JPH11156654A - Clamping device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with troublesome maintenance of spring replacement. SOLUTION: When a piston 43 is lifted, a tapered surface 43h of the piston 43 pressurizes a tapered surface 50d of a clamping pin 50, for moving the clamping pin 50 in a direction of an arrow X. The clamping pin 50 is in press- contact with a float pin 36 for constraining the movement of the float pin 36, so that the float pin 36 is kept press-contact with a work α. When the piston 43 is lowered, a tapered surface 43i of the piston 43 pressurizes a tapered surface 50e of the clamping pin 50. The clamping pin 50 is moved in the opposite direction of the arrow X and separated from the float pin 36. Movement of the float pin 36 is thus allowed. An exclusive spring for retreating the clamping pin 50 is thus dispensed with, for unnecessitating troublesome maintenance such as replacement of the spring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp device for clamping a work by pressing the work against a fixing pin.

[0002]

FIG. 8 shows an example of the above-mentioned clamping device. Here, a plurality of fixing pins 2 are attached to the base 1 (only one is shown), and a work α such as black scale is set on the plurality of fixing pins 2. The work α is a pressing clamp ( (Not shown) against the plurality of fixing pins 2 from above. The movable pin 3 is slidably mounted on the base 1, and as shown by a solid line, the movable pin 3 rises by air pressure and contacts the workpiece α at a predetermined pressure.

In the above configuration, when the rod 4a of the lock cylinder 4 rises, the inclined surface 4b of the rod 4a presses the inclined surface 5a of the restraint clamp 5, and the restraint clamp 5 slides in the direction of arrow X. Then, the restraint clamp 5 is pressed against the movable pin 3 and restrains the slide of the movable pin 3, so that the movable pin 3 is held in a state of being pressed against the work α.

The above-mentioned device is described in Japanese Patent Application No. 9-229431 filed by the present applicant. When the rod 4a of the lock cylinder 4 descends, the restraining clamp 5 causes the restoring force of the spring 6 to move. , And slides away from the movable pin 3, so that the slide of the movable pin 3 is permitted. Therefore, when used for a long period of time, the restoring force of the spring 6 is reduced, which may hinder the sliding of the restraining clamp 5 in the direction indicated by the arrow X. Therefore, the trouble of replacing the spring 6 is required. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a clamp device which requires no troublesome maintenance such as replacement of a spring.

[0006]

According to a first aspect of the present invention, there is provided a clamp device, comprising: a base; a fixing pin provided on the base for supporting a work; and a movable member movably mounted on the base and urged toward the work. A pin, a pressing clamp for pressing the work against the fixed pin and the movable pin,
A restraining clamp provided on the base and capable of moving forward and backward with respect to the movable pin, and a cam mechanism for moving the restraining clamp forward and backward, wherein the cam mechanism is in a state where the work is pressed against the fixed pin and the movable pin. Pressing against the movable pin as the restraining clamp is advanced with
The present invention is characterized in that the restraining clamp is separated from the movable pin with the retreat of the restraining clamp.

According to the above means, when the restraining clamp advances and is pressed against the movable pin, the movement of the movable pin is restrained, and the movable pin is held in a state of being pressed against the work. In this state, when the restraining clamp retreats and separates from the movable pin, the movement of the movable pin is allowed. In this case, since the restricting clamp is advanced and retracted by the cam mechanism, the exclusive spring for retracting the restricting clamp is abolished, and the troublesome maintenance of replacing the spring is not required.

According to a second aspect of the present invention, the cam mechanism has a pair of inclined surfaces provided on the restraint clamp, a piston which moves forward and backward by fluid pressure, and one of the restraint clamps provided on the piston when the piston advances. The present invention is characterized in that it has a pair of inclined surface portions that press the inclined surface portion to advance the restraining clamp and press the other inclined surface portion of the restraining clamp when the piston is retracted to retract the restraining clamp.

