Pressure reducing valve for hydraulic system

Abstract

The present invention discloses a pressure-reducing valve for a hydraulic system, comprising a valve body and a valve core assembly. The valve core assembly includes an inlet valve housing, an outlet valve housing, a valve seat disposed between the inlet and outlet valve housings, a movably disposed valve core, a push valve movably disposed within the inner cavity of the outlet valve housing and connected to the valve core, and a pressure regulating mechanism connected to the valve body and configured to apply an elastic force to the push valve. The pressure-reducing valve for a hydraulic system of the present invention, by providing the pressure regulating mechanism, can achieve stable control of the outlet pressure, ensuring that the outlet pressure is not affected by fluctuations in the inlet pressure.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal mine fully-mechanized mining hydraulic supports, and in particular relates to a pressure reducing valve for a hydraulic system. Background Art

[0002] Due to structural design defects, the pressure reducing valve used in the hydraulic system cannot achieve stable control of the outlet pressure. When the inlet pressure fluctuates, the outlet pressure will also be affected, which cannot meet the customer's special operating conditions. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a pressure reducing valve for a hydraulic system, which aims to provide two different rated working pressures by using a main inlet and a pressure-reduced outlet to meet the needs of customers in industrial and mining applications.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a pressure reducing valve for a hydraulic system, comprising a valve body and a valve core assembly, wherein the valve core assembly comprises an inlet valve sleeve, an outlet valve sleeve, a valve seat arranged between the inlet valve sleeve and the outlet valve sleeve, a movably arranged valve core, a push valve movably arranged in the inner cavity of the outlet valve sleeve and connected to the valve core, and a pressure regulating mechanism connected to the valve body and used to apply an elastic force to the push valve.

[0005] The pressure regulating mechanism includes a screw sleeve connected to the valve body, a first spring seat movably arranged in the inner cavity of the liquid outlet valve sleeve, a second spring seat movably arranged in the inner cavity of the screw sleeve, a return spring arranged between the first spring seat and the second spring seat, and an adjusting rod connected to the screw sleeve, the first spring seat is in contact with the push valve, and the adjusting rod is in contact with the second spring seat.

[0006] The first spring seat includes a first guide section and a first boss arranged on the first guide section, and the first boss contacts the push valve.

[0007] The second spring seat includes a second guide section and a second boss provided on the second guide section, the second boss is in contact with the adjusting rod, and the reset spring is clamped between the first guide section and the second guide section.

[0008] The threaded sleeve is connected to the valve body by threads.

[0009] The adjusting rod is threadedly connected to the screw sleeve.

[0010] The valve core assembly further includes a locking mechanism, which is configured to prevent the push valve and the valve core from relative movement in the axial direction and to enable the push valve and the valve core to rotate relative to each other.

[0011] The push valve has an accommodating groove for accommodating the locking mechanism, and the valve core has a locking groove for the locking mechanism to be embedded.

[0012] The accommodating grooves are uniformly arranged along the circumference on the side wall of the push valve, and the locking grooves are annular grooves extending along the entire circumference on the outer circular surface of the valve core. A locking mechanism is respectively arranged in each accommodating groove.

[0013] The locking mechanism includes a locking member embedded in the locking groove and the accommodating groove, and a pressing member that applies pressure to the locking member to fix it.

[0014] The pressure reducing valve for a hydraulic system of the present invention can realize stable control of the pressure at the liquid outlet by providing a pressure regulating mechanism, so that the pressure at the liquid outlet will not be affected by the pressure fluctuation at the liquid inlet. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] This manual includes the following drawings, which show the following contents:

[0016] Figure 1 is a cross-sectional view of a pressure reducing valve for a hydraulic system according to the present invention;

[0017] Figure 2 It is a cross-sectional view of the valve core assembly;

[0018] The following are marked in the figure:

[0019] 1. Valve body; 2. Liquid inlet valve sleeve; 3. Valve core; 4. Valve seat; 5. Push valve; 6. Liquid outlet valve sleeve; 7. Return spring; 8. First spring seat; 9. Second spring seat; 10. Screw sleeve; 11. Adjusting rod; 12. Locking piece; 13. Pressing piece. DETAILED DESCRIPTION

[0020] The following is a further detailed description of the specific implementation methods of the present invention through the description of embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and to facilitate its implementation.

