JP2007285365A - Hydraulic system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic system which can detect the end of the lifecycle of an hydraulic pump beforehand which is used for filling an intensifier with a hydraulic fluid. <P>SOLUTION: The hydraulic system is provided with the hydraulic pump 3 and the intensifier 6. The hydraulic pump 3 absorbs and discharges the hydraulic fluid. The intensifier 6 fills the hydraulic fluid, which is discharged from the hydraulic pump 3, into a boost chamber 18, and intensifies the pressure of the hydraulic fluid which fills it. Then the intensifier 6 supplies the hydraulic fluid to the hydraulic cylinders 7A, 7B, 7C side. Then a timer means is provided which is used for measuring the time for filling the hydraulic fluid from the hydraulic pump 3 into the intensifier 6. When the time measured by the timer means exceeds a set time, an alarm is issued. Thus, because the time required for filling the hydraulic fluid from the hydraulic pump 3 into the intensifier 6 exceeds the set time, a worker can recognize that the leakage of the hydraulic fluid from the hydraulic pump 3 is on its way to exceed a normal value, and the end of the lifecycle of the hydraulic pump 3, which is used for filling the intensifier 6 with the hydraulic fluid, can be detected beforehand. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hydraulic device that fills a pressure booster with hydraulic oil discharged from a hydraulic pump and supplies the filled hydraulic fluid to an actuator side from the pressure booster.

This type of hydraulic apparatus includes a hydraulic pump (hydraulic power source), an electric motor, a tank, a pressure intensifier, and the like, and a pressure intensifier is branched and connected to a line connecting the hydraulic pump and an actuator (clamp cylinder). When the workpiece is clamped by the actuator, the hydraulic oil filled in the pressure intensifier is increased from the hydraulic pump by the pressure intensifier, and this increased hydraulic oil is supplied to the actuator, and clamping is performed only by the hydraulic oil from the pressure intensifier. Since there is no need to supply hydraulic oil from the hydraulic pump, the hydraulic pump can be stopped to save energy.
JP 2002-174201 A

  However, in such a conventional hydraulic apparatus, the life of the hydraulic pump cannot be detected, and an abnormal temperature rise of the hydraulic oil due to an increase in leakage of the hydraulic oil from the hydraulic pump causes an abnormality due to the end of the life of the hydraulic pump. Therefore, the preventive maintenance for detecting the life of the hydraulic pump in advance has not been satisfied yet.

  An object of the present invention is to provide a hydraulic device that can detect in advance the end of the life of a hydraulic pump that fills a pressure intensifier with hydraulic oil.

In order to achieve this problem, the present invention has taken the following measures in order to solve the problem. That is,
A time for filling the hydraulic oil from the hydraulic pump to the pressure intensifier with a pump that sucks and discharges the hydraulic oil and a pressure intensifier that fills the hydraulic oil discharged from the pump and supplies the filled hydraulic oil to the actuator side This is a hydraulic device characterized by providing a timer means for measuring the time and issuing an alarm when the time measured by the timer means exceeds a set time.

  In this case, the pressure intensifier is provided with a piston for increasing the operating reason filled from the hydraulic pump and supplying the actuator to the actuator side so that the piston can move to the inside. The timer means is located at the second position with the maximum amount of hydraulic oil charged, and the timer means is charged with hydraulic oil from the hydraulic pump to the pressure intensifier and the first piston is moved from the first position to the second position. You may measure the time which moves to a position. In addition, a supply flow path connecting the pressure intensifier and the actuator side is provided, and an open / close valve for communicating and blocking the supply flow path is provided in the supply flow path, and hydraulic oil is supplied from the hydraulic pump to the pressure increaser. The supply channel may be shut off by the on-off valve when filling. In addition, a control valve for controlling the hydraulic oil supplied from the pressure intensifier to the actuator side is disposed on the actuator side of the supply channel from the on-off valve, and the supply channel is shut off by the control valve. At the same time, the timer means may measure the time for filling the pressure intensifier from the hydraulic pump in a state where the supply flow path is communicated with the on-off valve.

