JP6018942B2 - Clamping device and clamping system using the clamping device - Google Patents

Description

  The present invention relates to an apparatus for clamping an object to be fixed to a fixed side member such as a base plate by engaging an engagement member with an inner peripheral surface of a hole formed in the object to be fixed such as a workpiece or a mold. In other words, the present invention relates to a technique for positioning and clamping the fixed object on a fixed side member.

  As this type of clamping device with a positioning function, there is one described in Patent Document 1 (Japanese Patent Laid-Open No. 2010-137343 (published on June 24, 2010)). The prior art is configured as follows.

  A piston is inserted into a cylinder hole provided in a clamp body as a housing so as to be vertically movable. A clamp rod (output rod) is connected to the piston so as to be horizontally movable. A grip member (engagement member) is externally fitted to the upper part of the clamp rod, and a hole of a workpiece can be fitted to the grip member from above. A fitting recess for positioning is formed in the workpiece below the hole. A fitting portion that fits into the fitting recess and positions the workpiece in the horizontal direction is formed at the upper end portion of the clamp body on the outer peripheral side of the grip member.

JP 2010-137343 A (released on June 24, 2010)

  Although the above-mentioned prior art connects the clamp rod to the piston so that it can move horizontally, it can absorb the misalignment between the grip member fitted on the clamp rod and the hole of the workpiece, but has the following problems.

  Since the fitting part provided in the upper part of the clamp main body is fitted with the fitting concave part of the workpiece, it is necessary to protrude upward from the clamp main body and to be opened to the outside. For this reason, there is a possibility that foreign matters such as dust and chips generated during machining of the workpiece may be caught between the fitting portion and the fitting recess, thereby deteriorating the positioning function of the clamping device.

  Moreover, since it is necessary to process a fitting recessed part in the said workpiece | work, the process takes time.

  An object of the present invention is to provide a clamp device that can prevent a positioning function from being lowered due to the biting of a foreign substance and reduce processing applied to an object to be fixed such as a workpiece. Another object of the present invention is to provide a clamping system using the clamping device.

  In order to achieve the above object, the clamping device of the present invention is configured as follows, for example, as shown in FIGS. 1, 2A and 2B.

  That is, the piston 12 is inserted into the cylinder hole 11 provided in the housing 2 so as to be movable in the axial direction. The output rod 15 is integrally projected from the piston 12 in the distal direction. On the outer peripheral side of the output rod 15, an engagement member 20 that can be engaged with the hole 18 of the fixed object 17 is disposed so as to be interlocked with the output rod 15. A pair of protrusions 70 and 70 (72, 72) fitted in the cylinder hole 11 are provided on the outer peripheral surface of the piston 12 so as to face each other with the axis C therebetween. A pair of relief portions 71, 71 (73, 73) are formed between the pair of protrusions 70, 70 (72, 72) so as to extend in the circumferential direction.

  Here, the term “integrally” refers to a case where both the piston and the output rod are integrally formed, and a case where the both are formed separately and the both are fixed by screwing or the like. Conceivable.

  The clamping device of the present invention has the following effects.

  When positioning the clamping device, a gap between the cylinder hole of the housing and the protrusion provided on the piston functions as a fitting gap for positioning. Therefore, the piston is positioned with respect to the cylinder hole in a direction in which the pair of protrusions face each other. For this reason, a to-be-fixed object can be positioned with respect to the said housing via the output rod and the engaging member which were integrally protruded from the piston. The pair of relief portions formed between the pair of projections functions to absorb positioning errors in the direction in which the pair of relief portions face each other.

  In addition, the positioning fitting gap formed between the cylinder hole and the projection is disposed in the housing, so that foreign matter such as dust and chips generated during machining is prevented from being caught. it can. For this reason, the positioning function of the clamping device can be maintained well over a long period of time. Furthermore, the present invention, unlike the above-described prior art, eliminates the need to process the fitting recess in the object to be fixed, and therefore can reduce the processing applied to the object to be fixed.

  In the invention, at least one of the large-diameter portion 13 provided on the proximal end side of the piston 12 and the small-diameter portion 14 provided on the distal end side of the piston 12 is provided with the pair of protrusions 70 and 70 (72 and 72). ).

