阅读说明：本技术 油源控制阀组、先导控制系统以及液压油处理方法 (Oil source control valve group, pilot control system and hydraulic oil processing method ) 是由 李文举 张磊 吴清本 杨正维 宫永辉 于 2021-07-01 设计创作，主要内容包括：本发明提供一种油源控制阀组,包括：阀体,具有回油口T以及连通的进油口P和出油口Pr,进油口P和出油口Pr连通的通路上依次设置有减压溢流单元、过滤器和第一换向阀；减压溢流单元的进油口与进油口P导通,减压溢流单元的出油口与过滤器的进油口连通并在通路,减压溢流单元的卸油口与回油口T导通；第一换向阀的进油口与过滤器的出油口连通,第一换向阀的第一出油口与出油口Pr导通；过滤器设置在减压溢流单元的出油口与第一换向阀的进油口之间。本发明还提供一种先导控制系统以及液压油处理方法。本发明提供的油源控制阀组、先导控制系统和液压油处理方法避免流经第一换向阀的液压油中的杂质堵塞第一换向阀的阀芯,减少第一换向阀的故障率。(The invention provides an oil source control valve group, comprising: the valve body is provided with an oil return port T and an oil inlet P and an oil outlet Pr which are communicated, and a pressure reduction overflow unit, a filter and a first reversing valve are sequentially arranged on a passage through which the oil inlet P and the oil outlet Pr are communicated; an oil inlet of the pressure reduction overflow unit is communicated with the oil inlet P, an oil outlet of the pressure reduction overflow unit is communicated with an oil inlet of the filter and is in a passage, and an oil discharge port of the pressure reduction overflow unit is communicated with an oil return port T; an oil inlet of the first reversing valve is communicated with an oil outlet of the filter, and a first oil outlet of the first reversing valve is communicated with an oil outlet Pr; the filter is arranged between an oil outlet of the pressure reduction overflow unit and an oil inlet of the first reversing valve. The invention also provides a pilot control system and a hydraulic oil processing method. The oil source control valve group, the pilot control system and the hydraulic oil processing method provided by the invention can be used for preventing impurities in the hydraulic oil flowing through the first reversing valve from blocking the valve core of the first reversing valve and reducing the fault rate of the first reversing valve.)

1. An oil source control valve group is characterized in that the oil source control valve group is arranged on the oil inlet side of a pilot valve (9); this oil source control valve group includes: the valve body (200) is provided with an oil return port T and an oil inlet P and an oil outlet Pr which are communicated, and a pressure reduction overflow unit (100), a filter (6) and a first reversing valve (5) are sequentially arranged on a passage where the oil inlet P is communicated with the oil outlet Pr;

an oil inlet of the pressure reduction overflow unit (100) is communicated with an oil inlet P of the valve body (200), an oil outlet of the pressure reduction overflow unit (100) is communicated with an oil inlet of the filter (6), and an oil outlet of the pressure reduction overflow unit (100) is communicated with an oil return port T of the valve body (200);

an oil inlet of the first reversing valve (5) is communicated with an oil outlet of the filter (6), a first oil outlet of the first reversing valve (5) is communicated with an oil outlet Pr of the valve body (200), and an oil outlet Pr of the valve body (200) is communicated with an oil inlet of the pilot valve (9);

the filter (6) is arranged between an oil outlet of the pressure reduction overflow unit (100) and an oil inlet of the first reversing valve (5).

2. The oil source control valve group according to claim 1, wherein the valve body (200) is further provided with a first communicating port Bv1 and a second communicating port Pv which are communicated, the first communicating port Bv1 is communicated with an oil outlet of the pressure reduction overflow unit (100), the second communicating port Pv is communicated with an oil inlet of the first reversing valve (5), and the filter (6) is arranged on a channel through which the first communicating port Bv1 is communicated with the second communicating port Pv.

3. The set of source control valves according to claim 2, wherein the relief and overflow unit (100) comprises: a pressure reducing valve (1) and an overflow valve (2);

the oil inlet of the pressure reducing valve (1) is communicated with the oil inlet P of the valve body (200), the oil outlet of the pressure reducing valve (1) is communicated with the oil inlet of the overflow valve (2), and the oil outlet of the overflow valve (2) and the oil outlet of the pressure reducing valve (1) are communicated with the oil return port T of the valve body (200).

