JP2005169563A - Clamping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clamping device capable of powerfully clamping a clamped object by a clamp lever by boosting the driving force of a driving means including an air cylinder by a booster mechanism to transmit the force to the clamp lever, and simplifying the constitution of the air cylinder and considerably enhancing the durability of the booster mechanism by providing the booster mechanism outside the air cylinder. <P>SOLUTION: This clamping device 1 has an output rod 6 driven forward and backward in the axis direction by a drive mechanism 5; a pushing member 7 supported to the clamp body 2 movably in the axis direction between the clamp lever 4 and the air cylinder 20; and the booster mechanism 8 provided outside the air cylinder 20, having a plurality of steel balls 40 pushed radially outward by the advance of the output rod 6, and boosting the driving force of the output rod 6 through the steel balls 40 to transmit it to the pushing member 7 to thereby move the pushing member 7 in the direction of driving the clamp lever 4 into a clamping position. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  According to the present invention, the output rod is advanced and driven by a driving means including an air cylinder so that the driving force of the output rod is boosted and transmitted to the clamp lever by the boost mechanism, and the clamp lever is driven to the clamp position. The present invention relates to a clamping device configured as described above.

  Conventionally, a clamp body, a clamp lever movably supported by the clamp body over a clamp position and a clamp release position, a drive means including an air cylinder provided on the clamp body for driving the clamp lever, A clamp device including a booster mechanism that boosts a driving force and transmits it to a clamp lever has been put to practical use.

  In the clamp device of Patent Document 1, a cup-shaped piston is attached to an air cylinder, an output rod is inserted into an end wall and a piston on the distal end side of the air cylinder, and a proximal end portion of the output rod is a proximal end side of the air cylinder. The output rod is urged to the backward side by a backward spring. A first air chamber is formed at the distal end side of the piston of the air cylinder and a second air chamber is formed at the proximal end side. In the second air chamber, the first pressure receiving member and the first air chamber are disposed in the annular space between the piston and the output rod. Two pressure receiving members are provided facing each other in the axial direction, and a plurality of steel balls are inserted between the first and second pressure receiving members.

  The first pressure receiving member is connected to the output rod, and the second pressure receiving member is connected to the end wall on the proximal end side of the air cylinder. By supplying pressurized air to the first air chamber, the piston is driven backward by the compressed air and a compression spring attached to the first air chamber, and a plurality of taper surfaces formed on the inner peripheral surface of the piston are used. The steel ball is pushed radially inward, the output rod is driven forward and pushed out by the first and second pressure receiving members, and the clamp arm is pushed and rotated at the tip of the output rod to be clamped. Clamp.

  In the clamp device of Patent Document 2, a cup-shaped piston is attached to an air cylinder, an output rod is inserted into an end wall on the distal end side of the air cylinder, and a distal end portion of the output rod is rotatably connected to a clamp arm. ing. A first air chamber is formed on the proximal end side of the piston of the air cylinder, and a second air chamber is formed on the distal end side. In the second air chamber, the first pressure receiving portion and the second air chamber are disposed in the annular space between the piston and the output rod. Two pressure receiving portions are provided in a face-to-face manner in the axial direction, and a plurality of steel balls are inserted between the first and second pressure receiving portions.

  The first pressure receiving portion is formed on the output rod, and the second pressure receiving portion is formed on the end wall on the distal end side of the air cylinder. By supplying pressurized air to the first air chamber, the piston is driven to advance by the compressed air and a compression spring attached to the first air chamber, and a plurality of taper surfaces formed on the inner peripheral surface of the piston are used. The steel ball is pushed inward in the radial direction, the output rod is driven backward by the first and second pressure receiving portions, and the clamp arm connected to the output rod is rotated to clamp the object to be clamped. .

JP 2002-96231 A JP 2002-160135 A

  The clamping devices of Patent Documents 1 and 2 are configured to push a steel ball radially inward with a piston of an air cylinder, drive an output rod, rotate a clamp arm, and clamp an object to be clamped. Therefore, the piston of the air cylinder must be formed in a cup shape, and a tapered surface must be formed on the inner peripheral surface thereof. In addition, a plurality of steel balls and first and second pressure receiving members (first and second pressure receiving portions) must be disposed inside the piston of the air cylinder.

  In other words, the structure of the piston of the air cylinder is complicated, a plurality of steel balls and the first and second pressure receiving members are provided inside the air cylinder, and further about the compression spring and the clamping device of Patent Document 1, Since a return mechanism including a return spring for returning the output rod must be provided, the configuration of the air cylinder including these members is complicated. Therefore, the assembly of the air cylinder becomes complicated, and even when the steel ball and the first and second pressure receiving members are inspected and repaired, the air cylinder must be disassembled, which is very difficult.

  Moreover, in the clamp apparatus of patent document 1, 2, when the taper surface of the internal peripheral surface of a piston is formed in cyclic | annular form, each steel ball will be in point contact to this taper surface, and also 1st, 2nd If the pressure receiving portion is simply formed in an annular shape, each steel ball is in point contact with the first and second pressure receiving portions, and the taper surface, the first and second pressure receiving portions, and the steel ball are in contact at the contact point. Therefore, there is a problem that durability of these tapered surfaces, the first and second pressure receiving portions, and the steel balls is deteriorated.

