JP2006053465A - Rotary drive unit and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide rotary drive units each of which ensures the ground of a rotated body through a rotary shaft and to provide an image forming apparatus suitable to use the rotary drive unit. <P>SOLUTION: Each rotary drive unit includes: a drive source for generating rotary drive force; the rotary shaft adapted to transmit the rotary drive force of the drive source to the rotated body and connected to the rotation center of the rotated body; a support member for pivotally supporting the rotary shaft such that the rotary shaft is freely rotated; a housing having a front part and a rear part, which are inserted from a predetermined direction into a mounting hole disposed on a frame between the drive source and the rotated body such that the front part is situated further forward than the mounting hole in the predetermined direction and the rear part is situated further backward than the mounting hole in the predetermined direction and thus the rotary shaft is passed through the housing in the predetermined direction and the support member is accommodated in it; and a ground member attached to the housing so as to be in contact with the rotary shaft inside the housing, and having legs extending out further backward in a predetermined direction than the frame of the housing from the back of the housing. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rotational drive unit that rotationally drives a member to be rotated, and an image forming apparatus provided with such a rotational drive unit.

  Conventionally, an image forming apparatus that forms a toner image on a rotating photosensitive member, and finally forms an image composed of the toner image fixed on the recording medium by transferring and fixing the toner image on the recording medium. It has been known.

  Such an image forming apparatus is provided with a rotational drive unit that rotationally drives the photosensitive member (see, for example, Patent Document 1). In the rotation drive unit described in Patent Document 1, a rotation shaft is inserted into an insertion hole of a frame disposed between a motor and a photoreceptor, and the photoreceptor is driven to rotate.

  In an image forming apparatus equipped with such a rotation drive unit, a motor is arranged on the apparatus rear side so that the photoreceptor can be easily accessed in consideration of maintenance of the photoreceptor and the rotation shaft is moved from the apparatus rear side to the apparatus front. Some image forming apparatuses have a configuration in which the photosensitive member is passed through the rotating shaft on the front side of the apparatus. Further, there is one in which a ground member is brought into contact with a rotating shaft extending to the front side.

  Here, in the rotary drive unit in which the rotating shaft extending from the rear side to the front side passes through the photosensitive member and extends further to the front side than the photosensitive member, the user accesses the photosensitive member from the front side for maintenance of the photosensitive member. In doing so, there is a possibility that the earth member may be touched, which is dangerous.

  Therefore, it is conceivable that the grounding member is pulled out from the frame toward the insertion hole and is grounded on the rear side by contacting the rotating shaft inserted through the insertion hole.

  However, if this is done, contact accidents by the user can be avoided, but when the rotary shaft is inserted into the insertion hole provided in the frame, the rotary coupling or the driving coupling on the shaft and the ground member collide, There is a problem that it becomes difficult to secure the ground due to deformation.

The above problem is not limited to the rotary drive unit in which the ground member is brought into contact with the rotating shaft electrically connected to the photosensitive member by penetrating the photosensitive member. This is a problem that may occur even in a rotary drive unit in which a ground member is brought into contact with an electrically connected rotary shaft.
JP-A-5-53381

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a rotary drive unit in which the ground of a rotating object is secured through a rotary shaft, and an image forming apparatus suitable for using the rotary drive unit.

To achieve the above object, the rotary drive unit of the present invention comprises:
In the rotational drive unit that rotationally drives the rotating object,
A drive source that generates rotational driving force;
A rotating shaft connected to the rotation center of the rotated body, which transmits the rotational driving force generated by the drive source to the rotated body;
A support member that rotatably supports the rotating shaft;
Inserted from a predetermined direction into a mounting hole provided in a frame disposed between the drive source and the rotated body, and a front portion positioned on the front side in the predetermined direction from the mounting hole; A housing having a rear portion located on the rear side in a predetermined direction, the rotating shaft penetrating in the predetermined direction, and housing the support member therein,
The housing is attached to the housing, has a leg portion that contacts the rotating shaft inside the housing, and extends from the rear portion of the housing to the outside of the housing in the predetermined direction behind the frame. And a ground member.

  In the rotary drive unit of the present invention, the ground member has a portion that contacts the rotating shaft inside the housing, and the leg of the ground member is inserted into the mounting hole rather than the mounting hole provided in the frame. It is provided at the rear side in the predetermined direction, that is, at a position where it is not necessary to pass through the mounting hole.

