JPS62200016A - Rectilinear motion ball bearing with built-in ball screw - Google Patents

Abstract

PURPOSE:To aim at improvement in rigidity, by constituting a bearing body, having an internal thread to be screwed with an external thread shaft via a ball of a ball screw, so as to have ball rolling surfaces at both outward end faces and to hold the ball in between the ball rolling surface and another ball rolling surface of the raceway block set up at the outside. CONSTITUTION:An internal thread 14 to be used for a ball nut of a ball screw is pierced through a bearing body 10 in the longitudinal direction. An external thread shaft 80 is screwed with the internal thread 14 through a wiper 90 for aim at leak prevention of a lubricant and dust proofing, a through hole 51 of a seal 50 and a through hole 42 of an end cap 40. On the other hand, the bearing body 10 and raceway blocks 70 and 70' are designed so as to hold the ball in between with ball rolling surfaces 11, 11' and 71, 71'. In consequence, rigidity in a bearing is improved as well as compactification in a device is well promoted.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a linear motion ball bearing used for guiding linear motion parts such as tables and positioning tables of machine tools.

Prior Art and its Problems Conventional ball bearings of this kind almost always have a shape in which the mouth-shaped bearing body straddles the gL track, and the ball bearings provided on the inward side of the bearing body are The ball is sandwiched between the raceway surface and the ball raceway surface provided on both outward facing sides of the track. Therefore, when a load is applied, both of the mouth-shaped skirt lips tend to bend outward, resulting in a drawback that sufficient rigidity as a bearing cannot be obtained.

In addition, tables incorporating this type of bearing are usually moved in a straight line by a ball mechanism, but conventional bearings of this type cannot be integrated with the ball holder, and the ball is placed in a separate location. It was necessary to provide a screw mechanism.

Means and Effects for Solving the Problems This invention provides a bearing body having a female thread that is threadedly engaged with a male threaded shaft through the balls of a ball screw, and has a ball rolling surface on both outward end surfaces thereof, and a ball rolling surface on the outside thereof. The above problem was solved by a configuration in which the balls are sandwiched between the ball rolling surfaces provided on the arranged track base.

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 rolling surfaces on both outward facing end surfaces, and the ball rolling Since the ball is sandwiched between the bearing and the running surface, there is no decrease in rigidity caused by the skirt bending outward as in conventional bearings, increasing the rigidity of the bearing, and it can be integrated with the ball driving mechanism. I can do it.

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

By adopting the circular error arc groove type for double rows and the gothic arc groove type for single rows, it is possible to receive vertical, horizontal, and moment loads compared to conventional methods. Similar to seed bearings.

In order to cause the balls 20 to have infinite circulation motion, a ball return hole 12 (only one of the four is shown) is machined in the bearing body 10.

In order to change the direction of the ball 20 and prevent the ball from falling off, pipes 30 and 30 are formed in the shape of three characters facing each other.
' is installed in the groove 13.13' provided at the end of the ball return hole. This pipe is the bearing body 1 in Figure 1.
The state in which it is provided only on the front end surface of 0 is shown.

An end cap 40 with grooves 41 and 41' for fixing the ends of the pipes 30 and 30' from both directions is attached to the longitudinal end of the bearing body 10, and a seal 50 is placed over the end cap 40 from the outside to secure the end cap 40 and the bolt 60. Fix it with. Note that a spacer may be interposed between the upper and lower pipes.

The track 70.70' is provided in such a manner as to press the bearing body 10 from both outside directions, and has a ball raceway surface 71.71 having a shape complementary to the ball raceway surfaces 11, 11' provided on the bearing body 10. 'have.

As shown in FIG. 2, the three-shaped pipes 30 and 30' facing each other have a window-like part 31 through which the ball 20 is exposed, and in this part, the The balls that travel ΦY, tl' are sandwiched between the ball rolling surfaces 71, 71' of the rails 70, 70', and share the load.

Since only a portion of the ball corresponding to about one-fourth of the circumference is exposed in this portion, the ball 20 will not fall off even if the bearing body 10 and the track base 70, 70' are separated.

Note that the pipes 30 and 30' can also be split into two parts.

Next, the ball screw mechanism will be described. A female screw 14 for use as a ball nut of a ball screw passes through the bearing body 10 in the longitudinal direction. 15
．． 15' is a tube for circulating the balls (not shown) of the ball screw.

The male threaded shaft is indicated by the reference numeral 80, and includes a seal (wiper) 90 for preventing lubricant leakage and dustproofing, a through hole 51 of the seal 50, and a through hole 42 of the end camp 40.
, and is screwed together with the female thread 14 with the ball interposed.

It should be noted that since the ball screw mechanism is well known, detailed explanation will be omitted.

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

In the case of Figure 4, there are three tracks? OA, 70B, 70C
Two bearing bodies 10A and IOB are bolted to the table T and sandwiched therebetween. one of them 1
0B has a built-in ball screw mechanism.

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

Finally, the bearing body 10D in Figure 6 is different from the bearing body 10D in that it has a flange portion, and the tracks 70F and 70G are not press-fitted into the grooves, unlike those in Figures 4 and 5. However, other aspects are the same.

Effect 1 of the invention: Since ball rolling surfaces are formed on both outward end surfaces of the bearing body, the rigidity of the bearing is increased.

2. Machining of the ball rolling surface becomes easier.

3. Since it has a built-in ball screw, it can be made compact and does not take up much space.

4. Easier to move the bearing and align the stop position.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view showing the first embodiment of the present invention;
The figure is a top view of the pipe, FIG. 3 is a front view of the pipe, and FIGS. 4 to 6 are front views showing different usage examples of the present invention. 10... Bearing body 11.11'... Raceway surface 14... Female thread 70
．． 70'...Railway 71.71'...Ball raceway surface 80...Female screw shaft Agent Lawyer Patent attorney Ukiko Kinoshita and 2 others Figure 2 Figure 3 Procedural amendment July 16, 1986

Claims (1)

[Claims] A bearing body having a female thread that is threadedly engaged with a male screw shaft through the balls of a ball screw has a ball raceway surface on both outward facing end surfaces, and a ball raceway surface provided on a track arranged on the outside of the bearing body. A ball bearing for linear motion that features a ball sandwiched between the two.