Fluid valve, fluid system, construction machine, and control method

Abstract

The present application provides a kind of fluid valve, fluid system, construction machinery and control method. The independent regulating valve (2) of the present application is provided with valve body (3) and outlet regulating spool (15). Valve body (3) has: each discharge port (D1), (D2), which is connected with any one of each port (Rp), (Hp) arranged to hydraulic cylinder (113) driven by working oil;And each tank port (T1), (T2) is connected with each discharge flow path (135), (136). Outlet regulating spool (15) makes stem port (Rp) only communicate with cover port (Hp), or makes stem port (Rp) only communicate with the (2) tank port (T2), or makes stem port (Rp) communicate with cover port (Hp) and the (2) tank port (T2).

Description

Technical Field

[0001] This invention relates to a fluid valve, a fluid system, construction machinery, and a control method. Background Technology

[0002] For example, construction machinery such as hydraulic excavators is driven and controlled by a hydraulic system with hydraulic actuators. For instance, the hydraulic actuators are driven and controlled by working oil injected from a pump (hydraulic pump). In, for example, Patent Document 1, while working oil is supplied to the cylinder head side of the cylinder, the working oil on the cylinder rod side returns to the reservoir.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2004-360751 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] Thus, the construction machinery remains in a state where the working oil on the cylinder rod side returns to the tank from the time it reaches, for example, the digging position until the end of the digging. In this construction machinery, the desired outcome is the practical application of technologies that further improve the operability of the hydraulic actuator and enhance energy efficiency.

[0008] This invention provides a fluid valve, fluid system, construction machinery, and control method that improve the operability of actuators, achieve energy saving, and enable the use of actuators to perform operations such as excavation.

[0009] Solution for solving the problem

[0010] One aspect of the fluid valve of the present invention comprises: a valve body having: a supply / discharge port connected to one of a discharge port and a cylinder port disposed to a fluid-driven actuator; a tank port connected to a tank passage; and an outlet regulating slide valve core disposed freely within a sleeve hole formed in the valve body for controlling the discharge amount of the fluid from the actuator, wherein the outlet regulating slide valve core communicates only with the cylinder port and the discharge port, or only with the tank passage discharging the fluid and the discharge port, or with both the cylinder port and the tank passage connected to the discharge port.

[0011] With this configuration, due to the movement of the outlet regulating valve core, at least one of the cylinder port and the tank passage for discharging fluid is connected to the ejection port. For example, when fluid is supplied to the cylinder head side, the ejection port (i.e., the rod port) of the cylinder is connected to the cylinder port. Therefore, the fluid in the cylinder near the rod end can be regenerated by flowing towards the head end. By regenerating the fluid on the rod end side, the piston rod can be quickly ejected from the cylinder with less energy. This improves the operability of the actuator and achieves energy savings.

[0012] Furthermore, for example, when performing operations such as digging using an actuator, the ejection port (rod port) is connected to the tank passage, similar to a regular cylinder. Therefore, the piston rod can be protruded from the cylinder using only the fluid ejected from the pump. This allows for digging and other operations to be performed using the actuator.

[0013] Furthermore, by connecting to both the cylinder port and the canister passage, the flow rate of the fluid flowing from the rod end side to the cap end side in the cylinder can be adjusted. Thus, for example, the fluid flow rate can be adjusted with a simple structure according to the application of the actuator, and energy savings can be achieved.

[0014] In the above structure, the outlet regulating slide valve core can also be used to adjust the flow rate of the fluid flowing from the spray port only to the cylinder port, the flow rate flowing from the spray port only to the tank passage, and the flow rate flowing from the spray port to both the cylinder port and the tank passage by means of the movement of the outlet regulating slide valve core.

[0015] In the above structure, the outlet regulating slide valve core may also have a notch that blocks the flow path of the cylinder port and the tank passage, or adjusts the flow rate of the fluid flowing in the flow path.

[0016] In the above structure, the outlet regulating slide valve core may also have a shoulder that blocks the flow path of the cylinder port and the tank passage, or adjusts the flow rate of the fluid flowing in the flow path.

[0017] Another aspect of the fluid system of the present invention comprises: a fluid valve; an actuator driven by a fluid whose flow rate is adjusted by the fluid valve, the fluid valve comprising: a valve body having: a supply / discharge port connected to one of a discharge port and a cylinder port disposed to the fluid-driven actuator; a tank port connected to a tank passage; and an outlet regulating slide valve core disposed freely within a sleeve hole formed in the valve body to control the discharge amount of the fluid from the actuator, the outlet regulating slide valve core communicating only with the cylinder port and the discharge port, or only with the tank passage discharging the fluid and the discharge port, or with both the cylinder port and the tank passage communicating with the discharge port, the actuator comprising a cylinder and a piston rod disposed freely in the cylinder, the fluid system comprising a pressure sensor for detecting the pressure in the cylinder and / or the discharge pressure of a pump supplying the fluid to the cylinder port, and driving the outlet regulating slide valve core based on the detected pressure detected by the pressure sensor.

[0018] In this way, the outlet regulating spool can be driven based on the detected pressure from the pressure sensor, thus improving the operability of the actuator with a simple structure and achieving energy saving.

[0019] In the above structure, the ejection port can also be connected to the tank passage when the detection pressure is above the threshold, and connected to the cylinder port when the detection pressure is below the threshold.

[0020] In the above structure, the fluid system may also include a solenoid valve that drives the outlet regulating slide valve core based on an electrical signal.

[0021] In the above structure, the fluid system may also include a control unit that drives and controls the solenoid valve based on the detection signal from the pressure sensor.

[0022] Another aspect of the construction machinery of the present invention includes: a fluid valve; an actuator for driving a boom driven by a fluid whose flow rate is adjusted by the fluid valve, for driving the boom, the fluid valve including: a valve body having: a supply / discharge port connected to one of a discharge port and a cylinder port disposed to the fluid-driven actuator; a tank port connected to a tank passage; an outlet regulating slide valve core disposed freely within a sleeve hole formed in the valve body to control the discharge amount of the fluid from the actuator, the outlet regulating slide valve core communicating only with the cylinder port and the discharge port, or only with the tank passage discharging the fluid and the discharge port, or with both the cylinder port and the tank passage communicating with the discharge port, the actuator including a cylinder and a piston rod disposed freely within the cylinder, the construction machinery including a pressure sensor for detecting the pressure within the cylinder and / or the discharge pressure of a pump supplying the fluid to the cylinder port, and driving and controlling the outlet regulating slide valve core based on the detected pressure detected by the pressure sensor.

[0023] With this configuration, due to the movement of the outlet regulating valve core, at least one of the cylinder port and the tank passage for discharging fluid is connected to the ejection port. For example, when fluid is supplied to the cylinder head side, the ejection port (i.e., the rod port) of the cylinder is connected to the cylinder port. Therefore, the fluid in the cylinder near the rod end can be regenerated by flowing towards the head end. By regenerating the fluid on the rod end side, the piston rod can be quickly ejected from the cylinder with less energy. Thus, the operability of the construction machinery can be improved with a simple construction, and energy conservation in the construction machinery can be achieved.

[0024] Furthermore, for example, when performing operations such as digging using an actuator, similar to a conventional cylinder, the piston rod can be protruded from the cylinder using only the fluid ejected from the pump. Thus, operations such as digging can be performed using, for example, the boom of construction machinery.

[0025] Furthermore, by connecting to both the cylinder port and the tank passage, the flow rate of the fluid flowing from the rod end side to the cap end side in the cylinder can be adjusted. Thus, for example, the fluid flow rate can be adjusted with a simple structure according to the application of the construction machinery, and energy conservation can be achieved.

[0026] Another aspect of the construction machinery of the present invention comprises: a boom; an actuator that drives the boom by a fluid, having a cylinder and a piston rod disposed within the cylinder in a slidingly movable manner; an outlet regulating valve core connected to one of the ejection port and the cylinder port of the actuator, for controlling the discharge amount of the fluid from the actuator; a solenoid valve that drives the outlet regulating valve core based on an electrical signal; a pressure sensor that detects the pressure within the cylinder and / or the ejection pressure of the pump supplying the fluid to the cylinder port; and a control unit that detects the pressure by the pressure sensor. The detected pressure signal drives the solenoid valve, thereby driving the outlet regulating slide valve core. Due to the movement of the outlet regulating slide valve core, the concave and shoulder of the outlet regulating slide valve core block the flow path of the cylinder port and the tank passage through which the fluid is discharged, or adjust the flow rate of the fluid flowing in the flow path. Thus, when the detected pressure is above the threshold, the ejection port is connected to the tank passage; when the detected pressure is below the threshold, the ejection port is connected to the cylinder port, or the ejection port is connected to both the cylinder port and the tank passage.

