Fixing method of track member and track member with base for motion guide device

Abstract

To use projection welding to fix a track member to a base with high precision.SOLUTION: A fixing method of a track member is performed when a track member 11 of a motion guide device 10 is fixed to a base 31 which is an attachment reference. The track member 11 has a plurality of through holes 11b penetrating in a direction orthogonal to a longitudinal direction and uses welded members 51 which may be respectively installed in the through holes 11b. The welded members 51 are respectively installed in the through holes 11b in a state that a bottom surface of the track member 11 is placed on an upper surface of the base 31. Then, a pair of electrode bars 71a, 71b are disposed on an upper surface of the welded member 51 and a position on a bottom surface of the base 31 and on an extended line in a vertical direction from a contact portion between the welded member 51 and the base 31 to perform projection welding, thereby welding the contact portion between the welded member 51 and the base 31.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a method for fixing a track member and a track member with a base for a motion guide device. [Background technology]

[0002] Motion guide devices, which use rolling elements such as balls and rollers in the guiding section as mechanical elements to guide the linear and curved motion of moving bodies such as tables, are used in a variety of fields, including automobiles, robots, machine tools, semiconductor and liquid crystal manufacturing equipment, and medical devices, as they provide light and agile movement.

[0003] A linear guide, a type of motion guide device, comprises a track member with a rolling element rolling surface formed in the longitudinal direction, and a moving member. The moving member is assembled to the track member so as to be able to move linearly. A plurality of rolling elements are interposed between the track member and the moving member so as to be able to roll in order to reduce frictional resistance. The motion guide device's endless circuit-like circulation path is composed of a loaded rolling element rolling path between the rolling element rolling surface of the track member and the loaded rolling element rolling surface of the moving member, a rolling element return path extending parallel to the loaded rolling element rolling path, and a pair of U-shaped direction change paths connecting the loaded rolling element rolling path and the rolling element return path.

[0004] In the conventional motion guide devices described above, the track members are fixed to the base, which is the mounting target, by using bolt holes formed in the track members. For example, Patent Document 1 below discloses a motion guide device in which a plurality of bolt holes formed in the track members are used to install the track members on the base, and the track members are fixed to the base by the fastening force of bolts that pass through the bolt holes and screw into the base. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-303459 Summary of the Invention [Problem to be solved by the invention]

[0006] However, if drilling or tapping the base could be eliminated when fixing the track member to the base, this would reduce the number of steps, which would be desirable. Furthermore, if the fastening force of bolts could be eliminated when fixing the track member to the base, this would not only reduce the number of steps, but would also be even more desirable, as it would eliminate bolt loosening and increase safety. However, the prior art did not offer a solution to these problems.

[0007] Furthermore, in the method of fixing the track member to the base using bolts, the fastening force of the bolts can cause distortion in the track member, which can adversely affect the weaving characteristics and reduce the guiding accuracy of the motion guide device. Therefore, there has been a demand for a method of fixing the track member to the base with high accuracy without using bolts.

[0008] The present invention has been made in consideration of the problems existing in the prior art described above, and aims to reduce the number of steps by eliminating the need for drilling and tapping on the base and fastening the track members, and to improve safety by eliminating loose bolts.

[0009] The present invention also proposes a new method for fixing a track member to a base, using projection welding. Another object of the present invention is to provide a method for fixing a track member to a base with high precision, and a base-mounted track member for a motion guide device obtained by this method. [Means for solving the problem]

[0010] The method for fixing a track member according to the present invention is a method for fixing a track member of a motion guide device, which includes a track member having a rolling element rolling surface formed along the longitudinal direction, and a movable member assembled to the track member via a plurality of rolling elements so as to be movable relative to the track member, to a base serving as an attachment reference, wherein the track member has a plurality of through holes that penetrate the track member in a direction perpendicular to the longitudinal direction, and a weldable member that can be installed in each of the plurality of through holes is used, and the weldable member is installed in each of the plurality of through holes with the bottom surface of the track member placed on the top surface of the base, and a pair of electrode rods is placed on the top surface of the weldable member and on the bottom surface of the base at positions on a vertical extension line of the contact point between the weldable member and the base, and projection welding is performed to weld the contact point between the weldable member and the base.

