CN113898017A

CN113898017A - Multi-way valve and excavator

Info

Publication number: CN113898017A
Application number: CN202111183535.3A
Authority: CN
Inventors: 周启迪; 蒋淋; 罗炎热
Original assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Changde Zhonglian Zhongke Hydraulic Co ltd
Priority date: 2021-10-11
Filing date: 2021-10-11
Publication date: 2022-01-07

Abstract

The invention relates to a hydraulic valve, and discloses a multi-way valve and an excavator, wherein the multi-way valve comprises a head joint (1), a plurality of working joints which are sequentially arranged, a pilot oil way (100), an oil inlet oil way (101) which communicates the head joint (1) with each working joint, and an oil return oil way (102) which communicates the head joint (1) with each working joint, wherein the working joints comprise main valve cores, the control ends of the main valve cores are provided with proportional control valves connected with the pilot oil way (100), and priority oil ways are arranged in part of the main valve cores of the working joints so as to increase the flow rates distributed by the working joints and the working joints arranged in front of the working joints. The multi-way valve has high flow distribution precision, does not need to be provided with a compensation valve, and has a simple structure.

Description

Multi-way valve and excavator

Technical Field

The invention relates to a hydraulic valve, in particular to a multi-way valve. In addition, still relate to an excavator.

Background

The small excavator belongs to a typical multi-actuator system, and is characterized in that a plurality of actuators perform parallel actions and the load changes frequently, and compared with a large excavator, the application scene is more variable, so that a hydraulic system of the small excavator is required to have a better flow distribution characteristic to improve the operation performance of a main engine, and therefore, a load sensitive multi-way valve is adopted in most of hydraulic systems of the small excavator at present.

The load-sensitive multi-way valve mainly comprises a head-tail connection and all work connections, wherein all work connection oil ways are connected in a parallel connection mode, and actions of all actuators of the excavator, such as movable arms, bulldozing, bucket rods, buckets, rotation, left walking, right walking and the like, are independently realized.

Because most of the existing mini-excavators adopt the multi-way valve with the load sensitivity compensated after the valve, the flow control precision is limited; in addition, a compensation valve is required to be independently installed in each working connection of the conventional load-sensitive multi-way valve, so that the structure is complex and the cost is high.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a multi-way valve which has higher flow distribution precision, does not need to be provided with a compensation valve and has a simpler structure.

A further object of the present invention is to provide an excavator having a high flow rate distribution accuracy.

In order to solve the technical problem, a first aspect of the invention provides a multiway valve, which includes a header, a plurality of sequentially arranged work couples, a pilot oil path, an oil inlet path communicating the header with each of the work couples, and an oil return path communicating the header with each of the work couples, wherein the work couples include a main valve core, a control end of the main valve core is provided with a proportional control valve connected with the pilot oil path, and a priority oil path is provided in a part of the main valve cores of the work couples, so as to increase the flow rate distributed by the work couples and the work couples arranged in front of the work couples.

Optionally, each of the work couplings includes a left travel coupling, a right travel coupling, a boom coupling, a bucket coupling, a dozer coupling, and a swing coupling, which are sequentially communicated with the oil inlet passage.

Specifically, the bucket rod linkage comprises a first bucket rod oil connecting port, a second bucket rod oil connecting port, a bucket rod retaining valve and the main valve core, the main valve core comprises a first oil port, a second oil port and an oil inlet which are connected with the oil inlet oil way, a third oil port which is connected with the first bucket rod oil connecting port, a fourth oil port which is connected with the second bucket rod oil connecting port and an oil return port which is connected with the oil return oil way, and the bucket rod retaining valve is located on the oil way between the third oil port of the main valve core and the first bucket rod oil connecting port.

Further, an arm holding pilot valve is connected to a control chamber of the arm holding pilot valve, and a control chamber of the arm holding pilot valve is connected to a control oil path at one end of the main valve core.

Optionally, the arm linkage further includes an arm regeneration structure, and when the arm is in a negative load state, the arm regeneration structure enables part or all of the returned hydraulic oil to flow from the rod cavity of the oil cylinder to the rodless cavity thereof.

