JPH06202739A - Electrically controlled liquid pressure controller - Google Patents

Abstract

PURPOSE:To improve the linearity, the reproducibility, and the responsiveness to improve the control precision and to have no over-ride characteristics to prevent the occurrence of a high surge voltage. CONSTITUTION:The pilot pressure liquid of a pilot valve 3 whose spool 12 is displaced by an electromagnetic actuator 10 and a spring 11 resisting it is supplied to the pilot port of a main valve 2, which is provided with a pressure port Pm receiving the supply of pressured liquid from a liquid pressure generation source 1 and tank ports Tm1 and Tm2 returning it to a reservoir tank 7, to control the movement speed of a valve body 8. Therefore, an electric control part 6 generates an operation signal to the electromagnetic actuator 10 so that a pressure command signal Pc and a feedback signal Pf obtained by detecting the liquid pressure of the pressure port Pm by a pressure converter 5 coincide with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device for controlling the pressure of fluid such as hydraulic oil with high accuracy.

[0002]

2. Description of the Related Art In a conventional hydraulic pressure control device, for example, an electric control unit drives a torque motor to move a spool in accordance with a deviation between a pressure command signal and a detection signal of an output hydraulic pressure, and the above-mentioned output liquid pressure controller is operated. There is a servo valve that controls the pressure to the commanded pressure.

In such a servo valve, since the displacement of the valve body is proportional to the operation amount of the electric control unit, for example, if the supply flow rate of the hydraulic pressure source changes with respect to a certain pressure command, the valve body will change. Must be displaced to compensate for it, and the operation amount of the electric control unit must be changed to some extent. This is called the override characteristic.

[0004]

SUMMARY OF THE INVENTION In order to eliminate this,
There is a problem in that the electric control section needs an integral compensation element, which slows the response speed. Not only that, when the hydraulic pressure in the pipeline having the pressure transducer (pressure sensor) decreases with respect to the pressure command due to the operation of the actuator connected to the control port, the integrator of the electric control unit is saturated. At this time, the hydraulic pressure in the pipeline increases due to the stop of the actuator, etc., and even when the pressure command value is reached, the hydraulic pressure further increases due to the saturation of the integrator, which may cause a high surge pressure. It was

The present invention has been made in view of the above points, and does not have the above-mentioned override characteristic, and the deviation between the pressure command and the detected pressure can be made very small, and the electric control system excellent in linearity and reproducibility can be obtained. An object is to provide a hydraulic control device. It is also an object to prevent generation of high surge pressure.

[0006]

In order to achieve the above object, the present invention provides an electrically controlled hydraulic pressure control device comprising the following (A) to (D).

(A) A pressure port supplied with a pressure fluid from a fluid pressure generation source and a tank port for returning the fluid to a reservoir tank are provided, and the pressure of the pressure port is mainly controlled according to the displacement of the built-in valve body. The valve, (B) the spool is displaced by an electromagnetic actuator that generates thrust corresponding to an electric signal and a spring that opposes the thrust, and the displacement is determined by the thrust of the electromagnetic actuator, and pilot pressure fluid is supplied to the main valve. A pilot valve for controlling the moving speed of the valve body, (C) a pressure converter for detecting the pressure in the pressure liquid supply pipeline from the hydraulic pressure source to the pressure port of the main valve, and generating an electric signal, D) The command signal of pressure and the electric signal from the pressure converter are received, and the electromagnetic actuator of the pilot valve is operated so that both signal values are matched. Electric control unit for generating a signal,

In this electrically controlled hydraulic pressure control device, the pilot valve is a three-way valve, and the main valve applies the hydraulic pressure supplied from the hydraulic pressure source to one end of its valve body, while It is advisable to apply the hydraulic pressure of the control port of the pilot three-way valve to the end portion. Alternatively, the pilot valve may be a four-way valve, and the main valve may apply the hydraulic pressures of the first and second control ports of the pilot four-way valve to both ends of the valve body.

