Composite safety relief valve

Abstract

The utility model relates to a composite safety relief valve which comprises a shell and a first piston arranged in the shell, inner holes of the shell comprise a hole I and a hole II, and the outer diameter of the first piston is smaller than the diameter of the hole I and larger than the diameter of the hole II; a first fixing block is arranged on the side, away from the hole II, of the first piston, the first fixing block is connected with the first piston through a first spring, and pressure relief holes are formed in the side wall of the first cavity and the first fixing block; the diameter of the second piston is larger than that of the balance hole and smaller than that of the inner hole of the sleeve, and the second fixing block is connected with the second piston through a second spring. When the internal pressure of the coupler is too high, releasing of the internal pressure of the coupler is achieved, through cooperation of the second spring, the second piston and the first piston balance hole, when the internal pressure of the coupler is too low due to cooling, the balance hole is opened, and balance of the internal pressure and the external pressure of the coupler is achieved; the combination of pressure relief and internal and external balance is realized, and the use safety of the coupler is ensured.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, and in particular to a safety valve used in couplings, specifically a composite safety relief valve. Background Technology

[0002] Hydraulic couplings, as important power transmission devices, are widely used in mining machinery, engineering equipment, and power systems. During operation, the working fluid inside the coupling experiences a temperature rise due to friction and impact, leading to a significant increase in internal pressure. Excessive pressure can cause serious safety accidents such as coupling housing rupture and seal failure. Therefore, couplings are typically equipped with pressure relief valves that automatically open to release pressure when the internal pressure exceeds a set threshold, ensuring equipment safety.

[0003] However, most existing pressure relief valves are one-way pressure relief valves, such as spring-loaded safety pressure relief valves. They use the spring force to seal the passage with a steel ball. When the internal pressure is high, the spring force is overcome, causing the steel ball to lose its sealing effect and the internal pressure to be released.

[0004] However, the existing one-way pressure relief scheme still has obvious shortcomings. For example, when the high-temperature liquid inside the coupling gradually cools down, the internal pressure becomes too low, even below 0.1MPa. At this time, the one-way pressure relief valve cannot open in reverse to replenish the gas, resulting in a pressure difference between the inside of the coupling and the outside. This will cause the sealing components to wear or fail due to the negative pressure suction effect. The shell structure will deform under the pressure of the external atmospheric pressure. When restarting, the transmission efficiency will decrease due to the failure of airtightness.

[0005] Currently, in order to address the shortcomings of one-way pressure relief valves, it is common practice to install both one-way pressure relief valves and air supply valves simultaneously to form a dual-valve structure. However, installing valves in different locations increases the single-point failure rate, thereby raising the cost of using the dual-valve structure and increasing the installation space required. Utility Model Content

[0006] This invention addresses the shortcomings of existing technologies by providing a composite safety pressure relief valve that not only achieves pressure relief and balance but also saves space and reduces operating costs.

[0007] This utility model is achieved through the following technical solution: a composite safety pressure relief valve is provided, including a housing and a first piston disposed in the housing. The inner hole of the housing includes a hole I and a hole II arranged sequentially along the axial direction. The diameter of hole I is larger than the diameter of hole II. A stepped surface is formed at the connection between hole I and hole II. The first piston is located in hole I and is in sealing contact with the stepped surface. The outer diameter of the first piston is smaller than the diameter of hole I and larger than the diameter of hole II.

[0008] A first fixing block is fixedly disposed relative to the housing on the side of the first piston away from hole II. The first fixing block is connected to the first piston by a first spring, and a first chamber is formed between the first fixing block and the first piston. A pressure relief hole is provided on the side wall of the first chamber and / or on the first fixing block. A sleeve is sealed and fixedly connected to the side of the first piston away from hole I. A balance hole is provided on the first piston, connecting the first chamber and the inner hole of the sleeve. A second piston is disposed opposite to the balance hole inside the sleeve. The diameter of the second piston is larger than the diameter of the balance hole and smaller than the diameter of the inner hole of the sleeve. A second fixing block is fixedly disposed relative to the sleeve on the side of the second piston away from the balance hole. The second fixing block is connected to the second piston by a second spring, and a second chamber is formed between the second piston and the second fixing block. A flow hole is provided on the second fixing block, connecting the second chamber.

