CN109131547B - An integrated electro-hydraulic steering actuation unit and control method - Google Patents

Abstract

An integrated electro-hydraulic steering actuating unit and a control method. Externally inputted control signals control the rotation direction and speed of a bidirectional servo motor, and the bidirectional servo motor drives the extension direction and extension speed of an execution oil cylinder. The control valve block assembly is used to maintain the movement position of the oil cylinder when the two-way servo motor stops working, and can be used to perform the extension action of the oil cylinder. ;The control valve block assembly can limit the working pressure of the execution cylinder when the temperature of the execution cylinder or the load changes suddenly, and is used to set the maximum working pressure of the two-way gear pump, limit the output power of the two-way gear pump, and prevent the overload of the two-way servo motor; Control valve block The assembly can realize the connection between the two chambers of the execution cylinder and is in a floating working state, which improves the safety of the integrated electro-hydraulic steering actuating unit for steering work under emergency conditions.

Description

An integrated electro-hydraulic steering actuation unit and control method

technical field

The invention relates to an integrated electro-hydraulic steering actuating unit and a control method, belonging to the technical field of hydraulic transmission and control.

Background technique

At present, the new generation of intelligent special vehicles adopts all-electric drive, the steering system has full steering function, and can realize various steering modes and fault monitoring functions to meet the steering requirements under various complex working conditions. The system structure is huge and complex, and the steering mode is single. It cannot realize the switching of multi-steering modes according to the use requirements, and the electric drive mode cannot be adopted, which can no longer meet the steering needs of a new generation of intelligent special vehicles.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide an integrated electro-hydraulic steering actuating unit and a control method, adopting an electric drive mode, the left and right wheels of each axle are independently driven by a single electro-hydraulic actuating unit, Realize the all-wheel independent drive steering of intelligent special vehicles, and solve the problem of multi-mode steering; at the same time, simplify the complex steering system into the module construction of "new electro-hydraulic integrated steering actuation unit" to realize the steering function of any shaft system of intelligent special vehicles Modular and fast design.

The technical solution solved by the present invention is: an integrated electro-hydraulic steering actuating unit, comprising: a bidirectional servo motor, a bidirectional gear pump, an execution oil cylinder (preferably a double-rod hydraulic cylinder), a transmission shaft, a closed oil tank, and a control valve block assembly;

The external input control signal controls the rotation and speed of the bidirectional servo motor. The bidirectional servo motor drives the bidirectional gear pump to output the oil flow through the transmission shaft, thereby driving the extension direction and extension speed of the execution cylinder (double-rod hydraulic cylinder).

The control valve block assembly is used to maintain the movement position of the oil cylinder when the two-way servo motor stops working, and can be used to carry out the extension and retraction of the oil cylinder. The oil on the return side returns to the closed tank for heat dissipation and reduces the temperature of the oil ;The control valve block assembly can limit the working pressure of the execution cylinder when the temperature of the execution cylinder increases or the load suddenly changes, and is used to set the maximum working pressure of the bidirectional gear pump, limit the output power of the bidirectional gear pump, and prevent the bidirectional servo motor from overloading; control The valve block assembly can realize the connection between the two chambers of the execution oil cylinder in a floating working state and improve the reliability of the work.

Control valve block assembly, including: valve body, check valve, relief valve, hydraulic control check valve, electromagnetic reversing valve;

Check valve, relief valve, hydraulic control check valve, electromagnetic reversing valve are installed in the valve body;

The two oil ports of the bidirectional gear pump are provided with overflow valves, which are used to set the maximum working pressure of the oil source, limit the output power of the bidirectional gear pump, and prevent the bidirectional servo motor from overloading;

The two oil ports of the execution cylinder are provided with relief valves, which can limit the working pressure of the execution cylinder when the temperature of the execution cylinder increases or the load suddenly changes;

One-way valves are respectively set from the closed oil tank to the two oil ports of the two-way gear pump to realize the normal switching of the one-way pressure build-up and oil suction functions of the two-way gear pump.

The two chambers of the execution cylinder are respectively provided with hydraulic control check valves, which are used to return the oil on the return side to the closed tank to dissipate heat and reduce the temperature of the circulating working oil when the cylinder is extended and retracted.

