Linear guide

Abstract

To provide a linear guide by which a contact area between a lubricant supply member and a guide rail is reduced in a simple and inexpensive manner, so that lubricant can be supplied to the guide rail stably for a long period.SOLUTION: A linear guide includes: a guide rail; a slider engaged across the guide rail so as to be slidable; and a lubrication unit attached to an axial end of the slider and having a lubricant supply member capable of impregnation with lubricant. The lubricant supply member comprises an opposing part that faces the guide rail, including a protruding part that slides on the guide rail, wherein the opposing part is provided, along a longitudinal cross-section, with a contact part in contact with the guide rail and a non-contact part out of contact with the guide rail.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a linear guide equipped with a lubrication unit. [Background technology]

[0002] A linear guide comprises a guide rail extending in the axial direction and a slider mounted on the guide rail so as to be movable relative to the guide rail, and the slider moves relative to the guide rail in the axial direction via a plurality of rolling elements (balls) that circulate between rolling element rolling grooves formed in the guide rail and the slider. In order to use a linear guide stably over a long period of time, it is important to supply a sufficient amount of lubricant to the rolling element rolling grooves and the balls to maintain a good lubricated state.

[0003] For this reason, a linear guide has been disclosed in which a porous lubricant supply member containing a lubricant is housed in a case and attached to the end of the slider, and the lubricant is supplied from the lubricant supply member that contacts the rolling element rolling grooves of the guide rail. However, when the amount of lubricant impregnated in the lubricant supply member decreases over long-term use, the lubricant supply member shrinks and is no longer able to maintain contact with the rolling element rolling grooves of the guide rail.

[0004] Patent document 1 discloses a linear guide that is provided with a non-contact seal that restricts contact between the lubricant supply member and the guide rail's rolling element contact portion and any portion other than the vicinity thereof, thereby reducing the contact area between the lubricant supply member and the guide rail. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 10-176713 Summary of the Invention [Problem to be solved by the invention]

[0006] Patent Document 1 aims to reduce the contact area by having the lubricant supply member contact only the ball contact portion of the groove in the guide rail, but there is a problem in that if the contact state between the lubricant supply member and the guide rail changes, the lubricant supply member may no longer contact the ball contact portion.

[0007] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a linear guide that can easily and inexpensively reduce the contact area between the lubricant supply member and the guide rail, thereby stably supplying lubricant to the guide rail for a long period of time. [Means for solving the problem]

[0008] The above object of the present invention can be achieved by the following configuration. (1) a guide rail; a slider that slidably engages with the guide rail so as to straddle the guide rail; a lubrication unit having a lubricant supply member that can be impregnated with a lubricant and attached to an end portion of the slider in the axial direction, the lubricant supplying member has a facing portion facing the guide rail, the facing portion including a protrusion that slides on the guide rail, The facing portion is provided with a contact portion that contacts the guide rail and a non-contact portion that does not contact the guide rail along a longitudinal cross section. Linear guide. [Effects of the Invention]

[0009] According to the linear guide of the present invention, the contact area between the lubricant supplying member and the guide rail can be reduced with a simple and low-cost configuration, and lubricant can be supplied to the guide rail stably for a long period of time. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view of a linear guide according to the present invention. [Figure 2] FIG. 2 is a perspective view of the slider shown in FIG. [Figure 3]FIG. 3 is a partially exploded perspective view of the slider shown in FIG. [Figure 4] FIG. 4 is a partially exploded perspective view of the lubrication unit. [Figure 5] FIG. 5(A) is a cross-sectional view of the main part showing the opposing portion, and FIG. 5(B) is a cross-sectional view of the main part showing a modified example of the opposing portion. [Figure 6] FIG. 6 is a side view of a main part showing the opposing portion of the second embodiment. [Figure 7] FIG. 7 is a side view of a main part showing the opposing portion of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, linear guides (linear guiding devices) according to each embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the up-down direction, width direction, and axial direction of the slider respectively represent directions in a state in which the slider is assembled to a guide rail arranged with its longitudinal direction horizontal, and the width direction of the slider is a direction perpendicular to the longitudinal direction of the guide rail and the up-down direction of the slider, and is also referred to as the left-right direction, and the axial direction of the slider is a direction along the longitudinal direction of the guide rail, and is also referred to as the front-rear direction.

