JPH09202486A - Roller member for feeding/discharging paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the manufacture, and reduce the cost. SOLUTION: A friction member 3 is fitted to an outer circumference of a roller member 1, and the friction member 3 is integrated with a roller body 2 with two colors. The friction member 3 is made of thermoplastic elastomer and preferably formed >=2mm in thickness. The friction member 3 is preferably interposed integratedly between a plurality of branch parts provided on the outer circumference of the roller body 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding / discharging roller member used for supplying and discharging paper in, for example, a copying machine or a printer.

[0002]

2. Description of the Related Art FIG. 8 is a schematic structural layout showing an example of a paper feed mechanism used in an electronic copying machine. In FIG. 8, in this paper feeding mechanism, the paper 52 is stacked and set in the paper feeding cassette 50 and taken out by the hopping roller 51. Further, in front of the hopping roller 52, stacking feed prevention rollers 53, 54, conveyance rollers 55, 56, etc. are arranged. Of these, the overlap feed prevention roller 54 is a roller member incorporating a one-way clutch mechanism,
The paper 52 is rotated integrally with the drive shaft 57 in the direction opposite to the paper feeding direction, and the drive shaft 57 is rotated in the paper feeding direction.
It has a structure that can be freely rotated with respect to. Further, a friction rubber 58 is attached to the outer periphery of the overlap feeding prevention roller 54.

In this paper feed mechanism, when a paper feed command is issued, the hopping roller 51 contacts the paper 52 in the paper feed cassette 50 and rotates in the paper feed direction. At the same time, other than the overlap feed prevention roller 54, the overlap feed prevention roller 53 and the transport rollers 55 and 56 start to rotate in the sheet feeding direction. As a result, the paper 52 sent out by the hopping roller 51 is sent between the overlap-feed prevention rollers 53 and 54. When the paper 52 is fed between the overlap feed prevention rollers 53 and 54, the paper 52 is further conveyed to the conveyance rollers 55 and 56 by the overlap feed prevention rollers 53 and 54. When the sheet 52 is conveyed to a predetermined position in front of the conveying rollers 55, 56, this is detected by a sensor (not shown), and only the drive shaft 57 to which the overlap feed prevention roller 54 is attached is not in the sheet feeding direction. It is rotated to the other side. At this time, when a plurality of sheets of paper 52 are fed while being overlapped between the overlap feed prevention rollers 53 and 54, the upper side paper 52 and the lower side paper 52 are fed.
And a paper 52 on the lower side is fed back to the paper feeding cassette 51 side by the overlap feeding prevention roller 54.
Only the upper sheet 52 is directly conveyed to the conveyance rollers 55, 56 side. As a result, only one sheet of paper 52 is supplied. In addition, when the drive shaft 57 is driven for a predetermined time, the rotation of the drive shaft 57 stops. On the other hand, the paper 52 has already been conveyed by the transport rollers 55, 56.
And the transfer rollers 55, 5
It is conveyed to a predetermined position by 6 and. At this time, the overlap feed prevention roller 54 freely rotates in the paper feed direction in a form of guiding the supply of the paper 52.

FIG. 6 and FIG. 7 show a stack feed prevention roller 54.
FIG. 7 is a view showing the structure of (hereinafter, simply referred to as “roller member 54”) in more detail. FIG. 6 is a perspective view of the roller member 54 shown in a state of being attached to the drive shaft 57, and FIG. It is a figure. 6 and 7, the roller member 54
Is a resin roller body 61 on the outer periphery, friction rubber 58 mounted on the outer periphery of the roller body 61, and the roller body 6
1 has a one-way clutch mechanism 62 incorporated at one end thereof, and the drive shaft 5 is connected via the one-way clutch mechanism 62.
It has been attached to 7. That is, the roller body 61 and the drive shaft 57 can freely rotate, and the one-way clutch mechanism 62 and the drive shaft 57 are fixed. The one-way clutch mechanism 62 allows the roller body 61 to freely rotate with respect to the drive shaft 57 when the roller body 61 rotates in one direction, and allows the roller body 61 to rotate in the opposite direction. It is restricted so that it cannot rotate unless it is integrated with 57.

Next, the friction rubber 5 against the roller body 61
The mounting structure of No. 8 will be described. The friction rubber 58 is formed in a tubular shape, and the roller body 61 has a recess 63 in which the friction rubber 58 is mounted. When the friction rubber 58 is attached, the roller body 61 is pushed (press fit) while expanding the opening of the friction rubber 58, and the friction rubber 5 is inserted into the recess 63.
The method of mounting 8 is taken.

