CN113931891A

CN113931891A - Load port independent control load sensitive multi-way valve and hydraulic system

Info

Publication number: CN113931891A
Application number: CN202111142764.0A
Authority: CN
Inventors: 罗炎热; 吴光镇; 蒋淋
Original assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Changde Zhonglian Zhongke Hydraulic Co ltd
Priority date: 2021-09-28
Filing date: 2021-09-28
Publication date: 2022-01-14
Anticipated expiration: 2041-09-28
Also published as: CN113931891B

Abstract

The invention relates to a hydraulic multi-way valve and discloses a load-port independent control load sensitive multi-way valve which comprises a valve body, wherein an oil inlet, an oil return port, a first working oil port and a second working oil port which are externally connected are arranged on the valve body, a first control valve cavity and a second control valve cavity are arranged in the valve body, an A port main control valve structure and an A port pressure compensation valve structure are arranged in the first control valve cavity so as to independently control oil supply and oil return of the first working oil port and perform oil supply pressure compensation according to the pressure of the first working oil port, and a B port main control valve structure and a B port pressure compensation valve structure are arranged in the second control valve cavity so as to independently control oil supply and oil return of the second working oil port and perform oil supply pressure compensation according to the pressure of the second working oil port. The load port independent control load sensitive multi-way valve can independently control two working oil ports, and has the advantages of simple structure, convenience in use and low manufacturing cost. The invention also provides a hydraulic brake system.

Description

Load port independent control load sensitive multi-way valve and hydraulic system

Technical Field

The invention relates to a hydraulic multi-way valve, in particular to a load port independent control load sensitive multi-way valve. The invention also relates to a hydraulic system.

Background

In a hydraulic system, the elements used to control or regulate the flow direction, pressure and flow of hydraulic oil are collectively referred to as hydraulic valves. The hydraulic valve is widely applied to a hydraulic system, and the multiway valve is a hydraulic valve for controlling the flow direction of hydraulic oil and is commonly used for controlling the movement direction of a hydraulic actuator in the hydraulic system. The load-sensitive multi-way valve is a multi-way valve which can reduce the influence of load pressure and keep the flow in a liquid path relatively stable.

The main valve core of the traditional load-sensitive multi-way valve adopts one main valve core to control the flow direction of pressure oil, and the change of the motion direction of an actuating mechanism connected to a load port of the main valve core is realized by reversing control of the valve core. Because a main valve core is adopted, the oil inlet channel and the oil return channel are controlled by the same valve core, the opening displacement of the throttling groove on the valve core is in equidirectional linkage, and the area of the throttling groove is simultaneously increased or reduced. In order to realize the matching of oil inlet and oil return, different oil inlet and oil return throttling grooves are designed according to different working conditions and different flow rates to meet requirements, even auxiliary elements such as a balance valve, a one-way throttling valve, a back pressure valve and the like are required to be added in a system to increase oil return back pressure, otherwise, the operation of a host machine is unstable, and even the host machine stalls. However, the addition of numerous additional valves to the system tends to increase the power consumption and cost of the host.

The load port independent control technology controls the oil inlet and the oil return of the executing mechanism respectively by arranging two independent main valve cores, and effectively solves the problem of poor matching of the oil inlet and the oil return of the traditional multi-way valve. The existing load port independent control double-spool multi-way valve generally comprises a main valve body, two main valve spool assemblies, a pilot reversing valve assembly, a signal acquisition part and the like, wherein a pressure sensor and a temperature sensor are embedded in the main valve body and used for acquiring pressure signals and temperature change signals, a displacement sensor is integrated on the main valve spool and used for acquiring spool displacement signals, and the displacements of the two main valve spools can be respectively controlled by controlling the input signal strength and the input signal mode of the pilot reversing valve assembly, so that the oil inlet, the oil return pressure and the flow required by the system are respectively controlled.

The flow and pressure requirements of the existing load port independent control double-valve-core multi-way valve are compared and analyzed through data collected by pressure, flow and displacement sensors, and the flow and pressure required by a system are output through program operation. The process system is controlled by an electric control system, and the difficulty of system debugging and control is greatly increased; due to the integration of a plurality of sensors, the requirements of manufacturing, installing, controlling precision and the like of the valve body and the valve core are greatly increased, and meanwhile, the multi-way valve has poor pollution resistance, poor maintainability and high manufacturing cost, and the market acceptance is influenced.

Disclosure of Invention

The invention aims to solve the technical problem of providing a load-port independent control load-sensitive multi-way valve which can independently control oil inlet and oil return paths, and has the advantages of simple structure, convenience in use and low manufacturing cost.

The invention further aims to solve the technical problem of providing a hydraulic system which can independently control the oil inlet and oil return states of an actuating mechanism and has the advantages of simple structure, good maintenance performance and low manufacturing cost.

In order to solve the above technical problems, the present invention provides a load-port independent control load-sensitive multi-way valve, including a valve body and a valve structure disposed on the valve body, wherein the valve body is provided with an oil inlet, an oil return port, a first working oil port and a second working oil port, which are connected to each other, the valve body is provided with a first control valve cavity and a second control valve cavity, the first control valve cavity is provided with an a-port main control valve structure and an a-port pressure compensation valve structure, so as to control hydraulic oil at the oil inlet to be delivered to the first working oil port after pressure compensation, or hydraulic oil at the first working oil port is unloaded through the oil return port, and the a-port pressure compensation valve structure is controlled to perform pressure compensation according to the pressure at the first working oil port, the second control valve cavity is provided with a B-port main control valve structure and a B-port pressure compensation valve structure, the hydraulic oil of the oil inlet can be controlled to be conveyed to the second working oil port after pressure compensation, or the hydraulic oil of the second working oil port is unloaded through the oil return port, and the pressure compensation valve structure of the port B can be controlled to perform pressure compensation according to the pressure of the second working oil port.

Preferably, the valve body is further provided with a first port A proportional valve interface, a second port A proportional valve interface, a first port B proportional valve interface and a second port B proportional valve interface, a first port A proportional pressure reducing valve can be installed through the first port A proportional valve interface to convert the hydraulic oil of the oil inlet into pilot control hydraulic oil to be conveyed to one side control end of the port A main control valve structure, a second port A proportional pressure reducing valve can be installed through the second port A proportional valve interface to convert the hydraulic oil of the oil inlet into pilot control hydraulic oil to be conveyed to the other side control end of the port A main control valve structure, a first port B proportional pressure reducing valve can be installed through the first port B proportional valve interface to convert the hydraulic oil of the oil inlet into pilot control hydraulic oil to be conveyed to one side control end of the port B main control valve structure, and a second B port proportional pressure reducing valve can be installed through the second B port proportional valve interface so as to convert the hydraulic oil of the oil inlet into pilot control hydraulic oil and convey the pilot control hydraulic oil to the other side control end of the B port main control valve structure. In the preferred technical scheme, the first A-port proportional pressure reducing valve and the second A-port proportional pressure reducing valve which are arranged on the first A-port proportional valve interface and the second A-port proportional valve interface can accurately control the position of a valve core of the A-port main control valve structure through the control ends at two sides of the A-port main control valve structure, so that the flow direction and the flow rate of hydraulic oil passing through the A-port main control valve structure are accurately controlled; through installing first B mouthful proportional pressure reducing valve and the proportional pressure reducing valve of second B mouth on first B mouthful proportional valve interface and the proportional valve interface of second B mouth and can pass through the case position of the both sides control end accurate control B mouth main control valve structure of B mouth main control valve structure to the flow direction and the flow of the hydraulic oil of accurate control through B mouth main control valve structure. The control precision of the load sensitive multi-way valve independently controlled by the load port is higher.

Preferably, the first port a proportional valve interface, the second port a proportional valve interface, the first port B proportional valve interface, and the second port B proportional valve interface each include an oil inlet duct, an oil return duct, and a control duct, the oil return duct is communicated with the oil inlet, the oil return duct is communicated with the oil return port, and the control ducts are respectively communicated with control ends on two sides of the port a main control valve structure and the port B main control valve structure. In the preferred technical scheme, pressure liquid at an oil inlet can be introduced through the oil inlet duct and conveyed to the proportional pressure reducing valve, pilot control hydraulic oil with certain pressure is formed under the control of a proportional electric control signal, and the pilot control hydraulic oil is conveyed to a control end of the main control valve structure through the control oil duct to control the reversing and valve core displacement of the main control valve structure. The pilot control hydraulic oil at the control end of the main control valve structure can be unloaded through the oil return passage, so that the main control valve structure is reset.

