JPH0226591Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention has two clamping states: one in which the balance-type clamp arm is advanced upward and swung forward by a hydraulic cylinder, and the other in which it is swung backward and swung downward Regarding a fluid pressure clamp configured to switch between a retracted state and an unclamped retracted state, this technology not only makes it possible to increase the clamping force of the fluid pressure clamp, but also allows the fluid pressure clamp to be made smaller.

<Prior art> As a prerequisite structure, the present invention has a hydraulic cylinder 13 as shown in FIG. 1 or 14, for example.
The movable side member 1 for supporting the fulcrum with respect to the fixed side member 15 of
7 and a force point driving movable side member 18 are supported so as to be movable up and down, and a fulcrum part 14a is formed at the middle part of the balance-type clamp arm 14, a force point part 14b is at the rear part, and an action point part 14c is formed at the front part. The fulcrum portion 14a of the clamp arm 14 is connected to the movable member 17 for pivoting the fulcrum.
The force point part 14b is connected to the upper output part 18a of the force point driving movable side member 18, and the fulcrum pivot supporting movable side member 17 and the force point driving movable side member 18 are When the clamp arm 14 is moved upward, the clamp arm 14 moves upward and swings forward, resulting in clamp state A. Conversely, when it moves downward, the clamp arm 14 swings backward and swings downward. This example relates to a configuration configured to be in an unclamped retracted state B in which the unclamped retracted state B is retracted.

Conventionally, this prerequisite structure has been configured as shown in Figure 14 (for example, the
57-186238).

That is, the force point driving movable member 1 is formed into a cylindrical shape.
The fulcrum pivot movable member 17 is vertically slidably fitted into the cylindrical hole 18b of No. 8, and the pivot 17a is formed near the center of the upper part of the fulcrum pivot movable member 17. An output portion 18a is formed at a peripheral portion of the movable side member 18 that is spaced rearward from the center. Further, a stopper shaft 70 is made to protrude from the lower surface side of the movable member 17 for pivoting the fulcrum through the bottom wall 18c of the movable member 18 for power point driving and protrudes outside the bottom wall 15d of the fixed member 15. The stopper 71 formed at the lower end of the fixed side member 15
By contacting the bottom wall 15d of the fulcrum, the movable member 17 for supporting the fulcrum is prevented from moving upward by more than a predetermined amount.

<Problems to be solved by the invention> In the conventional structure described above, when pressure fluid is injected into the drive chamber 72 of the fluid pressure actuation cylinder 13, the fulcrum pivot movable member 17 and the force point drive movable member 18 move upward. When the stopper 71 comes into contact with the bottom wall 15d of the fixed side member 15 and the upward movement of the movable side member 17 for supporting the fulcrum is blocked (as shown by the two-dot chain line in Fig. 14a) ), compression coil spring 7
Only the force point driving movable member 18 is further driven upward against the biasing force of 3, thereby swinging the clamp arm 14 forward (FIG. 14b).

In the above case, the operating force E applied from the output part 18a of the movable member 18 for force point driving to the force point part 14b of the clamp arm 14 is the sum of the arm length e of the moment of this operating force E and the moment of the clamping force F. A clamping force F having a value proportional to the arm length f (hereinafter simply referred to as arm ratio e/f) is transmitted from the application point portion 14c to the workpiece W, but there is the following problem.

B. Since the fulcrum pivot movable member 17 is fitted into the cylindrical hole 18b of the force point drive movable member 18, the pivot 17a is moved away from the workpiece W, and from the fulcrum 14a of the clamp arm 14 to the point of action. 14c
As the protrusion dimension increases, the arm length f of the moment increases. Correspondingly, the value of the arm ratio e/f becomes smaller and the clamping force F becomes smaller, which is not preferable for strongly clamping the workpiece W.

B From the movable side member 17 for supporting the fulcrum to the fixed side member 1
Since the hydraulic cylinder 13 becomes longer by the amount that the stopper shaft 70 projects outside the bottom wall 15d of the hydraulic clamp 5, the hydraulic clamp becomes larger.

The object of the present invention is to increase the clamping force of a hydraulic clamp and to make this hydraulic clamp compact.

<Means for Solving the Problems> In order to achieve the above object, the present invention, for example, as shown in FIG. , the movable side member 18 for force point driving is slidably fitted into the cylindrical hole 17b of the movable side member 17 for fulcrum pivoting, and the peripheral edge part forward from the center of the upper part of the movable side member 17 for fulcrum pivoting is fitted. It is characterized in that a pivot portion 17a is formed at the movable side member 18 for force point driving, and an output portion 18a is formed near the center of the upper part of the movable side member 18 for force point driving.