[0012] (First embodiment) The configuration of the linear guide will be described with reference to Figs. 1 to 5(B). Fig. 1 is a perspective view of a linear guide according to the present invention, Fig. 2 is a perspective view of a slider, Fig. 3 is a partially exploded perspective view of the slider, Fig. 4 is a partially exploded perspective view of a lubrication unit, Fig. 5(A) is a cross-sectional view of a main part showing an opposing portion, and Fig. 5(B) is a cross-sectional view of a main part showing a modified example of the opposing portion. As shown in Fig. 1, a linear guide 10 of the first embodiment includes a linear guide rail 20 and a slider 30 that is assembled so as to straddle the guide rail 20 and slidably engages with the guide rail 20 via a plurality of rolling elements (balls) (not shown).

[0013] On both side surfaces 23 of the guide rail 20, rail-side track surfaces 21 having an approximately semicircular or gothic arch cross section are formed in the axial direction, and on the ridge where the top surface 24 of the guide rail 20 intersects with both side surfaces 23, rail-side track surfaces 22 having an approximately quarter-circular arc cross section are formed in the axial direction.

[0014] As shown in Figures 2 and 3, the slider 30 consists of a slider body 31, end caps 32 attached to both axial ends of the slider body 31, and lubrication units 33 attached to the axial ends of each end cap 32.

[0015] The slider body 31 is formed in a roughly U-shape and has slider-side raceway surfaces (not shown) on the inner surfaces of both sleeves that face the rail-side raceway surfaces 21, 22 of the guide rail 20, as well as a rolling element return path. The end cap 32, also formed in a roughly U-shape, has a curved path (not shown) that connects the slider-side raceway surfaces of the slider body 31 with the rolling element return path, and the rail-side raceway surfaces 21, 22, the slider-side raceway surface, the rolling element return path, and the curved paths at both ends form a rolling element circulating path. A plurality of balls are loaded in the rolling element circulating path so that they can roll freely.

[0016] The lubrication unit 33 includes a case 40 made of synthetic resin, a lubricant supplying member 50 housed in the case 40, and a side seal 60. This configuration can be seen in FIG.

[0017] The side seal 60 is a generally U-shaped steel plate that matches the outer shape of the end cap 32, and both sleeve portions 62 thereof have through holes 61 for mounting screws, and a connecting portion 63 that connects both sleeve portions 62 has a through hole 64 for a grease nipple. The side seal 60 and the guide rail 20 are not in contact with each other, and an elastic body 65 such as nitrile rubber or grease-containing polyurethane rubber is provided on the inside of the generally U-shaped steel plate to seal the gap between the slider 30 and the guide rail 20.

[0018] The case 40 is made by injection molding a synthetic resin such as polyacetal or polyamide, and is formed in a roughly U-shape with approximately the same size as the end cap 32. The case 40 may also be made by cutting or pressing a metal material such as steel or aluminum. The case 40 forms a housing portion 43 for fitting and housing the lubricant supplying member 50, which is made up of an outer peripheral wall 41 that covers the outer periphery of the housed lubricant supplying member 50, an inner wall 42 that covers one axial end of the housed lubricant supplying member 50, and pressing means 44 and 45 that protrude and are formed to press the housed lubricant supplying member 50 inward. This configuration can be seen in Figure 4. When viewed in the axial direction of the slider 30, the accommodating section 43 is an approximately U-shaped space surrounded by the inside of the outer wall 41, the first cylindrical section 44, the second cylindrical section 45, and the guide rail 20 into which the slider 30 is fitted.

[0019] The outer peripheral wall 41 is formed in a substantially U-shape to cover the upper surface, the outer sides of both side surfaces, and the lower end surface of the lubricant supplying member 50. As a result, the outer peripheral surface of the lubricant supplying member 50 accommodated in the accommodating portion 43 is covered by the outer peripheral wall 41, while the U-shaped inner peripheral surface, which is a recessed portion that faces the guide rail 20, is exposed.

[0020] The pressing means 44 , 45 have a first cylindrical portion 44 and a second cylindrical portion 45 . The first cylindrical portion 44 is an upper pressing means provided at the upper part of the inner surface of the U-shaped outer peripheral wall 41, approximately in the center in the left-right direction. The second cylindrical portion 45 is a side pressing means provided at approximately the center in the height direction on both the left and right sides of the inner surface of the U-shaped outer peripheral wall 41. The second cylindrical portion 45 also has screw insertion holes 45a for screwing the lubrication unit 33 to the slider body 31.

