JP2003285233A - Apparatus for confirming operation of clamping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic clamping device, which is not only able to judge clamping conditions based on a signal detected by a pressure switch provided in an oil passage when clamping an object to be clamped, but also able to surely confirm the clamping conditions. <P>SOLUTION: A first hydraulic pressure generating cylinder 13 is located in a clamping oil passage 5a for transmitting hydraulic pressure from a hydraulic pump 10 to a clamping oil chamber 2a of a clamping device 2. The hydraulic pressure generated in a secondary chamber 33 of the cylinder 13 by transmitting hydraulic pressure to a primary chamber 32 of the cylinder 13 is transmitted to the clamping oil chamber 2a. A second hydraulic pressure generating cylinder 14 is located in an unclamping oil passage 5b for transmitting hydraulic pressure from a hydraulic pump 10 to an unclamping oil chamber 2b. The hydraulic pressure generated in a secondary chamber 43 of the cylinder 14 by transmitting hydraulic pressure to a primary chamber 42 of the cylinder 14 is transmitted to the unclamping oil chamber 2b. Magnetic proximity switches 15, 16 are provided to detect the positions of the pistons 31, 41 with respect to the cylinder bodies of the first and second hydraulic pressure generating cylinders 13, 14. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation confirmation device for a clamp device, and more particularly to a device capable of confirming the clamp operation and the unclamp operation not from the hydraulic pressure but from the amount of oil actually filled in the clamp device.

[0002]

2. Description of the Related Art Conventionally, various hydraulic clamp devices have been put to practical use in order to fix a work, a mold, and the like so that they can be released. For example, in a machining factory, the work pallet for fixing the workpiece to be machined is
A plurality of hydraulic clamp devices are provided, and a coupler for disconnecting or connecting the hydraulic supply passage is provided in the hydraulic supply passage.

At the work preparation station, one or a plurality of works are set on the work pallet, and the respective works are fixed by one or a plurality of clamping devices, the coupler is divided, and the work pallet is moved onto the table of the machining center. Machine the workpiece.

When the work is fixed to the work pallet, a pressure switch is provided in an oil passage for supplying a hydraulic pressure to the clamp oil chamber of the clamp device in order to detect whether or not the work is fixed by the clamp device. The technology to detect the clamp operation by the switch was adopted. Similarly,
When the work is removed from the work pallet, a pressure switch is provided in the oil passage that supplies hydraulic pressure to the clamp release oil chamber of the clamp device to detect whether the clamp device has released the clamp. The technique of detecting the operation was adopted.

In addition, in the case of a hydraulic clamp device for clamping a die in a press machine or an injection molding machine,
It is the actual situation that the clamp operation and the clamp release operation are detected by almost the same technique as described above. However, the technique of providing a proximity switch or the like for detecting the clamp operation and the clamp release operation in the clamp device is also put to practical use.

[0006]

As described above, in the technique of detecting the clamp hydraulic pressure of the clamp device with the pressure switch, it is not possible to directly detect the operation of the hydraulic cylinder of the clamp device. It only detects the clamp operation. In the case of the work pallet, if the position of the work to be clamped is displaced toward the clamp output part of the clamp device, the clamp output part collides with the work during clamping and pushes the work before clamping. Will be done.

When the work to be clamped is large,
When the clamp output part collides with the work as described above, the hydraulic pressure in the clamp oil passage instantaneously increases in a pulsed manner, the pressure switch operates in response to the hydraulic pressure, and the hydraulic pressure is detected based on the pressure switch detection signal. The supply will be stopped. On the other hand, when there is a foreign object near the workpiece to be clamped and the workpiece and the foreign object are clamped together, the hydraulic pressure in the clamp oil passage rises and the pressure switch operates in response to that hydraulic pressure. The hydraulic pressure supply is stopped based on the detection signal of. As a result, there is a problem that the coupler is divided and the workpiece is machined while the workpiece is not completely fixed, and the cutting tool is damaged or the workpiece becomes a defective product.

