WO1998036197A1 - Pressure compensating valve and directional control valve system using it - Google Patents

Abstract

A pressure compensating valve comprises a valve body (1); a fitting hole (5) having an inlet port (2) and an actuator port (3), a fitting body (6) fitted to the fitting hole; a piston (7) inserted into a hole (10) of the fitting body and defining a second pressure chamber (15); and a check valve (8) so structured as to be pushed in the valve opening direction by the pressure from the inlet port and in the valve closing direction by the hydraulic pressure in the second pressure chamber via the piston, for establishing or intercepting communication of the inlet port with the actuator port. A maximum load pressure is supplied to the second pressure chamber. A directional control valve system using such a pressure compensating valve is also disclosed.

Description

 TECHNICAL FIELD A pressure compensating valve and a directional control valve device using the same

 TECHNICAL FIELD The present invention relates to a directional control valve device for supplying hydraulic pressure discharged from a hydraulic pump to a hydraulic actuator, and a pressure compensating valve used for the same.

 Background art

 A pressure compensating valve is provided in the circuit connecting each directional control valve and each hydraulic actuator, and this pressure compensating valve is pushed in the direction of the opening area by the pump discharge pressure, and is the highest at the load pressure of each hydraulic actuator. A directional control valve device is known which is configured to be pressed in a small opening area direction by a load pressure (hereinafter referred to as a maximum load pressure) and to supply hydraulic pressure discharged from a hydraulic pump to a plurality of hydraulic factories having different load pressures. .

 In this type of directional control valve device, the pressure compensating valve is incorporated in the valve body of the directional control valve. However, since the structure of the conventional pressure compensating valve is complicated, the assembling work is very troublesome.

 Therefore, an object of the present invention is to provide a pressure compensating valve and a directional control valve device using the same, which can solve the above-mentioned problems. Disclosure of the invention

 A first aspect of the present invention for achieving the above object is as follows.

A valve body,

Inflow port and actuator, formed in the valve body A mounting hole having a port,

 An attachment body fitted to the attachment body,

 A piston which is inserted into a hole of the mounting body to define a second pressure chamber, and which is pushed in a valve-opening direction by the pressure of the inflow port, and which is pressed by the hydraulic pressure in the second pressure chamber. A check valve configured to be pushed in the valve closing direction via a piston and communicating and blocking the inflow port and the actuator port;

 A pressure compensating valve adapted to supply a maximum load pressure to the second pressure chamber.

 According to the first aspect, since the pressure compensating valve is formed by the mounting body, the piston, and the check valve, the structure is simplified, and the mounting body is mounted by being inserted into the mounting hole of the valve body. It can be easily installed.

 A second aspect of the present invention provides:

 A valve body,

 A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuator port;

 An attachment body fitted to the attachment body,

 A piston which is inserted into the hole of the mounting body to define a first pressure chamber and a second pressure chamber;

 The third pressure chamber is slidably fitted to the piston to define a third pressure chamber. The third pressure chamber is pushed in the valve opening direction by the pressure of the inflow port, and the screw is pressed by the hydraulic pressure in the second pressure chamber. A check valve configured to be pushed in a valve closing direction through a ton, and that communicates with the inflow port and the actuator port;

The check valve is formed on the check valve, and the check valve is in a communication direction. Pores communicating the third pressure chamber with the actuator port when moved to

 A first oil hole formed in the piston and communicating the first pressure chamber with the third pressure chamber;

 A second oil hole formed in the valve body and communicating the inflow port with the first pressure chamber;

 A first throttle and a second throttle provided in the second oil hole, supplying a maximum load pressure to the second pressure chamber, and detecting a load pressure from between the first throttle and the second throttle; Pressure compensating valve. According to the second aspect, when the check valve communicates between the inflow port and the actuator port, the flow of pressurized oil occurs between the inflow port and the actuator port. The pressure between the throttle and the second throttle is an intermediate pressure between the pressure of the inflow port and the pressure of the actuator port.

 Because of this, a pressure intermediate between the pump pressure and the load pressure can be detected as the load pressure, and the pressure compensating valve can be controlled with high accuracy using the intermediate pressure. A third aspect of the present invention,

 A valve body,

 A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuating port;

 An attachment body fitted to the attachment body,

 A piston which is inserted into a hole of the mounting body to define a first pressure chamber and a second pressure chamber;

The third pressure chamber is slidably fitted to the piston to define a third pressure chamber. The third pressure chamber is pushed in the valve opening direction by the pressure of the inflow port, and the screw is pressed by the hydraulic pressure in the second pressure chamber. To be pushed in the valve closing direction via the ton A check valve for communicating and shutting off the inflow port and the actuating port;

 A pore formed in the check valve and communicating the third pressure chamber to the actuating port when the check valve moves in the communication direction;

 A first oil hole formed in the piston and communicating the first pressure chamber with the third pressure chamber;

 A second oil hole formed in the valve body and communicating the inflow port with the first pressure chamber;

 A first throttle and a second throttle provided in the second oil hole, for supplying a maximum load pressure to the second pressure chamber, and applying a load from a downstream side of the second oil hole from the second throttle. This is a pressure compensating valve that detects pressure.

 According to the third aspect, the same operation and effect as those of the second aspect can be obtained.

 A fourth aspect of the present invention provides:

 A valve body,

 A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuating port;

 An attachment body fitted to the attachment body,

 A piston which is inserted into a hole of the mounting body to define a second pressure chamber, and a cylinder provided in the mounting body and pressing the piston,

It is pushed in the valve opening direction by the pressure of the inflow port, and is pushed in the valve closing direction via the piston by the oil pressure in the second pressure chamber. A check valve that is closed by the cylinder section via the piston, and communicates and shuts off the inflow port and the actuator port. When,

 Switching means for switchingly connecting the cylinder chamber of the cylinder section to one of the inflow port and the tank;

 The pressure compensating valve is configured to supply a maximum load pressure to the second pressure chamber.

 According to the fourth aspect, since the mounting body, the piston, the check valve, and the cylinder are pressure-compensating valves, the structure is simplified, and the mounting body is connected to the mounting hole of the valve body. It can be easily installed because it only has to be inserted into the device.

 Also, if the cylinder chamber of the cylinder section communicates with the tank, the cylinder section does not apply a pressing force to the piston, so that it functions as a pressure compensating valve.

 On the other hand, if the cylinder chamber of the cylinder communicates with the inflow port, the cylinder presses the piston to hold the check valve in the shut-off position. Function, and the connection between the inflow port and the actuarial port is always shut off.

 In this way, the pressure oil at the inflow port is supplied to the actuating port while compensating the pressure, or the pressure oil at the inflow port is actuated regardless of the pressure at the inflow port. Since it cannot be supplied to one tap, the pressure compensating valve has a directional control function.

