JP2944797B2 - Linear motion rolling guide unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a rail having track grooves formed on both side walls in the longitudinal direction and a casing having track grooves corresponding to the track grooves. The present invention relates to a linear motion rolling guide unit configured to be fitted and slidable.

[0002]

2. Description of the Related Art Conventionally, various types of linear motion rolling guide units have been developed to hold a rolling element in a load area, that is, a raceway groove, and have exerted a certain effect. When the rolling element is a ball, the guide unit is a cage having a structure in which a slit slightly smaller than the diameter of the ball is formed in the plate-shaped member and the ball is held by the slit.

Further, a linear motion rolling guide unit as shown in FIG. 6 is disclosed. FIG. 6 is a perspective view showing an example of a conventional linear motion rolling guide unit. As shown in FIG. 6, the linear motion rolling guide unit mainly comprises a rail 1 having a track groove 9 formed on both longitudinal side walls 11 and the rail 1.
It comprises a slide unit 20 slidably attached over the upper part. The slide unit 20
A plurality of rollers which are relatively slidable with respect to the rail 1 and have a track groove 8 formed at a position facing each track groove 9 and which can be relatively moved by fitting between the opposed track grooves 8, 9. The ball 4 as a moving body and the end caps 5 attached to both ends of the casing 2 in the sliding direction, that is, in the longitudinal direction, are provided. A side seal member 19 for achieving a seal between the rail 1 and the slide unit 20 is attached to the end cap 5, and a grease nipple 18 for supplying a lubricant to a sliding surface between the rail 1 and the slide unit 20. Is attached. Further, in order to prevent the balls 4 from dropping from the casing 2, a holding band 17 is attached to the casing 2 so as to surround a large number of balls 4. Also, while ensuring that the balls 4 do not fall off the casing 2, the casing 2 and the rail 1
The holding plate 3 is attached to the casing 2 in order to seal the longitudinal side walls 11 and the lower surface of the casing 2.

The slide unit 20 is mounted so as to straddle the rail 1 and slides freely with the interposition of a rolling element 4 composed of a plurality of balls circulating along the track groove 9 of the rail 1. is there. That is, the rolling elements 4 in the load area running in the raceway grooves 9 of the rail 1 are guided to a later-described turning path 25 formed in the end cap 5, and are formed above the casing 2 in parallel with the raceway grooves 8. Then, the rolling elements 4 move to the return passage hole 36 thus circulated infinitely in the endless circulation path. As described above, the rolling movement of the loaded ball 4 located between the raceway groove 8 formed in the slide unit 20 and the raceway groove 9 of the rail 1 causes the rail 1 and the slide unit 20 to slide relative to each other. I can exercise.

The holding plate 3 has a simple shape and has an effect that it can be easily manufactured. However, the positioning error between the casing 2 and the rail 1 forming the track grooves 8 and 9 and the holding Since the plate 3 is a thin plate, the holding plate 3
When the slide unit 20 slides on the rail 1, the ball 4, which is a rolling element, comes into contact with the holding plate 3 to increase the sliding resistance. When the ball 20 is removed, there is a problem that the ball 4 falls off.

As a method of holding the ball, a structure in which a ball holding portion is provided on a member having a raceway groove has been developed. However, in a type in which the raceway groove is formed directly on the side wall surface of the casing, the raceway is formed. There is a problem that it is difficult to insert a grindstone for forming a raceway groove in the casing into the raceway groove and to form a raceway surface in the casing because the holding portion below the groove hinders the formation of the raceway surface.

[0007] In order to solve the above-mentioned problem, for example, there is a holder for a linear motion guide unit as disclosed in Japanese Patent Application Laid-Open No. 64-11201. The holding of the ball by the linear motion guide unit will be outlined with reference to FIGS.
7 is a sectional view showing an example of a conventional linear motion rolling guide unit, and FIG. 8 is a perspective view showing an example of a holding plate incorporated in FIG. Since the linear motion rolling guide unit shown in FIGS. 7 and 8 has basically the same configuration and function as the linear motion rolling guide unit shown in FIG. 6, the same components are denoted by the same reference numerals. doing.

