JP6954048B2 - Drive device and image forming device - Google Patents

Description

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

Conventionally, a drive source, a plurality of drive transmission members that transmit the driving force of the drive source to the drive member, a drive source holding member that holds the drive source, and a drive source holding member that sandwiches at least one drive transmission member. An intermediate that is arranged between an opposing member, a drive source holding member, and the facing member, is positioned at at least one of the driving source holding member and the facing member, and has one of a plurality of the driving transmission members. A drive device including a member is known.

Patent Document 1 sandwiches, as the drive device, a motor mounting plate as a drive source holding member for holding a motor as a drive source and a planetary gear mechanism composed of a plurality of drive transmission members such as a sun gear and an internal gear. Describes a machine having an output shaft end plate which is an opposing member facing the motor mounting plate and a cylindrical housing which is an intermediate member positioned at the motor mounting plate and the output shaft end plate and having an internal gear. .. The motor mounting plate has a cylindrical positioning protrusion whose outer diameter is substantially the same as the inner diameter of the housing. The housing is positioned on the motor mounting plate by fitting the positioning protrusion of the motor mounting plate to the motor mounting plate side end of the housing. Further, the output shaft end plate also has a cylindrical positioning convex portion whose outer diameter is substantially the same as the inner diameter of the housing, and this positioning convex portion fits into the output shaft end plate side end portion of the housing. The housing is positioned on the output shaft end plate. Then, by fastening the motor mounting plate to the fastening portion where the motor mounting plate provided on the outside of the housing of the output shaft end plate is fastened, the housing is narrowed between the motor mounting plate and the output shaft end plate. It is fixed in a shape like that. As a result, the motor mounting plate, the output shaft end plate, and the housing are fixed to each other. Further, a main body fastening portion for fastening to the main body device is provided outside the fastening portion to which the motor mounting plate of the output shaft end plate is fastened.

However, in the drive device described in Patent Document 1, there is a risk that the device will become large in size.

In order to solve the above problems, the present invention transmits the driving force of the driving source to the driving source and the driving member.
A plurality of drive transmission members and a drive source holding member for holding the drive source, and at least one drive
Opposing member facing the drive source holding member across the drive transmission member, and the drive source holding member and the front
At least one of the drive source holding member and the facing member, which is arranged between the facing member and the driving source holding member.
An intermediate member positioned on the member of the above and having one of the plurality of the drive transmission members is provided.
In the drive device, the positioning unit that positions the intermediate member and one of the members is tightened.
The connecting member penetrates, and the drive source holding member, the intermediate member, and the opposing member are fastened together to mount the main body.
The drive source holding member, the intermediate member, and the opposing member are attached to the book.
It is characterized in that it is fastened together with a member that holds a drive transmission member arranged in a body device.

According to the present invention, the drive device can be miniaturized.

The schematic block diagram which shows the printer which concerns on embodiment. Perspective view of the fixing device. The block diagram of the main part of the pressurizing adjustment mechanism provided in the fixing device. A cross-sectional view orthogonal to the axial direction of the back end of the fixing device. A cross-sectional view orthogonal to the transport direction of the sheet material at the back end of the fixing device. (A) is a diagram showing a state when the pressure roller is in a pressurized state, and (b) is a diagram showing a state when the pressure roller is in a depressurized state. An exploded perspective view of the drive unit of the pressurization adjustment mechanism. Cross-sectional view of the drive unit cut parallel to the axial direction. A front view of the drive unit from which the second housing has been removed, as viewed from the left side of FIG. The front view which further removed the worm wheel, the first housing, the drive shaft, the first output gear and the second output gear from the state of FIG. An exploded perspective view of the load applying portion. FIG. 8 is a cross-sectional view taken along the line AA of FIG. BB sectional view of FIG. The figure which shows the state when the pressure roller is changed from the depressurized state (no pressure) to the pressure state. It is a figure explaining the movement of each gear of a drive part when a cam member rotates faster than a rotation speed which receives a drive force from a drive motor by the urging force of a spring, and rotates. (A) is a diagram showing a state before the drive connecting member rotates faster than the rotational drive speed, and (b) shows a state in which the drive connecting member rotates faster than the rotational drive speed due to the back torque. The figure which shows. The figure which looked at the device body from the back side. The figure which looked at the back side plate from the inside of the device. An exploded perspective view of the bracket, the first housing, and the second housing as viewed from the second housing side. A view of the bracket, the first housing, the second housing, and the back side surface of the device body as viewed from the back side of the device. A perspective view of the first housing as viewed from the second housing side. FIG. 21 is a cross-sectional view taken along the line EE of FIG. The figure which shows the state which the drive part was fastened to the apparatus main body. FIG. 23 is a cross-sectional view taken along the line AA of FIG. BB sectional view of FIG. 23. FIG. 23 is a cross-sectional view taken along the line CC of FIG. FIG. 23 is a sectional view taken along line DD of FIG. A modified example of the bracket 52.

Hereinafter, as an image forming apparatus to which the present invention is applied, an electrophotographic printer (hereinafter, simply referred to as a printer) that forms an image by an electrophotographic method will be described.
FIG. 1 is a schematic configuration diagram showing a printer according to an embodiment.
The printer shown in FIG. 1 is a monochrome printer. A process cartridge 1 as a detachable unit is detachably attached to the apparatus main body 100. The process cartridge 1 visualizes a photoconductor 2 as an image carrier that carries an image on the surface, a charging roller 3 as a charging means for charging the surface of the photoconductor 2, and a latent image on the photoconductor 2. A developing device 4 as a developing means, a cleaning blade 5 as a cleaning means for cleaning the surface of the photoconductor 2, and the like are provided. Further, an LED head array 6 as an exposure means for exposing the surface is arranged around the photoconductor 2.

Further, the process cartridge 1 is provided with a removable toner cartridge 7 as a developer container. The toner cartridge 7 has a developer accommodating portion 8 in the container body 22 for accommodating toner, which is a developer to be replenished to the developing apparatus 4. Further, the toner cartridge 7 of the present embodiment also integrally has a developer recovery unit 9 that recovers the toner (waste toner) removed by the cleaning blade 5.

Further, the printer uses a transfer unit 10 for transferring an image to a sheet material as a transfer material, a paper feeding device 11 for supplying the sheet material, a fixing device 12 for fixing the image transferred to the sheet material, and a sheet material. It is provided with a paper ejection device 13 for discharging to the outside of the device.

The transfer unit 10 includes a transfer roller 14 as a transfer member rotatably supported by the transfer frame 30. The transfer roller 14 is in contact with the photoconductor 2 with the process cartridge 1 mounted on the apparatus main body 100, and a transfer nip is formed at the contact portion between the two. Further, the transfer roller 14 is connected to a power source so that a predetermined direct current voltage (DC) and / or alternating current voltage (AC) is applied.

The paper feed device 11 includes a paper feed cassette 15 containing the sheet material P and a paper feed roller 16 for feeding the sheet material P housed in the paper feed cassette 15. Further, on the downstream side of the paper feed roller 16 in the sheet material transport direction, a pair of resist rollers 17 as timing rollers for measuring the transport timing and transporting the sheet material to the secondary transfer nip are provided. Examples of the sheet material P include thick paper, postcards, envelopes, plain paper, thin paper, coated paper (coated paper, art paper, etc.), tracing paper, OHP sheets, OHP films, and the like.

The fixing device 12 includes a fixing roller 18 and a pressure roller 19. The fixing roller 18 is heated by an infrared heater 23 installed inside the fixing roller. The pressure roller 19 is pressurized toward the fixing roller 18 and comes into contact with the fixing roller 18, and a fixing nip is formed at the contacting portion.

The paper ejection device 13 includes a pair of paper ejection rollers 20. The sheet material discharged to the outside of the device by the paper ejection roller 20 is loaded on the paper ejection tray 21 formed by denting the upper surface of the apparatus main body 100.

Subsequently, with reference to FIG. 1, the basic operation of the printer according to the present embodiment will be described. When the image-drawing operation is started, the photoconductor 2 of the process cartridge 1 is rotationally driven clockwise in FIG. 1, and the surface of the photoconductor 2 is uniformly charged to a predetermined polarity by the charging roller 3. Based on the image information input from an external device, the LED head array 6 irradiates the charged surface of the photoconductor 2 with light, and an electrostatic latent image is formed on the surface of the photoconductor 2.

By supplying toner to the electrostatic latent image formed on the photoconductor 2 in this way by the developing device 4, the electrostatic latent image is visualized (visualized) as a toner image.

Further, when the image-drawing operation is started, the transfer roller 14 is rotationally driven, and a predetermined direct current voltage (DC) and / or alternating current voltage (AC) is applied to the transfer roller 14 to cause the transfer roller 14 and the transfer roller 14. A transfer electric field is formed with the photoconductor 2.

At the lower part of the apparatus main body 100, the paper feed roller 16 starts rotational driving, and the sheet material P is fed out from the paper feed cassette 15. The delivered sheet material P is temporarily stopped from being conveyed by the resist roller 17.