[0027] With this configuration, when fluid is supplied to the cylinder head side, the cylinder's ejection port (i.e., the rod end) can be connected to the cylinder port. Therefore, the fluid in the cylinder near the rod end can flow towards the head end for regeneration. By utilizing the fluid on the rod end side, the piston rod can be quickly ejected from the cylinder with less energy. This improves the operability of the boom in construction machinery, and also achieves energy savings.

[0028] Furthermore, for example, when performing operations such as digging using an actuator, similar to a conventional cylinder, the piston rod can be protruded from the cylinder using only the fluid ejected from the pump. Thus, operations such as digging can be performed using, for example, the boom of construction machinery.

[0029] Furthermore, by connecting to both the cylinder port and the tank passage, the flow rate of the fluid flowing from the rod end side to the cap end side in the cylinder can be adjusted. Thus, the fluid flow rate can be adjusted with a simple structure according to the application, such as construction machinery, and energy conservation can be achieved.

[0030] Another aspect of the control method of the present invention includes the following steps: using a pressure sensor to detect the pressure inside the cylinder of the actuator and / or the ejection pressure of a pump supplying fluid to the cylinder port of the actuator; when the detected pressure of the pressure sensor is above a threshold, connecting the ejection port of the actuator to a tank passage for discharging the fluid; when the detected pressure of the pressure sensor is below the threshold, connecting the ejection port to the cylinder port, or connecting the ejection port to both the cylinder port and the tank passage.

[0031] By configuring the control method in such a way that when the pressure detected by the pressure sensor exceeds a threshold, the ejection port is connected to the tank passage, thus allowing the piston rod to protrude from the cylinder using only the fluid ejected from the pump, similar to a conventional cylinder. This enables operations such as digging to be performed using an actuator (i.e., the stick of construction machinery).

[0032] On the other hand, when the pressure detected by the pressure sensor is less than a threshold, the ejection port is connected to the cylinder port, thereby allowing the fluid in the cylinder near the rod end to flow towards the cap end for regeneration. By utilizing the fluid on the rod end side, the piston rod can be quickly ejected from the cylinder with less energy. This improves the operability of the actuator (i.e., the stick of the construction machinery) and achieves energy savings.

[0033] Furthermore, when the pressure detected by the pressure sensor is less than a threshold, the ejection port is connected to both the cylinder port and the canister passage, thereby allowing adjustment of the flow rate of the fluid flowing from the rod end side to the cap end side in the cylinder. Thus, for example, the fluid flow rate can be adjusted with a simple structure according to the application of the actuator, and energy savings can be achieved.

[0034] The effects of the invention

[0035] According to the present invention, the operability of the actuator is improved, energy saving is achieved, and the actuator can be used to perform operations such as digging. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the construction machinery according to an embodiment of the present invention.

[0037] Figure 2 This is a schematic diagram of a hydraulic system according to an embodiment of the present invention.

[0038] Figure 3 This is an explanatory diagram illustrating an example of the operation of the hydraulic system when pulling the boom according to an embodiment of the present invention.

[0039] Figure 4 This is an explanatory diagram illustrating an example of the operation of the hydraulic system when the bucket is pushed according to an embodiment of the present invention.

[0040] Explanation of reference numerals in the attached figures

[0041] 2. Independent regulating valve (fluid valve of claim); 3. Valve body; 10. First sleeve hole (sleeve hole); 15. Outlet regulating slide valve core; 15b. Shoulder; 15c. Notch; 16. First outlet regulating electromagnetic proportional valve (solenoid valve); 17. Second outlet regulating electromagnetic proportional valve (solenoid valve); 20. Second sleeve hole (sleeve hole); 25. Control unit; 26. Pressure sensor; 100. Construction machinery; 105. Stick; 10 6. Bucket; 109. Hydraulic system (fluid system); 113. Hydraulic cylinder (actuator); D1. First discharge port (supply and discharge port); D2. Second discharge port (supply and discharge port); Hp. Cover port (cylinder port); Rp. Rod port (ejection port); T1. First tank port (tank port); T2. Second tank port (tank port); 135. First discharge flow path (tank passage); 136. Second discharge flow path (tank passage). Detailed Implementation

[0042] Next, embodiments of the present invention will be described based on the accompanying drawings. In the following embodiments, a hydraulic excavator equipped with a hydraulic system (fluid system) will be used as an example of construction machinery for description. In the drawings used in the following description, the scale of each component has been appropriately changed in order to make each component recognizable.

[0043] <Construction Machinery>

[0044] Figure 1 This is a schematic diagram of the construction machinery 100 according to the implementation method.

[0045] like Figure 1 As shown, the construction machinery 100 is, for example, a hydraulic excavator. The construction machinery 100 includes a slewing body 101 and a traveling body 102. The slewing body 101 is mounted on the traveling body 102 in a rotatable manner. The slewing body 101 is equipped with a hydraulic pump 110 and a hydraulic control device (an example of a fluid control device) 1 for controlling the flow rate of the working oil (fluid) injected from the hydraulic pump 110.

[0046] The slewing body 101 includes: a cab 103 for the operator to sit in; a boom 104, one end of which is freely connected to the slewing body 101; a stick 105, one end of which is freely connected to the other end (top) of the boom 104 on the opposite side of the slewing body 101; a bucket 106, which is freely connected to the other end (top) of the stick 105 on the opposite side of the boom 104; and an operating unit 107 disposed in the cab 103. The traveling body 102, the slewing body 101, the boom 104, the stick 105, and the bucket 106 are driven by various hydraulic actuators 111. The hydraulic actuators 111 are driven by working oil supplied from a hydraulic pump 110 via a hydraulic control device 1.

[0047] <Hydraulic System>

[0048] Figure 2 This is a schematic diagram of the hydraulic system 109 of the embodiment. Figure 2 This is a schematic diagram of a cross-section including the hydraulic control device 1. Figure 2 In the figure, it indicates that the inlet regulating slide valve core 5 and the outlet regulating slide valve core 15 of the embodiment are in the neutral position (second neutral position) Po4.

[0049] like Figure 2 As shown, the hydraulic system (an example of the fluid system of the claim) 109 includes: a hydraulic control device 1; a hydraulic pump (an example of the pump of the claim) 110, which supplies working oil to the hydraulic control device 1; and a hydraulic actuator 111, which is driven and controlled by the hydraulic control device 1.

[0050] The hydraulic actuator 111 comprises, for example, the following components: a hydraulic motor 112, which drives the traveling body 102 and rotates the slewing body 101; and various hydraulic cylinders (an example of the actuator of the claim) 113, which drive the boom 104, the stick 105, and the bucket 106 (see reference). Figure 1 ).

[0051] The following description uses one hydraulic cylinder 113 from various hydraulic cylinders 113 as a representative example. The representative hydraulic cylinder 113 is a cylinder for driving the stick 105 selected by the driven boom 104, stick 105, and bucket 106.

[0052] The hydraulic cylinder 113 includes: a cylinder 114; a piston rod 115 disposed within the cylinder 114 in a slidingly movable manner; a cap port (an example of the cylinder port of the claim) Hp disposed in the cylinder 114; and a rod port (an example of the ejection port of the claim) Rp. The hydraulic cylinder 113 has the cap port Hp and the rod port Rp as two supply and discharge ports.

[0053] The cover port Hp is located at the cylinder head side of cylinder 114, at a position 114a. The rod port Rp is located at the piston rod side of cylinder 114, at a position 114b.

[0054] The hydraulic pump 110 is driven by a prime mover (not shown). The hydraulic pump 110 allows for variable injection volume of working oil based on an operation signal from the operating unit 107 located in the operator's cab 103 (see reference). Figure 1 Additionally, the hydraulic control device 1 is also driven and controlled based on the operation signal of the operation unit 107 (see reference). Figure 1 ).

[0055] There are two hydraulic pumps 110. Hereinafter, one of the two hydraulic pumps 110 will be referred to as "Pump 110A" and the other of the two hydraulic pumps 110 will be referred to as "Pump 210B".

