High-precision pressure-stabilizing adjustable pressure reducing valve

Abstract

The present invention discloses a high-precision, pressure-stabilizing, adjustable pressure-reducing valve, comprising a valve body, which is provided with a liquid inlet, a liquid outlet, and a return port. An integral stem-type valve core is housed within the valve body. A pressure-regulating spring is provided on the front end of the stem-type valve core, and a liquid chamber is provided on the rear end of the stem-type valve core. The liquid outlet communicates with the liquid chamber on the rear end of the stem-type valve core via a liquid-passing hole. A guide sleeve is provided at the rear of the stem-type valve core, which communicates with the return port. A sealing gasket is provided between the front end of the guide sleeve and the mating surface of the stem-type valve core. Seal rings are provided at the front and rear of the stem-type valve core, respectively. The front seal ring is always located to the left of the liquid inlet and outlet, while the rear seal ring is always located to the right of the liquid outlet and return port. All dynamic seals do not pass through circumferential cross-holes. This valve can achieve a wide range of pressure adjustment, operates stably, and outputs precise pressure values. The service life of seals and other key components is significantly increased, significantly improving overall reliability and overall lifespan. Liquid return is minimal, pressure and energy losses are minimal, and there is no emulsion leakage throughout the entire process, resulting in greater energy conservation and environmental protection.

Description

Technical Field

[0001] The invention relates to a hydraulic support component for coal mines, in particular to a high-precision pressure-stabilizing adjustable pressure reducing valve. Background Art

[0002] With the advancement of mechanized and automated coal mining technology, the safety and reliability requirements for mining hydraulic products are constantly increasing, and many applications with specialized uses and pressure requirements have emerged. For example, if the hydraulic motor's front end is directly supplied by the emulsion pump station at the working face, the pressure often exceeds the rated pressure of the hydraulic motor, causing damage to the equipment. Installing a separate pump with a lower pressure would be wasteful and inconvenient. Similarly, support equipment within a roadway often requires a supply pressure lower than that of the working face equipment, making a separate pump station unnecessary. Therefore, a relatively stable, adjustable, and precise pressure-reducing control element is required. At the same time, to comply with environmental and economic requirements, the emulsion must not be discharged from the system.

[0003] Prior art, similar to a safety valve with residual liquid recovery, involves releasing pressure when the system's supply pressure exceeds the set point of the safety valve mechanism. The released liquid is then returned to the system via a return line or even discharged directly. Because this safety valve structure lacks the ability to operate frequently, it is easily damaged and has a short lifespan. Furthermore, the pressure fluctuations after decompression are large, and leakage at the pressure relief end can easily occur, resulting in waste of emulsion and environmental pollution.

[0004] The second prior art is a pressure reducing valve with a hollow valve core, which realizes liquid flow through side holes opened on the circumference of the hollow section of the cylindrical valve core. The disadvantages are similar to those of the first prior art. The side holes on the circumference of the valve core repeatedly pass through the sealing belt, and the life of the sealing ring is very limited. In addition, at least 4 sealing belts are arranged on the same circumference, and the resistance of the valve core is very large, resulting in large errors in the pressure reduction pressure values ​​in the initial and later stages of use.

[0005] The third existing technology is a pressure reducing valve using a solid-stem valve core. Although it partially avoids the disadvantages of the first and second existing technologies, the liquid inlet and the return liquid chamber are not specially sealed, resulting in the high-pressure liquid always being connected to the return liquid pipeline, resulting in a large loss of pressure and energy, and the pressure at the liquid outlet is not easy to maintain at a relatively constant value; the liquid outlet and the return liquid port are connected by a slender hole with strict diameter requirements. Once the small hole is blocked, the entire valve will fail. Summary of the Invention

[0006] The purpose of the present invention is to provide a high-precision pressure-stabilizing adjustable pressure reducing valve.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] The high-precision pressure-stabilizing adjustable pressure reducing valve of the present invention comprises a valve body, the valve body being provided with a liquid inlet, a liquid outlet and a liquid return port, the valve body being provided with a rod-type valve core, the front end surface of the rod-type valve core being provided with a pressure-regulating spring, and the rear end surface of the rod-type valve core being provided with a liquid cavity;

[0009] The liquid outlet is connected to or disconnected from the liquid inlet and the liquid return port respectively through the rod-type valve core;

[0010] The liquid outlet is communicated with the liquid cavity at the rear end surface of the rod-type valve core through a liquid-passing hole.