After that, the rotation drive of the resist roller 17 is started at a predetermined timing, and the sheet material P is conveyed to the transfer nip at the timing when the toner image on the photoconductor reaches the transfer nip. Then, the toner image on the photoconductor 2 is collectively transferred onto the sheet material P as the transfer body by the transfer electric field. Further, the residual toner on the photoconductor that could not be completely transferred to the sheet material P is removed by the cleaning blade 5, and the removed toner is conveyed to the developer recovery unit 9 and recovered.

After that, the sheet material P to which the toner image is transferred is conveyed to the fixing device 12, and the toner image on the sheet material P is fixed to the sheet material P in the fixing device 12. Then, the sheet material P is discharged to the outside of the device by the pair of paper ejection rollers 20, and is stocked on the paper ejection tray 21.

Further, an opening / closing cover 37 that can be opened / closed in the direction of the arrow in the drawing is provided on the side surface (right side surface in the drawing) of the apparatus main body 100 on the paper feeding side. By opening the opening / closing cover 37, the process cartridge 1 which is a detachable unit is taken out from the apparatus main body 100 through the opened opening.

FIG. 2 is a perspective view of the fixing device 12, and FIG. 3 is a configuration diagram of a main part of the pressure adjusting mechanism 40 included in the fixing device 12. FIG. 4 is a cross-sectional view orthogonal to the axial direction of the back end portion of the fixing device 12, and FIG. 5 is a cross-sectional view orthogonal to the transport direction of the sheet material P at the back end portion of the fixing device 12.
The fixing device 12 is a moving member in which an infrared heater 23 is arranged inside, and a fixing roller 18 which is a member to be heated heated by the infrared heater 23 and a fixing roller 18 which is pressed against the fixing roller 18 to form a fixing nip as a nip portion. A pressurizing roller 19 and a pressurizing adjustment mechanism 40 for moving the pressurizing roller 19 with respect to the fixing roller 18 and adjusting the pressing force of the pressurizing roller 19 on the fixing roller 18 are provided.

The pressure adjusting mechanism 40 urges the pressure roller 19 toward the fixing roller 18 via a pair of lever members 41 that adjustably support the pressing force of the pressure roller 19 on the fixing roller 18, and the lever member 41. A pair of cam members 44 that move the pressure roller 19 in a direction away from the fixing roller 18 against the urging force of the spring 43 via a pair of springs 43 and a lever member 41 as urging means, and the cam member 44. It has a drive unit 50 and the like which are drive means for driving.

Both sides of the fixing roller 18 in the axial direction are rotatably supported by a pair of side plates 47. Both sides of the pressure roller 19 in the axial direction are rotatably supported by the lever member 41 of the pressure adjustment mechanism 40, respectively. As shown in FIG. 3, each lever member 41 is provided with a support shaft 41a at one end, and is rotatably supported by a side plate 47. A spring receiver 41b is provided at the other end of each lever member 41, one end of the spring 43 is attached to the spring receiver 41b, and the other end of the spring 43 is a side plate 47 as shown in FIG. It is attached to the spring receiver 47a provided in the above. A cam receiver 42 is formed on the other end side of the lever member 41, and the cam member 44 is in contact with the cam receiver 42.

The pair of cam members 44 are attached to the cam shaft 44a by parallel pins 44c (see FIG. 5) so as to rotate integrally with the cam shaft 44a. At the rear end of the camshaft 44a (the right end in FIG. 2), a cam gear 55 that meshes with the second output gear 54 of the drive unit 50 is camped by a parallel pin 55a so as to rotate integrally with the camshaft 44a. It is attached to the shaft 44a.

Further, the cam gear 55 is formed with a filler 45a of a rotation angle detection mechanism 45 that detects the rotation angle of the cam member 44. Further, an optical sensor 45b for detecting the filler 45a of the rotation angle detection mechanism 45 is attached to the side plate 47 on the back side. The filler 45a has a semicircular shape, and the optical sensor 45b is a photointerruptor (transmissive optical sensor).

FIG. 6A is a diagram showing a state when the pressure roller 19 is in a pressurized state, and FIG. 6B is a diagram showing a state when the pressure roller 19 is in a depressurized state. The left side of the drawings of FIGS. 6 (a) and 6 (b) shows the state of the rotation angle detection mechanism 45 in the pressurized state and the state in the depressurized state.
As shown in FIG. 6, the lever member 41 is in contact with the bearing 46 that receives the shaft 19a of the pressure roller 19. The bearing 46 is held by the side plate 47 so as to be reciprocally movable in the direction of arrow K in the drawing. Further, the filler 45a of the rotation angle detection mechanism 45 has a semicircular shape, and has an opening 45c on one end side in the rotation direction.

As shown in FIG. 6A, in the pressurized state, the filler 45a enters between the light emitting element and the light receiving element of the optical sensor 45b and blocks the optical path between them. Further, in the pressurized state, the bottom dead center of the cam member 44 is in contact with the cam receiver 42.

When the drive unit 50 is driven in order to shift from the pressurized state to the depressurized state, the cam member 44 and the filler 45a rotate counterclockwise in the drawing. Then, from the state shown in FIG. 6A, the cam member 44 pushes the cam receiver 42 toward the lower side in the drawing against the urging force of the spring 43. As a result, the lever member 41 rotates counterclockwise in the drawing with the support shaft 41a as a fulcrum, and the pressure roller 19 as a moving member is separated from the fixing roller 18 by the reaction force from the fixing roller 18. The pressure applied to the fixing roller 18 of the pressurizing roller 19 decreases.

Then, as shown in FIG. 6B, when the top dead center of the cam member 44 comes into contact with the cam receiver 42, the opening 45c is located between the light emitting element and the light receiving element of the optical sensor 45b, and the optics The light receiving element of the sensor 45b detects the light of the light emitting element. As a result, it is possible to detect that the pressurizing roller 19 has retracted to the depressurized position.

In the present embodiment, when a paper jam occurs in the fixing device 12, the pressure adjusting mechanism 40 depressurizes the paper. This makes it easier to remove the paper stuck in the fixing nip.

Further, when the printer shifts from the standby state to the sleep mode or when the power is turned off, the pressurizing adjustment mechanism 40 reduces the pressing force of the pressurizing roller 19 on the fixing roller 18, so that creep occurs in the nip portion. Can be prevented. Further, even when passing thick paper such as an envelope, the pressure adjusting mechanism 40 reduces the pressing force of the pressure roller 19 on the fixing roller 18, so that the fixing process can be performed without causing wrinkles. can.

When shifting from the depressurized state to the pressurized state, the drive motor 51 is driven in the direction opposite to the rotation direction when shifting from the pressurized state to the depressurized state. Then, the cam member 44 rotates clockwise in the drawing, the lever member 41 rotates clockwise with the support shaft 41a as a fulcrum by the urging force of the spring 43, and the pressure roller 19 presses the fixing roller 18. Pressurize. Further, when the filler 45a enters between the light receiving element and the light emitting element of the optical sensor 45b and a predetermined time elapses without the light receiving element detecting light, it is determined that the specified pressing force has been reached, and the drive motor 51 is determined. Stop driving.

FIG. 7 is an exploded perspective view of the drive unit 50 of the pressure adjusting mechanism 40, and FIG. 8 is a cross-sectional view of the drive unit 50 cut in parallel with the axial direction. Further, FIG. 9 is a front view of the drive unit 50 from which the second housing 56 has been removed as viewed from the left side of FIG. 8, and FIG. 10 shows the worm wheel 75 and the first housing 66 from the state of FIG. , The front view of the drive shaft 73, the first output gear 53, and the second output gear 54 removed.
The drive unit 50 of the present embodiment is mainly composed of a drive motor 51, a worm gear 60, a planetary gear mechanism 70, and a load applying unit 80, and the driving force is applied in the order of the worm gear 60, the load applying unit 80, and the planetary gear mechanism 70. Be transmitted.

As the drive motor 51, a brush motor that is cheaper and smaller than a brushless motor is used. The drive motor 51 is held by a bracket 52 which is a motor holding member. Specifically, the bracket 52 has a motor holding surface 155 parallel to the rotation axis direction of the planetary gear mechanism 70. The motor holding surface 155 has a notch 155a through which the shaft of the drive motor 51 penetrates. Further, the motor holding surface 155 is provided with two screw through holes 155b through which a screw for screwing the drive motor 51 passes, sandwiching the notch 155a. Two screw holes 51a are formed on the surface of the drive motor 51 facing the motor holding surface 155 with the motor shaft interposed therebetween. The drive motor 51 is held by the bracket 52 by screwing the screw through the screw through hole of the motor holding surface 155 into the screw hole 51a of the drive motor 51.

A worm 61 of the worm gear 60 is attached to the motor shaft of the drive motor 51 so as to rotate integrally with the motor shaft. A worm wheel 75 meshes with the worm 61. The worm wheel 75 is supported by a drive shaft 73 rotatably supported by a bracket 52 via a bearing 154.

