JP6555576B2 - Driving device and image forming apparatus - Google Patents

Description

  The present invention relates to a drive device and an image forming apparatus.

  An image forming apparatus in a copying machine, a printer, a facsimile machine, or a complex machine thereof is provided with a large number of driving devices for an image forming operation, and is used for operations of a photoconductor and a developing device.

  Patent Document 1 discloses an internal gear that meshes with a motor gear provided on an output shaft of a drive motor, an external gear that is provided coaxially with the internal gear and rotates integrally with the internal gear, and an external gear. A drive device having an output gear that meshes and outputs a driving force to a driven transmission member is described.

  In recent years, drive devices provided in image forming apparatuses tend to reduce the number of drive motors provided in the drive device for cost reduction, and drive force is transmitted from one drive motor to a plurality of driven transmission members. A configuration is often used. For example, a plurality of timing belts are wound around the output gear meshing with the external gear that rotates integrally with the internal gear as described above, and each of the plurality of driven transmission members at positions away from the external gear is provided. A drive train is configured to transmit drive force via each timing belt. However, the output gear that is wound around a plurality of timing belts is subjected to driving torque by driving transmission to each driven transmission member, and the tension of each timing belt is applied, resulting in a high load and poor durability. Problems arise.

In order to solve the above-described problems, the present invention provides a drive transmission having a drive source having an output gear, an internal tooth portion that directly meshes with the output gear, and an external tooth portion provided coaxially with the internal tooth portion. A drive device comprising a member and first to third development output gears that are drivingly connected to the drive transmission member and output a drive force to the first to third development rollers. The idler gear and the second development output gear are directly meshed with the tooth portion, and the first timing belt is stretched between the pulley portion of the idler gear and the pulley portion of the first development output gear. The second timing belt is stretched between the pulley portion of the second development output gear and the pulley portion of the third development output gear .

  As described above, according to the present invention, there is an excellent effect that the durability of the output gear that outputs the driving force to the driven transmission member can be improved.

FIG. 2 is a schematic diagram of a color development driving device according to Configuration Example 1. 1 is a schematic configuration diagram of a printer according to an embodiment. Expansion explanatory drawing of one of four process units. FIG. 10 is a diagram illustrating an example of a drive train in a conventional color development drive device. 2 is a top view of a color development driving device according to Configuration Example 1. FIG. 1 is a schematic perspective view of a color development driving device according to Configuration Example 1. FIG. FIG. 7 is a cross-sectional view of the color development driving device shown in FIG. 6. FIG. 6 is a schematic perspective view of a color development driving device according to Configuration Example 2. FIG. 10 is a schematic diagram of a color development driving device according to Configuration Example 2. FIG. 10 is a schematic diagram of a color development driving device according to Configuration Example 3.

  An embodiment of an electrophotographic printer (hereinafter simply referred to as “printer 100”) will be described below as an image forming apparatus to which the present invention is applied. First, a basic configuration of the printer 100 according to the present embodiment will be described. FIG. 2 is a schematic configuration diagram of the printer 100 according to the present embodiment. The printer 100 includes four process units 26K, 26C, 26M, and 26Y for forming black, cyan, magenta, and yellow (hereinafter referred to as K, C, M, and Y) toner images. These use different colors of K, C, M, and Y toners as image forming substances, but otherwise have the same configuration and are replaced when the lifetime is reached.

  FIG. 3 is an enlarged explanatory view of one of the four process units 26K, 26C, 26M, and 26Y. Since the four process units 26K, 26C, 26M, and 26Y are the same except that the color of the toner to be used is different, the subscripts (K, C, M, and Y) indicating the color of the toner to be used are omitted in FIG. doing. As shown in FIG. 3, the process unit 26 includes a drum-shaped photosensitive member 24 as a latent image carrier, a photosensitive member cleaning device 83, a static eliminator and a charging device 25, and a developing unit 23. It has. The process unit 26 as an image forming unit can be attached to and detached from the main body of the printer 100 so that consumable parts can be replaced at a time.

  The charging device 25 uniformly charges the surface of the photoreceptor 24 that is driven to rotate clockwise in the drawing by the driving unit. The uniformly charged surface of the photosensitive member 24 is exposed and scanned by the laser beam L emitted from the optical writing unit 27 to carry an electrostatic latent image for each color. This electrostatic latent image is developed into a toner image by the developing unit 23 using toner. Then, primary transfer is performed on the intermediate transfer belt 22.

