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

Abstract

A fluid valve, a fluid system, a construction machine, and a control method are provided. A fluid valve (14) of the present application includes a valve body having a spool bore (20) and a discharge port (D2) connected to the spool bore (20), and a spool (15) disposed in the spool bore (20) in a freely movable manner, wherein if the spool (15) is moved in one direction, the discharge port (D2) is connected to at least one of a regeneration flow path (37) and a tank flow path (136).

Description

TECHNICAL FIELD

[0001] The present application relates to a fluid valve, a fluid system, a construction machine, and a control method.

[0002] This application claims priority to Japanese Patent Application No. 2020-094289 filed on May 29, 2020, and Japanese Patent Application No. 2020-182784 filed on October 30, 2020, the contents of which are incorporated herein by reference. BACKGROUND

[0003] For example, a construction machine such as a hydraulic excavator is driven by a hydraulic system having a hydraulic actuator. For example, the hydraulic actuator is driven by working oil ejected from a pump (hydraulic pump). For example, the hydraulic system is provided with a fluid valve (hydraulic valve) that controls the flow rate of working oil ejected from the pump. For example, the hydraulic valve is provided with a valve body and a spool. The valve body has a spool hole and a flow path connected to the spool hole. The spool is disposed in the spool hole in a freely movable manner. For example, in Patent Literature 1, working oil from one pump flows from the hydraulic valve due to movement of the spool. The working oil from one pump flows from the hydraulic valve to the hydraulic actuator via the flow path.

[0004] Prior art documents

[0005] Patent documents

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2004-360751 SUMMARY

[0007] Problem to be solved by the invention

[0008] However, in the case of driving an actuator using a fluid, it is desirable to save energy.

[0009] The present application has been made in order to solve the above-described problems, with the aim of providing a fluid valve, a fluid system, a construction machine, and a control method that can save energy.

[0010] Solution to solve the problem

[0011] As a solution to the above-described problems, the present application has a configuration as follows.

[0012] (1) The fluid valve of the present application has a configuration as follows.

[0013] According to this structure, in a case where the discharge port is connected to the regeneration flow path due to movement of the spool in one direction, fluid from the discharge port can be used for regeneration of the actuator, and thus energy can be saved.

[0014] (2) In the fluid valve described in the above (1), the regeneration flow path can be a parallel flow path.

[0015] (3) In the fluid valve described in the above (1) or (2), the spool can have a notch capable of blocking the flow path and adjusting the flow rate.

[0016] (4) A fluid system according to an aspect of the present application includes: a pump that discharges fluid; and a fluid control device that has a fluid valve that controls the flow rate of fluid discharged from the pump and causes the fluid to flow to an actuator, the fluid valve having: a valve body that has a spool hole and a discharge port connected to the spool hole; and a spool that is disposed in the spool hole in a manner free to move, and if the spool is moved in one direction, the discharge port is connected to at least one of a regeneration flow path and a tank flow path.

[0017] According to this structure, in a case where the discharge port is connected to the regeneration flow path due to movement of the spool in one direction, fluid from the discharge port can be used for regeneration of the actuator, and thus energy can be saved.

[0018] (5) In the fluid system described in the above (4), the fluid system can further include a solenoid valve that moves the spool.

[0019] (6) In the fluid system described in the above (5), the fluid system can further include a control unit that controls the solenoid valve.

[0020] (7) A construction machine according to an aspect of the present application includes: a boom; a pump that discharges fluid; a fluid control device that has a fluid valve that controls the flow rate of fluid discharged from the pump; and an actuator to which fluid controlled in flow rate by the fluid valve flows, the actuator being used to drive the boom, the fluid valve having: a valve body that has a first spool hole, a second spool hole, and a discharge port connected to the second spool hole, an inlet adjusting spool that is disposed in the first spool hole in a manner free to move and controls the amount of supply of fluid with respect to the actuator; and an outlet adjusting spool that is disposed in the second spool hole in a manner free to move and controls the amount of discharge of fluid from the actuator, the fluid control device further including a solenoid valve that moves the outlet adjusting spool and a control unit that controls the solenoid valve, and if the outlet adjusting spool is moved in one direction, the discharge port is connected to a regeneration flow path.

[0021] According to the structure, the discharge port is connected to the regeneration flow path due to movement of the outlet regulation spool valve core in one direction, so that fluid from the discharge port is utilized (regenerated) for driving of the actuator, and thus energy saving can be achieved with a simple structure.

[0022] Further, the fluid valve has the inlet regulation spool valve core that controls the supply amount of fluid to the actuator, so that the supply amount of fluid to the actuator can be easily adjusted according to load variation of the actuator.

[0023] Further, the fluid valve has the outlet regulation spool valve core that controls the discharge amount of fluid from the actuator, so that the discharge amount of fluid from the actuator can be easily adjusted according to load variation of the actuator.

[0024] Further, the fluid control device has the electromagnetic valve that moves the outlet regulation spool valve core and the control section that controls the electromagnetic valve, so that driving control of the outlet regulation spool valve core can be electrically adjusted, and thus the circuit configuration can be simplified.

[0025] (8) The construction machine of the aspect of the present application has: a boom; a pump that ejects fluid; a fluid control device that has a fluid valve that controls the flow rate of fluid ejected from the pump; and an actuator to which fluid that has been flow rate-controlled by the fluid valve flows, the actuator being used to drive the boom, the fluid valve further having: a valve body that has a first spool valve core hole, a second spool valve core hole, and a discharge port that is connected to the second spool valve core hole; an inlet regulation spool valve core that is provided in the first spool valve core hole in a freely movable manner and controls the supply amount of fluid to the actuator; and an outlet regulation spool valve core that is provided in the second spool valve core hole in a freely movable manner and controls the discharge amount of fluid from the actuator, the fluid control device further having an electromagnetic valve that moves the outlet regulation spool valve core and a control section that controls the electromagnetic valve, and the discharge port is connected to the first spool valve core hole if the outlet regulation spool valve core is moved in one direction.

[0026] According to the structure, the discharge port is connected to the first spool valve core hole due to movement of the outlet regulation spool valve core in one direction, so that fluid from the discharge port is utilized (regenerated) for driving of the fluid valve, and thus energy saving can be achieved with a simple structure.

[0027] Further, the fluid valve has the inlet regulation spool valve core that controls the supply amount of fluid to the actuator, so that the supply amount of fluid to the actuator can be easily adjusted according to load variation of the actuator.

[0028] Further, the fluid valve has the outlet regulation spool valve core that controls the discharge amount of fluid from the actuator, so that the discharge amount of fluid from the actuator can be easily adjusted according to load variation of the actuator.

[0029] Further, the fluid control device has the electromagnetic valve that moves the outlet adjusting spool and the control section that controls the electromagnetic valve, so that the drive control of the outlet adjusting spool can be electrically adjusted, and thus the circuit configuration can be simplified.

[0030] (9) The construction machine according to the aspect of the present application includes: a boom; a pump that discharges fluid; a fluid control device that has a fluid valve that controls the flow rate of fluid discharged from the pump; and an actuator to which fluid that has been flow rate-controlled by the fluid valve flows, the actuator being used to drive the boom, the fluid valve having: a valve body that has a first spool hole, a second spool hole, and a discharge port that is connected to the second spool hole; an inlet adjusting spool that is provided in the first spool hole in a freely movable manner and controls the supply amount of fluid with respect to the actuator; and an outlet adjusting spool that is provided in the second spool hole in a freely movable manner and controls the discharge amount of fluid from the actuator; the fluid control device further has an electromagnetic valve that moves the outlet adjusting spool and a control section that controls the electromagnetic valve, and if the outlet adjusting spool is moved in one direction, the discharge port is connected to another actuator different from the actuator.

[0031] According to this structure, the discharge port is connected to another actuator due to the movement of the outlet adjusting spool in one direction, so that fluid from the discharge port can be utilized (regenerated) for the driving of another actuator, and thus energy saving can be achieved with a simple structure.

[0032] Further, the fluid valve has the inlet adjusting spool that controls the supply amount of fluid with respect to the actuator, so that the supply amount of fluid with respect to the actuator can be easily adjusted according to the load variation of the actuator.