11 is an exploded perspective view of the load applying portion 80, FIG. 12 is a sectional view taken along the line AA of FIG. 8, and FIG. 13 is a sectional view taken along the line BB of FIG.
The load applying portion 80 is mainly composed of a drive side coupling 75a, a driven side coupling 71b, a drive shaft 73, and a torque limiter 72 as a load applying means. The drive side coupling 75a is provided on the worm wheel 75. Drive-side engaging projections 175 are provided on the inner peripheral surface of the drive-side coupling 75a at intervals of 180 °. The worm wheel 75 is attached to the drive shaft 73 so as to rotate integrally. Specifically, the drive shaft 73 has a press-fitting portion 73a having a substantially D-cut cross section, and the worm wheel 75 is made of a material that is elastically deformable to some extent, such as resin, and has a cross section that is press-fitted into the press-fitting portion 73a. It has a press-fit hole 75c having a substantially D-cut shape. By press-fitting the press-fitting hole 75c into the press-fitting portion 73a of the drive shaft 73 while elastically deforming (increasing the diameter), the worm wheel 75 is attached to the drive shaft 73 so as to rotate integrally with the drive shaft 73. ..

One end of the drive shaft 73 is rotatably supported by the bracket 52 via a bearing 154. The other end of the drive shaft 73 has a support portion 73b rotatably supported by the second housing 56. The support portion 73b has a shorter diameter than the press-fit portion 73a.

A torque limiter 72 as a load applying means and a drive connecting member 71 are attached to the drive shaft 73. At the end of the torque limiter 72 on the worm wheel 75 side, two notches 72a extending in the axial direction are provided at intervals of 180 ° in the rotational direction. A parallel pin 74 is fitted in the drive shaft 73, and the parallel pin 74 is inserted into the notch 72a of the torque limiter 72.

Further, two engaging protrusions 72b extending in the axial direction are provided at the end of the torque limiter 72 on the drive connecting member side with an interval of 180 ° in the rotational direction. These engaging protrusions 72b are inserted into the engaging holes 71c provided on the facing surface of the drive connecting member 71 facing the torque limiter 72.

The drive connecting member 71 is rotatably supported by the drive shaft 73, and has a driven side coupling 71b and a gear portion 71a. The driven-side coupling 71b has an outer diameter that allows it to enter the drive-side coupling, and two driven-side engaging protrusions 171 are provided on the outer peripheral surface thereof at intervals of 180 ° in the rotational direction. There is.

As shown in FIGS. 7 and 8, the planetary drive transmission member 62 is rotatably supported by a first support shaft 152 that is caulked and fixed to the bracket 52. The planetary drive transmission member 62 is formed with the sun gear 62b of the planetary gear mechanism 70.

The planetary gear mechanism 70 includes the above-mentioned sun gear 62b, three planet gears 65 that mesh with the sun gear 62b, a carrier 64 that rotatably supports the planet gears 65, and an internal gear 66a that meshes with the planet gears 65. doing. The planetary gear mechanism 70 also includes a carrier holder 63 that holds the planetary gear 65 on the carrier 64.

The planetary gears 65 are rotatably supported by planetary support portions 64c provided on the carrier 64 at equal intervals in the rotation direction (see FIGS. 8 and 10). The carrier holder 63 is provided with a snap-fit portion 63a for attaching to the carrier 64. The carrier holder 63 is attached to the carrier 64 by passing the claw portion at the tip of the snap fit portion through the engaging hole portion 64b of the carrier 64 while elastically deforming the snap fit portion 63a. As a result, the planetary gear 65 is held by the carrier 64.

The internal gear 66a is provided in the first housing 66. The first housing 66 covers the worm gear 60, the planetary gear mechanism 70, and the load applying portion 80 by being combined with the bracket 52 and the second housing 56.

As shown in FIGS. 7, 8 and 10, the carrier 64 has a tubular supported portion 64a for being supported by the first support shaft 152, and the supported portion 64a is first supported. The carrier 64 is rotatably supported by the first support shaft 152 by being fitted into the shaft 152. Further, on the outer peripheral surface of the supported portion 64a, three drive connecting convex portions 164 that are drive-connected to the first output gear 53 rotatably supported by the first support shaft 152 are formed at intervals of 120 °. It is provided. On the other hand, the surface of the first output gear 53 facing the carrier 64 has a tubular portion into which the supported portion 64a is inserted, and the inner peripheral surface of the tubular portion has the drive connecting convex portion. Three grooves into which the 164 is fitted are provided with an interval of 120 °. As a result, the driving force is transmitted from the carrier 64 to the first output gear 53.

A second output gear 54 meshes with the first output gear 53, and the second output gear 54 is rotatably supported by a second support shaft 153 fixed to the bracket 52 by caulking. The second output gear 54 meshes with the cam gear 55 (see FIG. 2).

When the drive motor 51 is rotationally driven, it is decelerated by the worm gear 60, and the drive side coupling 75a and the drive shaft 73 are rotationally driven. When the drive-side engagement projection 175 of the drive-side coupling 75a is not in contact with the driven-side engagement projection 171, the drive torque of the drive motor 51 is applied to the torque limiter 72 via the drive shaft 73. When the drive torque is applied to the torque limiter 72, the torque limiter 72 operates, the transmission of the driving force from the torque limiter 72 to the drive connecting member 71 is cut off, and the drive connecting member 71 does not rotate.

When the drive-side engagement projection 175 of the drive-side coupling 75a comes into contact with the driven-side engagement projection 171, a driving force is transmitted from the drive-side coupling 75a to the driven-side coupling 71b, and the drive coupling member 71 is rotationally driven. do. Then, the driving force is transmitted from the gear portion 71a of the drive connecting member 71 to the input gear 62a of the planetary drive transmission member 62, and the sun gear 62b of the planetary gear mechanism 70 is rotationally driven.

When the sun gear 62b is rotationally driven, the planetary gear 65 that meshes with the sun gear 62b revolves around the sun gear 62b while rotating. As the planetary gear 65 revolves around the sun gear 62b, the carrier 64 rotates, and the first output gear 53 engaged with the carrier 64 rotates together with the carrier 64. Then, the driving force is transmitted to the second output gear 54 that meshes with the first output gear 53, and the cam member 44 is rotationally driven via the cam gear 55 (see FIG. 2).

As described above, when reducing the pressing force of the pressurizing roller 19 on the fixing roller 18, it is necessary to push the lever member 41 by the cam member 44 against the urging force of the spring 43, and the load on the cam member 44. The torque increases. Further, as a result of pushing the other end of the lever member 41 downward as shown in FIG. 3, the spring 43 is extended, the urging force of the spring 43 is increased, and the load torque of the cam member 44 is increased. Therefore, as the pressing force of the pressurizing roller 19 on the fixing roller 18 is reduced, the load torque of the cam member 44 increases.

When the drive transmission mechanism that transmits the driving force of the drive motor 51 of the drive unit 50 to the cam member 44 is composed of a gear train that transmits the drive by meshing a plurality of external tooth gears, a sufficient reduction ratio cannot be obtained. Therefore, by using a motor having a large drive torque as the drive motor 51, the output torque output to the cam member 44 is made larger than the load torque. As a result, the lever member 41 can be rotated against the urging force of the spring 43. However, a motor having a large drive torque is large and expensive. As a result, there is a problem that the size of the device is increased and the cost of the device is increased.

Therefore, the drive unit 50 of the present embodiment is configured to obtain a high reduction ratio by using the worm gear 60 and the planetary gear mechanism 70. Since a high reduction ratio can be obtained in this way, the output torque to the cam member 44 can be made larger than the load torque of the cam member 44 even if a motor having a low drive torque of the drive motor 51 is used. .. As a result, even if an inexpensive and small brush motor having a low drive torque is used as the drive motor 51, the cam member 44 can be satisfactorily driven to rotate against the urging force of the spring 43, and the pressure roller 19 can be driven. The pressing force on the fixing roller 18 can be adjusted.

Further, by using the worm gear 60 and the planetary gear mechanism 70, a large reduction ratio can be obtained without using a large-diameter gear, and the size of the device can be increased as compared with the case where a large reduction ratio is obtained in the gear train. It can be suppressed.

Further, in the present embodiment, since a high reduction ratio can be obtained, the rotation angle of the cam member 44 with respect to the drive amount of the drive motor 51 can be reduced. As a result, the rotation angle of the cam member 44 can be finely adjusted, and the pressing force can be finely adjusted.

Further, in the planetary gear mechanism 70 of the present embodiment, the sun gear 62b is an input, the internal gear 66a is fixed, and the carrier 64 is an output. The largest reduction ratio can be obtained by using the sun gear 62b input, the internal gear 66a fixed, and the carrier 64 output.

