CN117184393A - Electrohydraulic steering device and method with power failure emergency function - Google Patents

Abstract

The application discloses an electrohydraulic steering device with a power-failure emergency function and a method thereof, wherein the electrohydraulic steering device comprises: the hydraulic control device comprises a hydraulic power source, an electromagnetic reversing valve, an electromagnetic ball valve, a hydraulic control one-way valve, an energy accumulator, an oil tank and a hydraulic cylinder; the hydraulic power source comprises a motor and a bidirectional hydraulic pump, the motor is connected with the bidirectional hydraulic pump, and the motor is used for driving the bidirectional hydraulic pump; the electromagnetic reversing valve is used for switching between an oil supply loop of the hydraulic cylinder and an oil charging loop of the energy accumulator, the electromagnetic ball valve is arranged between the energy accumulator and the hydraulic control one-way valve, the energy accumulator is used as a standby energy source for power failure emergency steering, the influence of the conditions of power failure, cable burning and the like is avoided, and the hydraulic control one-way valve has strong environmental adaptability.

Description

Electrohydraulic steering device and method with power failure emergency function

Technical Field

The application relates to the technical field of electromechanical control, in particular to an electrohydraulic steering device with a power failure emergency function and a method thereof.

Background

In the prior art, the steering gear of the marine steering engine mainly comprises two types, namely a traditional concentrated oil source and a high-power servo device controlled by a servo valve, and a novel electrohydraulic steering device.

The electrohydraulic steering servo device has certain advantages in practical application due to the advantages of integration, miniaturization, easy installation and maintenance and the like, and is also paid attention to the industry in recent years.

For safety, the marine steering device needs to consider the design of emergency steering conditions, and in the prior art, mostly adopts dual redundancy configuration to improve the safety and reliability of steering. However, the method still has the defect under certain specific conditions, and cannot cope with the emergency floating working condition under the condition of power failure of the whole ship.

Disclosure of Invention

Aiming at the defects or improvement demands of the prior art, the application provides the electrohydraulic steering device with the power-failure emergency function and the electrohydraulic steering method, which can be used for unmanned aircrafts to carry out emergency floating operation under the conditions of power failure, cable burnout and the like, namely the steering engine steering device turns to a floating rudder angle after power failure so as to avoid unnecessary loss caused by rapid sinking of the aircrafts.

In order to achieve the above purpose, the present application adopts the following technical scheme.

Some embodiments of the present application provide an electrohydraulic steering device with a power loss emergency function, including: the hydraulic control device comprises a hydraulic power source, an electromagnetic reversing valve, an electromagnetic ball valve, a hydraulic control one-way valve, an energy accumulator, an oil tank and a hydraulic cylinder;

the hydraulic power source comprises a motor and a bidirectional hydraulic pump, the bidirectional hydraulic pump comprises a first pump port and a second pump port, the hydraulic cylinder comprises a first cylinder port and a second cylinder port, the first pump port of the bidirectional hydraulic pump is connected with the first cylinder port of the hydraulic cylinder, the second pump port of the bidirectional hydraulic pump is connected with the second cylinder port of the hydraulic cylinder, the motor is connected with the bidirectional hydraulic pump, and the motor is used for driving the bidirectional hydraulic pump; the second cylinder port of the hydraulic cylinder is connected with the oil tank;

the electromagnetic reversing valve is arranged between the first pump port of the bidirectional hydraulic pump and the first cylinder port of the hydraulic cylinder, the electromagnetic reversing valve is also connected with the energy accumulator, and the energy accumulator is connected with the first cylinder port and the second cylinder port of the hydraulic cylinder through the electromagnetic ball valve and the hydraulic control one-way valve;

the electromagnetic reversing valve is used for switching between an oil supply loop of the hydraulic cylinder and an oil charge loop of the energy accumulator, switching to the oil charge loop of the energy accumulator to charge the energy accumulator when the electromagnetic reversing valve is powered on, switching to the oil supply loop of the hydraulic cylinder when the electromagnetic reversing valve is powered off, and supplying oil to a first cylinder port of the hydraulic cylinder through a first pump port of the bidirectional hydraulic pump;

