JP2003066769A - Photoreceptor rotation transmission mechanism, image forming apparatus, and rotation transmission mechanism - Google Patents

Abstract

[PROBLEMS] To effectively prevent rotation unevenness of a photoconductor without complicated and large-sized expensive sensors and structures. SOLUTION: A photoconductor drive gear 2 made of resin is engaged with a pinion 37 on a drive source side. The cylindrical portion 16 of the gear holding member 3 is pressed into the shaft hole 6 of the photoconductor driving gear 2,
The cylindrical portion 16 is fitted to the photosensitive member drive shaft 18 so as to be movable in the radial direction. The pair of centering plates 4 and 5 are respectively fixed to the side surfaces of the gear holding member 3, and the reference holes 25 of the pair of centering plates 4 and 5 are fitted to the photoconductor drive shaft 18. A pair of centering plates 4 and 5
Is fixed to the gear holding member 3 after the position of the gear holding member 3 fitted to the photoconductor drive gear 2 is adjusted in the radial direction with respect to the axis of the reference hole 25. The photoconductor drive gear 2 and the centering plates 4 and 5 are prevented from rotating by a first drive pin 15, and the gear holding member 3 and the photoconductor drive shaft 18 are prevented from rotating by a second drive pin 21.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is interposed between a photoconductor used in an image forming apparatus such as a copying machine, a printer and a facsimile and a drive source, and transmits the power of the drive source to the photoconductor. The present invention relates to a rotation transmission mechanism of a photoconductor and an image forming apparatus including the rotation transmission mechanism of the photoconductor. Further, the present invention relates to a rotation transmission mechanism that is interposed between the rotated body and the drive source and transmits the power of the drive source to the rotated body.

[0001]

2. Description of the Related Art An electrophotographic image forming apparatus (for example,
In photocopiers, printers, and facsimiles, a photoconductor is provided as one of the members that largely determines the quality of image quality, and its rotation is driven by a rotation transmission mechanism including a gear (photoconductor drive gear). Be seen.

To give an example of such a rotation transmission mechanism, a photoconductor drive gear is fixed to a photoconductor drive shaft integral with the photoconductor. An output gear provided on the output shaft of the photoconductor driving motor as a drive source is meshed with the photoconductor driving gear. Therefore, the power from the photoconductor drive motor is transmitted to the photoconductor via the output gear, the photoconductor drive gear, and the photoconductor drive shaft. As described above, the rotation transmission mechanism of the photoconductor sets the number of gears between the photoconductor drive motor and the photoconductor to one to eliminate the uneven rotation of the photoconductor as much as possible.

Further, in recent years, in order to reduce the operating noise of the image forming apparatus and to reduce the weight thereof, the rotation transmitting mechanism of the photoconductor should use a photoconductor drive gear made of resin and formed by injection molding. Has become.

By the way, as described above, the rotation transmission mechanism of the photoconductor is configured so that the photoconductor drive gear, the photoconductor drive shaft, and the photoconductor rotate integrally. When the rotation unevenness occurs, the rotation unevenness is directly transmitted to the photoconductor. When the rotation unevenness occurs on the photoconductor, the toner image finally formed on the sheet material (for example, a transfer material such as paper or a transparent film) is misaligned and appears. Particularly, when the image forming apparatus is a four-color full-color image, toner images of respective colors (for example, magenta, cyan, yellow, and black) are superposed on the sheet material, so that the toner image is misaligned. Appears as a noticeable deterioration in image quality.

In order to prevent the uneven rotation of the photoconductor which causes the positional deviation and the color deviation of the toner image as described above,
It is effective to increase the precision of the resin-made photoconductor drive gear formed by injection molding and improve the rotation precision of the photoconductor drive gear with respect to the axis of the photoconductor drive shaft (first example). .

Further, in order to prevent the uneven rotation of the photoconductor which causes the positional shift and color shift of the toner image, the rotation of the photoconductor is detected by a sensor, and the detection result is fed back to the control device. It is effective that the control device controls the rotation of the photoconductor to smooth the rotation of the photoconductor (second example).

[0007]

However, in the above-mentioned first example, there is a limit to the high precision of the photoconductor drive gear due to the influence of the precision of the mold used for injection molding and the shrinkage of the resin. In addition, in the conventional example in which the photoconductor drive gear is directly fitted to the photoconductor drive shaft, the molding error of the shaft hole of the photoconductor drive gear and the molding error of the tooth portion are accumulated. It is difficult to prevent uneven rotation of the photoconductor to the extent that the demand can be met.

Further, in the above-mentioned second example, it is necessary to dispose a sensor and a control device, the structure of the rotation transmission mechanism is complicated and expensive, and the rotation control of the photoconductor becomes complicated. There is.

The above-mentioned problems occur not only when the photoconductor is a drum-shaped photoconductor drum but also when it is a belt-shaped photoconductor belt. Further, not limited to the rotation transmission mechanism used in the image forming apparatus,
This is also a problem that occurs in a rotation transmission mechanism that rotates a rotating body in which rotation unevenness is a problem in general precision machines.