Specifically, the bucket rod regeneration structure comprises a bucket rod regeneration oil path and a bucket rod regeneration valve, wherein the bucket rod regeneration valve is located between an oil return port of the main valve core and an oil return path, and the bucket rod regeneration oil path is located between the oil return port of the main valve core and an oil inlet of the main valve core so that hydraulic oil can flow from a rod cavity of the oil cylinder to a rodless cavity of the oil cylinder.

Further, the bucket rod coupling also comprises a bucket rod regeneration control valve connected with a control cavity of the bucket rod regeneration valve.

Specifically, the arm regeneration structure includes an arm regeneration passage disposed within the main spool.

Optionally, the boom linkage includes the main spool and a boom-holding valve on an oil path between the main spool and a cylinder.

Specifically, a control chamber of the boom holding pilot valve is connected with a boom holding pilot valve, and a control chamber of the boom holding pilot valve is connected with a control oil path at one end of the main valve core.

Optionally, the boom linkage further comprises a boom regeneration structure, and when the boom descends, the boom regeneration structure enables the returned hydraulic oil to partially or completely flow from the rodless cavity of the oil cylinder to the rod cavity of the oil cylinder.

Specifically, the movable arm regeneration structure comprises a movable arm regeneration oil path and a movable arm regeneration valve, wherein the movable arm regeneration valve is located between an oil return port of the main valve core and the oil return oil path, and the movable arm regeneration oil path is located between the oil return port of the main valve core and an oil inlet of the main valve core so that hydraulic oil can flow from a rodless cavity of the oil cylinder to a rod cavity of the oil cylinder.

Further, the boom linkage further comprises a boom regeneration control valve connected with a control chamber of the boom regeneration valve.

Specifically, the boom regeneration structure includes a boom regeneration passage disposed within the main spool.

Optionally, the main valve core of the right walking link, the main valve core of the arm link, and the main valve core of the boom link are provided with the priority oil passages.

Specifically, a damping valve is arranged on the priority oil passage.

Optionally, the first joint comprises a stop valve and a control valve, and a control cavity of the stop valve is connected with the pilot oil path through the control valve.

A second aspect of the present invention provides an excavator provided with the multi-way valve according to any one of the above aspects.

Through the technical scheme, the invention has the following beneficial effects:

the invention controls the flow of the main valve core through the proportional control valve, cancels a pressure compensation valve in a load sensitive system in the prior art, does not need to process a complex signal oil duct or an external signal pipeline in a valve body, leads the processing and the assembly of the multi-way valve to be more efficient, and also ensures the good speed regulation characteristic. And the main valve core of part of the working units is internally provided with a priority oil duct, so that the working units provided with the priority oil ducts and the working units arranged in front of the working units can distribute more flow, the working units and the working units arranged in front of the working units correspond to the priority realization of the action of the working function, and the priority action sequence of the actuating mechanism corresponding to each working unit is determined, thereby not only ensuring the reasonable distribution of the flow during the composite action, but also simplifying the structure of the whole valve group.

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

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a hydraulic schematic of a multi-way valve according to an embodiment of the present invention;

FIG. 2 is a hydraulic schematic of an arm linkage according to an embodiment of the present invention;

FIG. 3 is a hydraulic schematic of a boom linkage according to an embodiment of the present invention;

FIG. 4 is a hydraulic schematic of the priority function of the multiplex valve of an embodiment of the present invention.

Description of the reference numerals

1 first-connection 11 stop valve

12 control valve 2 left walking coupler

3 right walking link and 4 bucket rod link

B4 first arm connecting oil port A4 second arm connecting oil port

First port of 41-bucket rod holding valve C1 bucket rod main valve core

Second port of C2 bucket rod main valve core, third port of C3 bucket rod main valve core

A fourth port P1 of the C4 bucket rod main valve core is connected with the oil inlet of the main valve core

T1 bucket rod main valve core oil return port 42 bucket rod holding pilot valve

43 arm regeneration oil path 44 arm regeneration valve

45 bucket rod regeneration control valve 5 movable arm linkage

51 boom holding valve 52 boom holding pilot valve

P2 oil inlet T2 of boom linkage main valve core oil return port

53 boom regeneration path 6 bucket linkage

7 bulldozing and 8 rotating combined link

9 damping valve 100 pilot oil circuit

101 oil inlet passage 102 oil return passage

103 oil drainage way

Detailed Description

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.

