CN210246577U - Novel sensor external rotor motor - Google Patents
Novel sensor external rotor motor Download PDFInfo
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- CN210246577U CN210246577U CN201921603909.0U CN201921603909U CN210246577U CN 210246577 U CN210246577 U CN 210246577U CN 201921603909 U CN201921603909 U CN 201921603909U CN 210246577 U CN210246577 U CN 210246577U
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Abstract
The utility model relates to a novel sensor external rotor motor, which comprises a stator unit, a rotor unit and a position encoder; the stator unit comprises a stator main shaft and a stator armature winding fixedly arranged on the stator main shaft; the rotor unit comprises an outer rotor and rotor magnetic steel, the outer rotor surrounds the stator armature winding and is rotatably connected to the stator main shaft, and the rotor magnetic steel is circumferentially arranged in the outer rotor at intervals; the position encoder sequentially comprises a mounting bracket, a signal processing board, an exciting and receiving coil board and an induction board, wherein the mounting bracket is fixed on the stator main shaft, the signal processing board and the exciting and receiving coil board are arranged on the mounting bracket, the induction board is fixed on the inner wall of the outer rotor and keeps a gap with the exciting and receiving coil board, the induction board and the exciting and receiving coil board are parallel to each other, and the central points of the induction board and the exciting and receiving coil board are both positioned on the rotating central shaft of the outer rotor. The utility model discloses have the good effect of service environment suitability.
Description
Technical Field
The utility model belongs to the technical field of rotor electric machine's technique and specifically relates to a novel sensor external rotor electric machine is related to.
Background
Currently, ac motors have become the most widely used power devices. However, due to the limitations of mechanical installation space, precision and other conditions, in various practical applications, corresponding transmission and braking devices, such as gear sets, belt pulleys and other components, need to be matched, so that the size and the weight are large, and the reliability is low and the service life is short due to mechanical vibration or abrasion, and frequent maintenance is required.
The wheel hub motor, namely the motor arranged in the wheel, has the greatest characteristic that power, transmission and braking devices are integrated into the wheel hub, so that the mechanical part of electric transmission is greatly simplified, and the wheel hub motor becomes a mainstream power device on new energy automobiles, balance cars, electric bicycles, mobile robots and the like. In addition, the hub motor has the advantages of high power density and energy transmission efficiency, large output torque, fast dynamic response, high control progress, no influence of oil, dust and other pollutants on work, high reliability, low failure rate, convenience in maintenance and the like.
The mature application of the hub motor cannot be promoted by the advanced drive control technology, and the control modes of the hub motor are various and the general modes are as follows: six-step square wave control, sine control, vector directional control and direct torque control. In either case, it is necessary to detect the rotational speed and angular position of the motor in real time for accurate speed and position control. The current mainstream position detection is to use a photoelectric encoder installed on the motor to obtain the rotation speed and position information of the motor. However, the photoelectric encoder has high cost, is easy to damage, has high requirements on the environment, and is easily influenced by oil stains and dust.
Therefore, for the defect of high requirement on the environment of the photoelectric encoder, a novel encoder is needed to overcome the defect of the photoelectric encoder.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a novel sensor external rotor electric machine has the characteristics that service environment adaptability is good.
The above technical purpose of the present invention can be achieved by the following technical solutions:
a novel sensor outer rotor motor comprises a stator unit, a rotor unit and a position encoder;
the stator unit comprises a stator main shaft and a stator armature winding fixedly arranged on the stator main shaft;
the rotor unit comprises an outer rotor and rotor magnetic steel, the outer rotor surrounds the stator armature winding and is rotatably connected to the stator main shaft, and the rotor magnetic steel is circumferentially arranged in the outer rotor at intervals;
the position encoder sequentially comprises a mounting bracket, a signal processing board, an exciting and receiving coil board and an induction board, wherein the mounting bracket is fixed on the stator main shaft, the signal processing board and the exciting and receiving coil board are arranged on the mounting bracket, the induction board is fixed on the inner wall of the outer rotor and keeps a gap with the exciting and receiving coil board, the induction board and the exciting and receiving coil board are parallel to each other, and the central points of the induction board and the exciting and receiving coil board are both positioned on the rotating central shaft of the outer rotor.
