阅读说明：本技术 一种基于改进型液压转向旁通优先阀的转向系统及方法 (Steering system and method based on improved hydraulic steering bypass priority valve ) 是由 徐峰 陈维雄 宋赛 靳祥强 王正航 于 2019-10-28 设计创作，主要内容包括：本公开公开了一种基于改进型液压转向旁通优先阀的转向系统和方法,改进型液压转向旁通优先阀包括,补偿阀的出油口端通过CF油口,连接单向阀A,进而与液压转向器的进油口相连,补偿阀的出油口端通过单向阀B与工作装置液压多路阀的恒流阀相连；补偿阀的出油口端通过单向阀B、EF油口与变量泵的进油口连接,优先阀的出油口端通过EF油口与工作装置液压多路阀的压力补偿器相连,LS溢流阀集成到液压转向旁通优先阀中,与液压转向器的LS口相连。改进型液压转向旁通优先阀中将补偿阀节流槽与优先节流槽分别独立于补偿阀与优先阀中,当匹配不同系统时无需重新设计或选型,提高了其通用性,降低了运营及维护成本,便于生产加工。(The improved hydraulic steering bypass priority valve comprises an oil outlet end of a compensation valve, a check valve A and a constant flow valve B, wherein the oil outlet end of the compensation valve is connected with an oil inlet of a hydraulic steering gear through a CF oil port; the oil outlet end of the compensating valve is connected with the oil inlet of the variable pump through an oil port of the one-way valve B, EF, the oil outlet end of the priority valve is connected with the pressure compensator of the hydraulic multi-way valve of the working device through an EF oil port, and the LS overflow valve is integrated into the hydraulic steering bypass priority valve and connected with the LS port of the hydraulic steering device. In the improved hydraulic steering bypass priority valve, the compensation valve throttling groove and the priority throttling groove are respectively independent of the compensation valve and the priority valve, redesign or model selection is not needed when different systems are matched, the universality is improved, the operation and maintenance cost is reduced, and the production and the processing are convenient.)

1. A steering system based on an improved hydraulic steering bypass priority valve is characterized in that: the hydraulic steering system comprises a variable pump, an improved hydraulic steering bypass priority valve, a hydraulic steering gear and a working device hydraulic multi-way valve;

the improved hydraulic steering bypass priority valve includes,

the oil outlet end of the compensating valve is connected with the one-way valve A through the CF oil port and is further connected with the oil inlet of the hydraulic steering gear,

the oil outlet end of the compensating valve is connected with a constant flow valve of a hydraulic multi-way valve of the working device through a one-way valve B;

the oil outlet end of the compensation valve is connected with the oil inlet of the variable displacement pump through the oil port of the one-way valve B, EF;

and the oil outlet end of the priority valve is connected with a pressure compensator of the hydraulic multi-way valve of the working device through an EF oil port.

2. A steering system based on an improved hydraulic steering bypass priority valve as claimed in claim 1 wherein the improved hydraulic steering bypass priority valve further comprises:

the oil inlet end of the compensating valve is connected with the oil outlet of the variable pump;

one end of the compensating valve with a spring is directly connected with the LS overflow valve;

and the LS overflow valve is integrated into the hydraulic steering bypass priority valve and is connected with an LS port of the hydraulic steering gear.

3. A steering system based on an improved hydraulic steering bypass priority valve as claimed in claim 1 wherein the improved hydraulic steering bypass priority valve further comprises:

one end of the priority valve with a spring passes through the CF oil port and is connected with the oil outlet end of the compensating valve;

the oil inlet end of the priority valve is connected with the oil outlet of the variable pump.

4. A steering system based on an improved hydraulic steering bypass priority valve as claimed in claim 1 wherein the hydraulic steering comprises:

the oil inlet end of the hydraulic steering gear is connected with the outlet of the one-way valve A, the CF oil port and the oil outlet end of the compensating valve;

the LS port of the hydraulic steering gear is connected with the LS overflow valve, and the LS port of the hydraulic steering gear is connected with the constant flow valve of the hydraulic multi-way valve of the working device through the one-way valve B.

