JP2003343602A - Two-way clutch, drive transmission device, and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-way clutch suitable for drive transmission of a image carrier, a drive transmission device using the two-way clutch, and a image forming device using the drive transmission device. <P>SOLUTION: The two-way clutch comprises: a drive shaft 30; a plurality of torque transmission rollers 41 making contact with the other of a light- sensitive element 10 and transmitting rotation drive of the drive shaft 30 to the light-sensitive element 10; a plurality of wedge spaces 42 where the torque transmission member 41 is arranged and formed among a clutch casing 43, a drive element, and the other of a driven element; and a spring 46 to press the torque transmission roller 41 against the wedge side of the wedge space 42 by a given pressure. A direction in which the torque transmission member roller 41 enters the wedge of the wedge spaces 42 is that for connection, and at least one of the wedge spaces 42 has the reverse direction of a wedge against the other wedge space 42. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-way clutch, a drive transmission device using the two-way clutch, and an image forming apparatus such as a copying machine, a printer, a facsimile, or a printing machine using the drive transmission device.

[0002]

2. Description of the Related Art As a photoconductor as an image carrier in an image forming apparatus, an A4 size sheet is used for several 10,000 to several 1
The life of the image forming apparatus reaches the end of its life after the image formation of 0,000 sheets, which is considerably shorter than the life of the main body of the image forming apparatus. Therefore, the photoconductor or the image forming unit including the photoconductor is usually replaced during the life of the main body. Further, it is more naive than the main body against external factors such as adhesion of foreign matter to the surface of the photoconductor and temperature change, and it may be replaced before the end of its life depending on the required image quality level.

Therefore, the photosensitive member or a unit including the photosensitive member is required to have a simple operability so that the user can easily attach and detach the same. Furthermore, since the drive of the photoconductor is driven by the drive provided on the main body side,
The drive connection is reliably transmitted when the photoconductor etc. is attached,
It is necessary to stably rotate the photoconductor.

As a method for satisfying these requirements, as shown in FIG. 14, a cross-shaped pin 81 is planted on a drive shaft 80 on the main body side, and a cross-shaped recess 102 is provided on a flange 101 of a photosensitive member 100. And the photoconductor is attached to the recess 10
2 is fitted into the cross pin 81 and the drive is transmitted. In this method, the photoreceptor can be easily attached and detached, and there is no looseness in the fitting at the initial stage, so that vibration due to backlash or the like does not occur.

However, the drive connection shown in FIG. 14 is difficult in terms of durability, and when the photoconductor is attached and detached several times, looseness occurs in fitting and a striped pattern called banding appears in the output image. There was an occasion. In the case of a color machine, the phenomenon of banding is a cause of color misregistration because four colors of cyan, magenta, yellow, and black are superposed, and the apparent image quality level is significantly reduced.

As a fitting method in which such a problem is unlikely to occur, it has already been proposed to fit by means of tapered serrations as shown in FIG. According to this fitting method, the flange 100 of the photoconductor 100 is provided with the serration concave portion 103 having the serration formed on the concave taper portion, and the drive shaft 80 is provided with the serration convex portion having the serration formed on the convex taper portion. The part 82 is formed. When the photoconductor 100 is inserted into the drive shaft 80, the center of rotation of the photoconductor is easily picked up by the tapered shape, and backlash and the like are eliminated by the engagement of the serrations. This fitting method is
The photoconductor can be stably rotated and has good durability.

[0007]

However, in the above-mentioned fitting method, when the photoconductor 100 is rotated, the photoconductor tries to escape from the serration convex portion 82, so that the photoconductor is pressed against each other by a compression spring or the like. It is necessary to press down in the direction in which is engaged. Of course, a strong force is required when installing this compression spring.
Also, once the photoconductor is attached, it will continue to receive the pressure of the spring, so the fixing force between the serrations will become stronger,
There was a problem that it took a considerable amount of force to remove it.

In view of the above-mentioned conventional problems, the present invention provides a two-way clutch suitable for drive transmission of an image carrier, a drive transmission device using the two-way clutch, and an image forming apparatus using the drive transmission device. That is the issue.

[0009]

In order to solve the above problems, the present invention is fixedly arranged on either one of a driving body driven by a driving source and a driven body driven by the driving body. In a two-way clutch that transmits the drive of the driving body to the driven body by connecting one of the two,
A plurality of torque transmission members that contact the other of the driving body and the driven body to transmit the rotational drive of the driving body to the driven body, and the torque transmission members are arranged, and the clutch housing, the driving body, and the driven body. A plurality of wedge spaces formed between the wedge space and the other, and biasing means for pressing the torque transmission member toward the wedge side of the wedge space with a predetermined pressure, and the torque transmission member serves as a wedge of the wedge space. The entering direction is the connecting direction, and at least one of the wedge spaces has a direction opposite to that of the other wedge spaces.