  It is an object of the present invention to boost the driving force of a driving means including an air cylinder from a booster mechanism and transmit it to a clamp lever. The clamp lever strongly clamps an object to be clamped. The structure of the air cylinder is simplified, the assembly of the air cylinder and the booster mechanism, the inspection and repair of the booster mechanism can be performed easily, and the durability of the booster mechanism is greatly increased. It is possible to provide a clamping device.

  The clamp device according to claim 1 includes a clamp main body, a clamp lever movably supported by the clamp main body over a clamp position and a clamp release position, and an air cylinder provided in the clamp main body for driving the clamp lever. And an output rod that is driven to move back and forth in the axial direction by the driving means, and is supported by the clamp body between the clamp lever and the air cylinder so as to be movable in the axial direction. A pushing member capable of pushing the clamp lever to a clamping position; and a booster mechanism provided outside the air cylinder, wherein the steel is pushed radially outward by the advancement of the output rod. The ball has a ball, and the driving force of the output rod is boosted and transmitted to the pushing member via this steel ball, and the clamp lever is driven to the clamp position. It is characterized in that a booster mechanism for moving the pressing member to.

  In this clamp device, the output rod is driven forward and backward in the axial direction by the driving means including the air cylinder. For example, the output rod is connected so that the base end is connected to the piston of the air cylinder, is driven forward and backward integrally with the piston, is inserted into the end wall of the air cylinder on the rod advance side, and extends to the outside of the air cylinder. Established. In addition, it is preferable to provide the drive means with a biasing member that biases the output rod toward the advance side.

  When a booster mechanism is provided outside the air cylinder and the output rod is driven forward by the driving means, in the booster mechanism, for example, a plurality of steel balls are formed by a tapered portion provided at the tip of the output rod. Pushed radially outward, the driving force of the output rod is boosted and transmitted to the pusher member through this steel ball, and the pusher member moves to push the clamp lever to the clamp position. Thus, the object to be clamped is clamped.

  When moving the clamp lever from the clamp position to the clamp release position, such as when releasing the clamp object, when the output rod is driven backward by the driving means, for example, the clamp lever is moved by the biasing force of the return spring. Move to clamp release position. At this time, the pushing member may also be moved in the same direction by the urging force of the return spring, whereby the plurality of steel balls may be moved radially outward.

  According to a second aspect of the present invention, in the clamp device of the first aspect, the booster mechanism is provided at the distal end portion of the output rod so as to decrease in diameter toward the distal end side, and engages a plurality of steel balls from the radially inner side. It has a taper part. When the output rod is driven to advance by the driving means, a plurality of steel balls are pushed outward in the radial direction by the taper portion of the output rod in the boost mechanism provided outside the air cylinder, and the output is output via the steel balls. The driving force of the rod is boosted and transmitted to the pushing member.

  According to a third aspect of the present invention, there is provided the clamping device according to the second aspect, wherein the tapered portion includes a plurality of tapered grooves each having a bottom surface having an arcuate cross section in which a plurality of steel balls engage with each other in a line contact manner. To do. Since each steel ball is in line contact with the bottom surface of the corresponding tapered groove, durability of the tapered portion (a plurality of tapered grooves) and the plurality of steel balls is improved.

  A clamp device according to a fourth aspect is the invention according to any one of the first to third aspects, wherein the booster mechanism is provided in a face-to-face manner in the axial direction so that a plurality of steel balls are engaged from the radially inner side. The first receiving portion and the second receiving portion are formed, the first receiving portion is formed as a pushing member, and the second receiving portion is fixedly provided on the end wall or the end wall on the rod advance side of the air cylinder. It is characterized by being formed on a member. At least one of the first receiving portion and the second receiving portion is formed in a tapered shape that is inclined with respect to the radial direction so as to be able to receive the steel ball, whereby when the steel ball moves radially outward, the steel ball And the driving force of the output rod is boosted and transmitted to the pushing member by the first and second receiving portions.

  According to a fifth aspect of the present invention, there is provided the clamp device according to the fourth aspect, wherein the pressing member is configured in a cup shape, and the first receiving portion is formed on a base end surface of the pressing member on the air cylinder side. Is. The tip of the output rod can be inserted inside the pusher, which makes it possible to reliably advance the output rod so that the steel ball moves radially outward and the clamp lever moves to the clamp position. Is done.

  According to a sixth aspect of the present invention, in the clamp device of the fourth aspect, each of the first receiving portion and the second receiving portion has a plurality of bottom surfaces each having an arcuate cross section in which a plurality of steel balls are engaged with each other in a line contact manner. It is characterized by comprising a taper groove. Since each steel ball is in line contact with the bottom surface of the corresponding tapered groove of the first and second receiving portions, durability of the first and second receiving portions (multiple tapered grooves) and the plurality of steel balls is improved.

  According to a seventh aspect of the present invention, the clamp device according to the sixth aspect of the invention is characterized in that a rotation restricting mechanism for restricting the pushing member from rotating relative to the clamp body is provided. In a state where each steel ball is engaged with the corresponding taper groove of the first receiving portion and the second receiving portion, the rotation restricting mechanism restricts the pushing member from rotating relative to the clamp body, and the engagement. The state is securely held without being released.

