JP2002181006A - Hydraulic actuator controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic actuator controller capable of controlling a return liquid amount in a return liquid pipe lens in a pressure reducing process further accurately and having excellent practicality. SOLUTION: This hydraulic actuator controller controls increase or decrease of pressure of a hydraulic actuator 1 by a supply liquid amount in a supply liquid pipe line 2 or a return liquid amount in the return liquid pipe line 3. An opening/closing valve 7 for reducing pressure opened when a pressure in the return liquid pipe line 3 exceeds a predetermined pressure through a discharge amount variable pump 6 for return liquid is provided in the return liquid pipe line 3, and a supply mechanism 9 for supplying liquid is provided between the discharge amount variable pump 6 for return liquid and the opening/closing valve 7 for reducing pressure in the return liquid pipe line 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic actuator control device.

[0002]

2. Description of the Related Art In recent years,
In high-pressure presses aimed at synthesizing new substances under ultra-high pressure and measuring material properties, which are fields of interest, at least 2-50M
Some are N or more.

One example of this application is a high-pressure vessel or a high-hydraulic cylinder with a hydraulic pressure of 70 MPa or more. A long-term pressurizing / depressurizing program control of the high-pressure vessel or the high-hydraulic cylinder has been performed with the recent development of automatic measuring equipment. Demand growth is growing.

In this type of control, high pressure or flow control in proportion to the control voltage can be achieved by simply increasing the pressure by changing the operation of the constant discharge hydraulic pump from an induction motor to an inverter motor.

On the other hand, the pressure reduction is usually performed by a control valve, and unlike the pump, the operating force may be small, but the pressure on the inflow side affects the flow rate through the control valve. Therefore, in order to realize precise high-pressure control, there is a demand for a device having a flow rate characteristic independent of pressure, unlike a conventional control valve.

The present inventors have proposed Japanese Patent Laid-Open No. Hei 10-267006 in order to achieve this demand.

Japanese Patent Application Laid-Open No. Hei 10-267006 discloses a technique in which pressure increase or pressure reduction control of a hydraulic actuator is controlled by a liquid supply amount in a liquid supply line or a liquid return amount in a return liquid line. The liquid line is provided with a pressure increasing check valve which opens when the pressure of the liquid supply line becomes equal to or higher than a predetermined pressure via a liquid discharge amount variable pump, and the return liquid line is provided in the return liquid line. A pressure-reducing check valve is provided which opens when the return liquid line becomes equal to or higher than a predetermined pressure via a variable amount pump, and the pressure of the return liquid line is controlled by controlling the discharge amount of the return liquid discharge amount variable pump. , And the pressure in the return liquid line that has been pressurized opens the pressure-reducing check valve to discharge the liquid in the return liquid line.

If the pressure of the return liquid line is not increased by the return liquid discharge amount variable pump (for example, if nothing is done), the pressure of the hydraulic actuator acts on the pressure reducing check valve as it is, The return liquid cannot be controlled.

However, since the pressure reducing check valve is configured to be opened and closed by the pressure of the return liquid line as described above,
For example, as shown in FIG. 1, a branch line 10 branched from the return line 3a upstream of the variable return amount pump is provided, and the branch line 10 and the variable return amount discharge pump are provided. The pressure between the return line 3b and the return line 3b downstream of the pump is constantly urged toward the return line 3b by the pressure of the branch line 10 and the urging of the urging mechanism 11 (a spring body in the drawing). A valve body 12 is provided, and the valve body 12 is provided on the side of the branch line 10 against the pressure of the branch line 10 and the urging of the urging mechanism 11 due to an increase in the pressure of the return liquid line 3b. Return line 3 downstream of the valve body 12
In the case of the pressure-reducing check valve 7 configured to open the valve c (the same components as those in the embodiment are denoted by the same reference numerals), the valve body 12 may be worn due to aging, or the urging mechanism 11 may be used. Therefore, there is a problem that a larger amount of liquid flows out than expected outflow characteristics, and a liquid flows out even at the predetermined pressure or less.