the hydraulic control one-way valve comprises a first hydraulic control one-way valve and a second hydraulic control one-way valve, the first hydraulic control one-way valve is arranged between the energy accumulator and the hydraulic cylinder, and the second hydraulic control one-way valve is arranged between the oil tanks of the hydraulic cylinder;

the electromagnetic ball valve is arranged between the energy accumulator and the hydraulic control one-way valve, the electromagnetic ball valve is in a communication state in a power failure state, pressure oil reaches the hydraulic control one-way valve through the electromagnetic ball valve, the hydraulic control one-way valve is conducted, the pressure oil of the energy accumulator enters a first cylinder port of the hydraulic cylinder through the first hydraulic control one-way valve so as to conduct emergency steering, and hydraulic oil at a second cylinder port of the hydraulic cylinder returns to an oil tank through the second hydraulic control one-way valve; the electromagnetic ball valve is in a closed state in a power-on state, and the hydraulic control one-way valve disconnects the energy accumulator from the hydraulic cylinder.

In some embodiments, the electrohydraulic steering device further comprises a first pressure sensor and a control unit, wherein the first pressure sensor is connected with the control unit and the energy accumulator, the first pressure sensor is used for detecting the pressure of the energy accumulator, the controller is further connected with the electromagnetic directional valve and used for controlling the electromagnetic directional valve to be electrified when the pressure of the energy accumulator is smaller than a set value, and starting the bidirectional hydraulic pump to charge the energy accumulator until the pressure of the energy accumulator reaches the set value and controlling the electromagnetic directional valve to be powered off.

In some embodiments, the fuel tank comprises a first fuel tank connected to the bi-directional hydraulic pump and a second fuel tank connected to the accumulator; the hydraulic pump is characterized in that a first check valve is arranged between the first oil tank and a first pump port of the bidirectional hydraulic pump, a second check valve is arranged between the first oil tank and a second pump port of the bidirectional hydraulic pump, and the conduction directions of the first check valve and the second check valve are the directions from the first oil tank to the bidirectional hydraulic pump.

In some embodiments, the electro-hydraulic steering device includes a third check valve disposed between the accumulator and the electromagnetic directional valve, wherein a direction of conduction of the third check valve is a direction in which the electromagnetic directional valve flows to the accumulator.

In some embodiments, the electro-hydraulic steering device includes a balance valve disposed between the bi-directional hydraulic pump and the hydraulic cylinder, and further includes a first relief valve and a second relief valve disposed between the balance valve and the first tank.

In some embodiments, the electro-hydraulic steering device includes a third relief valve disposed between the accumulator and the second tank.

In some embodiments, the electrohydraulic steering device comprises a solenoid valve, the solenoid valve is arranged between the energy accumulator and the second oil tank, and when the solenoid valve is powered on, the solenoid valve conducts the energy accumulator and the second oil tank, so that hydraulic oil of the energy accumulator flows back to the second oil tank completely, and the rudder angle is reset to zero.

In some embodiments, the motor is a servo motor, and the servo motor controls the driving direction and the flow of the bidirectional hydraulic pump through forward and reverse rotation and rotation speed control.

In some embodiments, the accumulator is a diaphragm accumulator.

The application also provides an electrohydraulic steering method, which is performed by adopting the electrohydraulic steering device with the power-loss emergency function in any embodiment, and the electrohydraulic steering method further comprises the following steps:

starting the bidirectional hydraulic pump to charge the accumulator with oil, and switching a circuit of the bidirectional hydraulic pump to a normal steering circuit when the pressure of the accumulator reaches a set value;

under the power failure state, the bidirectional hydraulic pump stops rotating, an emergency function is started, the electromagnetic ball valve is communicated, pressure oil of the energy accumulator enters a first cylinder port of the hydraulic cylinder through the first hydraulic control one-way valve to push a rudder, the rudder angle is pushed to be full of the rudder angle from any position, and the state is kept unchanged;

and under the condition that the electromagnetic valve is electrified, the electromagnetic valve conducts the energy accumulator and the second oil tank, hydraulic oil of the energy accumulator flows back to the second oil tank of the oil tank completely, and the rudder angle is zeroed.

