Hydrogen pressure reducing valve group safety protection device and method

Abstract

The application discloses a hydrogen pressure reducing valve group safety protection device and method, and belongs to the field of pneumatic pressure reducing valve devices. The device comprises self-operated pressure reducing valves and overpressure regulation and control devices. In the direction of the gas flow, the self-operated pressure reducing valves are connected in series to realize multi-stage pressure reduction, and the overpressure regulation and control devices are connected to the pressure reduction outlet flow channel of the last-stage self-operated pressure reducing valve. The overpressure regulation and control devices comprise overpressure regulation and control valve bodies, overpressure regulation and control valve covers, first overpressure regulation and control actuators and second overpressure regulation and control actuators, can automatically adjust the pressure after the valve under overpressure conditions, and can realize overpressure early warning. The application can realize overpressure regulation, can realize stable adjustment of the pressure after the valve in large dynamic fluctuations, can prevent the occurrence of instantaneous overpressure locking conditions, and can prevent the loss of power of a fuel cell vehicle.

Description

Technical Field

[0001] This invention relates to the field of pneumatic pressure reducing valve devices, and more specifically to a safety protection device and method for a hydrogen pressure reducing valve assembly with fault locking function. Background Technology

[0002] Among hydrogen energy-related industries, hydrogen fuel cell vehicles have the most promising prospects. High-pressure hydrogen storage tanks (35-70 MPa) are the primary method for storing hydrogen in hydrogen fuel cell vehicles. The applicable pressure range for fuel cells is approximately 0.1-0.3 MPa. Ensuring stable pressure reduction under wide fluctuations in hydrogen inlet pressure is crucial for the safe and reliable operation of hydrogen fuel cells. The hydrogen pressure reducing valve plays a key role as a pressure reducing component. It creates a throttling effect when passing through a narrow cross-section, causing the hydrogen temperature to rise and the pressure to drop. The flow rate and outlet pressure of hydrogen can be adjusted by regulating the area of ​​the narrow cross-section, and multi-stage pressure reduction can achieve the pressure reduction to the applicable range of the fuel cell.

[0003] If the outlet pressure of the first or second stage easily rises on its own and exceeds a certain permissible value due to damage to the spring or diaphragm or other reasons, the overpressure can be classified into two types depending on the circumstances: minor overpressure and persistent overpressure.

[0004] Currently, the main method used to protect fuel cells from overpressure is to lock the secondary actuator, which can cause the fuel cell to lose power without warning. Therefore, it is necessary to make targeted modifications, including incorporating a small-amplitude internal pressure relief mechanism, a permanent secondary locking stop mechanism, and an overpressure sealing locking mechanism. Summary of the Invention

[0005] The purpose of this invention is to overcome the deficiencies in the prior art and provide a safety protection device and method for a hydrogen pressure reducing valve assembly. This device can achieve overpressure regulation, stably adjusting the downstream pressure under large dynamic fluctuations, preventing instantaneous overpressure locking conditions that could cause the fuel cell vehicle to lose power.

[0006] The specific technical solution adopted in this invention is as follows:

[0007] In a first aspect, the present invention provides a safety protection device for a hydrogen pressure reducing valve assembly, including a self-operated pressure reducing valve and an overpressure regulating device; along the airflow direction, several of the self-operated pressure reducing valves are connected in series to achieve multi-stage pressure reduction, and the pressure reducing outlet flow channel of the last stage self-operated pressure reducing valve is connected to the overpressure regulating device.

