Electrical brake based on normal stress actuator and electromechanical actuator and control method

Abstract

This invention relates to an electric brake and control method based on a normal stress actuator and an electromechanical actuator. The electric brake includes a normal stress actuator, a brake disc, an electromechanical actuator, a brake controller, a servo controller, and a current controller. The brake controller selects an appropriate operating mode based on the current braking pressure, target braking pressure, warning braking pressure, and base braking pressure, thereby controlling the pressure exerted on the brake disc by the normal stress actuator and the electromechanical actuator to achieve precise braking of the wheels and suppression of disturbances. The method is used to execute the above process. This invention achieves braking by pressing the brake disc with a normal stress actuator and an electromechanical actuator. Since the normal stress actuator controls the pressure by changing the current, the regulation is more precise and suitable for fine adjustment. The brake controller first controls the electromechanical actuator to adjust the pressure to an approximate range, and then controls the actuator for fine adjustment.

Description

Technical Field

[0001] This invention relates to the field of electric braking technology, and in particular to an electric brake and control method based on a normal stress actuator and an electromechanical actuator. Background Technology

[0002] In aircraft electric braking systems, electromechanical actuators, with their advantages of compact structure and good maintainability, have gradually replaced hydraulic and electro-hydraulic actuators as the new linear actuators. They mainly consist of a motor and a mechanical actuator (reduction gear system and ball screw pair). During braking, the piston of the electromechanical actuator extends, compressing the brake disc and generating braking pressure, which is directly proportional to the braking force. However, due to the very high rigidity of the brake disc, even a very slight change in piston displacement during the process of the electromechanical actuator driving the piston to press against the brake disc can result in a very large change in braking pressure. Because the position control precision of the electromechanical actuator is limited, the control precision of the braking pressure is not high. Simultaneously, the brake disc is prone to frictional vibration during braking. Due to the limited control bandwidth of the electromechanical actuator, it cannot adjust the piston position in time to follow the vibration, leading to large fluctuations in braking pressure and affecting the stability of the braking force.

[0003] Chinese patent application CN118953674A discloses a closed-loop control method for brake pressure, including: Step 1, calculating and setting the corresponding curve of the output voltage of the command sensor and the brake pressure according to the technical requirements of the wheel brake system; Step 2, setting the median range of the dead zone current of the hydraulic servo to 0.8-1.2mA and the median range of the electronic zero-point voltage of the command sensor to 0.78-0.86mV as the starting point of the corresponding curve of the output voltage of the command sensor and the brake pressure; Step 3, setting the initial conditions for the pressure closed loop to enter, etc. This invention can ensure the stability of the brake pressure output, but it cannot precisely control the pressure and does not show how to restore it to normal when the pressure fluctuates greatly.

[0004] Therefore, providing an electric brake and control method that can precisely regulate pressure is an urgent problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art and provide an electric braking and control method based on a normal stress actuator and an electromechanical actuator.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] According to one aspect of the present invention, an electric brake based on a normal stress actuator and an electromechanical actuator is provided for an aircraft wheel. The electric brake includes a normal stress actuator, a brake disc, an electromechanical actuator, a brake controller, a servo controller, and a current controller. The normal stress actuator and the electromechanical actuator are respectively mounted symmetrically on both sides of the brake disc. The brake controller is connected to both the servo controller and the current controller. The servo controller is connected to the electromechanical actuator. The current controller is connected to the normal stress actuator. The electromechanical actuator detects the current braking pressure.

[0008] The brake controller selects the corresponding operating mode based on the current brake pressure, target brake pressure, warning brake pressure and base brake pressure, thereby controlling the pressure of the normal stress actuator and electromechanical actuator on the brake disc to achieve precise braking of the wheels and suppress disturbances.

[0009] As a preferred technical solution, the electric brake further includes a pressure plate and a bearing plate, the electromechanical actuator is mounted on the brake disc via the pressure plate, and the normal stress actuator is mounted on the brake disc via the bearing plate.