[0011] The track member with base for a motion guide device according to the present invention comprises a track member for a motion guide device, the track member comprising a track member on which a rolling element rolling surface is formed along the longitudinal direction, and a moving member assembled to the track member via a plurality of rolling elements so as to be relatively movable, a base serving as an attachment reference for the track member, and a welded member welded to the base by projection welding, and the track member is fixed to the base by the welded member welded to the base, and the track member has a longitudinal direction on which a rolling element rolling surface is formed along the longitudinal direction, and a moving member assembled to the track member via a plurality of rolling elements so as to be relatively movable, a base serving as an attachment reference for the track member, and a welded member welded to the base by projection welding, and the track member is fixed to the base by the welded member welded to the base, and The track member has a plurality of through holes that penetrate in a direction perpendicular to the direction of the welded joint, and the welded parts can be placed in each of the plurality of through holes, and the contact parts between the welded parts and the base are welded and joined by placing the welded parts in each of the plurality of through holes with the bottom surface of the track member placed on the top surface of the base, and then performing projection welding by placing a pair of electrode rods on the top surface of the welded parts and on the bottom surface of the base, each at a position on a vertical extension of the contact parts between the welded parts and the base. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a method for attaching and fixing a track member to a base with few labor hours, high safety, and high precision, and a base-mounted track member for a motion guide device obtained by this method. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is an external perspective view illustrating one embodiment of a linear guide that is a motion guide device to which the present invention can be applied. [Figure 2] 2 is a cross-sectional view for explaining an endless circulation path provided in the linear guide shown in FIG. 1. FIG. [Figure 3] 1 is a cross-sectional view of a track member to which a method for fixing a track member according to an embodiment of the present invention is applied. [Figure 4] 5 is a cross-sectional view illustrating a method for fixing the track member according to the embodiment. FIG. [Figure 5] FIG. 10 is a cross-sectional view after projection welding according to the present embodiment has been performed. [Figure 6] 1A and 1B are diagrams showing examples of various shapes that the welded members or the track members can take in the method for fixing a track member according to the present invention, in which sub-diagram (a) is a diagram illustrating a configuration in which the vertical length of the welded members is changed, sub-diagram (b) is a diagram illustrating a configuration in which the shape of the welded members is changed, and sub-diagram (c) is a diagram illustrating a configuration in which the shape of the welded members 51 is changed and the material of the track member is changed. DETAILED DESCRIPTION OF THE INVENTION

[0014] Preferred embodiments for carrying out the present invention will be described below with reference to the drawings. Note that the following embodiments do not limit the inventions according to the claims, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0015] First, the overall configuration of a linear guide 10 as a motion guide device to which the present invention can be applied will be described with reference to Figures 1 and 2. Here, Figure 1 is an external perspective view illustrating one embodiment of the linear guide 10 as a motion guide device to which the present invention can be applied. Also, Figure 2 is a cross-sectional view for explaining an endless circulation path provided in the linear guide 10 shown in Figure 1.

[0016] A linear guide 10 as a motion guide device to which the present invention can be applied comprises a track member 11 and a moving member 13 slidably assembled to the track member 11 via balls 12 installed as multiple rolling elements.

[0017] The raceway member 11 has a plurality of through holes 11b formed at equal intervals in a direction perpendicular to the longitudinal direction thereof, and a workpiece 51 to be welded, which will be described later and is shown in Fig. 3, can be inserted into each of these through holes 11b. The raceway member 11 is a long member having a cross section perpendicular to the longitudinal direction formed in a substantially rectangular shape, and a rolling element rolling surface 11a is formed on the surface of the raceway member 11 over the entire length thereof as a raceway surface along which the balls 12 roll.

[0018] The track member 11 may be formed to extend linearly or curvedly. In addition, the number of rolling element rolling surfaces 11a illustrated in Figures 1 and 2 is four in total, with two on each side, but the number can be changed as desired depending on the application of the linear guide 10, etc.

[0019] On the other hand, the moving member 13 is provided with loaded rolling element rolling surfaces 13a as raceway surfaces at positions corresponding to the rolling element rolling surfaces 11a. A loaded rolling element rolling path 22 is formed by the rolling element rolling surfaces 11a of the track member 11 and the loaded rolling element rolling surfaces 13a of the moving member 13, and a plurality of balls 12 are sandwiched between them in a loaded state and capable of rolling motion. Furthermore, four rolling element return paths 23 extending parallel to each rolling element rolling surface 11a are formed inside the moving member 13.