[0056] <Hydraulic Control Device>

[0057] The hydraulic control unit 1 is equipped with various IMVs (Independent Metering Valves) 2 (hereinafter also referred to as "independent regulating valves"). The various independent regulating valves (an example of the fluid valves of the claims) 2 control various hydraulic cylinders 113 used to drive the boom 104, stick 105, and bucket 106.

[0058] The following description uses the independent control valve 2 of the boom 105 as a representative example among various independent control valves 2. The representative independent control valve 2 is a valve that controls the hydraulic cylinder 113 of the boom 105, which is used to drive the driven boom 104, the boom 105, and the bucket 106.

[0059] Independent Control Valve (IMV)

[0060] The independent regulating valve 2 is mainly composed of the following components: valve body 3; a cylindrical inlet regulating slide valve core 5, which is housed in the valve body 3; and a first inlet regulating electromagnetic proportional valve 6 and a second inlet regulating electromagnetic proportional valve 7, which drive and control the inlet regulating slide valve core 5.

[0061] In addition, the independent regulating valve 2 is mainly composed of the following components: a cylindrical outlet regulating slide valve core 15, which is housed in the valve body 3; and a first outlet regulating electromagnetic proportional valve (an example of the electromagnetic valve of the claim) 16 and a second outlet regulating electromagnetic proportional valve (an example of the electromagnetic valve of the claim) 17, which drive and control the outlet regulating slide valve core 15.

[0062] In addition, the independent regulating valve 2 has a control unit 25 that controls the electromagnetic proportional valves 6, 7, 16, and 17. The control unit 25 is implemented by a processor such as a CPU (Central Processing Unit) executing a program stored in the program memory. The control unit 25 can be implemented in hardware such as LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), or FPGA (Field-Programmable Gate Array), or it can be implemented through a combination of software and hardware.

[0063] Furthermore, the independent regulating valve 2 is equipped with a pressure sensor 26 that detects, for example, the internal pressure (an example of the cylinder pressure in the claim; cylinder pressure) on the cap-side of cylinder 114. The pressure sensor 26 is connected midway to the cap-side flow path 134, which will be discussed later. Based on the detected pressure by the pressure sensor 26, the control unit 25 controls the first outlet regulating solenoid proportional valve 16 and the second outlet regulating solenoid proportional valve 17. By controlling the first outlet regulating solenoid proportional valve 16 and the second outlet regulating solenoid proportional valve 17, the control outlet regulating spool valve 15 is driven.

[0064] In this embodiment, an example of detecting cylinder pressure using pressure sensor 26 is described, but it is not limited to this. As other examples, the injection pressure (pump pressure) of the first pump 110A and the second pump 110B can also be detected using, for example, a pressure sensor. Alternatively, the pressure sensor can be installed at the cap end of the cylinder 114, and the cylinder pressure at the cap end side can be detected directly using the pressure sensor.

[0065] The valve body 3 has: a first sleeve hole (an example of the sleeve hole of the claim) 10, which receives the inlet regulating slide valve core 5; a first pump port P1, a second pump port P2, a first supply port S1 and a second supply port S2, which are open in the first sleeve hole 10; a second sleeve hole (an example of the sleeve hole of the claim) 20, which receives the outlet regulating slide valve core 15; and a first tank port T1, a second tank port (an example of the tank port of the claim) T2, a first discharge port (an example of the supply and discharge port of the claim) D1 and a second discharge port (an example of the supply and discharge port of the claim) D2, which are open in the second sleeve hole 20.

[0066] Additionally, the valve body 3 includes: a bridge flow path 30; a first cover flow path 31 located on one side of the bridge flow path 30; a second cover flow path 32 connected to the first cover flow path 31; a first rod flow path 33 located on the other side of the bridge flow path 30; a second rod flow path 34 connected to the first rod flow path 33; a first tank flow path 35 located on the side of the first cover flow path 31; a second tank flow path 36 located on the side of the second rod flow path 34; and a bypass flow path 37, the cross-section of which is U-shaped along the axial direction.

[0067] The cross section of the bridge flow path 30 along one direction of the valve body 3 (i.e., the axial direction of the inlet regulating slide valve core 5 and the outlet regulating slide valve core 15, hereinafter, there may be cases where this axial direction is simply referred to as the axial direction) is formed in a U-shape.

[0068] The first sleeve hole 10 and the second sleeve hole 20 are formed along one direction of the valve body 3. The cross-section of the first sleeve hole 10 and the second sleeve hole 20 along the axial direction is circular. The first sleeve hole 10 and the second sleeve hole 20 are formed side by side, for example, in a direction orthogonal to the length direction (i.e., axial direction) of each sleeve hole 10, 20.

[0069] The first pump port P1 is connected to the first pump 110A via the first supply flow path 131. The second pump port P2 is connected to the second pump 110B via the second supply flow path 132. The first supply port S1 is connected to the bridge flow path 30 via the first check valve 41. The second supply port S2 is connected to the bridge flow path 30 via the second check valve 42.

[0070] The first can port T1 is connected to the can (an example of the can in the claim) 120 via a first discharge flow path (an example of the can passage in the claim) 135. The second can port T2 is connected to the can 120 via a second discharge flow path (an example of the can passage in the claim) 136. The first discharge port D1 is connected to the cap port Hp via each cap flow path 31, 32 and the cap-side flow path 134. The second discharge port D2 is connected to the rod port Rp via each rod flow path 33, 34 and the rod-side flow path 133.

[0071] Both ends of the bridge flow path 30 are connected to the first sleeve hole 10. The bridge flow path 30 is axially positioned outside the first supply port S1 and the second supply port S2.

[0072] The first cap flow path 31 is axially disposed between one end of the bridge flow path 30 and the first tank flow path 35. The first cap flow path 31 extends in a direction orthogonal to the axial direction. The first cap flow path 31 is connected to the first tank flow path 35 via a first relief valve 45 for releasing excessive high pressure.

[0073] The second cover flow path 32 is disposed between the first sleeve hole 10 and the second sleeve hole 20. The second cover flow path 32 is disposed on the extension line of the first cover flow path 31.

[0074] The first rod flow path 33 is axially positioned between the other end of the bridge flow path 30 and the second tank flow path 36. The first rod flow path 33 extends in a direction intersecting the axial direction. The first rod flow path 33 is connected to the second tank flow path 36 via a second relief valve 46 for releasing excessive high pressure. A locking valve 47 (a holding valve for preventing the boom 105 from descending due to inertia) is provided in the first rod flow path 33 to reduce leakage.

[0075] The second rod flow path 34 is disposed between the first sleeve hole 10 and the second sleeve hole 20. The second rod flow path 34 extends in a direction orthogonal to the axial direction.

[0076] The first can flow path 35 extends in a direction orthogonal to the axial direction on the side opposite to one end of the bridge flow path 30, with the first cover flow path 31 as a reference.

[0077] The second tank flow path 36 extends in a direction orthogonal to the axial direction on the side opposite to the other end of the bridge flow path 30, with the first rod flow path 33 as the reference.

[0078] The two ends of the bypass flow path 37 are connected to the second sleeve hole 20. The bypass flow path 37 is connected to the bypass port G1 via the third one-way valve 43.

[0079] A first positioning mechanism 50 is provided at one axial end of the valve body 3 (hereinafter, also simply referred to as one end, and the direction pointing to one end in the axial direction is also referred to as one end side). The first positioning mechanism 50 includes a first housing 51 installed to one axial end of the valve body 3 in such a way as to block one end of each of the first sleeve hole 10 and the second sleeve hole 20. The first housing 51 has: a first receiving chamber 53 connected to one end of the first sleeve hole 10, which receives a first helical spring 52; and a second receiving chamber 55 connected to one end of the second sleeve hole 20, which receives a second helical spring 54. In addition, the first housing 51 has: a first pump flow path 56 extending in a direction orthogonal to the axial direction at a position closer to one end than the first receiving chamber 53 and the second receiving chamber 55; and a first discharge flow path 57 provided at a position closer to one end than the first pump flow path 56, extending in a direction parallel to the first pump flow path 56. The first discharge path 57 extends in a direction orthogonal to the axial direction, just like the first pump path 56.