Compared with the prior art, the application adopts the energy accumulator as a standby energy source to perform power failure emergency steering, is not influenced by the conditions of power failure, cable burnout and the like, and has stronger environmental adaptability. On the other hand, the application has simple principle, adopts modularized design, is simple to manufacture, has high reliability and maintainability, can rapidly rotate any rudder angle to an upper full rudder angle in a power failure state, can realize the floating of the aircraft in an emergency state, and has stronger practicability and popularization value. In some embodiments of the application, under the condition of no control signal, even if a certain external load exists, the original rudder angle can be kept basically unchanged, and the control precision of the rudder angle is higher; and simultaneously, after exceeding a certain load, the two cavities of the hydraulic cylinder bypass to the oil tank to unload so as to ensure the safety of steering.

Drawings

Fig. 1 is a schematic hydraulic schematic diagram of an electrohydraulic steering device with a power loss emergency function according to some embodiments of the present application.

Fig. 2 is a schematic structural block diagram of an electrohydraulic steering device with a power loss emergency function according to some embodiments of the present application.

Fig. 3 is a schematic three-dimensional structure of an electro-hydraulic steering apparatus according to some embodiments of the present application.

Fig. 4 is a schematic plan view of an electro-hydraulic steering apparatus according to some embodiments of the present application.

Fig. 5 is a schematic partial cross-sectional view of an electro-hydraulic steering apparatus according to some embodiments of the present application.

Fig. 6 is a schematic block diagram of an electrohydraulic steering device with a power loss emergency function according to some embodiments of the present application.

Detailed Description

The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

In the description of the present application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "circumferential", etc. indicate orientations or positional relationships based on the one shown in the drawings, are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. The interpretation of such words should be done from the perspective of one skilled in the art. For example, "above … …", "below … …" should be understood as the positional relationship of the body structure or structure of the component or the like in the initial state, which may be broken through during movement. "… … disposed on … …" is to be understood as the general connection of the components, not necessarily above.

In the present application, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," "secured," and the like are to be construed broadly in view of those skilled in the art and may, for example, be fixedly connected, detachably connected, or be integrated; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Referring to fig. 1-5, some embodiments of the present application provide an electrohydraulic steering device with a power loss emergency function, including: the hydraulic power source 100, the electromagnetic reversing valve 3, the electromagnetic ball valve 4, the hydraulic control one-way valve, the energy accumulator 6, the oil tank and the hydraulic cylinder 200.

The hydraulic power source 100 comprises a motor 1 and a bidirectional hydraulic pump 2, the bidirectional hydraulic pump 2 comprises a first pump port P1 and a second pump port P2, the hydraulic cylinder 200 comprises a first cylinder port A and a second cylinder port B, the first pump port P1 of the bidirectional hydraulic pump 2 is connected with the first cylinder port A of the hydraulic cylinder 200, the second pump port P2 of the bidirectional hydraulic pump is connected with the second cylinder port B of the hydraulic cylinder, the motor 1 is connected with the bidirectional hydraulic pump 2, and the motor is used for driving the bidirectional hydraulic pump; and a second cylinder port of the hydraulic cylinder is connected with the oil tank.

The electromagnetic directional valve 3 is arranged between the first pump port of the bidirectional hydraulic pump and the first cylinder port of the hydraulic cylinder, the electromagnetic directional valve 3 is also connected with the energy accumulator 6, and the energy accumulator 6 is connected with the first cylinder port and the second cylinder port of the hydraulic cylinder 200 through the electromagnetic ball valve 4 and the hydraulic control one-way valve.

The electromagnetic directional valve 3 is used for switching between an oil supply loop of the hydraulic cylinder and an oil charge loop of the energy accumulator, switching to the oil charge loop of the energy accumulator to charge the energy accumulator when the electromagnetic directional valve is powered on, switching to the oil supply loop of the hydraulic cylinder when the electromagnetic directional valve is powered off, and supplying oil to the first cylinder port of the hydraulic cylinder through the first pump port of the bidirectional hydraulic pump.

The hydraulic check valve comprises a first hydraulic check valve 91 and a second hydraulic check valve 92, the first hydraulic check valve 91 is arranged between the accumulator 6 and the hydraulic cylinder 200, and the second hydraulic check valve 92 is arranged between the hydraulic cylinder 200 and the oil tank.