[0021] like Figure 1 and Figure 2 As shown, the present invention provides a pressure reducing valve for a hydraulic system, comprising a valve body and a valve core assembly, the valve core assembly comprising an inlet valve sleeve, an outlet valve sleeve, a valve seat arranged between the inlet valve sleeve and the outlet valve sleeve, a movably arranged valve core, a push valve movably arranged in an inner cavity of the outlet valve sleeve and connected to the valve core, and a pressure regulating mechanism connected to the valve body and used to apply an elastic force to the push valve.

[0022] Specifically, if Figure 1 and Figure 2As shown, two valve core assemblies are provided, and two valve chambers are provided in the valve body. A valve core assembly with identical structure is installed in each valve chamber of the valve body. The valve body is provided with an A working port, a B working port, and two P working ports. The two P working ports are provided on opposite surfaces of the valve body. The A working port and one of the P working ports are provided on the same surface of the valve body, while the B working port and the other P working port are provided on another surface of the valve body. The A working port and the B working port are arranged opposite each other, and the two valve core assemblies are located between the A working port and the B working port, and between the two P working ports. The P working port is connected to the hydraulic pump and communicates with both valve chambers. The A and B working ports are used to output the emulsion. The A working port communicates with one of the valve chambers, and the B working port communicates with the other valve chamber. The A and B working ports are not connected. The hydraulic pump pumps the emulsion to the P working port. The oil pressure at the A and B working ports is lower than that at the P working port. If the oil pressure at the P working port fluctuates, both the A and B working ports can stably output emulsion below the fluctuation valley of the P working port. The pressure and output of the A and B working ports can be independently controlled without affecting each other. This allows the use of one main inlet and outlet port with reduced pressure to provide two different rated working pressures, meeting the customer's specific operating requirements.

[0023] like Figure 1 and Figure 2 As shown, the liquid inlet valve sleeve is a cylindrical structure with two open ends and a hollow interior. A first liquid passage hole is provided on the cylindrical sidewall of the liquid inlet valve sleeve, allowing liquid to pass through. An oil inlet hole is provided at one end of the liquid inlet valve sleeve, allowing liquid to pass through. The first liquid passage hole is a circular through-hole extending through the cylindrical sidewall of the liquid inlet valve sleeve. The P working port is connected to the first liquid passage hole. Multiple first liquid passage holes are evenly distributed along the circumference of the cylindrical sidewall of the liquid inlet valve sleeve. A liquid inlet cavity is formed within the liquid inlet valve sleeve. The first liquid passage hole communicates with this cavity, and the emulsion enters the cavity through the first liquid passage hole. Axially, the first liquid passage hole is located between the valve seat and the oil inlet hole of the liquid inlet valve sleeve. The oil inlet hole is a circular hole located at the center of one end surface of the valve body. It communicates with the inner cavity of the liquid inlet valve sleeve and has a smaller diameter than that of the inner cavity of the liquid inlet valve sleeve. The oil inlet hole is coaxial with the valve core. Moreover, the first liquid passage hole provided on the liquid inlet valve sleeve is a circular through hole, and the axis of the first liquid passage hole is perpendicular to the axis of the liquid inlet valve sleeve.

[0024] like Figure 1 and Figure 2As shown, the outlet valve sleeve is a cylindrical structure with two open ends and a hollow interior. A second liquid passage hole is provided on the cylindrical sidewall of the outlet valve sleeve, allowing liquid to pass through. The second liquid passage hole is a circular through-hole extending through the cylindrical sidewall of the outlet valve sleeve. The second liquid passage holes on the outlet valve sleeves of the two valve core assemblies are connected to working port A and working port B, respectively. Multiple second liquid passage holes are evenly distributed along the circumference of the cylindrical sidewall of the outlet valve sleeve. These second liquid passage holes communicate with the inner cavity of the outlet valve sleeve. Emulsion entering the inner cavity of the outlet valve sleeve enters working port A or working port B through the second liquid passage holes. Furthermore, the second liquid passage holes provided on the outlet valve sleeve are circular through-holes, with the axes of the second liquid passage holes perpendicular to the axis of the outlet valve sleeve.

