A brushless servo motor

Abstract

The utility model discloses a kind of brushless rudder, including shell and the brushless motor being set in shell, reduction gear set, output shaft and output position detection assembly, the inner bottom surface of shell is shaped with motor fixed column, brushless motor is set on motor fixed column, the lower portion of shell is provided with PCB board, PCB board is below brushless motor, the side of PCB board towards brushless motor is provided with motor position detection assembly for detecting outer rotor assembly position, motor position detection assembly is below the outer rotor assembly. Brushless motor is directly integrated in shell structure to form integrated structure, without stator shell, simplify structure, reduce cost, reduce the overall thickness of brushless rudder;Motor position detection assembly is integrated on the PCB board below, realize the axial direction space multiplexing of brushless motor and motor position detection assembly;There is only one PCB board, without wire connection, reduce the risk of breakage, enhance shock resistance, improve reliability and stability.

Description

Technical Field

[0001] This utility model relates to the field of servo motor technology, and in particular to a brushless servo motor. Background Technology

[0002] A servo motor is a position (angle) servo drive suitable for control systems that require continuous angle changes and the ability to maintain that angle. A servo motor typically consists of an output shaft, a reduction gear set, and a motor. The motor drives the output shaft to rotate after being reduced in speed by the reduction gear set. Traditionally, servos can be categorized into brushed servos and brushless servos based on the type of motor used. Brushless servos use brushless motors for driving, and compared to brushed servos driven by brushed motors, brushless servos offer higher efficiency, higher control precision, and longer lifespan.

[0003] Most existing brushless servos have independently mounted brushless motors with built-in position sensing mechanisms. The brushless motor is directly connected to the servo's PCB board, resulting in a large size and requiring significant installation space, thus increasing the overall size of the brushless servo. Some brushless motors externalize the position sensing mechanism and connect it to the servo's PCB board via wires, reducing the motor's size and making better use of space for the position detection mechanism. However, this still requires two PCB boards, and the wire connection between them carries the risk of disconnection, leading to poor reliability and stability. Furthermore, the brushless motor's housing still occupies a considerable amount of internal space, making further size reduction difficult. Therefore, an improvement is necessary. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a brushless servo motor that simplifies the structure, reduces costs, decreases size, and improves reliability and stability.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a brushless servo motor, comprising a housing and a brushless motor, a reduction gear set, an output shaft, and an output position detection component disposed within the housing. The brushless motor is driven by the reduction gear set, the reduction gear set is driven by the output shaft, and the output position detection component is connected to the output shaft. A motor mounting post is formed on the inner bottom surface of the housing, and a shaft hole is formed in the middle of the motor mounting post. The brushless motor includes an outer rotor housing, an outer rotor assembly, an inner stator assembly, and a shaft. The shaft is rotatably mounted in a shaft hole. The lower part of the outer rotor housing is open, and the upper part of the outer rotor housing is fixedly connected to the shaft. The outer rotor assembly is fixedly mounted on the inner side of the outer rotor housing, and the inner stator assembly is fixedly mounted on the outer side of the motor mounting post and located inside the outer rotor housing. A PCB board is provided at the bottom of the outer casing. The PCB board has a fixing hole at the position of the motor fixing post. The fixing hole is fitted onto the motor fixing post. The PCB board is located below the brushless motor. A motor position detection component for detecting the position of the outer rotor assembly is provided on the side of the PCB board facing the brushless motor. The motor position detection component is located below the outer rotor assembly. The output position detection component is fixedly installed on the PCB board and located next to the brushless motor. The PCB board is provided with a servo control circuit. The output position detection component, the inner stator assembly, and the motor position detection component are electrically connected to the servo control circuit.

[0006] In a further technical solution, the outer casing includes an upper cover, a middle cover, and a lower cover. The upper cover is located on the upper part of the middle cover, and the lower cover is located on the lower part of the middle cover. The middle cover has a motor mounting slot with an opening facing downward and an output mounting slot with an opening facing upward. The motor mounting slot and the output mounting slot are arranged side by side with intervals and relative separation. A transmission cavity is provided between the upper cover and the middle cover, and a control cavity is provided between the lower cover and the middle cover. The upper part of the output mounting slot communicates with the transmission cavity, and the lower part of the motor mounting slot communicates with the control cavity. A detection through hole is provided in the lower part of the output mounting slot, and a transmission through hole is provided in the upper part of the motor mounting slot. A reduction gear set is located in the transmission cavity. The output shaft is rotatably mounted in the output mounting slot. The PCB board is fixedly mounted on the lower cover. The output position detection component is located on the upper end face of the PCB board. The lower part of the output shaft passes through the detection through hole and connects to the output position detection component. The brushless motor is located in the motor mounting slot, and the upper end of the shaft passes through the transmission through hole and is connected to the reduction gear set for transmission.

