Flow adaptive load feedback multi-way valve

Abstract

The present application relates to hydraulic system, provide a kind of flow adaptive load feedback multi-way valve, including oil inlet association, multiple sequential arrangement work association, oil inlet oil circuit, pilot oil circuit, oil return oil circuit and load feedback oil circuit, oil inlet oil circuit is connected with each work association to be able to oil supply, oil return oil circuit is connected with each work association to be able to oil return, pilot oil circuit is connected each work association, to be able to corresponding control the valve opening of the main valve of work association, the output pressure of the main valve of each work association can be introduced into load feedback oil circuit, oil inlet association is provided with control valve, control valve can be according to the pressure difference between the oil pressure in oil inlet oil circuit and the oil pressure in load feedback oil circuit Control the communication state of pilot oil circuit and oil return oil circuit, to control the valve opening of the main valve core of each work association.The flow adaptive load feedback multi-way valve of the present application can link oil inlet oil circuit, load feedback oil circuit and pilot oil circuit, when composite action is carried out, can reasonably distribute oil flow, ensure the stable operation of actuator.

Description

Technical Field

[0001] This invention relates to hydraulic systems, and more specifically, to a flow-adaptive load feedback multi-way valve. Background Technology

[0002] Multi-way valves are widely used in construction machinery. For example, in the hydraulic system operating on the upper part of a truck crane, load feedback multi-way valves are used to control the actions of multiple actuators. The coordination of the combined actions of multiple actuators affects the overall work efficiency and the personal safety of the driver.

[0003] The load feedback multi-way valve is divided into an inlet oil circuit, a load feedback oil circuit, and a pilot oil circuit. The three oil circuits are separate and independent and do not affect each other. The input oil in the inlet oil circuit and the pilot oil circuit that controls the valve stem through load feedback have no effect. The movement of the valve stem (the opening and closing size of the valve port) is entirely determined by the amount of pilot oil. The larger the control oil, the larger the valve port opening, and vice versa, thus realizing the function of changing the size of the flow output of the valve port.

[0004] However, since there is no linkage between the oil inlet circuit, the load feedback circuit, and the pilot circuit, when the multi-way valve performs a combined action, if one of the pressure compensators has insufficient flow when the two or more actuators are running at maximum pressure, the pressure compensator will open completely, causing the pressure of that actuator to suddenly disappear, resulting in unstable actuator action with shocks, and disrupting the coordination of the combined action of multiple actuators. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a flow adaptive load feedback multi-way valve that can link the oil inlet circuit, the load feedback circuit and the pilot circuit to achieve reasonable distribution of oil flow and stable operation of the actuator when performing compound actions.

[0006] To address the aforementioned technical problems, this invention provides a flow-adaptive load feedback multi-way valve, comprising an inlet line, multiple sequentially arranged working lines, an inlet oil circuit, a pilot oil circuit, a return oil circuit, and a load feedback oil circuit. The inlet oil circuit connects the inlet line to each of the working lines to supply oil. The return oil circuit connects the inlet line to each of the working lines to return oil. The pilot oil circuit connects each of the working lines to control the valve opening of the main valve core of each working line. The output pressure of the main valve core of each working line can be introduced into the load feedback oil circuit. The system is equipped with control valves, which are respectively connected to the inlet oil circuit, the pilot oil circuit, the return oil circuit, and the load feedback oil circuit. The valve core of the control valve can control the connection state between the pilot oil circuit and the return oil circuit. The hydraulic oil in the inlet oil circuit and the hydraulic oil in the load feedback oil circuit act on the opposite ends of the valve core of the proportional control valve, so as to control the connection state between the pilot oil circuit and the return oil circuit according to the pressure difference between the oil pressure in the inlet oil circuit and the oil pressure in the load feedback oil circuit, thereby controlling the valve opening of the main valve core of each working unit.

[0007] Specifically, the proportional control valve is a proportional control valve, the valve body of which includes a proportional control valve core and a proportional control valve chamber. The proportional control valve chamber includes an inlet chamber connected to the inlet oil circuit, a control chamber connected to the pilot oil circuit, a return oil chamber connected to the return oil circuit, and a load feedback chamber connected to the load feedback oil circuit. The proportional control valve core is movably disposed within the proportional control valve chamber. The inlet oil chamber and the load feedback chamber are respectively disposed at opposite ends of the proportional control valve core, so that the proportional control valve core can move according to the pressure difference between the oil pressure in the inlet oil chamber and the oil pressure in the load feedback chamber, thereby controlling the communication state between the control chamber and the return oil chamber. A control spring is disposed within the load feedback chamber, which can drive the proportional control valve core to move closer to the inlet oil chamber.

[0008] Specifically, the proportional control valve core includes a control sealing part, a channel part, and a valve core positioning part arranged in sequence. The control sealing part is located between the oil inlet chamber and the control chamber to form a seal between the oil inlet chamber and the control chamber. The channel part forms an oil passage connecting the return oil chamber with the inner wall of the proportional control valve chamber. One end of the control sealing part connected to the channel part is a valve core opening section. The valve core opening section moves into the control chamber so that the oil passage connects with the control chamber. The valve core positioning part is located between the return oil chamber and the load feedback chamber to form a seal between the return oil chamber and the load feedback chamber.