[0033] Further, the fluid valve has the outlet adjusting spool that controls the discharge amount of fluid from the actuator, so that the discharge amount of fluid from the actuator can be easily adjusted according to the load variation of the actuator.

[0034] Further, the fluid control device has the electromagnetic valve that moves the outlet adjusting spool and the control section that controls the electromagnetic valve, so that the drive control of the outlet adjusting spool can be electrically adjusted, and thus the circuit configuration can be simplified.

[0035] (10) The control method according to the aspect of the present application includes: a raising process of raising a boom; and a lowering process of lowering the boom, in the raising process, a spool is moved in one direction to cause fluid from a discharge port of a fluid valve to flow back to a tank, and in the lowering process, the spool is moved in the other direction to regenerate the fluid from the discharge port.

[0036] According to the method, the fluid from the discharge port is regenerated in the lowering process, so that the fluid from the discharge port can be used (regenerated) for driving the actuator in the lowering operation of the boom, and thus energy saving is achieved.

[0037] Effects of the invention

[0038] According to the present application, a fluid valve, a fluid system, a construction machine, and a control method capable of saving energy can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0039] Fig. 1 is a schematic view of a construction machine of the first embodiment.

[0040] Fig. 2 is a schematic view of a hydraulic system of the first embodiment.

[0041] Fig. 3 is an explanatory view of one example of the operation of the hydraulic system when the inlet regulating spool valve core is in the neutral position of the first embodiment.

[0042] Fig. 4 is an explanatory view of one example of the operation of the hydraulic system when the boom is raised of the first embodiment.

[0043] Fig. 5 is an explanatory view of one example of the operation of the hydraulic system when the boom is lowered of the first embodiment.

[0044] Fig. 6 is an explanatory view of one example of the operation of the hydraulic system when the boom is lowered of the second embodiment.

[0045] Fig. 7 is an explanatory view of one example of the operation of the hydraulic system when the driving actuator is driven of the third embodiment.

[0046] Explanation of reference numerals

[0047] 1 hydraulic control device (fluid control device); 2 independent regulating valve (fluid valve); 3 valve body; 4 inlet regulating valve; 5 inlet regulating spool core; 10 1st spool core hole; 14 outlet regulating valve (fluid valve); 15 outlet regulating spool core; 15b shoulder; 15c notch; 16 1st outlet regulating solenoid proportional valve (solenoid valve); 17 2nd outlet regulating solenoid proportional valve (solenoid valve); 20 2nd spool core hole (spool core hole); 21 1st outlet regulating flow path (flow path); 22 2nd outlet regulating flow path (flow path); 25 control section; 37 bypass flow path (regeneration flow path); 100 hydraulic excavator (construction machine); 104 boom; 109, 209, 309 hydraulic system (fluid system); 113 hydraulic cylinder (actuator); 120, 320A, 320B, 320C tank; 120A 1st tank (tank); 120B 2nd tank (tank); 313A 1st cylinder (actuator); 313B 2nd cylinder (other actuator); 339 parallel flow path; A2 one direction movement of outlet regulating spool core; D1 1st discharge port (discharge port); D2 2nd discharge port (discharge port). DETAILED DESCRIPTION

[0048] Embodiments of the present application will be described below with reference to the accompanying drawings. In the following embodiments, as a construction machine, a hydraulic excavator provided with a hydraulic system (fluid system) is exemplified and described. Furthermore, in the drawings used in the following description, the reduction scale of each component is appropriately changed so as to set each component to an identifiable size.

[0049] <1st Embodiment>

[0050] <Construction Machine>

[0051] Fig. 1 is a schematic view of a construction machine 100 of the 1st embodiment.

[0052] As shown in Fig. 1 , the construction machine 100 is, for example, a hydraulic excavator. The construction machine 100 is provided with a swing body 101 and a traveling body 102. The swing body 101 is provided on the traveling body 102 in a swingable manner. On the swing body 101, a hydraulic pump 110 and a hydraulic control device (one example of a fluid control device) 1 that performs flow control of working oil (fluid) ejected from the hydraulic pump 110 are mounted.

[0053] The swing body 101 has a cab 103 in which an operator can get on, a boom 104 whose one end is linked to the swing body 101 in a swing-free manner, a stick 105 whose one end is linked to the other end (top end) of the boom 104 on the side opposite to the one end linked to the swing body 101 in a swing-free manner, a bucket 106 linked to the other end (top end) of the stick 105 on the side opposite to the one end linked to the boom 104 in a swing-free manner, and an operation section 107 provided to the cab 103. The traveling body 102, the swing body 101, the boom 104, the stick 105, and the bucket 106 are driven by various hydraulic actuators 111 (one example of the actuator in the claim). The hydraulic actuators 111 are driven by the working oil from the hydraulic pump 110 supplied via the hydraulic control device 1.

[0054] <Hydraulic system>

[0055] Fig. 2 is a schematic view of the hydraulic system 109 of the first embodiment. Fig. 2 is a schematic view of a cross section including the hydraulic control device 1.

[0056] As shown in Fig. 2 , the hydraulic system 109 has the hydraulic control device 1, the hydraulic pump 110, and the hydraulic actuators 111.

[0057] The hydraulic actuators 111 are constituted by, for example, a hydraulic motor 112 that makes the traveling body 102 travel and makes the swing body 101 swing, and various hydraulic cylinders (one example of the actuator in the claim) 113 for driving the boom 104, the stick 105, and the bucket 106 (see Fig. 1 ).

[0058] Hereinafter, one of the various hydraulic cylinders 113 will be described as a representative example. The representative example of the hydraulic cylinder 113 is a cylinder for driving one selected from the boom 104, the stick 105, and the bucket 106.

[0059] The hydraulic cylinder 113 has a cylinder 114, a piston rod 115 provided to the inside of the cylinder 114 in a slide-movement-free manner, a cap port (one example of the supply and discharge port of the actuator) Hp provided to the cylinder 114, and a rod port (one example of the supply and discharge port of the actuator) Rp. The hydraulic cylinder 113 has the cap port Hp and the rod port Rp as two supply and discharge ports.

[0060] The cap port Hp is provided to a portion 114a of the cylinder 114 located in the vicinity of the cylinder cap. The rod port Rp is provided to a portion 114b of the cylinder 114 located in the vicinity of the piston rod 115.

[0061] The hydraulic pump 110 is driven by a prime mover not shown. The hydraulic pump 110 makes the discharge amount of the working oil variable based on an operation signal of the operation section 107 provided to the cab 103 (see Fig. 1 ). In addition, the hydraulic control device 1 is driven controlled based on the operation signal of the operation section 107 (see Fig. 1 ).

[0062] In the embodiment, two hydraulic pumps 110 are provided. Hereinafter, one of the two hydraulic pumps 110 is referred to as "first pump 110A", and the other of the two hydraulic pumps 110 is referred to as "second pump 110B".

[0063] <Hydraulic Control Device>

[0064] The hydraulic control device 1 is provided with various IMVs (Independent Metering Valves) 2 (hereinafter also referred to as "independent adjustment valves"). The various independent adjustment valves 2 (one example of the fluid valve in the claim) control various hydraulic cylinders 113 for driving the swing boom 104, the arm 105, and the bucket 106.

[0065] Hereinafter, one of the various independent adjustment valves 2 is described as a representative example. The representative example of the independent adjustment valve 2 is a valve that controls a hydraulic cylinder 113 for driving one selected from the swing boom 104, the arm 105, and the bucket 106.

[0066] <Independent Adjustment Valve (IMV)>

[0067] The independent adjustment valve 2 is mainly composed of a valve body 3 (one example of the valve body in the claim), a round bar-shaped inlet adjustment spool 5 housed in the valve body 3, and a first inlet adjustment electromagnetic proportional valve (one example of the electromagnetic valve) 6 and a second inlet adjustment electromagnetic proportional valve (one example of the electromagnetic valve) 7 that move the inlet adjustment spool 5. The independent adjustment valve 2 adjusts the flow rate of the working oil discharged from the hydraulic pump 110 and makes the working oil flow to the hydraulic cylinder 113 using the movement of the inlet adjustment spool 5.

