Dual-fuel pressure regulating valve with pressure relief structure

Abstract

The utility model relates to the technical field of pressure regulating valves, in particular to a dual-fuel pressure regulating valve with a pressure relief structure, which comprises a shell, a second fuel inlet end cover, a control piston, a pressure relief valve rod, a limiting component, a first elastic component, a second elastic component, a third elastic component, a first fuel control valve rod and a plug. The first fuel pressure can be controlled according to the second fuel pressure, the pressure relief structure is not affected by other parts of the pressure regulating valve, pressure relief can be triggered in time according to the first fuel pressure and the second fuel pressure, the first fuel pressure is made to be lower than the second fuel pressure, and fixed deviation is maintained. The pressure relief structure is not affected by movement of other parts of the pressure regulating valve, pressure relief is independently controlled, pressure relief response is fast, and the pressure regulating valve is simple in structure and easy to machine. According to the pressure relief structure, the bias force of the spring can be adjusted according to different design requirements, and the pressure deviation between the first fuel and the second fuel is accurately controlled.

Description

Technical Field

[0001] The utility model relates to the technical field of pressure regulating valves, in particular to a dual-fuel pressure regulating valve with a pressure relief structure. Background Art

[0002] In the HPDI system, the diesel and natural gas pressures must be precisely controlled. The electronic control technology for diesel pressure is very mature, but due to the compressibility of gas, the electronic control technology for natural gas pressure is not yet mature. Therefore, a pressure regulating valve component is added to use diesel pressure to control natural gas pressure.

[0003] However, there are currently no mature dual-fuel pressure control valves, and existing products have shortcomings such as inaccurate control and slow exhaust response when controlling natural gas pressure. Summary of the Invention

[0004] The utility model provides a dual-fuel pressure regulating valve with a pressure relief structure, which can control the first fuel pressure according to the second fuel pressure. The pressure relief structure is not affected by other components of the pressure regulating valve and can trigger pressure relief in time according to the first fuel pressure and the second fuel pressure, so that the first fuel pressure is lower than the second fuel pressure and maintains a fixed deviation, thereby solving the technical problems mentioned in the background technology.

[0005] The technical solution of the utility model is as follows: A dual-fuel pressure regulating valve with a pressure relief structure, comprising: a housing, a second fuel inlet end cover, a control piston, a pressure relief valve stem, a limit assembly, a first elastic assembly, a second elastic assembly, a third elastic assembly, a first fuel control valve stem, and a plug;

[0006] The control piston, the pressure relief valve stem, the limit assembly, the first elastic assembly, the second elastic assembly, the third elastic assembly, the first fuel control valve stem, and the plug are all installed in the housing;

[0007] The second fuel inlet end cover is provided at the upper end of the housing, the control piston is slidably provided in the housing with the outer side wall of the control piston close to the inner side wall of the housing, and the first elastic component is installed between the control piston and the housing;

[0008] The limit assembly is installed at the upper end of the control piston, the pressure relief valve rod is slidably arranged inside the control piston with the outer side wall of the pressure relief valve rod close to the inner side wall of the control piston, and the third elastic assembly is installed between the pressure relief valve rod and the control piston;

[0009] The plug is provided at the lower end of the housing, the second elastic component is installed between the first fuel control valve stem and the plug, and the upper end sealing surface of the first fuel control valve stem abuts against the housing;

[0010] A second fuel inlet is formed on the second fuel inlet end cover, a second fuel cavity is formed between the second fuel inlet end cover and the upper surface of the control piston, and the second fuel inlet is in communication with the second fuel cavity;

[0011] The lower surface of the control piston and the housing form a first fuel cavity, the side wall of the housing is provided with a first fuel outlet, and the first fuel cavity is communicated with the first fuel outlet;

[0012] A first fuel pressure relief chamber is formed between the pressure relief valve stem and the control piston, and a first fuel pressure relief port is formed on the side wall of the housing. The first fuel pressure relief port is communicated with the first fuel pressure relief chamber, and the first fuel pressure relief chamber is communicated with the first fuel chamber when the third elastic component is extended.