[0009] Preferably, the valve core positioning part near the load feedback cavity forms a spring mounting groove for installing the control spring. The valve body of the control valve includes a threaded sleeve, which is installed corresponding to the load feedback cavity so that the inner cavity of the threaded sleeve communicates with the load feedback cavity. A spring seat is provided in the inner cavity of the threaded sleeve. The two ends of the control spring abut against the bottom of the spring mounting groove and the side of the spring seat near the load feedback cavity, respectively. A pressure adjusting screw is connected to the side of the spring seat away from the load feedback cavity. The end of the pressure adjusting screw away from the spring seat extends out from the threaded hole of the threaded sleeve. By screwing the pressure adjusting screw in or out, the spring seat can be moved closer to or away from the control spring. A locking nut is connected to the end of the pressure adjusting screw extending from the threaded sleeve.

[0010] Preferably, the valve body is provided with an oil inlet, a control oil inlet, a return oil inlet, and a load feedback oil inlet connected to the outside. The oil inlet is connected to the oil inlet chamber, the control oil inlet is connected to the control chamber, the return oil inlet is connected to the return oil chamber, and the load feedback oil inlet is connected to the load feedback chamber. The oil inlet, the control oil inlet, and the load feedback oil inlet are respectively provided with a first damping plug, a second damping plug, and a third damping plug.

[0011] Specifically, each of the working links includes a secondary hoisting link, a main hoisting link, a luffing link, and a telescopic link arranged in sequence. The main valve of each working link is connected to a pressure compensation valve to control the hydraulic oil pressure difference between the input and output of the main valve core of each working link to be constant. Each working link has a pilot proportional valve at both ends of the main valve to control the position state of the main valve core. The pilot proportional valve is connected to the pilot oil circuit.

[0012] Preferably, the auxiliary hoisting unit includes an auxiliary hoisting pressure compensation valve and a first shuttle valve; the main hoisting unit includes a main hoisting pressure compensation valve and a second shuttle valve; the luffing unit includes a luffing pressure compensation valve and a third shuttle valve; and the telescopic unit includes a telescopic pressure compensation valve. The output ports of the telescopic pressure compensation valve and the luffing pressure compensation valve are respectively connected to the first comparison port and the second comparison port of the third shuttle valve. The output ports of the third shuttle valve and the main hoisting pressure compensation valve are respectively connected to the first comparison port and the second comparison port of the second shuttle valve. The output ports of the second shuttle valve and the auxiliary hoisting pressure compensation valve are respectively connected to the first comparison port and the second comparison port of the first shuttle valve. The output port of the first shuttle valve is connected to the load feedback oil circuit.

[0013] Preferably, the spring control chambers of the auxiliary lifting pressure compensation valve, the main lifting pressure compensation valve, the luffing pressure compensation valve, and the telescopic pressure compensation valve are all connected to the load feedback oil circuit, and each of the working pressure compensation valves is provided with a throttling orifice on the oil circuit connecting it to the load feedback oil circuit.

[0014] Preferably, the oil inlet union includes a pilot reducing valve, and the oil inlet oil path is connected to the pilot oil path through the pilot reducing valve.

[0015] More preferably, the oil inlet union includes a pilot relief valve. The pilot relief valve is respectively connected to the pilot oil path and the oil return path, and the output port of the pilot relief valve is connected to the spring control chamber of the pilot reducing valve.

[0016] Through the above solution, the beneficial effects of the present invention are as follows:

[0017] The self - adaptive load - feedback multi - way valve of the present invention connects the control valve to the oil inlet oil path, the pilot oil path, the oil return path and the load - feedback oil path respectively. The control valve can control the movement of its spool according to the difference between the inlet oil pressure of the oil inlet oil path and the load pressure of the load - feedback oil path, so that the pilot oil path is connected to the oil return path, and adjusts the valve port opening according to the size of the difference, so that a part of the pressure of the pilot oil path is relieved, and then changes the control pressure of the main spools of each working union, adjusts the valve port opening of the main spools of each working union, so as to be able to adjust the output flow of the main valves of each working union, realize the linkage of the oil inlet oil path, the pilot oil path and the load - feedback oil path, and ensure that when the self - adaptive load - feedback multi - way valve of the present invention performs a compound action, it can reasonably distribute the flow rate and ensure the stable operation of the actuator.

[0018] Other features and advantages of the present invention will be described in detail in the subsequent specific implementation part. Brief Description of the Drawings

[0019] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and are used to explain the present invention together with the following specific implementation manners, but do not constitute a limitation to the present invention. In the drawings:

[0020] Figure 1 is the hydraulic schematic diagram of a specific embodiment of the self - adaptive load - feedback multi - way valve of the present invention;

[0021] Figure 2 is Figure 1 the partial enlarged view at position A in

[0022] Figure 3 is the structural schematic diagram of a specific embodiment of the proportional control valve;

[0023] Figure 4 is the structural schematic diagram of the spool of a specific embodiment of the proportional control valve in the left extreme position;

[0024] Figure 5 is the structural schematic diagram of the spool of a specific embodiment of the proportional control valve in the right extreme position;

[0025] Figure 6 This is a structural schematic diagram of another specific implementation of a proportional control valve core.

