JP3410212B2 - Clamping device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for clamping an object to be fixed such as a mold or a work by a balance type clamp arm.

[0002]

2. Description of the Related Art As a clamp device of this type, there is one disclosed in Japanese Patent Application Laid-Open No. 54-36680 previously proposed by the present inventor. As shown in FIG. 24, this device is configured as follows.

A clamp device 102 extending in the front-rear direction (referred to as the left-right direction in FIG. 24, hereinafter the same) is fixed to a fixed base 101 of the processing machine, and the housing 10 of the clamp device 102 is fixed.
The mold D is placed on the front side of 3. The mold D can be pressed against the upper surface of the fixed base 101 by the clamp arm 105.

A fulcrum portion 105 is provided at the rear of the clamp arm 105.
a is provided, and a force point portion 105b is provided in the middle of the clamp arm 105 in the front-rear direction. The fulcrum portion 105a is supported on the upper surface of the support block 113 so as to be vertically swingable.
The small diameter pin 122 is fitted in the eccentric position of the large diameter pin 121 fitted in the force point portion 105b, and both ends of the small diameter pin 122 are fixed in pin holes (not shown) of the housing 103. Reference symbol A is the axial center of the small diameter pin 122, and reference symbol B is the axial center of the large diameter pin 121.

The large-diameter pin 121 is attached to the upper end 11 of the lever 119.
9a is fixed and the lower end 119 of the lever 119 is fixed.
b is connected to the front end of the piston rod 150 of the double-acting hydraulic cylinder 106. A clamp working chamber 144 and an unclamp working chamber 146 are formed on the front side and the rear side of the piston 140. Reference numeral 145 is a spring for holding the clamped state.

In the unclamped state shown in the figure, pressure oil is discharged from the clamp working chamber 144 and pressure oil is supplied to the unclamp working chamber 146, whereby the clamp arm 105 is moved to the unclamp position by the return spring 155. Has been restored. Mold D by the clamp arm 105
In the case of clamping, the pressure oil is discharged from the unclamping operation chamber 146 and the pressure oil is supplied to the clamping operation chamber 144 to move the piston 140 and the piston rod 150 to the right. As a result, the large diameter pin 121 is replaced by the small diameter pin 122.
Eccentrically rotates in the counterclockwise direction about the axis A of the above, and the action point portion 105c of the clamp arm 105 is strongly rocked downward.

In the clamped state, as shown by the two-dot chain line arrow in the figure, the clamping reaction force h acts from the mold D to the action point portion 105c, and the fulcrum reaction force f from the support block 113 to the fulcrum portion 105a. In addition to acting, the operation reaction force g acts from the housing 103 via the small diameter pin 122 and the large diameter pin 121 to the force point portion 105b. This operation reaction force g is g = h + f = depending on the balance of the vertical force and the balance of the moment.
It is given as h · (m + n) / n.

[0008]

The above-mentioned conventional techniques have the following problems. At the end of the clamp operation, a strong operation reaction force g obtained by adding the value of the fulcrum reaction force f to the value of the clamp reaction force h acts on the force point portion 105b, so that the clamp arm 105 and the large diameter pin 121 are used. A large frictional force acts between the fitting surfaces between the large diameter pin 121 and the small diameter pin 122, and a large frictional force also acts between the fitting surfaces between the large diameter pin 121 and the small diameter pin 122.

In order to clamp and drive the clamp arm 105 against such a large frictional force, the hydraulic cylinder 1
It is necessary to build 06 with a large capacity. Further, as described above, since the operation reaction force g is large, the force acting on the small-diameter pin 122 is also large, and the housing 10 supports the same.
Since it is necessary to increase the thickness of the front wall portion of 3, the length of the housing 103 in the front-rear direction also increases. As described above, since the driving means such as the hydraulic cylinder 106 has a large capacity and the length of the housing 103 in the front-rear direction is large, the clamp device 102 is large and heavy. An object of the present invention is to make a clamp device small and lightweight.

[0010]

In order to achieve the above object, the present invention has a clamp device configured as follows.

(Invention of Claim 1) For example, FIG. 1 to FIG. 6 or FIG. 10 and FIG. 11 to FIG.
4, and as shown in FIGS. 18 to 20, respectively, a fulcrum portion 5a is provided at an intermediate portion in the front-rear direction of the clamp arm 5,
The clamp arm 5 is supported by the housing 3 via the fulcrum portion 5a so as to be vertically swingable, and a force point portion 5b is provided at the rear portion of the same clamp arm 5, and the eccentric transmission is made to the force point portion 5b. The first shaft 21 of the tool 18 is engaged in a transmission manner, and the second shaft 22 of the eccentric transmission tool 18 is supported by the housing 3.
The output portion 6a of the drive means 6 is configured to allow the first shaft 21 to be eccentrically rotated about the axis A of the second shaft 22 via the lever 19 so that the second shaft 2 can be driven when the clamp is driven.
The housing 3 is provided with a support wall 25a that supports the movable body 2 in the front-rear direction.

The drive means 6 may be a fluid pressure cylinder such as a pneumatic cylinder or a hydraulic cylinder, or a mechanism for advancing and retracting by screwing a male screw and a female screw. Incidentally, in the case of the hydraulic cylinder, the pressure of the working fluid can be made higher than that of the pneumatic cylinder, so that the driving means 6 thereof is further downsized.

[0013] The first axis 21 of the and the second shaft 22, when formed integrally (see FIG. 6), when formed separately (refer to FIG. 14) are considered. The lever 19 may be formed separately from the first shaft 21 (see FIG. 6) or may be formed integrally with the first shaft 21 (see FIG. 14) .

[0014] (the invention of claim 2) For example, as shown in FIG. 14 from FIG. 6, or FIG. 10 or FIG. 11, FIG. 1, in the first aspect described above, the front-rear direction to the support wall 25a The rolling element 24, which is rotatably butted, is provided on the second shaft 22. The rolling element 24 may be a cylindrical roller, a commercially available roller bearing, or the like.

[0015] (the invention of claim 3) For example, as shown in FIG. 20, or FIG. 23 from FIG. 21 from FIG. 18, in the first aspect mentioned above, can slide back and forth direction to the support wall 25a The sliding surface 76 that comes into contact with is provided on the second shaft 22.

