Linear motion guide device and manufacturing method thereof

Abstract

To provide a linear motion guide device that can ensure smooth ball movement while mitigating impact force regardless of the behavior of a ball entering a raceway surface, and that is low cost, and a manufacturing method thereof.SOLUTION: In a linear guide device, when a plane passing through a widthwise center of a slider body and a longitudinal axial line of a guide rail is defined as a vertical center plane CP, a plane perpendicular to the vertical center plane CP and passing through a center line of a straight part of a rolling passage is defined as a horizontal reference plane HP, and a plane parallel to the vertical center plane CP and intersecting a chamfered part is defined as a vertical reference plane VP, in a cross section perpendicular to the center line of the straight part, the surface of the chamfered part lies on a rotation locus centered at a point O2 shifted along the horizontal reference plane HP away from a first raceway surface with respect to a groove bottom center O1 of the first raceway surface, and the minimum radius of the rotation locus is larger than a groove bottom radius r of the first raceway surface.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a linear guide device and a method for manufacturing the same.

Background Art

[0002] A linear guide device that linearly guides a guided object while infinitely circulating rolling elements such as rollers and balls inside is an important mechanical element that greatly affects the motion accuracy of semiconductor manufacturing equipment, ultra-precision processing machines, ultra-precision measuring instruments, and the like.

[0003] The linear guide device includes a guide rail and a slider body. A rail-side rolling element raceway groove is provided in the guide rail. A slider-side rolling element raceway groove facing the rail-side rolling element raceway groove is provided in the slider body, and the guide rail supports the slider body so that it can move axially through the rolling of a plurality of rolling elements disposed in a rolling passage formed between the slider-side rolling element raceway groove and the rail-side rolling element raceway groove. The linear guide device further includes a rolling element return passage provided in the slider body so as to be substantially parallel to the rolling passage, and a direction conversion passage provided in end caps attached to both ends in the moving direction of the slider body to communicate the rolling passage and the rolling element return passage.

[0004] When the rolling elements of the linear guide device infinitely circulate through the rolling passage, the direction conversion passage, and the rolling element return passage, periodic minute vibrations (hereinafter referred to as rolling element passing vibrations) occur, which greatly affect the motion accuracy of the above-described devices. The rolling element passing vibration occurs when the load is released as the rolling element rolling in the rolling passage (load region) under a load due to preload or external load exits the load region to the rolling element circulation path (non-load region), or conversely, when a new load is applied when entering the load region from the non-load region.

[0005] To suppress this rolling element passing vibration, inclined surfaces called crowning are provided at both ends of the slider-side rolling element raceway groove forming the rolling passage. By gradually changing the load associated with the entry and exit of the rolling element into and out of the load region by crowning, the rolling element passing vibration can be reduced.

[0006] Patent Document 1 discloses a linear motion guide bearing including a first crowning having a curved surface shape formed with a large radius of curvature such that the inclined portions provided at both ends of the slider-side rolling element raceway groove are continuously inclined gently from the slider-side rolling element raceway groove, a second crowning that is adjacent to the first crowning and has a steeper inclination than the first crowning extending toward the inner peripheral surface of the direction changing path and is shorter than the first crowning in the axial direction, and an inclined surface provided between the second crowning and the end surface of the slider body and inclined more than the first crowning and the second crowning.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] By the way, in the slider body of Patent Document 1, in a cross section obtained by cutting the slider-side rolling element raceway groove with a plane extending in the vertical direction, horizontal direction, etc. passing through the axis of the slider-side rolling element raceway groove, the shape at the end portion is uniform in any cross section. For this reason, it is necessary to form the first crowning, the second crowning, and the inclined surface having a common shape in all cross sections, which may cause premature wear of the processing tool and increase the manufacturing cost of the linear motion guide bearing.

[0009] The present invention has been made in view of the above problems, and an object thereof is to provide a linear motion guide device and a manufacturing method thereof that are low in cost and can ensure smooth movement of balls while reducing impact force regardless of the behavior of the balls entering the raceway surface.

Means for Solving the Problems

[0010] The linear motion guide device of the present invention is A guide rail, A slider arranged to move relative to the guide rail in the longitudinal direction, A linear guide device comprising a plurality of rolling elements arranged to roll freely along a rolling passage formed between the guide rail and the slider, The slider, A slider body having a raceway groove facing the raceway groove of the guide rail to form a rolling passage for the rolling elements and a return passage for the rolling elements, An end cap having a direction-changing passage connecting the return passage and the rolling passage, The raceway groove of the slider body has a first raceway surface on the central portion side of the rolling passage and a second raceway surface on the end portion side of the rolling passage, The second raceway surface has a first inclined surface extending from the first raceway surface to the end face of the slider body and a chamfered portion extending to the end face of the slider body without contacting the first inclined surface, When a plane passing through the center in the width direction of the slider body and the longitudinal axis of the guide rail is defined as a vertical center plane CP, a plane perpendicular to the vertical center plane CP and passing through the center line of the straight portion of the rolling passage is defined as a horizontal reference plane HP, and a plane parallel to the vertical center plane CP and intersecting the chamfered portion is defined as a vertical reference plane VP, The surface of the chamfered portion is on a rotational locus centered at a point O2 shifted along the horizontal reference plane HP so as to be separated from the first raceway surface with respect to the center line O1 of the straight portion of the rolling passage in a cross section perpendicular to the center line of the straight portion, and the minimum radius of the rotational locus is larger than the groove bottom radius r of the first raceway surface. This is the feature.

[0011] A method for manufacturing the linear guide device of the present invention, A guide rail, A slider arranged to move relative to the guide rail in the longitudinal direction, A method for manufacturing a linear guide device comprising a plurality of rolling elements arranged to roll freely along a rolling passage formed between the guide rail and the slider, The slider, A slider body having a raceway groove that is disposed opposite to the raceway groove of the guide rail and forms a rolling path for the rolling elements, and a return path for the rolling elements; An end cap having a direction-changing path that connects the return path and the rolling path, The raceway groove of the slider body has a first raceway surface on the center side of the rolling path and a second raceway surface on the end side of the rolling path, The second raceway surface has a first inclined surface that extends from the first raceway surface to the end surface of the slider body, and a chamfered portion that extends to the end surface of the slider body without contacting the first inclined surface, A grinding tool or a cutting tool having a tapered rotation locus is rotated around a machining axis O2 that is translated in parallel so as to be separated from the first raceway surface with respect to the center line O1 of the straight portion of the rolling path, and is brought close to the second raceway surface along the machining axis O2, and the chamfered portion is formed by cutting a part of the first inclined surface.