[0080] A second positioning mechanism 60 is provided at the other end of the valve body 3 in the axial direction (hereinafter, also simply referred to as the other end, and the direction pointing to the other end in the axial direction is also referred to as the other end side). The second positioning mechanism 60 includes a second housing 61 installed to the other end of the valve body 3 in the axial direction in a manner that blocks the other ends of the first sleeve hole 10 and the second sleeve hole 20 respectively. The second housing 61 has: a third receiving chamber 63 connected to the other end of the first sleeve hole 10; and a fourth receiving chamber 65 connected to the other end of the second sleeve hole 20. In addition, the second housing 61 has: a second pump flow path 66 extending in a direction orthogonal to the axial direction at a position closer to the other end side than the third receiving chamber 63 and the fourth receiving chamber 65; and a second discharge flow path 67 provided at a position closer to the other end side than the second pump flow path 66 and extending in a direction parallel to the second pump flow path 66. The second pump flow path 66 extends in the same direction orthogonal to the axial direction as the second pump flow path 66.

[0081] An inlet regulating slide valve core 5 is housed in the first sleeve hole 10 of the valve body 3 in a manner that allows it to slide freely in the axial direction. The inlet regulating slide valve core 5 is positioned at the axial center position Po1 of the first sleeve hole 10 and at one end position Po2 of the first sleeve hole 10 (see reference). Figure 3 ) and the position Po3 on the other axial end side of the first sleeve hole 10 (see Figure 4 ) are accommodated in such a manner as these three positions.

[0082] Hereinafter, the central position in the axial direction of the first sleeve hole 10 is referred to as the first central position Po1. In addition, the position on one axial end side of the first sleeve hole 10 is referred to as the first supply position Po2, and the position on the other axial end side of the first sleeve hole 10 is referred to as the second supply position Po3.

[0083] The inlet control valve 4 is composed of the first sleeve hole 10, the inlet control spool 5, etc. The inlet control valve 4 is a three-position four-way switching valve.

[0084] The inlet control spool 5 has, for example, a plurality of recesses 5a formed in a ring shape, a plurality of shoulders 5b formed between the recesses 5a, and a plurality of notch openings 5c formed in the shoulders 5b. The inlet control spool 5 can block the flow path and adjust the flow rate by using the recesses 5a, shoulders 5b, notch openings 5c, etc. In addition, the inlet control spool 5 has, for example: a first inlet control flow path 11 formed by the recesses 5a, notch openings 5c, etc.; and a second inlet control flow path 12 formed by the recesses 5a, notch openings 5c, etc.

[0085] In the state where the inlet control spool 5 is arranged at the first neutral position Po1, the first pump port P1, the second pump port P2, the first supply port S1, and the second supply port S2 are blocked by the shoulders 5b, etc.

[0086] Figure 3 It is an explanatory diagram of an example of the operation of the hydraulic system 109 when the stick 105 of the embodiment is used. Figure 3 It is an explanatory diagram of the function equivalent to the piston rod 115 of the extend cylinder 113.

[0087] As Figure 3 shown, in the state where the inlet control spool 5 is arranged at the first supply position Po2, the first pump port P1 is communicated with the first supply port S1 by the first inlet control flow path 11. In addition, in the state where the inlet control spool 5 is arranged at the first supply position Po2, the second pump port P2 is communicated with the second supply port S2 by the second inlet control flow path 12. As a result, the first pump port P1 and the second pump port P2 are respectively communicated with the cover port Hp via the first supply port S1 and the second supply port S2, etc. In addition, to communicate (communicate) means to make the working oil (i.e., fluid) flow. For example, "the first pump port P1 is communicated with the first supply port S1." means that the first pump port P1 is connected to the first supply port S1 to make the working oil flow.

[0088] Figure 4This is an explanatory diagram illustrating an example of the operation of the hydraulic system 109 when the pusher lever 105 is in the embodiment. Figure 4 This diagram illustrates the function of the piston rod 115, which is equivalent to pulling the hydraulic cylinder 113 in.

[0089] like Figure 4 As shown, with the inlet regulating valve core 5 positioned at the second supply position Po3, the first pump port P1 is connected to the first supply port S1 via the first inlet regulating flow path 11. Furthermore, with the inlet regulating valve core 5 positioned at the second supply position Po3, the second pump port P2 is connected to the second supply port S2 via the second inlet regulating flow path 12. As a result, the first pump port P1 and the second pump port P2 are connected to the rod port Rp via the first supply port S1 and the second supply port S2, respectively.

[0090] The inlet regulating valve core 5 is used to supply working oil injected from the two hydraulic pumps 110 to the hydraulic cylinder 113 via the pump port, etc., from the cover port Hp and the rod port Rp. In addition, the inlet regulating valve core 5 controls the amount of working oil supplied to the hydraulic cylinder 113 when supplying working oil to the hydraulic cylinder 113.

[0091] like Figure 2 As shown, a first inlet regulating electromagnetic proportional valve 6 is provided at one axial end of the inlet regulating slide valve core 5. A second inlet regulating electromagnetic proportional valve 7 is provided at the other axial end of the inlet regulating slide valve core 5. The first inlet regulating electromagnetic proportional valve 6 and the second inlet regulating electromagnetic proportional valve 7 are commonly used valves, and detailed descriptions of their structures are omitted.

[0092] When the first inlet regulating solenoid proportional valve 6 and the second inlet regulating solenoid proportional valve 7 are not energized, the inlet regulating slide valve core 5 is positioned in the first neutral position Po1.

[0093] With the second inlet regulating solenoid proportional valve 7 de-energized, the first inlet regulating solenoid proportional valve 6 is energized, thereby driving the inlet regulating slide valve 5 based on the electrical signal to position the inlet regulating slide valve 5 at the first supply position Po2 (refer to...). Figure 3 The first inlet regulating electromagnetic proportional valve 6 can steplessly control (adjust) the first supply position Po2 according to the "current value" (proportional to it) of the energized electrical signal.

[0094] With the first inlet regulating solenoid proportional valve 6 de-energized, the second inlet regulating solenoid proportional valve 7 is energized, thereby driving the inlet regulating slide valve 5 based on the electrical signal to position the inlet regulating slide valve 5 at the second supply position Po3 (refer to...). Figure 4The second inlet regulating electromagnetic proportional valve 7 can steplessly control (adjust) the second supply position Po3 according to the "current value" (proportional to it) of the energized electrical signal.

[0095] An outlet regulating slide valve core 15 is housed in the second sleeve hole 20 of the valve body 3 in a manner that allows it to slide freely in the axial direction. The outlet regulating slide valve core 15 is positioned at a central position Po4 in the axial direction of the second sleeve hole 20 and a position Po5 in front of one end of the second sleeve hole 20 in the axial direction. Figure 3 The middle position is Po4 to the right of the center position), and the position Po6 is located on one end of the axial direction of the second sleeve hole 20. Figure 3 The middle position is Po5 to the right of the center position), and the other end position Po7 on the axial side of the second sleeve hole 20 (refer to...). Figure 4 These four locations can be used for storage.

[0096] Hereinafter, the central position of the second sleeve hole 20 in the axial direction will be referred to as the second central position Po4. Furthermore, the position at one end of the second sleeve hole 20 in the axial direction will be referred to as the regeneration position Po5. Moreover, the position at one end of the second sleeve hole 20 in the axial direction will be referred to as the first discharge position Po6, and the position at the other end of the second sleeve hole 20 in the axial direction will be referred to as the second discharge position Po7.

[0097] The outlet regulating valve 14 is composed of the second sleeve hole 20 and the outlet regulating slide valve core 15, etc. The outlet regulating valve 14 is also a three-position four-way switching valve, just like the inlet regulating valve 4.

[0098] The outlet regulating valve core 15, for example, has a plurality of annular recesses 15a, a plurality of shoulders 15b formed between the recesses 15a, and a plurality of notches 15c formed on the shoulders 15b. The outlet regulating valve core 15 can block the flow path and adjust the flow rate using the recesses 15a, shoulders 15b, and notches 15c. Furthermore, the outlet regulating valve core 15, for example, has a first outlet regulating flow path 21 formed by the recesses 15a, etc. (see also...) Figure 4 ) and the second outlet regulating flow path 22 formed by the recess 15a, etc. (see also) Figure 3 ).

[0099] With the outlet regulating slide valve core 15 configured in the second neutral position Po4, the first tank port T1, the second tank port T2, the first discharge port D1, and the second discharge port D2 are blocked by means of, for example, shoulder 15b.