[0010] As a preferred technical solution, both the electromechanical actuator and the normal stress actuator include an output shaft. The output shaft of the electromechanical actuator is connected to the pressure plate, and the output shaft of the normal stress actuator is connected to the pressure plate.

[0011] As a preferred technical solution, the electromechanical actuator further includes a force sensor, which is mounted on the output shaft of the electromechanical actuator.

[0012] As a preferred technical solution, the electric brake further includes a brake housing, the brake disc includes a stationary disc and a moving disc, the moving disc is connected to the wheel, and the stationary disc is fixed to the brake housing.

[0013] According to another aspect of the present invention, a control method for an electric brake based on a normal stress actuator and an electromechanical actuator as described above is provided. The method selects a corresponding operating mode based on the current braking pressure, the target braking pressure, the warning braking pressure, and the base braking pressure to perform precise braking or suppress disturbances. The operating mode includes three modes.

[0014] Mode 1: The electromechanical actuator and the normal stress electromagnetic actuator work together, and the brake controller simultaneously sends commands to the current control appliance and the servo controller. Both the electromechanical actuator and the normal stress electromagnetic actuator are in working state, squeezing the brake disc.

[0015] Mode 2: The electromechanical actuator operates independently, the brake controller sends a command to the servo controller, and the electromechanical actuator is in working state, pressing the brake disc; the coil of the normal stress electromagnetic brake is not energized.

[0016] Mode 3: The normal stress electromagnetic actuator operates independently, the brake controller sends a command to the current controller, the electromechanical actuator operates in locked mode, and the normal stress electromagnetic brake is in working state, pressing the brake disc.

[0017] As a preferred technical solution, the braking process includes the following steps:

[0018] During braking, mode two is selected first. The brake controller sends a position control command to the servo controller, which then controls the output shaft of the electromechanical actuator to move and press the brake disc.

[0019] Then, the system is switched to mode three. After the output shaft of the electromechanical actuator moves into place, the electromechanical actuator stops. The brake controller sends a command to the current controller, and the current controller adjusts the coil current according to the command, thereby pressing the brake disc.

[0020] As a preferred technical solution, the disturbance suppression involves the following process:

[0021] S1. If the current braking pressure fluctuates within the range of the base braking pressure and the warning braking pressure, then select mode three.

[0022] S11. In mode three, if the braking pressure is greater than the target braking pressure, the coil current of the normal application actuator is reduced, and the output shaft of the normal application actuator releases the brake disc; if the braking pressure is less than the target braking pressure, the coil current of the normal application actuator is increased, and the output shaft of the normal application actuator presses against the brake disc.

[0023] As a preferred technical solution, the disturbance suppression further includes:

[0024] If the current braking pressure is lower than the base braking pressure, select mode one until the current braking pressure returns to the range of base braking pressure and warning braking pressure.

[0025] As a preferred technical solution, the disturbance suppression further includes:

[0026] If the current brake pressure is higher than the warning brake pressure, select mode one until the current brake pressure returns to the range between the base brake pressure and the warning brake pressure.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. This invention uses a normal stress actuator and an electromechanical actuator to compress the brake disc for braking. Since the normal stress actuator controls the pressure by changing the current, the regulation is more precise and suitable for fine adjustment. The brake controller first controls the electromechanical actuator to adjust the pressure to the approximate range, and then controls the actuator to make fine adjustments.

[0029] 2. This invention divides the working modes into three types based on the target braking pressure, the warning braking pressure, and the basic braking pressure. The appropriate mode is selected according to the current braking pressure to adjust the pressure, so that the braking pressure is always consistent with the target braking pressure, thus ensuring stable braking power.

[0030] 3. The target braking pressure, warning braking pressure, and basic braking pressure of this invention can all be set according to actual conditions. The appropriate mode can be selected to adjust the pressure based on the current braking pressure.

[0031] 4. The present invention provides a force sensor on the output shaft of the electromechanical actuator, which can better detect the pressure when the output shaft squeezes the brake disc.