In the two-way clutch of the present invention, the torque transmission member is a torque transmission roller, and a taper is provided at an end of the torque transmission roller which faces the other of the driving body and the driven body. , Effective.

Further, in the two-way clutch of the present invention, it is effective that the torque transmission member is a torque transmission roller and both ends of the torque transmission roller are provided with taper. Furthermore, it is effective that the torque transmission member is arranged along the outer peripheral surface.

In order to solve the above-mentioned problems, the present invention provides a drive transmission device using a two-way clutch according to any one of claims 1 to 4, wherein a drive body driven by the drive source is a main body. Is a mounting member that is provided on the side of the driving body, and the driven body is detachably mounted from the rotation axis direction of the driving body, and the two-way clutch is used for drive connection between the driving body and the driven body. .

The drive transmission device of the present invention is effective when the two-way clutch is fixedly arranged on the side of the driving body. Furthermore, in order to solve the above-mentioned problems, the image forming apparatus of the present invention is the image forming apparatus using the drive transmitting apparatus according to claim 5 or 6, wherein the drive transmitting apparatus is detachable from the image forming apparatus main body. It is characterized in that it is used for drive transmission of a carrier or an image forming unit having an image carrier.

Further, in order to solve the above-mentioned problems, the image forming apparatus of the present invention is the image forming apparatus using the drive transmitting apparatus according to claim 5 or 6, wherein the drive transmitting apparatus is attached to or detached from the main body of the image forming apparatus. It is characterized in that it is used for possible drive transmission of a transfer body.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an overall schematic explanatory view showing an in-body sheet discharge type image forming apparatus as an image forming apparatus according to the present invention.

In FIG. 1, reference numeral 1 is an image forming apparatus main body, and an image forming section 2 for forming an image based on a well-known electrophotographic process is arranged in substantially the center of the apparatus main body.
A paper feed unit 3 is arranged below the image forming unit 2. The paper feeding unit 3 can be added as needed. A reading unit 5 for reading a document is disposed above the image forming unit 2 with the paper discharge storage unit 4 interposed therebetween, and the recording medium on which the image has been formed is discharged and stocked in the paper discharge storage unit 4. It

The image forming section 2 is provided with a drum-shaped photoconductor 10 as an image carrier, and a charging device 11 for performing a charging process is provided around the photoconductor 10, and image information is irradiated onto the surface of the photoconductor by laser light. Exposure device 12 for irradiating, and developing device 1 for visualizing the electrostatic latent image formed by exposure on the surface of the photoconductor 10.
3, a transfer device 14 that transfers the toner image developed on the photoconductor 10 to a sheet that is a recording medium, a cleaning device 15 that removes and collects the toner remaining on the surface of the photoconductor after the transfer, and the like. In recent years, many of the photoconductors, the charging device 11, the developing device 13, the cleaning device 15 and the like have been incorporated into one unit as a process cartridge for ease of maintenance. Also,
Reference numeral 16 is a fixing device for fixing the paper carrying the toner image after the transfer, and the paper that has passed through the fixing device 16 is ejected and accommodated in the ejection accommodating portion 4 via the ejection roller 17. .

Unused sheets are accommodated in the sheet feeding section 3, and the uppermost sheet is sent out from the sheet feeding cassette by the rotation of the sheet feeding roller 20 and conveyed to the registration rollers 21. The registration roller 21 is controlled so as to temporarily stop the conveyance of the paper and start the rotation at a timing so that the positional relationship between the toner image on the surface of the photoconductor and the front end of the paper becomes a predetermined position.

In the reading section 5, the contact glass 22
In order to read and scan a document (not shown) placed on the document, a reading traveling body including a document illumination light source 23 and a mirror 24 reciprocates. The image information scanned by the reading traveling body is read as an image signal in the CCD 26 installed behind the lens 25. The read image signal is digitized and image-processed.
Based on the image-processed signal, a laser diode (not shown) of the exposure device 12 emits light to form an electrostatic latent image on the surface of the photoconductor 10. The optical signal from the laser diode reaches the photoconductor through a known polygon mirror or lens.

