JP2002021849A - Linear movement guide bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely and easily realize the improvement of the operability and the reduction of the noise at a low cost without receiving the influence to a difference to be generated between the fine movement quantity dx1 of a steel ball from a load side to a non-load side and the fine movement quantity of the steel ball to be finely moved from the non-load side to the load side in response to the fine movement quantity dx1. SOLUTION: This direct driven type guide bearing device is provided with a guide rail 1 extended in the axial direction and having rolling body rolling grooves 3 extended in the axial direction in both sides thereof, and a slider 2 having a rolling body rolling groove opposite to the rolling body rolling grooves of the guide rail 1 and supported by the guide rail 1 freely to be moved along the axial direction through the rolling movement of multiple rolling bodies inserted in the rolling body rolling grooves and having a rolling body endless circulating track for endlessly circulating the rolling body and provided with a holding piece interposed between each rolling body adjacent to each other in the circulating direction. A rigidity value of the holding piece is set at 0.053 N/μm or more and at 0.175 N/μm or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear guide bearing device provided with a slider in which a holding piece is interposed between rolling elements adjacent to each other in a circulation direction.

[0002]

2. Description of the Related Art As a conventional linear guide bearing device of this type, as shown in FIG. 6, for example, a guide rail 1 extending long in an axial direction and a slider 2 movably straddled thereon are provided.
And those with Rolling member rolling grooves 3 extending in the axial direction are formed on both side surfaces of the guide rail 1, and rolling member rolling grooves are formed on inner surfaces of both sleeve portions 4 of the slider body 2 </ b> A of the slider 2. The rolling element rolling groove (not shown) facing the rolling element 3 is formed.

[0003] A large number of steel balls B as rolling elements are rotatably mounted between the rolling grooves of the rolling elements facing each other, and the slider 2 is guided by the rolling of the steel balls B. It can move on the rail 1 along the axial direction. With this movement, the steel ball B interposed between the guide rail 1 and the slider 2 rolls and moves to the end of the slider body 2A of the slider 2, but the slider 2 is continuously moved in the axial direction. In order to move, it is necessary to circulate these steel balls B infinitely.

Therefore, a linear rolling element passage (not shown) penetrating in the axial direction is further formed in the sleeve portion 4 of the slider body 2A, and end caps 5 are provided at both front and rear ends of the slider body 2A. The end cap 5 is formed with a rolling element circulation R portion 6 (see FIG. 7) which is curved in a semi-circular shape and connects the rolling element rolling grooves and the linear rolling element passages, so that the rolling element endless circulation. The orbit 7 is constituted.

Further, between the steel balls B adjacent to each other on the rolling element endless circulating track 7, as shown in FIG. 7, holding pieces 9 each having a concave surface 8 on both sides facing the steel balls B are provided. It is interposed so as to contact the steel ball B at the concave surface 8. Among them, in Japanese Patent Publication No. 4-27405, aiming at improvement of the operability, a plurality of elastic holding pieces are interposed in the rolling element row to thereby produce a circumferential direction generated in the rolling element row. In order to obtain an optimal tight state in the rolling element row, in Japanese Patent Application Laid-Open No. 5-126148, one of the holding pieces to be interposed in the rolling element row is described in Japanese Patent Application Laid-Open No. 5-126148. In addition, a structure of an adjustment holding piece used to make the pitch between rolling elements variable has been proposed, and describes a method of eliminating "gap" generated in a row of rolling elements and improving operability.

[0006]

In such a conventional linear guide bearing device, the above-mentioned rolling element endless circulating track is constituted by a plurality of parts. In order to absorb the variation in the diameter and obtain the optimum tightness in the rolling element row, a highly accurate and complicated holding piece specification (for example, a holding piece having an elastic part or a movable part) is required. It was required and its production was difficult. In addition, since one or a small number of holding pieces bear such specifications, the effect of improving the operability may not be sufficient.

If the variation in the track length exceeds the adjustment range of each holding piece, an excessively large compressive force is applied during the rolling element row, the operability is remarkably deteriorated, and further annoying noise is generated. There is a problem. In order to solve such a problem, the present applicant has previously proposed a linear motion guide bearing device in which a row of rolling elements and a row of holding pieces circulating infinitely are provided with a gap (Japanese Patent Application No. 11-14718). See specification).

However, this linear motion guide bearing device has
In addition, the rolling element endless circulation orbit 7 has a linear rolling element path.
The holding member is constituted by a curved rolling element circulation R portion 6.
The rigidity value of
From the straight rolling element passage on the side to the curved shape on the no-load side
Movement d of the steel ball that moves slightly to the rolling element circulation R part 6
x₁And the minute movement amount dx₁No load side corresponding to
The linear rolling which is on the load side from the curved rolling element circulation R portion 6
Small movement amount dx of steel ball that moves minutely to moving body passage _TwoBetween
The staggering of steel balls and changes in dynamic friction force occur.
The ball moves smoothly and revolves smoothly.
Operation) and further improve operability.
Is difficult.

