JP2010084811A - Movement guide device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a movement guide device capable of giving a sufficient sealing effect between a raceway shaft and a moving member, securing smooth operation of the moving member relative to the raceway shaft. <P>SOLUTION: This movement guide device is structured of: the raceway shaft; the moving member moving along the raceway shaft; and a seal member installed in both ends of the moving member in the axial direction to seal a gap between the moving member and the raceway shaft. The seal member has a seal surface facing the raceway shaft, and the seal surface is formed with a plurality of grooves extending in a direction crossing the moving direction of the moving member to divide the seal surface into fine projections brought in contact with the raceway shaft. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a motion guide device in which a moving member and a track shaft are assembled so as to be relatively movable via a large number of rolling elements such as balls and rollers, and more specifically, a gap between the moving member and the track shaft. The present invention relates to a motion guide device provided with a seal member that closes the door.

  As an example of this type of motion guide device, a linear guide device is known in which a moving block carrying a movable body such as a table moves continuously along a track rail laid on a fixed part such as a bed or a column. Yes. In this linear guide device, the moving block is assembled to the track rail via a large number of balls, and the ball moves to the moving block by applying a load between the moving block and the track rail. It is possible to move the mounted movable body along the track rail. Further, the moving block is provided with an infinite circulation path for the ball, and by circulating the ball in the infinite circulation path, the moving block can continuously move along the track rail. ing.

  In this linear guide device, if dust or foreign matter enters the gap between the track rail and the moving block, it will cause abnormal wear of the rolling elements and the rolling surface of these rolling elements, and this shortens the life of the device. A dustproof means for preventing intrusion of dust and foreign matters through the gap is required.

  Conventionally, a seal member made of urethane rubber or the like is known as such a dustproof means (Japanese Patent Laid-Open No. 9-42284). The seal members are attached to both ends of the moving block in the moving direction, and the tips of the lip portions provided on the seal members are in close contact with the surface of the track rail. The lip portion is formed like a spire like a wiper used in an automobile and is in contact with the surface of the track rail in a bent state. And this seal member removes the dust and foreign matter adhering to the track rail with the movement of the moving block, or the coolant used for machining at the lip portion, and these foreign matters enter the inside of the moving block. Is configured to obtain a so-called sealing effect.

Also, a structure for mounting a plurality of seal members on a moving block in a state where a plurality of the seal members are stacked has been proposed as a case where the linear guide device is used in an environment where many foreign matters adhere to the track rail. .
JP-A-9-42284

  However, since the conventional seal member advances on the track rail so as to scrape off deposits on the track rail surface at the tip of the lip portion, the lubricating oil adhering to the track rail surface is wiped off at the same time. It tends to end up. For this reason, the sealing member formed of urethane rubber has a problem that a frictional force generated between the lip portion and the track rail is large, and it is difficult to secure a light movement of the moving block with respect to the track rail. Further, from the viewpoint of reducing the frictional force between the lip portion and the track rail, it is difficult to extremely increase the pressure contact force of the lip portion with respect to the track rail, and as a result, it is difficult to obtain a sufficient sealing effect.

  Further, such a problem is not limited to the linear guide device in which the moving block and the track rail are combined, but a ball spline device in which the spline nut moves along the spline shaft, and the nut member moves in a spiral manner around the screw shaft. This was common to ball screw devices.

  The present invention has been made in view of such problems, and the object thereof is to provide a sufficient sealing effect between the track rail and the moving block while ensuring the smooth operation of the moving block with respect to the track rail. It is an object of the present invention to provide a motion guide device capable of providing a motion.

  That is, the motion guide device of the present invention has a track axis, a moving member that moves along the track axis, and a gap between the moving member and the track shaft that is mounted on both ends of the moving member in the axial direction. The oil film levitation seal has a seal surface facing the track axis, and a plurality of grooves extending in a direction perpendicular to the axial direction are formed on the seal surface, The seal surface is divided into minute protrusions that contact the track axis.

  In the motion guide device of the present invention, the oil film levitation seal has a movable protrusion protruding in the axial direction of the track axis, and the seal surface is formed on a surface of the movable protrusion facing the track axis. Yes.

  Furthermore, in the motion guide apparatus according to the present invention, the oil film floating seal is formed with an oil intake surface that is continuous with the seal surface and forms a wedge-shaped space that expands toward the inside of the moving member in combination with the track shaft. Has been.

