JPH0893857A - Rotational gear using belt body - Google Patents

Abstract

PURPOSE: To provide a gear using a belt body inexpensive, highly precise and capable of transmitting rotary motion. CONSTITUTION: Rotation of a drive pulley is transmitted to a driven pulley through a belt body. Hereby, a back surface 5b of the belt body 5 is sufficiently higher in a sliding property than a belt body internal surface 5a. Additionally, as a belt presser 6 to give constant tensile force to the belt body 5 is columnar, it is supported impossible to rotate, and its outer peripheral surface is sufficiently high in the sliding property.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary transmission device using a belt body, which is used for transmitting relatively low torque and rotation with high accuracy in an internal mechanical portion such as OA equipment and electric equipment.

[0002]

2. Description of the Related Art Many conventional rotary transmission devices of this type have a construction as shown in FIG.

An output from a motor or the like, which is a drive source (not shown), is first transmitted to the drive pulley 1, and then rotation and torque are transmitted to the driven pulley 2 via the belt body 9.
Then, the driven pulley 2 imparts a desired rotation to the driven body whose support shaft 4 is illustrated, for example, the shaft portion of the image carrier or the shaft portion of the paper conveying device in the electrophotographic copying machine, A rotation transmission action is realized.

In this case, it is necessary to keep the tension of the belt body 9 constant so that the belt body 9 does not come off from the pulleys 1 and 2, or the winding angle of the belt body 9 around the pulleys 1 and 2 is desired. Idler pulley 1
It is common to prepare 0.

Of these pulleys 1, 2 and 10, the drive pulley 1 and the driven pulley 2 are non-rotatably supported by the support shaft 3 and the support shaft 4 for transmitting torque, and the idler pulley 10 is supported. The shaft 11 is rotatably supported by the shaft 11.

The following two points are particularly important for accurately transmitting rotation in the rotation transmission device using the belt member 9.

1. The center of rotation of the rotating body and the center of inertia coincide with each other, and the shape when rotated is rotationally symmetric.

2. There is little load fluctuation due to rotation.

[0009]

However, the rotary transmission device of the prior art has the following drawbacks.

[0010] 1. When torque and rotation are transmitted using an idler pulley in order to apply a certain tension to the belt body or to set the winding angle of the belt body around the pulley, the friction coefficient on the back surface of the belt body is generally large. ,
The idler pulley must be rotatable. For that purpose, the idler pulley must be supported by the fitting shaft in a state where there is a gap in the support shaft, and a play is generated between the idler pulley and the support shaft. Since the idler pulley rotates in this play, a. An unstable state occurs in which the rotating idler pulley contacts or does not contact the support shaft, and as a result, the frictional resistance between the idler pulley and the shaft fluctuates.

B. The center of inertia of the idler pulley is eccentric with respect to the center of rotation, and the rotation of the idler pulley is not rotationally symmetrical with respect to the center of rotation.

Except for the drawbacks of 2.1, in order to realize smooth and highly accurate transmission of rotary motion by the idler pulley, a rotary support member such as a bearing or an oil-impregnated sintered body is provided between the idler pulley and the support shaft. When the sliding member is provided, the number of constituent parts of the component increases, so that the component cost and the assembly cost increase.

An object of the present invention is to overcome the above-mentioned drawbacks and to provide a rotary transmission device using a belt body which can transmit rotary motion with high precision by a simple structure.

[0014]

A rotary transmission device using a belt body of the present invention is a rotary transmission device using a belt having a drive pulley, a driven pulley, a belt body and a belt retainer. Is sufficiently slippery than the inner surface of the belt, the portion of the belt presser that comes into contact with the back surface of the belt body is smooth, and the belt presser is non-rotatably supported.

As a method of reducing the friction coefficient of the back surface of the belt body, the back surface portion of the belt body may be adjusted by blending a composition material or another method, or a member having a low friction coefficient may be attached or a member having a low friction coefficient may be bonded. The material may be coated.

If the back surface of the belt body has a low coefficient of friction,
Any type of so-called flat belt, timing belt, V-belt, etc. may be used.

A method for reducing the friction coefficient of the belt retainer is as follows.
A material having a low coefficient of friction may be used, a member having a low coefficient of friction may be attached to a sliding contact portion with the belt body, or a material having a low coefficient of friction may be coated.

The shape of the belt retainer may be a cylindrical body or any other shape as long as the sliding contact surface with the belt body is smooth, and a part of the support member of the plate-shaped rotation transmission mechanism is deformed. You may shape.

The belt retainer may be fixed to the support member of the rotation transmitting mechanism, or the fixing position may be adjustable in order to adjust the tension of the belt body and the pulley winding angle of the belt body. .

[0020]

Since the belt retainer does not rotate, there is no play caused by the rotation of the belt retainer as in the conventional example, and highly accurate rotation can be transmitted. Also, since the belt retainer does not rotate,
The number of parts for the belt retainer is small and reliability is improved.

[0021]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram of a rotary transmission device using a belt body according to a first embodiment of the present invention. The same reference numerals as in FIG. 5 indicate the same members.

