JP2011048243A - Driving unit, image forming apparatus using driving unit, method for assembling driving unit and assembling tool for driving unit - Google Patents

Abstract

A drive unit that achieves both optimization of the drive unit and ease of assembly work when using the drive unit in common regardless of the drive system, and an image forming apparatus using the same And an assembly method for the drive unit and an assembly jig for the drive unit.
SOLUTION: The first and second timing belts 25b1 and 25b2 for transmitting power for rotating the coupling 21 and the drive frame 26 provided with the coupling 21 and the first and second timing belts 25b1 and 25b2 are provided. In the drive unit 20 that is mounted using the belt holding member 31 that holds the first timing belt 25b1, the drive frame 26 is opposed to the first timing belt 25b1 at a position opposite the first timing belt 25b1. A through hole 27 into which the belt holding member 31 can be inserted is provided.
[Selection] Figure 3

Description

  The present invention relates to a drive unit for driving a photoreceptor or the like in an image forming apparatus, and more particularly to an image of an electrostatic copying machine, a laser pooler, a facsimile, or the like that forms an image using toner by an electrophotographic method. The present invention relates to a drive unit employed in a forming apparatus, an image forming apparatus using the drive unit, a drive unit assembly method, and an assembly jig for the drive unit.

  Conventionally, in a drive unit of an image forming apparatus that has a drive mechanism for driving a photosensitive member or the like, both transmission methods of gear drive (gear transmission) and belt drive (belt transmission) can be used by using a common drive frame. What was comprised so that it may become is known. This is a transmission system for both gear drive and belt drive in advance so that a common drive unit can be used for each product with different product specifications (copy speed, color copier or monochrome copier, product cost, etc.). Is designed to be usable.

  As a conventional technique, for example, a drive unit is disclosed in which a motor pulley is fixed to a motor shaft of a drive motor, a drive transmission pulley that transmits power of the drive motor is provided, and a timing belt is bridged between the motor pulley and the drive transmission pulley. (See Patent Document 1).

  The drive unit configured as described above requires a belt holding mechanism for holding the timing belt so that the timing belt does not fall off when the timing belt is assembled.

  When this belt holding mechanism is provided on the drive frame side of the drive unit, a gear arrangement that avoids the belt holding mechanism so that the gear member and the belt holding mechanism do not interfere with each other when the gear driving method is used, Alternatively, a belt holding mechanism is provided so as to avoid the gear arrangement.

JP-A-8-86338

  However, as described above, when the drive unit is commonly used in devices having different drive systems, for example, the gear and timing belt are mounted differently, so that the function of the drive unit is achieved (drive transmission according to product specifications). It is difficult to satisfy both of the assembly workability, and one of them is sacrificed at present.

  In addition, when the belt holding mechanism is provided in the drive unit itself, a mechanism that is not directly related to the original function of the drive unit is added, so that the configuration of the apparatus becomes complicated due to an increase in the number of components, and substantially This raises the problem of cost increase.

  The present invention has been made in view of the above-described conventional problems, and realizes both optimization of the drive unit and ease of assembly work when the drive unit is commonly used regardless of the drive system. An object of the present invention is to provide a drive unit that reduces costs, an image forming apparatus that uses the drive unit, a method for assembling the drive unit, and an assembly jig for the drive unit.

  A drive unit, an image forming apparatus using the drive unit, an assembling method of the drive unit, an assembly jig transfer device for the drive unit, and an image forming apparatus using the drive unit according to the present invention for solving the above-described problems are as follows. It is.

  The present invention comprises a drive transmission means for transmitting power for rotating the rotated member, and a drive frame provided with the rotated member and the drive transmission means, and when the drive transmission means is attached to the drive frame, In the drive unit to be mounted using the assembly jig, the drive transmission means of the assembly jig is held from a side opposite to the side where the drive transmission means is disposed at a position facing the drive transmission means of the drive frame. A through hole into which the holding member can be inserted is provided.

  In the present invention, it is preferable to use a timing belt as the drive transmission means.

  In the present invention, it is preferable that a gear can be used in place of the timing belt as the drive transmission means.

  According to another aspect of the present invention, there is provided an image forming apparatus using a drive unit including a drive transmission unit configured to transmit a drive for rotating the rotated member, and a drive frame provided with the rotated member and the drive transmission unit. The drive unit according to any one of claims 1 to 3 is used as the drive unit.

