Linear motion unit

Abstract

This linear motion unit includes a linear motion mechanism and a housing. The linear motion mechanism includes a track member and a movement member. The housing includes a cover member that covers the linear motion mechanism. The cover member includes a fastener extending in the longitudinal direction. The fastener includes a first element, a second element, a first slider, and a second slider. The first slider and the second slider cause the first element and the second element to separate from each other as each moves in a direction away from the side where the other is positioned, and cause the first element and the second element to mesh with each other as each moves in a direction toward the side where the other is positioned. The first slider and the second slider can be fixed to the movement member. The fastener reaches at least one end of the cover member in the longitudinal direction. One end of the cover member is configured to be openable and closable.

Description

Linear motion unit

[0001] This disclosure relates to a linear motion unit. This application claims priority to Japanese Application No. 2023-197182, filed November 21, 2023, and incorporates by reference all of the contents of said Japanese application.

[0002] Conventionally, linear motion units in which a linear motion mechanism is housed in a housing for the purpose of dustproofing and waterproofing have been known. This type of technology is described, for example, in Patent Document 1 and Patent Document 2. Patent Document 1 discloses a linear motion unit in which a ball screw, which is a linear motion mechanism, is housed in a housing. In this document, the housing is formed by combining a bottom plate in which the ball screw is disposed, a pair of side plates, and a top plate.

[0003] JP 2000-230618 A JP 2017-109580 A

[0004] In a linear motion unit that houses a linear motion mechanism in a housing, a fastener may be provided on a cover member that covers the linear motion mechanism. This configuration makes it easy to ensure high sealing performance in the housing. However, there are cases where the cover member must be replaced before the linear motion unit reaches the end of its life. If the replacement requires a large number of steps, the replacement work becomes cumbersome. There is a demand for improved operability when replacing the cover member. Therefore, one of the objectives is to provide a linear motion unit that can improve operability when replacing the cover member.

[0005] A linear motion unit according to the present disclosure includes a linear motion mechanism and a housing that houses the linear motion mechanism. The linear motion mechanism includes a track member and a moving member that is linearly movable along the longitudinal direction of the track member. The housing includes a cover member that covers the linear motion mechanism. The cover member includes a fastener extending in the longitudinal direction. The fastener includes a first element extending in the longitudinal direction, a second element that extends in the longitudinal direction along the first element and is engageable with the first element, a first slider attached to the first element and the second element, and a second slider attached to the first element and the second element and positioned spaced apart from the first slider in the longitudinal direction. The first slider and the second slider move the first element and the second element apart as they move in a direction away from the side where the other element is located, and engage the first element and the second element as they move toward the side where the other element is located. The first slider and the second slider are fixable to the moving member. The fastener extends to at least one of the longitudinal ends of the cover member, the one end of which is configured to be openable and closable.

[0006] According to the linear motion unit, the workability when replacing the cover member can be improved.

[0007] FIG. 1 is a schematic perspective view of a linear motion unit according to a first embodiment of the present disclosure. FIG. 2 is a schematic perspective view of the linear motion unit shown in FIG. 1 with a cover member, described later, removed. FIG. 3 is a schematic plan view of the linear motion unit shown in FIG. 1. FIG. 4 is a schematic side view of the linear motion unit shown in FIG. 1. FIG. 5 is a schematic front view of the linear motion unit shown in FIG. 1. FIG. 6 is a schematic cross-sectional view of the linear motion unit shown in FIG. 1. FIG. 7 is a schematic perspective view showing a state in which a front wall portion is released. FIG. 8 is a schematic perspective view showing a state in which a cover member is being pulled out. FIG. 9 is a schematic perspective view of a linear motion unit according to a second embodiment of the present disclosure. FIG. 10 is a schematic side view of a cover member included in the linear motion unit shown in FIG. 9. FIG. 11 is a schematic perspective view showing a state in which a cover member included in the linear motion unit shown in FIG. 9 is removed. FIG. 12 is a schematic perspective view showing a state in which a cover member is being pulled out. FIG. 13 is a schematic perspective view of a linear motion unit according to a third embodiment of the present disclosure. FIG. 14 is a schematic perspective view showing a state in which a front wall portion is released. FIG. 15 is a schematic perspective view showing a state in which the cover member is being pulled out.