[0016] (invention of claim 4) For example, as shown in FIG. 14 from FIG. 6, or FIG. 11 from FIG. 1, in the construction of claims 1-3 above, the front of the housing 3 A guide groove 14 extending in the front-rear direction is formed, and the fulcrum portion 5a of the clamp arm 5 is supported in the guide groove 14 so as to be movable in the front-rear direction.

(Invention of Claim 5 ) For example, as shown in FIG. 11 to FIG.
In the configuration of No. 4 , the guide groove 14 is inclined rearward and upward at a predetermined angle θ.

(Invention of Claim 6 ) For example, as shown in FIG. 11 to FIG.
In the configuration of No. 5 , it is configured as follows. One end 19a of the lever 19 is connected to the first shaft 21, and the other end 19b is supported by the output part 6a so as to be vertically swingable. Another lever 70 in the direction opposite to the direction of 19a.
The fulcrum portion 71 for amplification is provided on the protruding portion of the other lever 70, and the stopper wall 72 that receives the fulcrum portion 71 from the rear side is provided on the housing 3.

[0019] (the invention of claim 7) For example, as shown in FIG. 14 from FIG. 6, or FIG. 11 from FIG. 1, in the construction of 6 claim 1 above, those with the following configuration: Is. The housing 3 is configured to include left and right blocks 7 and 8 provided on both the left and right sides of the clamp arm 5, and upper and lower blocks 9 and 10 connecting the left and right blocks 7 and 8.

[0020]

(Invention of Claim 1) The invention of Claim 1 operates as follows, as shown in FIG. 1 (or FIGS. 11 and 12), for example. When switching the clamp arm 5 from the unclamped state of FIG. 1 (b) to the clamped state of FIG. 1 (c), the output portion 6a of the driving means 6 is moved forward.
Move forward (to the left in the figure). Then, as shown in FIG. 1C, the lever 19 is swung in the clockwise direction, and the first shaft 21 is rotated in the clockwise direction about the axis A of the second shaft 22. To be done. As a result, the force point portion 5b of the arm 5 swings upward about the fulcrum portion 5a, and the action point portion 5c clamps and swings downward about the fulcrum portion 5a.

In the clamped state, the clamp reaction force H acts from the fixed object D such as a mold to the action point portion 5c, the fulcrum reaction force F acts from the housing 3 to the fulcrum portion 5a, and the housing 3 moves to the first position. The operation reaction force G acts on the power point portion 5b via the two shafts 22 and the first shaft 21. Operation reaction force G
Is given by the equation: G = F−H = HM · N / by the balance of the vertical force and the balance of the moment. Therefore, the operation reaction force G becomes smaller than the fulcrum reaction force F by the clamp reaction force H. In addition, the operation reaction force G depends on the lever ratio of the clamp arm 5.
By making the value of (M / N) smaller than 1, the value becomes smaller than the clamp reaction force H.

Here, the present invention and the above-mentioned conventional example (see FIG. 24)
And H = h, M = m, N = n in order to compare with, the operation reaction force g of the conventional example is g = h. (M + n) / n = H. (M + N) / N = (H. M / N)
+ H: It becomes an expression. By comparing the above equations with the above equations, it can be seen that the value of the operation reaction force G of the present invention is smaller than the value of the operation reaction force g of the conventional example by the value of the clamp reaction force H.

Further, the invention of claim 1 is, for example, as shown in FIG.
As shown in (b) and FIG. 1 (c), or FIG. 11, it operates as follows. When the axis B of the first shaft 21 is eccentrically rotated toward the clamp side and the axis B is slightly moved in the forward direction (leftward in the drawing), the second shaft 22 is also moved in the forward direction. Try to. Then, the second shaft 22 is smoothly moved forward along the support wall 25a.
The frictional resistance acting between the housing 3 and the housing 3 is also small.

(Invention of Claim 2 ) The invention of Claim 2 operates as follows, for example, as shown in FIG. 1 (b) and FIG. 1 (c), or FIG. When the first shaft 21 is slightly moved forward as described above, the second shaft 22 is smoothly moved by the rolling elements 24 along the support wall 25a. Therefore, the frictional resistance acting between the second shaft 22 and the housing 3 is further reduced.

(Invention of Claim 3 ) The invention of Claim 3 operates as follows, for example, as shown in FIGS. 18 to 20, or 21 to 23. When the first shaft 21 is slightly moved forward as described above, the second shaft 22 is supported by the sliding surface 76 so as to support the wall 25.
It is smoothly moved along a. Therefore, the second shaft 2
The frictional resistance acting between 2 and the housing 3 is further reduced.

(Invention of Claim 4 ) The invention of claim 4 operates as follows, for example, as shown in FIG. 1 (or FIG. 11 and FIG. 12). In the retracted state of FIG. 1A, the clamp arm 5 is switched to the retracted position X by the output portion 6a of the driving means 6. When the fixed object D such as a mold is clamped by the arm 5, the output portion 6a of the driving means 6 is advanced to the left in the drawing.

Then, first, as shown in FIG. 1B, the arm 5 is moved leftward along the guide groove 14, and the fulcrum portion 5a of the arm 5 is moved to the front wall of the guide groove 14. It is received by and the arm 5 is switched to the advanced position Y. Next, as shown in the clamped state of FIG. 1C, the arm 5 is clamp-oscillated by the lever 19 and the eccentric transmission tool 18, and the action point portion 5
c strongly presses the mold D.

When the clamped state shown in FIG. 1 (c) is released, the output portion 6a is retracted to the right.
Then, the clamp arm 5 is moved from the clamp position Z shown in FIG. 1C to the position shown in FIG. 1C by the lever 19 and the eccentric transmission 18.
It is swung to the advance position Y of (b), and subsequently, it is retreated to the right along the guide groove 14 and switched to the retreat position X of FIG. 1 (a). In this way, by switching the clamp arm 5 from the advanced position Y to the retracted position X, the action point portion 5c of the arm 5 can be retracted from the upper surface of the fixed object D such as a mold. The fixed object D can be carried in and out in the vertical direction in the figure.

(Invention of Claim 5 ) The invention of Claim 5 operates as follows, as shown in FIGS. 11 and 12, for example. In the retracted state of FIG. 12, the clamp arm 5 is retracted in the upper right direction along the guide groove 14,
The lower surface of the action point portion 5c of the arm 5 is separated from the upper surface of the fixed object D by an unclamping height U. At the time of clamping, the output part 6a of the driving means 6 is moved leftward. Then, as shown in FIG.
Is advanced to the lower left direction along the guide groove 14 and is switched to the advanced position Y. The action point portion 5c is moved down from the retracted position X to the advanced position Y by the retracted height V. Subsequently, the arm 5 is swung in the counterclockwise direction to be switched to the clamp position (not shown). The action point portion 5c has a release height W from the advance position Y to the clamp position.
Is lowered only.

