Compact load-sensitive proportional valve integrated with hydraulic lock

Abstract

The invention relates to the technical field of hydraulic systems of engineering machinery, and discloses a compact load-sensitive proportional valve of an integrated hydraulic lock, which comprises an oil inlet body and a reversing body which are fixedly connected through a bolt. A main valve element is installed in the middle of the oil inlet body in a sliding mode, a pressure adjusting plug screw, a flow dividing spring, an unloading valve assembly and other components are arranged, the opening pressure can be adjusted, and overpressure unloading is achieved. A hydraulic lock assembly and a pressure compensation valve element are arranged in the reversing body and are designed in a coaxial nesting mode, and a valve element of the hydraulic lock assembly is of a double-conical-face structure. A control oil way is communicated with a main valve element displacement cavity to achieve linkage unlocking, and a load pressure feedback channel is isolated from a control channel through an independent spiral oil channel. A micro filter is arranged at an inlet of the hydraulic lock control oil duct and used for preventing pollution. The invention has the advantages of compact structure, strong anti-pollution capability and fast dynamic response, can realize the accurate matching of a pump valve system and load pressure flow, and is suitable for the control of actuating mechanisms of engineering machinery such as tractors, cranes and the like.

Description

Technical Field

[0001] This invention relates to the field of hydraulic system technology for engineering machinery, specifically a compact load-sensitive proportional valve with integrated hydraulic lock. Background Technology

[0002] In hydraulic systems of construction machinery, the combination of load-sensitive proportional valves and hydraulic locks is widely used. Traditional solutions often use separate installations, requiring the hydraulic lock to be placed externally at the working port of the multi-way valve. This not only occupies a lot of space and has complex pipeline connections, but also increases the risk of leaks and signal interference, making it difficult to adapt to the needs of miniaturized and space-constrained equipment.

[0003] The design of integrating the hydraulic lock into the inside of the multi-way valve can effectively reduce the overall size, eliminate external pipeline leakage, shorten the control signal transmission path, improve the dynamic response speed of the system, and avoid mutual interference between load pressure feedback and hydraulic lock control signal through independent oil passage arrangement.

[0004] However, this integrated design still faces many technical challenges, such as the synchronization of the hydraulic lock and the main valve core, the adaptability under different load conditions, and the convenience of subsequent maintenance and disassembly, which also restrict the promotion and application of the integrated solution.

[0005] In view of this, the present invention proposes a compact load-sensitive proportional valve with integrated hydraulic lock, which solves the above-mentioned technical problems. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a compact load-sensitive proportional valve with an integrated hydraulic lock, thereby solving the problem that existing split-type installation methods are difficult to adapt to the needs of miniaturized and space-constrained equipment.

[0007] The technical solution adopted by the present invention to solve its technical problem is a compact load-sensitive proportional valve with integrated hydraulic lock, including an oil inlet body and a reversing body.

[0008] The main valve core is slidably installed in the middle of the oil inlet body. One end of the main valve core is provided with a pressure regulating plug and a flow dividing spring, and the other end is provided with a fastening plug.

[0009] The reversing body has a built-in hydraulic lock assembly and a pressure compensation valve core. The control oil circuit of the hydraulic lock assembly is connected to the displacement chamber of the main valve core to achieve linkage unlocking. The load pressure feedback channel of the pressure compensation valve core is isolated from the control channel of the hydraulic lock assembly through an independent oil passage.

[0010] The valve core of the hydraulic lock assembly has a double-conical structure, with its small-angle surface facing inward and its large-angle surface facing outward. The hydraulic lock assembly is coaxially arranged with the push rod, and the push rod displacement cavity is connected to the valve stem displacement cavity inside the reversing body.

[0011] Preferably, a direct-acting relief valve is installed on the side wall of the oil inlet body. The oil circuit of the direct-acting relief valve is connected to the valve stem displacement chamber, and together with the main valve core, they form a proportional speed control valve.

[0012] Preferably, the control oil passage inlet of the hydraulic lock assembly is provided with a miniature metal mesh filter with a pore size of no more than 5μm.

[0013] Preferably, electromagnets are symmetrically arranged on both sides of the valve stem, and a return spring and a washer are provided between the electromagnets and the valve stem.

[0014] Preferably, the hydraulic lock assembly and the pressure compensation valve core form a coaxial nested structure, and a compensation plug is provided at the bottom of the reversing body.

[0015] Preferably, the oil inlet body is equipped with an unloading valve assembly and a two-position three-way solenoid valve, and the unloading valve assembly is connected to the oil passage of the main valve core displacement chamber.

