阅读说明：本技术 直动引导单元及其制造方法 (Linear motion guide unit and method for manufacturing same ) 是由 大石真司 鹤田健一郎 于 2020-01-17 设计创作，主要内容包括：本发明涉及一种直动引导单元及其制造方法,在该直动引导单元中,通过至少一枚金属板成形加工滑动件,可降低制造成本,降低转动体的滑动阻力。该直动引导单元由轨道导轨以及由一枚金属板成形加工而成的滑动件构成。轨道导轨具有底部以及在底部的两侧相对且沿长度方向延伸而直立设置的一对的侧部,在侧部形成有供转动体转动的轨道槽。由一枚金属板构成的滑动件具有：上部；一对袖部,在其两侧相对且形成有轨道槽和返回路径；以及端盖部,形成于上部的两端面且形成有方向转换路径。(The present invention relates to a linear motion guide unit in which a sliding member is formed by at least one metal plate, thereby reducing manufacturing cost and reducing sliding resistance of a rotating body, and a method for manufacturing the same. The linear guide unit is composed of a track rail and a slider formed by forming a metal plate. The track guide rail has a bottom portion and a pair of side portions which are opposite to each other on both sides of the bottom portion and are vertically arranged to extend in a longitudinal direction, and a track groove in which the rotating body is rotated is formed in the side portions. A slider composed of one metal plate has: an upper portion; a pair of sleeve portions opposed to each other at both sides thereof and having a track groove and a return path formed thereon; and end caps formed on both end surfaces of the upper portion and having direction change paths formed thereon.)

1. A linear motion guide unit, wherein,

comprises a rail guide rail having a U-shaped cross section and a slider disposed on the rail guide rail via a plurality of rolling bodies so as to be relatively slidable, the slider being formed of one metal plate,

the track guide rail is composed of a bottom part and a pair of side parts, the side parts are opposite to each other at two sides of the bottom part and are vertically arranged in an extending way along the length direction, first track grooves for the rotating bodies to respectively rotate are formed,

the slide is composed of an upper portion, a pair of sleeve portions facing each other on both sides of the upper portion and extending and hanging down in a longitudinal direction, and a pair of end cap portions hanging down from the upper portion and located on both end faces of the upper portion and the sleeve portions, respectively,

a second track groove extending along the first track groove and a return path extending in parallel with the second track groove are formed in the sleeve, the first track groove and the second track groove together form a track path, arc-shaped direction changing paths communicating the track path and the return path are formed in the end cap portions, respectively, and the rolling element rolls in a circulation path formed by the track path, the return path, and a pair of the direction changing paths.

2. The linear motion guide unit as recited in claim 1,

the second track groove is formed on the base portion side of the sleeve portion and is curved inward in a semi-cylindrical shape, and the return path is formed on the distal end portion side of the sleeve portion and is curved in a cylindrical shape.

3. The linear motion guide unit as recited in claim 2,

an opening formed in the cylindrical longitudinal end surface forming the return path is smaller than a diameter of a ball serving as the rolling element and is located more inward than the second track groove of the sleeve portion.

4. The linear motion guide unit as recited in claim 1,

the end cap portion is formed to hang down from an end surface of the upper portion, and the direction change paths are formed to cover both ends of the sleeve portion, respectively, and to communicate the return path with the track path.

5. The linear motion guide unit as recited in claim 1,

a projection portion that holds up the rotating body from the track path toward the direction change path is formed at a front end of the direction change path on the track path side, and the projection portion is formed so as to be able to project in an R shape in the first track groove of the track rail.

6. The linear motion guide unit as recited in claim 1,

at least the metal plates forming the sliding member have substantially the same plate thickness.

7. The linear motion guide unit as recited in claim 1,

a mounting screw hole for mounting an object member is formed in the upper portion of the slider, the mounting screw hole is formed in an inner peripheral surface of a cylindrical boss portion in which a part of the upper portion protrudes to a back surface side, and a mounting hole for mounting the rail guide to a base is formed in the bottom portion of the rail guide.

8. A method of manufacturing a linear guide unit, wherein,

the sliding member mechanism in the linear guide unit according to any one of claims 1 to 7 is produced by the following process: a notch portion for bending the metal plate is formed between a sleeve portion forming the sleeve portion and an end cap portion forming the end cap portion in the metal plate, and the sleeve portion and the end cap portion are respectively subjected to bending processing by press forming with respect to an upper portion forming portion.