[0025] like Figure 1 and Figure 2 As shown, the valve seat is a circular ring structure. The valve core passes through the center hole of the valve seat and is connected to the push valve. The other end of the valve core is located in the inner cavity of the liquid inlet valve sleeve. A sealing ring is provided between the valve core and the liquid inlet valve sleeve. The valve core is located between the push valve and the oil inlet hole of the liquid inlet valve sleeve. The valve core has a sealing portion and a conical surface is provided on the outer surface of the sealing portion. The end of the valve seat is provided with an arc surface that is sealed and connected to the conical surface of the sealing portion and there is line contact between the two. The arc surface cooperates with the sealing portion to perform a sealing function. The sealing portion is a complete annular structure that is provided on the side wall of the valve core and protrudes outward. It is coaxial with the valve core and is located in the inner cavity of the liquid inlet valve sleeve. The sealing portion and the first liquid hole are located on the same side of the valve seat. When the valve core assembly is in the initial state, the sealing portion contacts the arc surface on the valve seat to achieve sealing. In the following example Figure 2 In the initial state shown, the valve is closed, a seal is established between the valve core and the valve seat, and the inner cavities of the inlet valve sleeve and the outlet valve sleeve are disconnected, resulting in a blocked oil path. When the valve needs to be opened, the seal separates from the valve seat, allowing the inner cavities of the inlet valve sleeve and the outlet valve sleeve to communicate. The valve seat and valve core are made of the same material, 3Cr13. The valve core assembly adopts the aforementioned single-cone inner hole arc surface sealing structure, which is a hard seal, also known as a circular ring seal. Compared to seals made of soft materials, hard seals not only have better sealing performance but are also resistant to ultra-high pressures, effectively extending the service life of the sealing pair, the service life of the valve core assembly, and improving the sealing reliability of the valve core assembly.

[0026] like Figure 1 and Figure 2 As shown, the valve core assembly also includes a locking mechanism that integrally connects the push valve and valve core. This locking mechanism prevents axial movement of the push valve and valve core, while allowing relative rotation. The inlet valve sleeve fits over one longitudinal end of the valve core, while the push valve is attached to the other longitudinal end of the valve core via the locking mechanism. A sealing ring, in the form of an O-ring, is positioned between the push valve and the outlet valve sleeve.

[0027] like Figure 2 As shown, the locking mechanism prevents axial relative movement between the push valve and the valve core, while allowing relative rotation between the push valve and the valve core. This allows the push valve to rotate relative to the valve core about its axis during assembly and disassembly of the valve core assembly and valve body. Compared to conventional threaded connections between the valve core and valve body, the locking mechanism prevents loosening between the valve core and the inlet valve sleeve due to frictional resistance generated by the seal ring mounted on the exterior of the inlet valve sleeve and the inner wall of the valve body, which could lead to separation of the inlet valve sleeve and the valve core. This improves the reliability of the connection between the valve core and the inlet valve sleeve. The push valve has a receiving groove for accommodating the locking mechanism, and the valve core has a locking groove into which the locking mechanism is inserted. The receiving groove is a through hole radially extending through the side wall of the push valve, and multiple receiving grooves are uniformly arranged along the circumference of the side wall of the push valve. The locking groove is an annular groove extending along the entire circumference of the outer surface of the valve core. Multiple locking mechanisms are provided and the multiple locking mechanisms are evenly distributed along the circumference. The number of accommodating grooves is the same as the number of locking mechanisms. Each locking mechanism is embedded in a accommodating groove. The axis of the accommodating groove is perpendicular to the axis of the push valve. The accommodating groove is a through hole radially extending through the side wall of the push valve.