Furthermore, even if the valve element 12 has not deteriorated over time, if the pressure of the hydraulic actuator is reduced at an extremely low speed, the valve opening / closing sensitivity of the valve element 12 is likely to be insufficient. There is also a problem that the liquid may pass through.

Further, such a valve that opens and closes at a predetermined pressure has a large variation in pressure when the valve opens and closes (spray stop phenomenon), and it cannot be said that the control of the pressure or the flow rate with high precision is insufficient. Not get.

The present invention solves the above problems,
An object of the present invention is to provide a hydraulic actuator control device which is excellent in practicality and can more accurately control the amount of liquid returned in a return liquid line in a pressure reducing process.

[0013]

The gist of the present invention will be described with reference to the accompanying drawings.

The control of increasing or decreasing the pressure of the hydraulic actuator 1 is performed by controlling the supply amount of liquid in the supply line 2 or the return line 3.
A hydraulic actuator control device that controls the amount of return liquid in the return liquid line, wherein the pressure in the return liquid line 3 is equal to or higher than a predetermined pressure via a return liquid discharge amount variable pump 6. And a supply mechanism 9 for supplying liquid between the return liquid discharge amount variable pump 6 and the pressure reducing on-off valve 7 as the return liquid line 3. The present invention relates to a hydraulic actuator control device characterized in that:

Further, in the hydraulic actuator control device according to claim 1, a return liquid pipe for detecting the pressure between the return liquid discharge amount variable pump 6 and the pressure reducing on-off valve 7 as the return liquid pipe line 3. When the pressure detected by the return liquid line pressure detecting device 15 is lower than the set pressure, the supply mechanism 9 sets the return liquid line 3 to the return liquid discharge amount variable pump 6. The present invention relates to a hydraulic actuator control device characterized in that a liquid is supplied between the pressure reducing on-off valve 7.

Further, in the hydraulic actuator control device according to any one of claims 1 and 2, the supply mechanism 9 includes:
The present invention relates to a hydraulic actuator control device, which is connected to a liquid supply pipe 2 by a communication passage 8.

Further, in the hydraulic actuator control device according to the third aspect, the supply line 2 is provided with an opening / closing valve 5 for boosting the pressure through a variable discharge pump 4 for the liquid supply, and the communication path 8 is connected to the liquid supply line. A position connected to the pipe line 2 is related to a hydraulic actuator control device, wherein the position is set between the liquid supply variable discharge pump 4 and the pressure increasing on-off valve 5.

Further, in the hydraulic actuator control device according to the fourth aspect, the communication passage 8 is provided with a communication passage opening / closing valve 14, and the pressure increasing opening / closing valve 5 is closed and the communication passage opening / closing valve 14 is opened. The actuator control device is characterized in that a supply mechanism 9 configured to supply the liquid from the liquid supply line 2 to the return liquid line 3 by operating the liquid supply discharge amount variable pump 4 is adopted. It is related.

Further, in the hydraulic actuator control device according to any one of claims 1 to 5, the pressure reducing on-off valve 7
A branch line 10 branched from the return line 3 on the more upstream side is provided. Between the branch line 10 and the return line 3, the pressure of the branch line 10 and an appropriate A valve body 12 constantly urged toward the return liquid line 3 by the urging of the urging mechanism 11 is provided,
A pressure-reducing opening / closing device configured to open the return liquid line 3 when the valve body 12 moves toward the branch line 10 against the pressure of the branch line 10 and the urging of the urging mechanism 11. The present invention relates to a hydraulic actuator control device in which a valve 7 is employed.

Further, in the hydraulic actuator control device according to any one of claims 1 to 6, a liquid container 13 for storing liquid is provided between the return liquid variable discharge pump 6 and the pressure reducing on-off valve 7. The present invention relates to a hydraulic actuator control device characterized in that:

[0021]

When the amount of liquid flowing out of the pressure reducing on-off valve 7 which opens when the pressure of the return liquid line 3 becomes equal to or higher than a predetermined pressure is larger than a set amount, the larger amount of liquid is supplied from the supply mechanism 9. By refilling the return liquid line 3, the liquid in the return liquid line 3 becomes a predetermined amount, and the outflow amount from the hydraulic actuator 1 can be set to a predetermined amount.

