Linear motion guide device

Abstract

To provide a linear motion guide device capable of reducing maintenance frequency of a side seal and reducing running costs.SOLUTION: A linear motion guide device includes a side seal mounted on an end portion in a moving direction of a slider. The side seal has a core metal, a plurality of seal portions kept into contact with a guide rail, an energization device generating energization force to the core metal, and a transmission mechanism for transmitting the energization force to the seal portions. The transmission mechanism has a first transmission portion for transmitting the energization force along a base shaft direction from the energization device to one of the seal portions, and a second transmission portion converting the energization force along the base shaft direction into energization force in a different shaft direction different from the base shaft direction and transmitting the same to other seal portions.SELECTED DRAWING: Figure 2B

Description

[Technical field]

[0001] The present invention relates to a linear guide device. [Background technology]

[0002] Linear guide devices use contact seals such as side seals, inner seals, and under seals. A typical side seal has a seal lip that slides on the top surface of the guide rail and the side surface including the raceway groove. When the seal lip wears out, it is no longer possible to maintain contact with the guide rail, and there is a risk that dust-proofing will decrease.

[0003] In response to this, Patent Document 1 discloses a technology in which a multi-layered seal lip is biased toward the guide rail by a spring, and the surface seal lip is removed each time it wears and a new surface seal lip is brought into contact with the guide rail, thereby maintaining sealing performance for a long period of time without the need to replace the side seal. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-163482 A Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 discloses a structure in which a U-shaped seal is pressed from above and from the outside in the width direction by a spring to bring the seal lip into contact with the upper surface and both side surfaces of the guide rail, and the surface layer can be removed if the seal lip becomes worn. However, removing the surface layer requires periodic maintenance of the side seal, which increases running costs.

[0006] The present invention has been made in consideration of the above problems, and has an object to provide a linear guide device that reduces the frequency of maintenance of the side seals and cuts running costs. [Means for solving the problem]

[0007] The linear guide device of the present invention is Guide rails and a slider arranged to move relative to the guide rail in a longitudinal direction; a plurality of rolling elements arranged to roll along a rolling element rolling path formed between the guide rail and the slider; a side seal attached to an end of the slider in a moving direction, the side seal includes a core metal, a plurality of seal portions that contact the guide rail, a biasing device that generates a biasing force on the core metal, and a transmission mechanism that transmits the biasing force to the seal portions; The transmission mechanism is characterized by having a first transmission part that transmits a biasing force along the basic axis direction from the biasing device to one of the seal parts, and a second transmission part that converts the biasing force along the basic axis direction into a biasing force in a different axial direction different from the basic axis direction and transmits it to the other seal part. Effect of the Invention

[0008] According to the present invention, it is possible to provide a linear guide device that can reduce the frequency of maintenance of the side seal and reduce running costs. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a linear guide device according to a first embodiment. [Figure 2A] 2A is a perspective view of a slider of the linear guide device shown in FIG. 1. FIG. [Figure 2B] FIG. 2B is a view of the core metal of the side seal as viewed from the plane AA in the direction of the arrow in FIG. 2A. [Figure 3A] FIG. 3A is a view of the core bar seen in the same direction as FIG. 2B. [Figure 3B] FIG. 3B is a perspective view of the core bar. [Figure 4] FIG. 4 is a view of the first seal portion in the same direction as FIG. 2B. [Diagram 5] FIG. 5 is a view of the second seal portion and the third seal portion viewed in the same direction as FIG. 2B. [Figure 6] FIG. 6 is a view similar to FIG. 2, showing a side seal according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0011] (First embodiment) Fig. 1 is a perspective view of a linear guide device 11 according to a first embodiment, and Fig. 2A is a perspective view of a slider 15 of the linear guide device 11 shown in Fig. 1. In Fig. 1 and Fig. 2A, screws for fixing a side seal 41 to an end cap 23 are omitted. Here, in an XYZ orthogonal coordinate system perpendicular to each other, the X direction is the width direction of the guide rail 13, the Y direction is the longitudinal direction of the guide rail 13, and the Z direction is the height direction of the guide rail 13 and the slider 15.