  The photoconductor cleaning device 83 removes transfer residual toner adhering to the surface of the photoconductor 24 after the primary transfer process. Further, the static eliminator neutralizes residual charges on the photoreceptor 24 after cleaning. By this charge removal, the surface of the photoconductor 24 is initialized and prepared for the next image formation.

  The developing unit 23 includes a vertically long hopper portion 86 that stores toner as a developer, and a developing portion 87. An agitator 88 that is rotated by driving means, a toner supply roller 80 as a developer supplying member that is rotated and driven by driving means below the vertical direction, and the like are disposed in a hopper 86 serving as a developer containing portion. Has been. The toner in the hopper 86 moves toward the toner supply roller 80 by its own weight while being agitated by the rotational drive of the agitator 88. The toner supply roller 80 has a metal cored bar and a roller part made of foamed resin or the like coated on the surface of the metal core. The toner accumulated on the lower side of the hopper 86 is applied to the surface of the roller part. Rotate while adhering.

  In the developing unit 87 of the developing unit 23, a developing roller 81 that rotates while contacting the photoreceptor 24 and the toner supply roller 80, a thinning blade 82 that contacts the tip of the developing roller 81, and the like are disposed. Yes. The toner attached to the toner supply roller 80 in the hopper 86 is supplied to the surface of the development roller 81 at a contact portion between the development roller 81 and the toner supply roller 80. When the supplied toner passes through the contact position between the developing roller 81 and the thinning blade 82 as the developing roller 81 rotates, the layer thickness on the surface of the developing roller 81 is regulated. Then, the toner after the regulation of the layer thickness adheres to the electrostatic latent image on the surface of the photosensitive member 24 in the developing region which is a contact portion between the developing roller 81 and the photosensitive member 24. By this adhesion, the electrostatic latent image is developed into a toner image.

  Such toner images are formed in the process units 26K, 26C, 26M, and 26Y, and toner images of the respective colors are formed on the respective photoreceptors 24 of the process units 26K, 26C, 26M, and 26Y.

  As shown in FIG. 2, an optical writing unit 27 is disposed above the four process units 26K, 26C, 26M, and 26Y in the vertical direction. The optical writing unit 27 as a latent image writing device optically scans each of the photosensitive members 24 in the four process units 26K, 26C, 26M, and 26Y with a laser light L emitted from a laser diode based on image information. . By this optical scanning, an electrostatic latent image for each color is formed on the photoreceptor 24. In such a configuration, the optical writing unit 27 and the four process units 26K, 26C, 26M, and 26Y make K, C, M, and Y toners as visible images of different colors on the four photosensitive members 24, respectively. It functions as an image forming means for forming an image.

  The optical writing unit 27 irradiates the photoconductor 24 through a plurality of optical lenses and mirrors while polarizing the laser light L emitted from the light source by a polygon mirror rotated by a polygon motor in the main scanning direction. . As the optical writing unit 27, an optical writing unit that performs optical writing with LED light emitted from a plurality of LEDs of the LED array may be employed.

  Below the four process units 26K, 26C, 26M, and 26Y, a transfer unit 75 is disposed as a belt device that moves the endless intermediate transfer belt 22 endlessly in a counterclockwise direction while stretching. Has been. In addition to the intermediate transfer belt 22, the transfer unit 75 includes a driving roller 76, a tension roller 20, four primary transfer rollers 74K, 74C, 74M, and 74Y, a secondary transfer roller 21, a belt cleaning device 71, a cleaning backup roller 72, and the like. It has.

  The intermediate transfer belt 22, which is a belt member and a transfer belt, is stretched by a driving roller 76, a tension roller 20, a cleaning backup roller 72, and four primary transfer rollers 74K, 74C, 74M, and 74Y disposed inside the loop. It is built. Then, it is moved endlessly in the same direction by the rotational force of the driving roller 76 that is driven to rotate counterclockwise in the drawing by the driving means.

  The four primary transfer rollers 74K, 74C, 74M, and 74Y sandwich the intermediate transfer belt 22 that is moved endlessly in this manner between the photoreceptors 24K, 24C, 24M, and 24Y. By this sandwiching, four primary transfer nips for K, C, M, and Y where the front surface of the intermediate transfer belt 22 and the photoreceptors 24K, 24C, 24M, and 24Y abut are formed.

  A primary transfer bias is applied to the primary transfer rollers 74K, 74C, 74M, and 74Y by a transfer bias power source. As a result, a transfer electric field is formed between the electrostatic latent images on the photoreceptors 24K, 24C, 24M, and 24Y and the primary transfer rollers 74K, 74C, 74M, and 74Y. Instead of the primary transfer roller 74, a transfer charger or a transfer brush may be employed.

