CN113294455A - Electro-hydraulic actuator for clutch and control method thereof - Google Patents

Abstract

The invention discloses an electro-hydraulic actuator for a clutch and a control method, wherein the electro-hydraulic actuator comprises: the driving mechanism is connected with the driving piston rod and is used for driving the driving piston to do piston motion in the driving cylinder body; the clutch comprises a driven hydraulic cylinder and a clutch, wherein the driven hydraulic cylinder comprises a driven cylinder body, a driven piston and a driven piston rod, the driven piston is located in the driven cylinder body, the driven piston rod is connected with the driven piston, the driving cylinder body is communicated with the driven cylinder body, the driving hydraulic cylinder is used for driving the driven piston to do piston motion in the driven cylinder body, and the driven piston rod is connected with the clutch and controls the combination or separation of the clutch. The invention does not need an oil pump to provide oil pressure in real time, the power of the driving mechanism is adjusted according to the required oil pressure, and the invention has the advantages of low power consumption, high efficiency, high response speed, low maintenance cost and the like.

Description

Electro-hydraulic actuator for clutch and control method thereof

Technical Field

The invention relates to the technical field of clutches, in particular to an electro-hydraulic actuator for a clutch and a control method thereof.

Background

At present, hydraulic valve plates are mostly adopted in clutch control mechanisms of the double-clutch transmission. For a traditional double-clutch transmission, a hydraulic execution system comprises a filter, an oil pump, a hydraulic valve body, a shifting piston, a clutch and the like. The oil pump is a power source of the whole hydraulic execution system and is a power load of the engine. In the prior art, a set of hydraulic execution system is provided with a mechanical oil pump, the typical displacement value of the mechanical oil pump is more than 12cc/r, and the mechanical oil pump is driven by an engine to provide pressure and flow for gear shifting, a clutch and lubrication. The mechanical oil pump has the characteristics of low design difficulty of an oil pump and a valve body, simple structure, low cost and simple manufacturing process. However, the energy consumption of the oil pump changes along with the rotating speed of the engine, the energy consumption of the oil pump is high in a high rotating speed interval of the engine, and the flow is surplus. According to measurement, one mechanical oil pump needs to consume about 2% of engine torque, and in order to meet the working requirement of a hydraulic execution system, the existing mechanical oil pump has the characteristics of high rotating speed, high oil output pressure and large oil output flow, so that the energy consumption of the oil pump is high, and finally the economic performance of the dual-clutch transmission is poor.

The hydraulic control modes of an oil pump and the like have the disadvantages of low response speed, low efficiency, high power consumption and the like, and the pressure control precision of the clutch is poor; on the other hand, traditional hydraulic valve body, clutch control mechanism such as oil pump need install inside the derailleur, comes as power medium through absorbing the inside derailleur oil of derailleur, and its cleanliness management and control effect is relatively poor, causes the valve block that arouses because of the cleanliness problem easily, failure mode such as oil pump wearing and tearing, and actuating mechanism installs inside the derailleur in addition, need disassemble the derailleur during its maintenance, and the maintenance cost is higher.

Disclosure of Invention

In order to overcome the defects and shortcomings in the prior art, the invention aims to provide an electro-hydraulic actuator for a clutch and a control method thereof, so as to solve the problems of high power consumption, low efficiency, slow response speed and high maintenance cost of a clutch control mechanism in the prior art.

The purpose of the invention is realized by the following technical scheme:

the invention provides an electro-hydraulic actuator for a clutch, comprising:

the first driving mechanism is connected with the first driving piston rod and is used for driving the first driving piston to do piston motion in the first driving cylinder body;

the first driven hydraulic cylinder comprises a first driven cylinder body, a first driven piston and a first driven piston rod, the first driven piston is located in the first driven cylinder body, the first driven piston rod is connected with the first driven piston, the first driving cylinder body is communicated with the first driven cylinder body, the first driving hydraulic cylinder is used for driving the first driven piston to do piston motion in the first driven cylinder body, and the first driven piston rod is connected with the first clutch and controls the combination or separation of the first clutch;

and the control circuit board is electrically connected with the first driving mechanism and controls the first driving mechanism to drive the first active piston to do piston motion in the first active cylinder body.

Further, the first driving mechanism comprises a first driving motor and a first planetary roller screw, the first planetary roller screw comprises a first screw and a first nut shell matched with the first screw, the first driving motor is connected with the first screw and is used for driving the first screw to rotate, and the first driving piston rod is connected with the first nut shell and moves along the axial direction of the first screw along with the first nut shell.