Further, when the fixing device 12 is assembled to the device main body 100, the tooth tips of the cam gear 55 provided on the fixing device 12 may hit the tooth tips of the second output gear 54 provided on the device main body 100. In this way, when the tooth tip of the cam gear 55 collides with the tooth tip of the second output gear 54 provided in the apparatus main body 100, the second output gear 54 rotates to form the second output gear 54 and the cam gear 55. Need to mesh. As described above, the drive unit 50 of the present embodiment is configured to obtain a high reduction ratio. Therefore, in order to transmit a force from the output side to rotate the stopped drive motor 51, it is necessary to rotate the drive motor 51. Great power is needed. Therefore, it is necessary to configure the drive unit 50 so that the second output gear 54 rotates to some extent without rotating the stopped drive motor 51.

Therefore, in the present embodiment, as shown in FIG. 12, two driven side engaging protrusions 171 and a driving side engaging protrusion 175 are provided with an interval of 180 ° in the rotational direction, and the drive connecting member 71 is wormed. It can rotate approximately 180 ° with respect to the wheel 75. As a result, the drive transmission member (second) downstream of the worm wheel 75 in the drive transmission direction until the drive connection member 71 rotates approximately half a turn without rotating the worm wheel 75 to rotate the stopped drive motor 51. The output gear 54, the first output gear 53, and each member of the planetary gear mechanism 70) can be rotated. As a result, when the fixing device 12 is assembled to the device main body 100, when the tooth tip of the cam gear 55 hits the tooth tip of the second output gear 54, the second output without rotating the stopped drive motor 51. The gear 54 rotates so that the second output gear 54 and the cam gear 55 can mesh with each other. As a result, a large force is not required when assembling the fixing device 12, and the fixing device 12 can be easily assembled.

FIG. 14 is a diagram showing a state when the pressurizing roller 19 is shifted from the depressurized state (no pressing force) to the pressurized state.
When the pressure roller 19 is in the depressurized state, as shown in FIG. 6B above, the top dead center of the cam member 44 at which the distance from the center of the rotation axis of the cam member 44 to the outer peripheral surface is maximum is set. It is in contact with the cam receiver 42. From this state, when the cam member 44 is rotated in the direction of the arrow A in FIG. 14, the cam member 44 with respect to the line B connecting the contact point S1 between the cam receiver 42 and the cam surface 44b and the rotation center O1 of the cam member 44. The urging direction F of the spring 43 received from the cam receiver 42 shifts in the rotational direction. As a result, the urging force of the spring 43 acts on the cam member 44 in the rotational direction of the cam member 44, the cam member 44 is pushed in the rotational direction, and the cam member 44 receives a driving force from the drive motor 51 to rotate. It rotates faster than the speed.

FIG. 15 is a diagram illustrating the movement of each gear of the drive unit 50 when the cam member 44 rotates faster than the rotation speed at which the cam member 44 receives the drive force from the drive motor 51 and rotates by the urging force of the spring 43.
The engaging portion between the drive transmission members, such as the meshing portion of the gear of the drive portion 50, has a predetermined play such as backlash. Therefore, when the cam member 44 rotates faster than the rotation drive speed due to the urging force of the spring 43, the cam shaft 44a rotates together with the cam member 44 faster than the rotation drive speed. As a result, as shown by the arrow A2 in the figure, the cam gear 55 attached to the cam shaft 44a rotates faster than the rotation drive speed. When the cam gear 55 rotates faster by the amount of play (backlash) with the second output gear 54, the teeth of the cam gear 55 hit the teeth of the second output gear 54 and push the second output gear 54 in the rotational direction. Then, as shown by the arrow A3 in the drawing, the second output gear 54 rotates faster by the amount of play with the first output gear 53, and then the first output gear 53 is pushed in to move the first output gear 53 in the drawing. As shown by the arrow A4, the first output gear 53 is rotated faster than the rotation drive speed.

Then, in the same manner as described above, the urging force (hereinafter referred to as back torque) of the spring 43 is transmitted from the first output gear 53 to the planetary gear mechanism 70 and the drive connecting member 71, and the drive connecting member 71 is subjected to the rotational driving speed. Rotates faster than.

FIG. 16A is a diagram showing a state before the drive connecting member 71 rotates faster than the rotational drive speed, and FIG. 16B is a diagram showing the state before the drive connecting member 71 rotates faster than the rotational drive speed, and FIG. 16B shows the drive connecting member 71 faster than the rotational drive speed due to the back torque. It is a figure which shows the state of rotation.
As shown in FIG. 16A, when the drive connecting member 71 receives a driving force from the drive motor 51 and rotates at a rotational drive speed, the drive side engaging projection 175 is driven from the upstream side in the rotation direction. It abuts on the side engaging projection 171 and transmits the driving force to the driving connecting member 71. As a result, the worm wheel 75 and the drive connecting member 71 are integrally rotating.

As shown by arrow A6 in FIG. 16B, when the drive connecting member 71 rotates faster than the rotational drive speed due to the back torque, the driven side engaging projection 171 rotates away from the driving side engaging projection 175. Move in the direction.

In the present embodiment, as described above, in order to facilitate the assembly of the fixing device 12, there is a play of approximately 180 ° between the driven side engaging projection 171 and the driving side engaging projection 175 of the drive connecting member 71. .. Therefore, the drive connecting member 71 accelerates due to the back torque, the driven side engaging projection 171 moves in the rotational direction by approximately 180 °, and then vigorously collides with the driving side engaging projection 175 from the upstream side in the rotational direction to collide. Sound may be generated.

Therefore, in the present embodiment, a torque limiter 72 is provided as a load applying means to apply a load to the rotation of the drive connecting member 71 due to the back torque. Specifically, the back torque is transmitted to the drive connecting member 71, and when the drive connecting member 71 rotates faster than the rotational drive speed, the back torque is input to the torque limiter 72 via the drive connecting member 71. The torque at which the torque limiter 72 operates is set to be less than the above-mentioned back torque, and when the back torque is input to the torque limiter 72, the torque limiter 72 operates and between the drive connecting member 71 and the drive shaft 73. Drive transmission is cut off.

When the torque limiter 72 is activated to cut off the drive transmission, a predetermined rotational load is generated. For example, when the torque limiter 72 is a friction type, the torque limiter 72 is more than the static friction force between the first member attached to the drive shaft 73 of the torque limiter 72 and the second member attached to the drive connecting member 71. When the torque applied to the first member is large, the second member rotates relative to the first member, and the drive transmission is cut off. Therefore, when the second member rotates relative to the first member and the drive transmission is blocked, a predetermined frictional force is generated between the first member and the second member. , Load occurs. Further, when the torque limiter 72 is a magnetic type, when the second member rotates relative to the first member and the drive transmission is blocked, the torque limiter 72 is between the first member and the second member. Is generated by a predetermined magnetic force, and a load is generated. In this way, when the torque limiter 72 is activated and the drive transmission is cut off, a rotational load is generated. Therefore, when the back torque is transmitted to the drive connecting member 71 and rotates faster than the rotational drive speed and the torque limiter 72 operates, a load is generated on the torque limiter 72 and the rotation of the drive connecting member 71 is braked. As a result, the rotation of the drive connecting member 71 is sufficiently decelerated, and then the driven side engaging projection 171 collides with the driving side engaging projection 175, so that the generation of collision noise can be suppressed.

Further, when the cam member 44 is rotationally driven by the driving force of the drive motor 51, no torque is applied to the torque limiter 72 and the torque limiter 72 does not operate, and the cam member 44 is driven by the urging force of the spring 43. Only when rotating, the torque limiter 72 operates to apply a load. As a result, the load when the cam member 44 is rotationally driven by the driving force of the drive motor 51 can be reduced, and an inexpensive motor having a low output torque can be used.

Further, in the present embodiment, even if the rotation speed of the cam member 44 is not detected by using a detection sensor or the like, a load can be applied when the cam member 44 rotates quickly by the urging force of the spring 43. Further, the structure is simpler than that in which the friction resistance member is moved and pressed against the drive connecting member 71 to apply a load when the cam member 44 rotates faster than a specified speed. Can give a load. As a result, the load applying portion 80 can be formed with an inexpensive configuration, and the cost of the device can be reduced. Further, by incorporating the torque limiter 72 by the drive side coupling 75a and the driven side coupling 71b, it is possible to suppress the increase in size of the load applying portion 80.

Further, in the present embodiment, the drive motor 51 is arranged so that the rotation axis direction of the drive motor 51 is orthogonal to the rotation axis direction of the sun gear 62b of the planetary gear mechanism 70. As a result, it is possible to suppress an increase in size in the axial direction as compared with the case where the drive motor 51 is arranged so that the rotation axis direction of the drive motor 51 is parallel to the rotation axis direction of the sun gear 62b.