  The clamp device according to claim 8 is the clamp device according to any one of claims 1 to 7, wherein the lower end portion of the clamp lever is rotatably supported by the clamp body, and the clamp lever is pushed to the central portion in the length direction of the clamp lever. An overhanging portion that protrudes toward the member side and that contacts at least a part of the pushing member is provided. At least a part of the pushing member reliably comes into contact with the overhanging portion of the clamp lever, and the clamping lever is pushed to the clamp position by the pushing member.

  According to the clamp device of claim 1, since the drive means including the clamp main body, the clamp lever, the air cylinder, the output rod, the pushing member, and the boost mechanism are provided, by driving the output rod forward by the drive means, The driving force is transmitted in the order of output rod → booster mechanism → pusher member → clamp lever. In particular, in the booster mechanism, a plurality of steel balls are pushed radially outward by the advancement of the output rod, and the output rod Since the driving force is boosted and transmitted to the pushing member, the clamp object can be strongly clamped by the clamp lever. Since the booster mechanism is provided outside the air cylinder, the configuration of the air cylinder is simplified, the air cylinder and the booster mechanism can be easily assembled, and the booster mechanism can be easily inspected and repaired. .

  According to the clamp device of claim 2, the booster mechanism is provided at the distal end portion of the output rod so as to be reduced in diameter toward the distal end side, and has a tapered portion that engages the plurality of steel balls from the radially inner side. The booster mechanism can be reliably provided outside the air cylinder, and by driving the output rod forward by the driving means, a plurality of steel balls are moved radially outward by the taper portion of the output rod in the booster mechanism. It can be surely pushed, and the driving force of the output rod can be boosted and transmitted to the pushing member via this steel ball.

  According to the clamp device of the third aspect, the taper portion is composed of a plurality of taper grooves each having a bottom surface having an arcuate cross section in which a plurality of steel balls engage with each other in a line contact manner, and therefore, the taper portion (a plurality of taper grooves). And the durability of a plurality of steel balls can be greatly improved.

  According to the clamp device of the fourth aspect, the booster mechanism has the first receiving portion and the second receiving portion that are provided facing each other in the axial direction so that the plurality of steel balls are engaged from the inside in the radial direction. The first receiving portion is formed on the pushing member, and the second receiving portion is formed on the end wall on the rod advance side of the air cylinder or the member fixedly provided on the end wall. When the steel ball moves radially outward by forming at least one of the second receiving portions into a tapered shape inclined with respect to the radial direction so that the steel ball can be received, the steel ball and the first and second By the receiving portion, the driving force of the output rod can be surely boosted and reliably transmitted to the pushing member.

  According to the clamp device of claim 5, since the pushing member is configured in a cup shape and the first receiving portion is formed on the base end surface of the pushing member on the air cylinder side, the distal end of the output rod is located inside the pushing member. The part can be inserted, and thus the output rod can be configured to be surely advanced so that the steel ball moves radially outward and the clamp lever moves to the clamp position.

  According to the clamping device of the sixth aspect, each of the first receiving portion and the second receiving portion is composed of a plurality of tapered grooves each having a cross-section arc-shaped bottom surface in which a plurality of steel balls engage with each other in a line contact manner. The durability of the first and second receiving portions (the plurality of tapered grooves) and the plurality of steel balls can be significantly increased.

  According to the clamp device of the seventh aspect, since the rotation restricting mechanism for restricting the pushing member from rotating with respect to the clamp body is provided, the first receiving portion and the second receiving portion corresponding to each steel ball are provided. In the state where the taper groove is engaged, the rotation restricting mechanism restricts the pushing member from rotating relative to the clamp body, and the engagement state is securely held, and the function of the booster mechanism is ensured. Can be maintained.

  According to the clamp device of the eighth aspect, the lower end portion of the clamp lever is rotatably supported by the clamp body, and protrudes toward the pushing member side at the central portion in the longitudinal direction of the clamp lever so that at least one of the pushing members. Since the overhanging portion with which the portion abuts is provided, the clamp lever can be reliably pushed to the clamp position and rotated by the pushing member.

A clamp device according to an embodiment of the present invention is provided for driving a clamp body, a clamp lever movably supported by the clamp body over a clamp position and a clamp release position, and a clamp lever provided in the clamp body. In particular, an output rod driven forward and backward in the axial direction by the driving means, and the clamp body and the air cylinder are movable in the axial direction between the clamp lever and the air cylinder. And a plurality of steels that are pushed outward in the radial direction by the advancement of the output rod. The ball has a ball, and the driving force of the output rod is boosted through this steel ball and transmitted to the push member, and the push member is driven in the direction to drive the clamp lever to the clamp position. And a booster mechanism for moving the.

Hereinafter, embodiments of the present invention will be described with abc in FIGS.
As shown in FIGS. 1 to 6, the clamp device 1 includes a clamp body 2, a pair of left and right guide support members 3 that guide and support the clamp body 2 movably in the front-rear direction, and a clamp position (see FIG. 5, a drive mechanism including a clamp lever 4 movably supported over a clamp release position (see FIG. 4) and an air cylinder 20 provided on the clamp body 2 for driving the clamp lever 4. 5 is provided.

