JPH0361230A - Sheet feeding roller unit and its mounting/dismounting mechanism - Google Patents

Abstract

PURPOSE:To facilitate mounting/demounting of a sheet feeding roller unit to and from a device main body by constituting the sheet feeding roller unit so as to support it with a support shaft projected from a drive gear on the side of the main body and to position it with an engagement member. CONSTITUTION:A bearing member 11 of a sheet feeding roller unit 5 is engaged to a projected part 28a of a support shaft 28 of a drive gear 29 provided on the side of the main body. By doing this, driven gears 20, 21 are interlocked with the drive gear 29 and a hook part 16 of a support plate 15 of the sheet feeding roller unit 5 is hooked to a hook part 35 of a hook piece 31 with a lever provided on the side of the main body. The sheet feeding roller unit 5 is positioned and installed in this way on an installation drive device 25 on the side of the main body. Additionally, by way of moving this hooked-up state, a bearing member 17 is extracted from the support shaft 28 and the sheet feeding roller unit 5 is removed from the installation drive device 25 on the side of the main body.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a paper feed roller that is detachably attached to a device body and is used to feed cut sheets to an image forming device such as a copying machine or a printer. The present invention relates to a unit and a mechanism for attaching and detaching the unit to an apparatus main body.

[Conventional technology]

Generally, paper feeding devices used to feed cut sheets in image forming devices such as copying machines and printers separate and feed cut sheets loaded in a sheet cassette one by one. A retard-type sheet separation and feeding mechanism is used, which includes a paper roller, a retard roller, and the like.

(Problems to be Solved by the Invention) By the way, in a paper feeding device equipped with a retard-type sheet separation and feeding mechanism, the material and shape of the paper feeding roller and retard roller play an important role, and if deformed, separation and feeding will occur. This significantly reduces the feeding performance.Therefore, if the paper feed roller or retard roller wears out during operation, they must be replaced.

However, in conventional paper feeding devices, the paper feeding roller and retard roller are attached to a drive shaft that is supported via bearings in the frame of the device body, so when replacing the paper feeding roller and retard roller, However, there was a problem in that the bearing was removed from the main body frame, separated from the apparatus main body, and then removed from the drive shaft and replaced, which was extremely complicated work.

The present invention has been made in order to solve the above-mentioned problems in conventional paper feeding devices.The present invention has been made in order to solve the above-mentioned problems in conventional paper feeding devices.The paper feeding roller or the paper feeding roller and the retard roller are made into a unit, and can be easily attached to and detached from the main body of the device with a simple structure. It is an object of the present invention to provide a paper feed roller unit configured as above and a mechanism for attaching and detaching the same.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention provides a paper feed roller for feeding the sheets by contacting the stacked sheets on the sheet stacking plate and meshing with a drive gear provided on the main body side. a driven gear for transmitting driving force to the paper feed roller; a roller support shaft that communicates with and rotatably supports the paper feed roller and the driven gear; and a roller support shaft fixed to one end of the roller support shaft. A paper feeding roller unit comprising a support plate and a bearing member having one end fixed to the support plate and fitting to a support shaft protruding from a drive gear on the main body side, the bearing member being connected to the main body side. By fitting into the support shaft provided on the side, the driven gear becomes engaged with the drive gear on the main body side, and the paper feed roller unit is locked by the locking member provided on the main body side, so that the paper feed roller unit is engaged with the drive gear on the main body side. so that it will be installed on! #
It is something to be warned against.

[Effect]

In the paper feed roller unit configured as described above, by fitting the bearing member into the protrusion of the support shaft of the drive gear provided on the main body side, the driven gear is meshed with the drive gear, and the locking member is engaged with the drive gear. It is locked and positioned and installed. Moreover, by releasing the locked state by the locking member, the bearing member can be pulled out from the support shaft and the paper feed roller unit can be easily removed.

〔Example〕

Examples will be described below. FIG. 1 is a plan view showing a state in which an embodiment of the paper feed roller unit according to the present invention is attached to the main body of an image forming apparatus, and #l! This shows how the loaded cant sheets are being fed one by one. In the figure, 1 is a sheet cassette, 2 is a sheet R placing plate, one end of which is the sheet cassette 1.
It is swingably attached around a support shaft (not shown) provided on the side plate of the. A coil spring 3 is compressed and disposed between the lower surface of the sheet placement plate 2 and the bottom plate of the sheet cassette 1, and the sheet placement plate 2 is always rotated clockwise around the spindle by this coil spring 3. The paper feed roller 6 of the paper feed roller unit 5 presses the sheets 4 stacked on the sheet placement plate 2 against the paper feed roller 6 of the paper feed roller unit 5.

