CN109469594B - Continuous pressure regulating electro-hydraulic proportional axial plunger variable pump for aircraft hydraulic system - Google Patents

Abstract

The invention relates to a continuous pressure regulating electro-hydraulic proportional axial plunger variable pump for an aircraft hydraulic system, which comprises: proportion electromagnet: the electromagnetic suction is provided and acts with the hydraulic pressure of the pressure regulating mechanism together to realize the continuous change of the opening degree of the valve port of the regulating mechanism; two-position three-way electromagnetic directional valve: the switching between two states of two-stage voltage regulation and continuous voltage regulation is realized; the pressure regulating mechanism: the hydraulic oil pump moves under the combined action of spring force, hydraulic pressure and electromagnet suction, and communicates a follow-up piston pressure cavity to be connected with return oil or a high-pressure oil cavity; all the variable head are arranged in the variable head, the mounting position of the variable head is fixed through a bottom plug, the variable head is fixed with the plunger pump through a bolt, and an oil way of the variable head is connected with an oil way related to the pump. The continuous pressure regulating electro-hydraulic proportional axial plunger variable displacement pump realizes continuous regulation from the lowest working pressure to the highest working pressure, and keeps a double-stage pressure regulating function, thereby ensuring the safe operation of the system.

Description

Continuously Regulating Electro-hydraulic Proportional Axial Piston Variable Pump for Aircraft Hydraulic System

technical field

The invention relates to the field of hydraulic control equipment, in particular to a continuously regulated electric-hydraulic proportional axial plunger variable pump used in an aircraft hydraulic system.

Background technique

The aircraft hydraulic actuation system is developing towards high pressure and high power. The existing aircraft hydraulic system generally requires the axial piston pump to work in a constant pressure variable mode to achieve constant pressure source oil supply. Due to the large change of load pressure in the entire flight profile, the traditional fixed pressure constant pressure variable pump has problems such as large throttling loss and difficulty in heat dissipation. The temperature rises sharply, which affects its normal operation.

For the existing airborne hydraulic system, the working efficiency of the actuator is relatively higher than that of the system pump source, and most of the power loss is generated by the pump source or is closely related to the working form of the pump source. The country is developing variable pressure on-board hydraulic systems, and proposes two types of pump sources for on-board hydraulic systems, dual-variable variable pumps and intelligent pumps.

Two-stage pressure variable pump adopts two-stage variable pump. When high pressure is required, the pump source works in a high-pressure variable state; others work in a low-pressure variable state. This will partially reduce the reactive power loss due to increased system pressure. When the required pressure value falls between high and low pressure, the required pressure should still be close to the high pressure regulation, which will generate more power loss and generate a large amount of heat like the aforementioned on-board hydraulic pump source. The intelligent pump source system, the core of which is a variable pump controlled by a microprocessor, can realize a variety of functions, and forms an intelligent system in the form of upper and lower computers with the aircraft main control computer system, and realizes four working modes of flow, pressure, power and integration. It is the most ideal pump source system today. However, this kind of pump source system has high cost requirements and has not been put into practical use.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the problem of large power loss caused by the constant pressure variable mode of the existing airborne hydraulic system. On the basis of the two-stage pressure variable pump, a pump outlet pressure can be continuously adjusted between the lowest and the highest working pressure. The electro-hydraulic proportional variable pump.