FIG. 17 is a view of the main body of the device as viewed from the back side, and FIG. 18 is a view of the back side plate 101 as viewed from the inside of the device.
As shown in FIGS. 17 and 18, the fixing device 12 which is a detachable unit is detachably provided with respect to the apparatus main body. The back side plate 101 is provided with a fixing guide 110 that guides the fixing device 12 and holds the fixing device 12 mounted on the device main body when the fixing device 12 is attached to and detached from the device main body. The fixing guide 110 is a resin material and has a guide groove 114 for guiding the fixing device 12 as shown in FIG. Further, the front side plate of the main body of the apparatus also has a fixing guide having a similar guide groove.

Guide protrusions 12a are formed on both side surfaces of the fixing device 12. The fixing device 12 is guided by the guide protrusions 12a being guided by the guide grooves 114 of the fixing guides provided on both side plates, and is mounted on the main body of the device. When the fixing device 12 is attached to the main body of the device, the fixing device 12 is held by the fixing guide. That is, in the present embodiment, the fixing guide holds the main body side drive transmission member such as the cam gear 55 via the fixing device 12.
Further, as shown in FIG. 17, the drive unit 50 is screwed to the fixing guide 110 and the back side plate 101.

Next, the assembly of the bracket 52, the first housing 66, and the second housing 56 will be described.
FIG. 19 is an exploded perspective view of the bracket 52, the first housing 66, and the second housing 56 as viewed from the second housing 56 side, and FIG. 20 shows the bracket 52, the first housing 66, and the second housing 56. , The back side surface of the device main body is a view seen from the back side of the device.
The bracket 52, which is a motor holding member, is made of sheet metal and has first to fourth outer co-fastening portions 158a to 158d. The first outer co-tightening portion 158a is formed with a first outer screw through hole 151a through which a first main body fixing screw 91a for fastening the drive portion 50 to the apparatus main body penetrates. Further, the second outer screw through hole 151b through which the second main body fixing screw 91b penetrates through the second outer co-tightening portion 158b, and the third main body fixing screw 91c penetrates through the third outer co-fastening portion 158c. The third outer screw through hole 151c and the fourth outer co-tightening portion 158d are formed with a fourth outer screw through hole 151d through which the fourth main body fixing screw 91d penetrates.

Further, the bracket 52 has two positioning protrusions 52a and 52b on which the first housing 66, which is an intermediate member, is positioned. Further, in the second support shaft 153 on which the second output gear 54 is rotatably supported, a screw hole for screwing a housing mounting screw 92 for fastening the second housing 56, which is an opposing member, to the bracket 52 is screwed. 153a is formed.

The second housing 56 is made of a resin material and has first to third inner co-tightening portions 157a to 157c. The first inner co-tightening portion 157a is formed with a first positioning screw through hole 156a for positioning the first housing 66 and through which the first main body fixing screw 91a penetrates, and the second inner co-tightening portion 157b. Is formed with a second positioning screw through hole 156b for positioning the first housing 66 and through which the second body fixing screw 91b penetrates. The inner diameter of the second positioning screw through hole 156b is substantially the same as the outer diameter of the second positioning convex portion 66b1 of the second housing 56, which will be described later, and is the main reference for positioning. Is a long hole that is long in the vertical direction and serves as a reference for positioning. Further, the third inner co-tightening portion 157c has an inner screw through hole 156c through which the fourth main body fixing screw 91d penetrates.

Further, the second housing 56 has a first main body positioning hole 56a1 which is a main body positioning portion into which the first main body positioning protrusion 102a provided on the back side plate 101 fits, and a second main body positioning protrusion provided on the back side plate 101. It has a second main body positioning hole 56a2 which is a main body positioning portion into which 102b fits. The inner diameter of the first main body positioning hole 56a1 is substantially the same as the outer diameter of the first main body positioning protrusion 102a, which is the main reference for positioning, and the second main body positioning hole 56a2 has an elongated hole shape extending in the horizontal direction. It is a secondary standard for positioning. Further, the second housing 56 also has a mounting screw through hole 56b through which the housing mounting screw 92 penetrates.

As shown in FIG. 20, the fixing guide 110 attached to the back side plate 101 is made of a resin material, and the first fastening boss 111 in which the first screw hole 111a to which the first main body fixing screw 91a is fastened is formed. And the second fastening boss 112 in which the second screw hole 112a to which the second main body fixing screw 91b is fastened and the third screw hole 113a in which the third main body fixing screw 91c is fastened are formed. It has three fastening bosses 113.

The back side plate 101 is made of sheet metal, and has two main body positioning protrusions 102a and 102b for positioning the second housing 56 and a fourth screw hole 103 to which the fourth main body fixing screw 91d is fastened.

21 is a perspective view of the first housing 66 as viewed from the second housing side, and FIG. 22 is a cross-sectional view taken along the line EE of FIG.
The first housing 66, which is an intermediate member, is made of a resin material and has an internal gear 66a in the center. Further, the first housing 66 has first to third intermediate joint tightening portions 166a to 166c. The first intermediate co-tightening portion 166a has a cylindrical first positioning convex portion 66b1 having a first intermediate screw through hole 161a extending to the second housing side (front side in the drawing) and through which the first main body fixing screw 91a penetrates. Is formed. Further, the second intermediate co-tightening portion 166b has a cylindrical second positioning convex having a second intermediate screw through hole 161b extending to the second housing side (front side in the drawing) and through which the first body fixing screw 91a penetrates. Part 66b1 is formed. Further, the third intermediate joint tightening portion 166c is formed with a third intermediate screw through hole 161c through which the third main body fixing screw 91c penetrates.

Further, the first housing 66 has a first positioning hole 66c1 (see FIG. 20) into which the positioning protrusion 52a of the bracket 52 fits, and a second positioning hole 66c2 into which the positioning protrusion 52b fits. The inner diameter of the first positioning hole 66c1 is substantially the same as the outer diameter of the positioning protrusion 52a, which is the main reference for positioning, and the matching second positioning hole 66c2 is an elongated hole extending in the horizontal direction for positioning. It has become a subordinate standard of. Further, the first housing 66 has a shaft through hole 66d through which the second support shaft 153 penetrates.

23 is a view showing a state in which the drive unit 50 is fastened to the apparatus main body, FIG. 24 is a cross-sectional view taken along the line AA of FIG. 23, and FIG. 25 is a cross-sectional view taken along the line BB of FIG. 26 is a cross-sectional view taken along the line CC of FIG. 23, and FIG. 27 is a cross-sectional view taken along the line DD of FIG. 23.
As shown in FIG. 25, the drive unit 50 is fastened to the device main body 100 in a state where the second housing 56 is fastened to the second support shaft 153 by the housing mounting screws 92.
In the present embodiment, the drive motor 51 is arranged so that the rotation axis direction of the drive motor 51 is orthogonal to the rotation axis direction of the sun gear 62b of the planetary gear mechanism 70, and the rotation axis direction of the drive motor 51 is shown in FIG. 23. As shown in, it is parallel to the back side plate 101. As a result, the gap between the back side plate 101 and the outer cover of the printer can be narrowed as compared with the case where the rotation axis direction of the drive motor 51 is orthogonal to the back side plate 101, and the size of the printer can be reduced. Can be done.

As shown in the enlarged view of B1 in FIG. 25, the tip of the second support shaft 153 has a small diameter, and the second housing 56 has a step on the second support shaft 153 and the head of the housing mounting screw 92. It is fastened in a sandwiched form. In this way, with the second housing 56 fastened to the bracket 52 via the second support shaft 153, the drive unit 50 is fastened to the device main body 100 to the second support shaft 153 and the first support shaft 152. The rotatably supported drive transmission members (second output gear 54, first output gear 53, etc.) come out of the second support shaft 153 and the first support shaft 152 when the drive unit 50 is assembled to the apparatus main body 100. Can be prevented. As a result, the drive unit 50 can be easily fastened to the device main body 100.

Further, by fastening the second housing 56 to the bracket 52 via the second support shaft 153, the positioning projection 52a of the bracket 52 fits into the positioning hole 66c1 of the first housing 66 as shown in the enlarged view of C3 of FIG. Then, as shown in the enlarged view of B2 in FIG. 25, the positioning protrusion 52b fits into the positioning hole 66c2, and the first housing 66 is positioned on the bracket 52. By positioning the first housing 66 on the bracket 52, the shaft center of the internal gear 66a provided in the first housing and a plurality of planetary gears 65 supported by the first support shaft 152 of the bracket 52 are supported. It can be aligned with the axis center of the carrier. As a result, the internal gear 66a and the plurality of planetary gears can be accurately meshed with each other.

Further, as shown in the C1 enlarged view and the C2 enlarged view of FIG. 26, the positioning convex portions 66b1, 66b2 of the first housing 66 fit into the positioning screw through holes 156a, 156b of the second housing 56, and the first housing 66 and the first housing 66 (Ii) The housing 56 is positioned. As a result, the bracket 52 is positioned on the second housing 56 via the first housing 66.