At the time of unclamping, the output portion 6a is moved rightward from the clamped state. Then, first, as shown in FIG. 11, the arm 5 is swung back to the advanced position Y, and the action point portion 5c is lifted by the release height W. Next, the arm 5 is inserted into the guide groove 14
12 is moved backward in the upper right direction, the operating point portion 5c is further raised by the retracted height V, and is switched to the retracted position X in FIG. At the retracted position X, the lower surface of the action point portion 5c is separated from the upper surface of the fixed object D by the unclamping height U.

As described above, the clamp arm 5 is clamped and unclamped with respect to the surface to be clamped of the object D to be clamped, so that the arm 5 can be switched smoothly and reliably. More specifically,
When the above-mentioned fixed object D is used for a long period of time, the clamped surface is plastically deformed into a concave shape at the portion pressed by the action point portion 5c, and the outer region of the pressed portion is different from that of another object. It may swell due to burrs or rust caused by a collision. Point of action 5c of the arm 5
Since it moves forward and backward from the diagonally upper side, it interferes with the above-mentioned bulging portion and moves smoothly.

Further, by tilting the guide groove 14, the arm 5 can be moved up and down by the retracted height V.
When the unclamping height U is set to a predetermined value, the release height W is equal to the size of the retract height V described above.
The size of becomes smaller. As a result, the swinging angle for releasing the arm 5 can be reduced, and the stroke for advancing and retracting the output portion 6a can be reduced.

(Invention of Claim 6 ) The invention of claim 6 operates as follows, as shown in FIGS. 11 and 12, for example. When unclamping the clamp arm (not shown) in the clamped state, the output portion 6a of the driving means 6 is moved rightward as described above. Then, as shown in the advanced state of FIG. 11, first, the roller 71 that is the fulcrum for amplification is received by the stopper wall 72, and then the lever 19 is swung in the clockwise direction around the roller 71. . As a result, the arm 5 is largely moved in the upper right direction along the guide groove 14 and switched to the retracted position X in FIG.

In FIG. 11, the retreat distance of the arm 5 is indicated by the symbol J (= K), the lever length of the lever 19 is indicated by the symbol R, and the lever length of another lever 70 is indicated by the symbol S. When the stroke of the output portion 6a required to switch the arm 5 from the advanced position Y in FIG. 11 to the retracted position X in FIG. 12 is L (not shown), it is given by L = J · S / (R + S). . In the above equation, the value of S / (R + S) is smaller than 1, so the stroke L is smaller than the retreat distance J.

[0035]

The present invention has the following effects because it is configured and operates as described above. (Invention of Claim 1) Since the operation reaction force that acts on the force point of the clamp arm from the housing through the eccentric transmission during the operation of the clamp becomes small, the frictional force that acts between the housing or the clamp arm and the eccentric transmission is also reduced. Get smaller. Therefore, the driving means can be made small in capacity. Moreover, since the operation reaction force is small, the force acting on the eccentric transmission device is also small, and the transmission device and the structural member supporting the transmission device can be made small.
As described above, since the drive means can be made small in capacity and the eccentric transmission can be made small, the clamp device can be made small and lightweight.

Further, even when the force input portion to the first shaft of the eccentric transmission member during the clamping operation described above minutely moved in the front-rear direction is swung shift, so along a second axis of the transmission member to the support wall By moving in the front-back direction, the above-mentioned swing deviation can be absorbed. Therefore, the frictional resistance acting between the second shaft and the housing is small, and the drive means can be made in a small capacity.

(Invention of Claim 2 ) When the clamp is driven, the second shaft of the eccentric transmission can be moved lightly in the front-rear direction along the support wall by the rolling element, so that the drive means can be made with a smaller capacity.

(Invention of Claim 3 ) When the clamp is driven, the sliding surface of the second shaft of the eccentric transmission can be moved lightly in the front-rear direction along the support wall, so that the drive means can be made with a smaller capacity.

(Invention of Claim 4 ) By moving the clamp arm in the front-rear direction along the guide groove, the action point portion of the arm can be retracted from the upper surface of the fixed object such as a mold. Therefore, it is easy to carry out and carry in the fixed object.

(Invention of Claim 5 ) Since the guide groove is inclined rearward and upward, it is possible to prevent the action point portion of the clamp arm from interfering with the surface to be clamped, and perform the clamp and unclamp movement smoothly and reliably. . Further, since the arm can be raised and lowered by the inclination of the guide groove, the release height can be set to a smaller value correspondingly, and the advancing / retreating stroke of the output portion of the driving means can be reduced. As a result, the length of the housing in the front-rear direction can be reduced to make the clamp device small.

(Invention of Claim 6 ) Since the lever for operating the eccentric transmission is provided with the amplification fulcrum portion, the forward / backward stroke of the output portion of the drive means can be further reduced. As a result, the length of the housing in the front-rear direction can be further reduced, and the clamp device can be made smaller.

(Invention of Claim 7 ) Since the housing is composed of a plurality of blocks,
Compared to the integrated type, the machining allowance during machining can be greatly reduced. Therefore, the material cost of the housing can be saved and the manufacturing cost of the clamp device can be reduced.

[0043]

Embodiment (First Embodiment) FIGS. 1 to 9 show a first embodiment of the present invention. First, the configuration of the clamp device will be described with reference to FIGS. 2 is a plan view, FIG. 3 is a side view, and FIG. 4 is a vertical side view. FIG. 5 is a sectional view taken along the line V-V in FIG. 4 described above. FIG. 6 is a sectional view taken along the line VI-VI in FIG. FIG. 7 is a sectional view taken along the line VII-VII in FIG. FIG. 8 is a sectional view taken along line VIII-VIII in FIG. 5 of the above.

A clamp device 2 extending in the front-rear direction (referred to as the left-right direction in FIGS. 2 to 4, hereinafter the same) is mounted on a fixed base 1 of the injection molding machine. The housing 3 of the clamp device 2 is fixed to the fixed base 1 by the two bolts 4, and the mold D is pressed against the upper surface of the fixed base 1 by the clamp arm 5 projecting forward from the housing 3. . The clamp arm 5 is driven by a pneumatic cylinder 6 which is a driving means.