In order to achieve the above object, technical scheme of the present invention is as follows:

Continuously regulated electro-hydraulic proportional axial plunger variable pump for aircraft hydraulic system, including: axial plunger pump and variable head, variable head and plunger pump are fixed together by bolts, variable head upper oil circuit and plunger The pump oil circuit is connected; the axial piston pump includes a pump casing and a maximum displacement limit mechanism, a drive shaft, a plunger, a cylinder block, a distribution plate, a swash plate, and the variable head assembled in the pump casing. Proportional electromagnet, two-position three-way electromagnetic reversing valve and pressure regulating mechanism are installed inside, and there is an internal processing oil circuit for the oil demand of internal parts. The proportional electromagnet is installed on the two-position three-way electromagnetic reversing mechanism. Under the same side of the valve, the adjustment mechanism is located at the same horizontal position of the proportional electromagnet;

The proportional electromagnet is placed in the variable head hole, with internal threads processed in the hole, and the position of the proportional electromagnet is fixed with a plug; as an electro-mechanical conversion element, the obtained electrical signal is converted into a force signal, and its output force is related to the adjustment mechanism. Hydraulic pressure comparison, control the size of the spool orifice, adjust the flow into the variable cylinder, adjust the inclination of the swash plate, and thus adjust the output pressure of the variable pump;

The two-position three-way electromagnetic reversing valve is installed in the hole processed by the variable head. The bottom of the hole is machined with internal threads. The position of the two-position three-way electromagnetic reversing valve is fixed with a plug. Connect the oil outlet of the variable pump, the oil chamber of the spring base of the pressure regulating mechanism and the regulating chamber of the variable pump; among them, when the electromagnet of the two-position three-way electromagnetic reversing valve is energized, it pushes its spool to move, connecting the oil outlet of the variable pump and the adjusting chamber of the variable pump. Press the spring base oil chamber of the mechanism, continue to compress the spring until it reaches the limit device, and realize the two-stage pressure adjustment of the variable pump. On this basis, the proportional electromagnet is energized to realize the continuous pressure adjustment. Electric, variable pump work in low pressure state, two-stage pressure and continuous pressure regulation are invalid;

The pressure regulating mechanism includes a pressure regulating spring, a spring base, a limit mechanism, a regulating valve core, and the regulating valve core is connected with the push rod of the proportional electromagnet, and the proportional electromagnet converts the current signal obtained through the proportional amplifier board into an output force; The mechanism is installed in the variable head, and the bottom is machined with internal threads. The pre-tightening force of the pressure regulating spring is adjusted through the plug. It moves under the combined action of the spring force, the output force of the proportional electromagnet and the hydraulic pressure, and communicates the pressure chamber of the follower piston with the return. The oil phase connection or the communication follower piston is connected with the high pressure oil chamber, so that the inclination angle of the oil pump swash plate increases or decreases, and then the output flow rate of the electro-hydraulic proportional axial piston variable pump increases or decreases; the pressure regulating mechanism Determines the outlet pressure of the electro-hydraulic proportional axial piston variable pump, the low pressure value of the pressure regulating mechanism is set by adjusting the preload of the pressure regulating spring, and the high pressure value is set by the pressure regulating spring and the system hydraulic pressure; In the mounting hole of the pressure regulating mechanism, a boss is processed to limit the stroke of the spring seat of the pressure regulating mechanism and prevent the failure of the spring from excessive compression, thereby realizing two-stage compression of the spring.

Further, the nine plungers in the plunger pump are evenly placed inside the cylinder body of the continuous hydraulic proportional axial piston variable pump, which is connected with the drive shaft through splines, and the valve plate is fixed on the continuous hydraulic proportional shaft. On the piston variable pump cylinder body, with the external input torque, the cylinder body of the continuously regulated electro-hydraulic proportional axial piston variable pump is driven to rotate, and the piston reciprocates linearly under the restriction of the return mechanism, thereby realizing the pressure output of the oil pump. ; When the plunger moves in the direction away from the cylinder, the oil is sucked from the oil suction port through the distribution plate, and the high-pressure oil is transported to the hydraulic pipeline from the oil outlet through the distribution plate when the plunger moves in the direction of the cylinder.

Further, the electromagnet of the two-position three-way electromagnetic reversing valve is energized to make it work in a two-stage pressure regulating state, and then the proportional electromagnet is energized to generate a thrust corresponding to the current size, so that the thrust of the electromagnet and the outlet pressure of the oil pump act on the valve. The sum of the force on the core is equal to the force of the spring, so with the change of the voltage applied to the proportional electromagnet, the outlet pressure of the oil pump changes accordingly.