[0026] Explanation of reference numerals in the attached figures

[0027] 1. Oil inlet control valve 11

[0028] 111 proportional control valve core 1111 control seal

[0029] 1112 Channel section 1113 Valve core positioning section

[0030] 1114 Valve core opening section; 1115 Spring mounting groove

[0031] 1116 Cross Groove 1117 Center Oil Hole

[0032] 112 proportional control valve chamber 1121 oil inlet chamber

[0033] 1122 Control chamber 1123 Oil return chamber

[0034] 1124 Load feedback chamber; 113 Control spring

[0035] 114 threaded sleeve, 115 spring seat

[0036] 116 Pressure regulating screw 117 Locking nut

[0037] 118 First damper 119 Second damper

[0038] 1110 Third damping plug 12 Pilot pressure reducing valve

[0039] 13 Pilot-operated relief valve

[0040] 2 sets of lifting couplings and 21 sets of lifting pressure compensation valves

[0041] 22 First shuttle valve; 23 Secondary hoisting main valve core

[0042] 24 First hoisting pilot proportional valve 25 Second hoisting pilot proportional valve

[0043] 3 Main lifting linkage 31 Main lifting pressure compensation valve

[0044] 32 Second shuttle valve

[0045] 4-Amplitude Joint 41 Amplitude Pressure Compensation Valve

[0046] 42 Third shuttle valve

[0047] 5. Telescopic Joint 51 Telescopic Pressure Compensating Valve

[0048] 100 oil inlet circuit 200 pilot oil circuit

[0049] 300 return oil circuit 400 load feedback oil circuit

[0050] p oil inlet t oil return port

[0051] pk control oil port ls load feedback oil port Detailed Implementation

[0052] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the present invention, and the scope of protection of the present invention is not limited to the specific embodiments described below.

[0053] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "forming," "having," "setting," and "connecting," etc., should be interpreted broadly. For example, a connection can be a direct connection or an indirect connection through an intermediate medium; it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate connector; it can be the internal communication of two elements or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0054] In this invention, unless otherwise specified, the directional terms "up," "down," "left," and "right" used to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention. The directional terms of this invention should be understood in conjunction with the actual installation state.

[0055] This invention provides a flow adaptive feedback multi-way valve, see [link to relevant documentation]. Figure 1 and Figure 2As a specific embodiment of the flow adaptive feedback multi-way valve of the present invention, it includes an oil inlet link 1, multiple sequentially arranged working links, an oil inlet passage 100, a pilot oil passage 200, a return oil passage 300, and a load feedback oil passage 400. The oil inlet passage 100 connects the oil inlet link 1 to each working link to supply oil. The return oil passage 300 connects the oil inlet link 1 to each working link to return oil. The pilot oil passage 200 connects each working link to control the valve opening of the main valve core of each working link. The output pressure of the main valve core of each working link can be introduced into the load feedback oil passage 400. The oil inlet link 1 is equipped with a control valve. 11. Control valve 11 is connected to oil inlet circuit 100, pilot oil circuit 200, return oil circuit 300 and load feedback oil circuit 400 respectively. The valve core of control valve 11 can control the connection state between pilot oil circuit 200 and return oil circuit 300. The hydraulic oil in oil inlet circuit 100 and hydraulic oil in load feedback oil circuit 400 act on the opposite ends of the valve core of control valve 11 respectively, so as to control the connection state between pilot oil circuit 200 and return oil circuit 300 according to the pressure difference between the oil pressure in oil inlet circuit 100 and the oil pressure in load feedback oil circuit 400, thereby controlling the valve opening of the main valve core of each working link.

[0056] The flow adaptive load feedback multi-way valve of this invention establishes a linkage relationship between the inlet oil passage 100, the pilot oil passage 200, and the load feedback oil passage 400 through the control valve 11. During compound operation, two or more actuators are in operation. When the pressure difference between the oil pressure in the inlet oil passage 100 and the oil pressure in the load feedback oil passage 400 is less than a set value, the valve core of the control valve 11 is driven to move under the action of the oil pressure, so that the valve core of the control valve 11 is in the working position that connects the pilot oil passage 200 and the return oil passage 300. This allows part of the pressure in the pilot oil passage 200 to be discharged from the return oil passage 300, thereby reducing the control pressure of the pilot oil passage 200 on the main valve core of the corresponding working link of the actuator. This causes the valve opening of the main valve core of the working link to decrease synchronously, so as to reasonably distribute the flow, establish the pressure difference before and after the valve core of the main valve of the working link, and ensure the stable operation of the actuator.