5. A steering system based on an improved hydraulic steering bypass priority valve as claimed in claim 1 wherein the implement hydraulic multiplex valve comprises:

the hydraulic multi-way valve of the working device is a hydraulic multi-way valve of the working device with an LUDV pressure compensator, and one end of the LUDV pressure compensator, which is provided with a spring, is connected with an EF oil outlet and an oil outlet end of the priority valve.

6. A steering system based on an improved hydraulic steering bypass priority valve as claimed in claim 1 wherein the variable displacement pump comprises:

the oil outlet of the variable pump is respectively connected with the oil inlet end of the compensating valve, the oil inlet end of the priority valve and the oil inlet of the LUDV pressure compensator in the hydraulic multi-way valve of the working device;

the oil inlet of the variable pump is connected with the EF oil port, the outlet of the one-way valve B and the oil outlet end of the compensating valve.

7. A steering system based on an improved hydraulic steering bypass priority valve as claimed in claim 1,

the improved hydraulic steering bypass priority valve has the advantages that the compensation valve throttling groove and the priority throttling groove are respectively independent of the compensation valve and the priority valve, and the improved hydraulic steering bypass priority valve is installed by adopting a threaded cartridge valve.

8. A steering system based on an improved hydraulic steering bypass priority valve as claimed in claim 1,

and the matching relation between the compensation valve and the priority valve is optimized in a damping adjusting mode.

9. A steering method based on an improved hydraulic steering bypass priority valve is characterized by comprising the following steps,

in the initial rest position, the valve cores of the compensating valve and the priority valve in the improved hydraulic steering bypass priority valve are kept in a stop state by the aid of spring pre-tightening force, the opening from the variable pump to the hydraulic steering gear is fully opened, and the opening from the variable pump to the LUDV pressure compensator is in a throttling state, namely a closed state;

the variable pump is started, the hydraulic steering gear and the hydraulic multi-way valve of the working device do not act, the opening amplitude of the compensating valve is smaller than that in a normal working state, and the control oil way of the compensating valve always flows to enable the compensating valve to be in a dynamic state for standby; the pump is in a low-displacement state, and the flow rate only meets the leakage and the leakage of a constant flow valve of a hydraulic multi-way valve of a working device;

performing composite action, wherein the load pressure of the hydraulic multi-way valve of the working device is higher than that of the hydraulic steering gear; due to the pre-valve compensation characteristic of the improved hydraulic steering bypass priority valve, the hydraulic steering gear is in a priority state no matter whether the flow is saturated or not;

performing compound action, wherein the load pressure of the hydraulic multi-way valve of the working device is lower than that of the hydraulic steering gear; when the flow is saturated, namely the required flow is greater than the flow provided by the variable pump, the pressure of an EF oil port of the priority valve acts on an LUDV pressure compensator of a hydraulic multi-way valve of the working device, and the LUDV pressure compensator is reduced, so that more oil enters a hydraulic steering gear to realize steering priority;

the priority valve detects the front and back pressure difference of the compensating valve, and introduces the pressure oil at the outlet of the variable pump into the multi-way valve Ls to control the oil way to close the compensating valve, so that the oil flows into the steering system.

Technical Field

The disclosure relates to the technical field of loaders, in particular to a steering system and a steering method based on an improved hydraulic steering bypass priority valve.

Background

The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.