<Operation> According to the present invention, switching from the unclamped retracted state B (shown by the solid line in FIG. 1a) to the clamped state A (shown by the two-dot chain line in FIG. 1a) is performed by the fluid pressure actuated cylinder. 13 through the process shown in FIG. 1b to the state shown in FIG. 1c.

As shown in Figure 1b, a hydraulically actuated cylinder 1
When pressurized fluid such as pressure oil is injected into the drive chamber 21 of No. 3, the movable member 17 for supporting the fulcrum and the movable member 18 for driving the force point move upwardly together with the fixed member 15. Then, when the predetermined stroke L (shown in FIG. 1A) rises, the lower end of the movable member 17 for pivoting the fulcrum moves into the cylindrical hole 1 of the fixed member 15.
The movable member 17 for supporting the fulcrum is prevented from moving upward further, but
The force point driving movable member 18 is allowed to further move upward and forward with respect to the fulcrum pivot movable member 17.

As the pressure fluid continues to be injected into the drive chamber 21, as shown in FIG. The movable member 18 further moves upward. With this, the movable side member 1 for power point driving
The output part 18a of 8 is the fulcrum part 14 of the clamp arm 14.
Centering on a, the force point part 14b is swung upward by the operating force E, and the force point part 14c is swung downward, and the force point part 14c presses the workpiece W from the upper surface side by the clamping force F.

In the above case, since the fulcrum pivot movable member 17 is provided outside the outer periphery of the force point drive movable member 18, the position of the pivot 17a can be brought closer to the workpiece W, and the action can be performed from the fulcrum portion 14a of the clamp arm 14. The protrusion dimension up to the point 14c becomes shorter, and the arm length f of the moment of the clamping force F becomes smaller. From this, the value of the arm ratio e/f becomes large, and the clamping force F is increased to obtain a strong clamping force.

<Example> Hereinafter, an example of this invention will be described with reference to the drawings.

≪First Example≫ 1 to 8 show a first embodiment.

Figures 2 to 4 show a workpiece mounting device using the hydraulic clamp of the present invention, where Figure 2 is a plan view, Figure 3 is an elevation view, and Figure 4 is viewed from the - line arrow in Figure 2. FIG.

In the figure, reference numeral 1 denotes a table of a machining center, on which a blade 3 of an aircraft propeller is fixed via a workpiece attachment device 2, and the surface of this blade 3 is subjected to a grinding process.

The workpiece mounting device 2 consists of an angle-shaped fixture 4 disposed on the left side of the table 1 (left side in Figures 2 and 3) and a workpiece fixing base disposed on the right side (right side in the figures). 5. The base 3a of the blade 3 is fixed to the fixture 4. On the other hand, the workpiece fixing table 5 includes a workpiece support 7 that supports the center part of the lower surface side of the wing part 3b of the blade 3, and a workpiece support 7 that supports the center part of the lower surface side of the wing part 3b of the blade 3.
Push cylinder 8 that supports the peripheral edge on the lower surface side
and a plurality of fluid pressure clamps 9 that press the peripheral edge of the upper wing portion 3b from the upper surface side.
Each of these actuators is hydraulically constructed and is hydraulically operated via a hydraulic unit or a control unit (not shown).

In FIG. 4, reference numeral 10 denotes a grinding wheel, and by appropriately selecting the type and shape of this grinding wheel according to the part to be processed on the blade 3, the upper surface side of the wing portion 3b is ground. In this case, when machining the peripheral edge of the blade part 3b, the hydraulic clamp 9 that presses the machining area from the upper surface side is sequentially switched to an unclamped state so that the grinding wheel 10 does not interfere with the hydraulic clamp. Control is performed so as to make a large retraction from 3.

Hereinafter, the configuration of the above fluid pressure clamp 9 will be explained with reference to FIG. 1 and FIGS. 5 to 8. Fig. 1 is a diagram explaining the operation of the hydraulic clamp 9, Fig. 1a is an elevational view showing the unclamped retracted state, Fig. 1b is an elevational view showing the extended state, and Fig. 1c is an elevational view showing the clamped state. FIG. 5 is an elevational view showing the state of the hydraulic clamp 9.
Rear view, FIG. 6 is a sectional view taken along the - line in FIG. 1a, FIG. 7 is a sectional view taken along the - line in FIG.
FIG. 8 is a sectional view taken along the - line in FIG. 7.

In FIG. 1a, the unclamped retracted state B is shown by a solid line, and the clamped state A is shown by a two-dot chain line.