Through above-mentioned technical scheme, signal processing board and excitation and receiving coil plate set up on the installing support, and the tablet is fixed on the outer rotor inner wall, and whole position encoder's simple to operate to utilize the magnetic field change to reach the mode that detects stator main shaft rotational position, have better service environment adaptability for photoelectric encoder, and the cost is lower is difficult to damage.
Preferably, the outer rotor comprises a rotor housing, a first end cover and a second end cover;
rotor magnet steel circumference interval arrangement is on rotor case's inner wall, first end cover and second end cover pass through the screw installation at rotor case's both ends, the center of first end cover and second end cover all passes through the bearing and connects on the stator main shaft.
Through above-mentioned technical scheme, first end cover and second end cover pass through the mode of screw installation, reach first end cover and second end cover detachable purpose to improve the convenience to the convenience of position encoder installation and the convenience of maintenance.
Preferably, the end of the stator main shaft penetrates through the center of the first end cover and/or the second end cover.
Through the technical scheme, the stator spindle penetrates out of the first end cover or the second end cover so that the outer rotor motor forms a single-shaft outer rotor motor structure, and the end part of the stator spindle penetrates out of the first end cover and the second end cover so that the outer rotor motor forms a double-shaft outer rotor motor structure, so that the use adaptability of the outer rotor motor is further improved.
Preferably, a first O-ring seal is compressed between the first end cover and the rotor housing, and a second O-ring seal is compressed between the second end cover and the rotor housing.
Through above-mentioned technical scheme, the setting of first O type sealing washer and second O type sealing washer can improve this external rotor electric machine's leakproofness, prevents that external oil stain, dust from entering into in the rotor housing.
Preferably, the exciting and receiving coil plate is provided with an exciting coil and a receiving coil;
the exciting coil is used for passing high-frequency periodic alternating voltage and current and generating an alternating electromagnetic field;
the receiving coil is arranged in the alternating electromagnetic field generated by the exciting coil and outputs a voltage signal to the signal processing board based on the rotation influence of the induction board.
According to the technical scheme, the exciting coil is used for generating an alternating electromagnetic field through high-frequency periodic alternating voltage and current, the receiving coil is arranged in the alternating electromagnetic field generated by the exciting coil and generates induced electromotive force, when the rotor shell rotates and drives the induction plate to rotate, the alternating electromagnetic field of the exciting coil generates an eddy current field on the induction plate, the induction plate influences the electromagnetic coupling strength between the exciting coil and the receiving coil, voltage signals with different amplitudes are obtained on the receiving coil, the voltage signals are input into the signal processing plate, the signal processing plate converts the voltage signals into sine and cosine orthogonal differential signals to be output, and identification of the position and the rotating speed of the stator spindle is completed.
Preferably, the induction board comprises a support plate made of a non-electromagnetic induction material and a plurality of metal induction coils, the metal induction coils are circumferentially arranged on the surface of the support plate at equal intervals, and the metal induction coils face one side of the excitation and receiving coil board.
Through the technical scheme, when the metal induction coil rotates, the metal induction coil is influenced by the alternating electromagnetic field of the exciting coil to generate an eddy current field, so that the electromagnetic field on the exciting coil is weakened, the induced electromotive force in the receiving coil is changed due to the uneven alternating electromagnetic field, and the change is different according to the relative angle position of the induction plate and the receiving coil.
Preferably, a plurality of first positioning columns are circumferentially arranged on the mounting support at intervals, second positioning columns are coaxially arranged at the end parts of the first positioning columns, and the diameters of the second positioning columns are smaller than those of the first positioning columns;
the signal processing board is provided with a first positioning hole which is used for being matched with the first positioning column in an inserting mode, and the exciting and receiving coil board is provided with a second positioning hole which is used for being matched with the second positioning column in an inserting mode.
Through the technical scheme, the first positioning column is in plug-in fit with the first positioning hole to achieve the purpose of fixing the signal processing board, the second positioning column is in plug-in fit with the second positioning hole to achieve the purpose of fixing the exciting and receiving coil board, the signal processing board and the exciting and receiving coil board are convenient to disassemble, assemble and maintain, and the exciting and receiving coil board and the induction board can be guaranteed to be parallel.
