JP2016001056A - Seal protector and direct-acting guide device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seal protector capable of effectively preventing damage to an elastic lip portion of a direct-acting guide device.SOLUTION: A seal protector 42 comprises: a lip holding portion 42a provided in an edge of the seal protector 42 and holding an entire inner peripheral edge of a seal lip tip end portion 34 in a state in which the seal protector 42 is attached to a side seal 4 while separating the entire inner periphery from an outer peripheral surface of a rail 2; and an engagement flange portion 42b provided in the edge of the seal protector 42 and engaged with the outer peripheral edge of the side seal 4 by a predetermined elastic force. In a state in which the seal protector 42 is attached to the side seal 4, a clearance S2 is secured between a surface of the rail 2 and the lip holding portion 42a at a time of assembling a slider 3 into the rail 2.

Description

  The present invention relates to a seal protector used at the time of assembling a linear motion guide device, and relates to a technique for protecting a tip end of a seal lip of a side seal attached to an end cap of a slider from damage due to contact with a rail edge or the like. .

  In semiconductor manufacturing apparatuses and machine tools, a rail guide type linear motion guide device (linear motion guide device) is employed in order to realize a precise and smooth operation of a work holder, a machining head, and the like. This type of linear motion guide device includes a rail attached to a fixed side element (such as a machine base), a slider attached to a motion side element (such as a work holder), and a large number of rollers that are circulated in the slider. The moving body (roller or ball) is the main component.

  A plurality of rail-side tracks are formed along the longitudinal direction on the side surface of the rail, while a plurality of slider-side tracks are formed on the slider body constituting the slider so as to face the rail-side tracks. When moving, the rolling element rolls while contacting the rail-side track and the slider-side track. The slider body is provided with end caps for changing the moving direction of the rolling elements on the slider side track at both front and rear ends, and a return path for circulating the rolling elements.

  In a linear motion guide device incorporated in a mechanical device, it is inevitable that dust, cutting swarf, cutting fluid, etc. will adhere to the rail or end cap. Smooth rolling (that is, smooth movement of the slider) may be hindered. Therefore, in the linear motion guide device, a side seal is attached to the end face of the end cap, and the tip of the seal lip formed in accordance with the rail surface shape is brought into elastic contact with the surface of the rail, thereby preventing the above-mentioned entry of foreign matter. (See Patent Documents 1 and 2).

JP 2009-121648 A JP 2008-82504 A

  The side seal needs to have a tightening margin for the purpose of eliminating foreign matter by the elastic contact of the seal lip tip with the rail, and the inner shape of the seal lip tip in the free state (that is, the portion of the contact with the rail). (Shape) is set slightly smaller than the outer shape of the rail (that is, the cross-sectional shape of the contact portion with the seal lip tip). Therefore, when the slider is assembled to the rail, the seal lip tip of the side seal comes into contact with the edge of the rail, and the seal lip tip may be damaged, which may reduce the sealing performance (dustproof performance and liquid sealing performance). .

  In the linear motion guide device of Patent Document 1, the side seal has a folded plate-like or film-like seal member protector in order to prevent contact between the edge of the mounting hole that opens on the rail upper surface and the seal lip tip of the side seal. Is attached. However, since this seal member protector protects only the part of the side seal that corresponds to the rail mounting hole, when the slider is mounted on the rail, the tip of the seal lip is damaged by contact with the side end surface of the rail. There is a risk that it will take time and effort.

  On the other hand, in the linear motion guide device of Patent Document 2, the outer shape of the portion near the end surface of the temporary shaft is configured to gradually increase toward the end surface side, so that the temporary shaft and the rail are brought into linear contact with each other. When the sliders are lined up and transferred from the temporary shaft to the rail, the end portion is configured to push the seal lip end portion. However, when attaching the slider to the temporary shaft, there is also a risk that the work must be performed so that the tip of the seal lip is not damaged.

  The present invention has been made in view of the above situation, and provides a seal protector and a linear motion guide device that can prevent damage to the seal lip tip of the linear motion guide device.

