JP6452303B2 - Clamper with linear motion guide - Google Patents

Description

  The present invention relates to a clamper that holds a shaft, and more particularly to a clamper with a linear motion guide provided with a linear motion guide.

As a conventional clamper of this type, for example, the one described in Patent Document 1 is known. That is, an outer cylinder (stopper main body) provided with a tapered surface between which the gap gradually decreases toward one of the extending directions of the shaft between the surface of the shaft, a rolling element disposed on the tapered surface portion, A cage that holds the moving body, and a spring that presses the rolling element in a direction to bite into the tapered surface via the cage and presses the rolling element against the surface of the shaft and the tapered surface are provided.
By setting it as such a structure, it became the structure by which the relative movement of the outer cylinder to the side with a large clearance of a taper surface with respect to a shaft was blocked | prevented.

Japanese Patent Laid-Open No. 11-4508

Conventionally, however, a friction material such as a brake shoe is used to clamp the rail or the shaft, so that it deforms when a load is applied, and the contact load of the friction material may decrease to reduce the holding force.
An object of the present invention is to provide a clamper with a linear motion guide that is compact and has a large holding force integrated with a linear motion guide in which rolling elements roll in an endless circulation.

In order to solve the above problems, the present invention provides:
An axially extending track shaft,
An outer cylinder inserted into the raceway shaft and having a tapered surface facing the raceway shaft;
A rolling element for clamping sandwiched between the tapered surface of the outer cylinder and the raceway shaft;
A cage for holding the rolling element for clamping;
An urging member that is provided between the outer cylinder and the cage and urges the rolling element for clamping in a direction to bite into the tapered surface;
The outer cylinder is provided with a plurality of rolling element rolling surfaces extending in the axial direction in which a large number of rolling elements for guide contact in a freely rolling manner, in the circumferential direction,
The retainer is provided with a circulation path that holds the rolling element for guidance and circulates from one end of the rolling element rolling surface to the other end,
The cage can be moved in the axial direction with respect to the outer cylinder, and the urging member is urged against the outer cylinder by the urging member , so that the clamping rolling element is attached in a direction to be engaged with the tapered surface. It is characterized by

In addition, other inventions
An axially extending track shaft,
An outer cylinder inserted into the raceway shaft and having a tapered surface facing the raceway shaft;
A rolling element for clamping sandwiched between the tapered surface of the outer cylinder and the raceway shaft;
A cage for holding the rolling element for clamping;
An urging member that is provided between the outer cylinder and the cage and urges the rolling element for clamping in a direction to bite into the tapered surface;
The outer cylinder is provided with a plurality of rolling element rolling surfaces extending in the axial direction in which a large number of rolling elements for guide contact in a freely rolling manner, in the circumferential direction,
The retainer is provided with a circulation path that holds the rolling element for guidance and circulates from one end of the rolling element rolling surface to the other end,
The outer cylinder is divided into a first outer cylinder part having a rolling element rolling surface of the rolling element for guidance and a second outer cylinder part assembled to the first outer cylinder part so as to be movable in the axial direction. ,
The cage is fixed so as not to move relative to the first outer cylinder portion in the axial direction, and the second outer cylinder portion is urged by the urging member .
Further, the second rolling element can be a good roller.
Moreover, the groove | channel for a 1st rolling element to roll may be provided in the 1st outer cylinder and the track shaft.

  According to the present invention, a radial load and a moment load are applied by the guide rolling element, so that the distance between the tapered surface of the clamper rolling element and the raceway shaft does not fluctuate, and a stable high holding force is maintained. can do.

BRIEF DESCRIPTION OF THE DRAWINGS The clamper with a linear motion guide which concerns on embodiment of this invention is shown, (A) is a longitudinal cross-sectional view, (B) is a front view, (C) is an enlarged view of the rolling part for a clamp. Operation | movement explanatory drawing of the clamper with a linear motion guide of FIG. (A) is a longitudinal cross-sectional view of the clamper with a linear motion guide which concerns on other embodiment of this invention, (B) is a longitudinal cross-sectional view of another form, (C) is a front view. The example which provided the groove | channel where the ball for guides rolls in the outer cylinder and track shaft of embodiment of FIG. 1 is shown, (A) is a longitudinal cross-sectional view, (B) is a front view.