[0006]

As described above, in the conventional roller member 54, the friction rubber 58 is attached to the roller body 61.
It has a structure in which is attached by pressing. Therefore, the larger or longer the friction rubber 58 is, the more difficult it is to assemble, which is one of the reasons for increasing the cost. Also,
Even if the friction rubber 58 of this type is attached to the roller body 61 via an adhesive or the like, it is likely to be deformed due to thermal influence due to long-term use or the like and the integration with the roller body 61 will not be maintained. There is also the fear that it will not be rotated.

The present invention has been made in view of the above problems, and an object thereof is to provide a sheet feeding / discharging roller member having a structure that simplifies the manufacturing and reduces the cost. Further, other objects will be clarified sequentially in the contents described below.

[0008]

In order to achieve the above object, the present invention is a roller member for paper feeding and discharging, which is incorporated in a copying machine or the like and in which a friction material that comes into contact with paper is provided on the outer periphery of the roller body. In the above, the friction material and the roller body are integrally formed by two-color molding.

Since the paper feeding / discharging roller member of the present invention is formed by two-color molding of the friction material and the roller body, the work of assembling the friction material and the roller body later becomes unnecessary. In two-color molding, it is possible to sufficiently enhance the joint strength between the friction material and the roller body by devising the shape of the joint between the friction material and the roller body. It is possible to easily secure the same quality as the friction material made of rubber.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. 1 to 5 show an example of one embodiment of the roller member according to the present invention.
It will be described as a case where the roller member 54 shown in FIG.
Therefore, FIG. 1 is a vertical sectional side view of the roller member shown in a state of being attached to the drive shaft 57, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a sectional view taken along the line BB of FIG. Fig. 4 and Fig. 1
5 is a sectional view taken along the line CC of FIG. 5, and FIG. 5 is a perspective view of the roller member attached to the drive shaft 57.

1 to 5, the roller member 1 is
The drive shaft is roughly composed of a resin roller body 2, a resin friction material 3 provided on the outer periphery of the roller body 2, and a one-way clutch mechanism 4 arranged at one end of the roller body 2. It is used by attaching it to 57. The roller body 2 and the friction material 3 are formed by two-color molding.

More specifically, the roller body 2 is made of polyacetal (POM) having excellent chemical resistance and mechanical properties.
Is used to form a substantially cylindrical shape, and a through hole having a size that allows the drive shaft 57 to freely rotate is provided in the center. Further, in the injection molding, a plurality of branch portions 5 (four in the circumferential direction at intervals of 90 degrees in the present embodiment) are shown in FIG. 4 corresponding to the portions where the friction material 3 is two-color molded later. As described above, it is radially provided and is integrally provided at a plurality of locations along the axis (in this embodiment, 10 locations at substantially the same intervals in the axial direction as shown in FIG. 1). In addition, a pair of elastic pieces 6 which are elastically deformable in the inner and outer peripheral directions are formed on the inner surface of the roller body 2 on one end side, and the engaging protrusions 7 are formed on the facing surfaces on the tip side of each elastic piece 6. Is provided. In addition, the engaging protrusion 7
It engages with a positioning groove 8 formed around the outer surface of the drive shaft 57, and the engagement regulates the position in the thrust direction.

On the other hand, a case portion 18 for a one-way clutch mechanism is integrally formed on the inner surface on the other end side of the roller body 2. The case portion 18 is formed as a circular space having one end opened, and an inner gear 9 is formed on the inner surface thereof. Further, in the case portion 18, three gears 10, which are held by a separate gear holder 11, are arranged at equal intervals, and each gear 10 is meshed with the inner gear 9. The gear holder 11 is rotatably attached to the roller body 2 in the case portion 18, and integrally has a cylindrical portion 12 at the center thereof, through which the drive shaft 57 is passed. In addition, a slit-shaped cut 13 is formed in a part of the cylindrical portion 12, and a locking pin 14 that vertically penetrates the drive shaft 57 is engaged with the cut 13. Therefore, the gear holder 11 has the engagement pin 1
Through the engagement between 4 and the notch 13, the drive shaft 57 always rotates integrally with the drive shaft 57. Further, the gear holder 11 and the gear 10
In the meantime, when the drive shaft 57 is rotated in the locking direction shown by the arrow in FIG. 3, the gear 10 is engaged with a part of the gear holder 11 to stop the rotation, and the gear holder 11 and the case portion 18 Lock the space between the gear holder 1 with this lock
1 and the case portion 18, that is, the roller body 2 and the drive shaft 57.
It can be in a locked state in which and rotate together. On the contrary, when the gear 10 rotates in the direction opposite to the arrow, the gear 10 is freely rotated without being caught in the gear holder 11, and the gear holder 11 and the case portion 1 are rotated.
8, that is, a structure in which the roller body 2 and the drive shaft 57 are freely rotated to be in a free state, that is, a one-way clutch mechanism. The structure of the one-way clutch mechanism itself is well known.