  The Y color toner image formed on the surface of the photoreceptor 24Y of the process unit 26Y enters the above-described primary transfer nip for Y as the photoreceptor 24Y rotates. In the primary transfer nip for Y, the Y color toner image is primarily transferred from the photoreceptor 24Y onto the intermediate transfer belt 22 by the action of the transfer electric field and nip pressure. The intermediate transfer belt 22 onto which the Y-color toner image has been primarily transferred in this way passes through the primary transfer nips for M, C, and K along with the endless movement thereof, so that the image on the photoreceptors 24M, 24C, and 24K. The M, C, and K color toner images are primarily transferred onto the Y color toner image in a superimposed manner. A four-color toner image is formed on the intermediate transfer belt 22 by the primary transfer of the superposition.

  The secondary transfer roller 21 of the transfer unit 75 is disposed outside the loop of the intermediate transfer belt 22 and sandwiches the intermediate transfer belt 22 between the tension roller 20 inside the loop. By this sandwiching, a secondary transfer nip where the front surface of the intermediate transfer belt 22 and the secondary transfer roller 21 abut is formed. A secondary transfer bias is applied to the secondary transfer roller 21 by a transfer bias power source. By this application, a secondary transfer electric field is formed between the secondary transfer roller 21 and the tension roller 20 connected to the ground.

  Below the transfer unit 75 in the vertical direction, a paper feed cassette 41 that accommodates a plurality of recording papers stacked in a bundle is slidably attached to the housing of the printer 100. In the paper feed cassette 41, a paper feed roller 42 is brought into contact with the top recording paper in a bundle of paper, and the recording paper is rotated counterclockwise in the figure at a predetermined timing. Send it out toward the paper feed path.

  Near the end of the paper feed path, a registration roller pair 43 composed of two registration rollers is disposed. The registration roller pair 43 stops the rotation of both rollers as soon as a recording sheet serving as a recording member fed from the sheet feeding cassette 41 is sandwiched between the rollers. Then, rotation driving is restarted at a timing at which the sandwiched recording paper can be synchronized with the four-color toner image on the intermediate transfer belt 22 in the above-described secondary transfer nip, and the recording paper is sent out toward the secondary transfer nip.

  The four-color toner image on the intermediate transfer belt 22 that is in close contact with the recording paper at the secondary transfer nip is secondarily transferred onto the recording paper under the influence of the secondary transfer electric field and nip pressure, and combined with the white color of the recording paper. A full color toner image is obtained. The recording paper having the full-color toner image formed on the surface in this way is separated from the secondary transfer roller 21 and the intermediate transfer belt 22 by the curvature when passing through the secondary transfer nip. Then, the toner is sent to a fixing device 40 as a fixing unit via a post-transfer conveyance path.

  The fixing device 40 is provided with a fixing roller 45 including a heat source 45a such as a halogen lamp, and a pressure roller 47 that rotates while contacting the fixing roller 45 with a predetermined pressure. A fixing nip is formed by the pressure roller 47. The recording paper fed into the fixing device 40 is sandwiched between the fixing nips such that the unfixed toner image carrying surface is in close contact with the fixing roller 45. Then, the toner in the toner image is softened by the influence of heating and pressurization, and the full-color image is fixed.

  When the single-sided print mode is set, the recording paper discharged from the fixing device 40 is discharged to the outside as it is. Then, it is stacked on a stack portion constituted by the upper surface of the upper cover 56 of the housing.

  Note that the untransferred toner that has not been transferred to the recording paper adheres to the intermediate transfer belt 22 after passing through the secondary transfer nip. This is cleaned from the belt surface by a belt cleaning device 71 in contact with the front surface of the intermediate transfer belt 22. A cleaning backup roller 72 disposed inside the loop of the intermediate transfer belt 22 backs up the cleaning of the belt by the belt cleaning device 71 from the inside of the loop.

  FIG. 4 is a diagram illustrating an example of a drive train in a conventional color development drive device. In the color development driving device that drives the development rollers 81C, 81M, 81Y provided in the development units 23C, 23M, 23Y of cyan, magenta, and yellow by one color development motor 160, the following transmission method is used. Take as an example.