  The clamp device 1 is supported by the clamp body 2 so as to be movable in the axial direction between the output rod 6, the clamp lever 4, and the air cylinder 20 that are driven back and forth in the axial direction (front-rear direction) by the drive mechanism 5. And a booster member 8 that can push the clamp lever 4 to the clamp position, and a booster mechanism 8 provided outside the air cylinder 20. (For example, three steel balls 40) A direction in which the driving force of the output rod 6 is boosted and transmitted to the pushing member 7 through the steel balls 40 to drive the clamp lever 4 to the clamp position. A booster mechanism 8 that moves the pusher member 7 (forward) and a rotation restricting mechanism 9 that restricts the pusher member 7 from turning relative to the clamp body 2 are provided.

  The clamp main body 2 has a first main body block 10 and a second main body block 11 fixed to a rear end portion of the first main body block 10, and an air cylinder 20 is fixed to the rear end portion of the second main body block 11. The clamp lever 4 is movably supported by the first main body block 10, and the pushing member 7 is movably supported by the second main body block 12.

  A pair of guided members 12 are fixedly provided on the left and right sides of the first and second main body blocks 10 and 11 and the air cylinder 20, and are long engagement grooves formed in the pair of guided members 12. The engaging portions 3a of the pair of guide support members 3 are slidably engaged with 12a. In this state, a pair of guide support members 3 are fixed to a base B for fixing a clamp object by a plurality of bolts 13, and the clamp body 2 and the air cylinder 20 are moved back and forth by the guide support members 3. The guide is supported so as to be movable in the direction.

  The first main body block 10 has a pair of left and right vertical walls 10a, and the clamp lever 4 is disposed between the vertical walls 10a. The clamp lever 4 has substantially the same vertical length and longitudinal length as the first main body block 10, and has the same lateral width as the gap between the pair of vertical walls 10 a of the first main body block 10. The clamp lever 4 has a lower end supported rotatably on the vertical wall 10a via a support shaft 14 in the left-right direction, and a clamp portion 4a protruding forward from the first main body block 10 is provided on the upper portion. A protruding portion 4b that protrudes toward the pressing member 7 side (rear side) and contacts at least a part of the pressing member 7 is provided at the central portion in the length direction.

  Here, the second body block 11 is provided with a cylindrical spring mounting member 15 on the upper side of the pushing member 7, and a return spring 16 is mounted inside the spring mounting member 15. A return rod 17 is attached to the spring mounting member 15 in a penetrating manner, and the return rod 17 is elastically urged rearward by the return spring 16. The front portion of the return rod 17 protrudes to the front side of the spring mounting member 15, and the front end portion thereof is rotatably connected to the upper end portion of the clamp lever 4, and the clamp lever 4 is moved to the clamp release position by the urging force of the return spring 16. It is possible to return.

  The drive mechanism 5 includes an air cylinder 20 and spring members 35 and 36 housed in the air cylinder 20. The air cylinder 20 has a cylinder cylinder 21, a head side end wall 22, a base end side end wall 23, and a piston 24. The cylinder cylinder 21 and the head side end wall are provided on the head side end wall 22 and the base end side end wall 23. 22, O-rings 25 and 26 that seal between the proximal end wall 23 are attached, and an annular piston seal 27 that seals between the cylinder cylinder 21 and the piston 24 is attached to the piston 24.

  The output rod 6 is movably inserted into the head side end wall 22, and is fixed using a nut 39 in a state in which a distal end portion protrudes to the front side of the air cylinder 20 and a proximal end portion is inserted into the piston 24. . A rod packing 28 that seals between the output rod 6 and the head side end wall 22 is attached to the head side end wall 22, and a seal between the piston 24 and the output rod 6 is sealed at the base end portion of the output rod 6. An O-ring 29 is attached.

  A portion surrounded by the output rod 6, the cylinder cylinder 21, the base end side end wall 23, and the piston 24 is formed in the first air working chamber 30 on the rear side of the piston 24, and on the front side of the piston 24, A portion surrounded by the cylinder cylinder 21, the head side end wall 22 and the piston 24 is formed in the second air working chamber 31. Spring members 35, 36 made of compression coil springs are mounted in the first air working chamber 30, and the pistons 24 are elastically urged forward by the spring members 35, 36 against the proximal end wall 23.

  In the air cylinder 20, air ports 32 and 33 (see FIG. 3) capable of supplying / discharging pressurized air to the first and second air working chambers 30 and 31 are formed, and these air ports 32 and 33 supply pressurized air. / It is connected to a discharge device (not shown). When pressurized air is supplied to the first air working chamber 30 in a state where the pressurized air is discharged from the second air working chamber 31, it is output together with the piston 24 by the urging force of the pressurized air and the spring members 35 and 36. The rod 6 is driven to advance.

  Further, when pressurized air is supplied to the first air working chamber 30 in a state where the pressurized air is discharged from the second air working chamber 31, the pressurized air resists the urging force of the spring members 35 and 36. Thus, the output rod 6 is driven backward together with the piston 24. The piston 24 comes into contact with the head side end wall 22 and the output rod 6 protrudes to the maximum extent (see FIG. 6), and the piston 24 comes into contact with the base end side end wall 23 to make the output rod 6 reach the maximum extent. It will be in the state which retracted (refer FIG. 4).