  In the present invention, it is preferable that the pair of protrusions 70 and 70 are provided on the large diameter portion 13 and the pair of protrusions 72 and 72 are also provided on the small diameter portion 14. According to this configuration, the axial length between the pair of protrusions formed on the large diameter portion of the piston and the pair of protrusions formed on the small diameter portion of the piston is large. The piston can be supported in the cylinder hole. For this reason, the inclination of a piston and an output rod can be made small, and positioning accuracy can be improved more.

  Moreover, in the said invention, it is preferable to comprise as follows.

  That is, the cylinder hole 11 has a large-diameter hole 11a provided on the proximal end side and a small-diameter hole 11b provided on the distal end side. The pair of protrusions 70 are provided on the first large-diameter portion 53 formed on the proximal end side of the large-diameter portion 13. A first gap G1 formed between the protruding portion 70 and the large diameter hole 11a is defined between the second large diameter portion 54 formed on the distal end side of the large diameter portion 13 and the large diameter hole 11a. Is set to a value smaller than the second gap G <b> 2 formed. The pair of protrusions 72 and 72 are provided on the first small diameter portion 58 formed on the distal end side of the small diameter portion 14. A third gap G3 formed between the projection 72 and the small diameter hole 11b is formed between the second small diameter part 59 formed on the proximal end side of the small diameter part 14 and the small diameter hole 11b. The value is set to be smaller than the fourth gap G4.

  According to this configuration, the axial length between the pair of protrusions formed on the first large diameter portion of the piston and the pair of protrusions formed on the first small diameter portion of the piston is further increased. Therefore, the piston can be supported in the cylinder hole at the large distance. For this reason, the inclination of the piston and the output rod can be further reduced to further increase the positioning accuracy.

  In order to achieve the above object, another clamping device according to the present invention is configured as follows, for example, as shown in FIGS. 1, 3A, and 3B.

  That is, the cylinder hole 11 provided in the housing 2 has a large-diameter hole 11a provided on the proximal end side and a small-diameter hole 11b provided on the distal end side. The piston 12 inserted into the cylinder hole 11 so as to be movable in the axial direction has a large diameter portion 13 inserted into the large diameter hole 11a and a small diameter portion 14 inserted into the small diameter hole 11b. The output rod 15 is protruded integrally from the small diameter portion 14 in the distal direction. On the outer peripheral side of the output rod 15, an engagement member 20 that can be engaged with the hole 18 of the fixed object 17 is disposed so as to be interlocked with the output rod 15. A first gap G1 formed between the first large-diameter portion 53 formed on the proximal end side of the large-diameter portion 13 and the large-diameter hole 11a is formed on the distal end side of the large-diameter portion 13. A value smaller than the second gap G2 formed between the second large diameter portion 54 and the large diameter hole 11a is set. Further, a third gap G3 formed between the first small diameter portion 58 formed on the distal end side of the small diameter portion 14 and the small diameter hole 11b is formed on the second end formed on the proximal end side of the small diameter portion 14. A value smaller than the fourth gap G4 formed between the small diameter portion 59 and the small diameter hole 11b is set.

  Here, the term “integrally” refers to the case where both the small diameter portion of the piston and the output rod are integrally formed, and the two are formed separately and fixed by screwing or the like. A case may be considered.

  The another clamping device has the following operational effects.

  When positioning the other clamping device, the first gap formed between the large diameter hole of the cylinder hole formed in the housing and the first large diameter portion of the piston and the small diameter hole of the cylinder hole and the piston The 3rd clearance gap formed between the 1st small diameter parts functions as a fitting clearance for positioning. Accordingly, the first large diameter portion is positioned in the radial direction with respect to the large diameter hole of the cylinder hole, and the first small diameter portion is positioned in the radial direction with respect to the small diameter hole of the cylinder hole. Therefore, the object to be fixed can be positioned in the radial direction with respect to the housing via the piston, the output rod integrally protruding from the small diameter portion of the piston, and the engaging member. At the time of positioning, since the length in the axial direction between the first large diameter portion and the first small diameter portion is large, the piston can be supported in the cylinder hole at a large distance. As a result, the inclination of the piston and the output rod can be reduced to increase the positioning accuracy.