The housing 3 includes left and right blocks (right and left in FIGS. 5 and 6; the same below), upper and lower blocks 9 and 10, and these four blocks 7 and 8.
-It is composed of a plurality of bolts 11 for fastening 9 and 10 together. The clamp arm 5 is inserted between the left and right blocks 7 and 8 so as to be movable in the front-rear direction and swingable in the vertical direction. Bolt holes 7a and 8a are vertically penetrated through the front portions of the left and right blocks 7 and 8 described above.

A fulcrum portion 5a is provided at an intermediate portion in the front-rear direction of the clamp arm 5, a force point portion 5b is provided at the rear portion of the same arm 5, and an action point portion 5c is provided at the front portion of the same arm 5. Above the fulcrum portion 5a is supported on the housing 3 moves in its own resident state in the front-rear direction by pivot pin 13 extending in the lateral direction. The clamp arm 5 is
It is possible to swing up and down on the housing 3 via this fulcrum 5a.
Supported.

More specifically, guide grooves 14 extending in the front-rear direction are formed on the inner surfaces of the left and right blocks 7 and 8, and the left and right ends of the fulcrum pin 13 are fitted into the guide grooves 14. It On the upward supporting flat surface 13a provided on the pin end portion, the receiving surface 14a of the guide groove 14 is provided.
Are faced up from above. Two sliding bearings 15 on the left and right are externally fitted to the central portion of the fulcrum pin 13 in the left-right direction, and the through holes 16 of the fulcrum portion 5a are externally fitted on the sliding bearings 15 and 15.

Further, between the front walls of the left and right blocks 7 and 8 and the respective ends of the fulcrum pin 13, urethane rubber E as elastic means is mounted. This rubber E is
It has a spherical shape and is fitted into a hole 17 formed in a recess in the front peripheral surface of the fulcrum pin 13. The power point portion 5b
Is connected to the output portion 6a of the pneumatic cylinder 6 via the eccentric transmission 18 and the lever 19, and is vertically swung by the forward / backward movement of the output portion 6a.

More specifically, the above-mentioned eccentric transmission 18
Is composed of a first shaft 21 and left and right second shafts 22 and 22 which are integrally projected from both end surfaces of the first shaft 21. The axis A of the second shaft 22 and the axis B of the first shaft 21 are eccentric. Another sliding bearing 23 is press-fitted and fixed to the roller 24 which is a rolling element, and the inner peripheral surface of the bearing 23 is rotatably fitted onto the second shaft 22. On the other hand, a support groove 25 extending in the front-rear direction is formed on each inner surface of the left and right blocks 7 and 8. The roller 24 is fitted into the support groove 25. Two needle roller bearings 27 on the left and right are externally fitted to the first shaft 21, and the through holes 28 of the power point portion 5b are externally fitted to these bearings 27, 27.

Further, the upper end portion 1 which is one end portion of the lever 19 is attached to the right portion of the first shaft 21 and the right second shaft 22.
9a is externally fitted in a detent shape. The upper end 19a is
A rocking allowance groove 29 formed by recessing in the right side of the clamp arm 5.
Inserted inside. A lower end portion 19b, which is the other end portion of the lever 19, is connected to the output portion 6a of the pneumatic cylinder 6 so as to be swingable and vertically movable. That is, another roller 32 is rotatably supported by the sliding bearing 31 on the pin 30 provided at the lower end portion 19b of the lever 19, and the roller 32 is supported by the vertical groove 33 of the output portion 6a.
Inserted in.

The cylinder portion 34 of the pneumatic cylinder 6 described above.
Is composed of front and rear end plates 35 and 36 and a cylinder tube 37, and the rear end plate 36 is pressed toward the left and right blocks 7 and 8 by four long bolts 38. The piston 40 is airtightly inserted into the cylinder tube 37. Reference numeral 41 is an O-ring, and reference numeral 42 is a plastic liner. Due to the self-lubricating action of the liner 42, the piston 40 is moved with a light force.

A clamp working chamber 44 is formed between the piston 40 and the rear end plate 36, and a clamp state holding spring 45 is mounted in the clamp working chamber 44.
An unclamping operation chamber 46 is formed between the piston 40 and the front end plate 35 described above. Reference numeral 47 and reference numeral 48
Are compressed air supply / discharge ports, respectively. Incidentally, the pressure of the compressed air is about ^{4kgf / cm 2 5kgf / cm 2} ( about 0.39M
Pa to 0.49MPa).

A piston rod 50 projecting forward from the piston 40 is airtightly inserted into the front end plate 35. Reference numeral 51 is an O-ring, and reference numeral 52 is a plastic liner. Due to the self-lubricating action of the liner 52, the piston rod 50 is moved with a light force.
The output portion 6a is provided at the front end of the piston rod 50.

The front end plate 35 and the clamp arm 5 described above.
A forward spring 55 is mounted between the lower part and the lower part. Reference numeral 56 is a front spring receiver, and reference numeral 57 is a rear spring receiver. In the lower portion of the rear wall of the swingable groove 29 of the clamp arm 5,
A retracted operated portion 59 is provided. In addition, the spring 55
The arm 5 is biased in the clockwise direction about the fulcrum pin 13 by the biasing force of. As a result, the force point portion 5b of the arm 5 presses the roller 24 downward through the first shaft 21 and the second shaft 22 in order, so that the roller 24 is always brought into contact with the support wall 25a of the support groove 25. It

Furthermore, the upper side of the clamp arm 5 is
It is covered with a cover plate 61 fixed to the upper block 9. An upper dust cover 62 is configured by the front bent portion of the cover plate 61. Also,
A lower dust cover 63 is fixed to the lower block 10. The left block 7 has a clamp state detection switch 66 and an unclamp state detection switch.
(Not shown) are provided at the front and rear. These switches are
The position of the magnet 67 fixed to the left surface of the second shaft 22 is detected.

The clamp device 2 operates as follows, mainly as shown in FIG. 1A shows a retracted state, FIG. 1B shows an advanced unclamped state, and FIG.
(c) shows the clamped state. In the retracted state of FIG. 1A, the compressed air is discharged from the clamp working chamber 44 and the compressed air is supplied to the unclamp working chamber 46. Thereby, the piston 40 and the piston rod 5
0 is moved to the rear side (right side in the figure), and the clamp arm 5 is switched to the retracted position X by the lever 19.