[0011] It can be seen from the technical solution provided by the present invention described above that the high-precision pressure-stabilizing adjustable pressure reducing valve provided by the embodiment of the present invention can achieve a wide range of pressure adjustment, has stable operation, and has a more accurate output pressure value; the service life of seals and other key parts is greatly improved, and the overall reliability and comprehensive life are significantly improved; the return liquid volume is small, the pressure and energy loss are small, there is no emulsion leakage throughout the process, and it is more energy-saving and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic structural diagram of a high-precision pressure-stabilizing adjustable pressure reducing valve provided in an embodiment of the present invention.

[0013] In the picture:

[0014] 1. Pressure-adjusting screw; 2. Pressure-adjusting spring; 3. Spring seat; 4. Rod-type valve core; 5. Sealing gasket; 6. Guide sleeve; 7. Clamping screw plug; 8. Valve body; 9. Liquid-passing hole. DETAILED DESCRIPTION

[0015] The following is a further detailed description of the embodiments of the present invention. The contents not described in detail in the embodiments of the present invention belong to the prior art known to those skilled in the art.

[0016] The preferred embodiment of the high-precision pressure-stabilizing adjustable pressure reducing valve of the present invention is:

[0017] The valve comprises a valve body, the valve body is provided with a liquid inlet, a liquid outlet and a liquid return port, the valve body is provided with a rod-type valve core, the front end surface of the rod-type valve core is provided with a pressure regulating spring, and the rear end surface of the rod-type valve core is provided with a liquid cavity;

[0018] The liquid outlet is connected to or disconnected from the liquid inlet and the liquid return port respectively through the rod-type valve core;

[0019] The liquid outlet is communicated with the liquid cavity at the rear end surface of the rod-type valve core through a liquid-passing hole.

[0020] One end of the pressure regulating spring is connected to the pressure regulating screw, and the other end is pressed against the front end spherical surface of the rod-type valve core through a spring seat.

[0021] A guide sleeve is provided at the rear of the rod valve core and the cavity communicating with the liquid return port. A sealing gasket is provided between the front end of the guide sleeve and the mating surface of the rod valve core. The rear end of the guide sleeve is tightened by a tightening screw plug.

[0022] The front and rear of the rod-type valve core are respectively provided with sealing rings. The front sealing ring is always on the left side of the liquid inlet and liquid outlet, and the rear sealing ring is always on the right side of the liquid outlet and liquid return port.

[0023] The rod-type valve core is an integral rod-type valve core.

[0024] The high-precision pressure-stabilizing adjustable pressure-reducing valve of the present invention solves the problems of poor wear resistance, easy damage and short service life of the existing pressure-reducing valves; secondly, it solves the problem of unstable pressure after pressure reduction in the existing technology; and thirdly, it solves the problem of high energy consumption of the pump station, large amount of pressure-relieved emulsion, and easy waste and pollution during recovery in the existing technology.

[0025] Technical principles, such as Figure 1 As shown:

[0026] The P port is for liquid inlet, which comes from the high-pressure liquid supply pipeline; the A port is for liquid outlet, which supplies the hydraulic motor or hydraulic cylinder to be driven; the T port is for return liquid, which returns directly to the return liquid pipeline of the system.

[0027] Ports P and A are connected by a small orifice with a calculated cross-sectional area. When pressure falls below the set pressure, the emulsion pressure flowing from port A through the small opening in the valve body to the rear end of the stem-type valve core is insufficient to push the spring, and the valve core remains in position. As port P pressure gradually increases, port A pressure also increases to exceed the set pressure, causing the valve core to shift leftward, reducing the valve opening and increasing resistance loss until the valve core reaches a force-balanced position. As pressure at port A continues to rise, the valve core continues to shift leftward, and the passageway at PA changes from a wide opening to a damping orifice with a roughly 0.2mm wide annular groove. Pressure rapidly decreases. If pressure has not yet been reduced to the set pressure, the valve core continues to shift leftward, and the passageway at AT changes from a damping orifice to a wide opening. Pressure at port A also rapidly decreases, causing the valve core to shift rightward and reset.

[0028] The integral stem valve core does not have small holes on the circumference that accelerate the wear of the sealing ring during reciprocating motion.

[0029] The liquid holes at the liquid outlet and the valve core end face do not serve as damping holes, and their diameters are significantly larger than those of similar products, thus avoiding failure of the pressure reducing valve due to blockage by foreign matter or rust.

[0030] The area ratio of the stem valve core and its matching sealing gasket is precisely set. It adopts a single spring structure and uses a high-strength, low-rigidity spring to make the pressure reducing valve more sensitive and the pressure reduction value more accurate.

