Linear motion guide block

Abstract

The invention relates to a linear motion guide assembly comprising a rail, a slide, and several rollers. The slide comprises a slide body, whose first circulation path is arranged parallel to the load-bearing groove and includes a second rolling surface and a first guide surface which contacts the first end surface located on one side of the rollers to guide the rollers, an end cap, and a retaining element for holding the rollers in the slide body. Each roller circulates in a closed loop formed by the load-bearing groove, the first circulation path, and the second circulation path. The retaining element comprises a retaining plate extending along the longitudinal direction and having a second guide surface for guiding the rollers, and a mounting mechanism which attaches the retaining plate to the slide body. The second guide surface has several longitudinal recesses arranged to create clearances smaller than the diameter of the second end surface located on the other side of the rollers, and several contact points arranged between adjacent recesses and in contact with the second end surface.

Description

Linear motion guide unit

[0001] This disclosure relates to a linear motion guide unit. This application claims priority to Japanese Application No. 2023-181657, filed October 23, 2023, and incorporates by reference all of the contents of said Japanese application.

[0002] A linear guide unit is known that includes a rail, a roller as a rolling element, a slider that moves relative to the rail, and a retaining plate that holds the roller on the slider (see, for example, Patent Documents 1, 2, and 3).

[0003] JP 2016-164424 A JP 2023-102377 A JP 2009-236152 A

[0004] In a linear motion guide unit, if the sliding resistance of the slider is large, the smooth sliding of the slider is hindered, and it is therefore necessary to achieve smooth sliding of the slider.

[0005] Therefore, one of the objects is to provide a linear motion guide unit that can realize smooth sliding of the slider.

[0006] A linear motion guide unit according to the present disclosure includes a rail having a first raceway surface extending in the longitudinal direction, a slider attached to the rail for relative movement and having a second raceway surface opposing the first raceway surface, and a plurality of rollers serving as rolling elements that roll on a raceway formed by the first and second raceway surfaces. The slider includes a casing having a first circulation path parallel to the raceway and including a first guide surface and a second raceway surface that contact a first end face located on one side of the roller to guide the roller, an end cap located on one longitudinal side of the casing and having a second circulation path connecting the raceway and the first circulation path, and a retaining member that holds the roller in the casing. Each roller circulates on a circular path formed by the raceway, the first circulation path, and the second circulation path. The retaining member includes a retaining plate extending in the longitudinal direction and having a second guide surface that guides the roller, and an attachment mechanism that attaches the retaining plate to the casing. The second guide surface is provided with a plurality of recesses arranged at intervals smaller than the diameter of the second end face located on the other side of the roller in the longitudinal direction, and a plurality of contact portions arranged between adjacent recesses and in contact with the second end face.

[0007] According to the linear motion guide unit, smooth sliding of the slider can be achieved.

[0008] FIG. 1 is a schematic perspective view showing a linear motion guide unit in embodiment 1 of the present disclosure. FIG. 2 is a schematic cross-sectional view taken along the cross section indicated by arrows II-II in FIG. 1. FIG. 3 is a schematic perspective view of a retaining plate. FIG. 4 is an enlarged view of an area indicated by IV in FIG. 3. FIG. 5 is a schematic side view of the retaining plate. FIG. 6 is a schematic cross-sectional view showing a portion of a slider when a retaining band is attached. FIG. 7 is a schematic cross-sectional view showing an enlarged portion of a roller and slider with a retaining plate attached.

[0009] [Summary of the Embodiment] The linear motion guide unit of the present disclosure includes a rail having a first raceway surface extending in the longitudinal direction, a slider attached to the rail for relative movement and having a second raceway surface opposing the first raceway surface, and rollers as rolling elements that roll on a raceway formed by the first raceway surface and the second raceway surface. The slider includes a casing having a first circulation path parallel to the raceway path and including a first guide surface and a second raceway surface that contact a first end face located on one side of the roller to guide the roller, an end cap located on one longitudinal side of the casing and having a second circulation path connecting the raceway and the first circulation path, and a retaining member that holds the roller in the casing. Each roller circulates on a circular path formed by the raceway, the first circulation path, and the second circulation path. The retaining member includes a retaining plate extending in the longitudinal direction and having a second guide surface that guides the roller, and an attachment mechanism that attaches the retaining plate to the casing. The second guide surface is provided with a plurality of recesses arranged at intervals smaller than the diameter of the second end face located on the other side of the roller in the longitudinal direction, and a plurality of contact portions arranged between adjacent recesses and in contact with the second end face.

