JP2008175263A - Linear motion guide device - Google Patents

Abstract

A linear motion guide device capable of preventing or alleviating distortion of an infinite circulation path even when a member constituting a rolling element return passage extends in the longitudinal direction.
A linear guide (linear motion guide device) 10 includes a guide rail 12 and a slider 16 straddling the guide rail 12 so as to be relatively movable. The slider 16 includes a slider body 17 having a rolling element return passage 20 and a pair of end caps 22 attached to both ends of the slider body 17. The rolling element return passage 20 includes a through hole 32 formed in the slider body 17 and a circulation tube 30 that is a return guide member fitted into the through hole 32. Between the tube 30 and the end cap 22, a margin Y allowing the longitudinal extension of the circulation tube 30 is provided.
[Selection] Figure 2

Description

  The present invention relates to a linear motion guide device that is used in various machines such as a manufacturing apparatus, a processing machine, and a measuring instrument and has an infinite circulation path on which a plurality of rolling elements roll.

As this type of linear motion guide device, for example, techniques disclosed in Patent Documents 1 to 4 are disclosed.
In the technique described in Patent Document 1, the linear motion guide device (linear guide device) is provided so as to be able to move relative to the guide rail (rail) via a rolling element (ball) with respect to the guide rail. And a slider (moving base). This slider includes a slider body (main body) having a rolling element return passage (return passage) for constituting an infinite circulation path, and a pair of end caps attached to both ends of the slider body. Here, the rolling element return passage has a through hole formed in the slider body and a return guide member (pipe) press-fitted into the through hole. Then, both ends of the return guide member are fixed in contact with the end surfaces of the end caps constituting the direction changing path.

According to the technique described in Patent Document 1, the rolling element return passage for constituting the infinite circulation path is constituted by a through hole and a return guide member press-fitted into the through hole. Can be machined into a large diameter, thereby improving the machining efficiency.
Further, for example, in the technique described in Patent Document 2, in addition to the same configuration as the technique described in Patent Document 1, the rolling elements are arranged in the endless circulation path so as to be rotatable at a predetermined interval. The structure provided with a rolling element accommodation belt (ball chain) is disclosed. Here, the rolling element housing belt has flanges on both sides thereof, and on the other hand, the return guide member constituting the rolling element return passage is formed with a concave guide groove along the rolling direction of the rolling element. Yes. And the rolling element accommodation belt is hold | maintained by the guide groove on the both sides. Thus, the rolling elements held and arranged on the rolling element accommodation belt can smoothly circulate in the endless circulation path without meandering.

Further, for example, in the technology described in Patent Document 3, in addition to the same configuration as the technology described in Patent Document 1, the circulation path constituting portion constituting the infinite circulation path is resin-molded separately from the slider body. The slider is incorporated into the slider body while ensuring as much as possible the continuity of the connecting portions of the circulation path components. This facilitates molding and manufacturing.
For example, in the technique described in Patent Document 4, in addition to the structure similar to the technique described in Patent Document 1, the return guide member is formed of a pipe divided into a plurality of parts in the longitudinal direction to form a rolling element return passage. ing. This is intended to reduce costs and improve productivity.
Japanese Patent Laid-Open No. 61-136805 (FIG. 1) Japanese Patent Laid-Open No. 11-315833 (FIG. 5) Japanese Patent No. 3571911 (FIG. 1) Japanese Patent Laying-Open No. 2005-042776 (FIG. 1)

By the way, when this type of linear motion guide device is used at a high temperature, or when used at a high speed / high acceleration / deceleration, the inside of the slider becomes hot due to the circulation resistance of the rolling elements.
However, in the technique described in Patent Document 1, when used under such conditions, the pipe-shaped return guide member is inevitably stretched due to temperature changes. Such elongation occurs even when a metal or ceramic is used as the material of the return guide member, but is particularly remarkable when a synthetic resin (plastic) is used.

  Since both ends of the return guide member are fixed in contact with the end surfaces of the end caps constituting the direction change path, when the return guide member is extended as described above, the end caps are pushed outward. In addition, the return guide member is compressed in the longitudinal direction. Therefore, the direction changing path is deformed or the return guide member that constitutes the rolling element return path is bent by the mutually pressing forces. As a result, the infinite circulation path is distorted, and the smooth circulation of the rolling elements may be hindered.

  In this type of linear motion guide device, a lubricant such as oil or grease is usually enclosed in an infinite circuit for lubrication. Therefore, if it is a return guide member made of synthetic resin, it swells due to the oil contained in these lubricants. In particular, since the return guide member is usually relatively long, the size of the return guide member is significantly increased due to swelling in the longitudinal direction. As a result, the increase in size due to such swelling also causes distortion in the infinite circuit.

And such a problem is the same also in the technique of the said patent documents 2-4, and the dimensional change in the longitudinal direction of the return guide member which comprises a rolling-element return path generate | occur | produces. And if such a change in dimension occurs in the return guide member and the return guide member bends, deformation of the infinite circuit is inevitable in any of the techniques described in any of the above-mentioned patent documents.
Therefore, the present invention has been made paying attention to such problems, and even when the members constituting the rolling element return passage extend in the longitudinal direction, the distortion of the infinite circuit is prevented or An object of the present invention is to provide a linear motion guide device that can be relaxed.

