JP2003314548A - Seal body for linear bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal for a linear bearing having a superior wear-resistant property and lasting sealing capability. <P>SOLUTION: The seal body for the linear bearing is arranged on a slider 2 having a linear motion on a guide rail 1 with a rolling body rolling groove 1a extending to an axial direction, and seals up a gap between the outer periphery of the guide rail and the inner periphery of the slider. The seal body is provided with a metallic body portion fixed on the slider, and a seal member formed by thermoplastic elastomer having a lip portion which is brought into contact with the guide rail. The metallic body portion and the seal member are bonded and fixed each other with the aid of rubber. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal structure for a linear motion bearing used in machine tools, industrial machines, measuring instruments and the like. 2. Description of the Related Art As shown in FIG.
It comprises a guide rail 1 extending in the axial direction, and a slider 2 linearly movably in the axial direction on the guide rail. A rolling element rolling groove 1 is provided on the outer peripheral surface of the guide rail.
a, and a load rolling element rolling groove facing the rolling element rolling groove (not shown) is provided inside the slider. A plurality of rolling elements are provided between the rolling element rolling grooves and the load rolling element rolling grooves, and a slider is attached to a guide rail via the rolling elements. A rolling element return path for circulating the rolling elements is formed inside the slider body 2a. On the inner surface of the end cap 2b attached to both end surfaces in the moving direction of the slider body 2a, there is provided a connecting path for connecting the load rolling element rolling groove and the rolling element return path. Thereby, the load rolling element rolling groove and the rolling element return path are connected, the rolling element circulates inside the slider body, and the slider 2 can smoothly move on the guide rail. And
The slider is provided with a seal body having a lip portion that slides on the guide rail so that dust and dust do not enter the slider when the slider slides along the guide rail. The seals include a side seal attached to the front and rear surfaces of the slider, a lower seal attached to the lower end surface of the slide, and an upper seal provided on the inner surface of the slider to seal the upper surface of the guide rail. Conventionally, in these seals, a rubber seal member having a lip that slides on a guide rail is integrally formed on a main body made of metal by vulcanization bonding. However, in the case of a seal member having a rubber lip portion as described above, the lip portion wears as it is used over a long period of time, and sufficient sealing performance can be ensured. There was a problem that it disappeared. In some cases, the seal member is made of a resin material such as a thermoplastic elastomer having good wear resistance. There has been a problem that the seal member made of the elastomer is peeled off from the metal main body due to the load due to the movement. Thus, as shown in FIG. 4, the sealing member 103a is held and integrated by a metal plate 103c, or as shown in FIG.
There is also a case where 3d is provided and engaged to be integrated. However, when the method of integrating without using these adhesives is not sufficiently fixed to the main body, the sealing member is turned up from the main body, the movement of the lip becomes large, and the sealing performance cannot be maintained. was there. It is an object of the present invention to provide a seal structure for a linear motion bearing which can solve such conventional disadvantages and can maintain good sealing performance for a long time. SUMMARY OF THE INVENTION In order to achieve the above object, a seal for a linear motion bearing according to the present invention is provided with a slider that linearly moves on a guide rail having a rolling element rolling groove extending in an axial direction. A seal member for a linear motion bearing, which seals a gap between an outer peripheral surface of the guide rail and an inner peripheral surface of the slider, wherein the metallic main body fixed to the slider and the guide rail are in contact with each other. A sealing member made of a thermoplastic elastomer having a lip portion, wherein the main body and the sealing member are bonded and fixed via rubber. Therefore, according to the present invention, it is possible to firmly adhere the elastomer seal portion and the metal main body portion by bonding and fixing via rubber. In addition, since rubber is interposed between the elastomer seal portion and the metal main body portion, the rubber layer absorbs deformation of the elastomer seal portion due to sliding with the guide rail,
An excessive load is not applied to the seal portion, and the seal life is improved. An embodiment of the present invention will be described below with reference to FIG.