[0010] According to the linear guide unit of the present disclosure, the second guide surface included in the retaining plate and guiding the roller includes multiple recesses and multiple contact portions arranged alternately in the longitudinal direction. The multiple contact portions included in the second guide surface contact the second end face of the roller, thereby guiding the roller in the load region. In this case, the recesses included in the second guide surface do not contact the second end face of the roller, thereby reducing the contact area of ​​the second guide surface with the second end face of the roller. This reduces frictional resistance between the second end face of the roller and the second guide surface. In this case, the multiple contact portions are arranged between adjacent recesses at intervals smaller than the diameter of the second end face of the roller, so the second end face of the roller and the contact portions can always maintain contact, thereby reliably guiding the roller. This reduces sliding resistance and achieves smooth sliding of the slider.

[0011] In the linear guide unit described above, the contact portion may contact the second end face in a region including the central axis of rotation of the roller when viewed in the longitudinal direction. The slider may have a space between the second end face and the retaining plate in a region on the outer peripheral surface side of the contact portion. This reduces frictional resistance between the second guide surface and the second end face when viewed in the longitudinal direction, while reducing the risk of the second end face of the roller being pressed against the second end face by tilting in the direction of the central axis of rotation of the roller, thereby enabling balanced guidance of the roller. This therefore makes it possible to more stabilize the posture of the roller.

[0012] In the linear motion guide unit, the first contact width of the contact portion may be 20% to 30% of the diameter of the second end face when viewed in the longitudinal direction. By doing so, the contact area between the second end face and the contact portion when viewed in the longitudinal direction can be made appropriate, thereby reducing sliding resistance and stress concentration.

[0013] In the linear motion guide unit, the second contact width of the contact portion in the longitudinal direction may be 55% to 75% of the diameter of the second end face. By doing so, the contact area between the second end face and the contact portion in the longitudinal direction can be made appropriate, thereby reducing sliding resistance and stress concentration.

[0014] In the linear guide unit, the mounting mechanism may include an elastically deformable retaining band. The retaining plate may have a slit formed therethrough at the longitudinal end. The slit may be formed at a position where the retaining band contacts and presses the retaining plate. This allows the retaining plate to be elastically deformed appropriately in the area of ​​the retaining plate where the slit is formed, and the roller's posture can be corrected while more appropriately pressing the second end surface of the roller, allowing it to move to the load area. This allows for smoother sliding of the slider.

[0015] In the linear guide unit, a pair of slits may be provided at both longitudinal end portions, thereby realizing a reduction in sliding resistance during linear reciprocating motion of the slider.

[0016] In the linear motion guide unit, the longitudinal length of the slit may be such that the amount of elastic deformation of the retaining plate is 20% to 40% of the maximum gap in the direction of the central axis of rotation of the roller. By doing so, it is possible to suppress tilt of the roller after it enters the load area while allowing the retaining plate to be elastically deformed appropriately.

[0017] The linear motion guide unit disclosed herein includes a rail having a first raceway surface extending in the longitudinal direction, a slider attached to the rail for relative movement and having a second raceway surface opposing the first raceway surface, and a plurality of rollers serving as rolling elements that roll on a raceway formed by the first and second raceway surfaces. The slider includes a casing having a first circulation path parallel to the raceway and including a first guide surface and a second raceway surface that contact a first end face located on one side of the roller to guide the roller, an end cap located on one longitudinal side of the casing and having a second circulation path connecting the raceway and the first circulation path, and a retaining member that holds the roller in the casing. Each roller circulates on a circular path formed by the raceway, the first circulation path, and the second circulation path. The retaining member includes a retaining plate extending in the longitudinal direction and having a second guide surface that guides the roller, and an attachment mechanism that attaches the retaining plate to the casing. The second guide surface is provided with a plurality of recesses arranged at intervals smaller than the diameter of the second end face located on the other side of the roller in the longitudinal direction, and a plurality of contact portions arranged between adjacent recesses and in contact with the second end face. As viewed in the longitudinal direction, the contact portions contact the second end face in an area including the central axis of rotation of the roller. A space is provided in the slider between the second end face and the retaining plate in an area on the outer circumferential surface side of the contact portions.