[0008] The overpressure control device includes an overpressure control valve body, an overpressure control valve cover, a first overpressure control actuator, and a second overpressure control actuator. The top of the overpressure control valve body is connected to the pressure-reducing outlet channel through an adjustment hole, and the first overpressure control actuator is installed inside. The first overpressure control actuator is a stepped columnar structure, including a first column with a smaller diameter and a second column with a larger diameter. The top of the first column is located in the adjustment hole and can extend into the pressure-reducing outlet channel through the adjustment hole to adjust the throttling area. A first overpressure control spring is sleeved on the outside of the second column, and a piezoelectric sensor is installed at the bottom. One end of the first overpressure control spring is fixed to the inner wall of the top of the overpressure control valve body, and the other end is fixed to the second column, providing vertical elastic force. A second sealing rubber gasket is provided between the first column and the second column to prevent the pressure-reducing outlet channel from communicating with the pressure-stabilizing chamber inside the overpressure control valve body. The pressure-stabilizing chamber is connected to the atmosphere through a pressure-stabilizing hole. Below the piezoelectric sensor... A second overpressure regulating actuator is provided, which can move vertically to provide an upward force to the first overpressure regulating actuator. The force contact area between the second overpressure regulating actuator and the piezoelectric sensor is larger than the area of ​​the top of the first column. The second overpressure regulating actuator is located in the overpressure regulating valve cover, which is sealed to the bottom of the overpressure regulating valve body and forms a feedback regulating chamber. The feedback regulating chamber is connected to the pressure reducing outlet channel through the overpressure regulating feedback channel, and the connection between the feedback regulating channel and the pressure reducing outlet channel is located in front of the regulating hole. A second overpressure regulating spring is provided at the bottom of the second overpressure regulating actuator, which can provide a vertical elastic force. One end of the second overpressure regulating spring is fixed to the bottom of the second overpressure regulating actuator, and the other end is fixed to the bottom of the overpressure regulating valve cover. A third sealing rubber gasket is provided between the second overpressure regulating actuator above the second overpressure regulating spring and the bottom of the overpressure regulating valve body, so that the pressure regulating chamber and the feedback regulating chamber are not connected to each other.

[0009] Preferably, the first column does not extend into the pressure relief outlet channel in its initial state.

[0010] Preferably, the top of the first column is a spherical structure with a diameter slightly smaller than that of the adjustment hole.

[0011] Preferably, the overpressure control device and all self-operated pressure reducing valves are housed in the same valve body.

[0012] Preferably, the first column is provided with external threads, and the second sealing rubber gasket is an annular structure with a central opening. The first column passes through the central opening and the inner ring of the second sealing rubber gasket is pressed and sealed to the top of the second column by the second pressure cap provided with internal threads. The second pressure cap is also provided with an annular pressure sleeve fixed to the overpressure regulating valve body. The first column extends into the regulating hole through the opening in the middle of the pressure sleeve, and the pressure sleeve presses and seals the outer ring of the second sealing rubber gasket to the inner top of the overpressure regulating valve body.

[0013] Preferably, a second valve disc is provided circumferentially extending from the bottom of the second column, and the first overpressure regulating spring is supported by the second valve disc and one end is fixed to the second valve disc.

[0014] Preferably, the bottom of the second overpressure control actuator is connected by a thread to a second pressure plate located above and a third pressure plate located below. The inner ring of the annular third sealing rubber gasket is pressed and sealed between the second pressure plate and the third pressure plate, and the outer ring of the third sealing rubber gasket is pressed and sealed to the bottom surface of the overpressure control valve body by a pressure ring.

[0015] Preferably, the overpressure regulating valve cover is sealed to the bottom of the overpressure regulating valve body via an annular gasket.

[0016] Secondly, the present invention provides a pressure reduction method using the hydrogen pressure reducing valve assembly safety protection device described in any of the first aspects, as follows:

[0017] During normal operation, the gas pressure flowing out from the final stage self-regulating pressure reducing valve is less than the set value; the first column does not extend into the pressure reducing outlet channel, and the gas flows out from the pressure reducing outlet channel after being successively reduced by the multi-stage self-regulating pressure reducing valves.

[0018] During abnormal overpressure operation, the gas pressure flowing out from the final stage self-regulating pressure reducing valve is greater than or equal to the set value. Part of the gas in the pressure reducing outlet channel enters the feedback regulating chamber through the feedback regulating channel and exerts an upward force on the second overpressure regulating actuator. Since the pressure stabilizing chamber is connected to the atmosphere, the gas pressure in the pressure stabilizing chamber is lower than the gas pressure in the feedback regulating chamber. The second overpressure regulating actuator gradually moves upward and squeezes the piezoelectric sensor, causing the piezoelectric sensor to trigger an abnormal alarm. Because the contact area between the second overpressure regulating actuator and the piezoelectric sensor is greater than the area of ​​the top of the first column, the second overpressure regulating actuator further drives the first overpressure regulating actuator upward through the piezoelectric sensor, causing the top of the first column to extend into the pressure reducing outlet channel through the regulating hole. Pressure reduction is achieved by changing the throttling area in the pressure reducing outlet channel.