Preferably, the port a pressure compensation valve structure is arranged inside the port a main control valve structure; the port B pressure compensation valve structure is arranged inside the port B main control valve structure. Through this preferred technical scheme, can make to form the linkage between pressure compensation valve structure and the main control valve structure, simplify the form of valve structure to make the setting of valve structure compacter.

Further preferably, the port a main control valve structure comprises a port a main control valve core, a port a connecting spring seat, a port a return spring seat and a port a return spring, a valve core cavity with an open end is arranged in the port a main control valve core, the port a connecting spring seat is connected to the open end of the valve core cavity of the port a main control valve core, the port a return spring seat is sleeved on the port a main control valve core, the port a return spring is arranged between the port a return spring seat and the port a connecting spring seat, the port a pressure compensation valve structure is arranged in the valve core cavity of the port a main control valve core, one end of the port a connecting spring seat of the first control valve cavity is communicated with the port a proportional valve interface, and the other end of the port a connecting spring seat is communicated with the port a proportional valve interface of the second port a proportional valve; the port B main control valve structure comprises a port B main control valve core, a port B connecting spring seat, a port B resetting spring seat and a port B resetting spring, a valve core cavity with an open end is arranged in the port B main control valve core, the port B connecting spring seat is connected with the open end of the valve core cavity of the port B main control valve core, the port B resetting spring seat is sleeved on the port B main control valve core, the port B resetting spring is arranged between the port B resetting spring seat and the port B connecting spring seat, the port B pressure compensation valve structure is arranged in the valve core cavity of the port B main control valve core, the second control valve cavity is provided with one end where the port B connecting spring seat is positioned and communicated with the first port B proportional valve interface, and the other end of the port B main control valve cavity is communicated with the second port B proportional valve interface. Through this preferred technical scheme, main control case can move in the control valve chamber under the effect of control valve chamber both ends guide hydraulic oil to switch the valve position of main control case and control the displacement of main control case, thereby carry hydraulic oil to the working oil mouth through the inlet, perhaps through the hydraulic oil off-load of oil return opening with the working oil mouth, and can control the flow of hydraulic oil. The return spring can promote the return of the main control valve core.

Furthermore, the port A pressure compensation valve structure comprises a port A pressure compensation valve core and a port A pressure compensation spring, the port A pressure compensation valve core is arranged in a valve core cavity of the port A main control valve core, the port A pressure compensation spring is arranged between the port A pressure compensation valve core and the port A connecting spring seat, and the port A pressure compensation valve core can move in the valve core cavity of the port A main control valve core; the port B pressure compensation valve structure comprises a port B pressure compensation valve core and a port B pressure compensation spring, the port B pressure compensation valve core is arranged in a valve core cavity of the port B main control valve core, the port B pressure compensation spring is arranged between the port B pressure compensation valve core and the port B connecting spring seat, and the port B pressure compensation valve core can move in the valve core cavity of the port B main control valve core. In the preferred technical scheme, the output pressure of the pressure compensation valve structure can be controlled by moving the pressure compensation valve core in the valve core cavity of the main control valve core, and the pressure compensation can be performed on the hydraulic oil output by the main control valve structure.

Specifically, the first control valve cavity and the second control valve cavity respectively comprise a spring cavity, a load feedback cavity, a pressure cavity, a working cavity, an oil return cavity and a pilot control cavity, the spring cavity is communicated with the first port A proportional valve interface or the first port B proportional valve interface, the load feedback cavity is communicated with a load feedback channel, the pressure cavity is communicated with the oil inlet, the working cavity is communicated with the first working oil port or the second working oil port, the oil return cavity is communicated with the oil return port, the pilot control cavity is communicated with the second port A proportional valve interface or the second port B proportional valve interface, the port A main control valve core and the port B main control valve core are respectively provided with a guide rail groove, a Ls signal hole, a pressure cavity, a working cavity oil saving groove and an oil return cavity throttling groove which are communicated with the respective valve core cavities, and the guide rail groove is connected with the Ls signal hole, the pressure compensation valve core of the port A and the pressure compensation valve core of the port B are respectively provided with an oil outlet throttling groove, an oil inlet hole and a guide hole, and the oil outlet throttling groove and the oil inlet hole are communicated with the oil through hole arranged on one side of the valve core; the port A main control valve core and the port B main control valve core can move in the first control valve cavity and the second control valve cavity respectively, so that when the port A main control valve core or the port B main control valve core is in a middle position, the pressure cavity is not communicated with the working cavity, when the port A main control valve core or the port B main control valve core is in a working position, the Ls signal hole is communicated with the load feedback cavity, the pressure cavity oil saving groove is communicated with the pressure cavity, the working cavity oil saving groove is communicated with the working cavity, and when the port A main control valve core or the port B main control valve core is in a drainage position, the oil return cavity throttling groove is communicated with the working cavity and the oil return cavity simultaneously; the port A pressure compensation valve core and the port B pressure compensation valve core are respectively arranged in the valve core cavities of the port A main control valve core and the port B main control valve core, so that the oil inlet hole can be communicated with the Ls signal hole and the pressure cavity oil saving groove, the oil outlet throttling groove is communicated with the working cavity oil saving groove, and the port A pressure compensation valve core and the port B pressure compensation valve core can be respectively arranged in the valve core cavities of the port A main control valve core and the port B main control valve core, so that the flow area between the oil outlet throttling groove and the working cavity oil saving groove can be adjusted. Through this preferred technical scheme, can be through the removal of main control case in the control valve intracavity, switch into the working chamber and be linked together with the pressure chamber, perhaps with returning oil chamber and being linked together to control hydraulic oil and follow the notch size in the case chamber that the pressure chamber got into main control case, the notch size that the case chamber got into the working chamber from main control case, and the notch size that gets into back oil chamber from the working chamber, with the flow that control hydraulic oil got into the working chamber from the pressure chamber, and the flow that gets into back oil chamber from the working chamber. Through the removal of the pressure compensation valve core in the valve core chamber of the main control valve core, the pressure compensation is carried out on the hydraulic oil entering the working chamber from the pressure chamber, so that the flow of the hydraulic oil entering the working chamber from the pressure chamber is only related to the size of the notch of the oil saving groove of the pressure chamber and is unrelated to the pressure of the hydraulic oil in the pressure chamber.

Preferably, the valve body comprises a main valve body, a first end cover and a second end cover, the first end cover and the second end cover are respectively installed on two sides of the main valve body, the main body part of the first control valve cavity and the main body part of the second control valve cavity are located in the main valve body, one end of the first control valve cavity is located in the first end cover, one end of the second control valve cavity is located in the second end cover, the first end cover is provided with a first port A proportional valve interface and a second port A proportional valve interface, and the second end cover is provided with a first port B proportional valve interface and a second port B proportional valve interface. In the preferred technical scheme, the first end cover and the second end cover are arranged to facilitate the processing of the first control valve cavity, the second control valve cavity and the internal oil duct, facilitate the installation of the A port main control valve core and the B port main control valve core in the first control valve cavity and the second control valve cavity, and facilitate the maintenance of the load port independent control load sensitive multi-way valve.

Preferably, the valve body is further provided with an a-port secondary overflow valve interface and a B-port secondary overflow valve interface, the a-port secondary overflow valve interface is arranged between the first working oil port and the oil return port, and the a-port secondary overflow valve can be mounted through the a-port secondary overflow valve interface so as to discharge the first working oil port when the pressure of the first working oil port reaches a set pressure; the port B secondary overflow valve interface is arranged between the second working oil port and the oil return port, and the port B secondary overflow valve can be installed through the port B secondary overflow valve interface so as to discharge the second working oil port when the pressure of the second working oil port reaches a set pressure. In this preferred technical scheme, through installing the overflow valve at A mouthful secondary overflow valve interface and B mouthful secondary overflow valve interface, can carry out the secondary overflow to the hydraulic oil of first working fluid port and/or second working fluid port to the upper limit of the hydraulic oil pressure of restriction first working fluid port and second working fluid port prevents the unusual rising of first working fluid port and second working fluid port hydraulic oil pressure.