The electromagnetic ball valve 4 is arranged between the energy accumulator and the hydraulic control one-way valve, the electromagnetic ball valve 4 is in a communication state in a power failure state, pressure oil reaches the hydraulic control one-way valve through the electromagnetic ball valve 4, the hydraulic control one-way valve is conducted, the pressure oil of the energy accumulator enters a first cylinder port A of the hydraulic cylinder through the first hydraulic control one-way valve 91 to perform emergency steering, and hydraulic oil of a second cylinder port B of the hydraulic cylinder returns to an oil tank through the second hydraulic control one-way valve 92; the electromagnetic ball valve 4 is in a closed state in the power-on state, and the hydraulic control one-way valve disconnects the accumulator 6 from the hydraulic cylinder 200.

In the embodiment of the present application, the hydraulic power source 100 is a power source module assembly for normal steering, and the accumulator 6 is a power source module assembly for emergency steering. In some embodiments, the motor is a servo motor. In some embodiments, the accumulator is a diaphragm accumulator. The servo motor controls the driving direction and flow of the bidirectional hydraulic pump through forward and reverse rotation and rotation speed control. The servo motor is connected with the bidirectional hydraulic pump through a coupling to form a hydraulic power source together, and the control of the driving direction and the system flow is realized by controlling the forward rotation and the reverse rotation of the servo motor and the rotation speed control. The control unit adopts a PLC control mode, and simultaneously has the functions of receiving the instruction from the console through two paths of communication channels of Ethernet and serial ports and sending a control instruction to the servo motor by using a control algorithm. The electromagnetic directional valve is used for switching the first cylinder port of the hydraulic cylinder, the oil supply loop and the accumulator oil filling loop, when the electromagnetic directional valve is powered on, the loop is switched to the diaphragm accumulator oil filling loop, the accumulator is filled with oil, steering can not be performed temporarily, and when the electromagnetic directional valve is powered off, the loop is switched to the oil supply loop of the first cylinder port of the hydraulic cylinder, and steering can be performed normally. The electromagnetic ball valve is in a communication state in a power failure state, pressure oil reaches the hydraulic control one-way valve through the electromagnetic ball valve, the hydraulic control one-way valve is conducted at the moment, the pressure oil of the energy accumulator can enter the first cylinder opening of the hydraulic cylinder through the hydraulic control one-way valve to push the hydraulic cylinder to rotate for emergency steering, and hydraulic oil in the second cylinder opening of the hydraulic cylinder can return to the oil tank through the hydraulic control one-way valve. The electromagnetic ball valve is in a closed state in the power-on state, and separates the energy accumulator from the hydraulic cylinder, so that steering can be performed normally.

In some embodiments, the electrohydraulic steering device further includes a first pressure sensor 51 and a control unit, the first pressure sensor 51 is connected to the control unit and the accumulator 6, the first pressure sensor 51 is used for detecting the pressure of the accumulator 6, the controller is further connected to the electromagnetic directional valve 3, and is used for controlling the electromagnetic directional valve 3 to be powered when the pressure of the accumulator 6 is smaller than a set value, starting the bidirectional hydraulic pump 2 to charge the accumulator 6 until the pressure of the accumulator 6 reaches the set value, and controlling the electromagnetic directional valve 3 to be powered off. The accumulator 6 is a diaphragm accumulator, the inside of which is filled with inert gas with a certain pressure so as to keep the inside of the accumulator at a certain pressure, and a pressure sensor is arranged at the outlet of the accumulator for detecting the oil pressure in the diaphragm accumulator.

In some embodiments, the oil tanks include a first oil tank 101 and a second oil tank 102, the first oil tank 101 being connected to the bi-directional hydraulic pump 2, the second oil tank 102 being connected to the accumulator 6. A first check valve 81 is disposed between the first oil tank 101 and the first pump port P1 of the bidirectional hydraulic pump, a second check valve 82 is disposed between the first oil tank 101 and the second pump port P2 of the bidirectional hydraulic pump, and the conducting directions of the first check valve 81 and the second check valve 82 are all directions from the first oil tank 101 to the bidirectional hydraulic pump 2. In some embodiments, the first tank is a pressurized tank, with some pre-compression. Under the condition of no control signal, even if a certain external load exists, the original rudder angle can be kept basically unchanged, and the control precision of the rudder angle is higher; and simultaneously, after exceeding a certain load, two cavities (two cavities respectively communicated with the first cylinder port A and the second cylinder port B) of the hydraulic cylinder bypass to the oil tank to unload so as to ensure the steering safety. In some embodiments, the first and second cylinder ports a, B of the hydraulic cylinder are provided with pressure sensors and pressure test points, in particular, the first cylinder port a of the hydraulic cylinder is provided with a second pressure sensor 52 and the second cylinder port B is provided with a third pressure sensor 53.