[0032] 5. The normal stress actuator and the electromechanical actuator of the present invention are symmetrically installed on both sides of the brake disc, which facilitates pressure from both sides. The output shafts of the normal stress actuator and the electromechanical actuator are located on the same axis, ensuring structural safety. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0034] Figure 2 This is a schematic cross-sectional view of the overall structure of the present invention;

[0035] Figure 3 This is a schematic cross-sectional view of the electromechanical actuator of the present invention;

[0036] Figure 4 This is a schematic cross-sectional view of the normal stress electromagnetic actuator of the present invention;

[0037] Figure 5 This is a schematic diagram of the static disk structure of the present invention;

[0038] Figure 6 This is a schematic diagram of the moving disk structure of the present invention;

[0039] Figure 7 This is a schematic diagram of the brake housing structure of the present invention;

[0040] Figure 8 This is a schematic diagram of the actuator base structure of the present invention;

[0041] Figure 9 This is a schematic diagram of the outer cylinder structure of the present invention;

[0042] Figure 10 This is a schematic diagram of the piston structure of the present invention;

[0043] Figure 11 This is a schematic diagram of the output shaft structure of the present invention;

[0044] Figure 12 This is a schematic diagram of the control connection of the present invention;

[0045] Figure 13 This is a schematic diagram of the control process of the present invention.

[0046] 1. Normal stress actuator, 2. Stationary plate, 3. Moving plate, 4. Pressure plate, 5. Electromechanical actuator, 6. Actuator base assembly, 7. Pressure plate, 8. Brake housing, 9. Base cover, 10. Low-speed gear, 11. Locking nut, 12. Base, 13. Lower end cover, 14. Outer cylinder, 15. Piston, 16. Upper end cover, 17. Output shaft, 18. Force sensor, 19. High-speed gear, 20. Motor, 21. Bearing pressure plate, 22. Bearing assembly, 23. Lead screw nut, 24. Lead screw shaft, 25. Guide ring, 26-1. Stator housing, 26-2. Stator housing, 27-1. Stator, 27-2. Stator, 28-1. Coil, 28-2. Coil, 29. Guide ring, 30. Output shaft, 31. Round nut, 32. Guide ring, 33. Permanent magnet ring, 34. Mover armature. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0048] Because aircraft electric brakes have low pressure control precision and are susceptible to vibration disturbances leading to pressure fluctuations, this invention leverages the advantages of normal stress electromagnetic actuators, such as compact structure, fast response, and high force density. By integrating the normal stress electromagnetic actuator into the electric brake, it enables the normal stress electromagnetic actuator and the electromechanical actuator to work together to regulate brake pressure. The electromechanical actuator handles macroscopic movement, achieving coarse adjustment of brake pressure; the normal stress electromagnetic actuator handles micro-displacement and disturbance response, utilizing its high displacement accuracy and fast response to achieve precise brake pressure adjustment. Through the coordinated operation of the normal stress electromagnetic actuator and the electromechanical actuator, precise and stable control of brake pressure is achieved.

[0049] This invention provides an electric braking and control method based on a normal stress actuator and an electromechanical actuator. The invention achieves braking by pressing the brake disc with the normal stress actuator and the electromechanical actuator. Since the normal stress actuator controls pressure by changing the current, the regulation is more precise and suitable for fine adjustment. The brake controller first controls the electromechanical actuator to adjust the pressure to a general range, and then controls the actuator for fine adjustment. This invention has three operating modes based on the target braking pressure, the warning braking pressure, and the base braking pressure. The appropriate mode is selected based on the current braking pressure to adjust the pressure, ensuring that the braking pressure always remains consistent with the target braking pressure and guaranteeing stable braking power. The target braking pressure, warning braking pressure, and base braking pressure can all be set according to actual conditions, and the corresponding mode is selected to adjust the pressure based on the current braking pressure. This invention incorporates a force sensor on the output shaft of the electromechanical actuator, which can better detect the pressure when the output shaft presses against the brake disc. The normal stress actuator and the electromechanical actuator of the present invention are symmetrically installed on both sides of the brake disc to facilitate pressure from both sides. The output shafts of the normal stress actuator and the electromechanical actuator are located on the same axis to ensure structural safety.