  The present invention also includes a drive transmission means for transmitting a drive for rotating the rotated member, and a drive frame provided with the rotated member and the drive transmission means, and the drive transmission means is attached to the drive frame. A drive unit assembling method for mounting using a holding member for holding the drive transmission means when attached, wherein the holding member is attached to the drive frame when the drive transmission means is attached to the drive frame. And the drive transmission means is held by the holding member.

  Further, the present invention is an assembly jig for a drive unit, comprising: drive transmission means for transmitting a drive for rotating the rotated member; and a drive frame provided with the rotated member and the drive transmission means. A positioning member that positions the assembly jig with respect to the drive frame, a holding member that positions and holds the drive transmission means with respect to the drive frame, and a base member that holds the positioning member and the holding member. The holding member is detachably provided to the base member.

  According to the present invention, when the drive transmission means is attached to the drive frame, the drive transmission means transmits power for rotating the rotated member, and the drive frame provided with the rotated member and the drive transmission means. Further, in the drive unit to be mounted using the assembly jig, the drive transmission means of the assembly jig is arranged at a position opposite to the drive transmission means of the drive frame from the side opposite to the side where the drive transmission means is disposed. By providing a through-hole into which the holding member to be held can be inserted, the driving means can be held by a holding member formed separately from the driving unit, and after the assembly, the holding member is separated from the driving unit. As a result, it is possible to achieve both optimization of the drive unit and ease of assembly work when using the drive unit in common regardless of the drive system. It is possible to reduce the cost.

  Further, according to the present invention, by using a timing belt as the drive transmission means, the timing belt can be easily attached by the holding member when the drive unit is assembled.

  In addition, according to the present invention, it is possible to use a common component among the drive units by making it possible to use a gear instead of the timing belt as the drive transmission means. That is, the drive system of the drive unit can be easily changed from belt drive to gear drive.

  In addition, according to the present invention, in an image forming apparatus using a drive unit that includes a drive transmission unit that transmits a drive for rotating a rotated member, and a drive frame provided with the rotated member and the drive transmission unit. When the drive unit according to any one of claims 1 to 3 is used as the drive unit, the drive unit is optimized and assembled when the drive unit is used in common regardless of the drive system. Thus, it is possible to realize an image forming apparatus that can achieve both of the ease of use and can reduce the cost.

  According to the present invention, there is provided a drive transmission means for transmitting a drive for rotating the rotated member, and a drive frame provided with the rotated member and the drive transmission means, and the drive transmission means is driven by the drive A drive unit assembly method for mounting using a holding member for holding the drive transmission means when attached to the frame, wherein the holding member is attached to the drive frame when the drive transmission means is attached to the drive frame. By penetrating from the side opposite to the side where the transmission means is disposed and holding the drive transmission means by the holding member, the driving means can be held by a holding member formed separately from the drive unit. Since the holding member can be separated from the drive unit after mounting, the drive unit can be used in common use regardless of the drive system. While achieve both ease of optimization and assembly of the knit, it is possible to reduce the cost.

  According to the present invention, there is provided an assembly jig for a drive unit, comprising: drive transmission means for transmitting a drive for rotating the rotated member; and a drive frame provided with the rotated member and the drive transmission means. A positioning member that positions the assembly jig with respect to the drive frame; a holding member that positions and holds the drive transmission means with respect to the drive frame; and a base that holds the positioning member and the holding member. An assembly jig for assembling the drive unit even when the drive transmission means is changed from a belt to a gear, for example, by providing the holding member detachably with respect to the base member. Since the holding member can be removed and used when using an assembly jig, the assembling jig can be shared.

1 is an explanatory diagram illustrating an overall configuration of an image forming apparatus in which a drive unit according to a first embodiment of the present invention is used. FIG. 3 is an explanatory diagram illustrating an example of a configuration of a drive unit of the image forming apparatus according to the first embodiment. It is explanatory drawing which shows the structure of the assembly jig for the said drive unit and a drive unit. It is explanatory drawing which shows the structure of the assembly jig | tool for assembling the said drive unit. It is a partial detail drawing which shows the structure of the belt holding member which comprises the said assembly jig. It is explanatory drawing which shows the state of the 1st timing belt when the said drive unit is assembled. It is explanatory drawing which shows the state which mounted | wore the said drive unit with the assembly jig. It is A arrow directional view of FIG. It is explanatory drawing which shows the structure of the drive unit which concerns on 2nd Embodiment, and the assembly jig for drive units. It is a B arrow line view of FIG. It is explanatory drawing which shows the structure of the said assembly jig.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an example of an embodiment for carrying out the invention, and is an explanatory diagram showing the overall configuration of an image forming apparatus using a drive unit according to the first embodiment of the present invention.