Therefore, according to the present invention, when a resin gear is used as the photoconductor driving gear, uneven rotation of the photoconductor can be effectively prevented without causing an expensive sensor and a complicated structure and an increase in size. It is an object of the present invention to provide a rotation transmitting mechanism of a photoconductor capable of performing the above and an image forming apparatus including the rotation transmitting mechanism of the photoconductor. Further, the present invention is not limited to a photoconductor, and provides a rotation transmission mechanism capable of effectively preventing uneven rotation of a rotated body such as a precision machine or an automobile part with a simple structure. To aim.

[0011]

According to a first aspect of the present invention, there is provided a photoconductor rotation transmission mechanism for transmitting power from a drive source to a photoconductor drive shaft that rotationally drives the photoconductor. The rotation transmission mechanism of the photoconductor has a resin photoconductor drive gear that meshes with the gear on the drive source side, and a cylindrical portion that is movably fitted to the photoconductor drive shaft in the radial direction, A gear holding member whose outer peripheral side is press-fitted into a shaft hole of a rotation center portion of the photoconductor drive gear, and a reference fixed to both side surfaces of the gear holding member and fitted to the photoconductor drive shaft. And a pair of centering plates having holes. The pair of centering plates has a gear holding member integrated with the photoconductor drive gear by press-fitting the cylindrical portion into the shaft hole of the photoconductor drive gear with respect to the axis of the reference hole. After the position is adjusted in the radial direction, it is fixed to the gear holding member. Further, the photoconductor drive gear is prevented from rotating by the first rotation preventing means so as to be integrally rotatable with respect to at least one of the gear holding member and the pair of centering plates. At least one of the pair of centering plates is fixed to the photoconductor drive shaft by a second rotation preventing means so as to be integrally rotatable.

According to a second aspect of the present invention, in the rotation transmission mechanism of the photoconductor according to the first aspect, the gear holding member is
It is characterized in that a substantially disk-shaped mass portion located on one side surface side of the photoreceptor driving gear is integrally formed with the cylindrical portion.

A third aspect of the present invention relates to a rotation transmission mechanism for transmitting power from a drive source to a drive shaft that rotationally drives a rotating body. The rotation transmission mechanism has a resin drive gear that meshes with the drive source side gear, and a cylindrical portion that is movably fitted to the drive shaft in the radial direction. A gear holding member press-fitted into a shaft hole of a rotation center of the drive gear, and a pair of centering plates each having a reference hole fixed to both side surfaces of the gear holding member and fitted into the drive shaft. I have it. In the pair of centering plates, the gear holding member integrated with the drive gear by pressing the cylindrical portion into the shaft hole of the drive gear is positioned in the radial direction with respect to the shaft center of the reference hole. After the adjustment, it is fixed to the gear holding member. Further, the drive gear is locked by at least one of the gear holding member and the pair of centering plates so as to be integrally rotatable by a first locking means. Further, at least one of the gear holding member and the pair of centering plates is attached to the drive shaft as a second portion.
The rotation preventing means prevents the rotation so that they can be integrally rotated.

According to a fourth aspect of the present invention, in the rotation transmission mechanism according to the third aspect of the present invention, the gear holding member has a substantially disk-shaped mass portion located on one side surface side of the drive gear and the cylindrical portion. It is characterized in that it is formed integrally with.

A fifth aspect of the present invention forms a toner image on the surface of the photoconductor rotation transmission mechanism according to the first or second aspect of the present invention and the photoconductor rotated by the rotation transmission mechanism of the photoconductor. Image forming means, transfer means for transferring the toner image on the surface of the photoreceptor formed by the image forming means to a transfer material, and fixing means for fixing the toner image transferred by the transfer means on the transfer material. The present invention relates to an image forming apparatus characterized by the above.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

[First Embodiment] (Photosensitive Member Rotation Transmission Mechanism) FIG. 1 is a vertical sectional view showing a usage state of the photosensitive member rotation transmission mechanism 1 according to the first embodiment of the present invention. It is shown. FIG. 2 is an exploded perspective view of the rotation transmission mechanism 1 of the photoconductor.

As shown in these drawings, the rotation transmission mechanism 1 of the photoconductor (hereinafter, simply referred to as "rotation transmission mechanism") includes a photoconductor drive gear 2 and a gear holding member for holding the photoconductor drive gear 2. 3 and a pair of centering plates 4 and 5 arranged so as to sandwich the photoconductor drive gear 2 and the gear holding member 3.

The photosensitive member drive gear 2 is, for example, a resin helical gear injection-molded using a resin material such as polyacetal or fluorine-containing polycarbonate. As shown in FIGS. 1 to 3, the photoconductor drive gear 2 is formed on a cylindrical shaft support portion 7 having a shaft hole 6 formed in the center of rotation, and on the outer peripheral side of the shaft support portion 7. A substantially disk-shaped web 8
And a substantially cylindrical tooth portion 10 formed on the outer peripheral side of the web 8. Then, the photoconductor drive gear 2
First circumferential ribs 11 are formed on both side surfaces of the web 8 of the shaft 8 concentrically with the above-mentioned shaft supporting portion 7. Between the first circumferential rib 11 and the tooth portion 10, the above-mentioned shaft supporting portion 7 is supported. Second concentric with part 7
Circumferential ribs 12 are formed, and further, a plurality of inner radial ribs 13 that radially connect the shaft support portion 7 and the first circumferential rib 11, a first circumferential rib 11 and a second circumferential rib 11. A plurality of outer radial ribs 14 are formed to radially connect the circumferential ribs 12 of FIG. As shown in FIG. 3, a first drive pin (first detent means) 15 of a centering plate 5, which will be described later, comes into contact with the outer radial rib 14 of the photoconductor drive gear 2, and the centering plate 5 rotates integrally with the photoconductor drive gear 2 in the rotation direction (R) of the photoconductor drive gear 2. Further, the photosensitive member drive gear 2 is formed in a bilaterally symmetrical shape with the web 8 as the center in FIG.

