JP5654432B2 - Positioning device - Google Patents

Description

  The present invention relates to a positioning device such as a ball plunger or a clamping screw used for positioning and fixing a workpiece on a table of a machine tool, for example.

  The ball plunger is provided with a coil spring accommodating portion that opens on the tip end side, and the ball is supported by the coil spring in the coil spring accommodating portion so as to be freely rotatable. A part of the ball is exposed from the ball housing portion and comes into contact with the workpiece. When positioning the workpiece using this ball plunger, the ball plunger is screwed into the screw hole of the ball plunger support disposed near the table supporting the workpiece, and the ball contacts the workpiece. Let In this state, the work can be positioned at a predetermined position by moving the work and engaging the ball plunger ball with the positioning recess of the work.

  Such a ball plunger mechanism is described in Patent Document 1, for example. The ball plunger mechanism includes a ball pressed against an object, a ball storage hole for storing the ball, a narrow overflow portion formed at an opening end of the ball storage hole, and presses the ball against the narrow overflow portion. And a spring member, wherein a part of the ball protrudes from the narrow overflow portion. The hole diameter of the ball storage hole is set to a value larger than the diameter of the ball so that the ball moving inside the ball storage hole does not contact the inner wall of the ball storage hole when the ball plunger mechanism is operated.

  On the other hand, the clamping screw has a conical hole-shaped ball receiving portion recessed at the tip thereof, and the ball is supported by the ball receiving portion so as to be freely rotatable. A part of the ball is exposed from the ball housing portion and comes into contact with the workpiece. Then, using this clamping screw, the workpiece can be positioned at a predetermined position in the same manner as the ball plunger.

  Such a clamping screw is disclosed in Patent Document 2, for example. Such a clamping screw includes a clamping screw main body provided with a ball housing portion at a tip thereof, a ball that is freely rotatable in the ball housing portion, a part of which protrudes from the ball housing portion, and a ball housing And supporting means for supporting the ball at one point on the rotational axis of the clamping screw main body. When the clamping screw is strongly tightened against the workpiece, the ball is supported by the point by the support means, and therefore the rotational force of the clamping screw body is not transmitted to the ball. For this reason, the clamping screw main body can be smoothly rotated, and the workpiece does not rotate in conjunction with the rotation of the clamping screw main body, and there is no possibility of shifting from the position.

JP 2000-285527 A JP-A-7-217616

  By the way, the positioning device such as the ball plunger or the clamping screw may be used by being placed in a vacuum atmosphere in which a workpiece to be positioned is decompressed to a predetermined degree of vacuum. In this case, the ball receiving portion, the ball plunger, or the tool locking hole for screwing the clamping screw into the screw hole of the support member is blocked from the outside and is not exposed to the vacuum atmosphere. Even in the conventional configurations described in Patent Documents 1 and 2, the ball plunger, the ball accommodating portion of the clamping screw, the tool locking hole, and the like are not exposed to the vacuum atmosphere in a vacuum atmosphere, and remain in the atmospheric pressure atmosphere. .

  For this reason, when the clamping screw and the ball plunger are used in a vacuum atmosphere such as a film forming apparatus that performs processing at high vacuum, the air present in the tool locking hole in the ball accommodating portion of the clamping screw or the ball plunger is removed. The vacuum gradually leaks into the vacuum, and the vacuum degree of the vacuum atmosphere gradually decreases. Therefore, it is not possible to maintain an appropriate degree of vacuum in the processing process, and there is a possibility that the quality of the product to be produced will be adversely affected.

  The present invention has been made paying attention to such problems existing in the prior art, and the object of the present invention is to eliminate the portion that is not exposed to vacuum when used in a vacuum atmosphere, and to reduce the degree of vacuum. An object of the present invention is to provide a positioning device that can be maintained at a predetermined value.