  In the first embodiment, as shown in FIG. 1, a photosensitive drum 3 on which an electrostatic latent image is formed, a charger (charging device) 5 that charges the surface of the photosensitive drum 3, and the photosensitive drum 3. An exposure unit (exposure device) 1 that forms an electrostatic latent image on the surface, a developing device 2 that supplies toner to the electrostatic latent image on the surface of the photosensitive drum 3 to form a toner image, and a surface of the photosensitive drum 3 A drive transmission unit that includes a transfer unit (transfer device) 6 that transfers the toner image onto a sheet (recording medium) and a fixing unit (fixing unit) 7 that fixes the transferred toner image onto the sheet. In the image forming apparatus 100 that includes a driving unit using a timing belt and forms an image using toner by an electrophotographic method, the configuration of the driving unit according to the present invention is employed.

First, the overall configuration of the image forming apparatus 100 according to the first embodiment will be described.
As shown in FIG. 1, the image forming apparatus 100 forms multicolor and single color images on a predetermined sheet (for example, recording sheet) in accordance with image data transmitted from the outside. 110 and an automatic document processing apparatus 120.

  The apparatus main body 110 includes an exposure unit 1, a developing device 2, a photosensitive drum 3, a cleaner unit 4, a charger 5, a transfer unit 6, a fixing unit 7, a paper feed cassette 81, a paper discharge tray 91, and the like. ing.

  A platen glass (original platen) 92 made of transparent glass on which an original is placed is provided above the image reading unit 90 provided on the upper part of the apparatus main body 110, and an automatic original is provided above the platen glass 92. A processing device 120 is attached.

The automatic document processing device 120 automatically conveys the document on the platen glass 92.
Further, the automatic document processing device 120 is configured to be rotatable in the direction of arrow M, and the document can be placed manually by opening the platen glass 92.

Image data handled in the image forming apparatus 100 corresponds to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y).
Accordingly, four developing devices 2, photosensitive drums 3, chargers 5, and cleaner units 4 are provided to form four types of latent images corresponding to the respective colors. Black, cyan, magenta, and yellow are respectively provided. These are set to form four image stations.

  The charger 5 is a charging means for uniformly charging the surface of the photosensitive drum 3 to a predetermined potential. In addition to a charger type as shown in FIG. 1, a contact type roller type or brush type charger is used. It may be used.

  The exposure unit 1 exposes the charged photosensitive drum 3 in accordance with image data input from the outside or image data obtained by reading from a document, thereby generating an electrostatic latent image corresponding to the image data on the photosensitive body. This is an image writing device formed on the surface of the drum 3, and is configured as an LSU (laser scanning unit) provided with a laser emitting portion, a reflection mirror, and the like. The exposure unit 1 is also provided with a polygon mirror that scans the laser beam and optical elements such as a lens and a mirror for guiding the laser beam reflected by the polygon mirror to the photosensitive drum 3.

  Further, as the exposure unit 1, in addition to the above-described configuration, for example, a method using an EL or LED writing head in which light emitting elements are arranged in an array can be employed.

  The exposure unit 1 thus configured forms an electrostatic latent image on the surface of the photosensitive drum 3 by exposing the charged photosensitive drum 3 according to the input image data. It has the function to do.

  The developing device 2 visualizes the electrostatic latent images formed on the respective photosensitive drums 3 with toners of four colors (Y, M, C, K).

  The photosensitive drum 3 has a cylindrical shape, is disposed above the exposure unit 1, the surface thereof is cleaned by the cleaner unit 4, and the cleaned surface is uniformly charged by the charger 5.

  The cleaner unit 4 removes and collects toner remaining on the surface of the photosensitive drum 3 after development and image transfer.

  The transfer unit 6 disposed above the photosensitive drum 3 includes an endless intermediate transfer belt (endless belt) 61, an intermediate transfer belt driving roller 62, an intermediate transfer belt driven roller 63, an intermediate transfer roller 64, and an intermediate transfer roller. A belt cleaning unit 65 is provided. Four intermediate transfer rollers 64 are provided corresponding to each color of Y, M, C, and K.

  The intermediate transfer belt driving roller 62, the intermediate transfer belt driven roller 63, and the intermediate transfer roller 64 are configured to stretch and drive the intermediate transfer belt 61.