[0009] In use, the first piston is pushed against the stepped surface by the elastic force of the first spring to achieve a seal, and the second piston is blocked by the elastic force of the second spring. When the internal pressure of the coupling is too high, the first piston overcomes the elastic force of the first spring and moves away from the stepped surface, providing a channel for internal pressure release. After the pressure is released, the first piston re-seales with the stepped surface under the action of the first spring. When the internal pressure of the coupling is too low, the second piston compresses the second spring under the action of the internal and external pressure difference, opens the balance hole, and external gas enters the interior through the balance hole to achieve balance.

[0010] As an optimization, the sleeve extends into hole II, forming a pressure relief channel between the outer wall of the sleeve and the inner wall of hole II. This optimized sleeve configuration not only facilitates the installation of the second piston, the second spring, and the second fixing block, but also creates a pressure relief channel between the sleeve and the inner wall of hole II, making it easier to release internal pressure.

[0011] As an optimization, the end face of the first piston is sealed to the stepped surface via a sealing ring. This optimization further improves the sealing effect between the first piston and the stepped surface by adding a sealing ring.

[0012] As an optimization, the second piston has a fixing groove on its side facing the first piston, and a sealing gasket is fixed in the fixing groove. The axial projection of the balance hole is located within the axial projection range of the sealing gasket, and the second piston makes sealing contact with the first piston through the sealing gasket. This optimized solution further improves the sealing effect between the second piston and the first piston by setting a sealing gasket, and the fixing groove facilitates the installation and fixing of the sealing gasket.

[0013] As an optimization, the outer surface of the housing corresponding to hole II is provided with an external thread section, and the external thread section extends to the end of the housing away from hole I. This optimization scheme facilitates the connection between the composite safety relief valve and the coupling by providing the external thread section.

[0014] As an optimization, the outer contour of the housing corresponding to hole I is a regular hexagon, and the wall thickness of the housing corresponding to hole II is greater than the wall thickness of the housing corresponding to hole I. This optimization scheme, by designing the outer contour of the housing corresponding to hole I as a regular hexagon, facilitates the turning of this composite safety relief valve, making installation and operation more convenient. The wall thickness setting ensures the strength of the housing corresponding to hole II.

[0015] As an optimization, pressure relief holes are provided on both the side wall of the first chamber and the first fixing block. The pressure relief holes on the side wall of the first chamber are evenly distributed circumferentially, while the pressure relief holes on the first fixing block are axially continuous and hexagonal. The first fixing block is connected to the shell via external threads. This optimized design facilitates rapid pressure relief, and the hexagonal shape of the pressure relief holes on the first fixing block facilitates rotational installation, improving assembly and disassembly efficiency.

[0016] As an optimization, the first spring, first piston, balance hole, second piston, second spring, and sleeve are coaxially arranged. This optimized arrangement improves the coaxiality of the pressure on the first and second pistons, thereby ensuring the uniformity of the force on the first and second pistons and improving the sealing effect. At the same time, it improves the uniformity of the pressure relief channel on the outside of the sleeve, thus improving the pressure relief effect.

[0017] As an optimization, the first piston includes a piston plate and a sealing platform extending from the piston plate away from the first fixing block. A balance hole is located at the center of the piston plate. The outer diameter of the sealing platform is larger than the outer diameter of the piston plate but smaller than the inner diameter of hole I. The inner diameter of the sealing platform is greater than or equal to the inner diameter of hole II. This optimized design increases the contact area between the first piston and the stepped surface by providing a sealing platform, thereby improving the sealing effect between the first piston and the stepped surface.

