JPH0558946U - Ball bearing for linear motion with built-in ball screw - Google Patents

Abstract

(57) [Summary] [Purpose] Gives sufficient rigidity to the bearing body of the linear motion ball bearing and integrates it with the ball screw. [Structure] The bearing body 10 has ball rolling surfaces 11 and 11 'and ball return holes 12 provided on both end surfaces facing outward. Grooves 13, 13 'provided at the end of the ball return hole 12
The J-shaped pipes 30 and 30 'facing each other are incorporated in the. The end cap 40 is a pipe 30,3
0'is fixed, and the seal 50 is fixed to the outside thereof. The raceways 70, 70 ′ are provided outside the bearing body 10, and the ball transfer surface 1 provided on the bearing body 10
It has ball rolling surfaces 71, 71 'having a shape complementary to 1, 11'. The bearing body 10 further has an internal thread 14 extending through its length. A male screw shaft 80 is screwed onto the female screw 14.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a linear motion ball bearing used for guiding a linear motion part such as a table or a positioning table of a machine tool.

[0002]

[Prior art and its problems]

 Conventionally, this type of ball bearing is almost always shaped like a U-shaped bearing body with an open bottom that straddles the way, and a ball bearing installed on the inward side of the bearing body. The ball is sandwiched between the rolling surface and the rolling surface of the ball provided on both sides of the raceway facing outward. Therefore, when a load is applied, both of the U-shaped skirt portions tend to be bent outward, and there is a drawback that the rigidity as a bearing cannot be sufficiently obtained.

Further, a table or the like incorporating this type of bearing is usually moved linearly by a ball screw mechanism, but this type of conventional bearing cannot be integrated with the ball screw, and the ball cannot be integrated in another place. It was necessary to provide a screw mechanism. When the ball screw mechanism and the linear motion bearing mechanism are separate bodies, if the mounting parallelism between them is poor, an unbalanced load will act on the ball screw, causing heat generation of the ball screw and deterioration of accuracy. become.

[0004]

[Means and Actions for Solving Problems]

 In this invention, a bearing main body formed with a female screw to be screwed with a male screw shaft through a ball of a ball screw has ball rolling surfaces on both outward facing surfaces, and is provided on a raceway arranged outside thereof. The above-mentioned problem is solved by the structure in which the ball is sandwiched between the ball rolling surface.

The basic function of the linear motion ball bearing of the present invention is the same as that of the conventional one, but the bearing body has ball transfer surfaces on both end faces facing outward and is provided on a raceway arranged outside thereof. Since the ball is sandwiched between it and the ball transfer surface, there is no decrease in rigidity due to the outward bending of the skirt as in the conventional case, the rigidity of the bearing can be increased, and it is also integrated with the ball screw mechanism. be able to.

[0006]

【Example】

 In FIG. 1, reference numeral 10 is a bearing main body, and ball rolling surfaces 11, 11 'are provided in double rows on both outer end surfaces thereof. This ball rolling surface may be a single row.

By adopting a circular arc groove type in the case of a double row and a gothic arc groove type in the case of a single row, it is possible to receive a load with vertical and horizontal directions and a moment. This kind of bearing is similar.

In order to allow the balls 20 to have an endless circulation motion, the bearing body 10 is provided with ball return holes 12 (only one of the four is shown).

Then, in order to change the direction of the ball 20 and prevent the ball from falling off, the J-shaped pipes 30 and 30 ′ facing each other are provided in the grooves 13 and 13 ′ provided at the ends of the ball return holes. Built in. This pipe is shown only in the front end face of the bearing body 10 in FIG.

At the end of the bearing body 10 in the longitudinal direction, an end cap 40 having grooves 41 and 41 ′ for fixing the ends of the pipes 30 and 30 ′ is attached from both directions, and a seal 50 is put from the outside of the end cap 40. Bolt 60 to fix. Spacers may be inserted between the upper and lower pipes.

The raceways 70, 70 ′ are provided so as to press the bearing body 10 from both outer sides, and the ball rolling surface 71 having a shape complementary to the ball transfer surfaces 11, 11 ′ provided on the bearing body 10. , 71 '.

As shown in FIG. 2, the J-shaped pipes 30 and 30 ′ facing each other have a window-like portion 31 through which the ball 20 is exposed, and the ball in this portion has a window-shaped portion 31. It is sandwiched between the ball rolling surfaces 11 and 11 'of and the ball rolling surfaces 71 and 71' of the raceways 70 and 70 'to share the load. In this portion, the ball is exposed only at a portion corresponding to about one-fourth of the circumference, so that the ball 20 does not drop even if the bearing body 10 and the raceways 70, 70 'are separated.

It should be noted that the pipes 30 and 30 ′ can also be used by combining two pipes having a split shape.

Next, the ball screw mechanism will be described. A female screw 14 for use as a ball nut of the ball screw is provided to penetrate the bearing body 10 in the longitudinal direction. 15 and 15 'are tubes for circulating balls (not shown) of a ball screw.

The male screw shaft is shown by reference numeral 80, and a seal (wiper) 90 for preventing leakage of lubricant and dust prevention, a through hole 51 of the seal 50, a through hole 51 of the end cap 40, and an end cap. The balls are threaded through the through holes 42 of 40, and are screwed into the female screw 14 with balls interposed.

Since the ball screw mechanism is well known, detailed description will be omitted.

Next, FIGS. 4 to 6 show specific examples of use of the linear motion ball bearing of the present invention.

In the case of FIG. 4, two bearing bodies 10A and 10B are bolted to the table T and sandwiched between three bearing stands 70A, 70B and 70C. One of them 10B has a built-in ball screw mechanism.

In FIG. 5, one bearing body 10C is sandwiched between two rails 70D and 70E, and the bearing body also has a built-in ball screw in this case.

Finally, in FIG. 6, the bearing main body 10 is provided with a flange portion, and the raceways 70F and 70G are not fitted in the grooves, unlike those in FIGS. 4 and 5. It is different, but the other points are the same.

[0021]

[Effect of the device]

 1 Since the ball rolling surfaces are formed on both outer end surfaces of the bearing body, the rigidity of the bare ring is increased. The processing of the two-ball transfer surface becomes easy. 3 With a built-in ball screw, it is possible to realize a compact one that does not take up much space. 4 It becomes easy to move and stop the bearing. 5 Since the internal thread of the ball screw can be machined with the ball rolling surface provided on the end surface of the bearing body as a reference, it is not necessary to consider the mounting parallelism of the linear motion bearing and the ball screw.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention.

FIG. 2 is a top view of a pipe.

FIG. 3 is a front view of a pipe.

FIG. 4 is a front view showing an example of use of the present invention.

FIG. 5 is a front view showing another example of use of the present invention.

FIG. 6 is a front view showing another example of use of the present invention.

[Explanation of symbols]

 10 Bearing body 11,11 'Rolling surface 14 Female screw 70,70' Track rail 71,71 'Ball transfer surface 80 Female screw shaft

Claims (1)

[Scope of utility model registration request] 1. A bearing main body formed with a female screw that is screwed with a male screw shaft through a ball of a ball screw has ball rolling surfaces on both outer end surfaces thereof, and balls provided on a raceway arranged outside thereof. A ball bearing for linear motion, characterized by sandwiching the ball with the rolling surface.