[0057] In order to ensure that the valve opening of control valve 11 changes proportionally to the pressure difference between the oil pressure in the inlet oil passage 100 and the oil pressure in the load feedback oil passage 400, control valve 11 is preferably a proportional control valve. (See [reference needed]) Figure 3The proportional control valve body includes a proportional control valve core 111 and a proportional control valve chamber 112. The proportional control valve chamber 112 includes an inlet chamber 1121 connected to the inlet oil passage 100, a control chamber 1122 connected to the pilot oil passage 200, a return oil chamber 1123 connected to the return oil passage 300, and a load feedback chamber 1124 connected to the load feedback oil passage 400. The proportional control valve core 111 is movably disposed within the proportional control valve chamber 112. The inlet chamber 1121 and the load feedback chamber 1124 are respectively disposed at opposite ends of the proportional control valve core 111, so that the proportional control valve core 111 can move according to the pressure difference between the oil pressure in the inlet chamber 1121 and the oil pressure in the load feedback chamber 1124 to control the communication state between the control chamber 1122 and the return oil chamber 1123. A control spring 113 is disposed within the load feedback chamber 1124, which can drive the proportional control valve core 111 to move closer to the inlet chamber 1121. The pressure value of 113 in its initial state is the set value. When the difference between the oil pressure in the inlet chamber 1121 and the oil pressure in the load feedback chamber 1124 is less than the set pressure value of the control spring 113, the oil pressure in the load feedback chamber 1124 will push the proportional control valve core 111 to move to the left, so that the control chamber 1122 and the return chamber 1123 can be connected, realizing the connection between the pilot oil circuit 200 and the return oil circuit 300. The smaller the difference between the oil pressure in the inlet chamber 1121 and the oil pressure in the load feedback chamber 1124, the greater the displacement of the proportional control valve core 111 to the left, resulting in a larger valve opening of the control valve 11. The pilot oil circuit 200 will unload more pressure through the return oil circuit 300, thereby making the control pressure of the pilot oil circuit 200 on the main valve of the corresponding working link of the actuator smaller, and the valve opening of the main valve core of the working link smaller, further enhancing the adaptive flow distribution effect of the flow adaptive load feedback multi-way valve of the present invention.

[0058] See Figure 3The proportional control valve core 111 includes a control sealing part 1111, a channel part 1112, and a valve core positioning part 1113 arranged in sequence. The control sealing part 1111 is located between the oil inlet chamber 1121 and the control chamber 1122 to form a seal between the oil inlet chamber 1121 and the control chamber 1122. The channel part 1112 and the inner wall of the proportional control valve chamber 112 form an oil passage connecting to the return oil chamber 1123. One end of the control sealing part 1111 connected to the channel part 1112 is a valve core opening section 1114. The valve core opening section 1114 moves into the control chamber 1122 so that the oil passage is connected to the control chamber 1122. The difference between the oil pressure in the oil inlet chamber 1121 and the oil pressure in the load feedback chamber 1124 is... When the pressure is equal to the set pressure of the control spring 113, the valve core opening section 1114 is preferably at the critical position at the right end of the control chamber 1122. When the difference is less than the set pressure, when the proportional control valve core 111 moves, the valve core opening section 1114 can move into the control chamber 1122 in time, and the response speed of the flow adaptive adjustment is rapid. The valve core positioning part 1113 is located between the oil return chamber 1123 and the load feedback chamber 1124 to form a seal between the oil return chamber 1123 and the load feedback chamber 1124. A portion of the outer peripheral wall of the valve core positioning part 1113 is in contact with a portion of the inner peripheral wall of the proportional control valve chamber 112, and a guide structure is formed between the two to guide the movement direction of the proportional control valve core 111.

[0059] As a specific embodiment of the flow adaptive load feedback multi-way valve of the present invention, see [link to relevant documentation]. Figure 3The valve core positioning part 1113 near the load feedback chamber 1124 forms a spring mounting groove 1115 for mounting the control spring 113. The valve body of the control valve 11 includes a threaded sleeve 114, which is installed corresponding to the load feedback chamber 1124 so that the inner cavity of the threaded sleeve 114 communicates with the load feedback chamber 1124. A spring seat 115 is provided in the inner cavity of the threaded sleeve 114. The two ends of the control spring 113 abut against the bottom of the spring mounting groove 1115 and the side of the spring seat 115 near the load feedback chamber 1124, respectively. A pressure adjusting screw 116 is connected to the side of the spring seat 115 away from the load feedback chamber 1124. The end of the pressure adjusting screw 116 away from the spring seat 115 extends out from the threaded hole of the threaded sleeve 114. By screwing in or out the pressure adjusting screw 116, the spring seat 115 can be moved closer to or away from the control spring 113, so as to change the control spring. The set pressure value of spring 113 changes the adjustment range of the control pressure of the pilot oil circuit 200 to the working link. The pressure adjusting screw 116 can be screwed inward to reduce the control pressure earlier, or screwed outward to delay the reduction of the control pressure. For example, preferably, when two or more actuators are operating simultaneously, the pressure adjusting screw 116 is rotated one-quarter turn each time to adjust the spring seat 115 to a suitable position, thereby controlling the set pressure value of spring 113 to the required pressure value. Furthermore, a locking nut 117 is connected to the end of the pressure adjusting screw 116 extending from the threaded sleeve 114. After the pressure adjusting screw 116 is adjusted, the locking nut 117 locks the pressure adjusting screw 116 onto the threaded sleeve 114, preventing vibration or accidental activation and ensuring the normal operation of the multi-way valve of this invention. To ensure the sealing of the proportional control valve chamber 112, sealing rings are provided on both the threaded sleeve 114 and the spring seat 115.

