Oil source output pressure stabilizing and adjusting device and process method thereof

Abstract

The present application relates to the technical field of aircraft hydraulic stabilizing adjustment process, and particularly relates to an oil source output pressure stabilizing adjustment device and a process method thereof, which comprises: a variable plunger pump; a pressure compensator; and a proportional pressure relief valve, and the specific steps are as follows: S1, oil pump motor starts; S2, when the pressure P is lower than the pre-tightening pressure regulated by the proportional pressure relief valve; S3, when the pressure P reaches the pre-tightening pressure regulated by the proportional pressure relief valve; the compensating system of the present application has an active pressure relief function, still has a stable compensating adjustment function under low working pressure, and can realize continuous stable adjustment of 2.6-28 MPa pressure. This control mode has the advantages of convenient pressure adjustment, reliable work, and can realize stable, automatic, fast and direct adjustment of the output pressure of the pump source, and can realize computer automatic control, and can effectively guarantee the accurate detection of the DDV aircraft according to the working condition.

Description

Technical Field

[0001] This invention relates to the field of aircraft hydraulic stabilization and regulation technology, specifically to an oil source output pressure stabilization and regulation device and its process method. Background Technology

[0002] Direct-drive servo valves (DDVs) are crucial components in aircraft. Their key feature is the direct drive of the main valve core by a force motor. This direct connection method, compared to EHVs (electro-Hydraulic servo valves) which rely on jet-generated pressure differentials to drive the valve core, significantly reduces static leakage, improves resistance to oil contamination, simplifies the product structure, and enhances reliability and maintainability. DDV force motors utilize rare-earth permanent magnet materials and low-inertia iron cores, providing substantial output force and ensuring high response and high-frequency band requirements. DDVs offer significant advantages over EHV electro-hydraulic servo valves due to their simplicity, light weight, small size, low cost, low internal leakage, low onboard power consumption, high reliability, and ease of BIT testing.

[0003] Because the DDV directly distributes oil to the working chamber of the actuator cylinder, driving the piston rod to bear tens of tons of control surface load, the working flow is large during maneuvering flight, and its oil source output pressure can be kept stable. Achieving stable pressure regulation is a key technology to ensure that the DDV aircraft can accurately control and complete flight control tasks. The original control method that only relies on constant pressure variable pumps is far from meeting the requirements of DDV operating environment testing. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes an oil source output pressure stabilization and regulation device and its process method.

[0005] An oil source output pressure stabilization and regulation device, comprising:

[0006] The variable displacement piston pump is fixedly installed on the piston pump housing to ensure the normal connection between the pressure compensator and the swashplate, and to ensure the sealing between the pressure compensator and the pump housing and the oil circuit connection.

[0007] The pressure compensator is installed inside the variable displacement piston pump and is used to finely adjust the tilt angle of the piston pump swashplate.

[0008] The proportional pressure relief valve is fixedly installed on the piston pump housing and changes proportionally or programmatically to achieve remote computer control.

[0009] The variable displacement piston pump is composed of a conventional variable displacement piston pump with a spring-loaded pressure servo mechanism driving the swashplate tilt angle.

[0010] As a further improvement of the present invention, the pressure compensator includes a connecting block fixedly connected to the plunger pump swashplate by a connecting pin, a piston rod that can slide up and down without clearance by another connecting pin fixedly connected to the connecting block, a cylinder for cooperating with the piston rod to form an actuating cylinder, and an adjusting screw for adjusting the maximum stroke of the piston rod.

[0011] As a further improvement of the present invention, the plunger pump swashplate is fixedly riveted to the left end of the connecting block; the right end of the connecting block is interference-fitted with the piston rod.

[0012] As a further improvement of the present invention, the two fork ears on the left end of the piston rod have square holes with upper and lower arc transitions. The radius of the holes is the same as the radius of the connecting pin, and the width of the holes is the same as the diameter of the connecting pin, allowing for seamless sliding fit with the connecting pin.

