JP6304881B2 - Fluid circuit control device with accumulator - Google Patents

Description

  The present invention relates to hydraulic devices for automobiles, construction machines, transport vehicles, industrial vehicles, industrial machines, and the like, and more particularly, to a control device for a fluid circuit including an accumulator.

It is known that the volume Vw represented by the following equation is discharged from the accumulator, where P1 is the gas pressure in the accumulator, P2 is the minimum operating pressure, P3 is the maximum operating pressure, and V1 is the volume of the accumulator.
However, m and n are polytropic indices at the time of accumulation and at the time of discharge, respectively.

  Conventionally, as an example of pressure accumulation oil control of a hydraulic energy regeneration system using an accumulator, for example, Japanese Patent Laid-Open No. 10-175458 (hereinafter referred to as “Patent Document 1”) and Japanese Patent Laid-Open No. 2008-19910 (hereinafter referred to as “Patent Document 1”). (Referred to as “Patent Document 2”) (hereinafter referred to as “conventional technology”), both of which have a certain value of the pressure signal from the pressure detection device installed in the circuit. As a boundary, regeneration of the accumulator in the accumulator is turned on and off by a switching valve. The load pressure (minimum operating pressure) of the supplied circuit and the accumulator load during accumulator as shown in Equation 1 Control of the amount of inflow into the circuit in consideration of the sum of the discharge amount from the accumulator by the pressure (maximum operating pressure) and the discharge amount from the pump is not performed.

FIG. 5 shows an example of a hydraulic circuit using an accumulator according to the prior art.
In FIG. 5, the hydraulic circuit includes a hydraulic pump 52 driven by a drive mechanism 51 such as an engine or an electric motor, a switching valve 53, a hydraulic cylinder 54, a relief valve 55, a hydraulic tank 56, an electromagnetic switching valve 57, an accumulator 58, a remote control valve. 61, oil passages 59, 60, 64 to 71, and signal oil passages 62, 63.
The hydraulic pump 52 is connected to the drive mechanism 51 and rotates with power from the drive mechanism to supply pressure oil to the downstream side through the oil passage 59. The pressure oil discharged from the hydraulic pump 52 flows into the switching valve 53 through the oil passage 59. The switching valve 53 is a 6-port 3-position type open center type switching valve, and in its neutral position, all of the pressure oil discharged from the hydraulic pump 52 flows into the tank 56 through the oil passage 60. Further, the remote control valve 61 is a variable pressure reducing valve that operates the operation lever 61a in the direction of expansion or contraction of the cylinder so that the pilot secondary pressure proportional to the lever operation amount as shown in FIG. Alternatively, the signal is supplied to the signal port 53a or 53b of the switching valve 53 through 63, thereby switching to the “extended” position or the “contracted” position. Furthermore, in this circuit, when the cylinder rod 54a reaches the end of expansion or contraction, or when a sudden load is applied to the cylinder 54, the oil in the circuit becomes blocked and becomes abnormally high pressure. In order to prevent breakage, a relief valve 55 is provided so that high-pressure oil is discharged to the tank 56 through the oil passages 64 and 65.

  When the operation lever 61a of the remote control valve 61 is operated in the extending direction and the switching valve 53 is switched to the extended position, the pressure oil from the hydraulic pump 52 flows into the oil chamber 54-1 of the cylinder 54 through the oil passages 66 and 67. Then, the oil in the oil chamber 54-2 passes through the oil passage 68 and is discharged to the tank 56 through the oil passage 69 through the switching valve 53. Thereby, the rod 54a of the cylinder 54 operates in the extending direction. Further, when the operation lever 61a of the remote control valve 61 is operated in the contracted direction and the switching valve 53 is switched to the contracted position, the pressure oil from the hydraulic pump 52 passes through the oil passages 66 and 68 and the oil chamber 54-2 of the cylinder 54. The oil in the oil chamber 54-1 passes through the oil passage 67, passes through the switching valve 53, passes through the oil passage 69, and is discharged to the tank 56. Thereby, the rod 54a of the cylinder 54 operates in the contraction direction.