  Further, since the positioning fitting gaps as the first gap and the third gap are arranged in the housing, it is possible to prevent foreign matters such as dust and chips generated during machining from being caught. For this reason, the positioning function of the clamping device can be maintained well over a long period of time. Furthermore, the present invention, unlike the above-described prior art, eliminates the need to process the fitting recess in the object to be fixed, and therefore can reduce the processing performed on the object to be fixed.

  Moreover, the clamping system according to the present invention is configured as follows, for example, as shown in FIGS.

  That is, the clamp device and the another clamp device are arranged with a predetermined interval. The pair of protrusions 70, 70 (72, 72) of the clamp device face each other so as to prevent the axis C of the clamp device from rotating around the axis C of the other clamp device. Oriented direction.

  According to the above clamping system, there is an error in the distance between the centers of the two holes of the fixed object into which the engaging member of the clamping device and the engaging member of the other clamping device are respectively inserted. In addition, the object to be fixed can be positioned in a direction in which the pair of protrusions provided on the clamp device face each other, and the pair of relief portions provided on the clamp device can absorb the error, so that the clamp device can be smoothly moved. Can work.

  Furthermore, another clamping system according to the present invention is configured as follows, for example, as shown in FIGS. 1, 2A, and 2B.

  That is, two clamping devices are arranged at a predetermined interval. The direction in which the pair of protrusions 70, 70 (72, 72) provided in one of the two clamp devices is opposed to the direction in which the pair of protrusions provided in the other clamp device is opposed. And cross.

  According to the other clamping system described above, there is an error in the distance between the centers of the two holes of the fixed object into which the engaging member of one clamping device and the engaging member of the other clamping device are respectively inserted. Even in such a case, the object to be fixed can be positioned in a direction in which the pair of protrusions provided in each clamp device face each other, and the pair of relief portions provided in each clamp device can absorb the error. It can operate smoothly.

FIG. 1 is an elevation view of a clamping device according to an embodiment of the present invention. 2A is a cross-sectional view taken along line 2A-2A in FIG. FIG. 2B is an enlarged cross-sectional view of the arrow 2B portion of FIG. 1 in plan view. 3A and 3B show another clamping device according to an embodiment of the present invention. FIG. 3A is a view similar to FIG. 2A. FIG. 3B is a view similar to FIG. 2B.

  Hereinafter, embodiments of the present invention will be described.

  First, the configuration of the clamping device will be described with reference to FIGS.

(Configuration of clamp device)
A housing 2 of a clamp device is fixed to a base plate 1 placed on a table of a machine tool. The housing 2 includes a lower housing 3 and an upper housing 4. The lower half portion of the lower housing 3 is inserted into the mounting hole 1a of the base plate 1 in a tight manner. The upper housing 4 is disposed so as to cover the lower housing 3, and is fixed to the upper surface of the base plate 1 by a plurality of fastening bolts (not shown).

  A hydraulic cylinder 10 as a drive mechanism is disposed in the lower portion of the housing 2. The hydraulic cylinder 10 includes a cylinder hole 11 formed upward from the lower surface of the lower housing 3 and a piston 12 inserted into the cylinder hole 11. The cylinder hole 11 is formed by connecting a large-diameter hole 11a and a small-diameter hole 11b upward (toward the distal end). The piston 12 has a large diameter portion 13 inserted into the large diameter hole 11a and a small diameter portion 14 inserted into the small diameter hole 11b. Here, the large diameter portion 13 and the small diameter portion 14 are integrally formed. Further, the output rod 15 protruding upward (in the distal direction) from the small diameter portion 14 is also formed integrally with the piston 12.

  In this embodiment, the output rod 15 is driven to release by being moved upward (toward the distal end) by the piston 12, and is driven to be locked by being moved downward (toward the proximal end) by the piston 12. The

  On the outer periphery of the upper portion of the output rod 15, a plurality of engaging members 20 inserted into the holes 18 of the work (fixed object) 17 and a cylindrical support member 21 are arranged vertically. A seating surface 23 for receiving the lower surface of the work 17 is formed in an annular shape on the upper surface of the upper housing 4 on the outer peripheral side of the engaging member 20. In this embodiment, four engaging members 20 are arranged at predetermined intervals in the circumferential direction. Each engagement member 20 includes a thin grip portion 26 provided at the upper portion, a trunk portion 27 provided at an intermediate height, and a lower flange 28. A plurality of saw blade-like protrusions 29 are formed on the outer periphery of the grip portion 26 in the vertical direction. Moreover, the inclined surface 30 is formed in the inner periphery of each grip part 26 so that it may approach the axial center C of piston 12 as it goes below. A wedge surface 32 that engages with the inclined surface 30 from above is formed at the top of the output rod 15. Four wedge surfaces 32 are provided corresponding to the inclined surfaces 30. In this embodiment, the wedge surface 32 and the inclined surface 30 are constituted by flat surfaces.