The gear holding member 3 is formed by die casting using a metal such as a zinc alloy or an aluminum alloy. This gear holding member 3 is shown in FIGS.
As shown in FIGS. 4 and 5, the shaft hole 6 of the photoconductor drive gear 2 is
The cylindrical portion 16 press-fitted into the cylindrical portion 16 and the substantially disk-shaped mass portion 1 integrally formed on the outer peripheral side of the cylindrical portion 16 and on one side surface side.
7 is provided. The mass portion 17 of the gear holding member 3 is provided on one side surface side of the photoconductor drive gear 2 (the shaft support portion 7, the first circumferential rib 11, the second circumferential rib 12,
The inner radial rib 13 and the outer radial rib 14 are in contact with the right end faces in FIG. 1). Further, the gear holding member 3 is formed with a shaft receiving hole 20 at the center of rotation thereof, which is fitted into the photoconductor drive shaft 18 with a gap.
In the shaft receiving hole 20 of the gear holding member 3, a pin groove 22 that engages with the second drive pin (second detent means) of the photoconductor drive shaft 18 corresponds to the second drive pin 21. A pair is formed at the target position in the circumferential direction. Furthermore,
The gear holding member 3 is provided with a plurality of screw receiving holes 23 penetrating the cylindrical portion 16 from one side surface side to the other side surface side in the circumferential direction. It should be noted that shaft portions of screws 24 for fixing the centering plates 4 and 5 on both side surfaces of the gear holding member 3 are inserted into the screw receiving holes 23 of the gear holding member 3 with a gap. There is.

The pair of centering plates 4 and 5 are, for example,
It is formed into a disc shape by press working using a metal plate such as a rolled steel plate. This pair of centering plates 4, 5
One of the centering plates 4 arranged on the right side of FIG. 1 is fitted to the photosensitive member drive shaft 18 with high accuracy at the center of rotation thereof, as shown in FIGS. 1, 2, 6 and 7. A reference hole 25 to be fitted is formed. This one centering plate 4
The reference hole 25 is processed in such an accuracy range that it is easily press-fitted into the photoconductor drive shaft 18 or fitted into the photoconductor drive shaft 18 with a very small gap. In the reference hole 25 of the one centering plate 4, a pair of pin insertion grooves 26 through which the second drive pin 21 of the photoconductor drive shaft 18 can pass is formed at a target position in the circumferential direction.
Further, a screw through hole 27 corresponding to the screw receiving hole 23 of the gear holding member 3 is formed in the one centering plate 4, and the shaft portion of the screw 24 is inserted into the screw through hole 27. It has become so. The reference holes 25 of the pair of centering plates 4 and 5 are processed by precision press working or grinding, and compared with the accuracy of the shaft hole 6 of the resin-made photoconductor drive gear 2 injection-molded. It is formed with high precision.

FIG. 1 of the pair of centering plates 4 and 5.
The other centering plate 5 arranged on the left side of FIG.
As shown in FIGS. 2, 8 and 9, similarly to the above-described one centering plate 4, a reference hole 25 that is fitted with high precision to the photoconductor drive shaft 18 is formed at the center of rotation. . The reference hole 25 of the other centering plate 5 is, like the reference hole 25 of the one centering plate 4 described above, easily press-fitted into the photoconductor drive shaft 18 or is extremely small in the photoconductor drive shaft 18. It is processed within the accuracy range so that it fits with a small gap. The other centering plate 5 has a screw hole 28 that is screwed into the screw 24 at a position corresponding to the screw receiving hole 23 of the gear holding member 3.
The other centering plate 5 has a pair of pin press-fitting holes 30 formed at circumferentially symmetrical positions on the outer side in the radial direction, and each of the pin press-fitting holes 30 has a first drive pin (first drive pin).
(Rotation preventing means) 15 is press-fitted and fixed (see FIG. 8 etc.). The first drive pin 15 fixed to the other centering plate 5 includes the first circumferential rib 11, the second circumferential rib 12, and the pair of outer diameters adjacent to each other of the photoconductor drive gear 2 described above. It is housed in a space partitioned by the direction ribs 14, 14 and contacts the outer radial rib 14 when the photoconductor drive gear 2 rotates (see FIG. 3 and the like), and the photoconductor drive gear 2 and a gear holding member. 3 and the pair of centering plates 4 and 5 can be integrally rotated.

Now, the procedure for assembling the rotation transmission mechanism 1 will be described. First, the cylindrical portion 16 of the gear holding member 3 is press-fitted into the shaft hole 6 of the photoconductor driving gear 2, and the mass portion 17 of the gear holding member 3 is brought into close contact with one side surface side of the photoconductor driving gear 2. Next, one centering plate 4 is arranged on one side surface side of the gear holding member 3, the other centering plate 5 is arranged on the other side surface side of the gear holding member 3, and the gear holding member 3 is set with the screw 24. And the pair of centering plates 4 and 5 are temporarily fixed. The rotation transmission mechanism 1 temporarily fixed by the screw 24 is arranged so that the gear holding member 3 can be displaced in the radial direction (vertical direction in FIG. 1) with respect to the pair of centering plates 4 and 5. Has become.

