Dual fuel constant pressure differential valve and pressure differential constant regulating method thereof

Abstract

The application discloses a kind of dual fuel constant differential pressure valve and its differential pressure constant regulating method, belong to fluid pressure control technical field, the constant differential pressure valve includes outer shell, its inside is formed with first fuel high pressure chamber, first fuel low pressure chamber and second fuel high pressure chamber, first position is equipped in outer shell;Valve sealing assembly is set in outer shell, valve sealing assembly can be axially moved;Plunger assembly is set in outer shell, the bottom end of plunger assembly is used to bear the real-time pressure in second fuel high pressure chamber to axially move, the top end of plunger assembly is in abutment with valve sealing assembly;Spring is arranged in first fuel high pressure chamber, spring applies pre-tightening force to valve sealing assembly, and a kind of differential pressure constant regulating method of constant differential pressure valve is also disclosed.The application does not need external energy, sensor or controller, only by mechanical structure and fluid mechanics principle, realizes the independent, reliable and constant control of two kinds of independent fluid pressure difference that can be set.

Description

Technical Field

[0001] This invention belongs to the field of fluid pressure control technology, and particularly relates to a dual-fuel constant differential pressure valve and its differential pressure constant regulation method. Background Technology

[0002] In the field of dual-fuel compression ignition engine technology, ensuring a specific and stable pressure difference between the two fuels at the injection point is crucial for achieving precise injection and efficient combustion in order to realize a high-efficiency combustion mode. Existing dual-fuel fuel supply systems typically rely on two independent electronic pressure regulating valves (EPRs) to regulate the pressure of the two fuels separately, and use pressure sensors and electronic control units (ECUs) for complex closed-loop feedback control.

[0003] However, this electronic control method has many inherent drawbacks: First, the system is complex, requiring additional sensors, wiring harnesses, and control modules, resulting in high costs; second, the response speed of electronic components is limited by the electronic control cycle, making it difficult to achieve instantaneous and accurate tracking of pressure differences under rapid changes in engine load or transient conditions, easily leading to response lag; in addition, in the harsh environment of high temperature, high pressure, and strong vibration in the engine compartment, the long-term operational reliability of electronic components faces severe challenges, and they are susceptible to electromagnetic interference, leading to decreased control accuracy or failure.

[0004] Therefore, there is an urgent need to design a dual-fuel constant differential pressure valve and its differential pressure constant regulation method to solve the problems mentioned above. Summary of the Invention

[0005] The purpose of this invention is to provide a dual-fuel constant differential pressure valve and its differential pressure constant regulation method. It has the advantages of using direct feedback from the mechanical structure to automatically respond to fuel pressure fluctuations and adjust the discharge in real time to maintain a constant differential pressure between the two fuels. It solves the problems of complex structure, slow response and poor reliability of constant differential pressure valves that rely on electronic control systems in the prior art.

[0006] To achieve the above objectives, the specific technical solution of the present invention, a dual-fuel constant differential pressure valve and its differential pressure constant adjustment method, is as follows: A dual-fuel constant pressure differential valve, comprising: The outer casing has a first high-pressure fuel chamber, a first low-pressure fuel chamber and a second high-pressure fuel chamber inside it, and a first position is provided inside the outer casing. A valve sealing assembly is disposed within the housing. The valve sealing assembly is axially movable. When the valve sealing assembly moves to the first position, it cuts off the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber. When the valve sealing assembly is separated from the first position, it connects the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber, and the pressure in the first high-pressure fuel chamber is released through the first low-pressure fuel chamber. A plunger assembly is disposed within the housing. The bottom end of the plunger assembly is used to withstand the real-time pressure in the second fuel high-pressure chamber to move axially, and the top end of the plunger assembly abuts against the valve sealing assembly. A spring is located in the first high-pressure fuel chamber, and the spring applies a preload force to the valve sealing assembly; When the force exerted by the second high-pressure fuel chamber on the bottom of the plunger assembly is equal to the sum of the force exerted by the first high-pressure fuel chamber on the top of the valve sealing assembly and the preload of the spring, the plunger assembly and the valve sealing assembly are in a state of force equilibrium. The valve sealing assembly is located at the critical position where the first high-pressure fuel chamber and the first low-pressure fuel chamber are connected, so as to maintain a constant pressure difference between the first high-pressure fuel chamber and the second high-pressure fuel chamber. Furthermore, the plunger assembly is configured to drive the valve sealing assembly to displace in response to pressure fluctuations in the second fuel high-pressure chamber, thereby adjusting the discharge flow rate of the first fuel high-pressure chamber by changing the opening of the fluid passage, so that the pressure in the first fuel high-pressure chamber follows the pressure changes in the second fuel high-pressure chamber and maintains a constant pressure difference.

