CN215990401U

CN215990401U - High-speed cantilever type wheel hub motor of mobile platform

Info

Publication number: CN215990401U
Application number: CN202122460382.4U
Authority: CN
Inventors: 温群峰
Original assignee: Suzhou Shengyi Motor Co ltd
Current assignee: Suzhou Shengyi Motor Co ltd
Priority date: 2021-10-13
Filing date: 2021-10-13
Publication date: 2022-03-08
Anticipated expiration: 2031-10-13

Abstract

The utility model discloses a high-speed cantilever type wheel hub motor of a mobile platform, which comprises a wheel hub shell taking a cantilever shaft as a rotating axis, and a machine core shell, a machine core and a planetary speed reducing mechanism which are arranged in the wheel hub shell, wherein the machine core shell is fixed at the front end of the cantilever shaft; the front end of the front shaft shoulder is propped against the inner wall of the front end of the machine core shell through the front shaft bearing, the rear end of the rear shaft shoulder is propped against the rear shaft bearing, an axial gap is reserved between the rear end of the mandrel and the inner wall of the rear end of the machine core shell, and a wave pad is arranged between the rear shaft bearing and the inner wall of the rear end of the machine core shell. The utility model can reduce the axial force on the mandrel and the mandrel bearing, slow down the loss of the mandrel and the mandrel bearing and improve the working reliability of the hub motor.

Description

High-speed cantilever type wheel hub motor of mobile platform

Technical Field

The utility model relates to a high-speed cantilever type hub motor of a mobile platform.

Background

In the prior art, a mobile platform is flexible and stable in movement and high in steering precision, so that the mobile platform is widely applied to various fields of industry and life, for example, enterprise production workshops with high automation degree are generally provided with the mobile platform to convey production materials and products or carry service robots to perform production operation; golf courses, for example, are often equipped with golf carts or the like having a moving platform as a walking mechanism.

At present, the core driving part of the mobile platform is hub motors on two sides and is mostly a cantilever type hub motor. The main structure of such a cantilever type in-wheel motor generally includes a cantilever shaft, a hub shell, a movement, and a planetary reduction mechanism. The front end of the cantilever shaft is fixed with the machine core shell, the front end of the machine core shell is fixed with the support, and two ends of the wheel hub shell are respectively assembled on the cantilever shaft and the support through the wheel hub bearing. The core is located in the core shell and comprises a stator, a rotor and a core shaft fixed with the rotor, the core shaft and the cantilever shaft are coaxially arranged, the front end of the core shaft extends out of the core shell and is provided with shaft teeth meshed with a planetary gear in the planetary speed reducing mechanism, and the planetary gear is meshed with an inner gear ring on the hub shell so as to transmit power and drive the hub shell to rotate. It can be said that the structural characteristics of the existing cantilever-type hub motor determine the performance of the mobile platform. And along with the development of the mobile platform to the direction of high speed and heavy load, higher design requirements are provided for the structural characteristics of the cantilever type hub motor.

At present, due to the requirements of high speed and heavy load, and design considerations in the aspects of motion stability and noise reduction, the shaft teeth of the spindle of the known cantilever type hub motor are usually meshed with the planetary gear by adopting helical teeth, so that a better effect is achieved, but the following problems are also exposed in practical application:

the meshing structure of skewed tooth can make the dabber receive axial force and produce axial skew, but current cantilever type in-wheel motor, its dabber contacts with the dabber bearing through the shaft shoulder on it when designing, and then accomplish axial spacing and locking with the assembly between the bearing recess on the core case again, this when just causing the high-speed operation of motor, dabber and dabber bearing to and can all produce great axial extrusion force between dabber bearing and the core case, this can accelerate the wearing and tearing of dabber and dabber bearing in the past, and then cause the internal mechanism of motor moving unstability, and the noise production, cause whole motor to scrap even when serious.

