JPS638330B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used for a linear guide bearing with an endless ball track, and prevents the balls from falling off when the bearing body is separated from the guide shaft. The present invention relates to a ball retainer that forms a part of an endless track of balls formed in a bearing body.

[Conventional technology]

Conventionally, this type of ball retainer was made by bending a metal plate into an appropriate shape and opening a long hole at a position opposite to the load ball groove formed in the bearing body when the metal plate was assembled into the bearing body. A part of the ball located in the loaded area of the endless track protrudes from this elongated hole toward the guide shaft side, and at both longitudinal ends of the elongated hole, the ball is fed from the unloaded area of the endless track to the loaded area, Alternatively, a device equipped with a tongue piece for scooping up and feeding from a load area to a non-load area is known, and a device made of synthetic resin has also been proposed.

[Problem that the invention seeks to solve]

However, although the former metal ball holder is satisfactory in that it has excellent rigidity and durability, it is particularly difficult for the balls to be scooped up from the loaded area to the no-load area. There was a problem in that when the ball collided with the tongue of the ball holder, a harsh metallic sound was generated, and this became a loud noise, especially during high-speed motion. In addition, the latter type of ball cage made of synthetic resin does not have such a problem of noise generation, but it is inferior in rigidity compared to metal ones, is easily distorted, and has problems in terms of durability. It was hot.

[Means for solving problems]

This invention was devised in view of this point of view, and takes advantage of the features of the metal ball holder, and also moves the balls from the load area to the no-load area or from the no-load area to the load area in the endless track of the balls. As a ball feeding mechanism, a ball feeding part is formed at both ends of the elongated hole in the longitudinal direction, and the width of the ball feeding part gradually decreases. A ball abutment surface is formed that has a sloped part with the same curvature and a sloped part with a curvature that is approximately equal to the curvature of the ball at a portion facing each other, thereby allowing the ball to move from the loaded area to the no-load area to The ball is gradually lifted from the groove and fed into the guide groove, and the ball moving from the no-load area to the loaded area is gradually fed into the loaded ball groove from the guide groove to prevent metallic noise between the ball and the ball holder. To provide a ball holder that can prevent the occurrence of such occurrence and further smoothly circulate the balls from the load area to the no-load area or from the no-load area to the load area of the endless track.

That is, the present invention has a guide shaft having a ball rolling groove along the axial direction, and a loaded ball groove and an unloaded ball groove that form an endless track for the ball rolling in the rolling groove, A bearing body that performs linear reciprocating motion along the guide shaft via a ball, and a bearing body that is attached to both end faces of this bearing body,
A ball holder for a linear guide bearing comprising a pair of side covers having guide grooves for guiding the balls between the loaded ball groove and the unloaded ball groove, and the ball holder includes a ball holder formed on the bearing body. An elongated hole is formed to form a load area of the endless track facing the loaded ball groove and to make a part of the ball protrude toward the guide shaft side. A ball feeding section is formed whose dimensions gradually decrease from the load area to the no-load area of the endless track formed on the bearing body side, or from this no-load area to the load area, and this ball feeding section is formed. On the opening edge of the recessed part, a ball abutment is provided, which has a sloped part with a curvature approximately equal to the curvature of the guide groove so as to be continuous with the guide groove of the side cover, and a sloped part with a curvature approximately equal to the curvature of the ball at the mutually opposing parts. This is a ball retainer for a linear guide bearing that forms a contact surface.

In this invention, the width of the ball feed portions formed at both ends of the elongated hole gradually decreases toward the ends, so that when the ball moves along the elongated hole, it It may have any shape as long as it can send the ball to the no-load area side or in the opposite direction, but it is preferably formed into a semi-elliptical shape.

In addition, the ball contact surface formed in the ball feeding part of the elongated hole receives the ball on the slope part and feeds the ball from the load ball groove to the guide groove of the side cover or from the guide groove to the load ball groove. , preferably formed of a sloped portion having a curvature approximately equal to the curvature of the guide groove of the side cover and continuous to the guide groove of the side cover, and a sloped portion having a curvature approximately equal to the curvature of the ball at mutually opposing portions. It is better to reduce the width of the ball feeding portion as gently as possible.

Furthermore, the bearing that can be used with the ball holder of the present invention may be any linear guide bearing with an endless track of balls, and even if it is a linear ball bearing that only guides movement in the axial direction, It may be a linear sliding ball bearing of a type that can load a load in one direction or a ball spline.