Furthermore, a first rotation angle sensor is arranged on the first driving motor, and the first rotation angle sensor is electrically connected with the control circuit board and used for monitoring the rotation angle of the first driving motor; and the first planetary roller screw is provided with a first displacement sensor, and the first displacement sensor is electrically connected with the control circuit board and is used for monitoring the displacement of the first nut shell.

Further, the electro-hydraulic actuator for the clutch further comprises:

the second driving mechanism is connected with the second driving piston rod and is used for driving the second driving piston to do piston motion in the second driving cylinder body;

the second driven hydraulic cylinder comprises a second driven cylinder body, a second driven piston and a second driven piston rod, the second driven piston is located in the second driven cylinder body, the second driven piston rod is connected with the second driven piston, the second driving cylinder body is communicated with the second driven cylinder body, the second driving hydraulic cylinder is used for driving the second driven piston to do piston motion in the second driven cylinder body, and the second driven piston rod is connected with the second clutch and controls the combination or separation of the second clutch;

the second driving mechanism is electrically connected with the control circuit board, and the control circuit board controls the second driving mechanism to drive the second active piston to do piston motion in the second active cylinder body.

Further, the second driving mechanism comprises a second driving motor and a second planetary roller screw, the second planetary roller screw comprises a second screw and a second nut shell matched with the second screw, the second driving motor is connected with the second screw and is used for driving the second screw to rotate, and the second driving piston rod is connected with the second nut shell and moves along the axial direction of the second screw along with the second nut shell.

Furthermore, a second rotation angle sensor is arranged on the second driving motor, and the second rotation angle sensor is electrically connected with the control circuit board and is used for monitoring the rotation angle of the second driving motor; and a second displacement sensor is arranged on the second planetary roller screw and is electrically connected with the control circuit board and used for monitoring the displacement of the second nut shell.

Furthermore, a first connecting pipe is arranged between the first driving cylinder and the first driven cylinder, a first pressure and temperature sensor is arranged on the first connecting pipe, and the first pressure and temperature sensor is electrically connected with the control circuit board and used for monitoring the oil temperature and the oil pressure in the first connecting pipe; the second driving cylinder body and the second driven cylinder body are provided with a second connecting pipe therebetween, the second connecting pipe is provided with a second pressure and temperature sensor, and the second pressure and temperature sensor is electrically connected with the control circuit board and used for monitoring the oil temperature and the oil pressure in the second connecting pipe.

Further, a first oil pot is arranged on the first driving cylinder body, and the first oil pot is communicated with the first driving cylinder body and used for supplementing hydraulic oil into the first driving cylinder body; and a second oil pot is arranged on the second driving cylinder body, and the second oil pot is communicated with the second driving cylinder body and is used for supplementing hydraulic oil into the second driving cylinder body.

Further, an air pressure balancer is arranged between the first driving cylinder and the second driving cylinder, and the air pressure balancer is used for balancing the air pressure at the tail of the first driving cylinder, the air pressure at the tail of the second driving cylinder and the air pressure of the external environment.

Further, be equipped with main control unit, auxiliary controller, TCU, motor driver and temperature sensor on the control circuit board, auxiliary controller the TCU motor driver and temperature sensor all with main control unit electric connection, auxiliary controller with TCU electric connection, auxiliary controller with whether main control unit detects the other side each other and normally works, motor driver respectively with first actuating mechanism with second actuating mechanism electric connection is used for control first actuating mechanism with second actuating mechanism normally works, temperature sensor with motor driver electric connection is used for the monitoring motor driver's temperature.

The invention also provides a control method of the electro-hydraulic actuator, which is used for the electro-hydraulic actuator for the clutch and comprises the following steps:

s1: inputting a requested pressure;

s2: detecting a first actual pressure, and calculating a first request displacement and a first request rotation angle according to the request pressure and the first actual pressure;

s3: controlling a driving mechanism to drive an active hydraulic cylinder to stretch according to the first request corner;

s4: detecting a first actual displacement of the hydraulic cylinder in a telescopic mode, and calculating a target pressure according to the first request displacement and the first actual displacement;

s5: detecting a second actual pressure and an actual oil temperature, and calculating a second request displacement and a second request rotation angle according to the second actual pressure, the actual oil temperature and the target pressure;

s6: controlling the driving mechanism to drive the active hydraulic cylinder to stretch according to the second request corner;

s7: detecting a second actual displacement of the hydraulic cylinder in a telescopic mode, and calculating a target pressure according to the second request displacement and the second actual displacement;

s8: the above steps S5 to S7 are repeated.