When the clamp device is provided with a proximity switch or the like for detecting the clamp operation and the clamp release operation, the number of lead wires extending to the clamp device increases, and in the clamp device applied to the work pallet, the plurality of lead wires are divided. Such as the need for an electrical coupler for connecting and connecting, and the need to change the mounting position of the switches because the operating stroke of the clamp device changes each time the size or shape of the workpiece changes. There's a problem.

An object of the present invention is to provide an operation confirmation device for a clamp device in which the clamp operation of a hydraulic clamp device can be detected from the amount of oil supplied to the clamp oil chamber. To provide an operation confirmation device for a clamp device that can detect the amount of oil supplied.

[0010]

According to a first aspect of the present invention, there is provided a clamp device operation confirmation device, wherein in a hydraulic clamp device that is operated by a hydraulic pressure supplied from a hydraulic supply source, hydraulic pressure is supplied to a clamp oil chamber of the clamp device. A first hydraulic pressure generating cylinder having a cylinder body, a piston member housed therein, and a primary chamber and a secondary chamber on both sides of the piston member, in the clamp oil passage, wherein the hydraulic pressure is supplied from the hydraulic pressure supply source. Is provided in the primary chamber, and a first hydraulic pressure generation cylinder for generating the hydraulic pressure to be supplied to the clamp oil chamber of the clamp device in the secondary chamber is provided.

When clamping the object to be clamped by the clamping device, if the hydraulic pressure is supplied from the hydraulic pressure supply source to the primary chamber of the first hydraulic pressure generating cylinder, the piston member of the first hydraulic pressure generating cylinder moves and moves to the secondary chamber. Since hydraulic pressure is generated and supplied to the clamp oil chamber of the clamp device, the object to be clamped is clamped.

The movement amount of the clamp operation of the clamp device is
Since there is a correspondence relationship with the movement amount of the piston of the first hydraulic pressure generating cylinder, some sort of clamp detection means for detecting the position of the piston of the first hydraulic pressure generating cylinder when the clamp device is in the clamp operating state should be provided. This makes it possible to confirm the clamp operation of the clamp device. The clamp detection means is, for example, an annular permanent magnet attached to a piston member, and a magnetic proximity switch attached to the outer surface of the cylinder body so that the position can be changed,
It can be configured by a magnetic proximity switch or the like that is sensitive to the magnetism of the permanent magnet of the piston.

According to a second aspect of the present invention, in the apparatus for confirming the operation of the clamp device according to the first aspect, the cylinder main body and the inside thereof are housed in a clamp release oil passage for supplying hydraulic pressure to the clamp release oil chamber of the clamp device. A second hydraulic pressure generation cylinder having a piston member and a primary chamber and a secondary chamber on both sides of the piston member, wherein the primary chamber receives the hydraulic pressure supplied from the hydraulic pressure supply source and the unclamping oil chamber of the clamp device. It is characterized in that a second hydraulic pressure generating cylinder for generating a hydraulic pressure to be supplied to the secondary chamber is provided.

When the object to be clamped which has been fixed by the clamp device is released, the first hydraulic pressure generating cylinder 1
When the hydraulic pressure is supplied from the hydraulic pressure supply source to the primary chamber of the second hydraulic pressure generating cylinder while discharging the hydraulic pressure of the secondary chamber, the piston member of the second hydraulic pressure generating cylinder moves and the hydraulic pressure is generated in the secondary chamber to clamp it. Since the oil is supplied to the unclamping oil chamber of the device, the object to be clamped is unclamped.

Since the amount of movement of the clamp device for releasing the clamp is in correspondence with the amount of movement of the piston of the second hydraulic pressure generation cylinder, the piston of the second hydraulic pressure generation cylinder when the clamp device is in the unclamped state. It is possible to confirm the clamp release operation of the clamp device by providing some clamp release detection means for detecting the position. The clamp release detecting means may be the same as the clamp detecting means.

Here, it is desirable to adopt the following various configurations. When a configuration is provided in which clamp detecting means is provided for detecting that the clamp device is in the clamped state from the position of the piston member with respect to the cylinder body of the first hydraulic pressure generating cylinder (claim 3), this clamp detecting means is used. Can adopt the same one as described in the section of the above-mentioned claim 1, from the position of the piston member with respect to the cylinder body, which changes in accordance with the amount of oil filled in the clamp oil chamber of the clamp device. , The clamp operation can be detected reliably.