According to the above means, when the piston advances, the one inclined surface of the piston presses the one inclined surface of the restraining clamp, so that the restraining clamp advances. When the piston retreats, the other inclined surface of the piston presses the other inclined surface of the restraint clamp, so that the restraint clamp retracts. For this reason, the restraining clamp is stably advanced and retracted in conjunction with the piston with a simple configuration such as an inclined surface portion.

According to a third aspect of the present invention, there is provided a clamp device, wherein a first air injection path and a second air injection path, into which air is injected from an air discharge means, are provided on a base, and the first air injection path is provided with air over the entire surface. The movable pin has a pressure receiving portion for supplying air to the opposite surface through the second air injection path, and the movable pin is urged toward the workpiece by a differential pressure of air acting on both surfaces of the pressure receiving portion. However, it has features. According to the above means, the contact pressure of the movable pin with respect to the work can be adjusted to an appropriate value only by adjusting the air supply pressure from the first air injection path and the second air injection path to the movable pin. It can easily respond to changes in types and processing methods.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. First, in FIG. 3, a manifold 1 is provided inside a machining center (not shown).
1 is provided. The manifold 11 has a plurality of intake and exhaust pipes (not shown) arranged in a group.
An X valve 12, a Y valve 13, and a Z
Valve 14, piston valve 15, float valve 16
Is installed.

A compressor 19 is connected to the manifold 11 via a pressure increasing valve 17 and an FRL unit 18. The former FRL unit 18 includes an oiler 18a that mixes mist oil into the air discharged from the compressor 19, a pressure reducing valve 18b that keeps the pressure of the air discharged from the compressor 19 constant, and purifies the air discharged from the compressor 19. The air that has been processed by the FRL unit 18 is supplied to the manifold 11 through the pressure increasing valve 17.

The reference numeral 11a in FIG.
1 shows a muffler for silencing connected to 1. Also,
The compressor 19 corresponds to the air discharging means according to the third aspect.

A machining table (not shown) is provided inside the machining center. As shown in FIG. 2, a jig plate 20 is mounted on the processing table, and three Z cylinders 21 are mounted on the jig plate 20, as shown in FIG. Each of the Z cylinders 21 is composed of a pneumatic cylinder, and the forward side of each of the Z cylinders 21 is connected to the Z valve 14 via a rotary valve 22, a relay valve 23, and a pressure reducing valve 24.
The return side of each Z cylinder 21 is a speed controller 2
5, is connected to the Z valve 14 via the rotary valve 22.

The Z valve 14 and the relay valve 23 are connected to a control circuit (not shown).
As the states of the valve 14 and the relay valve 23 are switched, the rod 21a of each Z cylinder 21 is moved forward and backward as shown in the following. Air is supplied from the manifold 11 to the forward side of the Z cylinder 21 through the Z valve 14, the pressure reducing valve 24, the relay valve 23, and the rotary valve 22, and the rod 21a is advanced at a low pressure. From manifold 11 to Z valve 14, relay valve 2
3. Air is supplied to the forward side of the Z cylinder 21 through the rotary valve 22 to advance the rod 21a at a high pressure. Air is supplied from the manifold 11 through the Z valve 14, the rotary valve 22, and the speed controller 25 to the reciprocating side of the Z cylinder 21 to retreat the rod 21a.

As shown in FIG. 2, three j-pins 26 are fixed to the jig plate 20, and a work α such as black scale is placed on the three z-pins 26. I have. A Z clamp 2 is attached to the rod 21a of each Z cylinder 21.
6a, the control circuit switches the Z-clamp 26a in the arrow Z direction in conjunction with the advance of each rod 21a in accordance with the switching of the states of the Z-valve 14 and the relay valve 23, as described above and in FIG. Move. Thus, the work α is pressed against the three Z pins 26 by the three Z clamps 26a. Incidentally, the Z pin 26 corresponds to the fixing pin according to the first aspect. Further, the Z clamp 26a corresponds to the pressing clamp according to the first aspect.