Hereinafter, a clamper with linear motion guide according to an embodiment of the present invention will be described in detail with reference to the drawings.
[Embodiment 1]
FIG. 1 shows a clamper with linear motion guide according to Embodiment 1 of the present invention.
The linear guide clamper 1 includes an axial shaft 30 extending in the axial direction, an outer cylinder 10 having a tapered surface 22 inserted into the axial shaft 30 and facing the axial shaft 30, and a tapered surface of the outer cylinder 10. The rolling element 4 for clamping clamped between 22 and the track shaft 30, the holder 40 for holding the rolling element 4 for clamping, and the outer cylinder 10 and the holder 40 are provided, and the rolling element 4 for clamping is tapered. And a spring 60 as an urging member that urges the surface 22 in the direction of biting.

In addition, the outer cylinder 10 is provided with a plurality of axially extending load ball rolling surfaces 3 with which a plurality of guiding balls 2 as rolling elements for guiding are in contact with each other in a freely rolling manner, in this example, four strips. The cage 40 is provided with a circulation path 50 for circulating the guide ball 2 from one end of the load ball rolling surface 3 to the other end.
The guide ball 2 disposed between the outer cylinder 10 and the track shaft 30 and the retainer 40 that holds the guide ball 2 constitute a ball bush as a linear motion guide mechanism.
The track shaft 30 is a round shaft whose outer peripheral surface is a cylindrical surface, and does not need to have a particularly precise machining surface.

  The outer cylinder 10 is a cylindrical member, and a plurality of concave surface portions 12 having an arcuate cross section are formed between the respective load ball rolling surfaces 3 in the circumferential direction. The load ball rolling surface 3 is provided so that, for example, a circle drawn around a point equidistant on a straight line passing through the center of the load ball 2 from the central axis of the outer cylinder 10 is inscribed, and the center of the concave surface portion 12 is provided. Is farther from the central axis of the outer cylinder 10 than the center of the inscribed circle. The loaded ball rolling surface 3 may be a circular arc groove having an arc cross section or a gothic arch groove.

On the other hand, the axial length of the load ball rolling surface 3 is shorter than the length of the outer cylinder 10, and the end thereof is separated from the cylinder end position of the outer cylinder 10 by a predetermined distance.
The tapered surfaces 22 and 23 are formed so as to gradually increase in diameter from both ends of the load ball rolling surface 3 toward both cylinder ends of the outer cylinder 10. The tapered surfaces 22 and 23 have a tapered shape for allowing the guide ball 2 to circulate to the concave surface portion 12 side. By using this tapered shape, the rolling element 4 for clamping is provided on one tapered surface 22 side. It is in contact.
The tapered surface 22 on the side on which the rolling element for clamping 4 abuts is formed with a cylindrical protruding portion 14 that protrudes in a cylindrical shape by a predetermined length from the end of the tapered surface 22. The inner diameter of the protruding portion 14 is equal to the maximum diameter of the concave surface portion 12.

As the rolling element 4 for clamping, a good roller is used as shown in an enlarged view in FIG.
The good roller has a cross-sectional shape cut along a plane passing through the central axis, and a cross-sectional shape cut along a plane passing through the central axis of the central concave surface portion 4a and the central concave surface portion 4a. Has an arcuate and convex end convex surface portion 4b.
The end convex surface portion 4 b is in line contact with the tapered surface 22, and the central concave surface portion 4 a is in line contact with the track shaft 30 so as to roll freely.

As described above, when a good roller is used as the rolling element 4 for clamping, the contact area is increased due to line contact, so that the friction torque is increased and the gripping force can be increased. Further, the rotational movement of the track shaft 30 can be suppressed by friction caused by surface contact between the track shaft 30 and the central concave surface portion 4a of the good roller.
Of course, the rolling element 4 for clamping is not limited to a good roller, but may be a ball, a spherical roller, or a cylindrical roller in some cases. Various rolling elements can be used depending on the structure and shape of the mechanism.

The cage 40 can move in the axial direction relative to the outer cylinder 10, and the clamping rolling element 4 can move in a direction away from the direction of biting into the tapered surface 22 via the cage 40. It has become.
The cage 40 has a cylindrical shape, and has an arc-shaped convex surface portion 42 corresponding to the concave surface portion 12 of the inner peripheral surface of the outer cylinder 10 on the outer peripheral side. It is assembled so that it cannot move relative to the direction. A long hole 52 a that extends in the axial direction constituting the load ball passage 52 is opened on the surface on the track shaft 30 side corresponding to the load ball rolling surface 3.
Further, an unloaded ball passage 54 extending in parallel with the loaded ball passage 52 is formed on the outer peripheral side of the cage 40 at a position corresponding to the concave surface portion 12 with respect to the loaded ball passage 52, and the loaded ball passage 52 and the unloaded ball are formed. A direction change path 56 that connects both ends of the passage 54 in a U-shape is provided. A cutout is formed on the inner peripheral side of the direction change path 56 on the load ball path 52 side. A large number of ball rows are mounted on each circulation path 50, and the guide balls 2 circulate and move as the track shaft 30 and the outer cylinder 10 move relative to each other.