[0012] The linear guide device 11 according to this embodiment has a guide rail 13, a slider 15 that moves relative to the guide rail 13, rolling elements and a cage (not shown), and a seal member that closes the gap between the guide rail 13 and the slider 15. The multiple rolling elements are arranged to roll freely along a rolling element rolling path formed between the guide rail 13 and the slider 15, thereby allowing the slider 15 to move axially relative to the guide rail 13.

[0013] Here, the seal member is a general term for the side seal 41 attached to the end of the slider 15 in the moving direction, and an under seal and an inner seal (not shown).

[0014] A pair of guide rail side raceway surfaces (rolling element raceway surfaces) 19 are formed on the side surface of the guide rail 13 along the longitudinal direction of the guide rail 13. The slider 15 includes a slider body 21 and a pair of end caps 23 provided on both ends of the slider body 21 in the moving direction (longitudinal direction).

[0015] In the slider 15, side seals 41 are arranged on both sides of the end cap 23 in the longitudinal direction, and the side seals 41 are fixed to the end cap 23 by screws (not shown) that are inserted into the through holes 43i.

[0016] The slider body 21, end cap 23, and side seal 41 all have a U-shaped (or C-shaped) cross section and are installed to straddle the guide rail 13. That is, the slider body 21, end cap 23, and side seal 41 have a recessed groove formed in the center to accommodate the guide rail 13.

[0017] 2B is a view of the core metal 43 of the side seal 41 as viewed in the direction of the arrow from the AA surface in FIG. 2A, and is shown together with the guide rail 13 (hatched). Only one side seal 41 will be described here, but the other side seal 41 is similar, so a duplicated description will be omitted. Note that the terms "left" and "right" used below refer to "left" and "right" in the drawings.

[0018] The side seal 41 includes a metal core 43 held between the end cap 23 and the core 43, a first seal portion 44, a second seal portion 45, and a third seal portion 46 attached to the core 43, and a pair of coil springs 47. First, the core 43 will be described.

[0019] Fig. 3A is a view of the core bar 43 as viewed in the same direction as Fig. 2B, and Fig. 3B is a perspective view of the core bar 43. Like the end cap 23, the core bar 43 is also formed in a U-shape, and the upper edge and side edge of the core bar 43 coincide with the upper edge and side edge of the end cap 23. The height of the core bar 43 also coincides with the height of the end cap 23. Therefore, when the core bar 43 is attached to the end cap 23, there are no gaps at the upper edge and side edge, resulting in a structure that makes it difficult for foreign matter to enter.

[0020] The center of the lower part of the U-shaped core metal 43 is a notch 43a. The core metal 43 has an upper edge part 43b protruding in the Y direction, a pair of side edges 43c, and a lower edge part 43d sandwiching the notch 43a. The upper edge part 43b has two recesses 43e spaced apart in the X direction, and each recess 43e has an opening part that opens downward in the Z direction, and an island part 43f shaped like a long and narrow rectangular parallelepiped is formed at a position opposite the opening part and spaced from the upper edge part 43b.

[0021] The pair of side edges 43c have protruding parts 43g protruding opposite to each other in the X direction near the upper edge 43b. The protruding parts 43g are substantially equal in position and thickness in the Z direction to the island part 43f. The upper edge part 43b, the side edge part 43c, the lower edge part 43d, the island part 43f, and the protruding part 43g have flat end faces in the Y direction (faces on the front side in the direction perpendicular to the paper surface in FIG. 3A), and these end faces come into close contact with the opposing surface of the end cap 23 when assembled as the side seal 41. The surface 43h of the core metal 43 other than the upper edge part 43b, the side edge part 43c, the lower edge part 43d, the island part 43f, and the protruding parts 43g (hereinafter, referred to as the mounting surface) overlaps the ZX surface. A through hole 43i for inserting a screw is formed penetrating the upper edge part 43b in the Y direction.

[0022] Fig. 4 is a view of the first seal portion 44 viewed in the same direction as Fig. 2B. The first seal portion 44 has a uniform thickness in the Y direction and is made of synthetic resin or natural resin (rubber, etc.). The first seal portion 44 is connected to a load receiving portion 44a, an upper lip 44b, a left driving portion 44c, a right driving portion 44d, a central connecting portion 44e, a left connecting portion 44f, and a right connecting portion 44g.

