JP2012078633A - Reciprocation driver and image forming apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize inversion switching behavior of a reciprocation driver.SOLUTION: The reciprocation driver includes: input means; a first transmission member comprising a planet gear; a second transmission member comprising a planet gear; a member to be driven which can reciprocate; a first inner gear which forms a part of the first transmission member and changes drive transmission from the first transmission member to the member to be driven; a second inner gear which forms a part of the second transmission member and changes drive transmission from the second transmission member to the member to be driven; engaging means which is engaged with one of the first and second inner gears; and switching means for switching an engaging direction of the engaging means.

Description

  The present invention relates to a reciprocating drive device and an image forming apparatus including the same.

  The present applicant has previously proposed a reciprocating drive device that converts a unidirectional motion into a reciprocating motion (Patent Document 1). This is because the input means, the first transmission member that rotates in the forward direction, the second transmission member that rotates in the reverse direction, the driven member that can reciprocate, and the drive of either the first or second transmission member Switching auxiliary means for positioning the first and second transmission members so as to be transmitted to the driven member. And switching means formed on the driven member to control the switching timing of the first and second transmission members, and converting the drive from the input means into the reciprocating motion of the driven member. It is a feature.

  An example of using such a reciprocating drive device is a separation claw drive device provided in an image forming apparatus.

JP 60-260757 A

  In the above prior art, further stabilization of the reversal switching behavior is desired. The present invention is a further development of the above prior art. An object of the present invention is to provide a reciprocating drive device in which reversal switching behavior is stabilized, and an image forming apparatus including the reciprocating drive device.

  In order to achieve the above object, a typical configuration of a reciprocating drive device according to the present invention includes an input means for receiving an input of a driving force, a first transmission member comprising a planetary gear, and a second construction comprising a planetary gear. A transmission member, a driven member capable of reciprocation, and a first internal gear that forms part of the first transmission member and changes drive transmission from the first transmission member to the driven member; , A second internal gear that forms part of the second transmission member and changes drive transmission from the second transmission member to the driven member, the first internal gear, and the second It is characterized by comprising engagement means for engaging with any of the internal gears, and switching means for switching the engagement direction of the engagement means.

  According to the reciprocating drive device of the present invention, reverse switching driving can be performed without impact force on the driven member. That is, it is possible to provide a reciprocating drive device in which the reverse switching behavior is stabilized.

Schematic configuration diagram of image forming apparatus of embodiment A perspective view of a photosensitive drum, a cleaning device, and a reciprocating drive device as a driving means for a separation claw Fig. 2 arrow a view B arrow view of FIG. Bird's eye view of reciprocating drive B arrow view of FIG. Rear view of FIG. Exploded perspective view of gears constituting reciprocating drive device (Part 1) Exploded perspective view of gears constituting reciprocating drive device (Part 2) The figure explaining the switching operation of a reciprocating drive device (the 1) The figure explaining the switching operation of a reciprocating drive device (the 2) The figure explaining the switching operation of a reciprocating drive device (the 3) The figure explaining the displacement behavior of a nail of a reciprocating drive device Configuration diagram of reciprocating drive device of embodiment 2

[Example 1]
Hereinafter, a reciprocating drive device according to an embodiment of the present invention and an image forming apparatus including the reciprocating drive device will be described with reference to the drawings. The reciprocating drive device will be described below as an application example as a driving means for reciprocating a separation claw for separating transfer paper from a photosensitive drum provided in the image forming apparatus in the longitudinal direction of the photosensitive drum. However, the reciprocating drive means is not limited to this application example, and can be applied to a drive means for reciprocating the separation claw provided in the fixing device.

(1) Schematic Configuration of Example Image Forming Apparatus FIG. 1 is an overall configuration diagram of an image forming apparatus 100 according to the present embodiment. This apparatus 100 is an electrophotographic copying machine. A is an apparatus main body of the image forming apparatus 100, and B is a document reading apparatus mounted on the upper part of the apparatus main body A. An electrophotographic image forming mechanism is disposed in the apparatus main body A. The document reading device B has a document feeding device B1 and a document scanning device B2.

  The original is conveyed by the apparatus B1 onto the original platen glass 20 of the apparatus B2 and placed with the image surface facing downward. Then, the image of the document is scanned by a scanning optical system 24 including a document illumination light source 21, a mirror 22, a lens 23, etc., is photoelectrically read by a solid-state imaging device 25, is subjected to image processing by an image processing unit 26, and an image memory 27 Is input.

