CN218062869U

CN218062869U - Multi-way valve and hydraulic system

Info

Publication number: CN218062869U
Application number: CN202221206695.5U
Authority: CN
Inventors: 董立队; 迟峰; 王永; 常鸿; 朱博; 王世东; 牛肇; 时少雷; 厉兆虎; 赵团国; 张晓朵; 罗明
Original assignee: Shandong Lingong Construction Machinery Co Ltd
Current assignee: Shandong Lingong Construction Machinery Co Ltd
Priority date: 2022-05-18
Filing date: 2022-05-18
Publication date: 2022-12-16
Anticipated expiration: 2032-05-18

Abstract

The utility model discloses a multiple unit valve and hydraulic system relates to hydraulic pressure technical field. The multi-way valve comprises a valve body, a change-over valve and a working valve group, wherein the change-over valve is provided with a change-over valve rod, a first cavity and a second cavity; if the pressure difference between the working valve oil inlet and the working cavity is smaller than or equal to a first preset value, the switching valve rod is located at a first position, so that an oil path between the first oil inlet and the working valve oil inlet is conducted; if the pressure difference between the working valve oil inlet and the working cavity is larger than the first preset value, the switching valve rod is located at the second position, so that the oil path between the first oil inlet and the working valve oil inlet is cut off, confluence or pressure relief is realized, and the purpose of energy conservation is achieved.

Description

Multi-way valve and hydraulic system

Technical Field

The utility model relates to a hydraulic pressure technical field particularly, relates to a multiple unit valve and hydraulic system.

Background

The operation working conditions of the loader mainly comprise shoveling operation and loading operation, in order to realize efficient operation, the whole loader needs to be frequently steered left and right, the execution module needs to be frequently subjected to bucket retracting, lifting, unloading, descending and the like, and the actions are controlled and realized through a hydraulic system of the loader.

The loader hydraulic system generally includes an implement module hydraulic system and a steering hydraulic system. In the prior art, if two pumps (such as a working pump and a steering pump) are adopted to independently control an execution module and a steering device, the efficiency of a hydraulic system is low, and better matching of flow cannot be realized during compound action. If the execution module hydraulic system and the steering hydraulic system adopt a hybrid system, namely when the steering hydraulic system does not work, the steering hydraulic system is shunted by the shunt valve device and is converged with the working pump to supply oil to the multi-way valve of the loader; the flow combining can be realized, the flow distribution can be optimized to a certain degree, but the structure is complex, the hydraulic system is complex, and the cost is high.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a multiple unit valve and hydraulic system, for example, it can realize confluence, the off-load of steering pump and working pump, and hydraulic system is energy-conserving efficient good, and the structure is simple relatively, reduce cost.

The embodiment of the utility model discloses a can realize like this:

in a first aspect, the utility model provides a multi-way valve, which comprises a valve body, and a change-over valve and a working valve group which are arranged on the valve body, wherein a first oil inlet P and a second oil inlet EF are arranged on the valve body, the first oil inlet P is used for being communicated with a working pump, and the second oil inlet EF is used for being communicated with a steering pump;

the changeover valve is provided with a changeover valve rod, a first chamber and a second chamber, and the changeover valve rod can move in the first chamber and the second chamber; the working valve group is provided with a working valve oil inlet which is communicated with the first cavity, the valve body is provided with a load sensing oil duct ls, and the load sensing oil duct ls is communicated with the second cavity; if the pressure difference between the working valve oil inlet and the first cavity is smaller than or equal to a first preset value, the conversion valve rod is located at a first position, so that an oil path between the first oil inlet P and the working valve oil inlet is communicated; and if the pressure difference between the working valve oil inlet and the first cavity is greater than the first preset value, the conversion valve rod is located at a second position, so that an oil path between the first oil inlet P and the working valve oil inlet is cut off.

In an optional embodiment, the valve body is provided with an oil return port T, a pilot oil inlet and a load sensing oil port LS, the pilot oil inlet is used for being communicated with a pilot valve, and the oil return port T and the load sensing oil port LS are respectively communicated with an oil tank;

the working valve group is provided with a control cavity, a working cavity and a working valve rod, wherein a working valve oil inlet is respectively communicated with a first oil inlet P and a second oil inlet EF, a pilot oil inlet is communicated with the control cavity, pilot oil enters the control cavity from the pilot oil inlet, the pilot oil is used for driving the working valve rod to move, so that the working valve oil inlet is communicated with the working cavity, and the working cavity is used for being connected with an execution module.

In an alternative embodiment, the load sensing oil passage LS is communicated with the load sensing oil port LS, and the load sensing oil port is used for being connected with a compensator of the steering pump, so that the displacement of the steering pump can be adjusted.

In an optional implementation manner, a shuttle valve is arranged on the valve body, an oil inlet of the shuttle valve is communicated with the regulating oil passage, and an oil outlet of the shuttle valve is communicated with the load sensing oil passage ls.

In an alternative embodiment, the oil inlet of the switching valve is communicated with the first oil inlet P, and the oil outlet of the switching valve is communicated with the working valve group; the switching valve rod is provided with a first oil duct rsi and a second oil duct rst, an oil inlet of the switching valve is communicated with an oil outlet of the switching valve through the first oil duct rsi, and an oil inlet of the switching valve is communicated with an oil return port of the switching valve through the second oil duct rst.

In an alternative embodiment, one end of the switching valve rod is provided with a first elastic piece, and the first elastic piece is arranged in the second chamber; if the pressure difference between the first chamber and the second chamber is smaller than or equal to the elastic force of the first elastic piece, the switching valve rod is located at a first position, so that the oil inlet of the switching valve is communicated with the oil outlet of the switching valve through the first oil passage rsi; if the pressure difference between the first chamber and the second chamber is larger than the elastic force of the first elastic piece, the switching valve rod moves to a second position, so that the oil inlet of the switching valve is communicated with the oil return port of the switching valve through the second oil passage rst.

In an alternative embodiment, the control chamber is provided with a second elastic member connected to the working stem to place the working stem in a third position or a fourth position;

the working valve rod is provided with a first channel, a second channel, a third channel and a fourth channel, the working valve group is provided with a first working cavity and a second working cavity, and the first working cavity and the second working cavity are respectively connected with the execution module;

the working valve rod is located at the third position, an oil inlet of the working valve group is communicated with the first working cavity through the first channel, and the second working cavity is communicated with the oil return port through the fourth channel;

the working valve rod is located at the fourth position, an oil inlet of the working valve group is communicated with the second working cavity through the third channel, and the first working cavity is communicated with the oil return port through the second channel.

In an optional embodiment, an adjusting oil duct is arranged on the working valve rod, the adjusting oil duct includes a first damping hole, a second damping hole and an internal oil duct, the first damping hole is communicated with the first working cavity, the second damping hole is communicated with the second working cavity, the first damping hole and the second damping hole are respectively communicated with the internal oil duct, and the internal oil duct is communicated with the load sensing oil port.