The higher requirements on the control complexity and the low power consumption in the existing wheel type engineering machinery, particularly the wheel type loader, are provided, so that the combined application of the LUDV hydraulic system with the flow saturation resistance function and the hydraulic steering bypass priority valve can have wide application space. In the design of the prior hydraulic steering bypass priority valve, a compensation valve throttling groove and a priority throttling groove are mostly designed on the same valve rod and integrated on a valve core of the bypass priority valve, so that the structure is complex, the cost is increased, the production and the processing are inconvenient, the sizes of the two throttling grooves need to be redesigned and adjusted to adapt to load changes in the application of different engineering mechanical products, and the generalization cannot be realized; because the matching relation exists between the compensation valve throttling groove and the priority throttling groove, when different systems are matched, the valve core throttling groove needs to be redesigned, the universality is reduced, and the operation and maintenance cost is increased; because the compensation valve throttling groove and the priority throttling groove share the same spring, the performance of the bypass priority valve is seriously influenced when the rigidity of the spring is weakened in the using process; the steering gear is provided with an Ls overflow valve; because the steering gear has compact structure and limited space, the Ls overflow valve increases the design and processing difficulty, the failure rate and the maintenance difficulty; the Ls one-way valve is independent, leakage points and pipeline configuration are increased, and the possibility of reverse oil port installation exists; the control valve rod directly contacts with the valve body, the risk of scratching the valve body and the valve rod exists when the oil liquid cleanliness is not enough, and the difficulty of repairing after scratching is large.

Disclosure of Invention

In order to solve the problems, the present disclosure provides a steering system and a method based on an improved hydraulic steering bypass priority valve, in the improved hydraulic steering bypass priority valve, a compensation valve throttling groove and a priority throttling groove are respectively independent of the compensation valve and the priority valve, when different systems are matched, redesign or model selection is not needed, the universality is improved, the operation and maintenance cost is reduced, and the production and processing are convenient.

In order to achieve the purpose, the following technical scheme is adopted in the disclosure:

the present disclosure provides a steering system based on an improved hydraulic steering bypass priority valve, which comprises a variable pump, an improved hydraulic steering bypass priority valve, a hydraulic steering gear and a working device hydraulic multi-way valve;

the improved hydraulic steering bypass priority valve includes,

the oil outlet end of the compensating valve is connected with the one-way valve A through the CF oil port and is further connected with the oil inlet of the hydraulic steering gear,

the oil outlet end of the compensating valve is connected with a constant flow valve of a hydraulic multi-way valve of the working device through a one-way valve B;

the oil outlet end of the compensation valve is connected with the oil inlet of the variable displacement pump through the oil port of the one-way valve B, EF;

and the oil outlet end of the priority valve is connected with a pressure compensator of the hydraulic multi-way valve of the working device through an EF oil port.

Further, the improved hydraulic steering bypass priority valve further comprises:

the oil inlet end of the compensating valve is connected with the oil outlet of the variable pump;

one end of the compensating valve with a spring is directly connected with the LS overflow valve;

and the LS overflow valve is integrated into the hydraulic steering bypass priority valve and is connected with an LS port of the hydraulic steering gear.

Further, the improved hydraulic steering bypass priority valve further comprises:

one end of the priority valve with a spring passes through the CF oil port and is connected with the oil outlet end of the compensating valve;

the oil inlet end of the priority valve is connected with the oil outlet of the variable pump.

Further, the hydraulic steering gear includes:

the oil inlet end of the hydraulic steering gear is connected with the outlet of the one-way valve A, the CF oil port and the oil outlet end of the compensating valve;

the LS port of the hydraulic steering gear is connected with the LS overflow valve, and the LS port of the hydraulic steering gear is connected with the constant flow valve of the hydraulic multi-way valve of the working device through the one-way valve B.

Further, the working device hydraulic multi-way valve includes:

the hydraulic multi-way valve of the working device is a hydraulic multi-way valve of the working device with an LUDV pressure compensator, and one end of the LUDV pressure compensator, which is provided with a spring, is connected with an EF oil outlet and an oil outlet end of the priority valve.