[0013] As a further improvement of the present invention, the left and right cavities of the cylinder are subjected to proportional pressure compensation, and the piston rod and connecting block are driven by taking into account the area difference between the left and right cavities.

[0014] As a further improvement of the present invention, the proportional pressure relief valve includes a proportional pressure valve formed by adding a spring with a stable elastic coefficient and a pressure adjusting nut to a normal two-position three-way valve, a relief valve that generates an electromagnetic thrust proportional to the current after inputting an electromagnet, a first throttling valve that adjusts the throttling ratio according to the magnitude of the starting pressure of the proportional pressure valve core, and a second throttling valve that adjusts the throttling ratio according to the elastic coefficient of the spring of the oil pump pressure servo mechanism.

[0015] As a further improvement of the present invention, the relief valve is a pilot-operated proportional relief valve.

[0016] As another improvement of the present invention, a process method for a stable oil source output pressure regulating device is proposed, the specific steps of which are as follows:

[0017] S1. Oil pump motor start: The potentiometer or computer gives a command signal, and the variable piston pump outputs a certain pressure flow for DDV use;

[0018] S2. When the pressure P is lower than the preload pressure set by the proportional pressure relief valve:

[0019] a. When the proportional pressure relief valve is closed and there is no flow output, there is no oil flow through its relief valve and the first throttle valve, and the pressure before and after the first throttle valve is equal.

[0020] b. The proportional pressure valve is closed, no oil flows through the second throttle valve, the pressures before and after the second throttle valve are equal and both are 0, and the pressure at port A is 0.

[0021] c. Under the action of the output pressure P of the variable piston pump, the piston rod of the pressure compensator is at the right limit position, so that the swashplate is working at the maximum tilt angle, the flow rate is the maximum, and it continues until the pressure P reaches a level that can meet the requirements of DDV.

[0022] S3. When the pressure P reaches the preload pressure set by the proportional pressure relief valve:

[0023] a. When the overflow valve is in the open state and there is overflow output, the first throttle valve plays a throttling role, and a pressure difference is generated before and after the first throttle valve;

[0024] b. When the pressure difference is greater than the preload of the proportional pressure valve, the proportional pressure valve enters the working state in the left position, connecting port P and port A. Oil flows through the second throttle valve, and the second throttle valve plays a throttling role. A pressure difference is generated before and after the second throttle valve, and the pressure difference acts on the right end of the piston rod of the pressure compensator.

[0025] c. When the pressure P at the left end of the piston rod is greater than the pressure at port A, due to the design difference in the hydraulic action area between the left and right sides of the piston rod, even if the pressure at port A at the right end of the piston rod is less than the pressure P at the left end, the piston rod can still be driven to move to the left, which reduces the swashplate tilt angle and the output flow of the variable piston pump.

[0026] When the pressure P reaches the pre-tightening pressure set by the proportional pressure relief valve, it matches the operating pressure of the DDV.

[0027] The beneficial effects of this invention are as follows: The compensation system of this invention has an active pressure relief function and still has a stable compensation and regulation function under low operating pressure, enabling continuous and stable pressure regulation from 2.6 to 28 MPa. This control method is convenient for pressure adjustment, reliable in operation, and can achieve stable, automatic, rapid, and direct adjustment of the pump source output pressure. Moreover, it can achieve automatic computer control, effectively ensuring accurate detection of DDV aircraft according to operating conditions, improving the testing efficiency and maintenance verification quality of direct-drive servo valves, and has broad application prospects with significant military, economic, and social benefits. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0029] Figure 1 This is a schematic diagram of the principle structure of the present invention;

[0030] Figure 2 This is a schematic diagram of the variable displacement piston pump and pressure compensator of the present invention. Figure 1 ;

[0031] Figure 3 This is a schematic diagram of the variable displacement piston pump and pressure compensator of the present invention. Figure 2 ;

[0032] Figure 4 This is a schematic diagram of the main structure of the pressure compensator of the present invention;

[0033] Figure 5 This is a schematic diagram of the proportional pressure relief valve of the present invention.