  The second body block 11 is formed with a through hole 11a in the front-rear direction, and the push member 7 is fitted and supported in the through hole 11a so as to be movable in the front-rear direction. This pushing member 7 has an end wall portion 7a and a cylindrical portion 7b, is formed in a cup shape whose rear side is open, and the front surface of the end wall portion 7a is in contact with the protruding portion 4b of the clamp lever 4, so that the cylindrical portion The 1st receiving part 42 which the some steel ball 40 of the booster mechanism 8 engages from a radial inside is formed in the rear-end surface of 7b.

Next, the booster mechanism 8 will be described in detail.
The booster mechanism 8 is provided on the front side of the air cylinder 20, and a plurality of (for example, three) steel balls 40 are pushed radially outward by the advancement of the output rod 6. In this mechanism, the driving force of the output rod 6 is boosted and transmitted to the pushing member 7, and the pushing member 7 is moved forward to drive the clamp lever 4 to the clamping position.

  As shown in FIGS. 4 to 10, the booster mechanism 8 is provided with a plurality of (for example, three) steel balls 40 and a plurality of steel balls provided at the distal end portion of the output rod 6 so that the diameter decreases toward the distal end side. A first receiving portion 42 and a second receiving portion 42 which are provided facing each other in the axial direction (front-rear direction) so that the plurality of steel balls 40 are engaged from the inside in the radial direction. A receiving part 42 is provided. The plurality of steel balls 40 are arranged at predetermined intervals (for example, intervals of 120 degrees) in the circumferential direction.

  The tapered portion 41 provided at the distal end portion of the output rod 6 is composed of a plurality of (for example, three) tapered grooves 41a each having a cross-section arc-shaped bottom surface with which a plurality of steel balls 40 are engaged in line contact. The plurality of taper grooves 41a are formed at predetermined intervals (for example, at intervals of 120 degrees) in the circumferential direction. Each taper groove 41a is gently inclined forward inward in the radial direction, and the moving direction of the output rod 6 ( The inclination angle θ1 with respect to the front-rear direction is formed to be a taper of about 10 degrees. As the driving force F for driving the output rod 6 forward by the driving mechanism 5, the force F1 radially outward of the plurality of steel balls 40 is F / tan θ1, and when θ1 is about 10 degrees, F1 is about F 5.7 times.

  The 1st receiving part 42 is formed in the base end surface (rear end surface) by the side of the air cylinder 20 of the cylinder part 7b of the pushing member 7, and the cross-section circular arc shape with which the some steel ball 40 engages in a line contact form, respectively. It consists of a plurality of (for example, three) tapered grooves 42a having a bottom surface. The plurality of taper grooves 42a are formed at predetermined intervals (for example, at intervals of 120 degrees) in the circumferential direction. Each taper groove 42a is inclined rearward in the radial direction, and an inclination angle θ2 with respect to the radial direction is about 35. It is formed in a taper of degree.

  The second receiving portion 43 is formed on a ring member 45 fixedly provided on the head side end wall 22 on the rod output side of the air cylinder 20. The ring member 45 includes a flange portion 45 a and a ring portion 45 b, and the flange portion 45 a is disposed so as to be sandwiched between the second main body block 11 and the head-side end wall 22. The ring portion 45b is fitted into the rear end portion of the through hole 11a of the second main body block 11, and the second receiving portion 43 is formed on the front end surface of the ring portion 45a.

  The 2nd receiving part 43 consists of a plurality (for example, 3) taper groove 43a which has the bottom of the cross-section circular arc shape where a plurality of steel balls 40 each engage in line contact. The plurality of taper grooves 43a are formed in the circumferential direction at predetermined intervals (for example, intervals of 120 degrees), and each taper groove 43a is inclined forward in the radial direction and an inclination angle θ2 with respect to the radial direction is about 35. It is formed in a taper of degree. Accordingly, the force F1 directed outward in the radial direction of the steel ball 40 is the forward force F2 of the pushing member 7 = F1 / tan θ2, and when θ2 is about 35 degrees, F2 is about 1.4 times F1.

  Thus, the booster mechanism 8 boosts the driving force F of the output rod 6 to 1 / tan θ1 / tan θ2 times (for example, about 5.7 × 1.4 = about 8 times), and moves the pushing member 7 forward. The force is converted to a force to be driven and transmitted to the pushing member 7. In particular, since both the taper grooves 42a and 43a are tapered, the driving force F of the output rod 6 can be transmitted to the pushing member 7 by boosting the driving force F by about 8 times, for example, and the steel ball 40 is directed outward in the radial direction. The amount of movement of the push member 7 forward relative to the amount of movement can be increased.

  In the rotation restricting mechanism 9, a radial direction (longitudinal) spring pin 50 is attached to the cylindrical portion 7 b of the pushing member 7 in a penetrating manner. The protruding part is movably engaged with a groove 51 in the front-rear direction formed in the second body block 11 of the clamp body 2. Accordingly, the pressing member 7 is restricted from rotating with respect to the clamp body 2 in a state in which the pressing member 7 is allowed to move back and forth.