Further, the variable displacement pump includes:

the oil outlet of the variable pump is respectively connected with the oil inlet end of the compensating valve, the oil inlet end of the priority valve and the oil inlet of the LUDV pressure compensator in the hydraulic multi-way valve of the working device;

the oil inlet of the variable pump is connected with the EF oil port, the outlet of the one-way valve B and the oil outlet end of the compensating valve.

Furthermore, the improved hydraulic steering bypass priority valve has the advantages that the compensation valve throttling groove and the priority throttling groove are respectively independent from the compensation valve and the priority valve, and the improved hydraulic steering bypass priority valve is installed by adopting a threaded cartridge valve.

Furthermore, the matching relation between the compensation valve and the priority valve is optimized in a damping adjusting mode.

The present disclosure provides a steering method based on an improved hydraulic steering bypass priority valve, comprising,

in the initial rest position, the valve cores of the compensating valve and the priority valve in the improved hydraulic steering bypass priority valve are kept in a stop state by the aid of spring pre-tightening force, the opening from the variable pump to the hydraulic steering gear is fully opened, and the opening from the variable pump to the LUDV pressure compensator is in a throttling state, namely a closed state;

the variable pump is started, the hydraulic steering gear and the hydraulic multi-way valve of the working device do not act, the opening amplitude of the compensating valve is smaller than that in a normal working state, and the control oil way of the compensating valve always flows to enable the compensating valve to be in a dynamic state for standby; the pump is in a low-displacement state, and the flow rate only meets the leakage and the leakage of a constant flow valve of a hydraulic multi-way valve of a working device;

performing composite action, wherein the load pressure of the hydraulic multi-way valve of the working device is higher than that of the hydraulic steering gear; due to the pre-valve compensation characteristic of the improved hydraulic steering bypass priority valve, the hydraulic steering gear is in a priority state no matter whether the flow is saturated or not;

performing compound action, wherein the load pressure of the hydraulic multi-way valve of the working device is lower than that of the hydraulic steering gear; when the flow is saturated, namely the required flow is greater than the flow provided by the variable pump, the pressure of an EF oil port of the priority valve acts on an LUDV pressure compensator of a hydraulic multi-way valve of the working device, and the LUDV pressure compensator is reduced, so that more oil enters a hydraulic steering gear to realize steering priority;

the priority valve detects the front and back pressure difference of the compensating valve, and introduces the pressure oil at the outlet of the variable pump into the multi-way valve Ls to control the oil way to close the compensating valve, so that the oil flows into the steering system.

Compared with the prior art, the beneficial effect of this disclosure is:

1. in the improved hydraulic steering bypass priority valve, the compensation valve throttling groove and the priority throttling groove are respectively independent of the compensation valve and the priority valve, so that the structural form is simplified, the cost is reduced, and the production and the processing are convenient;

2. by adjusting the matching relation between the damping optimization compensation valve and the priority valve, the universality is improved, and the operation and maintenance cost is reduced;

3. because the springs of the compensation valve and the priority valve are independent and adjustable, when the rigidity of the springs is weakened in the using process, the correlation influence can not occur, and the springs can be optimized by adjusting the spring force;

4. an Ls overflow valve is not required to be installed in the hydraulic steering gear, so that the structure of the hydraulic steering gear is simplified, and the design and processing difficulty, the failure rate and the maintenance difficulty are reduced;

5, the Ls overflow valve is integrated into the improved hydraulic steering bypass priority valve, so that leakage points and pipeline configuration are reduced, misassembly is avoided, and later maintenance cost is reduced;

6. the threaded cartridge valve is not in direct contact with the valve body, the pollution resistance is high, the risk of scratching is avoided when the oil cleanliness is not enough, and the maintenance is avoided.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure and are not to limit the disclosure.

FIG. 1 is a schematic view of a prior art hydraulic steering system;

FIG. 2 is a schematic diagram of a steering system based on an improved hydraulic steering bypass priority valve of the present disclosure.