[0023] The load receiving portion 44a is a rectangular column extending in the X direction, and the upper lip 44b is also a substantially rectangular column extending in the X direction parallel to the load receiving portion 44a. A pair of auxiliary lips 44j are formed to protrude downward from both ends of the upper lip 44b. The central connecting portion 44e connects the central portion of the load receiving portion 44a and the central portion of the upper lip 44b along the Z direction. The load receiving portion 44a and the central connecting portion 44e constitute a first transmission portion.

[0024] The left drive section 44c has a right-angled triangular shape with the upper side extending in the X direction and the left side extending in the Z direction, and a drive slope 44h corresponding to the hypotenuse faces the upper lip 44b. The inclination angle (inner angle) θ of the drive slope 44h with respect to the Z direction is preferably less than 45 degrees, and more preferably 30 degrees or less. The left connector 44f connects the vicinity of one end of the load receiving section 44a to the center of the upper edge of the left drive section 44c. The load receiving section 44a, the left connector 44f, and the left drive section 44c constitute a second transmission section. The first transmission section and the second transmission section constitute a transmission mechanism.

[0025] The right drive section 44d has a right-angled triangular shape with the upper side extending in the X direction and the right side extending in the Z direction, and the drive slope 44i corresponding to the hypotenuse faces the upper lip 44b. The inclination angle (inner angle) θ of the drive slope 44i with respect to the Z direction is preferably less than 45 degrees, and more preferably 30 degrees or less. The right connector 44g connects the vicinity of one end of the load receiving section 44a to the center of the upper edge of the right drive section 44d. The load receiving section 44a, the right connector 44g, and the right drive section 44d constitute a second transmission section. The first transmission section and the second transmission section constitute a transmission mechanism.

[0026] As shown by dashed lines in FIG. 4, for example, steel reinforcing material 44m can be embedded in the load-receiving portion 44a, the central connecting portion 44e, the left connecting portion 44f, and the right connecting portion 44g by insert molding to increase the rigidity of these portions.

[0027] Fig. 5 is a view of the second seal portion 45 and the third seal portion 46 viewed in the same direction as Fig. 2B. The second seal portion 45 and the third seal portion 46 have symmetrical shapes with respect to the center line of the core metal 43.

[0028] The second seal portion 45 is made of synthetic resin or natural resin (rubber, etc.) and has a right-angled trapezoidal main body portion 45a, a semicircular portion 45b formed so as to protrude rightward in the X direction from near the center of the right edge of the main body portion 45a, and a convex portion 45c formed so as to protrude rightward in the X direction from the apex of the semicircular portion 45b. The main body portion 45a has a driven slope 45d facing the semicircular portion 45b.

[0029] The third seal portion 46 is made of synthetic resin or natural resin (rubber, etc.) and has a right-angled trapezoidal main body portion 46a, a semicircular portion 46b formed so as to protrude leftward in the X-direction from near the center of the side edge of the main body portion 46a, and a convex portion 46c formed so as to protrude leftward in the X-direction from the apex of the semicircular portion 46b in the X-direction. The main body portion 46a has a driven slope 46d facing the semicircular portion 46b.

[0030] As shown in FIG. 2B, the first seal portion 44, the second seal portion 45, and the third seal portion 46 are assembled to the core metal 43, and their surfaces on the inner side in the direction perpendicular to the paper surface are in contact with the mounting surface 43h. More specifically, the load receiving portion 44a of the first seal portion 44 is disposed between the upper edge portion 43b and the island portion 43f and extends along the X direction. Since the load receiving portion 44a is held between the upper edge portion 43b and the island portion 43f, it is possible to prevent the first seal portion 44 from falling off the core metal 43 in the Z direction. In the initial state where the seal portions 44 and 46 are assembled to the guide rail 13, a gap exists between the load receiving portion 44a and the island portion 43f.

[0031] Moreover, the central connecting portion 44e passes between the pair of island portions 43f, and the upper lip 44b is located below the island portions 43f in the Z direction.