The switching valve 53 has an opening characteristic as shown in FIG. 7, and as described above, as the pilot pressure increases, the opening amount increases as the operation amount of the operation lever 61a of the remote control valve 61 increases. The amount of oil supplied to the cylinder 54 is increased, and the rod operating speed of the cylinder 54 is increased. That is, the cylinder rod speed is controlled according to the operation amount of the operation lever 61a of the remote control valve 61. The relationship between the lever stroke (pilot secondary pressure) and the cylinder rod extension speed is shown by the solid line in FIG. The electromagnetic switching valve 57 is a 2-port 2-position type normally closed electromagnetic switching valve, which is located between an oil passage 70 branched from the oil passage 59 and an oil passage 71 connected to the accumulator 58. It is provided to control the oil inflow and outflow between 59 and the accumulator 58.
It should be noted that the present invention relates to control when oil flows from the accumulator 58 to the oil passage 59, and the description of the pressure accumulating means for the oil into the accumulator 58 is omitted because it is not directly related to the present invention. .

この時、例えば、操作レバー６１ａを伸び方向に操作量Ｌｘで操作してシリンダのロッド５４ａが伸び方向に作動しているときに、電磁切換弁５７が切り換わると、アキュムレータ５８内の油が油路５９に一気に流入し、吐出が終わるまでにシリンダ５４への流入流量が急激に変化し、図８のＳ部（破線部）で示すようにシリンダロッド５４ａのスピードが一時的に変化する。 Now, let us consider a case in FIG. 5 where the electromagnetic switching valve 57 is switched when some set condition is satisfied, and the accumulated oil in the accumulator 58 is discharged to the oil passage 59. If the pressure in the oil passage 59 immediately before the switching of the electromagnetic switching valve 57 is PL and the pressure in the accumulator 58 is PA (where PL <PA), the electromagnetic switching valve 57 is switched and the oil passage 70 and the oil passage 71 are connected. Assuming that the oil passage 71 is connected and the pressure in the oil passage 71 is reduced to PL, a part of the pressure-accumulated oil in the accumulator 58 is discharged into the oil passage 59 at a stroke according to the equation (1).

At this time, for example, when the solenoid switching valve 57 is switched when the operating lever 61a is operated in the extending direction with the operation amount Lx and the cylinder rod 54a is operating in the extending direction, the oil in the accumulator 58 is oiled. The inflow flow rate into the cylinder 54 suddenly changes before the discharge ends, and the speed of the cylinder rod 54a temporarily changes as shown by S part (broken line part) in FIG.

JP-A-10-175559 JP 2008-19910 A

The prior art described above has the following drawbacks and problems.
(1) Control of the amount of inflow into the circuit in consideration of the sum of the discharge amount from the accumulator 58 and the discharge amount from the pump 52 by the load pressure of the supplied circuit and the load pressure at the time of pressure accumulation in the accumulator 58 as shown in Equation 1. When the switching valve 53 is switched, if pressure oil suddenly flows into the circuit from the accumulator 58, for example, a shock due to a rapid speed change of a cylinder or the like as shown in part S of FIG. May occur.
(2) Power saving by so-called hydraulic energy regeneration by reducing the amount of oil discharged from the pump 52 in anticipation of the amount of oil discharged from the accumulator 58 (operating with reduced pump output by reducing the amount of discharge) When the operation is performed, since the total amount of oil discharged from the accumulator 58 and the pump flow rate is not appropriately controlled, there is a risk that the speed of an actuator such as a cylinder will be excessive or insufficient.

According to the present invention, a proportional electromagnetic throttle valve is provided in a fluid circuit, and the opening of the proportional electromagnetic throttle valve is controlled based on the pressure of the fluid circuit and the pressure in the accumulator so that the discharge flow rate from the accumulator can be arbitrarily controlled. Another object of the present invention is to provide a fluid circuit control device capable of preventing an abnormality caused by a rapid speed change of an actuator.
In addition, the present invention provides a fluid circuit control device that can control the total discharge amount of the discharge amount from the accumulator and the discharge amount from the pump to be constant, and can prevent the occurrence of excessive or insufficient actuator speed. For the purpose.

In order to achieve the above object, a control apparatus for a fluid circuit including an accumulator according to the present invention includes a fluid pressure pump, a fluid pressure actuator driven by fluid discharged from the fluid pressure pump, and the fluid pressure. A switching valve that is connected between the pump and the fluid pressure actuator and controls the fluid supplied to the fluid pressure actuator in response to an operation signal from the operation means, and connects the fluid pressure pump and the fluid pressure actuator. In a fluid circuit comprising an accumulator for fluid pressure energy storage connected to a first flow path,
A proportional electromagnetic throttle valve disposed in a second flow path connecting the first flow path and the accumulator;
Pressure detection means provided on the first flow path side and the first flow path side of the proportional electromagnetic throttle valve of the second flow path;
A controller for controlling the opening degree of the proportional electromagnetic throttle valve,
The controller and the signal input port of the proportional electromagnetic throttle valve are connected by an electric signal line, and the controller and the respective pressure detection means are connected by an electric signal line,
When the accumulator fluid in the accumulator is discharged to the first flow path via the proportional electromagnetic throttle valve, the accumulator is controlled by controlling the opening of the proportional electromagnetic throttle valve based on the pressures of the pressure detecting means. It is characterized in that the discharge flow rate from can be controlled arbitrarily.