In the description of the present invention, it is first noted that, unless otherwise explicitly stated or limited, terms such as "mounted," "disposed," "connected," and the like are to be construed broadly, and for example, may be fixedly connected, detachably connected, or integrally connected; 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.

Furthermore, the terms "first", "second", "third", "fourth" 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 as "first", "second", "third", "fourth" may explicitly or implicitly include one or more of the features described.

It should be noted that the multi-way valve of the present invention belongs to the hydraulic field, and for those skilled in the art, the substantial technical concept lies in the hydraulic connection relationship. The related hydraulic components, such as the directional valve, the check valve, the damping valve, the relief valve, the cylinder, the hydraulic motor, etc., are well known to those skilled in the art and are common components in the existing hydraulic system, so that the hydraulic components will be only briefly described below. After understanding the technical concept of the present invention, those skilled in the art can also simply replace an oil path or a valve, etc. to implement the function of the multi-way valve of the present invention, which also belongs to the protection scope of the present invention.

Referring to fig. 1, the invention provides a multi-way valve, which comprises a header 1, a plurality of working headers, a pilot oil path 100, an oil inlet path 101 and an oil return path 102, wherein each working header is arranged in a certain sequence, the oil inlet path 101 is sequentially communicated with the header 1 and each working header, the oil return path 102 is sequentially communicated with the header 1 and each working header, each working header comprises a main valve core, a control end of the main valve core is provided with a proportional control valve, each proportional control valve is connected with the pilot oil path 100, the flow of the main valve core is controlled through the proportional control valve, a pressure compensation valve in the conventional load sensitive system is omitted, a complicated signal oil path or an external signal pipeline does not need to be processed in a valve body, the processing and the assembly of the multi-way valve are more efficient, and good speed regulation characteristics are also ensured. And moreover, a priority oil duct is arranged in the main valve core of part of the working couplings, the priority oil duct can enable the working coupling provided with the priority oil duct and the working coupling arranged in front of the working coupling to distribute more flow, the working function of the corresponding executing mechanism can be preferentially realized, the priority action sequence of each executing mechanism is determined by the position of each working coupling in the multi-way valve, the reasonable distribution of the flow during the composite action is ensured, and the structure of the whole valve group is simplified.

Preferably, the proportional control valve may be an electromagnetic proportional valve, the proportional control valve is connected to the pilot oil path 100 and the drain oil path 103, and when pilot oil is output to the control chamber at one end of the main valve element of the corresponding working connection through the proportional control valve, the pilot oil is input into the pilot oil path 100 from the pilot oil port Pp and flows to the main valve element of the corresponding working connection. The other end control cavity of the main valve core of the corresponding working connection flows to the oil drainage oil path 103 through the corresponding proportional control valve and flows out from an oil drainage port Dr of the oil drainage oil path 103.

Taking a small-sized hydraulic excavator as an example, referring to fig. 1, each working link of the multi-way valve of the present invention may be a left walking link 2, a right walking link 3, an arm link 4, a movable arm link 5, a bucket link 6, a dozer link 7, and a slewing link 8, and an oil inlet passage 101 sequentially passes through the head link 1, the left walking link 2, the right walking link 3, the arm link 4, the movable arm link 5, the bucket link 6, the dozer link 7, the slewing link 8, and the like. Furthermore, a standby link can be arranged in the multi-way valve and is used for being connected with a corresponding execution mechanism when a fault occurs, so that the normal operation of the hydraulic equipment is ensured, and the standby link can also be connected with execution mechanisms with other functions so as to realize corresponding working functions; the multiway valve can also be provided with a tail connector. The actuator mechanisms corresponding to the left walking link 2, the right walking link 3 and the revolving link 008 can be hydraulic motors, main valve cores of the hydraulic motors are Y-shaped neutral position functions, main valve cores of the other working links are O-shaped neutral position functions, and oil passages of all the working links are connected in series through the rest two ways of the main valve cores; the main spool may preferably be a three-position, six-way reversing valve.

It should be noted that each working channel controls the corresponding actuator to perform corresponding actions through the reversing of the main valve element, and for convenience of description, the left position function, the middle position function and the right position function of the main valve element are distinguished based on the arrangement orientation of the drawing in fig. 1.