[0060] Further, see Figure 3 The valve body is provided with an oil inlet p, a control oil port pk, a return oil port t, and a load feedback oil port ls for external connection. The oil inlet p is connected to the oil inlet chamber 1121, the control oil port pk is connected to the control chamber 1122, the return oil port t is connected to the return oil chamber 1123, and the load feedback oil port ls is connected to the load feedback chamber 1124. The oil inlet p, the control oil port pk, and the load feedback oil port ls are respectively provided with a first damping plug 118, a second damping plug 119, and a third damping plug 1110, so as to smooth out the rapid changes in hydraulic oil pressure in the oil circuit, reduce the impact of oil pressure fluctuations in the oil inlet circuit 100, the pilot circuit 200, and the load feedback circuit 400 on the operation of the control valve 11, and improve the stability of the operation of the control valve 11.

[0061] It should be noted that, see Figure 3-5 The valve core positioning part 1113 is stepped to limit the movement distance of the proportional control valve core 111. Figure 4To ensure that the proportional control valve core 111 is in the left limit position, the stepped surface of the valve core positioning part 1113 abuts against the left end face of the load feedback chamber 1124 to form a left limit structure. Figure 5 With the proportional control valve core 111 in its right extreme position, the right end face of the valve core positioning part 1113 abuts against the right end face of the threaded sleeve 114 to form a right limiting structure. In this right extreme position, to allow hydraulic oil from the load feedback oil circuit 400 to flow into the load feedback chamber 1124 through the load feedback port ls, and to apply oil pressure to the right end of the proportional control valve core 111, a cross groove 1116 is formed on the right end face of the valve core positioning part 1113. This cross groove 1116 also communicates with the load feedback port ls when the proportional control valve core 111 is in its right extreme position. Furthermore, since the valve core positioning part 1113 is stepped, its large-diameter portion divides the load feedback chamber 1124 into left and right chambers during movement. To ensure smooth movement of the proportional control valve core 111, see [reference needed]. Figure 3 A central oil hole 1117 is formed on the valve core positioning part 1113. One end of the central oil hole 1117 is connected to the cross groove 1116, and the other end is connected to the cavity part of the load feedback chamber located on the left side of the valve core positioning part 1113. This ensures that the left and right chambers of the load feedback chamber 1124 separated by the valve core positioning part 1113 are always connected to each other during the movement of the proportional control valve core 111.

[0062] Alternatively, as another specific embodiment of the proportional control valve core 111, see [link to relevant documentation]. Figure 6 The valve core positioning part 1113 is cylindrical and has no stepped structure on its outer circumference. The leftward movement distance of the proportional control valve core 111 can be limited by abutting the left end face of the control sealing part 1111 against the left inner wall of the oil inlet chamber 1121, and the rightward movement distance of the proportional control valve core 111 can be limited by abutting the right end face of the valve core positioning part 1113 against the right end face of the screw sleeve 114. Furthermore, the valve core positioning part 1113 does not divide the load feedback chamber 1124 into left and right chambers. Therefore, there is no need to set a central oil hole 1117 in the valve core positioning part 1113, thereby simplifying the structural complexity of the proportional control valve core 111 and facilitating its processing and manufacturing.

[0063] Taking a truck crane as an example, see Figure 1Each working link includes a secondary lifting link 2, a main lifting link 3, a luffing link 4, and a telescopic link 5 arranged sequentially. The main valve of each working link is connected to a pressure compensation valve to maintain a constant hydraulic oil pressure difference between the input and output of the main valve of each working link. Each working link's main valve has a pilot proportional valve at both ends to control the position of the main valve spool, and the pilot proportional valve is connected to the pilot oil circuit 200. When multiple actuators are operating at maximum pressure, the control valve 11 monitors the pressure difference between the oil pressure in the inlet oil circuit 100 and the oil pressure in the load feedback oil circuit 400. When the pressure difference is less than a set value, the pilot oil circuit 200 is connected to the return oil circuit 300 to relieve pressure, thereby reducing the control pressure on the main valve spool of the working link through the pilot proportional valve in the pilot oil circuit 200, reducing the main valve opening, and reducing the flow rate into the actuator. Specifically, taking the secondary lifting link 2 as an example, see... Figure 1 The auxiliary lifting unit 2 includes an auxiliary lifting pressure compensation valve 21, an auxiliary lifting main valve core 23, a first auxiliary lifting pilot proportional valve 24, and a second auxiliary lifting pilot proportional valve 25. The first auxiliary lifting pilot proportional valve 24 is connected to the pilot oil circuit 200 and the upper end of the auxiliary lifting main valve 23, respectively. Figure 1 (As shown in the diagram), the second auxiliary lifting pilot proportional valve 25 is connected to the lower end of the pilot oil circuit 200 and the auxiliary lifting main valve core 23 respectively. Figure 1 (As shown in the diagram), the connection status of the first auxiliary lifting pilot proportional valve 24 and the second auxiliary lifting pilot proportional valve 25 with the pilot oil circuit 200 is controlled by electromagnetic control, thereby controlling the movement of the auxiliary lifting main valve core 23 and switching it to different working positions. The pressure compensation valve 21 is connected to the auxiliary lifting main valve core 23. The oil inlet circuit 100 inputs hydraulic oil into the pressure compensation valve 21 through the valve port of the auxiliary lifting main valve core 23. The pressure compensation valve 21 then inputs the compensated hydraulic oil back into the auxiliary lifting main valve core 23 to supply it to the working oil port, ensuring that the pressure difference before and after the auxiliary lifting main valve core 23 is constant. This ensures that the flow rate from the auxiliary lifting main valve core 23 to the working oil port is controlled only by the valve opening of the auxiliary lifting main valve core 23. When the actuators connected to the auxiliary lifting linkage 2 and other working linkages operate together... If the maximum load pressure increases or the total inlet pressure of the inlet oil circuit 100 decreases, causing the pressure difference between the oil in the inlet oil circuit 100 and the load feedback oil circuit 400 to be less than the set pressure of the control valve 11, the pilot oil circuit 200 will release pressure from the return oil circuit 300. The pilot oil circuit 200 will reduce the control pressure on the auxiliary lifting main valve core 23 through the first auxiliary lifting pilot proportional valve 24 or the second auxiliary lifting pilot proportional valve 25, resulting in a decrease in the valve opening of the auxiliary lifting main valve core 23. This will reduce the input and output flow of the auxiliary lifting main valve core 23, establish a pressure difference across the main valve port, and thus avoid insufficient flow of the pressure compensation valve, full opening of the pressure compensation valve, and sudden disappearance of actuator pressure, ensuring normal and stable operation of the actuator.