9. The manufacturing method of the linear motion guide unit according to claim 8,

at least one of the rail guide and the slider is subjected to a surface hardening treatment.

Technical Field

The present invention relates to a linear guide unit having a slider that is movable relative to a rail in a longitudinal direction, and a method for manufacturing the same, and is applied to, for example, a drawer of furniture, a toy, or the like, a slide portion of a wheelchair lifting device of a welfare vehicle, or the like.

Background

Conventionally, as a linear guide device, a rolling guide device is known which is configured by a track rail having a U-shaped cross section and a slide member slidably disposed on the track rail via a plurality of rolling bodies. In the rolling guide device, the sliding member is formed in a channel shape having a pair of flange portions formed by bending a metal plate member and positioned on the lateral net and the lateral side surfaces of the lateral net in the width direction. Each flange portion is formed with a track groove for circulation of balls. The track groove is composed of the following components: a load linear groove for loading and rolling the ball; a pair of ball deflection grooves for releasing the load from the balls rolling in the load straight grooves and converting the direction; and a non-load-bearing linear groove for conveying the balls from one of the ball deflection grooves to the other of the ball deflection grooves. Further, the rolling guide device is configured such that the unloaded linear groove and the deflecting groove are formed to face the track rail so that the rolling element does not fall out of the unloaded linear groove and the deflecting groove, and the rolling element in an unloaded state is moved in sliding contact with the track rail (see, for example, WO 2007/004488).

Disclosure of Invention

However, in the rolling guide device disclosed in WO2007/004488, the slide member includes: the track path for rolling away the rotor loaded with load is a load straight line groove; a circulation path along which the rotor having released the load rolls, that is, a no-load linear groove; the rolling direction of the rolling body is changed from one linear groove to the other linear groove. These grooves are formed all on a pair of flange portions positioned on the lateral side of the transverse net and configured to endlessly circulate the rolling element. The rolling guide device is disclosed to form a sliding member from a single metal plate in order to reduce the number of parts and to manufacture the sliding member easily and inexpensively. Specifically, a metal plate is bent into a U-shaped cross section to form flange portions facing the track grooves of the track rail, and the flange portions are recessed by cutting, press forming, coining, or the like to form an endless circular path in an elliptical track shape by the loaded linear grooves, the unloaded linear grooves, and the deflection grooves. In order to prevent the rolling element from falling from the unloaded linear groove and the deflection groove, the unloaded linear groove and the deflection groove are formed to face the track rail, and the rolling element in an unloaded state is moved while being in sliding contact with the track rail. However, in the above-described rolling guide device, since a structure for supporting the rolling body from the load linear groove toward the deflecting groove is not provided, the rolling of the rolling body at the boundary between the load linear groove and the deflecting groove may be unstable, and the sliding member may be difficult to smoothly slide.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a linear guide unit and a method for manufacturing the same, the linear motion guide unit is provided with a slider formed by forming one metal plate, and is capable of forming a track rail by forming one metal plate in the same manner, in particular, it is not necessary to form a track groove, a recess, or the like for reducing the thickness of the slider by cutting, the slider is formed by press working or deep drawing and is formed by an upper portion having a mounting screw hole, a sleeve portion having a track groove and a return path, and an end cap portion having a direction change path, whereby the slider can smoothly roll away from a track path formed by the track groove of the slider and the track groove of the track rail toward a rolling element of the direction change path without increasing the sliding resistance of the rolling element in a circulation path formed by the track groove, the return path, and a pair of direction change paths.

The present invention relates to a linear motion guide unit, wherein,

comprises a rail guide rail having a U-shaped cross section and a slider formed of one metal plate disposed on the rail guide rail via a plurality of rolling bodies so as to be capable of sliding relative to each other,

the track guide rail is composed of a bottom part and a pair of side parts, the side parts are opposite to each other at two sides of the bottom part, extend vertically along the length direction and are provided with first track grooves for the rotating bodies to rotate respectively,

the slider is composed of an upper portion, a pair of sleeve portions which are opposed to each other on both sides of the upper portion and which extend and hang in a longitudinal direction, and a pair of end cap portions which hang from the upper portion and are respectively positioned on both end surfaces of the upper portion and the sleeve portions,

a second track groove extending along the first track groove and a return path extending in parallel with the second track groove are formed in the sleeve, the first track groove and the second track groove together form a track path, and arc-shaped direction changing paths communicating the track path and the return path are formed in the end cap portions, respectively,

the rotating body rolls in a circulating path constituted by the track path, the return path, and the pair of direction changing paths.