In the case of adopting a configuration (claim 4) in which clamp release detecting means is provided for detecting that the clamp device is in the unclamped state from the position of the piston member with respect to the cylinder body of the second hydraulic pressure generating cylinder, As the clamp release detecting means, the same one as described in the section of the above-mentioned claim 2 can be adopted, and the cylinder that changes corresponding to the amount of oil filled in the clamp releasing oil chamber of the clamp device From the position of the piston member with respect to the main body,
Clamp release operation can be reliably detected.

In the case of adopting a constitution in which the secondary chamber of the first hydraulic pressure generating cylinder is provided with the first oil supplementing means capable of supplementing oil (claim 5), the first oil supplementing means causes the first hydraulic pressure generating cylinder to operate. The secondary chamber can be refilled with oil. The second
When the second oil replenishing means capable of replenishing oil in the secondary chamber of the oil pressure generating cylinder is used (claim 6), the second oil replenishing means is used to add oil to the secondary chamber of the second oil pressure generating cylinder. Can be replenished.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. The present embodiment is an example in which the present invention is applied to a hydraulic clamp system having a work pallet for fixing a work to be machined by a machine tool and a hydraulic clamp device provided on the work pallet. .

As shown in FIG. 1, the work pallet 1 of the clamp system is provided with, for example, two hydraulic clamp devices 2, and the clamp device 2 clamps the clamp output section 3 by a double-acting hydraulic cylinder. Or
It is designed to operate to release the clamp. A hydraulic pressure supply device 4 is provided outside the work pallet 1, and four hydraulic hoses 5 a, 5 extending from the hydraulic pressure supply device 4 are provided.
b, 6a and 6b are connected to four oil passages in the work pallet 1 through four couplers 7.

As shown in FIG. 1, in the work preparation station, the work W is set on the work pallet 1 in a state where the four couplers 7 are connected and the hydraulic pressure supply device 4 is connected to the two clamp devices 2. As shown in FIG. 2, the two clamp devices 2 are switched to the clamp state to fix the work W, and then the four couplers 7
After that, the work W and the work pallet 1 are conveyed onto the table of the machine tool, and the work W is machined with the work pallet 1 fixed to the table.

As shown in FIG. 3, the hydraulic pressure supply device 4 actually supplies the hydraulic pressure to the two clamp devices 2. However, in FIG. 3, the hydraulic pressure is supplied to and discharged from one clamp device 2. A hydraulic circuit is shown for this purpose. However,
A hydraulic circuit for supplying and discharging hydraulic pressure to the other one clamp device 2 is also provided, but is not shown. However, a configuration may be adopted in which the hydraulic pressure is supplied to or discharged from the other one clamp device 2 by an oil passage branched from the oil passage between the illustrated clamp device 2 and the coupler 7.

The hydraulic pressure supply device 4 includes a hydraulic pump 10 (hydraulic pressure supply source), an electromagnetic directional control valve 11, first and second hydraulic pressure generating cylinders 13 and 14, an oil tank 17 as oil replenishing means,
18 and electromagnetic on-off valves 19 and 20, a control device 21, an operation panel 22 and the like. The illustrated hydraulic pump 10 is driven by an electric motor 11, but a hydraulic pump driven by pressurized air may be applied. Alternatively, other hydraulic pressure supply means may be adopted.

An electromagnetic directional control valve 12 and a first hydraulic pressure generating cylinder 13 are provided in a clamp oil passage 5a which communicates from the hydraulic pump 10 to the clamp oil chamber 2a of the clamp device 2. An electromagnetic direction switching valve 12 and a second hydraulic pressure generation cylinder 14 are provided in the clamp release oil passage 5b communicating with the clamp release oil chamber 2b.

