JPH0696413B2 - Paper feed roller mechanism of image forming apparatus - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding roller mechanism of an image forming apparatus, and more specifically, it forms an electrostatic latent image on an electrophotographic photosensitive member to form an electrostatic latent image. The present invention relates to a paper feed roller mechanism of an image forming apparatus such as an electrostatic copying machine that develops toner into a toner image or an electrostatic printing machine.

<Prior Art and Problems to be Solved by the Invention> Conventionally, as the paper feed roller mechanism, the paper is loaded in a cassette case or comes in contact with a paper stacked on a paper loading table such as a tray, and It is known to feed sheets one by one to a sheet feeding / conveying path. In such a paper feed roller mechanism, a roller support shaft is detachably incorporated so that replacement or the like can be easily and quickly performed when the roller is worn.

For example, in the one disclosed in Japanese Patent Laid-Open No. 59-186841, one end of the roller support shaft is fitted into a bearing attached to the side plate, and the other end of the support shaft has one of the support shafts. The pressurizing means for urging toward the shaft end and the pressure releasing means for releasing the urging force by the pressurizing means are provided. By operating these means, the roller support shaft can be attached and detached. It is provided so that you can.

By the way, in the one disclosed in the above publication, when the roller support shaft is removed, the roller support shaft is moved in the axial direction, one end is extracted from the bearing, and then it is swung upward, and the other end side is removed from the side plate. Procedures are needed. However, one end of the roller support shaft is directly connected to the drive shaft mounted on the one side plate, and at least the other end is supported by the other side plate, so that the roller support shaft is bridged between the side plates of the device. The total length becomes longer. In this case, in addition to performing the above-mentioned operation in a narrow device, both ends of the roller support shaft may hit or be caught by a component inside the device, resulting in poor workability of removal.

Further, in the one disclosed in the above publication, the other end of the roller support shaft is supported by the other side plate, but since one end is directly connected to the drive shaft, in order to prevent eccentricity, the roller support shaft and the drive shaft are prevented. High fitting precision is required for the connection with. In this case, the roller support shaft and the drive shaft are provided in a structure in which they are fitted tightly to each other, and there is a problem that when the roller support shaft is fitted into the drive shaft in a narrow device, it is very difficult to work. It was

The present invention has been made in view of the above problems, and an object of the present invention is to provide a paper feed roller mechanism of an image forming apparatus capable of easily attaching and detaching a roller support shaft even inside a narrow apparatus. And

<Means for Solving the Problems> As a paper feed roller mechanism of an image forming apparatus of the present invention for achieving the above object, a drive shaft and a paper feed roller are disposed in an intermediate portion, and a shaft end of the drive shaft is provided. A roller support shaft having one end opposed to each other, a bearing fitted to both ends of the roller support shaft, and a bearing support for supporting the bearing so that the bearing or the roller support shaft can be engaged and disengaged by lateral movement. A joint, the drive shaft and the roller support shaft are separably connected by the movement in the axial direction, and a joint that restricts the movement of at least one of the bearing and the roller support shaft in the axial direction. The connection point between the roller support shaft and the roller support shaft is set between the side plates of the image forming apparatus main body.

<Operation> According to the paper feed roller mechanism of the image forming apparatus having the above-described configuration, the roller support shaft can be provided between the side plates of the apparatus main body so as to be separable from the drive shaft via the joint. It is not necessary to bridge between the side plates, and the length can be sufficiently shortened.

Further, since the bearing is preliminarily fitted and inserted into the roller support shaft,
When mounting the roller support shaft, it is not necessary to connect the bearing and the roller support shaft under a high fitting precision.

<Example> Hereinafter, a more detailed description will be given with reference to the accompanying drawings. FIG. 1 is a perspective view showing an embodiment of a paper feed roller mechanism according to the present invention.

First, for convenience of description, a laser printer apparatus as an image forming apparatus to which the paper feed roller mechanism is applied will be briefly described with reference to FIG.

In FIG. 7, the apparatus main body (1) has an upper frame (2) equipped with an ejected paper stacking portion (4) at the time of cassette feeding on the upper surface.
And a lower frame (3) provided with a cassette loading port (3a) into which a cassette case (5) for storing sheets is loaded, and these are configured to be pivotable at a predetermined angle by a hinge part (not shown). On the left side of the upper frame (2) in the figure,
A paper discharge conveyance path (8) is configured by the paper discharge tray portion (6) for manual paper feeding and the guide portion (7) inside the upper frame. Also, the side wall (9) on the right side of the lower frame (3) in the figure
A plurality of ribs (10) for paper feed guides are formed in the paper, and a curved paper feed conveyance path (12) is formed by cooperation with adjacent ribs (11) and the like. Reference numeral (19) in the figure indicates a manual paper feed tray unit.