  Here, the spring pin 55 in the front-rear direction is implanted over the flange portion 45 a of the ring member 45 and the first main body block 11, so that the ring member 45 does not rotate with respect to the clamp body 2. To be regulated.

  Incidentally, as shown in FIG. 4, the tip of the output rod 6 is positioned inside the rear end of the cylindrical portion 7 b of the pushing member 7 with the output rod 6 retracted to the air cylinder 20 as much as possible. From this state, when the output rod 6 is driven forward by the drive mechanism 5, the tip end portion of the output rod 6 enters the cylindrical portion 7b, and as shown in FIG. In the state where it protrudes to the maximum from 20, the pushing member 7 also moves slightly forward, but the tip portion of the output rod 6 is in a state of approaching the end wall portion 7a of the pushing member 7.

  Here, the spring pin 50 attached to the cylindrical portion 7b of the pushing member 7 in a penetrating manner is in a state of protruding also to the inside of the cylindrical portion 7b. A front-rear direction groove 56 is formed at a portion other than the portion where the tapered groove 41 a is formed at the distal end portion of the output rod 6, and the output rod 6 moves forward, and the distal end portion is within the cylindrical portion 7 b of the pushing member 7. As it enters, the spring pin 50 is engaged with the groove 56. Accordingly, since the output rod 6 does not interfere with the spring pin 50, the output rod 6 advances reliably, and the output rod 6 does not rotate with respect to the pushing member 7 when the spring pin 50 is engaged with the groove 56. It becomes possible to regulate.

Next, the operation and effect of the clamping device 1 will be described.
First, the required number of clamping devices 1 are mounted on a base B such as a work pallet for fixing a clamping object W such as a workpiece. In each clamping device 1, as shown in FIG. In the state of returning to the clamp release position, the clamp object W is set so that the portion to be clamped is positioned below the clamp portion 4 a of the clamp lever 4. Here, when returning the clamp lever 4 to the clamp release position, as will be described in detail later, in the drive mechanism 5, the pressurized air is supplied to the second air working chamber 31.

  When setting the clamp device 1 and the clamp object W, first, in each clamp device 1, the clamp object 2 is retracted with respect to the guide support member 3 fixed to the base B. After setting W, the clamp body 2 can be advanced, and the clamp portion 4a of the clamp lever 4 can be positioned above the portion to be clamped by the clamp object W. Note that the guide support member 3 and the clamp body 2 may be fixed so as to be able to be released by a fixing means such as a set screw.

  Then, each clamp apparatus 1 is operated as follows. First, in the drive mechanism 5, the pressurized air is discharged from the second air working chamber 31 and the pressurized air is supplied to the first air working chamber 30. Then, the output rod 6 is driven forward together with the piston 24 by the pressurized air supplied to the first air working chamber 30 and the urging force of the spring members 35 and 36. With the advancement of the output rod 6, in the booster mechanism 8, the plurality of steel balls 40 are respectively pushed radially outward by the taper portions 41 (the plurality of taper grooves 41a) at the tip portion of the output rod 6, and these steels The driving force of the output rod 6 is boosted through the ball 40 and transmitted to the pushing member 7.

  In this case, a plurality of steel balls 40 pushed outward in the radial direction, a first receiving portion 42 (a plurality of taper grooves 42a) and a second receiving portion 43 (a plurality of the steel balls 40 engaged from the inside in the radial direction). The driving force of the output rod 6 is boosted by the taper groove 43a), converted into a force for pushing the pushing member 7 forward and transmitted to the pushing member 7, and the pushing member 7 is pushed forward. If it does, it will contact with the overhang | projection part 4a protruded to the rear side of the clamp lever 4, and will push the clamp lever 4 ahead.

  That is, as shown in FIG. 5, the clamp lever 4 is rotated counterclockwise in the drawing and driven to the clamp position by the pushing member 7, and the clamped object W is clamped to the base B by the clamp portion 4 a. Is done. Note that it is preferable that the clamped object W is clamped to the base B while maintaining the state in which the pressurized air is supplied to the first air working chamber 30. However, even when pressurized air is discharged from the first air working chamber 30, the clamping object W can be clamped to the base B by the urging force of the spring members 35 and 36.

  On the other hand, when the clamp target W is released, the driving mechanism 5 discharges the pressurized air from the first air working chamber 30 and supplies the pressurized air to the second air working chamber 31. Then, with the pressurized air supplied to the second air working chamber 31, the output rod 6 together with the piston 24 is driven to retract backward against the urging force of the spring members 35 and 36. Due to the retraction of the output rod 6, the plurality of steel balls 40 can move inward in the radial direction and the pushing member 7 can move backward.

  Therefore, as shown in FIG. 4, the clamp lever 4 is rotated clockwise in the drawing and moved to the clamp release position by the return spring 16, and the movement of the clamp lever 4 causes the pushing member 7 to be The taper portion 42 (the plurality of taper grooves 42a) maintains the engaged state with the plurality of steel balls 40 and moves rearward. Thus, the clamp object W can be released from the clamp, and the clamp body 2 can be removed from the base B by retracting the clamp body 2 with respect to the guide support member 3 as necessary.