[0007] In a further technical solution, the reduction gear set includes a first gear, a second gear, a third gear, and a fourth gear. The first gear is fixedly installed on the upper end of the shaft and located in the transmission cavity. The fourth gear is sleeved on the output shaft and located in the output mounting groove. The second gear and the third gear are rotatably installed in the transmission cavity and located between the first gear and the fourth gear. The first gear meshes with the second gear, the second gear meshes with the third gear, and the third gear meshes with the fourth gear.

[0008] In a further technical solution, the second gear and the third gear are double gears. The large gear of the second gear meshes with the first gear, the small gear of the second gear meshes with the large gear of the third gear, and the small gear of the third gear extends into the output mounting slot and meshes with the fourth gear.

[0009] In a further technical solution, an annular sealing mounting groove is provided on the outer side of the first gear along the circumferential direction, and a sealing ring is embedded in the sealing mounting groove, with the sealing ring located above the transmission through hole.

[0010] In a further technical solution, the output shaft is provided with a splined part, a transmission part, and a detection part from top to bottom. The outer side of the splined part is provided with multiple spline grooves. The splined part passes through the upper cover and is connected to the rudder. The outer side of the transmission part is provided with multiple clutch protrusions at intervals along the circumferential direction. A clutch groove is opened in the middle of the fourth gear. A through-rod hole is provided at the bottom of the clutch groove to pass through the fourth gear. The detection part passes through the through-rod hole and is connected to the output position detection component. The inner side of the clutch groove is provided with multiple clutch grooves at intervals along the circumferential direction, which correspond one-to-one with the clutch protrusions. The transmission part is embedded in the clutch groove, and each clutch protrusion is embedded in each clutch groove.

[0011] In a further technical solution, the lower part of the fourth gear is provided with a downward-facing limiting groove, the lower part of the output mounting groove is provided with an upward-protruding limiting protrusion, the limiting protrusion extends into the limiting groove, and the upper part of the limiting groove is provided with multiple heat dissipation grooves at intervals along the circumferential direction.

[0012] In a further technical solution, the motor fixing column is formed on the lower cover, the upper end of the shaft hole is connected to the motor mounting groove, the lower end of the shaft hole passes through the lower cover, the lower end of the shaft hole is sealed with a cover plate, two bearings are set between the shaft and the shaft hole, the two bearings are set at intervals, a retaining ring is snapped into the lower part of the shaft, and wear-resistant washers are set between the upper bearing and the outer rotor housing and between the lower bearing and the retaining ring, respectively. The upper part of the outer rotor housing has multiple heat dissipation holes that penetrate the outer rotor housing. Each heat dissipation hole is spaced apart along the circumferential direction and located on the periphery of the shaft.

[0013] In a further technical solution, the outer rotor assembly includes a magnetic yoke ring, multiple magnetic yoke teeth, and multiple permanent magnets. The magnetic yoke ring is fixedly installed on the inner surface of the outer rotor housing. Each magnetic yoke tooth is formed on the lower end face of the magnetic yoke ring, and a spacer groove is formed between two adjacent magnetic yoke teeth. Each permanent magnet is embedded in the spacer groove. The inner stator assembly includes a stator core and a coil winding wound around the stator core. The stator core is fitted onto the motor mounting post. The stator core has multiple winding slots spaced along the circumferential direction to accommodate the coil windings. A wire routing slot is vertically opened on the outer side of the motor mounting post. The end of the coil winding passes through the wire routing slot and is connected to the PCB board and electrically connected to the servo control circuit. The motor position detection component includes at least two Hall sensors, which are respectively disposed on the upper surface of the PCB board and located below each permanent magnet. The two Hall sensors respectively cooperate with the Hall sensing of each permanent magnet. The output position detection component includes a potentiometer, which is located on the upper surface of the PCB board and electrically connected to the servo control circuit. A connection socket is provided on each side of the PCB board, and the two connection sockets are electrically connected to the servo control circuit.