When the mold D is clamped by the clamp arm 5, the compressed air is discharged from the unclamping operation chamber 46 and the compressed air is supplied to the clamping operation chamber 44 so that the piston 40 and the piston rod 50 are moved to the front side. Move to (left side in the figure). With this, first,
The clamp arm 5 is moved forward by the advancing spring 55 along the guide groove 14 and the support groove 25, and then the fulcrum pin 13 moves in front of the guide groove 14 as shown in FIG. The clamp arm 5 is received by the wall and is switched to the advanced position Y.

Then, as shown in FIG. 1 (c), the lever 19 is swung in the clockwise direction to move the first shaft 2
1 is rotated clockwise about the axis A of the second shaft 22. As a result, the force point portion 5b of the clamp arm 5 is swung upward around the fulcrum pin 13, so that the action point portion 5c becomes the fulcrum pin 1 of the same.
It is clamped and swung downward around 3 as a center, and first comes into contact with the upper surface of the mold D, and then the mold D is strongly pressed. As a result, the clamp arm 5 is switched to the illustrated clamp position Z.

When the first shaft 21 rotates, its axis B
Is slightly moved to the front side (left side in the figure) and the second shaft 22 is also moved to the front side, but since the roller 24 rolls along the support groove 25, the second shaft 22 has a friction resistance. Small and lightly moved. Also, at the beginning of the clamp operation,
At the same time that the above-mentioned action point portion 5c starts to contact the mold D,
Since an operation reaction force starts to be applied from the receiving surface 14a of the guide groove 14 to the supporting flat surface 13a of the fulcrum pin 13, the fulcrum pin 13 is moved forward by the frictional force acting between the both surfaces 14a and 13a. Movement to the left) is prevented.

However, at the end of the above clamp drive,
As shown in FIG. 1 (c) above, from the mold D to the action point portion 5c
Since a large clamping reaction force H acts on the fulcrum pin 13 and a larger fulcrum reaction force F acts on the fulcrum portion 5a from the fulcrum pin 13, the clamp arm 5 is elastically deformed to strongly move the fulcrum pin 13 to the front side. I will try to let you. Then, the rubber E is compressed and deformed to allow the fulcrum pin 13 to move to the front side, so that no abnormal force is applied to the fulcrum pin 13 and the front wall of the guide groove 14.

In the clamped state, the power point portion 5b passes from the housing 3 through the second shaft 22 and the first shaft 21.
The operation reaction force G acting on G depends on the balance of the vertical force and the balance of the moment, and G = F−H = HM · M /
Given as N. Therefore, the operation reaction force G is smaller than the fulcrum reaction force F by the clamp reaction force H. In addition, the operation reaction force G is set to the clamp reaction force H by reducing the value of the lever ratio (M / N) of the clamp arm 5 to less than 1.
Will be smaller than.

In the clamped state, the clamp arm 5 is firmly held at the clamped position Z by the elastic force of the clamped state holding spring 45. Incidentally, in the device of this embodiment, the clamp reaction force H is about 1.
Even when an external force of 3 to 2 times acts on the mold D, it is possible to prevent the clamped state of the arm 5 from being released. Further, even when the pressure in the clamp working chamber 44 disappears due to leakage of the compressed air from the supply pipe, the same as the above-mentioned spring 45 causes about 20% to 40% of the clamp reaction force H due to the action of the spring 45. The clamp holding force can be secured.

When the clamped state shown in FIG. 1C is released, compressed air is discharged from the clamp working chamber 44 and compressed air is supplied to the unclamp working chamber 46.
The piston 40 and the piston rod 50 are moved to the rear side (right side in the figure). Then, the swing of the lever 19 causes the first shaft 21 to rotate in the counterclockwise direction about the axis A of the second shaft 22 to release the clamping operation force, and then, as shown in FIG. As shown, the advance spring 5
5 swings the clamp arm 5 to the advanced position Y. Subsequently, as shown in FIG. 4, the rear surface of the lever 19 (the right surface in the drawing) is engaged with the retracted operated portion 59 provided at the rear portion of the clamp arm 5, and the clamp arm 5 is operated. 5 is switched to the retracted position X in FIG. 1 (a).

The above embodiment has the following advantages. As described above, since the operation reaction force is given as G = H · M / N, the operation reaction force G is made smaller than the clamp reaction force H by making the value of M / N smaller than 1. It is possible to make it smaller. Therefore, the force acting on the force application portion 5b at the end of the clamp operation becomes small, and the frictional force acting between the eccentric transmission 18 and the housing 3 and the clamp arm 5 also becomes small. Also, since the swing deviation of the force application portion 5b at the final stage of the clamp operation can be absorbed by the rolling of the roller 24 fitted onto the second shaft 22 of the transmission 18, the second shaft 22 and the housing 3 can be separated from each other. The frictional resistance that acts between them is also small. Further, the needle roller bearing 27 is provided between the force point portion 5b of the clamp arm 5 and the first shaft 21, and the sliding bearing 15 is also provided between the clamp arm 5 and the fulcrum pin 13 as described above. The friction resistance of is further reduced. Therefore, the pneumatic cylinder 6 can be manufactured with a small capacity.

Moreover, since the operation reaction force G is small as described above, the force acting on the eccentric transmission 18 is also small, and the eccentric transmission 18 and the structural member supporting it can be made small. As described above, since the pneumatic cylinder 6 can be made small in capacity and the eccentric transmission 18 and the like can be made small, the clamp device 2 can be made small and lightweight.

Further, at the end of the same clamp operation, the displacement of the fulcrum portion 5c due to the elastic deformation of the clamp arm 5 is absorbed by the rubber E which is an elastic means, so that the thickness of the front wall of the housing 3 is reduced. Fulcrum pin 1
3 can be provided in the front portion of the housing 3. As a result, the length of the housing 3 in the front-rear direction is shortened, and the clamp device 2 can be made lightweight and small.
Since the elastic means is made of rubber, it can be made compact, and since it is made of urethane, it has high durability.

The first shaft 21 and the second shaft 21 of the eccentric transmission 18 described above.
Since the upper end portion 19a of the lever 19 is fitted onto the shaft 22 in a non-rotating manner, the structure for fixing the lever 19 to the first shaft 21 is simple. Furthermore, the clamp arm 5
Since the clamp arm 5 can be switched from the advanced position Y to the retracted position X by bringing the lever 19 into contact with the retracted operated portion 59 provided in the above, it is necessary to provide a dedicated mechanism for retracting the clamp arm 5. Disappears,
The clamp device has a small number of parts, can be made with a simple structure, and has few failures. Further, since the housing 3 is composed of the plurality of blocks 7, 8, 9 and 10, the machining cost during machining is small and the material cost is low.