  An O-ring 34 made of an elastic body such as rubber is attached to the body portions 27 of the four engaging members 20. The elastic force of the O-ring 34 urges the engaging member 20 inward in the radial direction. A scraper 36 is attached to the peripheral wall of the upper hole 4 a of the upper housing 4. The elastic force of the scraper 36 urges the output rod 15 and the engagement member 20 inward in the radial direction toward the axis C of the piston 12.

  The cylindrical support member 21 includes an upper wall 40 that receives the four engaging members 20 from below, and an annular wall 41 that protrudes downward from the outer peripheral portion of the upper wall 40. The support member 21 is inserted into an accommodation hole 44 provided in the lower portion of the upper housing 4 so as to be vertically movable. Further, an advancing spring 47 made up of a plurality of disc springs is attached to the spring chamber 46 disposed below the supporting member 21, and the advancing spring 47 urges the engaging member 20 upward via the supporting member 21. ing. That is, in this embodiment, the advance spring 47 and the support member 21 constitute a support mechanism 49 that pushes up the engagement member 20 with a predetermined force.

  The large-diameter portion 13 of the piston 12 includes a first large-diameter portion 53 formed on the lower side, a second large-diameter portion 54 formed on the upper side, and the first large-diameter portion 53 and the second large-diameter portion. 54 and a large-diameter groove 55 formed therebetween. A sealing member 56 is attached to the large diameter groove 55. The small-diameter portion 14 of the piston 12 includes a first small-diameter portion 58 formed on the upper side, a second small-diameter portion 59 formed on the lower side, and a space between the first small-diameter portion 58 and the second small-diameter portion 59. And a small-diameter groove 60 formed. A sealing member 61 is attached to the small diameter groove 60.

  A pair of protrusions 70, 70 are provided on the first large-diameter portion 53 so as to face each other with the axis C therebetween. The first gap G1 formed between the protrusion 70 and the large diameter hole 11a is smaller than the second gap G2 formed between the second large diameter part 54 and the large diameter hole 11a. Is set. For example, the first gap G1 has a value of 0.02 mm to 0.03 mm, and the second gap G2 has a value of 0.1 mm to 0.2 mm.

  And a pair of relief parts 71 and 71 are formed so that it may extend in the circumferential direction between a pair of said projection parts 70 and 70 (FIG. 2B). The clearance between the escape portion 71 and the large-diameter hole 11a is, for example, a value of 0.1 mm or more and 0.2 mm or less.

  The first small diameter portion 58 is also provided with a pair of protrusions 72, 72 so as to face each other with the axis C therebetween. The third gap G3 formed between the protrusion 72 and the small diameter hole 11b is set to a value smaller than the fourth gap G4 formed between the second small diameter part 59 and the small diameter hole 11b. . For example, the third gap G3 has a value of 0.02 mm to 0.03 mm, and the fourth gap G4 has a value of 0.1 mm to 0.2 mm.

  A pair of relief portions 73 and 73 are formed between the pair of protrusions 72 and 72 so as to extend in the circumferential direction (FIG. 2A). The gap between the escape portion 73 and the small diameter hole 11b has a value of 0.1 mm or more and 0.2 mm or less, for example.

  A lock chamber 62 is formed above the large-diameter portion 13 of the piston 12, and a release chamber 63 is formed below the large-diameter portion 13. The lock chamber 62 communicates with a lock supply / exhaust port 68 through a longitudinal path 64 in the lower housing 3 and a lateral path 65 in the upper housing 4. A lower portion of a pin 66 for restraining the rotation of the piston 12 is press-fitted into the upper surface of the large diameter portion 13. The upper part of the pin 66 is inserted into the longitudinal path 64. Further, the release chamber 63 communicates with a release supply / exhaust port 67.