Next, the drive transmission device of the present invention will be described with reference to FIG. FIG. 2 shows a simplified central cross-sectional view of an example in which the present invention is used for a driving unit of a photoconductor. The photoconductor 10 is attachable to and detachable from the image forming apparatus main body 1, and the arrow A direction is the inserting direction of the photoconductor 10 into the image forming apparatus main body 1 and the arrow B direction is its removing direction. Reference numeral 30 denotes a drive shaft as a drive member for driving the photosensitive member as a driven member, which is supported by a deep groove ball bearing 7 fixed to the rear plate 6 of the main body, and the drive shaft 30 is the main body 1 of the image forming apparatus. It is rotationally driven by a drive motor (not shown) provided inside. The photoconductor 10 inserted into the image forming apparatus main body 1 is rotated by being drivingly connected to the drive shaft 30. Then, the drive from the drive shaft 30 is transmitted to the photoconductor 10 via the two-way clutch 40 of the present invention.

FIG. 3 is a sectional view showing a two-way clutch 40 having a torque transmission roller 41 as a torque transmission member on the outer ring side.
The individual torque transmission rollers 41 are arranged in parallel on the same circumference. This two-way clutch 40 has a drive shaft 30.
Therefore, a driven cylinder 10a fitted to the outer circumference of the two-way clutch 40 is formed on the photoconductor 10. The torque transmission roller 41 has a wedge space 42 formed by the clutch housing 43, the driven cylinder 10 a, and the supports 44 and 45.
The torque transmission roller 4 is disposed in the wedge space 42.
A spring 46 is provided as a biasing member that gently pushes 1 toward the wedge side. The clutch housing 43 has a drive shaft 30 at the center thereof.
The clutch housing 43 is provided with a rotation locking groove 47 so that the drive shaft 30 can be fixed. Further, the above-mentioned supports 44 and 45 are integrally or fixed to the clutch housing 43. The two-way clutch 40 is
Although it is attached to both the driving body and the driven body, if it is fixedly mounted on the photosensitive body 10 as the driven body, it will be discarded together when the photosensitive body 10 is replaced, resulting in a large cost loss. Therefore, it is advantageous to fix the two-way clutch 40 to the driving body as in this example.

The two-way clutch constructed as described above is
In the six wedge spaces 42 in which the torque transmission rollers 41 are arranged, the adjoining spaces have opposite wedge directions. That is, every other wedge space 42 is provided so that the wedge directions are the same. Therefore, the photoconductor 1
Since 0 is transmitted through the two-way clutch 40, backlash, which tends to occur when the photoconductor 10 is stopped due to a rotational load such as a cleaning blade, can be reliably prevented, and stable drive can be achieved. Communication is obtained. Of course, such backlash cannot be prevented by the drive transmission via the one-way clutch.

FIG. 4 is a sectional view showing a two-way clutch 40 having a torque transmission roller 41 on the inner ring side. When the two-way clutch 40 is fixed to the driving body side as described above, the driving body is not a shaft but a driving cylinder, and
A driven body of 0 is composed of a shaft. The two-way clutch 40 also includes the clutch housing 43, the driven shaft 10b, and the support device 4
The six torque transmission rollers 41 arranged in the wedge space 43 formed by 4, 45 are lightly pressed in the wedge direction by the springs 46 as biasing members. In the wedge space 43, since the wedge directions of the adjacent wedge spaces are opposite to each other, the drive is transmitted in both directions. Therefore, as in the above-described embodiment, the drive of the driving body can be transmitted without backlash, so that the deterioration of the image quality due to the drive transmission can be suppressed.

In the embodiment shown in FIGS. 3 and 4,
Although six torque transmission rollers 41 are used, the number of torque transmission rollers 41 may be increased or decreased depending on the required torque. Further, the photoconductor 10 has the drive shaft 3
Although it is removably mounted from the axial direction of 0, the shaft of the photoconductor 10 may hit the end portion of the torque transmission roller 41 and be difficult to fit as shown in FIG. 5 during the mounting. Therefore, it is preferable that the torque transmission roller 41 has a tapered shape at least at the end portion facing the direction in which the photoconductor is inserted. However, if only one end of the torque transmission roller 41 is tapered, it is necessary to match the taper direction of all the torque transmission rollers 41 when the clutch is assembled. Further, the direction of the taper end portion after assembly must be correctly assembled to the driving body or the driven body. Therefore, if the two-way clutch 40 is set so that the taper side can be identified by colors, characters, symbols, etc., it is possible to reliably prevent the wrong mounting direction.

Further, as shown in FIG. 6, if the torque transmitting roller 41 is tapered not at one end but at both ends, it is advantageous because the assembling and assembling directions can be performed without paying attention. By the way, in the above-described embodiment, the driving body and the driven body are drive-coupled via the two-way clutch 40.
Similar to the above-described embodiment, drive transmission without backlash is possible by providing a single piece, and an installation example of the two overrunning clutches 60 and 61 will be described with reference to FIGS. 7 to 13.

