JPH09317764A - Structure of under seal support part of linear guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set a lip part of an under seal in such a state as making sliding contact with a side face of a guide rail at all times by providing a recessed part which supports an elastic projection of the under seal in the internal bottom part of an end cap and forming a face for receiving the projection into such a shape as enlarging its opening towards the guide rail side. SOLUTION: Longitudinal both ends of an under seal 3 are supported by being inserted into a recessed part 21 in the internal bottom part of an end cap 2B of a bearing. The bottom face 21a of the recessed part 21 is so formed as enlarging its opening towards a guide rail side 1. When the under seal 3 is inserted into the recessed part 21, an elastic projection 32e is elastically deformed so as to be pressedly contacted with the bottom face 21a and so the under seal 3 is easily fitted thereto. In assembling works at a customer's place, when an external force, which shifts the under seal 3 in the direction for separating from the guide rail 1, is applied on the under seal, a reaction is generated in a face fitted with the elastic projection 32e by inclination of the bottom face 21a so that the lip part 32c of the under seal 3 can be brought in sliding contact with the side face 1a of the guide rail 1 at all times.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear guide used for linear motion guide in machine tools, general industrial machines, production facilities for automobiles and home electric appliances, semiconductor manufacturing facilities, food manufacturing facilities, etc. The present invention relates to a structure of a support portion provided below a end cap of a bearing for supporting both longitudinal ends of an under seal that seals a guide rail from a lower side.

[0002]

2. Description of the Related Art A linear guide, for example, as shown in FIG. 1, has rolling element grooves 11 extending parallel to the longitudinal direction on both side surfaces 1a.
Bearing having a rolling element groove 21 that faces the rolling element groove 11 on both inner side surfaces 2a that are engaged so as to straddle the guide rail 1 and that are arranged opposite to the both side surfaces 1a. 2 and the rolling element groove 1
The bearing 2 slides along the guide rail 1 as the rolling element rolls on the rolling element rolling path formed by the reference numerals 1 and 21. The bearing 2 is composed of a main body 2A and end caps 2B fixed to both ends in the longitudinal direction, and a return path 2 provided on the outer surface 2b side inside the main body 2A.
2 and the curved path 23 provided in the end cap 2B,
A circulation path for rolling elements is formed.

An underseal 3 for sealing between the side surface 1a of the guide rail 1 and the inner side surface 2a of the bearing 2 from below is attached to such a linear guide. The underseal 3 is fixed to the lower surface of the bearing 2 with machine screws or rivets, or, for example, as disclosed in Japanese Utility Model Laid-Open No. 1-178221 filed earlier by the applicant of the present invention,
An underseal housing step 31 that is recessed from the lower surface on the outer surface 2b side is provided on the lower surface on the inner surface 2a side of the main body 2A, and a recess 21 is provided at a predetermined depth L ₀ on the lower inner surface of the end cap 2B (see FIG. 8 and 9), and by inserting both ends in the longitudinal direction of the underseal 3 into the underseal housing step 31, the underseal 3 is attached. The surface 21a of the recess 21 that receives the lower surface of the underseal 3 is formed horizontally.

Here, as shown in FIG. 10, both ends in the longitudinal direction (on the side opposite to the lip portion 3a slidably contacting the side surface of the guide rail) of the underseal 3 are attached to the end cap 2B. A disk-shaped elastic projection 3b is formed on the lower surface of the portion (inserted into the recess 21). Further, the thickness of the portion of the underseal 3 where the elastic protrusion 3b is formed is
It is larger than the vertical dimension of the recess 21. Therefore, the elastic protrusion 3b is pressed against the lower surface of the recess 21, and the elastic force supports the underseal 3. Thereby, the under seal 3 can be easily attached to the lower surface of the bearing 2 with almost one touch.

[0005]

However, in the above-described conventional underseal mounting structure, even if the lip portion of the underseal is adjusted so as to be in sliding contact with the side surface of the guide rail at the time of shipment, the assembly work or the like at the customer's side. When an external force is applied to the underseal at this time, the underseal may be displaced in the recess toward the side away from the guide rail, and a slight gap may be formed between the lip portion and the side surface of the guide rail.

The present invention has been made in view of such a conventional problem, and the both ends of the underseal are inserted into the recesses formed in the end cap of the bearing so that the underseal is attached to the lower surface of the bearing. In the under seal mounting structure of the linear guide to be mounted, even if external force is applied to the under seal at the customer's assembly work,
An object of the present invention is to prevent the underseal from slipping away from the guide rail in the recess so that the lip portion of the underseal is always in sliding contact with the side surface of the guide rail.