As shown in FIGS. 7 and 8, the holding plate 3 in the linear motion rolling guide unit includes a sealing portion 7 protruding in a lip shape, a sealing portion 10 having an upper surface 21 as a sealing surface, and a holding member for holding a rolling element. The part 6 is formed as an integral structure of the same material. In the linear motion rolling guide unit, the holding plate 3 is disposed in contact with the lower surface 12 of the casing 2, and the screw 16 is inserted into a through hole 15 formed in the holding plate 3 and screwed into a screw hole of the casing 2. Fixed by that. To hold the ball 4 in the casing 2, the raceway groove 8
The ball 4 is fitted to the raceway groove 8 and the holding portion 6 arranged along the wall surface 22 of the casing 2 on the bottom side thereof and the holding band 13 fixed at both ends of the casing 2.
Is held in the casing 2. In this case, the distance between the upper end edge 23 of the raceway groove 8 of the casing 2 and the leading edge 14 of the holding portion 6 of the holding plate 3 is formed larger than the diameter of the ball 4 so that the ball 4 can be fitted into the raceway groove 8. However, the distance between the holding band 13 and the tip edge 14 of the holding portion 6 is smaller than the diameter of the ball 4 so that the ball 4 does not fall off the casing 2.

The raceway groove 9 of the rail 1 and the raceway groove 8 of the casing 2 are formed in a substantially V-shaped groove, and the raceway surface is formed by an arcuate surface so that the load capacity is larger than a flat surface.
At the upper end face of the raceway groove 8 of the casing 2, an upper end edge 23 projecting toward the rail 1 from a perpendicular passing through the center of the ball 4 is formed. It is formed on two sides.

The holding plate 3 has a seal portion 7 formed on a seal lip, a seal portion 10 which can be in close contact with the lower surface 12 of the casing 2, and a holding portion 6 for holding the ball 4. Accordingly, the material of the holding plate 3 is made of a material such as plastic which is rich in elasticity so as to exert a sealing function and has a certain rigidity capable of locking the ball 4. The holding plate 3 can be manufactured by molding the seal portion 7, the seal portion 10, and the holding portion 6 into an integral structure by injection molding or the like.

[0011]

However, in the linear motion rolling guide unit, when the holding plate 3 is made of plastic such as synthetic resin, if the holding plate 3 is used for a long period of time, the holding plate 3 is not used. Are fixed to the casing 2 made of a metal material by screws 16 when the plastic holding plate 3 is swollen by the lubricating oil, the holding plate 3 cannot be moved relative to the casing 2 and the holding plate 3 is deformed. I do. When the holding plate 3 is deformed, the contact state between the lower surface 12 of the casing 2 and the upper surface 21 of the holding plate 3, that is, the close contact state becomes poor, or the seal portion 7 is deformed, and the seal portion 7 and the side surface of the rail 1 are deformed. 11, the sealing performance with respect to the linear motion rolling guide unit, particularly the dustproof effect, is reduced, and the holding portion 6 holding the ball 4 is deformed, and the leading edge 14 of the holding portion 6 and the holding band 13 are deformed. When the rail is separated from the slide unit, the weight of the plurality of balls 4 is added to the casing 2 so that the balls 4
Cannot be held, and the ball 4 falls off the casing 2.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problem, and a raceway groove is easily and precisely ground in a casing without being interfered by a holding plate provided for holding a rolling element in the casing. The holding plate is made separately from the casing so that it can be made, and the holding plate is easily and inexpensively made of plastic or the like. In particular, the holding plate is made of lubricant supplied to the sliding surface between the rail and the slide unit. Even if the swelling occurs, the holding plate is slidably mounted on the end cap so that the holding plate does not buckle, and the rolling element can always be securely held on the casing by the holding plate. An object of the present invention is to provide a linear motion rolling guide unit capable of always exhibiting good sealing performance with respect to a casing.