[0032] On the other hand, the left connecting portion 44f passes between the left protruding portion 43g and the island portion 43f, and the second seal portion 45 is located below the left protruding portion 43g and the island portion 43f in the Z direction. Furthermore, the right connecting portion 44g passes between the right protruding portion 43g and the island portion 43f, and the third seal portion 46 is located below the right protruding portion 43g and the island portion 43f in the Z direction.

[0033] Further, the lower edges of the main body portions 45a, 46a of the second seal portion 45 and the third seal portion 46 abut against the lower edge portion 43d of the core metal 43 and are guided thereby to be movable in the X direction. That is, the lower edge portion 43d serves as a guide for the second seal portion 45 and the third seal portion 46 in the X direction.

[0034] The driven slope 45d of the main body 45a slidably abuts against the driving slope 44h of the left driving part 44c, and the driven slope 46d of the main body 46a slidably abuts against the driving slope 44i of the right driving part 44d. In this embodiment, a guide member GD (a modified example described later) is not arranged between the left side edge 43c and the left driving part 44c, and between the right side edge 43c and the right driving part 44d, and there are gaps of 0.1 mm to 0.2 mm between the left side edge 43c and the left driving part 44c, and between the right side edge 43c and the right driving part 44d. Because of the presence of such gaps, the Z-direction displacement of the left driving part 44c and the right driving part 44d is not hindered.

[0035] A pair of coil springs 47 constituting the biasing device are respectively assembled in recesses 43e spaced apart in the X direction. The coil springs 47 compressed in the Z direction stably bias the load receiving portion 44a downward in the Z direction (referred to as the base axis direction) against the inner wall 43k of the recess 43e.

[0036] By assembling the core bar 43, to which the first seal portion 44, the second seal portion 45, the third seal portion 46, and the coil spring 47 are assembled, to the end face of the end cap 23 of the slider 15, the side seal 41 is assembled to the slider 15 and the first seal portion 44 etc. are prevented from falling off from the core bar 43.

[0037] 2B, when the slider 15 is attached to the guide rail 13, the upper lip 44b of the first seal portion 44 can come into contact with the upper surface of the guide rail 13. At this time, the auxiliary lips 44j at both ends of the upper lip 44b engage with the guide rail side raceway surfaces 18 on both sides of the upper surface of the guide rail 13, and come into contact with the upper ends of the second seal portion 45 and the third seal portion 46.

[0038] Furthermore, the main body portions 45a, 46a and the semicircular portions 45b, 46b of the second seal portion 45 and the third seal portion 46 can come into contact with the side surface of the guide rail 13. At this time, the convex portions 45c, 46c enter and come into contact with the guide rail side raceway surface 19. As a result, the upper surface and the side surface of the guide rail 13 are sealed, so that intrusion of foreign matter into the slider 15 is suppressed.

[0039] (Side seal action) The Z-directional biasing force of the coil spring 47 is transmitted from the load-receiving portion 44a via the central connecting portion 44e to the upper lip 44b, thereby pressing the upper lip 44b against the upper surface of the guide rail 13, thereby ensuring the tightening margin of the upper lip 44b and improving the sealing performance.

[0040] Also, the biasing force of the coil spring 47 in the Z direction is transmitted from the load receiving portion 44a to the left driving portion 44c via the left connecting portion 44f. As a result, the left driving portion 44c is displaced downward in the Z direction, but since the driving slope 44h and the driven slope 45d are in slidable contact with each other and the second seal portion 45 is guided by the lower edge portion 43d and can be displaced only in the X direction (called the different axial direction), the downward displacement (biasing force) of the left driving portion 44c in the Z direction is converted into a rightward displacement (biasing force) of the second seal portion 45 in the X direction. Therefore, the second seal portion 45 is pressed against the left side surface of the guide rail 13, thereby ensuring the tightening margin of the second seal portion 45 and improving the sealing performance.