  According to the first feature, when the pressure accumulation fluid in the accumulator is discharged to the first flow path side via the proportional electromagnetic throttle valve, the opening degree of the proportional electromagnetic throttle valve is controlled based on the respective pressures of the pressure detecting means. Since the discharge flow rate from the accumulator can be arbitrarily controlled, when the switching valve as in the prior art is switched, a cylinder or the like caused by the pressure oil suddenly flowing from the accumulator into the first oil passage Even when the switching valve is switched, an actuator such as a cylinder can be smoothly operated without causing an abnormality such as a shock due to a sudden speed change of the actuator.

  In the fluid circuit control device equipped with the accumulator of the present invention, secondly, in the first feature, the controller and the flow rate control means of the fluid pressure pump are connected by an electric signal line, and the controller The total discharge amount of the discharge flow rate and the discharge amount from the fluid pressure pump can be controlled to be constant by the controller.

  According to the second feature, the discharge flow rate of the hydraulic pump can be arbitrarily reduced by the electric signal from the controller in anticipation of an increase in the oil amount to the cylinder due to the discharge oil from the accumulator. The total amount of oil discharged from the accumulator can be exactly the same as the amount of oil supplied to the cylinder when there is no oil discharged from the accumulator. Appropriate power saving can be realized without causing excessive or insufficient speed of an actuator such as a cylinder due to the total oil amount not being controlled properly.

The present invention has the following excellent effects.
(1) When the pressure accumulation fluid in the accumulator is discharged to the first flow path side via the proportional electromagnetic throttle valve, the opening degree of the proportional electromagnetic throttle valve is controlled based on the respective pressures of the pressure detection means, and the accumulator The discharge flow rate from the cylinder can be controlled arbitrarily, so that when the switching valve as in the prior art is switched, the pressure oil from the accumulator suddenly flows into the first oil passage suddenly of the actuator such as a cylinder. An actuator such as a cylinder can be smoothly operated even when the switching valve is switched without causing an abnormality such as a shock due to a speed change.

(2) The discharge flow rate of the hydraulic pump can be reduced arbitrarily according to the electrical signal from the controller in anticipation of an increase in oil volume to the cylinder due to the discharge oil from the accumulator. The total amount of oil discharged from the accumulator and the pump flow rate as in the conventional technology is the same as the amount of oil supplied to the cylinder when there is no oil discharged from the accumulator. Appropriate power saving can be realized without causing an excess or deficiency in the speed of an actuator such as a cylinder due to the fact that is not controlled properly.

It is a block diagram of the control apparatus of the fluid circuit provided with the accumulator which concerns on the Example of this invention. It is a figure which shows the opening characteristic of the proportional electromagnetic type throttle valve which concerns on the Example of this invention. It is a figure which shows the discharge flow volume from the accumulator which concerns on the Example of this invention. It is a figure which shows the flow volume characteristic of the fluid pressure pump which concerns on the Example of this invention. It is a block diagram of the control apparatus of the fluid circuit provided with the accumulator which concerns on a prior art. It is a figure which shows the relationship between the lever operation amount of the remote control valve which concerns on a prior art, and a pilot secondary pressure. It is a figure which shows the opening characteristic of the switching valve which concerns on a prior art. It is a figure which shows the relationship between the lever operation amount of the remote control valve which concerns on a prior art, and the elongation speed of a cylinder rod.

  EMBODIMENT OF THE INVENTION With reference to drawings, the form for implementing this invention is demonstrated illustratively based on an Example below. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

With reference to FIG. 1 thru | or FIG. 4, the control apparatus of the hydraulic circuit provided with the accumulator which concerns on the Example of this invention is demonstrated.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment for carrying out a fluid circuit control device equipped with an accumulator according to the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to a hydraulic circuit and is not limited to a hydraulic circuit or The present invention can be applied to a pneumatic circuit, and various changes, modifications, and improvements can be made based on the knowledge of those skilled in the art without departing from the scope of the present invention.