An electromagnetic reversing valve is set between the two chambers of the execution cylinder. When the power is not available, the two working chambers of the execution cylinder are disconnected; when the power is turned on, the two working chambers of the execution cylinder are connected for emergency conditions , to achieve the two-chamber communication of the execution cylinder in a floating working state.

The floating working state is: when the electromagnetic reversing valve in the control valve block assembly is energized, the execution oil cylinder can follow the movement under the load.

Emergency conditions, including: bidirectional servo motor failure or bidirectional gear pump failure.

The electric energy output by the bidirectional servo motor is converted into the pressure energy of the oil source through the bidirectional gear pump, and the extension and retraction of the oil cylinder is controlled by the oil source.

The actuator cylinder adopts a double-rod hydraulic cylinder, which includes two oil chambers. One-way movement of the piston rod in the double-rod hydraulic cylinder is realized by feeding oil into one chamber and returning oil to the other chamber.

Double-rod hydraulic cylinder, including: cylinder barrel, piston rod, end cover, support lug, base;

The cylinder barrel and the base are fixedly connected, and the piston rod passes through the cylinder barrel and the end caps at both ends of the cylinder barrel; the piston rod divides the cylinder barrel into two parts, and the stroke is two oil chambers. The lugs are arranged at both ends of the piston rod to connect with the external load .

The closed oil tank is a closed hydraulic oil tank, which adopts a closed structure to ensure that the two-way gear pump has a good oil absorption capacity under any working posture of the integrated electro-hydraulic steering actuation unit.

The power unit and the actuator cylinder composed of the bidirectional servo motor, bidirectional gear pump, drive shaft, closed fuel tank, and control valve block assembly are modularized. Arranged and connected by external piping.

The power unit is arranged in parallel with the execution cylinder, effectively reducing the axial arrangement space.

An integrated electro-hydraulic steering actuation unit (floating state) control method of the present invention is characterized in that the steps are as follows

(1) The bidirectional servo motor makes the execution cylinder move to the right:

(2) The bidirectional servo motor makes the execution cylinder move to the left:

(3) After the two-way servo motor stops, the position of the piston rod of the hydraulic cylinder is maintained through the check valves 3.3 and 3.4, the hydraulic control check valves 4.1 and 4.2, and the relief valves 5.3 and 5.4. The maximum pressure of the two chambers of the hydraulic cylinder is controlled by the overflow. Valves 5.3, 5.4 are set.

(4) After the motor stops, when the electromagnetic reversing valve 6 is energized, the communication between the left and right chambers of the oil cylinder is performed, and the actuator is in a floating state under the action of external force.

The advantages of the present invention compared with the prior art are:

(1) The present invention adopts an integrated electro-hydraulic steering actuating unit in the steering system of the special vehicle chassis, which can save the complex steering rod structure between the axles of each group, and can correspondingly save the hydraulic oil source, The steering cylinders of each axle, various control valves, and numerous hydraulic pipelines can also reduce the probability of leakage and leakage of the steering hydraulic system. The use of an integrated electro-hydraulic steering actuation unit has significant advantages.

(2) The present invention effectively reduces the axial arrangement space and facilitates installation by arranging the oil source of the integrated electro-hydraulic steering actuating unit in parallel with the execution oil cylinder.

(3) In the present invention, the modularized power unit and the actuator cylinder in the integrated electro-hydraulic steering actuating unit can be integrated into one body through screw connection, and can also be arranged separately according to the installation space, connected by external pipelines, and the installation method is flexible.

(4) In the present invention, the oil tank in the integrated electro-hydraulic steering actuating unit is designed as a closed hydraulic oil tank, and a closed structure is adopted to ensure that the two-way gear pump of the integrated electro-hydraulic steering actuating unit operates well under any working attitude. High oil absorption capacity, while effectively preventing excess material from entering the system.

(5) In the present invention, an electromagnetic reversing valve is arranged between the two cavities of the execution cylinder in the integrated electro-hydraulic steering actuating unit, so that under emergency conditions, the electromagnetic reversing valve is energized to realize the two cavities of the execution cylinder. The connection is in a floating working state, and the wheel can be aligned under external force, which effectively improves the safety of steering.

Description of drawings

Figure 1 is the hydraulic principle diagram of the integrated electro-hydraulic steering actuation unit.