The invention has the beneficial effects that: the driving hydraulic cylinder is driven by the driving mechanism to do telescopic motion, the driving hydraulic cylinder is enabled to provide hydraulic pressure for the driven hydraulic cylinder, and therefore combination or separation of the clutch is controlled, the power of the driving mechanism is adjusted according to the hydraulic pressure of the demand, fixed power is not required to be provided for the driving hydraulic cylinder all the time, power consumption is reduced, efficiency is improved, and quick response is achieved.

Drawings

FIG. 1 is a schematic diagram of an electro-hydraulic actuator for a clutch according to the present invention;

FIG. 2 is a side view schematic of the dual clutch of the present invention;

FIG. 3 is a schematic diagram of the electrical circuit configuration of the electro-hydraulic actuator for the clutch of the present invention;

fig. 4 is a flow chart of a control method in the present invention.

In the figure: a control circuit board 10, a main controller 11, an auxiliary controller 12, a TCU13, a motor driver 14, a temperature sensor 15, a first driving mechanism 21, a first driving motor 211, a first rotation angle sensor 211a, a first planetary roller screw 212, a first screw 212a, a first nut housing 212b, a first displacement sensor 212c, a second driving mechanism 22, a second driving motor 221, a second rotation angle sensor 221a, a second planetary roller screw 222, a second screw 222a, a second nut housing 222b, a second displacement sensor 222c, a first driving hydraulic cylinder 31, a first driving cylinder body 311, a first driving piston 312, a first driving piston rod 313, a second driving hydraulic cylinder 32, a second driving cylinder body 321, a second driving piston 322, a second driving piston rod 323, a first driven hydraulic cylinder 41, a first driven cylinder body 411, a first driven piston 412, a first driven piston rod 413, a first driven hydraulic cylinder 413, a second driving hydraulic cylinder 32, a second driving cylinder body 321, a second driving piston 322, a second driving piston rod 323, a first driven hydraulic cylinder body 41, a first driven cylinder body 411, a first driven piston 412, a second driven piston rod 413, a second driven hydraulic cylinder body, The hydraulic control system comprises a second driven hydraulic cylinder 42, a second driven cylinder 421, a second driven piston 422, a second driven piston rod 423, a first clutch 51, a second clutch 52, a first connecting pipe 61, a first pressure and temperature sensor 611, a second connecting pipe 62, a second pressure and temperature sensor 621, a first oil pot 71, a second oil pot 72 and an air pressure balancer 80.

Detailed Description

To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description will be made on the specific implementation, structure, features and effects of the electro-hydraulic actuator for clutch and the control method thereof according to the present invention with reference to the accompanying drawings and preferred embodiments:

fig. 1 is a schematic structural view of an electro-hydraulic actuator for a clutch according to the present invention, fig. 2 is a schematic structural view of a side view of a dual clutch according to the present invention, and fig. 3 is a schematic structural view of a circuit of the electro-hydraulic actuator for a clutch according to the present invention.

As shown in fig. 1 to 3, the present invention provides an electro-hydraulic actuator for a clutch, including:

the first driving mechanism 21 is connected with the first driving piston rod 313 and is used for driving the first driving piston 312 to perform piston movement in the first driving cylinder 311;

the first driven hydraulic cylinder 41 comprises a first driven cylinder body 411, a first driven piston 412 positioned in the first driven cylinder body 411 and a first driven piston rod 413 connected with the first driven piston 412, the first driving cylinder body 311 is communicated with the first driven cylinder body 411, the first driving hydraulic cylinder 31 is used for driving the first driven piston 412 to perform piston motion in the first driven cylinder body 411, and the first driven piston rod 413 is connected with the first clutch 51 and controls the connection or the disconnection of the first clutch 51;

the control circuit board 10, the control circuit board 10 is electrically connected to the first driving mechanism 21, and controls the first driving mechanism 21 to drive the first driving piston 312 to perform piston movement in the first driving cylinder 311.