 According to a fifth aspect of the present invention,

 A valve body,

The inlet port and the actuator are formed on the valve body. A mounting hole having a port,

 An attachment body fitted to the attachment body,

 A free piston which is inserted into the hole of the mounting body to form a fourth pressure receiving chamber,

 A piston which is inserted into the hole of the free piston and the hole of the mounting body to define a first pressure chamber and a second pressure chamber;

 The third pressure chamber is slidably fitted to the piston to define a third pressure chamber. The third pressure chamber is pushed in the valve opening direction by the pressure of the inflow port, and the piston is pressed by the hydraulic pressure in the second pressure chamber. The valve is pushed in the valve closing direction via the tongue, and is closed via the free piston and the piston by the hydraulic pressure in the fourth pressure receiving chamber. A check valve for communicating with and shutting off the inflow port and the actuating port;

 A pore formed in the check valve, the pore communicating the third pressure chamber with the actuator port when the check valve moves in the communication direction;

 A first oil hole formed in the piston and communicating the first pressure chamber with the third pressure chamber;

 A second oil hole formed in the valve body and communicating the inflow port with the first pressure chamber;

A first throttle and a second throttle provided in the second oil hole, supplying a maximum load pressure to the second pressure chamber, and detecting a load pressure from between the first throttle and the second throttle; Pressure compensating valve. According to the fifth aspect, since the pressure compensating valve is formed by the mounting body, the piston, the check valve, and the free piston, the structure is simplified, and the mounting body is provided in the mounting hole of the valve body. Easy installation because it only needs to be inserted and mounted Can be.

 In addition, if the fourth pressure chamber communicates with the tank, the free piston does not apply a pressing force to the piston 7, so that it functions as a pressure compensating valve. On the other hand, if the fourth pressure chamber is connected to the inflow port, the free piston pushes the piston and holds the check valve in the shut-off position, so that it does not function as a pressure compensating valve. The connection between the inflow port and the factory port is always shut off.

 In this way, the pressure oil of the inflow port is supplied to the actuator port while compensating the pressure, or the pressure oil of the inflow port is supplied to the actuator port irrespective of the pressure of the inflow port. Since it is possible not to supply to port 3, a pressure compensating valve having a directional control function is obtained.

 Also, when the check valve communicates the inflow port with the actuating port, pressure oil flows between the outflow port and the actuating port, and the pressure of the outflow port and the actuating port. The pressure in the middle of the pressure is detected as the load pressure.

 Thus, a pressure intermediate between the pump pressure and the load pressure can be detected as the load pressure.

 A sixth aspect of the present invention is a pressure compensating valve according to the third aspect, wherein the first throttle is a variable throttle.

 According to the sixth aspect, since the pressure in the first pressure chamber changes by changing the size of the first throttle, the force for pushing the check valve to the shutoff position with the screw changes. .

 Thus, the pressure compensation characteristic of the pressure compensation valve can be made variable.

A seventh aspect of the present invention is a method according to the second, third or fifth aspect, wherein This is a pressure compensating valve that connects the middle of the first throttle and the second throttle to a drain path having a third throttle.

 According to the seventh aspect, a part of the pressure oil at the inflow port flows out to the tank, and the pressure at the in-take port does not rise rapidly, but the pressure at the factory port also rises rapidly. do not do. That is, it has a bleed-off function.

 Because of this, the hydraulic actuator that operates at the pressure of the actuator port does not suddenly start operating.

 An eighth aspect is the method according to any of the above aspects,

 A relief port opening to the mounting hole;

 A check valve for a relief valve that permits the flow of pressurized oil from the actuator port to the relief port,

 A pressure compensating valve in which the relief port is connected to a relief valve.

 According to the eighth aspect, the pressurized oil in the work overnight port flows from the check valve for the relief valve and the relief port to the relief valve.

 Therefore, the pressure relief valve can be used to prevent abnormal pressure at the actuating port, and a relief valve can be used for one or more pressure compensation valves. It becomes possible.

 A ninth aspect of the present invention is a

 A valve body,

It has a main spool hole in which the outlet port, the first pump port, and the second pump port are open, and a main spool inserted in the main spool hole. The ports are shut off when the main spool is in the neutral position, and when the main spool is in the first position, which is closer to the neutral position, and in the other position. R A main flow control valve configured such that the ports communicate with each other when the port moves to the second position,

 A first pressure compensating valve for pressure-compensating the pressure oil at the outlet port and supplying it to the first actuator port;

 A second pressure compensating valve for pressure-compensating the pressure oil at the outlet port and supplying it to a second actuator port;

 A meter flow control valve for switching one of the first actuating port and the second actuating port to the tank port;

 Wherein the first pressure compensating valve is

 A mounting hole formed in the valve main body, the mounting port being open to the outlet port and the first actuator port;

 An attachment body fitted to the attachment body,

 A piston which is inserted into a hole of the mounting body to define a second pressure chamber, and a cylinder provided in the mounting body and pressing the piston.

 It is pushed in the valve opening direction by the pressure of the outlet port, is pushed in the valve closing direction via the piston by the oil pressure in the second pressure chamber, and the piston part is pushed by the cylinder part. A check valve for closing the communication port between the outlet port and the first actuating port.

 The second pressure chamber is configured to supply a maximum load pressure to the second pressure chamber, and the second pressure compensating valve includes:

A mounting hole formed in the valve main body, wherein the outlet port and the second actuator port are opened; An attachment body fitted to the attachment body,

 A piston which is inserted into a hole of the mounting body to define a second pressure chamber, and a cylinder provided in the mounting body and pressing the piston;

 It is pushed in the valve opening direction by the pressure of the outlet port, is pushed in the valve closing direction via the piston by the oil pressure in the second pressure chamber, and is pushed by the cylinder part. A check valve for closing the outlet port and the second actuator port, the check valve being adapted to be closed via the piston;

 A maximum load pressure is supplied to the second pressure chamber, and when the mating spool is at the first position, the cylinder of the cylinder portion of the first pressure compensating valve is provided. A chamber communicates with the outlet port, and a cylinder chamber of a cylinder portion of the second pressure compensating valve communicates with the tank;

 When the mating spool is at the second position, the cylinder chamber of the cylinder part of the second pressure compensating valve communicates with the outlet port and the cylinder of the first pressure compensating valve. This is a directional control valve device that allows the cylinder chamber of the cylinder part to communicate with the tank.

According to the ninth aspect, by setting the metering spool to the first position, the first pressure compensating valve is closed and the second pressure compensating valve is pressure compensated. By connecting the first actuator port of the meter-out flow control valve to the tank port, the pressure oil flowing into the first and second pump ports is discharged to the second pressure compensating valve. From this, it is supplied to the second actuating port, and the pressure oil of the first actuating port flows out to the tank port. By setting the mating spool to the second position, the second pressure compensating valve is closed and the first pressure compensating valve is pressure compensated. By connecting the second actuator port of the meter flow control valve to the tank port, the pressure oil flowing into the first and second pump ports flows from the first pressure compensating valve. The oil is supplied to the 1st factory overnight port, and the pressurized oil of the 2nd factory port flows out to the tank port.