Advantages of the Invention

[0012] According to the present invention, it is possible to provide a linear motion guide device and a method for manufacturing the same, which are low-cost, while ensuring smooth movement of the balls while reducing the impact force regardless of the behavior of the balls entering the raceway surface.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this specification, terms indicating directions (such as upward and downward) refer to the respective directions in FIG. 2 unless otherwise specified. Also, the "longitudinal direction" refers to the longitudinal direction of the guide rail or the slider.

[0015] (First Embodiment) FIG. 1 is a perspective view showing a linear guide device according to the first embodiment of the present invention. FIG. 2 is a front view of the slider body of the linear guide device in FIG. 1 as seen from the longitudinal direction of the guide rail, but the end caps are omitted. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2, but the retainer 4 and the retainer groove 10Ba are omitted. In FIG. 2, a plane passing through the center in the width direction of the slider body 2A and the longitudinal axis of the guide rail 1 is defined as a vertical center plane CP, a plane that is orthogonal to the vertical center plane CP and passes through the center line O1 of the straight portion of a pair of rolling passages 13A arranged on both sides with the guide rail 1 interposed therebetween is defined as a horizontal reference plane HP. Also, a plane that is shifted from the center line O1 of the straight portion of the rolling passage 13A to the first upper track surface side and is orthogonal to the horizontal reference plane HP is defined as a vertical reference plane VP. However, the vertical reference plane VP is parallel to the vertical center plane CP and is a plane that intersects the second inclined surface and the third inclined surface described later. Although details will be described later, each component configuration will be described using the vertical reference plane VP and the horizontal reference plane HP corresponding to one of the rolling passages 13A.

[0016] Along a guide rail 1 with a substantially rectangular cross-sectional shape extending linearly, a slider 2 with a substantially U-shaped cross-sectional shape is assembled so as to be movable in the longitudinal direction of the guide rail 1. On the ridge portions where the left and right side surfaces 1a, 1a and the upper surface 1b of the guide rail 1 in the width direction intersect, track grooves 10A, 10A each consisting of a concave groove with a substantially 1 / 4 arc-shaped cross-sectional shape are formed along the longitudinal direction.

[0017] Also, on the substantially central portions in the vertical direction of the left and right side surfaces 1a, 1a of the guide rail 1 in the width direction, track grooves 10B, 10B each consisting of a concave groove with a substantially semi-circular cross-sectional shape are formed along the longitudinal direction. Further, on the groove bottoms of the track grooves 10B, 10B, a retainer groove 10Ba (wire groove) for accommodating a part of the retainer 4 and guiding the retainer 4 when the slider 2 moves is formed along the longitudinal direction across both ends of the movement region of the slider 2 (for example, between both ends in the longitudinal direction of the guide rail 1). The cross-sectional shape of the retainer groove 10Ba is, for example, substantially rectangular.

[0018] The slider 2 also includes a flat body portion 7 facing the upper surface 1b of the guide rail 1 and two leg portions 6, 6 extending downward from both left and right sides of the body portion 7 and facing the side surface 1a. Since the angle formed by the body portion 7 and the leg portions 6, 6 is substantially a right angle, the cross-sectional shape of the slider 2 is substantially U-shaped. Further, the slider 2 is movably attached to the guide rail 1 so as to sandwich the guide rail 1 between both leg portions 6, 6.

[0019] The slider 2 includes a slider body 2A, and end caps 2B, 2B detachably attached to both end portions (both end portions in the longitudinal direction) of the slider body 2A. Further, side seals 5, 5 are attached to both end portions of the slider 2 (outer end faces in the longitudinal direction of each end cap 2B), which are in sliding contact with the outer surfaces (upper surface 1b and side surfaces 1a, 1a) of the guide rail 1 to seal the portion facing the longitudinal end face side of the opening of the gap between the guide rail 1 and the slider 2. Under seals 8, 8 are attached to the lower portion of the slider 2 to seal the portion facing the lower surface side of the slider 2 of the opening of the gap between the guide rail 1 and the slider 2. These side seals 5, 5 and under seals 8, 8 prevent foreign matter from entering the gap from the outside and prevent the lubricant from leaking from the gap to the outside.

[0020] Furthermore, at the corners and the substantially central portion in the vertical direction on the inner side surfaces of the left and right leg portions 6, 6 of the slider body 2A, there are formed groove portions 11A, 11A, 11B, 11B (hereinafter, 11 may be used as a collective reference sign for these) formed of concave grooves having a substantially semi-circular cross-sectional shape facing the track grooves 10A, 10A, 10B, 10B (hereinafter, 10 may be used as a collective reference sign for these) of the guide rail 1. Also, rolling passages 13A, 13A, 13B, 13B (hereinafter, 13 may be used as a collective reference sign for these) having a substantially circular cross-section are respectively formed between the track grooves 10 of the guide rail 1 and the track grooves 11 of the slider 2, and these rolling passages extend in the longitudinal direction.

[0021] A plurality of rolling elements 3 (balls) are loaded in the rolling passage 13 while being held by a cage 4 so as to be freely rotatable. Through the rolling of the rolling elements 3 in the rolling passage 13, the slider 2 is guided by the guide rail 1 and is movable in the longitudinal direction. The cage 4 is formed of, for example, a wire and holds the rolling elements 3 to prevent the rolling elements 3 from falling off the slider 2 before being assembled to the guide rail 1.

[0022] Note that the number of raceways 10 and 11 provided in the guide rail 1 and the slider 2 is not limited to two rows on one side, and may be, for example, one row on one side or three or more rows. Further, the cross-sectional shape of the raceways 10 and 11 may be an arc shape formed of a single arc as described above, or may be a substantially V-shaped (Gothic arc-shaped groove) formed by combining two arcs with different centers of curvature.

[0023] Furthermore, the slider 2 is provided with return passages 14A, 14A, 14B, 14B (hereinafter, 14 may be used as a collective reference numeral for these) formed by through holes having a substantially circular cross-sectional shape that penetrate in the longitudinal direction parallel to the rolling passage 13 at the upper and lower portions of the thick-walled portions of the left and right leg portions 6, 6 of the slider body 2A (see FIGS. 2 and 3).