[0009] The present invention has been made to solve such an inconvenience, a small amount of movement dx ₁ steel ball from the load side to the no-load side, the no-load side so as to correspond to the fine small movement amount dx ₁ without being affected by the difference occurring between the small movement amount dx ₂ of steel balls minutely moved to the load side from a straight capable of easily and realize improvement and noise reduction in operability at low cost It is an object to provide a dynamic guide bearing device.

[0010]

In order to achieve this object, a linear motion guide bearing device according to claim 1 has a rolling element rolling groove extending in the axial direction on both sides and is extended in the axial direction. A guide rail, and a rolling element rolling groove facing the rolling element rolling groove of the guide rail, and a shaft is formed through the rolling of a number of rolling elements inserted between these rolling element rolling grooves. A rolling piece is supported by the guide rail so as to be movable along the direction, and has a rolling element endless circulating track for circulating the rolling element infinitely, and a holding piece is interposed between the rolling elements adjacent to each other in the circulating direction. Wherein the rigidity value of the holding piece is not less than 0.053 N / μm and not more than 0.175 N / μm.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a graph showing the variation of the dynamic friction force of the linear guide device when four types of holding pieces having lower rigidity values are interposed between steel balls, and FIG. FIG. 3 is a graph showing the relationship between the size of the whisker component and the rigidity value of the holding piece, and FIG. 4 is a graph showing the movement distance of each holding piece having a different rigidity value. FIG. 5 is a graph showing the relationship between the rigidity of each holding piece and the amount of permanent deformation. In addition, the linear motion guide bearing device of this embodiment is different from the conventional linear motion guide bearing device shown in FIG. 6 in that the holding piece interposed between the steel balls adjacent to each other on the rolling element endless circulating track is different from the conventional linear motion guide bearing device. Only the differences will be described, and only the differences will be described.

That is, in the linear guide device of this embodiment, the rigidity value of the holding piece interposed between the steel balls B adjacent to each other on the rolling element endless circulation track 7 is 0.053 N /, which is lower than the conventional value. [mu] m or more 0.175 N / [mu] m was regulated to below by the holding piece of low rigidity, a small amount of movement dx ₁ steel ball from the load side to the no-load side, the fine small movement amount d
The difference (dx ₂ −dx) generated between the steel ball and the micro-movement amount dx ₂ that micro-move from the no-load side to the load side corresponding to x _1
1 ) is absorbed to prevent staggering of steel balls and fluctuations in dynamic frictional force, thereby improving operability and reducing noise at low cost and easily.

Here, the rigidity value means "the ratio of the change in the pitch between the rolling elements to the compressive force applied between the rolling elements" after the holding piece is interposed between the two rolling elements. That is, rigidity value (N / μm) = compression force (N) applied between rolling elements / change amount of pitch between rolling elements (μm). As means for restricting the rigidity value of the holding piece to 0.053 N / μm or more and 0.175 N / μm or less, a method of obtaining a required rigidity value by the structure of the holding piece itself or a required rigidity value by a material of the holding piece are obtained. There are methods and the like, but the latter is more convenient and preferred.
As a material of the holding piece having good moldability, excellent wear resistance, and a rigidity value of 0.053 N / μm or more and 0.175 N / μm or less, for example, soft polyethylene can be mentioned. In addition, it is possible to use elastomers, but in that case, it is important to select a material of a grade excellent in oil resistance, heat resistance and creep characteristics in addition to the above conditions,
Examples of such a material include perprene, more preferably, perprene S series and EN series (all are trade names manufactured by Toyobo Co., Ltd.).

Next, the rigidity value of the holding piece is set to 0.053N.
The grounds for setting the thickness to / 75 μm or more and 0.175 N / μm or less are described. FIGS. 1A to 1D show four types of holding pieces a to d having rigidity values lower than the conventional one (in order, the rigidity values are 0.05 and 0.0).
75, 0.1, 0.2 N / μm) is shown between the steel balls, the dynamic frictional force of the linear guide device varies, and FIG. 2 shows the conventional holding piece (stiffness value 2 N / μm). The dynamic friction force of the linear guide device interposed therebetween is shown as a variation, and FIG. 3 shows a whisker component as a measure of the operability based on the data of FIGS. 2) shows the relationship between the size of ()) and the rigidity value of the holding piece.

As is apparent from FIG. 3, the rigidity value is 0.1
At 75 N / μm or less, the size of the whisker component when the conventional holding piece is used is less than 1 N. Therefore, it can be seen that the operability is improved in the region where the rigidity value of the holding piece is 0.175 N / μm or less. From FIG. 3, it can be seen that the smaller the rigidity value of the holding piece, the higher the operability is. However, the smaller the rigidity value of the holding piece, the more the bending force in the circulation R portion and the repetitive force acting during rolling. The value of the amount of permanent deformation of the pitch between the rolling elements, that is, durability may be a problem.