Especially, most of the current moving platform hub motors are forward and reverse rotating motors, the forward rotation and the reverse rotation further enable the spindle to be subjected to axial forces in two directions, and the two axial forces are different in size, so that the stress deviation on the spindle is further amplified. As a result, the extrusion force on the spindle and the spindle bearing thereon is more frequent and larger, which makes the component loss more serious and the service life lower, and greatly reduces the operational reliability and stability of the cantilever type in-wheel motor, so that improvement is urgently needed.

Disclosure of Invention

The utility model aims to: the utility model provides a high-speed cantilever type in-wheel motor of moving platform, it can reduce and cushion the axial force that inside dabber and dabber bearing received when high-speed operation, slows down their loss to further improve the operational reliability and the stability of in-wheel motor internal mechanism, improve in-wheel motor life.

The technical scheme of the utility model is as follows: a high-speed cantilever type wheel hub motor of a mobile platform comprises a wheel hub shell taking a cantilever shaft as a rotating axis, a machine core shell, a machine core and a planetary reduction mechanism, wherein the machine core shell is arranged in the wheel hub shell; the core shaft is characterized in that the core shaft is supported and assembled in the core shell through a front core shaft bearing and a rear core shaft bearing together, a front shaft shoulder and a rear shaft shoulder are formed on the core shaft, the front end of the front shaft shoulder is abutted against the inner wall of the front end of the core shell through the front core shaft bearing, the rear end of the rear shaft shoulder is abutted against the rear core shaft bearing, an axial gap is reserved between the rear end of the core shaft and the inner wall of the rear end of the core shell, and a wave pad is padded between the rear core shaft bearing and the inner wall of the rear end of the core shell.

Further, a flat pad is padded between the wave pad and the rear mandrel bearing.

Furthermore, the planetary reduction mechanism also comprises a planetary support fixed at the front part of the machine core shell, the planetary gear is assembled on a planetary shaft through a planetary bearing, and two ends of the planetary shaft are supported and assembled in assembly holes arranged on the planetary support and the outer wall of the front part of the machine core shell. And as in the known art, the number of the planetary gears in the planetary reduction mechanism is usually 3 or more and is distributed at equal angular intervals in the circumferential direction.

Furthermore, the planetary gear is a nylon gear, a steel sleeve is fixed on the inner ring of the nylon gear, the inner side of the steel sleeve is supported and assembled on the planetary shaft through two planetary bearings, and the two planetary bearings are tightly pressed to two ends of the steel sleeve. The nylon gear can the noise reduction, and steel bushing and both ends planet bearing compress tightly the design purpose further increase planetary gear's structural strength to ensure its better with the spindle tooth meshing transmission power on the dabber, accord with the high-speed heavily loaded demand of motor.

Furthermore, the front end of the planet carrier is formed with a front support shaft which is coaxial with the cantilever shaft, and two ends of the hub shell are respectively assembled on the front support shaft and the cantilever shaft through hub bearings.

Furthermore, the speed detection device is arranged on the inner side of the core shell, is an inductive encoder and comprises a code disc and an encoder induction coil matched with the code disc, the code disc is fixed on the core shaft and rotates along with the core shaft, and the encoder induction coil is fixed on the inner side of the core shell and is opposite to the code disc.

Still further, the encoder induction coil is a PCB electromagnetic coil, and the PCB electromagnetic coil is a ring coil formed by attaching and etching a copper foil on a PCB, which is a known technology. The utility model adopts the electromagnetic coil of the PCB board to further reduce the volume of the inductive encoder, and is convenient for fixing and installing the inductive encoder inside the machine core shell.

Furthermore, the cantilever shaft is internally provided with outgoing line holes communicated with the inside and the outside of the hub shell, the core shell is provided with wiring holes, and the outgoing lines of the encoder induction coil and the coil arranged on the stator are led out to the outside of the hub shell through the wiring holes and the outgoing line holes in sequence.