The present invention also provides an electrically controlled hydraulic pressure control device comprising the following (a) to (d). (A) A pressure port that receives supply of a pressure fluid from a fluid pressure generation source, a tank port that recirculates to a reservoir tank, and a control port that is provided between the pressure port and the tank port and that responds to the displacement of a built-in valve element. The spool is displaced by a main valve that controls the port pressure, (b) an electromagnetic actuator that generates thrust according to an electric signal, and a spring that opposes the thrust, and the displacement is determined by the thrust of the electromagnetic actuator. A pilot valve that supplies pilot pressure fluid to control the moving speed of the valve body,
(C) A pressure converter that detects the pressure liquid at the control port of the main valve to generate an electric signal, and (d) receives a command signal of the pressure and the electric signal from the pressure converter, and matches both signal values. An electric control unit for generating an operation signal to the electromagnetic actuator of the pilot valve,

In this electrically controlled hydraulic pressure control device, the pilot valve is a three-way valve, and the main valve causes the hydraulic pressure of the control port of the pilot three-way valve to act on one end of the valve body and the other end. A biasing force of a spring may be applied to the end of the. Alternatively, set the pilot valve to 4
The main valve may be a one-way valve, and the main valve may exert hydraulic pressure on the first and second control ports of the pilot four-way valve on both ends of the main spool.

Further, in these electrically controlled hydraulic pressure control devices, it is desirable that the electrical control section is provided with a proportional compensation element or a proportional compensation element and a differential compensation element. Further, the electric control unit may be provided with means for changing the compensation constant according to the value of the electric signal from the pressure converter. Alternatively, the electric control section may include a proportional compensation element, a differential compensation element, and a second derivative compensation element.

[0012]

In each of the electric control type hydraulic pressure control devices according to the present invention constructed as described above, the electromagnetic actuator displaces its spool by the operation amount from the electric control section to the pilot valve, and the pilot liquid is flowed at a flow rate substantially proportional thereto. Flow into or out of the control port. That is, the operation amount to the pilot valve controls the displacement speed of the valve body of the main valve. When the valve body of the main valve controlled in this way is settled at a certain position regardless of its displacement amount, the pilot operation amount is substantially constant (neutral).
It is not related to the supply flow rate from the hydraulic pressure source.

Therefore, even if the hydraulic pressure supply flow rate changes, there is no need to change the operation amount of the pilot valve by the electric control unit, and the hydraulic pressure control device does not have the override characteristic. Moreover, the deviation between the pressure command value and the detected pressure value is very small, and the linearity and reproducibility are excellent.

Further, even if the hydraulic pressure decreases, the electric control section does not have an integral compensation element, so that when the detected pressure value exceeds the pressure command value, the pilot valve is immediately operated to decrease the pressure. , Surge pressure can be kept low. Further, if the electric control unit is provided with a differential compensation element or further a secondary differential compensation element is added, the reduction of surge pressure is further improved. Further, a more optimal response waveform can be obtained by changing the compensation constant (eg, gain) of the electric control unit depending on the level of the detected pressure value.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a hydraulic pressure and electric circuit configuration diagram of an electric control type hydraulic control device according to a first embodiment of the present invention.

This hydraulic pressure control device controls the hydraulic pressures of a hydraulic pressure generation source 1 and a main valve 2 and a pilot valve 3 which control the hydraulic pressure of a hydraulic fluid supply line (line) 4 to a load by the hydraulic pressure generation source 1. A pressure transducer (pressure sensor) 5 that detects and generates an electric signal, a pressure command signal Pc, and an electric signal (hereinafter referred to as “feedback signal”) Pf from the pressure transducer 5 are received so that the deviation becomes small. And an electric control section 6 for generating an operation signal Su to the pilot valve 3. In addition, 7 is a reservoir tank.