[0007] Furthermore, when the pressure rise in the second high-pressure fuel chamber breaks the force balance, the plunger assembly pushes the valve sealing assembly to move closer to the first position, thereby reducing the opening of the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber, reducing the leakage flow of the first high-pressure fuel chamber and increasing the pressure in the first high-pressure fuel chamber until the force balance is restored.

[0008] Furthermore, when the pressure in the second high-pressure fuel chamber decreases and breaks the force balance, the pressure in the first high-pressure fuel chamber and the preload of the spring push the valve sealing assembly to move away from the first position, thereby increasing the opening of the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber, increasing the discharge flow of the first high-pressure fuel chamber and decreasing the pressure in the first high-pressure fuel chamber until the force balance is restored.

[0009] Furthermore, the first high-pressure fuel chamber is provided with a first high-pressure fuel inlet and a first high-pressure fuel outlet. First fuel is introduced through the first high-pressure fuel inlet and the first fuel with adjusted pressure is output through the first high-pressure fuel outlet. The first low-pressure fuel chamber is provided with a first low-pressure fuel outlet. When the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber is connected, the first high-pressure fuel chamber discharges the first fuel that has been drained through the fluid passage through the first low-pressure fuel outlet.

[0010] Furthermore, the second fuel high-pressure chamber is provided with a second fuel high-pressure inlet and a second fuel high-pressure outlet. Second fuel is introduced through the second fuel high-pressure inlet and the second fuel with adjusted pressure is output through the second fuel high-pressure outlet.

[0011] Furthermore, the valve sealing assembly includes a valve seat disposed between the first high-pressure fuel chamber and the first low-pressure fuel chamber. The valve seat has a connecting passage and a ball valve is provided on the valve seat. The ball valve abuts against the top of the plunger assembly and can move axially. When the ball valve moves to the first position, the ball valve blocks the connecting passage of the valve seat to cut off the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber. When the ball valve is separated from the first position, the connecting passage between the ball valve and the valve seat is separated, connecting the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber. The opening degree of the fluid passage is changed by changing the distance between the ball valve and the connecting passage of the valve seat.

[0012] Furthermore, a push rod is fixedly connected to the ball valve. The push rod extends through the connecting passage into the first fuel high-pressure chamber, and one end of the push rod extending into the first fuel high-pressure chamber is fixedly connected to a spring.

[0013] Furthermore, a limiting part is provided below the valve seat, and a limiting groove is opened in the limiting part, so that the ball valve can slide along the limiting groove.

[0014] Furthermore, the plunger assembly includes a plunger sleeve disposed within the outer casing, a plunger body disposed within the plunger sleeve, the plunger body being slidable relative to the plunger sleeve, the bottom end of the plunger body being located within the second fuel high-pressure chamber to receive the real-time pressure of the second fuel high-pressure chamber, and the top end of the plunger body abutting against the ball valve.