In an optional embodiment, the work valve group includes a boom control valve and a bucket control valve, the first oil inlet P is connected to the boom control valve and the bucket control valve through the change-over valve, respectively, and the second oil inlet EF is connected to the boom control valve and the bucket control valve, respectively; the working valve rod comprises a movable arm valve rod and a rotary hopper valve rod, the movable arm valve rod is movably arranged on the movable arm control valve, and the rotary hopper valve rod is movably arranged on the rotary hopper control valve;

the pilot oil inlet comprises a first pilot oil inlet, a second pilot oil inlet, a third pilot oil inlet and a fourth pilot oil inlet, one end of the movable arm valve rod is communicated with the first pilot oil inlet, and the other end of the movable arm valve rod is communicated with the second pilot oil inlet; one end of the rotating bucket valve rod is communicated with the third pilot oil inlet, and the other end of the rotating bucket valve rod is communicated with the fourth pilot oil inlet.

In an alternative embodiment, the second elastic member includes a second spring and a third spring, the second spring is disposed at one end of the swing arm valve rod, and the third spring is disposed at one end of the swing arm valve rod.

In an optional embodiment, the valve body is provided with a first oil return passage T0 and a second oil return passage T1; a back pressure valve is arranged on the valve body, and the second oil return channel T1 is communicated with the first oil return channel T0 through the back pressure valve;

in the movable arm control valve, the first working cavity comprises a movable arm ascending cavity which is used for being connected with a large cavity of a movable arm oil cylinder; the second working cavity comprises a movable arm descending cavity and is used for being connected with a small cavity of the movable arm oil cylinder; the return oil of the movable arm ascending cavity is communicated with the second return oil duct T1, and the return oil of the movable arm descending cavity is communicated with the first return oil duct T0; the first oil return oil channel T0 is communicated with the oil return port T.

In an optional embodiment, in the bucket control valve, the first working chamber includes a bucket collecting chamber for connecting with a large chamber of a bucket cylinder; the second working cavity comprises a rotary hopper discharging cavity which is used for being connected with a small cavity of the rotary hopper oil cylinder; and the return oil of the rotating hopper receiving cavity is communicated with the second return oil duct T1, and the return oil of the rotating hopper discharging cavity is communicated with the first return oil duct T0.

In an optional embodiment, a shuttle valve is arranged on the valve body, the shuttle valve is provided with a first oil port, a second oil port and a third oil port, the first oil port is communicated with the adjusting oil duct on the movable arm valve rod, the second oil port is communicated with the adjusting oil duct on the rotating bucket valve rod, and the third oil port is communicated with the load sensing oil port.

In an optional embodiment, an overflow valve is arranged on the valve body, a high-pressure cavity of the overflow valve is communicated with the load sensing oil passage ls, and an oil return port of the overflow valve is communicated with the oil return port T.

In an alternative embodiment, the control system further comprises a pressure reducing valve disposed on the control oil path between the pilot oil inlet and the control chamber.

In a second aspect, the present invention provides a hydraulic system, comprising a working pump, a steering pump, an actuator module and a multi-way valve as in any one of the previous embodiments, wherein the working pump and the steering pump are respectively connected to the multi-way valve, and the multi-way valve is connected to the actuator module.

The utility model discloses beneficial effect includes, for example:

the multi-way valve can realize confluence of the working pump and the steering pump by arranging the switching valve rod, optimize flow distribution, improve working efficiency and achieve the aim of energy conservation. The load sensing oil duct is arranged on the working valve rod, oil in the load sensing oil duct enters the change-over valve, and the position of the change-over valve rod is changed to realize the opening or closing of the change-over valve, so that an oil path between the working pump and the working valve group is communicated or cut off, the working pump can be better matched with the flow of the steering pump when in confluence, the unloading of the working pump is realized, the energy-saving efficiency of a hydraulic system is good, the structure is simple and compact, and the cost is reduced.

The hydraulic system comprises the multi-way valve, the working pump and the steering pump are respectively connected with the multi-way valve, the multi-way valve is connected with the execution module, confluence and unloading of the working pump can be achieved, the hydraulic system is good in energy-saving efficiency, and cost reduction is facilitated.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic diagram of a hydraulic system according to an embodiment of the present invention;

FIG. 2 is an enlarged schematic illustration of the hydraulic control system of the multiplex valve of FIG. 1;

FIG. 3 is an enlarged schematic view of the hydraulic control system of the steering pump of FIG. 1;

fig. 4 is a schematic structural diagram of a first view angle of the multi-way valve according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a second view angle of the multi-way valve according to the embodiment of the present invention;

FIG. 6 isbase:Sub>A schematic cross-sectional view taken along line A-A in FIG. 5;

FIG. 7 is a schematic view of the structure of FIG. 4 from the E-direction;

fig. 8 is a schematic structural diagram of an oil return port T of the multi-way valve according to an embodiment of the present invention;

FIG. 9 is a schematic view of the structure of FIG. 8 from the perspective of G;

FIG. 10 is a schematic cross-sectional view of D-D in FIG. 4;

FIG. 11 is a schematic cross-sectional view taken along line C-C in FIG. 4;

fig. 12 is a schematic cross-sectional structure diagram of the connection between the second oil inlet EF and the oil passage EF in the present embodiment;

fig. 13 is a schematic cross-sectional view illustrating a structure of the working valve assembly connected to the load sensing oil passage ls through the shuttle valve in the present embodiment;

FIG. 14 is a schematic cross-sectional view of the back pressure valve of the present embodiment;

fig. 15 is a schematic cross-sectional view of the first check valve in this embodiment.

An icon: 100-a multi-way valve; 110-a valve body; 200-a switching valve; 201-switching valve rod; 203-a first spring; cs 1-a first chamber; c1 s-second chamber; 300-a working valve group; 301-boom cylinder; 303-rotating bucket oil cylinder; 310-boom control valve; 320-boom valve stem; 330-a second spring; 350-a bucket control valve; 360-rotating bucket valve rod; 370-a third spring; p-a first oil inlet; EF-a second oil inlet; t-oil return port; LS-load sensing oil port; ls-load sense gallery; rsi-first oil gallery; rst-second oil duct; t0-a first oil return duct; t1-a second oil return duct; xA 2-a first pilot oil inlet; xB 2-a second pilot oil inlet; xA 1-a third pilot oil inlet; xB 1-a fourth pilot oil inlet; 410-back pressure valve; 420-a first one-way valve; 430-a second one-way valve; 440-a third one-way valve; bl — boom-up chamber; bd-boom lowering chamber; bkl-rotating hopper cavity; bkd-rotating hopper discharge chamber; 101-a working pump; 103-a steering pump; 104-a compensator; 105-a pilot valve; 106-priority valve; 107-oil tank; 109-system shuttle valve; 120-shuttle valve; 130-a float control valve; 140-floating oil replenishing valve; 141-oil supplement valve; 160-relief valve; 460-a pressure relief valve; 170-main relief valve; 401-diverter.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that, if the terms "upper", "lower", "inner", "outer", etc. indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the products of the present invention are used, the description is only for convenience of description and simplification, but the indication or suggestion that the indicated device or element must have a specific position, be constructed and operated in a specific orientation, and thus, should not be interpreted as a limitation of the present invention.

Furthermore, the appearances of the terms "first," "second," and the like, if any, are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

It should be noted that the features of the embodiments of the present invention may be combined with each other without conflict.