[Effect]

In the ball holder of the present invention, the balls are gradually lifted up and fed from the loaded area of the endless track to the unloaded area by the ball feeding parts formed at both longitudinal ends of the elongated hole. Since the ball is supported by the ball contact surface,
The movement of the ball from the load area to the no-load area or from the no-load area to the load area becomes smooth.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

1 to 5 show a ball holder according to the present invention, and the ball holder 10 includes a holder base 12 whose side surface is approximately rectangular and whose cross section is bent into an approximately trapezoidal shape; Both flange portions 14 extend from both sides of the cage base 12 at a certain angle (right angles are shown in the drawing), and both side portions 16 of the cage base 12 are provided.
An elongated hole 11 is formed in the bearing body 20 to form a load area of the endless track 24 opposite to a load ball groove 22 formed in the bearing body 20, which will be described later, and to cause a part of the ball 50 to protrude toward the guide shaft side. In this case, at both longitudinal ends of the elongated hole 11, the width dimension gradually decreases to transfer the load from the load area to the no-load area of the endless track formed on the bearing body side, or from this no-load area. A ball feeding section 13 for guiding the ball 50 is formed in the area. At the opening edge of the ball feeding portion 13, there is a sloped portion 15a having a curvature approximately equal to the curvature of the guide groove 32 so as to be continuous with the guide groove 32 of the side cover 30, and a slope portion 15a having a curvature approximately equal to that of the guide groove 32, and a curvature of the ball 50 at a portion facing each other. A ball contact surface 15 is formed with a slope portion 15b having approximately the same curvature. Further, a tapered surface 17 is formed at the mutually parallel opening edge between the ball feeding portions 13 and 13 of the long hole 11, so that the entire circumference of the opening edge of the long hole 11 is formed in a continuous taper shape. .

The ball feeding section 13 configured in this way is
As shown in FIGS. 4 and 5, the width becomes smaller as it approaches the end, and when the ball 50 moves along the elongated hole 11, the ball 50
0 can be gradually lifted up and smoothly fed into the guide groove 30 via the slope portion 15a of the ball contact surface 15, thereby allowing the ball to move from the load area side of the endless track to the no-load area side. 50 circulation becomes smoother.
Further, since the slope portion 15b of the ball contact surface 15 has a curvature that is approximately equal to the curvature of the ball 50, the degree of narrowing of the opening width of the elongated hole 11 can be made as gentle as possible, and the degree of narrowing of the opening width of the long hole 11 can be made as gentle as possible. Feeding can be made even smoother.

The ball holder 10 of the present invention configured as described above is incorporated into a bearing body 20 as shown in FIGS. This prevents the ball 50 that carries a load from falling off and forms an endless track for the ball 50. In this case, as shown in FIG. 12, the bearing main body 20 is formed into a substantially U-shape with a groove 21 on the lower surface, and is slidably fitted onto the upper part of the track 40, which is a guide shaft. Furthermore, on the inner surface of the groove 21, there are two load ball raceways each having an arcuate cross section and facing the upper load ball rolling surfaces 42 formed on both sides of the upper part of the track 40. A raceway surface 23 is formed, and on the back side of each ball raceway surface 23, a no-load ball hole 25 constituting a no-load ball groove is bored along the guide shaft direction. In this case, escape slopes for movement of the balls 50 are formed at both front and rear ends of the loaded ball rolling surface 23 at portions facing the ball feeding portion 13 of the ball holder 10. A large number of balls 50 are installed in the ball retainer 10 of the present invention in the two load ball grooves 22 formed by the mutually opposing raceway surfaces 23 and 42 of the bearing body 20 and the track 40 configured as described above. It is arranged through.

Furthermore, side covers 30 are fixed to the front and rear end surfaces of the bearing body 20 with bolts 31. As shown in FIGS. 14 and 15, this side cover 30 is formed to have almost the same cross-sectional shape as the bearing body 20, and the load ball groove 22, Four guide grooves 32 extending approximately in the radial direction are formed which connect the ball grooves 22 to the no-load ball grooves 25, 25, respectively. Furthermore, a locking groove 34 for locking the ball holder 10 is formed on the inner surface of the recess 33 of the side cover 30. Note that reference numeral 35 indicates an axial lubricating oil supply hole drilled in each side cover 30;
36 is an oil groove connecting the oil supply hole 35 and the guide groove 32;
7 is an insertion hole for the bolt 31.

Since it is necessary to ensure that the balls 50 can roll smoothly at the joint between the side cover 30 and the bearing body 20 configured in this manner, as shown in FIG. Arc-shaped chamfered portions 26 are provided on the edges of the loaded ball rolling surface 23 and the unloaded ball hole 25 at the ends (see FIG. 13), and these chamfered portions 26 are provided on the side cover 30. A matching arc-shaped chamfer 38 is provided (see FIGS. 16 and 17).

As shown in FIG. 18, the track 40 has V-shaped grooves 44 formed on both sides of the rectangular portion, and upper load ball rolling surfaces 42 on the upper and lower surfaces of both upper shoulders. and a lower load ball rolling surface 43, and mounting bolt holes 45 for mounting to a bed (not shown) are bored at appropriate intervals.