[0015] A method for maintaining a constant differential pressure in a constant differential pressure valve, comprising the following steps: S1. The second fuel enters the second fuel high-pressure chamber, and the pressure acts on the bottom end of the plunger assembly, pushing the plunger assembly and valve sealing assembly to move upward to the first position, so that the valve sealing assembly is pressed to close the fluid passage between the first fuel high-pressure chamber and the first fuel low-pressure chamber. S2. The first fuel enters the first fuel high-pressure chamber, and the pressure acts on the top of the valve sealing assembly; S3. When the force exerted by the second high-pressure fuel chamber on the bottom end of the plunger assembly is less than the sum of the force exerted by the first high-pressure fuel chamber on the top end of the valve sealing assembly and the preload force of the spring, the valve sealing assembly is pushed open and separated from the first position. The pressure in the first high-pressure fuel chamber is released through the first low-pressure fuel chamber, resulting in a decrease in the pressure in the first high-pressure fuel chamber. S4. As the pressure in the first high-pressure fuel chamber decreases, when the force exerted by the second high-pressure fuel chamber on the bottom of the plunger assembly equals the sum of the force exerted by the first high-pressure fuel chamber on the top of the valve sealing assembly and the preload of the spring, the valve sealing assembly is in a critical position of dynamic equilibrium, maintaining a constant pressure difference.

[0016] The present invention has the following advantages: The present invention does not require external energy, sensors or controllers. It achieves autonomous, reliable and settable constant control of the pressure difference between two independent fluids through mechanical structure and fluid mechanics principles. It can respond instantly to fuel pressure fluctuations and automatically adjust the discharge flow rate so that the controlled fuel pressure follows the change of the reference fuel pressure, thereby stabilizing the pressure difference between the two at a preset value. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the constant differential pressure valve of the present invention; Figure 2 This is a schematic diagram of the valve sealing assembly and the limiting part of the present invention; Figure 3 This is a schematic diagram of the plunger assembly and limiting part of the present invention; Explanation of markings in the diagram: 1. Outer shell; 11. First shell; 12. Second shell; 13. Locating pin; 14. First high-pressure fuel chamber; 141. First high-pressure fuel inlet; 142. First high-pressure fuel outlet; 15. First low-pressure fuel chamber; 151. First low-pressure fuel outlet; 16. Second high-pressure fuel chamber; 161. Second high-pressure fuel inlet; 162. Second high-pressure fuel outlet; 17. First plug; 18. Second plug; 2. Valve sealing assembly; 21. Valve seat; 22. Connecting passage; 23. Ball valve; 24. Push rod; 3. Piston assembly; 31. Piston sleeve; 32. Piston body; 4. Limiting part; 41. Limiting groove; 5. Spring; 7. Low-pressure sealing ring. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0020] The following is a reference to the appendix. Figure 1 To be continued Figure 3 This invention describes a dual-fuel constant differential pressure valve and a method for regulating the constant differential pressure.

[0021] A dual-fuel constant pressure differential valve includes a housing 1, a valve sealing assembly 2, a plunger assembly 3, and a spring 5. The housing 1 contains a first high-pressure fuel chamber 14, a first low-pressure fuel chamber 15, and a second high-pressure fuel chamber 16. A first position is provided within the housing 1. The valve sealing assembly 2 is disposed within the housing 1 and is axially movable. When the valve sealing assembly 2 moves to the first position, it cuts off the fluid passage between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15. When the valve sealing assembly 2 is separated from the first position, it connects the fluid passage between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15, allowing the pressure in the first high-pressure fuel chamber 14 to be released through the first low-pressure fuel chamber 15. The plunger assembly 3 is disposed within the housing 1. The bottom end of the plunger assembly 3 is used to withstand the real-time pressure in the second high-pressure fuel chamber 16 for axial movement, and the top end of the plunger assembly 3 abuts against the valve sealing assembly 2. The spring 5 is disposed within the first high-pressure fuel chamber 14 and applies a preload force to the valve sealing assembly 2.

[0022] The first position is a specific position preset inside the outer casing 1. When the valve sealing assembly 2 moves axially to this position, it will completely block the fluid passage between the first fuel high-pressure chamber 14 and the first fuel low-pressure chamber 15, thereby cutting off the passage.

[0023] The outer casing 1 includes a first casing 11 and a second casing 12. The first casing 11 and the second casing 12 are fixedly connected by a positioning pin 13. The positioning pin 13 ensures that the first casing 11 and the second casing 12 are precisely aligned, ensuring that the internal flow channels are unobstructed and the components are aligned. Then, the casing is tightened with bolts.