In the linear motion guide unit, the second track groove is formed on the base portion side of the sleeve portion so as to be curved inward in a semi-cylindrical shape, and the return path is formed on the distal end portion side of the sleeve portion so as to be curved in a cylindrical shape.

Further, an opening formed in the cylindrical longitudinal end surface forming the return path is smaller than a diameter of a ball serving as the rolling element and is located inside the second track groove of the sleeve portion.

The end cap portion is formed to hang down from an end surface of the upper portion, and covers both ends of the sleeve portion to form the direction change path that communicates the return path with the track path.

In the linear guide unit, a projection portion that supports the rotating body from the track path toward the direction change path is formed at a front end of the direction change path on the track path side, and the projection portion is formed so as to be able to project in an R shape in the first track groove of the track rail.

In the linear guide unit, at least the metal plates forming the slider have substantially the same plate thickness.

In the linear guide unit, a mounting screw hole for mounting an object member is formed in the upper portion of the slider, the mounting screw hole is formed in an inner peripheral surface of a cylindrical boss portion in which a part of the upper portion protrudes to a back surface side, and a mounting hole for mounting the rail guide to a base is formed in the bottom portion of the rail guide.

Further, the present invention relates to a method of manufacturing a linear motion guide unit, wherein,

the slider in the linear guide unit as described above is processed by the steps of: a notch portion for bending the metal plate is formed between a sleeve portion forming the sleeve portion and an end cap portion forming the end cap portion in the metal plate, and the sleeve portion and the end cap portion are respectively subjected to bending processing by press forming with respect to an upper portion forming portion.

In the method of manufacturing the linear guide unit, at least one of the rail guide and the slider is subjected to a surface hardening treatment.

As described above, the linear guide unit according to the present invention is constituted by the slider formed by simply forming one metal plate by press working, and the rail guide having a U-shaped cross section. The rail guide is composed of a bottom portion and a pair of side portions provided upright from opposite sides of the bottom portion. The slider is disposed on the rail guide rail so as to be slidable via the plurality of rolling bodies. A first track groove for rotating the rotating body is formed on each side of the track guide rail, a second track groove opposite to the first track groove and a return path parallel to the second track groove are formed on the sleeve part forming the slider, and a direction switching path for communicating the return path with the track path formed by the first track groove and the second track groove is formed on the end cover part forming the slider. The track path is formed such that the rotor loaded with a load rolls away, and the return path and the direction change path roll away the rotor unloaded with no load. The rotating body endlessly circulates in a circulation path constituted by a track path, a return path, and a pair of direction changing paths. The linear guide unit of the present invention uses a slider formed by bending a steel plate, and can be formed at a lower cost and a lower rigidity than a slider formed by cutting a conventional block-shaped metal block, and can be used for a sliding portion of a drawer, for example.

In the method of manufacturing the linear guide unit, the track groove, the return path, and the direction change path are formed by bending only one metal plate, and therefore, the slider can be formed to have substantially the same plate thickness without being depressed. Further, since the return path along which the unloaded rolling element rolls is formed in a cylindrical shape and the direction change path is formed in an arc shape, and the rolling element passes through these paths, the rolling element can be held in the circulation path between the return path and the direction change path. That is, the rotating body that rolls on the no-load path can be held only by the slider, and the sliding resistance for holding the rotating body can be suppressed because the rotating body is not held by being brought into contact with another member. Further, since the projection portion for supporting the rotating body facing the direction change path from the track path is provided so as to project from the track path, the projection portion can be positioned at a deep position of the track path, and the rotating body facing the direction change path from the track path can be smoothly supported and rolled. Further, since the slider is configured by pressing and bending the sleeve portion formed with the second track groove and the circulation path and the end cap portion formed with the direction change path to the bottom portion of the track rail, by providing the cutout portion in the base portion of at least one of the sleeve portion and the end cap portion, the influence of the bending of the sleeve portion or the end cap portion can be made less likely to be transmitted to the other, and the slider can be easily bent. Further, in the case where the slider is formed of a thin metal plate for weight reduction and the target member is fixed to the slider with a screw, the depth of the screw hole may not be sufficiently secured in the thin-plate slider. However, according to the present invention, since the metal plate is projected cylindrically by deep drawing or burring and the threaded hole is formed by forming the thread groove in the inner peripheral surface of the projection, the depth of the threaded hole can be made larger than the plate thickness of the slider, and the target member can be firmly fastened to the slider.