Next, the friction material 3 is formed of a thermoplastic elastomer (TPE) having flexibility similar to that of the vulcanized rubber. This friction material 3 is the roller body 2 that has already been molded.
Is set in a molding die (not shown) in a state where the gear 10 and the gear holder 11 are not assembled, and two-color molding is performed in this state. Then, the friction material 3 is formed in a state of being integrated with the roller body 2. In this two-color molding,
Branches 5 are provided on the outer circumference of the roller body 2 and are provided at substantially equal intervals along the axis. When the molten TP0 resin stock solution is supplied from the corresponding cylinder into the molding die, It also flows into the groove formed between the branches 5 and is firmly integrated with the outer periphery of the roller body 2. In other words, the outer peripheral surface area of the roller body 2 is larger than the outer peripheral surface area of the conventional roller body due to the presence of the plurality of branch portions 5 (or the plurality of groove portions formed between the branch portions 5) provided in the axial direction. The outer surface area is several times larger. Therefore, the joint portion of the two-color molded friction material 3 is correspondingly enlarged, and the molded friction material 3 is more strongly and integrally bonded to the roller body 2. The hardness of the friction member 3 is about 80 in Shore hardness, and has the required rubber elasticity. In this case, the hardness of the friction material 3 also changes depending on its thickness. The thickness of the friction material 3 is preferably set to at least 2 mm or more from various tests.

Therefore, according to the roller member 1 of the present embodiment, the friction material 3 and the roller body 2 are two-color molded and integrally formed, so that the work of assembling the friction material 3 and the roller body 2 later becomes unnecessary. Become. Specifically, in the assembling process, the work of assembling the gear 10 and the gear holder 11 in the case portion 18 may be performed, and the number of assembling steps can be reduced. The friction material 3 is firmly joined to the roller body 2 by a plurality of branches 5 (or a plurality of grooves formed between the branches 5) and has a thickness of 2 m.
By setting m or more, the same quality as conventional friction rubber can be maintained for a long period of time.

In the above embodiment, the case where the present invention is applied to the overlap feed prevention roller in the paper feed mechanism has been described, but the present invention is not limited to this, and a general roller member arranged in all paths from supply to paper discharge, That is, it can be applied to a paper feeding / discharging roller member.

[0017]

As described above, according to the sheet feeding / discharging roller member of the present invention, it is possible to eliminate the work of assembling the friction material and the roller body, which is required in the conventional structure, so that the number of assembling work steps is reduced. The cost can be reduced and the product can be provided at a low price. The joining strength, elasticity, etc. of the friction material can be easily improved to the same level as or more than the conventional one by satisfying predetermined conditions, as is clear from the embodiment.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing a state in which a roller member of the present invention is attached to a drive shaft.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along the line BB of FIG.

4 is a cross-sectional view taken along the line CC of FIG.

FIG. 5 is a perspective view showing the roller member of the present invention attached to a drive shaft.

FIG. 6 is a perspective view of a conventional roller member.

FIG. 7 is a vertical sectional side view of a conventional roller member.

FIG. 8 is a schematic configuration layout diagram showing an example of a conventional paper feed mechanism.

[Explanation of symbols]

 1 Roller Member 2 Roller Main Body 3 Friction Material 4 One-Way Clutch Mechanism 5 Branch 57 Drive Shaft

Claims (4)

[Claims] 1. A paper feeding / discharging roller member incorporated in a copying machine or the like, wherein a friction material for contacting paper is provided on the outer circumference of a roller body, wherein the friction material and the roller body are formed by two-color molding. A sheet feeding / discharging roller member, which is formed integrally. 2. The paper feeding / discharging roller member according to claim 1, wherein the friction material is made of a thermoplastic elastomer and has a thickness of 2 mm or more. 3. The sheet feeding / discharging roller member according to claim 1, wherein the friction material is integrally interposed between a plurality of branch portions provided on the outer periphery of the roller body. 4. The sheet feeding / discharging roller member according to claim 1, wherein a one-way clutch mechanism is provided on one end side of the roller body, and the roller body is attached to a drive shaft via the one-way clutch mechanism.