Referring to fig. 1 to 15, fig. 1 to 3 are schematic diagrams illustrating a control principle of a hydraulic system, and fig. 4 to 15 are schematic diagrams illustrating structures of the multi-way valve 100 from different viewing angles.

The embodiment provides a multiway valve 100, which comprises a valve body 110, and a change-over valve 200 and a working valve group 300 which are arranged on the valve body 110, wherein a first oil inlet P, a second oil inlet EF, an oil return port T, a pilot oil inlet and a load sensing oil port LS are arranged on the valve body 110, the first oil inlet P is used for being communicated with a working pump 101, the second oil inlet EF is used for being communicated with a steering pump 103, the pilot oil inlet is used for being communicated with a pilot valve 105, and the oil return port T and the load sensing oil port LS are respectively communicated with an oil tank 107; the switching valve 200 is provided with a switching valve rod 201, a first chamber cs1 and a second chamber c1s, and the switching valve rod 201 can move in the first chamber cs1 and the second chamber c1s to achieve the connection or disconnection of the oil path.

The working valve group 300 is provided with a control cavity, a working valve rod and a working valve oil inlet, wherein the working valve oil inlet is respectively communicated with a first oil inlet P and a second oil inlet EF; an adjusting oil passage is arranged on the working valve rod, a load sensing oil passage ls is arranged on the valve body 110, one end of the adjusting oil passage is communicated with the working cavity, and the other end of the adjusting oil passage is communicated with the second cavity c1s through the load sensing oil passage ls; if the pressure difference between the working valve oil inlet and the working cavity is smaller than or equal to a first preset value, the switching valve rod 201 is located at a first position, so that an oil path between the first oil inlet P and the working valve oil inlet is communicated; if the pressure difference between the oil inlet of the working valve and the working cavity is greater than the first preset value, the switching valve rod 201 is located at the second position, so that the oil path between the first oil inlet P and the oil inlet of the working valve is cut off. The multi-way valve 100 can realize the conduction and the cutoff of an oil path between the working pump 101 and the working valve group 300 under the action of the switching valve 200, namely, the confluence and the unloading of the working pump 101 are realized, and the energy-saving efficiency is high.

It should be noted that, since the working valve oil inlet is communicated with the first cavity cs1, the working cavity is communicated with the second cavity c1s, and the pressure difference between the working valve oil inlet and the working cavity, that is, the pressure difference between the first cavity cs1 and the second cavity c1s on the switching valve 200.

It can be understood that the second chamber c1s is provided with a first elastic member, for example, the first spring 203, the first elastic member contacts with the switching valve rod 201, during the operation, if the pressure difference between the oil inlet of the working valve and the second chamber c1s is small, the elastic force of the first elastic member cannot be overcome to drive the switching valve rod 201 to move, the switching valve 200 is kept in the open state, the oil of the working pump 101 reaches the working valve set 300 through the switching valve 200, and is merged with the hydraulic oil output by the steering pump 103, so as to satisfy the working pressure of the working chamber. In the working process, if the pressure difference between the oil inlet of the working pump and the second chamber c1s is large, the elastic force of the first elastic member is overcome to drive the switching valve rod 201 to move, the switching valve 200 is switched to the closed state, the oil path between the working pump 101 and the working valve set 300 is cut off by the switching valve 200, and the oil of the working pump 101 flows back to the oil tank 107 through the switching valve 200, so that the unloading purpose of the working pump 101 is achieved.

Optionally, the load sensing oil passage LS is communicated with a load sensing oil port LS, and the load sensing oil port LS is used for being connected with a compensator 104 of the steering pump 103, so that the displacement of the steering pump 103 can be adjusted. When the working valve group 300 is in a working state, pressure oil in a working chamber enters the load sensing oil passage ls through the regulating oil passage, one part of oil in the load sensing oil passage ls enters the change-over valve 200, and the other part of the oil reaches the compensator 104 of the steering pump 103, so that the displacement of the steering pump 103 is adjusted, and the flow requirement of the working chamber is met. It is easy to understand that if the working chamber needs to work at a high speed, the oil in the load sensing oil passage ls acts on the compensator 104, and the compensator 104 increases the displacement of the steering pump 103; if the working chamber needs to work at a low speed, oil in the load sensing oil passage ls acts on the compensator 104, and the compensator 104 reduces the displacement of the steering pump 103.

The multi-way valve 100 can realize confluence of the working pump 101 and the steering pump 103 or unloading of the working pump 101 according to the actual flow demand of the working valve group 300, can also automatically adjust the discharge capacity of the steering pump 103, realizes optimal matching of flow, and realizes energy conservation in the state of meeting the normal work of the working valve group 300.

Optionally, a shuttle valve 120 is disposed on the valve body 110, an oil inlet of the shuttle valve 120 is communicated with the regulating oil passage, and an oil outlet of the shuttle valve 120 is communicated with the load sensing oil passage ls. That is, the oil in the working chamber enters the shuttle valve 120 through the adjustment oil passage, and flows to the switching valve 200 and the compensator 104 of the steering pump 103 through the shuttle valve 120.

In this embodiment, an oil inlet of the change-over valve 200 is communicated with the first oil inlet P, and an oil outlet of the change-over valve 200 is communicated with the work valve group 300; the first oil duct rsi and the second oil duct rst are arranged on the switching valve rod 201, an oil inlet of the switching valve 200 is communicated with an oil outlet of the switching valve 200 through the first oil duct rsi, and an oil inlet of the switching valve 200 is communicated with an oil return port T of the switching valve 200 through the second oil duct rst. Optionally, one end of the conversion valve rod 201 is provided with a first elastic member, and the first elastic member is arranged in the second chamber c1s; if the pressure difference between the pressure in the first chamber cs1 and the pressure in the second chamber c1s is smaller than or equal to the elastic force of the first elastic member, the switching valve rod 201 is at the first position, so that the oil inlet of the switching valve 200 is communicated with the oil outlet of the switching valve 200 through the first oil passage rsi; if the pressure difference between the pressure in the first chamber cs1 and the pressure in the second chamber c1s is greater than the elastic force of the first elastic member, the switching valve rod 201 moves to the second position, so that the oil inlet of the switching valve 200 is communicated with the oil return port T of the switching valve 200 through the second oil passage rst.

The control chamber of the work valve group 300 is provided with a second elastic member, and the second elastic member is connected with the work valve rod so as to enable the work valve rod to be in a third position or a fourth position; the working valve rod is provided with a first channel, a second channel, a third channel and a fourth channel, the working valve group 300 is provided with a first working cavity and a second working cavity, and the first working cavity and the second working cavity are respectively connected with the execution module. It can be understood that the working valve rod is in the third position, the oil inlet of the working valve group 300 is communicated with the first working cavity through the first channel, and the second working cavity is communicated with the oil return port T through the fourth channel; the working valve rod is in the fourth position, the oil inlet of the working valve group 300 is communicated with the second working cavity through the third channel, and the first working cavity is communicated with the oil return port T through the second channel.

The adjusting oil duct comprises a first damping hole, a second damping hole and an internal oil duct, the first damping hole is communicated with the first working cavity, the second damping hole is communicated with the second working cavity, the first damping hole and the second damping hole are respectively communicated with the internal oil duct, and the internal oil duct is communicated with the load sensing oil port LS through the shuttle valve 120.

It is understood that the multi-way valve 100 can be applied to a loader to implement hydraulic control of a boom and a rotating bucket, that is, the number of control valves in the work valve group 300 includes two, and in other application scenarios, the number of control valves in the work valve group 300 may also be one, three, four or more, and is not limited herein. In the present embodiment, the example in which the work valve group 300 includes the boom control valve 310 and the bucket control valve 350 will be described.

With reference to fig. 4 to 9, the first oil inlet P is connected to the boom control valve 310 and the bucket control valve 350 through the switching valve 200, and the second oil inlet EF is connected to the boom control valve 310 and the bucket control valve 350; the working valve rod comprises a movable arm valve rod 320 and a rotary bucket valve rod 360, the movable arm valve rod 320 is movably arranged on the movable arm control valve 310, and the rotary bucket valve rod 360 is movably arranged on the rotary bucket control valve 350. The pilot oil inlet comprises a first pilot oil inlet xA2, a second pilot oil inlet xB2, a third pilot oil inlet xA1 and a fourth pilot oil inlet xB1, one end of the movable arm valve rod 320 is communicated with the first pilot oil inlet xA2, and the other end of the movable arm valve rod is communicated with the second pilot oil inlet xB 2; one end of the rotary hopper valve rod 360 is communicated with a third pilot oil inlet xA1, and the other end of the rotary hopper valve rod is communicated with a fourth pilot oil inlet xB 1. Optionally, the second elastic member includes a second spring 330 and a third spring 370, the second spring 330 moves one end of the arm valve rod 320, which is disposed at the right end in the view shown in fig. 6 in this embodiment, and the third spring 370 is disposed at one end of the rotating bucket valve rod 360, which is disposed at the right end in the view shown in fig. 6 in this embodiment.

With reference to fig. 6 and 14, the valve body 110 is provided with a first oil return passage T0 and a second oil return passage T1, and the first oil return passage T0 is located on the right side of the valve body 110 and is communicated with the oil return port T. The second oil return passage T1 is located on the left side of the valve body 110, a back pressure valve 410 is disposed on the valve body 110, and the second oil return passage T1 is communicated with the first oil return passage T0 through the back pressure valve 410.

It can be understood that the control chamber of the work valve group 300 includes a left chamber and a right chamber of the movable arm valve rod 320 and a left chamber and a right chamber of the rotating bucket valve rod 360, the left chamber and the right chamber of the movable arm valve rod 320 are respectively communicated with the first pilot oil inlet xA2 and the second pilot oil inlet xB2, and the left chamber and the right chamber of the rotating bucket valve rod 360 are respectively communicated with the third pilot oil inlet xA1 and the fourth pilot oil inlet xB 1.

In this embodiment, the valve body 110 is provided with a first check valve 420, a second check valve 430 and a third check valve 440, an inlet of the first check valve 420 is communicated with an oil outlet of the switching valve 200, and an outlet of the first check valve 420 is communicated with the work valve group 300. The valve body 110 is provided with an oil passage EF, an oil passage P1, an oil passage P2, an oil passage P3, and an oil passage P4, one end of the oil passage EF is communicated with the second oil inlet EF, and the other end is communicated with the oil passage P2, the oil passage P2 is respectively communicated with the oil passages P1, P3, and P4, the oil passage P1 is communicated with the change-over valve 200, the oil passage P3 is communicated with the boom control valve 310, and the oil passage P4 is communicated with the bucket control valve 350. Optionally, the first oil inlet P enters the oil passage P1 through the first oil passage rsi of the switching valve 200, the oil passage P1 enters the oil passage P2 through the first check valve 420, the oil passage P2 enters the oil passage P3 through the second check valve 430, and the oil passage P2 enters the oil passage P4 through the third check valve 440. The oil passage P3 and the oil passage P4 are respectively connected with an oil inlet of the working valve.

The left side of the conversion valve rod 201 is a first cavity cs1, and the first cavity cs1 is communicated with an oil passage P2 through an oil passage; the right side of the switching valve rod 201 is a second chamber c1s, which is communicated with the load sensing oil passage ls through an oil passage.

The valve body 110 is provided with an overflow valve 160, a high-pressure cavity rp of the overflow valve 160 is communicated with the load sensing oil passage ls, and an oil return port T of the overflow valve 160 is communicated with a first oil return oil passage T0. If the pressure of the load sensing oil passage ls is higher than the pressure set by the overflow valve 160, the hydraulic oil in the load sensing oil passage ls is released through the overflow valve 160, so that the oil pressure of the second chamber c1s is lower, the switching valve rod 201 moves to enable the switching valve 200 to be in a cut-off state, the working pump 101 is unloaded, the high-pressure small-flow operation of the movable arm cylinder is realized, and the energy saving of the hydraulic system is realized.

In the boom control valve 310, the first working chamber includes a boom raising chamber bl for connecting with the large chamber of the boom cylinder 301; the second working cavity comprises a movable arm descending cavity bd which is used for being connected with a small cavity of the movable arm oil cylinder 301; the movable arm valve rod 320 is provided with a first channel, a second channel, a third channel and a fourth channel, namely oil channels rb1, tb2, rbd and tb1, a movable arm ascending cavity bl is communicated with a large cavity oil port A2 of the movable arm oil cylinder 301, and a movable arm descending cavity bd is communicated with a small cavity oil port B2 of the movable arm oil cylinder 301.

In this embodiment, oil enters the right side of the movable arm valve rod 320 from the first pilot oil inlet xA2 to control the movable arm valve rod 320 to move left, the movable arm rising cavity bl of the movable arm control valve 310 is located at a working position, and oil of the steering pump 103 enters the movable arm control valve 310 through the second oil inlet EF and enters the large cavity of the movable arm oil cylinder 301 through the movable arm rising cavity bl to control the lifting of the movable arm. Specifically, the oil passage P3 is communicated with the movable arm ascending cavity bl through the oil passage rb1, and the movable arm descending cavity bd is communicated with the first oil return oil passage T0 through the oil passage tb2, so that the lifting of the loader arm cylinder is realized.

Oil enters the left side of the movable arm valve rod 320 from the second pilot oil inlet xB2 to control the movable arm valve rod 320 to move right, the movable arm descending cavity bd of the movable arm control valve 310 is located at a working position, the oil of the steering pump 103 enters the movable arm control valve 310 through the second oil inlet EF and enters the small cavity of the movable arm oil cylinder 301 through the movable arm descending cavity bd to control the movable arm to descend. Specifically, the oil passage P3 is communicated with the boom descending cavity bd through the oil passage rbd, and the boom ascending cavity bl is communicated with the second oil return oil passage T1 through the oil passage tb1, so that the boom cylinder of the loader descends.

Similarly, in the bucket control valve 350, the first working chamber includes a bucket retracting chamber bkl for connecting with the large chamber of the bucket cylinder 303; the second working cavity comprises a rotary hopper unloading cavity bkd and is used for being connected with a small cavity of the rotary hopper oil cylinder 303; the return oil of the rotary hopper receiving cavity bkl is communicated with the second oil return oil passage T1, and the return oil of the rotary hopper unloading cavity bkd is communicated with the first oil return oil passage T0.