Drawings

Fig. 1 is a perspective view showing a state in which a side portion of a track rail is partially cut away, showing an embodiment of a linear guide unit according to the present invention.

Fig. 2 is a plan view showing the linear guide unit of fig. 1.

Fig. 3 is a sectional view showing the linear guide unit along line III-III of fig. 2.

Fig. 4 is a side view of the slider showing a state where the rail guide is removed from the linear guide unit of fig. 1.

Fig. 5 is a side view of the slider in the linear guide unit of fig. 1 as viewed from an end in the sliding direction.

Fig. 6 is a sectional view showing the slider along line VI-VI of fig. 5.

Fig. 7 is an explanatory view showing a manufacturing process of a slider in the linear guide unit of fig. 1.

Fig. 8 is a sectional view for explaining a manufacturing process of the mounting hole formed in the metal plate along a line VIII-VIII in fig. 7 (b).

Fig. 9 is a sectional view for explaining a manufacturing process of a return path formed in the metal plate along a line IX-IX in fig. 7 (c).

Fig. 10 is an enlarged side view for explaining a manufacturing process of the direction change path formed in the metal plate in fig. 7 (d). .

Fig. 11 is an enlarged bottom view of the direction change path of fig. 10 as viewed from the direction of introduction of the rolling element.

Fig. 12 is an explanatory view showing a manufacturing process of the track rail in the linear guide unit of fig. 1.

Fig. 13 is a perspective view showing an example of oil supply of the micro grease squirter that supplies grease to the return path of the slider in the linear guide unit.

Fig. 14 is an enlarged perspective view of the region denoted by symbol E in fig. 13.

Fig. 15 is an explanatory view showing a state where grease is supplied to the slider of fig. 13, viewed from another angle, and a state where a nozzle of the micro grease squirt is inserted into a gap formed in the slider.

Description of reference numerals

1 track guide rail

2 sliding part

3 rolling ball (rotor)

4 side part (track guide)

5 bottom (base of track guide)

6 Upper part (sliding part)

7 sleeve part (sliding part)

8 end cap part (sliding part, sealing part)

9 Metal board (for track guide rail forming processing)

10 Metal plate (for sliding parts forming)

11 track groove (first track groove, track guide)

12 track groove (second track groove, sliding part)

13 track path (10+11)

14 Return Path (slide)

15 Direction switching path (sliding piece)

16 projection (sliding piece, direction switching path)

17 mounting hole (track guide)

18 mounting screw hole (sliding part)

19 boss part of mounting hole (projection, sliding part)

20 projection (position of direction switching path, sliding piece)

21 notch part (between the sleeve part and the end part of the metal plate)

22 bending part (part of the direction switching path, sliding part)

23 end (formed by an end cap)

24 circulation path (13+14+15)

25 gap (forming part of return path)

26 Upper forming part (Metal plate 10)

27 Sleeve forming part (Metal plate 10)

28 end cap forming part (Metal plate 10)

29 base (sleeve forming part, track groove 12)

30 front end (sleeve forming part, return path 14)

31 edge part (end cover part, direction switching path)

32 side forming part (Metal plate 9)

33 recess (track guide)

34 bottom forming part (Metal plate 9)

35 micro oil injector

36 spray nozzle

Detailed Description

Hereinafter, an embodiment of the linear guide unit and the method of manufacturing the same according to the present invention will be described with reference to the drawings. As shown in fig. 1 to 6, the linear motion guide unit is applied to a sliding portion of a wheelchair lifting device of a welfare vehicle such as a drawer of furniture, a toy, or the like, and includes a slider 2 that moves relative to a rail guide 1 in a longitudinal direction. The linear motion guide unit is characterized by comprising a track guide rail 1 and a sliding piece 2, wherein the track guide rail 1 is formed by a metal plate 9 into a groove-shaped concave part 33 with a U-shaped cross section; the slider 2 is disposed in a U-shaped cross-sectional recess 33 of the track rail 1 and is disposed so as to be relatively slidable via balls 3 as a plurality of rolling bodies, and the slider 2 is formed of one metal plate 10.