The present invention for solving the above problems
Rails,
A slider which is guided by the rail and is movable on the rail;
A linear guide device comprising: a seal attached to the slider and having a seal lip tip contacting the rail;
A linear motion guide device comprising a seal protector that is detachably attached to the slider or the seal and that holds the seal lip tip portion away from the rail.

  In a preferred aspect of the present invention, the seal protector is attached to the seal so as to cover the surface of the seal.

The present invention for solving the above problems
Used in a linear guide device comprising a rail, a slider guided by the rail and movable on the rail, and a seal attached to the slider and having a seal lip tip contacting the rail;
A seal protector, which is detachably attached to the slider or the seal, holds the seal lip tip and holds the seal lip tip away from the rail.

  In a preferred embodiment of the present invention, the seal protector is attached to the seal so as to cover the surface of the seal.

  In a preferred aspect of the present invention, the seal protector includes a first half and a second half that are separable from each other.

  In a preferred aspect of the present invention, the seal protector includes a first part, a second part, and a third part that are separable from each other.

  ADVANTAGE OF THE INVENTION According to this invention, the seal protector which can prevent the damage of the seal lip front-end | tip part of a linear guide apparatus, and a linear guide apparatus can be provided.

It is a perspective view of the linear guide apparatus which concerns on 1st Embodiment. It is a principal part longitudinal cross-sectional view of the linear guide apparatus which concerns on 1st Embodiment. It is a perspective view of the slider which concerns on 1st Embodiment. It is a perspective view from the back of the seal protector which concerns on 1st Embodiment. It is a principal part longitudinal cross-sectional view of the linear guide apparatus which concerns on 1st Embodiment. It is a figure which shows the assembly procedure of the linear motion guide apparatus which concerns on 1st Embodiment. It is a perspective view of the slider which concerns on 2nd Embodiment. It is a perspective view from the back of the seal protector which concerns on 2nd Embodiment.

  Hereinafter, with reference to drawings, two embodiments of a seal protector of a linear motion guide device to which the present invention is applied will be described in detail. Although the linear motion guide device can be installed in any direction, for the sake of explanation, as shown in FIG.

<First Embodiment>
As shown in FIG. 1, the linear motion guide device 1 according to the first embodiment is attached to the rail 2 having a substantially rectangular cross section extending in the front-rear direction, and is movable in the front-rear direction while being guided by the rail 2. The main components are the slider 3 and side seals 4 respectively attached to the front and rear ends of the slider 3. The slider 3 is mainly composed of a slider main body 5, end caps 6 attached to the front and rear end surfaces of the slider main body 5, and a plurality of cylindrical rollers 25. Each end cap 6 is fastened to the slider body 5 by four screws 7 together with the side seal 4.

  The rail 2 has two upper and lower rail-side tracks 11 and 12 on the left and right side surfaces, and is fastened to the mounted portion by a hexagon socket head cap screw 14 fitted in the stepped bolt hole 13. In addition, a disc-shaped resin lid 15 is fitted into the stepped bolt hole 13 after fastening so as to flatten the upper surface of the rail 2.

  The slider body 5 has a substantially inverted U-shaped cross-section with an open bottom, and corresponds to the two upper and lower slider-side tracks 21 and 22 facing the rail-side tracks 11 and 12, and the slider-side tracks 21 and 22, respectively. Return paths 23 and 24. A large number of rollers 25 are interposed between the rail-side tracks 11, 12 and the slider-side tracks 21, 22, and when the slider 3 moves, the rollers 25 are moved to the rail-side tracks 11, 12 and the slider-side tracks 21, 22. Roll while contacting 22. The rollers 25 are also filled in bent paths (described later) and return paths 23 and 24 in the end cap 6.

  A plurality of bent paths (not shown) for changing the moving direction of the rollers 25 by 180 ° are formed in the end cap 6. When the slider 3 is moved, these bent paths and the return paths 23, 24 The rollers 25 are fed from one end of the slider side tracks 21 and 22 to the other end. A taper screw hole 28 into which a grease nipple (not shown) is screwed opens at the upper part of the end cap 6.

