A loader steering hydraulic control system

Abstract

The application discloses a loader steering hydraulic control system and a two-stage pressure control priority valve, which comprises a first connecting plug, a first communication oil channel is arranged at the lower end of the first connecting plug, a priority valve body is arranged at the outer end of the first connecting plug, a CF interface is arranged at the lower end of the control oil channel, a sequence valve spool is arranged at the inner end of the control oil channel, a second connecting plug is connected to the left end of the priority valve body, a flow-through groove is arranged in the inner part of the valve rod, a second communication oil channel is arranged at the upper end of the vertical throttling port, and a third screw plug is connected to the rear end of the priority valve body. The loader steering hydraulic control system and the two-stage pressure control priority valve are convenient for realizing the communication of the oil pipes in the two-stage pressure control priority valve, improving the steering performance of the loader steering hydraulic system, reducing the energy consumption, reducing the steering force of the steering wheel and improving the maximum steering speed of the steering wheel.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of loaders, in particular to a loader steering hydraulic control system. BACKGROUND

[0002] In the prior art, the loader is provided with a priority valve into which oil is discharged from a steering pump, the priority valve is provided with a CF port for ensuring oil supply to a steering gear according to the required flow rate of the steering gear, and the excess flow rate is supplied to other systems from an EF port, but the control pressure difference of the priority valve is too small, the maximum steering speed is low, the steering force is large, the control pressure difference is too large, and the energy loss is large when not steering, so it is very important to design a two-stage pressure control priority valve with automatic adjustment performance and a loader steering hydraulic system.

[0003] Therefore, the present application provides a loader steering hydraulic control system to solve the above-mentioned problems. SUMMARY

[0004] The present application aims to provide a loader steering hydraulic control system to solve the problems of high energy consumption and large steering control force when not steering in the background art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a loader steering hydraulic control system with a two-stage pressure control priority valve, comprising:

[0006] A first connecting plug is provided with a first communication oil channel at the lower end, and a piston body is connected to the left end of the first connecting plug, a priority valve body is installed at the outer end of the first connecting plug, and a cavity is formed between the piston body and the priority valve body;

[0007] A first connecting oil channel is arranged at the left end of the first communication oil channel, the left end of the first connecting oil channel is connected to a sequence valve cavity, the left end of a control oil channel is provided with a first screw plug, a CF port is installed at the lower end of the control oil channel, a sequence valve spool is arranged in the sequence valve cavity, a flow-through channel is arranged in the sequence valve spool, and a second connecting oil channel is arranged at the right end of the sequence valve spool;

[0008] A spring seat is arranged at the lower end of the sequence valve spool, a vertical spring is connected to the inner end of the spring seat, a second connecting plug is connected to the left end of the priority valve body, a valve rod is arranged at the right end of the second connecting plug, a flow-through groove is arranged in the valve rod, horizontal throttling ports are connected to both ends of the flow-through groove, and a horizontal spring is arranged at the right end of the valve rod;

[0009] A P interface is arranged at the upper inner end of the priority valve body, a vertical throttle is arranged at the lower inner end of the priority valve body, a second communication oil channel is arranged at the upper end of the vertical throttle, a transition oil channel is arranged at the right end of the second communication oil channel, a second screw plug is arranged at the lower end of the first communication oil channel, a safety valve assembly is connected to the right end of the transition oil channel, a third screw plug is connected to the rear end of the priority valve body, and a delivery oil channel is arranged at the front end of the third screw plug to communicate the second communication oil channel with the return oil channel.

[0010] Preferably, the priority valve body is threadedly connected with the first and second connecting plugs, and the piston body is in sliding movement with the priority valve body.

[0011] Preferably, the first connecting oil channel communicates with the sequence valve cavity and the first communication oil channel, and the second connecting oil channel communicates with the delivery oil channel and the return oil channel.

[0012] Preferably, the priority valve body is in relative sliding movement with the valve rod, and a flow-through groove is arranged at the central portion of the valve rod, and horizontal throttles are arranged at the left and right ends of the flow-through groove.

[0013] Preferably, the control oil channel communicates with the first connecting oil channel through the sequence valve cavity and the openable sequence valve spool at the upper end of the sequence valve cavity.

[0014] Preferably, the spring seat is in clamping connection with the vertical spring, and the spring seat is threadedly connected with the priority valve body.

[0015] Preferably, the second and third screw plugs are threadedly connected with the priority valve body, and the inner ends of the second and third screw plugs are connected with pipelines.