  The motor gear 163 of the color developing motor 160, which is a driving source, meshes with the internal tooth portion 155a of the developing internal tooth external gear integrated gear 155, and the external tooth portion 155b of the developing internal tooth external gear integrated gear 155 is the drive output gear 152M. Are engaged. Then, the driving force from the color developing motor 160 is transmitted to the driving output gear 152M via the developing internal and external gear integrated gear 155. Further, two timing belts, a first timing belt 153 applied to the drive output gear 152Y and a second timing belt 154 applied to the drive output gear 152C, are applied to the drive output gear 152M. Then, the driving force from the driving output gear 152M is transmitted to the driving output gear 152C and the driving output gear 152Y via the first timing belt 153 and the second timing belt 154 for driving. In this case, the driving output gear 152M is applied with torque from the developing internal / external teeth integrated gear 155 and torque from the three developing rollers 81C, 81M, 81Y of C, M, Y, and two timings. Tension is also generated by the belt, resulting in high load. The durability of the drive output gear 152M is reduced by the amount of tension applied by the two timing belts as compared with the developing internal / outer teeth integrated gear 155 to which the same torque is applied.

[Configuration example 1]
FIG. 5 is a top view of the color development driving device 150 according to the first configuration example. FIG. 6 is a schematic perspective view of the color development driving device 150 according to the first configuration example. FIG. 7 is a cross-sectional view of the color development driving device 150 shown in FIG. The motor gear 51a of the color photoconductor motor 51 meshes with the photoconductor gear 53C and the photoconductor gear 53M, and connects the photoconductor drive shaft 53aC of the photoconductor gear 53C and the photoconductor drive shaft 53aM of the photoconductor gear 53M. Via the photoconductor 24C and the photoconductor 24M. Further, the driving force is transmitted from the photosensitive member gear 53M to the photosensitive member gear 53Y through the idler gear 52i, and the driving force is transmitted to the photosensitive member 24Y through the photosensitive member driving shaft 53a of the photosensitive member gear 53Y. Further, as shown in FIG. 5, the photoconductor gears 53C, 53M, and 53Y are external gears having a diameter larger than that of the photoconductors 24C, 24M, and 24Y, and the influence of the gear accuracy on the image is reduced. Yes.

  The color development drive device 150 includes a color development motor 160 and a bracket 162 made of a sheet metal that holds a drive transmission member such as a gear for transmitting the drive force of the color development motor 160. The color developing motor 160 is attached to a surface of the bracket 162 opposite to the surface facing the developing roller so that the motor shaft 160a passes therethrough. On the opposite surface of the bracket 162 facing the developing roller, a developing internal / external tooth integrated gear 155, idler gear pulley 151, Y, M, C driving output gears 152Y, 152M, 152C are held.

  The drive output gears 152Y, 152M, and 152C for each color have the same shape, and include a driven gear portion 152a, a pulley portion 152b, and a drive side coupling portion 152c. The idler gear pulley 151 has an idler gear portion 151a and a pulley portion 151b. The developing internal and external gear integrated gear 155, the idler gear pulley 151, and the driving output gears 152 </ b> Y, 152 </ b> M, and 152 </ b> C for each color are rotatably supported by driving pins fixed to the bracket 162. Thus, by making the drive output gears 152Y, 152M, and 152C of the respective colors have the same shape, it is possible to share components and reduce component management costs. The drive output gear 152C and the drive output gear 152Y may be configured to include only the pulley portion 152b and the drive side coupling portion 152c.

  The first timing belt 153 is wound around the pulley portion 151b of the idler gear pulley 151 and the pulley portion 152bY of the drive output gear 152Y. The second timing belt 154 is wound around the pulley portion 152bM of the M-color drive output gear 152M and the pulley portion 152bC of the C-color drive output gear 152C. As the first timing belt 153 and the second timing belt 154, a toothed belt, a V belt, or the like can be used.

  The developing internal tooth external gear integrated gear 155 has an internal tooth portion 155a and an external tooth portion 155b, and the internal tooth portion 155a meshes with the motor gear 163 of the color developing motor 160. The idler gear portion 151a of the idler gear pulley 151 and the driven gear portion 152a of the M driving output gear 152M are meshed with the external tooth portion 155b of the developing internal gear external gear integrated gear 155.

  The driving force of the color developing motor 160 is transmitted to the developing roller 81Y via the developing internal / external teeth integral gear 155, idler gear pulley 151, first timing belt 153, and driving output gear 152Y, and the developing roller 81Y Rotating drive. The driving force of the color developing motor 160 is transmitted to the developing roller 81M via the developing internal / outer teeth integrated gear 155 and the drive output gear 152M, and the developing roller 81M is rotationally driven. The driving force of the color developing motor 160 is transmitted to the developing roller 81C via the developing internal and external teeth integrated gear 155, the driving output gear 152M, the second timing belt 154, and the driving output gear 152C, and the developing roller 81C Rotating drive.