[0041] Similarly, the biasing force of the coil spring 47 in the Z direction is transmitted from the load receiving portion 44a to the right driving portion 44d via the right connecting portion 44g. As a result, the right driving portion 44d is displaced downward in the Z direction, but since the driving inclined surface 44i and the driven inclined surface 46d are in slidable contact with each other and the third seal portion 46 is guided by the lower edge portion 43d and can be displaced only in the X direction, the downward displacement (biasing force) of the right driving portion 44d in the Z direction is converted into a leftward displacement (biasing force) of the third seal portion 46 in the X direction. Therefore, the third seal portion 46 is pressed against the right side surface of the guide rail 13, thereby ensuring the tightening margin of the third seal portion 46 and improving the sealing performance.

[0042] Furthermore, when the slider 15 slides relative to the guide rail 13 during use of the linear guide device 11, the upper lip 44b slides relative to the upper surface of the guide rail 13, and the sliding portion of the upper lip 44b wears accordingly. According to this embodiment, the biasing force of the coil spring 47 in the Z direction is transmitted from the load receiving portion 44a to the upper lip 44b via the central connecting portion 44e, so that when the sliding portion of the upper lip 44b wears, the upper lip 44b is displaced downward in the Z direction by the amount of wear, thereby ensuring the tightening margin of the upper lip 44b and maintaining the sealing performance.

[0043] In addition, when the slider 15 slides relative to the guide rail 13, the second seal portion 45 slides relative to the left side surface of the guide rail 13, and the sliding portions of the main body portion 45a and the semicircular portion 45b wear accordingly. According to this embodiment, the Z-direction biasing force of the coil spring 47 is transmitted from the load receiving portion 44a to the left driving portion 44c via the left connecting portion 44f, and is further converted into an X-direction biasing force by the driving slope 44h and the driven slope 45d, and transmitted to the second seal portion 45. Therefore, when the sliding portions of the main body portion 45a and the semicircular portion 45b wear, the second seal portion 45 is displaced rightward in the X direction by the amount of wear, thereby ensuring the tightening margin of the second seal portion 45 and maintaining the sealing performance.

[0044] Furthermore, when the slider 15 slides relative to the guide rail 13, the third seal portion 46 slides relative to the right side surface of the guide rail 13, and the sliding portions of the main body portion 46a and the semicircular portion 46b wear accordingly. According to this embodiment, the Z-direction biasing force of the coil spring 47 is transmitted from the load receiving portion 44a to the right driving portion 44d via the right connecting portion 44g, and is further converted into an X-direction biasing force by the driving slope 44i and the driven slope 46d, and is transmitted to the third seal portion 46. Therefore, when the sliding portions of the main body portion 46a and the semicircular portion 46b wear, the third seal portion 46 is displaced to the left in the X direction by the amount of wear, thereby ensuring the tightening margin of the third seal portion 46 and maintaining the sealing performance. According to this embodiment, the frequency of maintenance of the side seal 41 can be reduced, and the running cost of the linear guide device 11 can be reduced.

[0045] (Modification) As a modification of this embodiment, as shown by dotted lines in Fig. 2B, a guide member GD made of, for example, PTFE can be disposed between the left side edge 43c and the left driving part 44c, and between the right side edge 43c and the right driving part 44d. In this case, the guide member GD can be fixed to the left side edge 43c (or the left driving part 44c) and also to the right side edge 43c (or the right driving part 44d).

[0046] When the left driving part 44c receives a downward biasing force in the Z direction via the left connecting part 44f, the left driving part 44c is pushed back to the left in the X direction by a reaction force from the driven inclined surface 45d. At this time, the guide member GD slides against the left driving part 44c (or the side edge part 43c) while supporting the reaction force, thereby suppressing the displacement of the left driving part 44c to the left in the X direction and guiding it along the downward Z direction. Therefore, the second seal part 45 can be stably displaced to the right in the X direction.

[0047] Furthermore, when the right drive part 44d receives a downward biasing force in the Z direction via the right connector 44g, the right drive part 44d is pushed back to the right in the X direction by a reaction force from the driven inclined surface 46d. At this time, the guide member GD slides against the right drive part 44d (or the side edge part 43c) while supporting the reaction force, thereby suppressing the displacement of the right drive part 44d to the right in the X direction and guiding it along the downward Z direction. Therefore, the third seal part 46 can be stably displaced to the left in the X direction.