[0018] According to such a linear motion guide unit, the position of the roller can be made more stable, and smooth sliding of the slider can be realized.

[0019] [Specific Example of Embodiment] Next, an example of a specific embodiment of the linear motion guide 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.

[0020] (Embodiment 1) First, embodiment 1, which is an embodiment of the present disclosure, will be described. FIG. 1 is a schematic perspective view showing a linear guide unit in embodiment 1 of the present disclosure. FIG. 2 is a schematic cross-sectional view taken along the cross section indicated by arrows II-II in FIG. 1. In FIG. 1 and the following figures, the X direction indicates the short side direction, which is the width direction of the linear guide unit, the Y direction indicates the longitudinal direction of the linear guide unit, and the Z direction indicates the thickness direction (height direction) of the linear guide unit. The X direction, Y direction, and Z direction are all orthogonal to each other. FIG. 2 is a cross-sectional view taken along a plane perpendicular to the Y direction, i.e., the X-Z plane.

[0021] 1 and 2 , a linear guide unit 10a according to a first embodiment of the present disclosure includes a rail 11a serving as a track rail, a slider 21a, and multiple rollers 20a, 20b, 20c, and 20d serving as rolling elements. The rail 11a extends straight in the Y direction, which is the longitudinal direction. By including multiple rollers 20a, 20b, 20c, and 20d serving as rolling elements, the linear guide unit 10a according to the first embodiment can achieve a larger load rating while remaining compact in size compared to, for example, a system in which the rolling elements are balls. In this embodiment, the linear guide unit 10a is a so-called four-row linear guide unit. The rollers 20a and 20b each include rolling surfaces 28a and 28b, first end faces 51a and 51b located on one side of the rollers 20a and 20b in the direction of the central rotation axis, and second end faces 52a and 52b located on the other side of the central rotation axis. Similarly, rollers 20c and 20d each include a rolling surface, a first end face located on one side of rollers 20c and 20d in the direction of the central axis of rotation, and a second end face located on the other side of rollers 20c and 20d in the direction of the central axis of rotation.

[0022] First, the configuration of the rail 11a will be described. The rail 11a includes a rail upper end surface 12a and a rail lower end surface 12b spaced apart in the Z direction, a first rail side surface 13a and a second rail side surface 13b spaced apart in the X direction, and a rail front end surface 14a and a rail rear end surface 14b spaced apart in the Y direction. That is, the rail 11a includes the first rail side surface 13a and the second rail side surface 13b extending parallel to each other along the longitudinal direction. The rail 11a has a pair of first raceway grooves 15a, 15b extending parallel to each other along the longitudinal direction. The first raceway groove 15a is provided in the first rail side surface 13a. The first raceway groove 15b is provided in the second rail side surface 13b.

[0023] The first raceway groove 15a is composed of first raceway surfaces 16a and 16b and a sidewall surface 17a. The first raceway surface 16a is inclined with respect to the X-Y plane and is provided on the rail upper end surface 12a side. The first raceway surface 16b is inclined with respect to the X-Y plane and is provided on the rail lower end surface 12b side. The sidewall surface 17a is provided continuous with each of the first raceway surfaces 16a and 16b. Like the first raceway groove 15a, the first raceway groove 15b is also composed of first raceway surfaces 16c and 16d and a sidewall surface 17b. The first raceway surface 16c is inclined with respect to the X-Y plane and is provided on the rail upper end surface 12a side. The first raceway surface 16d is inclined with respect to the X-Y plane and is provided on the rail lower end surface 12b side. The side wall surface 17b is provided so as to be continuous with the first raceway surface 16c and the first raceway surface 16d. That is, the rail 11a includes the first raceway surfaces 16a, 16b, 16c, and 16d extending in the longitudinal direction. The linear motion guide unit 10a including such a rail 11a is suitable for use in machine tools, assembly equipment, conveying machines, etc.

[0024] The rail 11a is provided with a plurality of through holes 18 that penetrate in the Z direction from the rail upper end surface 12a to the rail lower end surface 12b. The plurality of through holes 18 are provided at intervals in the Y direction. For example, when using the linear motion guide unit 10a, the through holes 18 are each effectively used when attaching the rail 11a to a predetermined location.