  In order to solve the above-mentioned problems, a first invention of the present invention is a guide rail having a rolling element guide surface, and is disposed so as to be relatively movable with respect to the guide rail and faces the rolling element guide surface. A slider having a load rolling element guide surface that forms a rolling element raceway together with the rolling element guide surface, and a plurality of rolling elements that roll on the rolling element raceway. A slider body having a rolling element return passage that rolls in an unloaded state, and direction change paths that are respectively attached to both ends of the slider body in the moving direction and are connected to both ends of the rolling element raceway and the rolling element return passage are formed. A pair of end caps, and an infinite circulation path through which the plurality of rolling elements roll while circulating from the rolling element raceway, the pair of direction changing paths, and the rolling element return path. The rolling element return passage includes a through hole formed in the slider body, and a passage that fits in the through hole and that the rolling element rolls in an unloaded state. A return guide member, and a margin for allowing the return guide member to extend in the longitudinal direction is provided between the return guide member and the end cap. Yes.

  According to the linear motion guide device according to the first aspect of the present invention, the margin for allowing the return guide member to extend in the longitudinal direction is provided between the return guide member and the end cap. Even if it extends in the longitudinal direction, the margin of the return guide member can be absorbed by this margin. Therefore, it is possible to prevent or reduce the pressing force between the end cap and the return guide member. Therefore, it is possible to prevent or suppress distortion of the infinite circuit.

  Here, in the linear motion guide device according to the first aspect of the present invention, an interposed member that is elastically deformable along the longitudinal direction of the return guide member is disposed in the margin, and the interposed member is It is preferable that the elastic deformation causes the return guide member to contract along the longitudinal direction in accordance with the elongation in the longitudinal direction. If it is such a configuration, the intervention member arranged in the margin is configured to contract along the longitudinal direction according to the elongation in the longitudinal direction of the return guide member due to its elastic deformation, For example, even when the fitting between the through hole and the return guide member inserted therein is a loose fit, the return guide is guided by the intervening member while absorbing the elongation in the longitudinal direction of the return guide member by the margin. The play in the longitudinal direction of the member can be suppressed.

  Further, in the linear motion guide device according to the first invention, the return guide member is divided into a plurality of parts in the longitudinal direction, and the return guide member is disposed between the adjacent divided return guide members. It is preferable that a second margin for allowing elongation in the longitudinal direction is provided. With such a configuration, since the second margin for allowing the return guide member to extend in the longitudinal direction is further provided between the adjacent divided return guide members, the return guide member Even if it extends in the longitudinal direction, it is possible to absorb the elongation more suitably due to the existence of the second margin. Therefore, it is more suitable for preventing or suppressing the distortion of the circulation path.

  Furthermore, a second invention of the present invention is a guide rail having a rolling element guide surface, and is arranged so as to be relatively movable with respect to the guide rail and faces the rolling element guide surface, the rolling element guide surface. And a slider having a load rolling element guide surface that forms a rolling element raceway, and a plurality of rolling elements that roll on the rolling element raceway, the slider rolling when the rolling element is in an unloaded state. A slider body having a rolling element return passage, a pair of end caps that are attached to both ends of the slider body in the moving direction and are formed with direction changing paths respectively connected to both ends of the rolling element raceway and the rolling element return path; And a linear guide device in which an infinite circulation path in which the plurality of rolling elements circulate is circulated from the rolling element raceway, the pair of direction changing paths, and the rolling element return path. The rolling element return passage includes a through hole formed in the slider body, and a return guide member that is fitted in the through hole and forms a passage in which the rolling element rolls in an unloaded state. The return guide member is divided into a plurality of parts in the longitudinal direction, and the return guide member extends in the longitudinal direction between the adjacent divided return guide members. It is characterized by an allowance allowance.

  According to the linear motion guide device according to the second aspect of the present invention, the margin for allowing the return guide member to extend in the longitudinal direction is provided between the adjacent divided return guide members. Even if the member extends in the longitudinal direction, the margin of the return guide member can be absorbed by this margin. Therefore, it is possible to prevent or reduce the pressing force between the end cap and the return guide member. Therefore, it is possible to prevent or suppress distortion of the infinite circuit.

  As described above, according to the present invention, it is possible to provide a linear motion guide device that can prevent or alleviate distortion of an infinite circuit even when members constituting the rolling element return passage extend in the longitudinal direction. Can do.

Embodiments of the present invention will be described below with reference to the drawings as appropriate.
First, a first embodiment of the linear motion guide device according to the present invention will be described.
FIG. 1 is a diagram for explaining a linear guide according to a first embodiment of a linear guide device according to the present invention. FIG. 1 is a front view of the linear guide. In FIG. As shown.

As shown in the figure, the linear guide 10 is laid over a guide rail 12 having a rolling element guide surface 14 and a ball 46, which is a rolling element, so as to be relatively movable with respect to the guide rail 12 so as to roll. And a slider 16 having a load rolling element guide surface 18 facing the moving object guide surface 14.
Specifically, the guide rail 12 is formed with a total of four rolling element guide surfaces 14 on each side of the guide rail 12 along the longitudinal direction (paper surface direction in the figure). The slider 16 includes a slider body 17 and end caps 22 attached to both ends of the slider body 17 in the axial direction.

The continuous shape of the slider body 17 and the end cap 22 in the axial direction (longitudinal direction of the guide rail 12) is a substantially U-shaped cross-sectional shape. On the inner side of the substantially U-shaped slider body 17, a total of four rolling rolling element guide surfaces 18 are formed, which face the rolling element guide surfaces 14 of the guide rail 12.
In the thick portion of the sleeve portion of the slider body 17 having a substantially U-shape, rolling element return passages 20 are formed on the respective load rolling element guide surfaces 18 and extend substantially in parallel with a predetermined interval. The rolling element return passage 20 includes a through hole 32 having a circular cross section that is continuous in the longitudinal direction, and a circulation tube 30 that is a return guide member fitted in the through hole 32.