[0024] The first high-pressure fuel chamber 14 is provided with a first high-pressure fuel inlet 141 and a first high-pressure fuel outlet 142. First fuel enters through the first high-pressure fuel inlet 141 and the first fuel with adjusted pressure is output through the first high-pressure fuel outlet 142. The first low-pressure fuel chamber 15 is provided with a first low-pressure fuel outlet 151. When the fluid passage between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15 is connected, the first high-pressure fuel chamber 14 discharges the first fuel that has leaked through the fluid passage through the first low-pressure fuel outlet 151. Specifically, the first high-pressure fuel inlet 141 and the first high-pressure fuel outlet 142 are both connected to the first housing 11, and the first low-pressure fuel outlet 151 is connected to the second housing 12.

[0025] The second fuel high-pressure chamber 16 is provided with a second fuel high-pressure inlet 161 and a second fuel high-pressure outlet 162. The second fuel is introduced through the second fuel high-pressure inlet 161 and the second fuel with the adjusted pressure is output through the second fuel high-pressure outlet 162. Specifically, the second fuel high-pressure inlet 161 and the second fuel high-pressure outlet 162 are both connected to the second housing 12.

[0026] Preferably, the first fuel is methanol and the second fuel is diesel.

[0027] Specifically, the first high-pressure fuel inlet 141 and the first high-pressure fuel outlet 142 are connected to the first housing 11 by a high-pressure sealing gasket, and the second high-pressure fuel inlet 161 and the second high-pressure fuel outlet 162 are also connected to the second housing 12 by a high-pressure sealing gasket.

[0028] The valve sealing assembly 2 includes a valve seat 21, which is disposed between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15. The valve seat 21 has a connecting passage 22, with both ends connected to the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15, respectively. A ball valve 23 is mounted on the valve seat 21, abutting against the top of the plunger assembly 3. The ball valve 23 is axially movable. When the ball valve 23 moves to a first position, it blocks the connecting passage 22 of the valve seat 21, thereby cutting off the fluid passage between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15. When the ball valve 23 is separated from the first position, the connection passage 22 between the ball valve 23 and the valve seat 21 is separated, connecting the fluid passage between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15. The opening of the fluid passage is changed by changing the distance between the ball valve 23 and the valve seat 21 connection passage 22. Specifically, the valve seat 21 is fixedly connected inside the second housing 12. The connection between the valve seat 21 and the first high-pressure fuel chamber 14 is connected to the first housing 11 through a high-pressure sealing gasket. The connection between the valve seat 21 and the first low-pressure fuel chamber 15 is connected to the second housing 12 through a low-pressure sealing ring 7.

[0029] A push rod 24 is fixedly connected to the ball valve 23. The push rod 24 extends through the connecting passage 22 into the first fuel high-pressure chamber 14. One end of the push rod 24 extending into the first fuel high-pressure chamber 14 is fixedly connected to the spring 5. Specifically, the push rod 24 and the connecting passage 22 are fitted with a clearance.

[0030] The valve seat 21 has a sealing port that matches the shape of the ball valve 23. The sealing port of the valve seat 21 is the first position. When the ball valve 23 moves to the first position, that is, the ball valve 23 fits into the sealing port to block the connection passage 22 of the valve seat 21.

[0031] A limiting part 4 is provided below the valve seat 21, and a limiting groove 41 is provided in the limiting part 4. The ball valve 23 can slide along the limiting groove 41. Specifically, the limiting part 4 is fixedly connected to the second housing 12, and the limiting part 4 is located between the valve seat 21 and the plunger sleeve 31.

[0032] In the first embodiment of the connection method of spring 5, the end of spring 5 away from top rod 24 is fixedly connected to the first fuel high-pressure chamber 14.

[0033] In the second embodiment of the connection method of spring 5, a first opening is provided on the first fuel high-pressure chamber 14, and a first plug 17 is installed through the first opening. The end of spring 5 away from the top rod 24 is fixedly connected to the first plug 17.

[0034] Specifically, the first plug 17 is connected to the first housing 11 by a high-pressure sealing gasket.