An X cylinder 27 is mounted on the jig plate 20, as shown in FIG. The X cylinder 27 is composed of a pneumatic cylinder. The forward side of the X cylinder 27 is connected to the X valve 12 via a pressure reducing valve 28, and the backward side of the X cylinder 27 is connected via a speed controller 29. It is connected to the X valve 12.

The X valve 12 is connected to a control circuit, and the control circuit moves the rod 27a of the X cylinder 27 forward and backward as shown below and in accordance with the switching of the state of the X valve 12. Air is supplied from the manifold 11 to the forward side of the X cylinder 27 through the X valve 12 and the pressure reducing valve 28, and the rod 27a is advanced. Air is supplied from the manifold 11 to the reciprocating side of the X cylinder 27 through the X valve 12 and the speed controller 29 to retreat the rod 27a.

As shown in FIG. 2, two X pins 30 are fixed to the jig plate 20. An X clamp 30a is connected to the rod 27a of the X cylinder 27. As described above, the control circuit switches the state of the X valve 12, and the X clamp 30a interlocks with the advance of the rod 27a. 30a is moved in the arrow X direction. As a result, the work α is
It is pressed against the X pin 30 of the book and positioned in the arrow X direction.

A jig cylinder 31 is mounted on the jig plate 20, as shown in FIG. The Y cylinder 31 is composed of a pneumatic cylinder, and the forward side of the Y cylinder 31 is provided with a rotary valve 22 and a pressure reducing valve 3.
The Y-valve 13 is connected to the Y-valve 13 via a speed controller 33 and the rotary valve 22.

The Y valve 13 is connected to a control circuit. The control circuit moves the rod 31a of the Y cylinder 31 forward and backward as shown below and in accordance with the switching of the state of the Y valve 13. Air is supplied from the manifold 11 to the forward side of the Y cylinder 31 through the Y valve 13, the pressure reducing valve 32, and the rotary valve 22, and the rod 31a is advanced. Air is supplied from the manifold 11 through the Y valve 13, the rotary valve 22, and the speed controller 33 to the reciprocating side of the Y cylinder 31 to retract the rod 31 a.

As shown in FIG. 2, two Y pins 34 are fixed to the jig plate 20. The Y-clamp 34a is connected to the rod 31a of the Y-cylinder 31, and the control circuit switches the state of the Y-valve 13 as described above. 34a is moved in the arrow Y direction. As a result, the work α is
The book is pressed against the Y pin 34 and positioned in the direction of the arrow Y.

The jig plate 20 is provided with two clamp bases 35. Each of these clamp bases 35
Corresponds to a base according to the first aspect. In each clamp base 35, as shown in FIG. 1A, a float pin 36 corresponding to a movable pin according to the first aspect has arrows Z and It is housed so as to be slidable in the direction indicated by the opposite arrow Z. Each of these float pins 36 is, as shown in FIG.
It is composed of a small-diameter main body 36a and a large-diameter pressure receiving part 36b, and a gap for air purging is formed between the outer peripheral surface of each main body 36a and the clamp base 35,
A flat inclined surface portion 36c is formed on an outer peripheral portion of each main body portion 36a.

Each of the clamp bases 35 has a structure shown in FIG.
As shown in FIG.
A first air injection path 35a having a letter shape is formed. Each of these air injection paths 35a is connected to the clamp base 3
5 is formed by engraving a T-shaped passage in 5, and then screwing a screw plug 37 into the passage.
One end of the air injection passage 35 a communicates with the upper surface of the pressure receiving portion 36 b of the float pin 36, and the other end thereof is connected to the clamp base 3.
5 is open through the lower surface.

Each clamp base 35 has a port 38 mounted below the air injection path 35a.
Each of these ports 38 has a cylindrical shape having an air injection passage 38a, and as shown in FIG.
And an FRL unit 18 via a pressure increasing valve 17. Therefore, when the compressor 19 is operated, the clamp base 3 is moved from the air injection path 38a of each port 38.
The air is supplied to the upper surface of the pressure receiving portion 36b through the fifth air injection path 35a. It should be noted that reference numeral 38b in FIG.
Indicates an O-ring for air seal mounted on the port 38.

