JP2009058735A - Connecting device, connecting method, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting device capable of reducing the number of parts and simplifying assembly work; a connecting method; and an image forming apparatus. <P>SOLUTION: The opening end of a female side joint in at least one of constant velocity joints is composed to be elastically deformable in the connecting device with two units of the constant velocity joints serially installed in the axial direction. Further, a falling out preventing projection integrated with the female side joint, which projects from the opening end part of an inner periphery surface on outer race part and/or an outer periphery surface on inner race part of an annular space on the female side joint and preventing a male side joint from falling out of the female side joint. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a connecting device, a connecting method, and an image forming apparatus.

  Conventionally, a constant velocity joint is known as one of drive transmission mechanisms for transmitting rotational torque of a drive shaft of an automobile to an axle. The constant velocity joint can transmit a driving force between them in the rotational direction at a constant velocity while allowing a deviation angle between the driving shaft on the driving side and the driven shaft on the driven side that are aligned in the axial direction. .

  As a constant velocity joint, for example, a triball joint as described in Patent Document 1 is generally known. The tri-ball joint includes a ball non-holding member and a ball holding member that are aligned in the axial direction. The ball non-holding member has an annular space that is open at one end, and an outer groove is formed as a track groove that extends in the axial direction on the outer wall surface of the annular space and is arranged at intervals of 120 ° in the circumferential direction. Has been. In addition, an inner groove serving as a track groove is formed on the inner wall surface of the annular space so as to face the outer groove while extending in the axial direction. On the other hand, the ball holding member is formed so that ball holding holes are arranged at intervals of 120 ° in the circumferential direction on the hollow cylindrical peripheral wall inserted into the annular space of the ball non-holding member, Holding the ball in the ball holding hole. The ball holding member is inserted into the annular space of the ball non-holding member so that these balls are engaged with the inner groove and the outer groove of the ball non-holding member. In this state, when either the ball non-holding member or the ball holding member rotates on the driving side, the rotational force is transmitted to the other through the plurality of balls engaged with the inner and outer grooves. The

Further, in Patent Documents 2 and 3, the triball joints described above are arranged in series in the axial direction, and even when there is a misalignment between the drive shaft and the driven shaft, the rotation of the drive shaft is the same as the driven shaft. A coupling device capable of transmitting at high speed is described.
Japanese Patent Application Laid-Open No. H10-228561 also describes a connecting device in which triball joints are arranged in series in the axial direction for connecting the output shaft of the photosensitive member driving motor and the photosensitive member shaft of the image forming apparatus.

Japanese Patent Publication No. 52-34699 JP 2006-194415 A JP 2006-97758 A JP 2006-163232 A

  However, in the connecting devices described in Patent Documents 2 to 4, after a part of the ball holding member is inserted into the annular space of the ball non-holding member, the ball holding member is prevented from coming off near the opening end of the annular space of the ball non-holding member. A ring is inserted to prevent the ball holding member from coming out of the ball non-holding member. For this reason, there is a problem that the number of parts is increased by the number of retaining rings and the part management cost is increased. In addition, since a part of the ball holding member is inserted into the annular space of the ball non-holding member and a retaining ring is fitted in the vicinity of the opening end of the annular space of the ball non-holding member, the coupling device is assembled. There is a problem that becomes complicated.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a coupling device, a coupling method, and an image forming apparatus capable of reducing the number of parts and simplifying the assembly work. Is to provide.

In order to achieve the above object, a first aspect of the present invention is a coupling device that couples a driven shaft for transmitting a driving force to a rotating body and a driving shaft that receives a driving force from a driving source and rotates. A non-ball-holding member having an annular space with one end opened, and a plurality of track grooves extending in the axial direction at equal intervals in the circumferential direction on at least one of an outer wall surface and an inner wall surface of the annular space; Two constant velocity joints having a ball holding member that is incorporated in the annular space of the ball non-holding member and holds a ball that slides along the track groove formed in the ball non-holding member. Arranged in series and protrudes from the open end of the outer wall surface and / or inner wall surface of the annular space of the ball non-holding member of at least one constant velocity joint, and the ball holding member comes out of the ball non-holding member And a non-ball holding member made of the same material, and the opening end of the non-ball holding portion is configured to be elastically deformable. It is characterized by.
The invention according to claim 2 is the connecting device according to claim 1, wherein the annular space between the ball holding member of at least one constant velocity joint and the outer wall surface of the non-ball holding member and / or the ball holding member A ring-shaped elastic member is inserted into an annular space between the inner wall surface of the ball non-holding member.
According to a third aspect of the present invention, in the connecting device according to the second aspect, the hardness of the elastic member is lower than the hardness of the material forming the ball non-holding member.
According to a fourth aspect of the present invention, in the coupling device according to any one of the first to third aspects, the constant velocity joint on the driven shaft side is a first constant velocity joint, and the constant velocity joint on the drive shaft side is a second constant velocity joint. When a joint is used, the driving shaft side member of the first constant velocity joint and the driven shaft side member of the second constant velocity joint are integrated.
According to a fifth aspect of the present invention, after a rotating body and a driven shaft for transmitting a driving force to the rotating body, the unit detachable from the apparatus main body is positioned with respect to the apparatus main body. A connection method for connecting the driven shaft and a drive shaft that is rotationally driven by receiving a driving force from a drive source provided in the apparatus main body, wherein the driven shaft and the drive shaft are connected to each other. 4. Any one of the four connecting devices is used.
According to a sixth aspect of the present invention, there is provided a unit having a rotating body and a driven shaft for transmitting a driving force to the rotating body, the unit being detachable from the apparatus body, and the unit being attached to the apparatus body. In the image forming apparatus comprising: a connecting unit that connects the driven shaft and a driving shaft that is rotationally driven by receiving a driving force from a driving source provided in the apparatus body in the positioned state; The connecting device according to any one of claims 1 to 4 is used.

According to the first to sixth aspects of the present invention, the retaining protrusion for preventing the ball holding member from coming off the ball non-holding member is an integral part of the ball non-holding member. The cost can be reduced, and the cost of parts management can be reduced.
In addition, since the opening end of the ball non-holding member is elastically deformable, even if the ball non-holding member has a retaining protrusion, a part of the ball holding member is not held as follows. It can be inserted into the annular space of the member. That is, when a part of the ball holding member is inserted into the annular space of the non-ball holding member, the ball held by the ball holding member hits the retaining protrusion. At this time, if the ball holding member is strongly pushed into the ball non-holding member side, the opening end of the ball non-holding member is elastically deformed in the direction of expanding the diameter. Accordingly, the ball held by the ball holding member is engaged with the track groove of the ball non-holding member, and a part of the ball holding portion is inserted into the annular space of the ball non-holding member.
In this way, the coupling device can be assembled simply by pushing the ball holding member strongly toward the ball non-holding member, so that after the ball holding member is inserted into the ball non-holding member, the annular space of the ball non-holding member is opened. Compared with the case where a retaining ring is fitted near the end, the number of assembling steps can be reduced, and the assembling work can be simplified.

Hereinafter, an embodiment of an electrophotographic printer (hereinafter simply referred to as a printer) will be described as an image forming apparatus to which the present invention is applied.
First, the basic configuration of the printer will be described. FIG. 1 is a schematic configuration diagram showing the printer. In the figure, the printer includes four process cartridges 1Y, C, M, and K for generating toner images of yellow, cyan, magenta, and black (hereinafter referred to as Y, C, M, and K). Yes. These use Y, C, M, and K toners of different colors as image forming substances for forming an image. The other configurations are the same, and are replaced when the lifetime is reached. In the following description, since the process cartridges 1Y, 1C, 1M, and 1K have the same configuration, the reference symbols Y, C, M, and K for color classification are omitted.
As shown in FIG. 2, the process cartridge 1 contains a drum-shaped photosensitive member 2 as an image carrier, a drum cleaning unit 3, a charging unit 4, a developing unit 5, a lubricant application unit 6, and the like in a frame (not shown). ing. The process cartridge 1 can be attached to and detached from the printer body, so that consumable parts can be replaced at a time.

  The charging unit 4 uniformly charges the surface of the photoreceptor 2 that is rotated clockwise in the drawing by a driving unit (not shown). In the figure, the charging roller 4a, which is a rotating member that is driven to rotate counterclockwise in the drawing while a charging bias is applied by a power source (not shown), is not in contact with the photosensitive member 2 to uniformly charge the photosensitive member 2. The non-contact charging roller type charging unit 4 is shown. As the charging unit 4, other than the above, a scorotron method, a corotron method, a contact roller method, or the like can be used.

As the charging bias applied to the contact type and non-contact type charging roller 4a, there are a type in which alternating current is superimposed on direct current, and a method in which only direct current is applied. The charging bias that superimposes the alternating current on the direct current in the contact type charging roller 4a is such that the surface potential of the charging roller 4a remains constant even if the resistance value of the charging roller 4a changes due to environmental changes by controlling the alternating current to a constant current. There is a merit that is not affected. However, the cost of the power supply device becomes high, and AC high frequency sound is a problem. On the other hand, in the non-contact charging roller 4a, the surface of the photosensitive member cannot be uniformly charged due to the influence of the gap fluctuation between the photosensitive member 2 and the charging roller 4a with the charging bias that superimposes the alternating current on the direct current. , The image is uneven. For this reason, a charging bias correcting means corresponding to the gap fluctuation is required.
The charging roller 4a can be driven by a method of rotating with the photosensitive member 2 or a method of obtaining a driving force from a driving source for driving the photosensitive member 2 through a gear or the like. In the case of a low-speed machine, a method of rotating with the photosensitive member 2 is generally used. The latter method is common for devices that require high speed and high image quality.

  In the figure, a charging roller cleaner 4b for cleaning the surface of the charging roller 4a is provided. Thereby, it is possible to prevent the photosensitive member 2 from being charged to the target potential due to dirt adhering to the charging roller 4a. As a result, abnormal images due to poor charging can be suppressed. The charging roller cleaner 4b is generally composed of melanin, and is configured to rotate with the charging roller 4a.