[0068] In addition, the independent adjustment valve 2 is mainly composed of a round bar-shaped outlet adjustment spool 15 (one example of the spool in the claim) housed in the valve body 3, and a first outlet adjustment electromagnetic proportional valve (one example of the electromagnetic valve in the claim) 16 and a second outlet adjustment electromagnetic proportional valve (one example of the electromagnetic valve in the claim) 17 that move the outlet adjustment spool 15.

[0069] Further, the independent adjustment valve 2 is provided with a control section 25 that controls the electromagnetic proportional valves 6, 7, 16, 17. The control section 25 is realized by a processor such as a CPU (Central Processing Unit) executing a program stored in a program memory. The control section 25 can be realized by hardware such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-Programmable Gate Array), or can be realized by cooperation of software and hardware.

[0070] The valve body 3 has a first spool hole 10 that houses the inlet adjustment spool 5, a first pump port P1 (one example of the parallel flow path in the claim), a second pump port P2 (one example of the parallel flow path in the claim), a first supply port S1, and a second supply port S2, which are connected to the first spool hole 10, a second spool hole 20 (one example of the spool hole in the claim) that houses the outlet adjustment spool 15, and a first tank port T1, a second tank port T2, a first discharge port D1 (one example of the discharge port in the claim), and a second discharge port D2 (one example of the discharge port in the claim), which are connected to the second spool hole 20.

[0071] Further, the valve body 3 and the inlet adjustment spool 5 are one example of the structure of the fluid system in the claim. Here, the flow path means a path for fluid to flow. The flow path includes not only a portion having a length in the direction of flow of fluid but also a flow inlet such as a pump port.

[0072] Further, the valve body 3 has a bridge flow path 30 that has an inverted U-letter shape in cross section, a first rod flow path 31 that is located on one side of the bridge flow path 30, a second rod flow path 32 that is connected to the first rod flow path 31, a first cover flow path 33 that is located on the other side of the bridge flow path 30, a second cover flow path 34 that is connected to the first cover flow path 33, a first tank flow path 35 that is located on the side of the first rod flow path 31, a second tank flow path 36 that is located on the side of the second rod flow path 32, and a bypass flow path 37 (one example of the regeneration flow path in the claim) that has a U-letter shape in cross section.

[0073] The first spool hole 10 and the second spool hole 20 are formed in the valve body 3 along a direction (i.e., an axial direction of the inlet regulating spool 5 and the outlet regulating spool 15). Cross sections of the first spool hole 10 and the second spool hole 20 along the axial direction are circular. The first spool hole 10 and the second spool hole 20 are formed in parallel, for example, in a manner spaced apart in a direction orthogonal to a length direction (i.e., an axial direction) of each spool hole 10, 20.

[0074] The first pump port P1 is connected to the first pump 110A by means of the first supply flow path 131. The first pump port P1 is a flow path that is able to supply the working oil from the first pump 110A to the plurality of hydraulic actuators 111.

[0075] The second pump port P2 is connected to the second pump 110B by means of the second supply flow path 132. The second pump port P2 is a flow path that is able to supply the working oil from the second pump 110B to the plurality of hydraulic actuators 111.

[0076] 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.

[0077] The first tank port T1 is connected to the tank 120 by means of the first discharge flow path 135. The second tank port T2 is connected to the tank 120 by means of the second discharge flow path 136. The first discharge port D1 is connected to the rod port Rp via each rod flow path 31, 32 and the rod side flow path 134. The second discharge port D2 is connected to the cap port Hp via each cap flow path 33, 34 and the cap side flow path 133.

[0078] Both ends of the bridge flow path 30 are connected to the first spool hole 10. The both ends of the bridge flow path 30 are disposed outside the first supply port S1 and the second supply port S2 in the axial direction.

[0079] The first rod flow path 31 is disposed between one end of the bridge flow path 30 and the first tank flow path 35 in the axial direction. The first rod flow path 31 extends in a direction orthogonal to the axial direction. The direction orthogonal to the axial direction corresponds to a paper up-down direction of FIG. 1. The first rod flow path 31 is connected to the first tank flow path 35 by means of the first relief valve 45 for releasing excessive high pressure. Fig. 2

[0080] The second rod flow path 32 is disposed between the first spool hole 10 and the second spool hole 20. The second rod flow path 32 is disposed on an extension line of the first rod flow path 31.

[0081] ​The first cap flow path 33 is disposed between the other end of the bridge flow path 30 and the second tank flow path 36 in the axial direction. The first cap flow path 33 extends in a direction orthogonal to the axial direction. The first cap flow path 33 is connected to the second tank flow path 36 by a second relief valve 46 for releasing excessive high pressure. A lock valve 47 for reducing leakage (a hold valve for suppressing lowering of the arm due to inertia) is provided in the first cap flow path 33.

[0082] The second cap flow path 34 is disposed between the first spool bore 10 and the second spool bore 20. The second cap flow path 34 extends in a direction orthogonal to the axial direction.

[0083] The first tank flow path 35 extends in a direction orthogonal to the axial direction outside the first rod flow path 31.

[0084] The second tank flow path 36 extends in a direction orthogonal to the axial direction outside the first cap flow path 33.

[0085] Both ends of the bypass flow path 37 are connected to the second spool bore 20. The bypass flow path 37 is connected to the first bypass port G1 and the second bypass port G2 via a third one-way valve 43 and a fourth one-way valve 44, respectively.

[0086] A first positioning mechanism 50 is provided at one end in the axial direction of the valve body 3. The first positioning mechanism 50 includes a first housing 51 attached to one end in the axial direction of the valve body 3 so as to block one end of each of the first spool bore 10 and the second spool bore 20. The first housing 51 has a first accommodation chamber 53 connected to one end of the first spool bore 10 and accommodating a first coil spring 52, and a second accommodation chamber 55 connected to one end of the second spool bore 20 and accommodating a second coil spring 54. In addition, the first housing 51 has a first pump flow path 56 extending in a direction orthogonal to the axial direction outside the first accommodation chamber 53 and the second accommodation chamber 55, and a first discharge flow path 57 extending in a direction orthogonal to the axial direction outside the first pump flow path 56.

[0087] A second positioning mechanism 60 is provided at the other end in the axial direction of the valve body 3. The second positioning mechanism 60 includes a second housing 61 attached to the other end in the axial direction of the valve body 3 so as to block the other end of each of the first spool bore 10 and the second spool bore 20. The second housing 61 has a third accommodation chamber 63 connected to the other end of the first spool bore 10, and a fourth accommodation chamber 65 connected to the other end of the second spool bore 20. In addition, the second housing 61 has a second pump flow path 66 extending in a direction orthogonal to the axial direction outside the third accommodation chamber 63 and the fourth accommodation chamber 65, and a second discharge flow path 67 extending in a direction orthogonal to the axial direction outside the second pump flow path 66.

[0088] The inlet regulating spool 5 is housed in the first spool hole 10 of the valve body 3 in a manner that is free to move in the axial direction. The inlet regulating spool 5 is housed in a manner that is positionable in three positions: a central position in the axial direction of the first spool hole 10 (see Fig. 3 ), a position on the one end side in the axial direction of the first spool hole 10 (see Fig. 4 ), and a position on the other end side in the axial direction of the first spool hole 10 (see Fig. 5 ).

[0089] Hereinafter, the central position in the axial direction of the first spool hole 10 will be referred to as the first central position. Also, the position on the one end side in the axial direction of the first spool hole 10 will be referred to as the first supply position, and the position on the other end side in the axial direction of the first spool hole 10 will be referred to as the second supply position.

[0090] The inlet regulating valve 4 is composed of the first spool hole 10, the inlet regulating spool 5, and the like. The inlet regulating valve 4 is a three-position four-way switching valve. The inlet regulating valve 4 performs flow control on the working oil that is ejected from the two pumps 110A, 110B.

[0091] The inlet regulating 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 notches 5c formed in the shoulders 5b. The inlet regulating spool 5 can block flow paths and adjust flow rates using the recesses 5a, the shoulders 5b, the notches 5c, and the like. Also, the inlet regulating spool 5 has, for example, a first inlet regulating flow path 11 formed by the recesses 5a, the notches 5c, and the like, and a second inlet regulating flow path 12 formed by the recesses 5a, the notches 5c, and the like (see Fig. 4 ).