Each of the clamp bases 35 has a structure shown in FIG.
As shown in FIG. 7, a port 40 is mounted below the float pin 36. Each of these ports 40 is
A cylindrical shape having an air injection path 40a of
As shown in FIG. 3, it is connected to the float valve 16 via the pressure reducing valve 41. Incidentally, reference numeral 40b in FIG.
Indicates an O-ring for air seal mounted on the port 40.

The float valve 16 is connected to a control circuit, and the control circuit moves both float pins 36 up and down as described below and in conjunction with switching the state of the float valve 16. Manifold 11 to float valve 16, pressure reducing valve 4
1, the pressure receiving section 3 through the air injection path 40a of the port 40
Air is supplied to the lower surface of 6b, and as shown by the solid line in FIG. 1B, the float pin 36 is raised against the air pressure from the air supply path 35a. The supply of air to the air injection path 40a of the port 40 is stopped, and the float pin 36 is lowered by the air pressure from the air supply path 35a as shown by a two-dot chain line in FIG.

The main body 36a of each float pin 36 has
As shown in FIG. 4, a flat portion 36d is formed. As shown in FIG. 1C, a locking screw 42 is screwed to each clamp base 35. As shown in FIG. 1 (a), each of the locking screws 42 substantially contacts the flat portion 36d of the float pin 36, and when the float pin 36 moves up and down, the rotation of the float pin 36 Restrain.

A piston 43 is mounted on each clamp base 35 so as to be slidable in the directions indicated by arrows Z and Z. As shown in FIG. 5, each of these pistons 43 has a main body portion 43a having a small diameter and a pressure receiving portion 43b having a large diameter, and grooves 43c and 43d are formed in each main body portion 43a and the pressure receiving portion 43b. And each groove 43c and 4
As shown in FIG. 1A, O-rings 43e and 43f for air sealing are mounted in 3d.

Each clamp base 35 has a piston 43
The port 44 is mounted at a position below the port 44. Each of these ports 44 has a cylindrical shape having an air injection path 44a, and is connected to the piston valve 15 via a pressure reducing valve 45 as shown in FIG.

Each of the clamp bases 35 has a structure shown in FIG.
As shown in FIG. 5, an air injection path 35b that is substantially L-shaped is formed on the side of the piston 43. Each of the air injection paths 35b is formed by engraving a T-shaped passage in the clamp base 35 and then screwing a screw plug 37 into the passage. Is connected to the upper surface of the pressure receiving portion 43b of the piston 43, and the other end is opened through the lower surface of the clamp base 35.

A port 47 is mounted at the lower end of each air injection path 35b. Each of these ports 47 has a cylindrical shape having an air injection path, and is connected to the piston valve 15 via a speed controller 48 as shown in FIG. It should be noted that reference numeral 49 in FIG.
Connect the ports 38, 40, 44, 47 to the clamp base 3
5 shows a lower cover which is prevented from being removed from the bottom cover 5.

The piston valve 15 is connected to a control circuit, and the control circuit moves the piston 43 forward and backward as shown below and in accordance with the switching of the state of the piston valve 15. Manifold 11 to piston valve 15, pressure reducing valve 4
5, the pressure receiving portion 4 through the air injection passage 44a of the port 44
Air is supplied to the lower surface of 3b to move the piston 43 forward (up). The pressure receiving portion 43 is passed from the manifold 11 through the piston valve 15, the speed controller 48, the air injection passage of the port 47, and the air supply passage 35b of the clamp base 35.
Air is supplied to the upper surface of b to move the piston 43 backward (down).

In each of the clamp bases 35, as shown in FIG. 1A, a clamp pin 50 corresponding to the restraint clamp according to the first aspect is housed so as to be slidable in the directions indicated by the arrows X and X. I have. A plate 51 is screwed to each of the clamp bases 35, and each of the plates 51 fixes the clamp pin 50 to the clamp base 35.
Has been stopped from.