 Because of this, the pressure oil that has flowed into the first and second pump ports can be supplied to the first or second actuating port with pressure compensation, and the second or first pump can be supplied. Since the pressure oil at the port of the hydraulic pump can be drained to the tank, the hydraulic oil can be supplied to the first and second chambers of the hydraulic actuator.

 In addition, by moving the spool for mating to one or the other, the first pump port and the second pump port communicate with the outlet port, so the pressure flowing into the two pump ports is reduced. Oil spills to one outlet port.

 As a result, a flow rate twice as large as the diameter of the spool can be supplied to the outlet port, so that the diameter of the metering spool can be reduced accordingly and the device can be made compact.

 A tenth aspect of the present invention is the ninth aspect, wherein

The outlet port is provided when the above-mentioned mating spool is at the first position and the check valve is moved in the communication direction across the above-mentioned mating spool and the above-mentioned first pressure compensating valve. A first communication passage communicating the first actuator port with the first actuator port via a plurality of throttles, and a first communication passage from a plurality of throttles in the first communication passage. Detects the load pressure at the cut-out port, The outlet port is connected to the outlet port when the check spool is in the second position and the check valve moves in the communication direction, over the mating spool and the second pressure compensating valve. A second communication path is provided to communicate the second actuator port via a plurality of throttles, and a load pressure of the second actuator port is defined between the plurality of throttles in the second communication path. This is a directional control valve device that detects the pressure.

 According to the tenth aspect, an intermediate pressure between the pump pressure and the load pressure can be detected as the load pressure.

 The eleventh aspect is the ninth or tenth aspect, wherein

 The first and second pressure compensating valves have another pressure chamber between the cylinder portion and the piston, and the hydraulic pressure in the other pressure chamber passes through the piston via the piston. Pressure valve in the valve closing direction, and the pressure chamber of the first pressure compensating valve and the outlet port communicate with each other via the variable throttle mechanism when the main spool is in the second position. A direction control valve device wherein the pressure chamber of the second pressure compensating valve and the outlet port communicate with each other through another variable throttle mechanism when the mating spool is at the first position.

 According to the eleventh aspect, the force of the piston pressing the check valve can be changed by changing the size of the throttle of the variable throttle mechanism, so that the pressure compensation characteristic of the pressure compensation valve can be varied.

 A 12th embodiment is the 10th embodiment,

A directional control valve device, wherein each of the variable throttle mechanisms has a configuration in which the throttle is variable by hydraulic pressure in the pressure receiving chamber, and a means for supplying pressure oil to the pressure receiving chamber is provided. According to the first and second configurations, the pressure compensation characteristic can be varied by controlling the pressure oil supply means and changing the output pressure. The pressure compensation characteristics can be set arbitrarily by controlling with a controller.

 BRIEF DESCRIPTION OF THE FIGURES

 The invention will be better understood from the following detailed description and the accompanying drawings, which show embodiments of the invention. The embodiments shown in the accompanying drawings are not intended to specify the invention, but merely to facilitate explanation and understanding.

 In the figure,

 FIG. 1 is a sectional view showing a first embodiment of a pressure compensating valve according to the present invention.

 FIG. 2 is a sectional view showing a pressure compensating valve according to a second embodiment of the present invention.

 FIG. 3 is a sectional view showing a third embodiment of the pressure compensating valve according to the present invention.

 FIG. 4 is a cross-sectional view of one embodiment of a directional control valve device using a pressure compensating valve.

 FIG. 5 is an enlarged sectional view of the main flow control valve and the first and second pressure compensating valves of the directional control valve device.

 FIG. 6 is a sectional view taken along line VI-VI of FIG.

 FIG. 7 is a sectional view taken along line W—YE of FIG.

 FIG. 8 is an operation explanatory diagram when the mating spool and the metering spool of the directional control valve device are at the first position.

Fig. 9 shows the mating spool and meter for the directional control valve device. FIG. 7 is an explanatory diagram of the operation when the art spool is in a second position.

 FIG. 10 is an enlarged sectional view of a pilot switching valve portion of the directional control valve device.

 FIG. 11 is a sectional view showing another embodiment of the directional control valve device provided with a variable throttle function.

 FIG. 12 is an explanatory diagram showing another example of the pilot switching valve. BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, a pressure compensating valve and a directional control valve device according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

 First, a first embodiment will be described.

 As shown in FIG. 1, the valve body 1 is formed with an oil through hole 4 that communicates between an inflow port 2 into which the discharge pressure oil of the hydraulic pump flows and an actuating port 3. A mounting hole 5 is formed coaxially with the oil through hole 4. In the mounting hole 5, an actuator port 3, a pump pressure supply port 20, a high load pressure inflow port 21, and a relief port are provided. The pressure compensating valve is composed of a mounting body 6, a screw 7, a check valve 8, and the like, which is open and has a fitting 31 fitted into and fixed to the mounting hole 5.

 That is, a small-diameter hole 9 and a large-diameter hole 10 are formed coaxially and continuously in the mounting body 6 to form a stepped hole. The piston 7 is a stepped piston in which a large diameter piston 11 and first and second small diameter pistons 12 and 13 are formed coaxially and continuously.

The first small-diameter piston 12 fits into the small-diameter hole 9 to define the first pressure chamber 14, and the large-diameter piston 11 fits into the large-diameter hole 10 to form the second pressure chamber 14. 15 is defined. The second small-diameter piston 13 is fitted in the hole 16 of the check valve 8 fitted in the oil passage 4 to define a third pressure chamber 17. The piston 7 is pushed rightward by a spring 18 housed in the first pressure chamber 4 so that the first small-diameter piston 13 passes through the check valve 8 through the oil through hole. 4. The diameter of the sheet 19 is larger than the diameter of the large-diameter piston 11 in pressure contact with the opening edge (sheet 19) of 4.

 The first pressure chamber 14 communicates with a pump pressure supply port 20 and the second pressure chamber 15 communicates with a maximum load pressure inflow port 21. The third pressure chamber 17 has a fine hole (throttle) 22 and opens to the outer peripheral portion of the port valve 8 at a position closer to the inflow port 2 than the sheet pressure contact portion. The pores 22 are shut off when the port 8 is shutting off the intake port 3 and the inflow port 2. The first pressure chamber 14 and the third pressure chamber 17 communicate with each other via an oil hole 23 formed in the central shaft of the screw 7. The pump pressure supply port 20 communicates with the inflow port 2 through an oil hole 26 having a first throttle 24 and a second throttle 25, and this oil hole 26 is the highest through a check valve 27. Connected to load pressure detection circuit 28. A portion of the oil hole 26 between the first throttle 24 and the second throttle 25 is connected to a drain path 30 having a throttle 29.

