Pressure smooth opening electromagnetic device for multi-oil circuit multi-electric aircraft engine fuel system

Abstract

The present invention discloses a pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system, which is used to achieve smooth switching and precise pressure control between multiple oil circuits in the fuel system, and effectively reduce the electromagnetic force requirement; the device includes a valve body base, a main valve assembly, an auxiliary valve assembly and an electromagnetically actuated pilot valve assembly. The main valve adopts a conical structure to ensure a good seal with the valve port and achieve smooth passage of fluid through a small flow channel hole. At the same time, combined with relevant theories of fluid mechanics, the main valve structure is optimized and designed, and the electromagnetic force requirement is effectively reduced when the main valve is actuated. In addition, the auxiliary valve is designed as a one-way valve to ensure the unidirectionality of fuel flow and the stability of system pressure when multiple oil circuits are switched, thereby improving the reliability of the system. The device achieves smooth switching and precise pressure control between multiple oil circuits through the coordinated work of various components, significantly improving the stability and reliability of the aircraft engine multi-oil-circuit fuel system.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft engine fuel system control, and relates to pressure regulation and solenoid valve design for multi-oil-circuit fuel systems. Specifically, it is a pressure-smooth opening electromagnetic device suitable for multi-oil-circuit, multi-electric aircraft engine fuel systems. The device is used to achieve smooth transition and precise control of the fuel system when switching between different oil circuits, and reduce the required electromagnetic force. Background Art

[0002] With the continuous development of aircraft engine technology, more-electric aircraft engines have gradually become a key research direction in the aviation field. Traditional aircraft engines typically rely on fuel pumps and hydraulic actuators driven by the accessory case for fuel supply and actuation control. However, more-electric aircraft engines use electric fuel pumps and electric actuators to replace the traditional accessory case-driven fuel pumps and hydraulic actuators. This technological shift not only increases the level of electrification of the system, but also improves the control precision and response speed of the fuel system, helping to optimize overall engine performance.

[0003] In multi-oil and multi-electric aircraft engines, such as Figure 1 As shown, a fuel system typically consists of multiple parallel oil circuits. To ensure stable engine operation under various operating conditions, smooth and continuous fuel supply from the priority oil circuit (line 1) and the main oil circuit (line 2) is extremely important. This process plays a key role in aircraft engine ignition, acceleration, and stable operation. Since the traditional fuel regulator has been eliminated, the fuel system requires solenoid valves in the two oil circuits to control the opening and closing of the oil circuits. The introduction of solenoid valves enables automated control and improved response speed of the fuel system. However, traditional solenoid valves have only two states when powered on or off: fully closed when powered on and fully open when powered off. Because the fuel system of a multi-electric, multi-oil engine has lines 1 and 2 connected in parallel, the oil pressure in line 1 drops sharply the moment line 2 opens, resulting in a momentary shortage of oil flow in line 1. This sudden change in oil pressure and flow can easily cause engine ignition failure, significantly affecting the engine's starting performance and stable operation.

[0004] Furthermore, the fuel supply characteristics of the engine's main oil circuit (line 2) also posed challenges to the solenoid valve design. Due to the high flow rate and system pressure in the engine's main oil circuit (line 2), the solenoid valve spool is subject to significant hydraulic pressure, resulting in a high electromagnetic force required to actuate the valve spool (opening / closing). This, in turn, results in a larger solenoid valve structure, which consumes more space and weight within the aircraft engine.

[0005] Traditional solenoid valves have certain limitations in their combination of hydraulic drive and electromagnetic control. First, because the solenoid valve must possess sufficient electromagnetic force to overcome high hydraulic pressure, the size and power requirements of its electromagnetic components increase. This not only places higher demands on the system power supply, but also increases the maintenance cost and complexity of aircraft engines. Second, the increased size of the solenoid valve makes it difficult to install flexibly, especially within the space-constrained internal structure of aircraft engines, which can easily lead to installation difficulties and waste of space. Furthermore, when the engine requires frequent oil circuit switching, the response speed and control accuracy of traditional solenoid valves may be insufficient, resulting in limited timeliness and stability of fuel supply.

[0006] In summary, as aircraft engines continue to evolve toward higher efficiency, lighter weight, and higher reliability, the design of fuel supply systems for multi-electric, multi-fuel circuit aircraft engines requires further optimization. To address the challenges of traditional solenoid valves in multi-fuel circuit systems, such as fluctuating fuel supply pressures, high valve core forces, and bulky electromagnetic structures, developing an electromagnetic device that can achieve smooth pressure opening in multi-fuel circuit aircraft engine fuel systems while also possessing a compact structure and requiring minimal electromagnetic force is a pressing technical challenge in the field of multi-electric aircraft engines. Summary of the Invention

[0007] (1) Purpose of the invention

[0008] In view of the defects and shortcomings of the existing multi-oil-circuit and multi-electric aviation engine fuel system, such as unstable oil supply pressure, large valve core liquid pressure, large electromagnetic force demand, and large electromagnetic structure volume, in order to solve at least one of the above-mentioned and other technical problems in the prior art, the present invention aims to provide a pressure-smooth opening electromagnetic device suitable for multi-oil-circuit and multi-electric aviation engine fuel system. In combination with relevant fluid mechanics theories, through the optimization design of the solenoid valve structure, the pilot valve, main valve and auxiliary valve are controlled in stages to reasonably distribute the fluid pressure, and the Bernoulli equation is used to accurately calculate the fluid pressure during the valve opening and closing process, so as to reduce the electromagnetic force while meeting the smooth opening of the multi-oil-circuit system pressure, thereby reducing the demand for electromagnetic force, reducing the volume and weight of the electromagnetic structure, and improving the installation adaptability of the device and the operating stability of the aviation engine system.