Since the present embodiment is configured as described above, it is possible to control the pressure reduction of the hydraulic actuator very accurately by supplementing the amount of liquid returned during the pressure reduction process.

[0023]

BRIEF DESCRIPTION OF THE DRAWINGS The drawings illustrate one embodiment of the present invention and will be described below.

The present embodiment is a hydraulic actuator control device for controlling the pressure increase or reduction of the pressure of the hydraulic actuator 1 based on the amount of liquid supplied in the liquid supply line 2 or the amount of liquid returned in the return liquid line 3. The return line 3 is provided with a pressure-reducing on-off valve 7 that opens when the pressure of the return line 3 becomes equal to or higher than a predetermined pressure via a return amount variable discharge pump 6. A supply mechanism 9 for supplying liquid between the return liquid discharge amount variable pump 6 and the pressure reducing on-off valve 7 is provided in the return liquid conduit 3.

The liquid supply line 2 has a variable discharge pump 4 for liquid supply.
Is provided with an on-off valve 5 for boosting. In addition, the liquid supply line 2 increases the pressure of the liquid supply line 2 by operating the liquid supply discharge amount variable pump 4 and increasing the pressure of the liquid pressure actuator 1 by opening the pressure increasing on-off valve 5. It is configured so as to be able to exercise.

A safety valve 16 is disposed in the liquid supply line 2 between the hydraulic pressure actuator 1 and the liquid supply variable discharge pump 4, and a pressure abnormality or the like occurs in the liquid supply line 2 and pressure adjustment is required. In such a case, the liquid can be returned from the safety valve 16 to the tank 17.

The pressure reducing on-off valve 7 provided in the return liquid line 3
Employs a proportional pressure control valve called a so-called offset relief valve.

The proportional pressure control valve will be described in detail with reference to FIG. 1. A branch line 10 is provided which is branched from a return line 3a upstream of the variable return pump 6 for return. The pressure of the branch line 10 and the urging of the urging mechanism 11 (in the drawing, a spring body) are constantly provided between the line 10 and the return line 3b downstream of the return liquid variable discharge pump 6. Return liquid line 3
A configuration in which a valve element 12 urged toward the b side is provided is adopted, and the valve element 12 causes the pressure of the return liquid line 3b to rise due to the operation of the return liquid discharge amount variable pump 6, thereby increasing the pressure. Branch line
When moving toward the branch pipe 10 against the pressure of 10 and the urging of the urging mechanism 11, the return liquid pipe 3c downstream of the valve body 12 is opened.

The return liquid variable discharge pump 6 increases the pressure of the return liquid line 3b communicating with the pressure reducing on-off valve 7 by discharging liquid from the return liquid variable discharge pump 6, thereby increasing the pressure of the valve. The body 12 is configured to move to the branch conduit 10 side.

For example, as the pressure reducing on-off valve 7, a pressure control valve called a so-called relief valve for urging the valve body to the return liquid line upstream of the valve body only by the spring body is used. May be.

A safety valve 18 is provided in the return line 3b between the return amount variable discharge pump 6 and the pressure reducing on-off valve 7.
The liquid is returned from the safety valve 18 to the tank 19 when pressure abnormality or the like occurs in the return liquid pipe 3b and pressure adjustment is required.

The supply mechanism 9 is provided with a communication passage 8 for communicating the liquid supply line 2 with the return liquid line 3b, and the supply line 2 is connected to the return liquid line 3b via the communication path 8. Is adopted.