[0007]

In order to solve the above-mentioned problems, the present invention provides a recess for elastically deforming and supporting elastic projections at both ends in the longitudinal direction of an underseal at the lower part of the inner surface of an end cap of a linear guide bearing. In the structure of the underseal support portion, the surface of the recess for receiving the elastic projection is formed so as to be inclined so that the opening of the recess widens toward the guide rail side. The structure of the part is provided.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall front view of the linear guide device in which a half of the end cap is cut away.
Is a front view showing the inner surface of the end cap (the side to which the bearing body is joined), FIG. 3 is a view as seen from the arrow B in FIG. 2 (bottom view of the end cap), and FIG. 4 is used in this embodiment. FIG. 5 is a view showing a structure of an underseal (a view seen from a lower surface side of the linear guide at the time of mounting), and FIG.
It is an enlarged view of the A portion of FIG. In these figures, the description of the same parts as those of the above-mentioned conventional art will be omitted or simplified.

As shown in FIG. 1, in the main body 2A portion of the bearing 2, the underseal 3 is arranged in an underseal housing step portion 31 formed on the lower surface on the inner side surface 2a side over the entire length of the main body 2A. It Further, as shown in FIGS. 2, 3 and 5, both longitudinal ends of the underseal 3 are inserted into a recess 21 provided at a predetermined depth L ₀ below the inner surface of the end cap 2B of the bearing 2. Supported. In addition, in the portion where the concave portion 21 of the end cap 2B is formed,
A notch 24 corresponding to the structure of the underseal 3 used in this embodiment is provided.

As shown in FIG. 5, the recess 21 has a lower surface 21 for receiving the lower surface (elastic protrusion 32e) of the under seal 3.
a, a top surface 21b that receives the top surface of the underseal 3, and a bottom surface 21c that receives the end face in the longitudinal direction of the underseal 3, and in the linear guide assembled state, the top surface 21b is parallel to the horizontal plane and the bottom surface 21c is the vertical plane. In parallel, the lower surface 21a is formed such that the guide rail 1 side is an inclined surface that is lowered. That is, the lower surface 21 a of the recess 21 is formed so as to be inclined so that the opening of the recess 21 on the guide rail 1 side expands toward the guide rail side 1. In FIG. 5, the line C ₀ indicates the horizontal plane in the assembled state of the linear guide, and the line C ₁ along the lower surface 21a is inclined to the side where the guide rail 1 side is lowered from the horizontal plane in the assembled state of the linear guide.

As shown in FIGS. 1, 4, and 5, the underseal 3 used here has an overall length slightly longer than the length of the bearing body 2A and a width slightly less than the width of the underseal housing step 31. It is widely formed and is composed of a mandrel 31 and an elastic body 32 made of rubber or plastic and joined to the mandrel 31 by means such as integral molding.

The mandrel 31 of the underseal 3 has a base 31a that abuts on the upper surface 21b of the recess 21 at both ends in the longitudinal direction, and a base 31a that abuts the underseal housing step 31 of the main body 2A at other portions. It has a bent outer edge 31b.

The elastic body 32 of the underseal 3 is made of a mandrel 31.
A thick wall portion 32a that wraps the outer edge 31b of the core and the base portion 3 of the mandrel 31
A thin portion 32b that covers one surface (lower surface) of 1a, and a lip portion 32c that is in sliding contact with the side surface 1a of the guide rail 1 is formed at the tip of the thick portion 32a. Also, the thick portion 32a
By providing a cutout portion 32d over the entire length in the longitudinal direction on the lower surface of the above, and increasing the elastic deformation margin of the lip portion 32c, the sealing performance is improved.

On the lower surface of the thin portion 32b, disk-shaped elastic protrusions 32e are formed at both ends in the longitudinal direction (portions to be inserted into the recesses 21). The thickness of the portion of the underseal 3 where the elastic protrusion 32e is formed is, for example, not less than the vertical dimension L _{2 at} the point D on the opening side of the lower surface 21a formed as a slope in the recess 21 of the end cap 2B. It is dimensioned.

Further, the longitudinal ends of the elastic body 32 are made longer on the thick portion 32a side than on the thin portion 32b side, and the tip portions 32f are engaged with the cut portions 24 of the end cap 2B. It FIG. 6 is a bottom view of the linear guide showing the difference in the mounting state between the underseal 3 of this embodiment and the conventional underseal 30 (underseal of FIG. 10). The end seal 2C is formed longer than the conventional under seal 30 by the length of the tip portions 32f at both ends in the longitudinal direction, and the side seals 2C are arranged on the end faces of the tip portion 21f.
Over the entire length between the end faces of the
But) it is in contact with the guide rail 1. That is, in the conventional structure, the under seal 30 is provided at the end E on the side seal 2C side of the end cap 20B (end cap in FIG. 8).
Is not disposed, the structure of the underseal 3 and the end cap 2B of this embodiment provides higher sealing performance.