[0009] (2) Technical solution

[0010] In order to achieve the purpose of the invention and solve the technical problems, the present invention adopts the following technical solutions:

[0011] A pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system is used to achieve smooth switching and pressure control between different oil circuits in the fuel system of a multi-oil-circuit, multi-electric aircraft engine, avoiding oil pressure fluctuations and unstable fuel supply during the switching process, reducing the required electromagnetic force, and ensuring stable operation of the aircraft engine. The device comprises at least a valve body base, a main valve assembly, a secondary valve assembly, and an electromagnetically actuated pilot valve assembly. Specifically:

[0012] The valve body base is provided with an oil flow channel, a main valve mounting valve port and an auxiliary valve mounting valve port, wherein: the oil flow channel is provided with a partition plate that divides it into an upstream oil inlet section and a downstream oil outlet section; the main valve mounting valve port is arranged at the top of the valve body base, and is a cylindrical structure extending in the height direction as a whole, and its bottom is provided with at least one main oil outlet hole communicating with the upstream oil inlet section and one main oil return hole communicating with the downstream oil outlet section; the auxiliary valve mounting valve port is a blind hole channel structure extending in the horizontal direction with one end closed and the other end open, and its side wall is provided with at least one auxiliary oil outlet hole communicating with the upstream oil inlet section and one auxiliary oil return hole communicating with the downstream oil outlet section;

[0013] The main valve assembly comprises at least a main valve and a main valve return spring, the main valve being arranged in the main valve mounting valve port, and being a plate-like structural member with an annular skirt as a whole, the annular skirt forming a clearance fit with the circumferential side wall of the main valve mounting valve port, and its top surface being higher than the top surface of the plate-like structural member; the center of the bottom surface of the plate-like structural member protrudes downward to form a conical structure facing the main oil return hole, the center of the top surface is provided with a downwardly concave sealing gasket accommodating groove, the bottom of the groove is provided with a central oil return hole penetrating downwardly through the conical structure, and the plate-like structural member is further provided with a plurality of oil holes penetrating its top and bottom surfaces and distributed circumferentially; the main valve return spring is installed between the plate-like structural member of the main valve and the bottom wall of the main valve mounting valve port;

[0014] The auxiliary valve assembly is formed as a one-way valve as a whole, comprising at least a valve seat, a steel ball, a ball holder, a secondary valve return spring and a one-way valve seat arranged axially along the blind hole channel of the auxiliary valve mounting valve port, wherein: the valve seat is arranged at an axial position corresponding to the partition plate, and is provided with a central through hole extending axially along the channel, and the channel space in front of the valve seat is communicated with the auxiliary oil outlet hole; the steel ball, the ball holder and the auxiliary valve return spring are sequentially arranged in the inner cavity of the one-way valve seat; the top of the one-way valve seat is against the rear end surface of the valve seat, and a radial gap is formed between the front end side wall and the inner wall of the channel and is communicated with the auxiliary oil return hole, and a plurality of oil holes are provided on the front end side wall, and the rear end side wall is sealed and fixedly arranged on the auxiliary valve mounting valve port;

[0015] The electromagnetically actuated pilot valve assembly is installed on the top of the valve body base, and includes at least a moving iron core driven by an electromagnetic coil and a spring-reset pilot valve, wherein: the pilot valve includes at least a valve rod and a sealing gasket, the upper end of the valve rod is fixedly connected to the end of the moving iron core, and the sealing gasket is fixedly arranged at the lower end of the valve rod, and is used to cooperate with the sealing gasket receiving groove at the top of the main valve to form a seal; the moving iron core drives the valve rod to move axially through the power-on operation of the electromagnetic coil, and when the electromagnetic coil is de-energized, the reset spring pushes the moving iron core and the valve rod back to the initial position.

[0016] (3) Technical effects

[0017] Compared with the prior art, the pressure-smooth opening electromagnetic device for a multi-oil-circuit aircraft engine fuel system of the present invention has the following beneficial and significant technical effects:

[0018] (1) The present invention achieves smooth switching and pressure control between different oil circuits in a multi-oil-circuit aircraft engine fuel system by designing a coordinated working mechanism among the main valve assembly, the auxiliary valve assembly, and the electromagnetically actuated pilot valve assembly, effectively avoiding the problem of fuel pressure fluctuation during oil circuit switching. Conventional systems are prone to sudden drops in oil pressure or instantaneous fluctuations during oil circuit switching. The present invention achieves a smooth transition between upstream and downstream oil circuits through a reasonable valve structure and control method, so that the fuel flow and pressure can remain stable during the switching process, significantly improving the engine's ignition success rate and stability.

