  Thereafter, the surface of the latent image carrier 1Y reaches a position facing the intermediate transfer belt 8 and the primary transfer bias roller 9Y, and the toner image on the latent image carrier 1Y is transferred onto the intermediate transfer belt 8 at this position. (Primary transfer process). At this time, a small amount of untransferred toner remains on the latent image carrier 1Y.

  Thereafter, the surface of the latent image carrier 1Y reaches a position facing the cleaning unit 2Y, and untransferred toner remaining on the latent image carrier 1Y at this position is mechanically collected by the cleaning blade 2a (cleaning). Process).

  Finally, the surface of the latent image carrier 1Y reaches a position facing an unillustrated neutralization unit, and the residual potential on the latent image carrier 1Y is removed at this position.

Thus, a series of image forming processes performed on the latent image carrier 1Y is completed.
The image forming process described above is performed in the other image forming units 6M, 6C, and 6K similarly to the yellow image forming unit 6Y. That is, the laser beam L based on the image information is emitted from the exposure unit 7 disposed below the image forming unit onto the latent image carriers of the image forming units 6M, 6C, and 6K. Specifically, the exposure unit 7 emits laser light L from a light source and irradiates the latent image carrier through a plurality of optical elements while scanning the laser light L with a polygon mirror that is rotationally driven.

Thereafter, the toner images of the respective colors formed on the latent image carriers through the development process are transferred onto the intermediate transfer belt 8 in an overlapping manner. In this way, a color image is formed on the intermediate transfer belt 8.
Here, the configuration of the intermediate transfer unit 15 will be described with reference to FIG. That is, the intermediate transfer unit 15 includes an intermediate transfer belt 8, four primary transfer bias rollers 9Y, 9M, 9C, and 9K, a secondary transfer backup roller 12, a cleaning backup roller 13, a tension roller 14, an intermediate transfer cleaning unit 10, Etc. The intermediate transfer belt 8 is stretched and supported by the three rollers 12 to 14 and is endlessly moved in the direction of the arrow in FIG.

  The four primary transfer bias rollers 9Y, 9M, 9C, and 9K respectively sandwich the intermediate transfer belt 8 with the latent image carriers 1Y, 1M, 1C, and 1K to form primary transfer nips. Then, a transfer bias reverse to the polarity of the toner is applied to the primary transfer bias rollers 9Y, 9M, 9C, and 9K.

  The intermediate transfer belt 8 travels in the direction of the arrow, and sequentially passes through the primary transfer nips of the primary transfer bias rollers 9Y, 9M, 9C, and 9K. Thus, the toner images of the respective colors on the latent image carriers 1Y, 1M, 1C, and 1K are primarily transferred onto the intermediate transfer belt 8 in a superimposed manner.

  Thereafter, the intermediate transfer belt 8 on which the toner images of the respective colors are transferred in a superimposed manner reaches a position facing the secondary transfer roller 19. At this position, the secondary transfer backup roller 12 sandwiches the intermediate transfer belt 8 with the secondary transfer roller 19 to form a secondary transfer nip. The four-color toner images formed on the intermediate transfer belt 8 are transferred onto a transfer material P such as transfer paper conveyed to the position of the secondary transfer nip. At this time, the untransferred toner that has not been transferred to the transfer material P remains on the intermediate transfer belt 8.

Thereafter, the intermediate transfer belt 8 reaches the position of the intermediate transfer cleaning unit 10. At this position, the untransferred toner on the intermediate transfer belt 8 is collected.
Thus, a series of transfer processes performed on the intermediate transfer belt 8 is completed.
Here, the transfer material P transported to the position of the secondary transfer nip is transported from the paper feed unit 26 disposed in the lower part of the apparatus main body 100 via the paper feed roller 27, the registration roller pair 28, and the like. It is what is done.

  Specifically, a plurality of transfer materials P such as transfer paper are stored in the paper supply unit 26 in a stacked manner. When the paper feed roller 27 is rotated in the counterclockwise direction in FIG. 1, the uppermost transfer material P is fed between the rollers of the registration roller pair 28. The transfer material P conveyed to the registration roller pair 28 is temporarily stopped at the position of the roller nip of the registration roller pair 28 that has stopped rotating. Then, the registration roller pair 28 is rotationally driven in synchronization with the color image on the intermediate transfer belt 8, and the transfer material P is conveyed toward the secondary transfer nip. In this way, a desired color image is transferred onto the transfer material P.