First, based on FIG. 1, the whole structure of the control apparatus of the hydraulic circuit provided with the accumulator which concerns on the Example of this invention is demonstrated.
In FIG. 1, the hydraulic circuit includes a hydraulic pump 2, a switching valve 3, a hydraulic cylinder 4, a relief valve 5, a hydraulic tank 6, an accumulator 8, a remote control valve 11, and a first oil driven by a driving mechanism 1 such as an engine or an electric motor. It comprises a passage 9, a second oil passage 10, other oil passages 14 to 20, signal oil passages 12 and 13, a proportional electromagnetic throttle valve 22, and a controller 25.
The present invention is particularly characterized in that it includes a proportional electromagnetic throttle valve 22 and a controller 25, which will be described in detail later.

  The hydraulic pump 2 is connected to the drive mechanism 1 and is rotated by power from the drive mechanism to supply pressure oil to the downstream side through the first oil passage 9. The pressure oil discharged from the hydraulic pump 2 flows into the switching valve 3 through the first oil passage 9. The switching valve 3 is a 6-port 3-position type open center type switching valve, and in its neutral position, the entire amount of pressure oil discharged from the hydraulic pump 2 flows into the tank 6 through the oil passage 20. The remote control valve 11 is the same as that of the conventional example. By operating the operation lever 11a in the direction of cylinder expansion or contraction with a variable pressure reducing valve, the pilot secondary pressure proportional to the lever operation amount is signaled. By being supplied to the signal port 3 a or 3 b of the switching valve 3 through the oil passage 12 or 13, the position is switched to the “extended” position or the “contracted” position. Furthermore, in this circuit, when the cylinder rod 4a reaches the end of expansion or contraction, or when a sudden load is applied to the cylinder 4 and the oil in the circuit is blocked, the oil pressure in the circuit becomes abnormal. A relief valve 5 is installed to prevent breakage, and high pressure oil is discharged to the tank 6 through the oil passages 14 and 15.

  When the operation lever 11a of the remote control valve 11 is operated in the extending direction and the switching valve 3 is switched to the extended position, the pressure oil from the hydraulic pump 2 flows into the oil chamber 4-1 of the cylinder 4 through the oil passages 16 and 17. Then, the oil in the oil chamber 4-2 is discharged through the oil passage 18 through the switching valve 3 and through the oil passage 19 to the tank 6. Thereby, the rod 4a of the cylinder 4 operates in the extending direction. Further, when the operation lever 11a of the remote control valve 11 is operated in the contracted direction and the switching valve 3 is switched to the contracted position, the pressure oil from the hydraulic pump 2 passes through the oil passages 16 and 18 and the oil chamber 4-2 of the cylinder 4. The oil in the oil chamber 4-1 passes through the oil passage 17, passes through the switching valve 3, passes through the oil passage 19, and is discharged to the tank 6. Thereby, the rod 4a of the cylinder 4 operates in the contracting direction.

  The switching valve 3 is the same as that of the conventional example, and has an opening characteristic as shown in FIG. As the height increases, the opening amount increases, the amount of oil supplied to the cylinder 4 increases, and the rod operating speed of the cylinder 4 increases. That is, the cylinder rod speed is controlled in accordance with the operation amount of the operation lever 11a of the remote control valve 11. The relationship between the lever stroke (pilot secondary pressure) and the cylinder rod extension speed is shown by the solid line in FIG.

The proportional electromagnetic throttle valve 22 is disposed in the second oil passage 10 connecting the first oil passage 9 and the accumulator 8, and the first oil passage side 10 a of the proportional electromagnetic throttle valve 22 of the second oil passage 10. The pressure detection devices 23 and 24 are provided on the anti-first oil passage side 10b, respectively.
The proportional electromagnetic throttle valve 22 is defined by JIS B0142, and is a throttle valve capable of controlling a throttle proportional to an electrical analog input signal. The term “throttle valve” is also defined in JIS B0142, and refers to a flow rate control valve without a pressure compensation function that regulates the flow rate by a throttle action.

The controller 25 controls the opening degree of the proportional electromagnetic throttle valve 22 and the flow rate of the fluid pressure pump 2.
The controller 25 and the signal input port 22 a of the proportional electromagnetic throttle valve 22 are connected by an electric signal line 30, and the proportional electromagnetic throttle valve 22 is controlled by an electric signal from the controller 25. Further, the controller 25 and the pressure detection devices 23 and 24 are connected by electric signal lines 28 and 29, respectively, and pressure signals from the respective pressure detection devices 23 and 24 are input to the controller 25. .
FIG. 2 shows the opening characteristics of the proportional electromagnetic throttle valve 22, which is controlled to an arbitrary opening degree (also referred to as “opening area”) by an electric signal from the controller 25.