[0014] In a further technical solution, a virtual rudder assembly is provided at the lower part of the lower cover corresponding to the position of the output shaft. The virtual rudder assembly includes a virtual rudder and a flange. A downward-facing virtual rudder groove is provided at the lower part of the lower cover. A mounting boss is provided in the virtual rudder groove. A mounting groove corresponding to the mounting boss is provided on the upper end face of the flange. The flange is embedded in the virtual rudder groove, and the mounting boss is inserted into the mounting groove. The virtual rudder is fixedly installed on the flange.

[0015] The advantages of this invention compared to existing technologies are as follows: By forming a motor fixing post and opening a shaft hole on the bottom surface of the outer casing, the brushless motor is directly integrated into the casing structure to form an integral structure, eliminating the need for a stator casing, simplifying the structure, reducing costs, and reducing axial space, thus decreasing the overall thickness of the brushless servo; the lower opening of the outer rotor casing allows the motor position detection component to be integrated onto the PCB board below, enabling axial space reuse between the brushless motor and the motor position detection component, making full use of the installation space, and further reducing the size of the brushless servo; both the motor position detection component and the output position detection component are mounted on the same PCB board, requiring only one PCB board for the brushless servo, eliminating the need for wire connections, reducing the risk of disconnection, enhancing shock resistance, and improving reliability and stability. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is an exploded view of the present invention; Figure 3 This is a cross-sectional view of the present invention; Figure 4 This is an exploded view of the brushless motor of this utility model; Figure 5 This is an exploded view of the output shaft and the fourth gear of this utility model; Figure 6 This is a schematic diagram of the bottom structure of the fourth gear of this utility model.

[0018] In the picture: 11 Top cover, 12 Middle shell, 121 Motor mounting slot, 122 Transmission through hole, 123 Output mounting slot, 124 Detection through hole, 125 Limiting protrusion, 13 Bottom cover, 131 Motor fixing post, 132 Shaft hole, 133 Wiring groove, 134 Virtual rudder groove, 135 Mounting boss, 14 Transmission cavity, 15 Control cavity, 16 Cover plate; 2. Brushless motor, 21. Outer rotor housing, 211. Heat dissipation hole, 22. Outer rotor assembly, 221. Magnetic yoke ring, 222. Magnetic yoke tooth, 223. Permanent magnet, 224. Spacing slot, 23. Stator core, 231. Winding slot, 24. Shaft, 25. Bearing, 26. Snap ring, 27. Wear-resistant washer. 3. Reduction gear set, 31. First gear, 311. Sealing ring, 32. Second gear, 33. Third gear, 34. Fourth gear, 341. Clutch groove, 342. Through rod hole, 343. Clutch groove, 344. Limiting groove, 345. Heat dissipation groove; 4 Output shaft, 41 Splined part, 42 Transmission part, 43 Detection part, 44 Clutch protrusion; 5 PCB boards, 51 connector sockets; 6 potentiometers; 7 Hall effect sensors; 8 steering wheels; 91 Virtual rudder disc, 92 Flange, 93 Mounting groove. Detailed Implementation

[0019] The following are merely preferred embodiments of the present invention and do not limit the scope of protection of the present invention.

[0020] A type of brushless servo, such as Figures 1 to 6 As shown, the device includes a housing and a brushless motor 2, a reduction gear set 3, an output shaft 4, and an output position detection component housed within the housing. The brushless motor 2 is driven by the reduction gear set 3, which is driven by the output shaft 4. The output position detection component is connected to the output shaft 4. A motor mounting post 131 is formed on the inner bottom surface of the housing, and a shaft hole 132 is formed in the middle of the motor mounting post 131. The brushless motor 2 includes an outer rotor housing 21, an outer rotor assembly 22, an inner stator assembly, and a shaft 24. The shaft 24 is rotatably mounted in the shaft hole 132. The lower part of the outer rotor housing 21 is open, and the upper part of the outer rotor housing 21 is fixedly connected to the shaft 24. The outer rotor assembly 22 is fixedly mounted on the inner side of the outer rotor housing 21, and the inner stator assembly is fixed. The PCB board 5 is installed on the outer side of the motor mounting post 131 and inside the outer rotor housing 21. The lower part of the housing is provided with a PCB board 5. The PCB board 5 has a fixing through hole corresponding to the position of the motor mounting post 131. The fixing through hole is fitted onto the motor mounting post 131. The PCB board 5 is located below the brushless motor 2. A motor position detection component for detecting the position of the outer rotor assembly 22 is provided on the side of the PCB board 5 facing the brushless motor 2. The motor position detection component is located below the outer rotor assembly 22. The output position detection component is fixedly installed on the PCB board 5 and located next to the brushless motor 2. The PCB board 5 is provided with a servo control circuit. The output position detection component, the inner stator assembly and the motor position detection component are electrically connected to the servo control circuit.

