JPH0544724A - Rectilinear motion type guide device - Google Patents

Abstract

PURPOSE:To improve rectilinear moving property and prevent vibration by providing recessed parts on the inner faces in the front and rear direction of end cap parts, providing guide parts connected to the recessed parts of the end cap parts on the inner faces in the front and rear direction of the middle parts of a moving body, and forming guide grooves to connect the outward trip and the return trip of rolling elements out of the recessed parts and the guide parts. CONSTITUTION:A moving body 2 is constituted of end cap parts 4 and a middle part 5, and the respective parts 4, 5 are formed with leg-shaped parts 6, 7. Circular-arc-like recessed parts 17 are formed on the inside faces in the front and rear direction of the end cap parts 4. On the inner circumferential faces of the recessed parts 17, ball guide grooves 19 connected to the ball guide grooves 11 of ball outward trip 12 are formed. Meanwhile, semi-columnar guide parts 23 are formed on the front and rear both ends of the leg-shaped parts 7 of the middle part 5, and ball guide grooves 11 and ball guide grooves 20 of ball return trip 13 are formed. When the end cap parts 4 and the middle part 5 arc joined together, reversal passages 14 are formed out of the ball guide parts 23 and the ball guide grooves 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct drive type guide device,
More specifically, the present invention relates to a linear guide device including a linear guide rail and a moving body that moves across the guide rail and has a substantially inverted U-shaped cross section.

In this specification, front and rear, left and right refer to the moving direction of the moving body.

[0003]

2. Description of the Related Art Conventionally, as a linear motion type guide device of this type, as shown in FIG. 6, a movable body (51) moving across a guide rail (50) has end cap portions (52) at front and rear ends.
And the remaining middle part (53), the guide rail (5
Ball guide grooves (54) (55) on both sides of (0) and on the sides of the leg (53a) on both sides of the intermediate part (53) of the moving body (51) facing both sides of the guide rail (50), respectively. Is formed,
A ball outward path (56) is formed by both ball guide grooves (54) and (55), and a ball return path (57) is formed in each of the leg portions (53a) on both sides of the intermediate portion (53), and the ball outward path (56) is formed. And the end of the ball return path (57) are connected by the reversal path (58) formed at both ends of the moving body (51) to form a ball circulation path (59). ), The moving body (51) and the guide rail.
A plurality of balls (60) rolling between (50) are enclosed, and an inversion path (58) is provided with an arc-shaped recess (61) formed in the end cap portion (52) and an end cap. A guide member (62) having a semicircular cross section formed separately from the portion (52) and the intermediate portion (53) and attached to the end cap portion (52) so as to be located in the recess (61); Are known.

[0004]

However, in the conventional direct-acting guide device, dimensional error in manufacturing the end cap portion (52), the intermediate portion (53) and the guide member (62),
Due to these assembly errors, the end cap part (52)
And the intermediate portion (53) and between the intermediate portion (53) and the guide member (62) may have a step (A). Therefore, when the moving body (51) moves, the ball (60) is
The rolling resistance of the ball (60) in this part becomes large and the operating resistance of the moving body (51) becomes large, or the rolling resistance rapidly changes, and as a result, the moving body (51) There is a problem that the straightness of () is impaired or the moving body (51) is vibrated.

An object of the present invention is to provide a direct-acting guide device that solves the above problems.

[0006]

A direct-acting guide device according to the present invention comprises a linear guide rail and a moving body having a substantially inverted U-shaped cross section and moving across the guide rail. Is formed by the end cap portions at the front and rear ends and the remaining intermediate portion, and rolling element guide grooves are provided on both side surfaces of the guide rail and on the sides of the leg portions on both sides of the moving body that face both side surfaces of the guide rail. The rolling element guide groove forms the rolling element forward path, and the rolling element return paths are formed in the leg-shaped portions on both sides of the moving body, respectively, and the end of the rolling element forward path and the end of the rolling element return path are formed in the moving body. A rolling element circulation path is formed by being connected by inversion paths formed at both ends of the rolling element circulation path of the moving body, and a plurality of rolling elements rolling between the moving body and the guide rail are enclosed in the rolling element circulation path. Direct acting type guide device The inversion path is composed of a recess formed on the inner surface of the end cap portion in the front-rear direction and guide portions integrally formed at both front and rear ends of the intermediate portion of the moving body and arranged in the recess of the end cap portion. Has been done,
Rolling element guide grooves that connect the rolling element outward path and the rolling element return path are formed in the recess and the guide portion, respectively.

[0007]

The guide portion is formed integrally with the recess formed on the inner surface of the end cap portion in the front-rear direction and the front and rear end portions of the intermediate portion of the movable body, and is disposed in the recess of the end cap portion. When a rolling element guide groove that connects the rolling element forward path and the rolling element return path is formed in the recess and the guide portion, respectively, the rolling element forward path and the reversing path, and the rolling element return path. There is no step between the and the inversion path.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

1 to 4 showing the structure of a linear motion guide device according to the present invention, the linear motion guide device comprises a linear guide rail (1) and a cross section that moves across the guide rail (1). It is composed of a substantially U-shaped moving body (2).

Ball guide grooves (3) each having two arc-shaped portions are formed on both left and right side surfaces of the guide rail (1).

The movable body (2) comprises end cap portions (4) at the front and rear ends, and a remaining intermediate portion (5), and each of these portions has leg-shaped portions (6) (7) on both the left and right sides. ) And the leg parts (6) and (7) on the left and right sides are connected to each other.
It consists of (8) and (9). Legs on both left and right sides of the middle part (5)
A ball guide groove (11) consisting of two arc-shaped portions facing the ball guide groove (3) is formed on each of the surfaces of the guide rail (1) facing the left and right side surfaces of the guide rail (1). The ball guide groove (3) of the guide rail (1) and the
A ball forward path (12) is formed by the ball guide groove (11) in the intermediate portion (5) of (2). Further, straight hole-like ball return paths (13) are formed in the left and right leg-shaped portions (7) of the intermediate portion (5) of the moving body (2), respectively. And the ball going out
The end of (12) and the end of the ball return path (13) are connected by the reversal path (14) formed at both ends of the moving body (2) to form the endless ball circulation path (15). There is. Each ball circuit (15)
A plurality of balls (16) are enclosed in the. Ball (16)
Are both ball guide grooves (3) (11) in the ball outward path (12).
It comes in contact with each arc-shaped part of.

An arcuate recess (17) is formed on a surface of the end cap portion (4) which faces inward in the front-rear direction. Further, the left and right legs of the end cap portion (4) (6) are integrally formed with a protruding portion (18) protruding inward in the front-rear direction on the outer end portion in the front-rear direction on the inward-rear surface. There is. Recess
One end of the inner peripheral surface of (17) has a ball guide groove for the ball outward path (12).
A ball guide groove (19) connected to (11) is formed, and one end is connected to the ball guide groove (19) of the recess (17) and the other end is formed on the left and right inward surface of the protruding portion (18). The protruding portion (18)
A straight ball guide groove (20) extending to the tip of is formed.

A protrusion is formed at a portion which is laterally outside the ball return path (13) at both left and right ends of the left and right leg-shaped portions (7) of the intermediate portion (5) and at a height corresponding to the ball return path (13). A notch (21) is formed in which the portion (18) fits. Also,
Semi-cylindrical guide portions (22) are integrally formed on the front and rear end surfaces of the left and right leg portions (7) of the intermediate portion (5). Guide part
On the cylindrical surface of (22), one end is connected to the ball guide groove (11) and the other end is connected to the ball return path (13).
3) has been formed. And the end cap part (4)
The protruding part (18) of is fitted in the notch (21),
The guide part (22) of (5) is fitted in the recess (17), and it is formed by the ball guide groove (23) of the guide part (22) and the ball guide groove (19) of the recess (17). A ball reversal path (14) is formed. The ball guide groove (20) of the protruding part (18) is
It forms part of 3).

Each ball guide groove (11) of the intermediate portion (5)
As shown in FIG. 5, the notch (23) and the notch (21) are provided with a rotary shaft (2
4) is formed by using a circular grindstone (S) oriented in the vertical direction and performing a grinding process by an NC machine tool.
The locus of movement of the rotation axis of the grindstone (S) at this time is as shown by the curve X in FIG.

When the moving body (2) is moved along the guide rail (1), the ball (16) in the ball outward path (12) is moved by the moving body (2).
With the movement of (2), it rolls on the ball guide grooves (3) and (11) of the rail (1) and the intermediate part (5), and the moving direction of the moving body (2) with respect to the moving body (2). Move behind. For this reason, the ball (16) on the forward path (12) is sequentially reversed at the rear end of the moving direction.
The ball (16) on the reverse path (14) enters the ball return path (13) in order, and the ball (16) on the return path (13) enters the reverse path (14) at the front end in the moving direction in order. Take the outbound path (15). Thus, the ball (16) circulates in the ball circulation path (15).

In the above, there is a step at the boundary between the tip of the ball guide groove (20) of the projecting portion (18) of the end cap portion (4) and the front and rear end portions of the outer portion of the ball return path (13). Even if it does, the balls (16) passing through this boundary and the balls (16) located in front of and behind it will be lined up in a straight line. Therefore, the ball (16) passing through the boundary portion receives a force in the front-rear direction in the opposite direction to the ball (16) existing in the front-rear direction, and the force outward in the left-right direction. There is no such thing. As a result, almost no inward lateral force is applied from the stepped portion, the ball (16) rolls smoothly even at the boundary portion, and the rolling resistance does not fluctuate abruptly at this portion. On the other hand, as shown in FIG. 6, when there is a step at the boundary between the end cap portion (52) and the intermediate portion (53), the ball (60) passing through this boundary and the balls before and after it.
It does not line up in a straight line with (60), but in an arc shape. Therefore, the ball (60) passing through the boundary is subjected to a lateral outward force, and as a result, a lateral inward force is also received from the step portion, and the rolling resistance is increased in this portion. It fluctuates rapidly.

In the above embodiment, the balls are used as the rolling elements, but rollers may be used instead of the balls. Further, in the above embodiment, the semi-cylindrical guide portion
(22) is formed on both front and rear end surfaces of the left and right leg-shaped portions (7) of the intermediate portion (5) so as to project outward in the front-rear direction, but is not limited to this, and the semi-cylindrical guide portion (22) is not limited to this. The tip of the cylindrical surface may be flush with the end surface of the leg portion (7). In this case, correspondingly the end cap part (4) and the intermediate part
Change the shape of the combination with (5) as appropriate.

[0018]

According to the linear motion type guide device of the present invention,
As described above, since there is no step between the rolling element forward path and the reversing path, and between the rolling element return path and the reversing path,
The operating resistance of the moving body can be reduced. Further, since the rolling resistance of the rolling element does not fluctuate abruptly, the straightness of the moving body is prevented from being impaired and the moving body is prevented from vibrating.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view showing an embodiment of a direct acting guide device of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a partially enlarged view of FIG.

FIG. 4 is an exploded perspective view of a moving body.

FIG. 5 is a diagram showing a method of forming a ball guide groove and a notch in an intermediate portion of a moving body.

FIG. 6 is a view corresponding to FIG. 3 showing a conventional example.

[Explanation of symbols]

 1 guide rail 2 moving body 3 ball guide groove 4 end cap part 5 middle part 7 leg part 11 ball guide groove 12 ball forward path 13 ball return path 14 ball reversing path 15 ball circulation path 16 ball 17 recess 19 ball guide groove 22 guide Part 23 Ball guide groove

Claims (1)

[Claims] 1. A linear guide rail and a movable body having a substantially inverted U-shaped cross section that moves across the guide rail, wherein the movable body includes end cap portions at both front and rear ends and a remaining intermediate portion. The rolling element guide grooves are formed on both sides of the guide rail and on the sides of the leg portions on both sides of the moving body that face the both sides of the guide rail, respectively, and the rolling element forward grooves are formed by both rolling element guide grooves. The rolling element return path is formed on each of the leg portions on both sides of the moving body, and the end of the rolling element forward path and the end of the rolling element return path are connected by the reversing paths formed at both ends of the moving body. In a direct-acting type guide device in which a moving body circulation path is formed and a plurality of rolling elements rolling between the moving body and the guide rail are enclosed in the rolling body circulation path of the moving body, the reversing passage has an end cap. Formed on the inner surface in the front-back direction of the part And a guide portion that is integrally formed at both front and rear end portions of the intermediate portion of the moving body and that is disposed in the recess portion of the end cap portion. A direct-acting type guide device having a rolling element guide groove that connects an outward path and a rolling element return path.