[0019] (2) The present invention reduces the need for high-power electromagnetic coils, reduces the required electromagnetic force, and reduces the overall volume of the solenoid valve and the power consumption during electromagnetic actuation by adopting a composite control structure of a pilot valve and a main valve. In addition, the precise matching design between the moving iron core and the valve rod and the shock absorption measures of the present invention make the electromagnetic actuation process smoother and more efficient, extending the service life of the solenoid valve assembly. At the same time, through the rational design of the fluid channel and valve structure, the influence of the hydraulic pressure on the actuation of the solenoid valve is reduced, thereby achieving a lighter electromagnetic structure that meets the strict weight and volume requirements of aircraft engines.

[0020] (3) The present invention adopts the principles of fluid dynamics and improves the fuel flow efficiency by designing a conical structure and a small flow channel hole. This design allows the fluid to pass through at a higher speed when the main valve is open, thereby reducing the flow resistance and improving the fuel supply efficiency. This technical effect not only improves the engine performance, but also reduces fuel consumption, helping to achieve more economical flight. In addition, the one-way valve design adopted by the present invention ensures that the auxiliary oil circuit can respond quickly and provide stable oil supply when needed. The auxiliary valve assembly achieves one-way flow through a steel ball and spring structure, effectively preventing the reverse flow phenomenon. This design enhances the reliability of the system and ensures that a good fuel supply state can be maintained under complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 Schematic diagram of a multi-oil-circuit fuel system according to an embodiment of the present invention.

[0023] Figure 2 This is a schematic cross-sectional view of the pressure-smooth opening electromagnetic device of a multi-oil-circuit, multi-electric aircraft engine fuel system according to an embodiment of the present invention. In the figure, both the pilot valve and the main valve are in the open state.

[0024] Figure 3 Schematic diagram of the cross-sectional structure of the valve body base in an embodiment of the present invention.

[0025] Figure 4 1. A top view (A) and a cross-sectional view (B) of the main valve in an embodiment of the present invention.

[0026] Figure 5 Schematic diagram of the structure of the valve seat in an embodiment of the present invention, wherein (A) is an axonometric view, (B) is a right side view, and (C) is a sectional view.

[0027] Figure 6 Schematic diagram of the structure of the one-way valve seat in an embodiment of the present invention, wherein (A) is an axonometric view, (B) is a right side view, and (C) is a sectional view.

[0028] Figure 7 1. It is a right side view (A) and a cross-sectional view (B) of the ball holder in an embodiment of the present invention.

[0029] Figure 8 Schematic diagram of the structure of the electromagnetically actuated pilot valve assembly in an embodiment of the present invention.

[0030] Figure 9 It is a schematic diagram of the state in which the pilot valve is closed and the main valve is open in the electromagnetic device of the present invention.

[0031] Figure 10 It is a schematic diagram showing that the pilot valve and the main valve in the electromagnetic device of the present invention are both in a closed state.

[0032] Description of reference numerals:

[0033] 1-Upper housing, 2-Top cover, 3-Electromagnetic coil, 4-Fastening screw, 5-Coil mounting bracket, 51-Cylindrical base, 52-Bracket column, 53-Conical groove, 6-Valve body base, 61-Oil flow channel, 611-Upstream oil inlet section, 612-Downstream oil outlet section, 62-Main valve installation valve port, 621-Main oil outlet hole, 622-Main oil return hole, 63-Auxiliary valve installation valve port, 631-Auxiliary oil outlet hole, 632-Auxiliary oil return hole, 64-Baffle, 7-One-way valve seat, 71-First cavity, 72-Second cavity, 73-First oil hole, 74-Second oil hole, 75-Annular Sealing groove, 8-sealing ring, 9-auxiliary valve return spring, 10-ball holder, 101-conical groove, 102-spring seat, 11-sealing ring, 12-valve seat, 121-center through hole, 122-annular sealing groove, 13-steel ball, 14-main valve return spring, 15-main valve, 151-plate structure, 152-annular skirt, 153-conical surface structure, 154-sealing gasket accommodating groove, 155-center oil return hole, 156-oil hole, 16-sealing ring, 17-sealing gasket, 18-valve rod, 19-iron core return spring, 20-moving iron core, 21-sealing ring. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the implementation of the present invention clearer, the technical solutions in the embodiments of the present invention will be described in more detail below with reference to the drawings in the embodiments of the present invention. The described embodiments are part of the embodiments of the present invention, rather than all the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present invention, and should not be understood as limiting the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0035] The present invention aims to provide a pressure-smooth opening electromagnetic device suitable for the fuel system of a multi-oil-circuit and multi-electric aircraft engine. In combination with relevant theories of fluid mechanics, the present invention optimizes the design of the solenoid valve structure, adopts a staged control method for the pilot valve, main valve and auxiliary valve, reasonably distributes the fluid pressure, and uses the Bernoulli equation to calculate the fluid pressure during the valve opening and closing process. While reducing the electromagnetic force, the pressure of the multi-oil-circuit system can be smoothly opened, thereby reducing the demand for electromagnetic force, reducing the volume and weight of the electromagnetic structure, and improving the installation adaptability of the device and the operating stability of the aircraft engine system.

