Disc type axial motor

Abstract

The utility model relates to a disc type axial motor, comprising a rotor which comprises a rotor iron core and magnets which are respectively arranged on the front side surface and the rear side surface of the rotor iron core and are arranged along the circumferential direction of the rotor iron core; the stator comprises a stator iron core, a tooth part which is arranged on one side surface of the stator iron core and is arranged along the circumferential direction of the chassis, and a coil which is arranged on the tooth part; the two stators are arranged on the front side and the rear side of the rotor respectively, and the tooth parts face the rotor. According to the disc type axial motor provided by the utility model, through the stator-rotor-stator design, the magnetic field of the motor is optimized, the energy density is high, and the rated torque can reach 2.3 Nm in a motor with the diameter of 90mm. And the effects of reducing the size and increasing the energy density are achieved, and the market requirement of the robot is met.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, in particular to a disc-type axial motor. Background Art

[0002] Robot joint modules generally use direct drive, often using electric motors as their power source. The unique motion of robots requires motors with lightweight, compact size, and high torque, while also requiring high dynamic response and reliability. Axial flux motors, frameless torque motors, and coreless motors are common choices for motors in current robot joints. Axial flux motors are flatter, save space, and offer higher torque density and positioning accuracy. Their high speed stability, fast response, low vibration, and high efficiency give them advantages in robot joint modules. Currently, rotary joint actuators for humanoid robots, robot dogs, and other devices mostly use frameless torque motors, which suffer from low torque. When faced with strong external forces, they cannot instantly provide overload capacity. Utility Model Content

[0003] In order to solve the above problems, the present technical solution provides a disc-type axial motor.

[0004] To achieve the above purpose, the technical solution is as follows:

[0005] A disc-type axial motor, comprising

[0006] The rotor comprises a rotor core and magnets disposed on the front and rear sides of the rotor core and along the circumference of the rotor core;

[0007] The stator comprises a stator core, teeth provided on one side of the stator core and arranged along the circumference of the chassis, and coils provided on the teeth;

[0008] The two stators are respectively arranged at the front and rear sides of the rotor, and the teeth face the rotor.

[0009] In the disc-type axial motor as described above, the ratio of the magnet to the coil is 20:18.

[0010] In the disc-type axial motor as described above, the outer diameter of the stator core is 76±1 mm, and the inner diameter is 57±1 mm.

[0011] In the disc-type axial motor as described above, the stator further includes a yoke, and the maximum magnetic flux density range of the teeth and the yoke is 1.4T-1.5T.

[0012] In the disc-type axial motor as described above, the thickness of the magnet is 3.45±0.5 mm.

[0013] In the disc-type axial motor as described above, the air gap between the stator and the rotor is 0.5±0.1 mm.

[0014] In the disc-type axial motor as described above, the magnetic poles of the two corresponding magnets on the two stators are the same.

[0015] As described above, the disc-type axial motor has a maximum rotation speed of 2600 rpm and a frequency of 433.33 Hz.

[0016] In the disc-type axial motor as described above, the sum of the heights of the stator core and the teeth is 8 mm.

[0017] As described above, a disc-type axial motor, the rotor core includes a main body, positioning shoulders protruding on the front and rear sides of the main body, a boss provided at the center of the main body and protruding to one side, a through hole provided on the side of the boss, and an axial hole provided on the boss.

[0018] The beneficial effects of this application are:

[0019] This utility model provides a disc-type axial motor. Its stator-rotor-stator design optimizes the motor's magnetic field and provides high energy density. In a 90mm diameter motor, the rated torque can reach 2.3Nm. It can also withstand overloads, achieving the effects of reducing volume while increasing energy density, meeting the market demand for robots. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments.

[0021] Figure 1 It is a structural diagram of the utility model;

[0022] Figure 2 It is a schematic diagram of the structural decomposition of the present utility model.

[0023] Reference numerals: rotor 1 , rotor core 11 , magnet 12 , stator 2 , stator core 21 , tooth portion 22 , coil 23 , body 111 , positioning shoulder 112 , boss 113 , through hole 114 , shaft hole 115 . DETAILED DESCRIPTION

[0024] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0025] A disc-type axial motor, comprising

[0026] The rotor 1 comprises a rotor core 11 and magnets 12 respectively arranged on the front and rear sides of the rotor core and arranged along the circumference of the rotor core;

[0027] The stator 2 includes a stator core 21, teeth 22 provided on one side of the stator core and arranged along the circumference of the chassis, and coils 23 provided on the teeth;

[0028] The two stators are respectively arranged at the front and rear sides of the rotor, and the teeth face the rotor.

[0029] This utility model provides a disc-type axial motor. Its stator-rotor-stator design optimizes the motor's magnetic field and achieves high energy density. In a 90mm diameter motor, the rated torque can reach 2.3Nm. It is also overload-resistant, miniaturizing the motor while increasing energy density, meeting the market demands of robotics. In this embodiment, it can withstand a six-fold overload.

[0030] Furthermore, as a preferred embodiment of the present invention but not a limitation, the ratio of the magnet to the coil is 20:18. Brushless torque motors (including radial flux and axial flux motors) usually adopt a multi-pole and few-slot type, or called fractional slot concentrated winding, which will be beneficial to reducing the cogging torque. At the same time, its winding end length is short, the loss is low, and the single tooth is formed, which is suitable for automated production. For motors with an outer diameter of about 90 mm, the commonly used pole-slot combinations (i.e., the combination of magnets and coils) are 16 poles and 15 slots, 16 poles and 21 slots, 20 poles and 18 slots, and 20 poles and 24 slots. The characteristics of these four pole-slot ratio types are shown in Table 1.

[0031] Table 1 Characteristics of four types of pole-slot combination motors.