By positioning the bracket 52, the first housing 66, and the second housing 56 in this way, the outer screw through holes 151a, 151b, 151c, 151d of the bracket 52 and the intermediate screw through holes of the first housing 66 are respectively positioned. The 161a, 161b, 161c and the screw through holes 156a, 156b, 156c of the second housing 56 can be overlapped with each other. As a result, the drive unit 50 can be easily fastened to the device main body 100 with the screws 91a, 91b, 91c, 91d for fixing the main body.

The second housing 56 is fastened with the housing mounting screw 92 by a drive transmission member rotatably supported by the second support shaft 153 and the first support shaft 152 when the drive unit 50 is assembled to the device main body (the first). This is performed in order to prevent the one output gear 53, the second output gear 54, etc.) from coming off, and to maintain the state in which the bracket 52, the first housing 66, and the second housing 56 are positioned with each other. Therefore, it is not necessary to keep the second housing 56 completely immovable in the axial direction, and there may be some play in the axial direction. Therefore, the axial length of the small diameter portion formed at the tip of the second support shaft 153 may be rough, and the tip of the second support shaft 153 may slightly protrude from the mounting screw through hole 56b. Further, it is not necessary to provide a small diameter portion at the tip of the second support shaft 153. The second housing 56 can be fastened to the bracket 52 by the housing mounting screw 92 in a state where it can be slightly moved in the axial direction without providing a small diameter portion at the tip of the second support shaft 153. Further, since it is not necessary to form a small diameter portion at the tip of the second support shaft 153 by cutting or the like, the manufacturing cost can be reduced.

Further, in the present embodiment, the second housing 56 is fastened by the housing mounting screw 92, but the present invention is not limited to this, and the second housing 56 may be fastened to the bracket 52 by snap-fitting or the like.

In this way, the drive unit 50 in a state where the bracket 52, the first housing 66, and the second housing 56 are positioned and assembled with each other by the housing mounting screws 92 is fastened to the device main body 100. Specifically, first, the main body positioning holes 56a1 and 56a2 of the second housing 56 are fitted into the main body positioning protrusions 102a and 102b provided on the back side plate 101 to position the drive unit 50 with respect to the device main body (FIG. 24 A1 enlarged view, D1 enlarged view of FIG. 27). The bracket 52 that holds the second output gear 54 and the like is positioned in the second housing 56 via the first housing 66. Therefore, by positioning the drive unit 50 with the device main body through the main body positioning holes 56a1 and 56a2 of the second housing 56, the second output gear 54 can be positioned at the target position of the device main body. As a result, the second output gear 54 can be accurately meshed with the cam gear 55, which is a drive transmission member on the main body side.

Further, the second output gear 54 can be positioned at a target position of the apparatus main body by directly positioning the bracket 52 holding the second output gear 54 on the apparatus main body 100. However, if the bracket 52 is directly positioned on the apparatus main body 100 for the following reasons, there is a problem that the drive unit 50 becomes large. That is, the drive unit 50 of the present embodiment includes the planetary gear mechanism 70, and the internal gear 66a including the plurality of planetary gears and the sun gear is inevitably enlarged. As a result, the first housing 66 having the internal gear 66a also becomes large. Therefore, when the bracket 52 is configured to be directly positioned on the device main body, the positioning structure for positioning the bracket 52 and the device main body needs to be provided on the outside of the first housing 66, and the drive unit 50 becomes large. be.

On the other hand, as in the present embodiment, the bracket 52 and the first housing 66 are positioned, the first housing 66 and the second housing 56 are positioned, and the main body positioning holes 56a1 and 56a2 provided in the second housing 56 are used. By positioning the drive unit 50 on the main body of the device, it is possible to suppress the increase in size of the drive unit 50 and position the second output gear 54 at a target position of the main body of the device.

After the drive unit 50 is positioned on the device body in this way, the drive unit 50 is fastened to the device body 100 by the screws 91a to 91d for fixing the body. Specifically, the first main body fixing screw 91a is screwed into the first screw hole 111a of the first fastening boss 111. As a result, the first outer co-tightening portion 158a of the bracket 52, the first intermediate co-tightening portion 166a of the first housing 66, and the first inner co-tightening portion 157a of the second housing 56 are connected by the first body fixing screw 91a. It is fastened together with the fixing guide 110. Further, the second main body fixing screw 91b is screwed into the second screw hole 112a of the second fastening boss 112. As a result, the second outer co-tightening portion 158b of the bracket 52, the second intermediate co-tightening portion 166b of the first housing 66, and the second inner co-tightening portion 157b of the second housing 56 are connected by the second body fixing screw 91b. It is fastened together with the fixing guide 110. Further, the third main body fixing screw 91c is screwed into the third screw hole 113a of the third fastening boss 113. As a result, the third outer co-tightening portion 158c of the bracket 52 and the third intermediate co-tightening portion 166c of the first housing 66 are co-fastened to the fixing guide 110 by the first main body fixing screw 91a. Further, the fourth main body fixing screw 91d is screwed into the fourth screw hole 103 of the back side plate 101. As a result, the fourth outer co-tightening portion 158d of the bracket 52 and the third inner co-tightening portion 157c of the second housing 56 are co-fastened to the back side plate 101 by the fourth main body fixing screw 91d.

By fastening the bracket 52, the first housing 66, and the second housing 56 together in this way, the first housing 66 is fastened to the bracket 52, and the second housing 56 is fastened to the first housing 66. Compared to the conventional configuration in which any of the bracket 52, the first housing 66, and the second housing 56 is fastened to the apparatus main body, the size of the drive unit 50 is suppressed, the cost is reduced by reducing the number of parts, and the assembly man-hours are reduced. Manufacturing costs can be reduced. The reason will be described below.

As described above, the internal gear 66a of the planetary gear mechanism 70 has a large diameter. In the conventional configuration in which the first housing 66 is fastened to the bracket 52 and the second housing 56 is fastened to the first housing 66, the first housing 66 having the large-diameter internal gear 66a is fastened to the bracket 52. A fastening portion and a fastening portion to which the second housing 56 is fastened will be provided respectively. Further, the first housing 66 needs to be provided with a positioning portion for positioning the bracket 52 and a positioning portion for positioning the second housing 56. As a result, the large first housing 66 having the large-diameter internal gear 66a becomes larger, and the device becomes larger. Further, a screw for fastening the first housing 66 to the bracket 52, a screw for fastening the second housing 56 to the first housing 66, and a screw for fastening the drive unit 50 to the apparatus main body are required, and the number of parts is required. Will increase. Further, there are a step of fastening the first housing 66 to the bracket 52, a step of fastening the second housing 56 to the first housing 66, and a step of fastening the drive unit 50 to the apparatus main body, which requires a large number of assembly man-hours.

On the other hand, in the present embodiment, the three intermediate co-fastening portions 166a, 166b, 166c, the positioning portions (positioning holes 66c1, 66c2) to be positioned on the bracket 52, and the second housing 56 are positioned on the first housing 66. By providing the positioning portions (positioning convex portions 66b1, 66b2), the bracket 52, the first housing 66, and the second housing 56 can be positioned and fastened to each other. As a result, it is possible to suppress an increase in the size of the first housing 66 and an increase in the size of the drive unit 50 as compared with the conventional configuration described above.

Further, in the present embodiment, the bracket 52, the first housing 66 and the second housing 56 can be fastened with the four screws of the first to fourth main body fixing screws 91a to 91d, as compared with the conventional configuration. Therefore, the number of screws can be reduced. Further, by fastening the drive unit 50 to the device main body with four main body fixing screws 91a to 91d, the bracket 52, the first housing 66, and the second housing 56 can be fastened to each other. Assembling man-hours can be reduced compared to the configuration.

Further, as shown in FIG. 21 and the like, the first housing 66 is fastened on both sides with the internal gear 66a interposed therebetween. As a result, the first housing 66 is stably fastened without rattling, and the internal gear 66a can be satisfactorily meshed with the plurality of planetary gears 65.

Further, the fourth main body fixing screw 91d is fastened to the back side plate 101 made of metal and made of sheet metal. As a result, the drive motor 51 can be grounded via the bracket 52 made of sheet metal, the fourth main body fixing screw 91d, and the back side plate 101 made of sheet metal. As a result, it is possible to suppress an adverse effect on the operation of the drive motor 51.

Further, in the present embodiment, the first housing 66 has a shaft through hole 66d through which the second support shaft 153 penetrates, and as shown in FIG. 25, the first housing 66 is attached to the second support shaft 153. It faces the supported second output gear 54. As a result, the movement of the second output gear 54 toward the bracket side can be restricted by the first housing 66, and the second output gear 54 can be satisfactorily meshed with the cam gear 55.

Further, in the present embodiment, the positioning convex portions 66b1 and 66b2 in which the second housing 56 is positioned are formed into a cylindrical shape, and the positioning convex portions 66b1 and 66b2 are provided with screw through holes through which the main body fixing screws 91a and 91b pass. It is provided. As a result, the positioning protrusions 66b1 and 66b2 where the second housing 56 is positioned and the screw through holes through which the main body fixing screws 91a and 91b penetrate are smaller than those provided at different positions. It is possible to reduce the size of the drive unit 50.

