JP2587876Y2 - Friction drive - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction drive.
More specifically, the present invention relates to a friction drive device that converts a rotational motion of a drive roller into a linear motion of a slider by a frictional force.

[0002]

2. Description of the Related Art FIGS. 3A and 3B show a conventional friction drive device C.
It is the front view and side view which fractured partially. In this friction drive device C, a backup roller 32 is rotatably mounted on a support shaft 35 via a bearing 34, and a slider 33 has a right angle between the drive roller 31 and the backup roller 32 arranged in parallel. The outer peripheral surface of the drive roller 31 and the friction surface 33a of the slider 33 are in linear contact, and the outer peripheral surface of the backup roller 32 and the friction surface 33b of the slider 33 are also in linear contact.

When the drive roller 31 is driven to rotate, 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 length direction.

[0004]

However, in the conventional friction drive device C, the friction surface 3 of the slider 33 is not provided.
When the parallelism between the backup rollers 3a and 33b is poor [FIG. 4 (a)] or when the drive roller 31 is inclined [FIG. 4 (b)], the outer peripheral surface of the backup roller 32 and the slider 33
There is a problem that the frictional surface 33b makes point contact, and the contacting portion becomes intensely worn, so that the backup roller 32 and the slider 33 are partially reduced.

When the backup roller 32 and the slider 33 come into point contact with each other, the drive roller 31
The frictional force between the slider 33 and the slider 33 becomes non-uniform, and the slider 33 cannot be displaced stably.

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

[0007]

The friction drive device of the present invention sandwiches a slider between a drive roller and a backup roller which are arranged substantially in parallel, and controls the rotational movement of the drive roller by friction between the drive roller and the slider. In a friction drive device that converts the movement into linear motion of the slider, the base end of an elastic parallel displacement mechanism that allows the distal end to be elastically displaced in the horizontal direction is rotated around a direction parallel to the direction of movement of the slider A support portion that is freely supported and rotatably holds the backup roller is provided at a distal end portion of the elastic parallel displacement mechanism.

[0008]

In the friction drive device according to the present invention, the base end of the elastic parallel displacement mechanism holding the backup roller is rotatable about a direction substantially parallel to the moving direction of the slider. Even if the friction surface of the slider is tilted, the backup roller rotates by rotating the base end of the elastic parallel displacement mechanism so that the outer peripheral surface is parallel to the friction surface of the slider. Furthermore, 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, and makes linear contact with the friction surface of the slider and makes uniform contact.

Therefore, even if the degree of parallelism between the opposed friction surfaces of the slider is poor, or if the drive roller is inclined, the backup roller rotates and translates, so that the backup roller is moved to the slider. Uniform line contact. Therefore, even in such a case, it is possible to prevent the slider or the like from being worn out or worn off due to the uneven contact, or the slider from becoming unstable.

Further, the backup roller rotates and translates only in a plane perpendicular to the slider, and does not become inclined with respect to the moving direction of the slider, so that the slider can always be displaced stably. Can be.

[0011]

1 (a) and 1 (b) are a partially cutaway 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 right angles between a drive roller 1 and a backup roller 2 which are arranged substantially in parallel.

The cylindrical backup roller 2 is rotatably attached to the distal end of a support shaft 5 via a bearing 4, and the base end of the support shaft 5 is connected to an elastic parallel displacement mechanism 6.
Is held at the tip. Also, the elastic parallel displacement mechanism 6
Is a rotating shaft 1 disposed in parallel with the slider 3.
The base of the rotating shaft 10 is rotatably held by a bearing 12 via a bearing 11. As a result, the support shaft 5 of the backup roller 2
Are arranged at right angles to the rotating shaft 10. In the illustrated example, the elastic parallel displacement mechanism is parallel to the rotation shaft 10 and orthogonal to the support shaft 5, but may be arranged perpendicular to the rotation shaft 10 and parallel to the support shaft 5.