In this embodiment, the electro-hydraulic actuator for a clutch further includes:

the second driving mechanism 22 is connected with the second driving piston rod 323 and is used for driving the second driving piston 322 to make piston motion in the second driving cylinder 321;

the second driven hydraulic cylinder 42 comprises a second driven cylinder 421, a second driven piston 422 positioned in the second driven cylinder 421 and a second driven piston rod 423 connected with the second driven piston 422, the second driving cylinder 321 is communicated with the second driven cylinder 421, the second driving hydraulic cylinder 32 is used for driving the second driven piston 422 to perform piston motion in the second driven cylinder 421, and the second driven piston rod 423 is connected with the second clutch 52 and controls the connection or disconnection of the second clutch 52;

the second driving mechanism 22 is electrically connected to the control circuit board 10, and the control circuit board 10 controls the second driving mechanism 22 to drive the second driving piston 322 to perform piston movement in the second driving cylinder 321.

The power of the first drive mechanism 21 and the power of the second drive mechanism 22 may be the same or different at the same time, and the actual power is adjusted according to the required engagement pressure of the first clutch 51 and the second clutch 52.

The electro-hydraulic actuator in the embodiment is used for double clutches, and of course, the electro-hydraulic actuator can also be used for single clutches in other embodiments, namely, only one of the driving mechanism, the driving hydraulic cylinder, the driven hydraulic cylinder and the clutch is needed.

The invention drives the driving hydraulic cylinders (the first driving hydraulic cylinder 31 and the second driving hydraulic cylinder 32) to do telescopic motion through the driving mechanisms (the first driving mechanism 21 and the second driving mechanism 22) so that the driving hydraulic cylinders provide hydraulic pressure for the driven hydraulic cylinders (the first driven hydraulic cylinder 41 and the second driven hydraulic cylinder 42) to control the combination or separation of the clutches (the first clutch 51 and the second clutch 52), the power of the driving mechanisms is adjusted according to the required hydraulic pressure without providing fixed power for the driving hydraulic cylinders all the time, the power consumption is reduced, the efficiency is improved, the quick response is realized, the electrohydraulic actuator can be independently arranged outside the gearbox, the disassembly is convenient, the maintenance cost is reduced, the movable hydraulic cylinders are relatively sealed with the oil in the movable hydraulic cylinders, the mechanical structure in the gearbox is not required to be lubricated, and the cleanliness of the oil is ensured, the probability of failure is greatly reduced.

Further, the first driving mechanism 21 includes a first driving motor 211 and a first planetary roller screw 212, the first planetary roller screw 212 includes a first screw 212a and a first nut housing 212b engaged with the first screw 212a, the first driving motor 211 is connected with the first screw 212a and is used for driving the first screw 212a to rotate, and the first driving piston rod 313 is connected with the first nut housing 212b and moves along the axial direction of the first screw 212a along with the first nut housing 212 b.

The second driving mechanism 22 includes a second driving motor 221 and a second planetary roller screw 222, the second planetary roller screw 222 includes a second screw 222a and a second nut housing 222b engaged with the second screw 222a, the second driving motor 221 is connected with the second screw 222a and is used for driving the second screw 222a to rotate, and the second driving piston rod 323 is connected with the second nut housing 222b and follows the second nut housing 222b to move along the axial direction of the second screw 222 a.

The first driving motor 211 and the second driving motor 221 are preferably brushless motors, the first planetary roller screw 212 and the second planetary roller screw 222 are preferably differential planetary roller screws, and the planetary roller screws can convert the rotation motion of the driving motors into reciprocating linear motion. Through motor drive differential type planet roller lead screw to it is flexible to drive the initiative pneumatic cylinder, it has the fast advantage of response speed, and differential type planet roller lead screw can realize piston self-locking function moreover, makes the piston stop in arbitrary target location, under the fixed state of moment of torsion, the motor can realize the work of undercurrent quiescent condition, the theory of operation of hydrostatic mode (fluid sealing mode) does not exist hydraulic oil simultaneously and reveals, effectively reduce this actuating mechanism's consumption, promote control efficiency.

Further, a first rotation angle sensor 211a is disposed on the first driving motor 211, and the first rotation angle sensor 211a is electrically connected to the control circuit board 10 and is used for monitoring a rotation angle of the first driving motor 211; the first planetary roller screw 212 is provided with a first displacement sensor 212c, and the first displacement sensor 212c is electrically connected to the control circuit board 10 and is used for monitoring the displacement of the first nut housing 212 b.

A second rotation angle sensor 221a is arranged on the second driving motor 221, and the second rotation angle sensor 221a is electrically connected with the control circuit board 10 and used for monitoring the rotation angle of the second driving motor 221; the second planetary roller screw 222 is provided with a second displacement sensor 222c, and the second displacement sensor 222c is electrically connected with the control circuit board 10 and is used for monitoring the displacement of the second nut housing 222 b.