The track rail 1 is formed to have a bottom portion 5 constituting a base portion and a pair of side portions 4 opposed to each other on both sides of the bottom portion 5 and extending upright in a longitudinal direction, and track grooves 11 (first track grooves) in which the respective balls 3 rotate are formed in the side portions 4. The track rail 1 is formed by, for example, punching a flat plate-like metal plate 9 of chromium molybdenum steel to be plastically deformed into a U-shape and to form a recessed portion 33 having a groove-like cross section. A plurality of mounting holes 17 are formed in the bottom portion 5 of the rail guide 1, and bolts or the like are inserted into the mounting holes 17 when the rail guide 1 is mounted on a frame or a base (not shown) of a structure. Track grooves 11 for allowing the balls 3 to rotate are formed on both sides of the track rail 1, i.e., on the pair of side portions 4. The track groove 11 is formed so that the side portion 4 of the track rail 1 protrudes outward in a curved shape and the inside thereof has a cross-sectional R shape.

The slider 2 is formed by plastically deforming a metal plate 10 made of chromium molybdenum copper, for example, by press forming. The slider 2 is formed by forming a single metal plate 10. The slider 2 is disposed inside the U-shaped member of the rail guide 1, and is configured to be slidable along the rail guide 1 via the balls 3. The slider 2 mainly has: an upper portion 6; a pair of sleeve portions 7 which are opposed to each other on both sides thereof and extend in the longitudinal direction to hang down; and end caps 8 formed at both ends 23 of the upper portion 6 and the sleeve portion 7, respectively, and hanging from the upper portion 6. In the sleeve portion 7 of the slider 2, track grooves 12 (second track grooves) and return paths 14 are formed, the track grooves 12 extending along the track grooves 11 of the track rail 1 and allowing the balls 3 to roll, and the return paths 14 extending parallel to the track grooves 12. The end cover portion 8 is formed with an arcuate direction change path 15, and the arcuate direction change path 15 is formed as a projection 16 that communicates the end portions of the track path 13 and the return path 14, each of which is formed by the track groove 11 and the track groove 12. In the present embodiment, the inner wall surface of the direction change path 15 is formed by the end 23 of the sleeve 7. The balls 3 of the rotating body roll along a circulating path 24, which is composed of the track path 13, the return path 14, and the pair of direction changing paths 15 on both end sides of the slider 2, in accordance with the relative reciprocation of the slider 2 with respect to the track rail 1. The tip of the end portion 23 is formed in an R shape so that the ball 3 can smoothly roll in the direction change path 15.

In the linear guide unit, mounting screw holes 18 for mounting an object member such as a drawer are formed in the upper portion 6 of the slider 2, and for example, one of the screw holes is formed in each corner portion. The mounting screw hole 18 is formed in the inner peripheral surface of a cylindrical boss portion 19 that projects a part of the upper portion 6 to the rear surface side. Each mounting screw hole 18 is a screw hole having a screw groove (not shown) formed in an inner peripheral surface of a boss portion 19 protruding cylindrically toward the rear surface of the mounting portion. Further, a rail groove 12 curved inward in an arc shape is formed on the base side of the sleeve 7, and a return path 14 curved in a cylindrical shape is formed on the tip side of the sleeve 7. A gap 25, which is a slit-shaped opening, can be formed in the cylindrical joint region forming the return path 14, but the gap 25 is formed to be smaller than the diameter of the ball 3 so that the ball 3 does not fall. For example, as shown in fig. 13 to 15, the nozzle 36 of the micro grease squirt 35 can be inserted into the cutout portion 21 described later in the gap 25, and then inserted into the gap 25, so that grease can be supplied from the nozzle 36 to the return path 14. The return path 14 is located more inward than the track groove 12 of the sleeve 7. Further, the direction change paths 15 are formed in the end cap portions 8 of the slider 2, respectively, and the direction change paths 15 hang down on the bottom portion 5 of the track rail 1 and cover both end portions 23 of the sleeve portion 7, respectively. In the linear guide unit, a projection 20 for supporting the ball 3 from the track path 13 toward the direction change path 15 is formed at the front end of the direction change path 15 on the track path 13 side, and the projection 20 is disposed in the track groove 11 of the track rail 1 so as to project in an R-shape.

Next, a method of manufacturing the linear motion guide unit of the present invention will be described with reference to fig. 7 to 10. In the method of manufacturing the linear guide unit according to the present invention, the one metal plate 10 used for manufacturing the slider 2 is formed by press working or the like from the upper portion forming portion 26 forming the upper portion 6, the sleeve portion forming portion 27 forming the sleeve portion 7, and the end cap portion forming portion 28 forming the end cap portion 8. A cutout portion 21 is cut in the metal plate 10 between the upper formation portion 26 and the end cover formation portion 28. Here, the metal plate 10 for forming the slider 2 is formed with an upper forming portion 26, a sleeve forming portion 27, and an end cap portion forming portion 28 by processing such as punching, and a cutout portion 21 is formed between the upper forming portion 26 and the end cap portion forming portion 28.