  As described above, according to the clamp apparatus 1, the clamp body 2, the clamp lever 4, the drive mechanism 5 including the air cylinder 20 and the spring members 35 and 36, the output rod 6, the pushing member 7, and the booster mechanism 8 are provided. Therefore, by driving the output rod 6 forward by the drive mechanism 5, the driving force is transmitted in the order of the output rod 6 → the booster mechanism 8 → the pushing member 7 → the clamp lever 4, and in particular, the booster mechanism 8. Then, since the plurality of steel balls 40 are pushed radially outward by the advancement of the output rod 6 and the driving force of the output rod 6 is boosted and transmitted to the pushing member 7, the clamp lever 4 can clamp the object to be clamped. W can be clamped strongly.

  Since the booster mechanism 8 is provided outside the air cylinder 20, the configuration of the air cylinder 20 is simplified, the air cylinder 20 and the booster mechanism 8 are easily assembled, and the booster can be obtained without disassembling the air cylinder 20. Inspection / mechanism of the mechanism 8 (the plurality of steel balls 40, the taper portion 41 formed on the output rod 6, the first receiving portion 42 formed on the pushing member 7, and the second receiving portion 43 formed on the ring member 45) Repair can be easily performed.

  Since the booster mechanism 8 has a tapered portion 41 that is provided at the distal end portion of the output rod 6 so as to decrease in diameter toward the distal end side and engages with the plurality of steel balls 40 from the inside in the radial direction, the booster mechanism 8 is It becomes possible to reliably provide the outside of the cylinder 20, and when the output rod 6 is driven to advance by the drive mechanism 5, in the booster mechanism 8, the plurality of steel balls 40 are radially arranged by the tapered portion 41 of the output rod 6. It can be surely pushed outward and the driving force of the output rod 6 can be boosted and transmitted to the pushing member 7 via the steel ball 40.

  The booster mechanism 8 includes a first receiving portion 42 and a second receiving portion 43 that are provided facing each other in the axial direction so that the plurality of steel balls 40 are engaged from the inside in the radial direction. The portion 42 is formed on the pushing member 7, the second receiving portion 43 is formed on the ring member 45 fixedly provided on the end wall 22 on the rod advance side of the air cylinder 20, and the first and second receiving portions 42 are formed. , 43 are formed in a tapered shape inclined with respect to the radial direction so that the steel ball 40 can be received, and when the steel ball 40 moves outward in the radial direction, the steel ball 40 and the first and second receiving portions 42 are formed. , 43 can surely boost the driving force of the output rod 6 and transmit it to the pushing member 7 reliably.

  The pushing member 7 is configured in a cup shape, and the first receiving portion 42 is formed on the base end surface of the pushing member 7 on the air cylinder 20 side, so that the distal end portion of the output rod 6 can be inserted inside the pushing member 7. Thus, the output rod 6 can be configured to be surely advanced so that the steel ball 40 moves radially outward and the clamp lever 4 moves to the clamp position.

  The tapered portion 41 provided at the distal end portion of the output rod 6 is composed of a plurality of tapered grooves 41a having a bottom surface having an arcuate cross section in which a plurality of steel balls 40 are engaged in line contact with each other. Since each of the second receiving portions 43 includes a plurality of tapered grooves 42a and 43a having a bottom surface having an arcuate cross section in which a plurality of steel balls engage with each other in a line contact manner, the plurality of steel balls 40 and the tapered portions 41 ( The durability of the plurality of tapered grooves 41a), the first receiving portion 42 (the plurality of tapered grooves 42a), and the second receiving portion 43 (the plurality of tapered grooves 43a) can be significantly increased.

  The ring member 45 in which the second receiving portion 43 is formed is prevented from rotating with respect to the clamp body 2, and the pushing member 7 in which the first receiving portion 42 is formed does not rotate with respect to the clamp body 2. Since the rotation restricting mechanism 9 for restricting is provided, each steel ball 40 is engaged with the corresponding tapered grooves 43a and 43a of the first receiving portion 42 and the second receiving portion 43 with respect to the clamp body 2. Thus, the pushing member 7 and the ring member 45 are regulated so as not to rotate, the engagement state is reliably maintained, and the function of the booster mechanism 8 can be reliably maintained.

  The lower end of the clamp lever 4 is rotatably supported by the clamp body 2, and protrudes toward the pushing member 7 (rear side) at the center in the longitudinal direction of the clamp lever 4 to at least a part of the pushing member 7. Since the overhanging portion 4b is provided, the clamp lever 4 can be reliably pushed and rotated to the clamp position by the pushing member 7.

Next, a modification in which the above embodiment is partially changed will be described.
1] In the booster mechanism 8, the number and size of the steel balls 40 can be appropriately changed. In this case, the taper portion 41 and the first and second receiving portions 42 and 43 (the number and size of the taper grooves 41a, 42a, and 43a) corresponding to the number and size of the steel balls 40 are configured.

2] The drive mechanism 5 may be configured to be able to clamp the clamping object W by generating a driving force for driving the output rod 6 to advance only by the pressurized air supplied to the first air working chamber 30. . However, when clamping the clamp target W, it is configured to be able to maintain a state in which pressurized air is supplied to the first air working chamber 30.
3] The drive mechanism 5 may be configured to be able to clamp the clamping target W by generating a driving force for driving the output rod 6 forward only by the urging force of the spring members 35 and 36.