The main valve 2 is provided with a pressure port Pm to which a pressure liquid is supplied from the hydraulic pressure source 1 and tank ports Tm1 and Tm2 which flow back to the reservoir tank 7, and the displacement of the spool 8 which is a built-in valve body. The pressure of the pressure port Pm is controlled according to

In the pilot valve 3, the spool 12 is displaced by an electromagnetic actuator 10 which generates a thrust force according to the electric signal Su from the electric control unit 6 and a spring 11 which opposes the thrust, and the displacement is caused by the thrust force of the electromagnetic actuator 10. After that, the moving speed of the spool 8 of the main valve 2 is controlled.

The pilot valve 3 is a three-way valve, the pressure port Pp of which communicates with the pressure liquid supply line 4 and the tank port Tp of which communicates with the reservoir tank 7, and the control port Cp provided between them communicates with the main valve 2. Of the pilot port Pi. The main valve 2 has its spool 8
The supply hydraulic pressure from the hydraulic pressure generation source 1 is made to act on one end portion, and the hydraulic pressure of the control port Cp of the pilot valve 3 is made to act on the other end portion.

The electric control unit 6 receives the pressure command signal Pc and the feedback signal Pf from the pressure converter 5 and causes the electromagnetic actuator 10 of the pilot valve 3 to reduce the deviation and make both signal values coincide. On the other hand, the operation signal S
Output u. The spool 12 of the pilot valve 3 is slidably displaced in the x direction so that the pressing force of the electromagnetic actuator 10 excited by the operation signal Su and the biasing force of the spring 11 are balanced. Thereby, the main valve 4
The spool 8 of 4 is slidably displaced in the X direction.

For example, when the pressure command signal Pc becomes a boost command, the electric control section 6 displaces the spool 10 of the pilot valve 3 to the right (+) so that the electromagnetic actuator 10 operates.
The operation signal Su for increasing the pressing force of, that is, increasing the exciting current is output. Thereby, the control port Cp of the pilot valve 3 communicates with the pressure port Pp,
Since it communicates with the pilot port Pi of the main valve 2, an inflow rate is generated there and the spool 8 of the main valve 2 is displaced downward (+).

Therefore, the pressure port Pm of the main valve 2
The flow path between the tank port Tm and the tank port Tm is narrowed, and the liquid pressure of the pressure port Pm and the pressure liquid supply line 4 communicating therewith rises. As a result, when the feedback signal Pf which is the detection signal of the pressure converter 5 rises and approaches the pressure command signal Pc, the operation signal Su output by the electric control unit 6 gradually decreases, so that the spool 12 of the pilot valve 3 Is displaced to the left (-), which reduces the displacement speed of the spool 8 of the main valve 2.

When the feedback signal Pf reaches the value of the pressure command signal Pc, the spool 12 of the pilot valve 3 is in the neutral position and the spool 8 of the main valve 2 is settled. Therefore, the openings of the pressure port Pm and the tank port Tm are settled, and a constant pressure is maintained. The operation performed when the pressure command signal Pc becomes the step-down command is the reverse of the above-described operation.

FIG. 2 shows the pressure command P according to the first embodiment.
c, the displacement x of the spool 12 of the pilot valve 3, the main valve 2
6 is a waveform diagram showing the relationship between the displacement X of the spool 8 and the pressure change of the pressure liquid supply line 4. FIG.

According to this embodiment, when the spool (valve body) 8 of the main valve 2 controlled by the pilot valve 3 is settled at a certain position regardless of its displacement amount, the operation amount of the pilot valve 3 is almost the same. Since it is constant (neutral), it does not depend on the supply flow rate of the hydraulic pressure supply reduction 1. That is, it is possible to configure a hydraulic control device that does not have an override characteristic.
Similarly, the deviation (steady deviation) between the pressure command and the feedback signal which is the output of the pressure converter 5 becomes very small, and a hydraulic control device having excellent linearity and reproducibility can be realized.