As shown in FIG. 6, each clamp pin 50 has a main body 50a having a small diameter and a slide part 50b having a large diameter.
0c is formed. On the inner surface of each notch 50c, two inclined surfaces 50d are formed in the direction of arrow X, and two inclined surfaces 50e are located in the direction opposite to the arrow X.
Are formed.

Each piston 43 has, as shown in FIG.
Two engagement projections 43g located at the upper end of the main body 43a
Are formed at predetermined intervals, and each of the engagement protrusions 43g
Is inserted into the cutout portion 50c of the clamp pin 50 as shown in FIG. Each of these engagement projections 43
As shown in FIG. 5, an inclined surface 43 h is formed on the end surface in the arrow X direction, and an inclined surface 43 i is formed on the end surface in the opposite arrow X direction, as shown in FIG.
3h and 43i are in contact with the inclined surfaces 50d and 50e of the clamp pin 50 as shown in FIG.

As shown in FIG. 6, each of the clamp pins 50 has an inclined surface portion 50f formed at the tip of the main body portion 50a. As shown by a two-dot chain line in FIG.
In a state where each piston 43 is descending in the direction of arrow Z,
Each inclined surface portion 50f is an inclined surface portion 36c of the float pin 36.
Away from When each piston 43 rises in the direction opposite to the arrow Z from this state, the two inclined surfaces 5 h in front of the clamp pin 50 are moved from the two inclined surfaces 43 h in front of the piston 43.
Motor force is transmitted to 0d. Then, the upward linear motion force of the piston 43 is converted into a horizontal linear motion force, and the clamp 50 advances in the arrow X direction.

As shown in FIG. 3, the jig plate 20 has a seating detection hole 20a. The seat detection hole 20a is provided between the speed controller 52 and the pressure reducing valve 5.
3 and connected to the FRL unit 18. When the compressor 19 operates, air is discharged from the seating detection hole 20 a through the pressure reducing valve 53 and the speed controller 52.

A pressure sensor 54 is connected between the seat detection hole 20a and the speed controller 52, and the pressure sensor 54 outputs an electric signal corresponding to the pressure level in the seat detection hole 20a. Further, the X valve 12 and the pressure reducing valve 2
8, a pressure switch 55 is connected, and the Y valve 1
3, a pressure switch 56 is connected between the Z valve 14 and the pressure reducing valve 24, and the X cylinder 27 and the Y cylinder 3 are connected.
When the supply pressure of air to one or three Z cylinders 21 reaches a predetermined value, pressure confirmation signals are output from the pressure switches 55, 56, and 57.

Next, the operation of the above configuration will be described. The work α is placed on the three Z pins 26 and the seating detection hole 2
0a is set above the workpiece α, the seating detection hole 2
The pressure in Oa changes. Then, the control circuit, based on the change in the output signal from the pressure sensor 54, the seat detection hole 2
0a is detected, and the work α has three Z pins 2
6 is set.

When the control circuit determines the setting of the work α, as shown in FIG. 7, the control circuit switches the state of the X valve 12 with a delay of 0.5 seconds from the setting of the work α. Air is supplied to the forward movement side of the cylinder 27. Then, the rod 27 of the X cylinder 27
The X clamp 30a moves in the direction of the arrow X in FIG. 2 in conjunction with the forward movement of "a", and the work α is pressed against the two X pins 30 by the X clamp 30a.

When the control circuit detects that the supply pressure of air to the X cylinder 27 has reached a predetermined value and a pressure confirmation signal has been output from the pressure switch 55, the X clamp 3
0a is determined to have been sufficiently pressed. Then, as shown in FIG. 7, the state of the Y valve 13 is switched with a delay of “1.0” seconds from the output of the pressure confirmation signal, and air is supplied to the forward movement side of the Y cylinder 31. Then, in conjunction with the advance of the rod 31a of the Y cylinder 31, Y
The clamp 34a moves in the direction of arrow Y in FIG.
Is pressed against the two Y pins 34 by the Y clamp 34a.