[0035] Preferably, the first plug 17 is screwed to the first opening. By screwing the first plug 17, the pre-compression of the spring 5 can be changed, thereby enabling the constant differential pressure value to be conveniently set and calibrated from the outside. This greatly enhances the adaptability of the valve to different working conditions and the convenience of on-site debugging. Adjusting the pre-compression of the spring 5 is only performed during the installation, debugging, or maintenance of this constant differential pressure valve, which is a brief operation in a non-working state. The high-pressure sealing gasket between the first plug 17 and the first housing 11 has a certain elastic deformation capacity. When the plug is slowly rotated for adjustment (the adjustment range is small, within the elastic deformation range of the high-pressure sealing gasket), the high-pressure sealing gasket can undergo a slight elastic deformation with the axial displacement of the plug, and will not fail to seal.

[0036] The plunger assembly 3 includes a plunger sleeve 31, which is disposed inside the outer shell 1. A plunger body 32 is disposed inside the plunger sleeve 31. The plunger body 32 can slide relative to the plunger sleeve 31. The bottom end of the plunger body 32 is located inside the second fuel high-pressure chamber 16 to receive the real-time pressure of the second fuel high-pressure chamber 16. The top end of the plunger body 32 abuts against the ball valve 23. Specifically, the top end of the plunger body 32 passes through the limiting groove 41 of the limiting part 4 and abuts against the ball valve 23. The plunger sleeve 31 is fixedly connected to the second shell 12, and there is a transition fit between the plunger body 32 and the plunger sleeve 31.

[0037] The plunger sleeve 31 is connected to the second fuel high-pressure chamber 16 at the connection point via a high-pressure sealing gasket and to the second housing 12.

[0038] The second fuel high-pressure chamber 16 has a second opening, through which a second plug 18 is connected. The second plug 18 is connected to the second housing 12 by a high-pressure sealing gasket.

[0039] When the force exerted by the second high-pressure fuel chamber 16 on the bottom end of the plunger assembly 3 is equal to the sum of the force exerted by the first high-pressure fuel chamber 14 on the top end of the valve sealing assembly 2 and the preload force of the spring 5, the plunger assembly 3 and the valve sealing assembly 2 are in a state of force balance. The valve sealing assembly 2 is located at the critical position where the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15 are connected, so as to maintain a constant pressure difference between the first high-pressure fuel chamber 14 and the second high-pressure fuel chamber 16. Specifically, when the pressure exerted by the second high-pressure fuel chamber 16 on the bottom end of the plunger body 32 is equal to the sum of the pressure exerted by the first high-pressure fuel chamber 14 on the top end of the ball valve 23 and the preload force of the spring 5, the ball valve 23 of the valve sealing assembly 2 is located at the critical position where the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15 are connected. The force exerted by the second fuel high-pressure chamber 16 on the bottom end of the plunger assembly 3 is the pressure inside the second fuel high-pressure chamber 16 × the effective area of ​​the bottom end of the plunger body 32. The force exerted by the first fuel high-pressure chamber 14 on the top of the valve sealing assembly 2 is the pressure inside the first fuel high-pressure chamber 14 multiplied by the effective area of ​​the top of the ball valve 23.

[0040] The critical position is the dynamic equilibrium position in which the fluid passage between the first fuel high-pressure chamber 14 and the first fuel low-pressure chamber 15 is kept at a small opening when the valve sealing assembly 2 is under force equilibrium. At this time, the force of the second fuel high-pressure chamber 16 acting on the bottom end of the plunger assembly 3 is equal to the sum of the force of the first fuel high-pressure chamber 14 acting on the top end of the valve sealing assembly 2 and the spring preload.

[0041] At the critical position, a small gap is formed between the ball valve 23 and the valve seat 21, allowing the first fuel high-pressure chamber 14 to leak into the first fuel low-pressure chamber 15 through this gap. By adjusting the leakage flow rate, the pressure of the first fuel high-pressure chamber 14 can follow the pressure change of the second fuel high-pressure chamber 16 in real time, thereby maintaining a constant pressure difference between the two chambers.