  The intermediate transfer belt 61 is formed in an endless shape using a film having a thickness of about 100 μm to 150 μm, and is provided so as to contact each photosensitive drum 3. A function of forming a color toner image (multicolor toner image) on the intermediate transfer belt 61 by sequentially superimposing and transferring the toner images of the respective colors formed on the photosensitive drum 3 onto the intermediate transfer belt 61. have.

  Transfer of the toner image from the photosensitive drum 3 to the intermediate transfer belt 61 is performed by an intermediate transfer roller 64 that is in contact with the back side of the intermediate transfer belt 61.

  Each intermediate transfer roller 64 applies a transfer bias for transferring the toner image on the photosensitive drum 3 onto the intermediate transfer belt 61 with respect to the intermediate transfer belt 61. Specifically, a high voltage transfer bias (a high voltage having a polarity (+) opposite to the toner charging polarity (−)) is applied to the intermediate transfer roller 64 in order to transfer the toner image.

  The intermediate transfer roller 64 is a roller whose base is a metal (for example, stainless steel) shaft having a diameter of 8 to 10 mm and whose surface is covered with a conductive elastic material (for example, EPDM, urethane foam, or the like). With this conductive elastic material, a high voltage can be uniformly applied to the intermediate transfer belt 61. In the first embodiment, the roller-shaped intermediate transfer roller 64 is used as the transfer electrode, but a brush or the like can also be used.

  As described above, the toner images visualized according to the hues on the photosensitive drums 3 are stacked on the intermediate transfer belt 61. The stacked toner images as image information are transported together with the intermediate transfer belt 61, moved to a contact position (secondary transfer position, predetermined position) between the transported paper and the intermediate transfer belt 61, and moved to this contact position. The image is transferred onto the paper by the arranged transfer roller 10.

  At this time, the intermediate transfer belt 61 and the transfer roller 10 are pressed against each other at a predetermined nip, and a secondary transfer bias is applied to the transfer roller 10 to transfer the toner image onto the sheet. The secondary transfer bias is a high voltage having a polarity (+) opposite to the charging polarity (−) of the toner.

  Further, in order to constantly obtain the predetermined nip, the transfer roller 10 that is pressed against the intermediate transfer belt 61 at the secondary transfer position or the intermediate transfer belt drive roller that is pressed against the back side of the intermediate transfer belt 61 at the secondary transfer position. Any one of 62 is made of a hard material (metal or the like), and the other is made of a soft material such as an elastic roller (elastic rubber roller or foaming resin roller or the like).

  In the transfer process described above, the toner adhering to the intermediate transfer belt 61 by coming into contact with the photosensitive drum 3 or the toner remaining on the intermediate transfer belt 61 without being transferred onto the paper by the transfer roller 10 is used in the next process. The intermediate transfer belt cleaning unit 65 is configured to remove and collect the toner image to cause a toner color mixture.

  The intermediate transfer belt cleaning unit 65 is provided on the downstream side of the transfer roller 10 and upstream of the photosensitive drum 3 in the intermediate transfer belt conveyance direction on the path along which the intermediate transfer belt 61 is conveyed.

  The intermediate transfer belt cleaning unit 65 includes a cleaning blade 65 a as a cleaning member that contacts the intermediate transfer belt 61 and cleans the surface of the intermediate transfer belt 61. The intermediate transfer belt 61 in contact with the cleaning blade 65a is supported by an intermediate transfer belt driven roller 63 from the back side.

The paper feed cassette 81 is a tray for storing sheets used for image formation, and is provided below the exposure unit 1 of the apparatus main body 110. A manual paper feed cassette 82 capable of supplying paper from the outside is provided on the outer side of the apparatus main body 110.
A plurality of sheets used for image formation can be stacked on the manual sheet feeding cassette 82. Above the apparatus main body 110, a paper discharge tray 91 for collecting printed sheets face down is provided.

  Further, the apparatus main body 110 has a substantially vertical sheet conveyance path S for sending the sheets of the sheet feeding cassette 81 and the manual sheet feeding cassette 82 to the sheet discharge tray 91 via the transfer roller 10 and the fixing unit 7. Is provided. In the vicinity of the paper transport path S from the paper feed cassette 81 to the manual paper feed cassette 82 to the paper discharge tray 91, pickup rollers 11a and 11b, a plurality of transport rollers 12a to 12d, a registration roller 13, a transfer roller 10, and a fixing roller. Unit 7 etc. are arranged.