4. The set of source control valves of claim 3, further comprising: an oil inlet of the one-way valve (3) is communicated with an oil outlet of the pressure reducing valve (1), and an oil outlet of the one-way valve (3) is communicated with the first communication port Bv 1.

5. The set of source control valves of claim 4, further comprising: the energy accumulator (4), the energy accumulator (4) with the oil-out intercommunication of check valve (3).

6. The set of oil source control valves according to claim 1, characterized in that the first change valve (5) is a two-position three-way solenoid valve; and a second oil outlet of the first reversing valve (5) is communicated with an oil return port T of the valve body (200).

7. The valve group of oil source control according to claim 1, characterized in that a filtering one-way valve (8) is connected in parallel between the oil inlet and the oil outlet of the filter (6).

8. The set of source control valves of claim 2, further comprising: the oil inlet of each second reversing valve (7) is communicated with the second communication port Pv, the first oil outlet of each second reversing valve (7) is communicated with the oil return port T of the valve body (200), and the second oil outlet of each second reversing valve (7) is communicated with the control oil port of the hydraulic actuating mechanism.

9. Valve group according to claim 8, characterized in that the second reversal valve (7) is a two-position three-way solenoid valve.

10. A pilot control system, characterized by comprising a hydraulic pump (11), a pilot valve (9), a main control valve (12), at least one set of hydraulic actuators and a set of oil source control valves according to any one of claims 1-9; the hydraulic pump (11) is used for conveying hydraulic oil to the pilot valve (9) and the hydraulic actuating mechanism, the pilot valve (9) is communicated with the main control valve (12), the pilot valve (9) is used for controlling the opening degree of a valve element of the main control valve (12), the main control valve (12) is installed between the hydraulic pump (11) and the hydraulic actuating mechanism and used for controlling connection or disconnection between the hydraulic pump (11) and the hydraulic actuating mechanism, and the oil source control valve group is installed on the oil inlet side of the pilot valve (9).

11. The pilot control system according to claim 10, wherein the oil inlet P of the valve body (200) is externally connected to a hydraulic pump (11) or communicated with an oil inlet of the main control valve (12).

12. A hydraulic oil processing method applies an oil source control valve group to process hydraulic oil, the oil source control valve group is installed on the oil inlet side of a pilot valve (9), and the oil source control valve group is characterized by comprising the following steps: the valve body (200) is provided with an oil return port T and an oil inlet P and an oil outlet Pr which are communicated, a pressure reduction overflow unit (100), a filter (6) and a first reversing valve (5) are sequentially arranged on a passage communicated with the oil outlet Pr, the oil inlet of the pressure reduction overflow unit (100) is communicated with the oil inlet P of the valve body (200), the filter (6) is arranged between the oil outlet of the pressure reduction overflow unit (100) and the oil inlet of the first reversing valve (5), the first oil outlet of the first reversing valve (5) is communicated with the oil outlet Pr of the valve body (200), and the processing method comprises the following steps:

hydraulic oil enters from an oil inlet P of a valve body (200) of the oil source control valve group and is subjected to pressure reduction treatment through a pressure reduction overflow unit (100) of the oil source control valve group;

the hydraulic oil after pressure reduction is filtered by a filter (6) of the oil source control valve group;

and the decompressed and filtered hydraulic oil enters the pilot valve (9) through a first reversing valve (5) of the oil source control valve group.

Technical Field

The invention relates to the technical field of hydraulic control, in particular to an oil source control valve group, a pilot control system and a hydraulic oil processing method.

Background

Engineering machinery such as an excavator works in a severe environment with high temperature, high humidity and large dust for a long time, however, the requirement of hydraulic elements in the engineering machinery on the cleanliness of hydraulic oil is high, and some tiny particles in the hydraulic oil may cause the response speed of the hydraulic elements to lag or fail, thereby affecting the working performance of the whole engineering machinery.