The fluid pressure clamp 9 is composed of a fluid pressure actuation cylinder 13 whose axis is vertically oriented, and a scale-type clamp arm 14 attached to the upper end of the cylinder 13 for pressing the workpiece W.

First, the fluid pressure actuated cylinder 13 will be explained. It is constructed in a hydraulically driven spring return type, and has a cylindrical fixed side member 15. A cylindrical fulcrum pivot movable member 17 is inserted into the cylindrical hole 15a of the fixed member 15 so as to be movable in the vertical direction.
A force point driving movable member 18 is inserted into the cylindrical hole 17b so as to be movable forward and backward in the vertical direction.

The movable member 17 for supporting the fulcrum has a piston 20 that is slidably fitted into the cylindrical hole 15a of the fixed member 15 in an oil-tight manner. This piston 20
Oil supply and drainage port 2 is located in the drive chamber 21 formed on the lower side of the
The terminal end of 2 is opened. On the other hand, a piston rod 23 is projected from the upper side of the piston 20 to the outside of the upper wall 15c of the fixed side member 15. An annular spring chamber 24 is formed between the outer peripheral surface of the piston rod 23 and the cylindrical hole 15a, and the return movement of the piston 20 is performed by an air spring. That is, the supply/exhaust port 25 formed in the lower part of the fixed side member 15 and the upper part of the spring chamber 24 are communicated with each other through a ventilation passage 27 (shown in FIG. 7), and compressed air is sealed in the spring chamber 24.

Further, the force point driving movable member 18 has a piston 30 that is slidably fitted in an oil-tight manner into the cylindrical hole 17b of the fulcrum pivot movable member 17. It communicates with the drive chamber 21. A piston rod 33 is projected from the upper side of the piston 30 to the outside of the upper end of the movable member 17 for supporting the fulcrum. An annular spring chamber 34 is formed between the outer peripheral surface of the piston rod 33 and the cylindrical hole 17b, and a compression coil spring 36 for returning the piston 30 is mounted in the spring chamber 34. In addition, the spring chamber 34
is communicated with the air spring chamber 24 through a communication passage 38.

The clamp arm 14 is driven upward by the hydraulic cylinder 13, and in this advanced state is clamped and swung forward toward the workpiece W. That is, a fulcrum portion 14a is formed at the intermediate portion of the clamp arm 14 in the longitudinal direction, a force point portion 14b is formed at the rear portion of the clamp arm 14, and an action point portion 14c is formed at the front portion. The fulcrum part 14a is pivotally supported by the upper pivot part 17a of the movable member 17 for supporting the fulcrum, and the fulcrum part 14b is connected to the output part 18a at the upper part of the movable member 18 for power point driving.

The pivot portion 17a is shown in FIGS. 1a, 5 and 8.
It is configured as shown in the figure. That is, a fulcrum pivot frame 40 is screwed and fixed to the upper end of the piston rod 23 of the fulcrum pivot movable member 17.
A pivot pin 41 is horizontally installed on the front side of the peripheral edge of the frame 0. The clamp arm 14 is connected to the fulcrum pivot frame 4.
The pivot pin 41 is slidably fitted into the
It is pivoted so that it can swing back and forth.

On the other hand, the output section 18a is configured as shown in FIG. 1a and FIG. 6. That is, the protruding end of the piston rod 33 of the force point driving movable member 18 is inserted into the loose fitting groove 43 formed at the lower part of the clamp arm 14,
A loose fitting hole 33a at this projecting end is connected to the clamp arm 14 via an output pin 44. Above output pin 4
4 is clamped and fixed between setscrews 45, 45 screwed to both sides of the fulcrum pivot support frame 40. A scraper 46 is attached to the upper part of the fulcrum pivot frame 40 and is attached to the upper swing surface of the clamp arm 14, and a scraper 46 is attached to the lower part of the fulcrum pivot frame 40.
A scraper 47 is formed in sliding contact with the lower swinging surface of.

Further, when the fulcrum pivot movable member 17 is operated with respect to the fixed member 15, a means is provided for preventing the fulcrum pivot movable member 17 from rotating.
That is, as shown in FIGS. 7 and 8, a rotation restriction hole 50 extending vertically is formed in the front corner of the stationary side member 15, and a rotation restriction hole 50 extending from the fulcrum pivot support frame 40 is formed in the rotation restriction hole 50. The rotation restraining shaft 51 is inserted so as to be vertically slidable.