The first hydraulic pressure generating cylinder 13 includes a cylinder body 30 made of a non-magnetic metal material, a movable piston 31 made of a non-magnetic metal material therein, a primary chamber 32 and a secondary chamber partitioned by the movable piston 31. Chamber 33, movable piston 31
It has a compression spring 34 that elastically biases toward the next chamber 32, a magnetic proximity switch 15 (clamp detection means), and the like. The primary chamber 32 of the first hydraulic pressure generating cylinder 13 is connected to the hydraulic pump 10 via the electromagnetic directional control valve 12 by the clamp oil passage 5a, and the secondary chamber 33 is clamp oil chamber 2a of the clamp device 2 by the clamp oil passage 5a. It is connected to the. The first hydraulic pressure generation cylinder 13 has a structure in which the hydraulic pressure supplied from the hydraulic pump 10 is received in the primary chamber 32 and the hydraulic pressure supplied to the clamp oil chamber 2a is generated in the secondary chamber 33.

The second hydraulic pressure generating cylinder 14 comprises a cylinder body 40 made of a non-magnetic metal material, a movable piston 41 made of a non-magnetic metal material inside thereof, a primary chamber 42 and a secondary chamber partitioned by the movable piston 41. 43, a compression spring 44 that elastically biases the movable piston 41 toward the primary chamber 42, a magnetic proximity switch 16 (clamp release detection means), and the like. Second
The primary chamber 42 of the hydraulic pressure generating cylinder 14 is connected to the hydraulic pump 10 via the electromagnetic directional control valve 12 by the clamp release oil passage 5b.
The secondary chamber 43 is connected to the clamp release oil chamber 2b of the clamp device 2 by the clamp release oil passage 5b. The second hydraulic pressure generation cylinder 14 has a structure in which the hydraulic pressure supplied from the hydraulic pump 10 is received in the primary chamber 42 and the hydraulic pressure supplied to the clamp release oil chamber 2b is generated in the secondary chamber 43.

The electromagnetic directional control valve 12 is a hydraulic pump 1
The hydraulic pressure generated at 0 to the first and second hydraulic pressure generation cylinders 13,
It is possible to switch to a position where the primary chambers 32 and 42 of 14 are selectively supplied. The oil filled in the secondary chamber 33 of the first hydraulic pressure generating cylinder 13, the clamp oil passage 5a, and the clamp oil chamber 2a is reduced by a minute amount due to a leak or the like in the clamp device 2 or the coupler 7, so that the oil is replenished. There is a need.

The oil tank 17 for storing replenishing oil is
Oil passage 17a and electromagnetic opening / closing valve 1 capable of opening and closing this oil passage 17a
It is connected to the secondary chamber 33 of the first hydraulic pressure generating cylinder 13 via 9 so that the oil can be replenished from the oil tank 17 to the secondary chamber 33. That is, the oil tank 17, the oil passage 17a, and the electromagnetic opening / closing valve 19 correspond to the first oil replenishing means. Similarly, the oil tank 18 includes a second hydraulic pressure generation cylinder 14 through an oil passage 18a and an electromagnetic opening / closing valve 20 capable of opening / closing the oil passage 18a.
Is connected to the secondary chamber 43 of the
The oil can be replenished. That is, the oil tank 18, the oil passage 18a, and the electromagnetic opening / closing valve 20 correspond to the second oil replenishing means.

The control device 21 is electrically connected to the electric motor 11 for driving the hydraulic pump 10, the electromagnetic directional control valve 12, the electromagnetic opening / closing valves 19 and 20, the magnetic proximity switches 15 and 16, and the operation panel 22. ing. The control device 21
It has an input / output interface, a microcomputer, a drive circuit for driving the electric motor 11, three drive circuits for the electromagnetic directional control valve 12 and the electromagnetic on-off valves 19, 20, and the like, and commands from the operation panel 22 and magnetic proximity switches. 1
Based on the detection signals from 5 and 16, the operation and stop of the electric motor 11 are controlled, and the electromagnetic direction switching valve 12 and the electromagnetic on-off valves 19 and 20 are switched and controlled.

As shown in FIGS. 3 to 5, a ring-shaped permanent magnet 31a is attached to the movable piston 31 of the first hydraulic pressure generating cylinder 13, and the magnetic field of the permanent magnet 31a is changed by the magnetic proximity switch 15. By detecting, the movable piston 31 can be detected. The clamp position where the clamp output part 3 of the clamp device 2 clamps the work W (see FIG.
The position of attachment of the magnetic detection switch 15 is set in advance according to the workpiece W to be clamped so that the magnetic detection switch 15 detects the permanent magnet 31a of the movable piston 31 when the magnetic detection switch 15 descends. It However, when the type of the workpiece W to be clamped is changed, the position of the movable piston 31 when the clamp device 2 is in the clamped state is also changed, so that the magnetic proximity switch 15 is attached to the cylinder body 30 in the direction of movement of the fixer. The position can be changed.

