TW202441089A - Linear Guides - Google Patents

Abstract

The present invention is a linear guide rail with a lubricating unit, the lubricating unit has a lubricant supply component and a housing, the lubricant supply component has a first recess formed at an upper position of the guide rail, a pair of second recesses formed at left and right side positions of the guide rail, and a protrusion slidably connected to the side track surface of the rail, the housing has a first pressing portion arranged in the first recess, and a pair of second pressing portions arranged in a pair of second recesses, the second pressing portion makes the interference of the lower pressing portion in the downward direction greater than the interference of the upper pressing portion in the upward direction.

Description

Linear Guides

The present invention relates to a linear guide rail having a slider with a lubrication unit installed therein.

Previously, linear guides had guide rails extending in the axial direction and sliders that were relatively movable across the guide rails. The sliders moved relatively axially on the guide rails through multiple rolling bodies (balls) circulating between the guide rails and the rolling grooves of the rolling bodies formed on the sliders. This type of linear guide is often used in linear motion mechanisms of various production equipment. In order to use the linear guide stably for a long time, it is important to supply sufficient lubricant to the rolling grooves of the rolling bodies and the rolling balls to maintain a good lubrication state.

Patent document 1 describes a linear guide rail, which can stably supply the lubricant impregnated in the lubricant supply member to the rolling groove of the rolling element of the guide rail for a long period of time by providing a porous lubricant supply member containing a lubricant at the axial end of the slider, a housing for housing the lubricant supply member, and a pressing mechanism for pressing the lubricant supply member housed in the housing in a manner that contacts the guide rail. [Prior technical document] [Patent document]

Patent document 1: Japanese Patent Publication No. 2018-40389

[The problem the invention is trying to solve]

The lubricating unit of Patent Document 1 can effectively press the protrusion formed on the inner corner of the lubricant supply member and a pair of protrusions formed on the inner sides of the two sleeves of the lubricant supply member toward the axial slideway surface formed on the ridge portion of the upper part of the guide slideway and the axial slideway surface formed on the left and right sides of the guide slideway by providing the concave portion formed on the upper surface and the left and right side surfaces of the lubricant supply member and the pressing portion pressed with a specified interference fit and fitted into the concave portion, so that the lubricant can be efficiently and continuously supplied to the slideway surface. However, as shown in FIG6 , when the lubricant supply member 50 accommodated in the housing shrinks in outer diameter due to shrinkage over time, or when the protrusion formed at the inner corner of the lubricant supply member by the pressing mechanism is strongly pressed by the guide rail, the two sleeves of the lubricant supply member are deformed in the direction away from the guide rail, and there is a risk that the lubricant supply to the rail surface will stop midway.

The present invention is made in view of the above-mentioned problems, and its purpose is to provide a linear guide rail that can efficiently and continuously supply lubricant impregnated in the lubricant supply member to the guide rail by making the lubricant supply member stably contact the side rail surface of the rail. [Technical means for solving the problem]

The above-mentioned purpose of the present invention is achieved by the following structure. [1] A linear guide rail comprising: a guide rail; a slider that is slidably engaged across the guide rail; and a lubricating unit mounted on an axial end of the slider; and the lubricating unit comprises: a lubricant supply member that is impregnated with lubricant to be supplied to the guide rail; and a housing that accommodates the lubricant supply member; the lubricant supply member comprises: a first recess formed at an upper position of the guide rail; a pair of second recesses formed at left and right side positions of the guide rail; and a protrusion that slides on the side rail surface of the guide rail; the housing comprises: The first pressing portion allows the first recess to move in the up-down direction of the slider and is arranged in the first recess in a manner of pressing the first recess outward in the width direction of the slider; and A pair of second pressing portions allow the second recess to move in the width direction of the slider and are arranged in the second recess in a manner of pressing the second recess in the up-down direction of the slider respectively; The second pressing portion has an upper pressing portion protruding in the upper direction of the second recess and a lower pressing portion protruding in the lower direction of the second recess, so that the interference of the lower pressing portion in the lower direction is greater than the interference of the upper pressing portion in the upper direction. [2] A linear guide rail as described in [1], wherein the interference of the second pressing portion in the vertical direction is within 20% of the width of the notch of the second recess. [3] A linear guide rail as described in [1] or [2], wherein the interference of the first pressing portion in the width direction is within 20% of the width of the notch of the first recess. [Effect of the invention]

According to the linear guide rail of the present invention, since the lubricant supply component in the housing can be prevented from being displaced downward and the contact of the lubricant supply component with the side track surface of the guide rail can be stabilized, the lubricant impregnated in the lubricant supply component can be efficiently and continuously supplied to the guide rail.