Explanation will be made based on FIG. FIG. 1 is a perspective view of a linear motion bearing.
A guide rail 1 having a rolling element rolling groove 1a on its outer surface and extending in the axial direction, and a slider 2 mounted on the guide rail
And A side seal 3, which is one of the seal bodies, is screwed to the end cap 2b at both end surfaces in the moving direction of the slide. As shown in FIG. 2, a seal member 3a made of a thermoplastic elastomer is provided on the outer surface of a thin metal main body 3b having a substantially U-shape conforming to the outer shape of the end cap 2b via rubber, as shown in FIG. Is fixed. The seal member 3a is provided with a lip portion 3d that can slide on the upper surface and side surfaces of the guide rail according to the cross-sectional shape of the guide rail so as to seal the gap between the slider 2 and the guide rail 1. This seals the gap between the guide rail and the slider, thereby preventing dust from entering the slider. In the manufacture of the above-mentioned seal body, as shown in FIG. 3, a seal member 3a made of a thermoplastic elastomer formed in a predetermined shape in a lower mold 5 in advance and coated with an adhesive.
And a metal body 3b to which an adhesive has been applied is placed with the unvulcanized rubber 3c interposed therebetween, and then the upper mold is closed and compression molding is performed. By the compression molding, the unvulcanized rubber in the cavity is vulcanized and firmly adhered to the entire surface of the thermoplastic elastomer seal member and the metal main body. In the above manufacturing method, the rubber is bonded by vulcanization, but the bonding method is not limited thereto, and vulcanized rubber may be used. The thermoplastic elastomer used in the present invention comprises:
A polyester elastomer, a polyolefin-based elastomer, or the like can be used. Also, as rubber material,
Nitrile rubber or the like can be used. In addition, a phenol-based adhesive or the like can be used as the adhesive. Although the embodiment of the present invention is applied to a side seal, it is attached to a lower end surface of a slider,
Applied to the lower surface seal that seals the lower end of the slider and the side surface of the guide rail, and the upper surface seal that is provided on the inner surface of the slider facing the upper surface of the guide rail and covers the upper surface of the guide rail and prevents dust from entering the rolling elements May be. As is apparent from the above description, according to the seal member for a linear motion bearing of the present invention, the seal member is made of a thermoplastic elastomer having good wear resistance, so that the seal life is improved. . In addition, since the sealing member is strongly adhered and fixed to the entire outer peripheral surface of the main body, the sliding of the slider causes the sealing member to be turned up from the main body, thereby increasing the movement of the lip and deteriorating the sealing performance. There is no. Further, since the rubber layer absorbs the deformation of the elastomer seal member due to sliding with the guide rail, an excessive load is not applied to the seal member, and the seal life is improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a linear motion bearing. FIG. 2 is a view showing an example in which a seal body for a linear motion bearing of the present invention is applied to a side seal, and FIG. (B) is a sectional view. FIG. 3 is a view showing a method for manufacturing a seal member for a linear motion bearing of the present invention. FIG. 4 is a cross-sectional view showing a seal member for a conventional linear motion bearing. FIG. 5 is another seal member for a conventional linear motion bearing. [Description of reference numerals] 1 Guide rail 2 Slider 3 103 Side seal 3a 103a Seal member 3b 103b Main body 3c Rubber layer 103c Metal plate 3d 103d Lip 103e Uneven portion 4 Upper die 5 Lower die 6 Cavity

Claims (1)

Claims: 1. A slider which linearly moves on a guide rail having a rolling element rolling groove extending in an axial direction, wherein the slider has an outer peripheral surface and an inner peripheral surface of the slider. A seal body for a linear motion bearing that seals a gap between the main body, the seal body having a metal body fixed to the slider, and a seal member made of a thermoplastic elastomer having a lip portion in contact with a guide rail; A seal member for a linear motion bearing, wherein a portion and the seal member are bonded and fixed via rubber.