  Thereafter, the transfer material P on which the color image has been transferred at the position of the secondary transfer nip is conveyed to the position of the fixing unit 20. At this position, the color image transferred to the surface is fixed on the transfer material P by heat and pressure generated by the fixing roller and the pressure roller.

Thereafter, the transfer material P is discharged out of the apparatus through the rollers of the discharge roller pair 29. The transfer material P discharged from the apparatus by the discharge roller pair 29 is sequentially stacked on the stack unit 30 as an output image.
Thus, a series of image forming processes in the image forming apparatus is completed.

<Development details>
Next, the configuration and operation of the developing unit 5Y in the image forming unit 6Y will be described in more detail with reference to FIG.

  The developing unit 5Y includes a developer carrier 51Y that faces the latent image carrier 1Y, a layer thickness regulating member 52Y that faces the developer carrier 51Y, the first agitation conveyance path 53Y, and the second agitation conveyance path 54Y. The two agitating and conveying members 55Ya and 55Yb are disposed, a density detection sensor 56Y that detects the toner density in the developer, and the like. They are installed in the housing 57Y. The developer carrier 51Y includes a magnet fixed inside, a sleeve that rotates around the magnet, and the like. In the agitating / conveying paths 53Y and 54Y, a two-component developer G composed of a carrier and toner is accommodated. The agitating / conveying path 54Y communicates with the toner receiving port 43Y through an opening formed thereabove.

  The developing unit 5Y configured as described above operates as follows.

  The developing sleeve of the developer carrying member 51Y rotates in the direction of the arrow in FIG. The developer G carried on the developer carrier 51Y by the magnetic field formed by the magnet moves on the developer carrier 51Y as the developing sleeve rotates.

  Here, the developer G in the developing unit 5Y is adjusted so that the ratio of toner in the developer (toner concentration) falls within a predetermined range. Specifically, according to the toner consumption in the developing unit 5Y, the toner stored in the toner container 32Y (see FIG. 1) is replenished into the agitation transport path 54Y via a toner replenishing device (not shown).

  Thereafter, the toner replenished in the stirring and conveying path 54Y circulates in the stirring and conveying path 53Y and the stirring and conveying path 54Y while being mixed and stirred together with the developer G by the stirring and conveying member 55Ya and the stirring and conveying member 55Yb (FIG. 2). In the vertical direction of the paper). The toner in the developer G is adsorbed to the carrier by frictional charging with the carrier and is carried on the developer carrier 51Y together with the carrier by the magnetic force formed on the developer carrier 51Y.

  The developer G carried on the developer carrier 51Y is conveyed in the direction of the arrow in FIG. 2 and reaches the position of the layer thickness regulating member 52Y. The developer G on the developer carrier 51Y is conveyed to a position (development region) facing the latent image carrier 1Y after the developer amount is adjusted to an appropriate amount at this position. The toner is attracted to the latent image formed on the latent image carrier 1Y by the electric field formed in the development area. Thereafter, the developer G remaining on the developer carrier 51Y reaches the upper portion of the developer accommodating portion as the developing sleeve rotates, and is detached from the developer carrier 51Y at this position.

<Drive gear train>
Next, the agitating / conveying members 55Ya and 55Yb and the agitating / conveying member gears 62Ya ′ and 62Yb ′ will be described with reference to FIGS. 3 and 4, only one of the pair of stirring and conveying members 55Ya and 55Yb and the stirring and conveying member gears 62Ya ′ and 62Yb ′ is illustrated.