[0092] Fig. 3 is a diagram that illustrates one example of the operation of the hydraulic system 109 when the inlet regulating spool 5 of the first embodiment is in the neutral position (the first neutral position).

[0093] As shown in Fig. 3 , in a state in which the inlet regulating spool 5 is disposed to the first neutral position, for example, the first pump port P1, the second pump port P2, the first supply port S1, and the second supply port S2 are blocked using the shoulders 5b and the like.

[0094] Fig. 4 is a diagram that illustrates one example of the operation of the hydraulic system 109 when the boom of the first embodiment is raised. Fig. 4 is a diagram that corresponds to the action of the piston rod 115 of the push-out hydraulic cylinder 113.

[0095] As shown in Fig. 4As shown, with the inlet regulating valve core 5 positioned in the first supply position, the first pump port P1 and the first supply port S1 are connected via the first inlet regulating flow path 11. The first inlet regulating flow path 11 is a flow path formed by recesses 5a, notches 5c, etc., and is a flow path along arrow Vs1. Furthermore, with the inlet regulating valve core 5 positioned in the first supply position, the second pump port P2 and the second supply port S2 are connected via the second inlet regulating flow path 12. The second inlet regulating flow path 12 is a flow path formed by recesses 5a, notches 5c, etc., and is a flow path along arrow Vs2. As a result, the first pump port P1 and the second pump port P2 are connected to the cover port Hp via the first supply port S1 and the second supply port S2, respectively. Furthermore, "connecting" (connecting) means allowing the working oil (i.e., fluid) to flow. For example, "using the first inlet regulating flow path 11 to connect the first pump port P1 with the first supply port S1" means that the first pump port P1 and the first supply port S1 are connected by the first inlet regulating flow path 11 to allow the working oil to flow.

[0096] Furthermore, with the inlet regulating slide valve core 5 configured in the first supply position, the rod port Rp is connected to the second rod flow path 32, etc.

[0097] Fig. 5 This is an explanatory diagram illustrating an example of the operation of the hydraulic system 109 when the boom is lowered according to the first embodiment. Fig. 5 This diagram illustrates the function of the piston rod 115, which is equivalent to pulling the hydraulic cylinder 113 in.

[0098] like Fig. 5 As shown, with the inlet regulating valve core 5 positioned in the second supply position, the first pump port P1 is connected to the first supply port S1 via the first inlet regulating flow path 11. Consequently, the first pump port P1 communicates with the rod port Rp via the first supply port S1. Furthermore, with the inlet regulating valve core 5 positioned in the second supply position, the second supply port S2 is blocked by the shoulder 5b, etc.

[0099] The inlet regulating valve core 5 is a valve core used to allow working oil injected from at least one of the two hydraulic pumps 110 to flow from the cover port Hp and the rod port Rp to the hydraulic cylinder 113 via the pump port, etc. In addition, the inlet regulating valve core 5 controls the amount of working oil supplied to the hydraulic cylinder 113 while allowing the working oil to flow to the hydraulic cylinder 113.

[0100] like Fig. 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.

[0101] The first inlet regulating solenoid proportional valve 6 and the second inlet regulating solenoid proportional valve 7 configure the inlet regulating spool 5 to the first neutral position (refer to FIG. 2) when neither of the inlet regulating solenoid proportional valves 6, 7 is energized. Fig. 3

[0102] In the de-energized state of the second inlet regulating solenoid proportional valve 7, the first inlet regulating solenoid proportional valve 6 is energized, thereby moving the inlet regulating spool 5 to configure the inlet regulating spool 5 to the first supply position (refer to FIG. 4). Here, the first inlet regulating solenoid proportional valve 6 can steplessly control (adjust) the first supply position in accordance with the "current value" (in proportion to which) of the energized electric signal. Fig. 4

[0103] In the de-energized state of the first inlet regulating solenoid proportional valve 6, the second inlet regulating solenoid proportional valve 7 is energized, thereby moving the inlet regulating spool 5 to configure the inlet regulating spool 5 to the second supply position (refer to FIG. 5). Here, the second inlet regulating solenoid proportional valve 7 can steplessly control (adjust) the second supply position in accordance with the "current value" (in proportion to which) of the energized electric signal. Fig. 5

[0104] The outlet regulating spool 15 is housed in the second spool hole 20 of the valve body 3 in a manner free to move in sliding motion in the axial direction. The outlet regulating spool 15 is housed in a manner positionable in three positions: a central position (refer to FIG. 6) in the axial direction of the second spool hole 20, a position on the one end side (refer to FIG. 7) in the axial direction of the second spool hole 20, and a position on the other end side (refer to FIG. 8) in the axial direction of the second spool hole 20. Fig. 3 Fig. 5 Fig. 4

[0105] Hereinafter, the central position in the axial direction of the second spool hole 20 will be referred to as the second central position. Also, the position on the one end side in the axial direction of the second spool hole 20 will be referred to as the first discharge position, and the position on the other end side in the axial direction of the second spool hole 20 will be referred to as the second discharge position.

[0106] The outlet regulating valve 14 is composed of the second spool hole 20 and the outlet regulating spool 15, and the like. The outlet regulating valve 14 is a three-position four-way switching valve, like the inlet regulating valve 4. The outlet regulating valve 14 is one example of the fluid valve in the claims.

[0107] ​​​​​​The outlet adjusting spool 15 has, for example, a plurality of recesses 15a formed in a ring shape, a plurality of shoulders 15b formed between the recesses 15a, and a plurality of notches 15c formed in the shoulders 15b. The outlet adjusting spool 15 can block the flow paths and adjust the flow rate using the recesses 15a, the shoulders 15b, the notches 15c, and the like. In addition, the outlet adjusting spool 15 has, for example, a first outlet adjusting flow path 21 (one example of the flow path in the claims, refer to Fig. 4 ) formed by the recesses 15a and the like, and a second outlet adjusting flow path 22 (one example of the flow path in the claims, refer to Fig. 5 ) formed by the recesses 15a and the like.

[0108] Fig. 3 is a diagram illustrating one example of the operation of the hydraulic system 109 when the outlet adjusting spool 15 of the first embodiment is positioned at the neutral position (second neutral position).

[0109] As shown in Fig. 3 , in a state where the outlet adjusting spool 15 is disposed to the second neutral position, for example, the first tank port T1, the second tank port T2, the first discharge port D1, the second discharge port D2, the first bypass port G1, and the second bypass port G2 are blocked by the shoulders 15b and the like.

[0110] As shown in Fig. 5 , in a state where the outlet adjusting spool 15 is disposed to the first discharge position, the second discharge port D2 is communicated with the second bypass port G2 by the second outlet adjusting flow path 22. In addition, in a state where the inlet adjusting spool 5 is disposed to the first discharge position, the cap port Hp is communicated with the second cap flow path 34 and the like. As a result, the cap port Hp is communicated with the bypass flow path 37 via the second discharge port D2 and the second bypass port G2.

[0111] In addition, in a state where the outlet adjusting spool 15 is disposed to the first discharge position, the first bypass port G1 is communicated with the second rod flow path 32 and the like. As a result, the second discharge port D2 is communicated with the second rod flow path 32 via the bypass flow path 37.

[0112] In addition, in a state disposed to the first discharge position, the second tank port T2 is blocked by the shoulders 15b and the like.

[0113] As shown in Fig. 4 , in a state where the outlet adjusting spool 15 is disposed to the second discharge position, the first tank port T1 and the first discharge port D1 are communicated by the first outlet adjusting flow path 21. As a result, the rod port Rp is communicated with the first tank port T1 via the first discharge port D1. In addition, in a state where the outlet adjusting spool 15 is disposed to the second discharge position, the second discharge port D2 is blocked by the shoulders 15b and the like.

[0114] The outlet regulating spool 15 is a spool for discharging the working oil in the hydraulic cylinder 113 from the cap port Hp, the rod port Rp, to the tank via the tank port, and the like. In addition, the outlet regulating spool 15 controls the discharge amount of the working oil from the hydraulic cylinder 113 at the time of discharging the working oil to the tank.