Therefore, the backup roller 2 rotates around the rotation shaft 10 by rotating the rotation shaft 10, and can rotate in a plane perpendicular to the slider 3.

The elastic parallel displacement mechanism 6 has, for example, two leaf springs 7, 7 of the same length arranged in parallel with the leaf spring surfaces facing each other, and two ends of the leaf springs 7, 7 are supported by two support blocks 8. , 9, and the support block 8 on the distal end side is displaced so as to translate in the horizontal direction due to the elastic bending of the leaf springs 7, 7. A base end of the backup roller 2 is fixed to a support block 8 on the front end side, and a base end side support block 9 is fixed to a front end of the rotating shaft 10.

The rotation of the rotating shaft 10 causes the angle of the backup roller 2 to be inclined in parallel with 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. And the backup roller 2 moves to the slider 3
Is in line contact with the friction surface 3b. In addition, since the position of the backup roller 2 is controlled in parallel with the friction surface 3b of the slider 3 by the elastic parallel displacement mechanism 6, the outer peripheral surface of the backup roller 2 uniformly presses the friction surface 3b of the slider 3.

As described above, in the friction drive device of the present invention, since the backup roller 2 can rotate and translate in a plane perpendicular to the slider 3, as shown in FIG. Even when the degree of parallelism between the friction surfaces 3a and 3b of the slider 3 is poor, FIG.
As shown in FIG. 7, even when the drive roller 1 is inclined, the outer peripheral surface of the backup roller 2 and the slider 3 are rotated by the backup roller 2 rotating and moving in parallel.
Frictional surfaces 3a and 3b are in uniform line contact. Therefore, the point of contact between the backup roller 2 and the slider 3 as in the prior art causes severe wear of only the point contacted portion, or the displacement of the slider 3 becomes unstable, and the rotation amount of the drive roller 1 and the amount of rotation of the slider 3 become unstable. It is possible to prevent the linear displacement amount from becoming out of proportion.

In order to ensure that the outer peripheral surface of the backup roller 2 is in linear contact with the friction surface 3b of the slider 3, the elastic force of the leaf spring 7 of the elastic parallel displacement mechanism 6 is determined by the weight of the backup roller 2 by the weight of the backup roller 2. May be adjusted so as to easily bend, or the rotating shaft 10 may be moved in the direction in which the backup roller 2 is pressed by the slider 3.
May be elastically biased by a torsion spring or the like.

[0018]

According to the friction drive device of the present invention, even when the degree of parallelism between the friction surfaces of the sliders is poor or when the drive roller is inclined, the outer peripheral surfaces of the drive roller and the backup roller and the friction surface of the slider are maintained. Can be made parallel to make uniform line contact. Therefore, the wear can be extended by preventing partial wear of the slider and the like, and the slider can be displaced stably,
The accuracy of the displacement of the slider is also improved.

[Brief description of the drawings]

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

FIGS. 2 (a) and 2 (b) are side views for explaining the operation of the above.

FIGS. 3A and 3B are a partially broken front view and a partially broken side view of a friction drive device according to a conventional example.

FIGS. 4 (a) and 4 (b) are partially cutaway side views showing the same problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drive roller 2 Backup roller 3 Slider 5 Support shaft 6 Elastic parallel displacement mechanism 10 Rotation shaft

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16H 19/02 B65G 13/02 F16H 13/02

Claims (1)

(57) [Scope of request for utility model registration] 1. A friction drive device comprising a slider interposed between a drive roller and a backup roller disposed substantially parallel to each other, and converting a rotational motion of the drive roller into a linear motion of the slider by friction between the drive roller and the slider. A base end of an elastic parallel displacement mechanism in which a distal end portion is elastically displaced in a horizontal direction is rotatably supported around a direction parallel to a moving direction of a slider, and the backup roller is rotatably supported. A friction drive device, wherein a holding portion for holding is provided at a tip portion of the elastic parallel displacement mechanism.