[0016] Compared with the prior art, the loader hydraulic control system can improve the steering performance of the loader hydraulic system, reduce energy consumption, reduce the steering force of the steering wheel, and improve the maximum steering speed of the steering wheel.

[0017] 1. The first connecting oil channel, the first communication oil channel, the control oil channel, the sequence valve oil channel, the second communication oil channel and the second connecting oil channel are arranged in communication through the first connecting oil channel, the second communication oil channel, the first communication oil channel and the second connecting oil channel, and the first connecting oil channel and the second connecting oil channel, and the second communication oil channel and the first communication oil channel are arranged in parallel, so as to realize the communication of the two-stage pressure control priority valve internal oil pipe.

[0018] 2. The second connecting plug, the valve rod, the first connecting plug and the second screw plug are arranged in clamping connection with the priority valve body, and the flow-through groove is arranged at the central portion of the valve rod, and horizontal throttles are arranged at the left and right ends of the flow-through groove, and the second and third screw plugs are threadedly connected with the priority valve body, and the inner ends of the second and third screw plugs are connected with pipelines.

[0019] 3、the sequence valve spool is provided with a vertical spring and a spring seat, and the sequence valve spool slides in the sequence valve cavity, and the flow-through channel is inside the sequence valve spool, the spring seat is connected with the vertical spring, and the spring seat is screwed with the priority valve body, through the up and down movement of the sequence valve spool, the sequence valve spool is at the uppermost end when not turning, so that the first connecting oil channel and the second connecting oil channel are communicated, and the sequence valve spool is at the lowermost end when turning, so that the first connecting oil channel and the control oil channel are communicated. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a schematic diagram of the front view cross-sectional structure of the spring seat in the compressed state of the application;

[0021] Figure 2 It is a schematic diagram of the front view cross-sectional structure of the spring seat in the relaxed state of the application; Figure 1 It is a schematic diagram of the working principle of the application;

[0022] Figure 3 It is a schematic diagram of the front view cross-sectional structure of the spring seat in the relaxed state of the application;

[0023] Figure 4 It is a schematic diagram of the working principle of the application; Figure 3

[0024] It is a schematic diagram of the front view cross-sectional structure of the spring seat in the relaxed state of the application; Figure 5

[0025] Figure 6 It is a schematic diagram of the sequence valve spool and the flow-through oil channel structure of the application;

[0026] Figure 7 It is a schematic diagram of the front view structure of the delivery oil channel and the third screw plug connection of the application;

[0027] In the figure: 1, first connecting plug; 2, first communicating oil channel; 3, piston body; 4, cavity; 5, first connecting oil channel; 6, horizontal spring; 7, flow-through groove; 8, second communicating oil channel; 9, priority valve body; 10, valve rod; 11, horizontal throttle; 12, second connecting plug; 13, control oil channel; 14, first screw plug; 15, sequence valve spool; 16, spring seat; 17, vertical spring; 18, second connecting oil channel; 19, vertical throttle; 20, transition oil channel; 21, return oil channel; 22, second screw plug; 23, safety valve assembly; 24, delivery oil channel; 25, third screw plug; 26, P interface; 27, CF interface; 28, flow-through channel; 29, sequence valve cavity; 30, EF interface; 31, Ls interface; 32, T interface. DETAILED DESCRIPTION

[0028] ​Clearly, the described embodiments are merely a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort shall fall within the protection scope of the present application.

[0029] Please refer to Figures 1-7 , the present application provides a kind of technical scheme: a loader steering hydraulic control system, with two-stage pressure control priority valve, comprising: first connecting plug 1, the lower end of first connecting plug 1 is provided with first communication oil channel 2, and the left end of first connecting plug 1 is connected with piston body 3, the left end of first connecting plug 1 is installed with priority valve body 9, and piston body 3 and priority valve body 9 form cavity 4;First connecting oil channel 5, which is opened in the left end of first communication oil channel 2, and the left end of first connecting oil channel 5 is connected with sequence valve cavity 29, the upper end of sequence valve cavity 29 is communicated with control oil channel 13, control oil channel 13 is communicated with CF interface 27, the left end of control oil channel 13 is provided with first screw plug 14, sequence valve spool 15 is arranged in sequence valve cavity 29, and second connecting oil channel 18 is opened in the right side of sequence valve spool 15;Spring seat 16 is arranged at the lower end of sequence valve cavity 29, and the inner end of spring seat 16 is connected with vertical spring 17, the left end of priority valve body 9 is connected with second connecting plug 12, and the right end of second connecting plug 12 is provided with valve stem 10, flow-through groove 7 is opened in the inside of valve stem 10, and the two ends of flow-through groove 7 are connected with horizontal throttle 11, and the right end of valve stem 10 is provided with horizontal spring 6;P interface 26 is arranged on the upper side of priority valve body 9, and vertical throttle 19 is installed at the lower end of second communication oil channel 8 on the lower side of priority valve body 9, the lower end of vertical throttle 19 is Ls interface 31, and transition oil channel 20 is opened at the right end of second communication oil channel 8, the right end of transition oil channel 20 is provided with safety valve assembly 23, the lower end of return oil channel 21 of safety valve assembly 23 is T interface 32 and communicated with the return oil of safety valve assembly 23, the lower end of first communication oil channel is installed with second screw plug 22, the rear end of priority valve body 9 is connected with third screw plug 25, and the front end of third screw plug 25 is provided with delivery oil channel 24, so that second connecting oil channel 18 and return oil channel 21 are communicated;EF interface 30 is further arranged at the rear end of priority valve body 9. The above combination constitutes a loader steering hydraulic control system and two-stage pressure control priority valve.