The upstream side of the communication passage 8 is formed as a liquid supply pipe 2 and is communicated between the liquid supply variable discharge pump 4 and the pressure increasing on-off valve 5. The communication passage 8 is provided with a communication passage opening / closing valve 14. Accordingly, when the variable discharge pump 4 for supplying liquid is operated in a state where the on-off valve 5 for boosting is closed and the on-off valve 14 for communication is opened, the liquid discharged by the variable pump 4 for supplying liquid is discharged. Is a hydraulic actuator 1
From the supply line 2 to the return line 3 via the communication passage opening / closing valve 14 and the communication passage 8 between the return liquid discharge amount variable pump 6 and the pressure reducing opening / closing valve 7. (Return liquid line 3
b).

A liquid container for storing the liquid and storing the pressure of the liquid between the return liquid discharge amount variable pump 6 and the pressure reducing on-off valve 7 (return liquid line 3b). 13 are provided. The working oil has a compression ratio of 4 to 5% (volume) at 70 MPa.

The liquid container 13 has a structure in which the liquid is simply stored therein, or, for example, as shown in FIG. 5, has a partition member 21 urged by an elastic body 20 such as a spring therein. A structure in which the liquid 23 inside is compressed by the bias of the elastic body 20 is employed.

The liquid container 13 is mainly provided with the return liquid line 3b.
It is used when the volume of is small.

In the control of supplying the liquid between the return liquid discharge amount variable pump 6 and the pressure reducing on-off valve 7 (return liquid line 3b) through the return liquid line 3, the liquid supply discharge amount variable pump 4, The operation of the pressure increasing on-off valve 5 and the communication path on-off valve 14 is performed by the first sensor 24 provided in the return liquid line 3 a upstream of the return liquid discharge amount variable pump 6 and the return liquid discharge amount variable pump 6. The second sensor 15 (return liquid line pressure detecting device described in the claims) provided in the return liquid line 3b between the pressure reducing on-off valve 7 and the first sensor 24 and the second sensor 15 are connected. Controller 26.

The controller 26 compares the input signal E (detected pressure) from the first sensor 24 with the input signal F (detected pressure) from the second sensor 15 and determines that the detected pressure of the second sensor 15 is appropriate. If the value is a value, the supply mechanism 9 is not operated and the output signal C closes the on-off valve 5 for pressure and the output signal B activates the variable discharge pump 6 for return liquid according to a predetermined return program. (See FIG. 4).

The pressure detected by the second sensor 15 is
If the value is improper due to deterioration or the like, that is, if the value is lower than the proper value (position P in FIG. 7), the supply amount variable pump 4 is controlled by the output signal A from the controller 26. At the same time, the communication passage opening / closing valve 14 is opened by the output signal D (in this state, the pressure increasing opening / closing valve 5 is kept closed), and the return liquid through the liquid supply line 2 and the communication passage 8 is returned. Liquid is supplied to the return liquid conduit 3b between the variable discharge rate pump 6 and the pressure reducing on-off valve 7 (see FIG. 5).

When the pressure detected by the second sensor 15 returns to an appropriate value due to the supply of the liquid from the communication passage 8 (position Q in FIG. 7), the discharge amount for liquid supply is determined by the output signal A from the controller 26. The operation of the variable pump 4 is stopped, and the communication path on-off valve 14 is closed by the output signal D.

In FIG. 7, the vertical axis represents pressure, the horizontal axis represents time, a graph denoted by V is a pressure transition graph of the hydraulic actuator 1, and a graph denoted by W is the return liquid discharge amount. It is a pressure transition graph of the return liquid pipeline 3b between the variable pump 6 and the on-off valve 7 for pressure reduction.

Since the present embodiment is constructed as described above, the amount of liquid flowing out of the pressure reducing on-off valve 7 which opens when the pressure of the return liquid line 3b becomes equal to or higher than a predetermined pressure is larger than a set amount, and When the pressure of the pipe 3b becomes lower than the control value, the excess liquid that has flowed out can be replenished from the supply mechanism 9 to the return liquid pipe 3b, and therefore, the return liquid variable discharge pump 6
It is possible to prevent the liquid in the return liquid pipe 3b between the pressure control valve 7 and the pressure reducing on-off valve 7 from decreasing faster than the control, thereby achieving accurate control of the return liquid amount, ie, accurate pressure reduction control of the hydraulic actuator 1. It becomes a hydraulic actuator control device with excellent practicality.