  The agitating / conveying members 55Ya and 55Yb and the agitating / conveying member gears 62Ya 'and 62Yb' do not have a D-shaped portion as in the conventional example, and can be independently rotated within a certain range. As shown in FIG. 3, protrusions 65Ya ′ and 65Yb ′ are provided at the ends of the agitating and conveying members 55Ya and 55Yb, and these protruding parts 65Ya ′ and 65Yb ′ are provided with the agitating and conveying member gear 62Ya shown in FIG. The fan-shaped grooves 64Ya 'and 64Yb' provided at ', 62Yb' are assembled so as to enter. The groove portions 64Ya 'and 64Yb' are connected to cylindrical through holes formed in the agitating / conveying member gears 62Ya 'and 62Yb', and the fan-shaped angle is 90 degrees with respect to the center of the through hole. . At the time of image formation, the agitating / conveying member gears 62Ya ′ and 62Yb ′ rotate in the direction of the arrow shown in FIG. 5. At this time, the inner walls of the groove portions 64Ya ′ and 64Yb ′ of the gears come into contact with the protruding portions 65Ya ′ and 65Yb ′. In order to transmit the driving force, the agitating / conveying members 55Ya and 55Yb rotate in synchronization with the agitating / conveying member gears 62Ya ′ and 62Yb ′.

  In reverse rotation control during non-image formation, the agitating / conveying member gears 62Ya 'and 62Yb' rotate (reversely rotate) in the direction of FIG. In the present embodiment, the reverse rotation angle is about 30 °. Therefore, the fan-shaped grooves 64Ya 'and 64Yb' provided with an angle greater than the reverse rotation angle provide the stirring and conveying member gears 62Ya 'and 62Yb' and the protrusions 65Ya 'and 65Yb of the stirring and conveying members 55Ya and 55Yb. Do not touch '. The angle of the fan shape may be an arbitrary angle such as 30 ° to 90 ° as long as it is equal to or greater than the reverse rotation angle, but is determined depending on the strength of the stirring and conveying member gears 62Ya ′ and 62Yb ′. Become. FIG. 7 shows an arrangement state of the drive unit including the agitating / conveying member gears 62Ya 'and 62Yb' that reversely rotate during non-image formation.

  As described above, in the developing device according to the present embodiment, only the agitating / conveying member gears 62Ya ′ and 62Yb ′ are reversely rotated and the agitating / conveying members 55Ya and 55Yb are reversely rotated even when the reverse rotation control is performed at the time of non-image formation. There is nothing to do. Therefore, the movement in the longitudinal direction of the agitating and conveying members 55Ya and 55Yb due to the thrust in the reverse direction as described above is suppressed, and the problem of the posture change of the seal member 64Y (see FIG. 13) as before does not occur, and always. Sealing performance is always kept good.

  FIG. 8 shows another embodiment. As described above, the agitating / conveying members 55Ya and 55Yb do not reversely rotate even when the reverse rotation control is entered, and the sealing performance is kept good. However, when the image forming operation is started again, the agitating / conveying member gear 62Ya is entered. Due to the rotation of ', 62Yb', the inner walls of the groove portions 64Ya ', 64Yb' of the gears vigorously collide with the protruding portions 65Ya ', 65Yb' at the ends of the stationary agitating and conveying members 55Ya, 55Yb. The resulting defective image may occur. In order to solve such a problem, in the present embodiment, shock absorbers 67Ya ′ and 67Yb ′ such as foamed PUR and low resilience sheet as shown in FIG. It is provided on the 65Yb ′ side surface. By providing such shock absorbers 67Ya 'and 67Yb', generation of a defective image due to the above-described collision shock can be suppressed, and a good image can be provided. In this example, shock absorbers 67Ya ′ and 67Yb ′ are provided on the side surfaces of the protrusions 65Ya ′ and 65Yb ′ of the agitating and conveying members 55Ya and 55Yb. It may be provided.

  FIG. 9 shows an example in which an image forming unit or the like is accommodated in a casing to form a process cartridge. That is, the process cartridge 81 integrally accommodates the latent image carrier 1Y, the cleaning unit 2Y, the charging unit 4Y, the developing unit 5Y, and the image forming unit 6Y in the casing 82. Such a process cartridge 81 can be attached to and detached from the image forming apparatus main body 100 as described above. When the process cartridge 81 is attached to the image forming apparatus main body 100 by replacement or the like, a part of the process cartridge 81 is removed from the casing 82 as shown in FIG. The appearing latent image carrier 1Y is positioned so as to be in contact with the intermediate transfer belt 8, and the formed image can be primarily transferred onto the intermediate transfer belt 8 sandwiched between the primary transfer bias roller 9Y. is there.