As described in detail above, the invention according to claim 1 measures the time for filling the hydraulic oil from the hydraulic pump to the pressure intensifier with the timer means, and issues an alarm when the time measured by the timer means exceeds the set time. To emit. For this reason, the operator can recognize that the leakage of hydraulic oil from the hydraulic pump is increasing from the normal value because the time required to fill the pressure booster from the hydraulic pump exceeds the set time. It is possible to detect in advance the life of a hydraulic pump that fills the pressure intensifier with hydraulic oil.
Note that the set time is a time required for filling the pressure intensifier with hydraulic oil that is a normal hydraulic pump and has the lowest performance within an allowable range due to machine differences.

  In addition to the effect of the invention of claim 1, the invention of claim 2 is filled with hydraulic oil from the hydraulic pump to the pressure intensifier, and the piston of the pressure intensifier has a minimum amount of hydraulic oil filled. Since the time for moving from the first position to the second position where the amount of hydraulic oil filled is in the maximum state is measured, the first position and the second position may be the start and end of the piston movement, respectively. And the positions of the first position and the second position can be easily set.

  According to a third aspect of the present invention, in addition to the effects of the first and second aspects of the present invention, an on-off valve that communicates and shuts off the supply flow path that connects the pressure intensifier and the actuator side is provided in the supply flow path. Since the supply flow path is shut off by the on-off valve when the hydraulic oil is filled from the hydraulic pump to the pressure booster, the hydraulic oil filling the pressure booster from the hydraulic pump can be well prevented from leaking to the actuator side, This is possible without erroneously detecting the end of the life of the hydraulic pump based on the leakage of hydraulic oil from the hydraulic pump.

In addition to the effect of the invention described in claim 3, the invention described in claim 4 shuts off the supply flow path with a control valve disposed closer to the actuator than the open / close valve of the supply flow path, With the supply channel in communication, the time for filling the pressure booster from the hydraulic pump to the hydraulic oil is measured by the timer means, and when this measured time exceeds the set time, hydraulic oil leakage from the control valve is normal. It can be detected that the value is increasing from the value, and the arrival of the life of the control valve can also be detected in advance.
Note that the set time is a normal control valve that has the largest leakage amount in the shut-off state within an allowable range due to machine differences, is arranged in the supply flow path, and the hydraulic oil is filled from the normal hydraulic pump to the pressure intensifier. It takes time to complete.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In FIG. 1, 1 is a tank which stores hydraulic oil inside. Reference numeral 2 denotes a three-phase induction motor that drives the hydraulic pump 3 to rotate. The hydraulic pump 3 sucks and discharges the stored hydraulic oil in the tank 1 by rotational driving by the electric motor 2. Reference numeral 4 denotes a suction flow path of the hydraulic pump 3, whose tip is immersed in the storage hydraulic oil of the tank 1. Reference numeral 5 denotes a discharge passage through which hydraulic oil discharged from the hydraulic pump 3 flows, and is connected to a supply passage 8 that connects the pressure intensifier 6 and hydraulic cylinders 7A, 7B, and 7C as actuators. Reference numeral 9 denotes a return flow path for flowing hydraulic oil flowing back into the tank 1 from the hydraulic cylinders 7A, 7B, 7C.

  10 is a safety valve that sets an upper limit of the pressure of hydraulic oil discharged from the hydraulic pump 3. The safety valve 10 is disposed in a discharge flow path 11 that branches from the discharge flow path 5 and communicates with the tank 1, and is discharged from the hydraulic pump 3. When the pressure exceeds the set value, the opening operation is performed, and the hydraulic oil is returned to the inside of the tank 1. A pressure gauge 12 displays the pressure of hydraulic oil discharged from the hydraulic pump 3 and is branchedly connected to the discharge flow path 5. Reference numeral 13 denotes a check valve that prevents the reverse flow of hydraulic oil discharged from the hydraulic pump 3 and is disposed in the discharge flow path 5. 14 is an oil filler / air breather for the tank 1, and 15 is an oil level gauge that makes it possible to visually recognize the amount of stored hydraulic oil in the tank 1 from the outside.