[0019] Preferably, the self-operated pressure reducing valve includes a primary self-operated pressure reducing valve and a secondary self-operated pressure reducing valve arranged along the airflow direction; under normal operation, the primary self-operated pressure reducing valve can reduce the gas pressure to 1.5-2.5 MPa, and the secondary self-operated pressure reducing valve can reduce the gas pressure to 0.1-0.3 MPa.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) The present invention can achieve overpressure regulation, and can stabilize the pressure after the valve in large dynamic fluctuations, preventing instantaneous overpressure lock-up conditions that would cause the fuel cell vehicle to lose power.

[0022] (2) This invention activates multi-stage (e.g., three-stage) pressure reduction under overpressure conditions and shuts it off under extreme overpressure conditions. Under overpressure conditions, it can automatically identify overpressure and display error messages. Attached Figure Description

[0023] Figure 1 Schematic diagram of the main valve body structure;

[0024] Figure 2 This is a schematic diagram of the overall structure of the device;

[0025] Figure 3 This is a schematic diagram of a two-stage pressure reducing valve;

[0026] Figure 4 This is a schematic diagram of the overpressure control device;

[0027] In the diagram: 1. First-stage pressure reducing valve seat; 2. First-stage pressure reducing valve downstream flow channel; 3. Second-stage pressure reducing valve seat; 4. Pressure reducing outlet flow channel; 5. Overpressure regulation feedback flow channel; 6. Pressure stabilizing chamber; 7. Shaft seal; I. First-stage pressure reducing valve core; II. Second-stage pressure reducing valve core; III. Overpressure regulation device; 8. First-stage pressure reducing valve piston; 9. Sealing gasket; 10. First and second stage springs; 11. Second stage springs; 12. First-stage pressure reducing valve core seat; 13. Second-stage pressure reducing valve piston; 14. First and second stage springs; 15. Second-stage actuator; 16. Second-stage pressure reducing valve core seat; 17. First gland; 18. First sealing rubber gasket. 9. First pressure plate; 20. Secondary spring; 21. Secondary pressure reducing valve cover; 22. Adjusting screw; 23. Pressure relief hole; 24. First valve disc; 25. Secondary feedback flow channel; 26. First overpressure regulating actuator; 27. Second sealing rubber gasket; 28. Second pressure cover; 29. ​​Pressure sleeve; 30. First overpressure regulating spring; 31. Pressure stabilizing hole; 32. Piezoelectric sensor; 33. Second pressure plate; 34. Second overpressure regulating actuator; 35. Third sealing rubber gasket; 36. Pressure ring; 37. Annular gasket; 38. Overpressure regulating valve cover; 39. Third pressure plate; 40. Second overpressure regulating spring. Detailed Implementation

[0028] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly, provided that there is no mutual conflict.

[0029] This invention provides a safety protection device for a hydrogen pressure reducing valve assembly, mainly comprising an overpressure regulating device III and multiple self-operated pressure reducing valves. Along the gas flow direction, the multiple self-operated pressure reducing valves are connected in series to achieve multi-stage pressure reduction. The overpressure regulating device III is connected to the pressure reducing outlet flow channel 4 of the final-stage self-operated pressure reducing valve. The specific structure and connection method are described below using an example of a hydrogen pressure reducing valve assembly safety protection device with two self-operated pressure reducing valves: a primary self-operated pressure reducing valve and a secondary self-operated pressure reducing valve.