  Thus, according to the rotary drive unit of the present invention, when the rotary shaft is inserted into the mounting hole provided in the frame, the deformation due to the collision between the ground member and another member, in particular, the function as the ground is achieved. Since it is possible to avoid significant deformation of the contact portion with the rotation shaft and the leg portion, it is possible to secure the ground of the rotated body through the rotation shaft.

In order to achieve the above object, an image forming apparatus of the present invention comprises:
An electrostatic latent image is formed on the rotating image carrier, and the electrostatic latent image is developed with toner to obtain a toner image on the image carrier. The toner image is finally transferred onto a recording medium and In an image forming apparatus for forming an image composed of a toner image fixed on the recording medium by fixing,
A frame disposed between the drive source and the image carrier and having a predetermined mounting hole;
A rotational drive unit for rotationally driving the image carrier,
The rotational drive unit is
A drive source that generates rotational driving force;
A rotating shaft connected to the rotation center of the image carrier, which transmits the rotational driving force generated by the drive source to the image carrier;
A support member that rotatably supports the rotating shaft;
Inserted from a predetermined direction into a mounting hole provided in a frame disposed between the drive source and the rotated body, and a front portion positioned on the front side in the predetermined direction from the mounting hole; A housing having a rear portion located on the rear side in a predetermined direction, the rotating shaft penetrating in the predetermined direction, and housing the support member therein,
The housing is attached to the housing, has a leg portion that contacts the rotating shaft inside the housing, and extends from the rear portion of the housing to the outside of the housing in the predetermined direction behind the frame. A grounding member is provided.

  According to the image forming apparatus of the present invention, it is possible to avoid deformation due to a collision between the ground member and another member when the rotating shaft is inserted into the mounting hole. Can be secured.

Here, the housing has a key extending in the predetermined direction on the outer periphery,
The frame preferably has a key hole through which the key is inserted when the housing is inserted into the mounting hole from a predetermined direction.

  For example, even if the ground member is exposed from the housing between the portion that contacts the rotating shaft and the leg portion, and the exposed portion passes through the mounting hole at the time of mounting, this is done. As a result, collision between the exposed portion and the frame can be avoided and damage to the exposed portion can be prevented. As a result, the grounding of the image carrier can be more reliably ensured through the rotating shaft.

  According to the image forming apparatus of the present invention provided with the rotation drive unit of the present invention, the ground of the image carrier can be secured through the rotation shaft.

  Hereinafter, embodiments of the rotational drive unit of the present invention and the image forming apparatus of the present invention will be described.

  FIG. 1 is a schematic configuration diagram of an embodiment of an image forming apparatus according to the present invention, which includes an embodiment of a rotational drive unit according to the present invention.

  The printer 1 of the present embodiment illustrated in FIG. 1 includes a transfer unit 110 and image forming units 1Y and 1M that respectively form Y (yellow), M (magenta), C (cyan), and K (black) toner images. 1C, 1K, a fixing unit 120, a paper transport unit 130, and a paper tray unit 140.

  The image forming units 1Y, 1M, 1C, and 1K are arranged in the order of Y (yellow), M (magenta), C (cyan), and K (black) from the right side in FIG. , 11M, 11C, 11K, LEDs 112Y, 112M, 112C, 112K, which are exposure devices that emit exposure light for each color, and electrostatic latent images formed by LEDs on the surface of the photoreceptor roll are developed with toner images of each color The developing rolls 113Y, 113M, 113C, and 113K are configured respectively.

  The transfer unit 110 is disposed so that the intermediate transfer belt 111 onto which the toner images formed on the color photoconductor rolls are transferred in an overlapping manner, and the intermediate transfer belt 111 circulate along a predetermined route (in the direction of arrow B). A roller 110 a and a secondary transfer roller 112 that secondarily transfers a toner image primarily transferred onto the intermediate transfer belt 111 onto a recording sheet conveyed along a sheet conveyance path 131.

  The fixing unit 120 includes a pressure roll 122 and a heating roll 121 that are arranged to face each other.

  The paper tray unit 140 includes a paper tray 141, a pickup roller 142 that pulls out the recording paper from the paper tray 141, and a feed roller 143 that guides the recording paper drawn out by the pickup roller 142 to the paper transport path 131.

  The paper transport unit 130 is disposed along the paper transport path 131, the transport roller 132 that is disposed along the paper transport path 131 and transports the recording paper, and discharges the recording paper after image formation is performed on the upper surface of the housing 1a. It is comprised by the discharge roller 133 to perform.