[0028] like Figure 2 As shown, the locking mechanism includes a locking member 12 that is embedded in the locking groove and the receiving groove at the same time, and a pressing member 13 that applies pressure to the locking member 12 to fix it. The locking member 12 is preferably spherical, and the cross-section of the locking groove is semicircular. The pressing member 13 is preferably a screw that is inserted into the receiving groove and is threadedly connected to the push valve. The pressing member 13 is screwed into the receiving groove, pressing the locking member 12 so that a part of the locking member 12 is embedded in the receiving groove and the other part is embedded in the locking groove, thereby realizing the connection between the push valve and the valve core, and allowing the push valve and the valve core to rotate relative to each other without the push valve and the valve core separating. The locking groove is a circular groove, and the locking member 12 is a spherical member that matches the locking groove, which can increase the efficiency of the valve core rotation and reduce friction resistance. During the rotation of the valve core, the locking member 12 can slide circumferentially in the locking groove.

[0029] Preferably, the locking member 12 and the pressing member 13 are made of stainless steel, the push valve is made of 3Cr13, and the valve body is made of 3Cr13, which will prevent the stainless steel from being screwed together when under pressure. The liquid inlet valve sleeve, the liquid outlet valve sleeve, and the valve core are made of the same material.

[0030] like Figure 1 and Figure 2As shown, the pressure regulating mechanism includes a sleeve connected to the valve body, a first spring seat movably disposed within the inner cavity of the outlet valve sleeve, a second spring seat movably disposed within the inner cavity of the sleeve, a return spring disposed between the first and second spring seats, and an adjustment rod connected to the sleeve. The first spring seat contacts the push valve, and the adjustment rod contacts the second spring seat. The return spring is a cylindrical helical spring and a compression spring. The sleeve is a hollow cylinder with open ends. The outlet valve sleeve is sandwiched between the sleeve and the valve seat. The sleeve is inserted into the valve cavity and is threadedly connected to the valve body for easy assembly and disassembly. The sleeve is a hollow cylinder with open ends. The sleeve is coaxial with the outlet valve sleeve, the inlet valve sleeve, the valve seat, the push valve, and the valve core.

[0031] like Figure 1 and Figure 2 As shown, the first spring seat includes a first guide section and a first boss disposed on the first guide section, the first boss contacting the push valve. The first guide section is a circular block-shaped structure, and the first boss is fixedly connected to the first guide section at the center of one end surface of the first guide section. The first boss is spherical and coaxial with the first guide section. The diameter of the first guide section is larger than the diameter of the first boss. The first boss has a first contact surface that contacts the end surface of the push valve. The end surface of the push valve is a plane perpendicular to the axis of the push valve. The first contact surface is the outer surface of the first boss, and the first contact surface is perpendicular to the axis of the first boss. Because the first spring seat is sandwiched between the return spring and the push valve, both the push valve and the return spring exert an axial force on the first spring seat. The first spring seat contacts the end surface of the push valve via the first contact surface disposed on the first boss, forming a planar contact and a stable contact area. This ensures that the first spring seat is subjected to uniform force, so that the first spring seat is only subjected to axial force and is not subject to radial interference. This prevents the return spring from being stuck or bent due to radial force, thereby improving reliability.

[0032] like Figure 1 and Figure 2As shown, the second spring seat includes a second guide section and a second boss disposed on the second guide section. The second boss contacts the adjustment rod, and the return spring is sandwiched between the first and second guide sections. The second guide section is a circular block structure. The first and second guide sections are coaxially arranged and have the same diameter. The second boss is fixedly connected to the second guide section at the center of one end face of the second guide section. The return spring is located between the first and second guide sections. The second boss is spherical and coaxial with the second guide section. The diameter of the second guide section is larger than the diameter of the second boss. The second boss has a second contact surface that contacts the end face of the adjustment rod. The end face of the adjustment rod is a plane perpendicular to the axis of the adjustment rod. The second contact surface is the outer surface of the second boss, and the second contact surface is perpendicular to the axis of the second boss. Since the second spring seat is clamped between the return spring and the adjusting rod, the adjusting rod and the return spring both apply an axial force to the second spring seat. The second spring seat contacts the end face of the adjusting rod through the second contact surface provided on the second boss, forming a planar contact and a stable contact area, which can ensure that the second spring seat is subjected to uniform force, so that the second spring seat is only subjected to axial force and is not subject to radial interference, thereby preventing the return spring from being stuck or bent and deformed due to the radial force, thereby improving reliability.