FIG. 9 shows a modification of the rubber E and is a view corresponding to FIG. In this case, the rubber E is formed in a cylindrical shape.

The elastic means in the above-described first embodiment and modification may be mounted on the housing 3 instead of being mounted on the fulcrum pin 13. Further, the rubber E may be another type of rubber instead of urethane rubber. further,
Instead of the rubber E, a spring such as a compression coil spring may be used as the elastic means.

Incidentally, the needle roller bearing 27
Can be replaced by sliding bearings. The sliding bearings 15, 23, 31 can be replaced by needle roller bearings. Also, the sliding bearing is
Although it may be composed of a single material such as phosphor bronze or white metal, it may be composed of a composite of a self-lubricating plastic on a metal base (so-called dry metal),
It is preferable for making maintenance free.

FIG. 10, FIG. 11 to FIG. 17, and FIG. 18 to FIG. 23 show different embodiments, respectively. In these other embodiments, members having the same configurations as those of the first embodiment will be described by attaching the same reference symbols in principle.

(Second Embodiment) FIG. 10 shows a second embodiment and corresponds to FIG. 4 described above. The clamp device of the second embodiment differs from the device of the first embodiment described above in the following points. Fulcrum pin 13
Both ends of are fitted into pin holes (not shown) provided in the housing 3 and are supported immovably in the front-rear direction. Therefore, the clamp arm 5 does not move forward and backward (left and right in the drawing) but swings at the position shown.

[0073] The above-mentioned pivot pin 13 and the pin hole
The elastic means may be provided between the elastic means (not shown). In this case, a supporting plane is provided on the fulcrum pin 13 in an upward direction, and a receiving surface facing the supporting plane is provided in the pin hole .

(Third Embodiment) FIGS. 11 to 17 show a third embodiment. First, the difference of the clamp device of the third embodiment from the device of the first embodiment will be described with reference to FIGS. 11 to 14. FIG. 11 is a vertical sectional side view of the clamp device in the advanced state, and FIG.
FIG. 13 is a vertical sectional side view of the clamp device in a retracted state, FIG. 13 is a sectional view taken along line XIII-XIII in FIG. 11, and FIG. 14 is a sectional view taken along line XIV-XIV in FIG. .

The guide groove 14 is inclined rearward and upward at a predetermined angle θ. This angle θ is preferably set in the range of about 3 to 10 degrees, and in this embodiment, it is set to about 5 degrees. The eccentric transmission 18 has a large diameter first
The shaft 21 and the small-diameter second shaft 22 are separately configured,
The first shaft 21 is fitted onto the second shaft 22. The first shaft 21 and the lever 19 are integrally formed.

Another lever 70 is provided so as to project downward from the lower end portion 19b of the lever 19. A roller 71, which is a fulcrum for amplification, is provided with a pin 73 on the protruding portion of the other lever 70.
Supported by. The roller 71 can be received from the rear side by a stopper wall 72 provided on the housing 3. The bearing 27 mounted between the through hole 28 of the force point portion 5b of the clamp arm 5 and the first shaft 21 and the other bearings 15, 23, 31, etc. are all configured by sliding bearings. The rear spring receiver 57 for the forward spring 55 is formed in a cylindrical shape, and the guide bolt 74 of the front spring receiver 56 is inserted into the cylindrical hole. Since the bolt 55 can temporarily tighten the spring 55 between the front and rear spring receivers 56 and 57, the work of mounting the spring 55 on the housing 3 is easy.

This clamp device operates as follows.
In the retracted state of FIG. 12, the piston 40 of the pneumatic cylinder 6
Is driven to the right, and the lever 19 moves the clamp arm 5 along the guide groove 14 in the upper right direction. At the retracted position X of the clamp arm 5, an unclamp height U is provided between the clamped surface of the upper surface of the mold D and the lower surface of the action point portion 5c.

At the time of clamping, the piston 40 is driven leftward. Then, first, as shown in FIG. 11, the clamp arm 5 is moved in the lower left direction along the guide groove 14 by the advancing spring 55, and the fulcrum pin 13 is received by the front wall of the guide groove 14. The action point portion 5c of the arm 5 is lowered by the retracted height V from the retracted position X to the advanced position Y. Then, the lever 1
Since 9 is swung in the clockwise direction around the eccentric transmission 18, the first shaft 21 is rotated in the clockwise direction around the axis A of the second shaft 22, and the force point portion 5b is the fulcrum pin. It is swung upward about 13 as a center. As a result, the action point portion 5c is swung downward around the fulcrum pin 13 to strongly press the die D. The point of action 5c is
The release height W is lowered from the advance position Y to the clamp position.

During unclamping, the piston 40 is driven rightward in the clamped state. Then, the lever 19 is swung in the counterclockwise direction around the transmission tool 18, and as shown in FIG.
c is swung upward by the forward spring 55. At the advanced position Y, the action point portion 5c is separated from the mold D by the release height W, and the amplification roller 71 is received by the stopper wall 72.

Therefore, when the piston 40 is driven further to the right, the lever 19 is swung in the clockwise direction around the roller 71. This allows
The arm 5 is moved in the upper right direction along the guide groove 14 and switched to the retracted position X in FIG. In this case, on the right side of the piston 40, the reverse stroke T
Is left. In FIG. 11, symbols J and K indicate the retracted distance of the arm 5, symbol P indicates the retractable clearance of the lower end portion 19b of the lever 19, and symbol Q indicates the piston 4 respectively.
This shows a reverse allowable stroke of zero. Also, the symbol R
Indicates the lever length of the lever 19 and the symbol S indicates the lever length of the other lever 70.

A piston 40 required to switch the arm 5 from the advanced position Y shown in FIG. 11 to the retracted position X shown in FIG.
Let L (not shown) be the stroke for advancing / retreating, and L = (reverse allowable stroke Q-reverse allowance stroke T) = J · S
/ (R + S) The value of S / (R + S) above is 1
Therefore, the value of the stroke L is smaller than the retreat distance J of the arm 5. Therefore, the housing 3
The length in the front-back direction becomes shorter. The above S / (R +
The value of S) is preferably set in the range of 0.33 to 0.5 and is set to about 0.4 in this embodiment.

