JPH0353773Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a clamp device for fixing a press mold etc. that is attached to the bed of a press machine.

[Conventional technology]

In a press machine, when fixing a lower mold of a press die or a lower frame of a die set on the bed of the press machine, a clamping device is known that uses a manually rotated cam or a clamp claw operated by a hydraulic cylinder to fix the lower die of the press mold or the lower frame of the die set on the bed of the press machine.

This known clamp device uses a hydraulic cylinder to drive a clamp pawl that swings about a horizontal axis, and the clamp pawl cannot be moved back and forth. Therefore, the tip of the clamp claw always protrudes from the front end of the main body of the clamp device.

Therefore, it is necessary to loosen the clamp claw, insert the lower ridge of the mold or die set between the substrate and the lower part of the clamp claw, and then operate the hydraulic cylinder to press the tip of the clamp claw against the ridge. To remove it, do the opposite.

[Problem that the invention attempts to solve]

When attaching a mold or die set to the conventional clamping device as described above, it is necessary to insert the protrusion of the mold into the narrow gap between the substrate and the clamp claw, which can be difficult if the mold or die set is heavy. It will be a lot of work.

As a clamping device that solves this problem, there is a device in which a clamp claw moves back and forth, as disclosed in Japanese Utility Model Application Publication No. 59-44628.

In the case of a hydraulic clamping device where the clamping claw moves back and forth, the clamping claw is initially retracted, so when placing a mold etc. on the board, the clamping claw does not get in the way, which is an advantage. A large hydraulic cylinder is provided at the rear of the main body of the press, so when this is mounted on the base of the press, the hydraulic cylinder protrudes from both sides of the base and becomes a hindrance. There are also other problems, such as the need for a hydraulic circuit for the clamp claws.

[Means for solving problems]

In order to solve the above problems, this invention provides a guide hole in the front and back direction in the main body fixed on the board, fits a clamp claw that can move forward and backward and swing freely into this guide hole, and also pulls this clamp claw. A spring acting in the closing direction and a spring pushing up the front part of the clamp claw are provided, and a rotatable cam shaft is installed in the cam hole provided in the main body so as to be orthogonal to the guide hole, This camshaft is provided with a circular cam consisting of a circumferential portion concentric with the camshaft and a recessed portion in which a part of the circumference is cut out in a straight line, and equiangular spiral cams are provided on both sides of the circular cam. A notch is provided toward the front from the center of the rear end of the clamp claw, and the lower end of the lever, whose upper end is swingably connected to the front of the notch, is engaged with the engagement hole provided at the bottom of the guide hole. Then, the lever is positioned in front of the occluded cam, and the rear lower surface of the clamp pawl located on both sides of the notch of the clamp pawl is brought into contact with the upper side of both the equiangular spiral cams, and the lever is placed in front of the notched cam. In the retreat position, the occluded circular cam and the equiangular helical cam were positioned so that the linear part of the occluded circular cam faced the lever and the shortest radius part of both the equiangular helical cams was on the upper side. It is something.

[Effect]

Since this device has the above-mentioned configuration, when the camshaft is in the non-operating position, the clamp pawl is also retracted by the action of the spring, and its tip does not protrude from the front surface of the main body.

When the camshaft is rotated from this state, the occluded cam provided on the camshaft first pushes the lever and advances the clamp pawl connected to it, causing its tip to protrude from the main body.

When the camshaft is then further rotated, the equiangular helical cam pushes up the rear part of the clamp claw, so the clamp claw tilts forward and downward around the fulcrum, and the tip of the clamp claw is crimped onto the ridge of the mold, etc. Then press it onto the board and fix it.

〔Example〕

In the figure, reference numeral 1 denotes a substrate such as the bed of a press machine, and a main body 2 is fixed onto this substrate 1 by means such as bolting. This main body 2 is provided with a guide hole 3 that longitudinally traverses the main body in the front-rear direction.

The guide hole 3 is a square hole as shown in FIGS. 2 and 4, and a clamp claw 5 with a square cross section is inserted into this hole 3.
Put on. Reference numeral 6 denotes a fulcrum member, which is in the shape of a broken sphere, and its flat part is slidably in contact with the upper surface of the guide hole 3, and the spherical part is in the spherical recess 7 on the upper surface of the front side of the clamp claw 5. It is worshiped.