In a pilot system of a construction machine such as a mini excavator, hydraulic oil supplied to a pilot valve is generally converted into qualified hydraulic oil by a pilot oil source valve and then supplied to the pilot valve, and in order to ensure the cleanliness of the hydraulic oil supplied to the pilot valve, a filter device is added to the pilot oil source valve to filter the hydraulic oil. In the prior art, the filter device is arranged in a pilot oil source valve in two ways: front-loading and rear-loading. In the front-mounted type, because the hydraulic oil is not processed by the pilot oil source valve, the oil pressure is high, the size of the filtering device is large, and because the pressure of the hydraulic oil is high, the high-pressure hydraulic oil impacts a filter element of the filtering device for a long time, and the filtering device is easy to break down; in the post-type hydraulic oil, the hydraulic oil firstly passes through the pilot oil source valve and then is filtered by the filtering device, so that the hydraulic oil passing through the control valve in the pilot oil source valve is not filtered, and the valve core of the control valve is easily blocked.

Therefore, a need exists for an apparatus to address at least one of the above-mentioned problems.

Disclosure of Invention

The invention aims to provide an oil source control valve group, a pilot control system and a hydraulic oil processing method, and aims to solve the problems of clamping stagnation, low response speed and the like caused by blockage of a valve core of a control valve in a pilot oil source valve due to the arrangement mode of a filter device in the pilot oil source valve in the prior art.

In order to achieve the above object, a first aspect of the present invention provides an oil supply control valve group, which is installed on an oil inlet side of a pilot valve; this oil source control valve group includes: the valve body is provided with an oil return port T and an oil inlet P and an oil outlet Pr which are communicated, and a passage through which the oil inlet P is communicated with the oil outlet Pr is sequentially provided with a pressure reduction overflow unit, a filter and a first reversing valve; an oil inlet of the pressure reduction overflow unit is communicated with an oil inlet P of the valve body, an oil outlet of the pressure reduction overflow unit is communicated with an oil inlet of the filter, and an oil discharge port of the pressure reduction overflow unit is communicated with an oil return port T of the valve body; an oil inlet of the first reversing valve is communicated with an oil outlet of the filter, a first oil outlet of the first reversing valve is communicated with an oil outlet Pr of the valve body, and the oil outlet Pr of the valve body is communicated with an oil inlet of the pilot valve; the filter is arranged between an oil outlet of the pressure reduction overflow unit and an oil inlet of the first reversing valve.

Specifically, the valve body is further provided with a first communicating port Bv1 and a second communicating port Pv which are communicated, the first communicating port Bv1 is communicated with an oil outlet of the pressure reduction overflow unit, the second communicating port Pv is communicated with an oil inlet of the first reversing valve, and the filter is arranged on a passage through which the first communicating port Bv1 is communicated with the second communicating port Pv.

Specifically, the decompression overflow unit comprises: a pressure reducing valve and an overflow valve; the oil inlet of the pressure reducing valve is communicated with the oil inlet P of the valve body, the oil outlet of the pressure reducing valve is communicated with the oil inlet of the overflow valve, and the oil outlet of the overflow valve and the oil discharging port of the pressure reducing valve are communicated with the oil return port T of the valve body.

Specifically, the oil source control valve group further comprises: an oil inlet of the one-way valve is communicated with an oil outlet of the pressure reducing valve, and an oil outlet of the one-way valve is communicated with the first communication port Bv 1.

Specifically, the oil source control valve group further comprises: and the energy accumulator is communicated with the oil outlet of the one-way valve.

Specifically, the first reversing valve is a two-position three-way electromagnetic valve; and the second oil outlet of the first reversing valve is communicated with the oil return port T of the valve body.

Specifically, a filtering one-way valve is connected in parallel between an oil inlet and an oil outlet of the filter.

Specifically, the oil source control valve group further comprises: and the oil inlet of each second reversing valve is communicated with the second communication port Pv, the first oil outlet of each second reversing valve is communicated with the oil return port T of the valve body, and the second oil outlet of each second reversing valve is communicated with the control oil port of the hydraulic actuating mechanism.

Specifically, the second reversing valve is a two-position three-way electromagnetic valve.