[0032]

[0033] In summary, the 16-pole, 15-slot and 16-pole, 21-slot motors have high unilateral magnetic pull and require very high machining precision. Therefore, these two pole-slot combinations were not selected for this design. Compared with the 20-pole, 24-slot motor, while the 20-pole, 18-slot motor has similar overall performance, it has a higher winding coefficient. The fewer slots make manufacturing easier, and the overall slot insulation ratio is smaller, resulting in a higher power density. Therefore, the 20-pole, 18-slot motor is more suitable.

[0034] In this embodiment, in order to reduce loss, improve efficiency and reduce heat generation, the stator material is preferably made of high-frequency low-loss silicon steel sheets. Therefore, this motor uses B20AHV1200 silicon steel sheets, which have a performance of B 1900 =1.55T, B 1.5 / 50 =2.14W.

[0035] Furthermore, as a preferred embodiment of the present invention but not a limitation, the outer diameter of the stator core is 76±1mm, and the inner diameter is 57±1mm. For motors with a shell size of 90mm, since the shell adopts a die-casting process, considering the difficulty of the process and the strength of the shell, as well as the need for sufficient wiring clearance between the motor shell and the stator, the outer diameter of the stator core is reduced to 76mm and the inner diameter is 57mm. In this way, the outer diameter of the stator of the disc motor is taken as 57mm. Taking into account the assembly process of the motor and the reasonable air gap magnetic density requirements, the air gap is selected as 0.5mm, and the stator core height is set to 8mm based on the reasonable magnetic load of the motor and the requirements of the magnet ratio.

[0036] Furthermore, as a preferred embodiment of this solution, but not a limitation, the stator also includes a yoke, and the maximum magnetic flux density of the teeth and yoke is in the range of 1.4T to 1.5T. Due to the high overload requirements unique to articulated motors, sufficient linearity of motor characteristics must be ensured during motor design. Therefore, the magnetic flux density values at various locations on the stator and rotor should not be too high. Combined with the properties of the selected silicon steel sheets, the maximum magnetic flux density of the stator teeth and yoke is between 1.4T and 1.5T.

[0037] Furthermore, as a preferred embodiment of this solution, but not a limitation, the magnet thickness is 3.45 ± 0.5 mm. Due to the anisotropy of permanent magnets and the unique structure of axial flux motors, the magnets are suitable for parallel magnetization. Considering reasonable magnetic load and minimizing the risk of irreversible demagnetization, the magnet thickness is selected to be 3.45 mm.

[0038] Furthermore, as a preferred embodiment of this solution but not a limitation, the air gap between the stator and the rotor is 0.5±0.1mm. The joint disc motor has a high power density and torque density. At the same time, in order to reduce the amount of magnetic steel and reduce costs, it is suitable to adopt a small air gap so as to pursue a higher air gap magnetic density. At the same time, considering the requirements of the special matching process, the air gap is set to 0.5mm.

[0039] Furthermore, as a preferred embodiment of this solution, but not a limitation, the corresponding two magnets on the two stators have the same magnetic poles. A positioning shoulder is provided at a location on the exterior or interior of the rotor core to secure the radial mounting position of the magnets. The magnets are secured to the rotor core using instant adhesive. The two sets of magnets, positioned back-to-back, are assembled with opposite magnetization directions.

[0040] Furthermore, as a preferred embodiment of the present invention but not a limitation, the maximum speed of the disc-type axial motor is 2600 rpm and the frequency is 433.33 Hz.

[0041] Furthermore, as a preferred embodiment of this solution but not a limitation, the sum of the heights of the stator core and the teeth is 8 mm.

[0042] Furthermore, as a preferred embodiment of the present invention but not a limitation, the rotor core includes a main body 111, positioning shoulders 112 protruding from the front and rear sides of the main body, a boss 113 provided at the center of the main body and protruding to one side, a through hole 114 provided on the side of the boss, and an axial hole 115 provided on the boss.

[0043] The above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application. Other embodiments whose principles and basic structures are the same or similar to those of the present application are within the scope of protection of the present application.

Claims

1. A disc-type axial motor, characterized in that: include The rotor comprises a rotor core and magnets disposed on the front and rear sides of the rotor core and arranged along the circumference thereof; The stator comprises a stator core, teeth provided on one side of the stator core and arranged along the circumference thereof, and coils provided on the teeth; The two stators are respectively arranged at the front and rear sides of the rotor, and the teeth face the rotor.

2. The disc-type axial motor according to claim 1, characterized in that: The ratio of the magnet to the coil is 20:

18.

3. The disc-type axial motor according to claim 1, characterized in that: The outer diameter of the stator core is 76±1 mm, and the inner diameter is 57±1 mm.

4. The disc-type axial motor according to claim 1, characterized in that: The stator further includes a yoke portion, and the maximum magnetic flux density range of the teeth portion and the yoke portion is 1.4T-1.5T.

5. The disc-type axial motor according to claim 1, characterized in that: The thickness of the magnet is 3.45±0.5 mm.

6. The disc-type axial motor according to claim 1, characterized in that: The air gap between the stator and the rotor is 0.5±0.1 mm.

7. The disc-type axial motor according to claim 1, characterized in that: The magnetic poles of the two corresponding magnets on the two stators are the same.

8. The disc-type axial motor according to claim 1, characterized in that: The maximum speed of the disc-type axial motor is 2600 rpm and the frequency is 433.33 Hz.

9. The disc-type axial motor according to claim 1, characterized in that: The sum of the heights of the stator core and the teeth is 8 mm.

10. The disc-type axial motor according to claim 1, characterized in that: The rotor core includes a body, positioning shoulders protruding from the front and rear sides of the body, a boss provided at the center of the body and protruding to one side, a through hole provided on the side of the boss, and an axial hole provided on the boss.

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