[0008] [Summary of the embodiment] A linear motion unit according to the present disclosure includes a linear motion mechanism and a housing that houses the linear motion mechanism. The linear motion mechanism includes a track member and a moving member that is linearly movable along the longitudinal direction of the track member. The housing includes a cover member that covers the linear motion mechanism. The cover member includes a fastener extending in the longitudinal direction. The fastener includes a first element that extends in the longitudinal direction, a second element that extends in the longitudinal direction along the first element and is engageable with the first element, a first slider attached to the first element and the second element, and a second slider attached to the first element and the second element and positioned spaced apart from the first slider in the longitudinal direction. The first slider and the second slider move the first element and the second element apart as they move in a direction away from the side where the other element is located, and engage the first element and the second element as they move toward the side where the other element is located. The first slider and the second slider are fixable to the moving member. The fastener extends to at least one of the longitudinal ends of the cover member, the one end of which is configured to be openable and closable.

[0009] According to the linear motion unit of the present disclosure, when removing the cover member from the linear motion unit, such as when replacing the cover member, one end of the cover member is opened and the cover member is pulled toward the other end. Since the fastener reaches one end of the cover member, the cover member can be pulled out as is. Therefore, the cover member can be removed from the linear motion unit without removing the moving member to which the first slider and the second slider are fixed. As a result, when removing the cover member, the process of removing and reattaching the moving member can be omitted. As described above, this linear motion unit can improve the workability when replacing the cover member.

[0010] In the linear motion unit, the fastener may extend to both longitudinal ends of the cover member. The both longitudinal ends of the cover member may be configured to be openable and closable. This allows the cover member to be removed from the linear motion unit by pulling it out from both longitudinal ends. This improves the convenience of replacing the cover member.

[0011] In the linear motion unit, the cover member may include a side wall portion located on a side surface of the linear motion mechanism, an upper wall portion connected to the side wall portion and having a fastener provided thereon and located above the linear motion mechanism, a front wall portion located at one end in the longitudinal direction, and a rear wall portion located at the other end in the longitudinal direction. At least one of the front wall portion and the rear wall portion may be configured to be openable and closable. This allows the side wall portion, the upper wall portion, the front wall portion, and the rear wall portion to surround the linear motion mechanism, and the cover member can be pulled out from either the front wall portion or the rear wall portion. This allows the linear motion mechanism to be more appropriately covered by the cover member while improving operability and enhancing the dustproofness of the linear motion mechanism.

[0012] In the linear motion unit, at least one of the front wall portion and the rear wall portion may be configured by bending a first longitudinal end region of the top wall portion and a second longitudinal end region of the side wall portion. By configuring at least one of the front wall portion and the rear wall portion in this manner, the above-mentioned openable and closable configuration can be easily realized, thereby further improving workability.

[0013] In the linear motion unit, a plurality of fasteners may be provided at intervals in a direction intersecting the longitudinal direction. In this way, even when a plurality of fasteners are used, the cover member can be easily removed, thereby improving workability.

[0014] In the linear motion unit, the raceway member may be formed with a first rolling surface extending in the longitudinal direction. The moving member may be formed with a second rolling surface opposing the first rolling surface and forming a rolling element rolling path between the first rolling surface and the second rolling surface. The linear motion mechanism may further include a plurality of rolling elements that circulate in a rolling element circulating path including the rolling element rolling path as the moving member moves linearly in the longitudinal direction of the raceway member. Such a linear motion mechanism can smoothly move the moving member by utilizing the plurality of rolling elements.

[0015] In the linear motion unit, the linear motion mechanism may include a triangular screw, a trapezoidal screw, a square screw, or a ball screw. Such a linear motion mechanism can move the moving mechanism by rotating the screw shaft with a motor or the like, and can be effectively used in an actuator or the like.

[0016] In the linear motion unit, the housing may include a base plate. The cover member may be attached to the base plate. The linear motion mechanism may be disposed in a space surrounded by the cover member and the base plate. In this manner, the base plate and the cover member can easily seal the linear motion mechanism. Therefore, dust resistance can be improved.