  The above-described embodiment is merely a preferred example, and the present invention includes various other appropriate embodiments within the scope described in the claims. For example, although the fan-shaped shape is adopted as the grooves 64Ya ′ and 64Yb ′ provided in the stirring and conveying member gears 62Ya ′ and 62Yb ′, the stirring and conveying member gears 62Ya ′ and 62Yb ′ and the stirring and conveying member 55Ya are controlled by reverse rotation control. As long as the same effect can be obtained with a shape that does not contact the projections 65Ya ′ and 65Yb ′ of 55Yb, other shapes may be used. The same applies to the shapes of the protrusions 65Ya 'and 65Yb' provided at the ends of the stirring and conveying members 55Ya and 55Yb.

1Y, 1M, 1C, 1K Latent image carrier 2Y (2M, 2C, 2K) Cleaning unit 4Y (4M, 4C, 4K) Charging unit 5Y (5M, 5C, 5K) Developing unit (developing device)
6Y, 6M, 6C, 6K Image forming unit 7 Exposure unit 8 Intermediate transfer belt 9Y, 9M, 9C, 9K Primary transfer bias roller 12 Secondary transfer backup roller 15 Intermediate transfer unit 19 Secondary transfer roller 20 Fixing unit 26 Paper feed Part 31 Toner container housing part 32Y, 32M, 32C, 32K Toner container 51Y (51M, 51C, 51K) Developer carrier 52Y (52M, 52C, 52K) Layer thickness regulating member 53Y (53M, 53C, 53K) Stirring conveyance path 54Y (54M, 54C, 54K) Agitating and conveying paths 55Ya and 55Yb Agitating and conveying members 57Y and 58Y Housing 59Y Drive input gear 60Y Developer carrier gear 61Y Idler gears 62Ya 'and 62Yb' Agitating and conveying member gears 64Ya 'and 64Yb' Groove 65Ya ' , 65Yb 'Protrusion 67Ya', 67Yb 'Shock absorber 81 pro Scan cartridge 82 casing 100 an image forming apparatus main body P transfer material (transfer paper)

Japanese Patent No. 3515849

Claims (7)

To a developing region facing a latent image carrier on which a latent image is formed, and a magnet fixedly supported on a developer container containing developer, and supported on the outer periphery of the magnet so as to be rotatable in both forward and reverse directions. A developer carrier having a developing sleeve for conveying the developer adsorbed on the surface;
A developer carrier gear fixed to an end of the developer carrier and rotated by external drive transmission;
An agitating and conveying member for agitating and conveying the developer sent from the developing sleeve in the longitudinal direction;
An agitating and conveying member gear fixed to an end of the agitating and conveying member and rotated in conjunction with the developer carrier gear by external drive transmission ;
In a developing device that is controlled so that the developer carrier rotates in reverse during non-image formation,
A protrusion is provided at the end of the agitating and conveying member, and a groove that fits with the protruding portion with play in the rotation direction is provided in the agitating and conveying member gear, and in the reverse rotation control by the fitting of the protruding and groove. A developing device configured to prevent the stirring and conveying member from rotating in reverse.   A pair of the agitating / conveying members are arranged so that the two-component developer can be circulated while being agitated in the longitudinal direction and conveyed, and an agitating / conveying member gear is fixed to each end of the agitating / conveying member. The developing device according to claim 1, wherein the agitating / conveying member gears are arranged directly or via meshing with an idler gear, and any one of the agitating / conveying member gears is driven by external drive transmission.   The developing device according to claim 1, wherein the groove is provided in a fan shape at an angle in a range of 30 ° to 90 ° in the rotation direction.   4. The developing device according to claim 1, wherein an impact absorbing material is installed on a side surface of the protruding portion of the stirring and conveying member or an inner wall of the groove portion of the stirring and conveying member gear.   The developing device according to claim 1, wherein the external drive transmission is performed by a drive input gear that meshes with a stirring and conveying member gear.   A process cartridge comprising the developing device according to claim 1.   An image forming apparatus comprising the developing device according to claim 1 or the process cartridge according to claim 6.

Images