[0030] As Figure 1 , Figure 3 , Figure 5As shown, the priority valve body 9 is threadedly connected with the first connecting plug 1 and the second connecting plug 12, and the piston body 3 slides in the priority valve body 9. The first connecting oil passage 5 is communicated with the sequence valve cavity 29 and the first communicating oil passage 2, and the second connecting oil passage 18 is communicated with the delivery oil passage 24 and the return oil passage 21. The priority valve body 9 is in sliding motion with the valve stem 10, and the flow passage 7 is arranged in the middle part of the valve stem 10, and the left and right ends of the flow passage 7 are provided with horizontal throttle ports 11, which control the flow and set the control pressure. The first screw plug 14, the second screw plug 22 and the third screw plug 25 are threadedly connected with the priority valve body 9, and the inner ends of the first screw plug 14, the second screw plug 22 and the third screw plug 25 are connected with the pipelines. The first screw plug 14, the second screw plug 22 and the third screw plug 25 block one end of the oil pipeline to prevent pressure relief and oil leakage. The left end of the first connecting oil passage 5 and the control oil passage 13 is connected with the first screw plug 14, and the other end of the control oil passage 13 is connected with the upper end of the sequence valve cavity 29. The second communicating oil passage 8 is communicated with the transition oil passage 20, the right end of the transition oil passage 20 is connected with the safety valve assembly 23, and the load pressure is prevented from being too large.

[0031] As Figure 2 and Figure 4As shown, the steering pump is connected to the P interface 26, and the steering gear is connected to the CF interface 27. When the steering gear on the CF interface 27 is not turned, the pressure on the CF interface 27 is generally lower than 20 bar. The pressure on the CF interface 27 passes through the control oil channel 13 to the upper end of the sequence valve cavity channel 29 and acts on the upper end of the sequence valve spool 15. Since the upper end force of the sequence valve spool 15 is smaller than the spring force of the vertical spring 17 at the lower end, the sequence valve spool 15 is at the upper end of the sequence valve cavity channel 29. The oil at the right end of the piston body 3 passes through the first communication oil channel 2, the first connection oil channel 5, the flow passage 28 in the sequence valve spool 15, the second connection oil channel 18, the oil return channel 21, and the T interface 32 to return to the oil tank. The piston body 3 is at the rightmost position under the action of the horizontal spring at the left end. The horizontal spring 6 is in the longest state, and the spring force is the smallest. Therefore, the valve rod 10 in the priority valve body 9 is in a small control pressure state, which reduces energy consumption. When the steering wheel of the steering gear on the CF interface 27 is turned, the pressure on the CF interface 27 is generally greater than 70 bar. The pressure on the CF interface 27 passes through the control oil channel 13 to the upper end of the sequence valve cavity channel 29 and acts on the upper end of the sequence valve spool 15. Since the upper end force of the sequence valve spool 15 is greater than the spring force of the vertical spring 17 at the lower end, the sequence valve spool 15 is at the lowermost position. The right end of the piston body 3 communicates with the CF interface 27 through the first communication oil channel 2, the first connection oil channel 5, the sequence valve cavity channel 29, and the control oil channel 13. Therefore, the oil in the control oil channel 13 at the upper end of the CF interface 27 enters the right end of the piston body 3 to form high pressure. The oil in the cavity 4 returns to the oil tank through the oil return channel 21 and the T interface 32. The force on the right end of the piston body 3 is much greater than the force on the left end. The piston body 3 slides in the priority valve body 9, so that the piston body 3 moves to the leftmost position. The horizontal spring 6 is compressed, and the spring force is the largest. Therefore, the valve rod 10 in the priority valve body 9 is in a large control pressure state, which is convenient for improving the steering performance of the loader steering hydraulic system, reducing the steering wheel operating force, and improving the maximum steering speed of the steering wheel. This is the use method of the loader steering hydraulic control system and the two-stage pressure control priority valve.