Further, either one of the positioning portions of the first housing 66 and the bracket 52 may have a tubular shape having a screw through hole through which the main body fixing screws 91a and 91b pass, similarly to the positioning portion of the second housing. .. As a result, it is possible to further suppress the increase in diameter of the first housing 66, and further reduce the size of the drive unit 50.

Further, in the present embodiment, in positioning the first housing 66 and the second housing 56, a positioning screw is provided in the first housing 66 with a cylindrical positioning convex portion, and the positioning convex portion is fitted in the second housing 56. Although the through hole is provided, the second housing 56 may be provided with a cylindrical positioning convex portion, and the first housing 66 may be provided with a positioning screw through hole.

FIG. 28 is a modified example of the bracket 52.
In the modified example shown in FIG. 28, the fourth outer co-tightening portion 158d is provided below the center of the rotation axis of the drive motor 51. In this way, by providing the fourth outer co-tightening portion 158d below the center of the rotating shaft of the drive motor 51, the bracket 52 can be provided on both one side and the other side of the center of the rotating shaft of the drive motor 51. Is concluded at. For example, when the bracket 52 is fastened only on one side of the center of the rotation shaft of the drive motor 51, the other side of the bracket 52 has a form like a cantilever support, and the vibration of the drive motor 51 may cause the other side to vibrate. be.

On the other hand, as shown in FIG. 28, by fastening the bracket 52 on both one side and the other side of the center of the rotation axis of the drive motor 51, the bracket 52 is suppressed from vibrating due to the vibration of the drive motor 51. be able to.

Further, in the example shown in FIG. 28, the bracket 52 is fastened at four places, but the bracket 52 is fastened at two places on one side and one place on the other side of the center of the rotation axis of the drive motor 51. You may.

The above description is an example, and the effect peculiar to each of the following aspects is exhibited.
(Aspect 1)
Each of a plurality of drive transmission members (in this embodiment, the worm gear 60, the worm wheel 75, and the planetary gear mechanism 70) transmit the driving force of the drive source to a drive source such as the drive motor 51 and a drive member such as the cam member 44. A second housing facing a drive source holding member with at least one drive transmission member sandwiched between a gear, a first output gear 53 and a second output gear 54), a drive source holding member such as a bracket 52 for holding the drive source, and a drive transmission member. A second member such as 56, which is arranged between the drive source holding member and the facing member, is positioned at at least one of the drive source holding member and the facing member, and has one of the plurality of the drive transmission members. In a drive device such as a drive unit 50 provided with an intermediate member such as a housing 66, a positioning unit for positioning the intermediate member and one of the members (second housing 56 in the present embodiment) is positioned as a main body fixing screw 91a. , 91b and the like penetrate through, and the drive source holding member, the intermediate member, and the opposing member are fastened together to the main body device.
According to this, positioning of at least one member of the drive source holding member and the opposing member and the intermediate member, fixing of the driving source holding member, the opposing member and the intermediate member, and fixing to the main body device are coaxially performed. It is done. As a result, the drive source holding member, the opposing member, and the intermediate member are fixed to the outside of the positioning portion between at least one member of the drive source holding member and the opposing member and the intermediate member, and further to the main body device on the outside. It is possible to reduce the size of the device as compared with the drive device described in Patent Document 1 in which the device is fixed.

(Aspect 2)
In the first aspect, the positioning portion is provided on one of an intermediate member such as the first housing 66 and one of the members (second housing 56 in the present embodiment), and fastening members such as main body fixing screws 91a and 91b are provided. Cylindrical positioning protrusions 66b1 and 66b2 having through holes such as intermediate screw through holes 161a and 161b, and positioning penetrations such as positioning screw through holes 156a and 156b provided on the other side and into which the positioning protrusions fit. With a hole According to this, as described in the embodiment, a fastening member such as the main body fixing screws 91a and 91b can be penetrated through the positioning portion.

(Aspect 3)
In aspects 1 or 2, the opposing member, such as the second housing 56, is fastened to a drive source holding member, such as the bracket 52.
According to this, when the drive device such as the drive unit 50 is attached to the main body device such as the printer, it is possible to prevent the drive transmission member from coming off from the drive device as described in the embodiment. As a result, the work of assembling the drive device to the main body device can be easily performed.

(Aspect 4)
In any one of aspects 1 to 3, the opposing member such as the second housing 56 has a main body positioning portion such as a main body positioning holes 56a1 and 56a2 that are positioned with respect to the main body device.
According to this, it is possible to satisfactorily mesh with the drive transmission member of the main body device such as a cam gear.

(Aspect 5)
In any one of aspects 1 to 4, the one member is an opposing member such as a second housing.
According to this, an intermediate member such as the first housing 66 can be positioned in the second housing 56.

(Aspect 6)
In any one of aspects 1 to 5, the intermediate member such as the first housing 66 is positioned on the drive source holding member such as the bracket 52 and the opposing member such as the second housing 56.
According to this, the intermediate member such as the first housing 66, the drive source holding member such as the bracket 52, the drive source holding member, and the opposing member such as the second housing 56 can be positioned with each other.

(Aspect 7)
In any one of aspects 1 to 6, the drive transmission member held by the intermediate member such as the first housing 66 is an internal gear.
As described in the embodiment, in the intermediate member such as the first housing 66 provided with the internal gear, it is necessary to provide a positioning portion and a fastening portion on the outer shell of the internal gear, and the intermediate member becomes large in size. There is a risk that the drive unit of the drive unit will become large.
However, in this aspect, since the configuration of the first aspect is provided, it is possible to effectively suppress the increase in size of the intermediate member.

(Aspect 8)
In any one of aspects 1 to 7, the planetary gear mechanism 70 is provided.
According to this, it is possible to suppress the increase in size of the drive device of the drive unit 50 and obtain a large reduction ratio. Further, even if an inexpensive drive source having a low torque is used as the drive source of the drive motor 51 or the like, the drive member such as the cam member 44 can be driven satisfactorily.

(Aspect 8)
In the seventh aspect, the sun gear 62b of the planetary gear mechanism 70 and the carrier 64 holding the plurality of planetary gears 65 are supported by a shaft of a drive source holding member such as the first support shaft 152, and are included in the planetary gear mechanism 70. The tooth gear 66a is provided on an intermediate member such as the first housing 66.
As described in the embodiment, since the internal gear 66a of the planetary gear mechanism 70 includes a plurality of planetary gears 65 and the sun gear 62b, the diameter is increased, and the first housing 66 is also increased accordingly. .. However, in this aspect, since the configuration of the first aspect is provided, the increase in size of the intermediate member can be effectively suppressed, and the increase in size of the drive device such as the drive unit 50 can be suppressed.

(Aspect 9)
In the seventh or eighth aspect, the rotation axis direction of the sun gear 62b of the planetary gear mechanism 70 and the rotation axis direction of the drive source such as the drive motor 51 are orthogonal to each other.
According to this, as described in the embodiment, the sun of the drive device such as the drive unit 50 is compared with the case where the rotation axis direction of the drive source such as the drive motor 51 is parallel to the rotation axis direction of the sun gear 62b. It is possible to suppress the increase in size of the gear 62b in the direction of the rotation axis.

(Aspect 10)
In the ninth aspect, the rotation axis direction of the drive source such as the drive motor 51 is parallel to the side plate such as the back side plate 101 to which the drive device of the main body device is fastened.
According to this, as described in the embodiment, the rotation axis direction of the drive source such as the drive motor 51 is orthogonal to the side plate such as the back side plate 101 to which the drive device of the main body device is fastened. The direction orthogonal to the side plate of the drive device can be shortened. As a result, the gap between the outer cover of the main body device such as a printer and the back side plate 101 can be narrowed, and the main body device can be miniaturized.

(Aspect 11)
In any of aspects 1 to 10, intermediate members such as the first housing 66 are fixed only by co-fastening.
According to this, it is possible to reduce the number of fastening members such as screws, and it is possible to reduce the cost of the drive device.

(Aspect 12)
In any one of aspects 1 to 11, the opposing member such as the second housing 56, the intermediate member such as the first housing 66, and the drive source holding member such as the bracket 52 are fixing guides for holding the drive transmission member arranged in the main body device. It is fastened together with a member such as 110.
According to this, the drive transmission member such as the second output gear 54 that meshes with the drive transmission member such as the cam gear 55 arranged in the main body device of the drive device such as the drive unit 50 is attached to the drive transmission member arranged in the main body device. Can mesh well.

(Aspect 13)
In any one of aspects 1 to 12, the drive source holding member such as the bracket 52 is made of metal, and the fourth outer co-tightening portion is fastened to the metal member of the main body device (in the present embodiment, the back side plate 101). It has a fastening part such as 158d.
According to this, as described in the embodiment, the drive source such as the drive motor 51 can be electrically grounded via the bracket, the fastening member, and the metal member of the main body device.