Preferably, the valve body is further provided with a load feedback port connected with the outside, the first control valve cavity and the second control valve cavity both comprise load feedback cavities, and the load feedback ports are communicated with the load feedback cavities of the first control valve cavity and the second control valve cavity. Through this preferred technical scheme, can carry away the load feedback pressure in the load feedback chamber through the load feedback mouth to can utilize load feedback pressure control oil feed to ally oneself with tee bend pressure compensation valve or variable pump, thereby the pressure of control oil inlet hydraulic oil realizes the sensitive function of load of oil feed pressure.

In a second aspect of the invention, a hydraulic system is disclosed which uses the load port independent control load sensitive multi-way valve provided by the first aspect of the invention.

Through the technical scheme, the load port independently controls the load sensitive multi-way valve, the first control valve cavity and the second control valve cavity are arranged, so that the A port main control valve structure and the B port main control valve structure can independently perform reversing and flow control, and the first working oil port and the second working oil port are independently controlled. Through controlling the action sequence and the output pressure of the A port main control valve structure and the B port main control valve structure, various combinations of liquid supply states of the first working oil port and the second working oil port can be realized, the control of different hydraulic actuating mechanisms is realized, and different working states of the hydraulic actuating mechanisms are formed. The main control valve structure and the pressure compensation valve structure are arranged in the same control valve cavity, so that control oil port pressure related to working port pressure can be formed, the pressure of an oil inlet is adjusted, the hydraulic oil flow of the working oil port is only controlled by the opening size of the throttling groove of the reversing control valve core, the load sensing function is realized, and the valve structure is simpler and more compact. Compared with the existing load port independent control load sensitive multi-way valve, the load port independent control load sensitive function is realized only by using the traditional hydraulic structure without arranging various sensors and electronic control circuits, the processing precision requirement of the multi-way valve is reduced, the pollution resistance of the multi-way valve is improved, the manufacturing cost is lower, the maintainability is better, and the multi-way valve is easier to produce in batches. The hydraulic system of the invention also has the advantages due to the adoption of the load port independent control load sensitive multi-way valve of the invention.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 is a schematic valve structure of one embodiment of a load port independent control load sensitive multiplex valve of the present invention;

FIG. 2 is a schematic diagram of a main valve body configuration of one embodiment of the load port independent control load sensitive multi-way valve of the present invention;

FIG. 3 is a schematic diagram of a main control spool configuration of one embodiment of the load port independent control load sensitive multi-way valve of the present invention;

fig. 4 is a schematic diagram of a pressure compensating valve core of an embodiment of the load port independent control load sensitive multi-way valve of the present invention.

Description of the reference numerals

11 main valve body 12 first end cap

13 second end cap 21A port main control valve structure

211A port main control valve core 212A port connecting spring seat

213A mouth reset spring seat 214A mouth reset spring

Pressure compensation valve core of port 221A of pressure compensation valve structure of port 22A

Main control valve structure of 222A port pressure compensation spring 23B port

231B port main control valve core 232B port connecting spring seat

233B port reset spring seat 234B port reset spring

24B port pressure compensating valve structure 241B port pressure compensating valve core

242B port pressure compensating spring 251 first a port proportional valve port

252 second port A proportional valve port 253 first port B proportional valve port

254 second B port proportional valve port 26A port secondary overflow valve port

27B-port secondary overflow valve interface 31 first A-port proportional pressure reducing valve

32 second a port proportional pressure reducing valve 33 first B port proportional pressure reducing valve

34 second B-port proportional pressure reducing valve 41A-port secondary overflow valve

42B port secondary overflow valve 101 first control valve cavity

102 second control valve chamber 141 spring chamber

142 load feedback chamber 143 pressure chamber

144 working chamber 145 scavenge chamber

146 pilot control cavity 201 working cavity fuel-saving groove

203 Ls signal hole of 202 pressure cavity oil saving groove

204 guide track groove 205 oil return cavity throttling groove

281 oil inlet oil passage 282 oil return oil passage

301 oil outlet throttling groove 302 oil inlet hole

303 oil through hole 304 positioning hole

A first working oil port and B second working oil port

Ls load feedback oil port P oil inlet

T oil return port

Detailed Description

In the present invention, unless otherwise specified, the use of the directional terms such as "left and right" to indicate the directional or positional relationship is based on the directional or positional relationship shown in the drawings and is not intended to represent the directional or positional relationship of the physical structure of the load port independent control load sensitive multiplex valve and its components.

The terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, and therefore the features defined "first", "second" may explicitly or implicitly include one or more of said features.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; either directly or indirectly through intervening media, either internally or in any combination thereof. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

As shown in fig. 1, an embodiment of the load-sensing multi-way valve with load ports independently controlled according to the present invention includes a valve body and a valve structure disposed on the valve body, wherein an oil inlet P, an oil return port T, a first working oil port a and a second working oil port B for external connection are disposed on a surface layer of the valve body, and a first control valve cavity 101 and a second control valve cavity 102 which are independent from each other are disposed inside the valve body. The first control valve cavity 101 is communicated with the oil inlet P, the oil return port T and the first working oil port a, and an a port main control valve structure 21 and an a port pressure compensation valve structure 22 are arranged in the first control valve cavity 101, wherein the a port main control valve structure 21 can move in the first control valve cavity 101, and the first working oil port a is switched to be communicated with the oil inlet P or communicated with the oil return port T through the movement of the a port main control valve structure 21. Therefore, the hydraulic oil input through the oil inlet P is conveyed to the first working oil port A, or the hydraulic oil in the first working oil port A is unloaded through the oil return port T, and the flow rate of conveying or unloading of the hydraulic oil can be controlled. The port a pressure compensating valve structure 22 can move relative to the port a main control valve structure 21 or relative to the first control valve chamber 101, thereby controlling the pressure of the hydraulic oil delivered to the first working port a and performing pressure compensation on the hydraulic oil output through the port a main control valve structure 21. The second control valve cavity 102 is communicated with the oil inlet P, the oil return port T and the second working oil port B, and a port B main control valve structure 23 and a port B pressure compensation valve structure 24 are arranged in the second control valve cavity 102, wherein the port B main control valve structure 23 can move in the second control valve cavity 102, and the second working oil port B is switched to be communicated with the oil inlet P or communicated with the oil return port T through the movement of the port B main control valve structure 23. Therefore, the hydraulic oil input through the oil inlet P is conveyed to the second working oil port B, or the hydraulic oil in the second working oil port B is unloaded through the oil return port T, and the flow rate of conveying or unloading of the hydraulic oil can be controlled. The B port pressure compensating valve structure 24 can move relative to the B port main control valve structure 23 or relative to the second control valve cavity 102, thereby controlling the pressure of the hydraulic oil delivered to the second working oil port B and performing pressure compensation on the hydraulic oil output through the B port main control valve structure 23. Because two independent main control valve structures are adopted in two independent control valve cavities to independently control the first working oil port A and the second working oil port B, the oil inlet and the oil return oil path of the working mechanism connected with the first working oil port A and the second working oil port B can be independently adjusted respectively, and the inlet and oil return motion logics of the executing mechanism can be controlled by controlling the sequence of actions and the flow size of the A port main control valve structure 21 and the B port main control valve structure 23 to obtain various combinations so as to meet different working condition requirements. Compared with the sensor and electronic control technology of the existing load port independent control double-valve-core multi-way valve, the double-valve-core multi-way valve has the advantages of simple design, compact structure, convenience in control, stable and reliable performance, energy conservation and high efficiency. Because the traditional load sensing technology is adopted, the load port independently controlled load sensing multi-way valve has relatively low requirements on the matching precision and the processing precision of parts, has stronger pollution resistance, better maintainability and low manufacturing cost, and is easier to realize batch production.