Further, because the outlet pressure of the oil pump is equal to the spring force minus the thrust of the electromagnet, the pressure of the oil pump gradually decreases with the increase of the thrust of the proportional valve, that is, the input voltage; the outlet pressure of the oil pump changes continuously between the maximum output pressure and the minimum output pressure.

Further, when the proportional electromagnet fails, that is, the continuously variable suction cannot be output, the outlet pressure of the continuously regulated electro-hydraulic proportional axial piston variable pump acts on the pressure regulating mechanism, which is compared with the spring force, so through the two-position three-way The switching of the solenoid valve can realize two-stage compression of the spring and two-stage pressure change. With the continuous adjustment of the pressure at the outlet of the hydraulic proportional axial piston variable pump, two-stage adjustment can be realized.

Further, when the electromagnet of the two-position three-way electromagnetic reversing valve is de-energized, the system works under the lowest pressure working state, and the two-stage pressure regulation function can be realized when the power is turned on.

Aiming at the problem of a large amount of power loss caused by the constant pressure variable mode of the airborne hydraulic system, the present invention proposes a continuous pressure regulating proportional variable pump, which can adapt to the load pressure demand and can effectively reduce the power loss and heating problems. The realization method is as follows:

The essence of the continuous regulating electro-hydraulic proportional variable pump is to introduce the electro-hydraulic proportional technology on the basis of the two-stage pressure regulating variable pump. When the proportional electromagnet of the electromagnetic reversing valve is energized, the output oil of the pump is introduced into the oil chamber of the spring base of the adjustment mechanism, and the spring base is pushed to compress until it hits the limit mechanism, thereby realizing the two-stage compression of the spring, so The pressure at the oil outlet of the variable pump increases to realize two-stage pressure regulation;

When the proportional electromagnet of the two-position three-way electromagnetic reversing valve is energized, the output force of the proportional electromagnet, the spring force and the hydraulic pressure act on the spool of the adjustment mechanism at the same time, and the proportional electromagnet and the hydraulic pressure act on the spool of the adjustment mechanism. The force direction is the same, so as the input current of the proportional electromagnet increases, that is, the output force increases, the output pressure of the variable pump decreases.

When the energized current of the proportional electromagnet is not zero, the force on the valve core of the regulating mechanism is expressed as

Ignoring the description of its damping term and inertia term, it can be obtained that the spool displacement x ₀ increases when the output force F ₀ of the proportional electromagnet increases, so the flow into the regulating cylinder increases, which reduces the inclination of the swash plate and reduces the pressure.

In the case of a sudden failure of the proportional electromagnet, it can be restored to the two-stage pressure regulation mode, that is, the two-stage pressure regulation function of the original pump is not damaged.

Beneficial effects: the continuous regulation of the outlet pressure of the electro-hydraulic proportional axial piston variable pump of the present invention can realize continuous regulation between the highest working pressure and the lowest working pressure of the two-stage pressure regulating pump, and in the case of failure of the proportional electromagnet, the The two-stage voltage regulation function ensures the normal operation of the system.

Description of drawings

FIG. 1 is a schematic structural diagram of a continuous pressure regulating proportional variable pump according to an embodiment of the present invention.

FIG. 2 is a working principle diagram of a continuous pressure regulating proportional variable pump according to an embodiment of the present invention.

FIG. 3 is a working principle diagram of a comparative embodiment of the present invention.