[0020] Furthermore, a pair of cover members 17, 17 are installed at both ends in the moving direction of the moving member 13. Each of the pair of cover members 17, 17 is provided with a direction change path 25. The direction change path 25 is configured to connect the end of the rolling element return path 23 and the end of the loaded rolling element rolling path 22. Therefore, a single endless circulation path is configured by the combination of one loaded rolling element rolling path 22 and one rolling element return path 23 and the pair of direction change paths 25, 25 connecting them (see FIG. 2).

[0021] Furthermore, by installing a plurality of balls 12 in an infinite circulation path consisting of a loaded rolling element rolling path 22, a rolling element return path 23, and a pair of direction change paths 25, 25 so that they can circulate infinitely, the moving member 13 can move back and forth relative to the longitudinal direction of the track member 11.

[0022] Furthermore, a pair of end seals 15, 15 are provided as sealing members on each of the pair of cover members 17, 17 so as to close the gap between the movable member 13 and the track member 11 on the outside of the pair of direction change paths 25, 25. The end seals 15 can be provided with lip portions at the contact points with the track member 11, and the lip portions or the end seals 15 themselves slide against the track member 11 without any gaps, thereby providing the linear guide 10 with a dustproof effect.

[0023] 1 and 2 is sandwiched between the movable member 13 and the pair of lid members 17, 17. This return plate (not shown) has a first function of closing the installation surface of the lid member 17 on the movable member 13, and by closing the gap that exists between the movable member 13 and the lid member 17, it plays a role in enhancing the airtightness between the movable member 13 and the lid member 17. Furthermore, as a second function, the return plate (not shown) is formed with an inner circumferential road surface 25b of the direction change path 25, which cooperates with an outer circumferential road surface 25a formed on the lid member 17 to form the direction change path 25.

[0024] The general configuration of the linear guide 10 as a motion guide device to which the present invention can be applied has been described above. Next, the specific configuration of the track member 11 and the base 31, which is the fixed member, to which the method for fixing a track member according to this embodiment is applied will be described with reference to FIG.

[0025] 3 is a cross-sectional view of a track member 11 for which a method for fixing a track member according to this embodiment is carried out. In the method for fixing a track member according to this embodiment, the track member 11 is placed so that its bottom surface contacts the upper surface of a base 31, which serves as an attachment reference. The track member 11 also has a plurality of through holes 11b formed in a direction perpendicular to its longitudinal direction (one through hole 11b is shown in FIG. 3). Furthermore, a workpiece 51 to be welded is inserted into the through holes 11b.

[0026] In this embodiment, the track member 11 is made of a metal material, for example, high-carbon steel such as S55C, which has excellent wear resistance. The base 31 may be made of a metal material, for example, the same type of iron-based metal as the track member 11, or a non-ferrous metal alloy such as an aluminum alloy. However, since the welded member 51 is welded to the base 31 by projection welding, it is desirable that the welded member 51 be made of the same or the same type of metal material as the base 31.

[0027] Through hole 11b has, in order from the bottom, an expanded portion 11c, a small diameter portion 11d, and a large diameter portion 11e. Expanded portion 11c has a larger diameter than small diameter portion 11d, and large diameter portion 11e has a larger diameter than small diameter portion 11d. Therefore, through hole 11b is formed by combining three types of holes formed with each diameter.

[0028] The welded member 51 has, in order from the bottom, an anti-flange portion 51c, a shaft-like portion 51d, and a flange portion 51e. The shaft-like portion 51d has a diameter that is approximately the same as or smaller than the diameter of the small-diameter portion 11d in the through hole 11b. The flange portion 51e has a diameter that is approximately the same as the diameter of the large-diameter portion 11e in the through hole 11b. On the other hand, the anti-flange portion 51c has a continuously tapered shape formed so that the diameter decreases from the boundary with the shaft-like portion 51d to the bottom.

[0029] The welded member 51 is formed so that the vertical length of the combined portion of the anti-flange portion 51c and the shaft-like portion 51d is longer than the vertical length of the combined portion of the expanded portion 11c and the small diameter portion 11d in the through hole 11b. The vertical length of the flange portion 51e is also formed so as to be approximately the same as the vertical length of the large diameter portion 11e in the through hole 11b.