Therefore, the ball train of the guide balls 2 is disposed so as to surround the track shaft 30 at four locations 90 ° apart in the circumferential direction, and receives a load in four directions, up, down, left, and right. . The outer cylinder 10 has a degree of freedom in the rotation direction with respect to the track shaft 30.
Between the retainer 40 and the outer cylinder 10, a spring 60 is disposed as a biasing member that biases the clamping rolling element 4 in the direction of biting the tapered surface 22. One end of the spring 60 is engaged with a spring seat 62 provided on the outer cylinder 10, and the other end is engaged with a spring seat 64 on the cage 40 side.
On the other hand, the other end of the cage 40 can be pushed in the direction of separating the rolling element 4 for clamping from the tapered surface 22 via the cage 40 against the spring force of the spring 60.

Next, the operation of the clamper with linear motion guide will be described with reference to FIG.
In the free state, the rolling element 4 for clamping is in contact with the tapered surface 22 by the spring force of the spring 60, and the outer cylinder 10 and the track that move in a direction in which the rolling element 4 for clamping is engaged with the tapered surface 22. Relative movement between the shafts 30 is restricted, and relative movement in the opposite direction is allowed (see FIGS. 2B and 2C). This relative movement is guided by a guide ball that circulates indefinitely. Since the form is a ball bush, relative rotation between the outer cylinder 10 and the track shaft 30 is allowed.
On the other hand, as shown in FIGS. 2 (A) and 2 (C), if the cage 40 is moved in a direction in which the rolling element 4 for clamping is moved away from the tapered surface 22, an unclamped state is established, and both axial directions are performed. It can move freely. Similarly, the unclamped state may be achieved by moving the outer cylinder 10 relative to the retainer 40 in a direction in which the rolling element 4 for clamping moves away from the tapered surface 22.

  Since the radial load and the moment load are applied by the guide ball 2, the distance between the taper surface 22 and the raceway shaft 30 is maintained, and the holding force of the rolling element for clamping 4 is not adversely affected. The positional deviation of the moving body 4 can be prevented. As a result, the clamping rolling element 4 is correctly bitten into the tapered surface 22, and a stable clamping state can be maintained with a high holding force.

Furthermore, since the rolling element 4 for clamping is a good roller, the contact between the raceway shaft 30 and the rolling element 4 for clamping, and the contact between the rolling element 4 for clamping and the tapered surface of the outer cylinder 10 becomes surface contact, and a large holding force is obtained. can get.
Although the clamper with linear guide of this embodiment is a one-way clamper, the use of two clampers can be configured to restrict movement in both directions.

Although not shown in particular, a clamper with a linear guide in both directions can be configured by using the tapered surface 23 on the other end side of the outer cylinder 10 and providing the rolling elements 4 for clamping at both ends.
In each of the above embodiments, the tapered surface has a conical shape, but may be a flat surface.

[Other embodiments]
Next, a linear motion guide clamper according to another embodiment of the present invention will be described with reference to FIG. The basic configuration is the same as that of the first embodiment, and the embodiment of FIG. 3 is mainly different only in the structure of the outer cylinder 10. Therefore, only the differences will be described in the following description, and the same components will be described. Are denoted by the same reference numerals, and the description thereof is omitted.

In this embodiment, the outer cylinder 10 has an outer cylinder body 11 that is a first outer cylinder portion provided with a load ball rolling surface 3 of the guide ball 2, and an axial direction on one axial end side of the outer cylinder body 11. And a tapered ring 13 as a second outer cylinder portion that is assembled so as to be movable. The retainer 40 is fixed so as not to move relative to the outer cylinder body 11 in the axial direction, and the taper ring 13 is urged by a spring 60 as an urging member , and the conical tapered surface 22 of the taper ring 13 is urged. The rolling element 4 for clamping is pressed.
There are two types of fixing of the retainer 40 to the outer cylinder main body 11, FIG. 3 (A) is fixed by two retaining rings, and FIG. 3 (B) is fixed to the outer cylinder main body 11 by pins 15. It is a form. The pin 15 is fixed to the convex surface portion of the cage.