[0025] Next, the configuration of the slider 21a will be described. The slider 21a is attached to the rail 11a so as to be relatively movable. In this embodiment, the slider 21a is slidably mounted across the rail 11a. The slider 21a is provided with a fitting portion 24a that is recessed in the Z direction, and the slider 21a is attached so that the rail 11a is fitted into this fitting portion 24a. In other words, the slider 21a is attached so as to straddle the rail 11a and is configured to be movable in the Y direction.

[0026] The slider 21a includes a casing 22a, a pair of end caps 23a, 23b, specifically a first end cap 23a and a second end cap 23b, and retaining members 41a, 41b that retain the rollers 20a, 20b, 20c, and 20d on the casing 22a. The configuration of the retaining members 41a, 41b will be described in detail later. The first end cap 23a is disposed on one longitudinal side of the casing 22a, specifically, on the rail front end surface 14a side of the casing 22a in the longitudinal direction. The second end cap 23b is disposed on the other longitudinal side of the casing 22a, specifically, on the rail rear end surface 14b side of the casing 22a in the longitudinal direction. That is, the slider 21a includes a pair of end caps 23a, 23b disposed on both longitudinal sides of the casing 22a. The first end cap 23a has a through-hole that penetrates in the Y direction. Both the first end cap 23a and the second end cap 23b are so-called plate-shaped, with their thickness direction aligned along the longitudinal direction. The first end cap 23a is connected to the casing 22a with multiple bolts via the through-hole. The second end cap 23b is connected to the casing 22a with multiple bolts via the through-hole. The end cap 23a also has a supply hole (not shown) for supplying lubricating oil. The same applies to the end cap 23b.

[0027] The slider 21a includes an end seal 27a disposed on one longitudinal side of the first end cap 23a and a lubricating member (not shown) that applies lubricating oil. The end seal 27a and the lubricating member are attached to the first end cap 23a with bolts. Similar to the first end cap 23a, the second end cap 23b, along with the end seal 27b and the lubricating member, is connected to the casing 22a with multiple bolts. The casing 22a is provided with multiple through holes 29 that penetrate in the Z direction. In this embodiment, six through holes 29 are provided. The six through holes 29 are spaced apart in the X and Y directions and are used, for example, to connect the slider 21a to another member.

[0028] The casing 22a includes second raceway surfaces 32a, 32b, 32c, and 32d that face the first raceway surfaces 16a, 16b, 16c, and 16d, respectively. The raceway 31a on which the roller 20a rolls is composed of the first raceway surface 16a and the second raceway surface 32a. The raceway 31b on which the roller 20b rolls is composed of the first raceway surface 16b and the second raceway surface 32b. The raceway 31c on which the roller 20c rolls is composed of the first raceway surface 16c and the second raceway surface 32d. The raceway 31d on which the roller 20d rolls is composed of the first raceway surface 16d and the second raceway surface 32d.

[0029] The casing 22a is provided with first circulation paths 33a, 33b, 33c, and 33d that run parallel to the raceways 31a, 31b, 31c, and 31d, respectively. The first circulation paths 33a, 33b, 33c, and 33d are also referred to as return paths. A hollow cylindrical sleeve 34a formed by combining a first divided member 35a and a second divided member 36a is disposed within the first circulation path 33a. A plurality of rollers 20a move within the sleeve 34a. Similarly, a hollow cylindrical sleeve 34b formed by combining a first divided member 35b and a second divided member 36b is disposed within the first circulation path 33b. A hollow cylindrical sleeve 34c formed by combining a first divided member 35c and a second divided member 36c is disposed within the first circulation path 33c. A hollow cylindrical sleeve 34d formed by combining a first divided member 35d and a second divided member 36d is disposed within the first circulation path 33d.

[0030] The casing 22a includes first guide surfaces 39a, 39b, 39c, and 39d that contact first end surfaces 51a and 51b located on one side of the rollers 20a, 20b, 20c, and 20d to guide the rollers 20a, 20b, 20c, and 20d.