In the figure, 1-two-position three-way electromagnetic reversing valve, 2-adjustment mechanism, 3-pressure regulating spring, 4-axial piston pump 5-adjustment chamber 6-proportional electromagnet, 7-oil suction port, 8-outlet Oil port, 9-axial piston variable pump outlet, 10-variable head, 11-maximum displacement limit mechanism, 12-drive shaft, 13-piston, 14-cylinder, 15-distribution plate, 16-inclined Disc, 17- proportional pressure reducing valve, 18- two-position two-way electromagnetic reversing valve, 19- regulating valve spool, 20- additional regulating spool, 21- push rod, 22- return spring.

Detailed ways

The principle diagram of a continuously regulated electro-hydraulic proportional axial piston variable pump for an aircraft hydraulic system proposed by the present invention is shown in Fig. 1 and Fig. 2 is a structural diagram thereof.

The continuously regulated electro-hydraulic proportional axial piston variable pump used in the aircraft hydraulic system, as shown in Figure 1, includes an axial piston pump 4 and a variable head 10, and the variable head 10 and the axial piston pump 4 are fixed by bolts Together, the upper oil circuit of the variable head 10 is connected with the oil circuit of the axial piston pump 4; the axial piston pump 4 includes a pump casing and a maximum displacement limiting mechanism 11 assembled in the pump casing, a drive shaft 12. Plunger 13, cylinder 14, valve plate 15, swash plate 16, wherein:

The variable head 10 includes a two-position three-way electromagnetic reversing valve 1, a proportional electromagnet 6 installed under the same side of the two-position three-way electromagnetic reversing valve 1, and an adjusting mechanism located at the same horizontal position and communicating with the proportional electromagnet 6. 2, and there is an internal processing oil circuit; the pressure regulating mechanism 2 includes a pressure regulating spring 3, a spring base, a limit mechanism, and a regulating valve core, and a boss is processed in the installation hole for the mechanical limit of the spring base to prevent the spring from being excessive In the case of compression failure, two-stage compression of the spring is realized, the regulating valve core is connected with the push rod of the proportional electromagnet, and the proportional electromagnet 6 converts the current signal obtained by the proportional amplifier board into the output force; the two-position three-way electromagnetic directional valve 1 and There are plugs at the bottom of the proportional electromagnet 6 to limit its position; wherein, the oil ports of the two-position three-way electromagnetic reversing valve 1 are respectively connected to the spring base oil cavity of the pressure regulating mechanism 2 through the oil pipeline in the variable head 10 , the oil outlet 8 of the axial piston pump 4 and the adjustment chamber 5 of the axial piston pump 4; the proportional electromagnet 6 converts the obtained electrical signal into a force signal, and its output force is compared with the hydraulic pressure of the adjustment mechanism 2 , control the size of the spool orifice, adjust the flow into the axial piston pump 4, adjust the inclination of the swash plate 16, so as to adjust the output pressure of the axial piston variable pump outlet 9; the pressure regulating mechanism 2 is adjusted by the plug The pre-tightening force of the pressure regulating spring 3, which moves under the combined action of the spring force, the output force of the proportional electromagnet 6 and the hydraulic pressure, connects the pressure chamber of the follower piston with the oil return or the follower piston is connected with the high pressure oil chamber, The inclination angle of the oil pump swash plate 16 is increased or decreased, and then the output flow of the electro-hydraulic proportional axial piston variable pump increases or decreases; the pressure regulating mechanism 2 determines the pressure at the outlet 9 of the electro-hydraulic proportional axial piston variable pump , the low pressure value of the pressure regulating mechanism 2 is set by adjusting the pre-tightening force of the pressure regulating spring 3, while the high pressure value is set by the pressure regulating spring 3 and the system hydraulic pressure. In the present invention, a control system composed of an axial plunger pump 4, a proportional electromagnet 6, a two-position three-way electromagnetic reversing valve 1, and a regulating mechanism 2 is used to control the output flow of the oil pump accurately proportionally. Its working principle: When the two-position three-way electromagnetic reversing valve 1 is energized, it pushes its spool to move, connects the oil outlet 8 and the oil chamber of the spring base of the pressure regulating mechanism 2, and continues to compress the spring until it reaches the limit device, realizing the double variable pump. On this basis, the proportional electromagnet 6 is energized to realize continuous pressure adjustment. When the two-position three-way electromagnetic reversing valve 1 is de-energized, the variable pump works in a low pressure state, and the two-stage pressure and continuous pressure adjustment are invalid.