Furthermore, means are provided for detecting the operating state of the hydraulic clamp 9. That is, as shown in FIG. 5, a pair of limit switches 53 and 54 are provided on the rear side of the stationary side member 15 to face each other. The operation of the fluid pressure clamp 9 can be determined by detecting the vertical movement of the actuation rod 55 suspended from the fulcrum pivot frame 40 by the limit switches 53 and 54.

The operation of the fluid pressure clamp 9 having the above configuration is shown in Fig. 1a.
The explanation will be based on items .

Switching from the unclamped retracted state B to the clamped state A is performed by the following procedure. That is, drive chamber 2
When pressure oil is injected into the spring chamber 24, the movable member 17 for supporting the fulcrum and the movable member 18 for driving the force point are raised together against the air pressure in the spring chamber 24. When the fulcrum pivot movable member 17 moves upward by the stroke L, the upper surface side of the piston 20 comes into contact with the reduced diameter portion 15b of the cylindrical hole 15a of the stationary member 15, and further upward movement is prevented (the Figure 1 b). Then, when the injection of pressure oil into the drive chamber 21 is continued, the movable side member 18 for power point drive is further moved upward against the biasing force of the compression coil spring 36, and the output portion 18
a swings the clamp arm 14 toward the clamp side (FIG. 1c).

On the other hand, contrary to the above, switching from the clamped state A to the unclamped retracted state B is performed in the following procedure. That is, when the pressure oil in the drive chamber 21 is discharged,
First, the force point driving movable member 18 is moved downward by the elastic restoring force of the compression coil spring 36 and the pressure of the compressed air in the spring chamber 34, and its output portion 18a returns the clamp arm 14 to the unclamping side and swings it. (Figure 1b). Then, when the pressure oil is continued to be discharged from the drive chamber 21, the movable member 17 for supporting the fulcrum is moved downward by the air pressure in the spring chamber 24, and the unclamp retracted state B is obtained (see Fig. 1). (a solid line diagram).

FIG. 9 to FIG. 13 show other embodiments, and explanations will be given of configurations different from the first embodiment.

<<Second Embodiment>> FIG. 9 shows a second embodiment. In this embodiment, a compression coil spring 26 for returning the piston 20 is installed in a spring chamber 24 formed in the cylindrical hole 15a of the fixed side member 15. In addition, this compression coil spring 2
The spring force of the compression coil spring 36 for returning the piston 30 is set to be stronger than the spring force of the spring 6. That is, the fulcrum pivot movable member 17 moves upward against the biasing force of the compression coil spring 26, and after its advancing movement is blocked by the reduced diameter portion 15b of the cylindrical hole 15a, the fulcrum pivot movable member 17 The spring force is selected so that the force-driving movable member 18 starts moving upward relative to the movable member 17.

Further, an elongated loose fitting hole 57 is formed in the fulcrum portion 14a of the clamp arm 14, and the pivot pin 41 is inserted into the loose fitting hole 57, while the force point portion 14b of the clamp arm 14 is formed in the output pin 44. is supported by

The force point driving movable member 18 is eccentrically fitted into the fulcrum pivot movable member 17, and is thereby prevented from rotating.

<<Third Embodiment>> FIG. 10 shows a third embodiment. In this embodiment, the piston 30 of the force point driving movable member 18 is fitted into a cylindrical hole 17b formed in the upper part of the fulcrum pivot movable member 17. The drive chamber 31 formed below the piston 30 is connected to the drive chamber 21 below the piston 20 via a communication passage 60.
will be communicated to. A compression coil spring 26 having the same structure as that shown in FIG. 9 is installed in the spring chamber 24 above the piston 20.

Moreover, FIG. 11 is a version of the one shown in FIG. 10 which has been further modified as follows. That is, instead of the communication passage 60, the drive chamber 31 below the piston 30 is used.
A dedicated oil supply/drainage port 32 is opened, and a flexible hydraulic hose 61 is connected to the starting end of this oil supply/drainage port 32.
The power point driving movable member 18 is driven by a hydraulic system different from that of the fulcrum pivot movable member 17.

<<Fourth Example>> FIG. 12 shows a fourth example. In this embodiment, a tension coil spring 63 is installed between the lower part of the fixed side member 15 and the upper part of the movable side member 17 for supporting the fulcrum to return the movable side member 17 for supporting the fulcrum. Further, a torsion coil spring 64 is attached to the pivot pin 41, and the clamp arm 14 is urged toward the unclamp side via this torsion coil spring 64. Further, the force point portion 14b of the clamp arm 14 is in direct contact with the output portion 18a of the force point driving movable member 18.

In the above case, the biasing force of the compression coil spring 36 and the torsion coil spring 64 and the biasing force of the tension coil spring 63 are such that the force point driving movable member 18 can move forward after the fulcrum pivot movable member 17 has completed the forward movement. The spring force selection is made to start.