Figure 2 is a structural diagram of an integrated electro-hydraulic steering actuating unit.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

The present invention relates to an integrated electro-hydraulic steering actuating unit and a control method. The actuating unit comprises: a bidirectional servo motor, a bidirectional gear pump, an actuating oil cylinder, a transmission shaft, a closed oil tank, and a control valve block assembly; an externally inputted control signal Control the rotation direction and speed of the bidirectional servo motor. The bidirectional servo motor drives the bidirectional gear pump to output the oil flow through the transmission shaft, thereby driving the extension direction and extension speed of the execution cylinder. The control valve block assembly is used to maintain the movement position of the oil cylinder when the two-way servo motor stops working, and can be used to perform the extension action of the oil cylinder. ;The control valve block assembly can limit the working pressure of the execution cylinder when the temperature of the execution cylinder or the load changes suddenly, and is used to set the maximum working pressure of the two-way gear pump, limit the output power of the two-way gear pump, and prevent the overload of the two-way servo motor; Control valve block The assembly can realize the connection between the two chambers of the execution cylinder and is in a floating working state, which improves the safety of the integrated electro-hydraulic steering actuating unit for steering work under emergency conditions.

The invention provides an integrated electro-hydraulic steering actuating unit, which can be used in the steering system of a special vehicle. The electric drive mode is adopted, and the left and right wheel steering swing arms of each axle are connected to an integrated electro-hydraulic steering actuating unit execution oil cylinder. The two lugs are independently driven by a single electro-hydraulic actuating unit to realize all-wheel independent drive steering, solve the problem of multi-mode steering of special vehicles, and have great significance for improving the overall performance of vehicle steering.

As shown in FIG. 2, an integrated electro-hydraulic steering actuation unit of the present invention includes: a bidirectional servo motor, a bidirectional gear pump, an execution oil cylinder (the execution oil cylinder is preferably a double-rod hydraulic cylinder), a transmission shaft, a closed oil tank, a control valve block assembly;

The external input control signal controls the rotation and speed of the bidirectional servo motor. The bidirectional servo motor drives the bidirectional gear pump to output the oil flow through the transmission shaft, thereby driving the extension direction and extension speed of the execution cylinder (preferably a double-rod hydraulic cylinder). .

Control valve block assembly, including: valve body, check valve, relief valve, hydraulic control check valve, electromagnetic directional valve; check valve, overflow valve, hydraulic control check valve, solenoid directional valve are installed in the In the valve body; the control valve block assembly is used to maintain the movement position of the oil cylinder when the two-way servo motor stops working, and can be used to perform the extension and retraction of the oil cylinder. The temperature of the liquid; the control valve block assembly can limit the working pressure of the execution cylinder when the temperature of the execution cylinder increases or the load suddenly changes, and is used to set the maximum working pressure of the bidirectional gear pump, limit the output power of the bidirectional gear pump, and prevent the bidirectional servo motor. Overloading; the control valve block assembly can realize the connection between the two chambers of the execution oil cylinder in a floating working state, and improve the reliability of the work.

The two oil ports of the bidirectional gear pump are provided with overflow valves, which are used to set the maximum working pressure of the oil source, limit the output power of the bidirectional gear pump, and prevent the bidirectional servo motor from overloading;

The two oil ports of the execution cylinder are provided with relief valves, which can limit the working pressure of the execution cylinder when the temperature of the execution cylinder increases or the load suddenly changes;

One-way valves are respectively set from the closed oil tank to the two oil ports of the two-way gear pump to realize the normal switching of the one-way pressure build-up and oil suction functions of the two-way gear pump.

The two chambers of the execution cylinder are respectively provided with hydraulic control check valves, which are used to return the oil on the return side to the closed tank to dissipate heat and reduce the temperature of the circulating working oil when the cylinder is extended and retracted.

An electromagnetic reversing valve is set between the two chambers of the execution cylinder. When the power is not available, the two working chambers of the execution cylinder are disconnected; when the power is turned on, the two working chambers of the execution cylinder are connected for emergency conditions , to achieve the two-chamber communication of the execution cylinder in a floating working state.

The closed oil tank is a closed hydraulic oil tank, which adopts a closed structure to ensure that the two-way gear pump has a good oil absorption capacity under any working posture of the integrated electro-hydraulic steering actuation unit.

