JP2644242B2 - Rubber cushioning member - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for a driving member such as a driving member for an optical system of an image forming apparatus, and more specifically, is disposed between a driving member and a driven member and used as a power transmission member. The present invention relates to a rubber cushion member to be used.

2. Description of the Related Art An elastic material is used to prevent an impact from being transmitted from a driving member to a driven member when a buffer occurs when a driving direction is changed, such as a reciprocating optical system driving device of an image forming apparatus such as a copying machine. It is widely known to use a buffer member made of As such a cushioning member, a rubber damper, particularly, disposed between the driving member and the driven member, is formed on the engaged portion and the driven member to be engaged with the engaging portion formed on the driving member. Further, a rubber cushioning member having another engaged portion to be engaged with another engaging portion and transmitting the rotation of the driving member to the driven member and the driven member is often used. In many cases, a pin is used as the engaging portion, and a hole into which the pin is inserted is used as the engaged portion. In the rubber damper, as shown in FIG. 10, each time an impact is applied, the elastic member repeatedly expands and contracts, and by repeating the expansion and contraction, the hole 53 of the rubber cushioning member 52 with which the pin 51 of the driving member engages and the driven member. As in the hole 53 in which the pin 54 engages, it gradually deforms and cracks from the portion where the force is concentrated, breaks and breaks, the effect of the damper is lost, and the life is shortened. Therefore, the conventional rubber cushioning member has a problem in durability.

In particular, as shown in FIG. 11, when the rubber cushioning member 52 transmits the rotation to the driven member by the rotation of the driving member, the pins 51 and 54 as the engaging portions of the driving member or the driven member and the rubber cushioning member 52 When the inner surface of the rubber cushioning member 52 comes into direct contact with the outer peripheral surface of the boss member 55 of the driving member or the driven member at the same time as transmission by the engagement of the hole 53 as the engaged portion of The buffer member 52 cannot be deformed smoothly, and the damper effect is reduced.

When the boss 55 and the inner peripheral surface of the cushioning member 52 come into contact with each other at a part indicated by A, only a part of the engaged part, that is, the hole 53 ′ which is a part of the engaging part is caused by friction of the contact part. The power is transmitted between the pin 51 of the driving member or the pin 54 of the driven member while greatly deforming. This concentrates the force on some of the holes 53 'to accelerate the breaking and shorten the life.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the conventional rubber cushioning member and to provide a rubber cushioning member having durability and a long life.

Configuration In order to achieve the above object, the present invention is configured such that a rubber hardness of a region around an engaged portion of a rubber cushioning member engaged with each engaging portion is formed higher than other regions of the member, An inner diameter surface of the cushioning member is supported by a collar, and the collar is rotatably supported by a boss of either the driving member or the driven member.

The configuration and operation of the present invention will be described in detail based on an embodiment shown in the drawings.

1 and 2, a rubber cushioning member 1 according to the present invention is formed in a substantially disk shape, and a hole 2 as an engaged portion is formed at an appropriate position. A region 8 around the hole 2, that is, an annular peripheral region with which the engaging member of the driving member is directly engaged is formed to have a higher rubber hardness than other regions.

The rubber cushioning member 1 is disposed, for example, between the driving member 4 and the driven member 5 as shown in FIG. 3, and the engaging portion 6 of the driving member 4 shown in FIG. 3 and FIG. Hole 2
Is inserted and engaged with the engaged portion. 3 and 5
A driven member 5 shown in the figure, for example, an engaging portion 7 provided on a gear, for example, a pin is inserted and engaged with an engaged portion formed of the hole 2. A collar 3 is fitted into the inner diameter surface of the rubber cushioning member 1, and
1a is supported by the collar 3. The collar 3 is the driving member 4
And one of the driven members 5, the driven member 5 in the illustrated example.
Is rotatably fitted to the outer periphery of the boss 5a.

With this structure, it is possible to avoid that the buffer member is partially in contact with the boss portion and the part to be engaged is deformed.