  The pressure intensifier 6 is provided with a piston 16 movably inside, a large-diameter working chamber 17 for introducing compressed air, and a hydraulic oil having a smaller diameter than the working chamber 17 and connected to the supply flow path 8 and discharged from the hydraulic pump 3. The pressure ratio of the working chamber 17 and the pressure increasing chamber 18 is determined by the action of the acting force based on the pressure of the compressed air introduced into the working chamber 17 on the piston 16. Accordingly, the hydraulic oil filled in the pressure increasing chamber 18 is increased in pressure and supplied to the supply flow path 8. Reference numeral 20 denotes an atmospheric chamber, which is partitioned and formed opposite to the working chamber 17 via the piston 16, and is open to the atmosphere. The piston 16 is positioned at the upper first position L (shown in the right half of the piston 16 in FIG. 1) in the minimum state of the amount of hydraulic oil filled in the pressure increasing chamber 18, and the amount of hydraulic oil charged in the pressure increasing chamber 18 is reached. Is located at a lower second position H (shown in the left half of the piston 16 in FIG. 1). Reference numeral 19A denotes a first detection means comprising a proximity type position detection switch, which is attached to the upper portion of the pressure booster 6, and is an operating position where the piston 16 is below the first position L and the amount of hydraulic oil charged in the pressure increasing chamber 18 becomes small. A signal is emitted when positioned at M. Reference numeral 19B denotes second detection means including a proximity position detection switch, which is attached to the pressure intensifier 6 below the first detection means 19A, and generates a signal when the piston 16 is located at the second position H.

  Reference numeral 21 denotes an electromagnetically operated on-off valve disposed in the supply flow path 8, which cuts off the supply flow path 8 by energization / non-energization by electromagnetic operation. The on-off valve 21 is a no-leak type, and when supplying hydraulic oil from the hydraulic pump 3 to the pressure booster 6, the supply flow path 8 is shut off by energization, and the hydraulic oil from the pressure booster 6 to the hydraulic cylinders 7A, 7B, 7C side. When supplying the liquid, the supply flow path 8 is communicated by non-energization. An open valve 22 for electromagnetic operation is disposed in the connection flow path 23 that connects between the supply flow path 8 and the return flow path 9, and normally shuts off the connection flow path 23 by energization and turns off the entire power supply. The connection flow path 23 is communicated by non-energization at the time of failure or emergency stop. 24A, 24B and 24C are electromagnetic switching valves as control valves for controlling the hydraulic oil supplied from the pressure intensifier 6 to the hydraulic cylinders 7A, 7B and 7C. From the location of the on-off valve 21 in the supply flow path 8, the hydraulic cylinders 7A, 7B, and 7C are arranged in branch supply channels 8A, 8B, and 8C that branch to the supply channel 8 on the side. The electromagnetic switching valves 24A, 24B, and 24C are three-position four-port valves that include two solenoids, and a first switching position that supplies hydraulic oil to the cap side of the hydraulic cylinders 7A, 7B, and 7C by energizing one of the solenoids. X, a second switching position Y for supplying hydraulic oil to the head side of the hydraulic cylinders 7A, 7B, 7C by energizing the other solenoid, and branch supply channels 8A, 8B, 8C by de-energizing both solenoids And a neutral position Z for blocking. 9A, 9B, and 9C are branch return flow paths that branch to the return flow path 9, and hydraulic oil from the hydraulic cylinders 7A, 7B, and 7C flows through the electromagnetic switching valves 24A, 24B, and 24C.

  As shown in FIG. 2, the electric motor 2 and the power source 25 are electrically connected by electric wirings 26, 27, and 28, and magnetic contacts 29, 30, and 31 are arranged on the electric wirings 26, 27, and 28. When the contacts 29, 30, 31 are closed, the electric motor 2 is energized to rotationally drive the hydraulic pump 3, and when the magnet contacts 29, 30, 31 are opened, the electric motor 2 is de-energized to stop the hydraulic pump 3.