Then, this temporarily fixed rotation transmission mechanism 1
Is fitted to a reference shaft (not shown) for centering, which is formed in the same size as the photosensitive member drive shaft 18. That is, the reference hole 25 of the pair of centering plates 4 and 5 and the shaft receiving hole 20 of the gear holding member 3 are fitted to the reference shaft. The reference axis is
The gear holding member 3 is displaced with respect to the pair of centering plates 4 and 5 so that the shaft center (rotation center) of the pair of centering plates 4 and 5 and the shaft center (rotation center) of the photoconductor drive gear 2 are aligned ( Centering) to reduce the runout of the addendum circle of the photoconductor drive gear 2 with respect to the axis of the reference hole 25 of the pair of centering plates 4 and 5 when rotating.
It also functions as an assembly jig for the rotation transmission mechanism 1.

After the gear holding member 3 and the pair of centering plates 4 and 5 are temporarily fixed with an adhesive in a state where the runout of the addendum circle of the photosensitive member drive gear 2 is within a desired accuracy range, The gear holding member 3 and the pair of centering plates 4 and 5 are fastened and fixed with screws.

The rotation transmission mechanism 1 thus assembled is fitted to the photoconductor drive shaft 18. At this time, the rotation transmission mechanism 1 is fitted into the photoconductor drive shaft 18 through the reference hole 25 of the one centering plate 4, and the second drive pin 21 of the photoconductor drive shaft 18 is set to the one centering plate 4. The pin holding groove 26 of the gear holding member 3 is engaged with the pin holding groove 26 of the gear holding member 3. Then, the rotation transmission mechanism 1 is moved on the photoconductor drive shaft 18 until it comes into contact with the shaft retaining ring 31 of the photoconductor drive shaft 2.

The photosensitive member drive shaft 18 to which the rotation transmission mechanism 1 is attached is rotatably supported by bearings 34 and 35 attached to the frame side of the image forming apparatus. The photoconductor drive gear 2 of the rotation transmission mechanism 1 is meshed with a pinion (gear on the drive source side) 37 attached to the output shaft of the photoconductor drive motor 36 as a drive source (FIGS. 11 and 12). reference). The rotation transmission mechanism 1
The position on the photoconductor drive shaft 18 is regulated by the shaft retaining ring 31 and the bearing 35 (see FIG. 1, etc.).

Next, how the rotation of the photoconductor drive motor 36 is transmitted to the photoconductor drive shaft 18 by the rotation transmission mechanism 1 will be described. That is, the rotation of the photoconductor drive motor 36 is transmitted to the photoconductor drive gear 2 via the pinion 37 attached to the output shaft, and the other centering is performed from the photoconductor drive gear 2 via the first drive pin 15. It is transmitted to the plate 5, is transmitted from the other centering plate 5 to the gear holding member 3 via the screw 24, and is transmitted from the gear holding member 3 to the photoconductor drive shaft 18 via the second drive pin 21.
To be transmitted to. The photosensitive member drive shaft 1
8, a photosensitive drum 86 as a photosensitive member is attached so as to be integrally rotatable as shown in FIG. 11, or a driving roller 90 for a photosensitive belt 88 is attached as shown in FIG. ing.

In the rotation transmitting mechanism 1 of the present embodiment configured as described above, the shift of the shaft center of the addendum circle of the photoconductor drive gear 2 with respect to the shaft center of the centering plates 4 and 5 causes the gear holding member. Since it is adjusted by shifting 3 with respect to the centering plates 4 and 5, compared with the conventional first example in which the injection-molded resin photoconductor drive gear is directly fitted to the photoconductor drive shaft, The amount of eccentricity of the addendum circle of the photoconductor drive gear 2 with respect to the photoconductor drive shaft 18 can be reduced, and uneven rotation of the addendum circle of the photoconductor drive gear 2 can be suppressed. Moreover, in the rotation transmission mechanism 1 of the present embodiment, the centering plates 4 and 5 fitted to the photoconductor drive shaft 2 are made of metal, and the dimensional accuracy of the reference holes 25 of the centering plates 4 and 5 is improved. Since it is possible to achieve higher precision than the dimensional precision of the shaft hole of the injection-molded photoreceptor drive gear of the first conventional example,
In combination with the above effects, the amount of eccentricity of the tip circle of the photoconductor drive gear 2 with respect to the photoconductor drive shaft 18 is further reduced as compared with the conventional photoconductor drive gear of the first example. Therefore, with the rotation transmission mechanism 1 according to the present embodiment as described above, it is possible to make the rotation unevenness of the photoconductor mounted on the photoconductor drive shaft 18 smaller than in the first example of the related art, and it is smooth and high. Accurate rotation transmission is possible.

Further, the rotation transmission mechanism 1 of this embodiment is
Since a sensor or a control device for controlling the rotation of the photoconductor drive shaft 18 is not used, as compared with the conventional second example,
The configuration is simple and inexpensive.