In order to strengthen the engaged portion, the area 8 around the hole 2, that is, for example, an annular area where the engagement member of the drive member is directly engaged is formed to have a higher rubber hardness than other areas. Pin 6
Contacts the annular region 8 around the hole 2 where the rubber hardness is large, and the rotation of the driving member 4 is transmitted to the buffer member 1 through the engagement between the pin 6 and the hole 2. Further, the pin 7 of the driven member 5 directly contacts the annular region 8 having a large rubber hardness of the hole 2 of the rubber buffer member 1, and the rotation of the rubber buffer member 1 is driven through the engagement of the hole 2 and the pin 7. It is transmitted to the member 5.

When there is no fluctuation in the rotation of the driving member 4, the driven member 5 is also uniformly rotated without fluctuation. When the load on the driving member 4 fluctuates and rotation unevenness occurs, the rubber cushioning member 1 is deformed because most of the rubber cushioning member 1, that is, a portion other than the annular region is formed as a rubber portion having low rubber hardness. In addition, uneven rotation due to a fluctuating load is absorbed, and fluctuations in rotation and load are hardly transmitted to the driven member 5.

The rubber buffer member 1 itself repeatedly expands and contracts due to the fluctuation of the load. However, at the portion where the force is concentrated, that is, at the contact portion between the pin and the annular region 8, the rubber hardness of the annular region is increased, so that the breaking strength increases. Cracks are less likely to occur.

As a device using the rubber cushioning member, there is, for example, a driving device of a copying machine as shown in FIGS. 6 and 7. 6 and 7, the rotation of the first gear 12 attached to the output shaft of the motor 11 is transmitted to the photoconductor driving gear 14 via the second gear 13. A photoconductor drum (not shown) is rotated by the photoconductor drive gear 14.

The rotation of the photoconductor drive gear 14 is transmitted to the input gear 17 of the forward / reverse rotation drive unit 16 via the third gear 15.

The input gear 17 is rotatably supported by a first output shaft 18 rotatably supported by a casing 19.
Meshes with an intermediate gear 21 rotatably supported by a second output shaft 20 rotatably supported by the motor.

The input gear 17 is connected to a first output shaft 18 by a first electromagnetic clutch 22.
The connection with is turned ON and OFF. A first output gear 23 is fixed to the first output shaft 18.

The intermediate gear 21 is connected to the second output shaft 20 by the second electromagnetic clutch 24.
The connection with is turned ON and OFF. A drive member 4 shown in FIG. 3 is fixed to the second output shaft 20, a second output gear 5 as a driven member is rotatably supported, and a rubber is provided between the drive member 4 and the second output gear 5. They are connected by a buffer member 1.

When the first electromagnetic clutch 22 is turned on, the first output gear 23 is rotated counterclockwise in FIG. 6, and the second electromagnetic clutch 24 is turned on.
Then, the second output gear 5 is rotated clockwise in FIG. 6 via the driving member 4 and the rubber cushioning member 1.

The first output gear 23 and the second output gear 5 are connected to pulleys 25, respectively.
Gears fixed or integral with the gear
When the electromagnetic clutch 22 is ON, the second electromagnetic clutch 24 is OFF
The pulley 25 is rotated clockwise in FIG. 6 by the first output shaft 23, and drives the optical system drive wire 26 wound around the pulley 25 rightward in the figure to move the scanner or the platen forward. . Next, when the first electromagnetic clutch 22 is turned off and the second electromagnetic clutch 24 is turned on, the drive transmission is changed from the first output gear 23 to the second output gear 5, the pulley 25 is reversed in the counterclockwise direction, and the optical system The drive wire 26 moves backward in the figure.

At the time of reversal from the forward movement to the backward movement, the fluctuation of the driving load is transmitted to the photoconductor drive gear 14 via the gear train, and the rotation speed of the photoconductor is momentarily reduced. At this time, the image is blurred if the transfer process is performed. However, by interposing the buffer member 1, the rubber buffer member 1 absorbs the fluctuation of the load at the time of reversal, that is, the drive shock, and softens the load. be able to. As a result, it is possible to reduce the rotation unevenness of the photoreceptor and make the image blur less noticeable.