Since the pressure of the liquid sent to the pressure-reducing on-off valve 7 is controlled by the return liquid variable discharge pump 6, the amount of liquid supplied to the pressure-reducing on-off valve 7 can be appropriately controlled. Therefore, the flow amount of the liquid from the pressure reducing on-off valve 7 can be set to an appropriate set amount, and in this respect, accurate pressure reduction control can be achieved.

The supply mechanism 9 replenishes the liquid to the return line 3b only when the pressure in the return line 3b becomes lower than the control value. In this respect, accurate pressure reduction control can be achieved without increasing the pressure.

The liquid to be replenished by the supply mechanism 9 is
Since the liquid in the liquid supply line 2 originally supplied to the hydraulic actuator 1, the pressure characteristics and the like of the liquid to be replenished and the liquid existing in the return liquid line 3b are the same. No disadvantages such as pressure characteristics change occur,
Also in this respect, accurate pressure reduction control can be achieved.

Further, since the replenishment of the liquid by the supply mechanism 9 is performed by using the liquid supply discharge amount variable pump 4 used for increasing the pressure of the hydraulic actuator 1, the configuration of the entire apparatus is simplified as much as possible. In this respect, practicality is also excellent.

As the pressure reducing on-off valve 7, a valve body 12 for opening and closing the pressure reducing on-off valve 7 is branched from a return liquid line 3 a upstream of the return liquid discharge amount variable pump 6. Since the one that is urged toward the return liquid line 3b by the pressure of 10 is adopted, the movement of the valve element 12 is controlled by the pressure of the branch line 10 (that is, by the return liquid variable discharge pump 6). This is due to the difference between the pressure of the return liquid pipe 3a on the upstream side) and the pressure of the return liquid pipe 3b between the return liquid variable discharge pump 6 and the pressure reducing on-off valve 7. Good return control, that is, pressure reduction control, can be achieved in a wide range from high pressure to low pressure without depending on the level of the pressure of the return liquid line 3a upstream of the pump 6.

Further, in such a pressure reducing on-off valve 7, there is a problem of the change of the opening and closing characteristics due to the deterioration of the valve body 12 and the phenomenon of the stoppage of the jet (variation of the valve closing pressure). Due to the presence of the supply mechanism 9, the change in the opening / closing characteristics and the stoppage of the jetting phenomenon can be corrected. Therefore, also in this respect, good pressure reduction control can be achieved.

In particular, in an ultra-high pressure hydraulic actuator control device for the purpose of synthesizing a new substance under ultra-high pressure of 70 MPa or more and measuring the material properties, a shock is applied to the sample or the pressure inside the hydraulic actuator 1 is increased. Because the pressure is reduced slowly so that does not drop sharply locally,
Although the above-described stop-of-spring phenomenon was likely to occur, according to the present embodiment, good and accurate pressure reduction control can be performed by correcting the stop-of-spray phenomenon. Further, since the pressure inside the hydraulic actuator 1 is prevented from decreasing more than the control,
Also in this respect, it is excellent as an ultrahigh pressure hydraulic actuator control device.

The supply of the liquid to the return line 3b by the supply mechanism 9 is performed by inputting the signal E (detection pressure) from the first sensor 24.
And the input signal F (detected pressure) from the second sensor 15 is automatically compared by the controller 26, so that the return liquid pipe between the return liquid variable discharge pump 6 and the pressure reducing on-off valve 7 Road 3b
The abnormal pressure drop can be automatically and reliably corrected, and also in this respect, the hydraulic actuator control device is excellent.