[0021] The lubricant supplying member 50 is formed from a porous material such as rubber or synthetic resin, or a tangled fiber material, and is configured to be impregnated with a lubricant. Examples of lubricants that can be used include mineral oil, synthetic oil, and grease. Examples of synthetic resins that can be used include polyurethane, polyethylene, and polypropylene. Examples of tangled fiber materials that can be used include wool felt, polyester fiber, nylon fiber, and acrylic fiber.

[0022] The lubricant supplying member 50 is formed in a generally U-shape so as to face the upper surface 24 of the guide rail 20 and both side surfaces 23 including the rail-side track surfaces 21 and 22 . The lubricant supplying member 50 has a first recess 53 and second recesses 54, 54 formed on its outer peripheral surface (outer edge). Approximately semicircular protrusions 51 are provided on the inner peripheral surfaces of both sleeve portions of the lubricant supplying member 50, for supplying lubricant by sliding against the rail-side raceway surface 21 of the guide rail 20. Furthermore, quarter-circular arc protrusions 52 are provided on the inner corners of the inner peripheral surface of the approximately U-shaped lubricant supplying member 50, for supplying lubricant by sliding against the rail-side raceway surface 22 of the guide rail 20. This configuration can be seen in Figures 3 and 4. Furthermore, on the inner peripheral surface of the lubricant supplying member 50 formed in a substantially U-shape, a facing portion 55 is formed, which is a surface facing both side surfaces 23, the upper surface 24, or the rail-side track surfaces 21, 22 of the guide rail 20. The facing portion 55 also includes protrusions 51, 52.

[0023] The first recess 53 is disposed approximately in the center of the upper end of the outer edge of the lubricant supplying member 50 and is formed so as to be open upward. The first recess 53 is formed in a substantially U-shape with two parallel flat surfaces facing each other in the width direction. The second recesses 54, 54 are arranged on both outer surfaces of the outer edge of the lubricant supplying member 50 and are formed in a generally U-shape that is open on the sides. The second recesses 54, 54 are formed in a generally U-shape with two parallel flat surfaces that face each other in the vertical direction, and the corners between the two flat surfaces and the vertical surface are curved.

[0024] When the first cylindrical portion 44 is press-fitted into the first recess 53 with the interference T1, a pressing force acts on the first recess 53 in a direction that widens the inner width of the first recess 53. As a result, the protrusions 51 and 52 of the lubricant supplying member 50 are displaced in the width direction, and the pressing force of the protrusions 51 and 52 against the rail-side track surfaces 21 and 22 of the guide rail 20 increases.

[0025] When the second cylindrical portion 45 is press-fitted into the second recess 54 with the interference T2, a pressing force acts on the second recess 54 in a direction that widens the inner width of the second recess 54. As a result, the protrusions 51 and 52 of the lubricant supplying member 50 are displaced in the up-down direction toward each other, and the pressing force of the protrusions 51 and 52 against the rail-side track surfaces 21 and 22 of the guide rail 20 increases.

[0026] Therefore, the protrusions 51, 52 of the lubricant supplying member 50 reliably supply lubricant to the rail-side raceway surfaces 21, 22. The pressing force of the protrusions 51, 52 against the rail-side raceway surfaces 21, 22 is adjusted by the dimensions of the first and second recesses 53, 54 and the first and second cylindrical portions 44, 45.

[0027] Referring to FIG. 5(A), the facing portion 55 has a contact portion 56, a non-contact portion 57, and a step portion 58 along a cross section in the longitudinal direction. The cross-sectional shape in the longitudinal direction of the opposing portion 55 formed by the contact portion 56, the non-contact portion 57, and the step portion 58 is the same over the entire inner circumferential surface of the lubricant supplying member 50.

[0028] The contact portion 56 is a contact surface that comes into contact with both side surfaces 23 or the top surface 24 (including the rail-side track surfaces 21, 22) of the guide rail 20, and is formed on one side of the opposing portion 55 in the axial direction. The non-contact portion 57 is a non-contact surface that faces but does not come into contact with both side surfaces 23 or the top surface 24 (including the rail-side track surfaces 21, 22) of the guide rail 20, and is formed on the other axial side of the facing portion 55. 5(A), the step portion 58 is disposed in the axial center of the facing portion 55, and is formed in a crank shape so as to connect the contact portion 56 and the non-contact portion 57. The step portion 58 forms a gap h between the non-contact portion 57 and the guide rail 20.

