JP2022157874A - Cap for guide rail attachment hole of linear guide device and linear guide device - Google Patents

Abstract

To provide a cap for a guide rail attachment hole of a linear guide device which can block a rail attachment hole of a guide rail without forming a step, is adaptable to counterbore parts having various depths, and can prevent a sink of the cap caused by a secular change.SOLUTION: A cap 41 for a guide rail attachment hole of a linear guide device is fit to an upper part of a counterbore part 4b of a rail attachment hole 4 of a guide rail 3 constituting the linear guide device, and blocks the rail attachment hole 4 after being inserted with a bolt 6. The cap comprises: a cap head 41a having an outside diameter dimension corresponding to a hole diameter of the counterbore part 4b; and an insertion part 41b arranged at one end face of the cap head 41a in an axial direction, and inserted into the counterbore part 4b. Also, the insertion part 41b is formed into a cylindrical shape, and has a telescopic bellows structure extendable/retractable in the axial direction.SELECTED DRAWING: Figure 5

Description

The present invention provides guide rail mounting hole caps and linear guide devices for linear guide devices used in machine tools, injection molding machines, semiconductor manufacturing equipment, etc. Regarding.

Conventionally, a linear guide device (linear motion guide device) used in a machine tool or the like generally has a guide rail provided with rail-side rolling grooves on the left and right side surfaces, and the rail-side rolling grooves of the guide rail face each other. It fills the slider with the slider-side rolling groove at the position, the load rolling path composed of the rail-side rolling groove and the slider-side rolling groove, and the rolling element return path provided inside the slider. and a large number of rolling elements that can roll on the rolling path. End caps are attached to both ends of the slider in the axial direction, and direction changing paths for changing the direction of the rolling elements are formed in the end caps. As the rolling elements roll on the rolling path, the slider moves relative to the guide rail along the axial direction. The rolling elements rolling in the rolling path change direction in the end caps and then return to their original positions through rolling element return passages formed in the slider.

Since the guide rail is attached to a mounting portion of a machine base of a machine tool, a cutting machine, or the like using bolts, the guide rail is formed with rail mounting holes. The rail mounting hole has a counterbore portion that accommodates the head portion of the bolt and a shaft accommodation portion that accommodates the shaft portion of the bolt. The head of the bolt is configured so that it does not protrude from the upper surface of the guide rail when fixed to the surface.

In the linear guide device configured in this manner, foreign matter such as cutting powder and chips generated by using a machine tool or cutting machine tends to accumulate on the upper surface and side surfaces of the guide rail. In particular, on the upper surface of the guide rail, there is a problem that foreign matter tends to accumulate on the head of the bolt sunk in the counterbore. If left unattended, foreign matter accumulated on the bolt head will come into contact with the end cap as the slider moves, damaging the end cap or entering the inside of the slider, resulting in a smooth operation of the rolling elements inside the slider. May impede rolling. As a result, the travel accuracy and stop position accuracy of the slider may be degraded.

In recent years, therefore, various caps for linear guide devices have been proposed that have caps that block the openings of the rail mounting holes. For example, Patent Literature 1 proposes a synthetic resin cap that includes a disc-shaped flange portion and a cylindrical fitting portion that extends from the lower surface of the flange portion and is press-fitted into a counterbore. It is A burr storage groove is formed in the circumferential direction on the outer periphery of the fitting portion. Therefore, when the cap is hammered into the counterbore, burrs generated from the fitting portion can be accommodated, and the rail mounting hole can be closed with the cap without leaving foreign matter on the upper surface of the guide rail.

Further, Patent Document 2 discloses a cap having a cap head having an outer diameter dimension corresponding to the hole diameter of a countersunk hole of a guide rail, and a projection protruding downward from the cap head. When the cap configured in this manner is inserted into the countersunk hole, the bendable protrusion contacts the bolt head and is bent, so that the cap is horizontally stable on the bolt head. A cap can be supported.