[0017] [Specific Example of Embodiment] Next, an example of a specific embodiment of the linear motion unit of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0018] (Embodiment 1) First, a first embodiment of the present disclosure will be described. FIG. 1 is a schematic perspective view of a linear motion unit according to the first embodiment of the present disclosure. FIG. 2 is a schematic perspective view of the linear motion unit shown in FIG. 1 with a portion of a cover member, which will be described later, removed. FIG. 3 is a schematic plan view of the linear motion unit shown in FIG. 1. FIG. 3 is a view of the linear motion unit shown in FIG. 1 as viewed in the direction indicated by arrow III. FIG. 4 is a schematic side view of the linear motion unit shown in FIG. 1. FIG. 4 is a view of the linear motion unit shown in FIG. 1 as viewed in the direction indicated by arrow IV. FIG. 5 is a schematic front view of the linear motion unit shown in FIG. 1. FIG. 5 is a view of the linear motion unit shown in FIG. 1 as viewed in the direction indicated by arrow V. FIG. 6 is a schematic cross-sectional view of the linear motion unit shown in FIG. 1. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 1. In Figure 1 and the following figures, the X direction indicates the longitudinal direction of the linear motion unit, the Y direction indicates the lateral direction, i.e., the width direction of the linear motion unit, and the Z direction indicates the thickness direction (height direction) (up and down direction) of the linear motion unit. The X direction, Y direction, and Z direction are perpendicular to each other. The direction indicated by the arrow X is from the rear side to the front side. In addition, in Figure 2, a fastener, which will be described later, is also shown to facilitate understanding.

[0019] 1 , 2 , 3 , 4 , 5 , and 6 , linear motion unit 10 a according to the first embodiment of the present disclosure includes linear motion mechanism 11 a and a housing 41 a that houses linear motion mechanism 11 a. In the present embodiment, linear motion unit 10 a is configured from linear motion mechanism 11 a and housing 41 a.

[0020] The linear motion mechanism 11a includes a rail 12a as a track member and a slide block 13a as a moving member attached to the rail 12a. The slide block 13a is movable linearly along the longitudinal direction of the track member. The rail 12a extends linearly in the longitudinal direction (X direction). The rail 12a has a plurality of circular through-holes that penetrate in the thickness direction (Z direction). The plurality of through-holes are spaced apart in the longitudinal direction. These through-holes are used for mounting the linear motion unit 10a, etc.

[0021] A pair of first raceway surfaces 21a, 22a are provided on both sides of the rail 12a in the width direction (Y direction). Each of the first raceway surfaces 21a, 22a extends in the longitudinal direction over the entire rail 12a.

[0022] The slide block 13a is movable linearly along the longitudinal direction of the rail 12a. Referring particularly to Fig. 2, the slide block 13a includes a casing 23a and a pair of end caps (first end cap 24a and second end cap 25a) disposed on either side of the casing 23a in the longitudinal direction. The casing 23a includes a casing main body 26a extending in the width direction and a pair of sleeves (first sleeve 27a and second sleeve 28a) extending in the thickness direction from either side of the casing main body 26a.

[0023] The first sleeve portion 27a extends vertically from one widthwise end of the casing body 26a toward the rail 12a. The first sleeve portion 27a has a second rolling surface 31a that faces the first rolling surface 21a and forms a first rolling element rolling path 33a between the first rolling surface 21a and the second rolling surface 31a. The second rolling surface 31a is formed in an area of ​​the first sleeve portion 27a that faces the rail 12a. A plurality of rolling elements, specifically balls 15a, are arranged longitudinally in the first rolling element rolling path 33a. Note that the type of rolling elements is not limited to balls and may be, for example, rollers.

[0024] A first return path 29a is formed in the first sleeve portion 27a. The first return path 29a extends along the first raceway surface 21a. The first return path 29a is a circular through-hole that passes through the first sleeve portion 27a in the longitudinal direction. The first return path 29a is formed at a position farther away from one end of the casing body 26a than the second raceway surface 31a.