[0030] In this embodiment, the primary self-regulating pressure reducing valve, the secondary self-regulating pressure reducing valve, and the overpressure regulating device III can be mounted on the same valve body, such as... Figure 1 As shown. The left side of the valve body has an axially penetrating stepped cavity, serving as the primary pressure-reducing valve seat 1; the middle side of the valve body has an axially penetrating stepped cavity, serving as the secondary pressure-reducing valve seat 3; the right side of the valve body has a stepped groove cavity, serving as the pressure-stabilizing chamber 6. The primary pressure-reducing valve core I and the secondary pressure-reducing valve core II are respectively installed in the valve body via the primary pressure-reducing valve seat 1 and the secondary pressure-reducing valve seat 3, as shown. Figure 2 As shown. In this embodiment, both the primary self-operated pressure reducing valve and the secondary self-operated pressure reducing valve can adopt existing self-operated pressure reducing valve structures. The structures of the primary self-operated pressure reducing valve and the secondary self-operated pressure reducing valve will be briefly described below.

[0031] like Figure 2 As shown, the primary pressure reducing valve core is used to connect to an external hydrogen source and perform the first-stage pressure reduction on the input hydrogen, which is then introduced into the downstream flow channel 2 of the primary pressure reducing valve. The primary pressure reducing valve core mainly includes a primary pressure reducing valve piston 8, a sealing gasket 9, a first-stage spring 10, a second-stage spring 11, and a primary pressure reducing valve core seat 12. The primary pressure reducing valve piston 8 and the primary pressure reducing valve core seat 12 are fixedly installed at the openings at both ends of the primary pressure reducing valve seat 1, and the primary pressure reducing valve core seat 12 has a through inlet flow channel. The primary actuator is located between the primary pressure reducing valve piston 8 and the primary pressure reducing valve core seat 12, and the tip of the primary actuator has a conical structure to achieve primary pressure reduction. The first-stage spring 10 is located between the primary actuator and the primary pressure reducing valve piston 8, and the second-stage spring 11 is located between the primary actuator and the primary pressure reducing valve core seat 12.

[0032] like Figure 3The diagram shows the structure of a two-stage self-operated pressure reducing valve. This valve connects to the downstream flow channel 2 of the first-stage pressure reducing valve and performs secondary pressure reduction on the hydrogen gas in the downstream flow channel 2 before outputting it to the pressure reducing outlet flow channel. It can also be locked under extreme overpressure conditions. The two-stage self-operated pressure reducing valve mainly includes a two-stage pressure reducing valve piston 13, first and second stage springs 14, a two-stage actuator 15, a two-stage pressure reducing valve core seat 16, a first pressure cap 17, a first sealing rubber gasket 18, a first pressure plate 19, a second and second stage spring 20, a two-stage pressure reducing valve cover 21, an adjusting screw 22, a pressure relief hole 23, a first valve disc 24, and a two-stage feedback flow channel 25. The secondary pressure reducing valve piston 13 and the secondary pressure reducing valve core seat 16 are fixedly installed at the two end openings of the secondary pressure reducing valve seat 3. The secondary pressure reducing valve core seat 16 has a through channel. The secondary actuator 15 has a channel passing through the secondary pressure reducing valve core seat 16, and the upper part of the secondary actuator 15 and the secondary pressure reducing valve core seat 16 together form a secondary throttling area. The lower end of the secondary actuator 15 has an external thread, which is connected to the internal threads of the first pressure cover 17 and the first pressure plate 19 through the external thread. The first sealing rubber gasket 18 has a through hole in the middle. The first pressure cover 17 and The first pressure plate 19 clamps and seals the first sealing rubber gasket 18 through the through hole of the first sealing rubber gasket 18; the second secondary spring 20 is disposed between the first pressure plate 19 and the first valve plate 24; the secondary pressure reducing valve cover 21 is cylindrical and has a through hole in the middle that mates with the adjusting screw 22; the secondary pressure reducing valve cover 21 presses against the annular first sealing rubber gasket 18 at the valve body; the pressure relief hole 23 is disposed on the secondary pressure reducing valve cover 21; the top of the adjusting screw 22 is disposed in the groove of the first valve plate 24 and is used to adjust the preload of the second secondary spring 20.