In another aspect of the present invention, a pilot control system is provided, which includes a hydraulic pump, a pilot valve, a main control valve, at least one set of hydraulic actuators, and the above-mentioned oil source control valve set; the hydraulic pump is used for conveying hydraulic oil to the pilot valve and the hydraulic actuating mechanism, the pilot valve is communicated with the main control valve, the pilot valve is used for controlling the opening degree of a valve core of the main control valve, the main control valve is installed between the hydraulic pump and the hydraulic actuating mechanism and used for controlling the connection or disconnection between the hydraulic pump and the hydraulic actuating mechanism, and the oil source control valve group is installed on the oil inlet side of the pilot valve.

Specifically, an oil inlet P of the valve body is externally connected with a hydraulic pump or is communicated with an oil inlet of the main control valve.

In another aspect of the present invention, a method for processing hydraulic oil is provided, in which an oil source control valve set is used to process hydraulic oil, the oil source control valve set is installed at an oil inlet side of a pilot valve, and the oil source control valve set includes: the valve body is provided with an oil return port T and an oil inlet P and an oil outlet Pr which are communicated, a pressure reduction overflow unit, a filter and a first reversing valve are sequentially arranged on a passage communicated with the oil outlet Pr from the oil inlet P, the oil inlet of the pressure reduction overflow unit is communicated with the oil inlet P of the valve body, the filter is arranged between the oil outlet of the pressure reduction overflow unit and the oil inlet of the first reversing valve, the first oil outlet of the first reversing valve is communicated with the oil outlet Pr of the valve body, and the processing method comprises the following steps: hydraulic oil enters from an oil inlet P of a valve body of the oil source control valve group and is subjected to pressure reduction treatment through a pressure reduction overflow unit of the oil source control valve group; filtering the hydraulic oil subjected to pressure reduction treatment by a filter of the oil source control valve group; and the hydraulic oil after being subjected to pressure reduction and filtration enters the pilot valve through a first reversing valve of the oil source control valve group.

According to the oil source control valve group provided by the invention, the pressure reduction overflow unit is adopted to carry out pressure reduction treatment on the hydraulic oil entering from the oil inlet P, the hydraulic oil after pressure reduction treatment enters the filter, impurities in the hydraulic oil are filtered through the filter, the cleanliness of the hydraulic oil flowing through the first reversing valve is ensured, the problems of clamping stagnation, low response speed and the like caused by valve core blockage of the first reversing valve are avoided, thus the hydraulic oil flowing from the oil outlet of the first reversing valve into the pilot valve is clean after passing through the oil outlet Pr, the use safety of the pilot valve is ensured after the pressure reduction and filtration treatment of the hydraulic oil, and the normal work of the pilot valve is ensured.

The oil source control valve group, the pilot control system and the hydraulic oil processing method provided by the invention solve the problems of jamming of the first reversing valve and low response speed caused by blocking of impurities in the hydraulic oil flowing through the first reversing valve on the valve core of the first reversing valve, reduce the failure rate of the first reversing valve, reduce the pressure of the hydraulic oil flowing through the filter through the pressure reduction overflow unit, and simultaneously avoid the defects of large size and heavy structure of the filter when the high-pressure hydraulic oil is processed.

Additional features and advantages of embodiments 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 embodiments 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 embodiments of the invention without limiting the embodiments of the invention. In the drawings:

FIG. 1 is a schematic structural diagram of an oil source control valve assembly provided by the present invention;

fig. 2 is a schematic diagram of a pilot control system according to the present invention.

Description of the reference numerals

1 pressure reducing valve and 2 overflow valve

3 one-way valve 4 energy accumulator

5 first reversing valve 6 filter

7 second reversing valve 8 filtering one-way valve

9 pilot valve 11 hydraulic pump

12 main control valve 13 walking motor

14 hydraulic cylinder 131 motor body

132 motor variable displacement mechanism 100 relief overflow unit

200 valve body

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 embodiments of the present invention, unless otherwise specified, the use of directional terms such as "upper, lower, top, and bottom" is generally used with respect to the orientation shown in the drawings or the positional relationship of the components with respect to each other in the vertical, or gravitational direction.