(Aspect 14)
In any one of aspects 1 to 13, the drive source holding member such as the bracket 52 has three or more fastening portions such as outer co-fastening portions, and one of the plurality of fastening portions is a rotation shaft of the drive source. It was provided on the side opposite to the side where the other fastening portions were provided with the center in between.
According to this, as described with reference to FIG. 28, it is possible to suppress the vibration of the drive source holding member such as the bracket 52 due to the vibration of the drive source of the drive motor 51 during driving.

(Aspect 15)
The drive device according to any one of aspects 1 to 14 in an image forming apparatus including a driving member such as a cam member 44 and a driving device for driving the driving member and forming an image on a recording medium such as a sheet material P. The drive device of was used.
According to this, it is possible to reduce the size of the image forming apparatus.

(Aspect 16)
In the fifteenth aspect, the attachment / detachment unit such as the fixing device 12 which has a drive member such as a cam member 44 and can be attached / detached to the apparatus main body, and the guide groove 114 which guides the attachment / detachment unit when the attachment / detachment unit is attached / detached. A guide holding member such as a fixing guide 110 that has a guide portion such as the above and holds the attachment / detachment unit is provided, and the facing member, the intermediate member, and the drive source holding member are co-tightened to the guide holding member. ..
According to this, the driving force of the driving source such as the driving motor 51 can be satisfactorily transmitted to the driving member such as the cam member 44 included in the attachment / detachment unit such as the fixing device 12.
The detachable unit is not limited to the fixing device 12, but may be a process cartridge 1, a transfer device, or the like, which is configured to be detachable from the device main body.

(Aspect 17)
In aspect 16, the attachment / detachment unit is the fixing device 12.
According to this, the driving force can be satisfactorily transmitted to the driving member such as the cam member 44 included in the fixing device 12.

1: Process cartridge 2: Photoreceptor 3: Charging roller 4: Developing device 5: Cleaning blade 6: LED head array 7: Toner cartridge 8: Developer accommodating unit 9: Developer collecting unit 10: Transfer unit 11: Feeding device 12: Fixing device 12a: Guide protrusion 13: Paper ejection device 14: Transfer roller 15: Feed cassette 16: Feeding roller 17: Resist roller 18: Fixing roller 19: Pressurizing roller 19a: Shaft 20: Paper ejection roller 21 : Paper output tray 22: Container body 23: Infrared heater 30: Transfer frame 37: Open / close cover 40: Pressurization adjustment mechanism 41: Lever member 41a: Support shaft 41b: Spring receiver 42: Cam receiver 43: Spring 44: Cam member 44a : Cam shaft 44b: Cam surface 44c: Parallel pin 45: Rotation angle detection mechanism 45a: Filler 45b: Optical sensor 45c: Opening 46: Bearing 47: Side plate 47a: Spring receiver 50: Drive unit 51: Drive motor 51a: Screw hole 52: Bracket 52a: Positioning protrusion 52b: Positioning protrusion 53: First output gear 54: Second output gear 55: Cam gear 55a: Parallel pin 56: Second housing 56a1: First main body positioning hole 56a2: Second main body positioning hole 56b : Mounting screw through hole 60: Worm gear 61: Worm 62: Planetary drive transmission member 62a: Input gear 62b: Sun gear 63: Carrier holder 63a: Snap fit part 64: Carrier 64a: Supported part 64b: Engagement hole part 64c : Planetary support 65: Planetary gear 66: First housing 66a: Internal gear 66b1: First positioning convex portion 66b2: Second positioning convex portion 66c1: First positioning hole 66c2: Second positioning hole 66d: Shaft through hole 70 : Planetary gear mechanism 71: Drive coupling member 71a: Gear portion 71b: Driven side coupling 71c: Engagement hole 72: Torque limiter 72a: Notch 72b: Engagement protrusion 73: Drive shaft 73a: Press-fitting portion 73b: Support portion 74: Parallel pin 75: Warm wheel 75a: Drive side coupling 75c: Press-fit hole 80: Load application portion 91a: First main body fixing screw 91b: Second main body fixing screw 91c: Third main body fixing screw 91d : Fourth main body fixing screw 92: Housing mounting screw 100: Device main body 101: Back side plate 102a: First main body positioning protrusion 102b: Second main body positioning protrusion 103: Fourth screw hole 110: Fixing guide 111: First fastening boss 111a: First screw hole 112: Second fastening boss 112a: Second screw hole 113: Third fastening boss 113a: Third screw hole 114: Guide groove 151a: First outer screw through hole 151b: Second outer screw through hole 151c: Third outer screw through hole 151d: Fourth outer screw through hole 152: First Support shaft 153: Second support shaft 153a: Screw hole 154: Bearing 155: Motor holding surface 155a: Notch 155b: Screw through hole 156a: First positioning screw through hole 156b: Second positioning screw through hole 156c: Inner screw through Hole 157a: 1st inner co-tightening part 157b: 2nd inner co-tightening part 157c: 3rd inner co-tightening part 158a: 1st outer co-tightening part 158b: 2nd outer co-tightening part 158c: 3rd outer co-tightening part 158d : Fourth outer co-tightening portion 161a: First intermediate screw through hole 161b: Second intermediate screw through hole 161c: Third intermediate screw through hole 164: Drive connection convex portion 166a: First intermediate co-tightening portion 166b: Second intermediate Co-tightening part 166c: Third intermediate co-tightening part 171: Driven side engaging protrusion 175: Driving side engaging protrusion P: Sheet material

Japanese Unexamined Patent Publication No. 2012-82842

Claims (17)

With the drive source
A plurality of drive transmission members that transmit the driving force of the drive source to the drive members,
A drive source holding member that holds the drive source and
Opposing members facing the drive source holding member with at least one drive transmission member sandwiched between them.
An intermediate member arranged between the drive source holding member and the facing member, positioned on at least one of the driving source holding member and the facing member, and having one of a plurality of the driving transmission members. In the provided drive unit
Together when the intermediate member and the positioning portion fastening member penetrates to position and said one member, and the driving source holding member and the intermediate member and the opposing member is fastened to the main unit by fastening together
NS,
The drive source holding member, the intermediate member, and the opposite member are drive transmissions arranged in the main body device.
A drive device characterized in that it is fastened together with a member that holds a reaching member. In the drive device according to claim 1,
The positioning portion is provided on one of the intermediate member and the one member, and is provided on the other side of the tubular positioning convex portion having a through hole through which the fastening member penetrates, and the positioning convex portion is fitted. A drive device having a positioning through hole.
In the drive device according to claim 1 or 2.
The drive device, wherein the facing member is fastened to the drive source holding member. In the drive device according to any one of claims 1 to 3.
The facing member is a drive device having a main body positioning portion positioned with respect to the main body device. In the drive device according to any one of claims 1 to 4.
A drive device in which one of the members is the opposite member. In the drive device according to any one of claims 1 to 5,
The driving device is characterized in that the intermediate member is positioned on the driving source holding member and the opposing member. In the drive device according to claim 6,
A drive device characterized in that the drive transmission member included in the intermediate member is an internal gear. In the drive device according to any one of claims 1 to 7.
A drive device having a planetary gear mechanism. In the drive device according to claim 8,
A drive device characterized in that the drive transmission member included in the intermediate member is an internal gear of the planetary gear mechanism. In the drive device according to claim 8 or 9.
A drive device characterized in that the rotation axis direction of the sun gear of the planetary gear mechanism and the rotation axis direction of the drive source are orthogonal to each other. In the drive device according to claim 10,
A drive device characterized in that the direction of rotation of the drive source is parallel to the side plate to which the drive device of the main body device is fastened. In the drive device according to any one of claims 1 to 11.
The driving device is characterized in that the intermediate member is fixed only by co-tightening. In the drive device according to any one of claims 1 to 12.
The drive source holding member is a drive device made of metal and having a fastening portion to be fastened to the metal member of the main body device. In the drive device according to any one of claims 1 to 13.
The drive source holding member has three or more fastening portions, and one of the plurality of fastening portions is on a side opposite to the side on which the other fastening portion is provided with the center of the rotation axis of the drive source interposed therebetween. A drive device characterized by being provided. With the drive member
In an image forming apparatus provided with a driving device for driving the driving member and forming an image on a recording medium,
An image forming apparatus according to any one of claims 1 to 14, wherein the driving device according to any one of claims 1 to 14 is used as the driving device. In the image forming apparatus according to claim 15,
A detachable unit having the drive member and detachable from the device body,
A guide portion for guiding the detachable unit when attaching / detaching the detachable unit is provided, and a guide holding member for holding the detachable unit is provided.
An image forming apparatus characterized in that the facing member, the intermediate member, and the drive source holding member are co-tightened to the guide holding member. In the image forming apparatus according to claim 16,
An image forming apparatus, wherein the attachment / detachment unit is a fixing device.

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