Fig. 7 shows a manufacturing process from the pressed metal plate 10 to the product slider 2 (step S1 to step S4) in the method of manufacturing the linear guide unit. The metal plate 10 which has been press-worked into the shape described above is punched by punching or the like, and the boss portion 19 (see fig. 8) is formed by burring the punched position so as to protrude to the back side (step S1). The mounting screw hole 18 forming the upper portion 6 is threaded into the inner peripheral surface of a boss portion 19 shown in fig. 8. The sleeve 7 is formed by press forming so as to be easily subjected to bending. As shown in fig. 9, the track groove 12 and the return path are formed in the sleeve portion 7 by bending (step S2). The end cap portion forming portion 28 forming the direction change path 15 of the end cap portion 8 is formed by crimping (step S3), and as shown in fig. 10 and 11, the end cap portion forming portion 28 forms the edge portion 31, the direction change portion 15 formed by the bent portion 22, and the protrusion portion 20. Next, the end cap portion 8 is formed so as to be able to be easily subjected to bending by press forming (step S4). The sliders 2 having substantially the same plate thickness are formed through steps S1 to S4, which are manufacturing steps.

The metal plate 10 forming the slider 2 is a metal plate having substantially the same thickness. At least one of the track rail 1 and the slider 2 is subjected to a surface hardening treatment for improving the wear resistance of the track grooves 11 and 12 and prolonging the life. The track rail 1 can be formed by forming one metal plate 9. For example, as shown in fig. 12, the metal plate 9 is bent by press forming from the bottom portion 5 and the pair of side portions 4 which are opposed to each other on both sides thereof and extend vertically in the longitudinal direction, and is formed into a U-shaped cross-sectional recess 33, and the rail groove 11 formed in the side portion 4 is formed by press forming.

In the method of manufacturing the linear motion guide unit, one metal plate 10 is formed by punching a hole in an upper portion forming portion 26 of an upper portion 6 constituting a slider 2, sleeve forming portions 27 of a pair of sleeves 7 constituting the slider 2 positioned on both sides in a width direction of the upper portion forming portion 26, and cap forming portions 28 of cap portions 8 constituting the slider 2 positioned on both ends in a longitudinal direction of the upper portion forming portion 26, the sleeve forming portion 27 is formed by punching the sleeves 7 hanging at an angle of substantially 90 ° with respect to the upper portion 6 from both sides in the width direction of the upper portion forming portion 26, that is, the angle formed between the sleeves 7 and the upper portion 6 is substantially 90 °, the slider 2 is formed in a U-shaped cross section by a pair of the sleeves 7 and the upper portion 6, semicircular track grooves 12 are formed by punching at positions of the respective sleeves 7 close to a base portion 29, the respective track grooves 12 are formed in a two-point contact with the ball 3, a ball load path is formed in a so-called an arcuate track groove 13, and a ball contact path is formed in a three-point contact arc shape, and a ball contact path is formed in a so-point contact path 3513, which is not limited to a ball load, as shown in a contact with the ball 3.

Further, the front end portion 30 of each sleeve forming portion 27 is formed with a return path 14 through which the balls 3 of the unloaded rolling body can roll. The return path 14 is formed by, for example, crimping to turn back the sleeve forming portion 27 into a cylindrical shape inside the slider 2. The inner diameter of the return path 14 is set slightly larger than the diameter of the ball 3, reducing the contact area of the ball 3 with the return path 14 and reducing the sliding resistance. End caps 8 are provided at both ends of the upper portion 6 in the sliding direction, respectively, so as to seal both ends of the U-shaped slider 2. Each end cap 8 is provided with a direction change path 15 that communicates the track path 13 and the return path 14. The direction change path 15 includes: an arc-shaped passage portion for changing the traveling direction of the ball 3, and a protrusion portion 20 for lifting the ball 3 introduced from the raceway path 13 to the direction change path 15. The direction change path 15 is formed so as to connect the track path 13 and the return path 14, that is, so as to cross. The projection 20 located on the track path 13 side of the direction change path 15 is formed to project in an R shape toward the track groove 11 of the track rail 1 toward the track path 13, in other words, to extend to a deep position of the track groove 11. The protrusion 20 is formed to lift the ball 3 rolling on the raceway path 13 toward the direction change path 15, and to smoothly roll the ball 3 toward the direction change path 15. The slider 2 is formed with a circulating path 24 that endlessly circulates by rolling along the track path 13, the direction change path 15 on one end side, the return path 14, and the direction change path 15 on the other end side. Further, as shown in fig. 6, since the projecting portion 16 having an end portion projecting in an R-shape from the inner peripheral side to the outer peripheral side is formed on the inner peripheral side of the direction change path 15, the ball 3 is smoothly guided along the outer peripheral side of the direction change path 15 without being caught by a connecting portion between the raceway path 13 and the direction change path 15 or between the return path 14 and the direction change path 15.