  The transport rollers 12 a to 12 d are small rollers for promoting and assisting the transport of paper, and are provided along the paper transport path S. The transport roller 12b functions as a paper discharge roller that discharges the paper to the paper discharge tray 91, and is therefore referred to as a paper discharge roller.

The pickup roller 11 a is provided near the end of the paper feed cassette 81, picks up paper one by one from the paper feed cassette 81, and supplies it to the paper transport path S.
The pickup roller 11 b is provided near the end of the manual paper feed cassette 82, picks up paper one by one from the manual paper feed cassette 82, and supplies it to the paper transport path S.

  The registration roller 13 temporarily holds the paper conveyed through the paper conveyance path S. The sheet has a function of conveying the sheet to the transfer roller 10 at the timing when the leading edge of the toner image on the photosensitive drum 3 is aligned with the leading edge of the sheet. That is, the registration roller 13 aligns the toner image on the intermediate transfer belt 61 to a predetermined position on the conveyed paper.

  The fixing unit 7 includes a pair of a heat roller 71 and a pressure roller 72 as a fixing roller, and the heat roller 71 and the pressure roller 72 are rotated and conveyed with a sheet interposed therebetween.

  The heat roller 71 and the pressure roller 72 are disposed to face each other, and a fixing nip portion is formed at a pressure contact portion between the heat roller 71 and the pressure roller 72.

  The temperature of the heat roller 71 is controlled by a control unit (not shown) so as to reach a predetermined fixing temperature. The controller controls the temperature of the heat roller 71 based on a detection signal from a temperature detector (non-contact type thermistor) (not shown) that detects the temperature of the heat roller 71 provided around the heat roller 71. It controls so that it may become the range of 200 degreeC.

  Further, the heat roller 71 has a function of fusing, mixing, and pressing the multicolor toner image transferred to the paper and thermally fixing the paper with the pressure roller 72 by thermally pressing the toner onto the paper. ing. As shown in FIG. 1, the heat roller 71 is provided with an external fixing belt 73 for fixing the heat roller 71 from the outside.

  On the other hand, similarly to the heat roller 71, the pressure roller 72 is also configured by providing an elastic layer on the peripheral surface of a cylindrical metal core. And it contacts with the heat roller 71 with a predetermined pressure.

Next, the drive unit constituting the image forming apparatus 100 according to the first embodiment will be described in detail with reference to the drawings.
FIG. 2 is an explanatory diagram illustrating an example of a configuration of a drive unit of the image forming apparatus according to the first embodiment, and FIG. 3 is an explanatory diagram illustrating a configuration of the drive unit and an assembly jig for the drive unit.

  The drive unit 20 of the image forming apparatus 100 according to the first embodiment is a drive unit used in the image forming unit, and drives the coupling (rotated member) 21 and the coupling 21 as shown in FIG. The coupling pulley 22, the drive motor 23, the drive pulley 24 that outputs the rotation of the drive motor 23, the drive transmission means 25 that transmits the power of the drive motor 23 to the coupling 21, and these components are attached. Drive frame 26 to be provided.

  The coupling 21 is a coupling for rotating the photosensitive drum 3, and is rotatably attached to the drive frame 26. The coupling pulley 22 is integrally attached to the rotating shaft 21 a of the coupling 21. The drive pulley 24 is integrally attached to the drive shaft 23 a of the drive motor 23.

  The drive transmission means 25 is mainly composed of a pulley unit 25a and a timing belt 25b. The pulley unit 25 a includes a first pulley 25 a 1 corresponding to the drive motor 23 and a second pulley 25 a 2 corresponding to the coupling 21. The timing belt 25b is bridged between the drive motor 23 and the pulley unit 25a, and transmits the power from the drive motor 23 side to the pulley unit 25a side. The timing belt 25b includes the first timing belt 25b1 and the pulley unit 25a and the coupling 21. A second timing belt 25b2 is provided between the pulley unit 25a and the coupling unit 21 to transmit power from the pulley unit 25a to the coupling 21.

  The coupling pulley 22 and the second pulley 25a2 are respectively provided with flanges 22a and 25a3 on one side surface to prevent the second timing belt 25b2 from falling off.

  The drive unit 20 configured as described above is assembled when the first timing belt 25b1 spanned between the drive motor 23 and the pulley unit 25a and the drive motor 23 are assembled as shown in FIG. A jig 30 is used for attachment.

  The assembly jig 30 includes a belt holding member (holding member) 31 that temporarily holds the first timing belt 25b1 and a guide pin 32 for positioning the belt holding member 31 at a predetermined position with respect to the drive frame 26. ing.