[0024] The end cap 2B is made of, for example, a molded product of a resin material, and has a substantially U-shaped cross-sectional shape similar to that of the slider body 2A. Further, on both left and right sides of the back surface (contact surface with the slider body 2A) of the end cap 2B, direction-changing passages 15 having a circular cross-sectional shape and curved in an arc shape are formed in two upper and lower stages (see FIG. 3). When this end cap 2B is attached to the slider body 2A with a fastening member such as a screw, the rolling passage 13 and the return passage 14 are connected by the direction-changing passage 15. Note that the cross-sectional shape of the direction-changing passage 15 is schematically shown in FIG. 3.

[0025] These return passages 14 and the direction-changing passages 15 at both ends constitute a rolling element conveyance path 16 that conveys and circulates the rolling elements 3 from the end point to the start point of the rolling passage 13, and the rolling passage 13 and the rolling element conveyance path 16 constitute a substantially annular circulation path (see FIG. 3). This substantially annular circulation path is formed in two upper and lower stages on both left and right sides with the guide rail 1 interposed therebetween.

[0026] When the slider 2 moves longitudinally along the guide rail 1, the rolling elements 3 loaded in the rolling path 13 roll within the rolling path 13 and move in the same direction as the slider 2 with respect to the guide rail 1. When the rolling element 3 reaches the end point of the rolling path 13, it is scooped up from the rolling path 13 and sent to the direction-changing path 15. The rolling element 3 that has entered the direction-changing path 15 changes its direction and is introduced into the return path 14, passes through the return path 14, reaches the opposite direction-changing path 15, changes its direction again here, and returns to the starting point of the rolling path 13. By infinitely repeating the circulation of the rolling element 3 within such a circulation path, the slider 2 smoothly moves along the guide rail 1.

[0027] FIG. 4(a) is a perspective view showing a part of the slider body 2A cut away, and FIG. 4(b) is an enlarged perspective view of a part of the leg portion 6 indicated by the chain line in FIG. 4(a). FIG. 5(a) is a view of a part of the leg portion 6 of FIG. 4 seen in the direction of arrow VA. FIG. 5(b) is a view of the track groove 11A seen by cutting the leg portion 6 shown in FIG. 5(a) with a vertical reference plane VP that is orthogonal to the horizontal reference plane HP and passes through the leg portion 6 in the vicinity of both ends in the width direction of the track groove 11A. The vertical reference plane VP is located on the track groove 11A side with respect to the center line O1 of the straight portion of the rolling path 13A (the same applies in the following embodiments). FIG. 5(c) is a view showing a cross section of the end of the track groove 11A cut by the horizontal reference plane HP. FIG. 5(d) is a view showing a cross section of the end of the track groove 11A cut by the vertical reference plane VP, and is shown together with the rotation locus of the cutting tool (or grinding tool).

[0028] Referring to the drawings, the end shapes of the track grooves 11A and 11B will be described. Hereinafter, the track groove 11A will be described as the upper track groove, and the track groove 11B will be described as the lower track groove. Also, when simply referring to the first track surface, it refers to at least one of the first upper track surface and the first lower track surface, and when simply referring to the second track surface, it refers to at least one of the second upper track surface and the second lower track surface.

[0029] In FIGS. 4(a) to 4(b), the upper track groove 11A has a first upper track surface 11Aa on the central side of the slider body 2A and a second upper track surface 11Ab on the end side of the slider body 2A. The first upper track surface 11Aa and the second upper track surface 11Ab are each bounded by a horizontal reference plane HP (see FIG. 5) passing through the groove bottom. The part above the horizontal reference plane HP is called the upper flank, and the part below the horizontal reference plane HP is called the lower flank. The upper flank and the lower flank are symmetric with respect to the horizontal reference plane HP.

[0030] The first upper track surface 11Aa has a uniform cross-section orthogonal to the longitudinal direction. Let the center line of the cylindrical space formed by the first upper track surface 11Aa and the track groove 10A (see FIG. 2) of the guide rail 1 be the center line O1 of the straight part of the rolling passage 13A. The center line O1 of the straight part of the rolling passage 13A is within the horizontal reference plane HP (FIG. 5(a)). In contrast, the second upper track surface 11Ab is formed such that the cross-section orthogonal to the longitudinal direction is partially different.

[0031] In FIG. 5, the second upper track surface 11Ab has a first upward inclined surface 11Ac extending along the center line O1 of the straight part, a second upward inclined surface 11Ad formed above and in contact with the first upward inclined surface 11Ac, and a third upward inclined surface 11Ae formed below and in contact with the first upward inclined surface 11Ac. The second upward inclined surface 11Ad and the third upward inclined surface 11Ae constitute a chamfered portion. The first upward inclined surface 11Ac is symmetric with respect to the horizontal reference plane HP, and the second upward inclined surface 11Ad and the third upward inclined surface 11Ae each have a shape symmetric with respect to the horizontal reference plane HP. Here, when simply referring to the first inclined surface, it refers to at least one of the first upward inclined surface and the first downward inclined surface described later. When simply referring to the second inclined surface, it refers to at least one of the second upward inclined surface and the second downward inclined surface described later. When simply referring to the third inclined surface, it refers to at least one of the third upward inclined surface and the third downward inclined surface described later.

[0032] As shown in Fig. 5(b), the first upward inclined surface 11Ac is connected to the first upper raceway surface 11Aa, while the second upward inclined surface 11Ad and the third upward inclined surface 11Ae are longitudinally spaced apart from the first upper raceway surface 11Aa. Specifically, when viewed in a direction orthogonal to the horizontal reference plane HP of the first upward inclined surface 11Ac, the width is uniform in the vicinity of the first upper raceway surface 11Aa, and is formed in a tapered shape as viewed in the direction of Fig. 5(b) so as to gradually become narrower from the vicinity of the first upper raceway surface 11Aa toward the end of the slider body 2A. On the other hand, the second upward inclined surface 11Ad and the third upward inclined surface 11Ae start from a position at a predetermined distance from the first upper raceway surface 11Aa, and are formed in a substantially triangular shape as viewed in the direction of Fig. 5(b) so that the width when viewed in a direction orthogonal to the horizontal reference plane HP gradually becomes wider toward the end of the slider body 2A.