It should be noted that the inductive encoder itself adopted in the present invention is a conventional technology, and converts the steering angular displacement of the rotor into corresponding electrical pulses through the change of the inductance, and outputs the electrical pulses to the controller of the mobile platform as digital quantities, and the controller accurately obtains the rotation angle position of the rotor, so that the rotation direction of the mobile platform can be more accurately controlled in the differential steering control.

Furthermore, the machine core shell is formed by mutually buckling a machine core front cover and a machine core rear cover and fixing the front cover and the rear cover through screws, the machine core rear cover is fixed at the front end of the cantilever shaft, the machine core front cover is provided with a shaft hole for the mandrel to extend out, a front bearing recess for embedding a front mandrel bearing is formed on the inner wall of the machine core front cover around the shaft hole, and the front end of the front shaft shoulder of the mandrel is abutted against the inner end wall of the front bearing recess through the front mandrel bearing; and a rear bearing recess for embedding the rear mandrel bearing is formed on the inner wall of the rear cover of the machine core, and an axial gap is reserved between the rear end of the mandrel and the inner end wall of the rear bearing recess.

The utility model has the advantages that:

1) in the structural design of the hub motor, an axial gap is reserved between the rear end of the mandrel and the inner wall of the rear end of the machine core shell, so that the mandrel is free to shift in the axial direction, the mandrel is ensured to have space to generate small shifting movement when being subjected to axial force generated by meshing of helical teeth, and large extrusion and friction between the mandrel and the inner wall of the machine core shell are avoided, so that the loss of the mandrel is reduced. And because the wave pad is arranged between the rear mandrel bearing and the inner wall of the rear end of the machine core shell, the buffer is provided for the offset of the rear mandrel bearing, the extrusion influence of the machine core shell caused by axial force on the rear mandrel bearing is weakened, the loss of the rear mandrel bearing is reduced, the working reliability and the stability of an internal mechanism of the hub motor are further improved, and the integral service life of the hub motor is prolonged.

2) The planet gear is a nylon gear, a steel sleeve is fixed on the inner ring of the nylon gear, the inner side of the steel sleeve is supported and assembled on the planet shaft through two planet bearings, and the two planet bearings are tightly pressed to two ends of the steel sleeve. The nylon gear can the noise reduction, and steel bushing and both ends planet bearing compress tightly the design purpose further increase planetary gear's structural strength to ensure its better with the spindle tooth meshing transmission power on the dabber, accord with the high-speed heavily loaded demand of motor.

Drawings

The utility model is further described with reference to the following figures and examples:

FIG. 1 is a main sectional view of the structure of the present invention.

Wherein: 1. a cantilever shaft; 1a, leading-out wire holes; 2. a hub shell; 3. a machine core shell; 3a, a front cover of the movement; 3b, a rear cover of the machine core; 4. a stator; 5. a rotor; 6. a mandrel; 6a, a front shaft shoulder; 6b, a rear shaft shoulder; 7. shaft teeth; 8. a shaft hole; 9. a planetary gear; 10. an inner gear ring; 11. a front spindle bearing; 12. a rear spindle bearing; 13. a wave pad; 14. flattening the cushion; 15. a planet carrier; 15a, a front support shaft; 16. a planetary bearing; 17. a planet shaft; 18. steel jacket; 19. a hub bearing; 20. code disc; 21. an encoder induction coil; 22. a wiring hole; 23. a front bearing pocket; 24. a rear bearing pocket.

Detailed Description

Example (b): referring to fig. 1, there is shown an embodiment of the high-speed cantilever-type hub motor for a mobile platform according to the present invention, which is mainly applied to a golf cart.