WO2015/033486 Japanese Patent No. 5034892

By the way, the counterbore depth of the rail mounting holes of the linear guide device may differ from the dimensions (standard specifications) described in the catalog, etc., so in such cases, use the normally used cap. Can not do it. For example, in the cap described in Patent Document 1, the fitting portion has an outer diameter that provides an "interference fit" with the counterbore, and the cap is fitted to the counterbore of the mounting hole. Although the upper surface of the cap and the upper surface of the rail are substantially flush with each other, the cap may sink over time.

In addition, the cap described in Patent Document 2 can suppress sinking of the cap by having the projection contact the head of the bolt. , it is necessary to adjust the length of the projection.

Thus, if the counterbore depth differs from the standard specification by several millimeters, it is necessary to individually design the cap, which raises the problem of increased manufacturing costs. In addition, since it is necessary to manufacture caps corresponding to the respective rail mounting holes, the number of types of caps increases, and there arises a problem that it is necessary to secure a storage space.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides a cap that closes a rail mounting hole of a guide rail without a step, and which can be adapted to counterbore portions of various depths, and is capable of handling changes over time. To provide a guide rail mounting hole cap for a linear guide device and a linear guide device capable of preventing sinking of a guide rail.

The above object of the present invention is achieved by the following configuration (1) relating to a guide rail mounting hole cap for a linear guide device.
(1) A guide rail mounting hole cap that is fitted into a counterbore portion of a mounting hole of a guide rail constituting a linear guide device and closes the mounting hole into which a bolt is inserted,
a cap head having an outer diameter corresponding to the hole diameter of the counterbore;
an inserting portion provided on one axial end surface of the cap head portion and inserted into the countersunk portion;
The cap for the guide rail mounting hole of the linear guide device, wherein the insertion portion is cylindrical and has a bellows structure that expands and contracts in the axial direction.

Further, preferred embodiments of the present invention relating to guide rail mounting hole caps of a linear guide device relate to the following (2) to (6).
(2) The guide rail mounting hole cap for a linear guide device according to (1), wherein the other axial end surface of the cap head has a shape that rises gently toward the center.
(3) The guide rail mounting hole cap for a linear guide device according to (1) or (2), wherein the cap head has an outer diameter that provides an interference fit with respect to the hole diameter of the counterbore. .
(4) For a guide rail mounting hole of a linear guide device according to any one of (1) to (3), wherein the outer diameter of the insertion portion is larger than the diameter of the inscribed circle of the hexagonal hole in the bolt. cap.
(5) A guide rail mounting hole cap for a linear guide device according to any one of (1) to (4), wherein the cap head and the insertion portion are integrally formed.
(6) The guide of the linear guide device according to any one of (1) to (4), wherein the insertion portion configured as a separate member from the cap head is adhered to the cap head. Cap for rail mounting hole.

The above object of the present invention is achieved by the following configuration (7) relating to the linear guide device.
(7) a guide rail that has a plurality of rail mounting holes through which bolts can be inserted, and that is attached to a mounting surface using the bolts;
A linear guide device comprising a slider mounted so as to straddle the guide rail and capable of relative movement in the axial direction with respect to the guide rail,
The rail mounting hole of the guide rail includes a shaft receiving portion that receives the shaft portion of the bolt and a counterbore portion that receives the head portion of the bolt,
A guide rail mounting hole cap for a linear guide device according to any one of (1) to (6) is fitted to the counterbore portion of the rail mounting hole, and the head of the bolt and the insertion portion are fitted. is in contact with the linear guide device.

According to the present invention, it is possible to block the rail mounting holes of the guide rails without steps, to accommodate counterbore portions of various depths, and to prevent the cap from sinking due to changes over time. A guide rail mounting hole cap for a linear guide device can be provided.
In addition, according to the present invention, since the cap that closes the rail mounting hole of the guide rail without a step and is prevented from sinking due to deterioration over time is fitted into the rail mounting hole, foreign matter or the like is prevented from accumulating on the upper surface of the cap. can be suppressed, and it is possible to provide a linear guide device in which the travel accuracy and stop position accuracy of the slider are well maintained.