 An oil hole 26 of another pressure compensating valve (not shown) is connected to the maximum load pressure detecting circuit 28 via a check 27, and the highest load pressure is detected in the circuit 28. Is done.

A cylindrical valve 32 is slidably fitted between the inner peripheral surface of the mounting hole 5 and the outer peripheral surface of the small diameter portion of the mounting body 6, and the cylindrical valve 32 is sealed with a spring 33. By pressing against port 3 4, the actuator port 3 and the relief port 31 are shut off, and the hydraulic pressure in the actuator port 3 is applied. When the cylindrical valve 32 is piled on the spring 33 and pushed to the left in FIG. 1, the actuator port 3 and the relief port 31 communicate. Thus, a check valve 35 for relief is constituted.

 The piston 7 is pushed to the right (in the direction in which the valve 8 is pressed against the sheet 19) at the highest load pressure flowing into the spring 18 and the second pressure chamber 15 and the port valve is pressed. 8 is pushed to the left (in the direction away from sheet 19) by the inflow port 2 pump pressure.

 Since the pressure receiving area of the second pressure chamber 15 is smaller than the pressure receiving area of the port valve 8, the port valve 8 is pushed to the left by the pump pressure to open, and is connected to the inflow port 2 Actuator port 3 communicates.

 As a result, the inflow port 2, the oil hole 26, the pump pressure supply port 20, the first pressure chamber 14, the oil hole 23, the third pressure chamber 17 and the pore 22 2 (3) communicates with the pressure oil, so that the intermediate pressure between the pump pressure and the load pressure acts on the upstream side of the check valve (27) as the load pressure, and the load pressure becomes the maximum load pressure detection circuit (28). Will be introduced.

 In this way, by detecting the pressure intermediate between the pump pressure and the load pressure as the load pressure, the maximum load pressure becomes higher than the actual maximum load pressure, so that the opening degree of the port valve 8 ( The opening area of the inlet port 2 and the opening port of the factory port 3) is small, and the flow can be distributed with high accuracy.

 Also, a part of the pressure oil in the oil hole 26 flows out of the drain passage 30 through the throttle 29 to the tank, so that a bleed-off function occurs.

Also, the pressure oil of the actuator port 3 pushes the cylindrical valve 32 to the left, flows from the relief port 31 to the relief valve 36, and the relief valve When the pressure becomes higher than the set pressure of 36, the relief valve 36 operates. W

17

 Also, when the cylindrical valve 32 is pressed against the sheet 34 by the pressurized oil of the relief port 31 and the spring 33, the actuator port 3 and the relief port 31 are connected. Since it is shut off, the pressurized oil of the relief port 31 does not flow to the actuator port 3.

 5 Because of this, the abnormal high pressure of a plurality of factory ports 3 can be prevented by one relief valve 36.

 FIG. 2 shows a second embodiment.

 In this case, a hole is provided in the oil hole 23 of the piston 7 to form a second throttle 25, and a load pressure detection is detected from the port 37 and the oil hole 38 in the middle of the oil hole 23. It communicates with oil hole 39. The load pressure detection oil hole 39 communicates with the maximum load pressure detection circuit 28 with the check valve 27 and also communicates with the drain path 29.

 The first aperture 24 is a variable aperture. By adjusting the throttle (opening area) of the first throttle 24, the pressure in the first pressure chamber 14 changes, so that the pressure compensation characteristic can be made variable.

 Next, a third embodiment will be described.

 As shown in FIG. 3, the flip-flop 41 is inserted into the hole 40 of the mounting body 6 to define the fourth pressure chamber 42. The first small diameter piston 12 of the piston 7 is fitted into the hole 43 of the free piston 41 to define the first pressure 20 power chamber 14. The large-diameter piston 11 of the piston 7 is fitted into the hole 40 to define the second pressure chamber 15 between the free piston 41 and the piston 7. The cylinder section A presses the valve against the check valve 8 to form a cylinder section A, and the fourth pressure receiving chamber 42 becomes a cylinder chamber of the cylinder section A.

25 For control, the valve body 1 communicates with the fourth pressure chamber 42 via the oil hole 6a. A port 44 is formed, and the control port 44 is switched to one of the inflow port 2 and the evening port. For example, by switching the position of the spool of the directional control valve described later, communication with the inflow port 2 or communication with the tank port is made.

 Therefore, when the control port 44 communicates with the inflow port 2 to supply pump pressure to the fourth pressure receiving chamber 42, the free piston 41 moves to the right. And push piston 7 to the right to hold port valve 8 in the shut-off position. As a result, the check valve 8 does not move in the communication direction due to the pump pressure of the inflow port 2.

 If the control port 44 communicates with the tank, the fourth pressure chamber 42 becomes the tank pressure, and the free piston 41 is pushed to the left by the spring 18 so that the piston is pushed. Separated from large diameter piston 11 of pin 7. Thereby, it operates similarly to the above-mentioned pressure compensating valve.

 Next, a directional control valve device using a pressure compensating valve will be described. As shown in FIG. 4, a directional control valve device is composed of the main flow control valve 45, the first pressure compensating valve 46, the second pressure compensating valve 47, and the meter flow control valve 48. ing.

 Next, the specific structure of each valve will be described.

 (Main flow control valve)

As shown in FIGS. 4 and 5, a valve spool 50 is formed in the valve body 50, and an outlet port 52 is formed in the valve spool 51. . In addition, the first pump port 53, the first pilot port 54, and the first tank port are located on the left side of the main spool hole 51, with the outlet port 52. 5 5, 1st load pressure port 56 is formed, and 2nd bottle is located on the right side of outlet port 52 A port 57, a second pilot port 58, a second tank port 59, and a second load pressure port 60 are formed, respectively.

 The fitting spool 61 inserted into the fitting spool hole 51 is held at the neutral position by the spring 62, and the pressurized oil is supplied to the first pressure receiving chamber 63. Then, when the pressure oil is supplied to the second pressure receiving chamber 64, it moves to the left to the second position. Pressurized oil is supplied to the first pressure receiving chamber 63 by a first electromagnetic proportional pressure control valve 65 for mating control. The first electromagnetic proportional pressure control valve 65 communicates and shuts off the inlet port 66 and the outlet port 67 as shown in FIG. 10, and the valve 68 is set to the shut-off position. Consists of a spring 69 and a proportional solenoid 70 that presses the valve 67 in the communication direction, and outputs a pressure proportional to the amount of electricity to the proportional solenoid 70 to the outlet port 67. . The outlet port 67 communicates with the first pressure receiving chamber 63.

 Pressurized oil is supplied to the second pressure receiving chamber 64 by a second electric proportional pressure control valve 71 for mating control. The second electromagnetic proportional pressure control valve 71 has the same structure as the first electromagnetic proportional pressure control valve 65, and its outlet port 67 communicates with the second pressure receiving chamber 64.