  The drive frame 26 has a through hole into which the belt holding member 31 can be inserted into a part facing the first timing belt 25b1 disposed on the drive frame 26 from the side opposite to the side on which the first timing belt 25b1 is disposed. 27 and a guide hole 28 into which the guide pin 32 is inserted. The drive frame 26 is made of a resin member.

Here, the assembly jig 30 for the drive unit will be described in detail with reference to the drawings.
FIG. 4 is an explanatory view showing a configuration of an assembly jig for assembling the drive unit according to the first embodiment, and FIG. 5 is a partial detail view showing a configuration of a belt holding member constituting the assembly jig.

  As shown in FIGS. 3 and 4, the assembly jig 30 used when assembling the drive unit 20 includes a belt holding member 31 that temporarily positions and holds the first timing belt 25 b 1 with respect to the drive frame 26, and this assembly. A guide pin 32 for positioning the jig 30 with respect to the drive frame 26 and a base member 33 for holding the belt holding member 31 and the guide pin 32 are provided.

  That is, the belt holding member 31 is positioned at a predetermined position with respect to the drive frame 26 by positioning the assembly jig 30 with respect to the drive frame 26 by the guide pins 32.

  The belt holding member 31 is formed of a metal member and has a columnar shape as shown in FIGS. 3 and 5, and is arranged at a position close to the drive motor 23 attached to the drive unit 20. Yes.

As shown in FIGS. 3, 4, and 5, a belt holding portion 31 b that holds a part of the first timing belt 25 b 1 is cut out at the tip portion 31 a of the belt holding member 31.
A threaded portion 31d is formed on the base portion 31c of the belt holding member 31 on the base member 33 side. The belt holding member 31 can be attached to and detached from the base member 33 by the screw portion 31d.

  The guide pins 32 are formed of a resin or metal member, have a cylindrical shape as shown in FIG. 4, and protrude from a plurality of locations (four locations in the present embodiment) on the base member 33.

  The base member 33 is made of an aluminum flat plate, and a screw hole 33a corresponding to the screw portion 31d of the belt holding member 31 is formed at a position where the belt holding member 31 is attached.

Next, assembly work of the drive unit 20 according to the first embodiment will be described with reference to the drawings.
6 is an explanatory view showing a state of the first timing belt when the drive unit according to the first embodiment is assembled, FIG. 7 is an explanatory view showing a state where an assembly jig is mounted on the drive unit, and FIG. FIG.

  When the drive unit 20 according to the first embodiment is assembled, as shown in FIG. 6, the coupling 21 and the pulley unit 25a are attached to the drive frame 26, and the drive transmission timing belt 25b (first timing belt 25b1, 2 timing belt 25b2) is arranged.

  The second timing belt 25b2 is bridged between the coupling 21 and the pulley unit 25a. The first timing belt 25b1 is attached to the pulley unit 25a on one side, but on the other side, since the drive motor 23 is attached from the upper side in the figure, the first timing belt 25b1 hangs down to the lower side in the figure (part indicated by a two-dot chain line). This makes it difficult to insert the first timing belt 25b1 into the drive pulley 24 of the drive motor 23, resulting in poor workability.

  In the first embodiment, when the drive unit 20 is assembled, the drive unit 20 is mounted on the assembly jig 30 and assembled.

  In the drive unit 20, a coupling 21 for driving the photosensitive drum 3 is provided on the opposite side (back side) of the drive frame 26 on the side where the drive transmission means 25 is disposed. For this reason, the assembly jig 30 supports the drive frame 26 in a lifted state so that the coupling 21 does not interfere with the base member 33.

  The guide pin 32 prevents the drive frame 26 from shifting from the assembly jig 30 in a state where the guide pin 32 is inserted into the guide hole 28 of the drive frame 26.

  As shown in FIGS. 7 and 8, the first timing belt 25b1 is held at a position close to the mounting position of the drive motor 23 by the belt holding portion 31b of the front end portion 31a of the belt holding member 31. As shown, it does not sag. Therefore, the operator can easily attach the drive motor 23 to the first timing belt 25b1 without holding the first timing belt 25b1.

  Thus, after the drive motor 23 is assembled to the first timing belt 25b1, the assembly jig 30 is removed from the drive unit 20, and the assembly operation of the drive unit 20 is completed.

  Since it comprised as mentioned above, according to 1st Embodiment, the through-hole 27 which can insert the belt holding member 31 in the drive frame 26 in the drive unit 20 was formed, and the assembly jig provided with the belt holding member 31 By assembling the drive unit 20 using 30, the drive motor 23 can be easily assembled without the first timing belt 25b1 hanging down.