In some embodiments of the load port independent control load sensitive multi-way valve of the present invention, as shown in fig. 1, the valve body is further provided with a first port a proportional valve interface 251, a second port a proportional valve interface 252, a first port B proportional valve interface 253, and a second port B proportional valve interface 254. Typically, the first and second port a and a proportional valve interfaces 251 and 252 are provided on the side of the valve body on which the first control valve chamber 101 is located, and the first and second port B and a

proportional valve interface

253 and 254 are provided on the side of the valve body on which the second control valve chamber 102 is located. A first port A proportional pressure reducing valve 31 can be inserted into the first port A proportional valve interface 251, and the first port A proportional pressure reducing valve 31 can reduce the pressure of hydraulic oil provided by an oil inlet P under the control of an electric control signal to form pilot control hydraulic oil with set pressure, and the pilot control hydraulic oil is conveyed to a control end on one side of the port A main control valve structure 21; a second port a proportional pressure reducing valve 32 can be inserted into the second port a proportional valve interface 252, and the second port a proportional pressure reducing valve 32 can reduce the pressure of the hydraulic oil provided by the oil inlet P under the control of the electric control signal to form pilot control hydraulic oil with a set pressure, which is delivered to the control end on the other side of the port a main control valve structure 21. The port a main control valve structure 21 switches the valve position and adjusts the opening of the valve port under the action of pilot control hydraulic oil at the control ends at both sides, and controls the flow direction and the flow rate of the hydraulic oil at the first working oil port a. A first port B proportional pressure reducing valve 33 can be inserted into the first port B proportional valve interface 253, and the first port B proportional pressure reducing valve 33 can reduce the pressure of hydraulic oil provided by the oil inlet P under the control of an electric control signal to form pilot control hydraulic oil with set pressure, and the pilot control hydraulic oil is conveyed to a control end on one side of the port B main control valve structure 23; a second B-port proportional pressure reducing valve 34 can be inserted into the second B-port proportional valve interface 254, and the second B-port proportional pressure reducing valve 34 can reduce the pressure of the hydraulic oil provided by the oil inlet P under the control of an electric control signal to form pilot control hydraulic oil with set pressure, which is delivered to the control end on the other side of the B-port main control valve structure 23. The B port main control valve structure 23 switches the valve position and adjusts the opening of the valve port under the action of pilot control hydraulic oil at the control ends at both sides, and controls the flow direction and flow rate of the hydraulic oil at the second working oil port B. Because two proportional pressure reducing valves are adopted to respectively control the pilot control hydraulic oil at the control ends at two sides of the same main control valve structure, the precision of the position control of the valve core of the main control valve structure is higher, and the flow control of the working oil port is more accurate.

As one specific embodiment of the load port independent control load sensitive multi-way valve of the present aspect, as shown in fig. 1, the first port a proportional valve interface 251, the second port a proportional valve interface 252, the first port B proportional valve interface 253, and the second port B proportional valve interface 254 each include an oil inlet passage 281, an oil return passage 282, and a control passage. The oil inlet passage 281 of each proportional valve port is connected to the oil inlet P, so that high-pressure hydraulic oil input through the oil inlet P can be introduced into each proportional valve port. The oil return passage 282 of each proportional valve interface is connected to the oil return port T, so that hydraulic oil can be introduced into the oil return port T through each proportional valve interface. The control oil passage of the first port a proportional valve interface 251 is connected to one side control end of the port a main control valve structure 21, and the control oil passage of the second port a proportional valve interface 252 is connected to the other side control end of the port a main control valve structure 21, so that the port a main control valve structure 21 can be controlled by the first port a proportional pressure reducing valve 31 and the second port a proportional pressure reducing valve 32 which are respectively inserted into the first port a proportional valve interface 251 and the second port a proportional valve interface 252. The control oil passage of the first port B proportional valve interface 253 is connected to one side control end of the port B main control valve structure 23, and the control oil passage of the second port B proportional valve interface 254 is connected to the other side control end of the port B main control valve structure 23, so that the port B main control valve structure 23 can be controlled by the first port B proportional pressure reducing valve 33 and the second port B proportional pressure reducing valve 34 which are respectively inserted into the first port B proportional valve interface 253 and the second port B proportional valve interface 254.

In some embodiments of the load port independent control load sensitive multi-way valve of the present invention, as shown in fig. 1, the a port main control valve structure 21 is disposed in the first control valve cavity 101 and is movable in the first control valve cavity 101, so as to control the flow direction and flow rate of the hydraulic oil output through the a port main control valve structure 21. The port a pressure compensating valve structure 22 is provided inside the port a main control valve structure 21, is movable relative to the port a main control valve structure 21, and compensates the pressure of the hydraulic oil output through the port a main control valve structure 21. The B port main control valve structure 23 is provided in the second control valve chamber 102 and is movable within the second control valve chamber 102, thereby controlling the flow direction and flow rate of the hydraulic oil output through the B port main control valve structure 23. The B-port pressure compensating valve structure 24 is provided inside the B-port main control valve structure 23, is movable relative to the B-port main control valve structure 23, and compensates the pressure of the hydraulic oil output through the B-port main control valve structure 23.

In some embodiments of the load port independent control load sensitive multiplex valve of the present invention, as shown in fig. 1, the port a main control valve structure 21 includes a port a main control spool 211, a port a connection spring seat 212, a port a return spring seat 213, and a port a return spring 214. The port a main control valve core 211 is provided with a valve core cavity with an open end, and the port a connecting spring seat 212 is connected to the open end of the valve core cavity of the port a main control valve core 211 in a threaded connection manner to seal the opening of the valve core cavity of the port a main control valve core 211. The port a return spring seat 213 is fitted over the port a main control spool 211, and the port a return spring seat 213 can be limited by the wall portion of the first control valve chamber 101. The port a return spring 214 is disposed between the port a return spring seat 213 and the port a connection spring seat 212, and can make the port a main control spool 211 and the port a connection spring seat 212 connected thereto be located at one end (left end) of the first control valve chamber 101 where the port a connection spring seat 212 is located, in a state of being free from an external control force, by an elastic force of the port a return spring 214. The port a pressure compensating valve structure 22 is installed in a spool cavity of the port a main control spool 211 and is movable in the spool cavity of the port a main control spool 211 so as to be able to perform pressure compensation on hydraulic oil output through a valve port of the port a main control spool 211. The left end (the end where the port a connecting spring seat 212 is located) of the first control valve cavity 101 is communicated with the control oil passage of the first port a proportional valve interface 251, and the right end of the first control valve cavity 101 is communicated with the control oil passage of the second port a proportional valve interface 252, so that the position of the port a main control valve spool 211 can be controlled by the first port a proportional pressure reducing valve 31 inserted into the first port a proportional valve interface 251 and the second port a proportional pressure reducing valve 32 inserted into the second port a proportional valve interface 252. The B port main control valve structure 23 includes a B port main control spool 231, a B port connection spring seat 232, a B port return spring seat 233, and a B port return spring 234. The opening of the valve core cavity of the port B main control valve core 231 is closed by connecting the port B connecting spring seat 232 to the opening end of the valve core cavity of the port B main control valve core 231 in a threaded connection manner. The B port return spring seat 233 is sleeved on the B port main control spool 231, and the B port return spring seat 233 can be limited by the wall portion of the second control valve chamber 102. The B port return spring 234 is disposed between the B port return spring seat 233 and the B port connection spring seat 232, and can make the B port main control spool 231 and the B port connection spring seat 232 connected thereto be located at one end (right end) of the second control valve chamber 102 where the B port connection spring seat 232 is located in a state of not being subjected to an external control force by the elastic force of the B port return spring 234. The B port pressure compensating valve structure 24 is installed in a spool cavity of the B port main control spool 231 and is movable in the spool cavity of the B port main control spool 231 to be able to perform pressure compensation on hydraulic oil output through a valve port of the B port main control spool 231. The right end (the end where the B port connecting spring seat 232 is located) of the second control valve cavity 102 is communicated with the control oil passage of the first B port proportional valve interface 253, and the left end of the second control valve cavity 102 is communicated with the control oil passage of the second B port proportional valve interface 254, so that the position of the B port main control valve spool 231 can be controlled by the first B port proportional pressure reducing valve 33 inserted into the first B port proportional valve interface 253 and the second B port proportional pressure reducing valve 34 inserted into the second B port proportional valve interface 254.