  Furthermore, in the motion guide device of the present invention, an air-fuel mixture sprayed with lubricating oil is forcibly introduced into the moving member.

  In the motion guide device of the present invention, the oil film levitation seal is mounted on the moving member so as to be displaceable, and is biased toward the track axis.

  Furthermore, in the motion guide device of the present invention, a seal frame surrounding the periphery of the moving member is provided, and the oil film levitation seal is fixed to the seal frame, while the seal frame is attached to the seal frame. And a packing portion for closing a gap between the movable member and the movable member.

  According to the motion guide device of the present invention, a plurality of grooves extending in a direction perpendicular to the axial direction of the moving member are formed on the seal surface of the oil film levitation seal, and the seal surface is formed on the plurality of minute protrusions in contact with the track axis. Since it is divided, the lubricating oil that has entered the groove tends to form an oil film between the minute protrusion and the surface of the track shaft with the movement of the moving member. During the movement of the moving member, the seal surface and the track shaft It becomes possible to always maintain an oil film during this period. For this reason, it is possible to reduce the frictional force acting between the oil film levitation seal and the track shaft, and to ensure smooth movement of the moving member relative to the track shaft.

  Hereinafter, the motion guide apparatus of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an exploded perspective view showing an embodiment in which the present invention is applied to a linear guide device. This linear guide device is formed through a track rail 1 as a track axis formed in a straight line and having a rolling surface 11 of a rolling element formed along the longitudinal direction, and a large number of balls 3 as rolling elements. A moving block 2 as a moving member that is assembled to the track rail 1 and has an infinite circulation path for the ball inside, and mounted on both ends of the moving block 2 in the moving direction, that is, in the axial direction, and the moving The end seal member 4 that closes the clearance between the track rail 1 and the moving block in the direction is configured so that the moving block 2 reciprocates along the track rail 1 as the ball 3 circulates. Yes. This end seal 4 member corresponds to the oil film floating seal of the present invention.

  The moving block 2 includes a block body 23 having a mounting surface 21 for a mechanical device such as a table and a ball return hole 22 for circulating the ball 3, and fixed to both end surfaces of the block body 23. It is comprised from a pair of cover body 24. FIG. The lid 24 is formed with a direction changing path (not shown) for the ball 3. The direction changing path scoops up the ball 3 from the rolling surface 11 of the track rail 1 and sends it to the ball return hole 22 of the block body 23, while feeding the ball 3 to the rolling surface 11 from the ball return hole 22. . The lid 24 is fixed to the block main body 23 with the mounting bolts 25 so that the infinite circulation path of the ball 3 is completed in the moving block 2.

  Further, the lid 24 is provided with an oil supply port 26 for injecting lubricating oil into the infinite circulation path, and a supply pipe 27 is attached to the oil supply port 26 via the end seal member 4. It has come to be. An air-fuel mixture containing sprayed lubricating oil is supplied to the supply pipe 27, and the air-fuel mixture is forcibly sent into the moving block 2 by a compressor (not shown).

  In this embodiment, the track rail is formed in a straight line shape, but may be formed in an arc shape having a constant curvature. In that case, the moving block reciprocates in an arc shape along the track rail. Further, the rolling elements interposed between the track rail and the moving block are not limited to balls, and may be rollers.

  On the other hand, the end seal member 4 is attached to the moving block 2 from above the lids 24 by fixing bolts 28. As shown in FIG. 1, the end seal member 4 has a guide groove substantially matching the cross-sectional shape of the track rail 1, and an end seal portion 40 is formed around the guide groove.

  FIG. 2 is an enlarged sectional view showing details of the end seal member 4. The end seal member 4 includes a seal plate 41 serving as a fixed substrate for the moving block 2 and a seal body 42 fixed to the surface of the seal plate 41. Part of it. The seal plate 41 is made of a hard material such as a metal plate or engineering plastic, while the seal body 42 is made of rubber or a thermoplastic elastomer.

  The end seal member 4 is fixed to the moving block 2 with the seal plate 41 in contact with the moving block 2, and the seal portion 40 moves from the seal body 42 in the opposite direction to the moving block 2, that is, moves. It is formed to protrude in the moving direction of the block 2 (arrow A direction). The surface of the seal portion 40 that faces the track rail 1 is a seal surface 43, and the groove 44 extends in the seal surface 43 in a direction perpendicular to the paper surface of FIG. 2, that is, in a direction perpendicular to the moving direction A of the moving block 2. A plurality of are formed. Therefore, the sealing surface 43 is divided into a plurality of minute protrusions by these grooves 44, and these minute protrusions are configured to contact the surface of the track rail 1.