The rotating bucket valve rod 360 is provided with a first channel, a second channel, a third channel and a fourth channel, namely oil channels rbk1, rbk, rbkd and tbk1, a rotating bucket collecting cavity bkl is communicated with a large cavity oil port A1 of the rotating bucket oil cylinder 303, and a rotating bucket discharging cavity bkd is communicated with a small cavity oil port B1 of the rotating bucket oil cylinder 303. In this embodiment, oil enters the right side of the rotating bucket valve rod 360 from the third pilot oil inlet xA1 to control the rotating bucket valve rod 360 to move left, the rotating bucket cavity bkl of the rotating bucket control valve 350 is in a working position, the oil of the steering pump 103 enters the oil passage P2 through the second oil inlet EF, enters the oil passage P4 through the third check valve 440, and enters the large cavity of the rotating bucket oil cylinder 303 through the rotating bucket cavity bkl of the rotating bucket control valve 350 to control the rotating bucket to receive the bucket. Specifically, the oil duct P4 is communicated with a rotating bucket collecting cavity bkl through an oil duct rbk, and a rotating bucket discharging cavity bkd is communicated with a first oil return oil duct T0 through an oil duct rbk, so that the rotating bucket collecting of the loader is realized.

Oil enters the left side of the rotating bucket valve rod 360 from the fourth pilot oil inlet xB1 to control the rotating bucket valve rod 360 to move right, the rotating bucket unloading cavity bkd of the rotating bucket control valve 350 is located at a working position, the oil of the steering pump 103 enters the oil passage P2 through the second oil inlet EF, enters the oil passage P4 through the third one-way valve 440, enters the small cavity of the rotating bucket oil cylinder 303 through the rotating bucket unloading cavity bkd of the rotating bucket control valve 350, and is controlled to unload. Specifically, the oil passage P4 is communicated with a rotary hopper unloading cavity bkd through an oil passage rbkd, and a rotary hopper collecting cavity bkl is communicated with a second oil return oil passage T1 through an oil passage tbk1, so that rotary hopper unloading of the loader is realized.

The valve body 110 is provided with a shuttle valve 120, the shuttle valve 120 is provided with a first oil port, a second oil port and a third oil port, the first oil port is communicated with the regulating oil passage on the movable arm valve rod 320, the second oil port is communicated with the regulating oil passage on the rotating bucket valve rod 360, and the third oil port is communicated with the load sensing oil port LS. Optionally, the first damping hole and the second damping hole on the movable arm valve rod 320 are an oil port lsb1 and an oil port lsbr, and the movable arm valve rod 320 is further provided with an oil port lsb, an oil passage lsb3 and an oil passage lsbt; the oil port lsb1 and the oil port lsbr are connected with the oil port lsb through an internal oil passage of the boom valve stem 320, enter the first oil port of the shuttle valve 120 through the lsb3, and are communicated with the load sensing oil passage ls through the third oil port of the shuttle valve 120. The oil port lsb is communicated with the first oil return oil channel T0 through the oil channels lsb3 and lsbt. Namely, the oil in the load sensing oil port LS is communicated with the first oil return passage T0 in a normal state (non-working state).

The first damping hole and the second damping hole on the rotating hopper valve rod 360 are an oil port lsbk1 and an oil port lsbk r, and the rotating hopper valve rod 360 is further provided with an oil port lsbk, an oil channel lsbk3 and an oil channel lsbk t; the oil port lsbk1 and the oil port lsbk r are connected with the oil port lsbk through an internal oil passage of the rotating bucket valve rod 360, enter the second oil port of the shuttle valve 120 through an oil passage lsb3, and are communicated with the load sensing oil passage ls through the third oil port of the shuttle valve 120. The oil port lsbk is communicated with the first oil return channel T0 through oil channels lsbk3 and lsbk T. Namely, the oil in the load sensing oil port LS is communicated with the first oil return passage T0 in a normal state (non-working state).

Optionally, the valve body 110 is provided with a floating control valve 130, a floating oil replenishing valve 140 and an oil replenishing valve 141, and the floating oil replenishing valve 140 and the oil replenishing valve 141 are used for replenishing oil to the small cavity of the working cylinder. It can be understood that in the process of unloading the rotating hopper, the small cavity of the rotating hopper oil cylinder 303 is vacuumized, and the rotating hopper unloading cavity bkd is connected with the small cavity of the rotating hopper oil cylinder 303 and is lower than the atmospheric pressure; the hydraulic oil in the large cavity of the rotating bucket cylinder 303 returns to the second oil return oil passage T1 through the rotating bucket collecting cavity bkl, the rotating bucket valve rod 360 and the oil passage tbkl, and because of the backpressure PT1 generated by the backpressure valve 410, the oil return of the second oil return oil passage T1 pushes the valve core of the oil supply valve 141 to enter the rotating bucket discharging cavity bkd, so that the phenomenon that the sealing element is burnt due to the vacuum in the small cavity of the rotating bucket cylinder 303 is avoided.

Similarly, when the boom descends, a vacuum occurs in the small cavity of the boom cylinder 301, and the boom descending cavity bd is connected to the small cavity of the boom cylinder 301 and is lower than the atmospheric pressure; the hydraulic oil in the large cavity of the boom cylinder 301 returns to the second oil return passage T1 through the boom ascending cavity bl, the boom valve rod 320 and the oil passage tbl, and due to the backpressure PT1 generated by the backpressure valve 410, the oil return of the second oil return passage T1 pushes the valve core of the floating oil compensation valve 140 open to enter the boom descending cavity bd, so that the situation that the small cavity of the boom cylinder 301 is vacuumized and the sealing element is burned is avoided.

Optionally, the floating control valve 130 is connected to the floating oil compensation valve 140, and if the floating control valve 130 is in operation, the floating oil compensation valve 140 has a floating function, and may be used to make the boom in a floating state during the boom descending process. If the floating control valve 130 does not work, the floating oil supply valve 140 may perform an oil supply function to supply oil to the small cavity of the boom cylinder 301.

Optionally, a main safety valve 170 is further disposed on the valve body 110, a high-pressure end of the main safety valve 170 is communicated with the oil passage P2, and the other end of the main safety valve is communicated with the first oil return passage T0, so as to prevent the system pressure from being too high, and a pressure value set by the main safety valve 170 is higher than a pressure value set by the relief valve 160.

The multi-way valve 100 provided in this embodiment operates according to the following principle:

the first working condition is as follows: the engine is not started and the working pump 101 and the steering pump 103 are not operated. The boom valve stem 320 is in a neutral position by the second spring 330, and the boom control valve 310 is in a closed state. The rotary bucket valve rod 360 is in the neutral position under the action of the third spring 370, and the rotary bucket control valve 350 is in the closed state. The switching valve stem 201 is in a left position, i.e., an open state, under the action of the first spring 203.