The power unit and the actuator cylinder composed of the bidirectional servo motor, bidirectional gear pump, drive shaft, closed fuel tank, and control valve block assembly are modularized. Arranged and connected by external piping.

The invention fully considers the limitation of the installation space of the special vehicle chassis, and the power unit of the integrated electro-hydraulic steering actuating unit and the execution oil cylinder are modularly designed, and the two can be integrated into one by screwing, and can also be separated according to the specific installation space. The arrangement is connected by external pipelines, and the installation method is flexible. At the same time, by arranging the oil source of the integrated electro-hydraulic steering actuation unit in parallel with the execution cylinder, the axial arrangement space is effectively reduced and installation is facilitated. The power unit and the actuator cylinder composed of the bidirectional servo motor, bidirectional gear pump, drive shaft, closed fuel tank, and control valve block assembly are modularized. Arranged and connected by external piping.

As shown in FIG. 1, an integrated electro-hydraulic steering actuation unit of the present invention preferably includes: a check valve 3.3, a relief valve 5.1, a check valve 3.2, a hydraulic control check valve 4.2, a check valve Valve 3.4, Relief Valve 5.2, Hydraulic Control Check Valve 4.1, Check Valve 3.1, Relief Valve 5.3, Relief Valve 5.4, Electromagnetic Reversing Valve 6

The execution cylinder (the execution cylinder is preferably a double-rod hydraulic cylinder) moves to the right: the bidirectional servo motor 9 starts after receiving the right movement command, and the oil from the bidirectional gear pump 8 is supplied to the left cavity of the dual-rod hydraulic cylinder 1 through the check valve 3.3. Oil, the maximum thrust is set by the pump outlet relief valve 5.1, and the piston rod moves to the right; the return oil from the right chamber returns to the closed oil tank 2 through the hydraulic control check valve 4.2, and the oil suction port of the two-way gear pump 8 passes through the check valve 3.2. Oil is sucked from the closed oil tank 2, and the motor stops when the piston rod moves in place.

The execution cylinder (preferably a double-rod hydraulic cylinder) moves to the left: the two-way servo motor 9 starts after receiving the leftward movement command, and the oil from the two-way gear pump 8 supplies oil to the right cavity of the double-rod hydraulic cylinder 1 through the one-way valve 3.4, The maximum thrust is set by the pump outlet relief valve 5.2, and the piston rod moves to the left; the oil in the left cavity returns to the closed oil tank 2 through the hydraulic control check valve 4.1, and the oil suction port of the two-way gear pump 8 is closed through the check valve 3.1. The oil is sucked in the oil tank 2, and the motor stops when the piston rod moves in place.

After the motor stops, the position of the piston rod of the hydraulic cylinder is maintained through the check valves 3.3 and 3.4, the hydraulic control check valves 4.1 and 4.2, and the relief valves 5.3 and 5.4. The maximum pressure of the two chambers of the hydraulic cylinder is set by the relief valves 5.3 and 5.4. Certainly.

After the motor stops, when the electromagnetic reversing valve 6 is energized, the left and right chambers of the double-rod hydraulic cylinder 1 communicate with each other, and under the action of external force, the actuator can be in a floating state.

For an integrated electro-hydraulic steering actuating unit of the present invention, the preferred solution is: the maximum axial load of the execution oil cylinder is 62kN, the maximum running speed is 60mm/s, the median length is 840mm, and the stroke is 255mm. The preferred pressure range P of the execution cylinder is 0.07MPa≤P≤0.12MPa, which effectively ensures the oil absorption capacity of the bidirectional gear pump and the maximum movement speed of the integrated electro-hydraulic steering actuation unit.

The main working parameters of the bidirectional gear pump are shown in Table 1.

Table 1 Main working parameters of bidirectional gear pump

serial number parameter name parameter value Remark 1 Maximum working pressure P1/MPa 30 2 Intermittent working pressure P2/MPa 31 3 Maximum peak pressure P3/MPa 36 4 No-load maximum speed/rpm 4700 5 Minimum speed/rpm at P1 pressure 550 6 Oil suction pressure/MPa 0.07-0.3

The main working parameters of the servo motor are shown in Table 2.