[0013]

SUMMARY OF THE INVENTION The present invention provides a rail having track grooves on both side walls in the longitudinal direction, and a track groove formed at a position slidable relative to the rail and opposed to each of the track grooves. Linear rolling guide unit having a fixed casing, a number of rolling elements fitted between the opposed raceways and relatively movable, and end caps attached to both longitudinal ends of the casing, the raceways of the casing. A holding portion capable of holding the rolling element on the bottom side of the first portion, a first seal portion capable of abutting along a lower wall surface of the track groove of the rail, and a second portion in close contact with the lower surface of the casing.
A holding plate provided with a seal portion, which is fitted into an engaging portion formed integrally with at least one end of the holding plate;
An engagement hole is formed in the end cap to allow the holding plate to extend in a movement direction that is a longitudinal direction of the casing, and at least one end of the holding plate slides in the end cap in the longitudinal direction of the casing. The present invention relates to a linear motion rolling guide unit which is mounted so as to be capable of being mounted.

The holding plate is made of plastic.

[0015] The engagement hole formed in the end cap has one end surface formed in an insertion portion into which the engagement portion of the holding plate can be inserted, and the other end surface restricts movement of the engagement portion by a predetermined amount or more. It is formed on the stopper.

[0016]

The linear motion rolling guide unit according to the present invention is constructed as described above. Therefore, even if the holding plate swells with a lubricant or the like or expands due to a difference in thermal expansion, the holding plate buckles. There is no deformation that bends.
Therefore, the holding plate can always securely hold the rolling element in the casing, and can always provide a good sealing portion on the sliding surface between the rail and the slide unit, and foreign matter such as dust and dirt enters the sliding surface. Can be prevented.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a linear motion rolling guide unit according to the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of a linear motion rolling guide unit according to the present invention, showing an assembled state of an end cap and a holding plate.
3 is a front view showing an embodiment of the end cap in the linear motion rolling guide unit according to the present invention, FIG. 3 is a bottom view of the end cap in FIG. 2, and FIG. 4 is an embodiment of a holding plate in the linear motion rolling guide unit according to the present invention. Plan view showing an example,
5 is an end view of the holding plate of FIG. In each of the drawings, components having the same functions as those of the components shown in FIGS. 6, 7, and 8 are denoted by the same reference numerals.

The linear motion rolling guide unit according to the present invention has basically the same configuration as the linear motion rolling guide unit shown in FIG. 6, and has a feature in mounting the holding plate 3. That is, this linear motion rolling guide unit is not shown, but is composed of a rail having track grooves formed on both side walls in the longitudinal direction similar to that shown in FIG. 6, and a slide unit which can slide relative to the rail. It is configured. The slide unit is slidable relative to the rail and has a casing (not shown) having a track groove formed at a position facing each of the track grooves. Numerous rolling elements (not shown), end caps attached to both ends in the longitudinal direction of the casing, holding plates attached to end caps 5, sealing members attached to end faces of end caps 3, scrapers, etc. Having.

FIG. 1 shows an end cap 5 to be incorporated in a linear motion rolling guide unit according to the present invention and a holding plate 3 detachably attached to the end cap 5. In FIG. 1, in order to clearly show the main part of the present invention, only the end cap 5 and the holding plate 3 are shown, and the rail, the casing, and the ball which is a rolling element are excluded.

As shown in FIGS. 2 and 3, the end cap 5 is mounted on both end surfaces of the casing by passing screws through a plurality of mounting holes 31, and a ball is provided inside the end cap 5. The direction change path 25 which changes the direction which circulates on the sliding surface between the casing and the rail is formed on both sides. A rail insertion recess 28 is formed in the end cap 5 so as to straddle the rail. On both sides of the recess 28, projections 32 for guiding the holding band are formed.