[0033] like Figure 4 As shown, the overpressure control device III mainly includes an overpressure control valve body, an overpressure control valve cover 38, a first overpressure control actuator 26, and a second overpressure control actuator 34. The top of the overpressure control valve body is connected to the pressure reducing outlet channel 4 through an adjustment hole, and the first overpressure control actuator 26 is installed inside. The first overpressure control actuator 26 is a stepped columnar structure, including a first column with a smaller diameter and a second column with a larger diameter. The top of the first column is located in the adjustment hole and can move vertically up and down under the limiting action of the adjustment hole. It can extend into the pressure reducing outlet channel 4 through the adjustment hole to adjust the throttling area of ​​the pressure reducing outlet channel 4. A first overpressure control spring 30 is sleeved on the outside of the second column, and a piezoelectric sensor 32 is installed at the bottom. One end of the first overpressure control spring 30 is fixed to the inner wall of the top of the overpressure control valve body, and the other end is fixed to the second column, providing a vertical elastic force. The first column and the second column are connected by a second sealing rubber gasket 27 so that the pressure reducing outlet flow channel 4 and the pressure stabilizing chamber 6 in the overpressure regulating valve body are not connected. The pressure stabilizing chamber 6 is connected to the atmosphere through the pressure stabilizing hole 31.

[0034] In this embodiment, the first column does not initially extend into the pressure-reducing outlet channel 4 and therefore does not have a throttling effect on the pressure-reducing outlet channel 4. The top of the first column can be configured as a spherical structure with a diameter slightly smaller than the diameter of the adjustment hole, so that the first column can move within the adjustment hole. A second valve disc extends circumferentially from the bottom of the second column, and the first overpressure regulating spring 30 is supported by the second valve disc and fixed at one end to the second valve disc. To prevent the pressure-reducing outlet flow channel 4 from communicating with the pressure-stabilizing chamber 6 within the overpressure control valve body, the second sealing rubber gasket 27 can be fixed and sealed in the following manner: The first column has external threads, and the second sealing rubber gasket 27 is an annular structure with a central opening. The first column passes through the central opening, and the inner ring of the second sealing rubber gasket 27 is pressed and sealed to the top of the second column by the second pressure cap 28, which has internal threads. The second pressure cap 28 also has an annular pressure sleeve 29 fixed to the overpressure control valve body. The first column extends into the adjustment hole through the opening in the middle of the pressure sleeve 29, and the pressure sleeve 29 presses and seals the outer ring of the second sealing rubber gasket 27 to the inner top of the overpressure control valve body. Specifically, the second pressure cap 28 is connected to the external threads of the first overpressure control actuator 26 via its internal threads, rotates to the bottom of the boss of the first overpressure control actuator 26, and presses the second sealing rubber gasket 27. That is, the through hole of the second sealing rubber gasket 27 passes through the bottom of the boss of the first overpressure control actuator 26 and is clamped by the second pressure cap 28. The piezoelectric sensor 32 is connected to the signal line, which passes through the voltage regulator hole 31 to provide an overpressure warning.

[0035] Below the piezoelectric sensor 32 of this device is a second overpressure control actuator 34 that can move vertically. The second overpressure control actuator 34 can provide an upward force to the first overpressure control actuator 26 through vertical movement. The force-bearing contact area between the second overpressure control actuator 34 and the piezoelectric sensor 32 should be larger than the area of ​​the top of the first column. The second overpressure control actuator 34 is located in the overpressure control valve cover 38, which is sealed to the bottom of the overpressure control valve body and forms a feedback adjustment chamber. The feedback adjustment chamber is connected to the pressure reduction outlet channel 4 through the overpressure control feedback channel 5, and the connection between the feedback adjustment channel and the pressure reduction outlet channel 4 is located in front of the adjustment hole. At the bottom of the second overpressure control actuator 34 is a second overpressure control spring 40 that can provide vertical elastic force. One end of the second overpressure control spring 40 is fixed to the bottom of the second overpressure control actuator 34, and the other end is fixed to the bottom of the overpressure control valve cover 38. A third sealing rubber gasket 35 is provided between the second overpressure regulating actuator 34 located above the second overpressure regulating spring 40 and the bottom of the overpressure regulating valve body, so that the pressure stabilizing chamber 6 and the feedback regulating chamber are not connected to each other.