[0100] like Figure 3As shown, when the outlet regulating valve core 15 is positioned from the second central position Po4 to the regeneration position Po5, the second tank port T2 is connected to the second discharge port D2 via the second outlet regulating flow path 22. Furthermore, when the inlet regulating valve core 5 is positioned to the first discharge position Po2, the rod port Rp is connected to the second rod flow path 34 via the rod-side flow path 133 and the first rod flow path 33. As a result, the rod port Rp is connected to the bypass flow path 37 via the second discharge port D2.

[0101] Furthermore, with the outlet regulating slide valve core 15 configured in the regeneration position Po5, the bypass flow path 37 is connected to the second cover flow path 32 via the third check valve 43, etc. As a result, the bypass flow path 37 is connected to the cover port Hp via the second cover flow path 32, the first cover flow path 31, and the cover side flow path 134, etc.

[0102] Furthermore, with the outlet regulating valve core 15 further positioned from the regeneration position Po5 to the first discharge position Po6, the second tank port T2 is connected to the second discharge port D2 via the second outlet regulating flow path 22. Additionally, with the inlet regulating valve core 5 positioned at the first discharge position Po6, the rod port Rp is connected to the second rod flow path 34 via the rod-side flow path 133 and the first rod flow path 33. As a result, the rod port Rp is connected to the second tank port T2 via the second discharge port D2.

[0103] Thus, by moving the outlet regulating valve core 15 further from the regeneration position Po5 to the first discharge position Po6, the regeneration flow path is blocked, and working oil is discharged into the tank 120. Therefore, during regeneration with the outlet regulating valve core 15 positioned at the regeneration position Po5, the boom 105 can move at high speed; on the other hand, during digging, the outlet regulating valve core 15 can be moved to the first discharge position Po6 to dig with greater force.

[0104] like Figure 4 As shown, with the outlet regulating slide valve core 15 positioned at the second discharge position Po7, the first can port T1 is connected to the first discharge port D1 via the first outlet regulating flow path 21. As a result, the cap port Hp is connected to the first can port T1 via the first discharge port D1, the second cap flow path 32, the first cap flow path 31, and the cap side flow path 134.

[0105] The outlet regulating valve core 15 is a valve core used to discharge the working oil inside the hydraulic cylinder 113 from the cover port Hp, the rod port Rp, and the tank port to the tank. In addition, the outlet regulating valve core 15 controls the discharge amount of working oil from the hydraulic cylinder 113 when discharging working oil to the tank.

[0106] In addition, the outlet regulating spool 15 is a spool used to supply the working oil inside the hydraulic cylinder 113 from the cover port Hp and the rod port Rp to the inside of the hydraulic cylinder 113.

[0107] like Figure 2 As shown, a first outlet regulating solenoid proportional valve 16 is provided at one end of the outlet regulating slide valve core 15. Additionally, a second outlet regulating solenoid proportional valve 17 is provided at the other end of the outlet regulating slide valve core 15. The first outlet regulating solenoid proportional valve 16 and the second outlet regulating solenoid proportional valve 17 are commonly used valves, similar to the first inlet regulating solenoid proportional valve 6 and the second inlet regulating solenoid proportional valve 7; detailed structural descriptions are omitted.

[0108] When the first outlet regulating solenoid proportional valve 16 and the second outlet regulating solenoid proportional valve 17 are not energized, the outlet regulating slide valve core 15 is positioned in the second neutral position Po4.

[0109] With the second outlet regulating solenoid proportional valve 17 de-energized, the first outlet regulating solenoid proportional valve 16 is energized, thereby driving the outlet regulating slide valve 15 based on the electrical signal to position the outlet regulating slide valve 15 in the regeneration position Po5 (refer to...). Figure 3 The first outlet regulating electromagnetic proportional valve 16 can steplessly control (adjust) the regeneration position Po5 according to the "current value" (proportional to it) of the energized electrical signal.

[0110] With the second outlet regulating solenoid proportional valve 17 de-energized, the first outlet regulating solenoid proportional valve 16 is energized, thereby driving the outlet regulating slide valve 15 based on the electrical signal to position the outlet regulating slide valve 15 at the first discharge position Po6 (refer to...). Figure 3 The first outlet regulating electromagnetic proportional valve 16 can steplessly control (adjust) the first discharge position Po6 according to the "current value" (proportional to it) of the energized electrical signal.

[0111] With the first outlet regulating solenoid proportional valve 16 de-energized, the second outlet regulating solenoid proportional valve 17 is energized, thereby driving the outlet regulating slide valve 15 based on the electrical signal to position the outlet regulating slide valve 15 at the second discharge position Po7 (see reference). Figure 4 The second outlet regulating electromagnetic proportional valve 17 can steplessly control (adjust) the second discharge position Po7 according to the "current value" (proportional to it) of the energized electrical signal.

[0112] <Function of Independent Control Valve>

[0113] Next, the function of the independent regulating valve 2 will be explained.

[0114] like Figure 2As shown, the first inlet regulating solenoid proportional valve 6 and the second inlet regulating solenoid proportional valve 7 are set to the unenergized state, and the inlet regulating slide valve core 5 is positioned in the first neutral position Po1. The configured inlet regulating slide valve core 5 is used to block the first pump port P1, the second pump port P2, the first supply port S1, and the second supply port S2.

[0115] Additionally, the first outlet regulating solenoid proportional valve 16 and the second outlet regulating solenoid proportional valve 17 are set to the de-energized state, and the outlet regulating slide valve core 15 is positioned in the second neutral position Po4. The configured outlet regulating slide valve core 15 is used to block the first tank port T1, the second tank port T2, the first discharge port D1, and the second discharge port D2.

[0116] If each hydraulic pump 110A and 110B is driven by a prime mover (not shown), a predetermined flow rate of working oil is sprayed from the discharge port of each hydraulic pump 110A and 110B. For example, the sprayed working oil returns to the tank via a return circuit (not shown).

[0117] like Figure 3 As shown, the outlet regulating slide valve core 15 is moved from the second central position Po4 in the direction of arrow A1 and positioned in the regeneration position Po5. In this case, with the second outlet regulating solenoid proportional valve 17 de-energized, the first outlet regulating solenoid proportional valve 16 is switched to an energized state, thereby moving the outlet regulating slide valve core 15 toward the first outlet regulating solenoid proportional valve 16 and positioning it in the regeneration position Po5.

[0118] By positioning the outlet regulating slide valve core 15 in the regeneration position Po5, the second rod flow path 34 is connected to the bypass flow path 37 via the second discharge port D2.

[0119] Furthermore, with the outlet regulating slide valve core 15 configured in the regeneration position Po5, the bypass flow path 37 is connected to the second cover flow path 32, etc. As a result, the bypass flow path 37 is connected to the cover port Hp via the second cover flow path 32, etc.

[0120] Furthermore, the inlet regulating valve core 5 is moved in the direction of arrow B1 and positioned at the first supply position Po2. In this case, with the second inlet regulating solenoid proportional valve 7 de-energized, the first inlet regulating solenoid proportional valve 6 is switched to an energized state, thereby moving the inlet regulating valve core 5 towards the second inlet regulating solenoid proportional valve 7 and positioning it at the first supply position Po2. By positioning the inlet regulating valve core 5 at the first supply position Po2, the first pump port P1 is connected to the first supply port S1 via the first inlet regulating flow path 11. Additionally, by positioning the inlet regulating valve core 5 at the first supply position Po2, the second pump port P2 is connected to the second supply port S2 via the second inlet regulating flow path 12. As a result, the first pump port P1 is connected to the cover port Hp via the first inlet regulating flow path 11 and the first supply port S1. Furthermore, the second pump port P2 is connected to the cover port Hp via the second inlet regulating flow path 12 and the second supply port S2, etc.

[0121] Specifically, the first pump port P1 is connected via the first inlet regulating flow path 11, the first supply port S1, and the first check valve 41 (see reference). Figure 2 The bridge flow path 30, the first cover flow path 31, and the cover-side flow path 134 are connected to the cover port Hp. Additionally, the second pump port P2 is connected via the second inlet regulating flow path 12, the second supply port S2, and the second check valve 42 (see reference). Figure 2 The bridge flow path 30, the first cover flow path 31, and the cover side flow path 134 are connected to the cover port Hp.

[0122] On the other hand, by positioning the inlet regulating valve core 5 at the first supply position Po2, the rod port Rp is connected to the second rod flow path 34. As a result, the rod port Rp is connected to the bypass flow path 37 via the second discharge port D2. Thus, a regeneration passage is formed that connects the rod port Rp to the cover port Hp.