[0042] Furthermore, the plunger assembly 3 is configured to drive the valve sealing assembly 2 to displace in response to pressure fluctuations in the second fuel high-pressure chamber 16, thereby adjusting the discharge flow of the first fuel high-pressure chamber 14 by changing the opening of the fluid passage, so that the pressure in the first fuel high-pressure chamber 14 follows the pressure changes in the second fuel high-pressure chamber 16 and maintains a constant pressure difference.

[0043] When the pressure rise in the second high-pressure fuel chamber 16 breaks the force balance, the plunger assembly 3 pushes the valve sealing assembly 2 to move closer to the first position, thereby reducing the opening of the fluid passage between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15. This reduces the discharge flow of the first high-pressure fuel chamber 14 and increases the pressure within it until the force balance is restored. Specifically, when the pressure rise in the second high-pressure fuel chamber 16 breaks the force balance, the plunger body 32 pushes the ball valve 23 to move closer to the first position. The distance between the ball valve 23 and the valve seat 21 connection passage 22 decreases, resulting in a decrease in the fluid passage opening. Consequently, the discharge flow of the first high-pressure fuel chamber 14 through the first low-pressure fuel outlet 151 decreases, causing the pressure within the first high-pressure fuel chamber 14 to rise until the force balance is restored.

[0044] When the pressure in the second high-pressure fuel chamber 16 decreases and breaks the force balance, the pressure in the first high-pressure fuel chamber 14 and the preload of the spring 5 push the valve sealing assembly 2 to move away from the first position, thereby increasing the opening of the fluid passage between the first high-pressure fuel chamber 14 and the first low-pressure fuel chamber 15. This increases the discharge flow of the first high-pressure fuel chamber 14 and reduces the pressure in the first high-pressure fuel chamber 14 until the force balance is restored. Specifically, when the pressure in the second high-pressure fuel chamber 16 decreases and breaks the force balance, the pressure in the first high-pressure fuel chamber 14 and the preload of the spring 5 push the ball valve 23 to move away from the first position. The distance between the ball valve 23 and the valve seat 21 connection passage 22 increases, resulting in an increase in the opening of the fluid passage. The discharge flow of the first high-pressure fuel chamber 14 through the first low-pressure fuel outlet 151 increases accordingly, causing the pressure in the first high-pressure fuel chamber 14 to decrease until the force balance is restored.

[0045] This constant pressure differential valve requires no external energy source, sensor, or controller. It achieves autonomous, reliable, and settable constant control of the pressure difference between two independent fluids solely through mechanical structure and fluid dynamics principles.

[0046] A method for maintaining a constant differential pressure valve, comprising the following steps: S1. The second fuel enters the second fuel high-pressure chamber 16, and the pressure acts on the bottom end of the plunger assembly 3, pushing the plunger assembly 3 and the valve sealing assembly 2 to move upward to the first position, so that the valve sealing assembly 2 is pressed to close the fluid passage between the first fuel high-pressure chamber 14 and the first fuel low-pressure chamber 15. Specifically, the second fuel enters the second fuel high-pressure chamber 16 through the second fuel high-pressure inlet 161. The pressure acts on the bottom end of the plunger body 32 of the plunger assembly 3. Under the pressure, the plunger body 32 moves upward and pushes the ball valve 23 in the valve sealing assembly 2 through its top end. The ball valve 23 slides along the limiting groove 41 of the limiting part 4 until it moves to the first position. The ball valve 23 completely blocks the connection passage 22 of the valve seat 21, realizing the physical isolation of the fluid passage between the first fuel high-pressure chamber 14 and the first fuel low-pressure chamber 15, ensuring no leakage. S2. The first fuel enters the first fuel high-pressure chamber 14, and the pressure acts on the top of the valve sealing assembly 2; Specifically, the first fuel enters the first fuel high-pressure chamber 14 through the first fuel high-pressure inlet 141, and the pressure acts directly on the top of the ball valve 23 of the valve sealing assembly 2.