The linear guide rail (linear guide device) of each embodiment of the present invention is described in detail below based on the drawings. In addition, in the following description, the up-down direction, width direction, and axial direction of the slider respectively represent the directions of the state of the slider assembled in the guide rail arranged horizontally with the length direction. The width direction of the slider is perpendicular to the length direction of the guide rail and the up-down direction of the slider, also called the left-right direction, and the axial direction of the slider is along the length direction of the guide rail, also called the front-back direction.

The structure of the linear guide is described based on Fig. 1 and Fig. 2. Fig. 1 is a three-dimensional view of the linear guide of the present invention, and Fig. 2 is a three-dimensional view of a slider. As shown in Fig. 1, the linear guide 10 has a straight guide rail 20 and a slider 30 assembled in a manner straddling the guide rail 20 and slidably engaged via a plurality of rolling bodies (balls) not shown.

On the two side surfaces 23 of the guide rail 20, a rail side track surface 21 with a cross section of approximately semicircular or Gothic arc shape is formed in the axial direction, and on the edge portion where the upper surface 24 of the guide rail 20 and the two side surfaces 23 intersect, a rail side track surface 22 with a cross section of approximately 1/4 arc shape is formed in the axial direction.

As shown in FIG. 2 , the slider 30 is composed of a slider body 31 , end caps 32 mounted on both axial ends of the slider body 31 , and lubricating units 33 mounted on the axial ends of each end cap 32 .

The slider body 31 is formed in a substantially U-shaped shape, and has a slider side track surface (not shown) on the inner side surface of both sleeves that is opposite to the slider side track surfaces 21 and 22 of the guide slider 20, and has a rolling body return path. In addition, the end cover 32 formed in a substantially U-shaped shape has a curved path (not shown) that connects the slider side track surface of the slider body 31 and the rolling body return path, and the sliding rail side track surfaces 21 and 22, the slider side track surface, the rolling body return path, and the curved paths at both ends form a rolling body circulation path. In the rolling body circulation path, a plurality of balls are loaded so as to roll freely.

Next, the lubricating unit 33 is described based on Fig. 2 to Fig. 5(B). Fig. 3 is a front view of the lubricating unit, Fig. 4(A) is a front view of the housing, and Fig. 4(B) is a front view of the lubricant supply member. Fig. 5(A) is a front view showing the pressing force applied to the lubricant supply member by the second pressing portion, and Fig. 5(B) is a front view of the lubricating unit showing the state in which the lubricant supply member shrinks over time.

As shown in FIG. 2 , the lubricating unit 33 includes a housing 40 made of synthetic resin, a lubricant supply member 50 accommodated in the housing 40 , and a side seal 60 .

The side seal 60 is a substantially U-shaped steel plate that is consistent with the outer shape of the end cover 32. Through holes 61 for mounting screws are formed on both sleeves, and through holes 64 for grease interface are formed on the connecting portion connecting the two sleeves in the left and right directions. The side seal 60 does not contact the guide rail 20. In order to seal the gap between the slider 30 and the guide rail 20, an elastic body 65 containing nitrile rubber or grease-containing polyurethane rubber is provided on the inner side of the substantially U-shaped steel plate.

The lubricant supply member 50 is formed into a generally U-shaped shape with an open bottom so as to face the upper surface 24 of the guide rail 20 and the two side surfaces 23 of the rail side surfaces 21 and 22. In other words, the lubricant supply member 50 has a pair of left and right sleeves extending in the up-down direction and a left-right connecting portion connecting the upper ends of the two sleeves.

The lubricant supply member 50 is formed of a porous body such as rubber or synthetic resin, a fiber interwoven body, etc., and is impregnated with a lubricant. As the lubricant, mineral oil, synthetic oil, grease, etc. can be used. As the synthetic resin, polyurethane, polyethylene, polypropylene, etc. can be used. As the fiber interwoven body, wool felt, polyester fiber, nylon fiber, acrylic fiber, etc. can be used.

On the inner sides of the two side surfaces of the U-shaped lubricant supply member 50, there are protrudingly provided a substantially semicircular protrusion 51 for slidingly contacting the side rail surface 21 of the guide rail 20 to supply lubricant. In addition, on the inner corners of the two side surfaces and the upper surface of the U-shaped portion, there are protrudingly provided a 1/4 arc-shaped protrusion 52 for slidingly contacting the side rail surface 22 of the guide rail 20 to supply lubricant.