[0025] The second sleeve portion 28a extends in the height direction from the other widthwise end of the casing body 26a toward the rail 12a. The second sleeve portion 28a is formed with a second raceway surface 32a that faces the first raceway surface 22a and forms a second rolling element rolling path 34a between the second sleeve portion 28a and the first raceway surface 22a. The second raceway surface 32a is formed in an area of ​​the second sleeve portion 28a that faces the rail 12a. A plurality of rolling elements, specifically balls 15a, are arranged longitudinally in the second rolling element rolling path 34a.

[0026] A second return path 35a is formed in the second sleeve portion 28a. The second return path 35a extends along the first raceway surface 22a. The second return path 35a is a circular through-hole that passes through the second sleeve portion 28a in the longitudinal direction. The second return path 35a is formed at a position farther away from the other end of the casing body 26a than the second raceway surface 32a.

[0027] The first end cap 24a is formed with a first direction change path (not shown) connecting the first rolling element rolling path 33a and the first return path 29a, and a second direction change path (not shown) connecting the second return path 35a and the second rolling element rolling path 34a. Similarly, the second end cap 25a is formed with a first direction change path (not shown) connecting the first rolling element rolling path 33a and the first return path 29a, and a second direction change path (not shown) connecting the second return path 35a and the second rolling element rolling path 34a.

[0028] A first annular rolling element circulation path is formed inside the slide block 13a, and the first rolling element rolling path 33a, the first return path 29a, and the first direction change path are included. Also, a second rolling element circulation path is formed inside the slide block 13a, and the second rolling element circulation path is formed inside the slide block 13a, and the second rolling element circulation path is formed, and the second rolling element rolling path 34a, the second return path 35a, and the second direction change path are included. As the slide block 13a moves linearly along the longitudinal direction of the rail 12a, the plurality of balls 15a circulate through the first rolling element circulation path and the second rolling element circulation path.

[0029] In this embodiment, the housing 41a has a rectangular parallelepiped shape that is long in the longitudinal direction. The housing 41a is box-shaped and includes a base plate 42a, a cover member 43a, and a stay member 44a.

[0030] The base plate 42a has a plate shape extending in the longitudinal direction. The base plate 42a has a flat plate shape. The base plate 42a has a rectangular shape that is long in the longitudinal direction when viewed in the thickness direction. The stay member 44a is disposed on the base plate 42a. The stay member 44a has a shape that extends in the longitudinal direction. The stay member 44a includes a flat first stay 46a that is disposed in contact with the base plate 42a, and a pair of second stays 47a, 48a that are connected to the first stay 46a and face each other with a gap in the width direction. In this embodiment, the linear motion mechanism 11a is disposed above the base plate 42a via the first stay 46a included in the stay member 44a.

[0031] The cover member 43a has a rectangular parallelepiped outer shape extending in the longitudinal direction. The cover member 43a is disposed above the base plate 42a. The cover member 43a covers the linear motion mechanism 11a. The cover member 43a includes a pair of side walls 51a, 52a located on the side surfaces of the linear motion mechanism, an upper wall 53a connected to the pair of side walls 51a, 52a and located above the linear motion mechanism 11a, a front wall 54a located at one end in the longitudinal direction, and a rear wall 55a located at the other end in the longitudinal direction. The pair of side walls 51a, 52a face each other in the width direction. The front wall 54a and the rear wall 55a face each other in the longitudinal direction.

[0032] A fastener 56a extending in the longitudinal direction is provided on the upper wall portion 53a of the cover member 43a. The fastener 56a includes a first element 61a extending in the longitudinal direction, a second element 62a extending in the longitudinal direction along the first element 61a, a first slider 63a, and a second slider 64a. The second element 62a is provided so as to be able to mesh with the first element 61a. The first slider 63a is attached to the first element 61a and the second element 62a. The second slider 64a is also attached to the first element 61a and the second element 62a. The second slider 64a is positioned spaced apart in the longitudinal direction from the first slider 63a. The first slider 63a and the second slider 64a move the first element 61a and the second element 62a away from each other as they move in the direction opposite to the side where the other is located, and also mesh the first element 61a and the second element 62a with each other as they move in the direction towards the side where the other is located.

[0033] The slide block 13a is attached to the first slider 63a and the second slider 64a. In this embodiment, the slide block 13a is fixed to the first slider 63a and the second slider 64a. The slide block 13a is disposed above the upper wall portion 53a of the cover member 43a. In other words, the slide block 13a is not covered by the cover member 43a and is exposed from the cover member 43a.