[0029] According to this configuration, the step portion 58 and the non-contact portion 57 can reduce the contact area of ​​the opposing portion 55 of the lubricant supplying member 50 with the guide rail 20, without substantially changing the outer shape and thickness of the lubricant supplying member 50. Therefore, the amount of lubricant supplied (amount of oil discharged) from the lubricant supplying member 50 can be reduced without substantially changing the total amount of lubricant that the lubricant supplying member 50 can hold. This allows the lubrication unit 33 to continue to supply lubricant to the guide rail 20 for a longer period from the initial state. In addition, the maintenance-free period is also extended.

[0030] Furthermore, the period during which the lubricant can be supplied can be extended by reducing the amount of lubricant supplied from the lubricant supplying member 50. Specifically, the oil content, which is expressed as a volume percentage of the lubricant (oil amount) impregnated in the lubricant supplying member 50, can be set to 70% or more, more preferably 80% or more. This allows the lubrication unit 33 to be maintenance-free for a longer period of time.

[0031] Furthermore, the shape of the longitudinal cross section of the facing portion 55, which is provided with the contact portion 56, the non-contact portion 57, and the step portion 58, can be simplified. Furthermore, the facing portion 55 is formed over the entire inner circumferential surface of the lubricant supplying member 50. This makes it easier to process the lubricant supplying member 50, and therefore reduces manufacturing costs. Therefore, it is possible to arbitrarily set the shape of the protrusions 51, 52 that come into contact with the rail-side track surfaces 21, 22. That is, the protrusions 51, 52 may be shaped so as to come into contact only with the central portions of the rail-side track surfaces 21, 22 when viewed in the axial direction, or may be shaped so as to come into contact with the entire rail-side track surfaces 21, 22.

[0032] (Modification of the first embodiment) FIG. 5B is a cross-sectional side view of a main part showing a modification of the first embodiment. The facing portion 55 has a contact portion 56 , a non-contact portion 57 , and a step portion 58 . The contact portion 56 is a contact surface that comes into contact with the guide rail 20 and is formed in the axial center of the facing portion 55 . The non-contact portions 57, 57 are formed on both front and rear ends of the contact portion 56 in the axial direction so as to sandwich the contact portion 56 in the front-rear direction. A pair of stepped portions 58, 58 are arranged at the front and rear ends of the contact portion 56 so as to connect the contact portion 56 and the non-contact portion 57 together.

[0033] According to this configuration, compared to the first embodiment, the axial center side of the opposing portion 55 comes into contact with the guide rail 20, so that the sliding of the lubricant supplying member 50 on the guide rail 20 is more stable. In particular, the sliding of the protrusions 51, 52 of the lubricant supplying member 50 on the rail-side track surfaces 21, 22 is more stable.

[0034] (Second embodiment) 6 is a side view of the main part showing the opposing portion of the second embodiment. The lubricant supplying member 50 of this embodiment differs from the above-described example in the shape of the non-contact portion 57A.

[0035] The facing portion 55 has a contact portion 56 and a non-contact portion 57A. The contact portion 56 is a contact surface that comes into contact with the guide rail 20 and is formed in the axial center of the facing portion 55 . The non-contact portion 57A is a curved surface with a rounded chamfer that curves from the axial end of the contact portion 56 in the front-rear direction away from the guide rail 20, and is a non-contact surface that does not contact the guide rail 20.

[0036] According to this configuration, the contact area between the lubricant supply member 50 and the guide rail 20 can be reduced, thereby reducing the amount of oil discharged from the lubricant supply member 50 and also reducing the contact friction between the lubricant supply member 50 and the guide rail 20. Furthermore, by forming the non-contact portion 57A in an R-chamfered shape, even if there is a step portion (not shown) on the guide rail 20 that is made up of a joint, mounting hole, etc., the lubrication unit 33 (slider 30) can easily overcome the step smoothly.

[0037] (Third embodiment) 7 is a side view of the main part showing the opposing portion of the third embodiment. The lubricant supplying member 50 of this embodiment differs from the above-described example in the shape of the non-contact portion 57B.