In order to achieve the above object, a positioning device according to a first aspect of the present invention includes a main body having a ball housing portion provided at a tip thereof, and is housed in the ball housing portion, a part of which is outside the ball housing portion. The positioning device includes a protruding ball and a ball support portion provided in the ball housing portion and supporting the ball, and the ball is engaged with an engagement portion of the object to position the object. In addition, a degassing opening that communicates the inside of the ball housing portion from the distal end side to the outside is formed on the distal end side of the main body, and a shielding portion in the main body is communicated with the degassing opening portion on the proximal end side of the main body. the venting holes communicating with the outside from the base end side or tip side formed through, characterized in that it is used in a vacuum atmosphere.

  According to a second aspect of the present invention, there is provided the positioning device according to the first aspect, wherein the gas vent opening is formed by a slit cut out along the axial direction of the main body at the tip of the main body. Features.

According to a third aspect of the present invention, there is provided the positioning device according to the second aspect, wherein a pair of the slits are provided at positions opposed to each other by 180 degrees.
According to a positioning device of a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the gas vent hole extends in the axial direction of the main body at a center position of the base end of the main body. It is characterized by being formed through.

  A positioning device according to a fifth aspect of the present invention is the positioning device according to any one of the first to fourth aspects, wherein the gas vent hole is formed with a tool locking hole and a ball formed at the base end of the main body. A through-hole is formed so as to communicate with the inside of the housing portion.

  A positioning device according to a sixth aspect of the present invention is the positioning device according to any one of the first to fifth aspects, wherein the ball is provided with a notch, and the notch is external to the ball receiving portion. And is configured to engage with an engaging portion of the object.

According to the present invention, the following effects can be exhibited.
The positioning device of the present invention includes a main body provided with a ball housing portion at a tip, a ball housed in the ball housing portion, a part of which protrudes to the outside from the ball housing portion, and the ball housing portion. And a ball support portion for supporting the ball. A degassing opening that communicates the inside of the ball housing portion from the distal end side to the outside is formed on the distal end side of the main body, and a shielding portion in the main body that communicates with the degassing opening portion on the proximal end side of the main body. gas vent holes communicating with the outside from the base end side or tip side is formed through, and is used in a vacuum atmosphere to.

  For this reason, when the positioning device is used in a vacuum atmosphere, the air in the ball housing portion is drawn out from the gas vent opening to the outside, and at the same time, the air is drawn out from the ball housing portion through the gas vent hole. . Therefore, in addition to the air present in the ball housing portion of the positioning device, for example, air present in the tool locking hole provided in the base end portion of the main body can be extracted to the outside through the gas vent hole. it can.

  Therefore, according to the positioning device of the present invention, when used in a vacuum atmosphere, there is an effect that a portion that is not exposed to vacuum can be eliminated and the degree of vacuum can be maintained at a predetermined value.

Sectional drawing which shows the use condition of the ball plunger in embodiment of this invention. (A) is a front view which shows a ball plunger, (b) is a right view which shows a ball plunger, (c) is a left view which shows a ball plunger. Sectional drawing which shows the use condition of a clamping screw. (A) is a front view showing a clamping screw, (b) is a right side view showing a clamping screw, and (c) is a left side view showing a clamping screw. Sectional drawing which shows the use condition of the clamping screw as another example.

(First embodiment)
Hereinafter, a first embodiment in which the positioning device of the present invention is embodied as a ball plunger will be described in detail with reference to FIGS. 1 and 2.

  As shown in FIGS. 1 and 2A, a ball plunger 10 as a positioning device has a main body 11 formed of stainless steel in a substantially cylindrical shape, and a male screw 11a is threaded on the outer peripheral surface of the main body 11. Yes. And it is comprised so that the ball plunger 10 may be attached to the table 12 by screwing in the internal thread 13a formed in the holding hole 13 of the table 12 of a machine tool as a support tool of the ball plunger 10, for example. A frustoconical ball accommodating portion 14 is provided at the tip of the main body 11, and a stainless steel ball 15 is accommodated in the ball accommodating portion 14. The outer end portion of the ball housing portion 14 is caulked toward the inner peripheral side along the ball 15, and serves as a regulation edge 14 a that regulates the falling of the ball 15. A part of the ball 15 accommodated in the ball accommodating portion 14 protrudes outward from the restriction edge 14a.