7 and 8 show an example in which the overrunning clutches 60 and 61 are provided in series on the driving body on the image forming apparatus main body side. In FIG. 7, the driving body is composed of a driving cylinder 70, two overrunning clutches 60 and 61 having different connecting directions are provided on the inner peripheral surface of the driving cylinder 70, and the driven body-side rotating body 75 has an outer periphery thereof. The surface side is fitted so as to be in contact with the overrunning clutches 60, 61. In FIG. 8, the driving body is composed of the driving shaft 70, and the driving shaft 70 is provided with two overrunning clutches 60 and 61 having different connecting directions. The inner peripheral surface of the rotating body 75 on the driven body side is over. Running clutch 60,
Fit so as to contact 61.

9 and 10 show an example in which overrunning clutches 60 and 61 are provided in series on a driven body on the side of the photoconductor 10. In FIG. 9, the driving body is composed of a driving cylinder 70, and two overrunning clutches 60 and 61 having different connecting directions are provided on the outer peripheral surface of the rotating body 75.
0 and 61 are fitted so as to be in contact with the inner peripheral surface of the drive cylinder 70. In FIG. 10, the driving body is composed of the driving shaft 70, and two overrunning clutches 60 and 61 having different connecting directions are provided on the inner peripheral surface of the rotating body 75. The rotating body 75 has the overrunning clutch 60. , 61 so as to be in contact with the drive shaft 70.

FIG. 11 shows an example in which overrunning clutches 60 and 61 are provided on the driving body and the driven body, respectively. The overrunning clutch 60 is provided on the drive shaft 70, and the overrunning clutch 61 is the inner peripheral surface of the rotating body. It is provided in. FIG. 12 shows an example using overrunning clutches 60 and 61 having different diameters. Furthermore, in FIG. 13, two overrunning clutches 60 and 61 are arranged in parallel.

In this way, by drivingly connecting the driving body and the driven body through the two overrunning clutches 60 and 61 having different connecting directions, the same effect as in the case of drivingly coupling using the two-way clutch can be obtained. can get. However, when the overrunning clutches 60 and 61 are used, not only the number of parts is simply increased, but also when they are arranged in series or when they have different diameters, the rubbing stroke at the time of attachment / detachment becomes long, and therefore This leads to an increase in the size of the device. Also,
In the case of the parallel arrangement, there is a problem that the driving body has a large diameter. Considering these points, it can be said that using the above-described two-way clutch 40 is advantageous in terms of space, cost, and the like.

The present invention is not limited to the drive transmission of the photoconductor, but can be applied to the transfer roller and all other drive units that require easy attachment / detachment and high drive transmission. Further, although the photoconductor is attached to the main body of the image forming apparatus in the above-described embodiment, it is naturally applicable to the case where the image forming unit including the photoconductor is attached.

[0031]

According to the first aspect of the present invention, a plurality of torque transmission members which contact the other of the driving body and the driven body to transmit the rotational drive of the driving body to the driven body, and the torque transmission members are arranged. , A plurality of wedge spaces formed between the clutch housing, the driving body, and the other of the driven bodies, and an urging means for pressing the torque transmission member to the wedge side of the wedge space with a predetermined pressure. The direction in which the member enters the wedge of the wedge space is the connection direction,
Since at least one of the wedge spaces has the direction of the wedge opposite to that of the other wedge spaces, it is easy to attach and detach from the axial direction, and to provide a clutch that transmits the drive in both forward and reverse directions in the rotational direction. You can

According to the structure of claim 2, the torque transmitting member is a torque transmitting roller, and the end portion of the torque transmitting roller facing the other of the driving body and the driven body is provided with a taper. The directional mounting can be done smoothly.

According to the third aspect of the invention, the torque transmitting member is the torque transmitting roller, and the both ends of the torque transmitting roller are provided with the taper, so that the clutch can be assembled correctly.

According to the structure of claim 4, since the torque transmitting member is arranged along the outer peripheral surface, the torque transmitting member can be installed inside, so that the drive transmitting portion does not become large, which contributes to downsizing of the main body.

According to the structure of claim 5, the driving body driven by the driving source is provided on the main body side, and the driven body is a mounting member which is detachably mounted from the rotational axis direction of the driving body. Since a two-way clutch is used for driving connection between the driven body and the driven body, it is possible to provide drive transmission without backlash.

According to the structure of claim 6, since the two-way clutch is fixedly arranged on the driving body side, the expensive clutch is not discarded together with the driven body, and the total cost can be reduced.