[0038] The facing portion 55 has a contact portion 56 and a non-contact portion 57B. The contact portion 56 is a contact surface that comes into contact with the guide rail 20 and is formed in the axial center of the facing portion 55 . The non-contact portion 57B is a C-chamfered inclined surface that slopes from the axial end of the contact portion 56 toward the front-rear direction, away from the guide rail 20, and is a non-contact surface that does not contact the guide rail 20. The angle X at which the non-contact portion 57B is inclined relative to the contact portion 56 is preferably 30° or less.

[0039] According to this configuration, the contact area between the lubricant supply member 50 and the guide rail 20 can be reduced, thereby reducing the amount of oil discharged from the lubricant supply member 50 and also reducing the contact friction between the lubricant supply member 50 and the guide rail 20.

[0040] The present invention is not limited to the above-described embodiments, and modifications and improvements are possible as appropriate.

[0041] As described above, the present specification discloses the following: (1) a guide rail; a slider that slidably engages with the guide rail so as to straddle the guide rail; a lubrication unit having a lubricant supply member that can be impregnated with a lubricant and attached to an end portion of the slider in the axial direction, the lubricant supplying member has a facing portion facing the guide rail, the facing portion including a protrusion that slides on the guide rail, The facing portion is provided with a contact portion that contacts the guide rail and a non-contact portion that does not contact the guide rail along a longitudinal cross section. Linear guide This configuration reduces the contact area between the lubricant supplying member and the guide rail without substantially changing the amount of lubricant held by the lubricant supplying member. Furthermore, since the processing of the lubricant supplying member is simplified, a lubrication unit that can stably supply lubricant to the guide rail for a long period of time can be manufactured easily and at low cost.

[0042] (2) The non-contact portion is a curved surface with a rounded chamfer that is continuous with the contact portion at a tangent line. (1) The linear guide described above. According to this configuration, even if there is a step (not shown) on the guide rail, such as a joint or a mounting hole, the lubrication unit can easily overcome the step smoothly.

[0043] (3) The facing portion is formed on the inner peripheral surface of the lubricant supplying member, which is formed in a U-shape along both side surfaces and an upper surface of the guide rail, The opposing portions have the same longitudinal cross-sectional shape, A linear guide according to (1) or (2). According to this configuration, the non-contact portion is formed only on the inner circumferential surface of the lubricant supplying member, so that the manufacturing cost can be kept low.

[0044] (4) The oil content of the lubricant impregnated in the lubricant supply member is set to 80% or more. The linear guide according to any one of (1) to (3). According to this configuration, the lubricant supply member can increase the amount of lubricant impregnated while reducing the amount of lubricant supplied, making it possible to supply lubricant to the guide rail for a longer period of time and extending the maintenance-free period. [Explanation of symbols]

[0045] 10 Linear guide 20 Guide rail 21 Rail side track surface 22 Rail side track surface 23 Both sides 24 Top side 30 sliders 31 Slider body 32 End cap 33 Lubrication Unit 40 cases 41 Peripheral wall 42 Inner wall 43 Storage unit 44 First cylindrical portion, pressing means 45 Second cylindrical portion, pressing means 50 Lubricant supply member 51 protrusion 52 protrusion 53 First recess 54 Second recess 55 Opposing part 56 Contact part 57,57A,57B Non-contact part 58 Step part 60 Side seal 61,64 Through holes 62 Both sleeves 63 Connecting part 65 Elastic Body

Claims

1. Guide rails and a slider that slidably engages with the guide rail so as to straddle the guide rail; a lubrication unit having a lubricant supply member that can be impregnated with a lubricant and attached to an end portion of the slider in the axial direction, the lubricant supplying member has a facing portion facing the guide rail, the facing portion including a protrusion that slides on the guide rail, The facing portion is provided with a contact portion that contacts the guide rail and a non-contact portion that does not contact the guide rail along a longitudinal cross section. Linear guide.

2. The non-contact portion is a curved surface having an R-chamfer shape that is continuous with the contact portion at a tangent line. The linear guide according to claim 1 .

3. The facing portion is formed on an inner peripheral surface of the lubricant supplying member, which is formed in a U-shape along both side surfaces and an upper surface of the guide rail, The opposing portions have the same longitudinal cross-sectional shape, The linear guide according to claim 1 .

4. The oil content of the lubricant impregnated in the lubricant supply member is set to 80% or more. The linear guide according to any one of claims 1 to 3.

Images