[0036] As a specific example, Figure 2 As shown, the pressure smooth opening electromagnetic device of the multi-oil circuit and multi-electric aircraft engine fuel system according to the embodiment of the present invention includes an upper shell 1, a top cover 2, an electromagnetic coil 3, a fastening screw 4, a coil mounting frame 5, a valve body base 6, a one-way valve seat 7, a sealing ring 8, a secondary valve return spring 9, a ball holder 10, a sealing ring 11, a valve seat 12, a steel ball 13, a main valve return spring 14, a main valve 15, a sealing ring 16, a sealing gasket 17, a valve rod 18, an iron core return spring 19, a moving iron core 20, a sealing ring 21 and other structural components.

[0037] In the embodiment of the present invention, the main structure of the valve body base 6 is as follows Figure 3 As shown, it is provided with an oil flow channel 61, a main valve mounting valve port 62 and an auxiliary valve mounting valve port 63, wherein: the oil flow channel 61 is provided with a partition 64 which divides it into an upstream oil inlet section 611 and a downstream oil outlet section 612; the main valve mounting valve port 62 is arranged at the top of the valve body base 6, and is a cylindrical structure extending in the height direction as a whole, and its bottom is provided with at least a main oil outlet hole 621 communicating with the upstream oil inlet section 611 and a main oil return hole 622 communicating with the downstream oil outlet section 612; the auxiliary valve mounting valve port 63 is a blind hole channel structure extending in the horizontal direction with one end closed and the other end open, and its side wall is provided with at least one auxiliary oil outlet hole 631 communicating with the upstream oil inlet section 611 and an auxiliary oil return hole 632 communicating with the downstream oil outlet section 612.

[0038] Preferably, the oil flow channel 61 extends in the horizontal direction and passes through the main body of the valve body base 6, one end of which is formed as an oil inlet end and the other end is formed as an oil outlet end. The oil inlet end is used to be connected to an upstream fuel pump or fuel regulator through a pipeline, and the oil outlet end is used to be connected to a downstream combustion chamber or fuel nozzle through a pipeline. The inner wall of the oil flow channel 61 is precisely machined and polished to reduce friction resistance during the flow of fuel, and its diameter is adjusted according to the fuel flow requirements to ensure that a stable fuel pressure is maintained under different working conditions.

[0039] In the embodiment of the present invention, the main valve return spring 14, the main valve 15 and other components constitute the main valve structure, such as Figure 2、 4 As shown, the main valve 15 is disposed within the main valve mounting port 62 and comprises a plate-like structural member 151 with an annular skirt 152. The annular skirt 152 forms a clearance fit with the circumferential sidewalls of the main valve mounting port 62, and its top surface is higher than the top surface of the plate-like structural member 151. The center of the bottom surface of the plate-like structural member 151 protrudes downward to form a conical structure 153 facing the main oil return hole 622. A downwardly recessed sealing gasket accommodating groove 154 is provided at the center of the top surface. A central oil return hole 155 is provided at the bottom of the groove, penetrating downwardly through the conical structure 153. The plate-like structural member 151 is also provided with a plurality of oil holes 156 extending through its top and bottom surfaces and distributed circumferentially. The main valve return spring 14 is mounted between the plate-like structural member 151 of the main valve 15 and the bottom wall of the main valve mounting port 62.

[0040] Preferably, the main valve return spring 14 adopts a variable cross-section design, in which the bottom coil diameter is larger than the top coil diameter and the overall structure is conical, so as to reduce the overall height of the spring while ensuring sufficient return force, reduce the axial size of the device, and provide a nonlinear elastic characteristic to provide a larger return force at the initial opening of the main valve 15, and reduce the return force when it is close to the fully open position, which helps to achieve a smoother oil circuit switching process.

[0041] In the embodiment of the present invention, the one-way valve seat 7, the sealing ring 8, the auxiliary valve return spring 9, the ball holder 10, the sealing ring 11, the valve seat 12, the steel ball 13 and other components constitute the auxiliary valve structure. Specifically, Figure 2 、 5 As shown in Figures 1 to 7, the valve seat 12 is arranged at an axial position corresponding to the partition 64, and is provided with a central through hole 121 extending axially along the channel. The channel space in front of it is connected to the auxiliary oil outlet hole 631; the steel ball 13, the ball holder 10, and the auxiliary valve return spring 9 are arranged in the inner cavity 71 and 72 of the one-way valve seat 7 in sequence; the top of the one-way valve seat 7 is against the rear end surface of the valve seat 12, and there is a radial gap between its front end side wall and the inner wall of the channel and is connected to the auxiliary oil return hole 632, and a plurality of oil holes 73 and 74 are provided on its front end side wall, and its rear end side wall is sealed and fixedly arranged on the auxiliary valve mounting valve port 63.