FIG. 1 is a perspective view showing an embodiment of a linear guide device according to the invention. FIG. 2 is a schematic top view of the linear guide device shown in FIG. 1 with a part of the top surface removed. FIG. 3 is a schematic front view of the linear guide device shown in FIG. 1 with a part of the front cut away. 4 is a back view of the end cap of the linear guide device shown in FIG. 1. FIG. FIG. 5 is a cross-sectional view showing an enlarged rail mounting hole of the linear guide device according to the present embodiment. FIG. 6(a) is a schematic diagram showing a state in which the insertion portion of the guide rail mounting hole cap of the linear guide device according to the present embodiment is extended, and FIG. FIG. 4 is a schematic diagram showing a state in which It is a top view which shows the top surface shape of the bolt used for the linear guide apparatus which concerns on this embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a guide rail mounting hole cap of a linear guide device and a linear guide device according to the present invention will be described in detail based on the drawings. Hereinafter, the guide rail mounting hole caps of the linear guide device may be simply referred to as "caps".

(Linear guide device)
First, embodiments of a linear guide device and guide rail mounting hole caps for the linear guide device according to the present invention will be described with reference to FIGS. 1 to 4. FIG.

As shown in FIG. 1, the linear guide device 1 according to the present embodiment is mounted so as to straddle a guide rail 3 extending in one direction and the guide rail 3, and is axially movable relative to the guide rail 3. and a slider 20 having a substantially C-shaped cross section. In the specification of the present application, the front-rear direction indicates the direction in which the slider 20 moves along the guide rail 3 , and the left-right direction indicates the width direction of the slider 20 attached to the guide rail 3 .

2 to 4, the slider 20 includes a slider body 21 having sleeves 22 on both left and right sides of the guide rail 3, and a pair of end caps attached to one end and the other end of the slider body 21 in the front-rear direction. 31, 31, a plurality of return guides 17 incorporated in these end caps 31, 31, and a pair of side seals 35, 35 for sealing gaps between the guide rail 3 and the end caps 31, 31. Prepare. Two slider-side rolling grooves (slider-side raceway surfaces) 10 facing the rail-side rolling grooves 5 of the guide rail 3 are formed in the sleeve portion 22 of the slider body 21 .

The slider body 21 has a slider side rolling groove 10 and a rolling element return path 28 . The slider-side rolling grooves 10 are formed on the inner side surfaces of both sleeves 22 of the slider body 21 and face the rail-side rolling grooves 5 . A rolling path 24 is formed. The rolling element return path 28 extends through the thick portions of both sleeves 22 in the axial direction of the guide rail 3 . Further, the upper surface of the slider body 21 is provided with a screw hole 33 into which a bolt for fixing a driven body such as a table to the slider 20 is screwed.

The end caps 31 are joined to the front and rear ends of the slider body 21, respectively, as shown in FIG. The end cap 31 is, for example, an injection-molded product of a synthetic resin material, and is formed to have a substantially C-shaped cross section like the slider body 21 . In the left and right sleeve portions 30 of the end cap 31, a semi-disk-shaped concave portion 15 is formed in two upper and lower stages on the abutment end surface 31a facing the end surface 21a of the slider body 21, and a semi-disk-shaped upper and lower two stages are formed. A semi-cylindrical groove 16 is formed across the center of the recess 15 . A semi-cylindrical return guide 17 is fitted in the semi-cylindrical recessed groove 16 to form a semi-doughnut-shaped direction change path 29 .

The direction changing path 29 connects the load rolling path 24 and the rolling element return path 28 . is configured. In the rolling element rolling path 27, for example, a plurality of steel balls 34 as rolling elements are loaded. It circulates endlessly while rolling inside 27 .

Further, the end cap 31 is provided with a plurality of mounting screw insertion holes 25 , and guide projections 36 are provided on the periphery of the mounting screw insertion holes 25 . Insertion holes (not shown) are also formed at positions facing the guide protrusions 36 in the slider body 21 , and the guide protrusions 36 of the end cap 31 are fitted into the insertion holes of the slider body 21 . Therefore, the joining accuracy between the two is ensured. A mounting screw 26 is inserted through the mounting screw insertion hole 25 toward the slider body 21 , and the end cap 31 is fastened to the slider body 21 by the mounting screw 26 .