  In addition, according to the first embodiment, the first timing belt 25b1 can be assembled without providing a belt holding portion in the drive unit 20, and after the drive unit 20 is assembled, the assembly is started from the drive unit 20. Since the belt holding member 31 can be separated together with the tool 30, the cost can be reduced.

(Second Embodiment)
Next, a drive unit according to a second embodiment of the present invention will be described in detail with reference to the drawings.
9 is an explanatory view showing the configuration of the drive unit and the assembly jig for the drive unit according to the second embodiment, FIG. 10 is a view as viewed from the direction of arrow B in FIG. 9, and FIG. 11 is an explanatory view showing the configuration of the assembly jig. It is.

  As shown in FIGS. 9 and 10, the drive unit 121 according to the second embodiment includes a timing belt 25 b as the drive transmission unit 125 as in the drive unit 20 according to the first embodiment. The power is transmitted using one transmission gear 125b.

  The configuration of the drive unit 121 according to the second embodiment has the same configuration as the configuration of the drive unit 20 according to the first embodiment except that the first transmission gear 125b is used. In the embodiment, components having the same configurations and functions as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The drive unit 121 is a drive unit used in the image forming unit as in the first embodiment, and as shown in FIGS. 9 and 10, the coupling 21 and the coupling pulley 22 that drives the coupling 21. A drive motor 23, a drive gear 124 that outputs the rotation of the drive motor 23, a drive transmission means 125 that transmits the power of the drive motor 23 to the coupling 21, and a drive frame 26 to which these components are attached. I have.

The drive gear 124 is integrally attached to the drive shaft 23 a of the drive motor 23.
The drive transmission means 125 is mainly composed of a pulley / gear unit 125a, a first transmission gear 125b, and a second timing belt 25b2.

The pulley / gear unit 125 a includes a second transmission gear 125 a 1 corresponding to the drive motor 23 and a transmission pulley 125 a 2 corresponding to the coupling 21.
The first transmission gear 125b transmits power from the drive motor 23 side to the pulley / gear unit 125a side. The second timing belt 25b2 transmits power from the pulley / gear unit 125a side to the coupling 21 side.

  The transmission pulley 125a2 is provided with a flange 125a3 on one side surface to prevent the second timing belt 25b2 from falling off together with the flange 22a of the coupling pulley 22.

  When the drive unit 121 configured as described above is assembled with the drive motor 23 and the first transmission gear 125b disposed between the drive motor 23 and the pulley / gear unit 125a, FIG. 9 and FIG. As shown, the assembly jig 30 is used for attachment as in the first embodiment.

  As the assembly jig 30 used in the second embodiment, as shown in FIG. 11, one obtained by removing the belt holding member 31 from the base member 33 is used.

  That is, in the drive unit 121, when the belt holding member 31 is attached to the assembly jig 30, as shown in FIGS. 9 and 10, the first transmission gear 125b attached to the drive frame 26, the belt holding member 31, and the like. Interfere. Therefore, the first transmission gear 125 b can be attached to the drive frame 26 by removing the belt holding member 31 from the assembly jig 30.

Next, assembly work of the drive unit 121 according to the second embodiment will be described with reference to the drawings.
When assembling the drive unit 121 according to the second embodiment, as shown in FIG. 9 and FIG. 10, the coupling 21 and the pulley / gear unit 125a are attached to the drive frame 26, and the first transmission gear 125b for drive transmission and A second timing belt 25b2 is disposed.

  The second timing belt 25b2 is bridged between the coupling 21 and the pulley / gear unit 125a. The first transmission gear 125b is rotatably supported by the support shaft 125b1 at a position close to the mounting position of the drive motor 23, and is held without dropping by the gear holding portion 125b2 formed on the support shaft 125b1. Yes. Thus, since the 1st transmission gear 125b is supported by the spindle 125b1, the drive motor 23 can be attached easily.

  Thus, after the drive motor 23 is assembled to the first transmission gear 125b, the assembly jig 30 is removed from the drive unit 121, and the assembly operation of the drive unit 121 is completed.

  As described above, according to the second embodiment, the assembly jig 30 in which the belt holding member 31 is removed even if the drive unit 121 is a drive system including a gear drive using the first transmission gear 125b. By using this, the drive unit 121 can be easily assembled.