Next, a second embodiment of the present invention is shown in FIG. This electrically controlled hydraulic pressure control device has a pilot valve 3 '.
A four-way valve is used as two control ports Cp1 and Cp2
And one of the control ports Cp1 communicates with the pilot port Pi1 on one end side of the spool 8 of the main valve, and the other control port Cp2 communicates with the pilot port Pi2 on the other end side of the spool 8, respectively. The hydraulic pressures of the first and second control ports Cp1 and Cp2 of the pilot valve 3'are applied to both ends of the spool 8 of the valve 2, respectively.

The structure of the main valve 8 is slightly different from that of the first embodiment shown in FIG. 1, but the same reference numerals are attached for convenience. The other structure is similar to that of the first embodiment shown in FIG. 1, and therefore its explanation is omitted. This example also
The same action and effect as those of the first embodiment can be obtained.

FIG. 4 shows a third embodiment of the present invention. This electrically controlled hydraulic control device is a poppet valve 20 which is a main valve.
Is used to urge the poppet 21, which is the valve body, against the seat portion 23 having a conical surface by a relatively weak spring 22, and the pilot port Pi has the same pilot valve 3 as that of the first embodiment shown in FIG. To communicate with the control port Cp of the pressure port Pm and control the escape flow rate of the pressure liquid supplied to the pressure port Pm from the hydraulic pressure generation source 1 via the pressure liquid supply line 4 to the tank port Tm, thereby controlling the pressure. The other structure is similar to that of the first embodiment shown in FIG.

According to the third embodiment, since the spring 22 for urging the poppet 21 is provided, the minimum control pressure is increased by that amount, but even if the flow rate is extremely small, the minimum pilot pressure is reduced. There are advantages to be obtained. Other functions and effects are similar to those of the first and second embodiments.

FIG. 5 shows a fourth embodiment of the present invention. This electrically controlled hydraulic control device is basically the same as the first embodiment, although the structure of the main valve is slightly different from the main valve 2 in the first embodiment and the connection with the pilot valve 3 is also slightly different. ing. Note that the pressure port Pp and the tank port Tp of the pilot valve 3 are left-right inverted from those of the first embodiment shown in FIG.

The main valve 2'is provided with a control port Cm.
Is provided and the supply of the pressure liquid from the pressure generation source 1 flowing into the pressure port Pm and the rate of escape to the tank port Tm1 are varied so that the liquid pressure of the control port Cm, that is, the liquid pressure of the pressure liquid supply line 9 is set. Control. The main valve 2'applies hydraulic pressure to the control port Cp of the pilot valve (three-way valve) 3 on one end of the spool 8 ', which is its valve body, and is attached to the other end by a spring 15. It is exerting power.

In the fourth embodiment, for example, when the pressure command signal Pc becomes a boost command, the electric control unit 6 presses the electromagnetic actuator 10 so as to displace the spool 12 of the pilot valve 3 to the right (+). Is output, that is, an operation signal Su that increases the exciting current is output.
As a result, the control port Cp of the pilot valve 3 communicates with the tank port Tp, which communicates with the pilot port Pi of the main valve 2 ', so that a discharge flow rate is generated there and the spool 8 of the main valve 2'is generated. ′ Is displaced upward (+).

Therefore, the control port Cm of the main valve 2'opens to the pressure port Pm, and the flow rate of inflow from the pressure port Pm to the control port Cm is generated.
m is boosted. The boosting speed at this time is determined by the inflow flow rate and the operating speed of the conduit communicating with the pilot port Pi and the electromagnetic actuator 10.

When the feedback signal Pf from the pressure converter 5 approaches the value of the pressure command signal Pc, the electric control unit 6 decreases the operation signal Su, and the spool 12 of the pilot valve 3 is displaced leftward, Cross the neutral state. As a result, the control port Cp of the pilot valve 3 opens to the pressure port Pp, and a flow rate of inflow from the pressure port Pp to the control port Cp is generated. Thereby,
The spool 8'of the main valve 2'is displaced downward (-), and the pressure rising speed is reduced.