  As shown in FIG. 3, an operation preparation contact 32 and a relay 33 that are closed when an operation preparation signal is input from an external control device (not shown) are connected in series, and a timer 34 is arranged in parallel with the relay 33. The relay 33 operates by closing the operation preparation contact 32 and closes the relay contact 33A. When the operation preparation contact 32 is closed, the timer 34 opens the timer contact 34A after a short set time has elapsed, and energizes a magnet switch 37, which will be described in detail later, only when an operation preparation signal is received. The first relay 35 is connected in series with the first detection means 19A, and the first relay 35 is activated when the first detection means 19A is closed (sends a signal) to close the first relay contact 35A. The second relay 36 is connected in series with the second detection means 19B, and the second relay 36 is activated by closing (sending a signal) the second detection means 19B to open the normally closed second relay contact 36A. . A first relay contact 35A, a second relay contact 36A, and a magnet switch 37 are connected in series. The magnet switch 37 closes the magnet contacts 38 and 39 and the magnet contacts 29, 30, and 31 shown in FIG. The magnet contacts 38, 39, 29, 30, 31 are opened by energization. The relay contact 33A and the timer contact 34A are connected in series, and these are arranged in parallel with the first relay contact 35A. The magnet contact 38 is disposed in parallel with the relay contact 33A, the timer contact 34A, and the first relay contact 35A connected in series, and functions to self-hold the energization of the magnet switch 37. The magnet contact 39 is connected in series with the timer means 40. The timer means 40 starts measuring time by closing the magnet contact 39, and closes the timer contact 40A when the measured time exceeds the set time. A timer contact 40A and a lamp 41 as an alarm means are connected in series, and the lamp 41 is turned on when the timer contact 40A is closed. The set time is a normal hydraulic pump and the one with the lowest performance within an allowable range due to machine difference fills the pressure increasing chamber 18 of the pressure booster 6 with hydraulic oil, and the piston 16 moves from the first position L to the second position H. It takes time to move to.

Next, the operation of this configuration will be described.
In the state of FIG. 1, when the on-off valve 21 and the open valve 22 are energized to cut off the supply flow path 8 and the connection flow path 23 and the hydraulic pump 3 is driven to rotate by the electric motor 2, the hydraulic pump 3 is removed from the suction flow path 4. The hydraulic oil stored in the tank 1 is sucked and discharged to the discharge flow path 5, and the hydraulic oil flows through the supply flow path 8 from the discharge flow path 5 and is filled in the pressure increasing chamber 18 of the pressure booster 6. The piston 16 moves downward against the action force based on the pressure of the compressed air introduced into the action chamber 17 by the action force based on the pressure of the hydraulic oil filled in the pressure increasing chamber 18, and is shown in the left half of FIG. When moving to the second position H, the second detection means 19B generates a signal and stops the electric motor 2.

  In this state, when the on-off valve 21 is de-energized, the supply flow path 8 is communicated, and the electromagnetic switching valves 24A, 24B, 24C at the neutral position Z are energized and switched to the first switching position X, the pressure booster 6 The piston 16 is moved upward by an acting force based on the pressure of the compressed air introduced into the working chamber 17, and the hydraulic oil filled in the pressure increasing chamber 18 is increased based on the area ratio between the working chamber 17 and the pressure increasing chamber 18. Press to discharge. The discharged hydraulic oil is blocked from flowing to the pump 3 side by the check valve 13 and flows from the supply flow path 8 to the on-off valve 21 and the branch supply flow paths 8A, 8B, 8C to the hydraulic cylinders 7A, 7B, The hydraulic cylinders 7A, 7B, and 7C are supplied to the cap side of 7C and operate in the right direction in FIG. 1, and the hydraulic oil from the head side flows through the return flow paths 9 from the branch return flow paths 9A, 9B, and 9C. Then, it is refluxed into the tank 1.

  When each of the hydraulic cylinders 7A, 7B, 7C is operated in the right direction in FIG. 1 and the electromagnetic switching valves 24A, 24B, 24C are deenergized and switched to the neutral position Z, the hydraulic cylinders 7A, 7B, 7C are Stop in the right direction of FIG. In this state, when each electromagnetic switching valve 24A, 24B, 24C is energized and switched to the second switching position Y, the hydraulic fluid flowing from the pressure intensifier 6 through the supply flow path 8 is on the head side of each hydraulic cylinder 7A, 7B, 7C. The hydraulic cylinders 7A, 7B, and 7C are operated in the left direction in FIG. 1, and hydraulic oil from the cap side flows through the return flow path 9 and is returned to the inside of the tank 1. When the hydraulic cylinders 7A, 7B, and 7C return to the state shown in FIG. 1, the electromagnetic switching valves 24A, 24B, and 24C are deenergized and switched to the neutral position Z, and the hydraulic cylinders 7A, 7B, and 7C are stopped. . Each of the hydraulic cylinders 7A, 7B, and 7C is operated at the same time as described above. In addition, any two of the three electromagnetic switching valves 24A, 24B, and 24C can be switched or any one can be selected. By switching these, two hydraulic cylinders 7A, 7B or 7A, 7C or 7B, 7C can be operated simultaneously, or one hydraulic cylinder 7A, 7B or 7C can be operated.