  A circular spring accommodating hole 16 extending in the axial direction of the main body 11 is recessed at the center position in the main body 11, and a coil spring 17 as a ball support portion is accommodated in the spring accommodating hole 16. The inner end portion of the coil spring 17 is supported by the bottom wall 16a of the spring accommodating hole 16, and the outer end portion supports the ball 15. The coil spring 17 biases the ball 15 outward. It is configured as follows.

  As shown in FIGS. 2 (a) and 2 (b), a slit 18 as a degassing opening communicating with the inside of the ball housing portion 14 from the tip side to the outside is located at a position facing the tip of the main body 11 180 degrees. A pair is provided. Both slits 18 are cut out along the axial direction of the main body 11 so that the air in the ball housing portion 14 is extracted to the outside in a vacuum atmosphere.

  As shown in FIGS. 2A and 2C, a hexagonal hole-shaped tool locking hole 19 is recessed at the center position of the base end surface of the main body 11, and a hexagon wrench is engaged with the tool locking hole 19. And the ball plunger 10 is rotated. A circular gas vent hole 20 is formed in the base end side of the main body 11 in the axial direction of the main body 11 so as to communicate the inside of the tool locking hole 19 and the inside of the ball accommodating portion 14. And the air in the tool locking hole 19 is extracted from the inside of the ball accommodating part 14 through the slit 18 through the gas vent hole 20 to the outside. Further, depending on how the ball plunger 10 is used, the air in the ball accommodating portion 14 is extracted from the tool locking hole 19 to the outside through the gas vent hole 20.

Next, the operation of the ball plunger 10 configured as described above will be described.
Now, as shown in FIG. 1, a hexagon wrench (not shown) is engaged in the tool locking hole 19 of the ball plunger 10, and the male screw 11 a of the main body 11 of the ball plunger 10 is screwed into the female screw 13 a of the holding hole 13 of the table 12. By doing so, it fixes so that the front-end | tip part of the ball plunger 10 may become flush with the table 12 surface. At this time, a part of the ball 15 of the ball plunger 10 is exposed outward from the surface of the table 12 while being biased by the coil spring 17. On the other hand, as shown by a two-dot chain line in FIG. 1, a workpiece 21 as an object is movably disposed on the table 12, and a positioning concave portion 22 having a triangular cross section as an engaging portion of the workpiece 21 is a ball plunger 10. The workpiece 21 is positioned by engaging with the ball 15.

  When the workpiece 21 is used in a vacuum atmosphere, the ball plunger 10 is also exposed to the vacuum atmosphere. At this time, the air present in the ball accommodating portion 14 of the ball plunger 10 is extracted to the outside from the pair of slits 18, but the air present in the tool locking hole 19 on the proximal end side of the ball plunger 10 is conventionally Then, since it is shielded by the main body 11 of the ball plunger 10 in the holding hole 13 of the table 12, it is in a state where it is difficult to come out to the outside. In addition, the inside of the holding hole 13 inside the main body 11 of the ball plunger 10 is in a sealed state.

  However, in the ball plunger 10 of the first embodiment, a gas vent hole 20 is formed through the ball accommodating portion 14 and the tool locking hole 19. For this reason, the air existing in the tool locking hole 19 and the spring accommodation hole 16 passes through the gas vent hole 20 to reach the ball accommodation portion 14 from the spring accommodation hole 16, and further from the inside of the ball accommodation portion 14 to the slit 18. Flows to the space on the workpiece 21 side. Therefore, there is no possibility that the air accumulated in the shielding portion of the ball plunger 10 gradually leaks when the work 21 is used and the vacuum degree is lowered, and the vacuum degree of the work 21 in the vacuum atmosphere is maintained at a predetermined value.

The effects exhibited by the first embodiment described in detail above will be collectively described below.
(1) In the ball plunger 10 of the first embodiment, a slit 18 is formed on the distal end side of the main body 11 so as to communicate the inside of the ball housing portion 14 from the distal end side to the outside, and on the proximal end side of the main body 11. A gas vent hole 20 is formed through the ball accommodating portion 14 so as to communicate with the outside from the base end side. For this reason, when the ball plunger 10 is used in a vacuum atmosphere, the air in the tool locking hole 19 passes through the slits 18 together with the air in the ball accommodating part 14 from the gas vent hole 20 through the spring accommodating hole 16. Pulled out.