The small hydraulic excavator mainly comprises the following common compound actions in operation:

(1) excavating: excavation is usually performed by a bucket cylinder or a stick cylinder, or by a combination of both. Therefore, the composite action of the bucket and the arm is mainly used in the process;

(2) full bucket lifting and rotating: after excavation is finished, the movable arm hydraulic cylinder jacks up the movable arm, the full bucket is lifted, and meanwhile, the hydraulic motor is rotated to enable the rotary table to turn to an unloading position, and at the moment, the composite action of the movable arm and rotation is mainly performed;

(3) unloading: when the bucket rotates to an unloading position, the rotary table is braked, the unloading radius is adjusted by the bucket rod hydraulic cylinder, then the bucket hydraulic cylinder retracts, and the bucket is unloaded, wherein the bucket rod and the bucket are mainly subjected to combined action at the moment;

(4) returning an empty bucket: and after unloading is finished, the rotary table reversely rotates, the movable arm hydraulic cylinder is matched with the bucket rod hydraulic cylinder, the empty bucket is placed to a new excavation point, and the rotation and the movable arm or the bucket rod perform combined action at the moment.

(5) The whole machine moves the operating mode: and moving the whole machine to a proper working position.

When the host machine carries out excavation and unloading actions, in order to improve the working efficiency, the speed of retraction of the bucket rod needs to be increased; when the bucket is lifted and rotated fully, the bucket generally rotates while lifting the movable arm, and the lifting speed of the large arm is generally required to be increased, so that the situation that the large arm rotates too much to touch the side of the excavation pit when the large arm is not lifted is avoided, and similarly, when the empty bucket returns, the actions of the bucket rod and the movable arm are prioritized; when the whole machine moves, in order to guarantee moving speed and driving safety, oil is preferentially provided for the left walking unit 2 and the right walking unit 3, the operation efficiency is improved by accelerating the walking forward or backward speed, and the operation safety is guaranteed by decelerating all other actions. Thus, in general, the priorities of the various actions are ordered from large to small as: the forward or backward movement of the left and right travel, the inward retraction of the arm, the raising of the boom, and the bucket, dozing, and turning.

In contrast, referring to fig. 4, priority oil passages may be provided in the main valve of the right travel link 3, the main valve of the arm link 4, and the main valve of the boom link 5. The priority oil passage is provided with a damping valve 9, specifically, referring to fig. 3, in order to ensure the moving speed and driving safety of the whole machine, a damping valve 9 may be provided in an oil passage on the main spool of the right walking link 3 where the oil-intake oil passage 101 passes through the right walking link 3 and goes back to the continuous working link (the arm link 4 in the embodiment shown in fig 1), namely, a damping valve 9 is arranged in the corresponding oil duct when the main valve core of the right walking joint 3 is positioned at the left position function and the right position function, this design makes it possible to reduce the flow rate of the working fluid flowing to the rear of the right-hand walking section 3, that is, when the main valve core of the right walking unit 3 moves to a left position function or a right position function, the oil inlet oil path 101 preferentially provides oil for the left walking unit 2 and the right walking unit 3, so that the walking forward or backward speed is increased to improve the operation efficiency, meanwhile, all the actions of the rest of the work units corresponding to the executing mechanism are decelerated to ensure the operation safety. Similarly, a damping valve 9 may be provided in an oil passage through which the oil inlet passage 101 passes through the arm link 4 (at this time, the main valve element of the arm link 4 is in the right position function) and flows to the main valve element of the arm link 4 of the subsequent working link, so that, during the excavation and unloading operations, the oil inlet passage 101 preferentially supplies oil to the arm link 4, and the speed of retraction of the arm is increased; the damping valve 9 can be arranged in an oil duct, wherein the oil inlet oil path 101 penetrates through the movable arm linkage 5 (at the moment, the main valve core of the movable arm linkage 5 is in a right position function) and flows to the main valve core of the movable arm linkage 5 of the subsequent working linkage, so that when the full bucket lifting and rotating, the damping valve 9 can realize that the oil inlet oil path 101 provides more oil for a rodless cavity of a movable arm oil cylinder, the lifting speed of the large arm is improved, and the situation that the large arm touches the side of the digging pit due to too many rotations under the non-lifting state of the large arm is avoided.

In the above, for the common combined action in the operation of the small hydraulic excavator, a technical scheme of implementing action priority functions such as forward or backward movement of left and right walking, arm retraction, boom raising and the like is designed; the common composite actions in the operation of different hydraulic machines are different, so that the implementation method of the priority function related to the technical scheme can be set on any working connection according to actual requirements for different hydraulic machines, and the sequence of each working connection can be adjusted to obtain the technical scheme of realizing the priority function of different purposes, which also belongs to the protection scope of the invention.