In the embodiment, under the working condition of the continuously regulated electro-hydraulic proportional axial piston variable pump, the aircraft engine is connected to the drive shaft 12 of the variable pump through the gearbox, and drives the cylinder block 14 spline-connected to the drive shaft 12 to rotate together; nine The plunger 13 is evenly installed in the cylinder 14 at the same angle. Driven by the return mechanism, it performs a reciprocating linear motion in the cylinder 14. When the plunger 13 moves in the direction away from the cylinder 14, it passes through the valve plate 15 from the oil suction port. 7. The oil is sucked in, and the plunger 13 moves in the direction of the cylinder block 14, and the high-pressure oil is transported to the hydraulic pipeline from the oil outlet 8 through the distribution plate 15.

When the two-position three-way electromagnetic reversing valve 1 is energized, but the proportional electromagnet 6 is not energized, the output oil of the variable pump is introduced into the oil chamber of the spring base of the adjustment mechanism 2, and the spring base is pushed to compress until it hits the limit mechanism. , thereby realizing the two-stage compression of the spring, so that the pressure of the variable pump oil outlet 8 is increased, and the pressure is adjusted in two stages; when the two-position three-way electromagnetic reversing valve 1 is energized, and the proportional electromagnet 6 is also energized, the proportional electromagnet is energized. 6. The output force, spring force and hydraulic pressure act on the valve core of the adjustment mechanism 2 at the same time. The proportional electromagnet 6 and the hydraulic pressure act in the same direction on the valve core of the adjustment mechanism 2. Therefore, as the input current of the proportional electromagnet 6 increases, the output As the force increases, the output pressure of the variable pump decreases.

The force of the valve core of the regulating mechanism is expressed as:

Ignoring the description of its damping term and inertia term, it can be obtained that the spool displacement x ₀ increases when the output force F ₀ of the proportional electromagnet increases, so the flow into the regulating cylinder increases, the inclination angle of the swash plate decreases, and the pressure of the variable pump decreases. displacement.

The control chamber pressure change equation is:

The change in the displacement of the spool causes the flow rate _QC entering the regulating cylinder, and therefore the pressure PC in the regulating _chamber changes.

The torque balance equation of the variable pump swash plate is:

Among them, I swash plate rotational inertia, C swash plate rotational viscous damping coefficient, F _C controls the force of the cylinder acting on the swash plate, F _n The force of the plunger acting on the swash plate adjusts the pressure change P _C causes the change F _C , which is given by This changes the inclination of the swashplate.

Variable pump output pressure equation:

where: Q _p =G _p α (5)

In this way, it can be obtained that the change of the inclination angle of the swash plate causes the change of the output flow, which in turn affects the size of the output pressure.

It can be obtained from the above derivation process that when the output force of the proportional electromagnet 6 changes with the input current, the displacement of the valve core of the regulating mechanism 2 can be changed, and the flow rate entering the pressure regulating chamber can be changed, causing its pressure to change, and then changing the inclination of the swash plate 16 of the variable pump. The flow rate and output pressure change accordingly. Therefore, there is a transformation relationship between the input current and the output pressure of the flow pump, and it is feasible to achieve continuous pressure change by changing the size of the continuously changing current.

