JPH0594558U - Friction drive - Google Patents

Abstract

(57) [Abstract] [Purpose] In a friction drive device, the outer peripheral surfaces of the drive roller and the backup roller are brought into uniform line contact with the slider friction surface. [Structure] A drive roller 1 and a backup roller 2 are arranged in parallel, and a slider 3 is sandwiched at a right angle between them. The support shaft 5 of the backup roller 2 is attached at a right angle to a rotary shaft 10 parallel to the slider 3 via an elastic parallel displacement mechanism 6 such as a parallel spring. Backup roller 2
Rotates about the rotation axis 10 and moves in parallel to the elastic parallel displacement mechanism by 6 to make uniform line contact with the friction surface of the slider 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a friction drive device. More specifically, the present invention relates to a friction drive device that converts a rotational movement of a drive roller into a linear movement of a slider by frictional force.

[0002]

[Background technology]

 3A and 3B are a front view and a side view, respectively, of a conventional friction drive device C, which is partially broken. In this friction drive device C, a backup roller 32 is rotatably attached to a support shaft 35 via a bearing 34, and a slider 33 is provided between the drive roller 31 and the backup roller 32 arranged in parallel. It is sandwiched at a right angle, and the outer peripheral surface of the drive roller 31 and the friction surface 33a of the slider 33 are in line contact, and the outer peripheral surface of the backup roller 32 and the friction surface 33b of the slider 33 are also in line contact.

When the drive roller 31 is rotationally driven, however, the rotational motion of the drive roller 31 can be converted into the linear motion of the slider 33 by friction, and the slider 33 can be displaced in the longitudinal direction. it can.

[0004]

[Problems to be solved by the device]

 However, in the conventional friction drive device C, when the parallelism between the friction surfaces 33a and 33b of the slider 33 is poor [FIG. 4 (a)] or when the drive roller 31 is inclined [FIG. 4 (b)]. )], There is a problem that the outer peripheral surface of the backup roller 32 and the friction surface 33b of the slider 33 are in point contact with each other, and the contact portion is abraded so much that the back up roller 32 and the slider 33 are worn out.

Further, when the backup roller 32 and the slider 33 are in point contact with each other, the frictional force between the drive roller 31 and the slider 33 becomes non-uniform, and the slider 33 cannot be stably displaced. was there.

The present invention has been made in view of the above-mentioned drawbacks of the conventional example, and an object of the present invention is to uniformly make line contact between the outer peripheral surfaces of the drive roller and the backup roller and the friction surface of the slider. To provide a friction drive device.

[0007]

[Means for Solving the Problems]

 In the friction drive device of the present invention, a slider is sandwiched between a drive roller and a backup roller, which are arranged substantially parallel to each other, and the frictional motion between the drive roller and the slider converts the rotational motion of the drive roller into a linear motion of the slider. In the friction drive device, the base end of an elastic parallel displacement mechanism whose tip is elastically displaced in parallel in the lateral direction is supported rotatably around the direction parallel to the slider movement direction. A support portion that rotatably holds the backup roller is provided at the tip of the elastic parallel displacement mechanism.

[0008]

[Action]

 In the friction drive device of the present invention, the base end of the elastic horizontal displacement mechanism holding the backup roller is rotatable about the direction substantially parallel to the moving direction of the slider. Even if the friction surface is inclined, the backup roller is rotated so that the outer peripheral surface is parallel to the friction surface of the slider by the rotation of the base end portion of the elastic parallel displacement mechanism. Further, since the backup roller is held by the elastic parallel displacement mechanism, the backup roller moves in parallel so as to ride on the friction surface of the slider, makes linear contact with the friction surface of the slider, and makes uniform contact. ..

Therefore, even if the parallelism between the friction surfaces facing each other of the slider is poor or the drive roller is inclined, the support portion of the backup roller rotates and moves in parallel, so that the backup roller is moved. Make uniform line contact with the slider. Therefore, even in such a case, it is possible to prevent the slider or the like from being abraded, worn out, or unstable in displacement due to uneven contact.

Further, the backup roller is designed to rotate and move in parallel only in a plane perpendicular to the slider, and is not inclined with respect to the moving direction of the slider, so that the slider is always stably displaced. be able to.

[0011]

【Example】

 1 (a) and 1 (b) are a partially broken front view and a side view of a friction drive device A according to an embodiment of the present invention. In this friction drive device A, a slider 3 is sandwiched at a right angle between a drive roller 1 and a backup roller 2 which are arranged substantially parallel to each other.