Table 2 Main working parameters of servo motor

The product prototype test shows that the integrated electro-hydraulic steering actuating unit provided by the present invention can effectively realize the performance of the steering system of special vehicles. The performance indicators of the integrated electro-hydraulic steering actuating unit are shown in Table 3. The vehicle controller controls a single electro-hydraulic actuation unit to realize the all-wheel independent drive and steering of special vehicles, realizes multi-mode steering of the vehicle, and simplifies the complex steering system into the module construction of "new electro-hydraulic integrated steering actuation unit" to realize intelligent Modularization and rapid design of steering function of any shaft system of special vehicles. The performance indicators of the integrated electro-hydraulic steering actuation unit are shown in Table 3;

Table 3 Performance index of integrated electro-hydraulic steering actuation unit

serial number parameter name Performance test value Does it meet the requirements Remark 1 Maximum axial load/kN ≥60 62 Satisfy 2 Maximum speed mm/s ≥60 60 Satisfy 3 Folded length mm 840 840 Satisfy 4 stroke mm ≥220 255 Satisfy

Based on an integrated electro-hydraulic steering actuation unit (floating state) control method of the present invention, the steps are as follows

(1) The execution cylinder (the execution cylinder selects a double-rod hydraulic cylinder) moves to the right:

(1.1) The bidirectional servo motor 9 starts after receiving the rightward motion command, and the oil from the bidirectional gear pump 8 supplies oil to the left cavity of the dual-rod hydraulic cylinder 1 through the check valve 3.3.

(1.2) Set the maximum thrust of the two-way gear pump outlet relief valve 5.1, and the piston rod moves to the right

(1.3) Execute the oil return from the right chamber of the oil cylinder through the hydraulic control check valve 4.2 to return to the closed oil tank 2, while the oil suction port of the pump 8 sucks oil from the closed oil tank 2 through the check valve 3.2. When the piston rod moves in place, the motor stops ;

(2) Execute the cylinder (double-rod hydraulic cylinder) to move to the left:

(2.1) The bidirectional servo motor 9 starts after receiving the leftward motion command,

(2.2) The oil from the two-way gear pump 8 is supplied to the right chamber of the double-rod hydraulic cylinder 1 through the one-way valve 3.4,

(2.3) Set the maximum thrust of the two-way gear pump outlet relief valve 5.2, and the piston rod moves to the left; (2.4) The oil returned to the left cavity returns to the closed tank 2 through the hydraulic control check valve 4.1, and the oil suction port of the pump 8 passes through a single The valve 3.1 sucks oil from the closed tank 2, and the motor stops when the piston rod moves in place.

(3) After the motor stops, the position of the piston rod of the hydraulic cylinder is maintained through the check valves 3.3 and 3.4, the hydraulic control check valves 4.1 and 4.2, and the relief valves 5.3 and 5.4. The maximum pressure of the two chambers of the hydraulic cylinder is determined by the relief valve 5.3 , 5.4 Settings.

(4) After the motor stops, when the electromagnetic reversing valve 6 is energized, the left and right chambers of the double-rod hydraulic cylinder 1 communicate with each other. Under the action of external force, the actuator can be in a floating state.