Compared with the embodiment: the variable mechanism of the variable pump also includes a proportional pressure reducing valve 17 , a two-position two-way electromagnetic reversing valve 18 , a regulating valve core 19 , an additional regulating valve core 20 , a push rod 21 , and a return spring 22 . As shown in FIG. 3 , a T-shaped groove is processed on the push rod 21 and the external regulating valve core 20 , so as to connect the push rod 21 and the external regulating valve core 20 to improve the problem of unstable force transmission. When the two-position and two-way electromagnetic reversing valve 18 is not energized, the two-stage pressure regulating function can be realized; when the two-position and two-way electromagnetic reversing valve 18 is energized, the proportional pressure reducing valve 17 is supplied with current, thereby generating and The opening degree of the valve port corresponding to the magnitude of the current determines the size of the outlet pressure of the proportional pressure reducing valve 17, and the size of the force acting on the end area of the valve core 20 is also determined. The valve core of the pressure regulating mechanism 2 is subjected to the force of the external regulating valve core 20 due to the pressure of the pump outlet 9, the force of the push rod 21, and the force of the pressure regulating spring 3 to achieve force balance. The spring force of the valve core has been set, and the force of the push rod 21 changes with the input current of the proportional pressure reducing valve 17, so the pressure at the pump outlet 9 can change accordingly, so that the pressure at the pump outlet 9 can be between the highest working pressure and the lowest value of the dual variable pump. Continuous adjustment between working pressures.

The mechanical structure of this implementation method is relatively complex, and two oil circuits need to be formed to realize the functions of continuous pressure regulation and two-stage pressure regulation, and the design and processing of the variable head oil circuit is relatively complicated. It is more difficult to machine T-slots.

In comparison, the implementation in the present invention has a simpler mechanical structure, fewer components required, and lower cost; the variable head oil circuit design is simpler, and its processing is easy to implement, and the proportional electromagnet push rod does not require further processing.

Claims (6)