In some embodiments of the load port independent control load sensitive multiplex valve of the present invention, as shown in fig. 1, the port a pressure compensating valve structure 22 includes a port a pressure compensating spool 221 and a port a pressure compensating spring 222. The port a pressure compensating spool 221 is provided in a spool chamber of the port a main control spool 211 and is movable in the spool chamber of the port a main control spool 211. The port a pressure compensating spring 222 is disposed between the port a pressure compensating spool 221 and the port a connecting spring seat 212, so that the port a pressure compensating spool 221 can be located at one end (right end) of the spool cavity of the port a main control spool 211, which is far away from the port a connecting spring seat 212, under the elastic force of the port a pressure compensating spring 222. The B port pressure compensating valve structure 24 includes a B port pressure compensating spool 241 and a B port pressure compensating spring 242. The B port pressure compensating spool 241 is provided in a spool chamber of the B port main control spool 231, and is movable in the spool chamber of the B port main control spool 231. The B port pressure compensating spring 242 is disposed between the B port pressure compensating spool 241 and the B port connecting spring seat 232, so that the B port pressure compensating spool 241 can be located at one end (left end) of the spool cavity of the B port main control spool 231, which is far away from the B port connecting spring seat 242, under the elastic force of the B port pressure compensating spring 242.

As one embodiment of the load port independent control load sensitive multi-way valve of the present invention, as shown in fig. 1 to 4, the first control valve chamber 101 and the second control valve chamber 102 each include a spring chamber 141, a load feedback chamber 142, a pressure chamber 143, a working chamber 144, a return chamber 145 and a pilot control chamber 146. The spring cavity 141 of the first control valve cavity 101 is communicated with the control oil passage of the first port A proportional valve interface 251, and the spring cavity 141 of the second control valve cavity 102 is communicated with the control oil passage of the first port B proportional valve interface 253; load feedback chambers 142 are all in communication with the load feedback channel; the pressure cavities 143 are communicated with the oil inlets P; the working chamber 144 of the first control valve cavity 101 is communicated with a first working oil port A, and the working chamber 144 of the second control valve cavity 102 is communicated with a second working oil port B; the oil return cavities 145 are all communicated with an oil return port T, the pilot control cavity 146 of the first control valve cavity 101 is communicated with the control oil passage of the second port a proportional valve interface 252, and the pilot control cavity 146 of the second control valve cavity 102 is communicated with the control oil passage of the second port B proportional valve interface 254. The port A main control valve core 211 and the port B main control valve core 231 are respectively provided with a Ls signal hole 203, a pressure cavity oil saving groove 202, a working cavity oil saving groove 201 and an oil return cavity throttling groove 205 which are communicated with the respective valve core cavities, the side wall of the valve core cavity is also provided with a guide rail groove 204 which extends axially, and one end of the guide rail groove 204 is connected with the Ls signal hole 203. The pressure compensation valve core 221 of the port A and the pressure compensation valve core 241 of the port B are respectively provided with an oil outlet throttling groove 301, an oil inlet hole 302, an oil through hole 303 and a positioning hole 304, the oil through hole 303 is a blind hole arranged on one side of the pressure compensation valve core, the oil outlet throttling groove 301 and the oil inlet hole 302 are communicated with the oil through hole 303, and the positioning hole 304 is a blind hole arranged on the outer side wall of the pressure compensation valve core. The port a primary control spool 211 is mounted within the first control valve cavity 101, and the port a pressure compensating spool 221 is mounted within the spool cavity of the port a primary control spool 211. The port a main control spool 211 is movable within the first control valve chamber 101 such that the port a main control spool 211 is located at a center position of the middle, a working position on the right, and a drain position on the left within the first control valve chamber 101. When the port a main control valve core 211 is in the middle position, the working chamber 144 is not communicated with the pressure chamber 143 and the oil return chamber 145, and the hydraulic oil at the first working port a is in the locked state. When the port a main control valve core 211 is in a working position, the pressure chamber oil saving groove 202 is communicated with the pressure chamber 143, the working chamber oil saving groove 201 is communicated with the working chamber 144, and the Ls signal hole 203 is communicated with the load feedback chamber 142. The hydraulic oil at the oil inlet P passes through the pressure chamber 143, and after the flow is regulated by the pressure chamber oil-saving groove 202, enters the oil through hole 303 through the oil inlet hole 302, and then enters the working chamber 144 through the oil outlet regulating notch jointly formed by the oil outlet throttling groove 301 and the working chamber oil-saving groove 201, and is conveyed to the first working oil port a to drive the hydraulic actuator to work. The port a pressure compensation spool 221 can move in the spool cavity of the port a main control spool 211 under the combined action of the pressure of the hydraulic oil and the elastic force of the port a pressure compensation spring 222, so that the flow area of the oil outlet regulation notch jointly formed by the oil outlet throttling groove 301 and the working cavity oil saving groove 201 is changed, and the pressure compensation is performed on the hydraulic oil entering the working cavity 144. Meanwhile, the A port pressure compensation valve core 221 moves leftwards under the pressure action of the hydraulic oil in the oil through hole 303, so that the oil through hole 303 is communicated with the Ls signal hole 203 and the guide rail groove 204, and the load pressure is applied to the left end of the A port pressure compensation valve core 221 through the channel, so that the pressure difference between the inlet and the outlet of the A port main control valve core 211 is constant (equal to the elastic force of the A port pressure compensation spring 222), and at the moment, the hydraulic oil entering the working cavity 144 is only related to the opening size of the pressure cavity throttling groove 202 and is unrelated to the load pressure. In addition, the hydraulic oil in the oil through hole 303 enters the load feedback cavity 142 through the oil inlet hole 302 and the Ls signal hole 203, and is transmitted to other hydraulic elements through a load feedback channel to perform load sensitive adjustment. When the port a main control valve core 211 is at the drainage position, the oil return cavity throttling groove 205 is simultaneously communicated with the working cavity 144 and the oil return cavity 145, and the hydraulic oil at the first working port a passes through the working cavity 144, enters the oil return cavity 145 after the flow of the hydraulic oil is regulated by the oil return cavity throttling groove 205, and is drained to the hydraulic oil tank through the oil return port T. The B port primary control spool 231 is mounted within the second control valve chamber 102, and the B port pressure compensating spool 241 is mounted within the spool chamber of the B port primary control spool 231. The B port main control spool 231 is movable within the second control valve chamber 102 such that the B port main control spool 231 is located at a middle position of the middle, a working position on the left side, and a drain position on the right side within the second control valve chamber 102. When the B port main control spool 231 is in the neutral position, the working chamber 144 is not communicated with the pressure chamber 143 and the oil return chamber 145, and the hydraulic oil at the second working port B is in the locked state. When the B port main control valve core 231 is at the working position, the pressure chamber oil saving groove 202 is communicated with the pressure chamber 143, the working chamber oil saving groove 201 is communicated with the working chamber 144, and the Ls signal hole 203 is communicated with the load feedback chamber 142. The hydraulic oil at the oil inlet P passes through the pressure chamber 143, and after the flow is regulated by the pressure chamber oil-saving groove 202, enters the oil through hole 303 through the oil inlet hole 302, and then enters the working chamber 144 through the oil outlet regulating notch formed by the oil outlet throttling groove 301 and the working chamber oil-saving groove 201, and is conveyed to the second working oil port B to drive the hydraulic actuator to work. The B port pressure compensation spool 241 can move in the spool cavity of the B port main control spool 231 under the combined action of the pressure of the hydraulic oil and the elastic force of the B port pressure compensation spring 242, so that the flow area of an oil outlet regulation notch jointly formed by the oil outlet throttling groove 301 and the working cavity oil saving groove 201 is changed, and the pressure compensation is performed on the hydraulic oil entering the working cavity 144. Meanwhile, the pressure compensation valve core 241 of the port B moves rightwards under the pressure action of the hydraulic oil in the oil through hole 303, so that the oil through hole 303 is communicated with the Ls signal hole 203 and the guide rail groove 204, and the load pressure is applied to the right end of the pressure compensation valve core 241 of the port B through the channel, so that the pressure difference between the inlet and the outlet of the main control valve core 231 of the port B is constant (equal to the elastic force of the pressure compensation spring 242 of the port B), and at the moment, the hydraulic oil entering the working cavity 144 is only related to the opening size of the throttling groove 202 of the pressure cavity and is unrelated to the load pressure. In addition, the hydraulic oil in the oil through hole 303 enters the load feedback cavity 142 through the oil inlet hole 302 and the Ls signal hole 203, and is transmitted to other hydraulic elements through a load feedback channel to perform load sensitive adjustment. When the B port main control valve core 231 is at the drainage position, the oil return cavity throttling groove 205 is simultaneously communicated with the working cavity 144 and the oil return cavity 145, and the hydraulic oil at the second working port B passes through the working cavity 144, enters the oil return cavity 145 after the flow rate of the hydraulic oil is adjusted by the oil return cavity throttling groove 205, and is drained to the hydraulic oil tank through the oil return port T.