Like the conventional technology, the hub motor comprises a hub shell 2 taking a cantilever shaft 1 as a rotating axis, a core shell 3 arranged inside the hub shell 2, a core and a planetary reduction mechanism, wherein the core shell 3 is fixed at the front end of the cantilever shaft 1, the core is of an outer stator 4 and inner rotor 5 structure, the stator 4 is fixed on the inner wall of the core shell 3, a core shaft 6 coaxially arranged with the cantilever shaft 1 is fixed at the center of the rotor 5, the front end of the core shaft 6 is provided with a shaft tooth 7 and extends out of a shaft hole 8 in the front of the core shell 3 to be meshed with a planetary gear 9 in the planetary reduction mechanism through helical teeth, and the planetary gear 9 is further meshed with an inner gear ring 10 arranged on the inner wall of the hub shell 2, so that the hub shell 2 is driven to rotate by transmitting power.

The core improvement of the utility model is that: the mandrel 6 is supported and assembled in the core shell 3 through a front mandrel bearing 11 and a rear mandrel bearing 12, a front shaft shoulder 6a and a rear shaft shoulder 6b are formed on the mandrel 6, the front end of the front shaft shoulder 6a is abutted to the inner wall of the front end of the core shell 3 through the front mandrel bearing 11, the rear end of the rear shaft shoulder 6b is abutted to the rear mandrel bearing 12, an axial gap is reserved between the rear end of the mandrel 6 and the inner wall of the rear end of the core shell 3, and a flat pad 14 and a wave pad 13 are sequentially padded between the rear mandrel bearing 12 and the inner wall of the rear end of the core shell 3. The rear part of the wave pad 13 is abutted against the inner wall of the rear end of the machine core shell 3, and the front part of the wave pad is abutted against the rear mandrel bearing 12 through the flat pad 14. The wave pad 13 is used for buffering the extrusion between the rear spindle bearing 12 and the inner wall of the rear end of the movement shell 3, and the flat pad 14 is used for adjusting the gap between the rear spindle bearing 12 and the wave pad 13, so that the rear spindle bearing 12 and the wave pad 13 are not too wide or are not dead against each other.

In the planetary reduction mechanism of the present embodiment, the number of the planetary gears 9 is three as in the conventional art, and the planetary gears 9 are arranged at equal angular intervals on the circumference (only one planetary gear 9 can be seen in the sectional view of fig. 1). And the planetary reduction mechanism specifically further includes a planetary carrier 15, and a planetary shaft 17 and a planetary bearing 16 that support and mount each planetary gear 9. As shown in fig. 1, a planet carrier 15 is fixed to the front portion of the movement housing 3, each planet gear 9 is fitted to a planet shaft 17 through a planet bearing 16, and both ends of the planet shaft 17 are supportingly fitted in fitting holes provided in the planet carrier 15 and the outer wall of the front portion of the movement housing 3.

In this embodiment, the planetary gear 9 is a nylon gear, a steel sleeve 18 is fixed on the inner ring of the nylon gear, the inner side of the steel sleeve 18 is supported and assembled on the planetary shaft 17 through two planetary bearings 16, and the two planetary bearings 16 are pressed to the two ends of the steel sleeve 18. The nylon gear can reduce noise, and the design purpose that steel bushing 18 and both ends planet bearing 16 compress tightly is to further increase the structural strength of planet gear 9 to ensure that it is better with the epaxial tooth 7 meshing transmission power on dabber 6, accord with the demand of the high-speed heavy load of motor.

In this embodiment, the front end of the planet carrier 15 is formed with a front support shaft 15a coaxial with the cantilever shaft 1, and both ends of the hub shell 2 are respectively assembled on the front support shaft 15a and the cantilever shaft 1 through a hub bearing 19, as shown in fig. 1.