The circulation tube 30 is made of a synthetic resin, and is a pipe (pipe) having a circular cross-sectional shape continuous in the longitudinal direction. The inside is a passage through which the ball 46 rolls in an unloaded state, and the inner diameter thereof is slightly larger than the diameter of the ball 46, so that the ball 46 can move smoothly in the space in the circulation tube 30. It has become.
When the rolling element return passage 20 is configured by using the pipe-like circulation tube 30 in this way, the diameter of the through hole 32 drilled in the slider 16 can be increased, so that the productivity can be improved. In the first embodiment, the inner and outer diameters of the circulation tube 30 are set so that the through hole 32 of the slider body 17 has a clearance fit (gap amount = about 0.05 to 0.1 m). Has been. With such a configuration, for example, there is an advantage that the circulation tube 30 can be easily inserted as compared with a case where the circulation tube 30 is press-fitted with an interference fit.

Hereinafter, the configuration of the rolling element return passage 20 will be described in more detail.
FIG. 2 is a cross-sectional view taken along line XX in the linear guide of FIG. In addition, the figure (a) abbreviate | omits illustration of the rolling element in the cross section. 2B is an enlarged view of the main part in FIG. 1A, and FIG. 2C shows the position of the circulation tube 30 in FIG. The figure of the state shifted to the side of is shown.

As shown in FIG. 2, the slider 16 has a pair of direction change paths 24 formed in the end cap 22, which are respectively connected to both ends of the load rolling element guide surface 18.
And this linear guide 10 was pinched | interposed between the rolling element guide surface 14 of the guide rail 12, and the load rolling element guide surface 18 of the slider main body 17 which opposes this, as shown to the figure (a). The space forms the rolling element track 26. Then, a total of four infinite circulation paths 28 that are annularly continuous are formed by the pair of direction changing paths 24, the rolling element return paths 20, and the rolling element raceways 26. A plurality of spherical balls 46 as rolling elements are loaded in the endless circuit 28 (not shown in the figure), and the plurality of balls 46 circulate while rolling in the endless circuit 28. It has become.

  Here, in the first embodiment, as shown in the figure, a margin Y (= Ya + Yb) that allows the circulation tube 30 to extend in the longitudinal direction is provided between the circulation tube 30 and the end cap 22. Accordingly, even when the circulation tube 30 constituting the rolling element return passage 20 extends in the longitudinal direction, distortion of the infinite circulation path 28 can be prevented or alleviated.

Here, the amount of margin Y between the circulation tube 30 and the end cap 22 is determined from the following guidelines, for example.
Now, when the circulation tube 30 is made of synthetic resin (plastic), its linear expansion coefficient is about 10 × 10 ⁻⁵ / ° C., and its use limit temperature is about 100 ° C. Therefore, if 80 ° C. is expected as a temperature change from room temperature (about 20 ° C.), the dimensional change rate of the circulation tube 30 is 0.8%. Therefore, the amount of margin Y (hereinafter, the same in the margin in other examples) is sufficient to be 0.8% of the total length of the circulation tube 30. Therefore, in this embodiment, the amount of the margin Y is set to 0.8% of the total length of the circulation tube 30.

Next, functions and effects of the linear guide 10 will be described.
According to the linear guide 10 of the first embodiment, a margin Y (= Ya + Yb) that allows the longitudinal extension of the circulation tube 30 is provided between the circulation tube 30 and the end cap 22. Therefore, even if the circulation tube 30 extends to some extent in the longitudinal direction due to temperature change or swelling, the elongation can be absorbed by this margin Y. Therefore, it is possible to prevent or suppress the end cap 22 and the circulation tube 30 from pressing strongly. Further, even when the elongation of the circulation tube 30 exceeds the margin Y, the pushing force generated between the circulation tube 30 and the end cap 22 can be reduced as compared with the case where there is no margin Y, so that the infinite circulation path 28 deformation can be mitigated. Therefore, distortion (deformation) of the infinite circulation path 28 can be prevented or suppressed.

Next, a second embodiment of the linear motion guide device according to the present invention will be described with reference to FIGS. 3 to 4 as appropriate. Since the second embodiment is the same as the first embodiment except for the points described below, the different points will be described and the other descriptions will be omitted.
FIG. 3 is a diagram for explaining the linear guide according to the second embodiment. FIG. 3A shows a diagram corresponding to FIG. 2A in the first embodiment, and FIG. FIG. 2B shows a diagram corresponding to FIG. FIG. 4 is a diagram for explaining a disc spring arranged as an interposition member. FIG. 4A is a front view thereof, and FIG. 4B is a sectional view taken along line YY in FIG. It is.

As shown in FIG. 3, in the second embodiment, a disc spring 40 made of synthetic resin is disposed as an interposed member in a margin Y provided between one end cap 22 and the circulation tube 30. Is different. The other end cap 22 and the circulation tube 30 are in contact with each other without providing a margin Y.
As shown in FIG. 4, the disc spring 40 has an annular shape when viewed from the front, and has an outer diameter that is substantially the same as the outer diameter of the circulation tube 30 and can be inserted into the through hole 32. . Further, the disc spring 40 is a spring having a substantially frustoconical cylindrical shape, and a large-diameter-side surface of the substantially frustoconical cylinder is in contact with the end surface of the circulation tube 30 so as to be within the margin allowance Y. Is intervened. The disc spring 40 has a small spring constant, and when pressed from the axial direction, the disc spring 40 is a spring that contracts along the longitudinal direction according to the elongation in the longitudinal direction of the circulation tube 30 due to its elastic deformation. Yes.