[0021] Traditional brushless servos have a separate brushless motor 2, which needs to be connected to the PCB board 5 by soldering or wires. Furthermore, the position detection mechanism of the brushless motor 2 is usually built into the brushless motor 2, resulting in a large overall size of the brushless motor 2 and consequently, a larger brushless servo. Some designs place the position detection mechanism separately on the outside of the brushless motor 2, requiring at least two PCB boards 5 inside the brushless servo. To ensure communication, the two PCB boards 5 need to be connected with wires, resulting in a complex structure, high cost, and poor shock resistance. This invention, however, by forming a motor fixing post 131 on the bottom surface of the inner shell and opening a shaft hole 132, integrates the brushless motor... The brush motor 2 is directly integrated into the housing structure to form a one-piece structure, eliminating the need for a stator housing, simplifying the structure, reducing costs, and reducing axial space, thus decreasing the overall thickness of the brushless servo. The lower opening of the outer rotor housing 21 integrates the motor position detection component onto the lower PCB board 5, enabling axial space reuse between the brushless motor 2 and the motor position detection component, making full use of installation space and further reducing the size of the brushless servo. Both the motor position detection component and the output position detection component are set on the same PCB board 5, with only one PCB board 5 for the brushless servo, eliminating the need for wire connections, reducing the risk of disconnection, enhancing shock resistance, and improving reliability and stability.

[0022] Specifically, the outer casing includes an upper cover 11, a middle cover 12, and a lower cover 13. The upper cover 11 is located on the upper part of the middle cover 12, and the lower cover 13 is located on the lower part of the middle cover 12. The middle cover 12 has a downward-facing motor mounting slot 121 and an upward-facing output mounting slot 123. The motor mounting slot 121 and the output mounting slot 123 are arranged side by side with intervals and relative to each other. A transmission cavity 14 is provided between the upper cover 11 and the middle cover 12, and a control cavity 15 is provided between the lower cover 13 and the middle cover 12. The upper part of the output mounting slot 123 communicates with the transmission cavity 14, and the lower part of the motor mounting slot 121 communicates with the control cavity. 15. The lower part of the output mounting slot 123 is provided with a detection through hole 124, the upper part of the motor mounting slot 121 is provided with a transmission through hole 122, the reduction gear set 3 is provided in the transmission cavity 14, the output shaft 4 is rotatably mounted in the output mounting slot 123, the PCB board 5 is fixedly mounted on the lower cover 13, the output position detection component is provided on the upper end face of the PCB board 5, the lower part of the output shaft 4 passes through the detection through hole 124 and is connected to the output position detection component, the brushless motor 2 is provided in the motor mounting slot 121, and the upper end of the shaft 24 passes through the transmission through hole 122 and is connected to the reduction gear set 3 for transmission.

[0023] The outer casing is divided into three parts: an upper cover 11, a middle cover 12, and a lower cover 13. These parts are connected and fixed with screws for easy assembly and maintenance. Removing the upper cover 11 exposes the transmission cavity 14, facilitating the repair of the reduction gear set 3. Removing the lower cover 13 exposes the control cavity 15, facilitating the repair of the brushless motor 2, PCB board 5, and output position detection component. This eliminates the need for complete disassembly, improving maintenance efficiency. After installing the brushless motor 2 and output shaft 4, the control cavity 15 is relatively isolated from the transmission cavity 14, preventing gear lubricating oil from the transmission cavity 14 from entering the control cavity 15 and contaminating the brushless motor 2, PCB board 5, and output position detection component, thus improving reliability and stability and reducing the failure rate. The space of the transmission cavity 14 is expanded by the output mounting slot 123, and the space of the control cavity 15 is expanded by the motor mounting slot 121, maximizing the space of both cavities and forming two independent heat dissipation spaces to improve heat dissipation.