(Clamping device operation)
As shown in FIGS. 1 to 2B, the clamping device having the above-described configuration operates as follows.

  In the release state shown in FIG. 1, the pressure oil in the lock chamber 62 is discharged and the pressure oil is supplied to the release chamber 63. As a result, the piston 12 and the output rod 15 rise, the support member 21 and the plurality of engagement members 20 are held at the raised position by the advance spring 47, and the engagement member 20 is contracted by the elastic force of the O-ring 34. It has been switched to the diameter state. Further, the engaging member 20 and the output rod 15 are positioned coaxially with the axis C of the piston 12 by the elastic force of the scraper 36.

  In the released state, the workpiece 17 is carried into the upper side of the housing 2, the workpiece 17 is lowered by some lifting means or its own weight, and the engaging member 20 is inserted into the hole 18 of the workpiece 17. Then, the lower surface of the workpiece 17 is received by the seating surface 23 of the housing 2 (see the two-dot chain line diagram in FIG. 1).

  When the clamp device is switched from the released state of FIG. 1 to the locked state, the pressure oil in the release chamber 63 is discharged and the pressure oil is supplied to the lock supply / discharge port 68. Then, the pressurized oil is supplied to the longitudinal path 64 through the lateral path 65, and is squeezed by the gap between the inner peripheral surface of the longitudinal path 64 and the pin 66 and gradually flows into the lock chamber 62. For this reason, the impact force applied to the piston 12 by the pressure oil supplied to the lock chamber 62 is reduced, and it is possible to prevent the thin output rod 15 connected to the piston 12 from being damaged.

  Next, the piston 12 and the output rod 15 descend with respect to the support member 21 and the engagement member 20 held at the raised position by the urging force of the advance spring 47. Accordingly, the engagement member 20 is expanded in diameter by the wedge surface 32 of the output rod 15 (moved outward in the radial direction), and the engagement member 20 is engaged with the inner peripheral surface of the hole 18 of the workpiece 17. Subsequently, due to the downward force of the output rod 15, the engaging member 20 in close contact with the inner peripheral surface of the hole 18 pulls the workpiece 17 downward through the hole 18, and at the same time, the engaging member 20 and the supporting member 21 descends against the urging force of the advance spring 47. As a result, the workpiece 17 is strongly pressed against the seating surface 23.

  When the clamp device is switched from the locked state to the released state of FIG. 1, the pressure oil in the lock chamber 62 may be discharged and the pressure oil supplied to the release chamber 63. As a result, the clamping device is switched to the released state in a procedure almost opposite to the locking operation described above.

  The clamp device having the above configuration has the following advantages.

  When positioning the clamping device, the first gap G1 between the large-diameter hole 11a of the housing 2 and the projection 70 provided in the first large-diameter portion 53 of the piston 12, the small-diameter hole 11b, and the first small-diameter portion 58 The third gap G3 between the provided protrusion 72 functions as a positioning fitting gap. Accordingly, the piston 12 is positioned with respect to the cylinder hole 11 in the horizontal direction in which the pair of protrusions 70 and 70 (72, 72) face each other. For this reason, the workpiece 17 can be positioned with respect to the housing 2 via the piston 12, the output rod 15 protruding integrally from the piston 12, and the engaging member 20. The pair of relief portions 71 and 71 (73, 73) formed between the pair of protrusions 70 and 70 (72, 72) absorbs positioning errors in the direction in which the pair of relief portions face each other. To function.

  The first gap G1 formed between the large-diameter hole 11a and the protrusion 70 and the third gap G3 formed between the small-diameter hole 11b and the protrusion 72 are the housing 2 Therefore, it is possible to prevent foreign matter such as dust and chips generated during machining from being caught. For this reason, the positioning function of the clamping device can be maintained well over a long period of time. Furthermore, the present invention, unlike the prior art described above, eliminates the need to process the fitting recess in the workpiece 17, so that the processing applied to the workpiece 17 can be reduced.

  Further, the axis between the pair of protrusions 70, 70 formed on the first large diameter portion 53 of the piston 12 and the pair of protrusions 72, 72 formed on the first small diameter portion 58 of the piston 12. Since the length of the direction is large, the piston 12 can be supported in the cylinder hole 11 at a large distance. For this reason, the inclination of piston 12 and output rod 15 can be made small, and positioning accuracy can be improved more.