[0115] As shown in FIG. 1, the first inlet regulating electromagnetic proportional valve 6 and the second inlet regulating electromagnetic proportional valve 7 are provided on one end side of the inlet regulating spool 5. In addition, the first outlet regulating electromagnetic proportional valve 16 and the second outlet regulating electromagnetic proportional valve 17 are provided on the other end side of the inlet regulating spool 5. The first inlet regulating electromagnetic proportional valve 6 and the second inlet regulating electromagnetic proportional valve 7 are commonly used valves, and detailed explanation of the structure is omitted. Fig. 2

[0116] The first outlet regulating electromagnetic proportional valve 16 and the second outlet regulating electromagnetic proportional valve 17 configure the outlet regulating spool 15 to the second neutral position (refer to FIG. 2) when neither of the outlet regulating electromagnetic proportional valves 16, 17 is energized. Fig. 3

[0117] In the non-energized state of the second outlet regulating electromagnetic proportional valve 17, the first outlet regulating electromagnetic proportional valve 16 is energized, thereby moving the outlet regulating spool 15 to configure the outlet regulating spool 15 to the first discharge position (refer to FIG. 3). Here, the first outlet regulating electromagnetic proportional valve 16 can steplessly control (adjust) the first discharge position according to the "current value" (in proportion thereto) of the energized electric signal. Fig. 5

[0118] In the non-energized state of the first outlet regulating electromagnetic proportional valve 16, the second outlet regulating electromagnetic proportional valve 17 is energized, thereby moving the outlet regulating spool 15 to configure the outlet regulating spool 15 to the second discharge position (refer to FIG. 4). Here, the second outlet regulating electromagnetic proportional valve 17 can steplessly control (adjust) the second discharge position according to the "current value" (in proportion thereto) of the energized electric signal. Fig. 4

[0119] <Effect of independent regulating valve>

[0120] Next, the effect of the independent regulating valve 2 will be described.

[0121] As shown in FIG. 1, the first inlet regulating electromagnetic proportional valve 6 and the second inlet regulating electromagnetic proportional valve 7 are provided on one end side of the inlet regulating spool 5. In addition, the first outlet regulating electromagnetic proportional valve 16 and the second outlet regulating electromagnetic proportional valve 17 are provided on the other end side of the inlet regulating spool 5. The first inlet regulating electromagnetic proportional valve 6 and the second inlet regulating electromagnetic proportional valve 7 are commonly used valves, and detailed explanation of the structure is omitted. Fig. 3

[0122] ​​​​​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. 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.

[0123] 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 can also be returned to the tank via a return circuit (not shown).

[0124] like Fig. 4 As shown, the outlet regulating valve core 15 is moved in the direction of arrow A1 and positioned in the second discharge position. In this case, with the first outlet regulating solenoid proportional valve 16 de-energized, the second outlet regulating solenoid proportional valve 17 is switched to the energized state, thereby causing the outlet regulating valve core 15 to move towards the first outlet regulating solenoid proportional valve 16 (see reference). Fig. 2 The outlet regulating valve core 15 is positioned in the second discharge position by moving in the direction of the first outlet regulating flow path 21. This allows the first tank port T1 to communicate with the first discharge port D1. Consequently, the first tank port T1 communicates with the rod port Rp via the first outlet regulating flow path 21 and the first discharge port D1. Conversely, the second discharge port D2 is blocked by the outlet regulating valve core 15.

[0125] Additionally, the inlet regulating slide valve 5 is moved in the direction of arrow B1 and positioned in the first supply position. 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 the energized state, thereby causing the inlet regulating slide valve 5 to move towards the second inlet regulating solenoid proportional valve 7 (see reference). Fig. 2 The inlet regulating valve core 5 is positioned in the first supply position by moving in the direction of the first inlet regulating valve core 5. The first pump port P1 is connected to the first supply port S1 via the first inlet regulating flow path 11. Furthermore, the second pump port P2 is connected to the second supply port S2 via the second inlet regulating flow path 12 by 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, and 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.

[0126] Specifically, the first pump port P1 is made to communicate with the head port Hp via the first inlet regulating flow path 11, the first supply port S1, the first check valve 71, a portion of the bridge flow path 30, the first head flow path 33, and the head-side flow path 133, and the second pump port P2 is made to communicate with the head port Hp via the second inlet regulating flow path 12, the second supply port S2, the second check valve 72, a portion of the bridge flow path 30, the first head flow path 33, and the head-side flow path 133.

[0127] Further, by configuring the inlet regulating spool 5 in the first supply position, the rod port Rp is made to communicate with the second rod flow path 32 and the like.

[0128] In this state, the working oil in the cylinder 114 on the piston rod 115 side is discharged (returned) to the tank 120 as indicated by an arrow Vd1 via the rod port Rp, the first discharge port D1, the first outlet regulating flow path 21, and the first tank port T1. Specifically, the working oil in the cylinder 114 on the piston rod 115 side is discharged to the tank 120 as indicated by the arrow Vd1 via the rod port Rp, the rod-side flow path 134, the first rod flow path 31, the second rod flow path 32, the first discharge port D1, the first outlet regulating flow path 21, the first tank port T1, and the first discharge flow path 135. In the present embodiment, in the case where the boom is raised, the working oil from the first discharge port D1 is made to flow back to the tank 120.

[0129] On the other hand, the working oil ejected from the ejection port of the first pump 110A flows into the cylinder 114 on the cylinder head side as indicated by an arrow Vs1 via the first pump port P1, the first inlet regulating flow path 11, the first supply port S1, and the head port Hp. Specifically, the working oil ejected from the ejection port of the first pump 110A flows into the cylinder 114 on the cylinder head side as indicated by the arrow Vs1 via the first supply flow path 131, the first pump port P1, the first inlet regulating flow path 11, the first supply port S1, the first check valve 71, a portion of the bridge flow path 30, the first head flow path 33, the head-side flow path 133, and the head port Hp.

[0130] In addition, the working oil ejected from the ejection port of the second pump 110B flows into the cylinder 114 on the cylinder head side as indicated by an arrow Vs2 via the second pump port P2, the second inlet regulating flow path 12, the second supply port S2, and the head port Hp. Specifically, the working oil ejected from the ejection port of the second pump 110B flows into the cylinder 114 on the cylinder head side as indicated by the arrow Vs2 via the second supply flow path 132, the second pump port P2, the second inlet regulating flow path 12, the second supply port S2, the second check valve 72, a portion of the bridge flow path 30, the first head flow path 33, the head-side flow path 133, and the head port Hp.

[0131] In the hydraulic system 109 of this embodiment, when the inertial load is above a threshold, such as when the boom is raised, the working oil from the two pump ports P1 and P2 merges and flows from the inlet regulating valve 4.

[0132] That is, if the inlet regulating valve core 5 is moved in the direction of arrow B1 (one direction), the working oil from both pumps 110A and 110B flows together from the inlet regulating valve 4 through the two pump ports P1 and P2. The working oil sprayed from the two pumps 110A and 110B merges through the two pump ports P1 and P2, the two inlet regulating flow paths 11 and 12, and the first cover flow path 33, and flows from the inlet regulating valve 4 to the cylinder head side of the hydraulic cylinder 113.

[0133] Therefore, the piston rod 115 of the hydraulic cylinder 113 is pushed out in the direction of arrow E1 in a manner that protrudes from the cylinder 114.

[0134] like Fig. 5 As shown, the outlet regulating valve core 15 is moved in the direction of arrow A2 (an example of movement of the outlet regulating valve core in one direction as described in the claim) and positioned in the first discharge position. In this case, the second outlet regulating solenoid proportional valve 17 is switched to a de-energized state, and the first outlet regulating solenoid proportional valve 16 is switched to an energized state, thereby causing the outlet regulating valve core 15 to move towards the second outlet regulating solenoid proportional valve 17 (see...). Fig. 2 The outlet regulating valve core 15 is positioned in the first discharge position by moving in the direction of the outlet. By positioning the outlet regulating valve core 15 in the first discharge position, the second discharge port D2 is connected to the second bypass port G2 via the second outlet regulating flow path 22. As a result, the second bypass port G2 is connected to the cap port Hp via the second outlet regulating flow path 22 and the second discharge port D2. On the other hand, the outlet regulating valve core 15 blocks the first discharge port D1, the first can port T1, and the second can port T2.