[0034] Figure 6 This is a schematic diagram illustrating the structural principle of the present invention.

[0035] In the diagram, 1 is a variable displacement piston pump; 2 is a pressure compensator; 201 is a connecting pin; 202 is a connecting block; 203 is a piston rod; 204 is a cylinder; 205 is an adjusting screw; 3 is a proportional pressure relief valve; 301 is a proportional pressure valve; 302 is a relief valve; 303 is a first throttle valve; and 304 is a second throttle valve. Detailed Implementation

[0036] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below.

[0037] like Figures 1 to 6 As shown, an oil source output pressure stabilization and regulation device includes:

[0038] Variable displacement piston pump 1 is fixedly installed on the piston pump housing to ensure normal connection between the pressure compensator and the swashplate, and to ensure the sealing between the pressure compensator and the pump housing and the oil circuit connection.

[0039] Pressure compensator 2 is installed in the inner cavity of variable piston pump 1 and is used to finely adjust the tilt angle of the piston pump swashplate.

[0040] The proportional pressure relief valve 3 is fixedly installed on the piston pump housing and changes proportionally or programmatically to achieve remote computer control.

[0041] The variable displacement piston pump 1 is composed of a conventional variable displacement piston pump with a pressure servo mechanism with a spring driving the tilt angle of the swashplate.

[0042] This invention provides a novel control method for the oil source pump used in the testing and inspection of direct-drive servo valves in aircraft. Specifically, it employs a remote proportional pressure regulation control method using a pressure compensator on top of a constant pressure variable. This method achieves continuous and stable pressure regulation from 2.6 to 28 MPa, meeting the pressure stability requirements of direct-drive servo valves. This ensures accurate testing of DDV aircraft based on operating conditions, improving the efficiency of direct-drive servo valve testing and inspection, and enhancing the quality of maintenance verification.

[0043] The pressure compensator 2 includes a connecting block 202 fixedly connected to the plunger pump swashplate via a connecting pin 201, a piston rod 203 that can slide up and down without clearance via another connecting pin 201 fixedly connected to the connecting block 202, a cylinder 204 that cooperates with the piston rod 203 to form an actuating cylinder, and an adjusting screw 205 for adjusting the maximum stroke of the piston rod 203.

[0044] Based on the pressure stability requirements of the DDV direct drive servo valve test, the variable piston pump 1 is subjected to secondary processing according to the relevant dimensions of the pressure compensator 2 and the proportional pressure relief valve 3 to ensure that the pressure compensator 2 is properly connected to the pump swashplate and that the pressure compensator is sealed to the pump housing and connected to the oil circuit.

[0045] The compensation system of this invention has an active pressure relief function and maintains stable compensation and regulation capabilities even at low operating pressures, enabling continuous and stable pressure regulation from 2.6 to 28 MPa. This control method offers convenient pressure adjustment, reliable operation, and the ability to achieve stable, automatic, rapid, and direct adjustment of the pump source's output pressure. Furthermore, it allows for automatic computer control, effectively ensuring accurate testing of DDV aircraft based on operating conditions, improving the efficiency of direct-drive servo valve testing and inspection, and enhancing maintenance verification quality. With broad application prospects, it offers significant military, economic, and social benefits.

[0046] The pressure compensator and proportional pressure relief valve are fixedly installed on the plunger pump housing using bolts.

[0047] The plunger pump swashplate is fixedly riveted to the left end of the connecting block 202; the right end of the connecting block 202 is interference-fitted to the piston rod 203.