  In forming a full-color image in the printer 1, first, the photoreceptor roll 11Y is charged by a charger (not shown), and exposure according to the image signal is performed by the yellow LED 112Y to form a latent image. The latent image is developed with yellow toner by the developing roll 113Y, and a yellow toner image is formed on the photoreceptor roll 11Y. The toner image is primarily transferred to the intermediate transfer belt 111 by a transfer device (not shown).

  The intermediate transfer belt 111 circulates in the direction of arrow B, and is synchronized with the timing at which the yellow toner image transferred onto the intermediate transfer belt 111 reaches the transfer device arrangement position provided for magenta of the next color. A magenta toner image is formed on the photoreceptor roll 111M so that the magenta toner image reaches the transfer device arrangement position. The magenta toner image formed in this way is transferred onto the yellow toner image on the intermediate transfer belt 111 by the transfer device.

  Subsequently, cyan and black toner images are formed at the same timing as described above, and sequentially transferred onto the yellow and magenta toner images on the intermediate transfer belt 111.

  Thus, the multi-color toner image transferred onto the intermediate transfer belt 111 is secondarily transferred by the secondary transfer roller 112 to the recording paper pulled out from the paper tray 141 in time.

  The recording sheet on which the multicolor toner image is transferred is conveyed to the fixing unit 120 along the sheet conveyance path 131 and is heated and pressurized. As a result, the multicolor toner image is fixed on the recording sheet.

  FIG. 2 is an external perspective view of the photoreceptor roll and a rotation drive unit that rotates the photoreceptor roll.

  FIG. 2 shows, in order from the right side, photoconductors 11Y, 11M, 11C, and 11K, and rotational drive units 10Y, 10M, 10C, and 10K, which are components of the image forming units 1Y, 1M, 1C, and 1K. ing. The yellow rotational drive unit 10Y will be described below as a representative.

  The rotational drive unit 10Y shown in FIG. 2 includes a motor M, and decelerates the rotation of the motor M and transmits it to the photoreceptor shaft, which is also an output shaft, thereby rotationally driving the photoreceptor roll penetrated by the photoreceptor shaft. To do. In addition to the motor M, the rotational drive unit 10Y accommodates a photoreceptor shaft 14Y, a planetary speed reducer 12Y that decelerates the rotation of the motor M, and a bearing that supports the photoreceptor shaft 14Y inserted through the planetary speed reducer 12Y. The inlay portion 13Y and the rotation of the photosensitive shaft 14Y are engaged with the photosensitive roll 11Y that is movable in the extending direction but is not allowed to move in the rotational direction around the photosensitive shaft 14Y. Are coupled to the photoconductor 11Y, and a spring 16Y that pushes back the coupling 15Y that has been pushed by the photoconductor roll 11Y to the base side of the photoconductor shaft 14Y.

  3 is an external perspective view of the rotary drive unit shown in FIG.

  FIG. 3 shows the rotary drive units 10Y, 10M, 10C, and 10K for each color, and a predetermined portion 100a of the housing 1a to which the rotary drive units 10Y, 10M, 10C, and 10K are attached.

  3 is provided with an opening 101a through which the spigot part 13K of the rotary drive unit 10K is inserted.

  The rotary drive unit 10K is fixed to the housing 1a by screwing the case 121K of the planetary reduction gear 12K to the predetermined portion 100a. At this time, the inlay part 13K has an opening 101a provided in the predetermined portion 100a. I will go through.

  FIG. 3 also shows a key portion 1312K provided in the case 131K constituting the spigot portion 13K and a notch portion 1011a formed in a part of the opening 101a of the predetermined portion 100a for inserting the key portion 1312K. Are described later. The case 121K of the planetary speed reducer 12K is provided with an attachment portion 1211K for attaching the planetary speed reducer 12K to the predetermined portion 100a. Further, the case 131K of the inlay portion 13K and the case 121K of the planetary reduction gear 12K correspond to an example of a housing according to the present invention.

  FIG. 4 is an external perspective view of the rotary drive unit for each color from below.

  FIG. 4 shows a state in which the ground member 132K is fixed to the protruding portion 1311K provided in the case 131K of the inlay portion 13K by the screw 133K.