According to the structure of claim 7, since the drive transmission device is used for drive transmission of the image carrier detachable from the image forming apparatus main body or the image forming unit having the image carrier,
It is possible to provide an image forming apparatus capable of preventing deterioration of image quality due to backlash.

According to the structure of claim 8, since the drive transmission device is used for drive transmission of the transfer body detachable from the main body of the image forming apparatus, it is possible to provide the transfer body drive means without backlash.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of an image forming apparatus using a two-way clutch according to the present invention.

FIG. 2 is a cross-sectional explanatory view showing an example of installation of a two-way clutch according to the present invention.

FIG. 3 is an explanatory sectional view showing an example of a two-way clutch according to the present invention.

FIG. 4 is a cross-sectional explanatory view showing another example of the two-way clutch according to the present invention.

FIG. 5 is an explanatory diagram showing a problem when connecting to a two-way clutch.

FIG. 6 is an explanatory view showing a main part of a two-way clutch that solves the problem of FIG.

FIG. 7 is a cross-sectional explanatory view showing an installation example of two overrunning clutches.

FIG. 8 is a cross-sectional explanatory view showing another installation example of two overrunning clutches.

FIG. 9 is a cross-sectional explanatory view showing still another installation example of the two overrunning clutches.

FIG. 10 is a cross-sectional explanatory view showing still another installation example of two overrunning clutches.

FIG. 11 is a cross-sectional explanatory view showing still another installation example of two overrunning clutches.

FIG. 12 is a cross-sectional explanatory view showing still another installation example of two overrunning clutches.

FIG. 13 is a cross-sectional explanatory view showing still another installation example of two overrunning clutches.

FIG. 14 is a perspective view illustrating a conventional photoconductor drive transmission method.

FIG. 15 is a perspective explanatory view showing another conventional method for transmitting drive of the photosensitive member.

[Explanation of symbols]

10 Photosensitive drum (driven body) 30 Drive shaft (drive body) 40 2-way clutch 41 Torque transmission roller 42 Wedge space 43 clutch housing 46 spring

Continued front page    (72) Inventor Shinichi Kawahara             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh F term (reference) 2H035 CA07 CB03 CD07 CG03                 2H171 FA04 FA09 GA08 GA11 JA02                       JA14 JA16 KA16 KA26 LA03                       LA12 LA13 QA02 QB19 QC03                       QC36 RA01 RA05 SA08 SA14                       SA18 SA22 SA26

Claims (8)

[Claims] 1. A drive unit driven by a drive source and a driven unit driven by the drive unit are fixedly arranged, and the other unit is connected to drive the drive unit. In a two-way clutch for transmitting to a body, a plurality of torque transmitting members for contacting the other of the driving body and the driven body to transmit the rotational drive of the driving body to the driven body, the torque transmitting members are arranged, and a clutch casing. A plurality of wedge spaces formed between the body, the driving body, and the other of the driven bodies, and an urging means for pressing the torque transmission member toward the wedge side of the wedge space with a predetermined pressure, A two-way clutch, wherein a direction in which a transmission member enters a wedge of the wedge space is a connecting direction, and at least one of the wedge spaces has a direction opposite to that of another wedge space. 2. The two-way clutch according to claim 1, wherein the torque transmission member is a torque transmission roller, and a taper is provided at an end of the torque transmission roller that faces the other of the driving body and the driven body. 2 characterized by
Directional clutch. 3. The two-way clutch according to claim 1, wherein the torque transmission member is a torque transmission roller, and the both ends of the torque transmission roller are provided with a taper. 4. The two-way clutch according to any one of claims 1 to 3, wherein the torque transmission member is arranged along an outer peripheral surface of the two-way clutch. 5. The drive transmission device using the two-way clutch according to claim 1, wherein a drive body driven by the drive source is provided on a main body side, and the driven body is the drive body. A drive transmission device, wherein the two-way clutch is a mounting member that is removably mounted in the direction of the rotation axis of the body, and the two-way clutch is used for driving connection between a driving body and a driven body. 6. The drive coupling device according to claim 5, wherein the two-way clutch is fixedly disposed on the drive body side. 7. An image forming apparatus using the drive transmission device according to claim 5 or 6, wherein the drive transmission device drives an image carrier detachably attached to a main body of the image forming device or an image forming unit having the image carrier. An image forming apparatus characterized by being used for transmission. 8. An image forming apparatus using the drive transmission device according to claim 5 or 6, wherein the drive transmission device is used for drive transmission of a transfer body detachable from a main body of the image forming apparatus. Forming equipment.