[0024] Specifically, the reduction gear set 3 includes a first gear 31, a second gear 32, a third gear 33, and a fourth gear 34. The first gear 31 is fixedly mounted on the upper end of the shaft 24 and located within the transmission cavity 14. The fourth gear 34 is sleeved on the output shaft 4 and located within the output mounting groove 123. The second gear 32 and the third gear 33 are rotatably mounted within the transmission cavity 14 and located between the first gear 31 and the fourth gear 34. The first gear 31 meshes with the second gear 32, the second gear 32 meshes with the third gear 33, and the third gear 33 meshes with the fourth gear 34. The reduction gear set 3 adopts a three-stage reduction meshing transmission, which increases torque while reducing the number of gears, thereby reducing installation space and shrinking the size of the brushless servo. The gear module decreases in a stepwise manner, resulting in uniform stress distribution on the meshing contact surface and improving transmission efficiency.

[0025] Specifically, the second gear 32 and the third gear 33 are double gears. The large gear of the second gear 32 meshes with the first gear 31, and the small gear of the second gear 32 meshes with the large gear of the third gear 33. The small gear of the third gear 33 extends into the output mounting slot 123 and meshes with the fourth gear 34.

[0026] The fourth gear 34 is housed within the output mounting slot 123. The fourth gear 34 and the output shaft 4 are arranged side-by-side with the brushless motor 2, forming a symmetrical left-right structure. Meanwhile, the reduction gear set 3, the PCB board 5, and the output position detection assembly form a symmetrical top-bottom structure. This arrangement fully utilizes the installation space, further reducing the size of the brushless servo and centering its center of gravity, thus meeting the requirements for high-level installations. The double gear arrangement further reduces axial space requirements.

[0027] Specifically, the outer surface of the first gear 31 is provided with an annular sealing mounting groove along the circumferential direction, and a sealing ring 311 is embedded in the sealing mounting groove. The sealing ring 311 is located above the transmission through hole 122. The sealing ring 311 prevents the gear lubricating oil in the transmission cavity 14 from entering the motor mounting groove 121 through the transmission through hole 122, thus avoiding contamination of the motor mounting groove 121 and the control cavity 15, improving reliability and stability. At the same time, it can also reduce the evaporation of gear lubricating oil, extend the maintenance cycle, and reduce the operating cost and failure rate.

[0028] Specifically, the output shaft 4 is provided with a splined part 41, a transmission part 42, and a detection part 43 from top to bottom. The outer side of the splined part 41 is provided with multiple spline grooves. The splined part 41 passes through the upper cover 11 and is connected to the rudder disk 8. The outer side of the transmission part 42 is provided with multiple clutch protrusions 44 at intervals along the circumferential direction. The fourth gear 34 has a clutch groove 341 in the middle. The bottom of the clutch groove 341 is provided with a through hole 342 that passes through the fourth gear 34. The detection part 43 passes through the through hole 342 and is connected to the output position detection component. The inner side of the clutch groove 341 is provided with multiple clutch grooves 343 at intervals along the circumferential direction that correspond one-to-one with the clutch protrusions 44. The transmission part 42 is embedded in the clutch groove 341, and each clutch protrusion 44 is embedded in each clutch groove 343. When the load torque is too high, the originally meshing clutch protrusion 44 and clutch groove 343 automatically disengage, thereby protecting the brushless motor 2 and the reduction gear set 3, preventing gear breakage, reducing the load on the brushless motor 2, and extending its service life; the spline part 41 is connected to the rudder disk 8 through the spline groove, which improves the connection strength, prevents the generation of play, and improves the control accuracy; the output shaft 4 is directly connected to the output position detection component through the detection part 43, eliminating the accumulated error of traditional indirect transmission and improving the position repeatability accuracy.

[0029] Specifically, the lower part of the fourth gear 34 is provided with a downward-facing limiting groove 344, the lower part of the output mounting groove 123 is provided with an upward-protruding limiting protrusion 125, the limiting protrusion 125 extends into the limiting groove 344, and the upper part of the limiting groove 344 is provided with a plurality of heat dissipation grooves 345 at intervals along the circumferential direction.

[0030] Since the output shaft 4 and the fourth gear 34 have relatively large diameters, their weight is relatively increased. By using the limiting protrusion 125 and the limiting groove 344 to cooperate, the axial movement of the gear is reduced and the transmission backlash is reduced. While the fourth gear 34 is rotating, the airflow is guided by the heat dissipation groove 345 to blow on the surface of the fourth gear 34, thereby improving the heat dissipation effect and reducing the weight of the fourth gear 34, thus reducing the load on the brushless motor 2.