When the control circuit detects that the supply pressure of air to the Y cylinder 31 has reached a predetermined value and the pressure switch 56 has output a pressure confirmation signal, the Y clamp 3
It is determined that the pressing operation of the work α by 4a has been sufficiently performed. Then, as shown in FIG. 7, the state of the Z valve 14 is switched with a delay of “1.0” seconds from the output of the pressure confirmation signal, and air is supplied to the forward movement side of each Z cylinder 21. Then, the Z clamp 26a moves in the direction of the arrow Z in FIG. 2 in conjunction with the advance of the rod 21a of each Z cylinder 21, and the work α is moved into three Z pins 26 by the three Z clamps 26a.
Pressed to.

When the control circuit detects that the supply pressure of air to the three Z cylinders 21 has reached a predetermined value and that a pressure confirmation signal has been output from the pressure switch 57, the operation of pressing the work α by each Z clamp 26a is performed. Is determined to have been sufficiently performed. Then, as shown in FIG. 7, the float valve 16 is delayed by "1.0" seconds from the output of the pressure confirmation signal.
Of the floating pin 3 through each port 40.
6. Air is supplied to the lower surface of the pressure receiving portion 36b. Then
As shown by a solid line in FIG.
Rises against the air pressure from the air supply passage 35a, and the front end of each body portion 36a contacts the lower surface of the work α at a predetermined pressure.

The control circuit switches the state of the float valve 16 and at the same time starts its own timer, and when the set time of the timer "0.5 seconds" has elapsed, each float pin 36 has sufficiently contacted the work α. Judge. Then, the state of the piston valve 15 is switched, and each port 44
Then, air is supplied to the lower surface of the pressure receiving portion 43b of the piston 43, and each piston 43 is lifted in the direction opposite to the arrow Z.

When each piston 43 rises, as shown by a solid line in FIG. 1 (a), both inclined surfaces 43h in front of the piston 43 are connected to both inclined surfaces 5 in front of the clamp pin 50.
Since 0d is pressed, each clamp pin 50 advances in the arrow X direction. Then, the inclined surface portion 50f at the tip of each clamp pin 50 is pressed against the inclined surface portion 36c of the float pin 36, and the vertical movement of each float pin 36 is restrained, so that each float pin 36 is restrained while being pressed against the work α. Is done.

The control circuit switches the state of the piston valve 15 and simultaneously starts its own timer. Then, when the set time “0.5 seconds” of the timer has elapsed, it is determined that each clamp pin 50 has been sufficiently pressed against the float pin 36, and a machining command signal is output to the machining center. Then, the machining operation is performed on the workpiece α while the tool is automatically changed and the jig plate 20 is moved by the machining table.

"MT" in FIG. 7 indicates the machining time of the work α by the machining center, and the control circuit switches the state of the relay valve 24 while the work α is being machined. Supplies air to the three Z cylinders 21 without passing through the pressure reducing valve 25. Thereby, the work α is pressed against the three Z pins 26 with a strong force, and the position of the work α is prevented from being displaced by an external force during processing.

When the machining of the work α is completed, a machining end signal is output from the machining center to the control circuit. Then, the control circuit switches the state of the X valve 12, and interlocks with the retraction of the rod 27 a of the X cylinder 27 to set the X clamp 3.
0a is moved in the direction opposite to the arrow X in FIG. With this,
The state of the Y valve 13 is switched, and the Y clamp 34a is moved in the direction opposite to the arrow Y in FIG. 2 in conjunction with the retraction of the rod 31a of the Y cylinder 31. At the same time, the state of the Z valve 14 is switched, and the Z clamp 26a is moved in the direction indicated by the arrow Z in FIG. 2 in conjunction with the retraction of the rods 21a of the three Z cylinders 21. Thus, the constraint of the work α by the X clamp 30a, the Y clamp 34a, and the three Z clamps 26a is released.