  Therefore, in the drive unit using the gear drive system in addition to the belt drive system like the drive unit 121 of the second embodiment, it is used when assembling the drive unit using the belt drive system like the drive unit 20 of the first embodiment. The assembly jig 30 can be used in common.

Here, a drive unit used in the image forming apparatus will be described.
In an image forming apparatus, newly designing and manufacturing a drive unit corresponding to a drive system for each product (apparatus) has many losses in terms of business efficiency and product cost. For this reason, it is desirable to use a drive unit that is completely common to multiple products, but it is completely compatible with each product that has different product specifications (color copier or monochrome copier, copy speed, product cost, etc.). Can not be shared. Therefore, it is designed in advance so that it can be changed to use the drive unit in common.

  The drive unit 20 in the first embodiment employs a belt drive system. On the other hand, the drive unit 121 according to the second embodiment employs a gear drive system in addition to the belt drive system. Specifically, in the second embodiment, a timing belt is used for drive transmission with a high copying speed, and a gear is used for slow drive transmission.

  The assembly unit 30 shown in FIG. 4 is used to assemble the drive unit 20 in the first embodiment, and the belt holding member 31 shown in FIG. 9 is removed to assemble the drive unit 121 in the second embodiment. A jig 30 is used.

  Therefore, according to the above-described embodiment, the drive unit can be optimized and assembled by using a common assembly jig and using a common assembly jig even if the drive unit has a different drive system. While realizing both ease of work, cost can be reduced.

  In the above-described embodiment, the timing belt (second timing belt 25b2) is used to drive the coupling 21, but a gear may be used.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments and modifications thereof, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the respective technical means disclosed in the above embodiments are also included in the technical scope of the present invention.

  For example, in the above-described embodiment, the present invention is applied to a color image forming apparatus (multifunction machine, pulley, etc.). However, if a drive unit is used, other image forming apparatuses such as a monochrome image forming apparatus are used. The present invention can also be applied to an image forming apparatus.

20, 121 Drive unit 21 Coupling 21a Rotating shaft 22 Pulley for coupling 23 Drive motor 24 Drive pulley 25 Drive transmission means 25a Pulley unit 25a1 First pulley 25a2 Second pulley 25b Timing belt (drive transmission means)
25b1 first timing belt (drive transmission means)
25b2 Second timing belt (drive transmission means)
26 Drive frame 27 Through hole 28 Guide hole 30 Assembly jig 31 Belt holding member (holding member)
31b Belt holding portion 32 Guide pin 33 Base member 100 Image forming apparatus 124 Drive gear (drive transmission means)
125 Drive transmission means 125a Pulley / gear unit 125a1 Second transmission gear (drive transmission means)
125a2 transmission pulley 125b first transmission gear (drive transmission means)

Claims (6)

A drive transmission means for transmitting power for rotating the rotated member; and a drive frame on which the rotated member and the drive transmission means are provided. When the drive transmission means is attached to the drive frame, an assembly jig is provided. In the drive unit to be installed using
The drive frame includes a through hole at a position facing the drive transmission means, into which a holding member for holding the drive transmission means of the assembly jig can be inserted from the side opposite to the side where the drive transmission means is disposed. A drive unit characterized by that.   The drive unit according to claim 1, wherein a timing belt is used as the drive transmission unit.   The drive unit according to claim 2, wherein a gear can be used in place of the timing belt as the drive transmission means. In an image forming apparatus using a drive unit including a drive transmission unit that transmits a drive for rotating a member to be rotated, and a drive frame provided with the member to be rotated and the drive transmission unit.
An image forming apparatus using the drive unit according to claim 1 as the drive unit. A drive transmission unit configured to transmit a drive for rotating the rotated member; and a drive frame provided with the rotated member and the drive transmission unit, wherein the drive transmission unit is mounted when the drive transmission unit is attached to the drive frame. A method for assembling a drive unit to be attached using a holding member for holding a transmission means,
When attaching the drive transmission means to the drive frame, the holding member is penetrated from the opposite side of the drive frame to the side where the drive transmission means is disposed, and the drive transmission means is held by the holding member. Assembling method of the drive unit. An assembly jig for a drive unit, comprising: drive transmission means for transmitting drive for rotating the rotated member; and a drive frame provided with the rotated member and the drive transmission means,
A positioning member for positioning the assembly jig with respect to the drive frame, a holding member for positioning and holding the drive transmission means with respect to the drive frame, and a base member for holding the positioning member and the holding member; With
An assembly jig for a drive unit, wherein the holding member is detachably attached to the base member.

Images