In a specific embodiment, referring to fig. 2, the arm linkage 4 includes a first arm linkage port B4, a second arm linkage port a4, an arm holding valve 41 and a main valve core, the main valve core includes a first port C1, a second port C2, an oil inlet P1, a third port C3, a fourth port C4 and an oil return port T1, the oil inlet passage 101 passes through the first port C1 of the main valve core and the second port C2 of the main valve core, and the oil inlet passage 101 is connected to the oil inlet P1 of the main valve core, a check valve is installed on an oil passage between the oil inlet passage 101 and the oil inlet P1 of the main valve core, so that hydraulic oil can flow from the oil inlet passage 101 to the oil inlet P1 of the main valve core in a single direction; a third oil port C3 of the main valve core is connected with a first bucket rod oil connecting port B4 through an bucket rod holding valve 41, a first bucket rod oil connecting port B4 is connected with a rod cavity of a corresponding actuating mechanism, a fourth oil port C4 of the main valve core is connected with a second bucket rod oil connecting port A4, and a second bucket rod oil connecting port A4 is connected with a rodless cavity of a corresponding actuating mechanism; the return port T1 of the main spool is connected to the return oil passage 102.

Further, an arm holding pilot valve 42 is attached to a control chamber of the arm holding valve 41, and the control chamber of the arm holding pilot valve 42 is connected to a control oil passage at one end of the main valve body when the main valve body is in the right position function. Wherein, the arm holding pilot valve 42 may preferably be a pilot operated directional control valve, such as a two-position two-way directional control valve.

Thus, when the arm does not act, the main valve core of the arm linkage 4 is in a neutral position function, at this time, the oil inlet P of the oil inlet oil path 101, the oil return port T of the oil return path 102, the oil path between the first arm oil coupling port B4 and the second arm oil coupling port a4 is cut off, the arm holding valve 41 is in a closed state, and the phenomenon that oil in the rod cavity of the arm cylinder leaks to other places to cause self sinking can be effectively prevented, so that the piston rod of the cylinder is effectively prevented from continuing to extend or shorten after extending to a set state, the piston rod is kept in a current state under the action of no other pressure oil, and the arm linkage 4 has a load holding function. Preferably, the arm holding valve 41 may be a cartridge valve.

When the bucket rod needs to perform outward swinging motion, the proportional control valve at the left end of the main valve core of the bucket rod linkage 4 is opened by a certain opening degree, a pressure signal of the pilot oil port Pp passes through the proportional control valve to push the main valve core to move, so that the main valve core is switched to a left position, the bucket rod retaining valve 41 is opened in the forward direction, an oil path between the oil inlet P of the oil inlet oil path 101 and the first bucket rod oil port B4 and an oil path between the second bucket rod oil port a4 and the oil return port T of the oil return path 102 are respectively communicated, oil enters the rod cavity of the corresponding execution mechanism, oil returns without the rod cavity, and outward swinging motion is realized.

When the bucket rod needs to perform adduction, the proportional control valve at the right end of the main valve core of the bucket rod linkage 4 is opened to a certain opening degree, a pressure signal of the pilot oil port Pp passes through the proportional control valve to push the main valve core to move, so that the main valve core is switched to a right position, the bucket rod keeps a control oil path of the pilot valve 42 to be communicated with a control oil path at the right end of the main valve core, the bucket rod keeps the pilot valve 42 to reverse under the action of a high-pressure signal, the bucket rod keeping valve 41 is reversely opened, an oil path between an oil inlet P of the oil inlet oil path 101 and a second bucket rod oil port A4 and an oil path between a first bucket rod oil port B4 and an oil return port T of the oil return path 102 are respectively communicated, and the bucket rod chamber of the corresponding to the rodless chamber of the execution mechanism is filled with oil, and the rod chamber is used for returning oil, so that the adduction action is realized.

During the operation of the arm, when the arm is in a negative load state, regeneration control of the oil is required to recover a part of the energy.