Reference numeral 7 denotes a retard roller, which is constructed by press-fitting a cylindrical rubber member onto the outer periphery of a plastic cylindrical core member, and a retard roller shaft 9 that is fixed to the retard roller support frame 8 via a torque spring (not shown). is supported by The retard roller support frame 8 is rotatably supported by a support shaft 10 that is supported by the apparatus main body and is urged to rotate clockwise, and a pin 11 protruding from the support shaft IO is engaged with the support frame 8. Then, the support frame 8 is rotated and biased clockwise, and the retard roller 7 is driven by the retard drive roller 12 of the paper feed roller unit 5.
It is configured so that it comes into pressure contact with the

The retard roller 7 is a retard drive roller 12.
When the sheet is rotated by the drive roller 12 only when it is in direct contact with the sheet and is nipping the sheet,
Rotation is prevented by the action of the torque spring. As a result, the upper sheet 4 stacked on the sheet placement plate 2, which has been forward conveyed by the rotation of the paper feed roller 6, is further advanced by the retard drive roller 12, but if multiple sheets 4 are fed at the same time. When this happens, the other sheets except for the topmost sheet are prevented from advancing by the frictional force with the non-rotating retard roller 7, and double feeding is prevented.

As shown in FIG. 2, the paper feed roller unit 5 includes a support plate 15, and a locking portion 16 is formed on the side edge of the support plate 15, and a sliding bearing 17 and the paper feed roller 6
and two support shafts 18.1 for the retard drive roller 12.
9 are arranged in parallel with each other fixed at one end. The paper feed roller 6 and the retard drive roller 12 are rotatably supported on the two support shafts 18 and 19, respectively. Note that the paper feed roller 6 and the retard drive roller 12 are each integrally provided with driven gears 20 and 21 at one end of their core members.

The paper feed roller unit 5 configured as described above is mounted on a paper feed roller unit mounting drive device 25 provided on the main body side of the apparatus shown in FIG. In FIG. 3, 26 is a beam plate provided on the main body of the device,
A support plate 27 is fixed to this beam plate 26. A drive shaft 2B, which is rotatably driven by a drive source (not shown), is rotatably supported on the support plate 27, and the tip end 28a of the support shaft 2B protrudes from the support plate 27. 28
A drive gear 29 is fixedly installed along the support plate 27 on the protruding side. Further, the support plate 27 is formed with an oval-shaped locking hole 30 for locking the other end of the support shaft 19 of the retard drive roller 12 of the paper feed roller unit 5. Note that the support shaft 28
The tip portion 28a does not necessarily have to be integrated with the support shaft 28, and may be configured to protrude from the drive gear 29 separately from the support shaft 28.

A locking piece 31 with a lever made of plastic is attached to the lever plate 26. This lever-equipped locking piece 31 is composed of a locking piece main body 32 and a lever 33 that is integrally formed upright at one end of the main body 32. A locking part 35 consisting of a notch step and a hook-shaped bent part 36 are formed at the tip corner of the piece 34 (see FIG. 4).
is brought into contact with the surface of the beam plate 26, and the tip of the hook-shaped bent portion 36 is made to protrude from the engagement hole 37 formed in the beam plate 26,
The fixing portion 38 protruding from the base of the lever 33 is fixed to the beam plate 26 so that it can be engaged with the edge of the engagement hole 37, and the locking piece main body 3 is engaged with the left and right movement of the tip of the lever 33.
The second locking portion 35 can be moved up and down.

FIG. 4 shows a state in which the paper feed roller unit 5 is mounted on the mounting drive device 25, in which the protrusion 28a of the drive support shaft 28 is fitted into the slide bearing 17, and the end of the retard drive roller support shaft 19 is shown in FIG. The locking hole 3 of the support plate 27 of the beam plate 26
0 (see FIG. 1), and the driven gears 20 and 21 of the paper feed roller 6 and retard drive roller 12 are engaged with the drive gear 29, and the support plate 15 of the paper feed roller unit 5 is engaged. The stop portion 16 is locked to the lock portion 35 of the lever-equipped locking piece 31 fixed to the beam plate 26, whereby the paper feed roller unit 5 is positioned and mounted on the mounting drive device 25 on the main body side. .

Next, the operation of attaching and removing the paper feed roller unit 5 configured as described above to the main body of the apparatus will be explained. First, when installing the paper feed roller unit 5, first install the sliding bearing 1.
Attach the opening of 7 to the main body side and attach it to the drive shaft 28 of the drive device 25.
While applying the tip of the protruding portion 28a of Press it against the base of 33 cases. Then, using the locking piece main body 32 and the protruding tip 28a of the drive shaft 28 as guides, slide it to the right in FIG. 3.