In FIG. 4, the clamp device 2 is in the unclamped state, and the movable piston 3 of the first hydraulic pressure generating cylinder 13 is shown.
1 shows a state in which 1 is reset to the right limit position (initial position). In this state, the oil replenishment port 17b is
To the oil tank 17 by opening the electromagnetic on-off valve 19
The secondary chamber 33 is refilled with oil. When the clamp device 2 is clamped, the electromagnetic opening / closing valve 19 is closed,
The hydraulic pressure is supplied from the hydraulic pump 10 to the primary chamber 32 via the oil passage 5a, and the hydraulic pressure generated in the secondary chamber 33 is supplied to the clamp oil chamber 2a. When the clamp device 2 is in the clamped state, the movable piston 31 moves to the left limit position and the magnetic detection switch 15 moves the movable piston 31 as shown in FIG.
The magnetic field of the permanent magnet 31a is detected so as to face the permanent magnet 31a, and the detection signal is output to the control device 21. The annular seal members 3 located on both sides of the oil refill port 17b
0a and 30b are also provided.

The second hydraulic pressure generating cylinder 14 has the above-mentioned first
Since it has the same structure as the hydraulic pressure generation cylinder 13,
An illustration is omitted and a brief description will be given. Second hydraulic pressure generation cylinder 14
The movable piston 41 of is provided with a ring-shaped permanent magnet, and the magnetic field of the permanent magnet is applied to the magnetic proximity switch 16
It is possible to detect the movable piston 41 and to change the mounting position of the magnetic proximity switch 16 with respect to the cylinder body 40 in the direction of movement of the fixer. The mounting position of the magnetic proximity switch 16 is such that the magnetic proximity switch 16 detects the permanent magnet of the movable piston 41 when the clamp output unit 3 of the clamp device 2 moves up to the unclamping position (the position indicated by the solid line in FIG. 3). Is preset according to the workpiece W to be clamped.

Next, the operation of the hydraulic clamp system described above will be described. First hydraulic pressure generation cylinder 13
Thereby disconnecting the clamp oil passage 5a between the hydraulic pump 10 and the clamp oil chamber 2a of the clamp device 2,
The amount of movement of the clamp operation (the amount of movement of the clamp output unit 3,
That is, the movement amount of the piston of the hydraulic cylinder inside the clamp device 2 can be converted into the movement amount of the movable piston 31 of the first hydraulic pressure generation cylinder 13. Then, the fact that the clamp device 2 is in the clamp operating state is confirmed by the magnetic proximity switching 15 by the first hydraulic pressure generating cylinder 1
The position of the movable piston 31 with respect to the cylinder body 30 of No. 3 can be reliably detected.

Similarly, the second hydraulic pressure generation cylinder 14 divides the clamp release oil passage 5b between the hydraulic pump 10 and the clamp release oil chamber 2 of the clamp device 2, and the movement amount of the clamp release operation of the clamp device 2 ( The movement amount of the clamp output unit 3, that is, the movement amount of the piston of the hydraulic cylinder inside the clamp device 2) can be converted into the movement amount of the movable piston 41 of the second hydraulic pressure generation cylinder 14. Then, the fact that the clamp device 2 is in the unclamped state can be reliably detected from the position of the movable piston 41 with respect to the cylinder body 40 of the second hydraulic pressure generation cylinder 14 by the magnetic proximity switching 16.

In this work preparation sitation, when hydraulic pressure is supplied to the clamp oil chamber 2a of the clamp device 2 to clamp the work W, when the clamp oil chamber 2a is filled with a sufficient hydraulic pressure to be in a clamped state, the The proximity switch 15 detects the movable piston 31. Even if the position of the work W before clamping is displaced or even if foreign matter is clamped together with the work W, the first hydraulic pressure generating cylinder 13
The magnetic proximity switch 15 does not detect the movable piston 31 unless a predetermined amount of oil pressure is supplied from the secondary chamber 33 to the clamp oil chamber 2a to bring about an actual clamped state. That is, it is possible to easily determine that the clamped state has been reached from the detection signal of the magnetic proximity switch 15.