Next, operations and effects of the linear guide 10 of the second embodiment will be described.
According to the linear guide 10 of the second embodiment, play in the longitudinal direction of the circulation tube 30 can be suppressed by the disc spring 40 in addition to the action and effect of the linear guide 10 of the first embodiment.
That is, in the first embodiment, since the circulation tube 30 is a clearance fit, depending on the assembled state, the circulation tube 30 is one (as shown in FIG. ) To contact with the end cap 22. At this time, there is a margin Y between the other end cap 22 (left side in the figure) and the circulation tube 30. Therefore, even if the position of the circulation tube 30 is shifted as shown in FIG. 2C, the effect of reducing the influence of the elongation of the circulation tube 30 remains unchanged. However, if the circulation tube 30 repeatedly moves left and right in the longitudinal direction within the margin Y while the linear guide 10 is in use, vibration and noise may be generated.

On the other hand, in the second embodiment, since the play in the longitudinal direction of the circulation tube 30 is eliminated by the disc spring 40, movement of the circulation tube 30 in the longitudinal direction during use of the linear guide 10 is prevented. It can be suppressed. Therefore, there is no concern about the occurrence of vibration and noise due to the circulation tube 30 moving repeatedly in the longitudinal direction within the margin Y.
Further, since the extension of the circulation tube 30 can be absorbed by the deformation of the disc spring 40, the pushing force generated between the end cap 22 and the circulation tube 30 is reduced as in the first embodiment. can do. Therefore, distortion (deformation) of the infinite circulation path 28 can be prevented or suppressed.

Next, a third embodiment of the linear guide device according to the present invention will be described with reference to FIGS. Since the third embodiment is the same as the first embodiment except for the points described below, only different points will be described, and other descriptions will be omitted.
FIG. 5 is a diagram for explaining the linear guide of the third embodiment, and FIG. 5 shows a diagram corresponding to FIG. 2A in the first embodiment. FIG. 6 is a view for explaining a circulation tube divided into a plurality of parts. FIG. 6A is a front view thereof, and FIG. 6B is a longitudinal sectional view including an axis.

  In the third embodiment, the circulation tube 30 is divided into a plurality in the longitudinal direction. That is, in the example of the third embodiment, as shown in FIG. 5, the circulation tubes 30A, 30B, 30C are equally divided into three, and between the divided return guide members adjacent to each other, A second margin Y2 (Y2 + Y2 + Y2 = Y) that allows the longitudinal extension of the circulation tube 30 is provided.

Furthermore, in this third embodiment, as shown in FIG. 6, a thin tongue-like portion 42 as an interposed member is integrally provided at one end of each of the circulation tubes 30A, 30B, 30C.
Specifically, as shown in FIG. 6A, the tongue-like portion 42 has a substantially rectangular shape when viewed from the axial direction, and the position where the tongue-like portion 42 is formed is as follows. A pair is provided at opposite positions on both sides in the radial direction. Further, as shown in FIG. 6 (b), the tongue-shaped portion 42 has a protruding amount T in the longitudinal direction of each circulation tube 30A, 30B, 30C, and the length of the second margin Y2 in the longitudinal direction. It is formed to protrude with substantially the same length (T = Y2). The tongue-like portion 42 has an inner portion in the radial direction of each circulation tube 30A, 30B, 30C connected to an end face of each circulation tube 30A, 30B, 30C, and an outer portion in the radial direction. Each is separated from each circulation tube 30A, 30B, 30C by having the cut groove 42k. And each circulation tube 30A, 30B, 30C is built in the slider main body 17 in the state which the tongue-shaped part 42 which makes each pair slightly elastically deformed.

Next, operations and effects of the linear guide 10 of the third embodiment will be described.
According to the linear guide 10 of the third embodiment, the same operations and effects as the second embodiment are achieved.
That is, the expansion of the circulation tube 30 is provided with a second margin Y2 that allows the longitudinal extension of the circulation tube 30 between the circulation tubes 30A, 30B, and 30C. Since each of Y2 has a tongue-like portion 42, the pressing force generated between the end cap 22 and the circulation tube 30 can be reduced as in the first embodiment. Therefore, distortion (deformation) of the infinite circulation path 28 can be prevented or suppressed.

  Each circulation tube 30A, 30B, 30C is incorporated into the slider body 17 with its tongue-like portion 42 slightly elastically deformed. Therefore, as with the second embodiment, each circulation tube 30A, 30B, 30C, The backlash in the longitudinal direction of the 30C can be eliminated. Therefore, there is no concern about the occurrence of vibration and noise due to the circulation tube 30 repeatedly moving in the longitudinal direction within the range of the second margin Y2.

Next, a fourth embodiment of the linear motion guide device according to the present invention will be described with reference to FIGS. 7 to 10 as appropriate. Since the fourth embodiment is the same as the first embodiment except for the points described below, the different points will be described and the other descriptions will be omitted.
FIG. 7 is a view for explaining the linear guide of the fourth embodiment, which shows a view corresponding to FIG. 1 in the first embodiment (note that the end cap is not shown). FIG. 8 is a sectional view taken along line XX in FIG.