In a first aspect of the present invention, an oil source control valve assembly is provided, fig. 1 is a schematic structural diagram of the oil source control valve assembly, as shown in fig. 1, the oil source control valve assembly is installed on an oil inlet side of a pilot valve 9; this oil source control valve group includes: the valve body 200 is provided with an oil return port T and an oil inlet P and an oil outlet Pr which are communicated, and a passage of the oil inlet P communicated with the oil outlet Pr is sequentially provided with a pressure reduction overflow unit 100, a filter 6 and a first reversing valve 5; an oil inlet of the pressure reduction overflow unit 100 is communicated with the oil inlet P, an oil outlet of the pressure reduction overflow unit 100 is communicated with an oil inlet of the filter 6, and an oil outlet of the pressure reduction overflow unit 100 is communicated with an oil return port T of the valve body 200; an oil inlet of the first reversing valve 5 is communicated with an oil outlet of the filter 6, a first oil outlet of the first reversing valve 5 is communicated with an oil outlet Pr of the valve body 200, and an oil outlet Pr of the valve body 200 is communicated with an oil inlet of the pilot valve 9; the filter 6 is arranged between an oil outlet of the pressure reduction overflow unit 100 and an oil inlet of the first reversing valve 5.

The invention provides an oil source control valve group, which is arranged at the oil inlet side of a pilot valve 9 and is used for adjusting hydraulic oil conveyed to the pilot valve 9 by a hydraulic pump 11, the clean, safe and reliable hydraulic oil is provided for the pilot valve 9 through the oil source control valve group so as to enable the pilot valve 9 to work normally, an oil inlet P, an oil outlet Pr and an oil return port T are arranged on a valve body 200, the hydraulic oil pumped by the hydraulic pump 11 enters a decompression overflow unit 100 from the oil inlet P of the valve body 200, the hydraulic pump 11 is a constant displacement pump or a variable displacement pump, the oil return port T is externally connected with an oil tank, in order to prolong the service life of each component in the oil source control valve group, the hydraulic pump 11 pumps the hydraulic oil from the oil inlet P to the decompression overflow unit 100 for decompression treatment, then the hydraulic oil after the decompression treatment enters a filter 6 through the oil outlet of the decompression overflow unit 100, impurities in the hydraulic oil are filtered through the filter 6, filtered hydraulic oil flows out of the oil outlet Pr through the first reversing valve 5, the oil outlet Pr is externally connected with the pilot valve 9, the first reversing valve 5 is used for controlling the on-off of an oil path of the hydraulic oil conveyed to the pilot valve 9, the hydraulic oil flowing through the first reversing valve 5 is filtered by the filter 6, the situation that the valve core of the first reversing valve 5 is blocked by impurities in the hydraulic oil can be avoided, the problems that the first reversing valve 5 is blocked, the response speed is slow and the like due to the blockage of the valve core of the first reversing valve 5 are avoided, the fault rate of the first reversing valve 5 is reduced, and the hydraulic oil is conveyed to the pilot valve 9 timely and accurately; the hydraulic oil pumped by the hydraulic pump 11 is firstly subjected to pressure reduction treatment by the pressure reduction overflow unit 100, and then enters the filter 6 for filtration treatment, and the hydraulic oil entering the filter 6 is the reduced-pressure hydraulic oil, so that the impact of the hydraulic oil on a filter element of the filter 6 is reduced when the low-pressure hydraulic oil enters the filter 6, the failure rate of the filter 6 is reduced, the service life of the filter 6 is prolonged, and meanwhile, compared with the treatment of high-pressure hydraulic oil, the filter 6 for treating the low-pressure hydraulic oil is smaller in volume and lighter in structure.

In order to better filter the hydraulic oil flowing through the first reversing valve 5, the valve body 200 is further provided with a first communicating port Bv1 and a second communicating port Pv which are communicated, the first communicating port Bv1 is communicated with an oil outlet of the pressure reduction overflow unit 100, the second communicating port Pv is communicated with an oil inlet of the first reversing valve 5, the filter 6 is arranged on a passage through which the first communicating port Bv1 is communicated with the second communicating port Pv, the oil inlet of the filter 6 is communicated with the first communicating port Bv1, and the oil outlet of the filter 6 is communicated with the second communicating port Pv.