By inclining the guide groove 14, the arm 5 can be moved up and down by the retreat height V. Therefore, when the unclamping height U is set to a predetermined value, the arm 5 is released by the retreat height V. The height W can be reduced. Therefore, the swinging angle of the clamp arm 5 for release can be reduced, and the release stroke of the piston 40 can be reduced. As a result, the length of the housing 3 in the front-rear direction can be reduced to make the clamp device small.

Further, since the guide groove 14 is inclined rearward and upward, the component force in the horizontal direction acting on the front wall of the groove 14 from the fulcrum pin 13 at the time of clamping can be small.
Therefore, the thickness of the front wall of the guide groove 14 can be reduced to make the housing 3 small. Further, by providing the amplifying roller 71, the advance / retreat stroke L of the piston 40 is reduced, and the swing distance of the lower end portion 19b of the lever 19 is shortened, so that the retractable clearance P of the lower end portion 19b is also provided. It can be small. As a result, the length of the housing 3 in the left-right direction can be reduced, and the clamp device 2 can be made smaller. The amplification fulcrum portion provided on the other lever 70 may be configured by a sliding member instead of the roller 71.

Next, an example of the test results of the clamp device 2 of the above-mentioned third embodiment will be described with reference to FIGS. FIG. 15 is a schematic diagram of the test apparatus. FIG. 16 shows test data. FIG. 17 is a view showing the operation of the clamp state holding spring provided in the clamp device. Note that the length, width, and height of the clamp device 2 are approximately 290 mm.
And 140mm and 150mm.

As shown in FIG. 15, the clamp device 2 is fixed to the upper surface of the table 80, and compressed air from the air pressure source 81 can be supplied to the clamp working chamber 44 of the clamp device 2. Reference numeral 82 is an air pressure gauge. Pneumatic cylinder 6
The piston rod 50 of is connected to a dial gauge 84 via a link 83. An intermediate pin 85 and a load cell 86 are sequentially provided on the lower side of the object D to be pressed downward by the clamp arm 5, and the load cell 86 can be pushed up by the hydraulic piston 87. Reference numeral 88 is a load indicator, and reference numeral 89 is a hydraulic source such as a hand pump.

The clamp force C of the clamp arm 5 is measured as follows. The pressure oil is discharged from the hydraulic working chamber 90 below the hydraulic piston 87, and the pressure in the clamp working chamber 44 is increased, and the load display 88 indicates the clamping force C for each predetermined air pressure. taking measurement. The measurement data is as shown in FIG. When the air pressure is zero, the clamp state holding spring 4
The clamping force C is given by 5.

Clamp release force C'when the clamp arm 5 in the clamped state is released by external force.
Is measured as follows. In each clamped state for each air pressure described above, the pressure in the hydraulic working chamber 90 is increased to press the load cell 86 upward. In a state where the arm 5 is held at the illustrated clamp position Z,
Although the piston rod 50 is held at the position shown in the drawing, when the arm 5 starts moving to the unclamp side, the piston 50 starts moving to the right. Check this with the dial gauge 84, and load indicator 88 at that time
The value of is read and the value is used as the clamp release force C '. The measurement data of the unclamping force C ′ is shown in FIG.
It is as shown in 6.

From the above data, the following can be understood. The clamping release force C ′ is required to have a large value of about 1.3 to 1.7 times the clamping force C. Therefore, the clamp arm 5 being clamped is less likely to be released, and the object D to be fixed can be strongly held. Further, even when the air pressure in the clamp working chamber 44 is lost due to breakage of the air pipe or the like, the fixed object D can be strongly held by the action of the clamp state holding spring 45.

The action of the clamp state holding spring 45 is as follows.
This will be described with reference to FIG. 17 with reference to FIGS. 11 and 12 above. The clamp arm 5 is in the retracted position X in FIG.
When driven to, the free length α spring 45 is compressed until its spring length is β ₀ . Reference numeral β ₁ is an extension / retraction elastic region during the movement of the arm 5 between the retracted position X in FIG. 12 and the advanced position Y in FIG. 11. Reference numeral β ₂ is an extension / contraction area for clamping while the arm 5 is swung between the advanced position Y and the clamp position in FIG. 11. Reference numeral β ₃ indicates the initial set compression amount. Reference numeral γ indicates the biasing force of the spring 45.

As shown in the comparison between the upper diagram and the lower diagram in FIG. 17, when the free length α of the spring 45 is constant,
By making the forward / backward expansion / contraction area β ₁ small,
Since the initial setting compression amount β ₃ can be increased, the biasing force γ in the clamping expansion / contraction region β ₂ increases. Therefore, as described above, when the advancing / retreating stroke of the piston 40 is reduced by the action of the amplifying roller 71, the spring 4
The biasing force of 5 becomes large, and the object D to be fixed can be strongly and reliably held.

18 to 23 show a fourth embodiment. FIG. 18 is a partial view corresponding to FIG. 11 described above. 19 is a cross-sectional view taken along the line XIX-XIX in FIG. 18 described above. 20 is a sectional view taken along the line XX-XX in FIG. 19 described above. The fourth embodiment is a modification of the third embodiment (see FIGS. 11 to 14) as follows. Sliding surfaces 76 are formed on the lower surfaces of both ends of the second shaft 22, and the sliding surfaces 76 slidably contact the supporting walls 25a of the supporting grooves 25 in the front-rear direction. A lubricant is interposed between the sliding surface 76 and the support wall 25a. The sliding bearing 77 is also mounted between the first shaft 21 and the second shaft 22.

As described above, the force application portion 5b of the clamp arm 5 is biased in the clockwise direction by the advance spring (not shown here). As a result, the sliding surface 76 is pressed against the support wall 25a. Therefore,
The support groove 25 may be formed as shown in the two-dot chain line in FIG.

21 to 23 respectively show the second shaft 2
It is a figure which shows the modification of the support structure of 2 and is equivalent to the above-mentioned FIG. In the first modification of FIG. 21, the upper wall of the support groove 25 is omitted. The sliding surface 76 of the second shaft 22
Is pressed against the support wall 25a by the urging force of the advancing spring, as in the fourth embodiment. In the second modified example of FIG. 22, a circular guide member 78 is rotatably supported on the end portion of the second shaft 22, and the sliding surface 7 is supported by the guide member 78.
6 is formed. In the third modification of FIG. 23, the second shaft 2
A quadrangular guide member 79 is rotatably supported at the end of 2 and the sliding surface 76 is formed on the guide member 79.