Feedback signal P from the pressure transducer 5
When f reaches the value of the pressure command signal Pc, the pilot valve 3
The spool 12 returns to the neutral position again, and the spool 8'of the main valve 2'also stops at the substantially neutral position, and the control port Cm is closed to maintain its pressure. The operation performed when the pressure command signal Pc becomes the step-down command is the reverse of the above-described operation.

FIG. 6 shows the pressure command Pc according to this embodiment.
And the displacement x of the spool 12 of the pilot valve 3 and the main valve 2 '
7 is a waveform diagram showing the relationship between the displacement X of the spool 8 ′ and the pressure change in the pressure liquid supply line 9. Also according to the fourth embodiment, a hydraulic pressure control device having a small steady deviation and excellent linearity and reproducibility can be realized, as in the case of each of the above-described embodiments.

FIG. 7 shows a fifth embodiment of the present invention. This electrically controlled hydraulic pressure control device is used as a pilot valve in FIG.
The same 4-way valve as the pilot valve 3'of the second embodiment shown in FIG. 4 is used, and the main valve 2'is slightly different from the above-described fourth embodiment, but is attached with the same reference numeral for convenience. . Even with this configuration, the same operation and effect as those of the above-described respective embodiments can be obtained.

Next, FIG. 8 shows a circuit configuration example of the electric control section 6 in each of these embodiments. This circuit includes an inverting amplifier circuit 61 for inverting and amplifying the hydraulic pressure detection signal Pf from the pressure converter 5, a proportional compensation circuit 62 for additionally inputting its output and a pressure command signal Pc, and a differential of the output of the inverting amplifier circuit 61. Differential compensation circuit 63 for inverting and amplifying, and an inverting amplifier circuit 64 for additionally inputting the output thereof and the output of the proportional compensation circuit 62.
And a driver circuit (voltage / current conversion circuit) 65 that drives the electromagnetic actuator 10 of the pilot valve 3 or 3'according to its output.

The gain (Gai
The relationship between n) and the phase is shown in FIG. D in this figure
The section indicated by is used as differential compensation. If the differential constant in that case is kd, then kd = C ₁ R ₂ . Since the differential compensating circuit 63 is provided together with the proportional compensating circuit 62 in this way, since the degree of pressure change is captured in a closed loop and the pilot valve is operated quickly, the response waveform can be made smooth quickly and the integral compensating element Since it does not have a high surge pressure, high surge pressure does not occur.

FIG. 10 shows another circuit configuration example of the electrical control section 6. This circuit is provided with a filter circuit 66 and a second-order differential compensation circuit 67, an inverting amplifier circuit 68, and a bias addition circuit 69 in addition to the above-described circuit configuration shown in FIG. The feature is that the circuit 67 is provided. This is intended to make the control pressure waveform smoother.

That is, the differential compensation circuit 63 tries to close the inflow rate, that is, the opening degree of the valve body of the main valve quickly according to the rate of change of pressure, while the secondary differential compensation circuit 67 controls the valve body of the main valve. It is intended to reduce the displacement speed as quickly as possible.

For example, when the spool 12 of the pilot valve 3 or 3'overshoots the operation signal Su of the electric control unit 6, a high displacement of the main valve 2 or 2'spool 8 or 8'is generated. There is an effect of suppressing the speed, and the disturbance of the waveform due to the effect can be suppressed. By doing so, it is possible to eliminate instability due to an abnormal decrease in the viscosity of the hydraulic oil.

FIG. 11 is a block diagram showing still another example of the electric control unit 6, which shows the deviation signal Pe between the pressure command signal Pc detected by the difference detection circuit 70 and the feedback signal Pf from the pressure converter 5. The variable gain amplifier 71 amplifies the gain, and the gain (compensation constant) is changed according to the value of the feedback signal Pf. Reference numeral 65 denotes a V / I conversion circuit as a driver circuit, which causes a current corresponding to the operation signal Su to flow through the coil of the electromagnetic actuator 10 of the pilot valve 3 or 3'described above.