[0031] Specifically, the motor fixing post 131 is formed on the lower cover 13, the upper end of the shaft hole 132 is connected to the motor mounting groove 121, the lower end of the shaft hole 132 passes through the lower cover 13, and the lower end of the shaft hole 132 is sealed with a cover plate 16. Two bearings 25 are provided between the shaft 24 and the shaft hole 132, and the two bearings 25 are arranged vertically and horizontally. A retaining ring 26 is snapped into the lower part of the shaft 24. Wear-resistant washers 27 are respectively provided between the upper bearing 25 and the outer rotor housing 21 and between the lower bearing 25 and the retaining ring 26. Multiple heat dissipation holes 211 are opened on the upper part of the outer rotor housing 21, and each heat dissipation hole 211 is arranged at intervals along the circumferential direction and located on the periphery of the shaft 24. Two bearings 25 reduce the rotational friction of the shaft 24 and simultaneously reduce the axial composite load, thereby reducing the radial runout of the shaft 24 and making the operation more stable. Two wear-resistant washers 27 prevent the shaft 24 from rotating and wearing during axial runout, thus improving its service life. During assembly and maintenance, the retaining ring 26 can be disassembled and assembled by opening the cover plate 16, thereby enabling the disassembly and assembly of the shaft 24. The cover plate 16 not only hides the shaft 24 but also seals the shaft hole 132, preventing foreign objects from entering and improving waterproofing.

[0032] Specifically, the outer rotor assembly 22 includes a magnetic yoke ring 221, multiple magnetic yoke teeth 222, and multiple permanent magnets 223. The magnetic yoke ring 221 is fixedly installed on the inner surface of the outer rotor housing 21. Each magnetic yoke tooth 222 is formed on the lower end face of the magnetic yoke ring 221, and a spacer slot 224 is formed between two adjacent magnetic yoke teeth 222. Each permanent magnet 223 is embedded in the spacer slot 224. The inner stator assembly includes a stator core 23 and a coil winding wound around the stator core 23. The stator core 23 is sleeved on the motor mounting post 131. The stator core 23 has multiple winding slots 231 spaced along the circumferential direction for accommodating the coil winding. The outer side of the motor mounting post 131... A vertical wiring groove 133 is provided on the surface of the PCB board 5. The end of the coil winding passes through the wiring groove 133 and is connected to the PCB board 5 and electrically connected to the servo control circuit. The motor position detection component includes at least two Hall sensors 7, which are respectively located on the upper surface of the PCB board 5 and below each permanent magnet 223. The two Hall sensors 7 are respectively Hall sensing-coordinated with each permanent magnet 223. The output position detection component includes a potentiometer 6, which is located on the upper surface of the PCB board 5 and electrically connected to the servo control circuit. A connection socket 51 is provided on each side of the PCB board 5, and the two connection sockets 51 are respectively electrically connected to the servo control circuit. The coil winding is routed downward through the winding groove 231 and connected to the PCB board 5. The winding groove 231 can avoid squeezing the coil winding, prevent breakage, and improve reliability and stability. The Hall sensor 223 directly and vertically detects the magnetic field change of the permanent magnet 223 with an angular resolution of 0.01°, improving detection accuracy. The heat generated by the external rotor brushless motor 2 is concentrated on the stator assembly. The stator assembly directly conducts the heat to the housing of the brushless servo motor through the motor mounting post 131, thereby improving the heat dissipation efficiency.

[0033] Specifically, a virtual rudder assembly is provided at the lower part of the lower cover 13 corresponding to the position of the output shaft 4. The virtual rudder assembly includes a virtual rudder 91 and a flange 92. A downward-facing virtual rudder groove 134 is provided at the lower part of the lower cover 13, and a mounting boss 135 is provided in the virtual rudder groove 134. The upper end face of the flange 92 is provided with a mounting groove 93 corresponding to the mounting boss 135. The flange 92 is embedded in the virtual rudder groove 134, and the mounting boss 135 is inserted into the mounting groove 93. The virtual rudder 91 is fixedly installed on the flange 92. The virtual rudder 91 is mechanically zero-point blind-fit positioning, which shortens the calibration time and is suitable for batch debugging on the production line. The concave-convex structure restricts the virtual rudder 91 to installation in only one direction, reducing the assembly error rate.

[0034] The above description is only a preferred embodiment of this utility model. For those skilled in the art, there will be changes in the specific implementation method and application scope based on the idea of ​​this utility model. The content of this specification should not be construed as a limitation of this utility model.