  In the apparatus main body A, a rotatable photosensitive drum 101 as a latent image carrier (image carrier) is driven to rotate in a clockwise direction indicated by an arrow at a predetermined speed. The surface of the drum 101 is uniformly charged by the charger 2. The surface of the drum 101 is exposed to image information by a writing optical system 9 including a laser unit 7 and a mirror 8.

  In this exposure, image information is input from the image memory 27 to the laser unit 7, and the laser unit 7 outputs a laser beam modulated in accordance with the input image information to scan and expose the surface of the drum 101 (light irradiation). Is done. Thereby, an electrostatic latent image corresponding to the image information is formed on the surface of the drum 101. The charger 2 and the writing optical system 9 constitute a latent image forming unit.

  Next, when the electrostatic latent image on the drum 101 passes the position facing the developing device 10, the electrostatic latent image is visualized by the selective adhesion of toner and becomes a toner image. Reference numeral 10 a denotes a toner replenishing unit for the developing device 10. This toner image is superposed on the transfer paper (recording material) P conveyed from the paper feed cassette 11 or the manual feed tray 12 and transferred onto the transfer paper by a transfer device 13 as transfer means. The transfer paper P on which the toner image is transferred is sent to the fixing device 15 by the transport belt 14. The transferred toner image is fixed as a fixed image on the transfer paper by passing through the fixing device 15.

  The transfer paper P that has passed through the fixing device 15 is sent to the paper discharge unit 16 as an image formed product. On the other hand, the surface of the drum 101 after the image transfer to the transfer paper P is repeatedly subjected to image formation after residual toner and the like are removed by the cleaning device 110.

(2) Reciprocating Drive Device A separation claw 102 is disposed opposite to the drum 101 on the downstream side of the transfer device 13 in the drum rotation direction and on the upstream side of the cleaning device 110 in the drum rotation direction. The separation claw 102 serves to separate the transfer paper P that has passed through the position of the transfer unit 13 and is in close contact with the surface of the drum 101 from the surface of the drum 101. In this embodiment, the reciprocating drive device 200 according to the present invention is applied as a driving means for reciprocating the separation claw 102 in the longitudinal direction of the drum 101 (in the drum bus direction).

  In the present embodiment, a reciprocating drive device (hereinafter referred to as a drive unit) 200 is disposed with respect to the cleaning device 110 as shown in FIG. 3 is a view taken in the direction of arrow a in FIG. 2, and FIG. 4 is a view taken in the direction of arrow b in FIG. The tip of the separation claw 102 is in contact with the surface of the drum 101. Further, the claw holding member 103 that holds the separation claw 102 is held by a guide member 104 provided in the cleaning device 110, and is slidable in the X direction that is the longitudinal direction of the drum 101 with respect to the cleaning device 110. It is supported.

  On the other hand, the drive unit 200 is configured to reciprocate the rack 201 in the X direction by receiving a drive from a drive gear (drive source) 111 on the cleaning device 110 side. The connection pin 201 a of the rack 201 is connected to the claw holding member 103. As a result, the claw holding member 103 reciprocates together with the rack 201, and the separation claw 102 reciprocates in the X direction, which is the longitudinal direction of the drum 101.

  Next, details of the drive unit 200 will be described. 5 is a bird's-eye view of the drive unit 200, FIG. 6 is a view taken in the direction of arrow B in FIG. 5, and FIG. 7 is a rear view of FIG. The drive unit 200 includes an input gear 203, a second input gear 204, a third input gear 205, a first planetary gear unit 210, and a second planetary gear that are rotatably supported by housings 202a and 202b as drive transmission means. A unit 220 is provided. Furthermore, an idle gear 206, an output gear large gear portion 207, an output gear small gear portion 208, a pinion gear 209, a rack 201 slidably supported by the housings 202a and 202b, and the like are provided.

  In the above, the input gear 203 is an input unit that receives a driving force from the driving gear (driving source) 111. The first planetary gear unit 210 is a transmission member for the driving force, and is a first transmission member made of a planetary gear. The second planetary gear unit 220 is a transmission member for the driving force, and is a second transmission member made of a planetary gear. The rack 201 is a driven member that can reciprocate.

  As shown in FIGS. 8 and 9, the first planetary gear unit 210 includes a sun gear 211, a carrier 212, an internal gear 213, and planetary gears 214a and 214b. The sun gear 211, the carrier 212, and the internal gear 213 are rotationally supported coaxially with each other, and the planetary gears 214a and 214b are rotationally supported by the rotational support portions 212a and 212b of the carrier 212.