In order to ensure the safe use of the oil source control valve group, specifically, the relief overflow unit 100 includes: a pressure reducing valve 1 and an overflow valve 2; the oil inlet of the pressure reducing valve 1 is communicated with the oil inlet P of the valve body 200, the oil outlet of the pressure reducing valve 1 is communicated with the oil inlet of the overflow valve 2, and the oil outlet of the overflow valve 2 and the oil outlet of the pressure reducing valve 1 are communicated with the oil return port T of the valve body 200. An overflow valve 2 is arranged between an oil outlet of the pressure reducing valve 1 and an oil return port T, so that a valve core of the overflow valve 2 is opened when the pressure of hydraulic oil in the oil source control valve group rises to a set value due to faults of the pressure reducing valve 1, the hydraulic oil can quickly return to an oil tank through the oil return port T, and the use safety of the oil source control valve group is protected.

In order to avoid the reverse flow of the hydraulic oil in the passage, specifically, the oil source control valve group further comprises: an oil inlet of the check valve 3 is communicated with an oil outlet of the pressure reducing valve 1, and an oil outlet of the check valve 3 is communicated with the first communication port Bv 1.

As shown in fig. 1, specifically, the first direction valve 5 is a two-position three-way electromagnetic valve, and the second oil outlet of the first direction valve 5 is communicated with the oil return port T.

In order to ensure the safe use of the filter 6, as shown in fig. 1, a filtering one-way valve 8 is connected in parallel between the oil inlet and the oil outlet of the filter 6. The filter 6 is protected by the filtering one-way valve 8 under the condition that the filter is blocked, hydraulic oil flows through the filtering one-way valve 8, so that large pressure drop is prevented, the use safety of the filter 6 is ensured, and the normal work of the whole machine is ensured.

In one embodiment, when the oil source control valve group is applied to a hydraulic system, in order to ensure the application safety of the hydraulic system, in particular, the oil source control valve group further comprises: and the energy accumulator 4 is communicated with the oil outlet of the one-way valve 3. As shown in fig. 1, the accumulator 4 is communicated with the oil outlet of the check valve 3 and forms an energy storage port ACC, the energy storage port ACC is disposed on the valve body 200, as shown in fig. 2, when a power element in the hydraulic system is stopped, for example, when the hydraulic pump 11 is stopped, hydraulic oil cannot be supplied to the hydraulic system so that the oil pressure in a pipeline of the hydraulic system is reduced, at this time, the accumulator 4 can release the stored hydraulic oil to the pilot valve 9 through the filter 6 and the first directional valve 5, the hydraulic oil released from the accumulator 4 is filtered through the filter 6, impurities possibly occurring in the hydraulic oil released from the accumulator 4 can be removed, the valve core of the first directional valve 5 is prevented from being blocked, and then the hydraulic oil enters the pilot valve 9 and controls the valve core of the main control valve 12 in the hydraulic system to be opened through the pilot valve 9 for pressure relief, thereby ensuring the safety of the hydraulic actuator, if, in the excavator working process, hydraulic pump 11 halts suddenly, pilot valve 9 can't control the case of main control valve 12 and open under the condition that does not have the hydraulic oil supply, make the digging arm can not in time obtain the hydraulic oil supply and stop, if the digging arm just stops in the midair, will bring very big potential safety hazard, consequently, need descend the digging arm to ground safety position, just accessible energy storage 4 releases the hydraulic oil of storage this moment, the hydraulic oil of release passes through filter 6, first switching-over valve 5 is carried to pilot valve 9, thereby make the case of pilot valve 9 control main control valve 12 open and release pressure, make the digging arm descend to ground safety position, protect construction safety, avoid dangerous the emergence.