Wherein, 1, variable pump; 2. an improved hydraulic steering bypass priority valve; 3. a hydraulic steering gear; 4. a working device hydraulic multi-way valve; 5. a compensation valve; 6. an oil inlet of the hydraulic steering gear; 7. an LS overflow valve; 8. a constant flow valve; 9. a priority valve; 10. a LUDV pressure compensator; 11. a one-way valve A; 12. a check valve B; the broken line indicates the control oil passage, and the solid line indicates the main oil passage.

The specific implementation mode is as follows:

the present disclosure is further described with reference to the following drawings and examples.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

As shown in fig. 2, the present disclosure provides a steering system based on an improved hydraulic steering bypass priority valve, which comprises a variable displacement pump 1, an improved hydraulic steering bypass priority valve 2, a hydraulic steering gear 3 and a working device hydraulic multi-way valve 4;

the improved hydraulic steering bypass priority valve 2 includes,

the oil outlet end of the compensating valve 5 is connected with the one-way valve A through a CF oil port and is further connected with the oil inlet 6 of the hydraulic steering gear,

the oil outlet end of the compensating valve 5 is connected with the oil inlet of the variable displacement pump 1 through the oil port of the one-way valve B, EF;

the oil outlet end of the compensating valve 5 is connected with a constant flow valve 8 of the hydraulic multi-way valve 4 of the working device through a one-way valve B;

the oil inlet end of the compensating valve 5 is connected with the oil outlet P of the variable pump 1;

one end of the compensating valve 5 with a spring is directly connected with the LS overflow valve 7;

the LS overflow valve 7 is integrated into the hydraulic steering bypass priority valve 2 and is connected with an LS port of the hydraulic steering gear 3;

further preferably, an oil outlet end of the priority valve 9 is connected with a pressure compensator 10 of the hydraulic multi-way valve 4 of the working device through an EF oil port;

one end of the priority valve 9 with a spring is connected with the oil outlet end of the compensating valve 5 through a CF oil port;

the oil inlet end of the priority valve 9 is connected with the oil outlet P of the variable displacement pump 1.

Further preferably, the oil inlet end of the hydraulic steering gear 3 is connected with the outlet of the check valve a, the CF oil port and the oil outlet end of the compensating valve 5;

an LS port of the hydraulic steering gear 3 is connected with an LS overflow valve 7; and the LS port of the hydraulic steering gear 3 is connected with a constant flow valve 8 of the hydraulic multi-way valve 4 of the working device through a one-way valve B.

Further preferably, the working device hydraulic multi-way valve 4 is a working device hydraulic multi-way valve with an LUDV pressure compensator, and one end of the LUDV pressure compensator 10 with a spring is connected with an EF oil outlet and an oil outlet end of the priority valve 9;

further preferably, an oil outlet P of the variable displacement pump 1 is respectively connected with an oil inlet end of the compensating valve 5, an oil inlet end of the priority valve 9 and an oil inlet of the LUDV pressure compensator 10 in the hydraulic multi-way valve 4 of the working device; the oil inlet of the variable pump 1 is connected with the EF oil port, the outlet of the one-way valve B and the oil outlet end of the compensating valve 5.

The variable pump, the hydraulic steering gear and other structures which are not referred to in the disclosure in the hydraulic multi-way valve of the working device all adopt the composition structures in the prior art.

The LS overflow valve is an overflow valve added at the LS opening, and the LS is a load sensitive opening for acquiring a pressure signal from the hydraulic steering gear;

the overflow valve is added at the LS mouth, so that the situation that when the hydraulic steering gear is driven to the bottom, the pressure of the CF oil port and the LS oil port reaches balance, the priority valve cannot be reversed, the EF mouth does not have oil to flow away, the system is suppressed, the heating noise is generated, and even the variable displacement pump is damaged.