<<Fifth Example>> FIG. 13 shows a fifth example. In this embodiment, the fixed side member 15 is inserted into the lower half of the cylindrical hole 17b of the fulcrum pivot movable side member 17 formed in a cylindrical shape.
The upper part of the piston-shaped power point driving movable side member 18 is fitted into the upper half of the upper cylinder hole 17b.
are fitted, and a drive chamber 66 is formed between the upper end surface side of these fixed side members 15 and the lower surface side of the movable side member 18 for force point driving. Further, a tension coil spring 63 and a torsion coil spring 64 are attached, similar to the one shown in FIG. 12 above. And these springs 6
For the biasing forces 3 and 64, a spring force is selected so that the piston-shaped force point driving movable member 18 starts the advancing operation after the cylindrical fulcrum pivoting movable member 17 completes the advancing operation.

<Effects of the Invention> Since the present invention is constructed and operates as described above, it has the following effects.

(a) Since the movable member for supporting the fulcrum is provided outside the outer periphery of the movable member for driving the force point, the protrusion dimension of the clamp arm from the fulcrum to the point of action can be shortened. Therefore, the arm ratio e/f explained in the <effect section> becomes large, and the clamping force also becomes strong.

(b) Moreover, since the fulcrum pivot movable member is provided outside the outer periphery of the force point drive movable member, the means for preventing the fulcrum pivot movable member from advancing beyond a predetermined amount is provided for the fulcrum pivot member. It becomes easy to form the fitting surface between the movable side member and the fixed side member.
This eliminates the need for the stopper shaft 70 to protrude outside the end wall of the fixed side member as in the conventional example shown in FIG. .

[Brief explanation of the drawing]

Figures 1 to 13 show embodiments of the present invention.
8 to 8 show the first embodiment, FIG. 1 is a diagram explaining the operation of the hydraulic clamp 9, FIG. 1 a is an elevational view showing the unclamped retracted state, and FIG. Fig. 1c is an elevational view showing the clamped state, Fig. 2 is a plan view showing the workpiece mounting device, Fig. 3 is an elevational view thereof, and Fig. 4 is an elevational view showing the clamped state. 5 is a rear view of the hydraulic clamp, FIG. 6 is a sectional view taken along the - line in FIG. 1a, and FIG. 7 is a sectional view taken along the - line in FIG. ,
FIG. 8 is a sectional view taken along the - line in FIG. 7, and FIGS. 9 to 13 are views showing other embodiments, respectively.
FIG. 14 shows a conventional example, FIG. 14a is a diagram showing an unclamped retracted state, and FIG. 14b is a diagram showing a clamped state. 13...Fluid pressure actuation cylinder, 14...Clamp arm, 14a...Fully point part, 14b...Force point part, 1
4c...Action point portion, 15...Fixed side member, 17...
...Movable side member for fulcrum pivot support, 17a...Pivot part, 1
7b... cylinder hole, 18... movable side member for power point drive,
18a... Output section, A... Clamped state, B...
Unclamped evacuation state.

Claims (1)

[Scope of utility model registration request] A movable member 17 for supporting a fulcrum and a movable member 18 for driving a force point are supported by a fixed member 15 of the fluid pressure actuating cylinder 13 so as to be movable up and down. Part 14a,
A force point part 14b is formed at the rear part and an action point part 14c is formed at the front part, and the fulcrum part 14a of the clamp arm 14 is connected to the upper pivot part 17a of the movable side member 17 for supporting the fulcrum.
At the same time, the force point part 14b is connected to the upper output part 18a of the force point driving movable side member 18, and the force point driving movable side member 17 and the force point driving movable side member 18 are moved upwardly. When the clamp arm 14 is moved upward, the clamp arm 14 moves forward and swings forward, which is the clamp state A. Conversely, when it moves downward, the clamp arm 14 moves backward and moves downward, which is the unclamped state A. In the balance type clamp arm retractable hydraulic clamp configured to be in state B, the movable side member 17 for supporting the fulcrum is formed into a cylindrical shape, and the movable side member 17 for supporting the fulcrum is formed in a cylindrical shape.
The movable side member 18 for power point driving is slidably fitted into the cylindrical hole 17b, and the pivot support 17a is attached to the peripheral edge of the movable side member 17 for supporting the fulcrum, which is spaced forward from the center of the upper part of the movable side member 17.
A balance type clamp arm retractable hydraulic clamp characterized in that an output portion 18a is formed near the center of the upper part of a movable side member 18 for force point driving.