FIG. 4 shows the relationship between the moving distance of each holding piece and the amount of deformation as an indicator of the durability of the holding pieces a to d. FIG. 5 shows the amount of permanent deformation and the amount of holding piece when the moving distance is about 125 km. This shows the relationship with the rigidity value. In a normal linear guide device with a holding piece, if a permanent deformation amount of 40 μm or more occurs, the clearance dimension of the steel ball row becomes too large, and the smooth revolution of the steel ball and the holding piece is hindered, and the durability is remarkably increased. descend. Therefore, from FIG.
It can be seen that a rigidity value of μm or more is required for the holding piece.

As described above, the rigidity of the holding piece is set to 0.05
3 N / μm or more and 0.175 N / μm or less. Since the holding pieces having the above-mentioned rigidity values are interposed between the rolling elements in this way, even if a compressive force acts on the rolling element row due to a variation in the track length due to a machining error of the parts or the like, the conventional holding piece can be used. It is possible to ensure the same level of operability and noise characteristics as the linear motion guide bearing device.

In applying the present invention, it is desirable to interpose the main holding piece between all the rolling elements. However, even if the main holding piece is not interposed at one place or a small number of places, The effect of improving the operability and noise characteristics is recognized as compared with the conventional product that does not use the holding piece. In this case, it is effective that the non-interposed portion of the main holding piece has a target shape when viewed from the rolling element row (so that the non-interposed portion is not continuous).

In the above embodiment, the case where one independent holding piece is interposed between the steel balls B is taken as an example. However, even when each holding piece is connected,
Needless to say, the same operation and effect can be obtained. Further, in the above-described embodiment, a cylindrical holding piece is used. However, the present invention is not limited to this. For example, a cylindrical holding piece may be used.

Further, in the above embodiment, the shape of the concave surface of the holding piece is an R shape having a curvature approximating the radius of the steel ball. However, the shape is not limited to this, and the shape of the concave surface may be a conical shape or a gothic arch shape. You may. Further, in the above-described embodiment, a steel ball is taken as an example of the rolling element. However, the present invention is not limited to this. For example, a ceramic ball may be used. .

[0021]

As is apparent from the above description, according to the present invention, the minute movement amount d of the steel ball from the load side to the no-load side.
and x _1, without being affected by the difference occurring between the small movement amount dx ₂ of steel balls minutely moves in correspondence with the fine small movement amount dx ₁ from the no-load side to the load side, the improvement of operability In addition, the effect that noise reduction can be easily realized at low cost can be obtained.

[Brief description of the drawings]

FIG. 1 is a graph showing fluctuations in dynamic frictional force of a linear guide device when four types of holding pieces having lower rigidity values are interposed between steel balls.

FIG. 2 is a graph showing a change in dynamic friction force of a conventional linear guide device in which a holding piece is interposed between steel balls.

FIG. 3 is a graph showing a relationship between a size of a mustache component and a rigidity value of a holding piece.

FIG. 4 is a graph illustrating a relationship between a moving distance and a deformation amount of each holding piece having a different rigidity value.

FIG. 5 is a graph showing the relationship between the rigidity value of each holding piece and the amount of permanent deformation.

FIG. 6 is an explanatory perspective view for explaining the entire configuration of the linear motion guide bearing device.

FIG. 7 is an explanatory diagram for explaining a conventional holding piece.

[Explanation of symbols]

 ad: holding piece 1: guide rail 2: slider 3: rolling element rolling groove 7: rolling element endless circulation path B: steel ball (rolling element)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shinichi Kasuga 78 Tobacho, Maebashi-shi, Gunma Nippon Seiko Co., Ltd. (72) Inventor Kenji 78 Tobacho, Maebashi-shi, Gunma Pref. Inventor Soichiro Kato 78 Toba-cho, Maebashi-shi, Gunma Nippon Seiko Co., Ltd. (72) Inventor Nobuaki Fujimura 78, Toba-cho, Maebashi-shi, Gunma Nippon Seiko Co., Ltd.F-term (reference) 3J101 AA02 AA33 AA44 AA52 AA64 AA71 BA10 BA13 BA20 EA02 EA32 EA41 FA01 FA60 3J104 AA03 AA23 AA36 AA65 AA69 AA74 AA76 BA01 CA02 CA11 CA14 DA02 DA20

Claims (1)

[Claims] An axially extending guide rail having rolling element rolling grooves extending in the axial direction on both side portions, and a rolling element rolling groove opposed to the rolling element rolling groove of the guide rail. And is supported by the guide rail so as to be movable in the axial direction through the rolling of a number of rolling elements inserted between these rolling element rolling grooves, and circulates the rolling elements infinitely. A linear guide bearing device comprising: a slider having a rolling element endless circulating path and a holding piece interposed between the rolling elements adjacent to each other in the circulating direction, wherein the rigidity value of the holding piece is 0.053 N / μm or more
A linear motion guide bearing device characterized by having a thickness of 175 N / μm or less.