[0042] Preferably, at least one annular sealing groove 75 is provided on the outer peripheral surface of the one-way valve seat 7, and a sealing ring 8 is installed in the annular sealing groove 75 to achieve sealing between the one-way valve seat 7 and the blind hole channel of the auxiliary valve mounting valve port 63; and, an external thread is also provided on the outer peripheral surface of the one-way valve seat 7, and an internal thread is provided on the inner wall of the blind hole channel of the auxiliary valve mounting valve port 63, and the one-way valve seat 7 and the blind hole channel of the auxiliary valve mounting valve port 63 are fixedly connected by threads. In addition, the inner cavity of the one-way valve seat 7 is formed into a stepped structure, which includes at least a first cavity 71 with a larger inner diameter arranged near its top and a second cavity 72 with a smaller inner diameter arranged near its end, wherein the ball holder 10 is arranged in the first cavity 71 in a manner that can slide left and right in the axial direction, and its front end face is processed into a conical groove 101 to support the steel ball 13 to ensure that the steel ball 13 maintains a stable position when the oil pressure changes, and its rear end face is processed into a spring seat 102; the main body of the auxiliary valve reset spring 9 is arranged in the second cavity 72, its top rests on the rear end face of the ball holder 10, and the end rests on the bottom wall of the second cavity 72 to provide a reset force when the steel ball is pressed and moved. Further preferably, a first oil hole 73 is provided on the front end side wall of the first cavity 71 of the one-way valve seat 7, which is used to guide the fuel into the first cavity 71 during the movement of the ball holder 10, and a second oil hole 74 is provided on the front end side wall of the second cavity 72, which is used to discharge the fuel when the auxiliary valve reset spring 9 is under pressure, thereby reducing the influence of back pressure on the reset action.

[0043] Preferably, at least one annular sealing groove 122 is provided on the outer peripheral surface of the valve seat 12, and a sealing ring 11 is installed in the annular sealing groove 122 to achieve sealing between the valve seat 12 and the blind hole channel of the auxiliary valve mounting valve port 63; and, the central through hole 121 of the valve seat 12 is configured as a conical expansion structure to reduce the flow resistance of the fuel when it enters the central through hole 121, and to reduce the generation of turbulence and bubbles by guiding the fuel to flow smoothly into the through hole.

[0044] In the embodiment of the present invention, the sealing gasket 17, the valve rod 18, the iron core return spring 19, and the moving iron core 20 constitute the pilot valve structure, and the top cover 2, the coil assembly 3, the coil mounting frame 5, the sealing ring 21, etc. constitute the electromagnetic actuation structure. Specifically, Figure 2 、 8 As shown, the electromagnetically actuated pilot valve assembly is installed on the top of the valve body base 6. The pilot valve includes at least a valve rod 18 and a sealing gasket 17. The upper end of the valve rod 18 is fixedly connected to the end of the moving iron core 20. The sealing gasket 17 is fixedly arranged at the lower end of the valve rod 18 and is used to cooperate with the sealing gasket receiving groove 154 at the top of the main valve 15 to form a seal; the moving iron core 20 drives the valve rod 18 to move axially through the energization operation of the electromagnetic coil, and when the electromagnetic coil is de-energized, the moving iron core 20 and the valve rod 18 are pushed back to the initial position by the reset spring.

[0045] The electromagnetically actuated pilot valve assembly is also provided with an electromagnetic coil assembly, which includes at least a top cover 2, an electromagnetic coil 3 and a coil mounting frame 5, wherein: the coil mounting frame 5 includes at least a cylindrical base 51 and a bracket column 52 formed at the center of the top surface of the cylindrical base 51 and extending axially upward, the inner circumferential wall of the cylindrical base 51 is provided with an internal thread and is fixedly arranged on the outer circumferential wall of the main valve mounting valve port 62 by a threaded connection, and the inner circumferential wall of the cylindrical base 51 is provided with an annular sealing groove and a sealing ring 21 to achieve sealing between the cylindrical base 51 and the main valve mounting valve port 62; the electromagnetic coil 3 is axially sleeved and mounted on the bracket column 52, and the top cover 2 is threadedly connected and fixedly arranged on the top of the bracket column 52 to achieve axial constraint on the top of the electromagnetic coil 3.

[0046] Preferably, the bracket column 52 of the coil mounting frame 5 is a hollow cylindrical structure with an open top as a whole, and the bottom of the cylindrical inner cavity is processed to form a conical groove 53, and the bottom wall of the conical groove 53 is provided with a valve rod through hole extending downward and passing through the cylindrical base 51; the moving iron core 20 is accommodated in the cylindrical inner cavity in a manner that can slide up and down in the axial direction, and a step structure for supporting the iron core return spring 19 is provided on its side wall, and the other end of the iron core return spring is against the top surface of the conical groove; and the end of the moving iron core 20 is processed to form a conical surface structure, which is adapted to the conical surface of the conical groove and an air gap is formed between the two to realize the axial movement of the moving iron core 20; a threaded connection hole is provided at the center of the conical structure of the moving iron core 20, and the valve rod 18 passes upward through the valve rod through hole and is threadedly fixed to the end of the moving iron core 20. In addition, the moving iron core 20 and the cylindrical inner cavity of the support column 52 of the coil mounting frame 5 are preferably clearance-fitted, with a diameter clearance range of Φ0.005mm to Φ0.015mm and a coaxial error range of Φ0.01mm to Φ0.03mm, which plays an axial centering role.

[0047] As an example, the electromagnetic device of the present invention further comprises an upper shell 1. Figure 2 As shown, a through hole is provided at the lower end of the upper shell 1, and a threaded hole is provided at the corresponding position of the coil mounting frame 5. The through hole and the threaded hole are connected by fastening screws 4 to achieve fixation between the upper shell 1 and the coil mounting frame 5.