  When the operations by the hydraulic cylinders 7A, 7B, and 7C are completed, and the amount of hydraulic oil is reduced due to the consumption of the hydraulic oil filled in the pressure increasing chamber 18, the first detection means 19A outputs a signal when the piston 16 reaches the operating position M. , The electric motor 2 is rotated again, and the hydraulic oil discharged from the hydraulic pump 3 is filled in the pressure increasing chamber 18. When the pressure increase chamber 18 is filled with the hydraulic oil by this filling and the piston 16 reaches the second position H, the electric motor 3 is stopped.

  When the hydraulic cylinders 7A, 7B, 7C are stopped for a long time, such as when the hydraulic cylinders 7A, 7B, 7C are stopped until the next work is started, the on-off valve 21 is energized. Then, the supply flow path 8 is shut off, and leakage of the hydraulic oil filled in the pressure increasing chamber 18 is prevented.

  In addition, when the apparatus that has completed the work for one day is stopped, the electric motor 2 is stopped, and the opening / closing valve 21, the opening valve 22, and the electromagnetic switching valves 24A, 24B, 24C are de-energized to fill the pressure increasing chamber 18. The oil flows from the connection flow path 23 through the return flow path 9 and recirculates into the tank 1, and the piston 16 moves to the uppermost position by the action force based on the pressure of the compressed air introduced into the action chamber 17, and the right half of FIG. The first position L shown in FIG.

  When an operation preparation signal is input from an external control device at the start of a day's work, the operation preparation contact 32 is closed and the relay 33 is activated, and the timer 34 starts measuring time. At this time, the opening / closing valve 21 and the opening valve 23 are energized by the input of the operation preparation signal, and the supply flow path 8 and the connection flow path 23 are shut off. The relay 33 closes the relay contact 33A, the magnet switch 37 is energized, and the magnet contacts 29, 30, 31, 38, 39 are closed. Although the timer 34 opens the timer contact 34A after a short set time has elapsed, the magnet switch 37 is energized continuously by closing the magnet contact 38. The electric motor 2 is energized when the magnet contacts 29, 30, 31 are closed to rotate the hydraulic pump 3, fill the pressure increasing chamber 18 with hydraulic oil, and the piston 16 moves downward from the first position L. At the same time, the timer means 40 starts measuring time by closing the magnet contact 39, and closes the timer contact 40A after the set time has elapsed.

  When the piston 16 moving downward from the first position L reaches the second position H by filling the pressure increasing chamber 18 with the hydraulic oil, the second detection means 19B is closed and the second relay 36 is operated, 2 relay 36 opens the normally closed second relay contact 36A. As a result, the magnet switch 37 is de-energized and opens the magnet contacts 29, 30, 31, 38, 39. The electric motor 2 is de-energized due to the opening of the magnet contacts 29, 30, 31 and stops the rotational drive of the hydraulic pump 3. The timer means 40 is deactivated by opening the magnet contact 39. Therefore, the time measured by the timer means 40, that is, the time required for the piston 16 to move from the first position L to the second position H by filling the hydraulic oil from the hydraulic pump 3 to the pressure increasing chamber 18 is within the set time. If there is, the magnet contact 39 is opened by the movement of the piston 16 to the second position H, the timer means 40 is deactivated, the timer contact 40A is open, and the lamp 41 is not lit. On the other hand, if the time required for the piston 18 to move from the first position L to the second position H by filling the hydraulic oil from the hydraulic pump 3 to the pressure increasing chamber 18 exceeds the set time, the piston 18 is moved to the second position H. The timer contact 40A is closed and the lamp 41 is lit before the magnet contact 39 is opened.

  For this reason, the hydraulic oil is filled in the pressure increasing chamber 18 of the pressure booster 6 from the hydraulic pump 3 and the time required for the piston 16 to move from the first position L to the second position H exceeds the set time. The operator can recognize from the warning that the lamp 41 is lit that the leakage of hydraulic oil from the pump 3 is increasing from the normal value, and the life of the hydraulic pump 3 that fills the pressure intensifier 6 is detected in advance. can do.