[0018] As an optimization, the inner diameter of the first spring is larger than the outer diameter of the piston plate and smaller than the outer diameter of the sealing platform. The end of the first spring away from the first fixing block is sleeved on the piston plate and abuts against the sealing platform. This optimized solution utilizes the piston plate and sealing platform structure of the first piston to install the end of the first spring, thereby achieving the positioning of the end of the first spring.

[0019] The beneficial effects of this utility model are as follows: by setting the first spring and the first piston, the internal pressure of the coupling is released when it is too high; by cooperating with the second spring, the second piston and the balance hole of the first piston, the balance hole is opened when the internal pressure of the coupling is too low due to cooling, thus achieving pressure balance inside and outside the coupling; the combination of pressure relief and internal and external balance is achieved, ensuring the safe use of the coupling. Attached Figure Description

[0020] Figure 1This is a schematic diagram of the internal structure of this utility model;

[0021] Figure 2 This is a schematic diagram of the pressure relief state of this utility model;

[0022] Figure 3 This is a schematic diagram of the internal and external equilibrium state of this utility model;

[0023] Figure 4 This is a schematic diagram of the external structure of this utility model;

[0024] As shown in the figure:

[0025] 1. First fixing block, 2. First spring, 3. Balance hole, 4. First piston, 5. Housing, 6. Second spring, 7. Sleeve, 8. External thread section, 9. Second fixing block, 10. Second piston, 11. Pressure relief hole, 12. Sealing ring, 13. Sealing gasket, 14. Stepped surface, 15. Sealing platform. Detailed Implementation

[0026] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0027] like Figure 1 The composite safety relief valve shown includes a housing 5 and a first piston 4 disposed within the housing 5. The inner bore of the housing includes a hole I and a hole II arranged sequentially along the axial direction. The diameter of hole I is larger than the diameter of hole II. A stepped surface 14 is formed at the connection between hole I and hole II. The stepped surface 14 faces hole I and is used to cooperate with the first piston to form a seal.

[0028] The first piston 4 is located inside hole I and is in sealing contact with the stepped surface 14. The outer diameter of the first piston is smaller than the diameter of hole I but larger than the diameter of hole II, creating a gap between the outer surface of the first piston and the inner wall of hole I. In this embodiment, the end face of the first piston away from the first spring is in sealing contact with the stepped surface through a sealing ring 12. Specifically, a sealing groove is formed on the end face of the first piston, and the sealing ring is adhered and fixed in the sealing groove. The sealing groove is circumferentially continuous. By setting the sealing ring, the sealing effect between the first piston and the stepped surface is improved in the non-pressure relief state.

[0029] A first fixing block 1 is provided on the side of the first piston away from hole II, which is fixedly disposed relative to the housing. The first fixing block 1 is connected to the first piston 4 through a first spring 2. The first piston is pressed against the stepped surface under the action of the first spring. A first chamber is formed between the first fixing block and the first piston. A pressure relief hole 11 is provided on the side wall of the first chamber and / or on the first fixing block.

[0030] As a solution, the first piston in this embodiment includes a piston plate and a sealing platform 15 extending from the piston plate away from the first fixing block. A balance hole is located at the center of the piston plate. The outer diameter of the sealing platform is larger than the outer diameter of the piston plate and smaller than the inner diameter of hole I. The inner diameter of the sealing platform is greater than or equal to the inner diameter of hole II. The inner diameter of the first spring is larger than the outer diameter of the piston plate and smaller than the outer diameter of the sealing platform. The end of the first spring 2 away from the first fixing block is sleeved on the piston plate and abuts against the sealing platform 15, ensuring that the first piston is subjected to uniform force along the axial direction.

[0031] In this embodiment, pressure relief holes are provided on both the side wall of the first chamber and the first fixing block. The pressure relief holes on the side wall of the first chamber are evenly distributed circumferentially, while the pressure relief holes on the first fixing block are axially continuous and are regular hexagonal. The first fixing block is connected to the housing via an external thread, and the housing has an internal thread adapted to the external thread. The regular hexagonal shape of the pressure relief holes on the first fixing block in this embodiment facilitates rotation of the first fixing block using a hexagonal tool, thereby facilitating threaded connection with the housing.