The guide rail 3 to which the slider 20 is attached is made of metal, and two rail-side rolling grooves (rail-side raceway surface) 5 are formed along the axial direction of the guide rail 3 on its left and right side surfaces 3b. The guide rail 3 has a plurality of rail mounting holes 4 penetrating in the height direction of the guide rail 3. As shown in FIG. A shaft accommodation portion 4a for accommodation and a countersunk portion 4b for accommodation of the head portion 62 of the bolt 6 are formed. The guide rail 3 is fixed to the mounting surface 7 by bolts 6 inserted into the rail mounting holes 4 . Further, a cap 41 is fitted to the counterbore portion 4b of the rail mounting hole 4 to close the opening.

(Cap for guide rail mounting hole of linear guide device)
The cap 41 according to the present embodiment includes a cap head portion 41a and an insertion portion 41b provided on one axial end surface of the cap head portion 41a and inserted into the counterbore portion 4b. The insertion portion 41b has a cylindrical shape, and as shown in FIGS. 6A and 6B, has a bellows structure that can be expanded and contracted in the axial direction. Also, the cap head 41a has an outer diameter corresponding to the hole diameter of the counterbore. Specifically, the outer diameter of the cap head portion 41a is formed to be larger than the inner diameter of the counterbore portion 4b. The other end surface of the cap head portion 41a in the axial direction, that is, the surface opposite to the surface on which the insertion portion 41b is provided, has a shape that rises gently toward the center.

When fixing the guide rail 3 to the mounting surface 7 , the bolt 6 is inserted into the rail mounting hole 4 and screwed into the mounting surface 7 . As a result, the head of the bolt 6 is locked by the counterbore 4b, and the guide rail 3 is fixed to the mounting surface 7. As shown in FIG. After that, with the insertion portion 41b extended, the cap 41 is inserted into the rail mounting hole 4 from the side of the insertion portion 41b, and the cap head 41a is hit with a hammer or the like to fit in, whereby the guide rail 3 is provided with the cap head 41a. The opening of the rail mounting hole 4 is closed without a step.

In this embodiment configured as described above, when the cap 41 is inserted into the rail mounting hole 4 with the insertion portion 41 b extended, the tip of the insertion portion 41 b first contacts the upper surface of the bolt 6 . After that, by further inserting the cap 41, the insertion portion 41b is contracted according to the distance between the cap head 41a and the bolt 6, and is fitted into the rail mounting hole 4 by hitting the cap head 41a with a hammer or the like. In this state, the axial length of the insertion portion 41b is fixed. In this way, the cap 41 can accommodate various depths of the countersunk portions 4b, and the cap head portion 41a is supported by the fixed insertion portion 41b with an optimum length. It is possible to prevent the cap 41 from sinking.

In this embodiment, the length of the insertion portion 41b is not particularly limited. It is sufficient that the tip of the insertion portion 41b contacts the upper surface of the bolt 6 before reaching the same height as the upper surface of the rail 3. Further, it is sufficient that the tip of the insertion portion 41b contacts the top surface of the bolt 6 before the insertion portion 41b reaches the most contracted state.

Further, in the present embodiment, the surface of the cap head portion 41a opposite to the surface on which the insertion portion 41b is provided has a shape that rises gently toward the center thereof. When the cap head 41a has such a shape, it is possible to suppress the deposition of foreign matter on the upper surface of the cap head 41a, and as a result, it is possible to maintain good running accuracy and stopping position accuracy of the slider. can be done.

Furthermore, in this embodiment, the cap head portion 41a has an outer diameter that provides an interference fit with respect to the hole diameter of the counterbore portion 4b. If the outer diameter of the cap head portion 41a is designed in this way, after the cap 41 is fitted into the counterbore portion 4b of the rail mounting hole 4, it will not come off easily and the slider can travel safely. can be done. However, in the present invention, the shape and outer diameter of the cap head portion 41a do not have to be as described above, and are not particularly limited as long as the same effect can be obtained.

