JPH0613135B2 - Grooved fluid bearing manufacturing equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a grooved fluid bearing for forming a groove of high precision on a surface of a metal material with a minute amount of plastic deformation.

2. Description of the Related Art In recent years, grooved fluid bearing manufacturing methods and apparatuses have, for example, the structure shown in FIG.

That is, the ball 3 that is in contact with the circumferential portion of the fixing pin 2 is fitted into the hole 5 formed in the circumferential direction near the tip of the tool shaft 1,
By crimping the outermost periphery of the hole 5 of the tool shaft 1, the ball 3
The groove 4 can be formed on the inner surface of the metal material 7 by fixing the above to form an integrated tool, and rotating and straightening the tool.

However, with such a structure, a gap 7 is formed in the joint surface between the ball 3b and the fixing pin 2 when the ball 3b is fixed by caulking. Or, when the groove depth dimension changes due to elastic deformation of the groove 5 machined in the metal material 4, or the diameter of the ball 3 decreases due to wear,
There is a problem that the dimensional accuracy of the groove 5 is reduced due to the dimensional accuracy of the tool and the material characteristics.

That is, since transfer processing is performed on the inner surface of the metal material 7 by rolling, the dimensional accuracy of the mating side is determined by the shape and dimensional accuracy of the tool to be transferred. For these reasons, it is difficult to maintain the tool precision such as the adhesion (gap) between the ball 3b and the fixing pin 2, the amount of elastic deformation of the metal material 7 and the wear of the ball surface.

In view of this, the present invention intends to provide a variable tool size structure so that the accuracy of the tool can be easily maintained and that the elastic deformation amount of the fluctuating material can be immediately dealt with.

Means for Solving the Problems In order to solve the above problems, the grooved fluid bearing manufacturing apparatus according to the present invention is fitted with a tool shaft having a hollow portion at its tip and a hollow portion, and From a cylindrical multi-stage movable pin with a multi-stage diameter, a ball that fits into a predetermined hole on the circumference near the tip of the tool shaft, and an elastic deformation ring that makes this ball and the multi-stage movable pin closely contact and fixes the ball. The groove is formed by transfer processing of the ball.

Operation The present invention has the above-described configuration, so that the ball can be inserted into the hole on the circumference near the tip of the tool shaft without applying an external force when assembling the tool, and the ball is always fixed on the contact surface of the multi-stage movable pin by the elastic deformation ring. The contact length of the balls is made stable by the contact pressure, and the forming accuracy of the groove on the inner surface of the metal material by the transfer process is also stable. On the other hand, the dimensions can be easily changed by sliding the multi-stage movable pin against variations in the groove dimensions caused by variations in the elastic deformation of the metal material.

As a result, there is no gap between the ball and the fixing pin as in the past, the elastic transfer of the metal material, the deterioration of the groove transfer accuracy due to the wear of the ball surface, etc. does not occur, and the groove transfer accuracy is improved and the size is very small. Control is possible, and productivity and cost can be improved.

Embodiment Hereinafter, a method and apparatus for manufacturing a grooved fluid bearing according to an embodiment of the present invention will be described with reference to the accompanying drawings. First
The drawing shows the arrangement of tools in the groove machining state of the method and apparatus for manufacturing a hydrodynamic bearing in the first embodiment of the present invention. In FIG. 1, 1 is a tool shaft, 2 is a multi-stage movable pin, 3 is a ball, 4 is a metal material, 5 is an elastically deformable ring, and the multi-stage capable pin 2 fitted with a tool shaft 1 by a screw is a multi-stage. The diameter of the contact surface with the ball 3 is variable by moving the movable pin back and forth in the axial direction by the action of the screw. Further, the ball 3 is fitted in the hole in the circumferential direction of the tool shaft 1, and the elastically deformable ring 5 attached to the outer periphery of the tool shaft 1 always maintains the multi-stage movable pin 2 even if the diameter of the multi-stage movable pin 2 changes. The outer peripheral surface of 2 is closely attached and fixed.

The operation of the method and apparatus for manufacturing the grooved fluid dynamic bearing configured as described above will be described below with reference to FIG.

FIG. 2 shows a tool arrangement after the dimension adjustment in the first embodiment, in which the multi-stage movable pin 2 of the multi-stage movable pin 2 is rotated by rotating the multi-stage movable pin 2 screwed onto the tool shaft 1. When the ball contact portion moves along the axial direction, the diameter of the ball contact portion of the multi-stage movable pin 2 changes, and the two balls 3a,
The relative length 6 of 3b expands and contracts. At this time, ball 3
The elastic deformation ring 5 attached to the tool shaft 1 causes the elastic deformation rings 5a and 3b to constantly press the ball contact portion of the multi-stage movable pin 2 to fix the balls 3a and 3b and maintain their dimensional accuracy. When the tool set in this way is inserted into the inner diameter of the metal material 4, the balls 3a and 3b are always pressed against the multi-stage movable pin 2 side by the reaction force of the transfer processing force. Relative length 6
The transfer process can be performed with high accuracy without any change.

As described above, according to the present embodiment, the pins for maintaining the relative length 6 of the balls 3a and 3b are integrally movable pins having different diameters, and the elastic deformation ring 5 is provided for holding the balls 3a and 3b. By providing it, it is possible to prevent a decrease in tool dimensional accuracy, elastic deformation of metal materials, deterioration of transfer accuracy due to wear of the ball surface, etc.
Productivity and cost can be improved.

EFFECTS OF THE INVENTION As described above, according to the present invention, a tool shaft having a hollow portion at its tip is fitted in the hollow portion, and a cylindrical multi-stage movable pin having a multi-step diameter from the fitting portion and the tool shaft tip vicinity. By providing a ball fitted in a predetermined hole on the circumference of the ball and an elastic deformation ring for closely adhering the ball and the multistage movable pin and fixing the ball, the accuracy of the tool dimension is reduced, the elastic deformation of the metal material, It is possible to prevent the transfer accuracy from deteriorating due to wear of the ball surface, etc., and it is possible to perform minute dimension control.

[Brief description of drawings]

FIG. 1 is a block diagram of a method and apparatus for manufacturing a grooved fluid bearing in a first embodiment of the present invention, FIG. 2 is a block diagram of FIG. 1 after dimension adjustment, and FIG. 3 is a conventional grooved fluid. It is a block diagram about the manufacturing method and apparatus of a bearing. 1 ... Tool axis, 2 ... Multi-stage movable pin, 3 ... Ball, 5
...... Elastic deformation ring, 6 ...... Groove.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hideaki Ohno 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP 58-202920 (JP, A) (JP, U)

Claims (1)

[Claims] 1. A groove for a grooved hydrodynamic bearing is formed so that it has an outer diameter that fits into a bearing hole of a workpiece, a hollow portion is provided at the tip, and a circumferential direction is provided at a predetermined location of the hollow portion. Fitted in the hollow part of the tool shaft and the tool shaft provided with a predetermined hole toward
A cylindrical multi-step movable pin having a multi-step diameter from the fitting part and a predetermined hole of the tool shaft are fitted, and in contact with the multi-step surface of the multi-step movable pin, the inner peripheral surface of the bearing hole of the workpiece. A groove with which a ball is formed by being pressed into contact with the ball and an elastically deformable ring that fixes the ball to the multi-step movable pin and fixes the ball, and the groove is formed by transfer processing of the ball Fluid bearing manufacturing equipment.