The main spool 61 is provided with a first 'second main slit groove for communicating and blocking between the first and second pump ports 53, 57 and the outlet port 52, respectively. The pair of 72 and 73 and the pair of third and fourth main slot grooves 74 and 75 are shifted in the circumferential and axial directions as shown in Figs. 6 and 7. It is formed. Further, the first main slit groove 72 and the second main slit groove 73 are displaced in the axial direction. Also, the third main slit groove 74 and the fourth slit groove 75 are not positioned in the axial direction. Have been.

 When the sewing spool 61 is in the neutral position shown in FIG. 4, the first pump port 53, the second pump port 57, and the outlet port 52 are shut off. When the mating spool 61 is in the first position shown in FIG. 8, the first pump port 53 and the outlet port 52 communicate with the first main slit groove 72, and the second The second pump port 57 and the outlet port 52 communicate with each other through the main slit groove 73. When the spool for mating 61 is in the second position shown in FIG. 9, the first main slit groove 74 connects the first pump port 53 and the outlet port 52 to each other. The second pump port 57 and the outlet port 52 communicate with each other through the fourth main slit groove 75.

 In this way, the main spool 61 moves to the first position and the second position, so that the first pump port 53 and the second pump port 57 communicate with the outlet port 52. Therefore, a flow rate twice as large as that of a normal valve having the same stroke can flow to the outlet port 52 as the diameter of the main spool 61.

 Also, as shown in FIG. 4, the discharge path 76 a of the first hydraulic pump 76 is connected to the first pump port 53, and the second hydraulic pump 7 is connected to the second pump port 57. By connecting the discharge passage 77 a of FIG. 7, the discharge pressure oils of the first and second hydraulic pumps 76 and 77 can be combined and supplied to the outlet port 52. The first and second pump ports 53, 57 may be supplied with the discharge pressure oil of one hydraulic pump.

As shown in FIG. 5, the mating spool 61 has a first position. A slit groove 78 for the pilot and a slit groove 79 for the second pilot are formed. The spool for mating 61 is the middle spool shown in Figs. 4 and 5. When in the upright position, the first pilot slit groove 78 communicates the first pump port 53 and the first pilot port 54 and the second pilot slot. The lit groove 79 communicates the second pump port 57 and the second pilot port 58.

 When the main spool 61 is in the first position shown in FIG. 8, the first pilot slit groove 78 is connected to the first bom port 53 and the first pilot port. The second pilot slot groove 79 communicates the second pilot port 58 and the second tank port 59.

 When the main spool 61 is in the second position shown in FIG. 9, the first pilot slit groove 78 is connected to the first pilot port 54 and the first tank port 5. 5 and the second pilot slit groove 79 communicates the second pump port 57 and the second pilot port 58.

 As shown in FIG. 5, a first oil hole 80 and a second oil hole 81 are formed on the main spool 61. The first oil hole 80 opens at the outer peripheral surface near the second oil hole 81 at the first drill hole 82 and opens at the outer peripheral surface near one end at the second drill hole 83. The second oil hole 81 opens at the outer peripheral surface from the first oil hole 80 at the third drill hole 84, and opens at the outer peripheral surface near the other end at the fourth drill hole 85.

When the mating spool 61 is in the neutral position shown in FIGS. 4 and 5, the first oil hole 80 opens to the first load pressure port 56 through the second drill hole 83 and the first oil hole 80 opens. The drill hole 82 is closed. Further, the second oil hole 81 opens to the second load pressure port 60 at the fourth drill hole δ5, and the third drill hole 84 is closed. When the mating spool 61 is in the first position shown in FIG. 8, the first oil hole 80 is in the second drill hole 83 and the first tank port 55 and the first load pressure port 56 And the first drill hole 82 is closed. Further, the second oil hole 81 opens at the outlet port 52 at the third drill hole 84 and opens at the second load pressure port 60 at the fourth drill hole 85.

 When the mating spool 61 is at the second position shown in FIG. 9, the second oil hole 81 is connected to the second tank port 59 and the second load pressure port 60 at the fourth drill hole 85. It is open and the third drill hole 84 is closed. Further, the first oil hole 80 opens to the outlet port 52 at the first drill hole 82 and opens to the first load pressure port 56 at the second drill hole 85.

 The first spool 61 has a first drain slit groove 86 and a second drain slit groove 87, and the first spool 61 has the first drain slit groove 87. When moving from the neutral position to the first position, the second load pressure port 60 communicates with the second tank port 59 at the second drain slit 87, and the stroke When it moves to, the connection between the second load pressure port 60 and the second tank port 59 is shut off.

 When the main spool 61 moves from the neutral position to the second position, the first load pressure port 56 becomes the first tank port 5 through the first drain slit groove 86. The first tank port 55 shuts off to the first load pressure port 56 when it moves to the stroke. The first and second load pressure ports 56 and 60 are connected to a maximum load pressure detection path 89 via a check valve 88.

 (1st pressure compensating valve)

As shown in FIG. 5, the first pressure compensating valve 46 has the same structure as the above-described pressure compensating valve shown in FIG. 3, and has the outlet port 52 and the first Communication with Chiyue overnight port 90. The fourth pressure chamber 42 communicates with the first pilot port 54 at the first oil hole 91, and the first pressure chamber 14 communicates with the first load pressure port 56 at the second oil hole 92. Communicating.

 (2nd pressure compensating valve)

 As shown in FIG. 5, the second pressure compensating valve 46 has the same structure as the above-described pressure compensating valve shown in FIG. 3, and has an outlet port 52 and a second actuator port 9. Connect and cut off 3. The fourth pressure chamber 42 communicates with the second pilot port 58 through the third oil hole 94, and the first pressure chamber 14 communicates with the second load pressure port 60 through the fourth oil hole 95. Communicating.

 (Meter port flow control valve)

 As shown in FIG. 4, a tank port 101, a first actuator port 102, and a second actuator are provided in a valve spool 100 of the valve body 50 in a meter spool hole 100. An overnight port 103 is formed (a meter spool 104 fitted to the meter spool 104 is composed of the first spring 105 and the second spring 105). It is held at the neutral position by the spring 106, and when pressurized oil is supplied to the first pressure receiving chamber 107, it moves to the right as shown in Fig. 8 to be the first position, and the second pressure receiving chamber When the pressurized oil is supplied to 108, it moves to the left as shown in Fig. 9 and becomes the second position.

Each port is shut off when the spool 104 is in the neutral position. When the motor-out spool 104 is in the first position, the first actuator port 102 communicates with the tank port 101. When the meter spool 104 is in the second position, the second actuator overnight port 103 communicates with the tank port 101. As shown in FIG. 10, the third solenoid proportional pressure control valve 110 for the meter-out includes a spool 113 that communicates and shuts off the inlet port 111 and the outlet port 112. Spring 1 1 4 holding spool 1 1 3 in position to block inlet port 1 1 1 and outlet port 1 1 2 and spool 1 1 3 in inlet port 1 1 1 and outlet port 1 1 2 It is composed of a nozzle 115 that pushes to the position where the communicates.