The second working condition is as follows: after the engine is started, the steering system does not steer; the pilot valve 105 is not operated, and the movable arm valve rod 320 and the rotary bucket valve rod 360 are in the middle positions; the oil of the steering pump 103 enters the second oil inlet EF of the multi-way valve 100 through the priority valve 106, enters the oil passage P2 through the oil passage EF, enters the oil passage P3 through the second check valve 430, and enters the oil passage P4 through the third check valve 440. At this time, the LS oil port is communicated with the first oil return passage T0, the steering pump 103 enters the full hydraulic steering gear 401 through the load sensing oil passage LS of the priority valve 106 under the control of the built-in regulator according to the minimum pressure and the minimum flow rate set by the regulator of 0.5 to 2L/min, and oil is returned through the oil return pipe of the steering gear 401, thereby saving energy. Alternatively, the set pressure of the regulator is generally 16 to 24bar, and the pressure simultaneously pushes the switching valve rod 201 to move to the right, the switching valve 200 is in the closed state, and the incoming oil of the working pump 101 enters the first return oil passage T0 through the second oil passage rst and is unloaded at a low pressure.

The third working condition is as follows: after the engine is started, the steering system does not steer; when the pilot valve 105 is operated, for example, the movable arm operating lever is operated to lift, the first pilot oil inlet xA2 enters pilot oil, the movable arm valve rod 320 is controlled to move leftwards, oil liquid of the steering pump 103 enters the P3 oil channel and enters the movable arm ascending cavity bl through the oil channel rbl, and namely, oil enters a large cavity of the movable arm oil cylinder 301; the hydraulic oil in the small cavity of the boom cylinder 301 enters the boom descending cavity bd of the boom control valve 310, and is communicated with the first oil return passage T0 through the oil passage tb2 for oil return. Meanwhile, as the movable arm valve stem 320 moves, the oil passage lsbt is closed, and as the movable arm, the bucket and the material have weights, the pressure oil in the movable arm ascending cavity bl enters the internal oil passage of the movable arm valve stem 320 through the oil port lsb1 on the left side of the movable arm valve stem 320, and enters the load sensing oil passage ls through the oil port lsb, the oil passage lsb3 and the shuttle valve 120.

A part of the pressure oil entering the load sensing oil passage LS is communicated with the system shuttle valve 109 through the load sensing oil port LS, and acts on a spring cavity of the compensator 104 of the steering pump 103 through the x oil passage, so that the displacement of the steering pump 103 is increased, and the flow demand of the hydraulic system of the execution module is met. The steering pump 103 can be a variable displacement plunger pump, and the pressure is higher.

The pressure oil introduced into the load sensing oil passage ls enters the second chamber c1s of the switch valve 200 in another portion, and the first spring 203 acts on the right side of the switch valve stem 201. Setting delta Pbl as the pressure difference between the oil passage P3 and the boom ascending cavity bl, when the delta Pbl pressure is smaller than or equal to the elastic force of the first spring 203, the switching valve rod 201 is positioned on the left side, the switching valve 200 is opened, the oil from the working pump 101 enters the oil passage P1 through the first oil passage rsi, the first check valve 420 is opened to enter the oil passage P2, the second check valve 430 is opened to enter the oil passage P3, namely the switching valve rod 201 controls the working pump 101 to merge into the execution module hydraulic system, so as to accelerate the execution module boom lifting.

When an operator controls the lifting state of the movable arm in a micro-motion mode, the delta Pbl pressure is greater than the elastic force of the first spring 203, the switching valve rod 201 is pushed to be positioned on the right side, the switching valve 200 is closed, incoming oil of the working pump 101 enters the first oil return channel T0 through the second oil channel rst for oil return, and the switching valve rod 201 controls the unloading of the working pump 101 to achieve energy saving of the hydraulic system.

In the process of lifting the movable arm, if the pressure oil in the movable arm lifting cavity bl is unloaded when being higher than the set pressure of the overflow valve 160, the pressure of the hydraulic oil in the second chamber c1s on the switching valve 200 is reduced, the switching valve rod 201 is pushed to the right side under the action of the high-pressure oil in the first chamber cs1, the switching valve 200 is closed, the working pump 101 is unloaded, and the energy saving of a hydraulic system is realized when the movable arm oil cylinder 301 works at high pressure and small flow.

Similarly, after the engine is started, the steering system is not steered; the pilot valve 105 performs operation, for example, the boom operating lever is operated to lift, the second pilot oil inlet xB2 enters pilot oil, the boom valve rod 320 is controlled to move rightwards, oil of the steering pump 103 enters the P4 oil passage and enters the boom ascending cavity bl through the oil passage rbd, that is, oil enters the small cavity of the boom oil cylinder 301; the hydraulic oil in the large cavity of the boom cylinder 301 enters the boom raising cavity bl of the boom control valve 310, and is communicated with the second oil return passage T1 through the oil passage tb1 to return oil. Meanwhile, as the boom valve stem 320 moves, the oil passage lsbt is closed, and as the weight of the boom, the bucket and the material exists, the pressure oil in the boom descending cavity bd enters the internal oil passage of the boom valve stem 320 through the oil port lsbr on the right side of the boom valve stem 320, and enters the load sensing oil passage ls through the oil port lsb, the oil passage lsb3 and the shuttle valve 120.

A part of the pressure oil entering the load sensing oil passage LS is communicated with the system shuttle valve 109 through the load sensing oil port LS, and acts on a spring cavity of the compensator 104 of the steering pump 103 through the x oil passage, so that the displacement of the steering pump 103 is increased, and the flow demand of the hydraulic system of the execution module is met.

The pressure oil introduced into the load sensing oil passage ls enters the second chamber c1s of the switch valve 200 in another portion, and the first spring 203 acts on the right side of the switch valve stem 201. Setting delta Pbl as the pressure difference between the oil passage P3 and the boom ascending cavity bl, when the delta Pbl pressure is smaller than or equal to the elastic force of the first spring 203, the switching valve rod 201 is positioned on the left side, the switching valve 200 is opened, the oil from the working pump 101 enters the oil passage P1 through the first oil passage rsi, the first check valve 420 is opened to enter the oil passage P2, the second check valve 430 is opened to enter the oil passage P3, namely the switching valve rod 201 controls the working pump 101 to merge into the hydraulic system of the execution module, so as to accelerate the boom descending of the execution module.

When an operator controls the descending state of the movable arm in a micro-motion mode, the delta Pbl pressure is greater than the elastic force of the first spring 203, the switching valve rod 201 is pushed to be positioned on the right side, the switching valve 200 is closed, incoming oil of the working pump 101 enters the first oil return channel T0 through the second oil channel rst for oil return, and the switching valve rod 201 controls the unloading of the working pump 101 to achieve energy saving of the hydraulic system.

In the boom descending process, if the pressure oil in the boom descending cavity bd is unloaded when being higher than the set pressure of the relief valve 160, the pressure of the hydraulic oil in the second chamber c1s on the switching valve 200 is reduced, the switching valve rod 201 is pushed to the right side under the action of the high-pressure oil in the second chamber c1s, the switching valve 200 is closed, the working pump 101 is unloaded, and the energy saving of the hydraulic system is realized when the boom cylinder 301 works at a high pressure and a small flow.