First, a manufacturing process of the track rail 1 in the linear guide unit will be described with reference to fig. 12. In the manufacturing process of the track rail 1, a metal plate 9, which is a flat plate-like thin plate, is formed by press working. Next, the metal plate 9 is press-formed by a predetermined die to form the rail groove 11 in the side portion forming portion 32, and the mounting hole 17, which is not shown but is necessary, is formed by press working (step S21). Next, press forming is performed using a predetermined die set in advance, so that the side forming portions 32 are bent substantially 90 ° with respect to the bottom forming portion 34 (step S22). Through this manufacturing process, the metal plate 9 is formed into the track rail 1 composed of the pair of side portions 4 and the bottom portion 5

Next, a manufacturing process of the slider 2 in the linear guide unit will be described with reference to fig. 7. Further, the plurality of sliders 2 can be continuously manufactured by continuously performing the sequential press working of the method of manufacturing the slider 2 of fig. 7. In the manufacturing process of the slider 2, the metal plate 10, which is a flat plate-like thin plate, is press-worked to form a shape including the upper forming portion 26, the sleeve forming portions 27 located on both sides in the width direction of the upper forming portion 26, and the cap forming portions 28 located on both ends in the longitudinal direction of the upper forming portion 26. The boss portion 19 is formed by burring the upper portion forming portion 26 of the metal plate 10 formed into a predetermined shape and protruding in a cylindrical shape as shown in fig. 10. A thread groove (not shown) is formed in the inner peripheral surface of the boss portion 19 by tapping. By these processes, mounting screw holes 18 for mounting the target member can be formed in the upper portion 6 of the slider 2. In this way, since the boss portion 19 from which the metal plate 10 protrudes is formed as the mounting screw hole 18, the mounting screw hole 18 can be formed deeper than the thickness of the metal plate 10. Next, the rail groove 12 is formed on the base 29 side and the return path 14 is formed on the tip side 30 of the sleeve forming portion 27 of the metal plate 10 in which the attachment screw hole 18 is formed. The rail groove 12 is formed by press-forming the base portion side 29 of the sleeve portion 7 with a predetermined die, and is formed so as to be curved so as to be concave in an arc shape in cross section (V-shaped in cross section) as shown in fig. 9. The return path 14 is formed by press-forming the base portion side 29 of the sleeve portion 7 with a predetermined die, and is formed by bending into a cylindrical shape in cross section as shown in fig. 9. At this time, the gap 25 of the joint of the cylinder of the return path 14 can be formed to a size that does not drop the ball 3. Thereby, the balls 3 rolling on the return path 14 are held in the return path 14 so as not to fall from the return path 14. Further, the track groove 12 and the return path 14 can be formed by either a method in which the track groove 12 and the return path 14 are formed simultaneously by press forming or in which the track groove 12 and the return path 14 are formed separately.