[0032] A sleeve 7 is sealed and fixed to the side of the first piston away from hole I. The sleeve 7 extends axially into hole II. A pressure relief channel is formed between the outer wall of the sleeve and the inner wall of hole II. When the pressure is released, the first piston squeezes the spring and separates from the stepped surface. The gas and liquid inside the coupling enter the first chamber in sequence through the pressure relief channel, the gap between the first piston and the stepped surface, and the gap between the first piston and the inner wall of hole I, and flow out through the pressure relief hole.

[0033] The first piston has a balance hole 3 that connects the first chamber to the inner hole of the sleeve. The balance hole is located at the center of the first piston and extends through the first piston axially. The sleeve 7 has a second piston 10 that is disposed opposite to the balance hole. The diameter of the second piston is larger than the diameter of the balance hole but smaller than the diameter of the inner hole of the sleeve. The second piston pushes against the first piston, thus blocking the balance hole. A gap is formed between the outer surface of the second piston and the inner wall of the sleeve.

[0034] A second fixing block 9 is provided on the side of the second piston away from the balance hole, and is fixedly disposed relative to the sleeve. The second fixing block 9 is connected to the second piston 10 through a second spring 6. Under the action of the second spring, the second piston presses against the first piston to ensure the sealing of the balance hole. A second chamber is formed between the second piston and the second fixing block, and a flow hole communicating with the second chamber is provided on the second fixing block. In this embodiment, the outer circular surface of the second fixing block is connected to the inner wall of the sleeve through a thread.

[0035] In this embodiment, the second piston has a fixing groove on its side facing the first piston. A sealing gasket 13 is fixedly attached to the fixing groove. The axial projection of the balance hole is located within the axial projection range of the sealing gasket. The second piston is in sealing contact with the first piston through the sealing gasket, which improves the sealing effect of the balance hole when the internal and external pressures of the coupling are balanced.

[0036] The outer surface of the housing corresponding to hole II is provided with an external thread section 8, which extends to the end of the housing away from hole I. The thread section is used for connection with the coupling. The outer contour of the housing corresponding to hole I is a regular hexagon, and the wall thickness of the housing corresponding to hole II is greater than the wall thickness of the housing corresponding to hole I. By setting it to a regular hexagon, it is convenient to screw the housing for installation. Pressure relief holes are provided on the plane corresponding to each side of the regular hexagon for easy processing.

[0037] In this embodiment, the first spring 2, the first piston 4, the balance hole 3, the second piston 10, the second spring 6, and the sleeve 7 are arranged coaxially.

[0038] The composite safety relief valve in this embodiment is fixedly connected to a coupling via threads. The valve body containing the first piston and the first spring is valve A1, and the valve body containing the second piston and the second spring is valve A2. The working principle of this embodiment will be explained below using an example where the set working pressure of valve A1 is 1 MPa and the set working pressure of valve A2 is 0.1 MPa:

[0039] When the internal pressure of the coupling reaches 1 MPa, such as Figure 2 As shown, under internal pressure, the first piston moves to the left, compressing the first spring. The first piston then leaves the stepped surface. The gas and liquid inside the coupling sequentially enter the first chamber through the pressure relief channel, the gap between the first piston and the stepped surface, and the gap between the first piston and the inner wall of hole I, and flow out through the pressure relief hole, thus releasing the pressure. After the pressure is released, when the internal pressure of the coupling is lower than 1 MPa, the first piston re-seales with the stepped surface under the action of the first spring.

[0040] When the liquid inside the coupling cools, causing the pressure to drop below 0.1 MPa, such as Figure 3 As shown, the second piston moves to the right under the action of the internal and external pressure difference, compresses the second spring, opens the balance hole, and the external gas enters the second chamber in sequence through the balance hole, the gap between the second piston and the first piston, and the gap between the second piston and the sleeve. It then enters the coupling from the flow hole in the second fixed block, realizing the pressure balance between the inside and outside of the coupling. Then, the elastic force of the second spring is used to make the second piston re-seal the balance hole.