The cylindrical backup roller 2 is rotatably attached to the tip of the support shaft 5 via a bearing 4, and the base end of the support shaft 5 is held at the tip of the elastic parallel displacement mechanism 6. Has been done. The base end of the elastic parallel displacement mechanism 6 is attached to the tip of the rotary shaft 10 arranged in parallel with the slider 3, and the base end of the rotary shaft 10 is freely rotatable to the bearing portion 12 via the bearing 11. Held in. As a result, the support shaft 5 of the backup roller 2 is arranged at a right angle to the rotary shaft 10. In the illustrated example, the elastic horizontal displacement mechanism is parallel to the rotation shaft 10 and orthogonal to the support shaft 5, but may be disposed orthogonal to the rotation shaft 10 and parallel to the support shaft 5.

Therefore, the backup roller 2 is rotated around the rotation shaft 10 by rotating the rotation shaft 10 and can be rotated in a plane orthogonal to the slider 3.

In the elastic parallel displacement mechanism 6, for example, two leaf springs 7, 7 having the same length are arranged in parallel with the leaf spring surfaces facing each other, and both ends of the leaf springs 7, 7 are provided with two support blocks. The support blocks 8 on the front end side are displaced so as to move in parallel in the lateral direction by the elastic bending of the leaf springs 7, 7. The base end portion of the backup roller 2 is fixed to the support block 8 on the tip end side, and the support block 9 on the base end side is fixed to the tip end portion of the rotating shaft 10.

Then, the rotation of the rotating shaft 10 causes the angle of the backup roller 2 to be inclined parallel to the friction surface 3b of the slider 3, and the elastic parallel displacement mechanism 6 causes the backup roller 2 to ride on the friction surface 3b of the slider 3. Thus, the back-up roller 2 makes line contact with the friction surface 3b of the slider 3. Moreover, since the elastic parallel displacement mechanism 6 controls the position of the backup roller 2 in parallel with the friction surface 3b of the slider 3, the outer peripheral surface of the backup roller 2 is evenly pressed against the friction surface 3b of the slider 3.

As described above, in the friction drive device according to the present invention, the backup roller 2 can rotate and translate in the plane orthogonal to the slider 3, as shown in FIG. In addition, even when the parallelism between the friction surfaces 3a and 3b of the slider 3 is poor and the drive roller 1 is tilted as shown in FIG. 2B, the backup roller 2 rotates and moves in parallel. As a result, the outer peripheral surface of the backup roller 2 and the friction surfaces 3a and 3b of the slider 3 make uniform line contact. Therefore, as in the conventional case, the point of contact between the backup roller 2 and the slider 3 causes severe wear of only the point-contacted area, and the displacement of the slider 3 becomes unstable. It is possible to prevent the linear displacement amount of 3 from becoming non-proportional.

In order to ensure that the outer peripheral surface of the backup roller 2 is in linear contact with the friction surface 3 b of the slider 3, the elastic force of the leaf spring 7 of the elastic parallel displacement mechanism 6 is changed by the weight of the backup roller 2. The spring 7 may be adjusted to have a strength such that it can be easily bent, or even if the rotating shaft 10 is elastically biased by a torsion spring or the like in the direction in which the backup roller 2 is pressed by the slider 3. good.

[0018]

According to the friction drive device of the present invention, even if the parallelism between the friction surfaces of the slider is poor or the drive roller is tilted, the outer peripheral surfaces of the drive roller and the backup roller and the friction surface of the slider. It is possible to make parallel with and to make uniform line contact. Therefore, it is possible to prevent partial wear of the slider and the like to prolong the life of the slider, and to displace the slider in a stable manner, thereby improving the accuracy of the displacement amount of the slider.

[Brief description of drawings]

1A and 1B are a partially cutaway front view and a partially broken side view, respectively, of a friction drive device according to an embodiment of the present invention.

2A and 2B are side views for explaining the operation of the same.

3A and 3B are a partially cutaway front view and a partially broken side view, respectively, of a conventional friction drive device.

4 (a) and (b) are partially cutaway side views showing the above problems.

[Explanation of symbols]

 1 Drive roller 2 Backup roller 3 Slider 5 Support shaft 6 Elastic parallel displacement mechanism 10 Rotating shaft

Claims (1)

[Scope of utility model registration request] 1. A friction drive device in which a slider is sandwiched between a drive roller and a backup roller which are arranged substantially parallel to each other, and the frictional motion between the drive roller and the slider converts the rotational motion of the drive roller into a linear motion of the slider. The backup roller is rotatably supported by rotatably supporting the base end of an elastic parallel displacement mechanism in which the tip end is elastically displaced in parallel in the lateral direction around a direction parallel to the slider movement direction. A friction drive device characterized in that a supporting portion for holding is provided at a tip portion of an elastic parallel displacement mechanism.