[0033] The first upward inclined surface 11Ac starts from a position at a distance L1 from the end face (longitudinal end) 2Aa of the slider body 2A (leg portion 6) and ends at the end face 2Aa. The distance L1 is defined as the longitudinal length of the first upward inclined surface 11Ac. When the diameter of the rolling element 3 is Da, it is preferably L1 = 1.0×Da to 2.0×Da.

[0034] As shown in Fig. 5(c), the first upward inclined surface 11Ac has a crowning shape that moves away from the straight portion center line O1 (vertical reference plane VP) of the rolling passage 13A (upward in Fig. 5(c)) as it moves away from the first upper raceway surface 11Aa. The crowning shape is an arc shape with a radius of curvature R1 in the cross section of Fig. 5(c) including the horizontal reference plane HP.

[0035] On the other hand, as shown in FIG. 5(d), the second upward inclined surface 11Ad starts from a position at a distance L2 from the end surface 2Aa of the slider body 2A (leg portion 6) and ends at the end surface 2Aa. When the longitudinal length of the first upward inclined surface 11Ac is L1, it is preferable that L1 > L2. If L2 is longer than L1, the possibility of inhibiting the function of supporting the load of the upper raceway groove 11A and the crowning function of the first upward inclined surface 11Ac increases, and the axial cutting amount of the blank (material) of the slider body 2A during processing also increases. As a result, there is a concern that the lead time increases due to reducing the radial cutting amount and the load on the tool increases. On the contrary, by setting L1 > L2, the axial cutting amount of the blank of the slider body 2A during processing can be suppressed without disturbing the functions of the upper raceway groove 11A and the first upward inclined surface 11Ac.

[0036] The second upward inclined surface 11Ad has a chamfered shape that separates from the horizontal reference plane HP (upward in FIG. 5(d)) as it separates from the first upper raceway surface 11Aa. The chamfered shape is preferably an arc shape with a radius of curvature R2 in the cross section of FIG. 5(d) including the vertical reference plane VP. However, in this embodiment, R2 = ∞, that is, the chamfered shape is a straight line in the cross section of FIG. 5(d).

[0037] In the cross section shown in FIG. 5(d), the intersection point of the first upward inclined surface 11Ac and the second upward inclined surface 11Ad is preferably a discontinuous point. Specifically, taking the cross section shown in FIG. 5(d) as a two-dimensional coordinate system, further representing the surface shape of the first upward inclined surface 11Ac by the curve CL1 and the surface shape of the second upward inclined surface 11Ad by the curve C2, when the intersection point of the first upward inclined surface 11Ac and the second upward inclined surface 11Ad is P1, if the slope (derivative value) of the tangent line of the curve CL1 at the intersection point P1 and the slope (derivative value) of the tangent line of the curve CL2 at the intersection point P1 are different, the curve CL1 and the curve CL2 are discontinuous at the intersection point P1, and at this time, the intersection point P1 is called a discontinuous point. The intersection point P1 is preferably the vertex of the convex portion protruding toward the center line O1 of the straight portion on the second upper raceway surface 11Ab.

[0038] Regarding the shape of the third upward inclined surface 11Ae, since it is the same as the shape of the second upward inclined surface 11Ad except for being symmetric with respect to the horizontal reference plane HP, the description thereof is omitted.

[0039] Also, in FIGS. 4(a) to 4(b), the lower track groove 11B has, in parallel with the upper track groove 11A, a first lower track surface 11Ba on the central side of the slider body 2A and a second lower track surface 11Bb on the end side of the slider body 2A. The first lower track surface 11Ba and the second lower track surface 11Bb are each bounded by the horizontal reference plane HP (see FIG. 2) at the groove bottom. The part above the horizontal reference plane HP is called the upper flank, and the part below the horizontal reference plane HP is called the lower flank. The upper flank and the lower flank are symmetric with respect to the horizontal reference plane HP.

[0040] The first lower track surface 11Ba has a uniform cross-section orthogonal to the longitudinal direction. On the other hand, the second lower track surface 11Bb is formed such that the cross-section orthogonal to the longitudinal direction is partially different.

[0041] The second lower track surface 11Bb has a first downward inclined surface 11Bc extending along the horizontal reference plane HP, a second downward inclined surface 11Bd formed above the first downward inclined surface 11Bc, and a third downward inclined surface 11Be formed below the first downward inclined surface 11Bc. The second downward inclined surface 11Bd and the third downward inclined surface 11Be are symmetric with respect to the horizontal reference plane HP. Since the lower track groove 11B has the same configuration as the upper track groove 11A, the description thereof is omitted. Further, since the shape of the other end side of the upper track groove 11A and the lower track groove 11B is the same as described above, the description thereof is omitted.

[0042] (Operational effects of this embodiment) FIG. 6 is a schematic diagram showing a cross-section similar to FIG. 5(b) according to the comparative example together with rolling elements. FIG. 7 is a schematic diagram showing a cross-section similar to FIG. 5(b) according to this embodiment together with rolling elements, but the center line O1 of the straight portion of the rolling passage 13A is shifted in the direction perpendicular to the paper surface. Here, the rolling passage 13A is taken as an example for explanation, but the same applies to the rolling passage 13B.

[0043] In contrast to this embodiment, the slider body of the comparative example does not have a second raceway surface, and the cylindrical first upper raceway surface 11Aa intersects directly with the end face 2Aa. The configurations of the other comparative examples are the same as those of this embodiment.

[0044] For example, due to the influence of centrifugal force, vibration, etc. when passing through the direction-changing path 15 (see FIG. 3) in the end cap 2B, the center of the rolling element 3 may enter the rolling path 13A from the direction-changing path 15 in a state where it is displaced with respect to the center line O1 of the straight portion of the rolling path 13A. At this time, the amount of displacement between the center of the rolling element 3 and the center line O1 of the straight portion of the rolling path 13A is defined as the eccentricity e. Since the diameter of the rolling element 3 is slightly smaller than the diameter of the rolling path 13A, when the eccentricity e is smaller than 1 / 2 of the diameter difference (diameter of the rolling path 13A - diameter of the rolling element 3), the rolling element 3 can smoothly enter the rolling path 13A. However, when the eccentricity e exceeds 1 / 2 of the diameter difference, the rolling element 3 may abut against the edge at the entry direction end of the rolling path 13A, which may cause noise generation and damage to the rolling element 3.