  As shown in FIGS. 7 to 8, in the fourth embodiment, a spacer 51 is interposed between the balls 46 in the endless circulation path 28, and the adjacent spacers 51 are adjacent to each other. Are connected by a connecting arm portion 52, and the spacer portion 51 and the connecting arm portion 52 form a belt-like rolling element housing belt 50. The ball 46 is connected by the rolling element housing belt 50 and is rolled. The difference is that the column 62 is constructed.

  A guide groove 60 is provided on the inner surface of the endless circulation path 28 along the endless circulation path 28. In addition, in the part of the rolling element return channel | path 20, the guide groove 60 is provided in the inner surface of the circulation tube 30 (it explains in full detail later). The rolling element housing belt 50 can be smoothly circulated by connecting and guiding the connecting arm portion 52 in the guide groove 60. In order to prevent the ball 46 from falling off when the slider 16 is removed from the guide rail 12 inside the sleeve portions of the substantially U-shaped slider body 17 on the slider body 17 as shown in FIG. Each retainer 70 is provided.

FIG. 10 shows the configuration of the infinite circulation path 28 in the fourth embodiment. In addition, the same figure (a) shows the figure corresponding to FIG. 2 (a) in said 1st embodiment, The same figure (b) is an exploded view of the component in FIG. 10 (a), FIG. 10C is an enlarged view of the main part in FIG.
As shown to Fig.10 (a), in this 4th embodiment, the circulation tube 30 is divided | segmented into two in the longitudinal direction. That is, in the example of the fourth embodiment, the circulation tube 30 is divided into circulation tubes 30D and 30E. Further, the end cap 22 includes an end cap main body 22 a that forms the outer periphery of the direction changing path 24, and an inner peripheral component 22 b that forms the inner periphery of the direction changing path 24. And in this 4th embodiment, as shown in FIG.10 (b), the inner peripheral structure part 22b of the end cap 22 and the circulation tubes 30D and 30E which comprise the rolling element return channel | path 20 are mutually integrated. Has been.

  As shown in an enlarged view in FIG. 10C, a second margin Y3 that allows the longitudinal extension of the circulation tube 30 is provided between the two divided circulation tubes 30D and 30E. ing. Further, the guide groove 60 is provided with chamfers 60a on both sides (proximity portions) of the portion divided by the second margin Y3. As shown in the figure, the chamfer 60a is formed in each of the circulation tubes 30D and 30E so that the width of the guide groove 60 increases toward the mutually opposing end portions.

Next, operations and effects of the linear guide 10 of the fourth embodiment will be described.
According to the linear guide 10 of this 4th embodiment, there exists an effect | action and effect similar to said 2nd embodiment.
In other words, the expansion of the circulation tube 30 is provided with a second margin Y3 that allows the longitudinal extension of the circulation tube 30 between the two circulation tubes 30D and 30E. In addition, the pressing force generated between the end cap 22 and the circulation tube 30 can be eliminated or alleviated. Therefore, distortion (deformation) of the infinite circulation path 28 can be prevented or suppressed.

  Moreover, since each circulation tube 30D and 30E is mutually integrated with the inner peripheral structure part 22b of the end cap 22, respectively, in the longitudinal direction of each circulation tube 30D and 30E like said 2nd embodiment. The backlash can be eliminated. Therefore, there is no fear of generation of vibration and noise due to the circulation tube 30 repeatedly moving in the longitudinal direction within the range of the second margin Y3. Here, in the fourth embodiment, the guide groove 60 is divided by the second margin Y3. However, as shown in FIG. 5C, the chamfer 60 a is provided in the vicinity of the guide groove 60, so that the rolling element containing belt 50 can be prevented or suppressed from being caught at the part where the guide groove 60 is divided.

Next, a fifth embodiment of the linear motion guide device according to the present invention will be described with reference to FIG. 11 as appropriate. The fifth embodiment is a modification of the fourth embodiment, and is the same as the fourth embodiment except for the points described below. Is omitted.
FIG. 11 is a diagram for explaining a linear motion guide device according to the fifth embodiment. FIGS. 11A to 11C are (a) to (c) in FIG. 10 shown in the fourth embodiment. Figures corresponding to are respectively shown.

  As shown in FIG. 5A, in the fifth embodiment, the circulation tube 30 is formed in a half pipe shape along the longitudinal direction thereof, such as an inner circumferential circulation tube 30F, an outer circumferential circulation tube 30G, It is divided into two. That is, the division position of these two circulation tubes 30F and 30G is divided at a position including the axis line in the inner and outer circumferential directions of the infinite circulation path 28, the inner circumferential circulation tube 30F is located on the inner circumferential side, The circulation tube 30G is located on the outer peripheral side. Furthermore, the inner peripheral side circulation tube 30F is further divided into two in the longitudinal direction, and the circulation tubes F1 and F2 are formed.

  And as shown in the same figure (b), the end cap 22 comprises the end cap main body 22a which comprises the outer periphery of the direction change path 24, and the inner periphery of the direction change path 24 like the said 4th embodiment. In the fifth embodiment, the inner peripheral component 22b of the end cap 22 and the inner peripheral side of the rolling element return passage 20 of the half pipe shape are configured. Circulation tubes F1 and F2 are integrated with each other.

  Then, as shown in an enlarged view in FIG. 3C, the inner circumferential circulation tube 30F is arranged between each of the circulation tubes F1 between the two half pipe-like circulation tubes F1 and F2 divided in the longitudinal direction. , F2 is provided with a second margin Y4 which allows the elongation in the longitudinal direction. Further, the guide groove 60 is provided with chamfers 60b on both sides (proximity portions) of a portion divided by the second margin Y4. The chamfer 60b is formed in each of the circulation tubes F1 and F2 such that the width of the guide groove 60 increases toward the mutually opposing end portions.