[0031] The first end cap 23a is provided with a second circulation path (not shown). The second circulation path is also called a direction change path. The second circulation path has an arc-shaped recess in the thickness direction (Y direction) of the first end cap 23a so as to allow movement of the plurality of rollers 20a. The second circulation path connects the raceway path 31a and the first circulation path 33a. The first end cap 23a also includes a second circulation path connecting the raceway path 31b and the first circulation path 33b, a second circulation path connecting the raceway path 31c and the first circulation path 33c, and a second circulation path connecting the raceway path 31d and the first circulation path 33d. Similarly to the first end cap 23a, the second end cap 23b includes a second circulation path connecting the raceway 31a and the first circulation path 33a, a second circulation path connecting the raceway 31b and the first circulation path 33b, a second circulation path connecting the raceway 31c and the first circulation path 33c, and a second circulation path connecting the raceway 31d and the first circulation path 33d. The rollers 20a circulate in a circular path formed by the raceway 31a, the second circulation path of the second end cap 23b, the first circulation path 33a, and the second circulation path of the first end cap 23a. The rollers 20b circulate in a circular path formed by the raceway 31b, the second circulation path of the second end cap 23b, the first circulation path 33b, and the second circulation path of the first end cap 23a. The rollers 20c circulate in a circular path formed by the raceway 31c, the second circulation path of the second end cap 23b, the first circulation path 33c, and the second circulation path of the first end cap 23a. The rollers 20d circulate in a circular path formed by the raceway 31d, the second circulation path of the second end cap 23b, the first circulation path 33d, and the second circulation path of the first end cap 23a.

[0032] Next, the configuration of the holding members 41a and 41b that hold the rollers 20a, 20b, 20c, and 20d in the casing 22a will be described. The holding member 41a includes a holding plate 42a and a holding band 43a as an attachment mechanism. Similarly to the holding member 41a, the holding member 41b includes a holding plate 42b and a holding band 43b. The configuration of the holding member 41b is similar to that of the holding member 41a, and therefore its description will be omitted.

[0033] FIG. 3 is a schematic perspective view of the retaining plate 42a. FIG. 4 is an enlarged view of the area indicated by IV in FIG. 3. FIG. 5 is a schematic side view of the retaining plate 42a. FIG. 5 is a view viewed in the opposite direction to the direction indicated by arrow X. FIG. 6 is a schematic cross-sectional view showing a portion of the slider 21a when the retaining band 43a is attached. FIG. 6 is a cross-sectional view taken along a plane parallel to the X-Y plane. In FIG. 6, the state before the retaining band 43a is attached is shown by a two-dot chain line. FIG. 7 is a schematic cross-sectional view showing an enlarged portion of the roller 20a and slider 21a when the retaining plate 42a is attached.

[0034] 3 to 7, the holding plate 42a and the holding band 43a included in the holding member 41a each have a shape that extends in the longitudinal direction. The holding plate 42a has a groove 47a that is recessed to accommodate the holding band 43a. Specifically, the rod-shaped portion 44a of the holding band 43a is fitted into the groove 47a. The groove 47a has a shape that extends along the longitudinal direction. Similar to the holding plate 42a, the holding plate 42b also has a groove 47b.

[0035] Briefly, the configuration of the retaining band 43a will be described. The retaining band 43a is formed by bending, for example, a thin, elongated metal member. The retaining band 43a is capable of a certain degree of elastic deformation. The retaining band 43a includes a rod-shaped portion 44a extending in the longitudinal direction and a pair of claw portions 45a, 45b disposed at both longitudinal ends of the rod-shaped portion 44a. Before the retaining band 43a is attached, the rod-shaped portion 44a is shaped so that both longitudinal ends are bent in the direction of arrow X when the longitudinal center of the rod-shaped portion 44a contacts the retaining plate 42a. The pair of claw portions 45a, 45b are each bent in the X direction, and the tip portions 48a, 48b of the pair of claw portions 45a, 45b are further bent in the Y direction. To attach the retaining band 43a, the rod-shaped portion 44a is fitted into the groove 47a, the center of the rod-shaped portion 44a is pressed against the retaining plate 42a, and the pair of claws 45a, 45b and the pair of tip portions 48a, 48b are hooked onto the pair of end caps 23a, 23b while holding the retaining plate 42a. This causes slight elastic deformation at both ends of the rod-shaped portion 44a, and this pressing force attaches the retaining plate 42a to the casing 22a. The areas indicated by 49a, 49b, 49c, and 49d in Figure 6 are areas where loads are concentrated.