Still as shown in fig. 1, in the present embodiment, a speed detection device is further disposed inside the movement housing 3, the speed detection device is an inductance encoder, and includes a code wheel 20 and an encoder induction coil 21 matched with the code wheel 20, the code wheel 20 is fixed on the spindle 6 and rotates with the spindle 6, and the encoder induction coil 21 is fixed inside the movement housing 3 and is opposite to the code wheel 20. And the encoder induction coil 21 is a PCB board electromagnetic coil. The PCB electromagnetic coil refers to a loop coil formed by attaching copper foil on a PCB and etching the copper foil, and is a known technology. The utility model adopts the electromagnetic coil of the PCB board to further reduce the volume of the inductive encoder, and is convenient for fixing and installing the inductive encoder inside the machine core shell 3. The inductance encoder is a conventional technology, the steering angular displacement of the rotor 5 is converted into corresponding electric pulses through the change of inductance, the electric pulses are output to a controller of the mobile platform in a digital quantity mode, the rotating angle position of the rotor is accurately obtained through the controller, and then the rotating direction of the mobile platform can be controlled more accurately in the differential steering control.

Referring to fig. 1 again, the cantilever shaft 1 is provided therein with an outgoing line hole 1a communicating the inside and outside of the hub shell 2, the core shell 3 is provided with a routing hole 22, and the outgoing lines of the coils provided on the encoder induction coil 21 and the stator 4 are led out to the outside of the hub shell 2 through the routing hole 22 and the outgoing line hole 1a in sequence.

As shown in fig. 1, in this embodiment, the movement housing 3 is formed by mutually fastening a movement front cover 3a and a movement rear cover 3b and fixing them by screws, the movement rear cover 3b is fixed at the front end of the cantilever shaft 1, the movement front cover 3a is provided with the shaft hole 8 for the spindle 6 to extend out, a front bearing recess 23 for embedding the front spindle bearing 11 is formed on the inner wall of the movement front cover 3a around the shaft hole 8, and the front end of the front shaft shoulder 6a of the spindle 6 abuts against the inner end wall of the front bearing recess 23 through the front spindle bearing 11; and a rear bearing recess 24 for embedding the rear mandrel bearing 12 is formed on the inner wall of the movement rear cover 3b, and the axial gap is reserved between the rear end of the mandrel 6 and the inner end wall of the rear bearing recess 24.

In the structural design of the hub motor, an axial gap is reserved between the rear end of the mandrel 6 and the inner wall of the rear end of the core shell 3, namely, the mandrel 6 is free to shift in the axial direction, so that the mandrel 6 can generate small shifting movement in space when being subjected to axial force generated by meshing of helical teeth, and large extrusion and friction between the mandrel 6 and the inner wall of the core shell 3 are avoided, and the loss of the mandrel 6 is reduced. And because the wave pad 13 is arranged between the rear mandrel bearing 12 and the inner wall of the rear end of the movement shell 3, the buffer is provided for the deviation of the rear mandrel bearing 12, the extrusion influence of the movement shell 3 on the rear mandrel bearing 12 caused by axial force is also weakened, the loss of the rear mandrel bearing 12 is reduced, the work reliability and the stability of the internal mechanism of the hub motor are further improved, and the integral service life of the hub motor is prolonged.

It should be understood that the above-mentioned embodiments are only illustrative of the technical concepts and features of the present invention, and are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the scope of the present invention. All modifications made according to the spirit of the main technical scheme of the utility model are covered in the protection scope of the utility model.

Claims

1. A high-speed cantilever type wheel hub motor of a mobile platform comprises a wheel hub shell (2) taking a cantilever shaft (1) as a rotating axis, a machine core shell (3) arranged in the wheel hub shell (2), a machine core and a planetary speed reducing mechanism, wherein the machine core shell (3) is fixed at the front end of the cantilever shaft (1), the machine core is of an inner rotor (5) structure of an outer stator (4), the stator (4) is fixed on the inner wall of the machine core shell (3), a mandrel (6) coaxially arranged with the cantilever shaft (1) is fixed at the center of the rotor (5), shaft teeth (7) are arranged at the front end of the mandrel (6), the shaft teeth extend out of a shaft hole (8) in the front of the machine core shell (3) and are meshed with planetary gears (9) in the planetary speed reducing mechanism through helical teeth, and the planetary gears (9) are meshed with an inner gear ring (10) arranged on the inner wall of the wheel hub shell (2); the novel core shaft is characterized in that a core shaft (6) is supported and assembled in a core housing (3) through a front core shaft bearing (11) and a rear core shaft bearing (12) together, a front shaft shoulder (6 a) and a rear shaft shoulder (6 b) are formed on the core shaft (6), the front end of the front shaft shoulder (6 a) is abutted to the inner wall of the front end of the core housing (3) through the front core shaft bearing (11), the rear end of the rear shaft shoulder (6 b) is abutted to the rear core shaft bearing (12), an axial gap is reserved between the rear end of the core shaft (6) and the inner wall of the rear end of the core housing (3), and a wave pad (13) is padded between the rear core shaft bearing (12) and the inner wall of the rear end of the core housing (3).