Further, as shown in FIGS. 4A to 4C, the outer circumferential side circulation tube 30G is extended between the outer circumferential side circulation tube 30G and the end cap 22 in the longitudinal direction. An allowable margin Y5 (Y5 + Y5 = Y) is provided.
Next, operations and effects of the linear guide 10 of the fifth embodiment will be described.
According to the linear guide 10 of the fifth embodiment, the inner peripheral circulation tube 30F has the same operations and effects as the fourth embodiment. Moreover, about the outer peripheral side circulation tube 30G, there exists an effect | action and effect similar to said 1st embodiment.

  That is, in the fifth embodiment, as shown in an enlarged view in FIG. 11C, the second margin Y4 is provided in the proximity portion between the circulation tubes F1 and F2 on the inner peripheral side, and the end cap 22 is provided. Since the margin Y5 is provided between the outer peripheral side circulation tube 30G, the end cap 22 and the circulation tube 30 are pressed against each other when the circulation tube 30 is extended, and the inner circumferential side constituting the circulation tube 30 The mutual pushing force between the circulation tubes F1 and F2 can be eliminated or alleviated. Therefore, distortion (deformation) of the infinite circulation path 28 can be prevented or suppressed. In the fifth embodiment, as shown in an enlarged view in FIG. 11 (c), the guide groove 60 is divided by the second margin Y4, but the divided guide grooves 60 are adjacent to each other. Since the chamfer 60b is provided, it is possible to prevent or suppress the rolling element housing belt 50 from being caught at the part where the guide groove 60 is divided.

Furthermore, according to the linear guide 10 of the fifth embodiment, the circulation tube 30 is divided into half pipes along the longitudinal direction thereof, so that it has a pipe-like portion integrated in an annular shape. do not do. Therefore, when the circulation tube 30 is molded using a synthetic resin, there is an advantage that the mold can be easily released from the mold and can be manufactured at low cost.
Next, a sixth embodiment of the linear motion guide device according to the present invention will be described with reference to FIGS. 12 to 14 as appropriate. The sixth embodiment is a modification of the fourth embodiment, and the fourth embodiment is the same as the fourth embodiment except for the points described below. Therefore, different points will be described, and other descriptions will be given. Is omitted.

FIG. 12 is a diagram for explaining a linear guide according to the sixth embodiment. FIGS. 12A and 12B correspond to FIGS. 10A and 10B in the fourth embodiment. Figures are shown respectively. FIG. 13 is an A arrow view of the end face of the circulation tube 30 in FIG. 12 (a) (or FIG. 14), and FIG. 14 is an enlarged view of the main part of FIG. 12 (a).
As shown in FIG. 12, in this sixth embodiment, the circulation tube 30 has two halved pipes, an inner circumferential circulation tube 30F and an outer circumferential circulation tube 30G, along its longitudinal direction. It is divided into In this example, the inner peripheral circulation tube 30F is not further divided. Then, as shown in FIG. 12B, the end cap 22 constitutes an end cap body 22a constituting the outer periphery of the direction changing path 24 and the inner circumference of the direction changing path 24, as in the fourth embodiment. In the sixth embodiment, one of the inner peripheral components 22b of the end cap 22 and the inner peripheral circulation that constitutes the inner peripheral side of the rolling element return passage 20 are configured in this sixth embodiment. The tube 30F is integrated with each other.

  Here, in the sixth embodiment, since the length of the inner peripheral circulation tube 30F is longer than that in the fifth embodiment, twisting around the center line of the rolling element return passage 20 is likely to occur. . Therefore, in the sixth embodiment, as shown in FIGS. 13 and 14, the inner peripheral component 22b of the end cap 22 on the other side is opposed to the inner peripheral side of the end surface of the inner peripheral circulation tube 30F. In the position to be formed, an alignment convex portion 22c protruding toward the end face side of the inner circumferential circulation tube 30F is formed. And the recessed part 30c for the alignment which can be fitted to this convex part 22c is formed in the end surface inner peripheral side of the inner peripheral side circulation tube 30F, and this positions a mutual position in the expected position. The twisting around the center line of the rolling element return passage 20 is corrected.

  Further, as shown in an enlarged view in FIG. 14, the phase-adjusting convex portion 22 c and the concave portion 30 c are configured to have a margin Y 6 in the longitudinal direction of the circulation tube 30 and are engaged with each other. The circulation tube 30 is allowed to extend in the longitudinal direction. That is, the phase matching convex portion 22c and the concave portion 30c are engaged with each other freely in the longitudinal direction of the circulation tube 30. In addition, a margin Y7 (Y6 = Y7 = Y) is provided between the end of the outer circumference side circulation tube 30G and the end cap 22 so as to have the same clearance as the margin Y6.

Next, operations and effects of the linear guide 10 of the sixth embodiment will be described.
According to the linear guide 10 of the sixth embodiment, the outer peripheral circulation tube 30G has the same operations and effects as those of the first embodiment.
And about the inner periphery side circulation tube 30F, the convex part 22c and the recessed part 30c for phase alignment are comprised with the allowance Y6 in the longitudinal direction of the circulation tube 30, and, thereby, the circulation tube 30 of the circulation tube 30 is provided. Since they are engaged with each other in the longitudinal direction so as to move freely, the extension of the circulation tube 30 is not suppressed by the phase matching convex portions 22c and the concave portions 30c. Therefore, the mutual pressing force between the end cap 22 and the circulation tube 30 when the circulation tube 30 is extended can be eliminated or alleviated. Therefore, distortion (deformation) of the infinite circulation path 28 can be prevented or suppressed.