In the above floating state control method, the valve body, check valve, relief valve, hydraulic control check valve and electromagnetic directional valve together form a control valve block assembly, check valve, overflow valve, hydraulic control check valve, The electromagnetic reversing valve is installed in the valve body; the two oil ports of the two-way gear pump are provided with overflow valves, which are used to set the maximum working pressure of the oil source, limit the output power of the two-way gear pump, and prevent the overload of the two-way servo motor; Two oil ports are provided with relief valves, which can limit the working pressure of the execution oil cylinder when the temperature of the execution oil cylinder rises or the load suddenly changes; the two oil ports from the closed oil tank to the two-way gear pump are respectively set with check valves to realize the single-way operation of the two-way gear pump. Normal switching to pressure build-up and oil suction functions. The two chambers of the execution cylinder are respectively provided with hydraulic control check valves, which are used to return the oil on the return side to the closed tank to dissipate heat and reduce the temperature of the circulating working oil when the cylinder is extended and retracted. An electromagnetic reversing valve is set between the two chambers of the execution cylinder. When the power is not available, the two working chambers of the execution cylinder are disconnected; when the power is turned on, the two working chambers of the execution cylinder are connected for emergency conditions , to achieve the two-chamber communication of the execution cylinder in a floating working state. The floating working state is: when the electromagnetic reversing valve in the control valve block assembly is energized, the execution oil cylinder can follow the movement under the load. Emergency conditions, including: bidirectional servo motor failure or bidirectional gear pump failure. The electric energy output by the bidirectional servo motor is converted into the pressure energy of the oil source through the bidirectional gear pump, and the extension and retraction of the oil cylinder is controlled by the oil source. The actuator cylinder adopts a double-rod hydraulic cylinder, which includes two oil chambers. One-way movement of the piston rod in the double-rod hydraulic cylinder is realized by feeding oil into one chamber and returning oil to the other chamber. The double-rod hydraulic cylinder includes: cylinder barrel, piston rod, end cover, support lug, and base; the cylinder barrel and the base are fixedly connected, and the piston rod passes through the cylinder barrel and the end covers at both ends of the cylinder barrel; the piston rod divides the cylinder barrel into two parts Part, strokes two oil chambers, and lugs are provided at both ends of the piston rod to connect with the external load. The closed oil tank is a closed hydraulic oil tank, which adopts a closed structure to ensure that the two-way gear pump has a good oil absorption capacity under any working posture of the integrated electro-hydraulic steering actuation unit. The power unit and the actuator cylinder composed of the bidirectional servo motor, bidirectional gear pump, drive shaft, closed fuel tank, and control valve block assembly are modularized. Arranged and connected by external piping. The power unit is arranged in parallel with the execution cylinder, effectively reducing the axial arrangement space.

The invention adopts an integrated electro-hydraulic steering actuation unit in the steering system of the special vehicle chassis, which can save the complicated steering rod system structure between each group of axles, and can correspondingly save the hydraulic oil source and the Steering cylinders, various control valves, and numerous hydraulic pipelines can also reduce the probability of leakage of the steering hydraulic system. The integrated electro-hydraulic steering actuation unit has significant advantages. By integrating the integrated electro-hydraulic steering actuation unit The oil source and the execution cylinder are arranged in parallel, which effectively reduces the axial arrangement space and facilitates installation.

In the present invention, the modularized power unit and the actuator cylinder in the integrated electro-hydraulic steering actuating unit can be integrated into one through screw connection, and can also be arranged separately according to the installation space, connected by external pipelines, and the installation method is flexible. The oil tank in the hydraulic steering actuation unit is designed as a closed hydraulic oil tank, which adopts a closed structure to ensure that the two-way gear pump of the integrated electro-hydraulic steering actuation unit has a good oil absorption capacity under any working posture, and at the same time effectively prevents excess objects. enter the system.

In the present invention, an electromagnetic reversing valve is arranged between the two cavities of the execution oil cylinder in the integrated electro-hydraulic steering actuating unit, so that the electromagnetic reversing valve is energized under emergency conditions, so that the communication between the two cavities of the executive oil cylinder is floating. In the working state, the wheels can be aligned under the external force, which effectively improves the safety of steering.

Claims (2)