[0034] The fastener 56a extends to one longitudinal end of the cover member 43a. Specifically, the fastener 56a extends to the front wall portion 54a of the cover member 43a. However, the fastener 56a does not extend to the rear wall portion 55a of the cover member 43a.

[0035] Here, one end of the cover member 43a is configured to be openable and closable. In this embodiment, the front wall portion 54a located at one end of the cover member 43a is configured to be openable and closable. FIG. 7 is a schematic perspective view showing the front wall portion 54a in an open state. Note that FIG. 1 shows the front wall portion 54a in a closed state. Referring also to FIG. 7, the front wall portion 54a has a slit 65a extending in the height direction. The slit 65a is located at the center in the width direction. The front wall portion 54a is configured by bending a first end region 66a in the longitudinal direction of the top wall portion 53a and second end regions 67a, 68a in the longitudinal direction of each of the pair of side wall portions 51a, 52a. In this embodiment, the first end region 66a is divided into two parts by the slit 65a, and each part is connected to the top wall portion 53a.

[0036] Here, an example of how to remove the cover member 43a will be briefly described. First, the slide block 13a, which is a movable member, is moved together with the first slider 63a and the second slider 64a to the area where the front wall portion 54a is located. Then, the front wall portion 54a is opened as shown in FIG. 7. In this case, the first end region 66a and the second end regions 67a, 68a, which were previously bent, are released. Next, referring to FIG. 8, the cover member 43a is pulled out in the direction of arrow D (opposite to arrow X). FIG. 8 is a schematic perspective view showing the state in which the cover member 43a is being pulled out. In this case, the first slider 63a and the second slider 64a remain attached to the slide block 13a, and only the cover member 43a is pulled out. Note that a new cover member can be installed by reversing the removal procedure.

[0037] According to the linear motion unit 10a, when removing the cover member 43a from the linear motion unit 10a, such as when replacing the cover member 43a, the front wall portion 54a, which is one end of the cover member 43a, is opened and the cover member 43a is pulled toward the other end. Since the fastener 56a reaches one end of the cover member 43a, the cover member 43a can be pulled out as is. Therefore, the cover member 43a can be removed from the linear motion unit 10a without removing the slide block 13a to which the first slider 63a and the second slider 64a are fixed. As a result, when removing the cover member 43a, the steps of removing and reattaching the slide block 13a, which is a moving member, can be omitted. As described above, the linear motion unit 10a improves the workability when replacing the cover member 43a.

[0038] In this embodiment, the cover member 43a includes side walls 51a, 52a located on the lateral sides of the linear motion mechanism 11a, an upper wall 53a connected to the side walls 51a, 52a and provided with a fastener 56a and located above the linear motion mechanism 11a, a front wall 54a located at one longitudinal end, and a rear wall 55a located at the other longitudinal end. The front wall 54a is configured to be openable and closable. The side walls 51a, 52a, the upper wall 53a, the front wall 54a, and the rear wall 55a surround the linear motion mechanism 11a, and the cover member 43a can be pulled out from the rear wall 55a side. This allows the cover member 43a to more appropriately cover the linear motion mechanism 11a while improving operability and enhancing the dustproofness of the linear motion mechanism 11a.

[0039] In this embodiment, the front wall 54a is configured by bending a first longitudinal end region 66a of the upper wall 53a and second longitudinal end regions 67a, 68a of the side walls 51a, 52a. By configuring the front wall 54a in this manner, the openable / closable configuration described above can be easily realized, further improving workability.

[0040] In this embodiment, the housing 41a includes a base plate 42a. The cover member 43a is attached to the base plate 42a. The linear motion mechanism 11a is disposed in a space surrounded by the cover member 43a and the base plate 42a. Therefore, the base plate 42a and the cover member 43a can easily seal the linear motion mechanism 11a. This can improve dust resistance. Note that the housing 41a may not include the base plate 42a. In other words, this embodiment may also be applied to a case where the linear motion mechanism 11a is fixed directly to a mating member (mounting location) without using the base plate 42a, and the linear motion mechanism 11a is covered by the cover member 43a included in the housing 41a.