On the other hand, inside the printer, an optical system (13) including a laser oscillator is incorporated in the upper part, and an electrostatic latent image is formed in the central part by being exposed by the optical system (13). The photoconductor drum (14) is arranged. In addition, around the photosensitive drum (14), the photosensitive drum (1
A well-known charging corona discharger (15), a developing device (16), a transfer corona discharger (17), a cleaning device (18) and the like which form a process unit together with 4) are arranged.

Then, above the leading end of the apparatus body (1) on the paper feed side, the paper placed on the mounting plate (21) of the cassette case (5) is brought into contact with the paper feed path (12). ), That is, a paper feed roller mechanism (20) according to the present invention.

In FIGS. 1 and 2, the paper feed roller mechanism (20) has a drive shaft (30) and a roller support in which one end portion (32a) of the drive shaft (30) is opposed to the shaft end of the drive shaft (30). Axis (32)
And are included. The drive shaft (30) is for transmitting rotational drive to the roller support shaft (32), is connected to a drive system (not shown), and is rotatably supported by the side plate (31). It is extended inside the (31).

As can be seen from FIGS. 2 and 5, the end portion (30a) of the drive shaft (30) facing the roller support shaft (32) has a double leg shape bent in a U shape at the base end portion. The spring (42) is loaded. A bulging portion (42a) is provided on the leg portion of the spring (42). Further, a through hole (30b) for allowing the bulging portion (42a) of the loaded spring (42) to project to the outside of the peripheral surface is formed on the peripheral surface of the opposed end portion (30a). The bulging portion (42a) projects outward and engages with a joint (50), which will be described later, and fixes the joint at a predetermined position.

The roller support shaft (32) is a driven shaft to the drive shaft (30), and a pair of paper feed rollers (34) (34) are axially moved and circumferentially arranged at predetermined intervals in an intermediate portion. It is fixed in a state in which rotation to is restricted. Both ends (32a) (32b) of the roller support shaft (32) are supported by a pair of bearings (36) (37) in the same shape. A bearing (36) fitted and inserted on the one end (32a) side of the roller support shaft (32)
Is provided movably in the axial direction with respect to the roller support shaft (32) so that it can be independently removed from the bearing support portion (40) described later (see arrow (a) in FIG. 2). The other end (32
The bearing (37) fitted into the b) side is fixed by a stop ring (38) so as not to move in the axial direction.

An engagement pin (44) is provided in a radial direction on the one end (32a) side of the roller support shaft (32) and on the shaft end side of the bearing (36) fitted and inserted therein. ing. The engagement pin (44) engages with a joint (50) described later to ensure the meshing during the rotation of the shafts, and also the bearing (36).
It serves as a stopper to prevent the spring from falling off. For example, a spring pin is used as a roller support shaft (32).
It can be configured by press-fitting in the radial direction.

On the other hand, at a predetermined position of the apparatus main body (1), the bearing (36) is detachably supported by moving the bearing (36) alone or in the axial direction together with the roller support shaft (32). Bearing support parts (40) (40) are attached (see FIG. 3). Specifically, the bearings (36) (37) are formed in a block shape composed of substantially rectangular six faces, and both side faces of the bearings (36) (37) engage with engaging holes (40a) described later. Dowel pin (3
6a) (37a) is projected horizontally. On the other hand, the bearing support part (40) is formed in a frame shape that surrounds the bearings (36) (37) from above along both side surface parts thereof, and corresponds to the side surface parts of the bearings (36) (37). The support piece (40b) is provided with an engagement hole (40a) that is open to the drive shaft (30) side and is cut in the axial direction.

Next, the one end portion (32a) of the roller support shaft (32) and the opposite end portion (30a) of the drive shaft (30) are connected by a joint (50) made of a tubular body having openings at both ends. That is, the joint (50) transmits the rotational drive of the drive shaft (30) to the roller support shaft (32) and is detachably connected between the side plates of these device main bodies by moving in the axial direction. Therefore, the length of the roller support shaft (32) is shortened. The joint (50) is fixed to the end of the drive shaft (30) by the spring (42) and one end of the joint (50) can contact the bearing (36). Therefore, the joint (50) prevents the bearing (36) fitted to the one end portion (32a) side of the roller support shaft (32) from moving in the axial direction, so that the bearing support portion (40) is not prepared. You can prevent them from leaving.