Claims

1. A brushless servo motor, comprising a housing and a brushless motor (2), a reduction gear set (3), an output shaft (4), and an output position detection component disposed within the housing, wherein the brushless motor (2) is drivenly connected to the reduction gear set (3), the reduction gear set (3) is drivenly connected to the output shaft (4), and the output position detection component is connected to the output shaft (4), characterized in that: The inner bottom surface of the outer casing is formed with a motor fixing post (131), and a shaft hole (132) is opened in the middle of the motor fixing post (131). The brushless motor (2) includes an outer rotor housing (21), an outer rotor assembly (22), an inner stator assembly, and a shaft (24). The shaft (24) is rotatably mounted in a shaft hole (132). The lower part of the outer rotor housing (21) is open, and the upper part of the outer rotor housing (21) is fixedly connected to the shaft (24). The outer rotor assembly (22) is fixedly mounted on the inner side of the outer rotor housing (21), and the inner stator assembly is fixedly mounted on the outer side of the motor mounting post (131) and located inside the outer rotor housing (21). A PCB board (5) is provided at the lower part of the outer casing. A fixing hole is provided on the PCB board (5) corresponding to the position of the motor fixing post (131). The fixing hole is fitted onto the motor fixing post (131). The PCB board (5) is located below the brushless motor (2). A motor position detection component for detecting the position of the outer rotor assembly (22) is provided on the side of the PCB board (5) facing the brushless motor (2). The motor position detection component is located below the outer rotor assembly (22). The output position detection component is fixedly installed on the PCB board (5) and located next to the brushless motor (2). The PCB board (5) is provided with a servo control circuit. The output position detection component, the inner stator assembly and the motor position detection component are electrically connected to the servo control circuit respectively.

2. The brushless servo motor according to claim 1, characterized in that: The outer casing includes an upper cover (11), a middle shell (12), and a lower cover (13). The upper cover (11) is located on the upper part of the middle shell (12), and the lower cover (13) is located on the lower part of the middle shell (12). The middle shell (12) has a downward-facing motor mounting slot (121) and an upward-facing output mounting slot (123). The motor mounting slot (121) and the output mounting slot (123) are arranged side by side with intervals and relative separation. The upper cover (11) has a transmission cavity (14) between it and the middle shell (12), and the lower cover (13) has a control cavity (15) between it and the middle shell (12). The upper part of the output mounting slot (123) is connected to the transmission cavity (14), and the lower part of the motor mounting slot (121) is connected to the control cavity (15). The lower part of the output mounting slot (123) is provided with a detection through hole (124), the upper part of the motor mounting slot (121) is provided with a transmission through hole (122), the reduction gear set (3) is provided in the transmission cavity (14), the output shaft (4) is rotatably mounted in the output mounting slot (123), the PCB board (5) is fixedly mounted on the lower cover (13), the output position detection component is provided on the upper end face of the PCB board (5), the lower part of the output shaft (4) passes through the detection through hole (124) and is connected to the output position detection component, the brushless motor (2) is provided in the motor mounting slot (121), and the upper end of the shaft (24) passes through the transmission through hole (122) and is connected to the reduction gear set (3) for transmission.

3. A brushless servo motor according to claim 2, characterized in that: The reduction gear set (3) includes a first gear (31), a second gear (32), a third gear (33) and a fourth gear (34). The first gear (31) is fixedly installed on the upper end of the shaft (24) and located in the transmission cavity (14). The fourth gear (34) is sleeved on the output shaft (4) and located in the output mounting groove (123). The second gear (32) and the third gear (33) are rotatably installed in the transmission cavity (14) and located between the first gear (31) and the fourth gear (34). The first gear (31) meshes with the second gear (32), the second gear (32) meshes with the third gear (33), and the third gear (33) meshes with the fourth gear (34).

4. A brushless servo motor according to claim 3, characterized in that: The second gear (32) and the third gear (33) are double gears. The large gear of the second gear (32) meshes with the first gear (31), and the small gear of the second gear (32) meshes with the large gear of the third gear (33). The small gear of the third gear (33) extends into the output mounting slot (123) and meshes with the fourth gear (34).

5. A brushless servo motor according to claim 3, characterized in that: The outer side of the first gear (31) is provided with an annular sealing mounting groove along the circumferential direction, and a sealing ring (311) is embedded in the sealing mounting groove. The sealing ring (311) is located above the transmission through hole (122).