[0050] Example 1

[0051] like Figure 1-11 The electric brake is based on a normal stress actuator and an electromechanical actuator. The electric brake is used for the wheels of an aircraft. The electric brake includes a normal stress actuator 1, a brake disc, an electromechanical actuator 5, a brake controller, a servo controller, and a current controller. The normal stress actuator 1 and the electromechanical actuator 5 are respectively installed on both sides of the brake disc and are symmetrical. The brake controller is connected to the servo controller and the current controller respectively. The servo controller is connected to the electromechanical actuator (5). The current controller is connected to the normal stress actuator 1. The electromechanical actuator 5 detects the current braking pressure.

[0052] The brake controller selects the corresponding working mode based on the current brake pressure, target brake pressure, warning brake pressure and basic brake pressure, thereby controlling the pressure of the normal stress actuator 1 and electromechanical actuator 5 on the brake disc, so as to achieve precise braking of the wheel and suppress disturbance.

[0053] The electric brake also includes a pressure plate 4 and a pressure plate 7. The electromechanical actuator 5 is mounted on the brake disc via the pressure plate 4, and the normal stress actuator 1 is mounted on the brake disc via the pressure plate 7.

[0054] Both the electromechanical actuator 5 and the normal stress actuator 1 include an output shaft. The output shaft of the electromechanical actuator 5 is connected to the pressure plate 4, and the output shaft of the normal stress actuator 1 is connected to the pressure plate 7.

[0055] The electromechanical actuator 5 also includes a force sensor 18, which is mounted on the output shaft of the electromechanical actuator 5.

[0056] The electric brake also includes a brake housing 8, and the brake disc includes a stationary disc 2 and a moving disc 3. The moving disc 3 is connected to the wheel, and the stationary disc 2 is fixed to the brake housing 8.

[0057] In this embodiment, the brake disc includes multiple disc-shaped brake discs, divided into a stationary disc 2 and a moving disc 3. The stationary disc 2 is fixed to the brake housing 8, and the moving disc 3 is fixedly connected to the wheel and rotates with the wheel. During braking, the output shaft of the normal stress electromagnetic actuator 1 or the electromechanical actuator 5 presses against the brake disc, generating braking pressure between the moving disc 3 and the stationary disc 2, which in turn generates friction. This friction causes the wheel to decelerate and eventually stop rotating. The normal stress electromagnetic actuator 1 and the electromechanical actuator 5 are installed on both sides of the brake housing 8, and both can press against the brake disc. The normal stress electromagnetic actuator 1 is connected to the brake housing 8 by bolts, and the electromechanical actuator 5 is connected to the actuator seat assembly 6 by bolts. The actuator seat assembly 6 is fixed to the brake housing 8 by bolts, and the output shafts of both the normal stress electromagnetic actuator 1 and the electromechanical actuator 5 point towards the brake disc. When the braking command is executed, the internal motor of the electromechanical actuator 5 drives the ball screw to move the actuator piston outward, thereby squeezing the brake pressure plate 4, and then squeezing the stationary plate and the moving plate. When the braking command is executed, the internal coil of the normal stress electromagnetic actuator 1 is energized, the moving armature is subjected to force and drives the output shaft to move outward, thereby squeezing the pressure plate 7, and then squeezing the stationary plate 2 and the moving plate 3.

[0058] Throughout the braking process, both the normal stress electromagnetic actuator 1 and the electromechanical actuator 5 can compress the brake disc to generate braking pressure. Among them, the electromechanical actuator 5 has a longer stroke, but its motion accuracy is lower than that of the normal stress electromagnetic actuator 1. The electromechanical actuator 5 is responsible for large-range movement and generating basic braking pressure. The normal stress actuator 1 has a fast response and high motion accuracy. After the electromechanical actuator 5 establishes the basic braking pressure, the normal stress actuator 1 is responsible for precise pressure adjustment and disturbance suppression.