The displacement speed of the spool 8 or 8'of the main valve 2 or 2'in each of the above-described embodiments is proportional to the displacement (opening area) of the spool 12 of the pilot valve 3 or 3 '.
This is a non-linear element that changes with pressure conditions.
That is, q = C · A√ (Δ
P / ρ) and the flow coefficient C and the fluid density ρ are substantially constant, the flow rate q is proportional to the opening area A and the square root of the differential pressure ΔP. )
The displacement speed of is proportional to the flow rate q.

Therefore, in order to give a constant displacement speed (pressure change speed) to the valve body of the main valve with respect to the deviation amount between the pressure command and the pressure feedback of an arbitrary value under all pressure conditions, the pressure command signal Pc And an amount of deviation of the feedback signal Pf, in the process of generating the manipulated variable of the pilot valve from now on, there is an amplifier having a gain characteristic inversely proportional to the square root of the pressure feedback value as shown by the broken line in FIG. Is desirable.

However, if the construction of such an amplifier is difficult, then the A as shown by the alternate long and short dash line or solid line in FIG.
It is practically sufficient to use the variable gain amplifier 71 (FIG. 11) having the GC characteristic (substantially inversely proportional to the pressure feedback value).

As a result, the gain of the variable gain amplifier 71 changes as shown in FIG. 13, and the manipulated variable (Su) output with respect to the deviation amount (Pe) changes according to the value of the feedback signal Pf. Become. As a result, it is possible to configure a hydraulic control device having high responsiveness in all pressure regions and ensuring stability.

[0048]

As described above, according to the electric control type hydraulic control device of the present invention, the linearity, reproducibility and responsiveness of the control hydraulic pressure with respect to the pressure command value are good, and the override characteristic is excellent. High control accuracy can be obtained. Further, the surge pressure generated when the load of the actuator or the like is stopped can be reduced. Moreover, the structure is relatively simple and can be implemented at low cost.

[Brief description of drawings]

FIG. 1 is a hydraulic pressure and electric circuit configuration diagram of an electric control type hydraulic control device according to a first embodiment of the present invention.

FIG. 2 is a waveform diagram showing the relationship between the pressure command, the displacement of the spool of the pilot valve and the main valve, and the pressure change of the pressure liquid supply line according to the first embodiment of FIG.

FIG. 3 is a view similar to FIG. 1 showing a second embodiment of the present invention.

FIG. 4 is a view similar to FIG. 1, showing a third embodiment of the present invention.

FIG. 5 is a view similar to FIG. 1, showing a fourth embodiment of the present invention.

FIG. 6 is a waveform diagram showing the relationship between the pressure command, the displacement of the spool of the pilot valve and the main valve, and the pressure change of the pressure liquid supply line according to the fourth embodiment of FIG.

FIG. 7 is a view similar to FIG. 1, showing a fifth embodiment of the present invention.

FIG. 8 is a circuit diagram showing a circuit configuration example of an electric control unit 6 in each embodiment of the present invention.

9 is a diagram showing a relationship between a gain (Gain) and a phase (Phase) by the differential compensation circuit 63 in FIG.

FIG. 10 is a circuit diagram showing another circuit configuration example of the electric control unit 6 in each embodiment of the present invention.

FIG. 11 is a block diagram showing still another circuit configuration example of the electric control unit 6 in each embodiment of the present invention.

FIG. 12 is a diagram for explaining the gain characteristic of the amplifier with respect to the pressure feedback value.

13 is a diagram showing the relationship among the gain of the variable gain amplifier 71 in FIG. 11, the deviation amount, and the operation amount.