  The developing unit 5 as developing means has a first agent accommodating portion 5e in which a first conveying screw 5a is disposed. Further, it also has a second agent storage portion 5f in which a toner concentration sensor 5c composed of a magnetic permeability sensor, a second transport screw 5b, a developing roll 5g, a doctor blade 5d, and the like are disposed. In these two agent storage portions, a developer (not shown) composed of a magnetic carrier and a negatively chargeable toner is included. The first transport screw 5a is driven to rotate by a driving unit (not shown), thereby transporting the developer in the first agent container 5e from the front side to the back side in the drawing. And it penetrates into the 2nd agent accommodating part 5f through the communication port which is not shown in the partition wall between the 1st agent accommodating part 5e and the 2nd agent accommodating part 5f. The second transport screw 5b in the second agent container 5f is rotated by a driving means (not shown), thereby transporting the developer from the back side to the front side in the drawing. The developer concentration in the middle of conveyance is detected by a toner concentration sensor 5c fixed to the bottom of the second agent storage portion 5f. In the upper part of the second conveying screw 5b for conveying the developer in this way in the figure, a developing roll 5g that includes the magnet roller 5i in the developing sleeve 5h that is driven to rotate counterclockwise in the figure is disposed in parallel. ing. The developer conveyed by the second conveying screw 5b is pumped up to the surface of the developing sleeve 5h by the magnetic force generated by the magnet roller 5i. Then, after the layer thickness is regulated by a doctor blade 5d arranged so as to maintain a predetermined gap from the developing sleeve 5h, it is conveyed to a developing region facing the photosensitive member 2 and is electrostatically charged on the photosensitive member 2. Toner adheres to the latent image. By this adhesion, a Y toner image is formed on the photoreceptor 2. The developer that has consumed toner by the development is returned to the second conveying screw 5b as the developing sleeve 5h of the developing roll 5g rotates. And if it conveys to the near end in a figure, it will return in the 1st agent accommodating part 5e through the communication port which is not shown in figure.

  The detection result of the magnetic permeability of the developer by the toner concentration sensor 5c is sent to a control unit (not shown) as a voltage signal. Since the magnetic permeability of the developer has a correlation with the toner concentration of the developer, the toner concentration sensor 5c outputs a voltage having a value corresponding to the toner concentration. The control unit includes a RAM, in which data of Vtref, which is a target value of the output voltage from the toner density sensor 5c, is stored. For the developing unit 5, the value of the output voltage from the toner density sensor 5c is compared with Vtref, and a toner supply device (not shown) is driven for a time corresponding to the comparison result. By this driving, an appropriate amount of toner is supplied from the first agent container 5e to the developer whose toner density has been reduced by consuming the toner during development. For this reason, the toner concentration of the developer in the second agent container 5e is maintained within a predetermined range.

  The cleaning unit 3 removes untransferred toner remaining on the surface of the photoconductor 2 without being transferred from the surface of the photoconductor 2. The cleaning unit 3 is provided with a cleaning blade 3a that is a blade member that contacts the surface of the photoreceptor in the counter direction. Further, the cleaning unit 3 includes a collection unit 3b that collects the transfer residual toner on the surface of the photoreceptor 2 removed by the cleaning blade 3a. The collection unit 3b includes a conveyance auger 3c that conveys the toner collected by the collection unit to a waste toner bottle (not shown).

  Transfer residual toner on the surface of the photoreceptor 2 is removed by the cleaning blade 3a. The transfer residual toner collected at the tip of the cleaning blade 3a falls to the collection unit 3b. Then, the toner is transported as waste toner to a waste toner bottle (not shown) by the transport auger 3c and stored therein. The waste toner stored in the waste toner bottle in this way is collected by a service person or the like. Note that the transfer residual toner collected in the collection unit 3b may be conveyed to the developing unit 5 as recycled toner and used again for development.

  The lubricant application unit 6 as a lubricant application means applies a lubricant to the surface of the photoreceptor 2 to reduce the coefficient of friction on the surface of the photoreceptor 2. The lubricant is applied to the surface of the photoreceptor 2 by molding the lubricant into a solid form to form a solid lubricant 6a, and pressing the solid lubricant 6a against the fur brush 6c that is rotated by the pressure spring 6b, thereby fur brush. It is applied to the photoreceptor 2 via 6c. As the lubricant, ZnSt (zinc stearate) is most commonly used. The fur brush 6c is made of insulating PET, conductive PET, acrylic fiber, or the like. The lubricant applied to the surface of the photosensitive member is fixed to the surface of the photosensitive member with a uniform thickness by the lubricant application blade 6d. By applying a lubricant to the surface of the photoconductor 2, filming of the photoconductor 2 can be prevented.

  As shown in FIG. 1, an optical writing unit 20 is disposed below the process cartridges 1Y, 1C, 1M, and 1K in the drawing. The optical writing unit 20 serving as a latent image forming unit irradiates each photoconductor in each of the process cartridges 1Y, 1C, 1M, and 1K with a laser beam L emitted based on the image information. As a result, electrostatic latent images for Y, C, M, and K are formed on the photoreceptors 2Y, 2C, 2M, and 2K. The optical writing unit 20 deflects the laser light L emitted from the light source by the polygon mirror 21 that is rotationally driven by a motor, and passes through the photosensitive members 2Y, 2C, 2M, and 2K via a plurality of optical lenses and mirrors. Is irradiated.

  A first paper feed cassette 31 and a second paper feed cassette 32 are arranged on the lower side of the optical writing unit 20 in the drawing so as to overlap in the vertical direction. Each of these paper feed cassettes accommodates a plurality of transfer papers P as recording bodies in a stacked state, and the uppermost transfer paper P includes a first paper feed roller 31a, The second paper feed rollers 32a are in contact with each other. When the first paper feed roller 31a is driven to rotate counterclockwise in the figure by driving means (not shown), the uppermost transfer paper P in the first paper feed cassette 31 is vertically oriented on the right side of the cassette in the figure. The paper is discharged toward the paper feed path 33 arranged so as to extend. Further, when the second paper feed roller 32 a is driven to rotate counterclockwise in the figure by a driving means (not shown), the uppermost transfer paper P in the second paper feed cassette 32 is directed toward the paper feed path 33. Discharged. A plurality of transport roller pairs 34 are arranged in the paper feed path 33, and the transfer paper P sent to the paper feed path 33 is sandwiched between the rollers of the transport roller pair 34, while the paper feed path 33. 33 is conveyed from the lower side to the upper side in the figure.

  A registration roller pair 35 is disposed at the end of the paper feed path 33. The registration roller pair 35 temporarily stops the rotation of both rollers as soon as the transfer paper P sent from the transport roller pair 34 is sandwiched between the rollers. Then, the transfer paper P is sent out toward a later-described secondary transfer nip at an appropriate timing.

  Above each of the process cartridges 1Y, 1C, 1M, and 1K, there is disposed a transfer unit 40 that endlessly moves counterclockwise in the drawing while stretching an intermediate transfer belt 41 that is an intermediate transfer member. The transfer unit 40 serving as transfer means includes an intermediate transfer belt 41, a belt cleaning unit 42, a first bracket 43, a second bracket 44, and the like. Further, four primary transfer rollers 45Y, 45C, 45M, 45K, a secondary transfer backup roller 46, a drive roller 47, an auxiliary roller 48, a tension roller 49, and the like are also provided. The intermediate transfer belt 41 is endlessly moved counterclockwise in the figure by the rotational driving of the driving roller 47 while being stretched by these eight rollers. The four primary transfer rollers 45Y, 45C, 45C, 45M, 45K, and 45K sandwich the intermediate transfer belt 41 that is moved endlessly in this manner from the photoreceptors 2Y, 2C, 2M, and 2K, thereby forming primary transfer nips. ing. Then, a transfer bias having a polarity opposite to that of the toner (for example, plus) is applied to the back surface (loop inner peripheral surface) of the intermediate transfer belt 41. The intermediate transfer belt 41 sequentially passes through the primary transfer nips for Y, C, M, and K along with the endless movement thereof, and on the surface of the photoreceptor 2Y, C, M, K on the front surface. The Y, C, M, and K toner images are superimposed and primarily transferred. As a result, a four-color superimposed toner image (hereinafter referred to as a four-color toner image) is formed on the intermediate transfer belt 41.

  The secondary transfer backup roller 46 sandwiches the intermediate transfer belt 41 with the secondary transfer roller 50 disposed outside the loop of the intermediate transfer belt 41 to form a secondary transfer nip. The registration roller pair 35 described above sends the transfer paper P sandwiched between the rollers toward the secondary transfer nip at a timing at which the transfer paper P can be synchronized with the four-color toner image on the intermediate transfer belt 41. The four-color toner image on the intermediate transfer belt 41 is affected by the secondary transfer electric field formed between the secondary transfer roller 50 to which the secondary transfer bias is applied and the secondary transfer backup roller 46, and the influence of the nip pressure. The secondary transfer is batch-transferred onto the transfer paper P in the secondary transfer nip. Then, combined with the white color of the transfer paper P, a full color toner image is obtained.

  Transfer residual toner that has not been transferred to the transfer paper P adheres to the intermediate transfer belt 41 after passing through the secondary transfer nip. This is cleaned by the belt cleaning unit 42.

  A fixing unit 60 including a pressure roller 61 and a fixing belt unit 62 is disposed above the secondary transfer nip in the drawing. The fixing belt unit 62 of the fixing unit 60 moves the fixing belt 64 endlessly in the counterclockwise direction in the drawing while being stretched by the heating roller 63, the tension roller 65, and the driving roller 66. The heating roller 63 includes a heat source such as a halogen lamp, and heats the fixing belt 64 from the back side. A pressure roller 61 that is driven to rotate clockwise in the drawing is in contact with the surface of the fixing belt 64 that is heated in this manner from the front side. Thereby, a fixing nip where the pressure roller 61 and the fixing belt 64 abut is formed.

  The transfer paper P that has passed through the secondary transfer nip is separated from the intermediate transfer belt 41 and then sent into the fixing unit 60. Then, in the process of being conveyed from the lower side to the upper side in the figure while being sandwiched by the fixing nip, the full-color toner image is fixed by being heated or pressed by the fixing belt 64.

  The transfer sheet P subjected to the fixing process in this manner is discharged outside the apparatus after passing between the rollers of the discharge roller pair 67. A stack unit 68 is formed on the upper surface of the housing of the printer main body, and the transfer sheets P discharged to the outside by the pair of discharge rollers 67 are sequentially stacked on the stack unit 68.

  Above the transfer unit 40, four toner cartridges 120Y, 120C, 120M, and 120K that store Y, C, M, and K toners are disposed. The Y, C, M, and K toners in the toner cartridges 120Y, 120C, 120M, and 120K are appropriately supplied to the developing units of the process cartridges 1Y, 1C, 1M, and 1K, respectively. These toner cartridges 120Y, 120C, 120M, and 120K can be attached to and detached from the printer main body independently of the process cartridges 1Y, 1C, 1M, and 1K.

  In the printer having the above-described configuration, toner image formation for forming a toner image on the transfer paper P, which is a recording medium, by combining the four process cartridges 1Y, 1C, 1M, 1K, the optical writing unit 20, the transfer unit 40, and the like. Means are configured.

3A is a front view when the process cartridge 1 is viewed from the back side of the main body of the image forming apparatus, and FIG. 3B is a perspective view. 4 is a schematic configuration diagram when the process cartridge 1 is mounted on the printer main body, and FIG. 5 is a schematic configuration diagram before the process cartridge 1 is mounted on the printer main body.
As shown in FIG. 4, a front side plate 18 and a back side plate 11 are provided outside the respective end portions in the longitudinal direction of the process cartridge 1. The face plates 11 and 18 rotatably support the drum shaft 2a, which is a support shaft of the photosensitive member 2, and the developing roller shaft 5j of the developing roller 5g provided in the developing unit 5, so that the photosensitive member 2 and the developing roller 5g are supported. Maintain a constant development gap in between. That is, the drum shaft 2 a of the photoreceptor 2 is rotatably fitted to the face plates 11 and 18 via the bearings 15 and 17. The developing roller shaft 5j of the developing roller 5g is also rotatably fitted to the face plates 11 and 18 via bearings 16 and 19, respectively. As a result, the developing unit 5 as the driven unit and the photosensitive member 2 are assembled together.

  Further, as shown in FIGS. 3A and 3B, the back side plate 11 is formed with a secondary reference hole 13 made of a long hole, and the secondary reference hole 13 is fixed to the developing unit 5. The secondary reference pin 5m is fitted. Similarly, a secondary reference hole made of a long hole is formed in the front side plate 18, and a secondary reference pin fixed to the developing unit 5 is fitted in the secondary reference hole. As described above, the secondary reference pin is fitted into the secondary reference hole formed in each of the face plates 11 and 18, so that the developing unit 5 is prohibited from rotating around the central axis of the developing roller 5g.

  As described above, the photosensitive member 2 and the developing roller 5g are correctly positioned and connected to each other to constitute an integral process cartridge 1. In addition, the distance between the central axis of the photoreceptor 2 and the central axis of the developing roller 5g is correctly regulated by the face plates 11 and 18. As a result, when the photoconductor 2 and the developing roller 5g are arranged so as to face each other with a small gap as shown in the illustrated example, the gap is correctly maintained, and the photoconductor 2 has a high quality. A clear toner image can be developed. Further, when the photosensitive member 2 and the developing roller 5g are configured to contact each other and face each other, the contact pressure is correctly regulated so that a high-quality toner image is developed on the photosensitive member 2. Can do.

  Further, as shown in FIG. 5, the cartridge side reference pin 14 which is a cartridge side reference reference fitting portion is formed on the back side surface plate 11. A driven side coupling 93a is fixed to the back end of the drum shaft 2a.

FIG. 6 is a main part schematic perspective view showing a drive transmission part of the developing unit 5 as a unit transmission mechanism.
As shown in the figure, a first gear 140 is attached to the shaft of the developing roller 5g, and an idler gear 142 attached to a rotation shaft rotatably supported by a frame (not shown) is attached to the first gear 140. I'm engaged. The idler gear 142 meshes with a second gear 143 attached to the shaft of the transport screw 5b. Since the developing roller 5g as a rotating body has the largest torque in the developing unit 5, it is preferable to attach the connecting means 70 to the shaft of the developing roller 5g. This is because the developing roller torque is applied to unit transmission mechanisms such as the first gear 140, the idler gear 142, and the second gear 143 when the connecting means 70 is attached to the conveying screw shaft. On the other hand, when the connecting means 70 is attached to the developing roller shaft, the torque of the conveying screw is applied to the unit transmission mechanism. Since the developing roller has a larger torque than the conveying screw, the load on the unit transmission mechanism is smaller when the torque of the conveying screw is applied to the unit transmission mechanism than when the torque of the developing roller is applied to the unit transmission mechanism. . Therefore, attaching the connecting means 70 to the developing roller shaft requires less load on the unit transmission mechanism than attaching to the conveying screw shaft, and can extend the life of the unit transmission mechanism.

  As shown in FIGS. 4 and 5, a driving device 80 is fixed to the main body side plate 91 facing the back side plate 11 of the process cartridge 1 provided in the printer main body. The driving device 80 includes a holding plate 89, a photosensitive member driving motor 81 serving as a photosensitive member driving source, a developing driving motor 94 serving as a developing unit driving source, a driving transmission mechanism unit 96 serving as a driving transmission mechanism, and a connecting unit 70. have.

  The holding plate 89 is attached to the main body side plate 91 by screwing or the like. A photosensitive member drive motor 81 and a development drive motor 94 are attached to the holding plate 89. A motor shaft 81 a of the photosensitive member driving motor 81 is rotatably fitted to the main body side plate 91 via the bearing 90 and passes through the main body side plate 91. A driving side coupling 93b is attached to the tip of the motor shaft 81a so as to be movable in the axial direction, and is urged toward the process cartridge by a coil spring 92 wound around the motor shaft 81a. The main body side coupling 93b is appropriately prevented by a pin (not shown) provided on the motor shaft 81a. A motor shaft 94 a of the developing drive motor 94 is rotatably fitted to the main body side plate 91 via a bearing 95.

  In the present embodiment, a driving source for driving the photosensitive member and a driving source for driving the developing roller are separately provided, and the driving force of the photosensitive member driving motor 81 as a driving source for driving the photosensitive member is applied only to the photosensitive member. It is being used. With this configuration, the photoconductor drive motor can rotate the photoconductor 2 with high accuracy without receiving load fluctuations from other drive elements. Of course, the developing roller and the photosensitive member may be driven by one driving source.

The drive transmission mechanism 190 includes a first pulley 86, a drive shaft 82, a second pulley 83, a timing belt 85, an electromagnetic clutch 97, a driven shaft 94b, and a driven gear 99.
The driven shaft 94b is rotatably fitted to the holding plate 89 via the bearing 96, and is rotatably fitted to the main body side plate 91 and the auxiliary support member 88 via the bearing 95. It is supported by the holding plate 89. The drive shaft 82 is supported by the main body side plate 91 and the holding plate 89. Specifically, the drive shaft 82 is rotatably fitted to the holding plate 89 via the bearing 87, and is rotatably fitted to the main body side plate 91 and the auxiliary support member 88 via the bearing 84. The main body side plate 91 and the holding plate 89 are supported. The auxiliary support member 88 is attached to the holding plate 89 by screwing or the like.
A first pulley 86 and a driven gear 99 are fixed to the driven shaft 94b, and the driven gear 99 meshes with a driving gear fixed to the motor shaft 94a of the developing drive motor 94.
A second pulley 83 is fixed to the drive shaft 82 via an electromagnetic clutch 97, and a timing belt 85 is wound around the second pulley 83 and the first pulley 86.

  When the driving force of the developing drive motor 94 is transmitted to the developing roller 5g, the conveying screw 5b, etc., the electromagnetic clutch 97 is turned on and the drive shaft 82 and the second pulley 83 are connected. On the other hand, when the drive shaft 82 and the developing roller shaft 5j are connected by the connecting means 70 including the two sets of constant velocity joints 71 and 72, the electromagnetic clutch 97 is turned off and the drive shaft 82 is connected to the second pulley 83. To be able to rotate freely. Instead of the electromagnetic clutch, the drive shaft 82 and the second pulley 83 are connected in the rotational direction at the time of driving. When the drive shaft 82 rotates in the direction opposite to the rotational direction at the time of driving, the drive shaft 82 is connected. A one-way clutch that releases the connection between the first pulley 83 and the second pulley 83 may be used.

Further, the driving shaft 82 and the developing roller shaft 5j as a driven shaft are connected by a connecting means 70 having two sets of constant velocity joints.
FIG. 7 is a schematic configuration diagram of the connecting means 70.
As shown in the figure, the connecting means 70 includes a first male side joint 711 that is a ball holding member, a second male side joint 721 that is a ball holding member, and a relay member 73. The first male side joint 711 is attached to the back end of the developing roller shaft 5j, and the second male side joint 721 is attached to the end of the drive shaft 82 on the process cartridge side. A first female joint portion 712 that is a non-ball holding portion having an annular space with an opening at the developing roller shaft side end portion is formed at the developing roller shaft side end portion of the relay member 73. In addition, a second female side joint 722 that is a non-ball holding portion having an annular space in which the driving shaft side end is opened is formed at the driving shaft side end.

  The first female side joint portion 712 closes the other end side while opening one end side in the axial direction in the annular space 712d, and the first male side joint 711 is inserted from the opening. That is, in the present embodiment, the first constant velocity joint 71 is formed by the first female side joint portion 712 of the relay member 73 and the first male side joint 711. Further, the second female side joint portion 722 closes the other end side while opening one end side in the axial direction in the annular space 722d, and the second male side joint 721 is inserted from the opening. That is, in the present embodiment, the second constant velocity joint 72 is formed by the second female side joint portion 722 of the relay member 73 and the first male side joint 721.

  In this embodiment, the 1st female side joint which comprises the 1st constant velocity joint 71, and the 2nd female side joint which comprises the 2nd constant velocity joint 72 are each the integrated objects (for example, resin material) which consist of the same material (for example, resin material). Relay member). Thereby, compared with what provides a 1st female side joint and a 2nd female side joint separately, a number of parts can be reduced.

  The constant velocity joint will be described below with reference to FIGS. The first constant velocity joint and the second constant velocity joint have the same configuration, and in the following description, the first constant velocity joint is described as an example. Also, reference numerals in parentheses in FIGS. 8 to 10 are reference numerals of the respective parts of the second constant velocity joint.

FIG. 8 is a cross-sectional view of the first female side joint portion 712 of the relay member 73.
As shown in the drawing, the first female side joint portion 712 includes a cylindrical cup portion having an opening on the developing roller shaft 5j side into which the first male side joint 711 is inserted. The cup portion includes an outer ring portion 712b, an inner ring portion 712c inside thereof, an annular space 712d formed by a gap between the two, an outer groove 712e serving as three track grooves provided on the inner peripheral surface of the outer ring portion 712b, and an inner ring portion. And an inner groove 712f which is three track grooves provided on the outer peripheral surface of 712c.

  The three outer grooves 712e provided on the inner peripheral surface of the outer ring portion 712b are formed to extend in the axial direction of the outer ring portion 712b and to be arranged in a circular direction with a phase difference of 120 [°]. The three inner grooves 712f provided on the outer peripheral surface of the inner ring portion 712c are also formed to extend in the axial direction of the inner ring portion 712c and to be arranged in a circular direction with a phase difference of 120 [°]. The inner groove 712f and the outer groove 712e face each other through the annular space 712d.

  As shown in FIG. 9, a tapered outer groove guide portion 712 h is provided on the opening end side of the outer groove 712 e so as to move away from the center of the axis toward the opening end and the groove width increases. Further, on the opening end side of the inner groove 712f, there is provided a tapered inner groove guide portion 712i that approaches the axial center and increases the groove width toward the opening end. Thus, by providing the guide portions 712h and 712i, the ball 173 can be guided to the annular space 712d in which the inner groove 712f and the outer groove 712e face each other, and the male side joint 711 is inserted into the female side joint 712. Can be easily performed.

  Moreover, the edge part of each inner groove guide part 712i crosses in the opening end of a cup part. With this configuration, when the male side coupling and the female side coupling are assembled, even if the phase between the track groove (the outer groove 712e and the inner groove 712f) and the ball 173 is around 60 °, the ball 173 can be brought into contact with the open end of the inner groove guide portion 712i. Thereby, even if the phase of the ball 173 and the track groove (the inner groove 712f and the outer groove 712e) is around 60 °, a part of the axial force applied to the inner ring portion 712c is rotated by the inner groove guide portion 712i. The force can be converted into a directional force, and the male joint can be rotated relatively smoothly with respect to the female joint. Therefore, the insertion resistance when the ball 173 held by the male joint is inserted into the annular space 712d between the outer groove 712e and the inner groove 712f of the female joint can be reduced, and the ball 173 can be reduced. It can be smoothly inserted into the annular space 712d between the outer groove 712e and the inner groove 712f.

FIG. 10 is a cross-sectional view of the first male side joint. The cross-sectional view of the second male side joint has the same configuration, and the reference numerals of the respective parts of the second male side joint are shown in parentheses.
The distal end side of the male side joint 711 is a cylindrical insertion portion 711a. The insertion portion 711a has three through holes 711b provided in the cylindrical peripheral wall so as to be aligned along the circumferential direction with a phase difference of 120 [°], and a spherical body is formed in each through hole 711b. The ball 173 is held rotatably.

The hole diameter A of the through hole 711 b is larger than the diameter B of the ball 173. In addition, an inner peripheral retaining protrusion 711d protruding from the inner peripheral end of the inner surface of the through hole 711b is provided with a phase difference of 180 °. Further, an outer peripheral retaining protrusion 711c protruding from the outer peripheral end of the inner surface of the through hole 711b is provided with a phase difference of 180 °. The outer peripheral retaining protrusion 711c is provided with a 90 ° phase difference from the inner peripheral retaining protrusion 711d. The outer peripheral retaining protrusion 711c prevents the ball 173 in the through hole 711b from falling off the outer peripheral surface of the insertion portion 711a. Further, the ball 173 in the through hole 711b does not fall off from the inner circumferential surface of the insertion portion 711a by the inner circumferential retaining protrusion 711d. The diameter C of the inscribed circle of the retaining protrusions 711c and 711d is preferably set in the range of 80 to 99% of the diameter B of the ball 173. If it is less than 80%, the retaining projections 711c and 711d protrude too much from the through hole 711b, and the ball 173 cannot be inserted into the through hole 711b. The retaining protrusions 711c and 711d are formed by forcibly removing the mold. However, if the protrusions 711c and 711d protrude too much, the retaining protrusions 711c and 711d may be damaged when the mold is removed after injection molding. For this reason, the diameter C of the inscribed circle of the retaining protrusions 711 c and 711 d is preferably set to 80% or more of the diameter B of the ball 173.
Further, by making the hole diameter A of the through hole 711b larger than the diameter B of the ball 173, the ball 173 can be moved in the radial direction in the through hole 711b. Thereby, when inserting the insertion part 711a of the male side joint 711 into the female side joint 712 annular space 712d, when the ball 173 hits the outer ring part 712b of the female side joint, the ball 173 moves in the axial center direction. Thereby, the insertion part 711a of the male side joint 711 can be smoothly inserted into the annular space 712d of the female side joint 712.

  Further, a tolerance is set so that the distance D from the outer groove 712e to the inner groove 712f is longer than the diameter B of the ball 73. When the distance D from the outer groove 712e to the inner groove 712f is set to the same length as the diameter B of the ball 173, the distance D from the outer groove 712e to the inner groove 712f is greater than the diameter B of the ball 173 due to manufacturing errors. May also become smaller. In particular, in this embodiment, since the female joint is injection-molded with resin, the degree of sinking varies depending on the temperature and humidity conditions during manufacturing, and the distance D from the outer groove 712e to the inner groove 712f is equal to the ball 173. There is a high possibility that it will be smaller than the diameter B. When the distance D from the outer groove 712e to the inner groove 712f is smaller than the diameter B of the ball 173, the sliding resistance of the ball 173 with respect to the outer groove 712e and the inner groove 712f increases. As a result, the outer groove 712e and the inner groove 712f are worn early, and the female side joint 712 reaches the end of its life quickly. If the distance D from the outer groove 712e to the inner groove 712f is smaller than the diameter B of the ball 173, the ball 173 is lightly press-fitted between the grooves, and the ball 173 cannot slide smoothly in the groove. There is a possibility that 5 g cannot be rotated at a constant speed. Furthermore, a so-called creep phenomenon occurs in which a constant load is applied to the inner groove and the outer groove 712e for a long period of time and is greatly deformed, so that the life of the female joint 712e reaches an early stage.

  However, in the present embodiment, the distance D from the outer groove 712e to the inner groove 712f is set so as to be longer than the diameter B of the ball 173, so that the ball 173, the outer groove 712e and the ball 173 A gap is formed between the groove 712f. Thereby, the ball 173 can be prevented from being lightly press-fitted between the grooves, and the sliding resistance of the ball 173 with respect to the outer groove 712e and the inner groove 712f can be reliably suppressed. Therefore, the wear and creep phenomenon of the outer groove 712e and the inner groove 712f can be suppressed, and the life of the female joint 712 can be extended. Further, since the ball 173 can slide smoothly in the groove, the developing roller 5g can be reliably rotated at a constant speed.

  A cylindrical insertion portion 711 a of the first male side joint 711 is inserted into the annular space 712 d in the outer ring portion 712 b of the female side joint portion 712. In this state, the three balls 173 held by the insertion portion 711a of the male side joint 711 are respectively connected to the outer groove 712e provided on the inner peripheral surface of the outer ring portion 712b of the female side joint portion 712 and the inner ring portion 712c. It is sandwiched between inner grooves 712f provided on the outer peripheral surface, and movement in the normal direction is prevented. However, since the inner groove 712f and the outer groove 712e extend in the axial direction, the movement of the ball 173 in the axial direction is allowed.

The second male side joint 721 has the same configuration as the first male side joint 711, and the second female side joint portion of the relay member 73 has the same configuration as the first female side joint portion of the relay member 73. Thus, by making the 2nd male side joint 721 and the 1st male side joint the same structure, parts can be made common and management cost etc. can be held down.
Moreover, the female side joint part engaged with a 1st male side joint is formed in the both ends of the relay member 73 by making the 2nd female side joint part and 1st female side joint part of the relay member 73 into the same structure. Either of the female joints can be done well. Thereby, the relay member 73 can be easily assembled.

  Further, as shown in FIG. 7, the first male joint 711 protrudes from the opening end of the outer ring portion 712 b of the first female joint 712 in order to prevent the first male joint 711 from coming off from the first female joint 712. A retaining protrusion 713 is provided. The retaining protrusion 713 may have a ring shape that is continuous in the circumferential direction. A plurality of outer grooves 712e may be provided at equal intervals in the circumferential direction, such as being provided at the end point on the opening side of the outer groove 712e. When the outer groove 712e is provided at the opening end point, the ball 173 held by the first male joint portion 711 hits the retaining protrusion 713, so that the first male joint portion 711 becomes the first female joint. It is possible to suppress the 712 from falling off. Further, the retaining protrusion 713 may be provided at the opening end of the inner ring portion 712c of the first female side joint 712.

  Thus, by providing the retaining protrusion 713 as a retaining mechanism so that the first male joint does not come off from the first female joint, the first male joint can be It is possible to prevent the relay member from falling out of the 1 female side joint and falling into the apparatus main body. Therefore, as shown in FIG. 5, the first male joint and the relay member 73 are integrally attached to and detached from the process cartridge. That is, in the present embodiment, the second constant velocity joint 72 is interlocked with the attachment / detachment of the process cartridge as a unit, and the second female side joint portion 722 as a ball non-holding member and the second male side joint 721 as a ball holding member. Engagement and separation are performed.

The retaining protrusion 713 is integrated with the first female joint portion 712. By comprising in this way, compared with what makes the 1st female side joint part 712 and another member, a number of parts can be reduced and the cost reduction of an apparatus and part management cost can be reduced.
Further, the outer ring portion 712b is configured to be elastically deformable at the tip, for example, formed of synthetic resin. By configuring in this way, when the first male joint 711 is inserted into the first female joint 712, the so-called snap-fit method in which the open end of the outer ring portion 712b is elastically deformed in the direction of expanding the annular space. Thus, the insertion part 711 a of the first male side joint part 711 can be inserted into the annular space 712 d of the first female side joint 712, and the first male side joint 711 can be assembled to the relay member 73.

  The cylindrical insertion portion 711a of the first male side joint 711 is inserted into the annular space 712d of the first female side joint 712, and the three balls 173 held by itself are inserted into the inner groove 712f within the annular space 712d. And engage with the outer groove 712e. Further, the cylindrical insertion portion 721a of the second male side joint 721 is inserted into the annular space 722d of the second female side joint 722, and the three balls 173 held by itself are contained in the annular space 722d. Engage with the groove 722f and the outer groove 722e. Then, the motor shaft 94a of the developing drive motor 94 rotates, the first pulley 86 fixed to the motor shaft also rotates, and the driving force of the first pulley 86 is transmitted to the second pulley 83 by the timing belt 85. When the drive shaft 82 rotates, the rotational driving force is transmitted to the relay member 73 at a constant speed via the three balls 173 held by the second male side joint 721. Then, the rotational driving force of the relay member is transmitted to the first male side joint 711 at a constant speed via the three balls 173 held by the first male side joint 711. As a result, the developing roller shaft 5j and the developing roller 5g rotate at a constant speed.

  In addition, the example which provided the track groove for engaging the ball | bowl 173 to both the inner peripheral surface of the outer ring 712b (722b) of the female side joint 712 (722) and the outer peripheral surface of the inner ring 712c (722c) was demonstrated. However, the track groove may be formed only in one of them.

  The relay member 73 having the first female side joint part 712 and the second female side joint part 722, and the first and second male side joints 711 and 721 are preferably made of a synthetic resin molded product that can be injection-molded. As long as injection molding is possible, either a thermoplastic resin or a thermosetting resin may be used. Synthetic resins that can be injection-molded include crystalline resins and non-crystalline resins. Any resin may be used, but it is preferable to use a crystalline resin because the amorphous resin has low toughness and abrupt destruction occurs when a torque exceeding an allowable amount is applied. Moreover, it is desirable to use one having relatively high lubrication characteristics. Examples of such synthetic resins include polyacetal (POM), nylon, injection-moldable fluororesin (eg, PFA, FEP, ETFE, etc.), injection-moldable polyimide, polyphenylene sulfide (PPS), wholly aromatic polyester, polyether ether Examples thereof include ketone (PEEK) and polyamideimide. These synthetic resins may be used alone or as a polymer alloy in which two or more types are mixed. Moreover, even if it is a synthetic resin other than these and resin with a comparatively low lubrication characteristic, if it is set as the polymer alloy which mix | blended the synthetic resin mentioned above, it can be used.

  The most suitable synthetic resins are slidable synthetic resins such as POM, nylon, PPS, and PEEK. Examples of nylon include nylon 6, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12, nylon 46, and semi-aromatic nylon having an aromatic ring in the molecular chain. Among them, POM, nylon, and PPS are excellent in heat resistance and slidability and are relatively inexpensive, so that a constant velocity joint with excellent cost performance can be realized. Moreover, PEEK is excellent in mechanical strength and slidability even if it does not contain a reinforcing material or a lubricant. Therefore, a high-performance constant velocity joint can be realized.

  By forming the relay member 73 and the male side joints 711 and 721 from a resin material, the weight of the connecting means 70 can be reduced compared to a configuration in which the relay member 73 and the male side joints 711 and 721 are formed from a metal material. it can. Further, by forming the female side joint portions 712 and 722 and the male side joints 711 and 721 of the relay member with a resin having sliding property, the female side joints 712 and 722 can be connected without filling the annular space with grease. The ball 173 can be smoothly slid along the track groove (inner groove, outer groove). Thereby, an operation sound can also be made small compared with the structure formed with a metal material. Further, even if the ball 173 is formed of a resin having sliding property, the ball 173 can smoothly slide in the track groove. Of course, all of the ball 173, the relay member 73, and the male side joints 711 and 721 may be formed of a slidable resin.

Next, the mounting of the apparatus body of the process cartridge 1 will be described.
In the printer of this embodiment, the process cartridge 1 is attached to the apparatus main body with the drum shaft 2a of the photoreceptor 2 as a main reference and the cartridge sub reference pin 14 which is a cartridge side sub reference fitting portion as a sub reference. At this time, the electromagnetic clutch 97 is turned off so that the drive shaft 82 can freely rotate with respect to the second pulley 83.
As shown in FIGS. 4 and 5, when the process cartridge 1 is attached to the image forming apparatus main body, the driven side coupling 93a, which is a positioned portion attached to the drum shaft 2a, is positioned on the motor main body. The process cartridge 1 is positioned in the radial direction with respect to the apparatus main body by fitting with the drive side coupling 93b which is a positioning portion attached to 81a. Further, the slave reference pin 14 which is a cartridge side slave reference fitting portion protruding from the back side plate 11 is fitted into the positioning hole 98 formed in the main body side plate 91. As a result, the process cartridge 1 is prevented from rotating around the central axis of the photosensitive member 2, and the entire process cartridge 1 is correctly positioned with respect to the apparatus main body.

  Even if the entire process cartridge 1 is correctly positioned with respect to the apparatus main body, the axial center of the developing roller shaft 5j and the axial center of the drive shaft 82 may be displaced in the radial direction due to accumulation of tolerances. In such a case, the ball 173 held in the through hole 721 b of the second male side joint 721 hits the outer groove guide part 722 h and the inner groove guide part 712 i of the second female side joint part 722 of the relay member 73. Further, when the process cartridge 1 is inserted into the apparatus main body, as shown in FIG. 11, the relay member 73 is inclined, and the insertion portion 721 a of the second male joint 721 is an annular space of the second female joint portion 722. 722d.

  Further, when the insertion portion 721a of the second male joint 721 is inserted into the annular space 722d of the second female joint 722, the phase of the ball 173 and the phase of the track grooves (the outer groove 722e and the inner groove 722f) Are different from each other, the ball 173 is guided by the outer groove guide portion 722h and the inner groove guide portion 722i and rotates in conjunction with the movement of the process cartridge 1 in the insertion direction, and the phase of the ball 173 and the track groove ( The phases of the outer groove 722e and the inner groove 722f) are matched. At this time, since the electromagnetic clutch 97 is turned OFF so that the drive shaft 82 can freely rotate with respect to the second pulley 83, the rotational load applied to the second male side joint 721 is only the inertial force of the drive shaft 82. It has become. For this reason, the second male side joint 721 can be easily rotated, the rise in insertion resistance of the process cartridge 1 can be suppressed, and the ball 173 can be guided to the track grooves (the outer groove 722e and the inner groove 722f). .

  Then, there is a phase between the ball 173 and the track groove (the outer groove 722e and the inner groove 722f), and the insertion portion 721a of the second male side joint 721 is inserted into the annular space of the second female side joint portion 722, The three balls 173 held by itself are engaged with the inner groove 722f and the outer groove 722e in the annular space 722d.

  When the developing roller 5g and the conveying screw 5b are driven to rotate, the electromagnetic clutch is turned on and the second pulley 83 and the drive shaft 82 are connected. When the developing drive motor 94 is driven to rotate, the motor shaft 94a rotates, the first pulley 86 fixed to the motor shaft 94a also rotates, and is transmitted to the second pulley 83 via the timing belt 85 to drive. A driving force is transmitted to the shaft 82. The driving force is transmitted to the driving shaft 82, the driving shaft 82 rotates, and is transmitted to the developing roller shaft 5j via the connecting means 70.

In the present embodiment, as shown in FIG. 11, even if an axial misalignment occurs between the drive shaft 82 and the developing roller shaft 5j, the relay member 73 is inclined so that the second male side joint 721 is inserted. The portion 721a can be inserted into the annular space of the second female joint portion 722, and the drive shaft 82 and the developing roller shaft 5j can be connected. Further, as shown in the figure, a deviation angle α is generated between the relay member 73 and the drive shaft 82 and between the relay member 73 and the developing roller shaft 5j. Even if the declination α between the drive shaft 82 and the relay member 73 occurs, the ball 173 held by the second male joint 721 of the second constant velocity joint 72 is caused to move into the inner groove 722f of the second female joint 722. By sliding in the annular space between the outer groove 722e and the outer groove 722e, the rotation of the drive shaft can be transmitted at a constant speed.
In addition, even if the deflection angle α between the relay member 73 and the developing roller shaft 5j occurs, the ball 173 held by the first male joint 711 of the first constant velocity joint 71 is changed to the first female joint portion 712. By sliding in the annular space between the inner groove 712f and the outer groove 712e in the axial direction, rotation can be transmitted at a constant speed.