2. The moving platform high-speed cantilever type hub motor according to claim 1, wherein a flat pad (14) is further padded between the wave pad (13) and the rear spindle bearing (12).

3. The high-speed cantilever type hub motor of a mobile platform according to claim 1, wherein the planetary reduction mechanism further comprises a planetary carrier (15) fixed at the front part of the movement housing (3), the planetary gear (9) is assembled on a planetary shaft (17) through a planetary bearing (16), and two ends of the planetary shaft (17) are supported and assembled in assembling holes arranged on the planetary carrier (15) and the outer wall of the front part of the movement housing (3).

4. The moving platform high-speed cantilever type hub motor according to claim 3, characterized in that the planetary gear (9) is a nylon gear, the inner ring of which is fixed with a steel sleeve (18), while the inner side of the steel sleeve (18) is supported and assembled on the planetary shaft (17) through two planetary bearings (16), and the two planetary bearings (16) are pressed to the two ends of the steel sleeve (18).

5. The high-speed cantilever-type hub motor of claim 3, wherein the front end of the planet carrier (15) is formed with a front support shaft (15 a) coaxial with the cantilever shaft (1), and the two ends of the hub shell (2) are respectively assembled on the front support shaft (15 a) and the cantilever shaft (1) through hub bearings (19).

6. The high-speed cantilever type hub motor of claim 1, further comprising a speed detection device arranged inside the core housing (3), wherein the speed detection device is an inductive encoder and comprises a code disc (20) and an encoder induction coil (21) matched with the code disc (20), the code disc (20) is fixed on the mandrel (6) and rotates with the mandrel (6), and the encoder induction coil (21) is fixed inside the core housing (3) and is opposite to the code disc (20).

7. The mobile platform high speed cantilevered in-wheel motor of claim 6, wherein said encoder induction coil (21) is a PCB board electromagnetic coil.

8. The high-speed cantilever type wheel hub motor of claim 6, wherein the cantilever shaft (1) is internally provided with an outgoing line hole (1 a) communicating the inside and outside of the wheel hub shell (2), the core shell (3) is provided with a routing hole (22), and the outgoing lines of the coils arranged on the encoder induction coil (21) and the stator (4) are sequentially led out to the outside of the wheel hub shell (2) through the routing hole (22) and the outgoing line hole (1 a).

9. The high-speed cantilever type hub motor of the mobile platform according to claim 1, wherein the core housing (3) is formed by mutually buckling a core front cover (3 a) and a core rear cover (3 b) and fixing the same through screws, the core rear cover (3 b) is fixed at the front end of the cantilever shaft (1), the core front cover (3 a) is provided with the shaft hole (8) for the core shaft (6) to extend out, the inner wall of the core front cover (3 a) is formed with a front bearing recess (23) around the shaft hole (8) for embedding the front core shaft bearing (11), and the front end of the front shaft shoulder (6 a) of the core shaft (6) is abutted against the inner end wall of the front bearing recess (23) through the front core shaft bearing (11); and a rear bearing recess (24) for embedding the rear mandrel bearing (12) is formed on the inner wall of the inner core rear cover (3 b), and an axial gap is reserved between the rear end of the mandrel (6) and the inner end wall of the rear bearing recess (24).