In one embodiment, for better control of the hydraulic actuator, as shown in fig. 2, specifically, the oil source control valve group further includes: and the oil inlet of each second reversing valve 7 is communicated with the second communication port Pv, the first oil outlet of each second reversing valve 7 is communicated with the oil return port T of the valve body 200, and the second oil outlet of each second reversing valve 7 is communicated with the control oil port of the hydraulic actuating mechanism. The second reversing valve 7 is a two-position three-way electromagnetic valve, the hydraulic execution mechanism is a traveling motor 13, the traveling motor 13 comprises a motor main body 131 and a motor variable displacement mechanism 132, a first oil outlet of the second reversing valve 7 is communicated with the motor variable displacement mechanism 132, a second oil outlet is communicated with an oil return port T, when the second reversing valve 7 is de-energized, a second oil outlet of the second reversing valve 7 is communicated with the oil return port T, the pressure is zero, the pressure of the motor variable displacement mechanism 132 is zero, at this time, the traveling motor 13 is in a large displacement state, when the second reversing valve 7 is energized, hydraulic oil flowing out of the filter 6 flows to the motor variable displacement mechanism 132 through the second communication port Pv, the second reversing valve 7 and the first oil outlet of the second reversing valve 7, the hydraulic oil flowing into the motor variable displacement mechanism 132 pushes the motor variable displacement mechanism 132 to act, so that the traveling motor 13 is in a small displacement state, and high-low speed switching of the traveling motor 13 is controlled by the second reversing valve 7, and the hydraulic oil flowing through the second reversing valve 7 is filtered by the filter 6, so that the problems of clamping stagnation, low response speed and the like of the second reversing valve 7 caused by the blockage of the valve core of the second reversing valve 7 are avoided.

In another aspect of the present invention, a pilot control system is provided, which includes a hydraulic pump 11, a pilot valve 9, a main control valve 12, at least one set of hydraulic actuators, and the above-mentioned oil source control valve set; the hydraulic pump 11 is used for conveying hydraulic oil to the pilot valve 9 and the hydraulic actuating mechanism, the pilot valve 9 is communicated with the main control valve 12, the pilot valve 9 is used for controlling the opening degree of a valve element of the main control valve 12, the main control valve 12 is installed between the hydraulic pump 11 and the hydraulic actuating mechanism and used for controlling the connection or disconnection of a communication passage between the hydraulic pump 11 and the hydraulic actuating mechanism, and the oil source control valve group is installed on the oil inlet side of the pilot valve 9.

In one embodiment, as shown in fig. 2, there are two hydraulic actuators, which are respectively a traveling motor 13 and a hydraulic cylinder 14, the traveling motor 13 includes a motor main body 131 and a motor variable displacement mechanism 132, the pilot valve 9 has two sets of pilot oil ports, one set is a1 and b1, the other set is a2 and b2, the two sets of pilot oil ports of the pilot valve 9 are respectively communicated with corresponding oil ports on the main control valve 12, the main control valve 12 is installed between the traveling motor 13 and the hydraulic cylinder 14 and the hydraulic pump 11 for controlling the communication or disconnection of the communication paths between the hydraulic pump 11 and the traveling motor 13 and the hydraulic cylinder 14, an oil source control valve set is installed between the pilot valve 9 and the hydraulic pump 11, one hydraulic oil pumped by the hydraulic pump 11 is delivered to the traveling motor 13 and the hydraulic cylinder 14 through the main control valve 12 to drive the traveling motor 13 and the hydraulic cylinder 14 to operate, the other hydraulic oil is delivered to the pilot valve 9 through the oil source control valve set, the hydraulic oil entering the pilot valve 9 is subjected to pressure reduction and impurity removal treatment through the oil source control valve group, and then the hydraulic oil enters the pilot valve 9 to control the valve element opening of the main control valve 12, so that the oil quantity of the hydraulic oil conveyed by the hydraulic pump 11 to the traveling motor 13 and the hydraulic oil cylinder 14 is controlled.

Hydraulic oil enters the pressure reduction overflow unit 100 through an oil inlet P of the valve body 200, the oil inlet P of the valve body 200 is externally connected with the hydraulic pump 11 or is communicated with an oil inlet of the main control valve 12, the oil inlet P of the valve body 200 is directly externally connected with the hydraulic pump 11 or the oil inlet P of the valve body 200 is communicated with the oil inlet of the main control valve 12 according to the arrangement of an oil path during use, and under the condition that the oil inlet P of the valve body 200 is externally connected with the hydraulic pump 11, one path of the hydraulic oil pumped by the hydraulic pump 11 directly enters the pressure reduction overflow unit 100 from the oil inlet P of the valve body 200; under the condition that the oil inlet P of the valve body 200 is communicated with the oil inlet of the main control valve 12, the hydraulic oil pumped by the hydraulic pump 11 enters the oil inlet of the main control valve 12 and simultaneously enters the oil inlet P of the valve body 200 through the oil inlet of the main control valve 12, and then is subjected to pressure reduction treatment through the pressure reduction overflow unit 100.