[0031] The advantages of the present invention are:

[0032] Adopting an integral stem-type valve core and a single spring design, the flow rate is accurately calculated, the structure is simplified while meeting the functional requirements, the spring has better versatility, and the number of parts, especially small parts, is reduced;

[0033] The dynamic seal does not penetrate the hole design, effectively extending the life of the seal;

[0034] The function of the liquid-passing pores is single, and the diameter can be freely determined to avoid blockage;

[0035] The perfect internal sealing belt design ensures tight sealing between the cavities, reduces excessive pressure fluctuations caused by cross-flow, and reduces unnecessary emulsion and pressure loss;

[0036] The adjustable range is significantly larger than similar products on the market. Currently, tests and actual applications have proven that it can cover 10 to 30 MPa pressure reduction adjustment, and the adaptability of the product has been greatly enhanced.

[0037] Specific embodiments, such as Figure 1 As shown:

[0038] Liquid enters port P (the liquid inlet) from the high-pressure supply line, and exits port A (the liquid outlet) to supply the hydraulic motor or cylinder to be driven. Port T (the liquid return port) receives the return liquid, which is directly returned to the system's return line. Ports P and A are connected by a small hole with a calculated cross-sectional area. When the incoming liquid pressure is less than the set pressure, the emulsion pressure at port A, flowing through the liquid-passing hole in valve body 8 and reaching the rear end of the stem-type valve core 4, is insufficient to push the pressure-regulating spring 2, and the valve core 4 remains in position. As the pressure at port P gradually increases, the pressure at port A also increases to a value greater than the set pressure, causing valve core 4 to shift leftward, reducing the valve opening and increasing resistance loss, until valve core 4 reaches a force-balanced position. When the pressure at port A continues to rise, the valve core 4 continues to move left. At this time, the passage of PA changes from a large opening to a damping hole with an annular groove about 0.2 mm wide. At this time, the pressure will drop rapidly. If the pressure has not been reduced to reach the set pressure at this time, the valve core 4 continues to move left, and the passage of AT changes from a damping hole to a large opening. The pressure at port A will also drop rapidly, and the valve core 4 moves right and resets.

[0039] A wide range of pressure settings can be achieved, and the operation is stable, and the output pressure value is more accurate;

[0040] The service life of seals and other key parts is greatly improved, and the overall reliability and comprehensive life are significantly improved;

[0041] The return liquid volume is small, the pressure and energy loss are small, and there is no emulsion leakage throughout the process, which is more energy-saving and environmentally friendly.

[0042] Key technical points of the present invention:

[0043] The integral stem-type valve core and single spring design simplify the structure while meeting the functional requirements, reducing the number of parts, especially small parts;

[0044] The dynamic seal does not penetrate the hole structure, effectively improving the life of the seal;

[0045] The function of the liquid-passing pores at the liquid outlet is unified, and the diameter can be freely determined, reducing the possibility of clogging;

[0046] Perfect internal sealing design ensures tight sealing between cavities, reduces excessive pressure fluctuations caused by cross-flow, and reduces unnecessary emulsion and pressure loss;

[0047] The adjustable range is large, covering 10~30MPa pressure reduction adjustment.

[0048] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A high-precision pressure-stabilizing adjustable pressure reducing valve, characterized in that: The valve comprises a valve body, the valve body is provided with a liquid inlet, a liquid outlet and a liquid return port, the valve body is provided with a rod-type valve core, the front end surface of the rod-type valve core is provided with a pressure regulating spring, and the rear end surface of the rod-type valve core is provided with a liquid cavity; The liquid outlet is connected to or disconnected from the liquid inlet and the liquid return port respectively through the rod-type valve core; The liquid outlet is connected to the liquid cavity at the rear end surface of the rod-type valve core through the liquid-passing hole; One end of the pressure regulating spring is connected to the pressure regulating screw, and the other end is pressed against the front end spherical surface of the rod-type valve core through the spring seat; A guide sleeve is provided in the cavity communicating with the liquid return port at the rear of the rod-type valve core, a sealing gasket is provided between the front end of the guide sleeve and the mating surface of the rod-type valve core, and the rear end of the guide sleeve is tightened by a tightening screw plug; The front and rear of the rod-type valve core are respectively provided with sealing rings, the front sealing ring is always on the left side of the liquid inlet and liquid outlet, and the rear sealing ring is always on the right side of the liquid outlet and liquid return port, and all dynamic seals do not pass through the cross holes on the circumference; The rod-type valve core is an integral rod-type valve core.

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