[0048] Based on the constant pressure variable pressure system, an additional pressure compensator is installed with a proportional pressure relief valve to regulate the output pressure. Fine pressure adjustment can be achieved by adjusting the potentiometer on the operating platform, or remote proportional pressure control can be implemented via computer. The system is continuously adjustable from 2.6 to 28 MPa.

[0049] The control process involves sending a command signal from a potentiometer or computer to a proportional controller. The controller then controls the proportional relief valve to output pressure. The pressure is detected by a pressure sensor (Mp1) and input to the computer control system via a pressure transmitter and data acquisition card for closed-loop control to stably regulate the pump's output pressure. The pump's output pressure is proportional to the electrical signal command input.

[0050] The pressure compensator 2 is configured and rigidly connected to the connecting block 202 via the connecting pin 201. The connecting pin 201 and the two forks at the left end of the piston rod 203 slide without clearance, ensuring that the linear displacement of the piston rod 203 adapts to the arc motion of the output point and avoiding force interference caused by the height difference between the horizontal linear motion and the arc motion.

[0051] The piston rod 203 has two square holes at the left end with rounded upper and lower edges. The radius of the holes is the same as the radius of the connecting pin 201, and the width of the holes is the same as the diameter of the connecting pin 201. The holes slide up and down without gaps with the connecting pin 201.

[0052] The left and right cavities of the cylinder 204 receive proportional pressure compensation, and the difference in area between the left and right cavities is taken into account to drive the piston rod 203 and the connecting block 202.

[0053] The design of the left and right chamber area difference of the cylinder 204 and piston rod 203 ensures that the hydraulic action area of ​​the rod chamber and the rodless chamber matches the pressure compensation requirements, thereby finely adjusting the tilt angle of the plunger pump swashplate and adjusting the maximum stroke of the piston rod by adjusting the screw to ensure the matching adjustment of the maximum tilt angle of the swashplate.

[0054] To meet the pressure stability requirements of the drive servo valve, secondary processing and modification were carried out on a common variable piston pump with a spring-loaded pressure servo mechanism that drives the swashplate tilt angle, which has almost the same form and specifications.

[0055] The proportional pressure relief valve 3 includes a proportional pressure valve 301 formed by adding a spring with a stable elastic coefficient and a pressure adjusting nut to a normal two-position three-way valve, a relief valve 302 that generates an electromagnetic thrust proportional to the current after inputting an electromagnet, a first throttling valve 303 that adjusts the throttling ratio according to the magnitude of the valve core starting pressure of the proportional pressure valve 301, and a second throttling valve 304 that adjusts the throttling ratio according to the elastic coefficient of the spring of the oil pump pressure servo mechanism.

[0056] The relief valve 302 is a pilot-operated proportional relief valve. The electromagnetic thrust generated acts on the pilot valve core through a push rod and spring. The pressure required to open the pilot valve core is the pressure set by the system. Therefore, the system pressure is proportional to the input current. If the input current changes proportionally or according to a certain program, the system pressure controlled by the proportional relief valve also changes proportionally or according to a certain program, which facilitates remote computer control.

[0057] The proportional pressure relief valve 3 selects the stable elastic coefficient spring and the throttling coefficient of the first throttling valve 303 through the proportional pressure valve 301. The system pressure and input current are proportional through the relief valve 302, which can be easily remotely controlled by a computer, and realizes continuous and stable adjustment of 2.6 to 28 MPa pressure by DDV direct drive servo valve.

[0058] A process method for a device for stabilizing and regulating oil source output pressure includes the following specific steps:

[0059] S1. Oil pump motor start: The potentiometer or computer gives a command signal, and the variable piston pump 1 outputs a certain pressure flow for DDV to use;

[0060] S2. When the pressure P is lower than the preload pressure set by the proportional pressure relief valve 3:

[0061] a. The proportional pressure relief valve 3 is in the closed state with no flow output. No oil flows through its relief valve 302 and the first throttle valve 303. The pressure before and after the first throttle valve 303 is equal.