[0047] S3. When the force exerted by the second high-pressure fuel chamber 16 on the bottom end of the plunger assembly 3 is less than the sum of the force exerted by the first high-pressure fuel chamber 14 on the top end of the valve sealing assembly 2 and the preload force of the spring 5, the valve sealing assembly 2 is pushed open and separated from the first position. The pressure in the first high-pressure fuel chamber 14 is released through the first low-pressure fuel chamber 15, resulting in a decrease in the pressure in the first high-pressure fuel chamber 14. Specifically, when the pressure exerted by the second high-pressure fuel chamber 16 on the bottom of the plunger body 32 is less than the sum of the pressure exerted by the first high-pressure fuel chamber 14 on the top of the ball valve 23 and the preload force of the spring 5, the force on the bottom of the plunger body 32 decreases, and it cannot resist the combined force of the preload force of the spring 5 and the pressure of the first high-pressure fuel chamber 14, thus pushing the ball valve 23 to move away from the first position and separating from the connection passage 22 of the valve seat 21. The pressure of the first high-pressure fuel chamber 14 flows into the first low-pressure fuel chamber 15 through the connection passage 22 and is finally discharged through the first low-pressure fuel outlet 151.

[0048] S4. As the pressure in the first fuel high-pressure chamber 14 decreases, when the pressure of the second fuel high-pressure chamber 16 acting on the bottom end of the plunger body 32 is equal to the sum of the pressure of the first fuel high-pressure chamber 14 acting on the top end of the ball valve 23 and the preload of the spring 5, the valve sealing assembly 2 is in a critical position of dynamic equilibrium, maintaining a constant pressure difference.

[0049] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A dual-fuel constant pressure differential valve, characterized in that, include: The outer casing has a first high-pressure fuel chamber, a first low-pressure fuel chamber and a second high-pressure fuel chamber inside it, and a first position is provided inside the outer casing. A valve sealing assembly is disposed within the housing. The valve sealing assembly is axially movable. When the valve sealing assembly moves to the first position, it cuts off the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber. When the valve sealing assembly is separated from the first position, it connects the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber, and the pressure in the first high-pressure fuel chamber is released through the first low-pressure fuel chamber. A plunger assembly is disposed within the housing. The bottom end of the plunger assembly is used to withstand the real-time pressure in the second fuel high-pressure chamber to move axially, and the top end of the plunger assembly abuts against the valve sealing assembly. A spring is located in the first high-pressure fuel chamber, and the spring applies a preload force to the valve sealing assembly; When the force exerted by the second high-pressure fuel chamber on the bottom of the plunger assembly is equal to the sum of the force exerted by the first high-pressure fuel chamber on the top of the valve sealing assembly and the preload of the spring, the plunger assembly and the valve sealing assembly are in a state of force equilibrium. The valve sealing assembly is located at the critical position where the first high-pressure fuel chamber and the first low-pressure fuel chamber are connected, so as to maintain a constant pressure difference between the first high-pressure fuel chamber and the second high-pressure fuel chamber. Furthermore, the plunger assembly is configured to drive the valve sealing assembly to displace in response to pressure fluctuations in the second fuel high-pressure chamber, thereby adjusting the discharge flow rate of the first fuel high-pressure chamber by changing the opening of the fluid passage, so that the pressure in the first fuel high-pressure chamber follows the pressure changes in the second fuel high-pressure chamber and maintains a constant pressure difference. The valve sealing assembly includes a valve seat disposed between a first high-pressure fuel chamber and a first low-pressure fuel chamber. The valve seat has a connecting passage and a ball valve is mounted on the valve seat. The ball valve abuts against the top of the plunger assembly and is axially movable. When the ball valve moves to the first position, it blocks the connecting passage of the valve seat to cut off the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber. When the ball valve is separated from the first position, the connecting passage between the ball valve and the valve seat is separated, connecting the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber. The opening degree of the fluid passage is changed by changing the distance between the ball valve and the connecting passage of the valve seat.