  Further, by setting the gear meshing with the motor gear 163 of the color developing motor 160 to be the internal tooth portion 155a of the developing internal tooth external gear integrated gear 155, the meshing rate with the motor gear 163 can be increased, and rotation unevenness, noise, Generation of vibration can be suppressed.

  FIG. 1 is a schematic diagram of a color development driving device 150 according to the first configuration example. The drive output gear 152M and the idler gear pulley 151 are meshed with the external tooth portion 155b of the developing internal tooth external gear integrated gear 155, respectively. The first timing belt 153 is wound around the idler gear pulley 151 and the drive output gear 152Y, and the second timing belt 154 is wound around the drive output gear 152M and the drive output gear 152C. Thereby, the idler gear pulley 151 and the drive output gear 152M can divide the developing roller rotation torque and the tension applied by the first timing belt 153 and the second timing belt 154. Therefore, the load applied to the drive output gear 152M is reduced accordingly, and the durability of the drive output gear 152M can be improved.

[Configuration example 2]
FIG. 8 is a schematic perspective view of a color development driving device 150 according to Configuration Example 2. FIG. 9 is a schematic diagram of a color development driving device 150 according to Configuration Example 2. In this configuration example, the first tightner 156 comes into contact with the outer peripheral belt surface of the first timing belt 153 wound around the pulley portion 151b of the idler gear pulley 151 and the pulley portion 152bY of the drive output gear 152Y. A tension is applied to one timing belt 153. Further, the second timing belt 154 is in contact with the outer peripheral belt surface of the second timing belt 154 wound around the pulley portion 152bM of the drive output gear 152M and the pulley portion 152bC of the drive output gear 152C. Tension is applied to the belt 154. Further, the tension from the first timing belt 153 and the second timing belt 154 can be maintained constant by providing the first tighter 156 and the second tighter 157 so as to be swingable on the bracket 162 and the like.

  Also, by providing the first timing belt 153 and the second timing belt 154 with the first tightner 156 and the second tightner 157, the winding angle of each timing belt with respect to the idler gear pulley 151 and each drive output gear 152 is increased. Jump can be suppressed.

[Configuration example 3]
FIG. 10 is a schematic diagram of a color development driving device 150 according to Configuration Example 3. In this configuration example, the drive output gear 152M, the idler gear pulley 151, and the idler gear pulley 158 are engaged with the external tooth portion 155b of the developing internal tooth external gear integrated gear 155, respectively. The first timing belt 153 is wound around the idler gear pulley 151 and the drive output gear 152Y, and the second timing belt 154 is wound around the idler gear pulley 158 and the drive output gear 152C. By using the same number of idler gear pulleys as the number of timing belts as in this configuration example, the tension from the first timing belt 153 and the second timing belt 154 is not applied to the drive output gear 152M. The load is reduced and a highly durable drive train is possible.

What was demonstrated above is an example, and there exists an effect peculiar for every following aspect.
(Aspect A)
A drive motor such as a color developing motor 160, an internal gear such as an internal gear portion 155a that meshes with a motor gear such as a motor gear 163 provided on an output shaft such as a motor shaft 160a of the drive motor, and a coaxial with the internal gear An external gear such as an external tooth portion 155b that rotates integrally with the internal gear and a drive output gear that meshes with the external gear and outputs a driving force to a driven transmission member such as the developing roller 81M. In a driving device such as a color development driving device 150 provided with an output gear such as 152M, a plurality of gears including the output gear mesh with the external gear, and at least the output gear of the plurality of gears. A belt member such as a first timing belt 153 is stretched around one of the remaining gears such as a different idler gear pulley 151, and the output gear is Power is configured to transmit the driving force to the other of the driven transmission member, such as a different developing roller 81Y and the driven transmission member to be output.
In (Aspect A), the driving torque of the plurality of driven transmission members and the tension of the belt member are generated by a plurality of gears meshed with the external gear including the gear on which the belt member is stretched and the output gear. The load can be divided. Therefore, the load applied to the output gear is reduced and the output gear is more durable than the case where a load such as the drive torque of a plurality of driven transmission members and the tension of the belt member is applied only to the output gear. Can be improved.
(Aspect B)
In (Aspect A), the internal gear is made of resin. According to this, as described in the above embodiment, it is possible to improve the quietness.
(Aspect C)
In (Aspect A) or (Aspect B), a tension applying member such as a first tightener 156 that contacts the belt surface of the belt member and applies tension to the belt member is provided. According to this, as described in the above embodiment, the risk of tooth skipping can be reduced.
(Aspect D)
In (Aspect C), the tension applying member is swingably provided. According to this, as described in the above embodiment, the tension of the belt member can be made constant, leading to high durability.
(Aspect E)
In any one of (Aspect A) to (Aspect D), the belt member is a toothed belt, so that silence can be improved.
(Aspect F)
The image forming apparatus such as the printer 100 includes an image forming unit such as a process unit 26 that forms an image, and a driving device such as the color development driving device 150 according to any one of (Aspect A) to (Aspect E). . According to this, as described in the above embodiment, while reducing the number of drive motors and reducing the cost, the drive is transmitted to the developing roller 81 and the like, so that the durability of the gear is improved and the time is improved. An image forming operation can be executed.