A pair of left and right recesses 8 of a predetermined depth are formed from the lower surface of the clamp claw 5 slightly in front of the spherical recess 7, and a push piece pressed down by a spring 9 is inserted into both recesses 8 as shown in FIG. 10, and insert this push piece 10 into the guide hole 3.
, and the front part of the clamp claw 5 is pushed up by the reaction force.

Reference numeral 12 denotes a receiving plate which is fixed to the lower front part of the main body 2 and whose upper edge protrudes towards the lower part of the front opening of the guide hole 3, and as shown in FIGS.
A tubular slider 16 that is pushed forward by a spring 15 is fitted into a concave hole 14 formed rearward from the front end of the lower bulging portion 13 . By crimping the clamp claw 5, the reaction force pushes the clamp claw 5 backward.

18 is a horizontal cam hole provided near the rear end of the main body 2 so as to be orthogonal to the guide hole 3; a cam shaft 19 having square shaft portions 17 at both ends is rotatably fitted into this cam hole; The main body 2 is placed in a part of the circumferential groove 22.
The protrusion on the inner end of the retaining screw 23 screwed into is engaged.

A circular cam 20 is provided at the center of the camshaft 19, and equiangular spiral cams 21 are provided on both sides of the cam 20, and the radius of the cam 21 is shortened by a certain length at each certain angle.

A notch 24 having a predetermined depth is provided from the rear end of the clamp claw 5 so that the outer periphery of the notched cam 20 is loosely fitted into this notch 24. A lever 25 located at the front part of the lever 25 is loosely fitted, and its upper end is attached to the clamp claw 5 with a pin 26 so as to swing back and forth, and its lower end is fitted into the engagement hole 27 provided at the bottom of the guide hole 3. engage in a state with a certain amount of play.

Further, the left and right cams 21 are brought into contact with the rear lower surface of the clamp claw 5, that is, the portions on both sides of the notch 24.

Furthermore, a notch 24 at the rear end of the clamp claw 5
A pair of left and right recessed holes 28 of a predetermined depth are formed from the top surface of both sides of the recessed holes 28 as shown in FIG.
A push piece 30 pushed up by a spring 29 is fitted into the inside of the
This pushing piece 30 is pressed against the upper surface of the guide hole 3, and the rear end portion of the clamp claw 5 is pushed down by the reaction force.

In the above embodiment, FIG.
At this time, the straight part of the occluded cam 20 of the camshaft 19 is against the lever 25, so the front part of the clamp claw 5 is raised by the action of the spring 9, and its tip is It almost coincides with the front end of the main body 2. Therefore, the protruding edge 32 of a press mold or the like can be placed on the substrate 1 without being hindered by the clamp claws 5.

Next, the square holes of the handle are fitted into the square shaft portions 17 at both ends of the camshaft 19, and the camshaft 19 is rotated in the direction of the arrow in FIG.

When the camshaft 19 begins to rotate in this manner, the lever 25 is first pushed forward by the occluded cam 20, and the clamp pawl 5 is advanced against the spring 15, causing its front end to protrude onto the projecting edge 32.

In this way, when the clamp claw 5 moves forward and the circumference of the cam 21 comes into contact with the lever 25, the clamp claw 5 stops moving forward, but the equiangular helical cam 21 continues to move forward at the lower part near the rear end of the clamp claw 5. As a result, the clamp claw 5 rotates about the fulcrum member 6 while compressing the spring 9, and its front end presses onto the flange 32 as shown in FIG. 3 and presses it onto the substrate 1.

Furthermore, when the camshaft 19 is rotated in the opposite direction from the clamped state shown in FIG.
As a result of the reversal of the
It rises due to the action of , and separates from the flange 32 .

Until the action of the equiangular helical cam 21 is completed, the clamp pawl 5 does not move back due to the circumferential portion of the occluded cam 20, but when the action of the equiangular helical cam 21 is finished, the clamp pawl 5 closes the clamp as described above. When released, the straight part of the occluded cam 20 is now connected to the lever 25.
5, the clamp claw 5 is moved back by the spring 15 and returns to the state shown in FIG.