Further, the rotation transmission mechanism 1 of this embodiment is
Since the gear holding member 3 includes the mass portion 17 and the gear holding member 3 functions as a flywheel, the photoconductor drive shaft 18
The inertia becomes large, the fluctuation of the rotational angular velocity of the photoconductor drive shaft 18 becomes small, and the photoconductor drive shaft 18 and the photoconductor mounted on the photoconductor drive shaft 18 can be smoothly rotated.

Further, the rotation transmission mechanism 1 of this embodiment is
When fixing the pair of centering plates 4 and 5 and the gear holding member 3, the photosensitive drum driving gear 2 made of resin is not directly tightened by the screw 24, so that the photosensitive drum driving gear 2 creeps. It is possible to prevent the deformation, and it is possible to prevent the shape accuracy of the photoconductor drive gear 2 from being lowered.

(Image Forming Apparatus) FIG. 10 shows an image forming apparatus 7 to which the rotation transmission mechanism 1 according to the above-described embodiment is applied.
It is a schematic block diagram of 0.

In the image forming apparatus 70 shown in this figure, a sheet material (transfer material) 72 sent from a paper feed roller 71a of a paper feed section 71 is transferred to a photosensitive member 74 and a transfer roller (transfer roller) by a transfer roller 73a of a sheet transfer section 73. Transfer means) 75, and the sheet material 72 is sent between the fixing roller 77a and the pressure roller 77b of the fixing means 76, and the sheet material 7
The four-color toner images formed on the two surfaces are fixed to form a color image, and the sheet material 72 after the fixing operation is discharged onto the discharge tray 80 by the discharge roller pair 78.

The photosensitive member 74 is adapted to be rotated in the clockwise direction (arrow direction) in FIG. 10, and has a cleaning unit 81, a discharge lamp 82, a charger 83, an exposure unit 84, and a color developing unit around it. Unit 85 (85a,
An image forming unit 79 including 85b, 85c, 85d) is provided. In this photoconductor 74, for example, as shown in FIG. 11, the photoconductor drive shaft 18 fixed to the center of rotation of the photoconductor drum 86 is connected to the photoconductor drive motor 36 as a drive source by the rotation transmission mechanism 1. Four color images of yellow (Y), magenta (M), cyan (C), and black (BK) of the color developing unit 85 are connected to each other and are superimposed on each other.

In the image forming apparatus 70 having such a structure, since the rotation of the photoconductor driving motor 36 is smoothly and accurately transmitted to the photoconductor 74 via the rotation transmission mechanism 1, the photoconductor 74 rotates. The unevenness and the fluctuation of the rotational angular velocity are suppressed, the deviation of the toner image of each color formed on the photoconductor 74 is suppressed, and a clear color image can be formed.

In the above-described embodiment, the photoconductor drum 86 is illustrated as the photoconductor 74, but the present invention is not limited to this, and a photoconductor belt may be used as the photoconductor 74. That is, as shown in FIG. 12, the rotation transmission mechanism 1 is arranged on the drive shaft of the drive roller 90 of the photoreceptor belt 88, and the photoreceptor drive gear 36 of the rotation transmission mechanism 1 is provided with the photoreceptor drive motor 36. Of the pinion 37, the rotation of the photoconductor drive motor 36 is transmitted to the drive roller 90 via the pinion 37 and the rotation transmission mechanism 1, and the photoconductor belt 88 is rotated smoothly and with high precision. Good. Even with such a configuration, the same effect as the above can be obtained.

[Second Embodiment] FIG. 13 is a vertical sectional view of a rotation transmission mechanism 1 according to a second embodiment of the present invention. As shown in this figure, in the rotation transmission mechanism 1 according to the present embodiment, the first drive pin 15 is fixed to the side of the mass portion 17 of the gear holding member 3 facing the photoconductor drive gear 2. There is. The first drive pin 15 of the gear holding member 3 contacts the outer radial rib 14 of the photoconductor drive gear 2.

The rotation transmission mechanism 1 according to this embodiment is
The rotation of the photoconductor drive motor 36 is transmitted to the photoconductor drive gear 2 via the pinion 37, the rotation of the photoconductor drive gear 2 is transmitted to the gear holding member 3 via the first drive pin 15, and the gear holding member The rotation of 3 is transmitted to the photoconductor drive shaft 18 via the second drive pin 21. With such a configuration, the same effect as that of the above-described embodiment can be obtained.

[Third Embodiment] FIG. 14 is a vertical sectional view of a rotation transmitting mechanism 1 according to a third embodiment of the present invention. As shown in this figure, in the rotation transmission mechanism 1 according to the present embodiment, the gear holding member 3 has a shape in which the mass portion 17 of the gear holding member 3 of the first embodiment is cut off. One centering plate 4 contacts one side surface of the drive gear 2. The rotation transmission mechanism 1 having such a configuration is similar to the first embodiment,
The rotation unevenness of the photoconductor drive gear 2 can be reduced, high-precision rotation transmission can be performed, and the rotation unevenness of the photoconductor mounted on the photoconductor drive shaft 18 can be reduced. It is possible to form an image with high accuracy without causing a problem.