  As described above, even when the declination α occurs between the relay member 73 and the drive shaft 82 and between the relay member 73 and the developing roller shaft 5j, the first constant velocity joint 71 and the second constant velocity joint 72 The rotation of the drive shaft can be transmitted to the developing roller shaft 5j at a constant speed. As a result, the developing roller 5g can be driven to rotate at a constant speed without increasing the mounting accuracy and the component accuracy so that the shaft center does not deviate between the drive shaft 82 and the developing roller shaft 5j. Abnormal images such as unevenness can be suppressed. Therefore, it is possible to suppress abnormal images such as density unevenness while suppressing manufacturing costs and component costs.

  In order to remove the process cartridge 1 from the printer body, a front door (not shown) is opened and the process cartridge 1 is pulled out to the front side. At this time, the connecting means 70 is separated from the second male joint and the second female joint portion of the second constant velocity joint so that the first constant velocity joint and the second female joint portion (the first male joint and the first joint) are separated. The relay member is taken out of the printer main body together with the process cartridge 1. As described above, in the present embodiment, the second constant velocity joint is engaged and separated by attaching and detaching the process cartridge, thereby connecting the drive shaft and the developing roller shaft. Therefore, the number of parts can be reduced and the cost of the apparatus can be reduced as compared with the case where a member for connecting the drive shaft and the developing roller shaft is provided separately from the two sets of constant velocity joints. Become.

  Further, the photosensitive member 2 and the developing unit 5 can be separated by removing the face plates 11 and 18 from the photosensitive member 2 and the developing unit 5 after taking the process cartridge 1 out of the printer main body.

  The process cartridge 1 is provided with a guide groove (not shown), and the apparatus body is provided with a guide rail (not shown). The process cartridge 1 is pulled out toward the front side or pushed into the back side. When the guide groove fits into the guide rail, it slides along the guide rail.

Further, the first male side joint and the first female side joint may be engaged and separated in conjunction with the attachment / detachment of the process cartridge. However, the relay member having the first female side joint portion and the second female side joint portion so as to engage and separate the second male side joint and the second female side joint in conjunction with the attachment and detachment of the process cartridge. It is preferable to be able to attach and detach the process cartridge together with the process cartridge.
Since the female joint portions 712 and 722 have a larger sliding amount with the ball 173 than the male joints 711 and 721, the wear progresses faster than the male joints 711 and 721, and the life is reached early. . For this reason, a relay member is a member exchanged most frequently in a connection means. When the first male joint and the first female joint are engaged and separated in conjunction with the attachment / detachment of the process cartridge, the relay member remains in the apparatus main body, so the relay member of the apparatus main body is removed. Therefore, a new relay member is attached in the apparatus main body, and the workability of replacing the relay member is poor.
On the other hand, when the relay member having the first female side joint portion and the second female side joint portion is made detachable from the apparatus main body together with the process cartridge 1, the relay member 73 is replaced by removing the process cartridge 1 from the apparatus main body. Since it can be performed, the exchange workability can be improved. Therefore, compared to the case where the first male side joint and the first female side joint are engaged and separated in conjunction with the attachment and detachment of the process cartridge, and the relay member is left in the apparatus main body, the relay member 73. Can be easily exchanged.

  In this embodiment, the electromagnetic clutch 97 is provided in the drive transmission mechanism 190 of the driving device 80. However, an electromagnetic clutch may be provided in the drive transmission of the developing unit 5 shown in FIG. In this case, the first gear 140 is attached to the developing roller shaft 5j via an electromagnetic clutch. When the second male joint 721 attached to the drive shaft 82 is inserted into the second female joint of the relay member 73, the electromagnetic clutch is turned off to release the connection between the first gear 140 and the developing roller shaft 5j. As a result, when the drive shaft 82 and the developing roller shaft 5j are connected, the torque of the conveying screw 5b is not applied to the developing roller shaft, and the developing roller shaft can be easily rotated. Therefore, when the phase of the ball 173 held by the second male side joint and the track groove of the second female side joint portion is shifted, the second female side joint portion 722 easily rotates, and the ball 173 and the track groove And the phase is matched. Therefore, it is possible to guide the ball 173 to the track groove while suppressing an increase in the insertion resistance of the process cartridge 1.

  In addition, as shown in FIG. 12A, the connecting means 70 uses the first female joint 712 of the first constant velocity joint 71 as a member attached to the driving shaft side tip of the developing roller shaft 5j, and develops the driving shaft 82. A member attached to the roller side end is a second female side joint 722 of the second constant velocity joint 72. And the structure which made the relay member 73 the 1st male side joint 711 and the 2nd male side joint 721 integral. Further, as shown in FIG. 12B, a member attached to the driving shaft side tip of the developing roller shaft 5j is a first female joint 712 of the first constant velocity joint 71, and the developing roller side end portion of the driving shaft 82 is disposed on the developing roller side end portion. A member to be attached is a second male joint 721 of the second constant velocity joint 72. The relay member 73 may have a configuration in which the first male side joint 711 and the second female side joint 722 are integrated. Further, as shown in FIG. 12C, a member attached to the driving shaft side tip of the developing roller shaft 5j is a first male side joint 711 of the first constant velocity joint 71, and the developing roller side end portion of the driving shaft 82 is disposed on the developing roller side end portion. A member to be attached is a second female side joint 722 of the second constant velocity joint 72. The relay member 73 may have a configuration in which the first female joint 712 and the second male joint 721 are integrated.

  As the connecting means 70, the relay member 73 is formed by integrating the first female side joint 712 and the second female side joint 722 shown in FIG. 7, and the first member shown in FIG. It is preferable that the male side joint 711 and the second male side joint 721 are formed as a single body. In the case where the configuration of the first constant velocity joint 71 and the configuration of the second constant velocity joint 71 are the same, the members attached to the drive shaft 82 (in FIG. 7, male side joints 711, 721, FIG. ), The female joints 712 and 722) can be used in common, and the management cost can be reduced. Moreover, since it is not necessary to consider the attachment direction of the relay member 73, the attachment of the relay member 73 becomes easy.

  As shown in FIG. 13, the drive shaft side member (in FIG. 13, the first female side joint 712) of the first constant velocity joint 71 is attached to the developing roller shaft side end of the connecting shaft 75, and the second constant velocity joint 71 is attached. As a configuration in which the developing roller shaft side member of the joint 72 (in FIG. 13, the second female side joint 722) is attached to the driving side end of the connecting shaft 75, the driving shaft side member of the first constant velocity joint (in FIG. 13, The developing roller shaft side member (in FIG. 13, the second female side joint 722) of the first female side joint 712) and the second constant velocity joint may not be integrated.

  Further, as shown in FIG. 14B, when the process cartridge 1 is attached to the apparatus main body, the relay member 73 may be largely inclined due to its own weight. Normally, the axial misalignment between the drive shaft 82 and the developing roller shaft 5j is slight, and as shown in FIG. 14B, when the process cartridge 1 is attached to the apparatus main body, the relay member 73 is largely inclined by its own weight. The second male joint 721 cannot be inserted into the second female joint 722.

  Therefore, as shown in FIG. 14 (A), the first male side joint portion 711 and the first female side of the first constant velocity joint 71 that is not engaged and separated in conjunction with the attachment and detachment of the process cartridge 1. A ring-shaped elastic member 730 such as rubber or sponge is inserted between the inner peripheral surface of the outer ring portion 712b of the joint portion 712. In the example shown in FIG. 14A, a notch 711d is provided on the outer peripheral surface of the tip of the first male side joint portion 711, and the notch 711d and the inner peripheral surface of the outer ring portion 712b of the first female side joint 712 are provided. A ring-shaped elastic member 730 is inserted therebetween. The elastic member 730 may be attached to the cutout portion of the first male side joint portion 711 or may be attached to the inner peripheral surface of the outer ring portion 712b of the first female side joint 712. Moreover, you may insert the ring-shaped elastic member 730 between the internal peripheral surface of the front-end | tip part of the 1st male side joint 711, and the outer peripheral surface of the inner ring part 712c of a 1st female side joint. Further, the elastic member 730 may be inserted between the open end of the inner ring portion 712 c of the first female side joint 712 and the inner peripheral surface of the first male side joint 711. Further, the elastic member 730 may be inserted between the opening end of the outer ring portion 712 b of the first female side joint 712 and the outer peripheral surface of the first male side joint 711.

  Further, the hardness of the elastic member 730 is made lower than the hardness of the material forming the first female joint 712.

  Thus, between the outer peripheral surface of the insertion portion 711a of the first male side joint portion 711 and the inner peripheral surface of the outer ring portion 712b of the first female side joint 712, or within the insertion portion 711a of the first male side joint 711 By inserting the elastic member 730 between the peripheral surface and the outer peripheral surface of the inner ring portion 712c of the first female joint 712, the relay member 73 is prevented from being inclined by its own weight due to the elastic force of the elastic member 730. As a result, when the second male side joint portion 721 of the relay member 73 is inserted into the second female side joint 722 attached to the drive shaft 82, the relay member 73 is greatly inclined, and the second male side joint portion 721 is It is possible to prevent the insertion portion 721a from being inserted into the annular space 722d of the second female joint 722.

  In addition, the hardness of the elastic member 730 is lower than the hardness of the material forming the first female joint 712 and is sufficiently soft, so that the axis of the developing roller shaft 5j and the axis of the drive shaft 82 are displaced in the radial direction. In this state, when the insertion portion 721a of the second male side joint portion 721 is inserted into the annular space 722d of the female side joint 722, the relay member 73 is easily inclined. As a result, the insertion part 721a of the second male side joint 721 can be incorporated into the annular space 722d of the second female side joint part 722.

  In FIG. 14A, a retaining protrusion 713 is provided at a portion other than the end point on the opening side of the outer groove 712e. In this case, a step portion 711e is provided in the insertion portion 711a of the first male side joint portion 711. When the first male joint portion 711 tries to come out from the first female joint 712, the stepped portion 711e provided in the insertion portion 711a of the male joint portion 711 hits the retaining protrusion 713, and the first male joint portion 711 (relay member 73) is prevented from coming out of the first female joint 712.