[0123] In this state, working oil sprayed from the first pump 110A is supplied to the first pump port P1, the first inlet regulating flow path 11, the first supply port S1, the first check valve 41, and a portion of the bridge flow path 30, as indicated by the arrow. Additionally, working oil sprayed from the second pump 110B is allowed to flow into the second pump port P2, the second inlet regulating flow path 12, the second supply port S2, the second check valve 42, and a portion of the bridge flow path 30, as indicated by the arrow.

[0124] The working oil sprayed from the first pump 110A and the working oil sprayed from the second pump 110B merge at a local point in the bridge flow path 30 and are supplied to the cover port Hp via the first cover flow path 31 and the cover side flow path 134, as indicated by the arrow.

[0125] Additionally, the working oil in cylinder 114 near piston rod 115 is guided, as indicated by the arrow, through rod port Rp, rod-side flow path 133, locking valve 47, first rod flow path 33, second rod flow path 34, and second discharge port D2 to bypass flow path 37. The working oil guided to bypass flow path 37 then flows towards third check valve 43 (see arrow). Figure 2 The working oil guided to the second cover flow path 32 flows into the cylinder head side of the cylinder 114 via the first cover flow path 31, the cover side flow path 134, and the cover port Hp, as indicated by the arrow.

[0126] That is, the working oil flowing out from the rod port Rp is regenerated by flowing into the cylinder head side of the cylinder 114 through the regeneration passage from the cover port Hp in full (i.e., 100%).

[0127] In this way, the inlet regulating valve core 5 moves to the first supply position Po2 and the outlet regulating valve core 15 moves to the regeneration position Po5, so that the working oil sprayed from the two pumps 110A and 110B merges and is supplied to the cylinder head side of the hydraulic cylinder 113.

[0128] On the other hand, the working oil in cylinder 114 on the piston rod 115 side flows from the rod port Rp through the cover port Hp into the cylinder head side of cylinder 114. As a result, the piston rod 115 of hydraulic cylinder 113 is pushed out in a manner that protrudes from cylinder 114 as shown by arrow E1.

[0129] Therefore, the boom 105 of the construction machinery 100 is pulled (or lowered) to the digging position. In this state, the cylinder pressure on the cylinder head side of the cylinder 114 rises above a threshold. The cylinder pressure is detected as a detection pressure by the pressure sensor 26. Therefore, when the detection pressure rises above the threshold, the control unit 25 switches the first outlet regulating solenoid proportional valve 16 to the energized state, thereby moving the outlet regulating slide valve core 15 in the direction of arrow A1 and positioning it at the first discharge position Po6. The function of positioning the outlet regulating slide valve core 15 at the first discharge position Po6 will be explained in detail below.

[0130] That is, when the cylinder pressure on the cylinder head side is less than a threshold, the regeneration passage connects the rod port Rp to the cover port Hp. Thus, the working oil flowing out from the rod port Rp is fully (i.e., 100%) guided to the cover port Hp via the regeneration passage and flows into the cylinder head side of the cylinder 114. Therefore, during regeneration when the outlet regulating valve core 15 is configured to the regeneration position Po5, the boom 105 can move at high speed.

[0131] Furthermore, in the implementation, but not limited to, the following example is described: the rod port Rp is connected only to the cap port Hp, and all (100%) of the working oil flowing out of the rod port Rp flows into the cylinder head side from the cap port Hp via the regeneration passage. As another example, the rod port Rp may be connected to both the cap port Hp and the tank 120. In this case, the working oil flowing out of the rod port Rp is divided into two streams flowing into the cap port Hp and the tank 120. That is, a portion of the working oil flowing out of the rod port Rp flows into the cylinder head side from the cap port Hp via the regeneration passage.

[0132] Next, by positioning the outlet regulating valve core 15 of the regeneration position Po5 at the first discharge position Po6, the second tank port T2 and the second discharge port D2 are connected via the second outlet regulating flow path 22. As a result, the second tank port T2 is connected to the rod port Rp via the second outlet regulating flow path 22 and the second discharge port D2. On the other hand, the first discharge port D1 is blocked by the outlet regulating valve core 15.

[0133] In this state, the working oil in cylinder 114 on the piston rod 115 side is discharged (returned) to tank 120 via rod port Rp, rod side flow path 133, locking valve 47, first rod flow path 33, second rod flow path 34, second discharge port D2, second outlet regulating flow path 22, and second tank port T2.

[0134] On the other hand, the working oil sprayed from the first pump 110A and the working oil sprayed from the second pump 110B continue to merge at a local point in the bridge flow path 30, and are supplied to the cover port Hp via the first cover flow path 31 and the cover side flow path 134 as indicated by the arrow. As a result, the piston rod 115 of the hydraulic cylinder 113 continues to be pushed out as indicated by the arrow E1, protruding from the cylinder 114.

[0135] In this state, construction machinery 100 (refer to) Figure 1 Continue pulling the boom 105 to begin digging. Thus, during digging by the construction machinery 100, the working oil flows back from the boom port Rp to the tank 120 as usual, thereby ensuring efficient digging force. That is, during digging, by moving the outlet regulating valve core 15 to the first discharge position Po6, digging with greater force is possible.

[0136] like Figure 4As shown, the outlet regulating valve core 15 is moved in the direction of arrow A2 and positioned at the second discharge position Po7. In this case, the first outlet regulating solenoid proportional valve 16 is switched to an unenergized state, and the second outlet regulating solenoid proportional valve 17 is switched to an energized state, thereby moving the outlet regulating valve core 15 towards the side of the first outlet regulating solenoid proportional valve 16 and positioning it at the second discharge position Po7. By positioning the outlet regulating valve core 15 at the second discharge position Po7, the first can port T1 is connected to the first discharge port D1 via the first outlet regulating flow path 21. As a result, the first can port T1 is connected to the cover port Hp via the first outlet regulating flow path 21, the first discharge port D1, the second cover flow path 32, the first cover flow path 31, and the cover-side flow path 134. On the other hand, the second can port T2 is blocked by the outlet regulating valve core 15.

[0137] Furthermore, the inlet regulating valve core 5 is moved in the direction of arrow B2 and positioned at the second supply position Po3. In this case, the first inlet regulating solenoid proportional valve 6 is switched to an unenergized state, and the second inlet regulating solenoid proportional valve 7 is switched to an energized state, thereby moving the inlet regulating valve core 5 towards the side of the first inlet regulating solenoid proportional valve 6 and positioning it at the second supply position Po3. By positioning the inlet regulating valve core 5 at the second supply position Po3, the first pump port P1 is connected to the first supply port S1 via the first inlet regulating flow path 11. As a result, the first pump port P1 is connected to the rod port Rp via the first inlet regulating flow path 11 and the first supply port S1, etc.

[0138] Furthermore, by positioning the inlet regulating slide valve core 5 at the second supply position Po3, the second pump port P2 is connected to the second supply port S2 via the second inlet regulating flow path 12. Thus, the second pump port P2 is connected to the rod port Rp via the second inlet regulating flow path 12 and the second supply port S2.

[0139] Specifically, the first pump port P1 is connected via the first inlet regulating flow path 11, the first supply port S1, and the first check valve 41 (see reference). Figure 2 The first rod flow path 33, the second rod flow path 30, and the rod-side flow path 133 are connected to the rod port Rp. Additionally, the second pump port P2 is connected via the second inlet regulating flow path 12, the second supply port S2, and the second check valve 42 (see reference). Figure 2 The bridge flow path 30, the first pole flow path 33, and the pole side flow path 133 are connected to the pole port Rp.

[0140] In this state, the working oil sprayed from the first pump 110A is supplied, as indicated by the arrow, to the first pump port P1, the first inlet regulating flow path 11, the first supply port S1, the first check valve 41, and a portion of the bridge flow path 30. Additionally, the working oil sprayed from the second pump 110B flows, as indicated by the arrow, into the second pump port P2, the second inlet regulating flow path 12, the second supply port S2, the second check valve 42, and a portion of the bridge flow path 30.

[0141] The working oil sprayed from the first pump 110A and the working oil sprayed from the second pump 110B merge at a local point in the bridge flow path 30 and are supplied to the rod port Rp via the first rod flow path 33 and the rod side flow path 133, as indicated by the arrow.

[0142] In addition, the working oil in cylinder 114 on the cylinder head side is discharged (returned) to tank 120 via the cover port Hp, cover side flow path 134, first cover flow path 31, second cover flow path 32, first discharge port D1, first outlet regulating flow path 21, and first tank port T1, as indicated by the arrow.