  Further, FIG. 4 shows a state in which one forked portion 1322K (see FIG. 5) of the ground member 132K enters the case 131K and the leg portion 1321K which is the other forked portion extends in the lateral direction. It is shown. Note that a part of the leg portion 1321K extending in the lateral direction of the ground member 132K is partly in contact with the predetermined portion 100a when the planetary reduction gear 12K is attached to the predetermined portion 100a of the housing 1a. In the printer 1, the ground of the photoreceptor roll 11K is taken by the housing 1a through the photoreceptor shaft 14K.

  FIG. 5 is a diagram showing a case where the rotary drive unit for Y color is viewed from above.

  In FIG. 5, the photosensitive shaft 14Y passes through the spigot portion 13Y and is inserted into the planetary speed reducer, and a bearing 122Y provided in the planetary speed reducer 12Y and a bearing 134Y provided in the spigot portion 13Y. The state of being supported by is shown. The inlay portion 13Y is essential for supporting the photoreceptor shaft 14Y in the rotational drive unit 1Y that transmits the rotation of the motor decelerated by the planetary speed reducer 12Y to the photoreceptor shaft 14Y through which the photoreceptor roll 11Y is inserted. Is a component to be

  The coupling 15Y also shown in FIG. 5 is attached by a pin 151Y so that the movement in the axial direction is possible within a predetermined range, although the movement in the rotation direction around the photoreceptor shaft 14Y is restricted. The spring 16Y shown in FIG. 5 also moves the coupling 15Y when the photoconductor roll 11Y (not shown) is inserted into the photoconductor shaft 11Y and the coupling 15Y is pushed into the planetary speed reducer 12Y. An urging force is applied toward the tip of the photoreceptor shaft 14Y. By doing in this way, when the photoreceptor roll 11Y is inserted into the photoreceptor shaft 14Y, the engagement with the coupling 15Y can be surely performed. The key portion 1312Y provided in the case 131Y constituting the inlay portion 13Y is longer on the spring side than the protruding portion 1311Y of the case 131Y, but this does not match the shape of the opening 101a. This is a measure for protecting the intermediate portion of the ground member 132Y fixed to the protruding portion 1311 when trying to pass through.

  6 is a cross-sectional view of the inlay portion taken along the line F-F shown in FIG. 5.

  In FIG. 6, a ground member 132Y is attached to the protruding portion 1311Y of the case 131Y, and a forked portion 1322Y of the ground member 132Y entering the case 131Y via a notch 1313Y provided below the case 131Y. A state of being in contact with the photoreceptor shaft 14Y is shown. In this printer 1, the notch 1313Y of the case 131Y of the inlay part 13Y is laterally oriented and downwards in other cases, but this prevents toner, dust, etc. from entering and the ground contact member 1322Y from being abnormally worn. It is to make it.

  In the rotary drive unit 10 of the printer 1 of the present embodiment described above, the ground member 132 has a portion that contacts the rotary shaft 14 inside the case 131, and the leg portion 1321 of the ground member 132 is provided in the predetermined portion 100a. It is provided at a position where it is not necessary to pass through the formed opening 1011a.

  Thereby, according to the printer of this embodiment, when the photosensitive member shaft 14 is inserted through the opening 101a provided in the predetermined portion 100a of the housing 1a, the deformation due to the collision between the ground member 132 and another member, in particular, Since it is possible to avoid the deformation of the forked portion 1322 and the leg portion 1321 of the contact portion with the photoreceptor shaft 14 which is important for fulfilling the function as the ground, it is possible to secure the ground of the photoreceptor roll 11 through the photoreceptor shaft 14. it can.

  The case 131Y constituting the inlay part 13Y is provided with a key part 1312Y, and a notch part 1011a for inserting the key part 1312Y is formed in a part of the opening 101a of the predetermined part 100a. Therefore, in order to attach the planetary speed reducer 12 to the predetermined part 100a of the housing 1a, when the spigot 13Y passes through the opening 101a provided in the predetermined part 100a, the photoreceptor shaft is fitted. 14 can be prevented from colliding with a portion 100a of the ground member 132 exposed from the case 131Y at a portion other than the bifurcated portion 1322Y and the leg portion 1321Y. By doing so, it is possible to prevent the portion exposed from the case 131Y from colliding with the predetermined portion 100a and to prevent the portion from being damaged. Can be secured.