  The elastic member 730 for preventing the above-described retaining protrusion 713 and the relay member 73 from tilting due to its own weight is such that the relay member 73 includes the first male side joint part 711 and the second male side joint part 721. The relay member 73 is not limited to that shown in FIGS. 7, 12B, and 12C.

  Next, a modified example will be described.

[Modification 1]
FIG. 15 is a schematic configuration diagram of an image forming apparatus according to the first modification.
In the image forming apparatus of Modification 1, the drum shaft is fixed to the main body side, and the process cartridge is positioned by inserting the drum shaft into the drum shaft hole provided at the center of the flange of the photosensitive member. is there.
In the image forming apparatus according to the first modification, a drum shaft hole 2d is formed in the back flange 2b of the photosensitive member 2, and a concave gear 111 having a conical pitch surface around the drum shaft hole 2d is formed on the outer surface of the flange 2b. Is provided. The front flange 2c is provided with a drum shaft hole 2e. The photoreceptor 2 is held by the face plates 11 and 18 without being positioned.

  A drum shaft 2a is rotatably supported on the main body side plate 91 via a bearing 90. The drum shaft 2a is linear with the motor shaft 81a of the photosensitive member driving motor 81 by a photosensitive member connecting means 93 such as a coupling. It is connected to. A first pulley 86, a convex gear 110 having a conical pitch surface, and a bearing 15 are fixed to the drum shaft 2a.

When the process cartridge 1 is mounted, as shown in FIG. 15, the drum shaft 2 a passes through the photosensitive member 2, and the concave gear 111 and the convex gear 110 are fitted to position the photosensitive member 2. Thereby, the distance between the central axis of the photoreceptor 2 and the central axis of the developing roller 5g is correctly regulated. At the same time, the fitting frame 11a, which is the positioned portion of the face plate 11, is fitted with the bearing 15 which is the positioning portion on the drum shaft 2a, and the process cartridge 1 is positioned.
Also in the configuration of the first modification, the process cartridge 1 is positioned with respect to the printer body with reference to the drum shaft 2a of the photosensitive member 2, so that the shaft center of the drive shaft 82 and the shaft center of the developing roller shaft 5j are shifted. However, since two sets of constant velocity joints are used as connecting means for connecting the drive shaft 82 and the developing roller shaft 5j, the first constant velocity joint can be used even if the drive shaft 82 and the developing roller shaft 5j are misaligned. The member 71 on the drive shaft side (first female joint 712 in FIG. 13) and the member on the developing roller shaft side of the second constant velocity joint 72 (second female joint 722 in FIG. 13) are integrated. By tilting the relay member 73, the drive shaft 82 and the developing roller shaft 5j can be connected. By tilting the relay member, a deviation angle α is generated between the relay member and the drive shaft and between the relay member and the developing roller shaft. However, the constant velocity joint can transmit the rotation on the driving side to the driven side at a constant speed even if a declination occurs between the male side joint and the female side joint. Even if a declination occurs between the female joint and the male joint of the constant velocity joint, the rotation of the drive shaft can be transmitted to the developing roller shaft at a constant velocity. As a result, the developing roller can be rotated at a constant speed, and abnormal images such as density unevenness can be suppressed.

  Further, a connecting device comprising two sets of constant velocity joints may be used as the connecting means 93 for connecting the drum shaft 2a and the motor shaft 81a of the photosensitive member driving motor 81 shown in FIG. Since the connection between the drum shaft 2a and the motor shaft 81a is not released until the motor breaks down, it is frequently used as a connection means for connecting the developing roller shaft 5j extracted from the apparatus main body together with the process cartridge and the drive shaft 82. There is no engagement and separation. Therefore, when the connecting device 93 of the present invention is provided in the connecting means 93 for connecting the drum shaft 2a and the motor shaft 81a of the photosensitive member driving motor 81 shown in FIG. 15, the first female joint as shown in FIG. A retaining protrusion 713 may be formed at each open end of the 712 part and the second female side joint part 722.

  In FIG. 16, when the first male second joint 721 and the motor shaft 81 are connected in a state where the first and second male joints 711 and 721 are engaged with the female joint, respectively. As shown in FIG. 14A, the second male joint 721 is simply provided by providing an elastic member between the insertion portion of the first male joint and the inner peripheral surface of the outer ring portion of the first female joint. Is greatly inclined by its own weight, and the connection between the second male joint 721 and the motor shaft 81 cannot be performed well. Therefore, when connecting the 2nd male side joint 721 and the motor shaft 81 in the state which engaged the 1st, 2nd male side joint 711,721 with the female side joint, respectively, it is 1st male. A ring-shaped portion between the insertion portion of the side joint 711 and the inner peripheral surface of the outer ring portion of the first female side joint 712 and between the insertion portion of the second male side joint 721 and the inner peripheral surface of the outer ring portion of the second female side joint 722. Insert the elastic member. Thereby, it can suppress that the relay member 73 and the 2nd male side joint 721 incline largely with dead weight, and can maintain the connection means 93 in a substantially horizontal attitude | position. Thereby, after engaging the first and second male side joints 711 and 721 with the female side joint, the connection between the second male side joint 721 and the motor shaft 81 can be performed.

  In the above description, the apparatus using the developing roller shaft of the developing roller of the developing unit that is the driven unit of the process cartridge and the connecting means including two constant velocity joints for connecting the driving shaft has been described. For example, the charging roller shaft of the charging unit and the driving shaft on the apparatus main body side may be connected by the connecting means using the two sets of constant velocity joints described above. Further, the connection between the application roller shaft of the lubricant application roller and the drive shaft on the apparatus main body side may be performed by the connection means using the two sets of constant velocity joints described above. Further, the connection between the transport auger shaft of the cleaning device and the drive shaft on the apparatus main body side may be performed by the connecting means using the two sets of constant velocity joints described above. Further, the present invention can be applied not only to the process cartridge but also to the fixing unit.

FIG. 17 is a schematic configuration diagram of the fixing unit 60.
Since the configuration inside the case of the fixing unit 60 shown in FIG. 17 has been described above, only the main part will be described here.
A roller gear 66d is fixed to the shaft 66a of the driving roller 66 disposed inside the case 60a, and a driven gear fixed to the driven shaft 60b rotatably supported on the side surface of the case 60a is fixed to the roller gear 66d. 60c is engaged. The first female joint 712 or the first male joint 711 of the first constant velocity joint 71 is concentrically fixed to the tip of the driven shaft 60b. One end of the shaft 66a of the driving roller 66 is rotatably supported by a face plate 195a that is detachably attached to the front side plate 195 of the printer main body, and the other end is rotatable in the hole 196a of the back side plate 196. It is supported via a bearing 66b.

The driving device 160 is fixed to the back side plate 196 of the image forming apparatus main body, and includes a holding plate 161, a driving motor 162 as a driving source, a transmission mechanism portion 163, and a driving shaft 164. The drive motor 162 is fixed to the holding plate 161. The transmission mechanism 163 includes a transmission gear 163a, a driving pulley 163c, a driven pulley 163d, and a timing belt 163e. The transmission gear 163 a is fixed to a rotating shaft 163 b that is rotatably supported by the holding plate 161 and the back side plate 196, and meshes with an output gear 162 a that extends from the drive motor 162. A driving pulley 163c is fixed to the rotating shaft 163b, and the timing belt 163e is stretched between the driving pulley 163c and the driven pulley 163d. The driven pulley 163d is fixed to a drive shaft 164 that is rotatably supported by the holding plate 161 and the back side plate 196. The rotation of the drive motor 162 is transmitted to the drive shaft 164 via the output gear 162a, the transmission gear 163a, the rotation shaft 163b, the drive pulley 163c, the timing belt 163e, and the driven pulley 163d.
Further, the second female joint 722 or the second male joint 721 of the second constant velocity joint 72 is concentrically fixed to the fixing roller side end of the drive shaft 164. The drive shaft 164 is rotatably held by the holding plate 161 via the bearing 87 and is rotatably fitted to the back side plate 196 via the bearing 84.

  As shown in FIG. 17, when the fixing unit 60 is attached to the apparatus main body, the bearing 66 b fixed to the shaft 66 a of the driving roller 66 is fitted into the hole 196 a of the back side plate 196, so that the fixing unit 60 is attached to the apparatus main body. Is positioned with respect to. At this time, even if the shaft center of the driven shaft 60b and the shaft center of the drive shaft 164 are shifted due to the accumulation of tolerances, the relay member of the connecting means is inclined and the drive shaft and the driven shaft are connected. In addition, since the drive shaft and the driven shaft are connected by the constant velocity joint, the drive roller can be rotated at a constant speed even if the drive shaft has a declination. Thereby, abnormal images such as uneven fixing can be suppressed.

  Further, the developing unit is detachable from the apparatus main body as a single unit, and in addition to connecting the developing roller shaft and the drive shaft of the apparatus main body, an image in which the conveying screw shaft is connected to the second drive shaft of the apparatus main body. The present invention can be applied to a forming apparatus. In this case, the developing roller shaft and the drive shaft of the apparatus main body are connected to position the developing unit with respect to the apparatus main body. As a result, an axial misalignment may occur between the transport screw shaft and the second drive shaft. Therefore, the connection means using the above-mentioned two sets of constant velocity joints is used for connection between the conveying screw shaft and the second drive shaft.

The present invention is not limited to an intermediate transfer tandem color image forming apparatus.
For example, as shown in FIG. 18, the present invention can also be applied to a direct transfer tandem color image forming apparatus. Further, as shown in FIG. 19, the present invention is also applied to a color image forming apparatus using a drum-shaped intermediate transfer body 141 in place of the intermediate transfer belt 41 in the electrophotographic color image forming apparatus of the intermediate transfer tandem method. be able to. Further, as shown in FIG. 20, one process cartridge 1 as described above is provided, an image is formed on the photosensitive member 2 of the process cartridge 1, and the image is transferred by a transfer roller 50 to form an image on a recording material. The present invention can also be applied to a direct transfer type monochrome image forming apparatus for recording.