Furthermore, a first recess 53 opening upward is formed at the approximate center of the upper end of the lubricant supply member 50. Also, a second recess 54 opening laterally in a substantially U-shaped shape is formed on both outer side surfaces of the lubricant supply member 50. The first recess 53 is formed in a substantially U-shaped shape having two mutually parallel planes opposing in the width direction, and the second recess 54 is formed in a substantially U-shaped shape having two mutually parallel planes opposing in the vertical direction.

The housing 40 is made by injection molding a hard resin such as polyacetal or polyamide, and is formed into a substantially U-shaped shape of substantially the same size as the end cap 32. The housing 40 is formed with an outer peripheral wall 41 covering the outer peripheral portion of the lubricant supply member 50 accommodated therein, and an end wall 42 covering the axial end surface of the lubricant supply member 50, thereby forming a receiving portion 43 for accommodating the lubricant supply member 50. In addition, the housing 40 can also be made by cutting or stamping metal materials such as steel and aluminum.

A cylindrical first pressing portion 44 as an upper pressing mechanism is provided at the upper position of the guide rail 20 in the upper portion of the housing portion 43, in the substantially central portion in the left-right direction. A through hole 48 communicating with the through hole 64 for the grease interface is formed on the inner side of the first pressing portion 44. In addition, the first pressing portion 44 may be formed continuously on the outer peripheral wall 41 and the end wall 42.

On the left and right sides of the receiving portion 43, a cylindrical second pressing portion 45 as a side pressing mechanism is formed symmetrically at the approximately center in the height direction and arranged at the left and right side surfaces of the guide rail 20. In addition, a screw insertion hole 47 for screwing the lubricating unit 33 to the slider body 31 is provided on the inner side of the second pressing portion 45. In addition, the second pressing portion 45 can also be formed continuously on the outer peripheral wall 41 and the end wall 42.

The second pressing portion 45 has an upper pressing portion 45a in the upper half and a lower pressing portion 45b in the lower half. As shown in FIG. 3 and FIG. 4 (A), the lower pressing portion 45b is formed in such a manner that the protrusion amount in the vertical direction from the center of the screw insertion hole 47 is greater than that of the upper pressing portion 45a. Thus, the center of the second pressing portion 45 in the vertical direction is eccentric to the lower direction by a predetermined eccentricity σ relative to the center of the screw insertion hole 47, and the second pressing portion 45 is formed as a whole in an elliptical shape that is elongated in the vertical direction.

According to the above, by inserting the first pressing portion 44 of the housing 40 into the first recess 53 of the lubricant supply member 50 and inserting the second pressing portion 45 into a pair of second recesses 54, the lubricant supply member 50 can be accommodated in the receiving portion 43 of the housing 40. The structure can be referred to in FIG3.

Thus, the housing 40 can prevent the lubricant supply member 50 from being damaged during handling by accommodating the lubricant supply member 50. In particular, if the lubricant impregnation amount of the lubricant supply member 50 is 70% by weight or more, the amount of resin is reduced accordingly, and the strength of the lubricant supply member 50 is reduced, so the housing is used effectively.

At this time, since the outer diameter of the first pressing portion 44 is set to be larger than the inner width (left-right width) of the first recess 53, the first pressing portion 44 and the first recess 53 interfere with each other by interference T1 on each single side. Similarly, the second pressing portion 45 is set to be larger than the inner width (upper and lower width) of the second recess. Specifically, the upper pressing portion 45a only interferes with interference T2 by protruding above the upper surface of the inner width of the second recess 54, and only interferes with interference T3 by protruding below the lower pressing portion 45b and the lower surface of the inner width of the second recess 54. At this time, the interference T3 is set to be wider than the interference T2 (interference T3＞interference T2).

That is, the first pressing portion 44 is pressed into the first recess 53 with an interference T1, the upper side of the second pressing portion 45 is pressed into the second recess 54 with an interference T2, and the lower side is pressed into the second recess 54 with an interference T3. The structure can refer to Figure 3. In addition, the first pressing portion 44 applies a pressing force in the width direction to the first recess 53, but allows movement in the up and down directions without being restricted. In addition, the second pressing portion 45 applies a pressing force in the up and down directions to the second recess 54, but allows movement in the width direction without being restricted.

