JP2004360824A - Linear guide bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a linear guide bearing device capable of securing the smooth circulation of rollers by performing the positioning of a circulating tube and a direction changing passage, and the positioning of both rolling element rolling grooves and the direction changing passage with high accuracy, and miniaturizing the device. <P>SOLUTION: This linear guide bearing device is provided with a clearance 7a between an outer peripheral face of the circulating tube 8 inserted into a hole 7 of a slider main body 2A and an inner peripheral face of the hole 7, both ends of the circulating tube 8 are supported by end caps 9 fixed to an end face of the slider main body 2A, and the circulating tube 8 has a length approximately same as the slider main body 2A. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a linear guide bearing device used in, for example, the field of machine tools and industrial machines.
[0002]
[Prior art]
As a conventional linear guide bearing of this type, for example, the one shown in FIG. 8 is known.
This linear guide bearing device includes a guide rail 1 extending in the axial direction, and a slider 2 laid on the guide rail 1 so as to be relatively movable in the axial direction.
Rolling element rolling grooves 3 extending in the axial direction are formed on both side surfaces in the width direction of the guide rail 1, each having four rows of upper and lower two rows on one side, and both sleeves are provided on the slider body 2 </ b> A of the slider 2. A rolling element rolling groove 5 facing the rolling element rolling groove 3 is formed on the inner surface of the portion 4.
[0003]
A large number of rollers 6 as rolling elements are rotatably mounted between the two rolling element rolling grooves 3 and 5, and the slider 2 is axially moved on the guide rail 1 through the rolling of these rollers 6. It can move relatively along.
With this movement, the roller 6 interposed between the guide rail 1 and the slider 2 rolls and moves to the axial end of the slider 2, but in order to continuously move the slider 2 in the axial direction, It is necessary to circulate these rollers 6 infinitely.
[0004]
For this reason, two upper and lower (total four) holes 7 penetrating in the axial direction are respectively formed in the sleeve portions 4 on both sides of the slider main body 2A, and the inside of the hole 7 has a roller 6 passage (rolling member passage). 8a, and a pair of end caps 9 as rolling element circulating parts are fixed to both ends of the slider body 2A in the axial direction via screws or the like. By forming a semicircularly curved turning path 9a (see FIGS. 3 and 4) communicating between the rolling element rolling grooves 3 and 5 and the rolling element passage 8a, an endless circulation track of the rollers 6 is formed. are doing.
[0005]
The direction change path 9a provided in the end cap 9 connects the upper rolling element passage 8a with the lower rolling element rolling grooves 3 and 5, and the lower rolling element path 8a. The one that communicates between the upper rolling element rolling grooves 3 and 5 is formed to intersect so as not to interfere with each other.
By the way, when the end cap 9 is fixed to the end face of the slider body 2A, the positioning of the circulation tube 8 (the rolling element passage 8a) and the direction changing path 9a, and the two rolling element rolling grooves 3, 5 and the direction changing path are used. Positioning with the roller 9a is important for ensuring smooth circulation of the rollers 6.
[0006]
As a technique related to such positioning, for example, a cutout is formed at both ends of a sleeve (circulation tube), and the cutout of the sleeve is aligned with the open end of the direction change path of the side plate (end cap). The casing, the sleeve, and the side plate are positioned with respect to each other by forming the convex part, and fitting the convex part into the circular hole (insertion hole of the circulation tube) of the casing (slider body) and the notched part of the sleeve. Such a configuration has been proposed (for example, see Patent Document 1).
[0007]
Also, a gap is provided between the wall surface of the return hole (insertion hole of the circulation tube) provided in the casing (slider body) and the outer surface of the sleeve (circulation tube), and both ends of the sleeve are turned in the direction formed by the end cap. Japanese Patent Application Laid-Open Publication No. H11-163,087 proposes a method in which a sleeve is fitted into a fitting groove connected to a road, thereby fixing and positioning a sleeve on an end cap.
[0008]
[Patent Document 1]
Japanese Patent No. 2865854 [Patent Document 2]
JP-A-9-72335
[Problems to be solved by the invention]
However, in the above-mentioned Patent Document 1, the circular hole provided in the casing is longer than the diameter, so that a processing error is apt to occur. Further, in consideration of the workability, the processing of the circular hole is usually performed before the heat treatment. However, since the casing has a vertically asymmetric shape, deformation occurs due to the heat treatment, and therefore, an error occurs in the positional accuracy between the circular hole and the rolling surface (rolling element rolling groove) on which finishing processing is performed after the heat treatment.