 The pressure oil in the outlet port 112 is switched and supplied to one of the first pressure receiving chamber 107 and the second pressure receiving chamber 108 by a pilot switching valve 116. As shown in FIG. 10, the pilot switching valve 1 16 includes a first spool 1 17 and a second spool 1 18, and the first spool 1 1 7 at the spring 1 19. To the first position to connect the inflow port 122 to the first outflow port 122 and the second outflow port 123 to the tank port. At this time, the second spool 118 is pushed by the first spool 117 and moves. The second spool 1 18 is pushed by the pressure oil in the pressure chamber 124 and the first spool 1 17 is set to the second position, and the inflow port 121 is connected to the second outflow port 123. The first outflow port 122 is connected to the tank port.

 The inflow port 1 2 1 communicates with the outlet port 1 1 2, the first outflow port 1 2 2 communicates with the second pressure receiving chamber 1 0 8, and the second outflow port 1 2 3 communicates with the 2 1 The pressure receiving chamber 107 is connected to the pressure receiving chamber 107, and the pressure chamber 124 is connected to the fourth pressure chamber 42 of the first pressure compensating valve 46, that is, the first pilot port 54.

The electromagnetic proportional pressure control valves 65, 110, 71 are respectively attached to a first cover 126 and a second cover 126 a attached to the valve body 50. The first spool 1 17 of the pilot switching valve 1 16 1 The cover 1 256 is fitted into a spool hole 127 of the valve body 126, and the second spool 118 is fitted to a spool hole 128 of the valve body 50.

 The first actuator port 102 is connected to the first chamber 127 a of the hydraulic actuator 127, and the first actuator port 103 is connected to the second chamber 122. Connected to 9b.

 Next, the operation of the direction control valve device will be described.

 (When the first electromagnetic pressure control valve 65 for the meter and the third electromagnetic pressure control valve 110 for the meter operate)

 As shown in FIG. 8, pressurized oil flows into the first pressure receiving chamber 63 of the mating flow rate control valve 45, and the mating spool 61 becomes the first position. No ,. The first spool 1 17 of the pilot valve 1 16 is in the second position with the pressurized oil in the pressure chamber 124, and the output pressure of the third electromagnetic pressure control valve 110 for meter-out. Oil flows from the second outflow port 123 into the first pressure receiving chamber 105 of the meter flow control valve 48, and the meter spool 104 becomes the first position.

 As a result, the first pressure compensating valve 46 is closed as described above. The fourth pressure chamber 42 of the second pressure compensating valve 47 has the third oil port 94 and the second pilot port 5. 8, the second pilot slit groove 79, the second tank port 59 communicates with the tank, the first pressure chamber 14 has the fourth oil hole 95, the second load The pressure port 60, the fourth drill hole 85, the second oil hole 81, and the third drill hole 84 communicate with the outlet port 52. As a result, the spring 41 moves in a direction away from the piston 7 by the spring 18, and the second pressure compensating valve 47 enters a pressure compensation state.

On the other hand, the first actuator port 102 of the meter-out flow control valve 48 communicates with the tank port 71. Therefore, the pressure oil at the outlet port 52 depresses the check valve 8 of the second pressure compensating valve 47 and moves away from the sheet 19, and the second actuator overnight port 93 and the second actuator From the hydraulic port 103 to the second chamber 1229b of the hydraulic actuator 1229, and the pressurized oil in the first chamber 1229a flows into the first hydraulic port 1 Outflow from 0 2 to tank port 10 1.

 As described above, when the pressure oil is supplied while compensating the pressure by the second pressure compensating valve 47, the outlet port 52 and the second actuator port 93 are connected to the third port as described above. Drill hole 84, 2nd oil hole 81, 4th drill hole 85, 2nd load pressure port 60, 4th oil hole 95, 1st pressure chamber 14, 4th oil hole 23, 3rd pressure It communicates with chamber 17 and pore 22.

 As a result, pressure oil flows between the outlet port 52 and the second reactor port 93, and as described above, the pressure of the second load pressure port 60 is reduced by the outlet port 52. It is an intermediate pressure between the pressure and the pressure of the second factor 93. Therefore, an intermediate pressure between the pump pressure and the load pressure can be detected as the load pressure.

 Also, when the main spool 61 starts moving from the neutral position to the first position, the second sunset port 59 and the second load pressure are moved through the second drain slit groove 87. Port 60 communicates, and a part of the pressure oil detected at the second load pressure port 60 flows out to the second tank port 59, so that the detected load pressure decreases and as described above. A bleed-off function occurs at the same time.

When the mating spool 61 moves the maximum stroke toward the first position, the second tank port 59 and the second load pressure port 60 are interrupted, and the load pressure becomes intermediate between the above. Pressure. (When the second electromagnetic proportional pressure control valve 71 for the main unit and the third electromagnetic proportional pressure control valve 110 for the main unit operate)

 As shown in FIG. 9, the pressurized oil flows into the second pressure receiving chamber 64 of the mating flow control valve 45, and the mating spool 61 becomes the second position. The first spool 1 18 of the pilot switching valve 1 16 is in the first position at the spring 1 19, and the output pressure oil of the electromagnetic pressure control valve 1 10 for meter-out is From the 1 outflow port 1 2 2 to the 2nd pressure receiving chamber 108 of the meter flow control valve 48, the metering spring 104 becomes the second position.

 As a result, the second pressure compensating valve 47 is closed as described above. C The fourth pressure chamber 42 of the first pressure compensating valve 46 is connected to the first oil hole 91 and the first pilot port 5. 4.The first pilot slit groove 78, the first tank port 55 communicates with the tank, and the free piston 41 is connected to the piston 7 by the spring 18 The first pressure compensating valve 46 moves in the direction away from the first pressure compensating valve 46, and the check valve 8 is opened by the pressurized oil.The first pressure chamber 14 has the second oil hole 92, the first load pressure port 5 6. The second drill hole 83, the first oil hole 80, and the second drill hole 82 communicate with the outlet port 52. As a result, the first pressure compensating valve 46 enters the pressure compensating state.

 On the other hand, the second actuator port 103 of the meter-out flow control valve 48 communicates with the tank port 101.

Therefore, the pressure oil at the outlet port 52 pushes the check valve 8 of the first pressure compensating valve 46 to release it from the sheet 19, and the hydraulic oil at the first actuating port 90 reaches the hydraulic actuating port 1 2 9 Flows into the first chamber 12 9a of the second chamber, and the pressurized oil in the second chamber 12 9b flows from the second actuator port 93 to the tank port from the second actuator port 103. From 1 101 Spills into tank.

 As described above, even when the pressure oil is supplied while the pressure is compensated by the first pressure compensating valve 46, the pressure between the outlet port 52 and the first actuating port 90 is the same as described above. Since the oil flows, the pressure between the pump pressure and the load pressure is detected at the first load pressure port 56 as the load pressure.