When the execution module descends, a small cavity of the movable arm cylinder is vacuumized, and a movable arm descending cavity bd is connected with the small cavity of the movable arm cylinder 301 and is lower than the atmospheric pressure; the hydraulic oil in the large cavity of the movable arm cylinder 301 returns to the second oil return passage T1 through the movable arm ascending cavity bl, the movable arm valve rod 320 and the oil passage tbl, and due to the back pressure PT1 generated by the back pressure valve 410, the oil return of the second oil return passage T1 pushes the valve core open to enter the movable arm descending cavity bd for oil supplement, so that the small cavity of the movable arm cylinder 301 is prevented from being vacuumized and burning a sealing element.

The fourth working condition is as follows: after the engine is started, the steering system does not steer; the pilot valve 105 is operated, if the bucket is operated by the rotating bucket operating lever, the third pilot oil inlet xA1 enters pilot oil, the rotating bucket valve rod 360 is controlled to move leftwards, oil of the steering pump 103 enters the P4 oil channel and enters the rotating bucket cavity bkl through the oil channel rbkl, and the oil enters the large cavity of the rotating bucket oil cylinder 303; the hydraulic oil in the small cavity of the rotating bucket oil cylinder 303 enters the rotating bucket unloading cavity bkd and is communicated with the first oil return channel T0 through the oil channel Tbk2 for oil return. Meanwhile, as the rotating bucket valve rod 360 moves, the oil channel lsbkt is closed, and as the rotating bucket has a load, pressure oil in the rotating bucket cavity bkl enters an internal channel of the rotating bucket valve rod 360 through the oil port lsbk1 on the left side of the rotating bucket valve rod 360 and enters the load sensing oil channel ls through the oil port lsbk, the oil channel lsbk3 and the shuttle valve 120. One side of the pressure oil is communicated with a system shuttle valve 109 through a load sensing oil port LS, the pressure oil acts on a spring cavity of a compensator 104 of the steering pump 103 through a system x oil channel, the displacement of the steering pump 103 is increased, and the flow demand of a hydraulic system of an execution module is met. The other side of the pressurized oil enters the second chamber c1s of the switch valve 200, and cooperates with the first spring 203 on the right side of the switch valve stem 201. Setting delta Pbk1 as the pressure difference between the oil passage P4 and the rotating bucket collecting cavity bkl, when the delta Pbkl pressure is smaller than or equal to the elastic force of the first spring 203, the switching valve rod 201 is positioned on the left side, the switching valve 200 is opened, the incoming oil of the working pump 101 enters the oil passage P1 through the first oil passage rsi, opens the first one-way valve 420 to enter the oil passage P2, and enters the oil passage P4 through the third one-way valve 440, namely the switching valve rod 201 controls the working pump 101 to flow into the hydraulic system of the execution module, so as to accelerate the rotating bucket collecting of the execution module.

When an operator controls the bucket collecting state in a micro-motion mode, the pressure delta Pbkl is larger than the elastic force of the first spring 203, the switching valve rod 201 is pushed to be positioned on the right side, the switching valve 200 is closed, the incoming oil of the working pump 101 enters the first oil return oil channel T0 through the second oil channel rst for oil return, and the switching valve rod 201 controls the unloading of the working pump 101 to achieve energy saving of the hydraulic system.

If the pressure oil of the bucket receiving cavity bk1 is unloaded when being higher than the set pressure of the overflow valve 160, the pressure of the hydraulic oil in the second chamber c1s on the switching valve 200 is reduced, the switching valve rod 201 is pushed to the right side under the action of the high-pressure oil in the first chamber cs1, the switching valve 200 is closed, the working pump 101 is unloaded, the bucket cylinder works at high pressure and low flow, and the energy conservation of a hydraulic system is realized.

After the engine is started, the steering system does not steer; the pilot valve 105 performs a manipulation, such as a manipulation of discharging the rotating bucket, and the fourth pilot oil inlet xB1 enters the pilot oil, and the control principle thereof is similar to that described above and will not be described in detail here. It should be noted that when the rotating bucket of the execution module discharges, the small cavity of the rotating bucket oil cylinder 303 is vacuum, the oil supplementing valve 141 can supplement oil to the small cavity of the rotating bucket oil cylinder 303, the oil supplementing principle is similar to the oil supplementing principle of the small cavity of the movable arm oil cylinder 301, and the situation that the sealing member is burned due to the vacuum of the small cavity of the rotating bucket oil cylinder 303 is avoided.

In addition, in the descending process of the movable arm, the floating control valve 130 and the floating oil supplementing valve 140 are arranged to enable the execution module to be in a floating state, and the floating control pressure set value is 25-30 bar; the settling amount of the boom cylinder 301 is reduced by the arrangement of the floating oil replenishment valve 140. In the descending process of the movable arm, the arrangement of the quick descending valve can also enable the movable arm oil cylinder 301 of the execution module to directly return oil, so that the quick descending is realized, the hydraulic control system is suitable for a hydraulic control system of a large-sized loader, and the working efficiency is improved.

Optionally, the multi-way valve 100 further comprises a pressure reducing valve 460, the pressure reducing valve 460 being disposed on the control oil path between the pilot oil inlet and the control chamber. In this embodiment, the pressure reducing valve 460 is disposed on the control oil path between the third pilot oil inlet xA1 and the large cavity of the rotating bucket oil cylinder 303, so that the composite operation of the movable arm and the rotating bucket can be realized, the rotating bucket filling rate is high, the operation efficiency is high, and the operation labor intensity of a driver is greatly reduced. In this embodiment, the pressure reducing valve 460 is disposed in the control end cap of the big cavity of the rotating bucket, and has a compact structure.

It should be noted that the switching valve rod 201 in this embodiment is automatically controlled by a hydraulic system, and in other alternative embodiments, an external electric control or external hydraulic control mode may also be adopted to implement the connection and disconnection of the switching valve 200, so as to implement the confluence and unloading of the working pump 101. The spatial position relationships of the switching valve rod 201, the movable arm valve rod 320, the rotary bucket valve rod 360, the overflow valve 160, the floating oil replenishing valve 140, the floating control valve 130, the oil replenishing valve 141, the shuttle valve 120, the quick descent valve and the like in the embodiment can be flexibly set and arranged according to actual needs, and the oil passages are ensured to be communicated according to the principle contemplated in the application, and the spatial position relationships are not particularly limited. The schematic diagram of the control principle of the hydraulic system only shows the principle of oil passage communication, and is not used for limiting the position of each hydraulic element. The pilot valve 105, the pilot oil supply valve, the brake valve, and the like shown in fig. 1 have conventional structures, and do not belong to the improvement point of the present application, and therefore, they are not described in detail.

The embodiment also provides a hydraulic system, which comprises a working pump 101, a steering pump 103, an execution module and the multi-way valve 100, wherein the working pump 101 and the steering pump 103 are respectively connected with the multi-way valve 100, the multi-way valve 100 is connected with the execution module, the hydraulic system is suitable for engineering machinery such as a loader, the automatic unloading or confluence function of the working pump 101 can be realized when the execution module is in a micro-motion state and a full-speed motion state, the flow distribution is optimized, and the energy conservation of the hydraulic system is realized. The high-pressure small-flow work and the low-pressure large-flow work of a hydraulic system can be realized, and the energy-saving effect is obvious.