  In the embodiment described above, the case 131Y constituting the inlay portion 13Y is described as an example provided with the key portion 1312Y. However, even if the key portion 1312Y is not provided. Well, in the embodiment described above, the planetary speed reducer has been described as an example in which the output shaft is a rotating shaft that gives a rotational driving force to the photosensitive member, but the rotating shaft that gives the rotational driving force to the rotated body. However, the present invention is not limited to this as long as it is the output shaft of the rotary drive machine, and a rotary drive machine other than the rotating body other than the photoconductor and the planetary speed reducer may be used.

1 is a schematic configuration diagram of an embodiment of an image forming apparatus of the present invention including an embodiment of a rotational drive unit of the present invention. FIG. 4 is an external perspective view of a photoreceptor roll and a rotation drive unit that rotates the photoreceptor roll. FIG. 3 is an external perspective view of the rotary drive unit shown in FIG. 2. It is an external appearance perspective view from the downward direction of the rotation drive unit for each color. It is sectional drawing of the rotational drive unit for Y color. It is a figure which shows the FF cross section shown in FIG. 5 of an inlay part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printer 1a Case 100a Predetermined part 101a Opening 1011a Notch part 1Y, 1M, 1C, 1K Image formation part 10Y, 10M, 10C, 10K Rotation drive unit 11Y, 11M, 11C, 11K Photoconductor roll 12Y, 12M, 12C, 12K Planetary reducer 121Y, 121M, 121C, 121K Case 1211Y, 1211M, 1211C, 1211K Mounting portion 122Y, 122M, 122C, 122K
13Y, 13M, 13C, 13K Inlay part 131Y, 131M, 131C, 131K Case 1311Y, 1311M, 1311C, 1311K Protruding part 1312Y, 1312M, 1312C, 1312K Key part 1313Y, 1313M, 1313C, 1313K Notch part 132Y, 132M, 132C, 132K Ground member 1321Y, 1321M, 1321C, 1321K Legs 1322Y, 1322M, 1322C, 1322K Bifurcated portion 133Y, 133M, 133C, 133K Screws 134Y, 134M, 134C, 134K Bearings 14Y, 14M, 14C, 14K Photosensitive shafts 15Y, 15M , 15C, 15K coupling 151Y, 151M, 151C, 151K pin

Claims (3)

In the rotational drive unit that rotationally drives the rotating object,
A drive source that generates rotational driving force;
A rotating shaft connected to the rotation center of the rotated body that transmits the rotational driving force generated by the drive source to the rotated body;
A support member that rotatably supports the rotating shaft;
A front portion that is inserted from a predetermined direction into a mounting hole provided in a frame disposed between the drive source and the rotated body, and is located on the front side in the predetermined direction with respect to the mounting hole; A housing having a rear portion located on the rear side in a predetermined direction, the rotation shaft penetrating in the predetermined direction, and housing the support member therein,
The housing is attached to the housing, has a leg portion that is in contact with the rotating shaft inside the housing, and that extends from the rear portion of the housing to the outside of the housing on the rear side in the predetermined direction from the frame. A rotary drive unit comprising an earth member. An electrostatic latent image is formed on the rotating image carrier, and the electrostatic latent image is developed with toner to obtain a toner image on the image carrier. The toner image is finally transferred onto a recording medium and In an image forming apparatus for forming an image composed of a toner image fixed on the recording medium by fixing,
A frame disposed between the drive source and the image carrier and having a predetermined mounting hole;
A rotational drive unit that rotationally drives the image carrier,
The rotational drive unit is
A drive source that generates rotational driving force;
A rotation shaft connected to the rotation center of the image carrier, which transmits the rotational driving force generated by the drive source to the image carrier;
A support member that rotatably supports the rotating shaft;
A front portion that is inserted from a predetermined direction into a mounting hole provided in a frame disposed between the drive source and the image carrier, and is located on the front side in the predetermined direction with respect to the mounting hole; A housing having a rear portion located on the rear side in a predetermined direction, the rotation shaft penetrating in the predetermined direction, and housing the support member therein,
The housing is attached to the housing, has a leg portion that is in contact with the rotating shaft inside the housing, and that extends from the rear portion of the housing to the outside of the housing on the rear side in the predetermined direction from the frame. An image forming apparatus comprising an earth member. The housing has a key extending in the predetermined direction on an outer periphery;
The image forming apparatus according to claim 2, wherein the frame has a key hole through which the key is inserted when the housing is inserted into the mounting hole from a predetermined direction.

Images