[0030] That is, in the initial state where the welded members 51 are simply inserted into the through hole 11b, the flange portion 51e of the welded members 51 slightly protrudes from the top surface of the track member 11 toward above the through hole 11b, thereby forming a convex portion on the top surface of the track member 11. After projection welding, which will be described later, is performed, the top surface of the welded members 51 is formed to be flush with the top surface of the track member 11. Furthermore, with the welded members 51 inserted into the through hole 11b, an expanded space 61 is formed between the anti-flange portion 51c of the welded members 51 and the expanded portion 11c of the through hole 11b.

[0031] Furthermore, the outer peripheral surface of the welded member 51 in this embodiment is covered with an insulating coating 41 that has an anti-current effect. Therefore, when the welded member 51 is inserted into the through hole 11b, the track member 11 and the welded member 51 are electrically insulated from each other. This makes it possible to prevent electricity from flowing through the track member 11 and causing a short circuit when the welded member 51 and the base 31 are electrically connected during projection welding, which will be described later. Note that the insulating coating 41 may be formed on the inner peripheral surface of the through hole 11b, as long as it can insulate the track member 11 and the welded member 51 from each other.

[0032] A pair of electrodes 71a, 71b are arranged on the top surfaces of the workpieces 51 to be welded and on the bottom surface of the base 31, on a vertical extension of the contact point between the workpieces 51 to be welded and the base 31. The pair of electrodes 71a, 71b shown in Fig. 3 is in a state before projection welding is performed, and is therefore shown separated from the top surfaces of the workpieces 51 to be welded and the bottom surface of the base 31. The pair of electrodes 71a, 71b consists of an upper electrode 71a located on the top surface side of the workpieces 51 to be welded and a lower electrode 71b located on the bottom surface side of the base 31. The upper electrode 71a and the lower electrode 71b can each move in the vertical direction.

[0033] The specific configurations of the track member 11 and the base 31, which is the member to be fixed, to which the method for fixing a track member according to this embodiment is applied have been described above using Fig. 3. Next, the method for fixing a track member according to this embodiment will be described with reference to Figs. 4 and 5.

[0034] FIG. 4 is a cross-sectional view illustrating a method for fixing a track member according to this embodiment. Similar to FIG. 3, FIG. 4 shows a state in which a track member 11 is placed on the upper surface of a base 31, which serves as an attachment reference. Furthermore, a workpiece 51 is inserted into a through-hole 11b formed in the track member 11. In the method for fixing a track member according to this embodiment, first, the upper electrode rod 71a and the lower electrode rod 71b are each moved vertically from the state shown in FIG. 3 to the state shown in FIG. 4, so that the upper electrode rod 71a abuts against the upper surface of the workpiece 51 and the lower electrode rod 71b abuts against the bottom surface of the base 31. With the upper electrode rod 71a abutting against the upper surface of the workpiece 51 and the lower electrode rod 71b abutting against the bottom surface of the base 31, the workpiece 51 and the base 31 are sandwiched between the pair of electrodes 71a and 71b.

[0035] From this state, the contact portion of the welded member 51 and the base 31 is welded and joined by projection welding. That is, a current is passed through the pair of electrode rods 71a, 71b to energize the welded member 51 and the base 31, and pressure is applied to the welded member 51 and the base 31 by the pair of electrode rods 71a, 71b, thereby welding and joining the contact portion of the anti-flange portion 51c of the welded member 51 and the base 31.

[0036] Here, projection welding is a type of resistance welding in which a projection (protruding portion) is provided at the welding point of the base material, and current is concentrated at the protruding portion to heat the portion by resistance heat, while simultaneously applying pressure to the welding point to join them. In this embodiment, the lower tip of the anti-flange portion 51c of the welded member 51 corresponds to the protruding portion in projection welding.

[0037] FIG. 5 is a cross-sectional view after projection welding according to this embodiment is performed. The contact area between the workpiece 51 and the base 31, which is the joint, is heated by resistance heat, forming a nugget 62. Furthermore, a portion of the metal melted by projection welding becomes a weld burr 62a around the joint. In this case, the space 61 functions as an expanded void through which the weld burr 62a can escape. Therefore, the weld burr 62a, which may impede stable joining of the workpiece 51 and the base 31, can be contained within the space 61, thereby preventing malfunctions of the linear guide 10. The inventors have confirmed that the weld burr 62a generated by projection welding spreads evenly in the circumferential direction, as shown in FIG. 5 . Therefore, it is desirable to form the space 61 to accommodate the occurrence of such a weld burr 62a.