The CF oil port is a priority flow oil port which preferentially supplies oil to the steering gear; the EF oil port is a bypass oil port, and when the redirector does not need oil or too much oil output by the pump can not be used by the redirector, the oil is conveyed to a second-stage working mechanism, such as a multi-way valve, through the EF oil port.

Further preferably, the improved hydraulic steering bypass priority valve has the advantages that the throttling groove of the compensating valve and the throttling groove of the priority valve are respectively independent of the compensating valve and the priority valve, and a threaded cartridge valve mode is adopted, so that the structural form is simplified, the cost is reduced, and the production and the processing are convenient;

the threaded cartridge valve is not in direct contact with the valve body, so that the risk of scratching is avoided when the oil cleanliness is insufficient, and the maintenance is avoided;

by adjusting the matching relation between the damping optimization compensation valve and the priority valve, redesign or model selection is not needed when different systems are matched, the universality is improved, and the operation and maintenance cost is reduced.

The present disclosure provides a steering method based on an improved hydraulic steering bypass priority valve, comprising,

(1) an initial rest position; in the initial rest position, the spools of the compensation valve and the priority valve in the improved hydraulic steering bypass priority valve are kept in a stopped state by spring preload, the opening from the variable pump to the hydraulic steering gear is fully opened (P → CF), and the opening from the variable pump to the LUDV pressure compensator is throttled, i.e., closed (P → EF);

(2) the variable pump is started, the hydraulic steering gear and the hydraulic multi-way valve of the working device do not act, the opening amplitude of the compensating valve is small, and the control oil way of the compensating valve always flows to enable the compensating valve to be in a dynamic state for standby; the pump is in a low-displacement state, and the flow rate only meets the leakage and the leakage of a constant flow valve of a hydraulic multi-way valve of a working device;

(3) performing composite action, wherein the load pressure of the hydraulic multi-way valve of the working device is higher than that of the hydraulic steering gear; due to the pre-valve compensation characteristic of the improved hydraulic steering bypass priority valve, the hydraulic steering gear is in a priority state no matter whether the flow is saturated or not;

(4) performing compound action, wherein the load pressure of the hydraulic multi-way valve of the working device is lower than that of the hydraulic steering gear; when the flow is saturated, namely the required flow is greater than the flow provided by the variable pump, the pressure of an EF oil port of the priority valve acts on an LUDV pressure compensator of a hydraulic multi-way valve of the working device, and the LUDV pressure compensator is reduced, so that more oil enters a hydraulic steering gear to realize steering priority;

the priority valve detects the front and back pressure difference of the compensating valve, and introduces the pressure oil at the outlet of the variable pump into the multi-way valve Ls to control the oil way to close the compensating valve, so that the oil flows into the steering system.

In one or more embodiments, when the hydraulic steering gear works, the flow process of the main oil circuit and the control oil circuit is as follows:

oil flows into the oil inlet end of the hydraulic steering gear through the oil outlet P of the variable pump and the compensating valve 5 through the CF oil port, the oil flows in the hydraulic steering gear, and the hydraulic steering gear works;

meanwhile, in the control oil circuit, oil flows back to the improved hydraulic steering bypass priority valve through the LS port and flows to a constant flow valve of a hydraulic multi-way valve of the working device through the one-way valve B; part of the oil can also directly flow back to the variable displacement pump.

In one or more embodiments, when the working device hydraulic multi-way valve works, the flow process of the main oil path and the control oil path is as follows:

the oil directly flows into the hydraulic multi-way valve of the working device through the oil outlet P of the variable pump, meanwhile, in the control oil path, a part of the oil directly flows back into the variable pump, and a part of the oil is leaked through the constant flow valve.

The above is merely a preferred embodiment of the present disclosure and is not intended to limit the present disclosure, which may be variously modified and varied by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.

Although the present disclosure has been described with reference to specific embodiments, it should be understood that the scope of the present disclosure is not limited thereto, and those skilled in the art will appreciate that various modifications and changes can be made without departing from the spirit and scope of the present disclosure.