[0062] b. The proportional pressure valve 301 is closed, no oil flows through the second throttle valve 304, the pressures before and after the second throttle valve 304 are equal and both are 0, and the pressure at port A is 0.

[0063] c. Under the action of the output pressure P of the variable piston pump 1, the piston rod 203 of the pressure compensator 2 is in the right limit position, so that the swashplate is in the maximum tilt angle and the flow rate is the maximum, and it continues until the pressure P reaches a level that can meet the requirements of DDV.

[0064] S3. When the pressure P reaches the preload pressure set by the proportional pressure relief valve 3:

[0065] a. When the overflow valve 302 is in the open state and has overflow output, the first throttle valve 303 plays a throttling role, and a pressure difference is generated before and after the first throttle valve 303;

[0066] b. When the pressure difference is greater than the preload of the proportional pressure valve 301, the proportional pressure valve 301 enters the working state in the left position, so that the P port is connected to the A port, and oil flows through the second throttle valve 304. At this time, the second throttle valve 304 plays a throttling role, and a pressure difference is generated before and after the second throttle valve 304. The pressure difference acts on the right end of the piston rod 203 of the pressure compensator 2.

[0067] c. When the pressure P at the left end of piston rod 203 is greater than the pressure at port A, due to the design difference in hydraulic action area between the left and right ends of piston rod 203, even when the pressure at port A at the right end of piston rod 203 is less than the pressure P at the left end, piston rod 203 can still be driven to move to the left, thus reducing the swashplate tilt angle and the output flow of variable piston pump 1.

[0068] At the same time, the preload of the spring of the pressure servo mechanism of the variable piston pump 1 is increased, which suppresses the further reduction of the swashplate tilt angle and finally stabilizes it at a certain angle.

[0069] When the pressure reaches a certain value, the swashplate angle approaches 0, there is no flow output, and the pressure stabilizes at a certain design-set pressure value.

[0070] In this process, the flow rate decreases continuously as the pressure increases, and the relationship between the flow rate and pressure is determined by the characteristics of the pressure compensator 2 and the proportional pressure relief valve 3.

[0071] This control method can significantly improve control performance, changing the pressure adjustment from the original jerky type to the smooth type controlled by the proportional valve, avoiding hydraulic shock and vibration caused by pressure adjustment, so that the pump's output pressure can be adjusted smoothly.

[0072] When the pressure P reaches the pre-tightening pressure set by the proportional pressure relief valve 3, it matches the operating pressure of the DDV.

[0073] The oil source output pressure stabilization adjustment process is convenient, reliable, and can achieve stable, automatic, fast and direct adjustment of the pump source output pressure. Moreover, it can achieve automatic computer control, which can effectively ensure accurate testing of DDV aircraft according to operating conditions, and improve the testing efficiency and maintenance verification quality of direct drive servo valves.

[0074] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely prisms of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A device for stabilizing and regulating oil source output pressure, characterized in that: include: The variable piston pump (1) is fixedly installed on the piston pump housing to ensure the normal connection between the pressure compensator and the swashplate, and to ensure the sealing between the pressure compensator and the pump housing and the oil circuit connection. Pressure compensator (2) is installed in the inner cavity of variable piston pump (1) for fine adjustment of the tilt angle of piston pump swashplate; The proportional pressure relief valve (3) is fixedly installed on the piston pump housing and changes proportionally or programmatically to achieve remote computer control. The pressure compensator (2) includes a connecting block (202) fixedly connected to the plunger pump swashplate via a connecting pin (201), a piston rod (203) which can slide up and down without clearance via another connecting pin (201) fixedly connected to the connecting block (202), a cylinder (204) for cooperating with the piston rod (203) to form an actuating cylinder, and an adjusting screw (205) for adjusting the maximum stroke of the piston rod (203); the proportional pressure relief valve (3) includes a proportional pressure valve (301) formed by adding a spring with a stable elastic coefficient and a pressure adjusting nut to a regular two-position three-way valve, a relief valve (302) that generates an electromagnetic thrust proportional to the current after inputting an electromagnet, a first throttle valve (303) that adjusts the throttle ratio according to the magnitude of the valve core starting pressure of the proportional pressure valve (301), and a second throttle valve (304) that adjusts the throttle ratio according to the elastic coefficient of the spring of the oil pump pressure servo mechanism.