At the position corresponding to the engagement pin (44) at the end of the joint (50) on the roller support shaft (32) side, as shown in FIGS. 2 and 5, the cutout hole (50a) is formed. ) Has been formed. When the joint (50) and the roller support shaft (32) are fitted together, the notch hole (50a) introduces the engagement pin (44) from the above end portion to the inner depth portion along the axial direction, and drives the drive shaft. This is for surely transmitting the driving force of (30) to the roller support shaft (32). Also, the drive shaft (3
A through hole (50b) is formed at the end on the (0) side. As the through hole (50b), when the joint (50) and the drive shaft (30) are fitted with each other, and the roller support shaft (32) is fitted with the engagement pin (44), the engagement pin (44) is at a predetermined introduction position. When it comes to, it engages with the bulging portion (42a) of the spring (42) (see FIG. 3). The joint (50) is provided with a predetermined fitting gap with respect to the roller support shaft (32) in order to eliminate the need for fitting accuracy.

Next, a procedure for removing the roller support shaft (32) in the paper feed roller mechanism of the image forming apparatus will be described. As shown in FIGS. 1 and 5, when the roller support shaft (32) is connected to the drive shaft (30) by the joint (50), first, the joint (50) is moved to the drive shaft (30) side. To move.
At this time, the spring (42) is pushed inward by the edge of the through hole (50b) of the moving joint (50), and the engagement state with the joint (50) is smoothly released (Fig. 4 ( See A) and FIG. 6). Further, as shown in FIG. 4 (A), the engagement pin (44) is pulled out from the cutout hole (50a) to release the engagement, and the roller support shaft (32) of the joint (50) is released. The end on the side is separated from the bearing (36) and the position regulation of the bearing (36) is released.

Next, the bearing (36) that has become possible to move in the axial direction.
Is moved to the drive shaft (30) side and removed from the bearing support (40) (see FIG. 4 (B) and FIG. 6). Then, after slightly moving one end portion (32a) of the roller support shaft (32) in the direction of the downward arrow (b) of FIG. 4B, the roller support shaft (32) is attached to the drive shaft (30) side. Pull to. Accordingly, the bearing (37) supporting the other end (32b) of the roller support shaft (32) is integrally removed from the bearing support part (40), and the roller support shaft (32) can be taken out. Complete.

The procedure for attaching the roller support shaft (32) may be carried out in the reverse order of the above. In general, first, operate the bearing (36) on the one end (32a) side with a finger. After supporting the roller support shaft (32) from below, sandwiching the roller support shaft (32) from below in a possible state, and then supporting the bearing (37) with the corresponding bearing support part (40).
To support. Next, with the roller support shaft (32) supported from below, the bearing (36) is moved in the axial direction and engaged with the corresponding bearing support portion (40). As a result, the roller support shaft (32) is temporarily temporarily fixed to the bearing support portions (40) (40) via the bearings (36) (37). At this time, one end (32a) of the roller support shaft (32) is connected to the drive shaft (3
It is possible to face the opposite end (30a) of (0). Then, next, the joint (50) on the drive shaft (30) side is moved to the roller support shaft (32) to connect the roller support shaft (32) and the drive shaft (30).

At this time, the bulging part (42a) of the spring (42) is elastically fitted into the through hole (50b) of the moving joint (50), so that the joint (50) is fixed to the drive shaft (30). It is fixed in the position, and at the same time, the opposite end (30a) of the joint (50) abuts the bearing (36) supported by the bearing support (40). At this time, the bearing (36) is positionally regulated by the opposing end (30a) of the joint (50) to prevent movement in the axial direction, and is securely fixed to the bearing support (40) for mounting. Complete.

In the paper feed roller mechanism having the above structure, the roller support shaft (32) is connected to the joint (5
Since the drive shaft (30) can be separated from the drive shaft (30) via the shaft (0), the roller support shaft (32) can be shortened. According to this, even if it is necessary to tilt the roller support shaft (32) when mounting and dismounting the roller support shaft (32), the tilt is very small, and the contact and catching with the internal components of the device are prevented. It can be lost.