Therefore, according to the ball plunger 10 of the first embodiment, when used in a vacuum atmosphere, it is possible to eliminate the portion that is not exposed to the vacuum and to exhibit the effect that the degree of vacuum can be maintained at a predetermined value. .
(2) The gas vent opening is formed by a slit 18 cut out along the axial direction of the main body 11 at the tip of the main body 11. For this reason, while being able to simplify the structure of a gas vent opening part, air can be smoothly extracted to the outward of the axial direction of the main body 11. FIG.
(3) A pair of the slits 18 are provided at positions facing each other by 180 degrees. Therefore, the air in the ball accommodating portion 14 in the ball plunger 10 can be quickly extracted with good balance.
(4) The gas vent hole 20 is formed so as to extend in the axial direction of the main body 11 at the center position of the base end of the main body 11. Therefore, the air existing on the base end side of the main body 11 or the air existing on the front end side of the main body 11 can be effectively and quickly extracted to the outside on the opposite side through the gas vent hole 20 at the center of the main body 11.
(5) The gas vent hole 20 is formed so as to communicate between the inside of the tool locking hole 19 formed at the base end of the main body 11 and the inside of the ball housing portion 14. For this reason, the air in the tool locking hole 19 can be guided into the ball housing portion 14, and the air in the ball housing portion 14 can be guided into the tool locking hole 19. Or it can extract to the exterior of a base end side.
(Second Embodiment)
Hereinafter, a second embodiment in which the positioning device of the present invention is embodied in a clamping screw will be described in detail with reference to FIGS. The second embodiment will be described with a focus on differences from the first embodiment.

  As shown in FIGS. 3 and 4A, the clamping screw 30 is formed to be longer than the ball plunger 10, and the ball support portion is not provided at the coil spring 17 but is recessed at the distal end portion of the main body 31. And a ball receiving surface 32. As shown in FIGS. 4A and 4B, the pair of slits 18 is formed so as to be deeper than the ball receiving surface 32, and is configured so that air in the ball housing portion 14 can escape to the outside. Yes. As shown in FIGS. 4A and 4C, an inclined surface 19 a is provided at the bottom of the tool locking hole 19.

  When the clamping screw 30 is used in a vacuum atmosphere, as shown in FIG. 3, a hexagon wrench (not shown) is engaged in the tool locking hole 19 of the clamping screw 30, and the main body of the clamping screw 30. The male screw 31a of 31 is screwed into the female screw 34a of the holding hole 34 of the holding body 33 as a support. By this operation, the front end portion of the main body 31 of the clamping screw 30 is fixed so as to be flush with the end surface of the holding body 33. At this time, a part of the ball 15 of the clamping screw 30 is exposed outward from the end face of the holding body 33. On the other hand, as shown by a two-dot chain line in FIG. 3, the work 21 is arranged so as to be movable with respect to the holding body 33, and the ball 15 of the clamping screw 30 with respect to the target surface 36 as the engaging portion of the work 21. Is pressed to position the workpiece 21.

  When the workpiece 21 is exposed to a vacuum atmosphere, the workpiece 21 side of the clamping screw 30 is exposed to a vacuum atmosphere. At this time, the air present in the ball accommodating portion 14 of the clamping screw 30 is extracted to the outside from the pair of slits 18, but the air present in the tool locking hole 19 on the proximal end side of the clamping screw 30 is Conventionally, since it is shielded by the main body 31 of the clamping screw 30 in the holding hole 34 of the holding body 33, it is difficult to come out to the outside. However, in the clamping screw 30 of the second embodiment, a pair of slits 18 that communicate with the outside of the ball housing portion 14 are provided on the tip side, and the inside of the ball housing portion 14 and the tool locking hole 19 are provided. A gas vent hole 20 is formed therethrough.