[0048] In addition, instead of placing the guide member GD, the thickness of each of the side edge portions 43c may be increased so that the left side edge portion 43c and the left side drive portion 44c are slidably abutted against each other, and the right side edge portion 43c and the right side drive portion 44d are slidably abutted against each other.

[0049] Second embodiment Fig. 6 is a view similar to Fig. 2B showing a side seal 41A according to the second embodiment, but the guide rail is omitted. In this embodiment, only the core bar 43A and the elastic member 47A provided as a biasing device instead of the coil spring are different from the first embodiment, so the same reference numerals are used for the common components and duplicated explanations are omitted.

[0050] The core bar 43A differs from the first embodiment in that a recess 43Ae formed in an upper edge portion 43Ab is expanded in the X direction and is single, and therefore a duplicated description of the other common configurations will be omitted.

[0051] In this embodiment, a block-shaped elastic member 47A made of synthetic resin or natural resin is elastically deformable and is disposed in the recess 43Ae in a state compressed in the Z direction. The elastic member 47A stably biases the load receiving portion 44a downward in the Z direction against the inner wall 43Ak of ​​the recess 43Ae. This allows the first seal portion 44 to be displaced downward in the Z direction, and the second seal portion 45 and the third seal portion 46 to be displaced so as to approach each other in the X direction, as in the first embodiment.

[0052] The present invention is not limited to the above-described embodiments, and the present invention also contemplates the mutual combination of the various components of the embodiments, as well as modifications and applications by those skilled in the art based on the description in the specification and well-known techniques, and these are included in the scope of protection sought. [Explanation of symbols]

[0053] 11 Linear guide device 13 Guide rail 15 Slider 18 Guide rail side raceway surface 19 Guide rail side raceway surface 21 Slider body 23 End cap 41,41A Side seal 43,43A,43B Core metal 43a Notch 43b,43Ab upper edge 43c Side edge 43d Lower edge 43f Island 43g protrusion 43h Mounting surface 43i through hole 43k,43Ak Back wall 44,44B First seal part 44a Load receiving part 44b Upper lip 44c Left drive 44d Right drive section 44e Central connection 44f Left side connection part 44g Right side connection part 44h, 44i Drive slope 44j Auxiliary lip 44m Reinforcement 45 Second seal part 45a, 46a Main body 45b, 46b Semicircular section 45c,46c convex part 45d, 46d Driven slope 46,46B 3rd seal part 47A Elastic member

Claims

1. Guide rails and a slider arranged to move relative to the guide rail in a longitudinal direction; a plurality of rolling elements arranged to roll along a rolling element rolling path formed between the guide rail and the slider; a side seal attached to an end of the slider in a moving direction, the side seal includes a core metal, a plurality of seal portions that contact the guide rail, a biasing device that generates a biasing force on the core metal, and a transmission mechanism that transmits the biasing force to the seal portions; The transmission mechanism includes a first transmission part that transmits a biasing force from the biasing device along the fundamental axis direction to one of the seal parts, and a second transmission part that converts the biasing force along the fundamental axis direction into a biasing force in a different axis direction different from the fundamental axis direction and transmits the biasing force to the other seal part. A linear motion guide device characterized by the above.

2. the seal portion includes a first seal portion that contacts an upper surface of the guide rail, and a second seal portion and a third seal portion that contact side surfaces of the guide rail; The first transmission portion transmits a biasing force along the basic axis direction to the first seal portion, The second transmission portion converts a biasing force along the basic axis direction into biasing forces in the different axis directions opposing each other and transmits the biasing force to the second seal portion and the third seal portion.

2. The linear guide device according to claim 1 .

3. the second transmission portion has a drive portion having a drive slope inclined with respect to the basic axis direction, the second seal portion and the third seal portion each have a driven inclined surface that slidably contacts the driving inclined surface; 3. The linear guide device according to claim 2 .

4. The inclination angle θ of the driving slope with respect to the base axis direction is less than 45 degrees.

4. The linear guide device according to claim 3.

5. A guide member is disposed between the core bar and the drive unit to guide the drive unit along the basic axis.

5. The linear guide device according to claim 3 or 4.

Images