[0143] Therefore, the piston rod 115 of the hydraulic cylinder 113 is pulled in as indicated by arrow E1, in a manner that pushes it into the cylinder 114. As a result, the stick 105 of the construction machinery 100 is pushed away from the digging position (or raised upwards).

[0144] Thus, the independent regulating valve 2 has an inlet regulating slide valve core 5 and an outlet regulating slide valve core 15. The piston rod 115 can be moved in both directions, namely arrow E1 and arrow E2, by the drive control of the inlet regulating slide valve core 5 and the outlet regulating slide valve core 15. In this way, the slide valve core that switches the movement of the piston rod 115 in both directions can be divided into the inlet regulating slide valve core 5 and the outlet regulating slide valve core 15.

[0145] Furthermore, the inlet regulating spool 5 is driven and controlled to the first supply position Po2 using the first inlet regulating solenoid proportional valve 6. The outlet regulating spool 15 is driven and controlled to the regeneration position Po5 and the first discharge position Po6 using the second outlet regulating solenoid proportional valve 17. Therefore, the piston rod 115 of the hydraulic cylinder 113 can be moved in the direction of arrow E1 (one direction).

[0146] Furthermore, the inlet regulating spool 5 is driven and controlled to the second supply position Po3 by the second inlet regulating solenoid proportional valve 7. The outlet regulating spool 15 is driven and controlled to the second discharge position Po7 by the first outlet regulating solenoid proportional valve 16. Therefore, the piston rod 115 of the hydraulic cylinder 113 can be moved in the direction of arrow E2 (the other direction).

[0147] Therefore, the drive control of the inlet regulating valve core 5 and the drive control of the outlet regulating valve core 15 can be independently and electrically adjusted using the first inlet regulating solenoid proportional valve 6, the second inlet regulating solenoid proportional valve 7, the first outlet regulating solenoid proportional valve 16, and the second outlet regulating solenoid proportional valve 17. That is, the inlet regulating valve core 5 and the outlet regulating valve core 15 can constitute an independent regulating valve 2. As a result, when performing actual adjustments to the independent regulating valve 2 (i.e., the hydraulic control device 1) according to applications such as construction machinery, the drive control of the inlet regulating valve core 5 and the drive control of the outlet regulating valve core 15 can be adjusted independently. Therefore, actual adjustments to the hydraulic control device 1 can be easily performed, and the adjustment period can be shortened.

[0148] The first inlet regulating solenoid proportional valve 6 can steplessly adjust the first supply position proportionally to the "current value" of the energized electrical signal. The second inlet regulating solenoid proportional valve 7 can steplessly adjust the second supply position proportionally to the "current value" of the energized electrical signal. Furthermore, the first outlet regulating solenoid proportional valve 16 can steplessly adjust the first discharge position proportionally to the "current value" of the energized electrical signal. The second outlet regulating solenoid proportional valve 17 can steplessly adjust the second discharge position proportionally to the "current value" of the energized electrical signal.

[0149] Therefore, when adjusting the independent regulating valve 2 (hydraulic control device 1) according to its intended use, such as construction machinery, the drive control of the inlet regulating slide valve core 5 and the drive control of the outlet regulating slide valve core 15 can be adjusted steplessly. Consequently, the adjustment of the hydraulic control device 1 can be performed more easily, and the adjustment period can be shortened.

[0150] Furthermore, the inlet regulating solenoid proportional valve 6, the second inlet regulating solenoid proportional valve 7, the first outlet regulating solenoid proportional valve 16, and the second outlet regulating solenoid proportional valve 17 are used to drive and control the inlet regulating slide valve core 5 and the outlet regulating slide valve core 15. Therefore, the drive control of the inlet regulating slide valve core 5 and the outlet regulating slide valve core 15 can be electrically adjusted, which can meet the market expectations of future electrification and increase versatility.

[0151] The hydraulic control device 1 is configured to have one inlet regulating spool 5 and one outlet regulating spool 15, respectively, to switch the piston rod 115 of the hydraulic cylinder 113 in both directions. Therefore, the switching of the piston rod 115 in both directions can be shared between one inlet regulating spool 5 and one outlet regulating spool 15. Thus, it is unnecessary to have, for example, two separate inlet regulating spools and two separate outlet regulating spools for switching the piston rod 115 in both directions. Therefore, the circuit configuration of the independent regulating valves 2 (i.e., the inlet regulating spool and the outlet regulating spool) can be simplified.

[0152] like Figure 1 As shown, the construction machinery 100 is equipped with a hydraulic control device 1 with an independent regulating valve 2 on its rotating body 101. With this configuration, when the hydraulic control device 1 is adjusted in accordance with the purpose of the construction machinery 100, the drive control of the inlet regulating slide valve core 5 and the drive control of the outlet regulating slide valve core 15 can be adjusted independently, thereby shortening the adjustment time.

[0153] As explained above, according to the construction machinery 100 of this embodiment, when supplying working oil to the cylinder head side of cylinder 114, by positioning the outlet regulating valve core 15 in the regeneration position Po5, the rod port Rp and the cover port Hp of cylinder 114 can be connected via the regeneration passage. Therefore, the working oil in cylinder 114 near the rod end can flow towards the cover end for regeneration. Thus, by utilizing the working oil near the rod end for regeneration, the piston rod 115 can be rapidly (quickly) protruded from cylinder 114 as indicated by arrow E1 with less energy. Consequently, the operability of hydraulic cylinder 113 (i.e., boom 105) can be improved, and energy saving is achieved.

[0154] Alternatively, with the outlet regulating valve core 15 configured in the regeneration position Po5, the rod port Rp can be connected to both the cover port Hp and the tank 120. In this case, the working oil flowing out of the rod port Rp splits into two streams and flows into the cover port Hp and the tank 120 (i.e., the second discharge path 136). That is, a portion of the working oil flowing out of the rod port Rp can be regenerated by using the regeneration passage to flow from the cover port Hp into the cylinder head side.

[0155] Therefore, the piston rod 115 can be protruded from the cylinder 114 quickly, as shown by arrow E1, with less energy. This improves the operability of the hydraulic cylinder 113 (i.e., the boom 105) and achieves energy savings.

[0156] Furthermore, by connecting both the rod end Rp and the cap end Hp and the tank 120, the flow rate of the working oil flowing from the rod end side to the cap end side in the cylinder 114 can be adjusted. Therefore, for example, the flow rate of the working oil can be adjusted with a simple structure according to the application of the cylinder 114, and energy saving can be achieved.

[0157] Furthermore, when performing operations such as excavation using construction machinery 100, the outlet regulating valve core 15 is positioned in the first discharge position Po6. In this state, the rod port Rp is connected only to the tank 120. Therefore, the working oil in cylinder 114 on the piston rod 115 side returns to tank 120 from the rod port Rp via the second tank port T2. Thus, the piston rod 115 can be protruded from cylinder 114 as indicated by arrow E1 using only the working oil fluid ejected from the two pumps 110A and 110B. Therefore, excavation and other operations can be performed while efficiently ensuring the digging force generated by cylinder 114 (i.e., stick 105).

[0158] Furthermore, the independent regulating valve 2 is equipped with a pressure sensor 26, for example, a pressure sensor 26 that detects the cylinder pressure on the cap end side of the cylinder 114. Therefore, the control unit 25 can drive the control outlet regulating spool 15 based on the detected pressure detected by the pressure sensor 26.

[0159] That is, when the cylinder pressure is less than the threshold, the control unit 25 controls the outlet regulating slide valve core 15 to connect the rod port Rp and the cover port Hp. Therefore, the working oil flowing out from the rod port Rp can be fully (i.e., 100%) guided to the cover port Hp through the regeneration passage, so that it flows into the cylinder head side of the cylinder 114 for regeneration.

[0160] On the other hand, when the cylinder pressure rises above the threshold, the control unit 25 controls the outlet regulating slide valve core 15 to connect the rod port Rp to the tank port T2.

[0161] Thus, the outlet regulating spool valve 15 is driven by the pressure sensor to drive the control, thereby improving the operability of the hydraulic cylinder 113 with a simple structure and achieving energy saving.