(Another clamping device)
3A and 3B show another clamping device in the embodiment, which are similar to FIGS. 2A and 2B, respectively.

  In the other clamping device, the configuration excluding the first large-diameter portion 53 and the first small-diameter portion 58 is the same as that of the clamping device. Therefore, the description of the same configuration is omitted, and the different configuration is illustrated in FIG. And FIG. 3B (and FIG. 1).

  The first gap G1 between the first large diameter portion 53 and the large diameter hole 11a is set to a value of, for example, 0.02 mm or more and 0.03 mm or less over the entire circumference (see FIG. 3B). The third gap G3 between the first small diameter portion 58 and the small diameter hole 11b is also set to a value of, for example, 0.02 mm or more and 0.03 mm or less over the entire circumference (see FIG. 3A).

  At the time of positioning of the other clamping device, the first gap G1 and the third gap G3 function as a positioning fitting gap. Accordingly, the first large diameter portion 53 is positioned in the radial direction with respect to the large diameter hole 11 a of the cylinder hole 11, and the first small diameter portion 58 is positioned in the radial direction with respect to the small diameter hole 11 b of the cylinder hole 11. Is done. Therefore, the workpiece 17 can be positioned in the radial direction with respect to the housing 2 via the piston 12, the output rod 15 integrally protruding from the small diameter portion 14 of the piston 12, and the engaging member 20. At the time of positioning, since the length in the vertical direction between the first large diameter portion 53 and the first small diameter portion 58 is large, the piston 12 can be supported in the cylinder hole 11 at a large distance. As a result, the inclination of the piston 12 and the output rod 15 can be reduced to increase the positioning accuracy.

  Further, the positioning fitting gaps as the first gap G1 and the third gap G3 are arranged in the housing 2, so that foreign matter such as dust and chips generated during machining is prevented from being caught. it can. For this reason, the positioning function of the clamping device can be maintained well over a long period of time. Furthermore, the present invention, unlike the prior art described above, eliminates the need to process the fitting recess in the workpiece 17, so that the processing applied to the workpiece 17 can be reduced.

(Configuration of clamping system)
The clamping device is applied to a clamping system that clamps a workpiece in cooperation with the another clamping device. In the clamping system, the clamping device and the other clamping device are arranged at a predetermined interval. The pair of protrusions 70, 70 of the clamp device are arranged in a direction substantially orthogonal to a straight line connecting the axis C of the clamp device and the axis C of the other clamp device. The pair of protrusions 72, 72 are also arranged in a direction substantially orthogonal to the straight line. Note that the pair of protrusions 70 and 70 may be disposed on both sides of a straight line connecting the axis C, and may be disposed in a direction intersecting the straight line connecting the axes. The pair of protrusions 72 and 72 may be arranged in the same direction as the pair of protrusions 70 and 70. In other words, the pair of protrusions 70, 70 (72, 72) of the clamp device is configured to prevent the shaft C of the clamp device from rotating around the axis C of the other clamp device. Opposing directions are oriented.

  The clamping system has the following advantages.

  Even if there is an error in the center-to-center distance between the two holes 18 and 18 of the workpiece 17 into which the engagement member 20 of the clamp device and the engagement member 20 of the other clamp device are respectively inserted, the clamp The workpiece 17 can be positioned in a direction in which the pair of protrusions 70, 70 (72, 72) provided in the apparatus are opposed to each other, and the pair of relief parts 71, 71 (73, 73) provided in the clamp apparatus are Since the error can be absorbed, the clamping device can be operated smoothly.

(Configuration of other clamping systems)
By arranging two of the clamping devices at a predetermined interval, the two clamping devices are applied to a clamping system that cooperates to clamp a workpiece. In the other clamping system described above, a direction in which the pair of protrusions 70 and 70 (72 and 72) provided in one of the two clamping devices arranged at a predetermined interval are opposed to each other. The direction in which the pair of protrusions provided in the other clamping device face each other is made to intersect.

  The other clamping system has the following advantages.

  Even when there is an error in the distance between the centers of the two holes 18 and 18 of the workpiece 17 into which the engaging member 20 of one clamping device and the engaging member 20 of the other clamping device are respectively inserted, The workpiece 17 can be positioned in a direction in which the pair of protrusions 70, 70 (72, 72) provided in the apparatus are opposed to each other, and the pair of relief parts 71, 71 (73, 73) provided in each clamp device are Since the error can be absorbed, the clamping device can be operated smoothly.