When the tip of the slide bearing 17 reaches a position where it comes into contact with a drive gear 29 fixed to a drive support shaft 28, the driven gear 20 of the paper feed roller 6 and the driven gear 21 of the retard drive roller 12 are connected to this drive gear 29. are engaged with each other, and the tip of the support shaft 19 of the retard drive roller 12 is inserted into the locking hole 30 formed in the support plate 27 of the mounting drive device 25, thereby stopping the rotation of the paper feed roller unit 5. . In this state, the locking portion 35 of the locking piece main body 32 engages with the locking portion 16 of the support plate 15 of the paper feed roller unit 5, thereby positioning in the thrust direction, that is, the axial direction,
Attachment of the paper feed roller unit 5 to the main body is completed in the state shown in FIG. 4.

Next, when removing the paper feed roller unit 5 from the main body for replacement etc., in the installed state shown in FIG.
Driven gear 20 of paper feed roller 6 of paper feed roller unit 5
By pinching and applying force to the tip of the lever 33 of the locking piece 31 with both fingers, the lever 33 is displaced in the direction of the arrow, and the locking piece main body 32 is moved in the direction of the arrow. Support of the locking portion 35 and the paper feed roller unit 5 vi
, 15 are disengaged from the locking portion 16. As a result, the paper feed roller unit 5 is moved to the left, the sliding bearing I7 is pulled out from the protruding tip 28a of the drive shaft 28, and the paper feed roller unit 5 is removed from the main body of the apparatus.

〔Effect of the invention〕

As described above based on the embodiments, according to the present invention, the paper feed roller unit is supported by the support shaft protruding from the drive gear on the main body side, and is configured to be positioned by the locking member. It has a simple structure and can be easily attached to and detached from the main body of the device.

In addition, since the paper feed roller and retard drive roller are integrally combined to form the paper feed roller unit, it is possible to easily replace the paper feed roller and retard drive roller that require replacement. Become.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the paper feed roller according to the present invention, and shows a mode in which it is attached to the main body of the apparatus and feeds sheets from a sheet cassette. FIG. 3 is a perspective view showing the attachment drive device for the paper feed roller unit on the apparatus main body side, and FIG. 4 shows the paper feed roller unit installed in the apparatus main body. This is a cross-sectional view. In the figure, 1 is a sheet cassette, 2 is a sheet mounting plate,
4 is a loaded sheet, 5 is a paper feed roller unit, 6 is a paper feed roller, 7 is a retard roller, 12 is a retard drive roller, 15 is a support plate, 16 is a locking part, 17 is a sliding bearing, 1
8 is a paper feed roller support shaft, 19 is a retard drive roller support shaft, 20.21 is a driven gear, 25 is a mounting drive device, 2
6 is a temporary beam, 28 is a drive shaft, 28a is a protruding tip, 2
9 is a drive gear, 3o is a locking hole, 31 is a locking piece with a lever,
32 is a locking piece main body, 33 is a lever, and 35 is a locking portion.

Claims (1)

[Claims] 1. A paper feed roller for feeding sheets by contacting stacked sheets on a sheet stacking plate and a drive gear provided on the main body side to mesh with the paper feed roller. a driven gear for transmitting driving force, a roller support shaft that communicates and rotatably supports the paper feed roller and the driven gear, and a support plate fixed to one end of the roller support shaft; A paper feed roller unit comprising a bearing member having one end fixed to the support plate and fitting to a support shaft protruding from a drive gear on the main body side, the bearing member being provided on the main body side. By fitting the driven gear to the supporting shaft, the driven gear becomes engaged with the drive gear on the main body side, and the paper feed roller unit is locked by the locking member provided on the main body side and is attached to the main body side. A paper feed roller unit characterized by being configured as follows. 2. In the paper feed roller unit according to claim 1, the support plate further rotatably supports a retard drive roller and its driven gear, and when the paper feed roller unit is mounted on the main body side, the drive roller on the main body side is A paper feed roller unit characterized in that the driven gear of the retard drive roller is configured to mesh with a gear. 3. A paper feed roller for feeding sheets, a driven gear for transmitting driving force to the paper feed roller, and a roller that communicates with and rotatably supports the paper feed roller and the driven gear. In a mechanism for attaching and detaching a paper feed roller unit to and from the main body of the apparatus, the mechanism includes a support shaft, a support plate fixed to one end of the roller support shaft, and a bearing member fixed to one end of the support plate. A drive gear that meshes with the driven gear of the paper feed roller, a support shaft that protrudes from the drive gear and engages with the bearing member, and a removable locking member that locks the paper feed roller unit. By fitting the bearing member of the paper feed roller unit to the support shaft on the main body side and meshing the driven gear with the drive gear, the locking member engages with the paper feed roller unit and the roller unit is rotated. 1. An attachment/detachment mechanism for a paper feed roller unit, which is attached to a main body and is capable of being removed from the main body by disengaging a locking member.