[0010]
In this case, it is difficult to correct the deformation in advance because the manner of deformation of the casing due to the heat treatment varies depending on the history of the material and the lot of the heat treatment. Therefore, if the positions of the sleeve and the side plate are determined with reference to the circular hole provided in the casing, a deviation occurs at the connecting portion between the rolling surface on the casing side and the direction changing path on the end cap side, and smooth circulation of the rollers is hindered. There is a possibility that it will be.
[0011]
On the other hand, in Patent Document 2, since a gap is provided between the wall surface of the return hole provided in the casing and the outer surface of the sleeve, the above-described problem does not occur, but the end of the circulation tube is fitted. Since the direction changing path of the end cap is formed outside in the axial direction by the depth of the fitting groove, the axial length of the device is increased.
The present invention has been made in order to solve such inconvenience, and it is possible to accurately perform the positioning between the circulation tube and the direction change path and the positioning between the two rolling element rolling grooves and the direction change path. It is an object of the present invention to provide a linear motion guide bearing device capable of ensuring smooth circulation of rollers and reducing the size of the device.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 includes a guide rail having a rolling element rolling groove extending in an axial direction, and a rolling element rolling groove opposed to the rolling element rolling groove of the guide rail. And a slider straddling the guide rail so as to be relatively movable along the axial direction through the rolling of a number of rollers as rolling elements inserted between these rolling elements rolling grooves. ,
The slider is a slider body having a circulation tube which is inserted into a hole penetrating in the axial direction and forms a rolling element passage therein, and a curved body which communicates between the rolling element rolling grooves and the rolling element path. A linear guide bearing device comprising: a pair of end caps having a direction change path and fixed to both axial end surfaces of the slider body;
A gap is provided between the outer peripheral surface of the circulation tube and the inner peripheral surface of the hole, both ends of the circulation tube are supported by the end caps, and the circulation tube has substantially the same length as the slider body. It is characterized by.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view for explaining a main part of a linear motion guide bearing device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is a main part of an end cap. FIG. 4 is a cross-sectional view taken along the line BB of FIG. 3, FIG. 5 is a diagram for explaining an example in which a support portion is provided at the center in the longitudinal direction of the circulation tube, and FIG. 6 is a diagram of FIG. FIG. 7 is a cross-sectional view taken along line CC, and FIG. 7 is a cross-sectional view illustrating a modified example of the support portion. In this embodiment, the same parts as those of the conventional linear guide bearing device already described with reference to FIG.
[0014]
As shown in FIG. 1, in a linear motion guide bearing device 10 according to an embodiment of the present invention, a resin circulation tube 8 is inserted into four holes 7 penetrating through a slider body 2A. A rolling element passage 8a having a rectangular cross section through which the rollers 6 can pass with some clearance is formed in the inner peripheral portion of the tube 8. The circulation tube 8 is in a state in which half-shaped tubes are joined in the radial direction. The length of the circulation tube 8 is substantially the same as the length of the slider body 2A, and convex portions 14 are provided at both ends in the longitudinal direction. Further, as shown in FIG. 2, a gap 7 a is provided between the outer peripheral surface of the circulation tube 8 and the inner peripheral surface of the hole 7.
[0015]
A holding member 11 for holding the upper and lower rollers 6 is interposed between the upper rolling element rolling grooves 3 and 5 and the lower rolling element rolling grooves 3 and 5. A positioning groove 12 for the end cap 9 is provided at the axial end.
As shown in FIGS. 3 and 4, the end cap 9 is provided with a concave portion 15 around the open end of the direction change path 9 a, in which the convex portion 14 of the circulation tube 8 is engaged. On a surface facing the main body 2A side, a positioning projection 13 fitted into the positioning groove 12 is provided so as to protrude.
[0016]
The direction changing path 9a connects the upper rolling element passage 8a with the lower rolling element rolling grooves 3 and 5, and the direction changing path 9a communicates with the lower rolling element path 8a and the upper rolling element rolling paths. Those communicating with the moving grooves 3 and 5 are formed so as to cross three-dimensionally so as not to interfere with each other.
Then, the positioning protrusion 13 of the end cap 9 is fitted into the positioning groove 12 on one end face of the slider body 2A, and in this state, the circulation tube 8 is inserted into the hole 7 from the other end face of the slider body 2A, By engaging the convex portion 14 at one end of the tube 8 with the concave portion 15 on the end cap 9 side, the circulation tube 8 is supported with a gap 7a provided between the circulation tube 8 and the hole 7. I have to.