2. The dual-fuel constant pressure differential valve according to claim 1, characterized in that, When the pressure rise in the second high-pressure fuel chamber breaks the force balance, the plunger assembly pushes the valve sealing assembly to move closer to the first position to reduce the opening of the fluid passage between the first high-pressure fuel chamber and the first low-pressure fuel chamber, thereby reducing the leakage flow of the first high-pressure fuel chamber and increasing the pressure in the first high-pressure fuel chamber until the force balance is restored.

3. The dual-fuel constant pressure differential valve according to claim 2, characterized in that, When the pressure in the second high-pressure fuel chamber decreases and breaks the force balance, the force exerted by the first high-pressure fuel chamber on the top of the valve sealing assembly and the preload of the spring push the valve sealing assembly to move away from the first position, thereby increasing the fluid passage opening between the first high-pressure fuel chamber and the first low-pressure fuel chamber, increasing the discharge flow of the first high-pressure fuel chamber and decreasing the pressure in the first high-pressure fuel chamber until the force balance is restored.

4. The dual-fuel constant pressure differential valve according to claim 1, characterized in that, The first fuel high-pressure chamber is provided with a first fuel high-pressure inlet and a first fuel high-pressure outlet. First fuel is introduced through the first fuel high-pressure inlet and the first fuel with adjusted pressure is output through the first fuel high-pressure outlet. The first fuel low-pressure chamber is provided with a first fuel low-pressure outlet. When the fluid passage between the first fuel high-pressure chamber and the first fuel low-pressure chamber is connected, the first fuel high-pressure chamber discharges the first fuel that has been drained through the fluid passage through the first fuel low-pressure outlet.

5. The dual-fuel constant pressure differential valve according to claim 4, characterized in that, The second fuel high-pressure chamber is equipped with a second fuel high-pressure inlet and a second fuel high-pressure outlet. Second fuel is introduced through the second fuel high-pressure inlet and the second fuel with adjusted pressure is output through the second fuel high-pressure outlet.

6. The dual-fuel constant pressure differential valve according to claim 1, characterized in that, A push rod is fixedly connected to the ball valve. The push rod extends through the connecting passage into the first fuel high-pressure chamber, and one end of the push rod extending into the first fuel high-pressure chamber is fixedly connected to a spring.

7. The dual-fuel constant pressure differential valve according to claim 6, characterized in that, A limiting part is provided below the valve seat, and a limiting groove is opened in the limiting part, so that the ball valve can slide along the limiting groove.

8. The dual-fuel constant pressure differential valve according to claim 6, characterized in that, The plunger assembly includes a plunger sleeve housed within a housing, a plunger body housed within the plunger sleeve, the plunger body being slidable relative to the plunger sleeve, the bottom end of the plunger body being located within a second fuel high-pressure chamber to receive the real-time pressure of the second fuel high-pressure chamber, and the top end of the plunger body abutting against a ball valve.

9. A method for maintaining constant differential pressure in a constant differential pressure valve, characterized in that, Adjusting the constant pressure differential valve as described in any one of claims 1-8 includes the following steps: S1. The second fuel enters the second fuel high-pressure chamber, and the pressure acts on the bottom end of the plunger assembly, pushing the plunger assembly and valve sealing assembly to move upward to the first position, so that the valve sealing assembly is pressed to close the fluid passage between the first fuel high-pressure chamber and the first fuel low-pressure chamber. S2. The first fuel enters the first fuel high-pressure chamber, and the pressure acts on the top of the valve sealing assembly; S3. When the force exerted by the second high-pressure fuel chamber on the bottom end of the plunger assembly is less than the sum of the force exerted by the first high-pressure fuel chamber on the top end of the valve sealing assembly and the preload force of the spring, the valve sealing assembly is pushed open and separated from the first position. The pressure in the first high-pressure fuel chamber is released through the first low-pressure fuel chamber, resulting in a decrease in the pressure in the first high-pressure fuel chamber. S4. As the pressure in the first high-pressure fuel chamber decreases, when the force exerted by the second high-pressure fuel chamber on the bottom of the plunger assembly equals the sum of the force exerted by the first high-pressure fuel chamber on the top of the valve sealing assembly and the preload of the spring, the valve sealing assembly is in a critical position of dynamic equilibrium, maintaining a constant pressure difference.

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