As described above, the connecting means 70 as the connecting device of the present embodiment is driven to rotate by receiving the driving force from the developing roller shaft as a driven shaft for transmitting the driving force to the developing roller as the rotating body and the developing driving motor as the driving source. It connects with the drive shaft to do. The connecting means has an annular space having one end opened, and a track groove (inner groove) extending in an axial direction on at least one of an inner peripheral surface of the outer ring portion that is an outer wall surface of the annular space and an outer peripheral surface of the inner ring portion that is an inner wall surface Or a female side joint that is a ball non-retaining member formed with a plurality of outer grooves) at equal intervals in the circumferential direction, and a part of the female side joint is incorporated in the annular space of the female side joint, along the track groove formed in the ball non-retaining member Two constant velocity joints having a male side joint that is a ball holding member that holds the ball that slides are arranged in series in the axial direction. Also, a female joint that protrudes from the inner ring of the annular space of the female joint of at least one constant velocity joint and / or the open end of the outer ring of the inner ring and prevents the male joint from coming out of the female joint. And an integral retaining protrusion. Further, the opening end of the female side joint is configured to be elastically deformable.
As described above, since the retaining protrusion is an integral part of the female joint, the number of parts can be reduced by the retaining ring, and the cost of the apparatus and the part management cost can be reduced.
In addition, since the opening end of the female joint can be elastically deformed, it can be assembled simply by pressing the male joint strongly into the female joint even if the female joint has a retaining protrusion. Therefore, after inserting the male side joint into the female side joint, it is possible to reduce the number of assembling steps and simplify the assembling work compared to fitting a retaining ring near the open end of the annular space of the female side joint. it can.

  Also, an annular space between the male side joint of at least one constant velocity joint and the inner peripheral surface of the outer ring portion of the female side joint and / or an annular shape between the male side joint and the outer peripheral surface of the inner ring portion of the female side joint. A ring-shaped elastic member is inserted into the space. By comprising in this way, when a male side joint and a female side joint are engaged, it suppresses by the elastic force of an elastic member that the member (relay member) which is not connected to the axis | shaft inclines with own weight. Can do. As a result, if the member of the constant velocity joint connected to the other shaft is moved in the axial direction, it can be engaged with the member (relay member) that is not connected to the shaft of the constant velocity joint. The shaft and the developing roller shaft can be connected.

  Further, the hardness of the elastic member is made lower than the hardness of the material forming the female joint. With this configuration, when the process cartridge is inserted into the apparatus main body and the insertion portion of the male side joint is inserted into the female side joint, the shaft between the drive shaft and the developing roller shaft is inserted between the shaft center. Even if there is a deviation, the relay member can be easily inclined and the insertion part of the male side joint can be inserted into the annular space of the female side joint. As a result, the process cartridge can be smoothly mounted on the apparatus main body.

  When the constant velocity joint on the developing roller shaft side is the first constant velocity joint and the constant velocity joint on the drive shaft side is the second constant velocity joint, the first constant velocity joint, the drive shaft side member, The member on the developing roller shaft side of the high-speed joint is an integrated object (relay member). Thus, by integrating the first constant velocity joint, the drive shaft side member, and the member on the developing roller shaft side of the second constant velocity joint, the number of parts can be reduced, and the connecting means 70 can be reduced. A simple configuration can be achieved.

A developing roller having a developing roller as a rotating body and a developing roller shaft for transmitting a driving force to the developing roller, and positioning a process cartridge as a unit detachable from the apparatus main body with respect to the apparatus main body, and then developing roller shaft In the connection method that connects the drive and the driving time zone,
By using the above-mentioned connecting means for connecting the developing roller shaft and the driving shaft, even if there is a misalignment between the driving shaft and the developing roller shaft, the relay member is inclined, and the driving shaft and the developing roller shaft Can be connected. Further, even if there is a misalignment between the drive shaft and the developing roller shaft, the developing roller shaft can be rotated at a constant speed.

  Further, in the image forming apparatus, by using the above-described connecting means as the connecting means for connecting the developing roller shaft and the drive shaft of the process cartridge, a good image without density unevenness can be obtained.

1 is a schematic configuration diagram illustrating a printer according to an embodiment. FIG. 3 is an enlarged configuration diagram showing a process cartridge. (A) is a front view when the process cartridge is viewed from the back side of the apparatus main body. (B) is a perspective view when the process cartridge is viewed from the back side of the apparatus main body. FIG. 2 is a schematic configuration diagram when a process cartridge is mounted on an apparatus main body. FIG. 2 is a schematic configuration diagram before a process cartridge is mounted on a printer body. FIG. 3 is a main part schematic perspective view showing a drive transmission unit of the developing unit. The schematic block diagram of a connection means. The transverse cross section of the 1st female side joint. The figure which looked at the 1st female side joint from the axial direction. The cross-sectional view of a 1st male side joint. FIG. 3 is a schematic configuration diagram of a connecting unit when the developing roller shaft and the drive shaft are connected in a state where the axis of the developing roller shaft and the axis of the driving shaft are displaced. (A) is a schematic block diagram of the connection means which used the 1st male side joint and the 2nd male side joint as a relay member. (B) is a schematic block diagram of the connection means which used the 1st male side joint and the female side joint as a relay member. (C) is a schematic block diagram of the connection means which used the 1st female side joint and the 2nd male side joint as a relay member. The schematic block diagram of the connection means which connected the 1st constant velocity joint and the 2nd constant velocity joint with the connection shaft. (A) is a schematic block diagram of the connection means of the structure which inserted the elastic member between the outer peripheral surface of the insertion part of a 1st male side joint, and the inner peripheral surface of the outer ring part of a 1st female side joint. (B) is a figure explaining the subject in the connection means of the structure which has not inserted the elastic member between the outer peripheral surface of the insertion part of a 1st male side joint, and the inner peripheral surface of the outer ring part of a 1st female side joint. FIG. 9 is a main part configuration diagram of an image forming apparatus according to a first modification. FIG. 11 is a main part configuration diagram showing a configuration of a connecting means for connecting a motor shaft and a drum shaft of a photosensitive member drive motor in an image forming apparatus according to Modification 1; FIG. 2 is a diagram illustrating a schematic configuration of an image forming apparatus in the vicinity of a fixing unit. The figure which shows the tandem type color image forming apparatus of a direct transfer system. 1 is a diagram illustrating an intermediate transfer type tandem color image forming apparatus using an intermediate transfer drum. FIG. The figure which shows a monochrome image forming apparatus.

Explanation of symbols

1Y, C, M, K: each process cartridge 2Y, C, M, K: photoconductor 4: charging unit 5: developing unit 6: lubricant application unit 11: back side plate 13: secondary reference hole 14: secondary reference pin 18: Front side plate 20: Optical writing unit 60: Fixing unit 70: Connection means 71: First constant velocity joint 72: Second constant velocity joint 73: Relay member 75: Connection shaft 80: Drive device 81: Photoconductor drive Motor 82: Drive shaft 83: Second pulley 85: Timing belt 86: First pulley 88: Auxiliary support member 89: Holding plate 91: Main body side plate 94: Development drive motor 97: Electromagnetic clutch 140: First gear 142: Idler gear 143 : Second gear 173: ball 174: retaining ring 190: drive transmission mechanism 711: first male side joint 712: first female side joint 713: retaining Projection 721: second male joint 722: second female joint 730: elastic member

Claims (6)

In a coupling device that couples a driven shaft for transmitting a driving force to a rotating body and a driving shaft that receives a driving force from a driving source and rotates.
A ball non-holding member having an annular space with one end opened, and a plurality of track grooves extending in the axial direction at equal intervals in the circumferential direction on at least one of an outer wall surface and an inner wall surface of the annular space, and a part of the ball Two constant velocity joints having a ball holding member which is incorporated in the annular space of the non-holding member and holds the ball sliding along the track groove formed in the ball non-holding member are arranged in series in the axial direction. Place and
At least one constant velocity joint is provided with a retaining protrusion that protrudes from the open end of the outer wall surface and / or inner wall surface of the annular space of the ball non-holding member and prevents the ball holding member from coming off the ball non-holding member. The connecting device is characterized in that the retaining protrusion and the ball non-holding member are integrally formed of the same material, and the opening end of the non-ball holding portion is elastically deformable. The connecting device according to claim 1.
Ring in the annular space between the ball holding member of at least one constant velocity joint and the outer wall surface of the ball non-holding member and / or in the annular space between the ball holding member and the inner wall surface of the ball non-holding member A connecting device characterized by inserting a cylindrical elastic member. The connecting device according to claim 2.
A coupling device, wherein the hardness of the elastic member is lower than the hardness of the material forming the ball non-holding member. The connecting device according to any one of claims 1 to 3,
When the constant velocity joint on the driven shaft side is the first constant velocity joint and the constant velocity joint on the drive shaft side is the second constant velocity joint,
The connecting device characterized in that the driving shaft side member of the first constant velocity joint and the driven shaft side member of the second constant velocity joint are integrated. A rotating body and a driven shaft for transmitting a driving force to the rotating body, and after positioning a unit that can be attached to and detached from the apparatus main body with respect to the apparatus main body, the driven shaft and the apparatus main body In a coupling method for coupling with a drive shaft that receives a driving force from a driving source provided in the rotary drive,
The connection method characterized by performing the connection with the said driven shaft and a drive shaft using the connection apparatus in any one of Claims 1 thru | or 4. A unit having a rotating body and a driven shaft for transmitting a driving force to the rotating body, and detachable from the apparatus body;
An image forming apparatus comprising: a connecting unit that connects the driven shaft and a driving shaft that is rotated by receiving a driving force from a driving source provided in the apparatus main body in a state where the unit is positioned with respect to the apparatus main body. In the device
An image forming apparatus using the connecting device according to claim 1 as the connecting means.

Images