[0045] In contrast, according to this embodiment, the first upper inclined surface 11Ac having a crowning shape is formed at the entry direction end of the rolling path 13A. Therefore, even in a state where the eccentricity exceeds 1 / 2 of the above diameter difference in the horizontal direction, the rolling element 3 that has entered from the direction-changing path 15 obliquely abuts against the convex first upper inclined surface 11Ac having a curvature radius R1 (see FIG. 5(c)) and then rolls and is guided to the first upper raceway surface 11Aa. By suppressing a large change in Hertz stress, noise generation and damage to the rolling element 3 can be suppressed, and smooth movement of the rolling element 3 can be ensured.

[0046] On the other hand, as shown in FIG. 7, there may be a case where the rolling element 3 eccentric with an eccentricity e exceeding 1 / 2 of the diameter difference in the vertical direction enters. In such a case, smooth entry of the rolling element 3 may be inhibited only by the first upper inclined surface 11Ac. In contrast, in the present embodiment, in the vicinity of the entry direction end of the second upper raceway surface 11Ab, above and below the first upper inclined surface 11Ac, a chamfered portion having a drop amount d2, i.e., the second upper inclined surface 11Ad and the third upper inclined surface 11Ae, are formed.

[0047] Therefore, even when the rolling element 3 eccentric with a relatively large eccentricity e in the vertical direction enters, it obliquely contacts the second upper inclined surface 11Ad or the third upper inclined surface 11Ae having a convex shape with a radius of curvature R2 and then rolls, and thereafter is guided from the first upper inclined surface 11Ac to the first upper raceway surface 11Aa. Thereby, the impact force on the slider body 2A can be alleviated, generation of noise and damage to the rolling element 3 can be suppressed, and smooth movement of the rolling element 3 can be ensured.

[0048] Since the lower raceway groove 11B has the same configuration as the upper raceway groove 11A, it exhibits the same effect.

[0049] (Processing method of the first upper raceway surface and the second upper raceway surface) Next, the processing method of the first upper raceway surface 11Aa will be described. When grinding the first upper raceway surface 11Aa, first, in the blank of the slider body 2A, a groove similar to the first upper raceway surface 11Aa is formed by cutting or the like. Thereafter, using a grinding tool that rotates around the center line O1 of the straight portion of the rolling passage 13A, the central portion and the end portion of the upper raceway groove 11A are ground. Thereby, the first upper raceway surface 11Aa and the first upper inclined surface 11Ac are formed.

[0050] After forming the first upper raceway surface 11Aa and the first upper inclined surface 11Ac, chamfering is performed using another cutting tool (or grinding tool) TL to form the second upper inclined surface 11Ad and the third upper inclined surface 11Ae. The cutting tool TL has a conical (tapered) rotational locus as shown by the chain lines in FIGS. 5(a) and 5(d). The maximum diameter of the rotational locus is larger than the vertical width of the first upper raceway surface 11Aa.

[0051] Specifically, as shown in Fig. 5(a), within the horizontal reference plane HP, a machining axis O2 is set that is translated parallel to be separated from the upper track groove 11A with respect to the center line O1 of the straight portion of the rolling passage 13A. Then, while rotating the cutting tool TL around the machining axis O2, the cutting tool TL is brought close to the first upward inclined surface 11Ac along the machining axis O2, and grinding is performed to cut off a part (the upper and lower ends) thereof. Thereby, the second upward inclined surface 11Ad is ground, and at the same time, the third upward inclined surface 11Ae is ground.

[0052] That is, the surfaces of the second upward inclined surface 11Ad and the third upward inclined surface 11Ae, which are chamfered portions, are on a circular locus centered on a point (machining axis) O2 that is shifted along the horizontal reference plane HP so as to be separated from the first upper track surface 11A with respect to the groove bottom center (straight portion center line O1) of the first upper track surface 11A in a cross-section orthogonal to the straight portion center line O1 (a cross-section parallel to Fig. 5(a)). The minimum radius of the circular locus (the distance from the point O2 to the points P4 and P5 on the second upward inclined surface 11Ad and the third upward inclined surface 11Ae that are closest to the point O2) is larger than the groove bottom radius r of the first upper track surface 11A. Here, the edges EG1 and EG2 of the second upward inclined surface 11Ad and the third upward inclined surface 11Ae that intersect the end face 2Aa of the slider body 2A are part of a circle centered on the point O2.

[0053] Similar to the upper track groove 11A, the lower track groove 11B can be machined and formed.

[0054] According to the present embodiment, since the machining of the chamfered portion can be performed only by bringing the cutting tool TL close to the second upper track surface 11Ab along the machining axis O2, the machining time is shortened, and the yield of the slider body 2A can be improved. Further, since the machining of the chamfered portion is performed by cutting off a part of the groove of the second upper track surface 11Ab, the wear of the cutting tool TL is also small, the maintenance interval is lengthened, and the cost of the slider body 2A can be reduced.

[0055] Furthermore, in the present embodiment, at the end of the raceway groove of the slider body 2A, in addition to crowning, chamfered portions are provided above and below the end of the raceway groove where the rolling elements 3 are likely to collide, thereby dulling the edge portion, reducing the contact surface pressure during edge collision, and suppressing premature wear of the rolling elements 3. Also, by leaving the groove bottom in the crowning state, the load zone that supports the load remains unchanged, and the durability and operability are maintained. From the above, it is possible to propose a linear guide device capable of achieving a longer life while maintaining durability.

[0056] That is, according to the present embodiment, by forming the crowning shape and the chamfered portion in the raceway grooves 11, 11B of the slider body 2A in a composite manner, even when the rolling elements 3 enter eccentrically into the rolling passages 13A, 13B, smooth movement can be ensured. Also, since it is possible to suppress the rolling elements 3 from colliding with the edges at the ends of the rolling passages 13A, 13B, it is possible to suppress an increase in the collision pressure when the rolling elements 3 enter the rolling passages 13A, 13B.

[0057] (Second Embodiment) FIG. 8(a) is a view similar to FIG. 5(a) in the second embodiment. FIG. 8(b) is a view of the upper raceway groove 11A seen by cutting the leg portion 6 shown in FIG. 8(a) with a vertical reference plane VP that is orthogonal to the horizontal reference plane HP and passes through the leg portion 6 in the vicinity of both ends in the width direction of the upper raceway groove 11A. FIG. 8(c) is a view showing a cross section of the end of the upper raceway groove 11A cut by the horizontal reference plane HP. FIG. 8(d) is a view showing a cross section of the end of the upper raceway groove 11A cut by the vertical reference plane VP.