In this embodiment, the belt body 5 having a lower back surface friction coefficient is used, the tension of the belt body 5 is kept constant so that the belt body 5 does not come off from the pulleys 1 and 2, and further, the belt body 5 In order to set a desired winding angle around the pulleys 1 and 2, a cylindrical belt presser 6 having an outer peripheral surface having a low friction coefficient is non-rotatably arranged on the moving path of the belt body 5.

As a method of lowering the friction coefficient of the back surface of the belt body 5, there are methods such as polishing or tanning the back surface of the belt, or forming a layer in which fluorine resin powder is bound with a synthetic resin binder on the back surface. . Further, as the cylinder axis having a low friction coefficient on the outer peripheral surface, there is, for example, SUS420 material used for a tape guide post of a VTR or the like.

As described above, in this embodiment, the tension of the belt body 5 is kept constant by the non-rotatable cylindrical shaft 6 and the winding angle of the belt body 5 around the pulleys 1 and 2 is desired. Unlike the conventional example, there is no play in the rotating system, and highly accurate rotation transmission can be realized at low cost.

FIGS. 2 (1) and 2 (2) are a front view and a side view of a belt pressing portion of a rotary transmission device using a belt body according to a second embodiment of the present invention.

In this embodiment, in place of the belt retainer 6 in the first embodiment, the belt retainer having the cylindrical portion 7a having the low friction coefficient and the flange portions 7b and 7c instead of the belt retainer 6 is provided. The belt retainer 7 is prevented from coming off during the rotational movement.

FIGS. 3 (1) and 3 (2) are a front view and a side view of a belt pressing portion of a rotary transmission device using a belt body according to a third embodiment of the present invention.

This embodiment is different from the first embodiment in that, instead of the belt retainer 6, the plate-shaped support member 8a having a low friction coefficient on the surface for fixing and holding the support shafts of the drive pulley and the driven pulley is used. The cost is reduced by providing the belt retainer 8b formed by deforming a part thereof.

FIGS. 4 (1) and 4 (2) are a front view and a side view of a belt pressing portion of a rotation transmission device using a belt body according to a fourth embodiment of the present invention.

In the present embodiment, the friction coefficient with the belt body 5 is further reduced by disposing the member 8c having high slidability on the upper surface of the belt retainer 8b in the third embodiment.

[0032]

As described above, according to the present invention, the back surface of the belt body has a sufficiently higher slipperiness than the inner surface of the belt body, and the portion of the belt presser which comes into contact with the back surface of the belt body is smooth and the belt presser body is pressed. The non-rotatable support has the following effects.

1. Since there is no play during rotation in the belt retainer, rotation and torque can be accurately transmitted.

2. Since the number of belt pressing parts is small, the mechanism can be constructed at low cost.

3. By deforming a part of the support member of the plate-shaped rotation transmission mechanism to form the belt retainer, the manufacturing and assembly costs can be reduced.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a rotation transmission device using a belt body according to a first embodiment of the present invention.

FIG. 2 is a front view (1) and a side view (2) of a belt holder of a rotary transmission using a belt body according to a second embodiment of the present invention.

FIG. 3 is a front view (1) and a side view (2) of a belt retainer of a rotation transmission device using a belt body according to a third embodiment of the present invention.

FIG. 4 is a front view (1) and a side view (2) of a belt retainer of a rotation transmission device using a belt body according to a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional example.

[Explanation of symbols]

 1 Drive Pulley 2 Driven Pulleys 3 and 4 Support Shaft 5 Belt Body 5a Inner Surface 5b Rear Surface 6 Belt Presser 7 Belt Presser 7a Cylindrical Part 7b, 7c Flange 8 Belt Presser 8a Pulley Support Shaft Support Member 8b Belt Presser Body 8c Sliding Member 9 Belt Body 10 Idler pulley 11 Support shaft

Claims (7)

[Claims] 1. A drive pulley which is rotationally driven, a driven pulley, a belt body which is stretched between the drive pulley and the driven pulley and which transmits torque and rotation to the driven pulley, and a belt body of the belt body. In a rotary transmission device using a belt, which has a belt presser for maintaining a constant tension and further for making a winding angle of the belt body around the pulley, a back surface of the belt body is a belt inner surface. It has a sufficiently higher slipperiness than that of the belt holder, and the portion of the belt holder that comes into contact with the back surface of the belt body is smooth, and the belt holder is non-rotatably supported. The rotating transmission that was used. 2. The rotation transmission device using a belt body according to claim 1, wherein a portion of the belt retainer that comes into contact with the back surface of the belt body has sufficiently high slipperiness. 3. The rotation transmission device using a belt body according to claim 1, wherein the belt retainer is a columnar body in which the belt body is in sliding contact with an outer peripheral surface thereof. 4. The rotation transmission device using a belt body according to claim 1, wherein the belt retainer comprises a columnar portion on the outer peripheral surface of which the belt body slidably contacts, and flange portions provided at both ends thereof. 5. The rotation transmission device using a belt body according to claim 1, wherein the position of the belt retainer is adjustable. 6. The belt body according to claim 1, wherein the belt retainer is formed by deforming a part of a plate-shaped member that holds the support shafts of the drive pulley and the driven pulley in a fixed manner. The rotating transmission that was used. 7. The rotation transmission device using a belt body according to claim 5, wherein a member having a surface having a sufficiently high slidability is stretched on a portion of the belt retainer which is in sliding contact with the back surface of the belt body.