 Also, when the main spool 61 starts moving from the neutral position toward the second position, the first drain port 55 and the first load port are formed by the first drain slit groove 86. Since the pressure ports 56 communicate, the bleed-off function is generated as described above.

 FIG. 11 shows another embodiment of the directional control valve device. In this case, variable throttle mechanisms 130 are provided at both ends of the meter-in spool 61, respectively.

Specifically, in the variable throttle mechanism 13, a stepped hole 13 1 is formed continuously with the first oil hole 80, and a stepped piston 13 2 is formed in the stepped hole 13 1. An annular gap that is inserted and communicates between the first oil hole 80 and the second drill hole 83 is formed, that is, a variable throttle portion 133 and a pressure receiving chamber 134 are formed. The stepped piston 1332 is pushed in the direction in which the size of the throttle is increased by the spring 1335, and is pushed in the direction in which the size of the aperture is reduced by the pressure in the pressure receiving chamber 1334. However, the size of the throttle is inversely proportional to the pressure in the pressure receiving chamber 134. The pressure receiving chamber 134 communicates with a port 1337 through an oil hole 1336, and this port 1337 communicates with a pilot oil hole 1338 of the valve body 50. Pilot pressure oil is supplied to the pilot oil hole 1338 by a fourth electromagnetic proportional pressure control valve 1339 for variable pressure compensation. The fourth electromagnetic proportional pressure control valve 1339 has the same structure as the third electromagnetic proportional pressure control valve 110 for the meter, and its outlet port 112 is connected to the pilot oil. It communicates with hole 1 3 8.

 Thus, by supplying the output pressure of the fourth electromagnetic proportional pressure control valve 1339 to the pressure receiving chamber 133, the size of the restrictor of the variable restrictor 1333 changes. Since the pressure of the pressure oil flowing from the first oil hole 80 to the second drill hole 83 changes and the pressure supplied to the first pressure chamber 14 changes, the pressure compensation characteristic of the pressure compensating valve can be changed. can do. For example, when the output pressure is increased by increasing the amount of current supplied to the proportional solenoid 115, the pressure in the pressure receiving chamber 134 increases, and the diaphragm of the variable diaphragm section 133 increases (the opening area is smaller). As a result, the pressure in the first pressure chamber 14 decreases. As a result, the force for pushing the piston 7 is reduced, and the opening area between the outlet port 52 and the first actuator port 90 by the check valve 8 is increased, and the first pressure compensation is performed. The pressure compensation characteristic of valve 46 becomes weak.

 The variable throttle mechanism 130 provided on the second oil hole 81 side has the same structure as that provided on the first oil hole 80 side, and the pressure compensation characteristic of the second pressure compensating valve 47 is variable. And

 FIG. 12 shows another example of a pilot switching valve for switching the meter flow control valve 48. In this case, the first pilot switching valve 1 16 — 1 selectively communicates the first pressure receiving chamber 107 with one of the hydraulic pressure source and the tank, and the second pilot switching valve 11 1 In 6 — 2, the second pressure receiving chamber 108 is selectively connected to one of the hydraulic pressure source and the tank.

The first pilot switching valve 1 16-1 includes a first spool 15 3 for communicating / blocking the inflow port 150, the outflow port 15 1, and the tank port 15 2, The first spool 15 4 3 urges the first spool 15 3 to the first position, and the first spool 15 3 is pushed by the pressure of the pressure chamber 15 5. A second spool 1556 having a second position at the second position 153 is provided.

 The inflow port 150 communicates with the hydraulic pressure source, for example, the output side of the third solenoid proportional pressure control valve 110 for meterout, and the outflow port 1501 communicates with the first pressure receiving chamber 107. The pressure oil with the spool 61 of the mating flow control valve 45 in the first position is placed in the pressure chamber 15 5, for example, the pressure oil supplied to the fourth pressure receiving chamber 42 of the first pressure compensation valve 46. , Output hydraulic oil of the first electromagnetic proportional pressure control valve 65 for mating, output hydraulic oil of a switching valve that is switched by the output hydraulic oil of the first electromagnetic proportional pressure control valve 65, hydraulic pilot valve Output pressure oil or the like is supplied.

 The second pilot switching valve 1 16-2 has the same structure as the first pilot switching valve 1 16-1, and the inflow port 150 has a hydraulic source, for example, a solenoid for meter-out. The output side of the proportional pressure control valve 110 communicates with the output side, the outlet port 151 communicates with the second pressure receiving chamber 108, and the spool 61 of the meter-in flow control valve 45 connects to the pressure chamber 150. Hydraulic oil at the second position-for example, hydraulic oil supplied to the fourth pressure receiving chamber 42 of the second pressure compensating valve 47. Output hydraulic oil of the second electromagnetic proportional pressure control valve 71 for mating, (2) The output pressure oil of the switching valve switched by the output pressure oil of the electromagnetic proportional pressure control valve 71, the output pressure oil of the hydraulic pilot valve, etc. are supplied.

 Although the present invention has been described with reference to exemplary embodiments, various modifications, omissions, and additions may be made to the disclosed embodiments without departing from the spirit and scope of the present invention. It is obvious to those skilled in the art. Therefore, the present invention should not be limited to the above embodiments, but should be understood to include the scope defined by the elements recited in the claims and their equivalents.