  As a specific drive transmission path, the drive is transmitted in the order of the input gear 203, the first transmission gear 204, the second transmission gear 205, and the sun gear 211. The sun gear 211 and the planetary gears 214a and 214b, and the planetary gears 214a and 214b and the internal teeth 213a of the internal gear 213 communicate with each other.

  The configuration and transmission path of the second planetary gear unit 220 are the same as those of the first planetary gear unit 210. 8 and 9, the reference numerals in parentheses are the reference numerals of the constituent members on the second planetary gear unit 220 side. The outer teeth 214c and 224c of the carriers 212 and 222 of the first planetary gear unit 210 and the second planetary gear unit 220 are engaged with each other. The external gear 214c, the idle gear 206, and the large gear portion 207 of the output gear communicate with each other, and the large gear portion 207 of the output gear and the small gear portion 208 of the output gear are transmitted coaxially. Further, the small gear portion 208 of the output gear, the pinion 209, and the rack 201 communicate with each other.

  Next, a reciprocal drive switching configuration will be described. The lever 230 is supported so as to be rotatable about the support shaft 230a with respect to the housings 202a and 202b. The lever 230 includes claws 231a and 231b, and is configured to engage with any of the teeth 213b and 223b of the internal gears 213 and 223.

  Further, the elastic member 240 included in the housings 202a and 202b is supported in a state in which a predetermined deformation is given in advance. Further, the elastic member 240 is attached to the slit 232 provided at one end of the lever 230. Accordingly, the engagement direction of the claws 231a and 231b of the lever 230 is determined to be one of the teeth 213b and 223b depending on the deformation direction of the elastic member 240.

  For example, as shown in FIG. 6, when the claw 231a is engaged with the teeth 213b and the rotation of the internal gear 213 is restricted, the drive input from the second transmission gear 205 is the first planetary gear unit. It is transmitted only to the carriers 212 belonging to 210. Then, the drive is transmitted to the rack 201 after the idle gear 206 through the external teeth 214c.

  On the other hand, when the claw 231b is engaged with the teeth 223b and the rotation of the internal gear 223 is restricted, the drive input from the second transmission gear 205 is only to the carrier 222 belonging to the second planetary gear unit 220. Communicated. The drive is transmitted from the idle gear 206 to the rack 201 through the external teeth 224c and 214c. That is, the moving direction of the rack 201 is reversed depending on the engaging direction of the claws.

  In addition, in order to switch the engagement direction of the lever 230, the rack 201 is provided with pressing portions 201b and 201c that change the deformation direction of the elastic member 240. The pressing parts 201b and 201c straddle the elastic member 240 and are arranged on a trajectory where the pressing parts 201b and 201c are movable.

  Next, the switching operation of the reciprocating drive will be described based on FIGS. 10A, 10B, and 10C. In the state shown in FIG. 10A, the claw 231a engages with the teeth 213b to restrain the rotation of the internal gear 213, so that the drive is transmitted only to the carrier 212 of the first planetary gear unit 210, and the rack 201 is Move in the Y direction.

  FIG. 10B is a diagram illustrating a state where the pressing portion 201b starts to contact the elastic member 240 as the rack 201 moves in the Y direction. The pressing part 201b further deforms the elastic member 240 in the Y direction by further moving in the Y direction. Thereafter, the elastic member 240 jumps and generates a buckling phenomenon, and shifts to a deformed state opposite to the initial direction.

  In the state of FIG. 10C, the claw 231b engages with the teeth 223b to restrain the rotation of the internal gear 223, so that the drive is transmitted only to the carrier 222 of the second planetary gear unit 220, and the rack 201 is moved from the Y direction. Switch and move instantly in the Z direction. As the subsequent operation, the pressing portion 201c switches the deformation direction of the elastic member 240 again (not shown), and the moving direction of the rack 201 is reversed, so that the state shown in FIG. 10A is restored.

  In the above, the internal gear 213 forms a part of the first planetary gear unit 210 and is a first internal gear that changes the drive transmission from the first planetary gear unit 210 to the rack 201 that is a driven member. The internal gear 223 forms a part of the second planetary gear unit 220 and is a second internal gear that changes the drive transmission from the second planetary gear unit 220 to the rack 201. The lever 230 is an engaging means for engaging with either the first internal gear 213 or the second internal gear 223. The elastic member 240 and the pressing portions 201b and 201c are switching means for switching the engaging direction of the engaging means 230.