[0048] The following combination Figure 2 、 9 10. The working principle of the pressure smooth opening electromagnetic device of the multi-oil circuit multi-electric aircraft engine fuel system provided by the embodiment of the present invention is described as follows:

[0049] When the system requires fuel switching or pressure adjustment, the solenoid coil in the electromagnetically actuated pilot valve assembly is energized, driving the movable iron core axially. This iron core, via the valve rod, opens or closes the pilot valve. Under the influence of electromagnetic force, the pilot valve controls the oil flow path of the main valve assembly, ensuring smooth opening and closing of the main valve. During this process, the pilot valve regulates the fuel pressure entering the main valve, ensuring that it is not subjected to sudden pressure surges when opening, thereby maintaining fuel system stability. The main valve moves in response to pressure differentials, and its annular skirt and conical surface precisely control the fuel flow rate. A central oil return port ensures fast response and precise adjustment. The auxiliary valve assembly, located downstream of the oil flow path, acts as a check valve. When the system oil pressure reaches a specific value, the auxiliary valve opens, alleviating the pressure differential between upstream and downstream, assisting the main valve assembly in achieving smooth switching. The auxiliary valve's steel ball and return spring work together to ensure rapid response and reset in response to pressure changes, effectively preventing fuel backflow and uneven pressure within the system. The return springs on both the main and auxiliary valves ensure that in the event of a power outage or abnormal condition, the valves quickly return to a safe position, ensuring system safety. Precise control of the main valve and the auxiliary valve's assistance ensure smooth switching of the fuel circuit and smooth pressure release, avoiding sudden pressure fluctuations. The coordinated control of the main, pilot, and auxiliary valves ensures smooth and rapid response and adjustment of the fuel system under varying operating conditions, ensuring stable and efficient engine operation.

[0050] More specifically, the operating principle of the electromagnetic device for smooth pressure opening of the fuel system of a multi-fuel-circuit, multi-electric aircraft engine according to an embodiment of the present invention can be divided into four stages, covering the entire process from engine starting to fuel circuit closing. The specific process of each stage and the physical principles behind it are described in detail below:

[0051] Phase 1: Engine Startup and Initial Fuel Supply. During the starting and ignition phase of a multi-fuel, multi-electric engine, the system first activates the two-way solenoid valve. Once energized, the electromagnetically actuated pilot valve presses against the main valve 15, forming a seal with the valve body base 6. The high-pressure pump then starts operating, and fuel is supplied to the combustion chamber via the first line. The key to this phase is ensuring stable fuel flow to the combustion chamber for smooth engine ignition. By precisely controlling the opening of the solenoid valves, the system ensures a continuous and stable fuel supply during the initial phase, effectively avoiding the oil pressure fluctuations that can occur during fuel switching in traditional systems. According to the basic principles of fluid dynamics, when the high-pressure pump is operating, the fuel pressure within the system rises rapidly, laying the foundation for the smooth progress of subsequent phases.

[0052] Phase 2: System Speed ​​Increases and Auxiliary Valve Opening. As engine speed increases, the system's fuel pressure, P0, rises. When the pressure reaches a preset threshold, the two auxiliary valves open, allowing some fuel to flow out through the valves, thereby regulating the pressure differential within the system. During this process, a pressure differential, ΔP, forms between the upper and lower surfaces of the main valve 15. This pressure differential ensures smooth fuel flow within the system and balances upstream and downstream pressures, paving the way for subsequent pressure regulation and valve switching. By properly opening the auxiliary valves, the system maintains smooth fuel flow as speed increases, ensuring continuous engine ignition and stable operation.

[0053] Stage 3: Successful combustion chamber ignition and opening of the main valve. When the two combustion chamber nozzles successfully ignite, the two solenoid valves are de-energized. The core return spring forces the moving core 20 upward. With the release of the electromagnetic force, the pilot valve resets, and the small flow channel in the main valve opens, gradually reducing the pressure differential ΔP between the upper and lower surfaces of the main valve 15 to zero. The elastic potential energy of the main valve return spring 14 is released, pushing the main valve 15 open. The main flow channel is now fully open, ensuring near-consistency between the inlet and outlet pressures. The auxiliary valve then automatically closes, completing a smooth transition from the auxiliary fuel line to the main fuel line. This process ensures continuity and stability in fuel flow into the combustion chamber while avoiding fuel flow instability caused by sudden pressure differential changes. The control logic in this stage, through the coordinated cooperation of the pilot valve and the main valve, enables the system to smoothly transition to the main fuel supply state after combustion chamber ignition.

[0054] Phase 4: Oil circuit closure and resealing of the main valve. When the flight mission requires closing the two oil circuits, the solenoid valve is energized again. The pilot valve moves downward, sealing the small flow channel in the middle of the main valve 15, thereby sealing the flow channel of the main valve. After the pilot valve I closes, the fluid flows through the main channel. Because the effective area of ​​fuel flow near the main channel valve is distributed in an annular shape along the flow path, the fuel flow rate at the valve port increases. According to Bernoulli's principle, the pressure decreases accordingly. This pressure drop further assists in closing the main valve, forming a positive feedback mechanism. This design reduces the reliance on electromagnetic force, eliminating the need for additional electromagnetic force during the system closing process, and improving the system's energy efficiency.