[0041] In this embodiment, rail 12a, which serves as a track member, is formed with first rolling surfaces 21a, 22a extending in the longitudinal direction. Second rolling surfaces 31a, 32a are formed on the moving member, facing first rolling surfaces 21a, 22a and forming rolling element rolling paths between first rolling surfaces 21a, 22a and second rolling surfaces 31a, 32a. Linear motion mechanism 11a includes balls 15a as rolling elements that circulate in a rolling element circulating path including the rolling element rolling path as the moving member moves linearly in the longitudinal direction of the track member. Such a linear motion mechanism utilizes the balls 15a to smoothly move the moving member.

[0042] In the above embodiment, the front wall is configured to be openable and closable. However, this is not limiting. At least one of the front wall and the rear wall may be configured to be openable and closable. In this manner, the linear motion mechanism is surrounded by the side wall, the upper wall, the front wall, and the rear wall, and the cover member can be pulled out from either the front wall or the rear wall. Therefore, the linear motion mechanism can be more appropriately covered by the cover member while improving workability, thereby enhancing the dustproofness of the linear motion mechanism.

[0043] (Embodiment 2) Another embodiment, embodiment 2, will now be described. Fig. 9 is a schematic perspective view showing a linear motion unit according to embodiment 2 of the present disclosure. Fig. 10 is a schematic side view showing a cover member included in the linear motion unit shown in Fig. 9. Fig. 11 is a schematic perspective view showing a state in which the cover member included in the linear motion unit shown in Fig. 9 has been removed. Fig. 12 is a schematic perspective view showing a state in which the cover member has been pulled out. The linear motion unit according to embodiment 2 basically has the same configuration as in embodiment 1 and achieves the same effects. However, the linear motion unit according to embodiment 2 differs from embodiment 1 mainly in that the linear motion mechanism is a ball screw.

[0044] 9, 10, 11, and 12, linear motion unit 10b according to the second embodiment includes housing 41b including cover member 43b and ball screw 11b as a linear motion mechanism. Ball screw 11b includes screw shaft 16b as a track member and nut 17b. Slide block 13b as a moving member is fixed to nut 17b. Rotation of screw shaft 16b allows nut 17b and slide block 13b fixed to nut 17b to move linearly along the X direction, which is the longitudinal direction of the screw shaft.

[0045] The cover member 43b is provided with a zipper 56b extending in the longitudinal direction. The zipper 56b reaches one end of the cover member 43b in the longitudinal direction. The one end of the cover member 43b is configured to be freely openable and closable.

[0046] With this configuration, the cover member 43b can be removed from the linear motion unit 10b without removing the slide block 13b. As a result, when removing the cover member 43b, the steps of removing the slide block 13b, which is a moving member, and then reattaching the slide block 13b can be omitted. As described above, with this linear motion unit 10b, the workability when replacing the cover member 43b can be improved.

[0047] In the above embodiment, the linear motion unit 10b includes a ball screw 11b as a linear motion mechanism, but this is not limited thereto. The linear motion mechanism may be a triangular screw, a trapezoidal screw, or a square screw, each of which is a sliding screw. That is, the linear motion mechanism included in the linear motion unit 10b may include a triangular screw, a trapezoidal screw, a square screw, or a ball screw. Such a linear motion mechanism can rotate a screw shaft using a motor or the like to move a moving mechanism, and can be effectively used in an actuator or the like.

[0048] (Embodiment 3) Another embodiment, embodiment 3, will now be described. Fig. 13 is a schematic perspective view showing a linear motion unit according to embodiment 3 of the present disclosure. Fig. 14 is a schematic perspective view showing a state in which the front wall portion is released. Fig. 15 is a schematic perspective view showing a state in which the cover member is being pulled out. The linear motion unit according to embodiment 3 basically has the same configuration as embodiment 1 and achieves the same effects. However, the linear motion unit according to embodiment 3 differs from embodiment 1 mainly in that it includes multiple fasteners.