In some embodiments of the load port independent control load sensitive multiplex valve of the present invention, as shown in fig. 1 and 2, the valve body comprises a main valve body 11, a first end cap 12 and a second end cap 13. The first end cap 12 may be mounted to the left side of the main valve body 11 by screws, and the second end cap 13 may be mounted to the right side of the main valve body 11 by screws. The main body portions of the first and second

control valve chambers

101, 102 are disposed within the main valve body 11 symmetrically on either side of the main valve body 11, with one end of the first control valve chamber 101, typically the spring chamber 141, being disposed within the first end cap 12 and one end of the second control valve chamber 102, also typically the spring chamber 141, being disposed within the second end cap 13. The first end cap 12 is further provided with a first port a proportional valve port 251 and a second port a proportional valve port 252, and the second end cap 13 is further provided with a first port B proportional valve port 253 and a second port B proportional valve port 254. Sealing rings are arranged on the periphery of the connecting part of the passage and the cavity between the main valve body 11 and the first end cover 12 and the second end cover 13 so as to keep the connecting part of the passage and the cavity sealed.

In some embodiments of the load-port independent control load-sensitive multi-way valve of the present invention, as shown in fig. 1 and fig. 2, a port a secondary relief valve interface 26 and a port B secondary relief valve interface 27 are further provided on the valve body, generally the main valve body 11. The port A secondary overflow valve interface 26 is arranged between the first working oil port A and the oil return port T, the port A secondary overflow valve 41 can be installed on the port A secondary overflow valve interface 26, the port A secondary overflow valve 41 has set overflow pressure, when the pressure of the first working oil port A reaches the set overflow pressure, the port A secondary overflow valve 41 is opened, the first working oil port A is subjected to flow discharge, the upper pressure limit of the first working oil port A is controlled, and the safe work of the hydraulic actuating mechanism is guaranteed. The port B secondary overflow valve interface 27 is arranged between the second working oil port B and the oil return port T, the port B secondary overflow valve 42 can be installed on the port B secondary overflow valve interface 27, the port B secondary overflow valve 42 has set overflow pressure, when the pressure of the second working oil port B reaches the set overflow pressure, the port B secondary overflow valve 42 is opened, the second working oil port B is subjected to flow discharge, the upper pressure limit of the second working oil port B is controlled, and the safe work of the hydraulic actuating mechanism is guaranteed.

In some embodiments of the load port independent control load sensitive multi-way valve of the present invention, as shown in fig. 2, a load feedback port Ls is further disposed on the valve body, usually the main valve body 11. The first control valve cavity 101 and the second control valve cavity 102 are both provided with a load feedback cavity 142, and the load feedback oil port Ls is respectively communicated with the load feedback cavities 142 in the first control valve cavity 101 and the second control valve cavity 102. Load feedback pressure signals formed by the A port pressure compensation valve structure 22 and the B port main control valve structure 23 can be transmitted to the ports of three-way pressure compensation valves of other work couplings and oil inlet couplings or the LS ports of variable pumps of hydraulic systems through the load feedback oil ports Ls, the opening degree of valve ports of related hydraulic components or the swing angle of the variable pumps is controlled, and therefore the oil supply flow and pressure of the hydraulic systems are adjusted, and the load sensing function of the hydraulic systems is achieved.

The working principle of the load port independent control load sensitive multi-way valve of the present invention will be described below by taking as an example the preferred embodiment as shown in the attached drawings:

when the first port a proportional pressure reducing valve 31 is powered on, hydraulic oil at the oil inlet P enters the first port a proportional valve interface 251 through the oil inlet duct 281, and after the pressure of the first port a proportional pressure reducing valve 31 is reduced, the hydraulic oil enters the spring cavity 141 of the first control valve cavity 101 through the control oil duct, so that the port a main control valve spool 211 is pushed to move to the right side in the first control valve cavity 101, and the port a main control valve spool 211 is located at a working position. The pressure chamber oil-saving groove 202 and the working chamber oil-saving groove 201 of the a-port main control spool 211 communicate with the pressure chamber 145 and the working chamber 144 of the first control valve chamber 101, respectively. At this time, the hydraulic oil from the oil inlet P passes through the pressure chamber throttling groove 202, enters the oil through hole 303 through the oil inlet hole 302 of the port a pressure compensating valve core 221, acts on the right side of the port a pressure compensating valve core 221, and pushes the port a pressure compensating valve core 221 to move leftward. The hydraulic oil enters the working chamber 144 of the first control valve chamber 101 after passing through the oil outlet throttling groove 301 and the working chamber oil saving groove 201, and drives the hydraulic execution structure connected to the first working oil port a to act. Meanwhile, the hydraulic oil enters the port a secondary overflow valve interface 26 and acts on the port a secondary overflow valve 41, when the pressure of the first working oil port a reaches the overflow pressure set by the port a secondary overflow valve 41, the port a secondary overflow valve 41 is opened, and the hydraulic oil is drained back to the oil return port T through the port a secondary overflow valve 41. Meanwhile, as the port a pressure compensation valve core 221 moves leftwards, the oil through hole 303 is communicated with the LS signal hole 203 and the guide rail groove 204 on the port a main control valve core 211, and the load pressure acts on the left end of the port a pressure compensation valve core 221 through the channel, so that the displacement of the port a pressure compensation valve core 221 is only affected by the elastic force of the port a pressure compensation spring 222, and the pressure difference between the inlet and the outlet of the port a main control valve core 211 is ensured to be constant. At this time, the flow rate of the hydraulic oil entering the first working port a is related only to the opening size of the pressure chamber oil-saving groove 202, and is not related to the load pressure. Meanwhile, the load pressure is also transmitted to other hydraulic components through the load feedback cavity 142 and the load feedback channel of the first control valve cavity 101 through the LS signal hole 203, so that the load sensing function is realized. When the first port a proportional pressure reducing valve 31 is de-energized or is in the neutral position, the hydraulic oil in the spring cavity 141 of the first control valve cavity 101 is drained back to the oil return port T through the control oil passage of the first port a proportional valve interface 251, the first port a proportional valve interface 251 and the oil return oil passage 282, the port a main control valve core 211 returns to the neutral position, and the oil inlet P is not communicated with the first working oil port a.

When the second port-a proportional pressure reducing valve 32 is powered on, hydraulic oil at the oil inlet P enters the second port-a proportional valve interface 252 through the oil inlet duct 281, is reduced in pressure through the second port-a proportional pressure reducing valve 32, enters the pilot control cavity 146 of the first control valve cavity 101 through the control oil duct, and pushes the port-a main control valve core 211 to move to the left, so that the oil return cavity throttling groove 205 of the port-a main control valve core 211 is simultaneously communicated with the working cavity 144 and the oil return cavity 145 of the first control valve cavity 101, and hydraulic oil at the first working oil port a flows back to the oil return port T through the working cavity 144 of the first control valve cavity 101, the oil return cavity throttling groove 205, and the oil return cavity 145 of the first control valve cavity 101. When the second port-a proportional pressure reducing valve 32 is de-energized or is in the neutral position, the hydraulic oil in the pilot control chamber 146 of the first control valve chamber 101 is drained back to the oil return port T through the control oil passage of the second port-a proportional valve interface 252, the second port-a proportional valve interface 252 and the oil return oil passage 282, and the oil inlet P is not communicated with the first working oil port a.