[0135] Furthermore, by positioning the outlet regulating slide valve core 15 in the first discharge position, the first bypass port G1 is connected to the second rod flow path 32. Consequently, the second discharge port D2 is connected to the second rod flow path 32 via the bypass flow path 37.

[0136] Additionally, the inlet regulating slide valve 5 is moved in the direction of arrow B2 and positioned in the second supply position. In this case, the first inlet regulating solenoid proportional valve 6 is switched to the de-energized state, and the second inlet regulating solenoid proportional valve 7 is switched to the energized state, thereby causing the inlet regulating slide valve 5 to move towards the first inlet regulating solenoid proportional valve 6 (refer to...). Fig. 2) side is configured to the 2nd supply position. By configuring the inlet regulating spool 5 to the 2nd supply position, the 1st pump port P1 is communicated with the 1st supply port S1 by the 1st inlet regulating flow path 11. Thereby, the 1st pump port P1 is communicated with the rod port Rp via the 1st inlet regulating flow path 11 and the 1st supply port S1. On the other hand, the 2nd supply port S2 is blocked by the inlet regulating spool 5.

[0137] Specifically, the 1st pump port P1 is communicated with the rod port Rp via the 1st inlet regulating flow path 11, the 1st supply port S1, the 1st check valve 71, a part of the bridge flow path 30, the 1st rod flow path 31, and the rod side flow path 134.

[0138] In this state, the cylinder head side working oil in the cylinder 114 flows toward the 2nd rod flow path 32 (one example of a regeneration flow path) as an arrow Ve via the head port Hp, the 2nd discharge port D2, the 2nd outlet regulating flow path 22, and the 2nd bypass port G2, and the like. Specifically, the cylinder head side working oil in the cylinder 114 flows toward the rod port Rp as the arrow Ve via the head port Hp, the head side flow path 133, the 1st head flow path 33, the 2nd head flow path 34, the 2nd discharge port D2, the 2nd outlet regulating flow path 22, the 2nd bypass port G2, the bypass flow path 37, the 3rd check valve 73, the 1st bypass port G1, the 2nd rod flow path 32, the 1st rod flow path 31, and the rod side flow path 134. In the present embodiment, in the case where the boom is lowered, the working oil from the 2nd discharge port D2 is used for driving the hydraulic cylinder 113.

[0139] On the other hand, the working oil ejected from the ejection port of the 1st pump 110A flows into the piston rod 115 side in the cylinder 114 as an arrow Vs3 via the 1st pump port P1, the 1st inlet regulating flow path 11, the 1st supply port S1, and the rod port Rp. Specifically, the working oil ejected from the ejection port of the 1st pump 110A flows into the piston rod 115 side in the cylinder 114 as the arrow Vs3 via the 1st supply flow path 131, the 1st pump port P1, the 1st inlet regulating flow path 11, the 1st supply port S1, the 1st check valve 71, a part of the bridge flow path 30, the 1st rod flow path 31, the rod side flow path 134, and the rod port Rp. In the hydraulic system 109 of the present embodiment, when the inertial load is smaller than the threshold value in the case where the boom is lowered, only one of the working oils from the two pump ports P1, P2 (only the working oil from the 1st pump port P1) is made to flow from the inlet regulating valve 4.

[0140] That is, if the inlet regulating spool 5 is moved in the arrow B2 direction (the other direction), the working oil from only one of the two pumps 110A, 110B (only the first pump 110A) flows from the inlet regulating valve 4 via only one of the two pump ports P1, P2 (only the first pump port P1). The working oil ejected from the first pump 110A flows from the inlet regulating valve 4 via the first pump port P1, the first inlet regulating flow path 11, the first rod flow path 31, and the like toward the piston rod 115 side of the hydraulic cylinder 113. Further, if the outlet regulating spool 15 is moved in the arrow A2 direction, the working oil from the second discharge port D2 flows from the outlet regulating valve 14 toward the piston rod 115 side of the hydraulic cylinder 113.

[0141] Therefore, the piston rod 115 of the hydraulic cylinder 113 is pulled in the arrow E2 direction in a manner of being pushed into the cylinder 11.

[0142] As such, in the independent regulating valve 2, the inlet regulating spool 5 and the outlet regulating spool 15 are provided. The driving control of the inlet regulating spool 5 and the outlet regulating spool 15 can be used to move the piston rod 115 in both the arrow E1 and the arrow E2 directions. As such, the spool that switches the movement of the piston rod 115 in the two directions can be divided into the inlet regulating spool 5 and the outlet regulating spool 15.

[0143] Further, the inlet regulating spool 5 is driving controlled to the first supply position by the first inlet regulating electromagnetic proportional valve 6, and the outlet regulating spool 15 is driving controlled to the second discharge position by the second outlet regulating electromagnetic proportional valve 17. Therefore, the piston rod 115 of the hydraulic cylinder 113 can be moved in the arrow E1 direction (the one direction).

[0144] Moreover, the inlet regulating spool 5 is driving controlled to the second supply position by the second inlet regulating electromagnetic proportional valve 7, and the outlet regulating spool 15 is driving controlled to the first discharge position by the first outlet regulating electromagnetic proportional valve 16. Therefore, the piston rod 115 of the hydraulic cylinder 113 can be moved in the arrow E2 direction (the other direction).

[0145] Therefore, the driving control of the inlet regulating spool 5 and the driving control of the outlet regulating spool 15 can be independently electrically adjusted by the first inlet regulating electromagnetic proportional valve 6, the second inlet regulating electromagnetic proportional valve 7, the first outlet regulating electromagnetic proportional valve 16, and the second outlet regulating electromagnetic proportional valve 17. That is, the independent regulating valve 2 can be configured by the inlet regulating spool 5 and the outlet regulating spool 15. As a result, in the case where the actual machine adjustment of the independent regulating valve 2 (that is, the hydraulic control device 1) is performed in correspondence with the use such as a construction machine, the driving control of the inlet regulating spool 5 and the driving control of the outlet regulating spool 15 can be independently adjusted. Therefore, the actual machine adjustment can be easily performed, and the shortening of the adjustment period can be sought.

[0146] Specifically, 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.

[0147] Therefore, when adjusting the independent regulating valve 2 (hydraulic control device 1) according to its intended use in 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. This makes actual adjustments easier and shortens the adjustment period.

[0148] 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.

[0149] The hydraulic control device 1 in this embodiment 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 two 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 two 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.

[0150] Here, as Fig. 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.

[0151] As explained above, the construction machine 100 of the present embodiment is provided with: the boom 104; the pumps 110A, 110B that eject working oil; the hydraulic control device 1 that has the independent adjusting valve 2 that controls the flow rate of the working oil ejected from the pumps 110A, 110B; and the hydraulic cylinder 113 to which the working oil that is flow rate controlled by the independent adjusting valve 2 flows, the hydraulic cylinder 113 being used to drive the boom 104. The independent adjusting valve 2 is provided with: the valve body 3 that has the first spool hole 10, the second spool hole 20, and the discharge ports D1, D2 connected to the second spool hole 20; the inlet adjusting spool 5 that is provided in the first spool hole 10 in a freely movable manner, controls the supply amount of the working oil with respect to the hydraulic cylinder 113; and the outlet adjusting spool 15 that is provided in the second spool hole 20 in a freely movable manner, controls the discharge amount of the working oil from the hydraulic cylinder 113. The hydraulic control device 1 is provided with the solenoid valves 16, 17 that move the outlet adjusting spool 15, and the control section 25 that controls the solenoid valves 16, 17. If the outlet adjusting spool 15 is moved in the arrow A2 direction (one direction) by the independent adjusting valve 2, the second discharge port D2 is connected to the bypass flow path 37. The outlet adjusting spool 15 has the notch 15c and the shoulder 15b that can block the flow path and adjust the flow rate.

[0152] According to this structure, since the second discharge port D2 is connected to the bypass flow path 37 by the movement of the outlet adjusting spool 15 in the arrow A2 direction (one direction), the working oil from the second discharge port D2 can be used (regenerated) for the driving (regeneration) of the hydraulic cylinder 113, and thus, energy saving can be achieved with a simple structure.