2. The oil source output pressure stabilizing and regulating device according to claim 1, characterized in that: The variable piston pump (1) is composed of a common variable piston pump with a pressure servo mechanism with a spring driving the tilt angle of the swashplate.

3. The oil source output pressure stabilizing and regulating device according to claim 2, characterized in that: The plunger pump swashplate is fixedly riveted to the left end of the connecting block (202); the right end of the connecting block (202) is interference-fitted to the piston rod (203).

4. The oil source output pressure stabilizing and regulating device according to claim 1, characterized in that: The piston rod (203) has two square holes at the left end with rounded upper and lower arcs. The radius of the holes is the same as the radius of the connecting pin (201), and the width of the holes is the same as the diameter of the connecting pin (201). The holes slide up and down without gaps with the connecting pin (201).

5. The oil source output pressure stabilization and regulation device according to claim 1, characterized in that: The cylinder (204) receives proportional pressure compensation in its left and right cavities, while taking into account the area difference between the left and right cavities to drive the piston rod (203) and the connecting block (202).

6. The oil source output pressure stabilizing and regulating device according to claim 1, characterized in that: The relief valve (302) is a pilot-operated proportional relief valve.

7. A process method using the oil source output pressure stabilization and regulation device according to any one of claims 1 to 6, characterized in that: The specific steps are as follows: S1. Oil pump motor starts: The potentiometer or computer gives a command signal, and the variable piston pump (1) outputs a certain pressure flow for DDV to use; S2. When the pressure P is lower than the preload pressure set by the proportional pressure relief valve (3): a. The proportional pressure relief valve (3) is in the closed state and there is no flow output. There is no oil flow through its relief valve (302) and the first throttle valve (303). The pressure before and after the first throttle valve (303) is equal. b. The proportional pressure valve (301) is closed, no oil flows through the second throttle valve (304), the pressures before and after the second throttle valve (304) are equal and both are 0, and the pressure at port A is 0; c. Under the action of the output pressure P of the variable piston pump (1), the piston rod (203) of the pressure compensator (2) is in the right limit position, so that the swashplate is in the maximum tilt angle, the flow rate is the maximum, and it continues until the pressure P reaches a level that can meet the requirements of DDV. S3. When the pressure P reaches the preload pressure set by the proportional pressure relief valve 3: a. When the overflow valve (302) is in the open state and has overflow output, the first throttle valve (303) plays a throttling role, and a pressure difference is generated before and after the first throttle valve (303); b. When the pressure difference is greater than the preload of the proportional pressure valve (301), the proportional pressure valve (301) enters the working state in the left position, so that the P port is connected to the A port, and oil flows through the second throttle valve (304). At this time, the second throttle valve (304) plays a throttling role, and a pressure difference is generated before and after the second throttle valve (304). The pressure difference acts on the right end of the piston rod (203) of the pressure compensator (2). c. When the pressure P at the left end of the piston rod (203) is greater than the pressure at port A, due to the design of the difference in hydraulic action area between the left and right sides of the piston rod (203), even if the pressure at port A at the right end of the piston rod (203) is less than the pressure P at the left end, the piston rod (203) can still be driven to move to the left, which makes the swashplate tilt angle smaller and the output flow of the variable piston pump (1) smaller.

8. The process method of the oil source output pressure stabilization and regulation device according to claim 7, characterized in that: When the pressure P reaches the pre-tightening pressure set by the proportional pressure relief valve (3), it matches the operating pressure of the DDV.

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