JP2666627B2 - Disc manufacturing method for disc friction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to selectively pressing and contacting disks to brake the rotation of one disk, or to transmit the rotation from one disk to the other disk. The present invention relates to a method for manufacturing a disk of a disk friction device applied to equipment used in a vacuum.

[0002]

2. Description of the Related Art For example, a conventional electromagnetic friction brake has the following structure. First, there are a brake side and a brake side, and a brake side disk and a brake side disk are mounted on these brake side and brake side, respectively.
The brake side disk is made of metal, and the brake side disk is made of an organic friction material. The brake-side disc is pressed against the brake-side disc to stop the brake-side rotation. Incidentally, a disc made of an organic friction material may be used as the braking side disc. By the way, the surface processing of the above-mentioned conventional metal disk is performed by processing means such as mechanical polishing, for example, and the surface is in an irregular state having no regularity by such normal processing means. The surface roughness of the conventional metal disk is Ra = 0.05 μm, and its maximum height Rmax
It is described that Ra is about 2 μm in the following document (1) for Ra, and Rmax is described in the following document (2). In addition, it is clear from the literature shown in (3) that research on brake materials for vacuum and space brakes is still ongoing. (1) Hawthone, HM: Wear Debris Induced Friction Anoma
lies of Organic BrakeMaterials in Vacuo, Wear Mate
r, Vol. 1 (1987), p. 381-p. 764. (2) Iwata, Machida, Toda: Braking materials for space actuators, Tribologist, Volume 34, No. 10 (1989), pp. 757-76.
Four. (3) Hawthone, HM: On the Role of Interfatial Debris
Morphology in a Confor-ming Contact Tribosystem, 8
th Int. Conf.on Wear of Materials, ASME (1991), P.
277-P.288.

[0003]

However, according to the above-mentioned prior art, there are the following problems. That is, when the electromagnetic friction brake is used in a vacuum, the frictional force suddenly drops at a certain distance, and the desired braking function cannot be exhibited. is there. This will be described with reference to FIG. FIG.
Is the slip distance on the horizontal axis and the friction coefficient on the vertical axis.
It is a figure showing the relation between both. Also, the braking side disk used in the experiment was made of metal (mild steel) and its surface roughness was
The maximum height (Rmax) is 1 μm, and the disc to be braked is made of an organic friction material. A diagram a in the figure is data in the atmosphere, and a diagram b is data in a vacuum. As is clear from FIG. 4, in a vacuum,
It can be seen that when the slip distance exceeds a certain value, the friction coefficient sharply decreases. As a similar phenomenon, an example in which a stainless steel having a surface roughness (Ra) of 0.05 μm is used as the braking-side disk in the above-mentioned document (1) is described. There was a problem in applying it to equipment used for SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing a disk for a disk friction device which solves the above-mentioned problems (problems) of the conventional one.

[0004]

According to the present invention, a disc made of an organic friction material and a disc made of a metal are selectively pressed and pressed.
A metal disk in a disk friction device used in a vacuum that exerts a braking function or a rotation transmitting function by being brought into contact with the disk is processed by a processing means using thermal spraying such as laser spraying or plasma spraying. A disk having a partial projection on the surface of the disk and processed so that (surface roughness or representative height of a metal disk) / (surface roughness of an organic disk)> 1 The present invention relates to a method for manufacturing a disk of a friction device.

In this case, instead of thermal spraying, the surface processing of the metal disk is performed by applying a dent such as shot peening, shot blasting, or the like, or by using a mold, or by plating, etching, or pattern etching. Or other special processing means such as sintering, casting, die casting, hot isostatic pressing (HIP), or cold isostatic pressing (CIP).

[0006]

According to the method of manufacturing a disk of the present invention, the surface of a metal disk is processed by a special processing means such as thermal spraying, and the surface of the disk is formed as a surface having partial projections.
Since the processing is performed so that (surface roughness or representative height of metal disk) / (surface roughness of organic material disk)> 1, a reduction in frictional force in a vacuum is prevented.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. This embodiment shows a configuration example in which a disk manufactured by the manufacturing method of the present invention is applied to an electromagnetic friction brake. In FIG. 1, reference numeral 1 denotes a rotating shaft 1 on the braked side.
A disk 3 to be braked is spline-fitted to the rotating shaft 1 via a hub 2. The brake-side disk 3 is made of an organic friction material (for example, a polyimide resin material, a phenol resin material, or the like). Also, the left and right sides in the figure are the braking surfaces 5, 5 '. On the other hand, a pair of braking-side disks 7 and 9 are arranged as the braking side. The braking side disks 7, 9 are
Are arranged so as to sandwich the. The braking side disk 7,
Among them, the braking side disk 9 is fixed to the substrate 13 by a screw member 11 such as an adjusting bolt. On the other hand, the braking-side disk 7 is installed so as to be movable in the left-right direction by sliding on a collar 7a in the figure, and is urged in the direction of the braking-side disk 3 by a coil spring 15. When the electromagnetic coil 17 is energized, it moves to the left in the figure against the spring force of the coil spring 15.