In some embodiments, the electrohydraulic steering device includes a third check valve 83, the third check valve 83 is disposed between the accumulator 6 and the electromagnetic directional valve 3, and the conducting direction of the third check valve 83 is that the electromagnetic directional valve 3 flows to the accumulator 6.

In some embodiments, the electro-hydraulic steering device includes a balance valve 11, the balance valve 11 being disposed between the two-way hydraulic pump 2 and the hydraulic cylinder 200, and a first relief valve 71 and a second relief valve 72, the first relief valve 71 and the second relief valve 72 being disposed between the balance valve 11 and the first tank 101. In some embodiments, the balancing valve may be replaced with a pilot operated check valve having a similar function.

In some embodiments, an electromagnetic valve and a safety valve are connected in parallel at the outlet of the energy accumulator, and a one-way valve is arranged between the safety valve and the electromagnetic reversing valve. In some embodiments, the electrohydraulic steering device includes a third relief valve 73, and the relief valve at the accumulator outlet is the third relief valve 73. The third relief valve 73 is arranged between the accumulator 6 and the second tank 102.

In some embodiments, the electrohydraulic steering device includes a solenoid valve 12, the solenoid valve 12 is disposed between the accumulator 6 and the second tank 102, and the solenoid valve 12 is configured to, when the rudder angle is zero, open the accumulator 6 and the second tank 102, so that hydraulic oil of the accumulator 6 flows back to the second tank 102. When the rudder angle is required to return to zero, the electromagnetic valve 12 is powered on, the hydraulic oil of the accumulator flows back to the oil tank 102 completely, and all power sources are disconnected.

The application also provides an electrohydraulic steering method, which is performed by adopting the electrohydraulic steering device with the power-loss emergency function in any embodiment, and the electrohydraulic steering method further comprises the following steps:

starting the bidirectional hydraulic pump to charge the accumulator with oil, and switching a circuit of the bidirectional hydraulic pump to a normal steering circuit when the pressure of the accumulator reaches a set value;

under the power failure state, the bidirectional hydraulic pump stops rotating, an emergency function is started, the electromagnetic ball valve is communicated, pressure oil of the energy accumulator enters a first cylinder port of the hydraulic cylinder through the first hydraulic control one-way valve to push a rudder, the rudder angle is pushed to be full of the rudder angle from any position, and the state is kept unchanged;

and under the condition that the electromagnetic valve is electrified, the electromagnetic valve conducts the energy accumulator and the second oil tank, hydraulic oil of the energy accumulator flows back to the second oil tank of the oil tank completely, and the rudder angle is zeroed.

Compared with the prior art, the application adopts the energy accumulator as a standby energy source to perform power-failure emergency steering, is not influenced by the conditions of communication interruption, fire and the like, and has stronger environmental adaptability. On the other hand, the application has simple principle, adopts modularized design, is simple to manufacture, has high reliability and maintainability, can rapidly rotate any rudder angle to an upper full rudder angle in a power failure state, can realize the floating of the aircraft in an emergency state, and has stronger practicability and popularization value.

Specifically, in the embodiment of the present application, referring to fig. 2 and 6, the electro-hydraulic steering apparatus having the power loss emergency function includes a power source module 1000 for normal steering, a power source module 2000 for emergency steering, a power source switching module 3000, a normal steering circuit 4000, and a control unit 5000. The normal steering power source module 1000 includes a motor 1 and a bidirectional hydraulic pump 2, and the normal steering circuit 4000 includes a circuit including a balance valve 11, a first relief valve 71, a second relief valve 72, and the like. The power source module 2000 for emergency steering includes an accumulator 6 and the like. The power source switching module 3000 includes an electromagnetic ball valve 4, a first pilot operated check valve 91, a second pilot operated check valve 92, and the like. The control unit 5000 is connected to the power source module 1000 and the power source switching module 3000 for normal steering. The constituent elements of each module of the electro-hydraulic steering apparatus may be combined with each technical feature of any of the above embodiments to have the same function.