Specifically, an arm regeneration structure is arranged in the arm linkage 4, fig. 2 provides a specific structural form of the arm regeneration structure, the arm regeneration structure includes an arm regeneration oil path 43 and an arm regeneration valve 44, a one-way valve is arranged on the arm regeneration oil path 43, the arm regeneration oil path 43 is located between an oil return port T1 of the main valve core and an oil inlet P1 thereof, hydraulic oil can be enabled to flow from the oil return port T1 of the main valve core and the oil inlet P1 thereof, and the arm regeneration valve 44 is located on an oil path between the oil return port T1 of the valve core and the oil return path 102; further, an arm regeneration control valve 45 is connected to a control end of the arm regeneration valve 44. Wherein, in a preferred case, the arm regeneration valve 44 may be a pilot operated directional control valve, such as a two-position two-way directional control valve; the arm regeneration control valve 45 may be an electrically controlled directional valve, such as a two-position, three-way directional valve.

In the action process of the bucket rod, the bucket rod regeneration control valve 45 is controlled to be opened to a certain opening degree, a pressure signal of the pilot oil port Pp passes through the bucket rod regeneration control valve 45 and acts on the bucket rod regeneration valve 44 to enable the bucket rod regeneration valve 44 to be reversed, a damping hole is formed in the bucket rod regeneration valve 44, the damping of an oil path where oil returns from a main valve core of the bucket rod linkage 4 at the moment is increased, part of oil returns flows to an oil inlet P of the main valve core of the bucket rod linkage 4 through a one-way valve on the bucket rod regeneration oil path 43, and oil regeneration is achieved. At this time, the main valve core of the arm link 4 is in a right position function, the oil path between the oil inlet P of the oil inlet oil path 101 and the second arm link oil port a4 and the oil path between the first arm link oil port B4 and the oil return port T of the oil return path 102 are respectively communicated, so that part of oil corresponding to the rod chamber of the actuator flows to the rodless chamber, and the retraction is accelerated.

The working principle of the boom linkage 5 is substantially the same as that of the arm linkage 4, the boom linkage 5 includes a main valve core and a boom holding valve 51, the boom holding valve 51 may be disposed on an oil path between an oil port of the main valve core of the boom linkage 5 and a second boom linkage oil port a5 thereof, the second arm linkage oil port a5 is connected with a rodless cavity of a corresponding actuator, another oil port of the main valve core of the boom linkage 5 is connected with a first boom linkage oil port B5 thereof to control the corresponding actuator, an oil inlet P2 of the main valve core of the boom linkage 5 is connected with an oil inlet path 101, and an oil return port T2 of the main valve core of the boom linkage 5 is connected with an oil return path 102. Further, a boom holding pilot valve 52 is connected to a control chamber of the boom holding valve 51, and a control chamber of the boom holding pilot valve 52 is connected to a control oil passage at one end of the boom 5 when the main valve core is in the left position function.

Thus, when the arm does not operate, the main valve core of the boom linkage 5 is in a neutral position function, at this time, the oil paths among the oil inlet P of the oil inlet path 101, the oil return port T of the oil return path 102, the first boom linkage oil port B5, and the second boom linkage oil port a5 are cut off, and the boom holding valve 51 is in a closed state, so that the phenomenon of self-sinking due to leakage of oil in the rodless cavity of the boom cylinder to other places can be effectively prevented, the piston rod is kept in a current state without the action of other pressure oil, and the boom linkage 5 has a load holding function. In a preferred embodiment, the boom holding valve 51 may be a cartridge valve, and the boom holding pilot valve 52 may be a pilot operated directional control valve, such as a two-position two-way directional control valve.

When the movable arm descends, the main valve core of the movable arm linkage 5 is in a left position function, because the control oil path of the movable arm holding pilot valve 52 is communicated with the control oil path at the left end of the main valve core of the movable arm linkage 5, the movable arm holding pilot valve 52 is reversed under the action of a high-pressure signal, so that the movable arm holding valve 51 is opened reversely, and the oil path between the oil inlet P of the oil inlet path 101 and the first movable arm linkage oil port B5 and the oil path between the second movable arm linkage oil port a5 and the oil return port T of the oil return path 102 are respectively communicated; in order to accelerate the boom descending operation, a boom regeneration structure may be provided at the main valve core of the boom linkage 5, and fig. 3 provides another specific structural form of the arm regeneration structure, the arm regeneration structure may be a boom regeneration passage 53 provided in the main valve core, a check valve is installed on the boom regeneration passage 53, and a part of the oil returned from the second boom linkage oil port a5 flows to the first boom linkage oil port B5, even though a part of the oil corresponding to the rodless chamber of the actuator flows to the rod chamber thereof, thereby accelerating the boom descending operation.