[0017]
Thereby, the positioning of the rolling element passage 8a in the circulation tube 8 and the direction change passage 9a on the outer side on the end cap 9 side can be accurately performed, and the outer peripheral surface of the circulation tube 8 and the inner periphery of the hole 7 can be accurately adjusted. Since the gap 7a is provided between the end face of the slider body 2A and the end face of the slider body 2A without being affected by the positional accuracy error between the hole 7 and the rolling element rolling groove 5 due to processing of the hole 7 or heat treatment. The cap 9 can be attached, and the positioning between the direction changing path 9a on the inner side of the end cap 9 and the rolling grooves 3 and 5 can be accurately performed.
[0018]
As a result, smooth circulation of the rollers 6 can be ensured, and the operability of the device can be improved.
Further, since the length of the circulation tube 8 is substantially the same as the length of the slider body 2A, the opening end of the direction changing path 9a can be located on the end surface of the end cap 9 on the slider body 2A side. The thickness of the end cap 9 in the axial direction and the axial length of the slider 2 are reduced, so that the apparatus can be made compact.
[0019]
Note that the linear motion guide bearing device of the present invention is not limited to the above embodiment, and can be appropriately changed without departing from the gist of the present invention.
For example, if the axial length of the slider body 2A is increased, the central portion of the circulation tube 8 is likely to oscillate in a structure in which both ends of the circulation tube 8 are only supported by the end caps 9, and the vibration may generate sound, It is conceivable that abrasion occurs due to the rubbing of the rollers 6 or the smooth circulation of the rollers 6 is hindered.
[0020]
Assuming such a case, as shown in FIGS. 5 and 6, by providing the support portion 20 at a substantially central portion in the longitudinal direction of the circulation tube 8, the swing of the central portion of the circulation tube 8 is suppressed. You may do so. In addition, by disposing the support portion 20 at a substantially central portion in the longitudinal direction of the circulation tube 8, it is possible to prevent the position of the circulation tube 8 from being affected by the positioning with the end cap 9 at both ends. The support portion 20 need not be limited to one location as long as it is located substantially at the center of the circulation tube 8, and may be provided at a plurality of locations. Although the support portion 20 suppresses the run-out of the circulation tube 8, it is desirable that the positioning of the circulation tube 8 and the end cap 9 is not so affected. Therefore, the outer peripheral shape of the support portion 20 is tapered or rounded. A shape (see FIG. 7) is more desirable.
[0021]
【The invention's effect】
As is apparent from the above description, according to the present invention, the positioning of the circulation tube and the direction change path, and the positioning of both rolling element rolling grooves and the direction change path can be performed with high accuracy. Smooth circulation can be ensured, and the opening end of the direction change path can be located on the end surface of the end cap on the slider body side, so that the axial thickness of the end cap and, consequently, the axial length of the slider And the size of the apparatus can be reduced.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram for describing a main part of a linear motion guide bearing device that is an example of an embodiment of the present invention.
FIG. 2 is a sectional view taken along line AA of FIG.
FIG. 3 is an explanatory diagram for explaining a main part of an end cap.
FIG. 4 is a sectional view taken along line BB of FIG. 3;
FIG. 5 is a view for explaining an example in which a support portion is provided at the center in the longitudinal direction of the circulation tube.
FIG. 6 is a sectional view taken along line CC of FIG. 5;
FIG. 7 is a cross-sectional view showing a modification of the support section.
FIG. 8 is a partially cutaway view of an end cap for explaining a conventional linear guide bearing device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Guide rail 2 ... Slider 2A ... Slider main body 3 ... Rolling element rolling groove (guide rail side)
5. Rolling element rolling groove (slider body side)
6 Roller 7 Hole 7a Clearance 8 Circulating tube 8a Rolling element passage 9 End cap 9a Direction changing path 10 Linear guide bearing device

Claims (1)

A guide rail having a rolling element rolling groove extending in the axial direction; and a rolling element rolling groove opposed to the rolling element rolling groove of the guide rail, which is inserted between the two rolling element rolling grooves. A slider laid on the guide rail so as to be relatively movable along the axial direction through the rolling of a number of rollers as rolling elements,
The slider is a slider body having a circulation tube which is inserted into a hole penetrating in the axial direction and forms a rolling element passage therein, and a curved body which communicates between the rolling element rolling grooves and the rolling element path. A linear guide bearing device comprising: a pair of end caps having a direction change path and fixed to both axial end surfaces of the slider body;
A gap is provided between the outer peripheral surface of the circulation tube and the inner peripheral surface of the hole, both ends of the circulation tube are supported by the end caps, and the circulation tube has substantially the same length as the slider body. A linear motion guide bearing device.

Images