[Explanation of symbols]

1 Hydraulic pressure source 2, 2'Main valve (spool valve) 20 Main valve (poppet valve) 3 Pilot valve (3
One-way valve 3'Pilot valve (four-way valve) 4,9 Pressure liquid supply line 5 Pressure converter 6 Electric control unit 7 Reservoir tank 8,8 'Spool (valve body) 10 Electromagnetic actuator 11,15,22 Spring 12 Pilot Valve spool 12 Compensator 13, 14 Subtraction circuit 15,
16 Switching circuit 21 Poppet (valve body) 62 Proportional compensation circuit 6
3 Differential Compensation Circuit 65 Driver Circuit (Voltage / Current Conversion Circuit) 67 Secondary Differential Compensation Circuit 71 Variable Gain Amplifier

Claims (9)

[Claims] 1. A main valve having a pressure port for receiving a pressure fluid supplied from a fluid pressure generation source and a tank port for returning to a reservoir tank, and controlling the pressure of the pressure port in accordance with the displacement of a valve element incorporated therein. And the spool is displaced by an electromagnetic actuator that generates thrust corresponding to an electric signal and a spring that opposes the electromagnetic actuator, and the displacement is determined by the thrust of the electromagnetic actuator. A pilot valve for controlling the moving speed of the pressure sensor, a pressure converter for detecting the pressure of the pressure fluid supply pipe from the fluid pressure generation source to the pressure port of the main valve and generating an electric signal, and a pressure command signal An electric signal from the pressure converter is received, and an operation signal is generated for the electromagnetic actuator of the pilot valve so that both signal values match. An electric control type hydraulic control device comprising an electric control unit. 2. The electrically controlled hydraulic pressure control device according to claim 1, wherein the pilot valve is a three-way valve, and the main valve has a liquid supply source from the hydraulic pressure generation source at one end of its valve body. An electric control type hydraulic control device, wherein pressure is applied and hydraulic pressure of a control port of the pilot three-way valve is applied to the other end. 3. The electric control type hydraulic control device according to claim 1, wherein the pilot valve is a four-way valve, and the main valve has first and second pilot four-way valves at both ends of its valve body. 2. An electrically controlled hydraulic pressure control device, wherein hydraulic pressure of the control port 2 is applied. 4. A pressure port that receives supply of a pressure fluid from a fluid pressure generation source, a tank port that recirculates to a reservoir tank, and a pressure port that is provided between the pressure port and the tank port and that accommodates the displacement of a built-in valve element. The spool is displaced by a main valve that controls the pressure of the control port, an electromagnetic actuator that generates thrust according to an electric signal, and a spring that opposes the thrust, and the displacement is determined by the thrust of the electromagnetic actuator. A pilot valve that supplies pilot pressure liquid to control the moving speed of the valve body, a pressure converter that detects pressure liquid at the control port of the main valve and generates an electric signal, a pressure command signal and the pressure conversion And an electrical signal from the controller to generate an operation signal to the electromagnetic actuator of the pilot valve so that the two signal values match. An electrically controlled hydraulic control device comprising a control section. 5. The electric control type hydraulic control device according to claim 4, wherein the pilot valve is a three-way valve, and the main valve has a control port of the pilot three-way valve at one end of its valve body. An electrically controlled hydraulic pressure control device, wherein hydraulic pressure is applied and an urging force by a spring is applied to the other end. 6. The electric control type hydraulic control device according to claim 5, wherein the pilot valve is a four-way valve, and the main valve has first and second pilot four-way valves at both ends of the main spool, respectively. An electric control type hydraulic pressure control device characterized in that the hydraulic pressure of the control port is applied. 7. The electric control type hydraulic control device according to claim 1, wherein the electric control section includes a proportional compensation element or a proportional compensation element and a differential compensation element. An electrically controlled hydraulic pressure control device. 8. The electric control type hydraulic control device according to claim 1, wherein a compensation constant is changed in the electric control unit according to a value of an electric signal from the pressure converter. An electrically controlled hydraulic pressure control device comprising means for controlling. 9. The electric control type hydraulic control device according to claim 1, wherein the electric control unit includes a proportional compensation element, a differential compensation element and a second derivative compensation element. An electrically controlled hydraulic pressure control device characterized in that