6. A brushless servo motor according to claim 3, characterized in that: The output shaft (4) is provided with a splined part (41), a transmission part (42) and a detection part (43) from top to bottom. The outer side of the splined part (41) is provided with multiple spline grooves. The splined part (41) passes through the upper cover (11) and is connected to the rudder disk (8). The outer side of the transmission part (42) is provided with multiple clutch protrusions (44) at intervals along the circumferential direction. The fourth gear (34) has a clutch groove (341) in the middle. The bottom of the groove is provided with a through hole (342) for the fourth gear (34). The detection part (43) passes through the through hole (342) and is connected to the output position detection component. The inner side of the clutch groove (341) is provided with a plurality of clutch grooves (343) that correspond one-to-one with the clutch protrusions (44) along the circumferential direction. The transmission part (42) is embedded in the clutch groove (341), and each clutch protrusion (44) is embedded in each clutch groove (343).

7. A brushless servo motor according to claim 6, characterized in that: The lower part of the fourth gear (34) is provided with a downward-facing limiting groove (344), and the lower part of the output mounting groove (123) is provided with an upward-protruding limiting protrusion (125). The limiting protrusion (125) extends into the limiting groove (344), and the upper part of the limiting groove (344) is provided with multiple heat dissipation grooves (345) spaced apart along the circumferential direction.

8. A brushless servo motor according to claim 2, characterized in that: The motor fixing column (131) is formed on the lower cover (13). The upper end of the shaft hole (132) is connected to the motor mounting groove (121). The lower end of the shaft hole (132) passes through the lower cover (13). The lower end of the shaft hole (132) is sealed with a cover plate (16). Two bearings (25) are provided between the shaft (24) and the shaft hole (132). The two bearings (25) are arranged at intervals. A retaining ring (26) is snapped into the lower part of the shaft (24). Wear-resistant washers (27) are respectively provided between the upper bearing (25) and the outer rotor housing (21) and between the lower bearing (25) and the retaining ring (26). The upper part of the outer rotor housing (21) is provided with a plurality of heat dissipation holes (211) that penetrate the outer rotor housing (21). Each heat dissipation hole (211) is spaced apart along the circumferential direction and located on the periphery of the shaft (24).

9. A brushless servo motor according to claim 2, characterized in that: The outer rotor assembly (22) includes a magnetic yoke ring (221), multiple magnetic yoke protrusions (222), and multiple permanent magnets (223). The magnetic yoke ring (221) is fixedly installed on the inner surface of the outer rotor housing (21). Each magnetic yoke protrusion (222) is formed on the lower end face of the magnetic yoke ring (221). A spacer groove (224) is formed between two adjacent magnetic yoke protrusions (222). Each permanent magnet (223) is embedded in the spacer groove (224). The inner stator assembly includes a stator core (23) and a coil winding wound around the stator core (23). The stator core (23) is sleeved on the motor mounting post (131). The stator core (23) is provided with a plurality of winding slots (231) for accommodating the coil winding at intervals along the circumferential direction. The outer side of the motor mounting post (131) is provided with a vertical wiring slot (133). The end of the coil winding passes through the wiring slot (133) and is connected to the PCB board (5) and electrically connected to the servo control circuit. The motor position detection component includes at least two Hall sensors (7). The two Hall sensors (7) are respectively disposed on the upper surface of the PCB board (5) and located below each permanent magnet (223). The two Hall sensors (7) are respectively Hall sensing-coordinated with each permanent magnet (223). The output position detection component includes a potentiometer (6), which is disposed on the upper surface of the PCB board (5) and electrically connected to the servo control circuit. A connection socket (51) is provided on each side of the PCB board (5), and the two connection sockets (51) are electrically connected to the servo control circuit respectively.

10. A brushless servo motor according to claim 9, characterized in that: The lower part of the lower cover (13) is provided with a virtual rudder assembly corresponding to the position of the output shaft (4). The virtual rudder assembly includes a virtual rudder (91) and a flange (92). The lower part of the lower cover (13) is provided with a virtual rudder groove (134) with the opening facing downward. A mounting boss (135) is provided in the virtual rudder groove (134). The upper end face of the flange (92) is provided with a mounting groove (93) corresponding to the mounting boss (135). The flange (92) is embedded in the virtual rudder groove (134), and the mounting boss (135) is inserted into the mounting groove (93). The virtual rudder (91) is fixedly installed on the flange (92).

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