1. An integrated electro-hydraulic steering actuation unit, characterized in that it comprises: a bidirectional servo motor, a bidirectional gear pump, an execution oil cylinder, a transmission shaft, a closed fuel tank, and a control valve block assembly; The control signal input from the outside controls the rotation and speed of the bidirectional servo motor. The bidirectional servo motor drives the bidirectional gear pump to output the oil flow through the transmission shaft, thereby driving the extension direction and extension speed of the execution cylinder; The control valve block assembly is used to maintain the movement position of the oil cylinder when the two-way servo motor stops working, and can be used to carry out the extension and retraction of the oil cylinder. The oil on the return side returns to the closed tank for heat dissipation and reduces the temperature of the oil ;The control valve block assembly can limit the working pressure of the execution cylinder when the temperature of the execution cylinder increases or the load suddenly changes, and is used to set the maximum working pressure of the bidirectional gear pump, limit the output power of the bidirectional gear pump, and prevent the bidirectional servo motor from overloading; control The valve block assembly can realize that all the cavities of the execution cylinder are connected in a floating working state, which improves the safety of the integrated electro-hydraulic steering actuating unit steering work under emergency conditions; Control valve block assembly, including: valve body, check valve, relief valve, hydraulic control check valve, electromagnetic reversing valve; Check valve, relief valve, hydraulic control check valve, electromagnetic reversing valve are installed in the valve body; The two oil ports of the bidirectional gear pump are provided with overflow valves, which are used to set the maximum working pressure of the oil source, limit the output power of the bidirectional gear pump, and prevent the bidirectional servo motor from overloading; The two oil ports of the execution cylinder are provided with relief valves, which can limit the working pressure of the execution cylinder when the temperature of the execution cylinder increases or the load suddenly changes; One-way valves are respectively set from the closed oil tank to the two oil ports of the two-way gear pump to realize the normal switching of the one-way pressure building and oil suction functions of the two-way gear pump; The two cavities of the execution cylinder are respectively provided with hydraulic control check valves, which are used to return the oil on the return side to the closed tank for heat dissipation when the cylinder is extended and retracted, thereby reducing the temperature of the circulating working oil; An electromagnetic reversing valve is set between the two chambers of the execution cylinder. When no power is available, the two working chambers of the execution cylinder are disconnected; when the power is turned on, the two working chambers of the execution cylinder are connected for emergency working conditions , to realize the two-chamber communication of the execution cylinder in a floating working state; When the electromagnetic reversing valve in the control valve block assembly is energized, the actuator cylinder can follow the movement under the load; Emergency conditions, including: failure of bidirectional servo motor or failure of bidirectional gear pump; The electric energy output by the bidirectional servo motor is converted into the pressure energy of the oil source through the bidirectional gear pump, and the extension and retraction of the oil cylinder is controlled by the oil source; The actuating cylinder adopts a double-rod hydraulic cylinder, including two oil chambers. One-way movement of the piston rod in the double-rod hydraulic cylinder is realized by feeding oil into one chamber and returning oil to the other chamber; Double-rod hydraulic cylinder, including: cylinder barrel, piston rod, end cover, support lug, base; The cylinder barrel and the base are fixedly connected, and the piston rod passes through the cylinder barrel and the end caps at both ends of the cylinder barrel; the piston rod divides the cylinder barrel into two parts, and the stroke is two oil chambers. The lugs are arranged at both ends of the piston rod to connect with the external load ; The closed oil tank is a closed hydraulic oil tank, which adopts a closed structure to ensure that the two-way gear pump has a good oil absorption capacity under any working posture of the integrated electro-hydraulic steering actuation unit; The power unit and the actuator cylinder composed of the bidirectional servo motor, bidirectional gear pump, drive shaft, closed fuel tank, and control valve block assembly are modularized. Layout, connected by external pipeline; The power unit is arranged in parallel with the execution cylinder, which effectively reduces the axial arrangement space; The steering actuation unit can be used in the steering system of special vehicles. It adopts the electric drive mode. The left and right wheel steering swing arms of each axle are connected to the two lugs of the execution cylinder of an integrated electro-hydraulic steering actuating unit, relying on a single electro-hydraulic steering arm. The actuating unit is independently driven to realize all-wheel independent driving and steering, and solve the problem of multi-mode steering of special vehicles; The steering actuation unit fully considers the limitation of the installation space of the special vehicle chassis, and the power unit and the execution cylinder of the integrated electro-hydraulic steering actuation unit are modularly designed, and the two can be integrated by screwing. The space is arranged separately and connected by external pipelines, and the installation method is flexible; at the same time, by arranging the oil source of the integrated electro-hydraulic steering actuation unit in parallel with the execution oil cylinder, the axial arrangement