  In the switching means, the elastic member 240 is a positioning means for positioning the engaging direction of the engaging means 230, and the pressing portions 201b and 201c are pressing means for changing the phase of the positioning means.

  FIG. 11 is a diagram illustrating the displacement behavior of the rack 201 or the separation claw 102 when the reciprocating drive device 200 of this embodiment is applied. As shown in the figure, in the reciprocating operation switching unit (extreme value in the graph), the displacement does not change suddenly, and the reciprocating switching motion can be realized more stably and at a constant speed compared to the conventional example. As described above, it is possible to prevent drum surface flaws by providing a reciprocating drive device capable of making the contact time of the separation claw 102 uniform with respect to the drum 101.

[Example 2]
Further, another embodiment of the switching configuration according to the present invention will be described. FIG. 12 is a diagram illustrating a switching configuration according to the present embodiment. In contrast to the first embodiment, a solenoid (actuator) 250 is used as means for switching the engagement direction of the lever 230. The lever 230 and the solenoid 250 are linked by a joint 233 in the drawing.

  The solenoid 250 is turned on / off by a power supply unit controlled by the control circuit unit 300. As a result of the operation of the plunger, the lever 230 is engaged with the direction in which the claw 231a engages with the tooth 213b of the internal gear 213 around the support shaft 230a, and the claw 231b engages with the tooth 223b of the internal gear 223. The engagement direction is selectively controlled to switch to the matching direction. Thereby, since drive switching can be controlled at an arbitrary timing with respect to the first embodiment, there is an advantage that the application range can be expanded to an apparatus that requires sequential reciprocating drive switching.

  In the first and second embodiments, the reciprocating drive device according to the present invention is applied as a driving unit that reciprocally moves the separation claw 102 for separating the transfer paper P from the drum 101 in the longitudinal direction of the drum 101. It was. The reciprocating drive device according to the present invention can be applied to other configurations that perform reciprocating motion.

  For example, in an image forming apparatus having a rotatable fixing member for contacting a recording material and fixing a toner image as a fixed image, and a separation claw for separating the recording material from the fixing member, the separation claw of the fixing member It can be applied as drive means for reciprocating in the longitudinal direction. In addition, the cleaning device 110 can be applied as a driving means for reciprocating the cleaning blade in the longitudinal direction of the drum 101. In these cases, the same effects as those of the first and second embodiments can be obtained by using the configuration of the present invention.

  As described above, by using a planetary gear as a switching means for reciprocating driving, it is possible to perform reverse switching driving without directly impacting the driven member, to stabilize the claw behavior and to prevent drum surface wrinkles associated therewith. Became possible.

  200 .. Reciprocating drive device, 203... Input means, 210... First transmission member, 220... Second transmission member, 201... Driven member, 213 ... First internal gear, 223 Second internal gear, 230... Engagement means, 240, 201b, 201c, 250.

Claims (6)

An input means for receiving an input of driving force;
A transmission member for the driving force, a first transmission member comprising a planetary gear;
A transmission member for the driving force, a second transmission member comprising a planetary gear;
A driven member capable of reciprocating;
A first internal gear that forms part of the first transmission member and changes drive transmission from the first transmission member to the driven member;
A second internal gear that forms part of the second transmission member and changes drive transmission from the second transmission member to the driven member;
Engagement means for engaging with either the first internal gear or the second internal gear;
Switching means for switching the engaging direction of the engaging means;
A reciprocating drive device comprising:   The reciprocating drive device according to claim 1, wherein the switching unit includes an actuator.   The switching means comprises positioning means made of an elastic member for positioning the engaging direction of the engaging means, and pressing means for changing the phase of the positioning means. 2. A reciprocating drive device according to 1.   The reciprocating drive device according to claim 3, wherein the pressing means is formed on the driven member.   A rotatable image carrier, image forming means for forming a toner image on the image carrier, and separation for separating a recording material applied to the image carrier for transferring the toner image from the image carrier 5. An image forming apparatus having a nail and a driving unit that reciprocates the separation claw in a longitudinal direction of the image carrier, wherein the driving unit is a reciprocating drive according to claim 1. An image forming apparatus comprising the apparatus.   Image forming means for forming a toner image on a recording material, a rotatable fixing member for contacting the recording material and fixing the toner image as a fixed image, and a separation claw for separating the recording material from the fixing member And a driving unit that reciprocally moves the separation claw in the longitudinal direction of the fixing member, wherein the driving unit is a reciprocating driving device according to any one of claims 1 to 4. An image forming apparatus characterized by being configured as described above.