This is also the case when the clamp of the work W is released, and unless the hydraulic pressure of a predetermined amount is supplied to the clamp release oil chamber 2b of the clamp device 2 and the actual clamp release state is reached. The magnetic proximity switch 16 does not detect the movable piston 41. That is, it can be easily determined from the detection signal of the magnetic proximity switch 16 that the clamp is released.

As described above, since the first hydraulic pressure generating cylinder 13 and the magnetic proximity switch 15 are provided so that it is possible to reliably detect that the clamp device 2 is in the clamped state, the cutting tool of the machine tool is erroneously determined to be clamped. It is possible to solve the problem of damaging the workpiece and making the work W a defective product. Further, since the second hydraulic pressure generating cylinder 14 and the magnetic proximity switch 16 are provided to reliably detect that the clamp device 2 is in the unclamped state, erroneous determination of unclamping can be prevented.

Oil tanks 17 and 18 serving as first and second hydraulic pressure replenishing means, electromagnetic on-off valves 19 and 20, oil passages 17a and 18
Since a is provided, the first and second hydraulic pressure generation cylinders 13, 1
Since the secondary chambers 33 and 43 can be replenished with oil every time the movable pistons 31 and 41 of No. 4 return to the right limit position, the secondary chambers 33 and 43, the oil passages 5a and 5b, and the clamp oil chamber 2a. It is possible to reliably prevent a malfunction due to a nok of oil on the side of the clamp release oil chamber 2b.

Next, an example in which the above embodiment is partially modified will be described. 1) In the above-described embodiment, the clamp system including the work pallet 1 and the plurality of hydraulic clamp devices 2 has been described as an example, but the object to be clamped (workpiece, mold, tool, etc.) can be clamped or unclamped. The present invention can be applied to at least one hydraulic clamp device.

2) The first hydraulic pressure generating cylinder 13 and the second
The hydraulic pressure generation cylinder 14 may be integrally configured. Further, the oil tank 17, the electromagnetic opening / closing valve 19, and the first hydraulic pressure generating cylinder 13 may be integrally formed, and the oil tank 18, the electromagnetic opening / closing valve 20, and the second hydraulic pressure generating cylinder 14 may be integrally formed. May be. 3) Instead of the magnetic proximity switches 151 and 16, a linear scale capable of detecting the movement amount of the pistons 31 and 41, an ultrasonic sensor, or other sensors can be applied. For example, the first and second hydraulic pressure generation cylinders 1
A switch operating piece is provided on a rod that is connected to the movable pistons 31, 41 of 3, 14 and extends through the end walls of the cylinder bodies 30, 40 to the outside, and the switch operating piece is detected by a proximity switch or the like. You may comprise.

[0041]

According to the first aspect of the present invention, the clamp oil passage for supplying the hydraulic pressure to the clamp oil chamber of the clamp device has the first structure.
Since the hydraulic pressure generating cylinder is provided and the hydraulic pressure generated in the secondary chamber of the first hydraulic pressure generating cylinder is supplied to the clamp oil chamber, the hydraulic pressure supply source and the clamp oil of the clamp device are configured by the first hydraulic pressure generating cylinder. The hydraulic supply system between the chambers is divided, and the movement amount of the clamp operation of the clamp device is set to the first
It can be converted into the movement amount of the piston member of the hydraulic pressure generation cylinder. Therefore, by providing some clamp detecting means for detecting the position of the piston of the first hydraulic pressure generation cylinder when the clamp device is in the clamp operating state, it is possible to confirm the clamp operation of the clamp device. Become.