Referring to fig. 3 to 5, in some embodiments of the present application, a first oil tank 101 and a second oil tank 102 are disposed in parallel, a motor 1 is disposed at one end of the first oil tank 101, a solenoid directional valve 3 and a solenoid ball valve 4 are disposed at one end of the second oil tank 102, a bi-directional hydraulic pump 2 is disposed in the first oil tank 101, and a first relief valve 71 and a second relief valve 72 are disposed at the top of the first oil tank 101. The second pressure sensor 52 and the third pressure sensor 53 are disposed on one side of the second tank 102, and the third relief valve 73, the accumulator 6, and the solenoid valve 12 are disposed on the other side of the second tank 102. The electromagnetic directional valve 3, the electromagnetic ball valve 4 and the motor 1 are arranged on the same side of the first oil tank 101 and the second oil tank 102. The first pilot operated check valve 91 and the second pilot operated check valve 92 are provided on both sides of the second tank 102, respectively. The balance valve 11 includes a first balance valve 111 and a second balance valve 112, and the first balance valve 111 and the second balance valve 112 are provided on both sides of the first tank 101, respectively. In the embodiment of the application, the structure is compact, the space is fully utilized, the modularized design is adopted, the structure is simple, the manufacture is simple, and the reliability and the maintainability are very high.

In some embodiments of the present application, the first tank 101 is a pressurized tank, and has a certain pre-pressure. Under the condition of no control signal, even if a certain external load exists, the original rudder angle can be kept basically unchanged, and the control precision of the rudder angle is higher; and simultaneously, after exceeding a certain load, the two cavities of the hydraulic cylinder bypass to the oil tank to unload so as to ensure the safety of steering.

It will be appreciated that the various features of the embodiments described above may be combined in any desired manner, and that for brevity, all of the possible combinations of features of the embodiments described above may not be described. It should be understood that the scope of the present description should be considered as long as there is no contradiction between the combinations of these technical features.

It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the application and is not intended to limit the application, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the application are intended to be included within the scope of the application.

Claims (10)

1. An electrohydraulic steering device having a power loss emergency function, comprising: the hydraulic control device comprises a hydraulic power source, an electromagnetic reversing valve, an electromagnetic ball valve, a hydraulic control one-way valve, an energy accumulator, an oil tank and a hydraulic cylinder;

the hydraulic power source comprises a motor and a bidirectional hydraulic pump, the bidirectional hydraulic pump comprises a first pump port and a second pump port, the hydraulic cylinder comprises a first cylinder port and a second cylinder port, the first pump port of the bidirectional hydraulic pump is connected with the first cylinder port of the hydraulic cylinder, the second pump port of the bidirectional hydraulic pump is connected with the second cylinder port of the hydraulic cylinder, the motor is connected with the bidirectional hydraulic pump, and the motor is used for driving the bidirectional hydraulic pump; the second cylinder port of the hydraulic cylinder is connected with the oil tank;

the electromagnetic reversing valve is arranged between the first pump port of the bidirectional hydraulic pump and the first cylinder port of the hydraulic cylinder, the electromagnetic reversing valve is also connected with the energy accumulator, and the energy accumulator is connected with the first cylinder port and the second cylinder port of the hydraulic cylinder through the electromagnetic ball valve and the hydraulic control one-way valve;

the electromagnetic reversing valve is used for switching between an oil supply loop of the hydraulic cylinder and an oil charge loop of the energy accumulator, switching to the oil charge loop of the energy accumulator to charge the energy accumulator when the electromagnetic reversing valve is powered on, switching to the oil supply loop of the hydraulic cylinder when the electromagnetic reversing valve is powered off, and supplying oil to a first cylinder port of the hydraulic cylinder through a first pump port of the bidirectional hydraulic pump;

the hydraulic control one-way valve comprises a first hydraulic control one-way valve and a second hydraulic control one-way valve, the first hydraulic control one-way valve is arranged between the energy accumulator and the hydraulic cylinder, and the second hydraulic control one-way valve is arranged between the oil tanks of the hydraulic cylinder;