  For this reason, the air in the tool locking hole 19 passes through the gas vent hole 20 and reaches the ball accommodating portion 14, and further flows out from the ball accommodating portion 14 through the slit 18 to the space portion on the workpiece 21 side. Therefore, there is no possibility that air leaks from the shielding part of the clamping screw 30 when the work 21 is used and the vacuum degree is lowered, and the vacuum degree in the vacuum atmosphere of the work 21 is maintained.

  Therefore, according to the clamping screw 30 of 2nd Embodiment, while being able to exhibit the effect similar to 1st Embodiment, the workpiece | work 21 can be positioned with a simple structure.

It should be noted that the above-described embodiments may be modified as follows.
As shown in FIG. 5, a notch surface 35 that is notched flat may be provided as a notch at the tip of the ball 15 of the clamping screw 30. In this case, the holding hole 34 of the holding body 33 extends in an oblique direction, and the clamping screw 30 is screwed therein. The notch surface 35 of the ball 15 protrudes outside from the ball housing portion 14 and is configured to engage with a target surface 36 as an engaging portion of the workpiece 21. Note that the size of the notch surface 35 of the ball 15 can be appropriately set according to the type of the workpiece 21, the inclination angle of the clamping screw 30, and the like.

  Therefore, when the notch surface 35 is provided on the ball 15, the axis of the holding hole 34 of the holding body 33, that is, the axis of the clamping screw 30 extends obliquely with respect to the target surface 36 of the work 21. The contact area of the notch surface 35 of the ball 15 with respect to the surface 36 can be increased, and the workpiece 21 can be positioned effectively.

The slit 18 as the degassing opening can be constituted by one, or can be constituted by three or more.
The gas vent opening may be configured as a through hole that opens to the outside in the ball housing portion 14 at the distal end portions of the main bodies 11 and 31.

The gas vent holes 20 may be provided at a plurality of locations so as to communicate the inside of the ball housing portion 14 and the inside of the tool locking hole 19.
A spacer may be interposed between the ball 15 and the coil spring 17 so that the ball 15 can be rotated smoothly.

  The ball 15 can be formed of ceramic, synthetic resin, or the like.

  DESCRIPTION OF SYMBOLS 10 ... Ball plunger as a positioning device, 11 ... Main body, 14 ... Ball accommodating part, 15 ... Ball, 17 ... Coil spring as a ball support part, 18 ... Slit as a degassing opening part, 19 ... Tool locking hole, DESCRIPTION OF SYMBOLS 20 ... Gas vent hole, 21 ... Workpiece | work as target object, 22 ... Positioning recessed part as an engaging part, 30 ... Clamping screw as a positioning device, 31 ... Main body, 32 ... Ball receiving surface as a ball support part, 35 ... notch surface as notch, 36 ... target surface as engagement part.

Claims (6)

A main body provided with a ball housing portion at the tip, a ball housed in the ball housing portion, a part of which protrudes to the outside from the ball housing portion, and a ball support that is provided in the ball housing portion and supports the ball A positioning device for positioning the target object by engaging the ball with the engaging part of the target object,
A degassing opening that communicates from the distal end side to the outside is formed on the distal end side of the main body, and a degassing opening portion that communicates with the degassing opening portion on the proximal end side of the main body. A positioning apparatus characterized in that a gas vent hole communicating with the outside from the end side or the front end side is formed so as to be used in a vacuum atmosphere . The positioning device according to claim 1, wherein the gas vent opening is formed by a slit cut out along an axial direction of the main body at a tip of the main body. The positioning device according to claim 2, wherein a pair of the slits are provided at positions opposed to each other by 180 degrees. The positioning device according to any one of claims 1 to 3, wherein the gas vent hole is formed so as to extend in the axial direction of the main body at a central position of a base end of the main body. . 5. The gas venting hole according to claim 1, wherein the gas venting hole is formed so as to communicate with a tool locking hole formed at a base end of the main body and the inside of the ball housing portion. The positioning device according to item. The notch part is provided in the said ball | bowl, This notch part protrudes outside from a ball | bowl accommodating part, It is comprised so that it may engage with the engaging part of a target object. The positioning device according to claim 5.

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