According to the second aspect of the invention, a second hydraulic pressure generating cylinder is provided in the clamp releasing oil passage for supplying hydraulic pressure to the clamp releasing oil chamber of the clamp device, and a second hydraulic pressure generating cylinder is used to generate the secondary hydraulic pressure in the secondary chamber. The second hydraulic pressure generating cylinder separates the hydraulic pressure supply system between the hydraulic pressure supply source and the clamp release oil chamber of the clamp device, so that the clamp release operation of the clamp device is performed. The movement amount can be converted into the movement amount of the piston member of the second hydraulic pressure generation cylinder. Therefore, by providing some clamp release detecting means for detecting the position of the piston of the second hydraulic pressure generation cylinder when the clamp device is in the unclamped state, it is possible to confirm the clamp release operation of the clamp device. It will be possible.

According to the third aspect of the present invention, the clamp detecting means can detect that the clamp device is in the clamped state from the position of the piston member with respect to the cylinder body of the first hydraulic pressure generating cylinder, thereby performing the clamp operation. Can be reliably detected.

According to the fourth aspect of the present invention, the clamp release detecting means can detect that the clamp device is in the clamp release state from the position of the piston member with respect to the cylinder body of the second hydraulic pressure generating cylinder. Clamp release operation can be reliably detected.

According to the invention of claim 5, oil can be replenished to the secondary chamber of the first oil pressure generating cylinder by the first oil replenishing means. According to the invention of claim 6, the second oil replenishing means can replenish the secondary chamber of the second hydraulic pressure generating cylinder with oil.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a hydraulic clamp system (workpiece mounting preparation stage) according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a hydraulic clamp system (clamping completed, coupler disconnected state).

FIG. 3 is a hydraulic circuit diagram of a hydraulic pressure supply device.

FIG. 4 is an enlarged cross-sectional view of a first hydraulic pressure generation cylinder (clamp release operation state).

FIG. 5 is an enlarged cross-sectional view of a first hydraulic pressure generation cylinder (clamping operation state).

[Explanation of symbols]

2 Hydraulic clamp device 2a Clamp oil chamber 2b Clamp release oil chamber 5a Clamp oil passage 5b Clamp release oil passage 10 Hydraulic pump (hydraulic power source) 13, 14 First and second hydraulic pressure generation cylinders 15,16 Magnetic proximity switch 17,18 Oil tank 17a, 18a oil passage 19,20 solenoid valve 32,42 Primary room 33,43 Secondary room

Claims (6)

[Claims] 1. A hydraulic clamp device that operates with hydraulic pressure supplied from a hydraulic pressure supply source, wherein a cylinder body and a piston member housed therein are provided in a clamp oil passage that supplies hydraulic pressure to a clamp oil chamber of the clamp device. And a first hydraulic pressure generating cylinder having a primary chamber and a secondary chamber on both sides of the piston member, the primary chamber receiving hydraulic pressure supplied from the hydraulic pressure supply source,
An operation confirmation device for a clamp device, comprising: a first hydraulic pressure generation cylinder that generates a hydraulic pressure to be supplied to a clamp oil chamber of the clamp device in a secondary chamber. 2. A cylinder main body, a piston member housed in the cylinder main body, and a primary chamber and a secondary chamber on both sides of the piston member are provided in a clamp release oil passage for supplying hydraulic pressure to the clamp release oil chamber of the clamp device. A second hydraulic pressure generation cylinder having a second hydraulic pressure generation cylinder for generating in the secondary chamber a hydraulic pressure that is supplied from the hydraulic pressure supply source to the primary chamber and that is supplied to the clamp release oil chamber of the clamp device. It provided, The operation confirmation apparatus of the clamp apparatus of Claim 1 characterized by the above-mentioned. 3. The clamp detection means for detecting that the clamp device is in a clamped state from the position of the piston member with respect to the cylinder body of the first hydraulic pressure generating cylinder is provided. An operation confirmation device for the described clamp device. 4. A clamp release detecting means for detecting that the clamp device is in an unclamped state from the position of the piston member with respect to the cylinder body of the second hydraulic pressure generating cylinder is provided. The operation confirmation device of the clamp device according to any one of 3 above. 5. The operation confirmation of the clamp device according to claim 1, wherein a first oil replenishing means capable of replenishing oil is provided in the secondary chamber of the first oil pressure generating cylinder. apparatus. 6. The operation confirmation of the clamp device according to claim 2, wherein a second oil replenishing means capable of replenishing oil is provided in the secondary chamber of the second hydraulic pressure generating cylinder. apparatus.