[0064] As a specific embodiment of the flow adaptive load feedback multi-way valve of the present invention, see [link to relevant documentation]. Figure 1 The auxiliary hoisting unit 2 includes an auxiliary hoisting pressure compensation valve 21 and a first shuttle valve 22; the main hoisting unit 3 includes a main hoisting pressure compensation valve 31 and a second shuttle valve 32; the luffing unit 4 includes a luffing pressure compensation valve 41 and a third shuttle valve 42; and the telescopic unit 5 includes a telescopic pressure compensation valve 51. The output ports of the telescopic pressure compensation valve 51 and the luffing pressure compensation valve 41 are respectively connected to the first comparison port and the second comparison port of the third shuttle valve 42. The output ports of the third shuttle valve 42 and the main hoisting pressure compensation valve 31 are respectively connected to the first comparison port and the second comparison port of the second shuttle valve 32. The output port of the second shuttle valve 32 is connected to the auxiliary hoisting unit 22. The output port of the pressure compensation valve 21 is connected to the first comparison port and the second comparison port of the first shuttle valve 22. The output port of the first shuttle valve 22 is connected to the load feedback oil circuit 400. Through the combined left and right movements of the first shuttle valve 22, the second shuttle valve 32 and the third shuttle valve 42, the maximum load pressure in the auxiliary lifting link 2, the main lifting link 3, the luffing link 4 and the telescopic link 5 can be introduced into the load feedback oil circuit 400. This allows the oil inlet circuit 100 to be compared with the maximum load pressure, thereby controlling the valve opening of each working link to adjust the input and output flow of the main valve of each working link, achieving adaptive flow regulation, and ensuring stable operation of the actuator.

[0065] More specifically, the spring control chambers of the auxiliary lifting pressure compensation valve 21, main lifting pressure compensation valve 31, luffing pressure compensation valve 41, and telescopic pressure compensation valve 51 are all connected to the load feedback oil circuit 400. This ensures that when the maximum load pressure changes among the auxiliary lifting link 2, main lifting link 3, luffing link 4, and telescopic link 5, each pressure compensation valve maintains a constant pressure difference across the main valve of its corresponding working link. This allows the output flow of each working link to change proportionally, ensuring stable operation of each actuator and preventing inconsistent or uncoordinated operating speeds. Furthermore, each working link's pressure compensation valve is equipped with a throttling orifice on the connection between its oil circuit and the load feedback oil circuit 400 to prevent fluctuations in the load pressure of each working link from affecting the operation of its pressure compensation valve.

[0066] See Figure 1 The oil inlet link 1 includes a pilot pressure reducing valve 12. The oil inlet circuit 100 is connected to the pilot oil circuit 200 through the pilot pressure reducing valve 12. The pilot pressure reducing valve 12 reduces the oil inlet pressure of the oil inlet circuit 100 to the required pilot pressure, thereby avoiding excessive oil pressure and damage to the pilot components.

[0067] As a preferred embodiment of the flow - adaptive load - feedback multi - way valve of the present invention, the inlet connection 1 includes a pilot relief valve 13. The pilot relief valve 13 is respectively connected to the pilot oil circuit 200 and the oil return circuit 300, so as to be able to relieve pressure in time when the pressure in the pilot oil circuit 200 is too high. And the output port of the pilot relief valve 13 is connected to the spring control chamber of the pilot reducing valve 12, so as to ensure that the oil pressure in the pilot oil circuit 200 is within a stable range under the combined action of the pilot relief valve 13 and the pilot reducing valve.