[0038] By welding and joining the contact portions of the welded members 51 and the base 31 by projection welding, the track member 11 is sandwiched vertically between the flange portion 51e of the welded members 51 and the base 31, restricting its movement in the vertical direction. Furthermore, the track member 11 is sandwiched horizontally between the flange portion 51e of the welded members 51 inserted into one through hole 11b and the flange portion 51e of the welded members 51 inserted into the other through hole 11b, restricting its movement in the horizontal direction. Therefore, the track member 11 can be reliably fixed to the upper surface of the base 31 while maintaining its horizontality and linearity.

[0039] Furthermore, as a result of projection welding, a portion of the contact area of ​​the welded member 51 melts and is pressurized, slightly shortening its vertical length, so that the top surfaces of the track member 11 and the welded member 51 become flush with each other. This configuration is preferable because it does not impede the operation of the moving member 13, which performs linear reciprocating motion in the longitudinal direction of the track member 11. In particular, the general linear guide 10 described with reference to FIGS. 1 and 2 is provided with a pair of end seals 15, 15 as sealing members to seal the gap between the moving member 13 and the track member 11 and to provide a dust-proof effect. However, in this embodiment, the top surfaces of the track member 11 and the welded member 51 become flush with each other after projection welding, so the dust-proof effect of the end seals 15 as sealing members is fully exhibited. In other words, according to the method for fixing a track member of this embodiment, the flange portion 51e of the welded member 51 is fitted into the large diameter portion 11e of the through hole 11b, thereby making it possible to effectively prevent foreign matter such as dust and chips from entering the through hole 11b when the linear guide 10 is in operation.

[0040] After the projection welding described above is performed, the energized state of the pair of electrode rods 71a, 71b is released, and the pair of electrode rods 71a, 71b are separated from the workpiece 51 and the base 31. This completes the method for fixing a track member according to this embodiment.

[0041] As described above, the method for fixing a track member according to this embodiment fixes the track member 11 to the base 31 by projection welding instead of bolts, eliminating the need for thread machining of the mounting surface, which was previously performed. Furthermore, because no bolt fastening using a threaded joint is involved, distortion of the track member 11 due to this can be prevented, and the track member 11 can be fixed to the base 31 with high precision.

[0042] The track member with a base for a motion guide device according to the present invention can be manufactured by the track member fixing method according to the present invention described above. This track member with a base for a motion guide device includes a track member for a motion guide device, the track member having a rolling element rolling surface formed along the longitudinal direction, and a moving member assembled to the track member via a plurality of rolling elements so as to be relatively movable, a base serving as an attachment reference for the track member, and welded members welded to the base by projection welding, and the track member is fixed to the base by the welded members welded to the base, and the track member has a longitudinal direction The track member has a plurality of through holes passing through in a direction perpendicular to the track member, the members to be welded can be placed in each of the plurality of through holes, and the contact portions between the members to be welded and the base are welded and joined by placing the members to be welded in each of the plurality of through holes with the bottom surface of the track member placed on the top surface of the base, and then performing projection welding by placing a pair of electrodes on the top surfaces of the members to be welded and on the bottom surface of the base, respectively, at positions on an extension line in the vertical direction of the contact portions between the members to be welded and the base. A base-mounted track member for a motion guide device according to the present invention is a track member fixed to a base with high precision.

[0043] While the preferred embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the scope described in the above embodiments. Various modifications and improvements can be made to the above embodiments.

[0044] For example, Figure 6 shows examples of various shapes that can be taken by the welded member 51 or the track member 11 in the method for fixing a track member according to the present invention, where sub-figure (a) in the figure is a diagram illustrating a configuration in which the vertical length of the welded member 51 is changed, sub-figure (b) is a diagram illustrating a configuration in which the shape of the welded member 51 is changed, and sub-figure (c) is a diagram illustrating a configuration in which the shape of the welded member 51 is changed and the material of the track member 11 is changed.