Wherein, the rotation angle detected by the rotation angle sensor (the first rotation angle sensor 211a, the second rotation angle sensor 221a) and the movement displacement detected by the displacement sensor (the first displacement sensor 212c, the second displacement sensor 222c) are verified against each other, because the planetary roller screws (the first screw 212a, the second screw 222a) and the nut housings (the first nut housing 212b, the second nut housing 222b) are matched by threads, and there is a gap between the threads, and there is a certain error. Theoretical displacement can be calculated through the turned angle, then theoretical displacement is compared through actual removal displacement, and then the turned angle of readjustment driving motor (first driving motor 211, second driving motor 221) to reduce the error that planet roller lead screw brought, thereby realized electro-hydraulic actuating mechanism's pressure high accuracy and adjusted, effectively promoted the torque precision of clutch, thereby improved the NVH level of derailleur greatly.

Further, a first connecting pipe 61 is arranged between the first driving cylinder 311 and the first driven cylinder 411, a first pressure and temperature sensor 611 is arranged on the first connecting pipe 61, and the first pressure and temperature sensor 611 is electrically connected with the control circuit board 10 and is used for monitoring the oil temperature and the oil pressure in the first connecting pipe 61; a second connection pipe 62 is disposed between the second driving cylinder 321 and the second driven cylinder 421, a second pressure and temperature sensor 621 is disposed on the second connection pipe 62, and the second pressure and temperature sensor 621 is electrically connected to the control circuit board 10 and is used for monitoring the oil temperature and the oil pressure in the second connection pipe 62. The pressure and temperature sensors (the first pressure and temperature sensor 611 and the second pressure and temperature sensor 621) are integrated, but of course, two sensors, namely, the pressure sensor and the temperature sensor, may be used for independent monitoring. Because the oil temperature also can have certain influence to the oil pressure, the oil pressure that pressure temperature sensor detected and oil temperature can carry out the check-up with displacement sensor, has further promoted electro-hydraulic actuator's pressure adjustment precision. The first master cylinder 311 and the first slave cylinder 411, and the second master cylinder 321 and the second slave cylinder 421 are regarded as one communicating vessel, respectively. Of course, in other embodiments, the first driving cylinder 311 and the first driven cylinder 411, and the second driving cylinder 321 and the second driven cylinder 421 may be integrally formed, i.e., a total cylinder.

Further, a first oil pot 71 is arranged on the first driving cylinder 311, and the first oil pot 71 is communicated with the first driving cylinder 311 and is used for supplementing hydraulic oil into the first driving cylinder 311; the second driving cylinder 321 is provided with a second oil pot 72, and the second oil pot 72 is communicated with the second driving cylinder 321 and is used for replenishing hydraulic oil into the second driving cylinder 321. When there is insufficient air or hydraulic oil in the hydraulic cylinder, the driving pistons (the first driving cylinder 311 and the second driving cylinder 321) can respectively retract to the ends of the hydraulic driving cylinder to perform air exhaust or oil supplement.

Further, an air pressure balancer 80 is disposed between the first driving cylinder 311 and the second driving cylinder 321, and the air pressure balancer 80 is used for balancing the air pressure at the tail of the first driving cylinder 311, the air pressure at the tail of the second driving cylinder 321, and the air pressure of the external environment. The air pressure balancer 80 is provided with a filter element therein to increase the effect of filtering dust. The end of the driving cylinder body facing the driving piston rod is a tail part, the driving cylinder body is sealed, so that dust is reduced, the inner wall of the driving cylinder body is damaged or the power of the driving motor is increased, but a cavity at the tail part of the driving cylinder body is sealed, and when the driving piston moves, air pressure changes, and the power of the driving motor is increased. By providing the air pressure balancer 80, not only dust can be prevented from entering, but also the air pressure in the active cylinder can be balanced.

As shown in fig. 2, the first slave cylinder 41 and the first clutch 51 are preferably of circular ring structures, and the second slave cylinder 42 and the second clutch 52 are preferably of circular structures, so that the dual clutch can be made more smooth when the engaging pressures of the first clutch 51 and the second clutch 52 are different.

As shown in fig. 3, the Control circuit board 10 is provided with a main controller 11, an auxiliary controller 12, a TCU (Transmission Control Unit) 13, a motor driver 14, and a temperature sensor 15. The auxiliary controller 12, the TCU13, the motor driver 14 and the temperature sensor 15 are all electrically connected with the main controller 11, the auxiliary controller 12 is electrically connected with the TCU13, the auxiliary controller 12 and the main controller 11 mutually detect whether the other side works normally, and when the auxiliary controller 12 detects that the main controller 11 works abnormally, an error fault is immediately reported to the TCU13, so that the response control of the electro-hydraulic actuator is immediately cut off, and accidents are prevented. Of course, the primary controller 11 may also report an error signal to the TCU13 from the secondary controller 12, thereby shutting off the electro-hydraulic actuator response control and ensuring that the system remains in a high level safety mode. For example, the main controller 11 and the sub-controller 12 mutually transmit a piece of processing data to the other side for processing, and when the result after the processing by the other side is wrong, it is judged that the other side is working abnormally.

The motor driver 14 is electrically connected to the first driving mechanism 21 and the second driving mechanism 22 respectively and is used for controlling the first driving mechanism 21 and the second driving mechanism 22 to work normally, and the temperature sensor 15 is electrically connected to the motor driver 14 and is used for monitoring the temperature of the motor driver 14. When abnormal working modes such as locked rotor and the like occur to the driving motor, the motor driver 14 generates high temperature, the temperature sensor 15 is arranged near the motor driver 14, the high temperature signal is input to the main controller 11 to give an alarm, the driving motor is cut off, and the safety level is effectively improved.

The main controller 11 is further electrically connected to the first rotation angle sensor 211a, the second rotation angle sensor 221a, the first displacement sensor 212c, the second displacement sensor 222c, the first pressure and temperature sensor 611, and the second pressure and temperature sensor 621, and processes a rotation angle signal detected by the rotation angle sensor, a displacement signal detected by the displacement sensor, and an oil pressure signal and an oil temperature signal detected by the pressure and temperature sensor.

In this embodiment, the electro-hydraulic actuator for the clutch may further include a power supply to supply power to the control circuit board 10 and the driving motor.

As shown in fig. 4, the present invention further provides a control method of an electro-hydraulic actuator, the control method being used for the electro-hydraulic actuator for a clutch as described above, the control method comprising:

s1: the requested pressure is input. When the user depresses the throttle or clutch, the TCU13 will calculate the desired combined pressure, i.e., the requested pressure, and then transmit the requested pressure to the master controller 11.

S2: a first actual pressure is detected, and a first requested displacement and a first requested rotational angle are calculated from the requested pressure and the first actual pressure. Specifically, the actual oil pressure at this time is detected by the pressure and temperature sensors (the first pressure and temperature sensor 611 and the second pressure and temperature sensor 621), the magnitude of the actual oil pressure and the magnitude of the requested pressure are compared, and the first requested displacement and the first requested rotational angle required to reach the requested pressure, that is, the angle at which the drive motor needs to rotate and the displacement at which the master piston needs to move, are calculated.

S3: and controlling the driving mechanism to drive the active hydraulic cylinder to stretch according to the first requested rotation angle. Specifically, the main controller 11 sends a first requested rotation angle to the motor driver 14, and the motor driver 14 controls the driving motor to rotate by a corresponding angle, and at this time, the actual displacement of the active piston may have an error from the first requested displacement.

S4: and detecting a first actual displacement of the hydraulic cylinder in a telescopic mode, and calculating the target pressure according to the first request displacement and the first actual displacement. Specifically, the actual displacement of the active piston movement is detected by the displacement sensor, and then the actual displacement of the active piston movement is compared with the first requested displacement and the target pressure is calculated, because of the error, the target pressure and the requested pressure are generally not the same, if pressurization is required, the target pressure is generally greater than the requested pressure, and if depressurization is required, the target pressure is generally less than the requested pressure.

S5: and detecting a second actual pressure and an actual oil temperature, and calculating a second requested displacement and a second requested rotation angle according to the second actual pressure, the actual oil temperature and the target pressure. The oil temperature and the oil pressure can be influenced mutually, the oil temperature at the moment is detected through the pressure temperature sensor, the target pressure and the second actual pressure are compared, and then the actual oil temperature is added to calculate the angle of the driving motor which needs to rotate and the displacement of the driving piston which needs to move.

S6: and controlling the driving mechanism to drive the active hydraulic cylinder to stretch according to the second requested rotation angle. Specifically, the main controller 11 sends the second requested rotation angle to the motor driver 14, and controls the driving motor to rotate by the corresponding angle through the motor driver 14 again, and at this time, the actual displacement of the active piston movement may have an error with the second requested displacement.