[0068] The technical solution of the present invention will be described below in combination with the above - mentioned relatively preferred technical features:

[0069] See Figure 1-3 , each working connection of the flow - adaptive load - feedback multi - way valve of the present invention includes a sub - hoisting connection 2, a main - hoisting connection 3, a luffing connection 4, and a telescopic connection 5. When the actuators connected to the above - mentioned working connections are all operating, after the load pressures of each working connection are compared by the first shuttle valve 22, the second shuttle valve 32, and the third shuttle valve 42, the maximum load pressure is introduced into the load - feedback oil circuit 400. By comparing the oil pressure in the load - feedback oil circuit 400 with the oil pressure in the inlet oil circuit 100 through the control valve 11, the control pressure of the pilot oil circuit 200 on the main valve of each working connection is changed to synchronously adjust the flow rate entering the actuator. Among them, the pressure of the oil in the inlet oil circuit 100 entering the inlet chamber 1121 acting on the left end of the proportional control spool 111 ( Figure 3 the orientation shown) is P1, and the pressure of the load - feedback oil circuit 400 entering the load - feedback chamber 1124 acting on the right end of the proportional control spool 111 ( Figure 3 the orientation shown) is P2, and the set pressure of the control spring 113 is P0. The pressure difference value at both ends of the proportional control spool 111 in the initial state has been set and is a fixed value after being set, that is, the force condition at the initial position of the proportional control spool 111 is P1 - P2 = P0.

[0070] When two or more actuators are working at the maximum pressure, P1 - P2 < P0, which will cause the hydraulic pressure acting on the right side of the proportional control spool 111 to be less than the sum of the hydraulic pressure acting on the left side and the set pressure of the control spring 113, resulting in the proportional control spool 111 moving to the left, making the valve opening section 1114 move into the control chamber 1122, connecting the control chamber 1122 with the oil return chamber, so that the pilot oil circuit 200 is connected to the oil return circuit 300, and part of the pressure of the pilot oil circuit 200 is relieved. The control pressure of the pilot oil circuit 200 on the main valve of each working connection is reduced, causing the valve opening of the main valve to become smaller, so as to automatically stabilize the pressure difference before and after the main valve port under the condition of reduced flow rate, achieve the adaptive effect of flow distribution, prevent the phenomenon that the pressure - compensation valve corresponding to the working connection opens completely due to insufficient flow rate, and the pressure of the actuator suddenly disappears, and enable the actuator to operate normally and stably.

[0071] When the oil pressure in the inlet oil circuit 100 increases or the maximum load pressure decreases, the value of P1-P2 will increase, causing the proportional control valve core 111 to move to the right. The opening size between the valve core opening section 1114 and the control chamber 1122 will decrease or completely close, thereby reducing the pressure discharged from the return oil circuit 300 by the pilot oil circuit 200. The control pressure of the pilot oil circuit 200 on the main valve of each working link will increase again, and the valve opening of the main valve will increase. Under high flow conditions, it can automatically stabilize the pressure difference across the main valve orifice, ensuring the stable operation of the multi-way valve.

[0072] Through the above technical solution, the adaptive load feedback multi-way valve of the present invention can realize the linkage of the oil inlet circuit 100, the pilot oil circuit 200 and the load feedback oil circuit 400, so as to ensure that the flow can be reasonably allocated and the actuator can be stably operated when the multi-way valve performs compound actions.

[0073] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0074] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0075] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A flow-adaptive load feedback multi-way valve, characterized in that, It includes an oil inlet line (1), multiple sequentially arranged working lines, an oil inlet circuit (100), a pilot oil circuit (200), a return oil circuit (300), and a load feedback oil circuit (400). The oil inlet circuit (100) connects the oil inlet line (1) to each of the working lines to supply oil. The return oil circuit (300) connects the oil inlet line (1) to each of the working lines to return oil. The pilot oil circuit (200) connects each of the working lines to control the valve opening of the main valve core of each working line. The output pressure of the main valve core of each working line can be introduced into the load feedback oil circuit (400). The oil inlet line (1) is equipped with a control valve (11), which is connected to the oil inlet line (100) and the pilot oil circuit (300). The system includes an inlet oil passage (100), a pilot oil passage (200), a return oil passage (300), and a load feedback oil passage (400). The valve core of the control valve (11) can control the connection state between the pilot oil passage (200) and the return oil passage (300). The hydraulic oil in the inlet oil passage (100) and the hydraulic oil in the load feedback oil passage (400) act on the opposite ends of the valve core of the control valve (11) respectively, so as to control the connection state between the pilot oil passage (200) and the return oil passage (300) according to the pressure difference between the oil pressure in the inlet oil passage (100) and the oil pressure in the load feedback oil passage (400), thereby controlling the valve opening of the main valve core of each working link. The control valve (11) is a proportional control valve. The valve body of the proportional control valve includes a proportional control valve core (111) and a proportional control valve chamber (112). The proportional control valve chamber (112) includes an inlet chamber (1121) connected to the inlet oil circuit (100), a control chamber (1122) connected to the pilot oil circuit (200), a return oil chamber (1123) connected to the return oil circuit (300), and a load feedback chamber (1124) connected to the load feedback oil circuit (400). The proportional control valve core (111) is movably disposed in the proportional control valve chamber (112). Inside, the oil inlet chamber (1121) and the load feedback chamber (1124) are respectively disposed at opposite ends of the proportional control valve core (111), so that the proportional control valve core (111) can move according to the pressure difference between the oil pressure in the oil inlet chamber (1121) and the oil pressure in the load feedback chamber (1124) to control the communication state between the control chamber (1122) and the return chamber (1123). The load feedback chamber (1124) is provided with a control spring (113) that can drive the proportional control valve core (111) to move closer to the oil inlet chamber (1121).