With this arrangement, in this embodiment, by inserting both longitudinal ends of the underseal 3 into the recess 21 of the end cap 2B, the elastic projection 32e is elastically deformed and pressed against the lower surface 21a of the recess 21. Therefore, the under seal 3 can be easily attached to the lower surface of the bearing 2 with almost one touch.

Further, even when an external force for shifting the underseal 3 to the side away from the guide rail 1 is applied at the time of assembling work at the customer's place, due to the inclination of the lower surface 21a of the recess 21, a reaction force against it is generated. Since the under seal 3 is formed on the fitting surface with the elastic protrusion 32e, the under seal 3 does not shift away from the guide rail 1 side, and the lip portion 32c of the under seal 3 can always be slidably contacted with the side surface 1a of the guide rail 1. it can. Furthermore, since the end cap 2B is a plastic injection-molded product, and the lower surface 21a of the recess 21 is inclined outward (the guide rail 1 side is lowered),
The recess 21 is easily released from the mold, and the moldability of the end cap 2B is improved.

In the above embodiment, the underseal 3
Since the elastic projection 32e is formed on the lower surface of the end cap 2B, the lower surface 21a of the recessed portion 21 of the end cap 2B is an inclined surface on which the guide rail 1 side is lowered, but as shown in FIG.
When 2e is formed on the upper surface of the underseal 3, the same effect as described above can be obtained by forming the upper surface 21b of the recessed portion 21 into an inclined surface that raises the guide rail 1 side.

Further, in the above embodiment, the underseal 3
The elastic protrusion 32e of the thick portion 32 including the lip portion 32c.
Although it is formed integrally with a and the thin portion 32b, it is not necessarily required to be integrally formed, and the elastic protrusion 32e may be directly fixed to the mandrel 31.

In the above embodiment, the underseal 3
The elastic projection 32e is formed in a disk shape, that is, the lower surface thereof is formed into a horizontal flat surface, but the lower surface shape of the elastic projection 32e is not limited to this and may be inclined.

The linear guide to which the present invention is applied is not limited to the one having two rows of rolling element grooves on one side as described above, and the rolling elements may be balls or rollers. .

[0022]

As described above, according to the present invention, both ends of the underseal are inserted into the recesses formed in the end cap of the bearing to attach the underseal to the lower surface of the bearing. In the structure, even if external force is applied to the underseal at the customer's assembly work, etc., the underseal does not separate from the guide rail in the recess, so the lip part of the underseal is always on the side of the guide rail. The sliding effect is ensured by the sliding contact with. As a result, it is possible to reliably reduce the amount of dust that enters the bearing, so that the rolling element rolling path is less damaged, the accuracy of the linear guide is prevented from deteriorating, and the running life is extended.

[Brief description of drawings]

FIG. 1 is a front view showing a linear guide device in which a half of an end cap is cut away.

FIG. 2 is a front view showing the inner surface (the side to which the bearing body is joined) of the end cap used in the embodiment.

FIG. 3 is a view from the arrow B of FIG. 2 (a bottom view of the end cap).

FIG. 4 is a view showing a structure of an underseal used in the embodiment (a view seen from a lower surface side of the linear guide at the time of mounting).

5 is a cross-sectional view showing the underseal in a state of being inserted into the recess of the end cap, and corresponds to an enlarged view of a portion A in FIG.

FIG. 6 is a bottom view of the linear guide showing the difference in mounting state between the underseal of this embodiment and the conventional underseal.

FIG. 7 is a cross-sectional view showing another embodiment of a recess.

FIG. 8 is a front view showing an inner surface (a side to which a bearing body is joined) of a conventional end cap.

9 is a view as seen from the direction of arrow B in FIG. 7 (a bottom view of the end cap).

FIG. 10 is a view showing a structure of a conventional underseal (a view seen from a surface which is a lower surface side of the linear guide at the time of mounting).

[Explanation of symbols]

 1 Guide rail 2 Bearing 2A Bearing body 2B Bearing end cap 3 Under seal 21 Recess 21a Lower surface (surface receiving elastic projection) 32e Elastic projection

Claims (1)

[Claims] 1. A structure of an underseal support portion, in which a recess for elastically deforming and supporting elastic projections at both ends in the longitudinal direction of an underseal is provided in a lower portion of an inner surface of an end cap of a linear guide bearing. A structure of an underseal support portion of a linear guide, characterized in that a surface for receiving the elastic projection is formed so as to be inclined so that an opening of the concave portion expands toward the guide rail side.