Next, a seventh embodiment of the linear motion guide device according to the present invention will be described with reference to FIGS. 15 to 16 as appropriate. The seventh embodiment is a modification of the fifth embodiment, and is the same as the fifth embodiment except for the points described below. Is omitted.
15 and 16 are views for explaining a linear guide according to the seventh embodiment. FIG. 15 shows a view corresponding to FIG. 7, and FIGS. 16 (a) to 16 (c) show the fifth guide. FIG. 15 shows diagrams corresponding to FIG. 12 and FIG. 14 shown in the embodiment.

  As shown in FIGS. 15 to 16, in the seventh embodiment, the circulation tube 30 includes an inner circumferential circulation tube 30 </ b> F that is divided into half pipes along the longitudinal direction, and a slider body. The difference is that the rolling element return passage 20 is formed by the through-hole 32 drilled in 17. That is, the rolling element return passage 20 uses the through hole 32 of the slider body 17 as it is on the outer peripheral side, and does not have the circulation tube 30 corresponding to this portion.

  As shown in FIG. 16, the end cap 22 has an end cap body 22 a that constitutes the outer periphery of the direction changing path 24 and an inner circumference that constitutes the inner circumference of the direction changing path 24, as in the fourth embodiment. In the seventh embodiment, the inner peripheral configuration portion 22b of the pair of end caps 22 is a convex portion in which a portion facing the rolling element return passage 20 protrudes into the rolling element return passage 20. Each has a protruding portion 22h that is a portion. In the seventh embodiment, the inner peripheral component 22b and the inner peripheral circulation tube 30F are not integrated.

  And as shown in FIG. 16, the both ends of the inner peripheral side circulation tube 30F are provided with recesses 30d for alignment that can be fitted to the overhanging portion 22h at the portions facing the overhanging portion 22h of the inner peripheral constituting portion 22b. Each is formed. Accordingly, the mutual positions can be aligned with the intended positions, and twisting in the through hole 32 of the inner peripheral side circulation tube 30F around the center line of the rolling element return passage 20 is prevented or suppressed. It has become so.

  Further, as shown in an enlarged view in FIG. 16 (c), the overhanging portion 22h and the recessed portion 30d for phase alignment are configured to have a margin Y8 in the longitudinal direction of the circulation tube 30, and are mutually related. When combined, the circulation tube 30 (inner circumferential circulation tube 30F) is allowed to extend in the longitudinal direction. In other words, the overhanging portion 22h and the recessed portion 30d for phase alignment are engaged with each other freely in the longitudinal direction of the circulation tube 30. In addition, a margin Y9 (Y8 = Y9 = Y) is provided between the end portion of the inner circumferential circulation tube 30F and the end cap 22 so as to have the same clearance as the margin Y8.

As shown in the figure, in the seventh embodiment, the guide groove 60 is divided by a margin Y8, but the divided guide groove 60 is separated from the end portion 22t on the overhang portion 22h side. The position of the end 30t on the inner circumferential circulation tube 30F side is provided so as to rise by being positioned on the outer side in the inner / outer circumferential direction of the infinite circulation path 28.
Next, operations and effects of the linear guide 10 of the seventh embodiment will be described.

According to the linear guide 10 of the seventh embodiment, the through hole 32 of the slider body 17 is used as it is on the outer peripheral side of the rolling element return passage 20, and the circulation tube 30 corresponding to this portion is not provided. Therefore, the number of parts can be reduced as compared with the configuration of the fifth embodiment.
And according to the linear guide 10 of this seventh embodiment, as shown in an enlarged view in FIG. 16 (c), between the overhanging portion 22h of the inner peripheral structure portion 22b and the inner peripheral circulation tube 30F, A margin Y8 is provided, and a margin Y9 is provided between the end cap 22 and the end portion of the inner circumference side circulation tube 30F. Therefore, when the inner circumference side circulation tube 30F extends. The mutual pressing force between the end cap 22 and the inner circumferential circulation tube 30F can be eliminated or alleviated. Therefore, distortion (deformation) of the infinite circulation path 28 can be prevented or suppressed.

  Further, according to the linear guide 10 of the seventh embodiment, although the guide groove 60 is divided by the allowance Y8, the divided guide groove 60 is inward of the end portion 22t on the overhang portion 22h side. Since the position of the end 30t on the side of the circumferential circulation tube 30F is provided so as to be raised by being located outside in the inner and outer circumferential directions of the endless circulation path 28, the rolling element housing belt 50 is separated from the guide groove 60. It is possible to prevent or suppress the possibility of being caught in (the margin Y8 portion).

  That is, in general, the belt-like rolling element housing belt 50 is formed by using a flexible synthetic resin such as an elastomer in a straight line, so that the direction change path 24 returns to the original straight line. I will try. For this reason, the rolling element accommodation belt 50 tends to move along the surface located on the outer peripheral side of the guide groove 60 in the direction change path 24. Therefore, as described above, if the position of the end portion 30t on the inner circumferential circulation tube 30F side is provided so as to rise by being positioned on the outer side in the inner and outer circumferential direction of the endless circulation path 28, the guide groove 60 is configured. Thus, the risk of the rolling element containing belt 50 being caught at the parting portion (the margin Y8 portion) of the guide groove 60 can be prevented or suppressed.