(Example of change)
In the clamping device shown in FIG. 1, the first gap G1 between the first large diameter portion 53 and the large diameter hole 11a is narrower than the second gap G2 between the second large diameter portion 54 and the large diameter hole 11a. In this example, the third gap between the first small diameter portion 58 and the small diameter hole 11b is narrower than the fourth gap G4 between the second small diameter portion 59 and the small diameter hole 11b.

  However, the present invention is not limited to this. That is, one of the first gap G1 and the second gap G2 is narrower than the other, and one of the third gap G3 and the fourth gap G4 is narrower than the other. Just do it. For example, the first gap G1 may be narrower than the second gap G2, and the fourth gap G4 may be narrower than the third gap G3. Further, the second gap G2 may be narrower than the first gap G1, and the third gap G3 may be narrower than the fourth gap G4. Further, the second gap G2 may be narrower than the first gap G1, and the fourth gap G4 may be narrower than the third gap G3.

  Although the example which forms the protrusion part 70 and the escape part 71 in circular arc shape was shown, this invention is not limited to this. For example, the outer peripheral surface of the first large-diameter portion 53 is formed in an elliptical shape, and both end portions on the long axis side of the outer peripheral surface are configured as protrusions 70 and 70, and the outer peripheral surface on the short axis side is a relief portion 71. , 71 may be configured. In addition, it will be apparent to those skilled in the art that the shapes of the protrusion 70 (72) and the relief 71 (73) can be variously changed.

  Moreover, while providing the pair of protrusions 70 and 70 on the large-diameter portion 13 of the piston 12 and providing the pair of protrusions 72 and 72 on the small-diameter portion 14, the present invention is not limited to this. The pair of protrusions may be provided on at least one of the large diameter portion 13 and the small diameter portion 14.

  Moreover, although the example which supports the workpiece | work 17 with a some clamping apparatus was shown, the hole for clamp apparatuses may be formed in the center of the circular shaped workpiece | work 17, and it may clamp with one clamp apparatus.

  In the embodiment shown in FIG. 1, the example of the plurality of engaging members 20 having the grip portion 26 in which the protrusion 29 is formed is shown, but the present invention is not limited to this. The engaging member 20 may be disposed on the outer peripheral side of the output rod 15 so as to be interlocked with the output rod 15 and can be engaged with the hole 18 of the fixed object 17. For example, the engagement member 20 may be an integral collet member that is arranged in an annular shape and expands / contracts in the radial direction, or moves outward in the radial direction in accordance with the movement of the output rod 15 to move the workpiece. An engagement ball that pulls down 17 may be used.

  Furthermore, in the embodiment shown in FIG. 1, an example in which the large diameter hole 11 a and the small diameter hole 11 b are formed on the same axis C is shown. However, the present invention is not limited to this. For example, the present invention can be applied to a technique in which the axis of the output rod 15 is offset from the axis of the piston 12.

  The arrangement posture of the clamp device may be reversed upside down, laterally, or obliquely with respect to the illustrated posture.

  Further, the pressure fluid used in the clamping device may be another liquid or a gas such as compressed air instead of the exemplified pressure oil.

  The fixed object to which the present invention is applied may be a work pallet or a mold instead of the illustrated work 17.

  The support mechanism 49 can use fluid pressure such as oil pressure or air pressure instead of using the urging force of an elastic body such as the illustrated spring.

  The mounting hole 1a of the base plate 1 may be omitted. In this case, the lower surface of the lower housing 3 is fixed to the upper surface of the base plate 1 via a sealing tool (not shown).

  The drive mechanism may be a pneumatic cylinder instead of the illustrated hydraulic cylinder 10. Instead of the double acting type illustrated, the fluid pressure cylinder may be driven to lock with pressure fluid and release driven with spring force, or may be locked with spring force and driven to release with pressure fluid.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

2: housing, 11: cylinder hole, 11a: large diameter hole, 11b: small diameter hole, 12: piston, 13: large diameter part, 14: small diameter part, 15: output rod, 17: work (fixed object), 18 : Hole of work 17, 20: engagement member, 53: first large diameter portion, 54: second large diameter portion, 58: first small diameter portion, 59: second small diameter portion, 70: protrusion, 71: relief Part, 72: projection part, 73: relief part, C: axial center, G1: first gap, G2: second gap, G3: third gap, G4: fourth gap.