[0033] like Figure 1 and Figure 2 As shown, the adjusting rod is threadedly connected to the screw sleeve, one end of the screw sleeve is provided with an internal threaded hole, and the outer circumferential surface of the adjusting rod is provided with an external thread. One end of the adjusting rod is located in the inner cavity of the screw sleeve, and the other end of the adjusting rod is located outside the screw sleeve. This end of the adjusting rod is also located outside the valve body, making it convenient for the operator to turn and adjust the output pressure of the liquid outlet (i.e., working port A and working port B). By providing a pressure regulating mechanism with the above structure, stable control of the liquid outlet pressure can be achieved, so that the pressure of the liquid outlet is not affected by fluctuations in the pressure of the liquid inlet.

[0034] The present invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described method. Any non-substantial improvements made using the method concepts and technical solutions of the present invention, or any direct application of the above-described concepts and technical solutions to other situations without modification, fall within the scope of protection of the present invention.

Claims

1. A pressure reducing valve for a hydraulic system, comprising a valve body and a valve core assembly, characterized in that: The valve core assembly includes an inlet valve sleeve, an outlet valve sleeve, a valve seat arranged between the inlet valve sleeve and the outlet valve sleeve, a movably arranged valve core, a push valve movably arranged in the inner cavity of the outlet valve sleeve and connected to the valve core, and a pressure regulating mechanism connected to the valve body and used to apply elastic force to the push valve; The valve core assembly further includes a locking mechanism, which is configured to prevent the push valve and the valve core from relative movement in the axial direction and to enable the push valve and the valve core to rotate relative to each other.

2. The pressure reducing valve for a hydraulic system according to claim 1, characterized in that: The pressure regulating mechanism includes a screw sleeve connected to the valve body, a first spring seat movably arranged in the inner cavity of the liquid outlet valve sleeve, a second spring seat movably arranged in the inner cavity of the screw sleeve, a return spring arranged between the first spring seat and the second spring seat, and an adjusting rod connected to the screw sleeve, the first spring seat is in contact with the push valve, and the adjusting rod is in contact with the second spring seat.

3. The pressure reducing valve for a hydraulic system according to claim 2, characterized in that: The first spring seat includes a first guide section and a first boss arranged on the first guide section, and the first boss contacts the push valve.

4. The pressure reducing valve for a hydraulic system according to claim 3, characterized in that: The second spring seat includes a second guide section and a second boss provided on the second guide section, the second boss is in contact with the adjusting rod, and the reset spring is clamped between the first guide section and the second guide section.

5. The pressure reducing valve for a hydraulic system according to any one of claims 2 to 4, characterized in that: The threaded sleeve is connected to the valve body by threads.

6. The pressure reducing valve for a hydraulic system according to any one of claims 2 to 4, characterized in that: The adjusting rod is threadedly connected to the screw sleeve.

7. The pressure reducing valve for a hydraulic system according to any one of claims 1 to 4, characterized in that: The push valve has an accommodating groove for accommodating the locking mechanism, and the valve core has a locking groove for the locking mechanism to be embedded.

8. The pressure reducing valve for a hydraulic system according to claim 7, characterized in that: The accommodating grooves are uniformly arranged along the circumference on the side wall of the push valve, and the locking grooves are annular grooves extending along the entire circumference on the outer circular surface of the valve core. A locking mechanism is respectively arranged in each accommodating groove.

9. The pressure reducing valve for a hydraulic system according to claim 8, characterized in that: The locking mechanism includes a locking member embedded in the locking groove and the accommodating groove, and a pressing member that applies pressure to the locking member to fix it.

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