[0041] Of course, the above description is not limited to the examples above. Technical features of this utility model not described can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A composite safety relief valve, characterized in that: The device includes a housing (5) and a first piston (4) disposed inside the housing (5). The inner hole of the housing includes a hole I and a hole II arranged sequentially along the axial direction. The diameter of hole I is larger than the diameter of hole II. A stepped surface (14) is formed at the connection between hole I and hole II. The first piston (4) is located inside hole I and is in sealed contact with the stepped surface (14). The outer diameter of the first piston is smaller than the diameter of hole I and larger than the diameter of hole II. A first fixing block (1) is provided on the side of the first piston away from the hole II and is fixedly disposed relative to the housing. The first fixing block (1) is connected to the first piston (4) through the first spring (2). A first chamber is formed between the first fixing block and the first piston. A pressure relief hole (11) is provided on the side wall of the first chamber and / or on the first fixing block. A sleeve (7) is sealed and fixed to the side of the first piston away from hole I. A balance hole (3) is opened on the first piston to connect the first chamber and the inner hole of the sleeve. A second piston (10) is provided in the sleeve and is arranged opposite to the balance hole. The diameter of the second piston is larger than the diameter of the balance hole and smaller than the diameter of the inner hole of the sleeve. A second fixing block (9) is provided on the side of the second piston away from the balance hole and is fixed opposite to the sleeve. The second fixing block (9) is connected to the second piston (10) through a second spring (6). A second chamber is formed between the second piston and the second fixing block. A flow hole is opened on the second fixing block to connect the second chamber.

2. The composite safety relief valve according to claim 1, characterized in that: The sleeve (7) extends into the hole II, and a pressure relief channel is formed between the outer wall of the sleeve and the inner wall of the hole II.

3. The composite safety relief valve according to claim 1, characterized in that: The end face of the first piston is in sealed contact with the stepped surface through a sealing ring (12).

4. A composite safety relief valve according to claim 1, characterized in that: The second piston has a fixing groove on its side facing the first piston, and a sealing gasket (13) is fixed in the fixing groove. The projection of the balance hole along the axial direction is located within the projection range of the sealing gasket along the axial direction, and the second piston is in sealed contact with the first piston through the sealing gasket.

5. A composite safety relief valve according to claim 1, characterized in that: The outer surface of the housing corresponding to hole II is provided with an external thread section (8), and the external thread section extends to the end of the housing away from hole I.

6. A composite safety relief valve according to claim 5, characterized in that: The outer contour of the shell corresponding to hole I is a regular hexagon, and the wall thickness of the shell corresponding to hole II is greater than the wall thickness of the shell corresponding to hole I.

7. A composite safety relief valve according to claim 1, characterized in that: Pressure relief holes are provided on the side wall of the first chamber and the first fixing block. The pressure relief holes on the side wall of the first chamber are evenly distributed circumferentially, and the pressure relief holes on the first fixing block are axially continuous and are regular hexagonal. The first fixing block is connected to the shell by external thread.

8. A composite safety relief valve according to claim 1, characterized in that: The first spring (2), the first piston (4), the balance hole (3), the second piston (10), the second spring (6), and the sleeve (7) are arranged coaxially.

9. A composite safety relief valve according to claim 1, characterized in that: The first piston includes a piston plate and a sealing platform (15) extending from the piston plate away from the side where the first fixing block is located. The balance hole is located at the center of the piston plate. The outer diameter of the sealing platform is greater than the outer diameter of the piston plate and less than the inner diameter of hole I. The inner diameter of the sealing platform is greater than or equal to the inner diameter of hole II.

10. A composite safety relief valve according to claim 9, characterized in that: The inner diameter of the first spring is greater than the outer diameter of the piston plate and less than the outer diameter of the sealing platform. The end of the first spring (2) away from the first fixed block is sleeved on the piston plate and pushes against the sealing platform (15).

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