The ball retainer 1 of the present invention is attached to the bearing body 20 of the linear guide bearing configured as described above.
0 to form an endless track for the balls 50, the elongated hole 1 opened in the ball holder 10
Ball feeding portion 1 formed at both ends in the longitudinal direction of 1
3 gradually lifts the ball 50 from the load area to the no-load area of the endless track, or from the no-load area to the load area, and at this time, the ball 50 is moved to the above-mentioned slope portion 15a, 15b
Since the ball is supported by the ball abutting surface 15 having a diameter, the ball can be smoothly moved between the load area and the no-load area. In addition, the bearing body 2
0 is separated from the track 40, the ball 5
0,50... can be prevented from falling off.

The ball holder of the present invention can be used as a bearing as long as it is a linear guide bearing with an endless track of balls, and even if it is a linear ball bearing that only guides movement in the axial direction, It goes without saying that the same effect can be obtained with a linear sliding ball bearing that can bear a load in any direction or with a ball spline.

〔Effect of the invention〕

As explained above, according to the ball holder of the present invention, the mechanism for feeding the balls from the load area to the no-load area in the endless track of the balls, or from the no-load area to the load area, is provided in the longitudinal direction of the elongated hole. A ball feeding part is formed at both ends and the width dimension gradually decreases, and this ball feeding part has a sloped part with a curvature approximately equal to the curvature of the guide groove and a sloped part facing each other so as to be continuous with the guide groove of the side cover. Since the ball contact surface is formed of a sloped surface with a curvature approximately equal to the curvature of the ball at the part facing the ball, it takes advantage of the features of the metal ball holder and also improves the relationship between the ball and the ball holder. In addition, the ball feeding section gradually lifts the ball and feeds it from the load area of the endless track to the no-load area, and at this time the ball is moved to the side. Since the ball is supported by a ball contact surface that has a sloped surface with a curvature approximately equal to the curvature of the guide groove of the lid and a sloped surface with a curvature approximately equal to the curvature of the ball, the circulation of the ball between the load area and the non-load area of the endless track is prevented. Since excellent effects such as being able to perform the process even more smoothly can be obtained, its utility value is remarkable.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an example of the ball retainer of the present invention, Fig. 2 is an enlarged perspective view of the main part thereof, Fig. 3 is a sectional view of Fig. 2, and Fig. 4 is a main part of Fig. 2. A plan view, FIG. 5 is a sectional view of FIG. 4, and FIG. 6 is a front view of the ball retainer of the present invention in an installed state.
Figures 7 to 9 are a front sectional view, side view, and plan view of Figure 6, respectively, and Figure 10 is a view of Figure 7.
The sectional view, Fig. 11, is the A arrow direction view of Fig. 10, 1st
Figure 2 is a front view of the bearing body, Figure 13 is the first
Figure 2 is a sectional view, Figure 14 is a front view of the side cover,
15 is a cross-sectional view of FIG. 14, FIG. 16 is an enlarged cross-sectional end view of the main part of the side cover, FIG. 17 is a cross-sectional view of FIG. 16, and FIG. 18 is a perspective view of the track base. Description of symbols 10...Ball holder, 11...Elongated hole,
13...Ball feeding part, 15...Ball contact surface, 1
5a, 15b...Slope portion, 20...Bearing body,
22...Load ball groove, 50...Ball.

Claims (1)

[Claims] 1 Rolling grooves 42, 4 of the ball 50 along the axial direction
3, and the rolling grooves 42, 43.
The bearing body 20 has a loaded ball groove 22 and an unloaded ball groove 25 forming an endless track for the balls 50 rolling on the bearing body 20, and performs linear reciprocating motion along the guide shaft 40 via the balls 50. A pair of side covers 3 that are attached to both end faces of the bearing body 20 and have guide grooves 32 for guiding the balls 50 between the loaded ball groove 22 and the unloaded ball groove 25.
0, and the ball 50 retainer has a load area of the endless track facing the load ball groove 22 formed in the bearing main body 20, and the ball 50 retainer has the above-mentioned A long hole 11 is formed through which a part of the ball 50 projects toward the guide shaft side, and a long hole 11 is formed at both ends of the long hole 11 in the longitudinal direction, the width of which gradually decreases from the load area to the bearing body side. A ball feeding part 13 is formed in the no-load area of the endless track or from this no-load area to the loaded area, and the opening edge of this ball feeding part 13 is provided with a guide groove of the side cover 30. The ball abutting surface 15 is formed to have an inclined surface 15a having a curvature approximately equal to the curvature of the guide groove 32 so as to be continuous with the guide groove 32, and an inclined surface 15b having a curvature approximately equal to the curvature of the ball 50 at a portion facing each other. A linear guide bearing ball retainer featuring: