Lightweight and braking brushless direct-current electric mechanism for braking system

Abstract

The invention relates to the technical field of airplane braking, in particular to a lightweight and braking brushless direct-current electric mechanism for a braking system, which comprises a shell assembly, a middle cover assembly, a motor rear cover and a motor front cover, a rotor is assembled and mounted in the shell assembly, and a cylindrical pin and a gear are arranged on the left part of the outer surface of the rotor; a brake clamp spring, a bistable brake, an adjusting gasket, a bearing cover screw, a bearing cover, a bearing clamp spring, a front bearing, a spring washer, a brake screw and a brake rotor key are assembled and installed in the motor front cover. According to the light-weight brushless direct-current electric mechanism capable of braking for the braking system, due to the light-weight design, the total weight of the motor can be effectively reduced, the total power of the system is reduced through a bistable brake assembled on the brushless direct-current electric mechanism, and the brushless direct-current electric mechanism can be widely applied to braking systems, guided missiles and high-end civil equipment; the method has considerable market prospect and popularization value.

Description

Technical Field

[0001] This invention relates to the field of aircraft braking technology, and in particular to a lightweight, brakeable brushless DC electric mechanism for a braking system. Background Technology

[0002] The braking system is a core subsystem that ensures the safe operation of equipment. Among them, the brushless DC electric motor is a key drive component that provides rotational power to the braking system. Its performance directly determines the reliability of the braking system. For aircraft braking systems, the brushless DC electric motor needs to achieve brake disc braking through the forward rotation drive system mechanism and achieve brake disc unlocking through the reverse rotation drive system mechanism. Therefore, in addition to providing sufficient braking torque to the braking system, the motor's own light weight and reliable and stable operation are particularly critical. This is directly related to the aircraft's payload, fuel consumption, and flight range.

[0003] However, existing brushless DC electric mechanisms used in braking systems lack lightweight design, increasing the weight of aircraft and other equipment and limiting flight range. Furthermore, many existing motors are equipped with traditional power-off brakes, which require continuous power to maintain the unlocked state. This constant energization during motor operation not only generates significant heat, raising the motor's operating temperature and affecting the lifespan and operational stability of surrounding components, but also results in substantial energy loss, increasing overall system power consumption and reducing energy efficiency. Therefore, we introduce a new lightweight, brakeable brushless DC electric mechanism for braking systems. Summary of the Invention

[0004] The main objective of this invention is to provide a lightweight, brakeable brushless DC electric mechanism for braking systems, which can effectively solve the problems in the prior art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A lightweight, brakeable brushless DC electric mechanism for a braking system includes a housing assembly, an intermediate cover assembly, a rear motor cover, and a front motor cover. A rotor is assembled inside the housing assembly, and a cylindrical pin and a gear are disposed on the left side of the rotor's outer surface. A brake retaining ring, a bistable brake, adjusting shims, bearing cover screws, a bearing cover, a bearing retaining ring, a front bearing, spring washers, brake screws, and a brake rotor key are assembled inside the front motor cover. A rear bearing, a disc spring, and a disc spring retaining ring are assembled inside the rear motor cover. The components include: a sensor rotor, a nut, a sensor rotor key, a circuit board assembly, a circuit board under-shield, and an O-ring; the bistable brake includes a spring, a flange, a brake disc, a splined bushing, a moving plate, screws, a positioning sleeve, a brake winding, a permanent magnet, and a base; the housing assembly includes a stator key, a shaped housing, a stator, a positioning pin, a painted protective surface, and an insulating film placement cavity; the intermediate cover assembly includes an aluminum alloy intermediate cover and a stainless steel sleeve; and the rotor includes a shaft, a front dynamic balance ring, a rotor sheath, a rear dynamic balance ring, a bushing, a rotor key, and a magnet.

[0006] Preferably, the front bearing adopts a four-corner positioning assembly structure, the upper edges of both sides of the front bearing are fixed to the housing assembly through bearing caps, and the lower edges of both sides of the front bearing are fixed to the rotor through bearing retaining rings, so as to stably limit the front bearing in the front bearing chamber.

[0007] Preferably, the rear bearing adopts a pre-tightening fixing structure, with one side of the lower edge of the rear bearing fixed by a rotor, and the other side of the upper edge of the rear bearing provided with pre-tightening force by a pair of mating disc springs.

[0008] Preferably, in the housing assembly, the stator and the irregular housing are restricted from rotating in the circumferential direction by a stator key, and a positioning pin is drilled and installed between the stator and the irregular housing to restrict the axial movement of the stator.

[0009] Preferably, the irregularly shaped housing is an integrated structure, with an insulating varnish sprayed on the surface near the stator winding end inside, and an insulating film placed inside the insulating film placement cavity.

[0010] Preferably, the irregularly shaped housing is provided with a fully enclosed lead wire channel, through which the motor stator lead wire and the circuit board assembly lead wire are led out, and the outlet of the lead wire channel is sealed with silicone rubber potting.

[0011] Preferably, the aluminum alloy intermediate cover and the stainless steel sleeve of the intermediate cover assembly are tightly bonded together as one unit through a high-pressure die-casting process.

[0012] Preferably, the permanent magnet in the bistable brake is a high-temperature resistant permanent magnet, and the bistable brake unlocks when a forward current is applied and remains unlocked after power is cut off, and locks when a reverse current is applied and remains locked after power is cut off.

[0013] Preferably, the rotor achieves dynamic balance adjustment through a shaft, a front dynamic balance ring, and a rear dynamic balance ring, with the front and rear dynamic balance rings respectively mounted on the outer sides of both ends of the shaft.

[0014] Preferably, the brake screw inside the motor front cover is assembled with a bistable brake, and the spring washer is elastically pressed and fixed to the bearing cover.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. Due to its lightweight design, this brushless DC electric mechanism can effectively reduce the total weight of the motor. The bistable brake installed in the mechanism reduces the total power of the system. It can be widely used in braking systems, missiles and high-end civilian equipment, and has considerable market prospects and promotion value. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of a lightweight, brakeable brushless DC electric mechanism for a braking system according to the present invention. Figure 2 This is a schematic diagram of the overall structure of a lightweight, brakeable brushless DC electric mechanism for a braking system according to the present invention. Figure 3 This is a schematic diagram of the overall structure of the housing assembly of a lightweight, brakeable brushless DC electric mechanism for a braking system according to the present invention. Figure 4 This is a schematic diagram of the overall structure of the intermediate cover assembly of a lightweight, brakeable brushless DC electric mechanism for a braking system according to the present invention. Figure 5 This is a schematic diagram of the overall structure of the rotor assembly of a lightweight, brakeable brushless DC electric mechanism for a braking system according to the present invention. Figure 6 This is a schematic diagram of the windings and circuit board grounding of a lightweight, brakeable brushless DC electric mechanism for a braking system according to the present invention. Figure 7 This is a schematic diagram of the grounding of the brake of a lightweight, brakeable brushless DC electric mechanism for a braking system according to the present invention.

[0017] In the diagram: 1. Cylindrical pin; 2. Gear; 3. Brake circlip; 4. Bistable brake; 401. Brake lead wire; 5. Adjusting shim; 6. Bearing cover screw; 7. Bearing cover; 8. Bearing circlip; 9. Front bearing; 10. Housing assembly; 11. Rear bearing; 12. Intermediate cover assembly; 13. Disc spring; 14. Disc spring circlip; 15. Sensor rotor; 16. Nut; 17. Sensor rotor key; 18. Circuit board assembly; 181. Circuit board assembly lead wire; 19. Circuit board lower shim; 20. Motor rear cover; 21. O-ring; 22. Spring washer; 23. Brake screw; 24. Motor front cover; 25. Brake rotor key; 26. Rotor; 41. Spring; 42. 43. Brake disc; 44. Splined bushing; 45. Moving plate; 46. Screw; 47. Positioning sleeve; 48. Brake winding; 49. Permanent magnet; 410. Base; 101. Stator key; 102. Irregularly shaped housing; 103. Stator; 1031. Stator winding lead wire; 104. Positioning pin; 105. Painted protective surface; 106. Insulating film placement cavity; 121. Aluminum alloy intermediate cover; 122. Stainless steel sleeve; 261. Shaft; 262. Front dynamic balance ring; 263. Rotor sleeve; 264. Rear dynamic balance ring; 265. Bushing; 266. Rotor key; 267. Magnet; 27. Metal shielding layer; 28. Overlapping wire; 29. ​​Binding point; 30. Welding point. Detailed Implementation

[0018] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0019] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] Please see Figure 1-7 The present invention provides a technical solution: A lightweight, brakeable brushless DC electric mechanism for a braking system includes a housing assembly 10, an intermediate cover assembly 12, a motor rear cover 20, and a motor front cover 24. A rotor 26 is installed inside the housing assembly 10. A cylindrical pin 1 and a gear 2 are provided on the left side of the outer surface of the rotor 26. A brake retaining ring 3, a bistable brake 4, an adjusting shim 5, a bearing cover screw 6, a bearing cover 7, a bearing retaining ring 8, a front bearing 9, a spring washer 22, a brake screw 23, and a brake rotor key 25 are installed inside the motor rear cover 20. A rear bearing 11, a disc spring 13, a disc spring retaining ring 14, a sensor rotor 15, a nut 16, and a sensor rotor key 17 are installed inside the motor rear cover 20. The circuit board assembly 18, circuit board under gasket 19, O-ring 21, bistable brake 4 including spring 41, flange 42, brake disc 43, spline bushing 44, moving plate 45, screw 46, positioning sleeve 47, brake winding 48, permanent magnet 49, base 410, housing assembly 10 including stator key 101, irregular housing 102, stator 103, positioning pin 104, painted protective surface 105, insulating film placement cavity 106, intermediate cover assembly 12 including aluminum alloy intermediate cover 121, stainless steel sleeve 122, rotor 26 including shaft 261, front dynamic balance ring 262, rotor sleeve 263, rear dynamic balance ring 264, bushing 265, rotor key 266, magnet 267.

[0022] In this embodiment, the front bearing 9 adopts a four-corner positioning assembly structure. The upper edges of both sides of the front bearing 9 are fixed to the housing assembly 10 through the bearing cover 7, and the lower edges of both sides of the front bearing 9 are fixed to the rotor 26 through the bearing retainer 8, so as to stably limit the front bearing 9 in the front bearing chamber. The rear bearing 11 adopts a pre-tightening fixing structure. The lower edge of one side of the rear bearing 11 is fixed through the rotor 26, and the upper edge of the other side of the rear bearing 11 is provided with pre-tightening force through a pair of mating disc springs 13. In the housing assembly 10, the stator 103 and the irregular housing 102 are restricted to circumferential rotation through the stator key 101, and a positioning pin 104 is drilled and installed between the stator 103 and the irregular housing 102 to restrict the axial movement of the stator 103. The irregular housing 102 is an integrated structure. The surface of its interior near the winding end of the stator 103 is sprayed with insulating varnish, and an insulating film is placed in the insulating film placement cavity 106.

[0023] Through the above solutions: the four-corner positioning structure of the front bearing 9 forms a three-dimensional limit from the upper and lower edges on both sides, effectively resisting vibration and impact, ensuring the constant length of the motor shaft extension end, and improving the reliability of the system connection; the pre-tightening fixation of the rear bearing 11 is balanced by the elastic pre-tightening force of the disc spring 13, balancing the severe vibration during braking operation, ensuring the smooth operation of the rotor 26, and adapting to harsh working conditions such as aircraft landing; the housing assembly 10 is positioned by the stator key 101 and the positioning pin 104, respectively limiting the circumferential rotation and axial movement of the stator 103, solving the assembly deviation problem caused by the high temperature expansion of the aluminum alloy irregular housing 102; the integrated irregular housing 102, combined with the spraying of insulating paint and the placement of insulating film, simplifies assembly, reduces weight, and improves the insulation performance of the motor, avoiding the risk of short circuit caused by the contact between the winding end and the housing.

[0024] In this embodiment, the irregularly shaped housing 102 is provided with a fully enclosed lead wire channel. The lead wires of the motor stator 103 and the lead wires of the circuit board assembly 18 are led out through this lead wire channel. The outlet of the lead wire channel is sealed with silicone rubber potting. The aluminum alloy intermediate cover 121 of the intermediate cover assembly 12 and the stainless steel sleeve 122 are tightly integrated by high pressure die casting process. The permanent magnet 49 in the bistable brake 4 is a high temperature resistant permanent magnet. The bistable brake 4 unlocks when a positive current is applied and remains unlocked after power failure. It locks when a reverse current is applied and remains locked after power failure. The rotor 26 achieves dynamic balance adjustment through the shaft 261, the front dynamic balance ring 262, and the rear dynamic balance ring 264. The front dynamic balance ring 262 and the rear dynamic balance ring 264 are respectively assembled on the outer sides of both ends of the shaft 261. The brake screw 23 in the motor front cover 24 is fitted with the spring washer 22 to achieve elastic pressing and fixing of the bistable brake 4 and the bearing cover 7.

[0025] Through the above solutions: a fully enclosed lead-out channel combined with silicone rubber potting achieves waterproof sealing of the lead-out wires, while changing the lead-out direction improves tensile strength and ensures line reliability in harsh environments; the intermediate cover assembly 12 adopts a high-pressure die-casting method combining dissimilar materials, taking into account the lightweight advantages of aluminum alloy and the dimensional stability of stainless steel, avoiding bearing slippage at high temperatures; the bistable brake 4 utilizes the magnetic holding characteristics of the high-temperature resistant permanent magnet 49 to achieve current-driven unlocking / locking and power-off retention, solving the drawbacks of traditional power-off braking that involves continuous power-on heating and high losses, and adapting to the intermittent braking requirements of the braking system; the rotor 26's dual dynamic balance ring design reduces vibration and noise during high-speed operation through balance adjustment at both ends; the elastic fit between the brake screw 23 and the spring washer 22 achieves flexible fixation of key components, avoiding loosening problems caused by vibration in rigid connections.

[0026] It should be noted that the present invention is a lightweight, brakeable brushless DC electric mechanism for a braking system. During use, the motor structure consists of the following components: cylindrical pin 1, gear 2, brake retainer 3, bistable brake 4, adjusting shim 5, bearing cover screw 6, bearing cover 7, bearing retainer 8, front bearing 9, housing assembly 10, rear bearing 11, intermediate cover assembly 12, disc spring 13, disc spring retainer 14, sensor rotor 15, nut 16, sensor rotor key 17, circuit board assembly 18, circuit board lower shim 19, motor rear cover 20, O-ring 21, spring washer 22, brake screw 23, motor front cover 24, brake rotor key 25, rotor 26, etc. The bistable brake 4 has a high-temperature resistant permanent magnet 49 inside. Applying a positive current can unlock the brake, and it can remain unlocked after power failure. Applying a reverse current can lock the brake, and it can remain locked after power failure. When the electric mechanism equipped with the bistable brake 4 is used in the braking system, it can unlock the brake before the motor is powered on and de-energize the brake. The brake remains unlocked during the operation of the motor, which solves the drawbacks of traditional power failure braking, such as heat generation and losses when powered on. The front bearing 9 is fixed on both upper edges by the bearing cover 7 and the housing assembly 10, and on both lower edges by the bearing retainer 8 and the rotor 26. The front bearing 9 is stably fixed in the front bearing housing by the four corner positioning assembly method, which ensures that the length of the motor shaft extension remains unchanged under vibration and impact, and improves the stability of the motor and system connection. The rear bearing 11 is fixed on one side of the lower edge by the rotor 26, and a pair of mating disc springs 13 provide preload force to the other side of the upper edge of the rear bearing 11. In response to the severe vibration and impact during the braking operation of the electric mechanism, the appropriate preload force can ensure the stable operation of the motor rotor 26 and ensure the reliability of the product when the aircraft lands. The housing assembly 10 prevents circumferential rotation by assembling a stator key 101 between the housing and the stator 103, and prevents axial movement of the stator 103 caused by excessive expansion of the aluminum alloy housing at high temperatures by drilling and installing a positioning pin 104 between the housing and the stator 103. The insulation performance of the electric mechanism is improved and the reliable operation of the product is ensured by spraying insulating paint on the inner surface of the housing near the winding end of the stator 103 and placing an insulating film in the insulating film placement cavity 106. The housing is an integrated irregular housing 102. Through the integrated housing, multiple components such as stator 103, rotor 26, and bistable brake 4 can be assembled onto the same housing component. While reducing the overall weight of the electric mechanism, the coaxiality of the assembly of different components is improved, and the abnormal noise caused by excessive coaxiality when the electric mechanism is running at high speed is reduced. The housing features a fully enclosed lead-out channel design, allowing the motor stator 103 lead-out wires and circuit board assembly 18 lead-out wires to be led out through the integrated housing's internal lead-out channel. By encapsulating the lead-out port with silicone rubber, the product can be waterproofed. The lead-out channel can bend the radially led-out wires into axially led-out wires, and changing the lead-out direction can improve the tensile strength of the lead-out wires. The intermediate cover assembly 12 consists of an inner stainless steel sleeve 122 and an outer aluminum alloy intermediate cover 121. The aluminum alloy intermediate cover 121 and the stainless steel sleeve 122 are tightly bonded together by high-pressure die casting. Compared with an all-stainless steel intermediate cover, this processing method can significantly reduce the overall weight. Compared with an all-aluminum alloy intermediate cover, it solves the problem of excessive expansion of the aluminum alloy bearing chamber at high temperatures, which leads to bearing slippage. While achieving weight reduction, the reliability of the product is still maintained.

[0027] The electric mechanism (including the lead wire 1801 of the circuit board assembly 18, the lead wire 1031 of the stator winding of the stator 103, and the lead wire 401 of the brake of the bistable brake 4) has a grounding structure. The terminal block is fixed to the housing or intermediate cover assembly by screws. The lap wire 28 is connected to the terminal block and the metal shielding layer 27 outside the product lead wire by welding (i.e., welding point 30) to ensure the electrical continuity of the product. The binding point 29 is formed by cotton thread and tied and fixed to achieve the grounding shielding design of the lead wire.

[0028] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A lightweight, brakeable brushless DC motor for a brake system, comprising a housing assembly (10), an intermediate cover assembly (12), a motor rear cover (20) and a motor front cover (24), characterized in that: The rotor (26) is assembled inside the shell assembly (10), and the outer surface of the left part of the rotor (26) is provided with a cylindrical pin (1) and a gear (2); the motor front cover (24) is internally assembled with a brake spring (3), a bistable brake (4), an adjusting washer (5), a bearing cover screw (6), a bearing cover (7), a bearing spring (8), a front bearing (9), and a spring washer (22), a brake screw (23), a brake rotor key (25); the motor rear cover (20) is internally assembled with a rear bearing (11), a disc spring (13), a disc spring spring (14), a sensor rotor (15), a nut (16), a sensor rotor key (17), a circuit board assembly (18), a circuit board lower washer (19), and an O-ring (21). The bistable brake (4) comprises a spring (41), a flange plate (42), a brake disc (43), a spline shaft sleeve (44), a moving plate (45), a screw (46), a positioning sleeve (47), a brake winding (48), a permanent magnet (49), and a base (410). The shell assembly (10) comprises a stator key (101), a special-shaped shell (102), a stator (103), a positioning pin (104), a paint protection surface (105), and an insulation film placement cavity (106). The intermediate cover assembly (12) comprises an aluminum alloy intermediate cover (121) and a stainless steel sleeve (122). The rotor (26) comprises a shaft body (261), a front dynamic balance ring (262), a rotor sleeve (263), a rear dynamic balance ring (264), a shaft sleeve (265), a rotor key (266), and a magnetic steel (267).

2. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The front bearing (9) adopts a four-corner positioning assembly structure, the upper sides of the two sides of the front bearing (9) are fixed with the shell assembly (10) through the bearing cover (7), and the lower sides of the two sides of the front bearing (9) are fixed with the rotor (26) through the bearing spring (8), so as to stably position the front bearing (9) in the front bearing chamber.

3. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The rear bearing (11) adopts a pre-tightening fixed structure, the lower side of one side of the rear bearing (11) is fixed with the rotor (26), and the upper side of the other side of the rear bearing (11) is provided with a pre-tightening force through a pair of oppositely assembled disc springs (13).

4. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: In the shell assembly (10), the stator (103) and the special-shaped shell (102) are limited to rotate in the circumferential direction through the stator key (101), and the stator (103) and the special-shaped shell (102) are provided with the positioning pin (104) through drilling and installation, so as to limit the axial movement of the stator (103).

5. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The special-shaped shell (102) is an integrated structure, the surface close to the winding end of the stator (103) is sprayed with insulating paint, and the insulation film placement cavity (106) is placed with an insulation film.

6. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The special-shaped shell (102) is provided with a fully-enclosed lead-out line channel, the lead-out line of the motor stator (103) and the lead-out line of the circuit board assembly (18) are led out through the lead-out line channel, and the outlet of the lead-out line channel is sealed by silicon rubber.

7. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The aluminum alloy middle cover (121) of the middle cover assembly (12) is tightly combined with the stainless steel sleeve (122) by a high-pressure die casting process.

8. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The permanent magnet (49) in the bistable brake (4) is a high-temperature-resistant permanent magnet, and the bistable brake (4) is unlocked by passing a forward current and remains unlocked after power failure, and is locked by passing a reverse current and remains locked after power failure.

9. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The rotor (26) is dynamically balanced by the shaft body (261), the front dynamic balance ring (262) and the rear dynamic balance ring (264), and the front dynamic balance ring (262) and the rear dynamic balance ring (264) are respectively assembled on the outer sides of the two ends of the shaft body (261).

10. The lightweight, brakeable brushless DC motor for a brake system according to claim 1, characterized by: The brake screw (23) in the motor front cover (24) is matched and assembled with the bistable brake (4), and the elastic pad (22) is elastically pressed and fixed with the bearing cover (7).

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