the electromagnetic ball valve is arranged between the energy accumulator and the hydraulic control one-way valve, the electromagnetic ball valve is in a communication state in a power failure state, pressure oil reaches the hydraulic control one-way valve through the electromagnetic ball valve, the hydraulic control one-way valve is conducted, the pressure oil of the energy accumulator enters a first cylinder port of the hydraulic cylinder through the first hydraulic control one-way valve so as to conduct emergency steering, and hydraulic oil at a second cylinder port of the hydraulic cylinder returns to an oil tank through the second hydraulic control one-way valve; the electromagnetic ball valve is in a closed state in a power-on state, and the hydraulic control one-way valve disconnects the energy accumulator from the hydraulic cylinder.

2. The electro-hydraulic steering device of claim 1, further comprising a first pressure sensor and a control unit, wherein the first pressure sensor is connected with the control unit and the accumulator, the first pressure sensor is used for detecting the pressure of the accumulator, and the controller is further connected with the electromagnetic directional valve and is used for controlling the electromagnetic directional valve to be powered on when the pressure of the accumulator is smaller than a set value, starting the bidirectional hydraulic pump to charge the accumulator until the pressure of the accumulator reaches the set value, and controlling the electromagnetic directional valve to be powered off.

3. The electro-hydraulic steering apparatus of claim 2, wherein the fuel tank includes a first fuel tank and a second fuel tank, the first fuel tank being connected to the bi-directional hydraulic pump, the second fuel tank being connected to the accumulator; the hydraulic pump is characterized in that a first check valve is arranged between the first oil tank and a first pump port of the bidirectional hydraulic pump, a second check valve is arranged between the first oil tank and a second pump port of the bidirectional hydraulic pump, and the conduction directions of the first check valve and the second check valve are the directions from the first oil tank to the bidirectional hydraulic pump.

4. The electro-hydraulic steering apparatus according to claim 3, wherein the electro-hydraulic steering apparatus includes a third check valve provided between the accumulator and the electromagnetic directional valve, and a conduction direction of the third check valve is a direction in which the electromagnetic directional valve flows to the accumulator.

5. The electro-hydraulic steering apparatus of claim 4, wherein the electro-hydraulic steering apparatus includes a balance valve disposed between the two-way hydraulic pump and the hydraulic cylinder, and further comprising a first relief valve and a second relief valve disposed between the balance valve and the first tank.

6. The electro-hydraulic steering apparatus of claim 5, wherein the electro-hydraulic steering apparatus includes a third relief valve disposed between the accumulator and the second tank.

7. The electro-hydraulic steering apparatus according to claim 6, wherein the electro-hydraulic steering apparatus includes a solenoid valve that is provided between the accumulator and the second tank, the solenoid valve, when energized, turns on the accumulator and the second tank so that hydraulic oil of the accumulator flows all the way back into the second tank.

8. The electro-hydraulic steering apparatus according to any one of claims 1 to 7, wherein the motor is a servo motor that controls a driving direction and a flow rate of the bidirectional hydraulic pump by forward and reverse rotation and rotational speed control.

9. The electro-hydraulic steering apparatus of any one of claims 1-7, wherein the accumulator is a diaphragm accumulator.

10. An electro-hydraulic steering method, wherein the electro-hydraulic steering method is performed by using the electro-hydraulic steering device with a power-loss emergency function according to claim 7, the electro-hydraulic steering method further comprising:

starting the bidirectional hydraulic pump to charge the accumulator with oil, and switching a circuit of the bidirectional hydraulic pump to a normal steering circuit when the pressure of the accumulator reaches a set value;

under the power failure state, the bidirectional hydraulic pump stops rotating, an emergency function is started, the electromagnetic ball valve is communicated, pressure oil of the energy accumulator enters a first cylinder port of the hydraulic cylinder through the first hydraulic control one-way valve to push a rudder, the rudder angle is pushed to be full of the rudder angle from any position, and the state is kept unchanged;

and under the condition that the electromagnetic valve is electrified, the electromagnetic valve conducts the energy accumulator and the second oil tank, hydraulic oil of the energy accumulator flows back to the second oil tank of the oil tank completely, and the rudder angle is zeroed.