When the electromagnetic coil 17 is in a non-energized state, the pair of brake-side disks 7 and 9 press and contact the brake-receiving surfaces 5 and 5 'of the brake-side disk 3.
A desired braking function is exhibited, and the rotation of the rotating shaft 1 is regulated. On the other hand, when the electromagnetic coil 17 is in the energized state, the braking side disk 7 is separated from the braked surface 5 of the disk 3 to be braked, so that the braking function is stopped, and the rotating shaft 1 is stopped. Rotation is allowed.

Incidentally, the braking side disks 7, 9 are made of metal (for example, mild steel, austenitic stainless steel, aluminum alloy, titanium, various surface-treated steels, etc.), and the surface thereof is shown, for example, in FIG. It is manufactured by the following eleven special processing methods so as to have a configuration. In FIG. 2, Rmax (Ra) indicates the surface roughness of the disk substrate, and Rd indicates the representative height of the projections provided by the above various special processing methods. (1) Processing by means of thermal spraying First, the disk surface is processed by processing means using thermal spraying such as laser spraying or plasma spraying. For example, as shown in FIG. partial projections 20a ₁ on the surface of the disk, 20a _2, and the surface having a ..., (surface roughness or representative height of the metallic disk) / (surface roughness of the organic material-made disc)> 1 and so as To produce a disk. In addition, the machining mode that satisfies the above condition, FIG. 2 (B), the protrusion 20b ₁ the shape of the portion projection as shown in _{(C), 20b 2,;} 20c 1,
Various embodiments are conceivable by transforming them into 20c ₂ ,. In addition, there are the following ten methods as special processing means for forming a partial projection on the surface of the metal disk and satisfying the above conditional expression. (2) Indentation of shot peening, shot blasting, etc. (3) Indentation using mold (4) Plating (5) Etching (6) Pattern etching (7) Sintering (8) Casting (9) Die Cast (10) Hot isostatic pressing (HIP) (11) Cold isostatic pressing (CIP)

The relationship between the ratio of the surface roughness of a metal disk to the surface roughness of a disk made of an organic friction material and the frictional force will be described with reference to FIG. In FIG. 3, the horizontal axis represents (surface roughness of a metal disk) / (the surface roughness of an organic friction material disk), and the vertical axis represents a slip distance (L _0.2) until the dynamic friction coefficient decreases to _0.2. ) Is a diagram showing the change. In this case, the disc made of an organic friction material of the same material as the disc 3 to be braked is rubbed against the unidirectionally polished metal disc of the same material as the discs 7 and 9. It was done. In the case of a metal disk having a special partial projection according to the present invention, the horizontal axis in FIG. 3 is (surface roughness or representative height of the metal disk).
// (surface roughness of organic material disc). In this case, as is clear from FIG. 3, when the surface roughness of the metal disk is smaller than the surface roughness of the disk made of an organic friction material, the dynamic friction coefficient is about 0.5 km at most.
It drops to 0.2. Also, at that time, the friction surface after the test is darkened. On the other hand, when the surface roughness ratio R _S is 1 or more, a slip distance of 3 km or more is shown, and some of them show a slip distance of 10 km or more. That is, by setting the surface roughness ratio R _S to 1 or more, it is possible to prevent a decrease in frictional force. In this case, the organic friction material adheres to the surface of the metal disk in a mottled manner, and its color is close to the color of the chip of the organic friction material, which is completely different from the former. there were. As described above, in the electromagnetic friction brake using the disk manufactured by the working method of the present embodiment, it is possible to prevent a decrease in frictional force in a vacuum and exhibit a stable braking function for a long time. This is because the surface roughness or the representative height of the metal braking side disks 7, 9 is configured to be larger than the surface roughness of the organic material braking side disk.