[0058] In the present embodiment, compared with the first embodiment, the shapes of the second upper inclined surface 11Ad and the third upper inclined surface 11Ae of the upper raceway groove 11A are different, and accordingly, the shape of the first upper inclined surface 11Ac is also different. The same applies to the lower raceway groove 11B. Since the other configurations are the same as those in the first embodiment, duplicate explanations are omitted.

[0059] The first upward inclined surface 11Ac has a crowning shape that moves away from the center line O1 (vertical reference plane VP) of the straight portion of the rolling path 13A (upward in FIG. 8(c)) as it moves away from the first upper track surface 11Aa. The crowning shape is an arc shape with a radius of curvature R1 in the cross-section of FIG. 8(c) including the horizontal reference plane HP.

[0060] As shown in FIG. 8(d), the second upward inclined surface 11Ad starts at a position at a distance L2 from the end face 2Aa of the slider body 2A (leg portion 6) and ends at the end face 2Aa. When the longitudinal length of the first upward inclined surface 11Ac is L1, L1 > L2.

[0061] The second upward inclined surface 11Ad has a chamfered shape that moves away from the horizontal reference plane HP (upward in FIG. 8(d)) as it moves away from the first upper track surface 11Aa. The chamfered shape is preferably an arc shape with a radius of curvature R2 in the cross-section of FIG. 8(d) including the vertical reference plane VP. However, in this embodiment, unlike the first embodiment, R2 ≠ ∞ and it has an inward convex shape.

[0062] In the cross-section shown in FIG. 8(d), the intersection point P1 where the first upward inclined surface 11Ac and the second upward inclined surface 11Ad intersect is preferably a discontinuous point.

[0063] The first upper track surface 11Aa and the second upper track surface 11Ab are formed in the same manner as in the first embodiment. Then, using a cutting tool TL, chamfering is performed to machine and form the second upward inclined surface 11Ad and the third upward inclined surface 11Ae. The machining tool TL has a rotational locus with an outer circumference in an arc shape (for example, a tapered shape such as a toroidal shape) as shown by the dashed lines in FIGS. 8(a) and 8(d). The maximum diameter of the rotational locus is larger than the vertical width of the first upper track surface 11Aa.

[0064] Further, the surfaces of the second upwardly inclined surface 11Ad and the third upwardly inclined surface 11Ae, which are chamfered portions, are on a rotational locus centered at a point O2 shifted along a horizontal reference plane HP so as to be separated from the first upper raceway surface 11A with respect to the groove bottom center (linear portion center line O1) of the first upper raceway surface 11A in a cross section orthogonal to the linear portion center line O1 (a cross section parallel to FIG. 8(a)). The minimum radius of the rotational locus (the distance from the point O2 to the points P4 and P5 on the second upwardly inclined surface 11Ad and the third upwardly inclined surface 11Ae closest to the point O2) is larger than the groove bottom radius r of the first upper raceway surface 11A. Here, the edges EG1 and EG2 of the second upwardly inclined surface 11Ad and the third upwardly inclined surface 11Ae that intersect the end face 2Aa of the slider body 2A are part of a circle centered at the point O2.

[0065] Specifically, as shown in FIG. 8(a), a machining axis O2 is set within the horizontal reference plane HP and translated in parallel so as to be separated from the upper raceway groove 11A with respect to the linear portion center line O1 of the rolling passage 13A. Then, while rotating the cutting tool TL around the machining axis O2, the cutting tool TL is brought close to the second upper raceway surface 11Ab along the machining axis O2, and grinding is performed so as to cut a part thereof. Thereby, the second upwardly inclined surface 11Ad is ground, and at the same time, the third upwardly inclined surface 11Ae is ground.

[0066] Similar to the upper raceway groove 11A, the lower raceway groove 11B can be machined and formed.

[0067] According to the present embodiment, since the cross-sectional shapes of the second upwardly inclined surface 11Ad and the third upwardly inclined surface 11Ae and the like are arc-shaped, the sharpness of the edge portion (intersection point P1) is suppressed, and the chamfered portion is gently curved, so that the contact surface pressure is reduced and the clogging of the rolling elements 3 is further reduced, and there is an effect of suppressing early wear and improving operability.

[0068] (Third Embodiment) FIG. 9(a) is a view similar to FIG. 5(a) in the third embodiment. FIG. 9(b) is a view of the upper track groove 11A seen by cutting the leg portion 6 shown in FIG. 9(a) with a vertical reference plane VP that is orthogonal to the horizontal reference plane HP and passes through the leg portion 6 in the vicinity of both ends in the width direction of the upper track groove 11A. FIG. 9(c) is a view showing a cross section of the end portion of the upper track groove 11A cut by the horizontal reference plane HP. FIG. 9(d) is a view showing an upper cross section of the end portion of the upper track groove 11A cut by the vertical reference plane VP.

[0069] In the present embodiment, with respect to the first embodiment, the second upwardly inclined surface 11Ad and the third upwardly inclined surface 11Ae of the upper track groove 11A are connected on the end face 2Aa side, and accordingly, the shape of the first upwardly inclined surface 11Ac is also different. The same applies to the lower track groove 11B. Since the other configurations are the same as those in the first embodiment, duplicate explanations are omitted.

[0070] Above the horizontal reference plane HP, the second upper track surface 11Ab has a first upwardly inclined surface 11Ac and a second upwardly inclined surface 11Ad. The first upwardly inclined surface 11Ac has a crowning shape that moves away from the center line O1 (vertical reference plane VP) of the straight portion of the rolling passage 13A (upward in FIG. 9(c)) as it moves away from the first upper track surface 11Aa, but ends before reaching the end face 2Aa. The crowning shape is an arc shape with a radius of curvature R1 in the cross section of FIG. 9(c) including the horizontal reference plane HP.

[0071] As shown in FIG. 9(d), the second upwardly inclined surface 11Ad starts from a position at a distance L2 from the end face 2Aa of the slider body 2A (leg portion 6) and ends at the end face 2Aa. When the longitudinal length of the first upwardly inclined surface 11Ac is L1, L1 > L2.