[0036] Next, the configuration of the holding plate 42a will be described. The holding plate 42a includes second guide surfaces 46a, 46b that contact second end surfaces 52a, 52b located on the other side of the rollers 20a, 20b, respectively, to guide the rollers 20a, 20b. Referring particularly to FIG. 4, the second guide surface 46a is provided with a plurality of recesses 53a and a plurality of contact portions 54a. The same is true for the second guide surface 46b. The plurality of recesses 53a are arranged in a longitudinal direction that is equal to or larger than the diameter D of the second end surface 52a of the roller 20a. １ The distance D is smaller than ２ The recesses 53a are arranged with a gap between them. Each of the recesses 53a is configured to extend in a groove-like manner in a direction perpendicular to the rotational axis of the roller 20a on the second guide surface 46a. The contact portions 54a come into contact with the second end surface 52a of the roller 20a. The contact portions 54a are arranged between adjacent recesses 53a. In other words, the recesses 53a and the contact portions 54a are arranged alternately in the longitudinal direction on the second guide surface 46a.

[0037] 7, the contact portion 54a contacts the second end surface 52a in a region including the rotation axis 25a of the roller 20a when viewed in the longitudinal direction. The slider 21a has spaces 55a, 55b between the second end surface 52a and the retaining plate 42a in a region on the outer circumferential surface side of the contact portion 54a. In FIG. 7, the rotation axis 25a is indicated by a dashed line. Also, when viewed in the longitudinal direction, the first contact width L of the contact portion 54a １ is the diameter D of the second end surface 52a １ In this embodiment, it is 25%. Also, referring to FIG. 4, the second contact width L of the contact portion 54a in the longitudinal direction is ２ is the diameter D of the second end surface 52a １ The ratio is 55% to 75% of the total area of ​​the second guide surface 46a. In this embodiment, it is 66%. That is, the second end surface 52a of the roller 20a moves in the longitudinal direction and comes into contact with the second guide surface 46a in a region where the contact portion 54a, which is not provided with the recess 53a and the spaces 55a and 55b, is located.

[0038] The retaining plate 42a has slits 56a and 56b. The slits 56a and 56b are provided as a pair at both longitudinal end sides. The slits 56a and 56b penetrate the retaining plate 42a at the longitudinal end sides. In this embodiment, the slits 56a and 56b are provided within the groove portion 47a. The slits 56a and 56b are provided at positions where the retaining band 43a contacts and presses the retaining plate 42a. Specifically, the slits 56a and 56b are provided at positions in the longitudinal direction that include the regions 49a and 49b.

[0039] In this embodiment, the longitudinal length of the slit 56a is set so that the amount of elastic deformation of the holding plate 42a is 20% to 40% of the maximum gap in the direction of the rotation center axis 25a of the roller 20a. This will be explained as follows. With particular reference to Figures 6 and 7, the longitudinal length of the slit 56a is set to L ３ , the length of the roller 20a in the direction of the rotation center axis 25a is L ４, the distance between the holding plate 42a and the casing 22a in the direction of the rotation center axis 25a of the roller 20a is D ３ , the gap in the direction of the rotational center axis 25a of the roller 20a in the raceway 31a is defined as C. In this case, the gap C is the distance D ３ From length L ４ Here, the maximum clearance indicates the maximum length dimension in the design value (the tolerance in the direction of the rotation center axis 25a of the roller 20a). ３ is the length at which the amount of elastic deformation of the holding plate 42a is 20% to 40% of the maximum value of the gap C. The same applies to the slit 56b. Specific dimensions include, for example, the length L ３ is 10 mm, the gap C is 93 μm, and the elastic deformation amount of the holding plate 42 a is 30 μm.

[0040] In the linear guide unit 10a configured as described above, the second guide surface 46a, which is included in the retaining plate 42a and guides the roller 20a, includes a plurality of recesses 53a and a plurality of contact portions 54a arranged alternately in the longitudinal direction. The plurality of contact portions 54a included in the second guide surface 46a contact the second end surface 52a of the roller 20a, thereby guiding the roller 20a in the load region. In this case, the recesses 53a included in the second guide surface 46a do not contact the second end surface 52a of the roller 20a, thereby reducing the contact area of ​​the second guide surface 46a with the second end surface 52a of the roller 20a. This reduces the frictional resistance between the second end surface 52a of the roller 20a and the second guide surface 46a. In this case, the contact portions 54a are arranged between adjacent recesses 53a at intervals smaller than the diameter of the second end surface 52a of the roller 20a, so that the second end surface 52a of the roller 20a and the contact portions 54a can be maintained in constant contact with each other, thereby reliably guiding the roller 20a. This reduces sliding resistance and allows the slider 21a to slide smoothly.