[0036] In this embodiment, to prevent the pressure stabilizing chamber 6 from communicating with the feedback regulating chamber, the bottom of the second overpressure regulating actuator 34 is threadedly connected to a second pressure plate 33 located above and a third pressure plate 39 located below. The inner ring of the annular third sealing rubber gasket 35 is pressed and sealed between the second pressure plate 33 and the third pressure plate 39, and the outer ring of the third sealing rubber gasket 35 is pressed and sealed to the bottom surface of the overpressure regulating valve body by a pressure ring. The overpressure regulating valve cover 38 can be sealed to the bottom of the overpressure regulating valve body by an annular gasket 37.

[0037] In practical applications, the pressure sleeve 29 can be fixed to the valve body by means of interference fit or other methods. The adjustment hole at the top of the overpressure regulating valve body has a diameter similar to that of the pressure reducing outlet flow channel 4.

[0038] The pressure reduction method using the aforementioned hydrogen pressure reducing valve assembly safety protection device is as follows:

[0039] During normal operation, the gas pressure flowing out from the final stage self-regulating pressure reducing valve is less than the set value. The first column does not extend into the pressure reducing outlet channel 4. The gas is pressure reduced sequentially by the first-stage and second-stage self-regulating pressure reducing valves before flowing out from the pressure reducing outlet channel 4.

[0040] During abnormal overpressure operation, the gas pressure flowing out from the final stage self-regulating pressure reducing valve is greater than or equal to the set value. Part of the gas in the pressure reducing outlet channel 4 enters the feedback regulating chamber through the feedback regulating channel, exerting an upward force on the second overpressure regulating actuator 34. Since the pressure stabilizing chamber 6 is connected to the atmosphere, the gas pressure inside the pressure stabilizing chamber 6 is lower than the gas pressure inside the feedback regulating chamber. The second overpressure regulating actuator 34 gradually moves upward and squeezes the piezoelectric sensor 32, triggering an abnormal alarm. Because the contact area between the second overpressure regulating actuator 34 and the piezoelectric sensor 32 is larger than the area of ​​the top of the first column, the second overpressure regulating actuator 34, through the piezoelectric sensor 32, further drives the first overpressure regulating actuator 26 upward, causing the top of the first column to extend into the pressure reducing outlet channel 4 through the regulating hole. Pressure reduction is achieved by changing the throttling area in the pressure reducing outlet channel 4.

[0041] In this embodiment, taking a hydrogen pressure reducing valve group safety protection device with two self-operated pressure reducing valves as an example, the pressure reducing method is as follows:

[0042] S1. During normal operation, hydrogen gas is reduced to approximately 2 MPa via a primary self-regulating pressure reducing valve, and then further reduced to 0.1–0.3 MPa via a secondary self-regulating pressure reducing valve. At this time, the pressure range of the feedback regulating chamber is consistent with the pressure at the outlet of the secondary self-regulating pressure reducing valve, which is 0.1–0.3 MPa. During this operation, the movement of the second overpressure regulating actuator 34 will not compress the piezoelectric sensor.

[0043] S2. During abnormal overpressure operation, an overpressure condition will occur after the secondary self-regulating pressure reducing valve. At this time, the pressure in the feedback regulating chamber exceeds 0.3MPa. As the pressure increases, the upward pressure on the second overpressure regulating actuator 34 increases. The pressure in the pressure stabilizing chamber 6 at the top of the second overpressure regulating actuator 34 is connected to the atmosphere, and the pressure is atmospheric pressure of 0.1MPa. When the pressure in the feedback regulating chamber exceeds 0.3MPa, the second overpressure regulating actuator 34 begins to squeeze the pressure sensor and issues an abnormal alarm.