Further, since the bearings (36) (37) are fitted in the roller support shaft (32) in advance, when the roller support shaft (32) is attached, the bearing and the roller support shaft should be connected to each other with high fitting accuracy. It can be unnecessary.

8 and 9 show another embodiment according to the present invention. In the paper feed roller mechanism shown here, compared to the above-described embodiment, the one bearing (36) is fixed to the roller support shaft (32) like the other bearing (37), and the roller support shaft ( The difference is that the roller support shaft (32) is sufficiently separated from the drive shaft (30) in the state where the roller support shaft (32) is assembled as shown in FIG. The distance between the roller support shaft (32) and the drive shaft (30) is at least the roller support shaft (32).
The engagement pins (36a) (36b) of the bearings (36) (37) move into the notch hole (50b) of the bearing support part (40) due to the movement of the bearings in the axial direction.
It is set to a distance sufficient to disengage (see Fig. 9).

In this embodiment, as shown in FIG. 8, the joint (50) is moved to the drive shaft (30) side in the same manner as in the above embodiment to separate the roller support shaft (32) from the drive shaft (30). After that, the bearings (36) (37) can be simultaneously removed from the bearing support portion (40) simply by moving the roller support shaft (32) to the drive shaft (30) side. Also, the roller support shaft (32) may be attached in the reverse order of this procedure.

Therefore, also in this embodiment, the roller support shaft (32) can be separated from the drive shaft (30) via the joint (50) between the side plates of the image forming apparatus main body as in the above embodiment. The roller support shaft (32) can be shortened. Also, bearings (36) (37) on the roller support shaft (32)
Since the roller support shaft (32) is fitted, it is not necessary to connect the bearings (36) (37) to the roller support shaft (32) under high fitting accuracy even when the roller support shaft (32) is attached. The same functions and effects as those of the above embodiment can be obtained. In this embodiment, the axial movement of at least one of the bearing (36) and the roller support shaft (32) may be restricted.

<Effects of the Invention> As described above, according to the paper feed roller mechanism of the image forming apparatus of the present invention, the roller support shaft can be shortened. Can be abutted against or caught in,
It is possible to easily attach and detach the roller support shaft in a narrow device.

Further, when the roller support shaft is attached, it is only necessary to attach the bearing to the bearing support portion, and it is not necessary to connect the bearing and the roller support shaft under a high fitting precision. There is a peculiar effect that it is possible to easily attach and detach the roller support shaft inside.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a paper feed roller mechanism according to the present invention, FIG. 2 is an exploded perspective view of a main part, and FIG. 3 is a side view of a main part showing a connection state of a roller support shaft with a drive shaft. 4 (A) and 4 (B) are explanatory perspective views showing a procedure for removing the roller support shaft, FIG. 5 is a plan sectional view showing a connection state of the roller support shaft with the drive shaft, and FIG. 6 is a roller support. FIG. 7 is a plan sectional view showing a state in which the shaft is separated from the drive shaft, FIG. 7 is a schematic view of the apparatus showing an applied state of the paper feed roller mechanism according to the invention, and FIG. 8 is another view of the paper feed roller mechanism according to the invention. FIG. 9 is a perspective view showing an embodiment, and FIG. 9 is a plan sectional view showing a state where the roller support shaft of FIG. 8 embodiment is connected to a drive shaft. (20) …… Feeding roller mechanism, (30) …… Drive shaft, (32) …… Roller support shaft, (34) …… Feeding roller, (36) (37) …… Bearing, (50)… …Joint.

Continuation of the front page (56) References JP-A-59-186841 (JP, A) JP-A-59-86521 (JP, A) JP-A-61-178334 (JP, A) Actual development Sho-53-75414 (JP , U) Actual opening 61-52646 (JP, U) Actual opening 63-41040 (JP, U)

Claims (1)

[Claims] 1. A drive shaft and a paper feed roller disposed in an intermediate portion,
A roller support shaft, one end of which is opposed to the shaft end of the drive shaft, a bearing fitted into both ends of the roller support shaft, and the bearing is disengaged by lateral movement of the bearing or the roller support shaft. A bearing support portion that is movably supported, the drive shaft and the roller support shaft are separably connected by movement in the axial direction, and movement of at least one of the bearing and the roller support shaft in the axial direction is restricted. A sheet feeding roller mechanism for an image forming apparatus, comprising a joint, and a connection point between the joint and the roller supporting shaft is set between side plates of the image forming apparatus main body.