  As shown in FIG. 2, the side seal 4 has a seal lip 33 sandwiched between two seal holding plates 31 and a seal cover plate 32. The seal holding plate 31 and the seal cover plate 32 have substantially the same outer shape as the end cap 6 (that is, the shape of the upper and left and right sides), and the seal lip 33 has an inner shape similar to the outer shape of the rail 2. doing. As a material of the seal lip 33, a thermoplastic elastomer resin such as polyester or urethane, rubber such as nitrile rubber, fluorine rubber, acrylic rubber, or silicon rubber can be employed.

  The inner shape of the seal lip 33 in a free state is set slightly smaller than the outer shape of the rail 2, and as shown in FIG. 2, the rail 2 has a predetermined deflection allowance (tightening allowance) S1 at its inner peripheral end. A seal lip tip 34 is formed in sliding contact with the outer peripheral surface of the seal lip. The seal lip tip 34 has a shape in which the tip is recessed inward (that is, on the rail 2 side) toward the front.

  As shown in FIG. 1, a pair of left and right seal protectors 41, 42 are detachably attached to the front side seal 4 as a first half and a second half that are separable from each other. These seal protectors 41 and 42 are thin-walled injection-molded products made of resin. As shown in FIGS. 3 and 4, each of the seal protectors 41 and 42 has a shape that covers the left half and the right half of the side seal 4. Yes.

  As shown in FIGS. 3, 4, and 5, both seal protectors 41 and 42 keep the entire inner peripheral edge of the seal lip tip 34 away from the outer peripheral surface of the rail 2 while being attached to the side seal 4. The lip holding portions 41a and 42a that are held in a state where they are in contact with each other and the engaging flange portions 41b and 42b that are engaged with the outer peripheral edge of the side seal 4 with a predetermined elastic force are provided at the respective edge portions. Both the seal protectors 41 and 42 are provided with through holes 41c and 42c into which the heads of the screws 7 are fitted. Further, as shown in FIG. 5, when the seal protectors 41 and 42 are attached to the side seal 4, when the slider 3 is assembled to the rail 2, the surface of the rail 2 and the lip holding portions 41a and 42a are not connected. The gap S2 is secured.

  As materials for the seal protectors 41 and 42, polyacetal resin, polyamide resin, polyetherimide resin, polyetheretherketone resin, polyphenylene sulfide resin, polypropylene, polystyrene, polyethylene, and the like can be used, but polyacetal resin can be used. Desirable for the following reasons. That is, since the polyacetal resin has low hygroscopicity, the polyacetal resin hardly absorbs moisture (humidity) contained in the air around the slider 3 and expands. 34 can be prevented from being damaged. In addition, since the polyacetal resin has a high vibration absorption name, vibration generated when the seal protectors 41 and 42 are attached to the side seal 4 can be effectively absorbed.

  In assembling the linear motion guide device 1, an assembly operator or an assembly robot (hereinafter referred to as an assembly operator or the like) first attaches a seal protector 41 to the side seal 4 of the slider 3 as shown in FIG. 42 (only the seal protector 42 is shown in FIG. 6) is attached. At this time, the engaging flange portions 41 b and 42 b are placed on the outer peripheral edge of the side seal 4 while the inner end edge of the seal lip tip 34 is pushed outward by the lip holding portions 41 a and 42 a. In this state, since the engagement flange portions 41 b and 42 b are engaged with the outer peripheral edge of the side seal 4 with elasticity, it is possible to prevent the seal protectors 41 and 42 from being unintentionally detached from the side seal 4.

  Next, as shown in FIG. 6B, the assembly worker or the like completes the linear motion guide device 1 by assembling the slider 2 on the rail 2 from the rear end side. At this time, since the gap S2 is secured between the lip holding portions 41a, 42a of the seal protectors 41, 42 and the surface of the rail 2 (see FIG. 5), the lip holding portions 41a, 42a and the side seals 4 The seal lip tip 34 is not damaged by contact with the rail 2. Further, even after the slider 3 is assembled to the rail 2, the seal protectors 41 and 42 are attached until the linear motion guide device 1 is operated, so that the side seals are installed when the linear motion guide device 1 is installed. 4 can be prevented from being damaged by a tool or the like.