  In addition, when the hydraulic oil is charged from the hydraulic pump 3 to the pressure intensifier 6, the piston 16 is filled with the hydraulic oil amount from the first position L where the charged hydraulic oil amount is in the minimum state. Since the time to move to the first position L and the second position H is measured, the first position L and the second position H can be set as the start end and the end position, respectively, and the positions of the first position L and the second position H are easy. Can be set to

  Further, an open / close valve 21 for communicating and disconnecting the supply flow path 8 connecting the pressure intensifier 6 and the hydraulic cylinders 7A, 7B, and 7C is provided in the supply flow path 8, and hydraulic oil is supplied from the hydraulic pump 3 to the pressure increaser 6. Since the supply flow path 8 is shut off by the on-off valve 21 when filling, the hydraulic oil filling the pressure booster 6 from the hydraulic pump 3 can be well prevented from leaking to the hydraulic cylinders 7A, 7B, 7C side. This is possible without erroneously detecting the end of the service life of the hydraulic pump 3 due to the leakage of hydraulic oil from the hydraulic pump.

  Further, the branching supply flow path branchingly connected to the supply flow path 8 by switching the electromagnetic switching valves 24A, 24B, 24C disposed on the hydraulic cylinders 7A, 7B, 7C side from the on-off valve 21 of the supply flow path 8 to the neutral position Z. 8A, 8B and 8C are shut off, and the timer means 40 measures the time for filling the pressure increasing chamber 18 of the pressure booster 6 from the hydraulic pump 3 while the supply flow path 8 is communicated by the on-off valve 21. When the measured time exceeds the set time, it can be detected that the sum of the leakage amount of hydraulic oil at the neutral position Z of the three electromagnetic switching valves 24A, 24B, 24C is increasing from the normal value. The arrival of the life of the switching valves 24A, 24B, 24C can also be detected in advance. It should be noted that the set time is three normal solenoid switching valves with the largest leakage amount within the allowable range due to machine differences, and are arranged in the branch supply flow paths 8A, 8B, 8C. The time required for the piston 16 to move from the first position to the second position by filling the pressure-increasing chamber 18 of the pressure device 6 with hydraulic oil is used.

  In the embodiment, the three hydraulic cylinders 7A, 7B, and 7C are provided as actuators. However, the present invention is not limited to this, and it goes without saying that the number can be set according to the application. Of course, a hydraulic motor may be used instead of the hydraulic cylinders 7A, 7B, and 7C. Further, when the time measured by the timer means 40 exceeds the set time, the lamp 41 is turned on and an alarm is issued, but it is needless to say that an alarm may be issued with a sound such as a buzzer.

1 is a hydraulic circuit diagram of a hydraulic apparatus showing an embodiment of the present invention. It is the motive power circuit diagram which showed the connection of the power supply and electric motor of one Embodiment. It is a control circuit diagram of one embodiment.

Explanation of symbols

3: Hydraulic pump 6: Booster 7A, 7B, 7C: Hydraulic cylinder (actuator)
8: Supply flow path 16: Piston 21: On-off valve 40: Timer means 24A, 24B, 24C: Electromagnetic switching valve (control valve)
L: 1st position H: 2nd position

Claims (4)

  A hydraulic pump that sucks and discharges hydraulic oil and a pressure booster that fills the hydraulic oil discharged from the hydraulic pump and supplies the filled hydraulic oil to the actuator side are filled with hydraulic oil from the hydraulic pump to the pressure booster A hydraulic device characterized by comprising a timer means for measuring a time to perform, and issuing an alarm when the time measured by the timer means exceeds a set time.   The pressure intensifier is provided with a piston for increasing the operating reason charged from the hydraulic pump and supplying it to the actuator side so that the piston can move inward. In addition, the timer is positioned at the second position with the maximum amount of hydraulic oil filled, and the timer means is moved from the first position to the second position by charging the hydraulic oil from the hydraulic pump to the pressure intensifier. The hydraulic apparatus according to claim 1, wherein a time for performing the measurement is measured.   A supply flow path for connecting the pressure intensifier and the actuator side is provided, and an on-off valve for communicating and blocking the supply flow path is provided in the supply flow path, and the hydraulic oil is filled into the pressure intensifier from the hydraulic pump. 3. The hydraulic device according to claim 1, wherein the supply passage is shut off by the on-off valve.   A control valve for controlling hydraulic fluid supplied from the pressure intensifier to the actuator side is disposed on the actuator side of the supply passage from the on-off valve, and the supply passage is shut off by the control valve. 4. The hydraulic device according to claim 3, wherein the timer unit measures a time for filling the pressure booster from the hydraulic pump in a state where the supply flow path is communicated with the opening / closing valve.

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