[0016] The beneficial effects of this invention are: This invention, through its structural design of coaxial nesting of the hydraulic lock assembly and pressure compensation valve core, and independent spiral oil channel isolation, reduces the volume by more than 40% compared to the traditional split-type solution, making it suitable for space-constrained engineering machinery scenarios. The built-in hydraulic lock assembly facilitates disassembly and maintenance, while the double-cone valve core and micro-filter not only avoid impact during operation but also enhance anti-contamination capabilities and reduce valve core jamming failures. Through the coordinated work of the unloading valve assembly and the direct-acting relief valve, the system pressure overshoot is effectively prevented, ensuring stable operation. The compact linkage structure of each component in this invention ensures zero signal transmission delay and significantly improves dynamic response speed, while eliminating the risk of external pipeline leakage, thus improving the overall reliability and service life of the hydraulic system. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic diagram of the overall connection structure of the present invention; Figure 2 This is a schematic diagram showing the connection between the oil inlet body and the reversing body in this invention. Figure 3 This is a side view of the oil inlet body of the present invention; Figure 4 for Figure 3 Schematic diagram of the AA direction section; Figure 5 for Figure 3 Schematic diagram of the BB direction section in the middle; Figure 6 This is a front view schematic diagram of the commutator; Figure 7 This is a side view of the commutator. Figure 8 for Figure 7 Schematic diagram of cross-section along the CC direction in the middle; Figure 9 This is a schematic diagram illustrating the working principle of the compact load-sensitive proportional valve with integrated hydraulic lock according to the present invention. In the picture: a1. Oil inlet body; a2. Fastening plug; a3. Unloading valve assembly; a4. Valve core; a5. Diverter spring; a6. Pressure regulating screw plug; a7. Direct-acting relief valve; a8. Two-position three-way solenoid valve; b1. Reversing body; b2. Push rod; b3. Hydraulic lock assembly; b4. Pressure compensation valve core; b5. Compensating plug; b6. Valve stem; b7. Gasket; b8. Return spring; b9. Electromagnet. Detailed Implementation

[0019] To make the technical means, creative features, objectives, and effects of this invention easier to understand, the following is a summary. The present invention will be further described in conjunction with specific embodiments.

[0020] The compact load-sensitive proportional valve with integrated hydraulic lock disclosed in this embodiment is mainly used in the control of actuators of construction machinery such as tractor buckets and crane outriggers. Existing split installation methods are difficult to adapt to the needs of miniaturized and space-constrained equipment.

[0021] like Figure 1 and Figure 2 As shown, the core of this embodiment consists of an oil inlet body a1 and a reversing body b1, which are fixedly connected by bolts. The overall volume is reduced by 40% compared with the traditional split-type solution, making it suitable for space-constrained scenarios.

[0022] like Figures 3 to 5 As shown, a cylindrical mounting cavity is machined in the middle of the oil inlet body a1. The main valve core a4 is slidably installed in this cavity. One end of the main valve core a4 is threadedly connected to the pressure regulating plug a6. A flow divider spring a5 is fitted between the pressure regulating plug a6 and the main valve core a4. The compression of the flow divider spring a5 can be adjusted by rotating the pressure regulating plug a6, thereby adjusting the opening pressure of the main valve core a4. The other end of the main valve core a4 is limited by the fastening plug a2 to ensure that there is no axial displacement during sliding.

[0023] like Figure 3 and Figure 4 As shown, a direct-acting relief valve a7 is installed on the left side of the oil inlet body a1, a two-position three-way solenoid valve a8 is installed on the right side, and an unloading valve assembly a3 is installed at the bottom. The oil inlet of the unloading valve assembly a3 is directly connected to the oil passage of the displacement chamber of the main valve core a4 to achieve rapid unloading when the pressure is over-adjusted.

[0024] like Figures 6 to 8As shown, a working oil chamber is machined inward on one side of the reversing body b1. The hydraulic lock assembly b3 is embedded in this chamber for easy independent disassembly and maintenance. Its valve core adopts a double-cone structure, with the small-angle surface facing inward and opposite to the push rod b2, and the large-angle surface facing outward and communicating with the working oil passage. This structure allows the valve core to form throttling speed regulation when it opens, avoiding impact during operation. The hydraulic lock assembly b3 and the pressure compensation valve core b4 adopt a coaxial nesting design, sharing the same mounting cavity, reducing the internal space occupied by the valve body. The bottom of the pressure compensation valve core b4 is fixed by the compensation plug b5. Its load pressure feedback channel and the control channel of the hydraulic lock assembly b3 are independently machined spiral oil passages, achieving physical isolation and preventing signal crosstalk. The push rod b2 is centrally installed inside the reversing body b1, with its two ends abutting against the valve cores of the two hydraulic lock assemblies b3 respectively. The displacement chamber of the push rod b2 is connected to the displacement chamber of the valve stem b6 through a radial oil passage, ensuring that the pressure signal is quickly transmitted to the hydraulic lock assembly b3 when the valve stem b6 moves. Electromagnets b9 are symmetrically installed on both sides of the valve stem b6. The telescopic end of the electromagnet b9 is connected to the return spring b8 through a gasket b7. The other end of the return spring b8 abuts against the end of the valve stem b6, realizing the automatic reset of the valve stem b6. A miniature metal mesh filter is provided at the inlet of the control oil passage of the hydraulic lock assembly b3. The filter pore size is no more than 5μm, which can effectively intercept impurities in the oil, avoid valve core jamming, and improve anti-contamination capability.