Next, as shown in fig. 9, the direction change path 15 is formed by press forming the metal plate 10 having the track groove 12 and the return path 14 formed in the sleeve forming portion 27. The direction change path 15 is formed at the end cap portion forming portions 28 located at both ends in the sliding direction of the upper portion 6. Specifically, both ends of the upper portion 6 are extended in the sliding direction of the slider 2 to form a pair of end caps 8, and as shown in fig. 10 and 11, the end caps 8 are bent into an arc shape by press forming. Thereby, a direction change path 15 for changing the traveling direction of the ball 3 is formed. The direction change path 15 is formed by making the end cover portion forming portion 28 formed with the direction change path 15 hang down from the upper forming portion 26 at both ends in the sliding direction of the upper forming portion 26. Further, the sleeve portion 7 forming the track groove 12 and the return path 14 is bent by press forming at substantially 90 ° to the upper portion 6 and hung down, thereby forming the slider 2 formed in a U shape by the upper portion 6 and the sleeve portion 7. At this time, the force when the sleeve portion 7 is bent is not transmitted to the end cap portion 8 side by the notch portion 21 provided at the base portion of the end cap portion 8. Next, the end caps 8 at both ends of the upper portion 6 are bent perpendicularly toward the bottom portion 5, which is the bottom portion of the track rail 1. Thereby, the end cap portions 8 are arranged in such a manner that both ends of the slider 2 in the sliding direction, or the sleeves 7, are closed. Specifically, the end cap portion 8 is bent perpendicularly to the upper portion 6 at substantially 90 ° using a predetermined die or a pressing plate. At this time, since the cutout portion 21 is formed in the base portion of the end cover portion 8 in the metal plate 10, the end cover portion forming portion 28 can be easily bent.

The sliding member 2 formed by pressing in the above-described manufacturing process is subjected to surface hardening treatment such as carburizing and quenching, tempering, carbonitriding, soft nitriding, and hard chrome plating, to thereby form the sliding member 2 having substantially the same plate thickness in the present example. According to the present embodiment as described above, since the slider 2 can be formed only with one metal plate 10, the cost of the slider 2 can be reduced, the number of components for the linear guide unit can be reduced, and the cost of the unit itself, the number of assembly steps, and the number of steps for managing the component arrangement can be reduced. In addition, since the slider 2 having substantially the same plate thickness is formed by press-forming one metal plate 10, a portion having a small plate thickness does not appear. Therefore, the problem of the strength of the slider 2 being lowered due to the reduction in the thickness of the metal plate 10 does not occur. Further, since the return path 14 through which the unloaded balls 3 roll is formed in a cylindrical shape, the balls 3 do not fall from the return path 14, and therefore, it is not necessary to push the balls 3 that roll through the return path 14 with the track rail 1. Therefore, the increase in sliding resistance due to the sliding contact between the balls 3 rolling on the return path 14 and the track rail 1 can be prevented. Further, since the protrusion 20 for lifting the ball 3 from the raceway path 13 to the direction change path 15 is provided, the ball 3 from the raceway path 13 to the direction change path 15 can be smoothly circulated. Further, the cutout 21 formed in the base portion of the direction change path 15 makes it difficult for the force generated when the sleeve 7 is bent to be transmitted to the direction change path 15, and the end cap 8 can be easily bent. Further, in the case where the slider 2 is formed of the thin metal plate 10 in order to reduce the weight of the slider 2, when the target member is fixed to the slider 2, the thin slider 2 may not be able to secure a sufficient depth of the mounting screw hole 18. However, according to the present invention, since the metal plate 10 is projected in a cylindrical shape by burring and a thread groove is formed as the mounting screw hole 18 on the inner peripheral surface of the boss portion 19 which is the projected portion, the depth of the mounting screw hole 18 can be formed deeper than the thickness of the slider 2, and the target member can be firmly fastened.

In the linear guide unit of the present embodiment, the metal plates 9 and 10 are made of chrome molybdenum steel, but not limited thereto, and for example, stainless steel may be used. In addition, when the rail groove 12 needs to be harder, the carbonitriding treatment may be followed by quenching and tempering. A known surface treatment may be performed as a rust-proof measure without performing a heat treatment on the track rail 1 and the slider 2. In addition, in the case where more rust prevention measures are required, austenitic stainless steel such as SUS304, and ferritic stainless steel such as SUS43 may be used. Further, a cutout similar to the cutout 21 provided at the base portion of the direction change path 15 may be provided between the sleeve forming portion 27 and the upper forming portion 26. Further, stoppers (not shown) may be attached to both ends of the track rail 1 so that the slider 2 does not fall off the track rail 1. In the linear motion guide unit of the present embodiment, a known lubricant such as a lubricating oil or grease can be used. Further, the sleeve portion 7 and the cap portion 8 are fixed by welding or the like, and the track path 13, the return path 14, and the direction change path 15 can be firmly connected. The method of manufacturing the linear guide unit according to the present embodiment is not limited to the above, and known press forming may be employed. The rolling elements are not limited to balls, and cylindrical rollers (not shown) may be used. The boss portion 19 may be formed by deep rolling or the like. The track rail 1 is not limited to the production by press molding, and may be produced by a known processing method such as extrusion molding, stretch molding, roll molding, spinning, calendering, or roll molding.