[0153] Further, the independent adjusting valve 2 is provided with the inlet adjusting spool 5 that controls the supply amount of the working oil with respect to the hydraulic cylinder 113, and thus, the supply amount of the working oil with respect to the hydraulic cylinder 113 can be easily adjusted according to the load variation of the hydraulic cylinder 113.

[0154] Further, the independent adjusting valve 2 is provided with the outlet adjusting spool 15 that controls the discharge amount of the working oil from the hydraulic cylinder 113, and thus, the discharge amount of the working oil from the hydraulic cylinder 113 can be easily adjusted according to the load variation of the hydraulic cylinder 113.

[0155] Further, the hydraulic control device 1 is provided with the solenoid valves 16, 17 that move the outlet adjusting spool 15, and the control section 25 that controls the solenoid valves 16, 17, and thus, the driving control of the outlet adjusting spool 15 can be electrically adjusted, and thus, the circuit configuration can be simplified.

[0156] Further, the outlet adjusting spool 15 has the notch 15c and the shoulder 15b that can block the flow path and adjust the flow rate, and thus, the blocking of the flow path and the adjustment of the flow rate can be achieved with a simple structure.

[0157] The control method of the embodiment includes a raising process of raising the boom 104 and a lowering process of lowering the boom 104, in the raising process, the outlet regulating spool 15 is moved in the arrow Al direction (the other direction) to return the working oil from the first discharge port Dl to the tank 120, in the lowering process, the outlet regulating spool 15 is moved in the arrow A2 direction (the one direction) to regenerate the working oil from the second discharge port D2.

[0158] According to the method, in the lowering process, the working oil from the second discharge port D2 is regenerated, so that in the lowering operation of the boom 104, the working oil from the second discharge port D2 can be utilized (regenerated) for the driving of the hydraulic cylinder 113, and therefore, energy saving is possible.

[0159] In the above embodiment, an example in which two of the hydraulic pump 110 and the tank 120 are provided, respectively, is described, but the present application is not limited thereto. For example, one of the hydraulic pump 110 and the tank 120 can be provided, respectively, or three or more of the hydraulic pump 110 and the tank 120 can be provided, respectively. For example, the number of the hydraulic pump 110 and the tank 120 provided can be changed according to the required specifications.

[0160] In the above embodiment, an example in which the working oil from the second discharge port D2 is regenerated by flowing a part of the working oil to the bypass flow path 37 is described, but the present application is not limited thereto. For example, the working oil from the second discharge port D2 can be regenerated by flowing a part of the working oil to the bridge flow path 30. For example, the working oil from the second discharge port D2 can be regenerated by flowing a part of the working oil to the hydraulic pump 110. For example, the working oil from the second discharge port D2 can be regenerated by flowing a part of the working oil to the hydraulic cylinder 113 without passing through the bypass flow path 37 or the like. For example, the working oil from the second discharge port D2 can be regenerated by flowing all of the working oil to the bypass flow path 37. For example, all of the working oil from the second discharge port D2 can be flowed to the second discharge flow path 136. For example, it can be that, by moving the outlet regulating spool 15 further in the arrow A2 direction from the first discharge position shown, the second discharge port D2 and the second bypass port G2 are blocked by the outlet regulating spool 15, and the second discharge port D2 and the second tank port T2 are connected. That is, the discharge port connected to the second spool hole 20 can be connected to at least one of the regeneration flow path and the tank flow path. Fig. 5

[0161] In the above embodiment, an example in which the regeneration flow path 37 regenerates the working oil to the second rod flow path 32 is described, but the present application is not limited thereto. For example, the regeneration flow path 37 can be a flow path that regenerates the working oil to the cover flow paths 33, 34.

[0162] <2nd Embodiment>​

[0163] Fig. 6 This is an explanatory diagram illustrating an example of the operation of the hydraulic system 209 when the boom is lowered according to the second embodiment. Fig. 6 This diagram illustrates the function of the piston rod 115, which is equivalent to pulling the hydraulic cylinder 113 in.

[0164] In the first embodiment described above, an example was given where a portion of the working oil from the second discharge port D2 flows toward the rod port Rp when the boom is lowered, but this is not a limitation. For example, a portion of the working oil from the second discharge port D2 may also flow toward the first spool valve core orifice 10 (the flow path of the inlet regulating valve 4) when the boom is lowered. Fig. 6 In this document, structures identical to those in the first embodiment described above are labeled with the same reference numerals, and detailed descriptions thereof are omitted. Fig. 6 In the figure, reference numeral 238 indicates the intermediate flow path through the first slide valve core hole 10 and the second slide valve core hole 20.

[0165] like Fig. 6 As shown, in the hydraulic system 209 of this embodiment, when the boom is lowered, a portion of the working oil from the second discharge port D2 flows toward the first spool valve bore 10. Specifically, a portion of the working oil from the second discharge port D2 flows, as indicated by arrow Ve2, via the second outlet regulating flow path 22, the bypass flow path 37, the third check valve 73, and the intermediate flow path 238 toward the first pump port P1 connected to the first spool valve bore 10. The first pump port P1 becomes a parallel flow path capable of supplying working oil to another hydraulic actuator different from the boom. In this embodiment, when the boom is lowered, a portion of the working oil from the second discharge port D2 is guided to the first pump port P1 for (regeneration) to drive another hydraulic actuator. For example, the working oil flowing to the first pump port P1 can be used to drive the hydraulic pump 110, hydraulic cylinder 113, etc.

[0166] Alternatively, a portion of the working oil flowing into the intermediate flow path 238 may be configured to branch off from the intermediate flow path 238 and flow toward the first spool valve core hole 10, as shown by arrow Ve3. Or, all of the working oil flowing into the intermediate flow path 238 may be configured to branch off from the intermediate flow path 238 and flow toward the first spool valve core hole 10, as shown by arrow Ve3.

[0167] According to this structure, the second discharge port D2 is connected to the first valve core hole 10 due to the movement of the outlet regulating slide valve core 15 in the direction of arrow A2 (one direction), thereby enabling the working oil from the second discharge port D2 to be used (regenerated) for the drive of the inlet regulating valve 4. Therefore, energy saving is possible with a simple structure.

[0168] Further, for example, it can also be that all of the working oil from the second discharge port D2 flows to the second discharge flow path 136. For example, it can also be that by moving the outlet adjusting spool valve core 15 further in the direction of the arrow A2 from the position shown in the drawing, the second discharge port D2 and the second bypass port G2 are blocked by the outlet adjusting spool valve core 15, and the second discharge port D2 and the second tank port T2 are connected. That is, the discharge port connected to the second spool valve core hole 20 can be connected to at least one of the regeneration flow path and the tank flow path. Fig. 6

[0169] <Third Embodiment>

[0170] Fig. 7 is a drawing illustrating one example of the operation of the hydraulic system 309 in the case of the drive actuator of the third embodiment. Fig. 7 is a drawing illustrating the action equivalent to that of the piston rod 115 of the pull-in hydraulic cylinder 113.

[0171] In the above-described first embodiment, one example of the operation of the hydraulic system when the boom is raised and lowered was explained, but the present application is not limited thereto. For example, the present application can also be applied to the operation of the hydraulic system when the arm is pulled and pushed. In the above-described first embodiment, Fig. 7 In the above-described first embodiment, one example of the operation of the hydraulic system when the boom is raised and lowered was explained, but the present application is not limited thereto. For example, the present application can also be applied to the operation of the hydraulic system when the arm is pulled and pushed. In the above-described first embodiment,

[0172] As shown in Fig. 7 the hydraulic system 309 of the present embodiment is provided with one hydraulic pump 310, three tanks 320A to 320C, an inlet adjusting spool valve core 5 (inlet adjusting valve 4), an outlet adjusting spool valve core 15 (outlet adjusting valve 14), and two hydraulic cylinders 313A and 313B. Hereinafter, one of the two hydraulic cylinders 313A and 313B will be referred to as "first cylinder 313A", and the other will be referred to as "second cylinder 313B". The first cylinder 313A is one example of an actuator for driving a boom. The second cylinder 313B is one example of an actuator for driving an arm. The second cylinder 313B is one example of another actuator different from the actuator for driving the boom in the claims.