Claims (7)

A cylinder hole (11) provided in the housing (2);
A piston (12) inserted into the cylinder hole (11) so as to be movable in the axial direction;
An output rod (15) integrally projecting from the piston (12) in the distal direction;
An engaging member (20) which is disposed on the outer peripheral side of the output rod (15) so as to be interlocked with the output rod (15) and is engageable with the hole (18) of the fixed object (17);
A pair of protrusions (70, 70) (72, 72) provided to face the outer peripheral surface of the piston (12) with an axis (C) interposed therebetween, and are fitted in the cylinder hole (11) Projecting protrusions,
A pair of relief portions (71, 71) (73, 73) formed to extend in the circumferential direction between the pair of protrusions;
A clamping device comprising:   The piston (12) has a large diameter portion (13) provided on the proximal end side and a small diameter portion (14) provided on the distal end side, and the large diameter portion (13), the small diameter portion (14), and The clamping device according to claim 1, wherein the pair of protrusions (70, 70) (72, 72) is provided on at least one of the two.   The clamping device according to claim 2, wherein the pair of protrusions (70, 70) are provided on the large diameter part (13), and the pair of protrusions (72, 72) are also provided on the small diameter part (14). . The cylinder hole (11) has a large diameter hole (11a) provided on the proximal end side and a small diameter hole (11b) provided on the distal end side,
The first large-diameter portion (53) formed on the base end side of the large-diameter portion (13) is provided with the pair of protrusions (70, 70), and the protrusion (70) and the large-diameter hole (11a). ) Between the second large diameter portion (54) formed on the distal end side of the large diameter portion (13) and the large diameter hole (11a). Set a value smaller than the formed second gap (G2),
The pair of protrusions (72, 72) is provided on the first small diameter part (58) formed on the distal end side of the small diameter part (14), and between the protrusion (72) and the small diameter hole (11b). The fourth gap formed between the second small diameter part (59) formed on the base end side of the small diameter part (14) and the small diameter hole (11b) Set to a value smaller than (G4),
The clamping device according to claim 3. A cylinder hole (11) provided in the housing (2), the cylinder hole (11) having a large-diameter hole (11a) provided on the proximal end side and a small-diameter hole (11b) provided on the distal end side; ,
A piston (12) that is inserted into the cylinder hole (11) so as to be movable in the axial direction, and is inserted into the large-diameter portion (13) and the small-diameter hole (11b) inserted into the large-diameter hole (11a). A piston (12) having a small diameter portion (14) inserted;
An output rod (15) integrally projecting from the small diameter portion (14) in the distal direction;
An engaging member (20) disposed on the outer peripheral side of the output rod (15) so as to be interlocked with the output rod (15) and engageable with the hole (18) of the fixed object (17); Prepared,
The first gap (G1) formed between the first large diameter part (53) formed on the base end side of the large diameter part (13) and the large diameter hole (11a) is defined as the large diameter part. (13) is set to a value smaller than the second gap (G2) formed between the second large diameter portion (54) formed on the tip side and the large diameter hole (11a),
A third gap (G3) formed between the first small diameter portion (58) formed on the distal end side of the small diameter portion (14) and the small diameter hole (11b) serves as a base of the small diameter portion (14). Set to a value smaller than the fourth gap (G4) formed between the second small diameter portion (59) formed on the end side and the small diameter hole (11b),
A clamping device characterized by that. A clamping system in which the clamping device according to any one of claims 1 to 4 and another clamping device according to claim 5 are arranged at a predetermined interval,
The pair of protrusions (70, 70) (72) of the clamp device so as to prevent the axis (C) of the clamp device from rotating about the axis (C) of the other clamp device. , 72) oriented in the opposite direction,
Clamping system characterized by that. A clamping system in which two clamping devices according to any one of claims 1 to 4 are arranged at a predetermined interval,
The direction in which the pair of projections (70, 70) (72, 72) provided on one of the two clamping devices is opposed to the pair of projections provided on the other clamping device. Crossed the direction to do,
Clamping system characterized by that.

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