[0045] In the above-described embodiment, a method for fixing a track member in which the upper surface of the track member 11 and the upper surface of the welded member 51 are flush with each other by projection welding has been described. However, the method for fixing a track member according to the present invention is not limited to the method of the above-described embodiment. For example, as shown in FIG. 6 (a), the vertical length of the flange portion 51e of the welded member 51 according to another embodiment may be shorter than the vertical length of the large-diameter portion 11e of the through hole 11b. As described above, in the present invention, it is sufficient that the upper surface of the welded member 51 does not protrude beyond the upper surface of the track member 11 after projection welding. By employing a structure in which the upper surface of the welded member 51 does not protrude beyond the upper surface of the track member 11, the track member 11 can be fixed to the base 31 without affecting the reciprocating linear motion of the moving member 13.

[0046] For example, as shown in the partial view (b) of FIG. 6, the tip of the anti-flange portion 51c of the welded member 51 according to another embodiment may have a spherical shape that is approximately hemispherical toward the bottom. Furthermore, as shown in the partial view (c) of FIG. 6, the tip of the anti-flange portion 51c of the welded member 51 according to another embodiment may have a tapered shape that is approximately conical toward the bottom. Thus, in the present invention, the tip of the anti-flange portion 51c of the welded member 51 may have a protrusion that abuts against the contact portion between the welded member 51 and the base 31. In other words, various shapes can be adopted for the welded member of the present invention, which provides the effect of increasing the degree of freedom in design.

[0047] 6(c), the track member 11 according to another embodiment may be made of ceramic. As described above, in the present invention, the track member 11 and the base 31 are not directly welded together, so the track member 11 does not need to be made of the same or the same type of metal material as the base 31, and a non-conductive material such as ceramic can be used. In this case, it is not necessary to cover the inner circumferential surface of the through hole 11b of the track member 11 or the outer circumferential surface of the member to be welded 51 with the insulating coating 41. The track member of the present invention can be made of any material in addition to the metal materials and non-conductive materials described above.

[0048] In the above-described embodiment, the expanded portion 11c of the through hole 11b has a constant diameter, but the expanded portion 11c may have any shape as long as there is an expanded space 61 near the joint for allowing some of the molten metal to escape. Furthermore, if conditions are such that welding burrs 62a are unlikely to occur on the anti-flange portion 51c of the welded members 51 when performing the projection welding of the present invention, the through hole 11b does not need to have the expanded portion 11c. In this case, the through hole 11b can be formed by combining two types of holes: a small diameter portion 11d and a large diameter portion 11e.

[0049] Furthermore, in the above-described embodiment, the plurality of through holes 11b are formed with a space 61 that is larger than the small-diameter hole that constitutes the through hole 11b near the tip of the shaft-shaped portion 51d that constitutes the welded member 51 on the side opposite to the flange portion 51c. However, this space 61 may also be formed on the side of the base 31. That is, the base according to the present invention may be formed so that the portion that comes into contact with the tip of the shaft-shaped portion 51d that constitutes the welded member 51 on the side opposite to the flange portion 51c has a space that is larger than the small-diameter hole that constitutes the through hole 11b.

[0050] Furthermore, the present invention is not limited to the shapes of the track member 11 and base 31 in the above-described embodiment, but is applicable to track members and bases of various shapes.

[0051] Furthermore, projection welding in the present invention can be performed at multiple points simultaneously with the bottom surface of the track member 11 placed on the upper surface of the base 31.

[0052] It is clear from the claims that the technical scope of the present invention includes forms to which the above-mentioned modifications or improvements have been made. [Explanation of symbols]

[0053] 10 linear guide (motion guide device), 11 raceway member, 11a rolling element rolling surface, 11b through hole, 11c expansion portion, 11d small diameter portion, 11e large diameter portion, 12 ball (rolling element), 13 moving member, 13a loaded rolling element rolling surface, 15 end seal, 17 cover member, 22 loaded rolling element rolling path, 23 rolling element return passage, 25 direction change path, 25a outer peripheral road surface, 25b inner peripheral road surface, 31 base, 41 insulating coating, 51 welded member, 51c anti-flange portion, 51d axial portion, 51e flange portion, 61 space, 62 nugget, 62a welding burr, 71a upper electrode rod (electrode rod), 71b lower electrode rod (electrode rod).