[0072] The second upwardly inclined surface 11Ad has a chamfered shape that moves away from the horizontal reference plane HP (upward in FIG. 9(d)) as it moves away from the first upper track surface 11Aa. The chamfered shape is preferably an arc shape with a radius of curvature R2 in the cross section of FIG. 9(d) including the vertical reference plane VP. In the present embodiment, R2 = ∞ may be used, or R2 < R1 may be used.

[0073] Below the horizontal reference plane HP, the inner surface of the upper raceway groove 11A is a part of a cylindrical surface. Therefore, using the cutting tool TL of the above-described embodiment, only the second upward inclined surface 11Ad can be formed as a chamfering process. The lower raceway groove 11B can be formed in the same manner.

[0074] That is, the surfaces of the second upward inclined surface 11Ad and the third upward inclined surface 11Ae, which are chamfered portions, are on a rotation locus centered at a point O2 shifted along the horizontal reference plane HP so as to be separated from the first upper raceway surface 11A with respect to the groove bottom center (linear portion center line O1) of the first upper raceway surface 11A in a cross section orthogonal to the linear portion center line O1 (a cross section parallel to FIG. 9(a)). The minimum radius of the rotation locus (the distance from the point O2 to the points P4 and P5 on the second upward inclined surface 11Ad and the third upward inclined surface 11Ae closest to the point O2) is larger than the groove bottom radius r of the first upper raceway surface 11A. Here, the edges EG3 of the second upward inclined surface 11Ad and the third upward inclined surface 11Ae that intersect the end face 2Aa of the slider body 2A are connected and form a part of a circle centered at the point O2. The second upward inclined surface 11Ad and the third upward inclined surface 11Ae of the present embodiment can be formed by machining by adjusting the depth of cut along the machining axis O2 using the above-described cutting tool.

[0075] As shown in FIG. 9(b), since the second upward inclined surface 11Ad and the third upward inclined surface 11Ae, which are two chamfered portions, are integrated near the groove bottom, the edge portion of the groove bottom can be removed while maintaining the crowning, and thus there is an effect of suppressing early wear while maintaining the durability and operability.

[0076] (Fourth Embodiment) FIG. 10(a) is a view similar to FIG. 5(a) in the fourth embodiment. FIG. 10(b) is a view of the upper raceway groove 11A seen by cutting the leg portion 6 shown in FIG. 10(a) with a vertical reference plane VP that is orthogonal to the horizontal reference plane HP and passes through the leg portion 6 in the vicinity of both ends in the width direction of the upper raceway groove 11A. FIG. 10(c) is a view showing an upper cross section of an end portion of the upper raceway groove 11A cut by an inclined plane SP that includes the linear portion center line O1 of the rolling passage 13A and is inclined with respect to the horizontal reference plane HP. FIG. 10(d) is a view showing a cross section of an end portion of the upper raceway groove 11A cut by the vertical reference plane VP.

[0077] In this embodiment, compared with the first embodiment, the shape of the upper track groove 11A is different above and below the horizontal reference plane HP. The same applies to the lower track groove 11B. Since the other configurations are the same as those in the first embodiment, duplicate descriptions are omitted.

[0078] The second upper track surface 11Ab has a first upper inclined surface 11Ac and a second upper inclined surface 11Ad. The first upper inclined surface 11Ac has a crowning shape that moves away from the center line O1 (vertical reference plane VP) of the straight portion of the rolling path 13A (upward in FIG. 10(c)) as it moves away from the first upper track surface 11Aa, but ends before reaching the end face 2Aa. The crowning shape is an arc shape with a radius of curvature R1 in the cross-section of FIG. 10(c) including the horizontal reference plane HP.

[0079] As shown in FIG. 10(d), the second upper inclined surface 11Ad starts from a position at a distance L2 from the end face 2Aa of the slider body 2A (leg portion 6) and ends at the end face 2Aa. When the longitudinal length of the first upper inclined surface 11Ac is L1, L1 > L2.

[0080] The second upper inclined surface 11Ad has a chamfered shape that moves away from the horizontal reference plane HP and the vertical reference plane VP (upward in FIG. 10(d)) as it moves away from the first upper track surface 11Aa. The chamfered shape is preferably an arc shape with a radius of curvature R2 in the cross-section of FIG. 10(d) including the inclined surface SP. In this embodiment, R2 = ∞ may be used, or R2 < R1 may be used.

[0081] In the cross-section shown in FIG. 10(d), the intersection point P1 where the first upper inclined surface 11Ac and the second upper inclined surface 11Ad intersect is preferably a discontinuous point.

[0082] That is, the surface of the second upward inclined surface 11Ad which is the chamfered portion is on a rotation locus centered at point O2 that is shifted along the horizontal reference plane HP so as to be separated from the first upper raceway surface 11A with respect to the groove bottom center (linear portion center line O1) of the first upper raceway surface 11A in a cross section orthogonal to the linear portion center line O1 (a cross section parallel to FIG. 10(a)), and the minimum radius of the rotation locus (the distance from point O2 to point P4 on the second upward inclined surface 11Ad closest to point O2) is larger than the groove bottom radius r of the first upper raceway surface 11A. Here, the edge EG1 of the second upward inclined surface 11Ad that intersects the end surface 2Aa of the slider body 2A is a part of a circle centered at point O2. Instead of omitting the second upward inclined surface 11Ad, a third upward inclined surface 11Ae may be provided.

[0083] As in this embodiment, when the cross-sectional shape of the upper raceway groove 11A etc. is not limited to a semi-circular shape and it is necessary to consider the contact angle between the rolling element 3 and the upper raceway groove 11A etc., or when the chamfered portion is limited to a portion where the rolling element 3 is likely to collide, there is the same effect as the above-described embodiment.

[0084] (Fifth Embodiment) FIG. 11(a) is a view similar to FIG. 5(a) in the fifth embodiment. FIG. 11(b) is a view of the upper raceway groove 11A seen by cutting the leg portion 6 shown in FIG. 11(a) with a vertical reference plane VP that is orthogonal to the horizontal reference plane HP and passes through the leg portion 6 in the vicinity of both ends in the width direction of the upper raceway groove 11A. FIG. 11(c) is a view showing a cross section of the end portion of the upper raceway groove 11A cut by the horizontal reference plane HP. FIG. 11(d) is a view showing a cross section of the end portion of the upper raceway groove 11A cut by the vertical reference plane VP.