It can be understood that the method for implementing the regeneration function related to the arm linkage 4 and the method for implementing the regeneration function related to the boom linkage 5 have equivalent functions, and the arm linkage 4 may also adopt the method for implementing the regeneration function related to the boom linkage 5, and an arm regeneration passage similar to the boom regeneration passage 53 in fig. 3 is provided in the main valve core of the arm linkage 4 to implement the regeneration function; similarly, the boom linkage 5 may also implement the regeneration function by providing a boom regeneration oil path similar to the arm regeneration oil path 43 in fig. 2, by using the method for implementing the regeneration function relating to the arm linkage 4, by providing a boom regeneration valve similar to the arm regeneration valve 44 in fig. 2 between the oil return port T2 of the main valve core of the boom linkage 5 and the oil return path 102, and by installing a check valve in the boom regeneration oil path, the hydraulic oil is caused to flow from the rodless chamber to the rod chamber of the corresponding cylinder, thereby implementing the regeneration function. In a specific embodiment, the arm linkage 4 and the boom linkage 5 of the multi-way valve according to the present invention may be selected as necessary to adopt a method for implementing the regeneration function related to the arm linkage 4 or a method for implementing the regeneration function related to the boom linkage 5.

When the movable arm ascends, the main valve core of the movable arm linkage 5 is in a right position function, a pressure signal of the pilot oil port Pp passes through the proportional control valve to push the main valve core to move, so that the main valve core is switched to the right position function, the movable arm retaining valve 51 is opened in the forward direction, an oil path between the oil inlet P of the oil inlet oil path 101 and the second movable arm oil coupling port a5 and an oil path between the first movable arm oil coupling port B5 and the oil return port T of the oil return path 102 are respectively communicated, oil is fed into a rodless cavity of the corresponding execution mechanism, oil is returned from a rod cavity of the corresponding execution mechanism, and the ascending action is realized.

In the embodiment, the header 1 includes a shutoff valve 11 and a control valve 12, and the control chamber of the shutoff valve 11 is connected to the pilot oil passage 100 through the control valve 12. When the executing mechanism does not act, the main valve cores of all the working couplings are in a neutral position function, the control valve 12 in the head coupling 1 is quickly reversed, so that a high-pressure signal of the pilot oil path 100 acts on the stop valve 11, the stop valve 11 is switched from a closed state to an open state, and oil input from the oil inlet P is directly unloaded. When the actuating mechanism acts, the stop valve 11 keeps a closed state, and oil input from the oil inlet P flows to the corresponding working connection. Wherein, the control valve 12 can be a solenoid proportional valve in a preferable case. In addition, an overflow valve can also be arranged in the first connection 1, and the overflow valve is positioned between the oil inlet oil way 101 and the oil return oil way 102 to limit the pressure of the system.

Although the multi-way valve according to the present invention is described in the above embodiments, the multi-way valve according to the present invention is not limited to the excavator, and the multi-way valve according to the present invention may be applied to other hydraulic machines. The proportional control valve is used for controlling the flow of the main valve core, a pressure compensation valve in the existing load sensing system is omitted, and a complex signal oil duct or an external signal pipeline does not need to be processed in the valve body, so that the processing and the assembly of the multi-way valve are more efficient, and the good speed regulation characteristic is ensured; the flow distribution precision of the control mode is high, and the structure is simple. The damping is arranged in the main valve core, the priority function is integrated in the main valve core of the working union, and each priority action sequence is determined by the position of the working union in the multi-way valve, so that the reasonable distribution of flow during the composite action is ensured, and the structure of the whole valve bank is simplified. The bucket rod is enabled to have a regeneration function by controlling the existence or nonexistence of the damping of an oil path where the bucket rod oil return cavity is located, and realizing the regeneration opening of the bucket rod under the working condition of negative load and the regeneration cutting-off of the bucket rod under the working condition of positive load and negative load.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. The multi-way valve is characterized by comprising a header (1), a plurality of working links arranged in sequence, a pilot oil way (100), an oil inlet oil way (101) for communicating the header (1) with each working link and an oil return oil way (102) for communicating the header (1) with each working link, wherein the working links comprise main valves, proportional control valves connected with the pilot oil way (100) are arranged at the control ends of the main valves, and priority oil ways are arranged in part of the main valves of the working links so as to increase the flow distributed by the working links and the working links arranged in front of the working links.