  The groove 44 divides the seal surface 43 into a plurality of minute projections to facilitate the deformation of the seal surface 43, and reduces the contact surface pressure between the seal surface 43 and the surface of the track rail 1. Oil film formation with the track rail 1 is promoted. Further, the formation of an oil film between the seal surface 43 and the track rail 1 is also promoted by the lubricating oil entering and being held in the groove 44.

  An oil intake surface 45 that is continuous with the seal surface 43 is formed at an end of the seal portion 40 on the moving block 2 side so as to be inclined with respect to the seal surface 43. A wedge-shaped space is formed between the surface of the track rail 1.

  And in the linear guide device comprised as mentioned above, even if it moves the movement block 2 along the track rail 1 in the state which contact | abutted the seal surface 43 of the end seal member 4 to the track rail 1, this end Lubricating oil adhered to the surface of the track rail 1 by the seal member 4 is not completely removed, and the end seal member 4 is attached to the track rail 1 with an oil film remaining between the seal surface 43 and the surface of the track rail 1. It becomes possible to make it slide. That is, the seal surface 43 of the end seal member 4 is in contact with the track rail 1 through the oil film of the lubricating oil, and the sliding resistance between the end seal member 4 and the track rail 1 is reduced, and the moving block with respect to the track rail 1 is reduced. 2 can be ensured. In addition, since the seal surface 43 of the end seal member 4 is in contact with the track rail 1 through only a very thin oil film, there is no gap between the seal surface 43 and the surface of the track rail 1, and from the outside. It becomes possible to reliably prevent foreign matters such as dust or coolant from entering the inside of the moving block 2.

  The end seal member 4 is provided with an oil intake surface 45 continuous to the seal surface 43, and a wedge-shaped space is formed between the oil intake surface 45 and the track rail 1, so that the end seal member 4 has an end. When the seal member 4 moves on the track rail 1 together with the moving block 2, the lubricating oil in the moving block 2 is collected with respect to the wedge-shaped space expanded toward the moving block 2, and the collected lubricating oil is collected. Is guided by the oil intake surface 45 and flows between the seal surface 43 and the track rail 1. Thereby, the formation of the oil film between the seal surface 43 and the surface of the track rail 1 is further promoted, and the sliding resistance between the end seal member 4 and the track rail 1 can be reduced.

  Further, the end seal portion 40 protrudes from the seal body 42 in the moving direction of the moving block 2, and the seal surface 43 is formed on the surface of the seal portion 40 facing the track rail 1. Therefore, when the contact surface pressure between the seal surface 43 and the track rail 1 is increased, the seal portion 40 is bent so as to reduce the contact surface pressure. This also causes the surface of the seal surface 43 and the track rail 1 to be reduced. It is possible to promote the formation of an oil film between the seal surface 43 and the track rail 1. That is, the seal portion 40 corresponds to the movable protrusion portion of the present invention.

  Furthermore, in this linear guide device, the air-fuel mixture containing lubricating oil is forcibly sent into the moving block 2 through the supply pipe 27, so that the atmospheric pressure inside the moving block 2 is also the external atmospheric pressure. This is slightly higher, and this also makes it easier for the lubricating oil to enter between the seal surface 43 of the seal portion 40 and the surface of the track rail 1 to form an oil film. Also in this respect, it is possible to reliably form an oil film between the end seal member 4 and the track rail 1 and reduce the sliding resistance between the end seal member 4 and the track rail 1.

  FIG. 3 shows another example of the end seal member attached to the moving block 2.

  If the seal body 42 of the end seal member 4 is fixed to the moving block 2 as in the example shown in FIG. 2, when the moving block 2 is displaced with respect to the track rail 1, the seal surface 43 and the track rail There is a possibility that the contact surface pressure with 1 will increase, the oil film between them will break, and the sliding resistance of the seal member with respect to the track rail 1 will increase. For this reason, in the end seal member 5 shown in FIG. 3, the seal body 52 is held displaceably with respect to the seal plate 51 fixed to the moving block 2. That is, the seal plate 51 is provided with a slit holding portion 51a, and the seal body 52 is inserted into the slit holding portion 51a. Further, the seal main body 52 is not inserted into the deepest part of the slit holding portion 51a in contact with the track rail 1, but freely moves forward and backward from the surface of the track rail 1 in the state inserted in the slit holding portion 51a. Configured to get. Since the configuration of the seal portion 40 is not changed from that shown in FIG. 2, the same reference numerals as those in FIG. 2 are given in FIG. 3, and the detailed description thereof is omitted.