[0041] In this embodiment, when viewed in the longitudinal direction, the contact portion 54a contacts the second end face 52a in a region including the central axis of rotation 25a of the roller 20a. The slider 21a has spaces 55a, 55b between the second end face 52a and the retaining plate 42a in a region on the outer circumferential surface side of the contact portion 54a. This reduces frictional resistance between the second guide surface 46a and the second end face 52a when viewed in the longitudinal direction, while reducing the risk of the roller 20a being tilted in the direction of the central axis of rotation and pressing against the second end face 52a of the roller 20a, thereby guiding the roller 20a in a balanced manner. This further stabilizes the posture of the roller 20a.

[0042] In this embodiment, the first contact width L of the contact portion 54a when viewed in the longitudinal direction is １ is the diameter D of the second end surface 52a １ Therefore, when viewed in the longitudinal direction, the contact area between the second end surface 52a and the contact portion 54a can be made appropriate, thereby reducing sliding resistance and stress concentration.

[0043] In this embodiment, the second contact width L of the contact portion 54a in the longitudinal direction ２ is the diameter D of the second end surface 52a １ Therefore, the contact area between the second end surface 52a and the contact portion 54a in the longitudinal direction can be made appropriate, thereby reducing sliding resistance and stress concentration.

[0044] In this embodiment, the attachment mechanism includes an elastically deformable retaining band 43a. The retaining plate 42a has slits 56a and 56b formed at its longitudinal ends. The slits 56a and 56b are located in the regions 49a and 49b where the retaining band 43a contacts and presses the retaining plate 42a. This allows the retaining plate 42a to be elastically deformed appropriately in the regions 49a and 49b of the retaining plate 42a where the slits 56a and 56b are formed. This allows the roller 20a to be more appropriately pushed against the second end surface 52a of the roller 20a, correcting its posture and moving it to the load region. This allows for smoother sliding of the slider 21a.

[0045] In this embodiment, a pair of slits 56a, 56b are provided at both longitudinal end sides, thereby reducing the sliding resistance during linear reciprocating motion of the slider 21a.

[0046] In this embodiment, the longitudinal lengths of the slits 56a and 56b are such that the amount of elastic deformation of the retaining plate 42a is 20% to 40% of the maximum gap in the direction of the rotational axis 25a of the roller 20a. Therefore, the retaining plate 42a is elastically deformed appropriately, while preventing the roller 20a from tilting after entering the load region.

[0047] While the above embodiment has been described with reference to a case where a slit is provided in the holding plate, the present invention is not limited to this. The holding plate may have no slit. Also, instead of providing a pair of slits, only one slit may be provided.

[0048] Furthermore, in the above embodiment, the mounting mechanism employs a configuration in which the holding plate is held on the casing side using a holding band, but this is not limited to this, and for example, the holding plate may be fixed to the casing side using a bolt or the like, or the holding plate may be glued to the casing side.

[0049] 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.

[0050] 10a Linear motion guide unit, 11a Rail, 12a Rail upper end surface, 12b Rail lower end surface, 13a First rail side surface, 13b Second rail side surface, 14a Rail front end surface, 14b Rail rear end surface, 15a, 15b First raceway groove, 16a, 16b, 16c, 16d First raceway surface, 17a, 17b Side wall surface, 18 Through hole, 20a, 20b, 20c, 20d Roller, 21a Slider, 22a Casing, 23a End cap (first end cap), 23b End cap (second end cap), 24a Fitting portion, 25a Rotation center shaft, 27a, 27b End seal, 28a, 28b Rolling surface, 31a, 31b, 31c, 31d Raceway, 32a, 32b, 32c, 32d Second raceway, 33a, 33b, 33c, 33d First circulation path, 34a, 34b, 34c, 34d Sleeve, 35a, 35b, 35c, 35d First divided member, 36a, 36b, 36c, 36d Second divided member, 37a Second circulation path, 39a, 39b, 39c, 39d First guide surface, 41a, 41b Holding member, 42a, 42b Holding plate, 43a, 43b Holding band, 44a Rod-shaped portion, 45a, 45b Claw portion, 46a, 46b Second guide surface, 47a, 47b Groove portion, 48a, 48b Tip portion, 51a, 51b First end surface, 52a, 52b Second end surface, 53a Recess, 54a: contact portion, 55a, 55b: spaces, 56a, 56b: slits.