This linear motion rolling guide unit particularly has an engagement hole 24 formed in the lower surface 33 of the end cap 5 for attaching the holding plate 3 to the end cap 5 and the holding plate 3.
That is, the engaging portion 30 is provided on the upper surface 21 of the seal portion 10. In particular, as shown in FIGS. 2 and 3, the engagement hole 24 formed in the end cap 5 is formed such that the sectional shape of the engagement hole lower portion 26 is formed to have a small slit width and the engagement hole upper portion 27 is formed.
Is formed in a large blind hole so that the holding plate 3 can extend in the moving direction which is the longitudinal direction of the casing. One end surface is formed on the insertion portion 34 into which the engaging portion 30 of the holding plate 3 can be inserted, and the other end surface is formed on the stopper 35 for restricting the engagement portion 30 from moving more than a predetermined amount.
As shown in FIG. 5, the engaging portion 30 formed on the upper surface 21 of the holding plate 3 has a large cross-sectional shape at the distal end portion 29 and a small cross-sectional shape at the stem portion 37 at the root.
When the engaging portion 30 is inserted into the engaging hole 24, the distal end portion 29 of the engaging portion 30 is inserted and fitted into the upper portion of the engaging hole 27, and the stem portion 37 of the engaging portion 30 is inserted into the lower portion of the engaging hole. 26. Therefore, the holding plate 3 is configured to be movable relative to the end cap 5 in the sliding direction of the slide unit, but cannot be separated in the vertical direction.

As shown in FIGS. 4 and 5, the holding plate 3 in the linear motion rolling guide unit has a holding portion 6 capable of holding a rolling element at the bottom of the raceway groove of the casing, and a lower wall surface of the raceway groove of the rail. The seal 7 protrudes in the shape of a lip, which is disposed in abutment along the seal, the seal 10 which is disposed in close contact with the lower surface of the casing, and the engagement portion 30 which fits into the engagement hole 24 of the end cap 5. It is provided with. FIG.
4 and FIG. 4, the engaging portions 30 are provided at both ends of the holding plate 3. Since the holding plate 3 holds the rolling element by the holding part 6, seals the sliding surface with the rail by the seal part 7, and seals the space between the casing by the seal part 10, so that only the rolling element is held. It is preferable to manufacture from a material having rigidity and elasticity capable of exhibiting sealing performance, such as plastic.

In this linear motion rolling guide unit, in particular, by inserting the engaging portion 30 of the holding plate 3 into the engaging hole 24 of the end cap 5 and slidably attaching the holding plate 3 to the end cap 5, The holding plate 3 can move relative to the end cap 5 in the insertion direction, that is, the sliding direction of the slide unit. The engaging force of the holding plate 3 on the end cap 5 is, for example, when the holding plate 3 swells with a lubricant for lubricating the sliding surface and extends in the longitudinal direction.
The holding plate 3 is set to a force smaller than a buckling load that causes the holding plate 3 to buckle due to the swelling force, or the end cap 5 and a casing fixing the end cap 5 and the holding plate 3 The distance between the end caps 5 at both ends of the casing and the end cap 5
When there is a difference between the length of the holding plate 3 and the length of the holding plate 3, the holding plate 3 is set to a force smaller than a buckling load that causes the holding plate 3 to buckle due to the thermal expansion force. Thus, by holding the holding plate 3 movably in the sliding direction with respect to the end cap 5, the holding plate 3 does not always buckle or deform between both end caps 5. , Can maintain close contact with the underside of the casing and the side of the rail,
The rolling element can be securely held, and a good sealing state with respect to the rail and the casing can be ensured.

Although one embodiment of the linear motion rolling guide unit according to the present invention has been described above, the present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, the holding plate 3 has both ends. To form an engaging portion 30,
Although the holding plate 3 is slidably attached to the end caps 5 at both ends attached to the casing, both ends are not necessarily slidably attached. For example, one end of the holding plate 3 is attached to one end cap 5. Slidably mounted,
The other end of the holding plate 3 may be fixed to the other end cap 5 and, if necessary, to the lower surface of the casing with screws or the like. As described above, when the holding plate 3 is slidably attached to the casing 5 at only one end, the relative movement between the holding plate 3 and the end cap 5 is slightly reduced as compared with the above embodiment. The holding plate 3 can be configured so that buckling does not occur.

As a rolling element circulating in an endless track composed of a rail, a casing, and an end cap 5, not only a ball but also a roller may be used in some cases. Of course, not only two rails but also four rails can be used. Furthermore, the shape of the engagement hole 24 formed in the end cap 5 and the engagement portion 30 of the holding plate 3 can be configured to be slidable in a groove shape.