The controller 25 and the flow rate control means of the hydraulic pump 2 are connected by an electric signal line so that the discharge amount of the hydraulic pump 2 can be controlled. Specifically, when the flow rate control means of the hydraulic pump 2 is constituted by the capacity control unit 2a of the hydraulic pump itself, the controller 25 and the capacity control unit 2a are connected by the electric signal line 31, and the control from the controller 25 is performed. The displacement control unit 2a is controlled by the signal to control the discharge amount of the hydraulic pump 2.
When the flow rate control means of the hydraulic pump 2 is constituted by the output shaft rotation speed control unit 1a of the drive mechanism 1, the controller 25 and the output shaft rotation speed control unit 1a are connected by an electric signal line 32, and the controller 25 The output shaft rotational speed control unit 1a is controlled by the control signal from, and the discharge amount of the hydraulic pump 2 is controlled.

The flow rate through the opening of the proportional electromagnetic throttle valve 22 is Q, the pressure on the first oil path side 10a of the second oil path 10 is PL, the pressure on the anti-first oil path side 10b is PA, and the opening of the proportional electromagnetic throttle valve 22 is open. Assuming that the partial cross-sectional area is A, the following equation 2 is established by the orifice equation. However, K represents a constant.

Now, the proportional electromagnetic throttle valve 22 is in a closed state, the operation lever 11a of the remote control valve 11 is operated with the operation amount Lx in the extending direction, and the pressure when the rod 4a of the cylinder 4 is operating in the extending direction is PL. Assuming that the pressure in the accumulator 8 is PA (where PL <PA), the proportional electromagnetic throttle valve 22 is opened, and the volume of oil that can be discharged to the first oil passage 9 side is Vm, The volume Vm of oil discharged to the first oil passage 9 side is expressed by the following equation.

When the proportional electromagnetic throttle valve 22 is opened and the accumulated oil in the accumulator 8 is discharged to the first oil passage 9 through the second oil passage 10, the controller 25 detects the pressure detection devices 23 (Px) and 24 ( Py) while adjusting the opening cross-sectional area A of the proportional electromagnetic throttle valve 22 in the equation 2 while detecting the pressure signal from the Py), for example, as shown in FIG. The flow rate Q flowing through the opening, that is, the flow rate discharged from the accumulator 8 can be arbitrarily controlled.
Note that the area Sv (shaded portion) in FIG. 3 corresponds to the above Vm.

On the other hand, the discharge flow rate of the hydraulic pump 2 is controlled by the capacity control unit 2a or the output shaft rotation speed control unit 1a by an electric signal from the controller 25, for example, as shown in FIG. In view of the increase in the amount of oil to the cylinder 4 due to the oil, it is possible to control the pump flow rate as indicated by the broken line portion T. That is, the sum of the flow rate Qp from the hydraulic pump 2 and the discharge oil Q from the accumulator 8 is the amount of oil supplied to the cylinder 4 when there is no discharge oil Q from the accumulator 8, that is, the set proper supply oil amount. Can be exactly the same.
In addition, the controller 25 controls the opening cross-sectional area A of the proportional electromagnetic throttle valve 22 by an electric signal while detecting the pressure signals from the pressure detection devices 23 (Px) and 24 (Py) in advance. As shown in FIG. 4, the discharge flow rate Q from the accumulator 8 as shown in FIG. 3 is arbitrarily controlled, and at the same time, the displacement control unit 2a of the hydraulic pump 2 or the output shaft speed control unit 1a is controlled by an electric signal. Thus, an arithmetic circuit for controlling the pump flow rate as indicated by the broken line portion T in consideration of an increase in the oil amount to the cylinder 4 due to the discharge oil from the accumulator 8 is incorporated.