As described above, according to the linear guide 10 of each of the above embodiments, even when the circulation tube 30 that is a member constituting the rolling element return passage 20 extends in the longitudinal direction, the distortion of the infinite circulation passage 28 is caused. Can be prevented or mitigated.
The linear motion guide device according to the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

  For example, in each of the embodiments described above, the linear guide 10 having the ball 46 as the rolling element has been described. However, the present invention is not limited to this, and the present invention is applied to a linear guide using another rolling element, for example, a roller. Provided is a linear motion guide device that is possible and has the same effect, that is, even when a member constituting the rolling element return passage extends in the longitudinal direction, distortion of the infinite circulation path can be prevented or alleviated. Can do.

  Further, for example, in each of the above embodiments, the amount of the margin allowance Y between the circulation tube 30 and the end cap 22 or the second margin allowance Y1 between the adjacent circulation tubes 30 can be set to an appropriate gap. It is. That is, in the above-described embodiment, an example in which the amount of margin Y or the like is 0.8% of the total length of the circulation tube 30 has been described. However, the present invention is not limited to this, and for example, a temperature range in which the linear guide 10 is used. If it is known in advance that N is narrow, it may be a value smaller than this (for example, 0.1% of the total length of the circulation tube 30). In addition, even if a margin allowance equal to or more than the predicted elongation amount is not necessarily provided, if a margin allowance is provided, the margin between the end cap 22 and the circulation tube 30 is larger than when no allowance is provided. Since the generated pushing force can be reduced, the effect of relaxing the deformation of the infinite circuit 28 can be obtained.

It is a figure explaining the linear guide of 1st embodiment of the linear motion guide apparatus which concerns on this invention. It is sectional drawing in the XX line part in the linear guide of FIG. It is a figure explaining the linear guide of 2nd embodiment. It is a figure explaining the linear guide of 2nd embodiment. It is a figure explaining the linear guide of 3rd embodiment. It is a figure explaining the linear guide of 3rd embodiment. It is a figure explaining the linear guide of 4th embodiment. It is a figure explaining the structure of the infinite circuit in 4th embodiment. It is a figure explaining the holder | retainer in the linear guide of 4th embodiment. It is a figure explaining the linear guide of 4th embodiment. It is a figure explaining the linear guide of 5th embodiment. It is a figure explaining the linear guide of 6th embodiment. It is a figure explaining the linear guide of 6th embodiment. It is a figure explaining the linear guide of 6th embodiment. It is a figure explaining the linear guide of 7th embodiment. It is a figure explaining the linear guide of 7th embodiment.

Explanation of symbols

10 Linear guide (linear motion guide device)
DESCRIPTION OF SYMBOLS 12 Guide rail 14 Rolling body guide surface 16 Slider 17 Slider main body 18 Load rolling body guide surface 20 Rolling body return path 22 End cap 24 Direction change path 26 Rolling body track 28 Endless circulation path 30 Circulation tube (return guide member)
32 Through-hole 42 Tongue 46 Ball 50 Rolling element housing belt 51 Spacer 52 Connecting arm part 60 Guide groove 62 Rolling element row 70 Cage Y, Y1 to Y9 Margin, second margin

Claims (4)

A guide rail having a rolling element guide surface, and a load rolling element guide that is disposed so as to be relatively movable with respect to the guide rail and that forms a rolling element track along with the rolling element guide surface. A slider having a surface, and a plurality of rolling elements rolling on the rolling element raceway, the slider having a slider body having a rolling element return passage in which the rolling element rolls in an unloaded state, and A pair of end caps that are attached to both ends of the slider body in the moving direction and that form direction change paths that are respectively connected to both ends of the rolling element raceway and the rolling element return path. A linear motion guide device comprising an infinite circulation path in which the plurality of rolling elements circulate while rolling from a moving body track path, a pair of direction change paths and a rolling element return path,
The rolling element return passage includes a through hole formed in the slider body, and a return guide member that is fitted in the through hole and forms a passage in which the rolling element rolls in an unloaded state. Has been
A linear motion guide device characterized in that a margin for allowing the return guide member to extend in the longitudinal direction is provided between the return guide member and the end cap. In the margin, an interposed member that is elastically deformable along the longitudinal direction of the return guide member is disposed,
2. The linear motion guide device according to claim 1, wherein the intervention member is configured to contract along the longitudinal direction in accordance with the elongation in the longitudinal direction of the return guide member due to elastic deformation thereof. .   The return guide member is divided into a plurality in the longitudinal direction, and a second margin for allowing the return guide member to extend in the longitudinal direction is provided between the adjacent divided return guide members. The linear motion guide device according to claim 1, wherein the linear motion guide device is provided. A guide rail having a rolling element guide surface, and a load rolling element guide that is disposed so as to be relatively movable with respect to the guide rail and that forms a rolling element track along with the rolling element guide surface. A slider having a surface, and a plurality of rolling elements rolling on the rolling element raceway, the slider having a slider body having a rolling element return passage in which the rolling element rolls in an unloaded state, and A pair of end caps that are attached to both ends of the slider body in the moving direction and that form direction change paths that are respectively connected to both ends of the rolling element raceway and the rolling element return path. A linear motion guide device comprising an infinite circulation path in which the plurality of rolling elements circulate while rolling from a moving body track path, a pair of direction change paths and a rolling element return path,
The rolling element return passage includes a through hole formed in the slider body, and a return guide member that is fitted in the through hole and forms a passage in which the rolling element rolls in an unloaded state. Has been
The return guide member is divided into a plurality of portions in the longitudinal direction, and a margin for allowing the return guide member to extend in the longitudinal direction is provided between the adjacent divided return guide members. A linear motion guide device characterized by that.

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