Further, since the liquid container 13 is provided in the return line 3b between the return amount variable discharge pump 6 and the pressure reducing on-off valve 7, the pressure of the return line 3b is slightly reduced. If the pressure drops, the liquid stored in the liquid container 13 will be supplied. Therefore, if the pressure is small, the pressure drop can be corrected without operating the supply mechanism 9, and the communication path opening / closing valve 14
It also excels in practicality, such as the frequency of opening and closing of the can be reduced.

Further, the liquid supply discharge variable pump 4 disposed in the liquid supply line 2 is operated, and the pressure increasing / closing valve 5 is opened to feed the liquid to the liquid pressure actuator 1. The boosting can also be controlled and performed, and in this respect also, the practicality is excellent.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view showing a pressure-reducing on-off valve 7 of the present embodiment.

FIG. 2 is an explanatory diagram showing an outline of the present embodiment.

FIG. 3 is an explanatory diagram illustrating a return liquid state according to the present embodiment.

FIG. 4 is an explanatory diagram showing a liquid replenishment state by a supply mechanism 9 of the embodiment.

FIG. 5 is an explanatory diagram illustrating a control mechanism of the present embodiment.

FIG. 6 is an explanatory sectional view showing the liquid container 13 of the present embodiment.

FIG. 7 is an explanatory diagram illustrating a control graph according to the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic actuator 2 Supply liquid line 3 Return liquid line 4 Discharge rate variable pump for supply liquid 5 Boost opening / closing valve 6 Variable discharge amount pump for return liquid 7 Decompression on / off valve 8 Communication path 9 Supply mechanism 10 Branch line 11 Energizing mechanism 12 Valve element 13 Liquid container 14 Communication passage opening / closing valve 15 Return liquid line pressure detector

Claims (7)

[Claims] 1. A hydraulic actuator control device for controlling pressure increase or pressure reduction of a hydraulic actuator by a liquid supply amount in a liquid supply line or a liquid return amount in a return liquid line. The pipe is provided with a pressure reducing on-off valve that opens when the pressure of the return liquid pipe becomes equal to or higher than a predetermined pressure via a return liquid discharge amount variable pump. A hydraulic actuator control device, comprising: a supply mechanism for supplying a liquid between a discharge rate variable pump and the pressure reducing on-off valve. 2. The return hydraulic line pressure detecting device according to claim 1, wherein a return liquid line pressure is detected by detecting a pressure between the return liquid discharge amount variable pump and the pressure reducing on-off valve. When the pressure detected by the return line pressure sensor is lower than a set pressure, a supply mechanism is used as a return line between the return liquid discharge amount variable pump and the pressure reducing on-off valve. A hydraulic actuator control device configured to supply a liquid. 3. The hydraulic actuator control device according to claim 1, wherein the supply mechanism is communicated with the liquid supply pipe by a communication path. . 4. The hydraulic actuator control device according to claim 3, wherein the supply line is provided with an on-off valve for increasing pressure through a supply amount variable pump, and the communication path communicates with the supply line. The position to be set is set between the liquid supply variable discharge pump and the pressure increasing / closing valve. 5. The hydraulic actuator control device according to claim 4, wherein a communication passage opening / closing valve is provided in the communication passage, and the pressure supply opening / closing valve is closed and the liquid supply discharge is performed in a state where the communication passage opening / closing valve is opened. An actuator control device comprising a supply mechanism configured to supply liquid from a liquid supply line to a return liquid line by operating a variable volume pump. 6. The hydraulic actuator control device according to claim 1, further comprising: a branch pipe branched from a return liquid pipe upstream of the pressure reducing on-off valve.
A valve body which is constantly urged toward the return liquid line by the pressure of the branch line and the urging of an appropriate urging mechanism is provided between the branch line and the return liquid line. A pressure reducing on-off valve configured to open the return liquid line when the valve element moves toward the branch line side against the pressure of the branch line and the urging of the urging mechanism is adopted. A hydraulic actuator control device, characterized in that: 7. A hydraulic actuator control device according to claim 1, wherein a liquid container for storing liquid is provided between the return liquid discharge amount variable pump and the pressure reducing on-off valve. A hydraulic actuator control device, characterized in that: