US-12623852-B2 - Straight and curved guide rail and straight and curved guide device

Abstract

A straight-curved guide rail includes a straight part and a curved part and is configured to guide movement of a movable element. The straight-curved guide rail includes: a base part extending in a longitudinal direction of the straight-curved guide rail; and a track part, which is formed on the base part, extends in the longitudinal direction, and has a pair of rail ends, each including a track surface to be in contact with the movable element, on both side portions of the straight-curved guide rail in a width direction of the straight-curved guide rail. A region of the straight-curved guide rail, which includes an end portion of the straight-curved guide rail in the longitudinal direction, includes a low-stiffness region in which portions including the track surfaces have lower stiffness than stiffness of other region.

Inventors

• Satoshi Sasaki
• Daisuke Sato
• Yuichi SHIBUYA

Assignees

• NIPPON THOMPSON CO., LTD.

Dates

Publication Date

20260512

Application Date

20221109

Priority Date

20211126

Claims (12)

1. 1 . A straight-curved guide rail which includes a straight part and a curved part and is configured to guide movement of a movable element, the straight-curved guide rail comprising: a base part extending in a longitudinal direction of the straight-curved guide rail; and a track part, which is formed on the base part, extends in the longitudinal direction, and has a pair of rail ends, each including a track surface to be in contact with the movable element, on both side portions of the straight-curved guide rail in a width direction of the straight-curved guide rail, wherein a region of the straight-curved guide rail, which includes an end portion of the straight-curved guide rail in the longitudinal direction, includes a low-stiffness region in which portions including the track surfaces have lower stiffness than stiffness of another region, the low-stiffness region extending in the longitudinal direction to an end surface of the end portion of the straight-curved guide rail.
2. 2 . The straight-curved guide rail according to claim 1 , wherein, in the low-stiffness region, the base part includes: a first base part having a smaller length in the width direction than a length of the track part in the width direction; and a second base part, which connects the first base part and the track part to each other and has a smaller length in the width direction than the length of the first base part in the width direction.
3. 3 . The straight-curved guide rail according to claim 2 , wherein the track part includes: a first track part that overlaps the base part in a height direction of the straight-curved guide rail; and a pair of second track parts, which are formed on both sides of the first track part in the width direction and include the pair of rail ends, wherein, in the low-stiffness region, the track part has a first cutout portion formed by cutting out a part of the track part from an end portion of the track part in the longitudinal direction so that the first track part and the second track parts are spatially separated from each other.
4. 4 . A straight-curved guide device, comprising: the straight-curved guide rail of claim 3 ; and a movable element being movable on the straight-curved guide rail.
5. 5 . The straight-curved guide rail according to claim 2 , wherein the track part includes: a first track part that overlaps the base part in a height direction of the straight-curved guide rail; and a pair of second track parts, which are formed on both sides of the first track part in the width direction and include the pair of rail ends, wherein, in the low-stiffness region, the track part has a second cutout portion formed by removing the first track part from an end portion of the track part in the longitudinal direction.
6. 6 . A straight-curved guide device, comprising: the straight-curved guide rail of claim 5 ; and a movable element being movable on the straight-curved guide rail.
7. 7 . A straight-curved guide device, comprising: the straight-curved guide rail of claim 2 ; and a movable element being movable on the straight-curved guide rail.
8. 8 . The straight-curved guide rail according to claim 1 , wherein the track part includes: a first track part that overlaps the base part in a height direction of the straight-curved guide rail; and a pair of second track parts, which are formed on both sides of the first track part in the width direction and include the pair of rail ends, wherein, in the low-stiffness region, the track part has first cutout portions, each being formed by cutting out a part of the track part from an end portion of the track part in the longitudinal direction so that the first track part and the second track parts are spatially separated from each other.
9. 9 . A straight-curved guide device, comprising: the straight-curved guide rail of claim 8 ; and a movable element being movable on the straight-curved guide rail.
10. 10 . The straight-curved guide rail according to claim 1 , wherein the track part includes: a first track part that overlaps the base part in a height direction of the straight-curved guide rail; and a pair of second track parts, which are formed on both sides of the first track part in the width direction and include the pair of rail ends, wherein, in the low-stiffness region, the track part has a second cutout portion formed by removing the first track part from an end portion of the track part in the longitudinal direction.
11. 11 . A straight-curved guide device, comprising: the straight-curved guide rail of claim 10 ; and a movable element being movable on the straight-curved guide rail.
12. 12 . A straight-curved guide device, comprising: the straight-curved guide rail of claim 1 ; and a movable element being movable on the straight-curved guide rail.

Description

TECHNICAL FIELD The present disclosure relates to a straight-curved guide rail and a straight-curved guide device including the straight-curved guide rail. This application claims priority from Japanese Patent Application No. 2021-191740, filed on Nov. 26, 2021, the contents of which are incorporated herein by reference in their entirety. BACKGROUND ART Hitherto, there has been known a guide device including a rail and a movable element being movable on the rail. This kind of technology is disclosed in, for example, Patent Literature 1 and Patent Literature 2. In Patent Literature 1 and Patent Literature 2, there is disclosed a linear guide device including a rail, a slider, and a plurality of rolling elements. The slider is linearly movable on the rail. The plurality of rolling elements are arranged between the rail and the slider. In the linear guide device disclosed in Patent Literature 1, a slit having a predetermined depth in a height direction of the rail extends in a longitudinal direction of the rail from an end portion of the rail in the longitudinal direction. In the linear guide device disclosed in Patent Literature 2, a slit is formed in an end portion of the rail in a longitudinal direction of the rail in such a manner as to extend throughout the rail in its height direction. CITATION LIST Patent Literature Patent Literature 1: JP 2014-163483 APatent Literature 2: JP 2016-166634 A Summary of Invention Technical Problem In the guide devices, a plurality of rails are arranged in line in the longitudinal direction, and end portions of the rails in the longitudinal direction are connected to each other. In this case, when processing accuracy differs greatly among the rails, there arises a problem in that a large shock may be generated when the movable element is moved from one rail to another rail. In particular, a straight-curved guide rail including a curved part is liable to have lower processing accuracy than processing accuracy of a straight rail having no curved part. An object of the present disclosure is to provide a straight-curved guide rail that enables suppression of a shock, which may be generated when a movable element is moved between a rail having low processing accuracy and a rail having high processing accuracy, and a straight-curved guide device including the straight-curved guide rail. Solution to Problem A straight-curved guide rail according to the present disclosure includes a straight part and a curved part and is configured to guide movement of a movable element. The straight-curved guide rail includes: a base part extending in a longitudinal direction of the straight-curved guide rail; and a track part, which is formed on the base part, extends in the longitudinal direction, and has a pair of rail ends, each including a track surface to be in contact with the movable element, on both side portions of the straight-curved guide rail in a width direction of the straight-curved guide rail. A region of the straight-curved guide rail, which includes an end portion of the straight-curved guide rail in the longitudinal direction, includes a low-stiffness region in which portions including the track surfaces have lower stiffness than stiffness of other region. A straight-curved guide device according to the present disclosure includes: the straight-curved guide rail; and a movable element being movable on the straight-curved guide rail. Advantageous Effects of Invention According to the present disclosure, the straight-curved guide rail that enables suppression of a shock, which may be generated when the movable element is moved between a rail having low processing accuracy and a rail having high processing accuracy, and the straight-curved guide device including the straight-curved guide rail can be provided. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a perspective view for illustrating a configuration of a straight-curved guide device according to a first embodiment. FIG. 2 is a view of the straight-curved guide device according to the first embodiment when viewed in a longitudinal direction of a straight-curved guide rail. FIG. 3 is a perspective view for illustrating a configuration of the straight-curved guide rail according to the first embodiment. FIG. 4 is a sectional view of the straight-curved guide rail, taken along the line IV-IV of FIG. 3. FIG. 5 is a perspective view for illustrating two straight-curved guide rails according to a second embodiment, which are arranged in line in the longitudinal direction. FIG. 6 is an enlarged view of the area VI of FIG. 5. FIG. 7 is a sectional view of the straight-curved guide rail, taken along the line VII-VII of FIG. 6. FIG. 8 is a perspective view for illustrating a configuration of a straight-curved guide rail according to the second embodiment. FIG. 9 is a view for illustrating two straight-curved guide rails according to a third embodiment, which are arranged in line in the longitudinal direction. FIG. 10 is a sectional view of t