S7: and detecting the second actual displacement of the telescopic hydraulic cylinder, and calculating the target pressure according to the second request displacement and the second actual displacement. Specifically, the actual displacement of the active piston movement is detected by the displacement sensor, and then the magnitude of the actual displacement of the active piston movement is compared with the magnitude of the second requested displacement and the target pressure is calculated again.

S8: and repeating the steps S5 to S7, and forming a closed loop regulation by repeatedly calculating and updating the target pressure, so that the actual oil pressure is closer to the requested pressure, the pressure precision is effectively improved, the high-torque precision control of the clutch is realized, and the high accuracy and the high responsiveness of the system are ensured.

The control circuit board 10 can independently control the first clutch 51 and the second clutch 52, and the control of the first clutch 51 and the second clutch 52 can be independently controlled by the above control method without mutual interference.

In this document, the terms of upper, lower, left, right, front, rear and the like are used to define the positions of the structures in the drawings and the positions of the structures relative to each other, and are only used for the sake of clarity and convenience in technical solution. It is to be understood that the use of the directional terms should not be taken to limit the scope of the claims. It is also to be understood that the terms "first" and "second," etc., are used herein for descriptive purposes only and are not to be construed as limiting in number or order.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (11)

1. An electro-hydraulic actuator for a clutch, comprising:

a first driving mechanism (21) and a first driving hydraulic cylinder (31), wherein the first driving hydraulic cylinder (31) comprises a first driving cylinder body (311), a first driving piston (312) positioned in the first driving cylinder body (311), and a first driving piston rod (313) connected with the first driving piston (312), and the first driving mechanism (21) is connected with the first driving piston rod (313) and is used for driving the first driving piston (312) to perform piston movement in the first driving cylinder body (311);

the first driven hydraulic cylinder (41) comprises a first driven cylinder body (411), a first driven piston (412) located in the first driven cylinder body (411) and a first driven piston rod (413) connected with the first driven piston (412), the first driving cylinder body (311) is communicated with the first driven cylinder body (411), the first driving hydraulic cylinder (31) is used for driving the first driven piston (412) to perform piston movement in the first driven cylinder body (411), and the first driven piston rod (413) is connected with the first clutch (51) and controls the connection or the disconnection of the first clutch (51);

the control circuit board (10) is electrically connected with the first driving mechanism (21), and controls the first driving mechanism (21) to drive the first driving piston (312) to perform piston movement in the first driving cylinder (311).

2. The electro-hydraulic actuator for a clutch according to claim 1, characterized in that the first driving mechanism (21) comprises a first driving motor (211) and a first planetary roller screw (212), the first planetary roller screw (212) comprises a first screw (212a) and a first nut housing (212b) matched with the first screw (212a), the first driving motor (211) is connected with the first screw (212a) and used for driving the first screw (212a) to rotate, and the first driving piston rod (313) is connected with the first nut housing (212b) and follows the first nut housing (212b) to move along the axial direction of the first screw (212 a).

3. The electro-hydraulic actuator for the clutch according to claim 2, wherein a first rotation angle sensor (211a) is arranged on the first driving motor (211), and the first rotation angle sensor (211a) is electrically connected with the control circuit board (10) and is used for monitoring the rotation angle of the first driving motor (211); and a first displacement sensor (212c) is arranged on the first planetary roller screw (212), and the first displacement sensor (212c) is electrically connected with the control circuit board (10) and is used for monitoring the displacement of the first nut shell (212 b).

4. The electro-hydraulic actuator for a clutch of claim 1, further comprising:

a second driving mechanism (22) and a second driving hydraulic cylinder (32), wherein the second driving hydraulic cylinder (32) comprises a second driving cylinder body (321), a second driving piston (322) located in the second driving cylinder body (321), and a second driving piston rod (323) connected with the second driving piston (322), and the second driving mechanism (22) is connected with the second driving piston rod (323) and is used for driving the second driving piston (322) to make piston movement in the second driving cylinder body (321);

the second driven hydraulic cylinder (42) comprises a second driven cylinder body (421), a second driven piston (422) and a second driven piston rod (423), the second driven piston (422) is located in the second driven cylinder body (421), the second driven piston rod (423) is connected with the second driven piston (422), the second driving cylinder body (321) is communicated with the second driven cylinder body (421), the second driving hydraulic cylinder (32) is used for driving the second driven piston (422) to perform piston movement in the second driven cylinder body (421), and the second driven piston rod (423) is connected with the second clutch (52) and controls the connection or the disconnection of the second clutch (52);

the second driving mechanism (22) is electrically connected with the control circuit board (10), and the control circuit board (10) controls the second driving mechanism (22) to drive the second driving piston (322) to perform piston movement in the second driving cylinder (321).