[Fourth Embodiment] FIG. 15 is a vertical sectional view of a rotation transmission mechanism 1 according to a fourth embodiment of the present invention. As shown in this figure, the rotation transmission mechanism 1 according to the present embodiment includes the other centering plate 5 of FIG.
The first drive pin 15 fixed to the
The first drive pin 15 is brought into contact with the outer radial rib 14 of the photoconductor drive gear 2.
In this embodiment having such a configuration, the same operation and effect as those of the above-described third embodiment can be obtained.

[Fifth Embodiment] FIG. 16 is a vertical sectional view of a rotation transmission mechanism 1 according to a fifth embodiment of the present invention. In the rotation transmission mechanism 1 of the present embodiment shown in this figure, the first drive pin 15 of the centering plate 5 is engaged with the hole 38 formed in the web 8 to move the first drive pin 15 from the photoconductor drive gear 2. The rotation is transmitted to the other centering plate 5 via the. The rotation transmission mechanism 1 of the present embodiment having such a configuration can exhibit the same operation and effect as those of the first embodiment.

[Sixth Embodiment] FIG. 17 is a vertical sectional view of a rotation transmitting mechanism 1 according to a sixth embodiment of the present invention. 18 to 20 are diagrams of the gear holding member 3 that constitutes the rotation transmission mechanism 1 according to the present embodiment. Of these, FIG. 18 is an external perspective view of the gear holding member 3, and FIG. 19 is a vertical cross-sectional view of the gear holding member 3 (see FIG. 2).
It is sectional drawing which cut | disconnects and shows along the KK line of 0 (a). Further, FIG. 20 (a) shows the gear holding member 3 as shown in G of FIG.
20B is a left side view when viewed from the direction, and FIG. 20B is a right side view when the gear holding member 3 is viewed from the H direction in FIG. 18.

The rotation transmission mechanism 1 according to the present embodiment shown in FIG. 17 is the same as the rotation transmission mechanism 1 of the first embodiment shown in FIG. The arrangement configuration of the second drive pin 21 that prevents rotation with respect to the photoconductor drive shaft 18 is changed. That is,
In the rotation transmission mechanism 1 of the present embodiment, a portion substantially corresponding to the mass portion 17 of the gear holding member 3 of the first embodiment is composed of a plurality of disc-shaped members 40, 41, 42 made of metal, The plurality of disc-shaped members 41 to 42 are arranged between one of the centering plates 4 and the spring member 43 having a substantially corrugated cross section.
Is pressed against the side surface of the photoconductor drive gear 2 to rotate integrally with the photoconductor drive gear 2.

As shown in FIGS. 17 to 20, the gear holding member 3 which constitutes the rotation transmission mechanism 1 of the present embodiment is press-fitted into the shaft hole 6 of the photoconductor drive gear 2 and at the same time the photoconductor drive gear 2 is pressed. Hole 44 of the first disc-shaped member 40 that abuts the side surface of the
And the first cylindrical portion 16a fitted to the shaft hole 4 of the plurality of other disc-shaped members 41 and 42 excluding the first disc-shaped member 40.
5 is formed with the second cylindrical portion 16b fitted to 5,
The second cylindrical portion 16b is formed to have a larger diameter than the first cylindrical portion 16a, and the step rising walls 46 of the first cylindrical portion 16a and the second cylindrical portion 16b form the inner circumference of the first disc-shaped member 40. It is designed to abut the end side surface. Here, when the pair of centering plates 4 and 5 is fastened and fixed to the side surface of the gear holding member 3 with the screw 24, the photoconductor drive gear 2 is sandwiched between the centering plate 5 and the first disc-shaped member 40. To be done. Further, the gear holding member 3 has the first shaft receiving hole 20 at the center of rotation thereof.
a and the second shaft receiving hole 20b are formed, and the hole diameter of the second shaft receiving hole 20b is sufficiently larger than that of the first shaft receiving hole 20a located on the photoconductor drive shaft insertion side. As a result, the overall weight is reduced and the component cost is reduced. A pair of pin grooves 22 is formed in the first shaft receiving hole 20a so as to correspond to the second drive pin 21 of the photoconductor drive shaft 18. The first shaft receiving hole 20a is
By moving the gear holding member 3 in the radial direction of the photoconductor drive shaft 18, the photoconductor drive gear 2 with respect to the axis of the photoconductor drive shaft 18 is moved.
The dimensional accuracy is adjusted so that the misalignment can be adjusted. Further, the second shaft receiving hole 20b is formed with a diameter as large as possible so that the thickness for forming the screw receiving hole 23 can be secured.

In the rotation transmission mechanism 1 of the present embodiment having such a configuration, the rotation of the photoconductor drive motor 36 is performed by rotating the photoconductor drive gear 2 through the pinion 37 attached to the output shaft.
Is transmitted to the other centering plate 5 from the outer radial rib 14 of the photoconductor drive gear 2 via the first drive pin 15 and from the other centering plate 5 via the screw 24 to the gear holding member 3 To the second from the gear holding member 3.
It is adapted to be transmitted to the photoconductor drive shaft 18 via the drive pin 21.

The rotation transmission mechanism 1 as described above is
It goes without saying that the same effects as those of the above-described first embodiment can be obtained, and the disk-shaped members 40 and 4 that can be pressed.
By using 1, 42 as the mass part, it is possible to reduce the manufacturing cost, and by forming the second shaft receiving hole 20b having a large diameter in the gear holding member 3, it is possible to reduce the weight. At the same time, the cost of parts can be reduced.
Note that, as can be understood by comparing FIG. 1 and FIG. 17, the rotation transmission mechanism 1 can appropriately change the outer shape according to other adjacent members not shown.