Claims

The scope of the claims  1. The valve body,  A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuator port;  An attachment body fitted to the attachment body,  A piston which is inserted into a hole of the mounting body to define a second pressure chamber, and which is pushed in the valve opening direction by the pressure of the inflow port, and which is pressed by the oil pressure in the second pressure chamber. A check valve configured to be pushed in a valve closing direction via a valve, and for communicating and shutting off the inflow port and the actuator port;  A pressure compensating valve adapted to supply a maximum load pressure to the second pressure chamber. 2. The valve body and  A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuating port;  An attachment body fitted to the attachment body,  A screw which is inserted into the hole of the mounting body to define a first pressure chamber and a second pressure chamber;  The third pressure chamber is slidably fitted to the piston to define a third pressure chamber. The third pressure chamber is pushed in the valve opening direction by the pressure of the inflow port, and the screw is pressed by the hydraulic pressure in the second pressure chamber. A check valve that is pushed in the valve closing direction via a ton, and that communicates and shuts off the inflow port with the actuator port; The check valve is formed on the check valve, and the check valve is in a communication direction. Pores communicating the third pressure chamber with the actuator port when moved to  A first oil hole formed in the piston and communicating the first pressure chamber with the third pressure chamber;  A second oil hole formed in the valve body and communicating the inflow port with the first pressure chamber;  A first throttle and a second throttle provided in the second oil hole, for supplying a maximum load pressure to the second pressure chamber, and detecting a load pressure between the first throttle and the second throttle; Pressure compensating valve. 3. The valve body and  A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuating port;  An attachment body fitted to the attachment body,  A piston which is inserted into a hole of the mounting body to define a first pressure chamber and a second pressure chamber;  The third pressure chamber is slidably fitted to the piston to define a third pressure chamber. The third pressure chamber is pushed in the valve opening direction by the pressure of the inflow port, and the piston is pressed by the hydraulic pressure in the second pressure chamber. The valve is pushed in the valve closing direction via a ton, and communicates with the inflow port and the actuator port. • A check valve to shut off,  A pore formed in the check valve and communicating the third pressure chamber to the actuator port when the chin valve moves in the communication direction; The first pressure chamber formed in the piston is connected to the third pressure chamber. A first oil hole communicating with the chamber,  A second oil hole formed in the valve body and communicating the inflow port with the first pressure chamber;  A first throttle and a second throttle provided in the second oil hole, supplying a maximum load pressure to the second pressure chamber; (2) A pressure compensating valve that detects load pressure from downstream of the throttle. 4. Valve body,  A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuating port;  An attachment body fitted to the attachment body,  A piston which is inserted into a hole of the mounting body to define a second pressure chamber, and a cylinder provided in the mounting body and pressing the piston,  It is pushed in the valve opening direction by the pressure of the inflow port, is pushed in the valve closing direction by the oil pressure in the second pressure chamber via the piston, and the piston part is pushed by the cylinder part. A check valve configured to close and communicate between the inflow port and the actuator port;  Switching means for switchingly connecting the cylinder chamber of the cylinder portion to one of the inflow port and the tank;  A pressure compensating valve adapted to supply a maximum load pressure to the second pressure chamber. 5. Valve body and A mounting hole formed in the valve body, the mounting hole having an inflow port and an actuating port;  An attachment body fitted to the attachment body,  A free piston which is inserted into the hole of the mounting body to form a fourth pressure receiving chamber,  A piston which is inserted into the hole of the free piston and the hole of the mounting body to define a first pressure chamber and a second pressure chamber;  The third pressure chamber is slidably fitted to the piston to define a third pressure chamber. The third pressure chamber is pushed in the valve opening direction by the pressure of the inflow port, and the piston is pressed by the hydraulic pressure in the second pressure chamber. And the valve is closed via the free piston and the piston by hydraulic pressure in the fourth pressure receiving chamber. A check valve for communicating and shutting off the above-mentioned port,  A pore formed in the check valve and communicating the third pressure chamber to the actuator port when the check valve moves in the communication direction;  A first oil hole formed in the piston and communicating the first pressure chamber with the third pressure chamber;  A second oil hole formed in the valve body and communicating the inflow port with the first pressure chamber;  A first throttle and a second throttle provided in the second oil hole, for supplying a maximum load pressure to the second pressure chamber, and detecting a load pressure between the first throttle and the second throttle; Pressure compensating valve. 6. The pressure compensating valve according to claim 3, wherein the first throttle is a variable throttle. 7. The pressure compensating valve according to claim 2, 3 or 5, wherein an intermediate portion between the first throttle and the second throttle is connected to a drain path having a third throttle. 8. A relief port opening in the mounting hole,  A check valve for a relief valve that permits the flow of pressurized oil from the actuator port to the relief port,  The pressure compensating valve according to any one of claims 1 to 7, wherein the relief port is connected to a relief valve. 9. Valve body and  An outlet port, a first pump port, and a second pump port, each of which has an opening for a metering spool, and a spool for metering that is inserted into the spooling hole for the metering; When the main spool is in the neutral position, the ports are shut off, and when the main spool is moved from the neutral position to the first position closer to the one side and to the second position closer to the other side. A main flow control valve configured so that the ports communicate with each other;  A first pressure compensating valve for pressure-compensating the pressure oil at the outlet port and supplying it to the first actuator port;  A second pressure compensating valve for compensating the pressure oil at the outlet port and supplying it to the second actuator port;  A meter-out flow control valve for switching and communicating one of the first actuating port and the second actuating port to the tank port; Wherein the first pressure compensating valve comprises: A mounting hole formed in the valve body, wherein the outlet port and the first actuator port open;  An attachment body fitted to the attachment body,  A piston which is inserted into the hole of the mounting body to define a second pressure chamber, and a cylinder provided in the mounting body and pressing the piston.  It is pushed in the valve opening direction by the pressure of the outlet port, is pushed in the valve closing direction via the piston by the oil pressure in the second pressure chamber, and is pushed in the valve closing direction by the cylinder part via the piston. A check valve that communicates and shuts off the outlet port and the first actuator port;  The second pressure chamber is configured to supply a maximum load pressure to the second pressure chamber, and the second pressure compensating valve includes:  A mounting hole formed in the valve body, wherein the outlet port and the second actuator opening port are opened;  An attachment body fitted to the attachment body,  A piston which is inserted into a hole of the mounting body to define a second pressure chamber, and a cylinder provided in the mounting body and pressing the piston;  It is pushed in the valve opening direction by the pressure of the outlet port, is pushed in the valve closing direction via the piston by the oil pressure in the second pressure chamber, and the piston part is pushed by the cylinder part. And a check valve that communicates and shuts off the outlet port and the second actuator port. Supplying the maximum load pressure to the second pressure chamber, When the mating spool is at the first position, the cylinder chamber of the cylinder section of the first pressure compensating valve communicates with the outlet port and the cylinder section of the second pressure compensating valve. Of the cylinder rooms communicate with the evening  When the mating spool is at the second position, the cylinder chamber of the cylinder section of the second pressure compensating valve communicates with the outlet port and the cylinder section of the first pressure compensating valve. A directional control valve device in which the cylinder chamber of the tank communicates with the tank. 10. Between the main spool and the first pressure compensating valve-when the main spool is in the first position and the check valve moves in the communicating direction, A first communication path that connects the mouth port and the first actuator port via a plurality of throttles, and the first communication path is formed from a plurality of throttles in the first communication path. 1 Detect the load pressure of the actuator overnight port.  The outlet is provided when the main spool is in the second position over the main spool and the second pressure compensating valve and the check valve moves in the communication direction. A second communication path for communicating the port with the second actuator port through a plurality of throttles, and a second communication path from a plurality of throttles in the second communication path; The directional control valve device according to claim 9, wherein a load pressure of the cutout overnight port is detected. 11. The first and second pressure compensating valves have another pressure chamber between the cylinder part and the piston, and the pressure in the other pressure chamber makes the screw. The pressure valve and the outlet port of the first pressure compensating valve are pressed when the main spool is in the second position. The pressure chamber of the second pressure compensating valve and the outlet port communicate with each other through another variable throttle mechanism when the spool for mating is at the first position. The directional control valve device according to claim 9 or 10. 12. The directional control valve device according to claim 11, wherein each of the variable throttle mechanisms has a configuration in which the throttle is variable by a hydraulic pressure in the pressure receiving chamber, and a means for supplying pressure oil to the pressure receiving chamber is provided.