1. Continuously regulated electro-hydraulic proportional axial piston variable pump for aircraft hydraulic system, including: axial piston pump and variable head, the variable head and the piston pump are fixed together by bolts, and the oil circuit on the variable head is connected to the variable head. The plunger pump is connected to the oil circuit; it is characterized in that: the axial plunger pump includes a pump casing and a maximum displacement limiting mechanism, a drive shaft, a plunger, a cylinder, a flow distribution plate, an inclined The variable head is equipped with a proportional electromagnet, a two-position three-way electromagnetic reversing valve and a pressure regulating mechanism, and an internal processing oil circuit is provided for the demand of internal parts for oil. The proportional electromagnet is installed in the two Under the same side of the three-way electromagnetic reversing valve, the adjusting mechanism is located at the same horizontal position of the proportional electromagnet; The proportional electromagnet is placed in the variable head hole, with internal threads processed in the hole, and the position of the proportional electromagnet is fixed with a plug; as an electro-mechanical conversion element, the obtained electrical signal is converted into a force signal, and its output force is related to the adjustment mechanism. Hydraulic pressure comparison, control the size of the spool orifice, adjust the flow into the variable cylinder, adjust the inclination of the swash plate, and thus adjust the output pressure of the variable pump; The two-position three-way electromagnetic reversing valve is installed in the hole processed by the variable head. The bottom of the hole is machined with internal threads. The position of the two-position three-way electromagnetic reversing valve is fixed with a plug. Connect the oil outlet of the variable pump, the oil chamber of the spring base of the pressure regulating mechanism and the regulating chamber of the variable pump; among them, when the electromagnet of the two-position three-way electromagnetic reversing valve is energized, it pushes its spool to move, connecting the oil outlet of the variable pump and the adjusting chamber of the variable pump. Press the spring base oil chamber of the mechanism, continue to compress the spring until it reaches the limit device, and realize the two-stage pressure adjustment of the variable pump. On this basis, the proportional electromagnet is energized to realize the continuous pressure adjustment. Electric, variable pump work in low pressure state, two-stage pressure and continuous pressure regulation are invalid; The pressure regulating mechanism includes a pressure regulating spring, a spring base, a limit mechanism, a regulating valve core, and the regulating valve core is connected with the push rod of the proportional electromagnet, and the proportional electromagnet converts the current signal obtained through the proportional amplifier board into an output force; The mechanism is installed in the variable head, and the bottom is machined with internal threads. The pre-tightening force of the pressure regulating spring is adjusted through the plug. It moves under the combined action of the spring force, the output force of the proportional electromagnet and the hydraulic pressure, and communicates the pressure chamber of the follower piston with the return. The oil phase connection or the communication follower piston is connected with the high pressure oil chamber, so that the inclination angle of the oil pump swash plate increases or decreases, and then the output flow rate of the electro-hydraulic proportional axial piston variable pump increases or decreases; the pressure regulating mechanism Determines the outlet pressure of the electro-hydraulic proportional axial piston variable pump, the low pressure value of the pressure regulating mechanism is set by adjusting the preload of the pressure regulating spring, and the high pressure value is set by the pressure regulating spring and the system hydraulic pressure; In the mounting hole of the pressure regulating mechanism, a boss is processed to limit the stroke of the spring seat of the pressure regulating mechanism and prevent the failure of the spring from excessive compression, thereby realizing two-stage compression of the spring. 2. the continuously regulated electro-hydraulic proportional axial plunger variable pump for aircraft hydraulic system according to claim 1, is characterized in that: in the plunger pump, nine plungers are evenly placed on the continuously regulated electro-hydraulic ratio Inside the axial piston variable pump cylinder, it is connected with the drive shaft through splines, and the valve plate is fixed on the cylinder body of the continuous pressure-adjustable hydraulic proportional axial piston variable pump, and the continuous pressure-adjustable hydraulic pressure is driven by the external input torque. The cylinder body of the proportional axial piston variable pump rotates, and the piston reciprocates linearly under the restriction of the return mechanism, so as to realize the pressure output of the oil pump; when the piston moves in the direction away from the cylinder body, the oil is sucked from the oil suction port through the valve plate. When the plunger moves in the direction of the cylinder block, the high-pressure oil is transported from the oil outlet to the hydraulic pipeline through the distribution plate. 3. the continuously regulated electro-hydraulic proportional axial piston variable pump for aircraft hydraulic system according to claim 1, is characterized in that: two-position three-way electromagnetic reversing valve electromagnet is energized, so that it works in two stages In the pressure regulation state, the proportional electromagnet is energized, and the thrust corresponding to the current size is generated, so that the sum of the electromagnet thrust and the force of the oil pump outlet pressure acting on the valve core is equal to the spring force, so with the change of the proportional electromagnet input voltage , the outlet pressure of the oil pump changes accordingly. 4. the continuously regulated pressure-hydraulic proportional axial piston variable pump for aircraft hydraulic system according to claim 3, is characterized in that: because the outlet pressure of the oil pump is equal to the spring force minus the electromagnet thrust, along with the proportional valve thrust That is, as the input voltage increases, the pressure of the oil pump gradually decreases; the outlet pressure of the oil pump changes continuously between the maximum output pressure and the minimum output pressure. 5. The continuously regulating pressure-hydraulic proportional axial plunger variable pump for aircraft hydraulic system according to claim 1, is characterized in that: when the proportional electromagnet fails and cannot output continuously variable suction, the continuous pressure regulating The outlet pressure of the hydraulic proportional axial piston variable pump acts on the pressure regulating mechanism, which is compared with the spring force. Therefore, two-stage compression of the spring can be realized by switching the two-position three-way solenoid valve, and the pressure changes in two stages. With the continuous pressure regulation The outlet pressure of the electro-hydraulic proportional axial piston variable pump can be adjusted in two stages. 6. The continuously regulated electro-hydraulic proportional axial plunger variable pump for aircraft hydraulic system according to claim 1, is characterized in that: the two-position three-way electromagnetic reversing valve electromagnet is de-energized, and the system just works at the lowest In the working state of pressure, the two-stage pressure regulation function can be realized when the power is turned on.

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