[Other Modifications] In each of the above embodiments, the first drive pin 15 is illustrated as the first rotation stopping means, but the invention is not limited to this, and the centering plates 4 and 5 are not limited thereto. It is only necessary that at least one of them and the photoconductor drive gear 2 be integrally rotated, or that the gear holding member 3 and the photoconductor drive gear 2 be integrally rotated, and the form thereof is not limited.

In each of the above embodiments, the second
The second drive pin 21 has been exemplified as the rotation stopping means of the
The present invention is not limited to this, as long as the gear holding member 3 and the photoconductor drive shaft 18 can be integrally rotated. For example, the gear holding member 3 and the photoconductor drive shaft 18 can be engaged by spline fitting or serration fitting. Alternatively, the gear holding member 3 and the photoconductor drive shaft 18 may be integrally rotated with a key.

Further, in each of the above-described embodiments, the pair of centering plates 4 and 5 and the gear holding member 3 are screwed together.
However, the present invention is not limited to this, and the pair of centering plates 4 and 5 and the gear holding member 3 may be integrated by spot welding or the like.

Further, in each of the above-described embodiments, the gear holding member 3 and the photosensitive member drive shaft 18 are configured to be prevented from rotating by the second drive pin 21, but the invention is not limited to this.
Either one of the pair of centering plates 4 and 5 and the photoconductor drive shaft 18 may be prevented from rotating by the second rotation preventing means.

In the above-described embodiment, the rotation transmission mechanism 1 according to the present invention is provided between the photoconductor drive motor 36 and the photoconductor drive shaft 18 so as to eliminate uneven rotation of the photoconductor 74. . The problem of such rotation unevenness is not limited to the case where the rotated body is the photoconductor 74, but also occurs when the rotated body is a general body. The above-described rotation transmission mechanism 1 according to the present invention can be applied as a rotation transmission mechanism for general precision devices, automobile parts, etc. without being limited to the image forming apparatus 70 while keeping the basic configuration almost the same. it can. That is, the photosensitive member drive gear 2 and the photosensitive member drive shaft 1 in FIG.
By replacing 8 with general drive gears and drive shafts, respectively, a rotation transmission mechanism applicable to a wide range of technical fields can be constructed. That is, it is possible to eliminate uneven rotation of the rotated body.

[0053]

According to the rotation transmitting mechanism of the photoconductor of the present invention, the shift of the axis of the addendum circle of the photoconductor driving gear with respect to the axis of the centering plate is fitted to the photoconductor driving gear. Is adjusted by displacing the photoconductor drive gear with respect to the centering plate. Therefore, as compared with the conventional first example in which the photoconductor drive gear made of injection molded resin is directly fitted to the photoconductor drive shaft, The amount of eccentricity of the tooth tip circle with respect to the photoconductor drive shaft can be reduced, and uneven rotation of the tooth tip circle of the photoconductor drive gear can be suppressed. Moreover, since the rotation transmitting mechanism of the photoconductor of the present invention does not use the sensor or the rotation control device, the structure can be simplified and the cost can be reduced as compared with the second conventional example.

Further, since the image forming apparatus of the present invention is provided with the above-described photoconductor rotation transmission mechanism, uneven rotation of the photoconductor is suppressed, color misregistration and image misregistration are suppressed, and a high quality image is obtained. Can be formed.

Further, in the rotation transmitting mechanism of the present invention, the shift of the shaft center of the addendum circle of the drive gear with respect to the shaft center of the centering plate causes the gear holding member fitted to the drive gear to move with respect to the centering plate. Since it is adjusted by shifting, the amount of eccentricity of the addendum circle of the drive gear with respect to the drive shaft can be reduced, and uneven rotation of the addendum circle of the drive gear can be suppressed. Moreover, since the rotation transmission mechanism of the present invention does not use the sensor or the rotation control device, the structure can be simplified and the cost can be reduced as compared with the conventional second example.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a usage state of a rotation transmission mechanism according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the rotation transmission mechanism according to the first embodiment of the present invention.

3 is a side view of the photoconductor drive gear of the rotation transmission mechanism of FIG. 1 as viewed from the left side of FIG.

FIG. 4 is a vertical cross-sectional view of a gear holding member (cross-sectional view cut along the line AA in FIG. 5).

5 is a side view of a gear holding member (a side view seen from the direction B in FIG. 4).

FIG. 6 is a vertical cross-sectional view of one centering plate (C- in FIG. 7).
It is sectional drawing cut and shown along a C line).

FIG. 7 is a side view of one centering plate (a side view seen from the direction D in FIG. 6).

FIG. 8 is a vertical sectional view of the other centering plate (E- in FIG. 9).
It is sectional drawing which cut | disconnects and shows along the E line.

FIG. 9 is a side view of the other centering plate (a side view seen from the F direction in FIG. 8).

FIG. 10 is a diagram showing a schematic configuration of an image forming apparatus provided with a rotation transmission mechanism for a photoconductor of the present invention.

FIG. 11 is a diagram showing a drive mechanism of a photosensitive drum.