  When the linear motion guide device 1 is supplied to a machine assembly plant or the like, the rail 2 is fastened to the mounted portion, and the lid 15 is fitted into the stepped bolt hole 13 (see FIG. 1), the assembly operator or the like As shown in (c), the left and right seal protectors 41 and 42 are removed from the side seal 4. Then, since the lip holding portions 41a and 42a do not exist, the seal lip tip portion 34 of the side seal 4 comes into close contact with the surface of the rail 2 by elasticity, and the desired sealing performance is exhibited. In the first embodiment, since the seal protectors 41 and 42 divided into the left and right are employed, the seal protectors 41 and 42 can be easily detached from the side seal 4 even when the rail 2 is present.

Second Embodiment
Also in the second embodiment, the configuration of the linear motion guide device 1 is the same as that of the first embodiment. However, as shown in FIGS. 7 and 8, as the seal protector, the first part, the second part, and The seal protectors 51 to 53 (the center seal protector 51 and the left and right seal protectors 52, 53) divided into three parts in the third portion are attached to the side seal 4.

  The center seal protector 51 has a substantially rectangular shape when viewed from the front, has a lip holding portion 51 a corresponding to the upper surface of the rail 2 at the lower edge, and engages with the upper edge of the side seal 4. 51b at the upper edge. The central seal protector 51 is provided with semicircular cutouts 51c that engage with the heads of the screws 7 at the left and right ends.

  On the other hand, the left and right seal protectors 52, 53 have lip holding portions 52 a, 53 a corresponding to the side surfaces of the rail 2 at the inner edge, and engaging flange portions 52 b, 53 b that engage with the side edges of the side seal 4. On the outer edge. The left and right seal protectors 52 and 53 are provided with through holes 52c and 53c into which the heads of the screws 7 are fitted.

  Although the operation of the second embodiment is substantially the same as that of the first embodiment described above, since the seal protectors 51 to 53 divided into three are adopted as the seal protectors, the linear motion guide device 1 is used as a machine base or the like. It becomes easier to remove the seal protectors 51 to 53 after being fastened.

  This is the end of the description of specific embodiments. However, aspects of the present invention are not limited to these embodiments. For example, in the above embodiment, the present invention is applied to a seal protector for a linear motion guide device using rollers as rolling elements. However, the present invention is applicable to a seal protector for a linear motion guide device using a ball, Of course, the present invention can also be applied to seal protectors of other types of linear motion guide devices such as splines. In addition, the specific structure of the linear motion guide device and the specific shape of the seal protector can be changed as appropriate without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Linear motion guide apparatus 2 Rail 3 Slider 4 Side seal 5 Slider main body 6 End cap 7 Screw 11, 12 Rail side track 13 Bolt hole 14 Bolt 21, 22 Slider side track 23, 24 Return path 25 Roller 31 Seal holding plate 32 Seal Cover plate 33 Seal lip 34 Seal lip tip 41, 42 Seal protector 41a, 42a Lip holding part 41b, 42b Engagement flange 41c, 42c Through hole
51-53 Seal protector 51a-53a Lip holding part 51b-53b Engagement flange part 51c Notch 52c, 53c Through-hole

Claims (6)

Rails,
A slider which is guided by the rail and is movable on the rail;
A linear guide device comprising: a seal attached to the slider and having a seal lip tip contacting the rail;
A linear motion guide device comprising a seal protector which is detachably attached to the slider or the seal, and holds the seal lip tip portion away from the rail.   The linear motion guide device according to claim 1, wherein the seal protector is attached to the seal so as to cover a surface of the seal. Used in a linear guide device comprising a rail, a slider guided by the rail and movable on the rail, and a seal attached to the slider and having a seal lip tip contacting the rail;
A seal protector which is detachably attached to the slider or the seal, holds the seal lip tip, and holds the seal lip tip away from the rail.   The seal protector according to claim 3, wherein the seal protector is attached to the seal so as to cover a surface of the seal.   The seal protector according to claim 3 or 4, comprising a first half and a second half that are separable from each other.   The seal protector according to any one of claims 3 to 5, comprising a first part, a second part, and a third part that are separable from each other.

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