[0059] Motor 20 is connected to lead screw shaft 24 via gears 10 and 19. Motor 20 drives lead screw shaft 24 to rotate, which in turn drives lead screw nut 23 and piston 15 to move linearly. The direction of piston 15's movement is related to the direction of motor 20's rotation. When piston 15 moves outward, output shaft 17, fixed on piston 15, applies pressure to pressure plate 4. Force sensor 18 is installed at the head of output shaft 17 to measure brake pressure. Lead screw nut 23 is fixed to piston 15, and piston 15 is fixed to output shaft 17 with screws. Lead screw nut 23, piston 15, and output shaft 17 are all installed inside outer cylinder 14. Outer cylinder 14 is bolted to upper end cover 16 and lower end cover 13. Guide ring 25 and bearing assembly 22 provide axial support for output shaft 17 and lead screw shaft 24. Bearing assembly 22 is embedded in lower end cover 13, and bearing pressure plate 21 is threadedly connected to lower end cover 13 to prevent bearing assembly 22 from dislodging. The locking nut 11 is located at the end of the lead screw and is connected to the lead screw 4 by threads. When the locking nut 21 is tightened, it will squeeze the inner ring of the bearing to prevent the lead screw shaft 24 from moving.

[0060] The output shaft 30 has a threaded section at its stepped end. The mover armature 34 is axially fixed to the output shaft 30 via a round nut 31. The output shaft 30 and the round nut 31 move together with the mover armature 34. An air gap δ is provided on each side of the mover armature 34 (the larger δ is, the smaller the output force; generally, δ is less than 1mm). The stator 27-1 and stator 27-2 have identical structures, both with internal slots. Coils 28-1 and 28-2 are installed in the slots of stator 27-1 and stator 27-2, respectively. Grooves are provided on the inner edges of the outer walls of stator 27-1 and stator 27-2. When stator 27-1 and stator 27-2 are assembled as a whole, the permanent magnet ring 33 is embedded in the groove. Guide rings 29 and 32 are installed on both sides of the output shaft 30. Guide rings 29 and 32 are embedded in the central holes of stator 27-1 and stator 27-2, respectively, providing axial support for the output shaft 30. Stator housings 26-1 and 26-2 have identical structures. During assembly, stator 27-1 is inserted into stator housing 26-1, and stator 27-2 is inserted into stator housing 26-2. Then, stator housings 26-1 and 26-2 are fixedly connected by bolts, tightening the internal components of the actuator. Openings are provided on the outer walls of stator housings 26-1, 26-2, 27-1, and 27-2 for leading out coil wires. The force on the mover armature 34 is related to the current in coils 28-1 and 28-2, and the axial air gap length on both sides of the mover armature 34. By controlling the coil current, the force on the mover armature can be adjusted, thereby controlling the actuator output force.

[0061] The magnetomotive force of the permanent magnet ring 33 is radial, pointing from the outer ring of the actuator to the inner ring. The magnetic flux generated by the permanent magnet enters the mover armature 34 radially, and then enters the stator 27-1 and 27-2 from both sides of the armature, finally returning to the permanent magnet ring 33 through the stator to form a complete magnetic circuit. Therefore, the magnetic flux induced by the permanent magnet ring 33 in the air gaps on both sides of the armature is in opposite directions. The axial air gaps on both sides of the mover armature will change with the movement of the mover armature, but their sum remains constant. When the axial air gaps on both sides of the mover armature 34 are equal (both are δ), the magnetic field strength in the two air gaps is the same, and the resultant force of the mover armature 34 is 0. When the axial air gaps on both sides of the mover armature 34 are not equal (the sum is 2δ), the magnetic field strength in the two air gaps is no longer the same, and the normal electromagnetic force on one side of the armature surface will be greater than that on the other side, and the resultant force is no longer 0. When coils 28-1 and 28-2 are energized, the direction of the generated magnetizing flux is determined by the direction of the winding current, but the direction of the magnetizing flux in the air gaps on both sides of the armature is the same. Therefore, the magnetizing flux and the flux induced by the permanent magnet ring 33 are superimposed on one side of the armature air gap and canceled out on the other side, causing a change in the resultant normal electromagnetic force on both sides of the armature surface. The resultant normal electromagnetic force on both sides of the armature surface is the output force, which can be adjusted by regulating the coil current.

[0062] Example 2

[0063] like Figure 12 and Figure 13 As shown, a control method for electric braking based on a normal stress actuator and an electromechanical actuator is disclosed. The method selects an appropriate operating mode according to the current braking pressure, the target braking pressure, the warning braking pressure and the base braking pressure to perform precise braking or suppress disturbances. The operating mode includes three modes.

[0064] Mode 1: The electromechanical actuator 5 and the normal stress electromagnetic actuator 1 work together, and the brake controller simultaneously sends commands to the current control appliance and the servo controller. Both the electromechanical actuator 5 and the normal stress electromagnetic actuator 1 are in working state, squeezing the brake disc.

[0065] Mode 2: The electromechanical actuator 5 operates independently, the brake controller sends a command to the servo controller, and the electromechanical actuator 5 is in working state, pressing the brake disc; the coil of the normal stress electromagnetic brake 1 is not energized.

[0066] Mode 3: The normal stress electromagnetic actuator 1 operates independently, the brake controller sends a command to the current controller, the electromechanical actuator 5 operates in the locked mode, and the normal stress electromagnetic brake 1 is in the working state, pressing the brake disc.

[0067] In this embodiment, the brake consists of several braking units, each including a brake controller, a current controller, a servo controller, a normal stress electromagnetic actuator, and an electromechanical actuator. The brake controller receives commands from the flight control system, initiates the braking action according to the commands, and sets the target braking pressure. The current controller adjusts the output force of the normal stress electromagnetic actuator by controlling the coil current, and the servo controller adjusts the output shaft position of the electromechanical actuator by controlling the motor position. Based on the target braking pressure and the current braking pressure, the brake controller calculates and determines the target current of the current controller and the target position of the servo controller according to the control algorithm. The current controller and the servo controller operate according to the commands of the brake controller.

[0068] Mode 1 (i.e.) Figure 13 Section I): The electromechanical actuator and the axial stress electromagnetic actuator work together.

[0069] The brake controller simultaneously sends commands to the current control appliance and the servo controller (where the current control appliance receives the current control command and the servo controller receives the position control command; the commands can be transmitted via analog signals or digital protocols such as EtherCAT). The electromechanical actuator operates in position control mode, and the normal stress electromagnetic actuator operates in current control mode.

[0070] Mode 2 ( Figure 13 Section II): Electromechanical actuator working independently

[0071] The brake controller sends commands to the servo controller, and the electromechanical actuator operates in position control mode; the coil of the normal stress electromagnetic brake is not energized, and the output shaft can move under the action of external force.

[0072] Mode 3 ( Figure 13 Section III): Normal stress electromagnetic actuator operating independently

[0073] The brake controller sends a command to the current controller, and the electromechanical actuator operates in locked mode. The motor is not energized but is locked in a specific position, and the output shaft cannot move under external force. The normal stress electromagnetic brake operates in current control mode.

[0074] The braking process includes the following steps:

[0075] During braking, mode two is selected first. The brake controller sends a position control command to the servo controller. The servo controller controls the output shaft of the electromechanical actuator 5 to move and press the brake disc.

[0076] Then, the system is switched to mode three. After the output shaft of the electromechanical actuator 5 moves into place, the electromechanical actuator 5 stops. The brake controller sends a command to the current controller, and the current controller adjusts the coil current according to the command, thereby pressing the brake disc.

[0077] In this embodiment, during braking, the brake controller switches between three operating modes based on the target braking pressure and the current braking pressure. Upon receiving a braking pressure command, the brake controller sends a position control command to the servo controller and adjusts the position control command based on the target braking pressure and braking pressure feedback. The servo controller adjusts the motor speed according to the position control command and position feedback, driving the actuator output shaft to move. As the actuator output shaft moves outward, the brake discs are gradually pressed together, and the braking force continuously increases. At this time, the normal stress electromagnetic brake is not working, and its output shaft is squeezed by the brake discs to an extreme position far away from the brake discs. Braking is operating in mode two.

[0078] Once the braking force reaches the base braking pressure, due to the extremely high rigidity of the brake disc, the stroke required to reach the target braking pressure is very small. At this point, the system switches to operating mode three, the electromechanical actuator stops working, and the output shaft remains stationary. The brake controller sends a command to the current controller and adjusts the current control command according to the target braking pressure. The current controller adjusts the coil current according to the current control command until the target braking pressure is reached.

[0079] The disturbance suppression involves the following process:

[0080] S1. If the current braking pressure fluctuates within the range of the base braking pressure and the warning braking pressure, then select mode three.

[0081] S11. In mode three, if the braking pressure is greater than the target braking pressure, the coil current of the normal application actuator (1) is reduced, and the output shaft of the normal application actuator (1) releases the brake disc; if the braking pressure is less than the target braking pressure, the coil current of the normal application actuator (1) is increased, and the output shaft of the normal application actuator (1) squeezes the brake disc.

[0082] The disturbance suppression also includes:

[0083] If the current braking pressure is lower than the base braking pressure, select mode one until the current braking pressure returns to the range of base braking pressure and warning braking pressure.

[0084] The disturbance suppression also includes:

[0085] If the current brake pressure is higher than the warning brake pressure, select mode one until the current brake pressure returns to the range between the base brake pressure and the warning brake pressure.

[0086] In this embodiment, the brake disc vibrates violently due to friction, causing disturbances in the braking system and resulting in brake pressure fluctuations. The response to these fluctuations can be categorized into three cases:

[0087] 1) The fluctuation range is within the range of the basic braking pressure and the warning braking pressure: it still works in mode three; specifically: if the current braking pressure is greater than the target braking pressure, the actuator coil current is reduced and the actuator output shaft releases the brake disc; if the braking pressure is less than the target braking pressure, the actuator coil current is increased and the actuator output shaft squeezes the brake disc.

[0088] 2) The fluctuation causes the current braking pressure to be lower than the base braking pressure: Adjust to mode one, the electromechanical actuator outputs the axial brake disc to move, and at the same time, the actuator coil current is increased; when the braking pressure returns to the range of base braking pressure and warning braking pressure, adjust to mode three, increase the actuator coil current, and the actuator outputs the axial brake disc to squeeze.

[0089] 3) The fluctuation causes the current braking pressure to be higher than the warning braking pressure: Adjust to mode one, the electromechanical actuator output shaft releases the brake disc, and at the same time, the actuator coil current is reduced; when the braking pressure returns to the range of the basic braking pressure and the warning braking pressure, adjust to mode three, continue to reduce the actuator coil current, and the actuator output shaft releases the brake disc.

[0090] The target braking pressure needs to be set according to specific requirements. The target braking pressure is generated by the aircraft's overall control system and varies from aircraft to aircraft. The base braking pressure is set to 0.9 times the target braking pressure, and the warning braking pressure is set to 1.1 times the target braking pressure.