[0044] S3. Since the high-pressure side force-bearing area on the first overpressure control actuator 26 is small and the high-pressure side force-bearing area on the second overpressure control actuator 34 is large, exceeding 0.3MPa, when the first overpressure control actuator 26 and the second overpressure control actuator 34 come into contact, the second overpressure control actuator 34 further drives the first overpressure control actuator 26 to move upward. The top of the first overpressure control actuator 26 extends out of the pressure reduction outlet channel 4, generating throttling and pressure reduction, thereby reducing the hydrogen gas at the pressure reduction outlet channel 4 to a pressure range of 0.1 to 0.3MPa.

[0045] S4. When an abnormal alarm occurs, due to the throttling effect of the first overpressure control actuator 26, the electric vehicle will not lose power, making it easier for the owner to find a suitable area to park and avoid danger.

[0046] In the device of this invention, the primary self-regulating pressure reducing valve performs the main throttling and pressure reduction function, carrying out the first stage of pressure reduction; the secondary self-regulating pressure reducing valve further reduces the pressure of the hydrogen after the primary pressure reduction; the overpressure control device can automatically adjust the downstream pressure under overpressure conditions and provide overpressure warning. This invention can achieve overpressure control, and can stably regulate the downstream pressure under large dynamic pressure fluctuations, preventing the hydrogen pressure reducing valve assembly from experiencing instantaneous overpressure lock-up, and ultimately preventing the fuel cell vehicle from instantly losing power.

[0047] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained through equivalent substitution or transformation fall within the protection scope of the present invention.

Claims

1. A safety protection device for a hydrogen pressure reducing valve assembly, characterized in that, It includes a self-operated pressure reducing valve and an overpressure control device (III); along the airflow direction, several of the self-operated pressure reducing valves are connected in series to achieve multi-stage pressure reduction, and the pressure reducing outlet flow channel (4) of the last stage self-operated pressure reducing valve is connected to the overpressure control device (III). The overpressure control device (III) includes an overpressure control valve body, an overpressure control valve cover (38), a first overpressure control actuator (26), and a second overpressure control actuator (34). The top of the overpressure control valve body is connected to the pressure reducing outlet channel (4) through an adjustment hole, and the first overpressure control actuator (26) is provided inside. The first overpressure control actuator (26) is a stepped columnar structure, including a first column with a smaller diameter and a second column with a larger diameter. The top of the first column is located in the adjustment hole and can extend into the pressure reducing outlet channel (4) through the adjustment hole to adjust the pressure. Throttling area; the second column is fitted with a first overpressure regulating spring (30) and a piezoelectric sensor (32) at the bottom; one end of the first overpressure regulating spring (30) is fixed to the inner wall of the top of the overpressure regulating valve body, and the other end is fixed to the second column, which can provide vertical elastic force; the first column and the second column are connected by a second sealing rubber gasket (27) so that the pressure reducing outlet flow channel (4) and the pressure stabilizing chamber (6) in the overpressure regulating valve body are not connected to each other, and the pressure stabilizing chamber (6) is connected to the atmosphere through the pressure stabilizing hole (31); the piezoelectric sensor (32) is provided below it with a function that can provide vertical elastic force; A second overpressure control actuator (34) moves vertically to provide an upward force to the first overpressure control actuator (26). The force contact area between the second overpressure control actuator (34) and the piezoelectric sensor (32) is larger than the area of ​​the top of the first column. The second overpressure control actuator (34) is located in the overpressure control valve cover (38), which is sealed to the bottom of the overpressure control valve body and forms a feedback adjustment chamber. The feedback adjustment chamber is connected to the pressure reduction outlet channel (4) through the overpressure control feedback channel (5), and the feedback adjustment channel is connected to the pressure reduction outlet channel. (4) The connection point is located in front of the adjustment hole; the bottom of the second overpressure control actuator (34) is provided with a second overpressure control spring (40) that can provide vertical elastic force; one end of the second overpressure control spring (40) is fixed to the bottom of the second overpressure control actuator (34), and the other end is fixed to the bottom of the overpressure control valve cover (38); a third sealing rubber gasket (35) is provided between the second overpressure control actuator (34) located above the second overpressure control spring (40) and the bottom of the overpressure control valve body, so that the pressure stabilizing chamber (6) and the feedback adjustment chamber are not connected to each other.