[0013] A first fuel inlet cavity is formed between the first fuel control valve stem and the shell, and a first fuel inlet is opened on the side wall of the shell. The first fuel inlet is connected to the first fuel inlet cavity. The first fuel inlet cavity is connected to the first fuel cavity when the second elastic component is compressed and when the first elastic component is compressed.

[0014] Furthermore, a first sealing member is provided between the second fuel inlet end cover and the housing.

[0015] Furthermore, a second seal and a third seal are provided between the control piston and the housing, a pressure relief channel is provided on the control piston, and the second seal and the third seal are respectively located at the upper and lower sides of the pressure relief channel.

[0016] Furthermore, a fourth sealing member is provided between the pressure relief valve stem and the control piston, and the fourth sealing member is used to separate the second fuel chamber from the first fuel pressure relief chamber.

[0017] Furthermore, the first elastic component, the second elastic component, and the third elastic component are all springs.

[0018] Furthermore, the limiting assembly is a limiting nut, which is threadedly connected to the control piston.

[0019] Furthermore, a communication channel is provided at the bottom end of the control piston, and the communication channel is used to connect the first fuel pressure relief chamber and the first fuel chamber.

[0020] Furthermore, a sealing gasket is provided inside the control piston, the sealing gasket is fixed by a fixing nut, and the sealing gasket abuts against the sealing surface of the pressure relief valve stem.

[0021] The beneficial effects of the present invention are as follows: the pressure relief structure of the present invention is not affected by the movement of other components of the pressure regulating valve, independently controls the pressure relief, and has a fast pressure relief response. The present invention has a simple structure and is easy to process. The pressure relief structure of the present invention can adjust the spring bias force according to different design requirements to accurately control the pressure deviation between the first fuel and the second fuel. A sealing ring is used between the pressure relief valve stem and the control piston of the present invention to seal the high-pressure second fuel. The sealing ring has low friction and good sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the utility model in the pressure relief state.

[0023] Figure 2 It is a structural diagram of the working state of the utility model. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts should fall within the scope of protection of the present invention.

[0025] In an embodiment of the present invention, Figure 1 and Figure 2 The schematic diagram is provided based on the structure of a dual fuel pressure regulating valve with a pressure relief structure. Figure 1 and Figure 2 As shown, the utility model includes: a housing 1, a second fuel inlet end cover 2, a control piston 3, a pressure relief valve stem 5, a limit assembly 4, a first elastic assembly 15, a second elastic assembly 16, a third elastic assembly 14, a first fuel control valve stem 8, and a plug 9;

[0026] The control piston 3, pressure relief valve stem 5, stopper assembly 4, first elastic assembly 15, second elastic assembly 16, third elastic assembly 14, first fuel control valve stem 8, and plug 9 are all installed within the housing 1. The second fuel inlet end cap 2 is disposed at the upper end of the housing 1. The control piston 3 slides within the housing 1, with its outer wall abutting against the inner wall of the housing 1. The first elastic assembly 15 is installed between the control piston 3 and the housing 1. The stopper assembly 4 is installed at the upper end of the control piston 3. The pressure relief valve stem 5 slides within the control piston 3, with its outer wall abutting against the inner wall of the control piston 3. The third elastic assembly 14 is installed between the pressure relief valve stem 5 and the control piston 3. The plug 9 is disposed at the lower end of the housing 1. The second elastic assembly 16 is installed between the first fuel control valve stem 8 and the plug 9. The upper end sealing surface of the first fuel control valve stem 8 abuts the housing 1. A second fuel inlet 20 is defined on the second fuel inlet end cap 2. A second fuel cavity 21 is formed between the second fuel inlet end cap and the upper surface of the control piston 3. The second fuel inlet 20 communicates with the second fuel cavity 21. A first fuel cavity 23 is defined between the lower surface of the control piston 3 and the housing 1. A first fuel outlet 18 is defined on the sidewall of the housing 1. The first fuel cavity 23 communicates with the first fuel outlet 18. A first fuel pressure relief cavity 24 is defined between the pressure relief valve stem 5 and the control piston 3. A first fuel pressure relief port 19 is defined on the sidewall of the housing 1. The first fuel pressure relief port 19 communicates with the first fuel pressure relief cavity 24. The first fuel pressure relief cavity 24 communicates with the first fuel cavity 23 when the third elastic component 14 is extended. A first fuel inlet chamber 22 is formed between the first fuel control valve stem 8 and the shell 1. A first fuel inlet 17 is opened on the side wall of the shell 1. The first fuel inlet 17 is connected to the first fuel inlet chamber 22. The first fuel inlet chamber 22 is connected to the first fuel chamber 23 when the second elastic component 16 is compressed and the first elastic component 15 is compressed.