DESCRIPTION OF SYMBOLS 10 Photoconductor unit 20 Tension roller 21 Secondary transfer roller 22 Intermediate transfer belt 23 Development unit 24 Photoconductor 25 Charging device 26 Process unit 27 Optical writing unit 40 Fixing device 41 Paper feed cassette 42 Paper feed roller 43 Registration roller pair 45 Fixing Roller 45a Heat source 47 Pressure roller 51 Color photoreceptor motor 51a Motor gear 52i Idler gear 53 Photoreceptor gear 53a Photoreceptor drive shaft 56 Upper cover 71 Belt cleaning device 72 Cleaning backup roller 74 Primary transfer roller 75 Transfer unit 76 Drive roller 80 Toner Supply roller 81 Developing roller 82 Thin layer blade 83 Photoconductor cleaning device 86 Hopper portion 87 Developing portion 88 Agitator 100 Printer 150 Color development driving device 15 Idler gear pulley 151a idler gear portion 151b pulley portion 152 drive output gear 152a driven gear portion 152b pulley portion 152c driving side coupling portion 153 first timing belt 154 second timing belt 155 developing internal tooth external gear integral gear 155a internal tooth portion 155b outside Tooth 156 First tightner 157 Second tighter 158 Idler gear pulley 160 Color developing motor 160a Motor shaft 162 Bracket 163 Motor gear

JP 2014-111983 A

Claims (6)

  A drive source with an output gear;
A drive transmission member having an inner tooth portion directly meshing with the output gear and an outer tooth portion provided coaxially with the inner tooth portion;
In the driving device comprising the first to third development output gears that are drivingly connected to the drive transmission member and output driving force to the first to third developing rollers,
The idler gear and the second development output gear are directly meshed with the outer teeth of the drive transmission member,
A first timing belt is stretched between the pulley portion of the idler gear and the pulley portion of the first development output gear;
2. A driving device, wherein a second timing belt is stretched between a pulley portion of the second development output gear and a pulley portion of the third development output gear.   A drive source with an output gear;
A drive transmission member having an inner tooth portion directly meshing with the output gear and an outer tooth portion provided coaxially with the inner tooth portion;
In the driving device comprising the first to third development output gears that are drivingly connected to the drive transmission member and output driving force to the first to third developing rollers,
The first idler gear, the second idler gear, and the second development output gear are directly meshed with the outer teeth of the drive transmission member,
A first timing belt is stretched between the pulley portion of the first idler gear and the pulley portion of the first development output gear;
And a second timing belt stretched between a pulley portion of the second idler gear and a pulley portion of the third development output gear. The drive device according to claim 1 or 2,
A second drive source different from the drive source;
Further comprising first to third latent image carrier driving output gears for outputting a driving force to the first to third latent image carriers.
The first and second latent image carrier drive output gears directly mesh with the output gear provided in the second drive source,
The third latent image carrier drive output gear is drivingly connected to the second latent image carrier drive output gear . In the drive device according to any one of claims 1 to 3,
Further comprising first and second tension applying means for applying tension to the first and second timing belts;
The driving device according to claim 1, wherein the first and second tension applying means are in contact with the first and second timing belts in opposite directions .   The drive device according to claim 4, wherein
The drive device characterized in that the first and second tension applying means are provided on the loose side of the first and second timing belts. An image forming apparatus comprising the driving apparatus as claimed in 請 Motomeko 1 to 5.

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