[0173] ​In the hydraulic system 309 of the present embodiment, in a case where the boom is lowered and the arm is pushed, working oil of the one hydraulic pump 310 is discharged, and flows toward the first cylinder 313A as an arrow Vcl due to movement of the inlet regulating spool 5 in the direction of the arrow Cll. A part of the working oil that flows from the first cylinder 313A toward the tank 320A flows toward the second cylinder 313B as an arrow Vc2 via the parallel flow path 339 and through the regeneration flow path (flow path along the arrow Vr), the discharge port (not shown) of the outlet regulating valve 14, due to movement of the outlet regulating spool 15 in the direction of the arrow C12 (one direction). The working oil discharged from the one pump 310 flows toward the piston rod 115 side of each of the first cylinder 313A and the second cylinder 313B. Therefore, the piston rod 115 of each of the first cylinder 313A and the second cylinder 313B is pulled in as the arrows Ea, Eb, respectively, in a manner of being pushed into the cylinder 114. In the present embodiment, in a case where the boom is lowered and the arm is pushed, a part of the working oil that flows from the first cylinder 313A toward the tank 320A is utilized (regenerated) for driving of the second cylinder 313B.

[0174] According to this structure, the discharge port of the outlet regulating valve 14 is connected to the second cylinder 313B due to movement of the outlet regulating spool 15 in the direction of the arrow C12 (one direction), so that working oil from the discharge port of the outlet regulating valve 14 can be utilized (regenerated) for driving of the second cylinder 313B, and thus energy saving can be achieved with a simple structure.

[0175] Further, the scope of the present application is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist of the present application.

[0176] For example, in the above-described embodiments, an example in which the construction machine 100 is a hydraulic excavator is described, but the present application is not limited thereto. For example, the present application can be applied to a construction machine other than a hydraulic excavator, such as a hydraulic crane.

[0177] In the above-described embodiments, an example in which the fluid system is a hydraulic system provided with a hydraulic control device is described, but the present application is not limited thereto. For example, the fluid system can be provided with a fluid control device other than a hydraulic control device, such as an air pressure control device or a water pressure control device.

[0178] In the above-described embodiments, an example in which the fluid system is provided with a pump, a fluid control device, and an actuator is described, but the present application is not limited thereto. For example, the fluid system can be provided with a fluid control device and an actuator without being provided with a pump. For example, the fluid system can be provided with a pump and a fluid control device without being provided with an actuator.

[0179] In the above-described embodiments, the hydraulic cylinder 113 is exemplified as the actuator, but the present application is not limited thereto. For example, the present application can be applied to an actuator such as a hydraulic motor.

[0180] In the above-described embodiments, the electromagnetic proportional valves 6, 7, 16, 17 are exemplified as the respective solenoid valves, but the present application is not limited thereto. For example, the present application can be applied to various solenoid valves driven based on electric signals.

[0181] Furthermore, the configuration elements in the above-described embodiments can be replaced with well-known configuration elements within a range not departing from the gist of the present application. In addition, the above-described various modifications can be combined.

Claims

1. A fluid system comprising: Pumps, which eject fluid; and A fluid control device having a fluid valve that controls the flow rate of fluid ejected from the pump and directs the fluid toward an actuator. In this fluid system, The fluid valve has: The valve body has a first spool valve core hole, a second spool valve core hole, and a discharge port connected to the second spool valve core hole; An inlet regulating slide valve core, which is freely movable and positioned within the first slide valve core orifice; and The outlet regulating slide valve core is positioned freely within the second slide valve core orifice. The fluid control device further includes a first solenoid valve for moving the inlet regulating slide valve core, a second solenoid valve for moving the outlet regulating slide valve core, and a control unit for controlling the first solenoid valve and the second solenoid valve. If the outlet regulating slide valve core is moved in one direction, the discharge port is connected to at least one of the regeneration flow path and the tank flow path. The discharge port is connected to a cover port or a rod port, which serves as the supply and discharge port of the actuator, to discharge fluid from the cover port or the rod port into the tank. The regeneration flow path is a flow path used to utilize fluid from the cover port or the rod port for the drive of the actuator.

2. A construction machine, comprising: boom; A pump, which ejects fluid; A fluid control device having a fluid valve for controlling the flow rate of fluid ejected from the pump; as well as An actuator, to which the flow rate of fluid controlled by the fluid valve flows, drives the boom. In this construction machinery, The fluid valve has: The valve body has a first spool valve core hole, a second spool valve core hole, and a discharge port connected to the second spool valve core hole. An inlet regulating slide valve core is disposed in the first slide valve core orifice in a freely movable manner to control the fluid supply relative to the actuator; as well as The outlet regulating slide valve core is freely movable within the second slide valve core orifice, controlling the discharge rate of fluid from the actuator. The fluid control device also includes a solenoid valve that moves the outlet regulating slide valve core and a control unit that controls the solenoid valve. If the outlet regulating valve core is moved in one direction, the discharge port is connected to the regeneration flow path. The discharge port is connected to a cover port or a rod port, which serves as the supply and discharge port of the actuator, to discharge fluid from the cover port or the rod port into the tank. The regeneration flow path is a flow path used to utilize fluid from the cover port or the rod port for the drive of the actuator.

3. A construction machine, comprising: boom; A pump, which ejects fluid; A fluid control device having a fluid valve for controlling the flow rate of fluid ejected from the pump; as well as An actuator, to which the flow rate of fluid controlled by the fluid valve flows, drives the boom. In this construction machinery, The fluid valve has: The valve body has a first spool valve core hole, a second spool valve core hole, and a discharge port connected to the second spool valve core hole; An inlet regulating slide valve core is disposed in the first slide valve core orifice in a freely movable manner to control the fluid supply relative to the actuator; as well as The outlet regulating slide valve core is freely movable within the second slide valve core orifice, controlling the discharge rate of fluid from the actuator. The fluid control device also includes a solenoid valve that moves the outlet regulating slide valve core and a control unit that controls the solenoid valve. If the outlet regulating slide valve core is moved in one direction, the discharge port is connected to the first slide valve core hole. The discharge port is connected to the cover port or rod port, which serves as the supply and discharge port of the actuator, to discharge fluid from the cover port or the rod port into the tank.

4. A construction machine, comprising: boom; A pump, which ejects fluid; A fluid control device having a fluid valve for controlling the flow rate of fluid ejected from the pump; as well as An actuator, to which the flow rate of fluid controlled by the fluid valve flows, drives the boom. In this construction machinery, The fluid valve has: The valve body has a first spool valve core hole, a second spool valve core hole, and a discharge port connected to the second spool valve core hole; An inlet regulating slide valve core is disposed in the first slide valve core orifice in a freely movable manner to control the fluid supply relative to the actuator; as well as The outlet regulating slide valve core is freely movable within the second slide valve core orifice, controlling the discharge rate of fluid from the actuator. The fluid control device also includes a solenoid valve that moves the outlet regulating slide valve core and a control unit that controls the solenoid valve. If the outlet regulating valve core is moved in one direction, the discharge port is connected to another actuator different from the aforementioned actuator. The discharge port is connected to the cover port or rod port, which serves as the supply and discharge port of the actuator, to discharge fluid from the cover port or the rod port into the tank.

5. A control method for construction machinery, the construction machinery comprising: a boom; a pump that ejects fluid; a fluid valve that controls the flow rate of the fluid ejected from the pump; and an actuator to which the fluid, whose flow rate is controlled by the fluid valve, flows, the actuator for driving the boom, the fluid valve comprising: a valve body having a first spool orifice, a second spool orifice, and a first discharge port and a second discharge port connected to the second spool orifice; an inlet regulating spool valve freely disposed in the first spool orifice to control the amount of fluid supplied relative to the actuator; and an outlet regulating spool valve freely disposed in the second spool orifice to control the amount of fluid discharged from the actuator. In this control method, The process includes the following steps: The lifting process that raises the boom; and The lowering process that lowers the boom The first discharge port is connected to the rod port, which serves as the supply and discharge port of the actuator, to discharge fluid from the rod port into the tank. The second discharge port is different from the first discharge port and is connected to the cover port, which serves as the supply and discharge port of the actuator. During the rising process, the outlet regulating valve core is moved in one direction to cause the fluid from the first discharge port to flow back into the tank. During the descent process, the outlet regulating valve core is moved in another direction to regenerate the fluid from the second discharge port.

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