In the above embodiment, the fulcrum member 6 in the form of a broken sphere is used as the fulcrum of the clamp claw 5, but any other means can be used instead, such as using a horizontal shaft and a long hole. In addition to the method of manually rotating the camshaft 19, it is also possible to use a power drive method such as a rotary actuator.

〔effect〕

As mentioned above, this idea is that before clamping, the front part of the clamp claw retracts from the front end of the main body or is in the same position as the front end of the main body, so the press mold etc. can be placed on the board without being interfered with by the clamp claw. This makes it easy to attach and detach press molds, etc.

In this design, as the cam rotates, the missing circular cam pushes the lever in front of it and advances the clamp pawl, so the clamp pawl can move forward extremely smoothly, and after the clamp pawl moves forward, the camshaft can be further rotated. The square helical cam works to push up the rear part of the clamp claw, so the clamping operation can be performed very smoothly and effortlessly.

In addition, the upper end of the lever is connected to a clamp claw, the lower end of the lever is engaged with an engagement hole provided at the bottom of a guide hole provided in the main body, and the middle part of the lever is pushed by an equiangular helical cam. Because of this, the amount of extrusion of the clamp pawl is larger than when pressing the clamp pawl directly with a circular cam, and the flange of the press mold can be securely fixed.

Furthermore, in this invention, the upper end of the lever is swingably connected to the notch in the rear center of the clamp pawl, and equiangular helical cams are provided on both sides of the missing circular cam of the camshaft, so that when the clamp pawl moves forward, The lever pushes the center of the clamp jaw forward, so the clamp jaw moves forward correctly and smoothly without breaking.Also, the left and right equiangular helical cams push the rear lower surface of the clamp jaw located on both sides of the notch of the clamp jaw. Since it pushes up, the clamp claw can swing smoothly. Moreover, with this design, the clamp claw can be moved forward and backward and tightened or released simply by rotating one camshaft, so there is no need for a hydraulic cylinder, and unlike the hydraulic cylinder type, the clamp does not naturally release due to oil pressure leakage. There is no such fear, and even when driven by a hydraulic rotary actuator, there is no risk of spontaneous release due to oil pressure leakage.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an embodiment of the clamp device of this invention, Fig. 2 is a front view of the same as above, Fig. 3 is a vertical side view taken along line A-A in Fig. 1, and Fig. 4 is a camshaft installation. FIG. 5 is a longitudinal sectional side view when the clamp claw is retracted. 1... Board, 2... Main body, 3... Guide hole, 5
... Clamp claw, 9, 15, 29 ... Spring, 18
... cam hole, 19 ... cam shaft, 20 ... missing circular cam, 21 ... equiangular spiral cam.

Claims (1)

[Scope of utility model registration request] A guide hole in the front and back direction is provided in the main body fixed on the board, and a clamp claw that can move forward and backward and swing is fitted into this guide hole, and a spring that acts in a direction to retract the clamp claw and a front part of the clamp claw are inserted into the guide hole. A rotatable camshaft is attached to the cam hole provided in the main body so as to be perpendicular to the guide hole, and the camshaft has a circular ring concentric with the camshaft. A notched circular cam consisting of a circumferential portion and a recessed portion cut out in a straight line in a part of the circumference is provided, and equiangular spiral cams are provided on both sides of the cam, and the notched portion is directed forward from the center of the rear end of the clamp claw. The lower end of the lever, the upper end of which is swingably connected to the front of the notch, is engaged with the engagement hole provided at the bottom of the guide hole, so that the lever is positioned in front of the omitted circular cam. , the rear lower surfaces of the clamp pawl located on both sides of the cut portion of the clamp pawl are brought into contact with the upper side of the both equiangular spiral cams, and when the clamp pawl is in the retracted position, the straight portion of the occluded cam is brought into contact with the lever. A clamping device in which the omitted circular cam and both the equiangular helical cams are positioned so that they face each other and the shortest radius portions of the equiangular helical cams are on the upper side.