Claims

1. A method for fixing a track member of a motion guide device, the method comprising: a track member having a rolling element rolling surface formed along a longitudinal direction; and a moving member assembled to the track member via a plurality of rolling elements so as to be relatively movable; the method being executed when fixing the track member to a base serving as an attachment reference; the track member has a plurality of through holes that penetrate in a direction perpendicular to the longitudinal direction, Using a welded member that can be installed in each of the plurality of through holes, a pair of electrode rods is placed on the top surface of the base, and a pair of electrode rods is placed on the top surface of the welded parts and on the bottom surface of the base, respectively, at positions on a vertical extension line of the contact point between the welded parts and the base, and projection welding is performed to weld and join the contact point between the welded parts and the base.

2. The method for fixing a track member according to claim 1, A method for fixing a track member, characterized in that when the contact portions of the welded members and the base are welded together, the upper surfaces of the welded members do not protrude above the upper surface of the track member.

3. The method for fixing a track member according to claim 1, A method for fixing a track member, characterized in that when the contact portions of the workpieces and the base are welded together, the upper surfaces of the workpieces become flush with the upper surface of the track member.

4. The method for fixing a track member according to any one of claims 1 to 3, Each of the plurality of through holes is formed by combining two types of holes with different diameters, that is, a small diameter hole on the side that contacts the base and a large diameter hole on the opposite side to the side that contacts the base, and the welded members that can be installed in each of the plurality of through holes have a bolt shape that is configured by a shaft-shaped portion that is installed in a small-diameter hole that constitutes the through hole and a flange portion that is installed in a large-diameter hole that constitutes the through hole, a method for fixing a track member, the method comprising: placing the track member on the upper surface of the base, installing the welded members each having a bolt shape in each of the plurality of through holes, and placing a pair of electrode rods at the upper surface of the flange portion constituting the welded members and at a position on the bottom surface of the base on an axial extension of the shaft-shaped portion constituting the welded members, thereby welding and joining the tip of the shaft-shaped portion constituting the welded members on the side opposite the flange portion to the upper surface of the base.

5. The method for fixing a track member according to claim 4, A method for fixing a track member, wherein the tip of the shaft-shaped portion constituting the welded member on the side opposite the flange portion is tapered.

6. The method for fixing a track member according to claim 4, A method for fixing a track member, wherein the tip of the shaft-shaped portion constituting the welded member on the side opposite the flange portion is spherical.

7. The method for fixing a track member according to claim 4, A method for fixing a track member, characterized in that at least one of the outer peripheral surface of the workpiece to be welded or the inner peripheral surface of the through hole is covered with an insulating coating having an anti-current effect.

8. The method for fixing a track member according to claim 4, a plurality of through holes formed in the vicinity of where the tip of the shaft-shaped portion constituting the welded member on the side opposite the flange portion is located, the through holes being formed with a space that is larger than the small-diameter hole that constitutes the through hole.

9. The method for fixing a track member according to claim 4, a portion of the base that comes into contact with the tip of the shaft-shaped portion that constitutes the welded member on the side opposite the flange portion is formed to have a space that is larger than the small-diameter hole that constitutes the through hole.

10. The method for fixing a track member according to claim 4, the base and the workpieces are made of metal materials, A method for fixing a track member, wherein the track member is made of a material different from the metal material.

11. The method for fixing a track member according to claim 1, A method for fixing a track member, wherein the projection welding is performed simultaneously at multiple points with the bottom surface of the track member placed on the upper surface of the base.

12. a track member of a motion guide device including: a track member having a rolling element rolling surface formed along a longitudinal direction; and a moving member assembled to the track member via a plurality of rolling elements so as to be relatively movable; a base serving as a mounting reference for the track member; a welded member to be welded to the base by projection welding; The track member is fixed to the base by the welded member welded to the base, the track member has a plurality of through holes that penetrate in a direction perpendicular to the longitudinal direction, The welded members can be placed in each of the plurality of through holes, a base-mounted track member for a motion guide device, characterized in that the contact portions between the welded members and the base are welded and joined by placing the welded members in each of the plurality of through holes with the bottom surface of the track member placed on the top surface of the base, and then performing projection welding by placing a pair of electrode rods on the top surfaces of the welded members and on the bottom surface of the base, each at a position on an extension line in the vertical direction of the contact portions between the welded members and the base.

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