In another aspect of the present invention, a method for processing hydraulic oil is provided, in which an oil source control valve set is used to process hydraulic oil, the oil source control valve set is installed on an oil inlet side of a pilot valve 9, and the oil source control valve set includes: the valve body 200 is provided with an oil return port T and an oil inlet P and an oil outlet Pr which are communicated, a pressure reduction overflow unit 100, a filter 6 and a first reversing valve 5 are sequentially arranged on a passage where the oil inlet P and the oil outlet Pr are communicated, the oil inlet of the pressure reduction overflow unit 100 is communicated with the oil inlet P of the valve body 200, the filter 6 is arranged between the oil outlet of the pressure reduction overflow unit 100 and the oil inlet of the first reversing valve 5, the first oil outlet of the first reversing valve 5 is communicated with the oil outlet Pr of the valve body 200, the oil outlet Pr of the valve body 200 is communicated with the oil inlet of the pilot valve 9, and the processing method comprises the following steps: hydraulic oil enters from an oil inlet P of a valve body 200 of the oil source control valve group and is subjected to pressure reduction treatment through a pressure reduction overflow unit 100 of the oil source control valve group; the hydraulic oil after pressure reduction is filtered by a filter 6 of the oil source control valve group; the decompressed and filtered hydraulic oil enters the pilot valve 9 through a first reversing valve 5 of the oil source control valve group.

According to the method for processing the hydraulic oil, the pressure reduction treatment is carried out on the hydraulic oil through the pressure reduction overflow unit 100 in the oil source control valve group, the high-pressure hydraulic oil entering from the oil inlet P is reduced to low-pressure hydraulic oil, the impact of the low-pressure hydraulic oil entering the filter 6 for filtration treatment on a filter element of the filter 6 is reduced, the failure rate of the filter 6 is reduced, the service life of the filter 6 is prolonged, the size of the filter 6 for processing the low-pressure hydraulic oil is smaller and smaller compared with the filter 6 for processing the high-pressure hydraulic oil, and when the filtered low-pressure hydraulic oil enters the pilot valve 9 through the first reversing valve 5, the occurrence of valve core blockage and clamping stagnation of the first reversing valve 5 is reduced.

According to the oil source control valve group provided by the invention, the pressure reduction overflow unit is adopted to carry out pressure reduction treatment on the hydraulic oil entering from the oil inlet P, the hydraulic oil after pressure reduction treatment enters the filter, impurities in the hydraulic oil are filtered through the filter, the cleanliness of the hydraulic oil flowing through the first reversing valve is ensured, the problems of clamping stagnation, low response speed and the like caused by valve core blockage of the first reversing valve are avoided, thus the hydraulic oil flowing from the oil outlet of the first reversing valve into the pilot valve is clean after passing through the oil outlet Pr, the use safety of the pilot valve is ensured after the pressure reduction and filtration treatment of the hydraulic oil, and the normal work of the pilot valve is ensured.

According to the oil source control valve group, the pilot control system and the hydraulic oil processing method, the filter is arranged between the oil outlet of the pressure reduction overflow unit and the oil inlet of the first reversing valve, hydraulic oil entering the first reversing valve is filtered, the problems of clamping stagnation and low response speed of the first reversing valve caused by blockage of impurities in the hydraulic oil flowing through the first reversing valve on a valve core of the first reversing valve are solved, the failure rate of the first reversing valve is reduced, the pressure of the hydraulic oil flowing through the filter is reduced through the pressure reduction overflow unit, and the defects of large size and heavy structure of the filter when the high-pressure hydraulic oil is processed are overcome.

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 technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

Those skilled in the art will appreciate that all or part of the steps in the method for implementing the above embodiments may be implemented by a program, which is stored in a storage medium and includes several instructions to enable a single chip, a chip, or a processor (processor) to execute all or part of the steps in the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

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