  According to the end seal member 5 shown in FIG. 3, the seal body 52 can be freely displaced with respect to the seal plate 51 fixed to the moving block 2. Even when a load is applied and the moving block 2 is displaced with respect to the track rail 1, an increase in the contact surface pressure between the seal surface and the track rail is avoided by the displacement of the seal body. It is possible to reliably maintain a state in which an oil film is interposed between the seal surface 43 and the track rail 1.

  By the way, it is not possible to completely seal the gap between the track rail 1 and the moving block 2 only by attaching the end seal member 4 to the moving block 2, and FIG. As described above, the side seal member 6 that blocks between the side surface of the track rail 1 and the moving block 2 along the longitudinal direction of the moving block 2, and the upper surface of the track rail 1 and the moving block 2 along the longitudinal direction of the moving block 2 It is necessary to attach the inner seal member 7 that closes the gap to the moving block 2. Further, if there is a gap between the end seal member 4, the side seal member 6, and the inner seal member 7, foreign matter or coolant liquid enters the moving block 2 from the gap.

  Therefore, from the viewpoint of making the cooperation of the seal members good and completely preventing foreign matter and liquid from entering the inside of the moving block 2, as shown in FIG. 4, the end seal member 4 and the side seal member It is preferable to provide a seal frame 8 in which 6 and the inner seal member 7 are integrated, and to fit the moving block 2 inside the seal frame 8.

  The seal frame 8 is formed of synthetic resin, and is configured such that the moving block 2 is fitted into the seal frame 8 from above in FIG. Further, a seal portion 9 of the oil film levitation seal of the present invention is provided by using rubber or thermoplastic elastomer at a portion where the seal frame body 8 faces the track rail 1, and the seal portion 9 attaches the seal frame body 8 to the seal frame body 8. The track rail 1 and the moving block 2 are provided so as to seamlessly surround a portion facing each other. Further, a rubber packing 80 is provided at the periphery of the opening of the seal frame 8 to which the moving block 2 is fitted, and foreign matter and liquid are introduced into the moving block 2 from the gap between the seal frame 8 and the moving block 2. To prevent intrusion.

  The application target of the present invention is not limited to the linear guide device shown in the above-described embodiment, but can be applied to a ball spline device and a ball screw device. That is, the motion guide device of the present invention is a concept including these devices.

It is a disassembled perspective view which shows an example of the linear guide apparatus to which this invention is applied. It is an expanded sectional view showing a first embodiment of a seal member of the present invention. It is an expanded sectional view which shows 2nd embodiment of the sealing member of this invention. It is a perspective view which shows the seal frame for sealing a moving block.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Track rail, 2 ... Moving block, 3 ... Ball, 4 ... End seal member (oil-film floating seal), 40 ... Seal part, 43 ... Seal surface, 44 ... Groove

Claims (6)

A track axis, a moving member that moves along the track axis, and an oil film levitation seal that is attached to both ends of the moving member in the axial direction and closes a gap between the moving member and the track axis,
The oil film levitation seal has a seal surface facing the track axis, and a plurality of grooves extending in a direction perpendicular to the axial direction is formed on the seal surface, and the seal surface is divided into minute projections that contact the track axis. A motion guide device characterized by being made. 2. The oil film levitation seal has a movable projection protruding in the axial direction of the track axis, and the seal surface is formed on a surface of the movable projection facing the track axis. Exercise guide device. The oil film levitation seal is formed with an oil intake surface that is continuous with the seal surface and forms a wedge-shaped space that expands toward the inside of the moving member in combination with a track shaft. The exercise guide apparatus according to 1. The motion guide apparatus according to claim 1, wherein an air-fuel mixture sprayed with lubricating oil is forcibly introduced into the moving member. The motion guide apparatus according to claim 1, wherein the oil film levitation seal is mounted so as to be displaceable with respect to the moving member, and is urged toward the track axis. A seal frame that surrounds the periphery of the moving member is provided, and the oil film floating seal is fixed to the seal frame, and the sealing frame has a packing portion that closes a gap between the seal frame and the moving member. The motion guide device according to claim 1, wherein the motion guide device is provided.

Images