[0162] Furthermore, the outlet regulating slide valve core 15 is configured to block the flow path and adjust the flow rate using, for example, a recess 15a, a shoulder 15b, and a notch 15c. Therefore, the recess 15a, shoulder 15b, and notch 15c can be used to form a simple structure that allows the working oil flowing from the rod port Rp to flow into the cover port Hp for regeneration.

[0163] Furthermore, a first outlet regulating solenoid proportional valve 16 and a second outlet regulating solenoid proportional valve 17 are incorporated into the drive section of the drive outlet regulating slide valve core 15. Therefore, a regeneration passage that allows the working oil flowing from the rod port Rp to flow into the cover port Hp can be formed with a simple structure.

[0164] Furthermore, based on the detection signal from the pressure sensor 26, the control unit 25 can drive and control the first inlet regulating solenoid proportional valve 6, the second inlet regulating solenoid proportional valve 7, the first outlet regulating solenoid proportional valve 16, and the second outlet regulating solenoid proportional valve 17. Therefore, a regeneration passage that allows the working oil flowing from the rod port Rp to flow into the cover port Hp can be formed with a simple structure.

[0165] Furthermore, the hydraulic system 109 is mounted on the construction machinery 100, and the cylinder 114 is used to drive the boom 105. Therefore, before performing operations such as digging using the boom 105, the working oil flowing out from the boom port Rp can flow into the cover port Hp for regeneration. As a result, the piston rod 115 can be quickly protruded from the cylinder 114 with less energy.

[0166] On the other hand, when performing digging or other operations using the boom 105, the piston rod 115 can be protruded from the cylinder 114 using only the working oil fluid sprayed from the two pumps 110A and 110B. Therefore, digging or other operations can be performed with high efficiency while ensuring the digging force generated by the cylinder 114 (i.e., the boom 105).

[0167] In this way, before using the boom 105 to perform digging or other operations, the working oil flowing from the boom port Rp is regenerated by flowing into the cover port Hp. As a result, the operability of the hydraulic cylinder 113 (i.e., the boom 105 of the construction machinery 100) can be improved, and energy saving can be achieved.

[0168] The control method of this embodiment includes the following steps: connecting the pressure sensor 26 to the tank 120 when the detected pressure is above a threshold; and connecting the pressure sensor 26 to the cover port Hp when the detected pressure is below a threshold.

[0169] During the connection process with tank 120, when the pressure detected by pressure sensor 26 is above the threshold, the rod port Rp is connected to tank 120. Therefore, similar to a normal cylinder, the piston rod 115 can be protruded from cylinder 114 using only the working oil sprayed from the two pumps 110A and 110B. Thus, digging and other operations can be performed using cylinder 114 (i.e., the stick 105 of the construction machinery 100).

[0170] On the other hand, during the process of connecting to the cover port Hp, when the pressure detected by the pressure sensor 26 is less than the threshold, by connecting the rod port Rp to the cover port Hp, the working oil on the rod end side of the cylinder 114 can flow into the cover end side for regeneration. Therefore, by utilizing the working oil on the rod end side, the piston rod 115 can be quickly protruded from the cylinder 114 with less energy. As a result, the operability of the hydraulic cylinder 113 (i.e., the boom 105 of the construction machinery 100) can be improved, and energy saving can be achieved.

[0171] In the aforementioned process of connecting to the cap port Hp, the rod port Rp can also be connected to both the cap port Hp and the tank 120. Therefore, the flow rate of the working oil flowing from the rod end side to the cap end side in the cylinder 114 can be adjusted. Consequently, for example, the flow rate of the working oil can be adjusted with a simple structure according to the application of the cylinder 114, and energy saving can be achieved.

[0172] Furthermore, the scope of protection of the present invention is not limited to the described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0173] For example, in the above embodiments, the construction machinery 100 was described as an example of a hydraulic excavator, but it is not limited thereto. For example, the present invention can also be applied to construction machinery other than hydraulic excavators, such as hydraulic cranes.

[0174] In the above embodiments, the fluid system has been described as an example of a hydraulic system equipped with a hydraulic control device, but it is not limited to this. For example, the fluid system may also be equipped with a fluid control device other than a hydraulic control device, such as an air pressure control device or a water pressure control device.

[0175] In the above embodiments, hydraulic cylinder 113 was described as an example of an actuator, but the invention is not limited thereto. The invention can also be applied to actuators such as hydraulic motors.

[0176] In the above embodiments, electromagnetic proportional valves 6, 7, 16, and 17 have been described as examples of solenoid valves, but the invention is not limited thereto. The invention can also be applied to various types of solenoid valves, for example, those driven by electrical signals. Alternatively, the electromagnetic proportional valves 6, 7, 16, and 17 can be replaced by using hydraulic pilot pressure to control the inlet regulating spool 5 and the outlet regulating spool 15.

[0177] Furthermore, without departing from the spirit of the present invention, the constituent elements of the above-described embodiments can be replaced with well-known constituent elements. Additionally, the various modifications described above can also be combined.

[0178] Industrial availability

[0179] According to the present invention, the operability of the actuator is improved, energy saving is achieved, and the actuator can be used to perform operations such as digging.

Claims

1. A fluid valve comprising: The valve body has: a supply port connected to one of a discharge port and a cylinder port disposed to a fluid-driven actuator; and a tank port connected to a tank passage. The outlet regulating slide valve core is freely movable within the sleeve hole formed in the valve body to control the discharge amount of the fluid from the actuator. The outlet regulating slide valve core, by moving, connects only the cylinder port to the ejection port, or connects both the cylinder port and the can passage to the ejection port.

2. The fluid valve according to claim 1, wherein, The outlet regulating slide valve core is used to adjust the flow rate of the fluid from the ejector port to the cylinder port only, or the flow rate of the fluid from the ejector port to both the cylinder port and the tank passage, by means of the movement of the outlet regulating slide valve core.

3. The fluid valve according to claim 1, wherein, The outlet regulating slide valve core has a notch that blocks the flow path of the cylinder port, the tank passage, or adjusts the flow rate of the fluid flowing in the flow path.

4. The fluid valve according to any one of claims 1 to 3, wherein, The outlet regulating slide valve core has a shoulder that blocks the flow path of the cylinder port, the tank passage, or adjusts the flow rate of the fluid flowing in the flow path.

5. A fluid system comprising: Fluid valve; An actuator, driven by fluid whose flow rate is adjusted by the fluid valve, The fluid valve includes: The valve body has: a supply port connected to one of a discharge port and a cylinder port disposed to the fluid-driven actuator; and a tank port connected to a tank passage. The outlet regulating slide valve core is freely movable within the sleeve hole formed in the valve body to control the discharge amount of the fluid from the actuator. The outlet regulating slide valve core, by its movement, can either connect the cylinder port to the injection port, or connect both the cylinder port and the tank passage to the injection port. The actuator includes a cylinder and a piston rod disposed within the cylinder in a slidingly movable manner. The fluid system includes a pressure sensor that detects the pressure inside the cylinder and / or the ejection pressure of the pump supplying the fluid to the cylinder port. The outlet regulating slide valve core is driven and controlled based on the detected pressure from the pressure sensor.

6. The fluid system according to claim 5, wherein, When the detected pressure is above the threshold, the ejection port is connected to the tank passage. When the detected pressure is less than the threshold, the injection port is connected to the cylinder port.

7. The fluid system according to claim 5, wherein, The fluid system is equipped with a solenoid valve that drives the outlet regulating slide valve core based on an electrical signal.

8. The fluid system according to claim 7, wherein, The fluid system includes a control unit that drives the solenoid valve based on the detection signal from the pressure sensor.

9. A construction machine, comprising: Fluid valve; An actuator for driving the stick, which is driven by a fluid whose flow rate is adjusted by the fluid valve, is used to drive the stick. The fluid valve includes: The valve body has: a supply port connected to one of a discharge port and a cylinder port disposed to the fluid-driven actuator; and a tank port connected to a tank passage. The outlet regulating slide valve core is freely movable within the sleeve hole formed in the valve body to control the discharge amount of the fluid from the actuator. The outlet regulating slide valve core, by its movement, can either connect the cylinder port to the injection port, or connect both the cylinder port and the tank passage to the injection port. The actuator includes a cylinder and a piston rod disposed within the cylinder in a slidingly movable manner. The construction machinery is equipped with a pressure sensor that detects the pressure inside the cylinder and / or the ejection pressure of the pump supplying the fluid to the cylinder port. The outlet regulating slide valve core is driven and controlled based on the detected pressure from the pressure sensor.

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