5. The electro-hydraulic actuator for a clutch according to claim 4, characterized in that the second driving mechanism (22) comprises a second driving motor (221) and a second planetary roller screw (222), the second planetary roller screw (222) comprises a second screw (222a) and a second nut housing (222b) matched with the second screw (222a), the second driving motor (221) is connected with the second screw (222a) and used for driving the second screw (222a) to rotate, and the second driving piston rod (323) is connected with the second nut housing (222b) and follows the second nut housing (222b) to move along the axial direction of the second screw (222 a).

6. The electro-hydraulic actuator for the clutch according to claim 5, wherein a second rotation angle sensor (221a) is arranged on the second driving motor (221), and the second rotation angle sensor (221a) is electrically connected with the control circuit board (10) and is used for monitoring the rotation angle of the second driving motor (221); and a second displacement sensor (222c) is arranged on the second planetary roller screw (222), and the second displacement sensor (222c) is electrically connected with the control circuit board (10) and is used for monitoring the displacement of the second nut shell (222 b).

7. The electro-hydraulic actuator for the clutch according to claim 4, characterized in that a first connecting pipe (61) is arranged between the first driving cylinder (311) and the first driven cylinder (411), a first pressure and temperature sensor (611) is arranged on the first connecting pipe (61), and the first pressure and temperature sensor (611) is electrically connected with the control circuit board (10) and is used for monitoring oil temperature and oil pressure in the first connecting pipe (61); the second driving cylinder body (321) and the second driven cylinder body (421) are provided with a second connecting pipe (62) therebetween, the second connecting pipe (62) is provided with a second pressure and temperature sensor (621), the second pressure and temperature sensor (621) is electrically connected with the control circuit board (10) and is used for monitoring the oil temperature and the oil pressure in the second connecting pipe (62).

8. The electro-hydraulic actuator for the clutch according to claim 4, characterized in that a first oil pot (71) is arranged on the first driving cylinder (311), and the first oil pot (71) is communicated with the first driving cylinder (311) and is used for supplementing hydraulic oil into the first driving cylinder (311); and a second oil pot (72) is arranged on the second driving cylinder body (321), and the second oil pot (72) is communicated with the second driving cylinder body (321) and used for supplementing hydraulic oil into the second driving cylinder body (321).

9. The electro-hydraulic actuator for a clutch according to claim 4, characterized in that an air pressure balancer (80) is disposed between the first driving cylinder (311) and the second driving cylinder (321), and the air pressure balancer (80) is configured to balance the air pressure at the tail of the first driving cylinder (311), the air pressure at the tail of the second driving cylinder (321), and the air pressure in the external environment.

10. The electro-hydraulic actuator for the clutch according to claim 4, wherein a main controller (11), an auxiliary controller (12), a TCU (13), a motor driver (14) and a temperature sensor (15) are arranged on the control circuit board (10), the auxiliary controller (12), the TCU (13), the motor driver (14) and the temperature sensor (15) are electrically connected with the main controller (11), the auxiliary controller (12) is electrically connected with the TCU (13), the auxiliary controller (12) and the main controller (11) mutually detect whether the other side normally works, the motor driver (14) is respectively electrically connected with the first driving mechanism (21) and the second driving mechanism (22) and is used for controlling the first driving mechanism (21) and the second driving mechanism (22) to normally work, the temperature sensor (15) is electrically connected with the motor driver (14) and is used for monitoring the temperature of the motor driver (14).

11. A control method of an electro-hydraulic actuator for a clutch according to any one of claims 1 to 10, the control method comprising:

s1: inputting a requested pressure;

s2: detecting a first actual pressure, and calculating a first request displacement and a first request rotation angle according to the request pressure and the first actual pressure;

s3: controlling a driving mechanism to drive an active hydraulic cylinder to stretch according to the first request corner;

s4: detecting a first actual displacement of the hydraulic cylinder in a telescopic mode, and calculating a target pressure according to the first request displacement and the first actual displacement;

s5: detecting a second actual pressure and an actual oil temperature, and calculating a second request displacement and a second request rotation angle according to the second actual pressure, the actual oil temperature and the target pressure;

s6: controlling the driving mechanism to drive the active hydraulic cylinder to stretch according to the second request corner;

s7: detecting a second actual displacement of the hydraulic cylinder in a telescopic mode, and calculating a target pressure according to the second request displacement and the second actual displacement;

s8: the above steps S5 to S7 are repeated.

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