The present invention is not limited to the above embodiments. For example, in each of the above-described embodiments, the friction type electromagnetic brake device has been described as an example, but the same effect can be obtained by applying to a friction type electromagnetic clutch device.

[0012]

As described above, according to the disk manufacturing method of the disk friction device according to the present invention, the surface roughness or the representative height of the metal disk can be reduced by the special processing means such as thermal spraying. Since it is processed so as to be larger than the surface roughness of the disc made, it has the following excellent effects. In the processing method of the present invention is to impart conventional ordinary metal processing methods partial projections 20a of the representative height Rd shown in unrealizable 2 in _1, 20a ₂ ... a metal disk surface An electromagnetic friction brake using a disk processed so that the surface roughness or the representative height of a metal disk is larger than the surface roughness of an organic material disk is to prevent a reduction in frictional force in a vacuum. Can be. Therefore, since the electromagnetic friction brake using the disk manufactured by the manufacturing method of the present invention can maintain a stable function for a long time in a vacuum, it can be used for vacuum or space equipment such as a space station. It is suitable as a disc friction device applied to applications such as a brake for holding and stopping a joint of a manipulator in the above, and the utility of the present invention is great.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing a configuration of an electromagnetic brake device to which an embodiment of the present invention is applied.

FIG. 2 is a sectional view of a main part showing a surface processing state of a metal disk processed by a special processing means such as thermal spraying according to the present invention, wherein (A) to (C) are processing forms (embodiments) of the present invention, respectively. 3) shows an example.

FIG. 3 is a diagram showing the operation of one embodiment of the present invention, showing the relationship between the surface roughness ratio R _S and the frictional force, and the surface roughness ratio R _S and the slip distance until the dynamic friction coefficient decreases to 0.2. Shows the relationship.

FIG. 4 is a diagram used for explaining a conventional example, and is a diagram showing a comparison between a slip distance and a friction coefficient in the air and in a vacuum.

[Explanation of symbols]

 3: Disc to be braked 7: Disc to be braked 9: Disc to be braked

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-62-88830 (JP, A) JP-A-64-79432 (JP, A) JP-A-5-42635 (JP, A) 177230 (JP, U) JP-A 3-19129 (JP, U) JP-A 63-126632 (JP, U) JP-A 53-35351 (JP, U) JP-B 38-8224 (JP, B1)

Claims (11)

(57) [Claims] 1. A disk friction device used in a vacuum which exerts a braking function or a rotation transmitting function by selectively pressing and contacting a disk made of an organic friction material and a metal disk. Insert the disk
The surface of the disk is provided with partial protrusions by a processing means using thermal spraying such as thermal spraying or plasma spraying, and (surface roughness or representative height of metal disk) / (surface of organic material disk) (Roughness)> 1. A method of manufacturing a disk for a disk friction device, wherein the disk is manufactured by processing. 2. A method of manufacturing a disk for a disk friction device according to claim 1, wherein the surface processing of said metal disk is performed by a processing means such as shot peening, shot blasting or the like instead of thermal spraying. . 3. A method for manufacturing a disk for a disk friction device according to claim 1, wherein the surface processing of said metal disk is performed by a pressing means using a mold instead of thermal spraying. 4. The method of manufacturing a disk for a disk friction device according to claim 1, wherein the surface processing of said metal disk is performed by plating instead of thermal spraying. 5. The disk manufacturing method for a disk friction device according to claim 1, wherein the surface processing of said metal disk is performed by processing means called etching instead of thermal spraying. 6. A method of manufacturing a disk for a disk friction device according to claim 1, wherein the surface processing of said metal disk is performed by processing means called pattern etching instead of thermal spraying. 7. The disk manufacturing method for a disk friction device according to claim 1, wherein the surface processing of said metal disk is performed by processing means called sintering instead of thermal spraying. 8. The method of manufacturing a disk for a disk friction device according to claim 1, wherein the surface processing of said metal disk is performed by processing means called casting instead of thermal spraying. 9. The method of manufacturing a disk for a disk friction device according to claim 1, wherein the surface processing of the metal disk is performed by die casting instead of thermal spraying. 10. The disk manufacturing method for a disk friction device according to claim 1, wherein the surface processing of the metal disk is performed by hot isostatic pressing (HIP) instead of thermal spraying. 11. The method of manufacturing a disk for a disk friction device according to claim 1, wherein the surface processing of the metal disk is performed by cold isostatic pressing (CIP) instead of thermal spraying.