Similarly, when the first port B proportional pressure reducing valve 33 is powered on, the hydraulic oil at the oil inlet P enters the first port B proportional valve interface 253 through the oil inlet duct 281, and after being reduced in pressure by the first port B proportional pressure reducing valve 33, enters the spring cavity 141 of the second control valve cavity 102 through the control oil duct thereof, so as to push the port B main control valve spool 231 to move to the left side in the second control valve cavity 102, and the port B main control valve spool 231 is located at the working position. The pressure chamber oil-saving groove 202 and the working chamber oil-saving groove 201 of the B-port main control spool 231 communicate with the pressure chamber 145 and the working chamber 144 of the second control valve chamber 102, respectively. At this time, the hydraulic oil from the oil inlet P passes through the pressure chamber throttling groove 202, enters the oil through hole 303 through the oil inlet hole 302 of the B port pressure compensation valve core 241, acts on the left side of the B port pressure compensation valve core 241, and pushes the B port pressure compensation valve core 241 to move to the right. The hydraulic oil enters the working chamber 144 of the second control valve chamber 102 after passing through the oil outlet throttling groove 301 and the working chamber oil saving groove 201, and drives the hydraulic execution structure connected to the second working oil port B to act. Meanwhile, the hydraulic oil enters the port B secondary overflow valve interface 27 and acts on the port B secondary overflow valve 42, when the pressure of the second working oil port B reaches the overflow pressure set by the port B secondary overflow valve 42, the port B secondary overflow valve 42 is opened, and the hydraulic oil is drained back to the oil return port T through the port B secondary overflow valve 42. Meanwhile, as the B port pressure compensation valve core 241 moves rightwards, the oil through hole 303 is communicated with the LS signal hole 203 and the guide rail groove 204 on the B port main control valve core 231, and the load pressure acts on the right end of the B port pressure compensation valve core 241 through the channel, so that the displacement of the B port pressure compensation valve core 241 is only influenced by the elastic force of the B port pressure compensation spring 242, and the constant pressure difference between the inlet and the outlet of the B port main control valve core 231 is ensured. At this time, the flow rate of the hydraulic oil entering the second working port B is related only to the opening size of the pressure chamber oil-saving groove 202, and is not related to the load pressure. Meanwhile, the load pressure is also transmitted to other hydraulic components through the load feedback cavity 142 and the load feedback channel of the second control valve cavity 102 through the LS signal hole 203, so that the load sensing function is realized. When the first B port proportional pressure reducing valve 33 is de-energized or is in the neutral position, the hydraulic oil in the spring cavity 141 of the second control valve cavity 102 is drained back to the oil return port T through the control oil passage of the first B port proportional valve interface 253, the first B port proportional valve interface 253 and the oil return oil passage 282, the B port main control valve core 231 returns to the neutral position, and the oil inlet P is not communicated with the second working oil port B.

When the second B port proportional pressure reducing valve 34 is powered on, the hydraulic oil at the oil inlet P enters the second B port proportional valve interface 254 through the oil inlet passage 281, after the pressure of the second B port proportional pressure reducing valve 34 is reduced, the hydraulic oil enters the pilot control cavity 146 of the second control valve cavity 102 through the control oil passage, the B port main control valve spool 231 is pushed to move to the right side, the oil return cavity throttling groove 205 of the B port main control valve spool 231 is simultaneously communicated with the working cavity 144 and the oil return cavity 145 of the second control valve cavity 102, and the hydraulic oil at the second working oil port B flows back to the oil return port T through the working cavity 144, the oil return cavity throttling groove 205 of the second control valve cavity 102 and the oil return cavity 145 of the second control valve cavity 102. When the second B-port proportional pressure reducing valve 34 is de-energized or in the neutral position, the hydraulic oil in the pilot control chamber 146 of the second control valve chamber 102 is drained back to the oil return port T through the control oil passage of the second B-port proportional valve interface 254, the second B-port proportional valve interface 254 and the oil return oil passage 282, and the oil inlet P is not communicated with the second working oil port B.

Therefore, independent control of oil supply to the first working oil port a and the second working oil port B can be realized by controlling the operation of the first a-port proportional pressure reducing valve 31 or the first B-port proportional pressure reducing valve 33. By controlling the operation of the second port a proportional pressure reducing valve 32 or the second port B proportional pressure reducing valve 34, the independent control of the oil return of the first working port a and the second working port B can be realized. Therefore, when the first working oil port A (or the second working oil port B) is independently connected with the single-acting oil cylinder, the single-acting oil cylinder can extend out by controlling the first A port proportional pressure reducing valve 31 (or the first B port proportional pressure reducing valve 33) to be electrically operated; and controlling the second A-port proportional pressure reducing valve 32 (or the second B-port proportional pressure reducing valve 34) to work electrically to reset the single-acting oil cylinder. When the first working oil port A and the second working oil port B are simultaneously connected with the double-acting oil cylinder or the hydraulic motor, the functions of extending and contracting the hydraulic oil cylinder or forward and backward rotation of the hydraulic motor and the like can be realized by respectively controlling the working sequence of each proportional pressure reducing valve.

An embodiment of the hydraulic system of the present invention, using the load port independent control load sensitive multi-way valve of any embodiment of the present invention, also has the advantages of the corresponding embodiment of the load port independent control load sensitive multi-way valve of the present invention.

In the description of the present invention, reference to the description of the terms "one embodiment," "some embodiments," "a specific embodiment," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In the present disclosure, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, numerous simple modifications can be made to the technical solution of the invention, including combinations of the individual specific technical features in any suitable way. The invention is not described in detail in order to avoid unnecessary repetition. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.

Claims

1. A load port independent control load sensitive multi-way valve comprises a valve body and a valve structure arranged on the valve body, and is characterized in that an oil inlet (P), an oil return port (T), a first working oil port (A) and a second working oil port (B) which are connected with each other are arranged on the valve body, a first control valve cavity (101) and a second control valve cavity (102) are arranged in the valve body, an A port main control valve structure (21) and an A port pressure compensation valve structure (22) are arranged in the first control valve cavity (101) so as to control hydraulic oil of the oil inlet (P) to be delivered to the first working oil port (A) after pressure compensation, or hydraulic oil of the first working oil port (A) is unloaded through the oil return port (T) and can control the A port pressure compensation valve structure (22) to perform pressure compensation according to the pressure of the first working oil port (A), a B port main control valve structure (23) and a B port pressure compensation valve structure (24) are arranged in the second control valve cavity (102) to control hydraulic oil of the oil inlet (P) to be conveyed to the second working oil port (B) after pressure compensation, or hydraulic oil of the second working oil port (B) passes through the oil return port (T) for unloading, and pressure compensation can be carried out on the B port pressure compensation valve structure (24) according to pressure control of the second working oil port (B).

2. The load port independent control load-sensitive multi-way valve according to claim 1, wherein the valve body is further provided with a first A port proportional valve interface (251), a second A port proportional valve interface (252), a first B port proportional valve interface (253) and a second B port proportional valve interface (254), a first A port proportional pressure reducing valve (31) can be installed through the first A port proportional valve interface (251) so as to convert the hydraulic oil of the oil inlet (P) into pilot control hydraulic oil to be delivered to one side control end of the A port main control valve structure (21), a second A port proportional pressure reducing valve (32) can be installed through the second A port proportional valve interface (252) so as to convert the hydraulic oil of the oil inlet (P) into pilot control hydraulic oil to be delivered to the other side control end of the A port main control valve structure (21), through first B mouthful proportional valve interface (253) can install first B mouthful proportional reducing valve (33), with can with the hydraulic oil of oil inlet (P) converts the pilot control hydraulic oil into and carries one side control end of B mouthful main control valve structure (23), through second B mouthful proportional valve interface (254) can install second B mouthful proportional reducing valve (34), with can with the hydraulic oil of oil inlet (P) converts the pilot control hydraulic oil into and carries the opposite side control end of B mouthful main control valve structure (23).