2. The safety protection device for a hydrogen pressure reducing valve assembly according to claim 1, characterized in that, The first column does not extend into the pressure relief outlet channel (4) in its initial state.

3. The safety protection device for a hydrogen pressure reducing valve assembly according to claim 1, characterized in that, The top of the first column is a spherical structure with a diameter slightly smaller than that of the adjustment hole.

4. The safety protection device for a hydrogen pressure reducing valve assembly according to claim 1, characterized in that, The overpressure control device (III) and all self-operated pressure reducing valves are located in the same valve body.

5. A safety protection device for a hydrogen pressure reducing valve assembly according to claim 1, characterized in that, The first column is provided with external threads, and the second sealing rubber gasket (27) is an annular structure with a central opening. The first column passes through the central opening and the inner ring of the second sealing rubber gasket (27) is pressed and sealed to the top of the second column by the second pressure cap (28) which is provided with internal threads. The second pressure cap (28) is also provided with an annular pressure sleeve (29) fixed on the overpressure regulating valve body. The first column extends into the regulating hole through the opening in the middle of the pressure sleeve (29). The pressure sleeve (29) presses and seals the outer ring of the second sealing rubber gasket (27) to the inner top of the overpressure regulating valve body.

6. The safety protection device for a hydrogen pressure reducing valve assembly according to claim 1, characterized in that, The second column has a second valve disc extending circumferentially from the bottom. The first overpressure regulating spring (30) is supported by the second valve disc and one end is fixed to the second valve disc.

7. A safety protection device for a hydrogen pressure reducing valve assembly according to claim 1, characterized in that, The second overpressure control actuator (34) has a second pressure plate (33) located above and a third pressure plate (39) located below connected by threads at the bottom. The inner ring of the annular third sealing rubber gasket (35) is pressed and sealed between the second pressure plate (33) and the third pressure plate (39). The outer ring of the third sealing rubber gasket (35) is pressed and sealed to the bottom surface of the overpressure control valve body by a pressure ring.

8. A safety protection device for a hydrogen pressure reducing valve assembly according to claim 1, characterized in that, The overpressure control valve cover (38) is sealed to the bottom of the overpressure control valve body via an annular gasket (37).

9. A method for reducing pressure using the safety protection device of the hydrogen pressure reducing valve assembly according to any one of claims 1 to 8, characterized in that, Specifically as follows: During normal operation, the gas pressure flowing out from the final stage self-regulating pressure reducing valve is less than the set value; the first column does not extend into the pressure reducing outlet channel (4), and the gas flows out from the pressure reducing outlet channel (4) after being depressurized sequentially by the multi-stage self-regulating pressure reducing valve. When operating under abnormal overpressure, the gas pressure flowing out from the final stage self-regulating pressure reducing valve is greater than or equal to the set value; part of the gas in the pressure reducing outlet channel (4) enters the feedback regulating chamber through the feedback regulating channel and exerts an upward force on the second overpressure regulating actuator (34); since the pressure stabilizing chamber (6) is connected to the atmosphere, the gas pressure in the pressure stabilizing chamber (6) is lower than the gas pressure in the feedback regulating chamber, the second overpressure regulating actuator (34) gradually moves upward and squeezes the piezoelectric sensor (32), and the piezoelectric sensor (32) alarms abnormally; since the contact area between the second overpressure regulating actuator (34) and the piezoelectric sensor (32) is greater than the area of ​​the top of the first column, the second overpressure regulating actuator (34) further drives the first overpressure regulating actuator (26) to move upward through the piezoelectric sensor (32), so that the top of the first column extends into the pressure reducing outlet channel (4) through the regulating hole, and pressure reduction is achieved by changing the throttling area in the pressure reducing outlet channel (4).

10. The decompression method according to claim 9, characterized in that, The self-operated pressure reducing valve includes a primary self-operated pressure reducing valve and a secondary self-operated pressure reducing valve arranged along the airflow direction; under normal operation, the primary self-operated pressure reducing valve can reduce the gas pressure to 1.5-2.5 MPa, and the secondary self-operated pressure reducing valve can reduce the gas pressure to 0.1-0.3 MPa.

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