[0026]

Since the linear motion rolling guide unit according to the present invention is constructed as described above, even if the holding plate swells with a lubricant or the like or expands due to a difference in thermal expansion, the holding plate can be attached to the end cap. Relative to the end cap, the holding plate does not buckle and bend, and the holding plate can be easily attached to and removed from the end cap, thus improving the assemblability. it can. Therefore, the holding plate always holds the rolling element securely in the casing, and the holding plate is always in close contact with the lower surface of the casing and the end cap, so that the sliding surface between the rail and the slide unit always has a good seal. Department can be provided,
Foreign matter such as dirt, dust, and water can be prevented from entering the sliding surface, and dust resistance can be improved. In addition, since the holding plate is formed separately from the casing, the raceway grooves can be easily ground in the casing, the raceway grooves can be machined with high precision, and the bearing performance of the linear motion rolling guide unit can be improved. It can be greatly improved. In addition, this linear motion rolling guide unit used to make screw holes in the casing of the slide unit when the holding plate was attached to the slide unit as in the past, but such processing became unnecessary.
In addition, since the engaging portion can be integrally formed at the time of injection molding of the holding plate, the manufacturing cost can be greatly reduced.

Further, since the holding plate is made of plastic, the holding plate can be easily formed into an integral structure by injection molding or the like, and the manufacturing cost can be reduced. Furthermore,
Since the holding portion of the rolling element, the first seal portion, and the second seal portion are configured as an integral structure, the number of components can be reduced.

Further, the engaging hole formed in the end cap and extending in the moving direction has one end surface formed in an insertion portion into which the engaging portion of the holding plate can be inserted, and the other end surface formed in a predetermined shape of the engaging portion. Since the stopper is formed on the stopper for restricting the above movement, the holding plate does not move excessively with respect to the end cap, and the holding plate does not fall off from the end cap. The holding plate can be easily assembled to the end cap.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a linear motion rolling guide unit according to the present invention, showing an assembled state of an end cap and a holding plate.

FIG. 2 is a front view showing an embodiment of an end cap in the linear motion rolling guide unit according to the present invention.

FIG. 3 is a bottom view of the end cap of FIG. 2;

FIG. 4 is a plan view showing an embodiment of a holding plate in the linear motion rolling guide unit according to the present invention.

FIG. 5 is an end view of the holding plate of FIG. 4;

FIG. 6 is a perspective view showing an example of a conventional linear motion rolling guide unit.

FIG. 7 is a sectional view showing another example of a conventional linear motion rolling guide unit.

FIG. 8 is a perspective view showing an example of a holding plate incorporated in FIG. 7;

[Explanation of symbols]

 Reference Signs List 3 holding plate 5 end cap 6 holding portion 7 seal portion (first seal portion) 10 seal portion (second seal portion) 21 upper surface of holding plate 24 engagement hole 30 engagement portion 34 insertion portion 35 stopper

Claims (3)

(57) [Claims] 1. A rail having track grooves formed on both side walls in a longitudinal direction, a casing slidable relative to the rail, and a track groove formed at a position facing each of the track grooves.
In a linear motion rolling guide unit having a number of rolling elements fitted between opposed track grooves and relatively movable, and end caps attached to both longitudinal ends of the casing, a bottom side of the track groove of the casing. A holding plate provided with a holding portion capable of holding the rolling element, a first seal portion capable of abutting along a lower wall surface of the track groove of the rail, and a second seal portion in close contact with the lower surface of the casing. And formed integrally with at least one end of the holding plate.
Fits into the engaging part and in the longitudinal direction of the casing
A member for allowing the holding plate to extend in a certain moving direction;
A mating hole is formed in the end cap, and at least one end of the holding plate is attached to the end cap by the length of the casing.
A linear motion rolling guide unit which is slidably mounted in the hand direction . 2. The linear motion rolling guide unit according to claim 1, wherein the holding plate is made of plastic. 3. A pre-formed in the end cap Kigakarigoana, one end surface of the holding plate engaging portion is formed in the insertion portion can be inserted and the other end face of the predetermined amount or more of the engagement portion of the a linear motion rolling guide unit according to claim 1 or 2, characterized in that formed on the stopper for restricting movement.