[0055] A key feature of the present invention is its ability to significantly reduce the electromagnetic force required. To do this, the present invention utilizes the Bernoulli equation in fluid mechanics. Ignoring viscous losses, the flow of fuel in the fuel supply pipeline can be approximated as an ideal fluid, following the Bernoulli equation:

[0056]

[0057] When the solenoid valve is energized, the electromagnetic force pushes the pilot valve to close. When the fuel flows out from the main channel, the annular distribution of the flow channel increases the flow velocity v2 and reduces the pressure P2. There is a large pressure difference between the upper and lower surfaces of the main valve 15. The large liquid pressure will further promote the closing of the main valve without the need for a larger electromagnetic force.

[0058] In the present invention, the entire device achieves stable switching and pressure regulation of the fuel system in multi-oil and multi-electric aircraft engines through the coordinated control of multi-stage valves and electromagnetic actuators. The collaboration of the pilot valve, main valve, and auxiliary valve ensures a smooth transition of fuel pressure under different operating conditions. In particular, through the precise control of the electromagnetically actuated pilot valve, the up and down movement of the moving iron core can quickly respond to system requirements and timely control the opening and closing of the fuel flow channel in the power-on and power-off states. In addition, the auxiliary valve assembly automatically opens when the system pressure exceeds a certain threshold, and the one-way valve structure balances the upstream and downstream pressure differences, allowing the system to maintain stable operation under high pressure and high load conditions.

[0059] Furthermore, the precise fit between the electromagnetic coil and the movable iron core ensures system stability during operation. The clearance between the movable iron core and the valve rod, along with the optimized design of components such as the ball holder and steel ball, ensures stable operation of the entire system under normal operating pressure while maintaining low friction and wear even under high pressure.

[0060] In summary, the operating principle of this invention achieves efficient and smooth switching of a multi-fuel, multi-electric aircraft engine fuel system through precise control of multi-stage valves and electromagnetic actuation. It also utilizes the principles of fluid mechanics to optimize electromagnetic force requirements and ensure system safety and stability under high-pressure conditions.

[0061] The above description is merely a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modifications, variations, and equivalent structural changes made to the above embodiment based on the technical essence of the present invention remain within the scope of protection of the technical solution of the present invention. It has a wide range of applications, adapts to various hydraulic working conditions, and has reliable performance.

Claims

1. A pressure-smooth opening electromagnetic device for a multi-fuel-circuit, multi-electric aircraft engine fuel system, comprising at least a valve body base, a main valve assembly, a secondary valve assembly, and an electromagnetically actuated pilot valve assembly, characterized in that: The valve body base is provided with an oil flow channel, a main valve mounting valve port and an auxiliary valve mounting valve port, wherein: the oil flow channel is provided with a partition plate that divides it into an upstream oil inlet section and a downstream oil outlet section; the main valve mounting valve port is arranged at the top of the valve body base, and is a cylindrical structure extending in the height direction as a whole, and its bottom is provided with at least one main oil outlet hole communicating with the upstream oil inlet section and one main oil return hole communicating with the downstream oil outlet section; the auxiliary valve mounting valve port is a blind hole channel structure extending in the horizontal direction with one end closed and the other end open, and its side wall is provided with at least one auxiliary oil outlet hole communicating with the upstream oil inlet section and one auxiliary oil return hole communicating with the downstream oil outlet section; The main valve assembly comprises at least a main valve and a main valve return spring, the main valve being arranged in the main valve mounting valve port, and being a plate-like structural member with an annular skirt as a whole, the annular skirt forming a clearance fit with the circumferential side wall of the main valve mounting valve port, and its top surface being higher than the top surface of the plate-like structural member; the center of the bottom surface of the plate-like structural member protrudes downward to form a conical structure facing the main oil return hole, the center of the top surface is provided with a downwardly concave sealing gasket accommodating groove, the bottom of the groove is provided with a central oil return hole penetrating downwardly through the conical structure, and the plate-like structural member is further provided with a plurality of oil holes penetrating its top and bottom surfaces and distributed circumferentially; the main valve return spring is installed between the plate-like structural member of the main valve and the bottom wall of the main valve mounting valve port; The auxiliary valve assembly is formed as a one-way valve as a whole, comprising at least a valve seat, a steel ball, a ball holder, a secondary valve return spring and a one-way valve seat arranged axially along the blind hole channel of the auxiliary valve mounting valve port, wherein: the valve seat is arranged at an axial position corresponding to the partition plate, and is provided with a central through hole extending axially along the channel, and the channel space in front of the valve seat is communicated with the auxiliary oil outlet hole; the steel ball, the ball holder and the auxiliary valve return spring are sequentially arranged in the inner cavity of the one-way valve seat; the top of the one-way valve seat is against the rear end surface of the valve seat, and a radial gap is formed between the front end side wall and the inner wall of the channel and is communicated with the auxiliary oil return hole, and a plurality of oil holes are provided on the front end side wall, and the rear end side wall is sealed and fixedly arranged on the auxiliary valve mounting valve port; The electromagnetically actuated pilot valve assembly is installed on the top of the valve body base, and includes at least a moving iron core driven by an electromagnetic coil and a spring-reset pilot valve. The pilot valve includes at least a valve rod and a sealing gasket. The upper end of the valve rod is fixedly connected to the end of the moving iron core, and the sealing gasket is fixedly arranged at the lower end of the valve rod, and is used to cooperate with the sealing gasket receiving groove at the top of the main valve to form a seal; the moving iron core drives the valve rod to move axially through the power-on operation of the electromagnetic coil, and the reset spring pushes the moving iron core and the valve rod back to the initial position when the electromagnetic coil is de-energized.

2. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 1, characterized in that: The oil flow channel extends horizontally and passes through the main body of the valve body base, with one end forming an oil inlet end and the other end forming an oil outlet end. The oil inlet end is used to be connected to an upstream fuel pump through a pipeline, and the oil outlet end is used to be connected to a downstream combustion chamber or fuel nozzle through a pipeline. The inner wall of the oil flow channel is precisely machined and polished to reduce frictional resistance during the flow of fuel, and its diameter is adjusted according to the fuel flow requirements.

3. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 1, characterized in that: The main valve return spring adopts a variable cross-section design, with the bottom coil diameter being larger than the top coil diameter and the overall conical structure, so as to reduce the overall height of the spring while ensuring sufficient return force, reduce the axial size of the device, and provide nonlinear elastic characteristics. It provides a larger return force at the initial opening of the main valve, and reduces the return force when it approaches the fully open position, which helps to achieve a smoother oil circuit switching process.

4. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 1, characterized in that: At least one annular sealing groove is provided on the outer circumferential surface of the one-way valve seat, and a sealing ring is installed in the annular sealing groove to achieve sealing between the one-way valve seat and the blind hole channel of the auxiliary valve mounting valve port; and, an external thread is also provided on the outer circumferential surface of the one-way valve seat, and an internal thread is provided on the inner wall of the blind hole channel of the auxiliary valve mounting valve port, and the one-way valve seat and the blind hole channel of the auxiliary valve mounting valve port are fixedly connected by threads.

5. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 1, characterized in that: The inner cavity of the one-way valve seat is formed into a stepped structure, which includes at least a first cavity with a larger inner diameter arranged near its top and a second cavity with a smaller inner diameter arranged near its end, wherein the ball holder is arranged in the first cavity in a manner that can slide left and right in the axial direction, and its front end surface is processed into a conical groove to support the steel ball to ensure that the steel ball maintains a stable position when the oil pressure changes, and its rear end surface is processed into a spring seat; the main body of the auxiliary valve return spring is arranged in the second cavity, its top rests on the rear end surface of the ball holder, and the end rests on the bottom wall of the second cavity to provide a return force when the steel ball is pressed and moved.

6. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 5, characterized in that: A first oil hole is provided on the front end side wall of the first cavity of the one-way valve seat, which is used to guide the fuel into the first cavity during the movement of the ball holder. A second oil hole is provided on the front end side wall of the second cavity, which is used to discharge the fuel when the auxiliary valve return spring is under pressure, thereby reducing the influence of back pressure on the return action.

7. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 1, characterized in that: At least one annular sealing groove is provided on the outer peripheral surface of the valve seat, and a sealing ring is installed in the annular sealing groove to achieve sealing between the valve seat and the blind hole channel of the auxiliary valve mounting valve port; and the central through hole of the valve seat is set to a conical expansion structure to reduce the flow resistance of the fuel when it enters the central through hole and reduce the generation of turbulence and bubbles.

8. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 1, characterized in that: The electromagnetically actuated pilot valve assembly is also provided with an electromagnetic coil assembly, and the electromagnetic coil assembly includes at least a top cover, an electromagnetic coil and a coil mounting frame, wherein: the coil mounting frame includes at least a cylindrical base and a bracket column formed at the center of the top surface of the cylindrical base and extending axially upward, the inner circumferential wall of the cylindrical base is provided with an internal thread and is fixedly arranged on the outer circumferential wall of the main valve mounting valve port by a threaded connection, and the inner circumferential wall of the cylindrical base is provided with an annular sealing groove and a sealing ring to achieve sealing with the main valve mounting valve port; the electromagnetic coil is axially sleeved and mounted on the bracket column, and the top cover is threadedly connected and fixedly arranged on the top of the bracket column to achieve axial constraint on the top of the electromagnetic coil.

9. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 8, characterized in that: The bracket column of the coil mounting frame is a hollow cylindrical structure with an open top. The bottom of the cylindrical inner cavity is processed into a conical groove, and a valve rod through hole extending downward and passing through the cylindrical base is provided on the bottom wall of the conical groove; the moving iron core is accommodated in the cylindrical inner cavity in a manner that can slide up and down in the axial direction, and a step structure for supporting the iron core return spring is provided on its side wall, and the other end of the iron core return spring is against the top surface of the conical groove.

10. The pressure-smooth opening electromagnetic device for a multi-oil-circuit, multi-electric aircraft engine fuel system according to claim 9, characterized in that: The end of the moving iron core is processed into a conical structure, which is adapted to the conical surface of the conical groove and an air gap is formed between the two to realize the axial movement of the moving iron core; a threaded connection hole is provided at the center of the conical structure of the moving iron core, and the valve rod passes upward through the valve rod through hole and is threadedly fixed to the end of the moving iron core.

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