FIG. 12 is a diagram showing a drive mechanism of a photosensitive belt.

FIG. 13 is a vertical sectional view of a rotation transmission mechanism according to a second embodiment of the present invention.

FIG. 14 is a vertical cross-sectional view of a rotation transmission mechanism according to a third embodiment of the present invention.

FIG. 15 is a vertical sectional view of a rotation transmission mechanism according to a fourth embodiment of the present invention.

FIG. 16 is a vertical sectional view of a rotation transmission mechanism according to a fifth embodiment of the present invention.

FIG. 17 is a vertical sectional view of a rotation transmitting mechanism according to a sixth embodiment of the present invention.

FIG. 18 is an external perspective view of a gear holding member that constitutes a rotation transmission mechanism according to a sixth embodiment of the present invention.

FIG. 19 is a vertical cross-sectional view (a cross-sectional view cut along the line KK of FIG. 20A) of the gear holding member that constitutes the rotation transmission mechanism according to the sixth embodiment of the present invention. is there.

20 (a) is a left side view of the gear holding member as seen from the G direction in FIG. 18, and FIG. 20 (b) is an H side view in FIG.
It is a right side view of the gear holding member seen from the direction.

[Explanation of symbols]

1 ... Rotation transmission mechanism, 2 ... Photoconductor drive gear, 3 ... Gear holding member, 4, 5 ... Centering plate, 6 ... Shaft hole,
15 ... First drive pin (first detent means), 16 ...
… Cylindrical part, 17 …… Mass part, 18 …… Photosensitive member drive shaft, 2
1 ... Second drive pin (second detent means), 25 ...
Reference hole, 36 ... Motor for driving photoconductor (driving source), 37
...... Pinion (gear on the drive source side), 72 ...... sheet material (transfer material), 74 …… photoconductor, 75 …… transfer roller (transfer means), 76 …… fixing means, 79 …… image forming means

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shoji Wada             5-13-3-3 Nakanocho, Miyakojima-ku, Osaka City, Osaka Prefecture             1009 F-term (reference) 2H035 CA07 CB01 CB06 CG03                 2H071 BA03 BA20 CA02 CA05 DA15                       DA16 DA26                 3J030 AA08 BA01 BC01 BD06 CA01

Claims (5)

[Claims] 1. A photoconductor rotation transmission mechanism that transmits power from a drive source to a photoconductor drive shaft that rotationally drives the photoconductor, the photoconductor drive gear being made of resin and meshing with a gear on the drive source side. A gear holding member that has a cylindrical portion that is movably fitted to the photosensitive member drive shaft in a radial direction, and the outer peripheral side of the cylindrical portion is press-fitted into the shaft hole of the rotation center portion of the photosensitive member drive gear; A pair of centering plates fixed to both side surfaces of the gear holding member and having reference holes fitted into the photoconductor drive shaft, the pair of centering plates being the photoconductor drive gear. The gear holding member integrated with the photoconductor drive gear by press-fitting the cylindrical portion into the shaft hole is fixed in the gear holding member after the position of the gear holding member is adjusted in the radial direction with respect to the axis of the reference hole. The photoconductor drive gear is A first member and at least one of the pair of centering plates so that they can be integrally rotated; and at least one of the gear holding member and the pair of centering plates is the photosensitive member. A rotation transmitting mechanism for a photosensitive member, wherein the rotation is stopped by a second rotation preventing means so as to be integrally rotatable with the body driving shaft. 2. The gear holding member is formed by integrally forming a substantially disk-shaped mass portion located on one side surface side of the photoreceptor driving gear with the cylindrical portion. A rotation transmission mechanism for the photoconductor described. 3. A rotation transmission mechanism that transmits power from a drive source to a drive shaft that rotationally drives a body to be rotated, the drive gear being made of resin, which meshes with a gear on the drive source side, and the drive shaft. A gear holding member that has a cylindrical portion that is movably fitted in the radial direction, and the outer peripheral side of this cylindrical portion is press-fitted into a shaft hole of the rotation center portion of the drive gear, and both side surfaces of the gear holding member. A pair of centering plates that are fixed and have a reference hole that fits into the drive shaft; the pair of centering plates are configured to press the cylindrical portion into a shaft hole of the drive gear to drive the drive unit. A gear holding member integrated with the gear is positionally adjusted in the radial direction with respect to the axial center of the reference hole, and then fixed to the gear holding member, and the drive gear includes the gear holding member and the pair of cores. For at least one of the delivery plates A first rotation stopping means prevents rotation integrally, and at least one of the gear holding member and the pair of centering plates rotates integrally around the drive shaft by a second rotation stopping means. A rotation transmission mechanism characterized by being prevented from rotating. 4. The gear holding member according to claim 3, wherein a substantially disk-shaped mass portion located on one side surface side of the drive gear is integrally formed with the cylindrical portion. Rotation transmission mechanism. 5. A rotation transmission mechanism of the photoconductor according to claim 1 or 2, an image forming unit for forming a toner image on the surface of the photoconductor rotated by the rotation transmission mechanism of the photoconductor, It is characterized by comprising: a transfer unit for transferring the toner image on the surface of the photoconductor formed by the image forming unit to a transfer material; and a fixing unit for fixing the toner image transferred by the transfer unit on the transfer material. Image forming apparatus.