According to the above, the hydraulic circuit control device including the accumulator according to the embodiment of the present invention has the following effects.
(1) When the proportional electromagnetic throttle valve 22 is opened and the accumulated oil in the accumulator 8 is discharged through the second oil passage 10 to the first oil passage 9 side, the controller 25 performs pressure detection devices 23 (Px) and 24 While detecting the pressure signal from (Py), the flow rate Q discharged from the accumulator 8 is adjusted by adjusting the opening cross-sectional area A of the proportional electromagnetic throttle valve 22 in Formula 2 with the electrical signal from the controller 25. Since it can be arbitrarily controlled, when the switching valve as in the prior art is switched, a rapid change in the speed of an actuator such as the cylinder 4 due to a sudden flow of pressure oil from the accumulator 8 into the first oil passage 9 It is possible to discharge into the first oil passage 9 without causing an abnormality such as a shock due to.
(2) When performing power saving by regenerating hydraulic energy by reducing the amount of oil discharged from the hydraulic pump 2 in anticipation of the amount of oil discharged from the accumulator 8, the controller 25 detects the pressure detection devices 23 (Px) and 24 ( The flow rate Q discharged from the accumulator 8 is arbitrarily adjusted by adjusting the opening cross-sectional area A of the proportional electromagnetic throttle valve 22 in Formula 2 with the electrical signal from the controller 25 while detecting the pressure signal from Py). At the same time, the discharge flow rate of the hydraulic pump 2 depends on the discharge oil from the accumulator 8 by controlling the capacity control unit 2a or the output shaft speed control unit 1a with an electric signal from the controller 25. By accumulating the amount of oil to the cylinder 4 and arbitrarily reducing the flow rate Qp from the hydraulic pump 2, the accumulator Since the sum of the oil discharged from the accumulator 8 can be made exactly the same as the amount of oil supplied to the cylinder 4 when there is no oil Q discharged from the accumulator 8, the amount discharged from the accumulator and the pump as in the prior art Appropriate power saving can be realized without causing an excess or deficiency in the speed of an actuator such as a cylinder due to the fact that the total oil amount of the flow rate is not appropriately controlled.

  Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments, and modifications and additions within the scope of the present invention are included in the present invention. It is.

  For example, in the above-described embodiment, the oil is described as the fluid of the fluid circuit. However, it goes without saying that the present invention can be applied to all fluids other than oil, for example, a circuit using water pressure or air pressure. The present invention can also be applied to.

  Further, for example, in the above embodiment, the accumulator is not particularly described. However, the accumulator in the present invention is one of devices used in hydraulic and pneumatic fluid devices, and is a device for storing high-pressure fluid. Meaning, a typical example is the bladder type.

  Further, for example, the hydraulic pump is not particularly described in the above embodiment, but examples thereof include a screw pump, a gear pump, a vane pump, and a plunger pump.

1 Drive mechanism 2 Hydraulic pump (fluid pressure pump)
3 switching valve 4 hydraulic cylinder 5 relief valve 6 hydraulic tank 8 accumulator 9 first oil passage (first passage)
10 Second oil passage (second passage)
11 Remote control valve 12, 13 Signal oil passage 14-20 Oil passage
22 Proportional electromagnetic throttle valve 23 Pressure detection device 24 Pressure detection device 25 Controller 28 to 32 Electric signal line

Claims (2)

A fluid pressure pump, a fluid pressure actuator driven by a fluid discharged from the fluid pressure pump, and the fluid pressure pump connected to the fluid pressure pump and the fluid pressure actuator, and the fluid pressure according to an operation signal from an operation means. In a fluid circuit comprising a switching valve for controlling a fluid supplied to an actuator, and an accumulator for storing fluid pressure energy connected to a first flow path connecting the fluid pressure pump and the fluid pressure actuator,
A proportional electromagnetic throttle valve disposed in a second flow path connecting the first flow path and the accumulator;
Pressure detecting means provided on the first flow path side of the proportional electromagnetic throttle valve of the second flow path and pressure detecting means provided on the side opposite to the first flow path;
A controller for controlling the opening degree of the proportional electromagnetic throttle valve,
The controller and the signal input port of the proportional electromagnetic throttle valve are connected by an electric signal line, and the controller and the respective pressure detection means are connected by an electric signal line,
Pressure detecting means provided on the first flow path side of the proportional electromagnetic throttle valve of the second flow path when discharging the pressure accumulation fluid in the accumulator to the first flow path side via the proportional electromagnetic throttle valve; The discharge flow rate from the accumulator can be arbitrarily controlled by controlling the opening cross-sectional area of the proportional electromagnetic throttle valve while detecting the pressure signal from the pressure detection means provided on the side opposite to the first flow path. A fluid circuit control device including the accumulator.   2. The fluid circuit control device comprising the accumulator according to claim 1, wherein the controller and the flow rate control means of the fluid pressure pump are connected by an electric signal line, and the discharge flow rate from the accumulator and the fluid pressure pump are A fluid circuit control device equipped with an accumulator, wherein the total discharge amount of the discharge amount can be controlled to be constant by the controller.

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