At this time, the interferences T2 and T3 of the second pressing portion 45 are preferably set to within 20% of the cut width of the second recess 54 pressed into the second pressing portion 45. Specifically, when the cut width of the second recess is 10 mm, the upper limit of the interference T3 is 2 mm. The interference T1 of the first pressing portion 44 is also preferably set to within 20% of the cut width of the first recess 53 pressed into the first pressing portion 44.

Next, the functions and effects of each pressing portion 44, 45 are described. By pressing the first pressing portion 44 into the first recess 53 with an interference fit T1, a pressing force in the left and right directions in the direction of expanding the inner width of the first recess 53 is applied to the first recess 53. As a result, the protrusions 51, 52 of the lubricant supply member 50 are displaced in the width direction, and the pressing force of the protrusions 51, 52 relative to the side rail surfaces 21, 22 of the guide rail 20 is increased.

Furthermore, by pressing the second pressing portion 45 into the second recess 54 with interference fits T2 and T3, a pressing force in the up-down direction in the direction of expanding the inner width of the second recess 54 is applied to the second recess 54. As a result, the protrusions 51 and 52 of the lubricant supply member 50 are displaced in the up-down direction approaching each other, so the pressing force of the protrusions 51 and 52 relative to the rail side rail surfaces 21 and 22 of the guide rail 20 is increased. This structure can be referred to FIG. 5 (A).

Furthermore, since the lower portion of the second recess 54 is pressed in by the lower pressing portion 45b with an interference T3 wider than the interference T2, the pressing force acting in the direction of closing the lower end sides of the two sleeves of the lubricant supply member 50, i.e., the open end sides, becomes stronger. Thereby, for example, even if the amount of lubricant impregnated in the lubricant supply member 50 decreases, the outer shape of the lubricant supply member 50 shrinks and deforms in the direction of the two sleeves moving apart, the lower pressing portion 45b can prevent the lubricant supply member 50 from deforming in the direction of the two sleeves moving apart. That is, it is possible to prevent the protrusion 51 of the lubricant supply member 50 from leaving the side rail surface 21 of the slide rail to become non-contact and cause the lubricant supply to stop midway. The structure can be referred to Figure 5 (B).

In addition, if the interference T3 is simply increased to make the second recess 54 face downward, the lubricant supply member 50 may be separated from the side track surface of the slide rail due to the force that causes the lubricant supply member 50 to move downward. However, according to the second pressing portion 45, by making the lower pressing portion 45b offset downward relative to the center of the screw insertion hole 47, the lubricant supply member 50 can be prevented from moving downward in the housing 40, and the protrusion 51 of the lubricant supply member 50 can be in stable contact with the lower side track surface 22 for a long time.

Therefore, the lubricant impregnated in the lubricant supply member 50 can be smoothly supplied from the protrusions 51 and 52 to the rail side surfaces 21 and 22. In addition, the pressing force of the protrusions 51 and 52 relative to the rail side surfaces 21 and 22 is adjusted by the sizes of the first recess 53 and the second recess 54 and the first pressing portion 44 and the second pressing portion 45.

In addition, the second pressing portion 45 may be configured such that the curvature R3 of the arc surface constituting the lower pressing portion 45b is greater than the curvature R2 of the arc surface constituting the upper pressing portion 45a. According to this configuration, the contact portion between the lower pressing portion 45b and the second recess 54 can prevent the lubricant supply member 50 from sinking significantly, and can prevent the housing 40 itself from moving downward.

In addition, the present invention is not limited to the above-mentioned embodiments, and can be appropriately modified and improved.

As mentioned above, the following matters are disclosed in this manual. (1) A linear guide rail, comprising: a guide rail; a slider that is slidably engaged across the guide rail; and a lubricating unit that is mounted on the axial end of the slider; and the lubricating unit has: a lubricant supply member that is impregnated with lubricant to be supplied to the guide rail; and a housing that accommodates the lubricant supply member; the lubricant supply member has: a first recess that is formed at an upper position of the guide rail; a pair of second recesses that are formed at left and right side positions of the guide rail; and a protrusion that slides on the side track surface of the guide rail; the housing has: The first pressing portion allows the first recess to move in the up-down direction of the slider and is arranged in the first recess in a manner of pressing the first recess outward in the width direction of the slider; and A pair of second pressing portions allow the second recess to move in the width direction of the slider and are arranged in the second recess in a manner of pressing the second recess in the up-down direction of the slider respectively; The second pressing portion has an upper pressing portion protruding in the upper direction of the second recess and a lower pressing portion protruding in the lower direction of the second recess, so that the interference of the lower pressing portion in the lower direction is greater than the interference of the upper pressing portion in the upper direction. According to this structure, since the lubricant supply member in the housing can be prevented from being displaced downward and the contact of the lubricant supply member with the side rail surface of the rail can be stabilized, the lubricant impregnated in the lubricant supply member can be efficiently and continuously supplied to the guide rail.