2. The multi-way valve according to claim 1, wherein each working link comprises a left walking link (2), a right walking link (3), an arm link (4), a movable arm link (5), a bucket link (6), a bulldozing link (7) and a slewing link (8) which are sequentially communicated with the oil inlet channel (101).

3. The multi-way valve according to claim 2, wherein the arm linkage (4) comprises a first arm linkage port (B4), a second arm linkage port (a4), an arm holding valve (41) and the main valve core, the main valve core comprises a first port (C1), a second port (C2) and an oil inlet (P1) connected with the oil inlet circuit (101), a third port (C3) connected with the first arm linkage port (B4), a fourth port (C4) connected with the second arm linkage port (a4) and an oil return port (T1) connected with the oil return circuit (102), and the arm holding valve (41) is located on the oil circuit between the third port (C3) of the main valve core and the first arm linkage port (B4).

4. The multi-way valve according to claim 3, characterized in that an arm holding pilot valve (42) is connected to the control chamber of the arm holding valve (41), and the control chamber of the arm holding pilot valve (42) is connected to the control oil path at one end of the main valve spool.

5. The multi-way valve of claim 3, wherein the arm linkage (4) further comprises an arm regeneration structure, and when the arm is in a negative load state, the arm regeneration structure enables the returned hydraulic oil to partially or completely flow from the rod cavity of the oil cylinder to the rodless cavity of the oil cylinder.

6. The multi-way valve according to claim 5, wherein the arm regeneration structure comprises an arm regeneration oil path (43) and an arm regeneration valve (44) between the return port (T1) of the main spool and the return oil path (102), the arm regeneration oil path (43) being between the return port (T1) of the main spool and the oil inlet (P1) thereof to enable hydraulic oil to flow from the rod chamber of the cylinder to the rodless chamber thereof.

7. The multiplex valve of claim 6, wherein the stick linkage (4) further comprises a stick regeneration control valve (45) connected to a control chamber of the stick regeneration valve (44).

8. The multiplex valve of claim 5 wherein said bucket rod regeneration structure includes a bucket rod regeneration passage disposed within said main spool.

9. The multiple-way valve according to claim 2, characterized in that the boom linkage (5) comprises the main spool and a boom-holding valve (51) on the oil path between the main spool and the cylinder.

10. The multi-way valve according to claim 9, characterized in that a boom holding pilot valve (52) is connected to the control chamber of the boom holding valve (51), and the control chamber of the boom holding pilot valve (52) is connected to the control oil path at one end of the main spool.

11. The multiplex valve of claim 9 wherein said boom linkage further includes a boom regeneration structure, said boom regeneration structure enabling return hydraulic oil to flow partially or entirely from the rodless chamber of the cylinder to the rod chamber thereof as the boom descends.

12. The multiplex valve as recited in claim 11, wherein said boom regeneration structure includes a boom regeneration circuit and is located between said main spool oil return port (T2) and said main spool oil inlet port (P2) to enable hydraulic oil to flow from said cylinder rodless chamber to said cylinder rod chamber.

13. The multiplex valve of claim 12 wherein said boom linkage further includes a boom regeneration control valve connected to a control chamber of said boom regeneration valve.

14. The multiplex valve of claim 11 wherein said boom regeneration structure includes a boom regeneration passage (53) disposed within said main spool.

15. The multi-way valve according to any one of claims 2 to 14, characterized in that the priority oil passages are provided on the main spool of the right walking linkage (3), the main spool of the arm linkage (4) and the main spool of the boom linkage (5).

16. The multiple-way valve according to claim 15, characterized in that a damping valve (9) is provided on the priority oil passage.

17. Multiple-way valve according to one of claims 1 to 14, characterized in that the lead-through (1) comprises a shut-off valve (11) and a control valve (12), the control chamber of the shut-off valve (11) being connected to the pilot oil circuit (100) via the control valve (12).

18. Excavator, characterized in that a multi-way valve according to any of claims 1-17 is provided.