4] The drive mechanism 5 is provided with a spring member that elastically biases the piston 24 rearward, and the piston 24 is driven backward by the biasing force of the spring member so that the clamp lever 4 can be switched to the clamp release position. May be. In this case, the supply of pressurized air to the second air working chamber 31 can be made unnecessary.

5] The tip portion of the output rod 6 is formed as a whole in a tapered portion 41 (tapered shaft portion) whose diameter decreases toward the tip side, and this tapered portion 41 engages with the plurality of steel balls 40 from the radially inner side. You may comprise as follows. Since each steel ball 40 and the taper portion 41 are in point contact, their durability is reduced, but the taper portion 41 can be easily formed on the output rod 6.

6] Similarly, the 1st receiving part 42 and the 2nd receiving part 43 are formed in the taper surface inclined with respect to radial direction entirely, The taper surface of this 1st receiving part 42 and the 2nd receiving part 43 Moreover, you may comprise so that the some steel ball 40 may engage from radial inside. Since each steel ball 40 and the first and second receiving portions 42 and 43 are in point contact with each other, their durability is lowered. The receiving part 43 can be formed easily.

7] Without forming both the first receiving portion 42 and the second receiving portion 43 in a tapered shape inclined with respect to the radial direction, one of the first receiving portion 42 and the second receiving portion 43 is set in the radial direction. It forms in the taper shape inclined with respect to it. Even in such a case, when the steel ball 40 moves radially outward, the driving force of the output rod 6 is surely boosted by the steel ball 40 and the first and second receiving portions 42 and 43, and the pushing member 7 is moved. It can be converted into a force for driving forward and can be reliably transmitted to the pushing member 7.

8] The ring member 45 may be omitted, and the second receiving portion 43 may be formed on the end wall 22 of the air cylinder 20 on the rod advance side.
9] In addition, various modifications can be added and implemented without departing from the spirit of the present invention.

It is a front view of the clamp device concerning the example of the present invention. It is a top view of a clamp device. It is a side view of a clamp device. It is a longitudinal cross-sectional view of a clamp apparatus (clamp releasing state). It is a longitudinal cross-sectional view of a clamp apparatus (clamp state). It is a longitudinal cross-sectional view of a clamp apparatus (maximum clamp drive state). It is a front view of an output rod and a steel ball. It is a VIII arrow line view of FIG. It is a rear view of a pushing member and a steel ball. FIG. 10 is a view on arrow X in FIG. 9.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Clamp apparatus 2 Clamp main body 4 Clamp lever 4b Overhang | projection part 5 Drive mechanism 6 Output rod 7 Pushing member 8 Booster mechanism 9 Rotation restriction mechanism 20 Air cylinder 40 Steel ball 41 Tapered part 41a Tapered groove 42 1st receiving part 43 2nd receiving part 42a, 43a Tapered groove 45 Ring member

Claims (8)

A clamp body, a clamp lever that is movably supported by the clamp body over a clamp position and a clamp release position, and a driving means that is provided on the clamp body and includes an air cylinder for driving the clamp lever. In the clamping device,
An output rod that is driven back and forth in the axial direction by the drive means;
A pressing member supported between the clamp lever and the air cylinder so as to be movable in the axial direction on the clamp body, and capable of pressing the clamp lever to a clamp position;
A booster mechanism provided outside the air cylinder, having a plurality of steel balls pushed outward in the radial direction by the advancement of the output rod, and driving force of the output rod through the steel balls A booster mechanism that boosts and transmits to the pusher member and moves the pusher member in a direction to drive the clamp lever to the clamp position
A clamping device comprising:   The said booster mechanism is provided in the front-end | tip part of an output rod so that it may reduce in diameter toward the front end side, and has a taper part engaged with a some steel ball from radial inside. Clamp position.   The clamping device according to claim 2, wherein the tapered portion includes a plurality of tapered grooves each having a bottom surface having a circular arc shape in which a plurality of steel balls engage with each other in a line contact manner.   The booster mechanism has a first receiving portion and a second receiving portion that are provided in a face-to-face manner in the axial direction so that a plurality of steel balls engage from the inside in the radial direction, and the first receiving portion is 4. The push member is formed, and the second receiving portion is formed on an end wall on the rod advance side of the air cylinder or a member fixedly provided on the end wall. Clamping device.   The clamp device according to claim 4, wherein the push member is configured in a cup shape, and the first receiving portion is formed on a base end surface of the push member on the air cylinder side.   5. Each of the said 1st receiving part and the 2nd receiving part consists of a some taper groove | channel which has a cross-sectional arc-shaped bottom surface where a some steel ball engages in a line contact form, respectively. Clamping device.   The clamp device according to claim 6, further comprising a rotation restricting mechanism for restricting the pressing member from rotating relative to the clamp body. The clamp lever is rotatably supported at its lower end by the clamp body, and is provided with an overhang at the center of the clamp lever in the length direction so that at least a part of the push member abuts. The clamping device according to any one of claims 1 to 7, wherein

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