2. The flow adaptive load feedback multi-way valve according to claim 1, characterized in that, The proportional control valve core (111) includes a control sealing part (1111), a channel part (1112), and a valve core positioning part (1113) arranged in sequence. The control sealing part (1111) is located between the oil inlet chamber (1121) and the control chamber (1122) to form a seal between the oil inlet chamber (1121) and the control chamber (1122). The channel part (1112) forms a connection with the inner wall of the proportional control valve chamber (112) to communicate with the return oil chamber (1123). The oil passage has a control sealing part (1111) connected to the passage part (1112) at one end, which is a valve core opening section (1114). The valve core opening section (1114) moves into the control chamber (1122) so that the oil passage communicates with the control chamber (1122). The valve core positioning part (1113) is located between the return oil chamber (1123) and the load feedback chamber (1124) to form a seal between the return oil chamber (1123) and the load feedback chamber (1124).

3. The flow adaptive load feedback multi-way valve according to claim 2, characterized in that, The valve core positioning part (1113) near the load feedback chamber (1124) forms a spring mounting groove (1115) for mounting the control spring (113). The valve body of the control valve (11) includes a threaded sleeve (114), which is installed corresponding to the load feedback chamber (1124) so ​​that the inner cavity of the threaded sleeve (114) communicates with the load feedback chamber (1124). A spring seat (115) is provided in the inner cavity of the threaded sleeve (114), and the two ends of the control spring (113) abut against the bottom of the spring mounting groove (1115). The spring seat (115) is located near the load feedback chamber (1124), and the side of the spring seat (115) away from the load feedback chamber (1124) is connected to a pressure regulating screw (116). The end of the pressure regulating screw (116) away from the spring seat (115) extends out from the threaded hole of the screw sleeve (114). By screwing in or out the pressure regulating screw (116), the spring seat (115) can be moved closer to or away from the control spring (113). A locking nut (117) is connected to the end of the pressure regulating screw (116) extending from the screw sleeve (114).

4. The flow adaptive load feedback multi-way valve according to claim 1, characterized in that, The valve body is provided with an oil inlet (p), a control oil port (pk), a return oil port (t), and a load feedback oil port (ls) connected to the outside. The oil inlet (p) is connected to the oil inlet chamber (1121), the control oil port (pk) is connected to the control chamber (1122), the return oil port (t) is connected to the return oil chamber (1123), and the load feedback oil port (ls) is connected to the load feedback chamber (1124). The oil inlet (p), the control oil port (pk), and the load feedback oil port (ls) are respectively provided with a first damping plug (118), a second damping plug (119), and a third damping plug (1110).

5. The flow adaptive load feedback multi-way valve according to claim 1, characterized in that, Each of the working links includes a secondary hoisting link (2), a main hoisting link (3), a luffing link (4), and a telescopic link (5) arranged in sequence. The main valve of each working link is connected to a pressure compensation valve to control the hydraulic oil pressure difference between the input and output of the main valve core of each working link to be constant. Each working link has a pilot proportional valve at both ends of the main valve to control the position state of the main valve core. The pilot proportional valve is connected to the pilot oil circuit (200).

6. The flow adaptive load feedback multi-way valve according to claim 5, characterized in that, The auxiliary lifting unit (2) includes an auxiliary lifting pressure compensation valve (21) and a first shuttle valve (22). The main lifting unit (3) includes a main lifting pressure compensation valve (31) and a second shuttle valve (32). The luffing unit (4) includes a luffing pressure compensation valve (41) and a third shuttle valve (42). The telescopic unit (5) includes a telescopic pressure compensation valve (51). The output ports of the telescopic pressure compensation valve (51) and the luffing pressure compensation valve (41) are respectively connected to the first comparison port and the second comparison port of the third shuttle valve (42). The output ports of the third shuttle valve (42) and the main lifting pressure compensation valve (31) are respectively connected to the first comparison port and the second comparison port of the second shuttle valve (32). The output ports of the second shuttle valve (32) and the auxiliary lifting pressure compensation valve (21) are respectively connected to the first comparison port and the second comparison port of the first shuttle valve (22). The output port of the first shuttle valve (22) is connected to the load feedback oil circuit (400).

7. The flow adaptive load feedback multi-way valve according to claim 6, characterized in that, The spring control chambers of the auxiliary lifting pressure compensation valve (21), the main lifting pressure compensation valve (31), the luffing pressure compensation valve (41), and the telescopic pressure compensation valve (51) are all connected to the load feedback oil circuit (400), and each working pressure compensation valve is provided with a throttling orifice on the oil circuit connecting it to the load feedback oil circuit (400).

8. The flow adaptive load feedback multi-way valve according to claim 1, characterized in that, The oil inlet link (1) includes a pilot pressure reducing valve (12), and the oil inlet line (100) is connected to the pilot oil line (200) through the pilot pressure reducing valve (12).

9. The flow adaptive load feedback multi-way valve according to claim 8, characterized in that, The oil inlet assembly (1) includes a pilot relief valve (13), which is connected to the pilot oil circuit (200) and the return oil circuit (300) respectively. The output port of the pilot relief valve (13) is connected to the spring control chamber of the pilot pressure reducing valve (12).

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