[0091] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An electric brake based on a normal stress actuator and an electromechanical actuator, said electric brake being used for aircraft wheels, characterized in that, The electric brake includes a normal stress actuator (1), a brake disc, an electromechanical actuator (5), a brake controller, a servo controller, and a current controller. The normal stress actuator (1) and the electromechanical actuator (5) are respectively installed on both sides of the brake disc and are symmetrical. The brake controller is connected to the servo controller and the current controller respectively. The servo controller is connected to the electromechanical actuator (5). The current controller is connected to the normal stress actuator (1). The electromechanical actuator (5) detects the current brake pressure. The brake controller selects the corresponding working mode according to the current brake pressure, target brake pressure, warning brake pressure and basic brake pressure, thereby controlling the pressure of the normal stress actuator (1) and electromechanical actuator (5) on the brake disc, so as to achieve precise braking of the wheel and suppress disturbance. The working mode includes three modes; Mode 1: The electromechanical actuator (5) and the normal stress actuator (1) work together, and the brake controller simultaneously sends instructions to the current control appliance and the servo controller. The electromechanical actuator (5) and the normal stress actuator (1) are both in working state, squeezing the brake disc. Mode 2: The electromechanical actuator (5) works independently, the brake controller sends a command to the servo controller, the electromechanical actuator (5) is in working state and squeezes the brake disc; the coil of the normal stress actuator (1) is not energized; Mode 3: The normal stress actuator (1) works alone, the brake controller sends a command to the current controller, the electromechanical actuator (5) works in the locked mode, and the normal stress actuator (1) is in the working state to squeeze the brake disc; The precise braking process includes the following steps: During braking, mode two is selected first. The brake controller sends a position control command to the servo controller. The servo controller controls the output shaft of the electromechanical actuator (5) to move and press the brake disc. Then, the mode is adjusted to mode three. After the output shaft of the electromechanical actuator (5) moves into place, the electromechanical actuator (5) stops. The brake controller sends a command to the current controller, and the current controller adjusts the coil current according to the command, thereby pressing the brake disc.

2. An electric brake based on a normal stress actuator and an electromechanical actuator according to claim 1, characterized in that, The electric brake also includes a pressure plate (4) and a pressure plate (7). The electromechanical actuator (5) is mounted on the brake disc via the pressure plate (4), and the normal stress actuator (1) is mounted on the brake disc via the pressure plate (7).

3. An electric brake based on a normal stress actuator and an electromechanical actuator according to claim 2, characterized in that, Both the electromechanical actuator (5) and the normal stress actuator (1) include an output shaft. The output shaft of the electromechanical actuator (5) is connected to the pressure plate (4), and the output shaft of the normal stress actuator (1) is connected to the pressure plate (7).

4. An electric brake based on a normal stress actuator and an electromechanical actuator according to claim 3, characterized in that, The electromechanical actuator (5) also includes a force sensor (18), which is mounted on the output shaft of the electromechanical actuator (5).

5. An electric brake based on a normal stress actuator and an electromechanical actuator according to claim 2, characterized in that, The electric brake also includes a brake housing (8), the brake disc includes a stationary disc (2) and a moving disc (3), the moving disc (3) is connected to the wheel, and the stationary disc (2) is fixed to the brake housing (8).

6. An electric brake based on a normal stress actuator and an electromechanical actuator according to claim 1, characterized in that, The disturbance suppression process involves the following steps: S1. If the current braking pressure fluctuates within the range of the base braking pressure and the warning braking pressure, then select mode three. S11. In mode three, if the braking pressure is greater than the target braking pressure, the coil current of the normal stress actuator (1) is reduced, and the output shaft of the normal stress actuator (1) releases the brake disc; if the braking pressure is less than the target braking pressure, the coil current of the normal stress actuator (1) is increased, and the output shaft of the normal stress actuator (1) squeezes the brake disc.

7. An electric brake based on a normal stress actuator and an electromechanical actuator according to claim 1, characterized in that, The disturbance suppression also includes: If the current braking pressure is lower than the base braking pressure, select mode one until the current braking pressure returns to the range of base braking pressure and warning braking pressure.

8. An electric brake based on a normal stress actuator and an electromechanical actuator according to claim 1, characterized in that, The disturbance suppression also includes: If the current brake pressure is higher than the warning brake pressure, select mode one until the current brake pressure returns to the range between the base brake pressure and the warning brake pressure.

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