3. The load port independent control load sensitive multi-way valve according to claim 2, wherein the first port a proportional valve interface (251), the second port a proportional valve interface (252), the first port B proportional valve interface (253) and the second port B proportional valve interface (254) each comprise an oil inlet passage (281), an oil return passage (282) and a control oil passage, the oil inlet passage (281) is communicated with the oil inlet (P), the oil return passage (282) is communicated with the oil return port (T), and the control oil passages are respectively communicated with control ends at two sides of the port a main control valve structure (21) and the port B main control valve structure (23).

4. The load port independent control load sensitive multiplex valve as defined in claim 2, wherein said port a pressure compensating valve structure (22) is disposed inside said port a main control valve structure (21); the port B pressure compensation valve structure (24) is arranged inside the port B main control valve structure (23).

5. The load port independent control load sensitive multi-way valve according to claim 4, wherein the port A main control valve structure (21) comprises a port A main control valve core (211), a port A connection spring seat (212), a port A reset spring seat (213) and a port A reset spring (214), a valve core cavity with an open end is arranged in the port A main control valve core (211), the port A connection spring seat (212) is connected with the end of the valve core cavity opening of the port A main control valve core (211), the port A reset spring seat (213) is sleeved on the port A main control valve core (211), the port A reset spring (214) is arranged between the port A reset spring seat (213) and the port A connection spring seat (212), and the port A pressure compensation valve structure (22) is arranged in the valve core cavity of the port A main control valve core (211), one end, where the A port connecting spring seat (212) is located, of the first control valve cavity (101) is communicated with the first A port proportional valve interface (251), and the other end of the first control valve cavity is communicated with the second A port proportional valve interface (252); the port B main control valve structure (23) comprises a port B main control valve core (231), a port B connecting spring seat (232), a port B reset spring seat (233) and a port B reset spring (234), a valve core cavity with an opening at one end is arranged in the port B main control valve core (231), the port B connecting spring seat (232) is connected with the end of the opening of the valve core cavity of the port B main control valve core (231), the port B reset spring seat (233) is sleeved on the port B main control valve core (231), the port B reset spring (234) is arranged between the port B reset spring seat (233) and the port B connecting spring seat (232), the port B pressure compensation valve structure (24) is arranged in the valve core cavity of the port B main control valve core (231), one end of the port B connecting spring seat (232) of the second control valve cavity (102) is communicated with the first port B proportional valve interface (253), the other end is communicated with the second port B proportional valve interface (254).

6. The load port independent control load sensitive multi-way valve according to claim 5, wherein the port A pressure compensating valve structure (22) comprises a port A pressure compensating valve core (221) and a port A pressure compensating spring (222), the port A pressure compensating valve core (221) is arranged in a valve core cavity of the port A main control valve core (211), the port A pressure compensating spring (222) is arranged between the port A pressure compensating valve core (221) and the port A connecting spring seat (212), and the port A pressure compensating valve core (221) can move in the valve core cavity of the port A main control valve core (211); the port B pressure compensation valve structure (24) comprises a port B pressure compensation valve core (241) and a port B pressure compensation spring (242), the port B pressure compensation valve core (241) is arranged in a valve core cavity of the port B main control valve core (231), the port B pressure compensation spring (242) is arranged between the port B pressure compensation valve core (241) and the port B connecting spring seat (232), and the port B pressure compensation valve core (241) can move in the valve core cavity of the port B main control valve core (231).

7. The load port independent control load-sensitive multi-way valve according to claim 6, wherein the first control valve cavity (101) and the second control valve cavity (102) each comprise a spring cavity (141), a load feedback cavity (142), a pressure cavity (143), a working cavity (144), a return oil cavity (145) and a pilot control cavity (146), the spring cavity (141) is communicated with the first port A proportional valve interface (251) or the first port B proportional valve interface (253), the load feedback cavity (142) is communicated with a load feedback channel, the pressure cavity (143) is communicated with the oil inlet (P), the working cavity (144) is communicated with the first working oil port (A) or the second working oil port (B), the return oil cavity (145) is communicated with the return oil port (T), and the pilot control cavity (146) is communicated with the second port A proportional valve interface (252) or the second port B proportional valve interface (254), the port A main control valve core (211) and the port B main control valve core (231) are respectively provided with a guide rail groove (204), a Ls signal hole (203), a pressure cavity oil saving groove (202), a working cavity oil saving groove (201) and an oil return cavity throttling groove (205) which are communicated with respective valve core cavities, the guide rail groove (204) is connected with the Ls signal hole (203), the port A pressure compensation valve core (221) and the port B pressure compensation valve core (241) are respectively provided with an oil outlet throttling groove (301), an oil inlet hole (302) and an oil through hole (303), and the oil outlet throttling groove (301) and the oil inlet hole (302) are respectively communicated with the oil through hole (303) arranged on one side of the valve core; the A port main control valve core (211) and the B port main control valve core (231) can respectively move in the first control valve cavity (101) and the second control valve cavity (102), when the port A main control valve core (211) or the port B main control valve core (231) is in a neutral position, the pressure cavity (143) is not communicated with the working cavity (144), when the A port main control valve core (211) or the B port main control valve core (231) is in a working position, the Ls signal aperture (203) communicates with the load feedback chamber (142), the pressure cavity oil-saving groove (202) is communicated with the pressure cavity (143), the working cavity oil-saving groove (201) is communicated with the working cavity (144), when the port A main control valve core (211) or the port B main control valve core (231) is in a drainage position, the oil return cavity throttling groove (205) is communicated with the working cavity (144) and the oil return cavity (145) simultaneously; a mouthful pressure compensation case (221) and B mouthful pressure compensation case (241) are installed respectively the case intracavity of A mouthful main control case (211) and B mouthful main control case (231), make inlet port (302) can with Ls signal hole (203) and pressure chamber oil-saving groove (202) are linked together, oil outlet throttle groove (301) with working chamber oil-saving groove (201) are linked together, A mouthful pressure compensation case (221) and B mouthful pressure compensation case (241) can be in respectively the case intracavity of A mouthful main control case (211) and B mouthful main control case (231) removes in order to can adjust export throttle groove (301) with the through flow area between working chamber oil-saving groove (201).

8. The load port independent control load sensitive multiplex valve of any one of claims 1-7, characterized in that the valve body comprises a main valve body (11), a first end cover (12) and a second end cover (13), the first end cover (12) and the second end cover (13) are respectively arranged at two sides of the main valve body (11), the main body parts of the first control valve chamber (101) and the second control valve chamber (102) are positioned in the main valve body (11), one end of the first control valve cavity (101) is positioned in the first end cover (12), one end of the second control valve cavity (102) is positioned in the second end cover (13), the first end cover (12) is provided with a first A port proportional valve interface (251) and a second A port proportional valve interface (252), and a first port B proportional valve interface (253) and a second port B proportional valve interface (254) are arranged on the second end cover (13).

9. The load port independent control load sensitive multi-way valve according to any one of claims 1-7, wherein the valve body is further provided with an A port secondary overflow valve interface (26) and a B port secondary overflow valve interface (27), the A port secondary overflow valve interface (26) is arranged between the first working oil port (A) and the oil return port (T), and an A port secondary overflow valve (41) can be installed through the A port secondary overflow valve interface (26) so as to discharge the first working oil port (A) when the pressure of the first working oil port (A) reaches a set pressure; the port B secondary overflow valve interface (27) is arranged between the second working oil port (B) and the oil return port (T), and a port B secondary overflow valve (42) can be installed through the port B secondary overflow valve interface (27) so that the second working oil port (B) can be subjected to flow discharge when the pressure of the second working oil port (B) reaches a set pressure.

10. The load port independent control load sensing multi-way valve according to any one of claims 1-7, wherein a load feedback port (Ls) is further provided on the valve body, and the first control valve chamber (101) and the second control valve chamber (102) each comprise a load feedback chamber (142), and the load feedback port (Ls) is communicated with the load feedback chambers (142) in the first control valve chamber (101) and the second control valve chamber (102).

11. A hydraulic system comprising a load port independently controlled load sensitive multiplex valve according to any of claims 1-10.