[0085] The shape of the upper raceway groove 11A in this embodiment is the same as that in the first embodiment, but the surface roughness of the second upper inclined surface 11Ad and the third upper inclined surface 11Ae is rougher than that of the first upper inclined surface 11Ac. The surface roughness of the first upper inclined surface 11Ac is substantially equal to the surface roughness of the first upper raceway surface 11Aa. The surface roughness can be evaluated by the arithmetic mean roughness Ra or the like. For example, it is preferable that the arithmetic mean roughness Ra of the second upper inclined surface 11Ad and the third upper inclined surface 11Ae is 50% or more rougher than the arithmetic mean roughness Ra of the first upper inclined surface 11Ac. The same applies to the lower raceway groove 11B. Since the other configurations are the same as those in the first embodiment, redundant descriptions are omitted.

[0086] For example, the surface roughness of the second upper inclined surface 11Ad and the third upper inclined surface 11Ae can be made rougher than that of the first upper inclined surface 11Ac by chamfering with a grinding tool having a large grain size of abrasive grains or forming tool marks on the chamfered portion using a cutting tool. By making the surface roughness of the second upper inclined surface 11Ad and the third upper inclined surface 11Ae rougher, the adhesion of the lubricant to the chamfered portion is promoted, and an effect of suppressing damage when the rolling element 3 collides with the chamfered portion can be expected.

[0087] The present invention is not limited to the above embodiments. Combinations of the respective configurations of the embodiments, as well as modifications and applications made by those skilled in the art based on the description in the specification and well-known techniques, are also within the scope contemplated by the present invention and are included in the scope for which protection is sought.

Explanation of Reference Numerals

[0088] 1 Guide rail 2 Slider 2A Slider body 2B End cap 3 Rolling element 4 Retainer 10A, 10B Raceway groove 11A, 11A Raceway groove 13A, 13B Rolling passage 14A, 14B Return passage 15 Direction-changing path

Claims

1. A guide rail, a slider arranged to move relative to the guide rail in the longitudinal direction, a linear guide device comprising a plurality of rolling elements arranged to roll freely along a rolling passage formed between the guide rail and the slider, wherein the slider comprises a slider body having a raceway groove arranged opposite to the raceway groove of the guide rail to form a rolling passage for the rolling elements, and a return passage for the rolling elements, and an end cap having a direction-changing passage connecting the return passage and the rolling passage, the raceway groove of the slider body has a first raceway surface on the central portion side of the rolling passage and a second raceway surface on the end portion side of the rolling passage, the second raceway surface has a first inclined surface extending from the first raceway surface to the end surface of the slider body, and a chamfered portion extending to the end surface of the slider body without contacting the first inclined surface, when a plane passing through the center in the width direction of the slider body and the longitudinal axis of the guide rail is defined as a vertical center plane CP, a plane perpendicular to the vertical center plane CP and passing through the center line of the straight portion of the rolling passage is defined as a horizontal reference plane HP, and a plane parallel to the vertical center plane CP and intersecting the chamfered portion is defined as a vertical reference plane VP, the surface of the chamfered portion is on a circular locus centered at a point O2 shifted along the horizontal reference plane HP so as to be separated from the first raceway surface with respect to the center line O1 of the straight portion of the rolling passage in a cross section perpendicular to the center line of the straight portion, and the minimum radius of the circular locus is larger than the groove bottom radius r of the first raceway surface, a linear guide device characterized by the above.

2. The edge of the chamfered portion farthest from the point O2 is a part of a circle centered at the point O2, the linear guide device according to claim 1, characterized by the above.

3. The first inclined surface is separated from the vertical reference plane VP as it approaches the end surface of the slider body, the surface of the chamfered portion is separated from the horizontal reference plane HP as it approaches the end surface of the slider body, the linear guide device according to claim 2, characterized by the above.

4. The cross-sectional shape of the first inclined surface obtained by cutting with the horizontal reference plane HP has an arc shape with a radius of curvature R1, the surface cross-sectional shape of the chamfered portion obtained by cutting with the vertical reference plane VP has an arc shape with a radius of curvature R2, and R2 < R1, the linear guide device according to claim 3, characterized by the above.

5. The cross-sectional shape of the first inclined surface obtained by cutting along the horizontal reference plane HP has an arc shape, and the intersection of the surface of the chamfered portion intersecting the vertical reference plane VP is linear. The linear motion guide device according to claim 3, characterized in that.

6. A second inclined surface and a third inclined surface are formed on both sides of the first inclined surface with the horizontal reference plane interposed therebetween. The second inclined surface and the third inclined surface are the chamfered portions. The linear motion guide device according to claim 1, characterized in that.

7. The second inclined surface and the third inclined surface are connected. The linear motion guide device according to claim 6, characterized in that.

8. A second inclined surface is formed on the side spaced apart from the first inclined surface across the horizontal reference plane. The second inclined surface is the chamfered portion. The linear motion guide device according to claim 1, characterized in that.

9. The surface roughness of the surface of the chamfered portion is different from the surface roughness of the first inclined surface. The linear motion guide device according to claim 1, characterized in that.

10. A guide rail, A slider arranged to move relative to the guide rail in the longitudinal direction, A method for manufacturing a linear motion guide device including a plurality of rolling elements arranged to be freely rollable along a rolling passage formed between the guide rail and the slider, The slider is A slider body having a raceway groove facing the raceway groove of the guide rail to form a rolling passage for the rolling elements and a return passage for the rolling elements, An end cap having a direction-changing passage connecting the return passage and the rolling passage, The raceway groove of the slider body has a first raceway surface on the central portion side of the rolling passage and a second raceway surface on the end portion side of the rolling passage, The second raceway surface has a first inclined surface extending from the first raceway surface to the end face of the slider body and a chamfered portion extending to the end face of the slider body without contacting the first inclined surface. A grinding tool or a cutting tool having a tapered rotation locus is rotated around a machining axis O2 while being translated parallel to the straight-line portion center line O1 of the rolling passage so as to be separated from the first raceway surface, and is brought close to the second raceway surface along the machining axis O2, and a part of the first inclined surface is cut off to form the chamfered portion. A method for manufacturing a linear motion guide device, characterized in that.

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