Each of the above embodiments can be modified as follows. The housing 3 includes a plurality of blocks 7/8.
It is also possible to integrally form any two or three or all of these blocks instead of the configuration of 9 and 10.

Instead of fitting the first shaft 21 of the eccentric transmission 18 into the through hole 28 formed in the force point portion 5b of the clamp arm 5, an arc-shaped groove is formed in the force point portion 5b.
The first shaft 21 may be engaged with the groove from below. The pneumatic cylinder 6 as the driving means may be one in which the clamp state holding spring 45 is omitted, and may be configured as a single acting spring returning type instead of a double acting type.

Further, the above-mentioned drive means may use other types of compressed gas in place of the pneumatic cylinder, and a hydraulic cylinder or the like may be used in place of these gas pressure cylinders. . When compressed air is used as the pressure fluid, the cost of the pressure fluid supply / discharge device and piping can be significantly reduced, and the atmosphere can be prevented from being contaminated by a liquid such as oil. Further, the drive means of the above may be a mechanism that is advanced and retracted by the engagement of the male screw and the female screw.

[Brief description of drawings]

1A and 1B are schematic views of a clamp device according to a first embodiment of the present invention, in which FIG. 1A shows a retracted state, FIG. 1B shows an advanced state, and FIG. 1C shows a clamp. It shows the state.

FIG. 2 is a plan view of the clamp device.

FIG. 3 is a side view of the same clamp device.

FIG. 4 is a vertical sectional side view of the same clamping device.

5 is a sectional view taken along line VV in FIG. 4 described above.

FIG. 6 is a sectional view taken along line VI-VI in FIG. 4 of the above.

7 is a sectional view taken along the line VII-VII in FIG. 5 described above.

8 is a sectional view taken along the line VIII-VIII in FIG. 5 of the above.

FIG. 9 is a view showing a modified example of the elastic means provided in the clamp device and corresponding to FIG. 7 described above.

FIG. 10 shows a clamp device according to a second embodiment of the present invention,
FIG. 5 is a diagram corresponding to FIG. 4 described above.

FIG. 11 shows a clamp device according to a third embodiment of the present invention,
FIG. 5 is a diagram corresponding to FIG. 4 above.

FIG. 12 is a view showing the retracted state of the clamp device and corresponding to FIG. 1 (a).

13 is a sectional view taken along line XIII-XIII in FIG. 11 described above.

FIG. 14 is a sectional view taken along the line XIV-XIV in FIG.

FIG. 15 is a schematic view of a test device for the clamp device.

FIG. 16 is test data of the clamp device.

FIG. 17 is a view showing an operation of a clamp state holding spring provided in the clamp device.

FIG. 18 shows a clamp device according to a fourth embodiment of the present invention,
FIG. 12 is a partial view corresponding to FIG. 11 described above.

19 is a cross-sectional view taken along the line XIX-XIX in FIG. 18 described above.

20 is a sectional view taken along the line XX-XX in FIG. 19 and showing a support structure for the eccentric transmission.

FIG. 21 is a diagram showing a first modification of the support structure.

FIG. 22 is a view showing a second modified example of the support structure of the above.

FIG. 23 is a view showing a third modified example of the above support structure.

FIG. 24 is a view showing a conventional example and corresponding to FIG. 1 described above.

[Explanation of symbols]

3 ... housing, 5 ... clamp arm, 5a ... fulcrum part,
5b ... power point part, 5c ... action point part, 6 ... drive means (pneumatic cylinder), 6a ... output part, 7 ... left block, 8 ... right block, 9 ... upper block, 10 ... lower block, 18 ... eccentric transmission Tool, 19 ... Lever, 19a ... One end (upper end), 19b ... Other end
(Lower end portion), 21 ... First shaft, 22 ... Second shaft, 24 ... Rolling element (roller), 25 ... Support groove, 25a ... Support wall, 70 ... Another lever, 71
... Amplification fulcrum part (roller), 72 ... Stopper wall, 76 ... Sliding surface, A ... Shaft center of second shaft 22, B ... Shaft center of first shaft 21, θ ... Predetermined angle.

Claims (7)

(57) [Claims] 1. A fulcrum portion (5a) is provided at an intermediate portion of the clamp arm (5) in the front-rear direction, and the clamp arm (5) is lifted up.
It is vertically swingably supported on the housing (3) through the fulcrum part (5a) described above, and the force point part is provided on the rear part of the clamp arm (5).
(5b) is provided, and the first shaft (21) of the eccentric transmission (18) is transmitably engaged with the force point portion (5b), and the second shaft (22) of the eccentric transmission (18) is connected. Drive means supported by the housing (3)
By the output part (6a) of (6), the first shaft (21) is eccentrically rotatable about the shaft center (A) of the second shaft (22) via the lever (19), A clamp device, characterized in that a support wall (25a) that supports the second shaft (22) so as to be movable in the front-rear direction when the clamp is driven is provided in the housing (3). 2. The clamp device according to claim 1 , wherein a rolling element (24) that comes into rolling contact with the support wall (25a) in the front-rear direction is provided on the second shaft (22). A clamping device characterized in that it is configured. 3. The clamp device according to claim 1 , wherein a sliding surface (76) that slidably contacts the support wall (25a) in the front-rear direction is provided on the second shaft (22). A clamp device characterized by being configured as follows. 4. A clamping device according to any one of claims 1 to 3, the guide groove longitudinal extending direction to the front of the housing (3)
(14) is formed in the guide groove (14).
A clamping device, characterized in that the fulcrum portion (5a) of (5) is movably supported in the front-rear direction. 5. The clamping device according to claim 4 , wherein the guide groove (14) is inclined backward and upward at a predetermined angle (θ). 6. The clamp device according to claim 5 , wherein one end (19a) of the lever (19) is connected to the first shaft (21) and the other end (19b) is connected to the output part. (6a) is swingably supported, and the lever (19) is moved in the opposite direction from the other end (19b) of the lever (19) to the other end (19a).
(70) is projectingly provided, and an amplification fulcrum part (71) is provided at the projecting part of the other lever (70). A clamp device characterized in that it is provided and configured in 3). 7. A clamping device according to any one of claims 1 to 6, wherein the housing (3) is, the right and left provided on the left and right sides of the clamp arm (5) blocks (7)
A clamping device comprising: (8) and upper and lower blocks (9), (10) connecting these left and right blocks (7), (8).