The control circuit includes the X valve 12 to the Z valve 14
At the same time, the state of the piston valve 15 is switched, and each piston 43 is lowered in the arrow Z direction.
Then, the two inclined surfaces 43i behind the pistons 43 press the two inclined surfaces 50e behind the clamp pins 50, and therefore, as shown by the two-dot chain line in FIG. Slide in the X direction. Then, the inclined surface portion 50f at the tip of each clamp pin 50 separates from the inclined surface portion 36c of the float pin 36, and each float pin 36
Is allowed to move up and down.

The control circuit switches the state of the float valve 16 at the same time as the state of the piston valve 15 is switched, and stops the supply of air to each port 40. Then, as indicated by a two-dot chain line in FIG. 1B, each float pin 36 is lowered by the air pressure from the air supply path 35a, and the main body 36a of each float pin 36 is separated from the work α. 1A is a pair of inclined surfaces 50d and 50e of the clamp pin 50, the piston 43, and a pair of inclined surfaces 43h and 43 of the piston 43.
3c shows a cam mechanism composed of 3i.

According to the above embodiment, the clamp pin 50 is moved toward and away from the float pin 36 as the cam mechanism 58 advances and retreats. For this reason, the clamp pin 5
The exclusive spring for retracting 0 is abolished, and the replacement of the spring becomes unnecessary, so that the maintainability is improved.

The pair of inclined surfaces 43 of the piston 43
By pressing the pair of inclined surfaces 50d and 50e of the clamp pin 50 with h and 43i, the clamp pin 50 is moved forward and backward, so that the clamp pin 50 can be stably moved forward and backward with a simple configuration.

The float pin 36 was urged toward the work α by the differential pressure of the air supplied through the first air injection path 35a and the second air injection path 40a. Therefore, the contact pressure of the float pin 36 with the work α can be adjusted to an appropriate value only by adjusting the air supply pressure to the float pin 36, so that it is possible to easily cope with a change in the type of the work α and the processing method.

Further, since a gap is formed between the clamp base 35 and the float pin 36, even if machining chips or the like try to enter the gap, the dust is discharged by the air pressure from the second air injection passage 40a (air). purge). For this reason, it is prevented that processing dust is clogged in the gap and hindrance of slide of the float pin 36 is prevented, so that the float pin 36 slides smoothly. At the same time, there is no need to mount an O-ring or the like on the outer peripheral surface of the float pin 36 to prevent the intrusion of the processing waste. For this reason, there is no contact resistance between the O-ring and the clamp base 35, so that the float pin 36 slides smoothly from this point as well.

In the above embodiment, the work α is set to Z
After being pressed against the Z pin 26 by the clamp 26a, the float pin 36 is raised in the direction indicated by the arrow Z and pressed against the work α, but is not limited thereto. For example, the following method may be used. The work α is set on the Z pin 26 and the float pin 36 with the float pin 36 raised in the direction indicated by the arrow Z. Then, after moving the Z clamp 26a in the direction of the arrow Z, the work α is pressed against the Z pin 26 and the float pin 36, and then the clamp pin 50 is moved in the direction of the arrow X to press the float pin 36.

In the above embodiment, the float pin 36 is slid in the direction opposite to the arrow Z by the difference between the air pressure from the upper air injection path 35a and the air pressure from the lower air injection path 40a. However, the present invention is not limited to this. For example, the slide may be performed in the direction opposite to the arrow Z only by the air pressure from the air injection path 40a located below.

In the above embodiment, the X valve 1
Although the drive control of the float valve 16 is performed by the control circuit, the present invention is not limited to this. For example, the drive control may be performed by a control device mainly including a microcomputer.

In the above embodiment, the piston 4
The clamp pin 50 is moved forward and backward by pressing the pair of inclined surface portions 50d and 50e of the clamp pin 50 by the pair of inclined surface portions 43h and 43i. However, the present invention is not limited to this. It may be configured as follows.

