JP2008002631A - Ball retainer for linear motion guide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ball retainer reduced in rattling when fixed to a bearing while being enabled in molding by pressing work. <P>SOLUTION: On both side faces of the ball retainer 14, bent portions 14a are formed by bending a thin-plate stainless spring steel inward. At the longitudinal end of the ball retainer 14, a lock portion 14b is formed by inclining the thin-plate stainless spring steel. On the back face side of the ball retainer 14, a protruded portion 14c is formed by pressing work. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a ball cage for a linear motion guide device, and is particularly suitable for application to a simple ball holder that has been pressed.

  In the linear motion guide device, a long rail and a bearing are provided, and a rolling element rolling groove is formed in the rail and the bearing in parallel to the longitudinal direction of the rail, and the ball rolls in the rolling element rolling groove. It is configured to go forward. When the ball reaches one end of the bearing body, the ball is scooped up at the tip of the end cap, and is guided to a circulation hole formed in the bearing body through a return guide provided in the end cap. Then, when the ball passes through the circulation hole and exits to the other end of the bearing body, it passes through a return guide provided in the opposite end cap and returns to the rolling element rolling groove facing the rail and the bearing body. And the ball can make an infinite circulation.

Here, in a bearing other than the length set as a standard specification, a thin stainless steel spring is used as shown in FIG. 5 in order to prevent the hole from falling off the bearing when the bearing is removed from the rail. A simple ball holder 114 manufactured by pressing steel may be used (Patent Document 1).
In this ball cage 114, a bent portion 114a for pressing the ball against the bearing side and holding the ball in the rolling element rolling groove, and a thin plate for fitting the ball gap to the end gap and fixing the ball cage 114 The locking portion 114b is provided.
Japanese Unexamined Patent Publication No. Hei 8-284954

However, in the simple ball holder 114 manufactured by pressing, since the thin plate engaging portions 114b provided at both ends of the ball holder 114 are fitted into the gap on the end gap side and fixed, There was a problem that rattling occurred in the cage 114 and the balls spilled from the bearings.
SUMMARY OF THE INVENTION An object of the present invention is to provide a ball cage for a linear motion guide device that can reduce backlash when it is fixed to a bearing while allowing molding by press working.

  In order to solve the above-described problem, according to the ball cage of the linear motion guide device according to claim 1, in the ball cage of the linear motion guide device that holds the rolling element in the rolling element rolling groove in the bearing, A bent portion formed by bending a side end portion of the metal plate inward, a locking portion provided at the front and rear ends of the metal plate and fitted in a recess provided in an end cap of the bearing, and the metal plate And a projecting portion formed by press working on the back side.

  As described above, according to the present invention, the ball cage can be fixed by fitting the engaging portion into the gap on the end gap side while suppressing the back side of the metal plate with the bearing. For this reason, even when the ball cage is composed of a thin metal plate, it is possible to suppress the backlash of the ball cage and to form a protrusion by press working. Can be manufactured at low cost.

Hereinafter, a linear motion guide apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a schematic configuration of a linear guide apparatus according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a schematic configuration of the linear guide apparatus of FIG.
In FIG. 1, the linear motion guide device is provided with a long rail 11 and a bearing 12 having a U-shaped cross section. The bearing 12 can slide on the rail 11 so as to straddle the upper surface of the rail 11. It is fitted. Here, on both side surfaces of the rail 11 and the inner side surface of the bearing 12, rolling element rolling grooves 15 that are arranged to face each other are formed, and in the rolling element traveling passage constituted by these rolling element rolling grooves 15. A ball 16 that can run freely is arranged.

In the bearing 12, circulation holes arranged in parallel with the rolling element rolling grooves 15 are provided, and end caps 13 are provided on both end faces of the bearing 12. The end cap 13 is formed with a return guide that forms an infinite circulation path of the ball 16 by communicating the rolling element travel passage formed by the rolling element rolling groove 15 and the circulation hole.
A ball cage 14 is mounted in the bearing 12 so as to face the upper surface of the rail 11. Here, the ball cage 14 can be manufactured by pressing a thin stainless steel spring steel.

FIG. 3 is a plan view and a side view showing a schematic configuration of the ball cage according to the first embodiment of the present invention.
In FIG. 3, bent portions 14 a formed by bending a thin stainless steel spring steel inward are formed on both side surfaces of the ball cage 14, and thin stainless steel materials are formed at the front and rear ends of the ball cage 14. A locking portion 14b configured by inclining the spring steel is formed, and a projection 14c formed by pressing is formed on the back side of the ball cage 14. The protrusion 14c may have a clog shape as shown in FIG. 3, or a rectangular protrusion 14d as shown in FIG.

  Then, the ball holder 14 is mounted in the bearing 12 so as to face the upper surface of the rail 11, and the bent portion 14 a is brought into contact with the uppermost ball 16, so that the uppermost ball 16 is brought into contact with the bearing 12. The ball 16 can be held in the bearing 12 by pressing against the rolling element rolling groove 15 on the side. Further, when the ball cage 14 is fixed in the bearing 12, the locking portion 14 b can be fitted into the gap 13 a on the end gap 13 side while the protrusion 14 c is in contact with the inner upper surface of the bearing 12.

  Accordingly, the ball holder 14 can be fixed by fitting the engaging portion 14b into the gap 13a on the end gap 13 side while suppressing the back side of the ball holder 14 on the inner upper surface of the bearing 12. For this reason, even when the ball cage 14 is made of a thin stainless steel material, it is possible to suppress rattling of the ball cage 14 and to form the protrusions 14c by pressing. The ball cage 14 can be manufactured at low cost.

It is a perspective view showing a schematic structure of a linear motion guide device according to an embodiment of the present invention. It is sectional drawing which shows schematic structure of the linear motion guide apparatus of FIG. It is the top view and side view which show schematic structure of the ball holder which concerns on 1st Embodiment of this invention. It is the top view and side view which show schematic structure of the ball holder which concerns on 2nd Embodiment of this invention. It is the top view and side view which show schematic structure of the conventional ball holder.

Explanation of symbols

11 Rail 12 Bearing 13 End cap 13a Clearance 14 Ball cage 14a Bending part 14b Locking part 14c, 14d Protrusion part 15 Rolling element rolling groove 16 Ball

Claims (1)

In the ball cage of the linear motion guide device that holds the rolling element in the rolling element rolling groove in the bearing,
A bent portion formed by bending the side end of the metal plate inward;
A locking portion provided at the front and rear ends of the metal plate and fitted into a recess provided in an end cap of the bearing;
A ball cage for a linear motion guide device, comprising: a protrusion formed on the back side of the metal plate by pressing.

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