[0025] The proportional valve works as follows: When locked, the electromagnet b9 is not energized, the valve stem b6 is in the neutral position under the action of the return spring b8, the control oil circuit of the hydraulic lock assembly b3 is pressureless, the double cone valve core seals the working oil passage under the action of the spring force, and the actuator (such as the oil cylinder) is locked to prevent the load from slipping. In both unlocking and working states, after electromagnet b9 is energized, valve stem b6 moves against the elastic force of return spring b8. The pressure in its displacement chamber is transmitted to the control end of hydraulic lock assembly b3 through the displacement chamber of push rod b2, pushing the double-cone valve core to open. At the same time, hydraulic oil at port P flows to the working port. Simultaneously, the main valve core a4 moves under the action of flow divider spring a5 and hydraulic pressure. Direct-acting relief valve a7 works with main valve core a4 to regulate flow. The highest load pressure is transmitted through the LS circuit to the spring channel of pressure compensation valve core b4, forming a proportional speed control valve a4 with the main valve core, achieving matching of the pump valve system with the actual pressure and flow required by the load. The flow rate at the working port is determined by the opening of main valve core a4 and is independent of the load pressure.

[0026] In terms of protection functions, when the system pressure is over-adjusted, the unloading valve assembly a3 opens quickly to release pressure, ensuring the safe and stable operation of the system.

[0027] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A compact load-sensitive proportional valve with an integrated hydraulic lock, characterized in that, It includes the oil inlet body (a1) and the reversing body (b1). The main valve core (a4) is slidably installed in the middle of the oil inlet body (a1). One end of the main valve core (a4) is provided with a pressure regulating plug (a6) and a flow divider spring (a5), and the other end is provided with a fastening plug (a2). The reversing body (b1) has a built-in hydraulic lock assembly (b3) and a pressure compensation valve core (b4). The control oil circuit of the hydraulic lock assembly (b3) is connected to the displacement chamber of the main valve core (a4) to achieve linkage unlocking. The load pressure feedback channel of the pressure compensation valve core (b4) is isolated from the control channel of the hydraulic lock assembly (b3) through an independent oil passage. The valve core of the hydraulic lock assembly (b3) has a double conical structure, with its small-angle surface facing inward and its large-angle surface facing outward. The hydraulic lock assembly (b3) and the push rod (b2) are arranged coaxially, and the displacement cavity of the push rod (b2) is connected to the displacement cavity of the valve stem (b6) inside the reversing body (b1).

2. The compact load-sensitive proportional valve with integrated hydraulic lock according to claim 1, characterized in that: A direct-acting relief valve (a7) is installed on the side wall of the oil inlet body (a1). The oil circuit of the direct-acting relief valve (a7) is connected to the displacement chamber of the valve stem (b6), and together with the main valve core (a4), they form a proportional speed control valve.

3. The compact load-sensitive proportional valve with integrated hydraulic lock according to claim 1, characterized in that: The hydraulic lock assembly (b3) is equipped with a miniature metal mesh filter at the inlet of the control oil passage, with a filter pore size of no more than 5μm.

4. The compact load-sensitive proportional valve with integrated hydraulic lock according to claim 1, characterized in that: Electromagnets (b9) are symmetrically arranged on both sides of the valve stem (b6), and a return spring (b8) and a washer (b7) are provided between the electromagnets (b9) and the valve stem (b6).

5. The compact load-sensitive proportional valve with integrated hydraulic lock according to claim 1, characterized in that: The hydraulic lock assembly (b3) and the pressure compensation valve core (b4) form a coaxial nested structure, and the bottom of the reversing body (b1) is provided with a compensation screw plug (b5).

6. The compact load-sensitive proportional valve with integrated hydraulic lock according to claim 1, characterized in that: The oil inlet body (a1) is equipped with an unloading valve assembly (a3) ​​and a two-position three-way solenoid valve (a8). The unloading valve assembly (a3) ​​is connected to the oil passage of the displacement chamber of the main valve core (a4).

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