[0032] The standard parts used in the application can be purchased from the market. The special-shaped parts can be ordered according to the description and the drawings. The specific connection mode of each part adopts the conventional means such as bolts, rivets, and welding in the prior art. The mechanical parts and equipment adopt conventional models in the prior art. The circuit connection adopts the conventional connection mode in the prior art, which will not be described in detail here. The contents not described in detail in the specification belong to the prior art known to those skilled in the art.

[0033] Although the present application has been described in detail with reference to the foregoing embodiments, the technical solutions recorded in the foregoing embodiments can be modified, or some of the technical features can be replaced by equivalent features, by those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A loader steering hydraulic control system, comprising a two-stage pressure control priority valve, characterized in that, include: The first connecting plug (1) has a first connecting oil passage (2) at its lower end, and a piston body (3) is connected to the left end of the first connecting plug (1). A priority valve body (9) is installed at the outer end of the first connecting plug (1), and a cavity (4) is formed between the piston body (3) and the priority valve body (9). The first connecting oil passage (5) is located at the left end of the first connecting oil passage (2), and the left end of the first connecting oil passage (5) is connected to the sequence valve cavity (29). The upper end of the sequence valve cavity (29) is connected to the control oil passage (13), and the left end of the control oil passage (13) is provided with a first screw plug (14). The lower end of the control oil passage (13) is equipped with a CF interface (27), and the sequence valve cavity (29) is provided with a sequence valve core (15). The sequence valve core (15) is provided with a flow channel (28), and the right end of the sequence valve core (15) is provided with a second connecting oil passage (18). A spring seat (16) is located at the lower end of the valve core (15) of the sequence valve, and a vertical spring (17) is connected to the inner end of the spring seat (16). A second connecting plug (12) is connected to the left end of the priority valve body (9), and a valve stem (10) is provided at the right end of the second connecting plug (12). A flow groove (7) is provided inside the valve stem (10), and horizontal throttling ports (11) are connected to both ends of the flow groove (7). A horizontal spring (6) is provided at the right end of the valve stem (10). The P interface (26) is located on the upper side of the priority valve body (9), and a vertical throttle port (19) is installed on the lower inner end of the priority valve body (9). A second connecting oil passage (8) is opened at the upper end of the vertical throttle port (19), and an Ls interface (31) is provided at the lower end of the vertical throttle port (19). A transition oil passage (20) is opened at the right end of the second connecting oil passage (8), and a safety valve assembly (23) is connected to the right end of the transition oil passage (20). A second screw plug (22) is installed at the lower end of the first connecting oil passage (2). A third screw plug (25) is connected to the rear end of the priority valve body (9), and a delivery oil passage (24) is opened at the front end of the third screw plug (25). A T interface (32) is provided at the lower end of the return oil passage (21). An EF interface (30) is also provided at the rear end of the priority valve body (9). The first connecting oil passage (5) is connected to the control oil passage (13) and the first connecting oil passage (2), and the second connecting oil passage (18) is connected to the conveying oil passage (24) and the return oil passage (21); The priority valve body (9) slides relative to the valve stem (10), and the flow groove (7) is opened in the middle of the valve stem (10), and horizontal throttling ports (11) are provided at both the left and right ends of the flow groove (7).

2. The loader steering hydraulic control system according to claim 1, characterized in that: The priority valve body (9) is threadedly connected to the first connecting plug (1) and the second connecting plug (12), and the piston body (3) slides left and right in the priority valve body (9).

3. The loader steering hydraulic control system according to claim 1, characterized in that: The control oil passage (13) is connected to the upper end of the sequence valve passage (29).

4. The loader steering hydraulic control system according to claim 1, characterized in that: The upper end of the vertical spring (17) is connected to the valve core (15) of the sequence valve, and the lower end is connected to the spring seat (16). The spring seat (16) is threadedly connected to the priority valve body (9), and the valve core (15) of the sequence valve can slide in the sequence valve cavity (29).

5. A loader steering hydraulic control system according to claim 1, characterized in that: The first plug (14), the second plug (22) and the third plug (25) are all threadedly connected to the priority valve body (9), and the inner ends of the first plug (14), the second plug (22) and the third plug (25) are all connected to the pipeline.

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