JPS648204B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a method for manufacturing a ball-equipped holder that faces and cooperates with a concave bearing surface of a mating member in a hydrodynamic spherical fluid (gas, oil, grease, etc.) bearing. It is related to.

Most of the conventionally known holding bodies with balls in this type of hydrodynamic bearing have a cylindrical material 1a, which serves as one of the holding bodies for the balls, as shown in FIG. The shaft body 2a having the shape shown is machined by turning, and then, as shown in FIG. 3, a ball 22a is attached to the tip of the small diameter shaft portion 21a of the shaft body 2a by electron beam welding, laser beam welding, spot welding, etc. Thus, the ball-equipped shaft body 3a is formed by welding and fixing, and then, in order to more completely align the center of the ball 22a of the ball-equipped shaft body 3a with the axis of the shaft body 2a, as shown in FIG. The shaft with the ball is rotated by the support means such as
The outer circumferential surface of a is finished by grinding, and then a groove for generating dynamic pressure, for example a spiral groove 23a, is formed on the top side of the ball 22a of the ball-equipped shaft.

However, with the above manufacturing method, there are drawbacks such as wear and scratches on the balls because the balls slide into contact with the support, especially during the grinding process shown in Figure 4. If the performance is adversely affected and the processability as a whole is poor, and furthermore, if the groove machining fails in the final process, it is not enough to just replace the ball, but the shaft body 3a with the ball is defective. Because they are processed as non-defective products, yields are poor and costs increase.
There were many problems in terms of productivity, resource conservation, etc.

The present invention eliminates the above-mentioned conventional drawbacks and problems and provides a method for manufacturing a ball-equipped holder that is superior not only in performance during use but also in terms of workability, productivity, cost, etc. .

Next, the manufacturing method of this invention is illustrated in FIGS. 6 to 11.
The embodiment shown in the figure will be described. Introduction No. 6
In the embodiment shown in FIGS. 6 to 9, a recess 12 in a small diameter portion 11 (a small diameter portion is not necessarily required) of a standard shaft body 1, which is one of the members for holding a ball 13, as shown in FIG. 6, for example. The ball 13 is temporarily fixed with adhesive to form the shaft body 2 with the ball, and then a groove for generating dynamic pressure, for example, is formed on the top side of the ball 13 by any conventional processing means. After forming the spiral groove 14, the ball 13 is removed from the shaft body 1 to complete the grooved ball 13 as shown in FIG. (However, in this case, if the grooved ball does not meet the specifications, it will be discarded as a defective product.) Next, for example, one of the ball holders shown in FIG. The shaft body 3 and the grooved ball are fixed to the tip of the small diameter portion 31 of the shaft body 3, with the apex P of the grooved ball 13 on the side opposite to the groove aligned with the axis of the shaft body 3, and closely fixed to each other. 13 to complete the ball-equipped shaft body 4, which is one of the ball-equipped holders.

In particular, as a means for fixing the shaft body 3 and the grooved ball 13, for example, Aron Alpha (trade name)
They are fixed by bonding with an instant adhesive such as, etc., or by welding means such as electron beam welding, laser beam welding, spot welding, etc.

FIG. 10 and FIG. 11 each show an embodiment of a ball holder having another shape instead of the shaft with a ball, which is one of the ball holders described above.
FIG. 10 shows a ball-equipped circular block holder 5 in which a ball 13 is held in a circular block having a flange portion 51 and a trapezoidal portion 52.
FIG. 11 shows a ball-equipped disk holder 6 that holds a ball 13 on one surface (one end surface) of a disk 61. As shown in FIG.

As described above, the ball-equipped holder (ball-equipped bearing body) used in the hydrodynamic spherical fluid bearing of the present invention is manufactured as described above.
There is no need for grinding for alignment after the ball holder and the ball are integrally connected, and therefore, wear and scratches on the ball can be reliably prevented as in the prior art.

In addition, there is no groove processing on the ball after the ball holder and the ball are integrally connected, and the ball is simply machined in advance to the specified dimensions and then fixed to the separately completed ball holder as specified. There is no occurrence of defective products after the balls are fixed, as in the conventional method, the overall yield is significantly improved, and a holder with balls that is suitable for mass production at low cost and of good quality can be obtained.

[Brief explanation of drawings]

1 to 5 are explanatory diagrams for explaining a conventional method for manufacturing a shaft with balls, and FIGS. 6 to 9 are explanatory diagrams for explaining a method for manufacturing a holding body with balls according to the present invention. Figures 10 and 11 are
Each of the figures shows another example of a ball-equipped holder manufactured by the method of the present invention. In the symbols of the embodiment, 1 is a standard shaft, 11 is a small diameter portion, 13 is a ball, 14 is a dynamic pressure generating groove, 3 is a shaft, P is the top of the ball, 4 is a shaft with a ball, 5
6 is a circular block holder with balls, and 6 is a disc holder with balls.

Claims (1)

[Scope of Claims] 1. After temporarily fixing a ball to one end of a member substantially concentrically with the member, a groove for generating dynamic pressure is formed on the top side of the ball on the opposite side to the fixation side, Thereafter, the ball is removed, and the removed ball is placed on one end side of a ball holder that has been prepared in a desired size and shape in advance, so that the apex of the ball on the side opposite to the groove and the axis of the ball holder are aligned. 1. A method for manufacturing a ball-equipped holder for a dynamic pressure type spherical fluid bearing, characterized in that the holder is fixed and formed so as to coincide with each other. 2. The method of manufacturing a ball-equipped holder for a hydrodynamic spherical fluid bearing according to claim 1, wherein the balls are fixed to the ball holder using an adhesive. 3. The method of manufacturing a ball-equipped holder for a hydrodynamic spherical fluid bearing according to claim 1, wherein the balls are fixed to the ball holder by welding. 4. A method of manufacturing a ball holder according to claims 1, 2, and 3, wherein the ball holder is a shaft. 5. A method of manufacturing a hydrodynamic spherical fluid bearing according to claims 1, 2, and 3, in which the ball holder is in the shape of a circular block or disk. 6. A method for manufacturing a ball-equipped holder for a hydrodynamic spherical fluid bearing, in which a ball is fixed in a center hole used for forming a shaft body, as set forth in claim 4.