A groove is formed in a disk that is rotated by a drive source such as a motor. An engaging portion for engaging the groove of the disk is formed on the clamp pin 50, and the rotational force of the disk is transmitted to the clamp pin 50 through the inner surface of the groove and the engaging portion, so that the clamp pin 50 moves forward and backward. Let it.

A forward drive source and a reverse drive source, such as motors, are provided. Then, by transmitting the driving force of the forward drive source to the clamp pin 50 through the plate cam, the clamp pin 50 is advanced, and the drive force of the reverse drive source is transmitted to the clamp pin 50 through another plate cam. Accordingly, the clamp pin 50 is retracted.

[0062]

As is clear from the above description, the clamp device of the present invention has the following effects. According to the first aspect of the present invention, since the restraining clamp is moved forward and backward by the cam mechanism, the exclusive spring for retracting the restraining clamp is eliminated,
The troublesome maintenance of replacing the spring is not required. According to the second aspect of the present invention, since the pair of inclined surfaces of the piston press the pair of inclined surfaces of the restraining clamp, the restraining clamp is advanced and retracted. Done in According to the third aspect of the present invention, the movable pin is urged toward the work by the differential pressure of air. Therefore, the contact pressure of the movable pin with the work can be adjusted to an appropriate value only by adjusting the air supply pressure to the movable pin, so that it is possible to easily cope with a change in the type of the work or the processing method.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of the present invention (a is a sectional view taken along line X1-X1, b is a sectional view taken along line X2-X2, c is X3
View)

FIG. 2A is a top view schematically showing the entire configuration,
(B) is a side view

FIG. 3 is a diagram showing a piping state;

4A is a front view showing a float pin, and FIG. 4B is a top view.

5A is a front view showing a piston, FIG. 5B is a side view, and FIG. 5C is a top view.

6A is a front view showing a clamp pin partially cut away, FIGS. 6B and 6C are side views, and FIG. 6D is a top view.

FIG. 7 is a timing chart for explaining a work clamping operation;

FIG. 8 is a diagram showing a clamp device described in Japanese Patent Application No. 9-229431.

[Description of Signs] α is a work, 19 is a compressor (air discharge means),
26 is a Z pin (fixed pin), 26a is a Z clamp (press clamp), 35 is a clamp base (base), 35a
Is a first air injection path, 36 is a float pin (movable pin), 36b is a pressure receiving section, 40a is a second air injection path,
43 is a piston, 43h and 43i are inclined surfaces, 50
Are clamp pins (restraint clamps), 50d and 50e
Indicates an inclined surface portion, and 58 indicates a cam mechanism.

Claims (3)

[Claims] 1. A base, a fixed pin provided on the base and supporting a work, a movable pin movably mounted on the base and biased toward the work, and a fixed pin and the movable A clamp for pressing against a pin, a restraint clamp provided on the base and capable of moving back and forth with respect to the movable pin, and a cam mechanism for moving the restraint clamp forward and backward. And a clamp device which pushes the restraint clamp forward while being pressed against the movable pin, presses the restraint clamp against the movable pin, and moves the restraint clamp away from the movable pin as it retracts. 2. A cam mechanism comprising: a pair of inclined surfaces provided on a restraining clamp; a piston which advances and retreats by fluid pressure; and a piston provided on the piston, which presses one inclined surface of the restraining clamp when the piston advances. 2. The clamp device according to claim 1, further comprising a pair of inclined surface portions for advancing the restraint clamp and pressing the other inclined surface portion of the restraint clamp when the piston retreats to retract the restraint clamp. 3. A base is provided with a first air injection path and a second air injection path into which air is injected from air discharge means, and the movable pin is provided with air on one surface through the first air injection path. A pressure receiving portion which is supplied and air is supplied to an opposite surface through a second air injection passage, and is urged toward a work side by a differential pressure of air acting on both surfaces of the pressure receiving portion. 2. The clamp device according to 1.