[0027] A first sealing member 10 is provided between the second fuel inlet cover 2 and the housing 1 to prevent the second fuel in the second fuel cavity 21 from leaking out.

[0028] Among them, a second seal 11 and a third seal 12 are arranged between the control piston 3 and the housing 1. A pressure relief channel is opened on the control piston 3. The second seal 11 and the third seal 12 are respectively located on the upper and lower sides of the pressure relief channel, and are used to separate the pressure relief channel and the first fuel pressure relief port up and down.

[0029] A fourth sealing member 13 is provided between the pressure relief valve stem 5 and the control piston 3 , and the fourth sealing member 13 is used to separate the second fuel chamber 21 from the first fuel pressure relief chamber 24 .

[0030] The first elastic component 15 , the second elastic component 16 , and the third elastic component 14 are all springs.

[0031] The limiting assembly 4 is a limiting nut, which is threadedly connected to the control piston 3 .

[0032] A communication channel is provided at the bottom end of the control piston 3 , and the communication channel is used to connect the first fuel pressure relief chamber 24 with the first fuel chamber 23 .

[0033] A sealing gasket 7 is provided inside the control piston 3 and fixed by a fixing nut 6. The sealing gasket 7 abuts against the sealing surface of the pressure relief valve stem 5. The sealing gasket 7 may be a plastic sealing gasket.

[0034] In the present invention, the control piston 3 and first fuel control valve stem 8 are coaxially mounted within the housing 2. The first fuel pressure relief valve stem 5 and gasket 7 are mounted within the control piston 3. The limit assembly 4 is threadedly tightened onto the control piston 3, and the retaining nut 6 is threadedly compressed against the gasket 7. The second fuel inlet end cap 2 is threadedly tightened onto the housing 1. A first elastic assembly is mounted between the first fuel pressure relief valve stem 5 and the gasket retaining nut 6. Under the preload force of the first elastic assembly 14, the upper end of the first fuel pressure relief valve stem 5 contacts the lower end surface of the limit nut 4. A second elastic assembly 15 is mounted between the control piston 3 and the housing 1. Under the preload force of the second spring 15, the upper end of the control piston 3 contacts the lower end surface of the second fuel inlet end cap 2. A third elastic assembly 16 is mounted between the first fuel control valve stem 8 and the plug 9. Under the preload force of the third elastic assembly 16, the sealing surface of the first fuel control valve stem 8 contacts the housing 1. The plug 9 is threadedly tightened onto the housing 1.