The procedure for assembling the linear motion guide clamper according to the second embodiment is as follows.
i) The rolling element 4 for clamping is mounted in the holding hole 40c of the holder 40.
ii) The taper ring 13 is combined with a cage 40 that holds the rolling element 4 for clamping.
iii) A spring 60 is attached to the assembly of the taper ring 13, the rolling element 4 for clamping, and the retainer 40.
iv) A washer is put into the assembly of the taper ring 13, the rolling element 4 for clamping, the retainer 40 and the spring 60.
v) Place the guide ball 2 in the cage 40.
vi) Finally, from the outer peripheral side of the outer cylinder main body 11, it is fixed with a retaining ring as shown in FIG. 3A, or the cage 40 is fixed with a pin 15 as shown in FIG.

FIG. 4 shows an example in which the linear motion guide of the first embodiment is changed from a ball bush structure to a ball spline structure, and a spline groove 32 corresponding to the loaded ball rolling surface 3 of the outer cylinder 10 is formed on the outer periphery of the raceway shaft 30. It is a thing. By engaging with the spline groove, the outer cylinder 10 and the track shaft 30 have no degree of freedom of rotation around the central axis.
Since the spline groove 32 is formed in the outer cylinder 10, the width of the central concave surface portion 4 a of the rolling element 4 for clamping is set larger than the width of the spline groove 32, and the central concave surface portion 4 a is on both sides of the spline groove 32. It will contact the edge.

  Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the embodiment shown in FIG. 3, the retainer 40 is fixed by the pin 15. However, in the embodiment shown in FIGS. 1 and 4, the retainer 40 is provided with a long hole in the axial direction, and The moving stroke of the cage 40 can be restricted by the fixed pin 15. In this case, it is possible to prevent the retainer 40 from coming off even when the track shaft 30 is not inserted into the outer cylinder 10.

DESCRIPTION OF SYMBOLS 1 Clamper with linear guide 2 Guide ball 3 Rolling surface of loaded ball 4 Rolling body for clamp 4a Central concave part, 4b End convex part,
DESCRIPTION OF SYMBOLS 10 Outer cylinder, 12 Concave part, 14 Protrusion part 11 Outer cylinder main body 13 Taper ring 15 Pin 22 Tapered surface 30 Track shaft 32 Spline groove 40 Cage 40c Holding hole, 42 Convex part 50 Circulation path, 52 Load ball path, 52a Long Hole, 54 Unloaded ball passage 56 Direction change path 60 Spring, 62 Spring seat, 64 Spring seat

Claims (4)

An axially extending track shaft,
An outer cylinder inserted into the raceway shaft and having a tapered surface facing the raceway shaft;
A rolling element for clamping sandwiched between the tapered surface of the outer cylinder and the raceway shaft;
A cage for holding the rolling element for clamping;
An urging member that is provided between the outer cylinder and the cage and urges the rolling element for clamping in a direction to bite into the tapered surface;
The outer cylinder is provided with a plurality of rolling element rolling surfaces extending in the axial direction in which a large number of rolling elements for guide contact in a freely rolling manner, in the circumferential direction,
The retainer is provided with a circulation path that holds the rolling element for guidance and circulates from one end of the rolling element rolling surface to the other end,
The cage can be moved in the axial direction with respect to the outer cylinder, and the urging member is urged against the outer cylinder by the urging member , so that the clamping rolling element is attached in a direction to be engaged with the tapered surface. A clamper with a linear motion guide characterized by An axially extending track shaft,
An outer cylinder inserted into the raceway shaft and having a tapered surface facing the raceway shaft;
A rolling element for clamping sandwiched between the tapered surface of the outer cylinder and the raceway shaft;
A cage for holding the rolling element for clamping;
An urging member that is provided between the outer cylinder and the cage and urges the rolling element for clamping in a direction to bite into the tapered surface;
The outer cylinder is provided with a plurality of rolling element rolling surfaces extending in the axial direction in which a large number of rolling elements for guide contact in a freely rolling manner, in the circumferential direction,
The retainer is provided with a circulation path that holds the rolling element for guidance and circulates from one end of the rolling element rolling surface to the other end,
The outer cylinder is divided into a first outer cylinder part having a rolling element rolling surface of the rolling element for guidance and a second outer cylinder part assembled to the first outer cylinder part so as to be movable in the axial direction. ,
The clamp with linear motion guide, wherein the cage is fixed so as not to move relative to the first outer cylinder portion in the axial direction, and the second outer cylinder portion is urged by the urging member . The clamper with a linear motion guide according to claim 1 or 2, wherein the rolling element for clamping is a good roller.   The clamp with linear motion guide according to any one of claims 1 to 3, wherein the outer cylinder and the raceway shaft are provided with grooves for rolling the rolling elements for guidance.