To sum up, the embodiment of the present invention provides a multiway valve 100 and a hydraulic system, which have the following beneficial effects:

the multi-way valve 100 integrates the conversion valve 200 on the valve body 110, so that the function of automatic unloading or confluence of the working pump 101 can be realized when the inching state and the full-speed motion state of the execution module are realized, the distribution of flow is optimized, and the energy conservation of a hydraulic system is realized. The high-pressure small-flow work and the low-pressure large-flow work of the hydraulic system can be realized, and the energy-saving effect is obvious. The floating oil supplementing valve 140, the floating control valve 130 and the oil supplementing valve 141 are arranged together, and integrated arrangement reduces pipelines, leakage and sedimentation amount. The quick descending valve can realize quick descending of the movable arm, is suitable for a hydraulic control system of a large-sized loader, and improves the working efficiency. The whole structure is compact, the cost is low, and the energy-saving efficiency is high.

The embodiment of the utility model provides a hydraulic system is applicable to engineering machine tools such as loader, can realize when execution module fine motion state and full speed motion state, realizes the function of the automatic off-load of working pump 101 or confluence, optimizes the distribution of flow, realizes that hydraulic system is energy-conserving. The high-pressure small-flow work and the low-pressure large-flow work of the hydraulic system can be realized, and the energy-saving effect is obvious.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The multi-way valve is characterized by comprising a valve body, and a change-over valve and a working valve group which are arranged on the valve body, wherein a first oil inlet (P) and a second oil inlet (EF) are formed in the valve body, the first oil inlet (P) is used for being communicated with a working pump, and the second oil inlet (EF) is used for being communicated with a steering pump;

the switching valve is provided with a switching valve rod, a first chamber and a second chamber, and the switching valve rod can move in the first chamber and the second chamber; the working valve group is provided with a working valve oil inlet which is communicated with the first cavity, the valve body is provided with a load sensing oil passage (ls), and the load sensing oil passage (ls) is communicated with the second cavity; if the pressure difference between the oil inlet of the working valve and the first cavity is smaller than or equal to a first preset value, the conversion valve rod is located at a first position, so that an oil path between the first oil inlet (P) and the oil inlet of the working valve is communicated; if the pressure difference between the oil inlet of the working valve and the first cavity is larger than the first preset value, the conversion valve rod is located at the second position, so that the oil path between the first oil inlet (P) and the oil inlet of the working valve is cut off.

2. The multiway valve of claim 1, wherein the valve body is provided with an oil return port (T), a pilot oil inlet and a load sensing oil port (LS), the pilot oil inlet is used for being communicated with the pilot valve, and the oil return port (T) and the load sensing oil port (LS) are respectively communicated with an oil tank;

the working valve group is provided with a control cavity, a working cavity and a working valve rod, wherein a working valve oil inlet is respectively communicated with a first oil inlet (P) and a second oil inlet (EF), a pilot oil inlet is communicated with the control cavity, pilot oil enters the control cavity from the pilot oil inlet, and is used for driving the working valve rod to move so as to enable the working valve oil inlet to be communicated with the working cavity, and the working cavity is used for being connected with an execution module.

3. The multiway valve of claim 2, wherein the oil inlet of the diverter valve communicates with the first oil inlet (P), and the oil outlet of the diverter valve communicates with the set of work valves; the oil inlet of the change-over valve is communicated with the oil outlet of the change-over valve through the first oil duct (rsi), and the oil inlet of the change-over valve is communicated with the oil return port of the change-over valve through the second oil duct (rst).

4. The multiple-way valve as claimed in claim 3, wherein a first elastic member is disposed at one end of the switching valve stem, and the first elastic member is disposed in the second chamber; if the pressure difference between the pressure in the first chamber and the pressure in the second chamber is smaller than or equal to the elastic force of the first elastic piece, the switching valve rod is in a first position, so that the oil inlet of the switching valve is communicated with the oil outlet of the switching valve through the first oil passage (rsi); if the pressure difference between the pressure in the first cavity and the pressure in the second cavity is larger than the elastic force of the first elastic piece, the switching valve rod moves to the second position, so that the oil inlet of the switching valve is communicated with the oil return port of the switching valve through the second oil passage (rst).

5. The multiple-way valve according to claim 2, wherein the control chamber is provided with a second elastic member connected to the working stem to place the working stem in a third position or a fourth position;

6. The multi-way valve according to claim 5, wherein the working valve rod is provided with an adjusting oil passage, the adjusting oil passage comprises a first damping hole, a second damping hole and an internal oil passage, the first damping hole is communicated with the first working cavity, the second damping hole is communicated with the second working cavity, the first damping hole and the second damping hole are respectively communicated with the internal oil passage, and the internal oil passage is communicated with the load sensing oil port.

7. The multi-way valve according to claim 5, wherein the working valve group comprises a boom control valve and a bucket control valve, the first oil inlet (P) is connected with the boom control valve and the bucket control valve through the switching valve respectively, and the second oil inlet (EF) is connected with the boom control valve and the bucket control valve respectively; the working valve rod comprises a movable arm valve rod and a rotary hopper valve rod, the movable arm valve rod is movably arranged on the movable arm control valve, and the rotary hopper valve rod is movably arranged on the rotary hopper control valve;

8. The multiway valve as recited in claim 7, wherein the valve body is provided with a first oil return passage (T0) and a second oil return passage (T1); a back pressure valve is arranged on the valve body, and the second oil return channel (T1) is communicated with the first oil return channel (T0) through the back pressure valve;

in the movable arm control valve, the first working cavity comprises a movable arm ascending cavity which is used for being connected with a large cavity of a movable arm oil cylinder; the second working cavity comprises a movable arm descending cavity and is used for being connected with a small cavity of the movable arm oil cylinder; the return oil of the movable arm ascending cavity is communicated with the second return oil duct (T1), and the return oil of the movable arm descending cavity is communicated with the first return oil duct (T0); the first oil return channel (T0) is communicated with the oil return opening (T).

9. The multiplex valve as defined in claim 8, wherein in said bucket control valve, said first working chamber includes a bucket receiving chamber for connection with a large chamber of a bucket cylinder; the second working cavity comprises a rotating hopper discharging cavity which is used for being connected with a small cavity of the rotating hopper oil cylinder; the return oil of the rotary hopper receiving cavity is communicated with the second oil return oil duct (T1), and the return oil of the rotary hopper discharging cavity is communicated with the first oil return oil duct (T0).

10. The multi-way valve as claimed in claim 7, wherein a shuttle valve is disposed on the valve body, the shuttle valve has a first oil port, a second oil port and a third oil port, the first oil port is communicated with the regulating oil passage on the movable arm valve rod, the second oil port is communicated with the regulating oil passage on the rotating bucket valve rod, and the third oil port is communicated with the load sensing oil port.

11. The multiway valve according to claim 2, wherein an overflow valve is arranged on the valve body, a high-pressure cavity of the overflow valve is communicated with the load sensing oil passage (ls), and an oil return port of the overflow valve is communicated with the oil return port (T).

12. The multiplex valve as defined in any one of claims 2 to 11, further comprising a pressure relief valve disposed on the control oil path between the pilot oil inlet and the control chamber.

13. A hydraulic system, comprising a working pump, a steering pump, an actuator module and a multi-way valve according to one of claims 1 to 12, the working pump and the steering pump being connected to the multi-way valve, respectively, and the multi-way valve being connected to the actuator module.