[0035] Working principle of the utility model: The utility model is a pressure regulating valve structure for maintaining a pressure deviation between two fuels. The second fuel inlet 20 is connected to the fuel rail, the first fuel inlet 17 is connected to the gas tank, the first fuel outlet 18 is connected to the gas rail, and the first fuel pressure relief port 19 is connected to the recovery device or the atmosphere. When the second fuel inlet 20 is not connected to the high-pressure fuel, the control piston 3 contacts the lower end surface of the second fuel inlet end cover 2 under the action of the spring preload force, the first fuel pressure relief valve stem 5 contacts the lower end surface of the pressure relief valve stem limit nut 4 under the action of the spring preload force, and the first fuel control valve stem 8 is pressed against the housing 2 under the action of the spring preload force (such as Figure 1When the second fuel inlet 20 is connected to the high-pressure fuel, the high-pressure fuel enters the second fuel chamber 21. Under the action of the hydraulic pressure, the first fuel pressure relief valve stem 5 overcomes the first spring 14 and moves downward until its sealing surface contacts the sealing gasket 7. At the same time, under the action of the hydraulic pressure, the control piston 3 overcomes the second elastic component 15 and moves downward. The lower end surface of the control piston 3 contacts the first fuel control valve stem 8, and pushes the first fuel control valve stem 8 to move downward, overcoming the third elastic component 16, until the lower end surface of the control piston 3 contacts the housing 1 (as shown). Figure 2 As shown in the figure, when high-pressure first fuel enters the first fuel inlet chamber 22 through the first fuel inlet 17, the first fuel enters the first fuel chamber 23 through the gap between the first fuel control valve stem 8 and the housing 1, and enters the gas rail through the first fuel outlet 18. When the pressure differential between the second fuel chamber 21 and the first fuel chamber 23 (second fuel pressure minus first fuel pressure) reaches the set value a, the control piston 3 and the first fuel control valve stem 8 stabilize in a predetermined open position. When the pressure differential between the first and second fuel chambers 23 and 21 falls below the set value a, the force balance on the control piston 3 is disrupted, causing the control piston 3 and the first fuel control valve stem 8 to move upward. This reduces the flow area for the first fuel to enter the first fuel chamber 23, lowering the pressure in the first fuel chamber 23 and returning the pressure differential between the first and second fuel chambers 23 and 21 to the set value. If the reduced flow area for the first fuel to enter the first fuel chamber 23 prevents the pressure differential from reaching the set value, the control piston 3 and the first fuel control valve stem 8 continue to move upward until the sealing surface of the first fuel control valve stem 8 is again pressed against the housing 2. At the same time, when the pressure differential between the first fuel chamber 23 and the second fuel chamber 21 falls below the set value b, the force balance on the first fuel pressure relief valve stem 5 is disrupted, causing it to move upward. This now connects the first fuel chamber 23 with the first fuel pressure relief chamber 24, allowing the first fuel to be discharged from the first fuel pressure relief port 19. The pressure in the first fuel chamber 23 decreases until the pressure differential between the first fuel chamber 23 and the second fuel chamber 21 reaches the set value again. When the pressure differential between the first fuel chamber 23 and the second fuel chamber 21 exceeds the set value b, the first fuel pressure relief valve stem 5 presses against the sealing gasket 7. When the pressure differential between the first fuel chamber 23 and the second fuel chamber 21 exceeds the set value a, the control piston 3 and the first fuel control valve stem 8 move downward, disengaging the first fuel control valve stem 8 from the housing. This increases the flow area for the first fuel to enter the first fuel chamber 23. This now connects the first fuel chamber 23 with the first fuel inlet chamber 22, causing the pressure in the first fuel chamber 23 to rise until the pressure differential with the second fuel chamber 21 reaches the set value again.