Claims

1. A roller bearing comprising: a rail having a first raceway surface extending in a longitudinal direction; a slider attached to the rail so as to be movable relative to the rail and having a second raceway surface facing the first raceway surface; and rollers as a plurality of rolling bodies rolling on a raceway path formed by the first raceway surface and the second raceway surface, wherein the slider comprises: a casing having a first circulation path parallel to the raceway path, the casing including a first guide surface and the second raceway surface that contact a first end face located on one side of the roller to guide the roller; an end cap disposed on one side of the casing in the longitudinal direction and having a second circulation path connecting the raceway path and the first circulation path; and a retaining member that retains the roller in the casing, wherein each of the rollers circulates on a circular path formed by the raceway, the first circulation path and the second circulation path, and the retaining member comprises: a retaining plate extending in the longitudinal direction and having a second guide surface that guides the roller; and an attachment mechanism that attaches the retaining plate to the casing side, the second guide surface is provided with a plurality of recesses arranged at intervals smaller than a diameter of a second end face located on the other side of the roller in the longitudinal direction, and a plurality of contact portions arranged between adjacent recesses and in contact with the second end face.

2. A linear motion guide unit as described in claim 1, wherein, when viewed in the longitudinal direction, the contact portion contacts the second end face in a region including the central axis of rotation of the roller, and the slider has a space between the second end face and the retaining plate in a region on the outer circumferential surface side of the contact portion.

3. A linear motion guide unit as set forth in claim 1 or 2, wherein the first contact width of the contact portion, as viewed in the longitudinal direction, is 20% to 30% of the diameter of the second end face.

4. A linear motion guide unit as set forth in claim 1 or 2, wherein the second contact width of said contact portion in said longitudinal direction is 55% or more and 75% or less of the diameter of said second end face.

5. A linear motion guide unit as claimed in claim 1 or claim 2, wherein the mounting mechanism includes a retaining band capable of elastic deformation, the retaining plate is provided with a slit penetrating therethrough at the end side in the longitudinal direction, and the position at which the retaining band comes into contact with and presses against the retaining plate.

6. A linear motion guide unit as set forth in claim 5, wherein said slits are provided in pairs at both ends in the longitudinal direction.

7. A linear motion guide unit as described in claim 5, wherein the longitudinal length of the slit is such that the amount of elastic deformation of the retaining plate is 20% or more and 40% or less of the maximum gap in the direction of the central axis of rotation of the roller.

8. A roller bearing comprising: a rail having a first raceway surface extending in a longitudinal direction; a slider attached to the rail so as to be movable relative to the rail and having a second raceway surface facing the first raceway surface; and rollers as a plurality of rolling bodies rolling on a raceway path formed by the first raceway surface and the second raceway surface, wherein the slider comprises: a casing having a first circulation path parallel to the raceway path, the casing including a first guide surface and the second raceway surface that contact a first end face located on one side of the roller to guide the roller; an end cap arranged on one side of the casing in the longitudinal direction and having a second circulation path connecting the raceway path and the first circulation path; and a retaining member that retains the roller in the casing, wherein each of the rollers circulates on a circular path formed by the raceway, the first circulation path and the second circulation path, and the retaining member comprises: a retaining plate having a shape extending in the longitudinal direction and having a second guide surface that guides the roller; and an attachment mechanism that attaches the retaining plate to the casing side, the second guide surface is provided with a plurality of recesses arranged at intervals smaller than a diameter of a second end face located on the other side of the roller in the longitudinal direction, and a plurality of contact portions arranged between adjacent recesses and in contact with the second end face, wherein, as viewed in the longitudinal direction, the contact portions contact the second end face in a region including the central axis of rotation of the roller, and the slider is provided with a space between the second end face and the retaining plate in a region on the outer circumferential surface side of the contact portions.

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