In the rubber cushioning member 1, the pin 6 of the driving member 4 and the pin 7 of the second output gear 5 as a driven member are in contact with the annular region 8 having a high rubber hardness. Is hardly deformed, can withstand a sufficient concentration force, and can absorb load fluctuation itself by deformation of a region having a low rubber hardness outside the annular region. The rubber buffer member 1 itself deforms and absorbs shocks or the like in response to a load change. However, the annular region around the hole 2 where the pins 6 and 7 as the engaging members are engaged is difficult to deform. Breaking can be prevented.

According to the present invention, the collar 27 is arranged between the inner peripheral surface of the rubber cushioning member 1 and the outer peripheral surface of the boss member 5a of the driven member as shown in FIGS. The problem caused by the contact between the boss portion and the inner peripheral surface of the cushioning member can be solved. That is, the eighth
By providing the collar 27 as shown in the figure, the rubber cushioning member 1 and the boss member 5a do not directly contact each other. Since there is no local frictional contact between them, a force is evenly applied between the pins 6 and 7 and each of the holes 2, and it is possible to avoid locally deforming the rubber cushioning member 1. If the local deformation occurs, the collar 27 rotates, so that the local deformation is eventually eliminated. By making the annular region 8 around the hole 2 higher in rubber hardness than the other regions, the hole 2 is hardly deformed as shown in FIG. become.

The rubber cushioning member 1 has a hole 2 as an engagement of the pins 6 and 7.
Depending on the arrangement, only the hole 2 can be formed as shown in the figure, although it is not particularly used as the engaged portion, but considering the balance.

Advantageous Effects According to the present invention, the rubber cushioning member is formed into two types of rubber hardness in the directly engaged region of the engaged portion where the engaging portion of the driving member and the driven member engages, higher in rubber hardness than the peripheral region. As a result, the engaged portion is reinforced and the life of the rubber cushioning member is extended. On the other hand, the damper effect is effectively secured, and stable performance over time can be obtained. In addition, since the inner diameter surface of the rubber cushioning member is supported by the collar, and the collar is rotatably supported by one of the bosses of the driving member and the driven member, the rubber cushioning member partially contacts the boss. As a result, it is possible to avoid a situation in which some engaged portions are deformed. As a result, the replacement frequency of the rubber cushioning member is reduced.

[Brief description of the drawings]

1 is a front view of a cushioning member according to the present invention, FIG. 2 is a side view, FIG. 3 is a cross-sectional view showing a state before assembling the cushioning member, a driving member and a driven member, and FIG. FIG. 5 is a left side view of the driven member of FIG. 3, FIG. 5 is a left side view of the driven member of FIG.
The figure is a schematic front view of an example of a driving device using the cushioning member,
7 is a sectional view taken along the line VII-VII of FIG. 6, FIG. 8 is a front view of another example of the present invention in a modified state, and FIG. FIG. 10 is an explanatory view of a state at the time of load when the rubber hardness of the portion is reinforced, FIG. 10 is a view showing deformation of the conventional buffer member at the time of load, and FIG. FIG. 9 is a diagram illustrating deformation when the boss contacts the boss. DESCRIPTION OF SYMBOLS 1 ... Rubber cushioning member, 2 ... Engagement part 3 ... Collar, 4 ... Driving member 5 ... Engagement part, 6, 7 ... Engagement part

Claims (1)

(57) [Claims] A first member disposed between the driving member and the driven member;
Rubber having an engaged portion engaged with an engaging portion provided on a driving member and an engaged portion engaged with an engaging portion provided on a driven member, and transmitting rotation of the driving member to a driven member. The cushioning member of the present invention, wherein the rubber hardness of the region around the engaged portion of the buffering member engaging with each engaging portion is formed higher than the other region of the member, and the inner diameter surface of the buffering member is A rubber cushioning member supported by a collar, wherein the collar is rotatably supported by one of bosses of a driving member and a driven member.