As shown in FIG. 7, the top surface of the head 62 of the bolt 6 is formed with a hexagonal hole 62a into which a hexagonal wrench is inserted for screwing the bolt 6 onto the mounting surface. If the insertion portion 41b enters the hexagonal hole 62a, it becomes difficult to fix the insertion portion 41b at an optimum length. Therefore, if the outer diameter of the insertion portion 41b is made larger than the diameter S of the inscribed circle of the hexagonal hole 62a, the insertion of the insertion portion 41b into the hexagonal hole 62a can be prevented, and the cap 41 sinks. It is possible to obtain a high effect of preventing

The cap 41 can be formed, for example, by injection molding of synthetic resin. By forming the cap 41 from a flexible synthetic resin, it is possible to allow variations in radial dimension during manufacturing, and the manufacturing cost of the cap 41 can be reduced.

More specifically, as the material of the cap 41, it is preferable to use a material having excellent abrasion resistance. Thermoplastic elastomers can be used. Among these, it is preferable to use a polyamide-based plastic or a polyamide-based thermoplastic elastomer. Further, in consideration of heat resistance, a polyamide-based resin is preferable.

The cap 41 may be formed by integrally molding the cap head portion 41a and the insertion portion 41b, or by molding the cap head portion 41a and the insertion portion 41b as separate members and then bonding them together. can be anything. When both are formed as separate members, materials can be selected according to their respective functions.
For example, the cap head 41a is hit with a hammer or the like to fit the cap 41 into the countersunk portion 4b. Moreover, since the side seal 35 shown in FIG. 1 passes through the upper surface of the cap head portion 41a, it is preferable to use a material with high slidability.
Therefore, considering impact resistance and slidability, the cap head 41a is preferably made of polyamide-based plastic, and specifically, nylon 6 is preferably used.

It should be noted that the present invention is not limited to the examples illustrated in the above embodiments, and can be modified as appropriate without departing from the gist of the present invention.
For example, in each of the above-described embodiments, the case where the present invention is applied to a linear guide device using ball-shaped rolling elements was exemplified. You may apply this invention to.

REFERENCE SIGNS LIST 1 linear guide device 3 guide rail 4 rail mounting hole 4a shaft accommodating portion 4b counterbore 6 bolt 7 mounting surface 20 slider 21 slider body 31 end cap 34 ball (rolling element)
35 side seal 41 cap 41a cap head 41b insertion portion 61 shaft portion 62 bolt head

Claims (7)

A guide rail mounting hole cap that is fitted into a counterbore portion of a mounting hole of a guide rail constituting a linear guide device and closes the mounting hole into which a bolt is inserted,
a cap head having an outer diameter corresponding to the hole diameter of the counterbore;
an inserting portion provided on one axial end surface of the cap head portion and inserted into the countersunk portion;
The cap for the guide rail mounting hole of the linear guide device, wherein the insertion portion is cylindrical and has a bellows structure that expands and contracts in the axial direction. 2. The guide rail mounting hole cap for a linear guide device according to claim 1, wherein the other axial end face of said cap head has a shape that rises gently toward its center. 3. The guide rail mounting hole cap for a linear guide device according to claim 1, wherein said cap head has an outer diameter that provides an interference fit with respect to the hole diameter of said counterbore. 4. The guide rail mounting hole cap for a linear guide device according to claim 1, wherein an outer diameter of said insertion portion is larger than a diameter of an inscribed circle of a hexagonal hole in said bolt. A guide rail mounting hole cap for a linear guide device according to any one of claims 1 to 4, wherein said cap head and said insertion portion are integrally formed. The guide rail mounting hole cap for a linear guide device according to any one of claims 1 to 4, wherein the insertion portion configured as a separate member from the cap head is adhered to the cap head. . a guide rail that has a plurality of rail mounting holes through which bolts can be inserted, and that is attached to a mounting surface using the bolts;
A linear guide device comprising a slider mounted so as to straddle the guide rail and relatively movable in the axial direction with respect to the guide rail,
The rail mounting hole of the guide rail includes a shaft receiving portion that receives the shaft portion of the bolt and a countersunk portion that receives the head portion of the bolt,
The guide rail mounting hole cap of the linear guide device according to any one of claims 1 to 6 is fitted to the counterbore portion of the rail mounting hole, and the head of the bolt and the insertion portion are in contact with each other. A linear guide device.

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