[0036] It should be noted that the above specific implementation methods are only used to illustrate the technical solution of the utility model and are not limiting. Although the utility model is described in detail with reference to examples, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. A dual-fuel pressure regulating valve with a pressure relief structure, characterized in that: include: A housing (1), a second fuel inlet end cover (2), a control piston (3), a pressure relief valve stem (5), a limit assembly (4), a first elastic assembly (15), a second elastic assembly (16), a third elastic assembly (14), a first fuel control valve stem (8), and a plug (9); The control piston (3), the pressure relief valve stem (5), the limit assembly (4), the first elastic assembly (15), the second elastic assembly (16), the third elastic assembly (14), the first fuel control valve stem (8), and the plug (9) are all installed in the housing (1); The second fuel inlet end cover (2) is arranged at the upper end of the housing (1), the control piston (3) is slidably arranged in the housing (1) and the outer side wall of the control piston (3) is close to the inner side wall of the housing (1), and the first elastic component (15) is installed between the control piston (3) and the housing (1); The limit assembly (4) is mounted on the upper end of the control piston (3), the pressure relief valve stem (5) is slidably arranged inside the control piston (3) and the outer side wall of the pressure relief valve stem (5) is close to the inner side wall of the control piston (3), and the third elastic assembly (14) is mounted between the pressure relief valve stem (5) and the control piston (3); The plug (9) is arranged at the lower end of the housing (1), the second elastic component (16) is installed between the first fuel control valve stem (8) and the plug (9), and the upper end sealing surface of the first fuel control valve stem (8) abuts against the housing (1); A second fuel inlet (20) is provided on the second fuel inlet end cover (2), a second fuel cavity (21) is formed between the second fuel inlet end cover and the upper surface of the control piston (3), and the second fuel inlet (20) is in communication with the second fuel cavity (21); The lower surface of the control piston (3) and the housing (1) form a first fuel cavity (23); a side wall of the housing (1) is provided with a first fuel outlet (18); the first fuel cavity (23) is in communication with the first fuel outlet (18); A first fuel pressure relief chamber (24) is formed between the pressure relief valve stem (5) and the control piston (3); a first fuel pressure relief port (19) is provided on the side wall of the housing (1); the first fuel pressure relief port (19) is communicated with the first fuel pressure relief chamber (24); and the first fuel pressure relief chamber (24) is communicated with the first fuel chamber (23) when the third elastic component (14) is extended. A first fuel inlet cavity (22) is formed between the first fuel control valve stem (8) and the housing (1), a first fuel inlet (17) is provided on the side wall of the housing (1), the first fuel inlet (17) is communicated with the first fuel inlet cavity (22), and the first fuel inlet cavity (22) is communicated with the first fuel cavity (23) in a state where the second elastic component (16) is compressed and a state where the first elastic component (15) is compressed.

2. The dual-fuel pressure regulating valve with a pressure relief structure according to claim 1, wherein: A first sealing member (10) is provided between the second fuel inlet end cover (2) and the housing (1).

3. The dual-fuel pressure regulating valve with a pressure relief structure according to claim 1, wherein: A second sealing member (11) and a third sealing member (12) are provided between the control piston (3) and the housing (1); a pressure relief channel is provided on the control piston (3); the second sealing member (11) and the third sealing member (12) are respectively located on the upper and lower sides of the pressure relief channel.

4. The dual-fuel pressure regulating valve with a pressure relief structure according to claim 1, wherein: A fourth sealing member (13) is provided between the pressure relief valve stem (5) and the control piston (3), and the fourth sealing member (13) is used to separate the second fuel chamber (21) from the first fuel pressure relief chamber (24).

5. The dual-fuel pressure regulating valve with a pressure relief structure according to claim 1, wherein: The first elastic component (15), the second elastic component (16), and the third elastic component (14) are all springs.

6. The dual-fuel pressure regulating valve with a pressure relief structure according to claim 1, wherein: The limiting assembly (4) is a limiting nut, which is threadedly connected to the control piston (3).

7. The dual-fuel pressure regulating valve with a pressure relief structure according to claim 1, wherein: A communication channel is provided at the bottom end of the control piston (3), and the communication channel is used to connect the first fuel pressure relief chamber (24) with the first fuel chamber (23).

8. The dual-fuel pressure regulating valve with a pressure relief structure according to claim 1, wherein: A sealing gasket (7) is provided inside the control piston (3), the sealing gasket (7) is fixed by a fixing nut (6), and the sealing gasket (7) abuts against the sealing surface of the pressure relief valve stem (5).

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