(2) A linear guide rail as described in (1), wherein the interference of the second pressing portion in the vertical direction is within 20% of the notch width of the second recess. According to this structure, the contact of the lubricant supply component with the side rail surface of the slide rail can be made more stable.

(3) A linear guide rail as described in (1) or (2), wherein the interference in the width direction of the first pressing portion is within 20% of the notch width of the first recess. According to this structure, the contact between the lubricant supply component and the side rail surface of the slide rail can be made more stable.

Although various embodiments are described above with reference to the drawings, the present invention is not limited to these embodiments. Those familiar with the art will understand that various modifications or amendments can be thought of within the scope of the patent application, and they are within the technical scope of the present invention. Furthermore, the constituent elements in the above embodiments can be combined arbitrarily within the scope of the invention.

In addition, this application is based on the Japanese patent application (Patent 2023-059008) filed on March 31, 2023, the contents of which are cited in this application as a reference.

10: Linear guide rail 20: Guide rail 21: Side rail surface 22: Side rail surface 23: Side surfaces 24: Upper surface 30: Slider 31: Slider body 32: End cover 33: Lubricant unit 40: Housing 41: Peripheral wall 42: End wall 43: Receptacle 44: First pressing part 45: Second pressing part 45a: Upper pressing part 45b: Lower pressing part 47: Screw insertion hole 48: Through hole 50: Lubricant supply member 51: Protrusion 52: Protrusion 53: 1st concave part 54: 2nd concave part 60: Side seal 61: Through hole 64: Through hole 65: Elastic body R2, R3: Curvature T1, T2, T3: Interference σ: Eccentricity

FIG. 1 is a perspective view of the linear guide rail of the present invention. FIG. 2 is a perspective view of the slider shown in FIG. 1. FIG. 3 is a front view showing a lubricating unit. FIG. 4(A) is a front view showing a housing, and FIG. 4(B) is a front view showing a lubricant supply member. FIG. 5(A) is a front view showing the pressing force applied to the lubricant supply member by the second pressing portion, and FIG. 5(B) is a front view showing the lubricating unit in a state where the lubricant supply member shrinks over time. FIG. 6 is an exploded perspective view showing a previous example of the lubricating unit.

20: Guide rail

21: Slideway side track surface

22: Slideway side track surface

23: Both sides

24: Upper surface

33: Lubrication unit

40: Shell

44: 1st pressing part

45a: Upper pressing part

45b: Lower pressing part

47: Screw insertion hole

48:Through hole

50: Lubricant supply component

51: protrusion

52: protrusion

53: 1st concave part

54: Second concave part

T1, T2, T3: Interference

σ: eccentricity

Claims (3)

A linear guide rail, comprising: a guide rail; a slider that is slidably engaged across the guide rail; and a lubricating unit mounted on the axial end of the slider; and the lubricating unit comprises: a lubricant supply member that is impregnated with lubricant to be supplied to the guide rail; and a housing that accommodates the lubricant supply member; the lubricant supply member comprises: a first recess formed at an upper position of the guide rail; a pair of second recesses formed at left and right side positions of the guide rail; and a protrusion that slides on the side track surface of the guide rail; the housing comprises: The first pressing portion allows the first recess to move in the up-down direction of the slider and is arranged in the first recess in a manner of pressing the first recess outward in the width direction of the slider; and A pair of second pressing portions allow the second recess to move in the width direction of the slider and are arranged in the second recess in a manner of pressing the second recess in the up-down direction of the slider respectively; The second pressing portion includes an upper pressing portion protruding in the upper direction of the second recess and a lower pressing portion protruding in the lower direction of the second recess, so that the interference of the lower pressing portion in the lower direction is greater than the interference of the upper pressing portion in the upper direction. The linear guide rail of claim 1, wherein the interference of the second pressing portion in the vertical direction is within 20% of the notch width of the second recess. For a linear guide rail as claimed in claim 1 or 2, the interference in the width direction of the first pressing portion is within 20% of the notch width of the first recess.