[0049] 13, 14, and 15, the linear motion unit 10c according to the second embodiment includes a cover member 43c. The cover member 43c includes a plurality of fasteners 56c, 57c, specifically, two fasteners 56c, 57c. The fasteners 56c, 57c are provided in pairs spaced apart in a direction intersecting the longitudinal direction, which in this embodiment is the width direction perpendicular to the longitudinal direction. In this way, even when a plurality of fasteners 56c, 57c are used, the cover member 43c can be easily removed, improving workability.

[0050] The present invention is intended to cover a wide range of applications, including those related to the present invention, including those related to the present invention.

[0051] 10a, 10b, 10c Linear motion unit, 11a Linear motion mechanism, 11b Ball screw, 12a Rail, 13a, 13b Slide block, 15a Ball, 16b Screw shaft, 17b Nut, 21a, 22a First rolling surface, 23a Casing, 24a First end cap, 25a Second end cap, 26a Casing body, 27a First sleeve portion, 28a Second sleeve portion, 29a First return path, 31a, 32a Second rolling surface, 33a First rolling element rolling path, 34a Second rolling element rolling path, 35a Second return path, 41a, 41b Housing, 42a Base plate, 43a, 43b, 43c Cover member, 44a Stay member, 46a First stay, 47a, 48a Second stay, 51a, 52a Side wall portion 53a Upper wall portion 54a Front wall portion 55a Rear wall portion 56a, 56b, 56c, 57c Fastener 61a First element 62a Second element 63a First slider 64a Second slider 65a Slit 66a First end region 67a, 68a Second end region.

Claims

1. A device comprising: a linear motion mechanism; and a housing that houses the linear motion mechanism, wherein the linear motion mechanism comprises: a track member; and a moving member that is linearly movable along the longitudinal direction of the track member, wherein the housing comprises a cover member that covers the linear motion mechanism, wherein the cover member comprises a fastener extending in the longitudinal direction, wherein the fastener comprises: a first element extending in the longitudinal direction; a second element extending in the longitudinal direction along the first element and capable of engaging with the first element; a first slider attached to the first element and the second element; and a second slider attached to the first element and the second element and positioned away from the first slider in the longitudinal direction, wherein the first slider and the second slider move the first element and the second element away from each other as they move in a direction opposite to a side where the other element is located, and the first element and the second element engage with each other as they move in a direction towards a side where the other element is located, A linear motion unit, wherein the first slider and the second slider are fixable to the movable member, the fastener reaches at least one of the longitudinal ends of the cover member, and the one end of the cover member is configured to be freely opened and closed.

2. A linear motion unit as set forth in claim 1, wherein the fastener extends to both ends of the cover member in the longitudinal direction, and both ends of the cover member are configured to be freely opened and closed.

3. A linear motion unit as described in claim 1 or claim 2, wherein the cover member includes a side wall portion located on the side of the linear motion mechanism, an upper wall portion on which the fastener is provided and which is connected to the side wall portion and located above the linear motion mechanism, a front wall portion located at one end in the longitudinal direction, and a rear wall portion located at the other end in the longitudinal direction, and at least one of the front wall portion and the rear wall portion is configured to be freely opened and closed.

4. A linear motion unit as described in claim 3, wherein at least one of the front wall portion and the rear wall portion is formed by bending a first end region in the longitudinal direction of the upper wall portion and a second end region in the longitudinal direction of the side wall portion.

5. A linear motion unit as claimed in claim 1 or 2, wherein a plurality of said fasteners are provided at intervals in a direction intersecting said longitudinal direction.

6. A linear motion unit as described in claim 1 or claim 2, wherein the track member is formed with a first rolling surface extending in the longitudinal direction, the moving member is formed with a second rolling surface opposing the first rolling surface and forming a rolling body rolling path between the first rolling surface and the second rolling surface, and the linear motion mechanism further includes a plurality of rolling bodies that circulate in a rolling body circulation path including the rolling body rolling path as the moving member moves linearly in the longitudinal direction of the track member.

7. The linear motion unit according to claim 1 or 2, wherein the linear motion mechanism includes a triangular screw, a trapezoidal screw, a square screw or a ball screw.

8. A linear motion unit as described in claim 1 or claim 2, wherein the housing includes a base plate, the cover member is attached to the base plate, and the linear motion mechanism is disposed within a space surrounded by the cover member and the base plate.

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