space is effectively reduced, which is convenient for installation; two-way servo motor, The power unit and the actuator cylinder composed of the bidirectional gear pump, transmission shaft, closed fuel tank, and control valve block assembly are modularized. The power unit and the actuator cylinder can be integrated into one through screw connection, or they can be arranged separately according to the installation space. pipeline connection; The integrated electro-hydraulic steering actuation unit further includes: a third check valve (3.3), a first relief valve (5.1), a second check valve (3.2), a second hydraulic control check valve (4.2), The fourth check valve (3.4), the second relief valve (5.2), the first hydraulic control check valve (4.1), the first check valve (3.1), the third relief valve (5.3), the fourth overflow valve flow valve (5.4), electromagnetic reversing valve (6); The control method for executing the rightward movement of the double-rod hydraulic cylinder is: the bidirectional servo motor (9) starts after receiving the rightward motion command, and the oil from the bidirectional gear pump (8) exits the double-rod through the third check valve (3.3). The left chamber of the hydraulic cylinder (1) supplies oil, and the maximum thrust is set by the first relief valve (5.1) at the pump outlet, and the piston rod moves to the right; The oil tank (2), meanwhile, the oil suction port of the two-way gear pump (8) sucks oil from the closed oil tank (2) through the second check valve (3.2). When the piston rod moves in place, the motor stops; Execute the leftward movement of the double-rod hydraulic cylinder: the bidirectional servo motor (9) starts after receiving the leftward movement command, and the oil output from the bidirectional gear pump (8) passes through the fourth check valve (3.4) to the double-rod hydraulic cylinder (1). ) The right chamber supplies oil, the maximum thrust is set by the second relief valve (5.2) at the pump outlet, and the piston rod moves to the left; the oil returning from the left chamber returns to the closed oil tank (2) through the first hydraulic control check valve (4.1). At the same time, the oil suction port of the bidirectional gear pump (8) sucks oil from the closed oil tank (2) through the first one-way valve (3.1), and the motor stops when the piston rod moves in place; The floating state control method of the integrated electro-hydraulic steering actuation unit is as follows: after the two-way servo motor stops, the third check valve (3.3), the fourth check valve (3.4), the first hydraulic control check valve ( 4.1), the second hydraulic control check valve (4.2), the third relief valve (5.3), and the fourth relief valve (5.4) to maintain the position of the piston rod of the hydraulic cylinder, and the maximum pressure of the two chambers of the hydraulic cylinder is determined by the third overflow valve. Set the flow valve (5.3) and the fourth relief valve (5.4); after the motor stops, when the electromagnetic reversing valve (6) is energized, the communication between the left and right chambers of the oil cylinder is performed, and under the action of external force, the operation is realized. Actuator floating state. 2. A control method for an integrated electro-hydraulic steering actuating unit, characterized in that it has three control modes, including: a control mode in which a double-rod hydraulic cylinder moves to the right, a control mode in which the dual-rod hydraulic cylinder moves to the left , the floating state control method of the integrated electro-hydraulic steering actuation unit; The control method for the rightward movement of the double-rod hydraulic cylinder is: The bidirectional servo motor (9) starts after receiving the rightward motion command, and the oil from the bidirectional gear pump (8) is supplied to the left cavity of the double-rod hydraulic cylinder (1) through the third check valve (3.3), and the maximum thrust is supplied by the pump. The first overflow valve (5.1) at the outlet is set, and the piston rod moves to the right; the oil returned to the right chamber is returned to the closed oil tank (2) through the second hydraulic control check valve (4.2), and the bidirectional gear pump (8) sucks oil at the same time. The port sucks oil from the closed oil tank (2) through the second check valve (3.2), and the motor stops when the piston rod moves in place; The control method for the leftward movement of the double-rod hydraulic cylinder is: The bidirectional servo motor (9) starts after receiving the leftward motion command. The oil from the bidirectional gear pump (8) is supplied to the right chamber of the double-rod hydraulic cylinder (1) through the fourth check valve (3.4), and the maximum thrust is supplied by the pump. The second overflow valve (5.2) at the outlet is set, and the piston rod moves to the left; the oil returned to the left cavity is returned to the closed oil tank (2) through the first hydraulic control check valve (4.1), and the oil is sucked by the bidirectional gear pump (8). The port sucks oil from the closed oil tank (2) through the first check valve (3.1), and when the piston rod moves in place, the motor stops; The floating state control method of the integrated electro-hydraulic steering actuating unit is: After the two-way servo motor stops, through the third check valve (3.3), the fourth check valve (3.4), the first hydraulic control check valve (4.1), the second hydraulic control check valve (4.2), the third overflow valve The flow valve (5.3) and the fourth relief valve (5.4) maintain the position of the piston rod of the hydraulic cylinder, and the maximum pressure of the two chambers of the hydraulic cylinder is set by the third relief valve (5.3) and the fourth relief valve (5.4); After the motor stops, when the electromagnetic reversing valve (6) is energized, the communication between the left and right chambers of the oil cylinder is performed, and the actuator is in a floating state under the action of external force.

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