Preferably, the stator main shaft is hollow inside and penetrates through to form a main shaft cavity, and the main shaft cavity is used for providing a mounting channel for the signal wire and the power wire.
Through the technical scheme, the arrangement of the cavity of the main shaft facilitates the wiring layout of the signal line and the power line.
To sum up, the utility model discloses a beneficial technological effect does:
the signal processing board and the exciting and receiving coil board are arranged on the mounting bracket, the induction board is fixed on the inner wall of the outer rotor, the whole position encoder is convenient to mount, the mode of detecting the rotating position of the stator main shaft is achieved by utilizing the change of the magnetic field, the photoelectric encoder has better service environment adaptability, and the photoelectric encoder is low in cost and not easy to damage.
Drawings
FIG. 1 is a schematic structural diagram of a two-shaft outer rotor motor in an embodiment;
FIG. 2 is a sectional view of a two-shaft outer rotor motor according to an embodiment;
FIG. 3 is an exploded schematic view of a dual-shaft outer rotor motor according to an embodiment;
FIG. 4 is a schematic structural diagram of a single-shaft outer rotor motor in an embodiment;
FIG. 5 is a sectional view of a single-shaft outer rotor motor according to the embodiment;
FIG. 6 is an exploded view of a single-shaft outer rotor motor according to an embodiment;
FIG. 7 is a schematic structural view of a mounting bracket according to an embodiment;
FIG. 8 is a schematic structural view of an example of a sensor board;
fig. 9 is a schematic structural diagram of the exciting and receiving coil plates in the embodiment.
Reference numerals: 1. a stator unit; 11. a stator main shaft; 12. a stator armature winding; 13. a main shaft cavity; 2. a rotor unit; 21. an outer rotor; 211. a rotor housing; 212. a first end cap; 213. a second end cap; 22. rotor magnetic steel; 3. a position encoder; 31. mounting a bracket; 32. a signal processing board; 33. exciting and receiving a coil plate; 331. an excitation coil; 332. a receiving coil; 34. an induction plate; 341. a carrier plate; 342. a metal induction coil; 35. a first positioning post; 36. a second positioning column; 37. a first positioning hole; 38. and a second positioning hole.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Referring to fig. 1 and 2, a novel sensor outer rotor motor includes a stator unit 1, a rotor unit 2, and a position encoder 3.
The stator unit 1 comprises a stator main shaft 11 and a stator armature winding 12, the stator armature winding 12 is fixedly installed on the outer surface of the stator main shaft 11, the interior of the stator main shaft 11 is hollow and penetrates through to form a main shaft cavity 13, the main shaft cavity 13 is arranged along the axial direction of the stator main shaft 11, and the main shaft cavity 13 is used for providing installation channels for signal lines and power lines.
The signal line is used for realizing data interaction between the outer rotor motor internal position encoder 3 and external equipment (such as a motor driver). The power lines are used for data interaction with external equipment (such as a motor driver), wherein the power lines pass through the spindle cavity 13 and penetrate out of the stator spindle 11 at the position of the stator armature winding 12 to be connected to the stator armature winding 12, and the power lines provide alternating current for the stator armature winding 12, so that the stator armature winding 12 generates a rotating magnetic field according to the alternating voltage.
Referring to fig. 2 and 3, the rotor unit 2 includes an outer rotor 21 and rotor magnetic steels 22, the outer rotor 21 surrounds the stator armature winding 12 and is rotatably connected to the stator spindle 11, the rotor magnetic steels 22 are circumferentially arranged in the outer rotor 21 at intervals, the rotor magnetic steels 22 are located corresponding to the stator armature winding 12, and a certain interval exists between the rotor magnetic steels 22 and the stator armature winding 12. The length direction of the rotor magnetic steel 22 is the same as the direction of the rotation center axis of the outer rotor motor.
The motor driver outputs alternating voltage to be transmitted to the stator armature winding 12 through a power line, so that the stator armature winding 12 generates a rotating magnetic field, the magnetic field interacts with the magnetic field generated by the rotor magnetic steel 22 to generate tangential electromagnetic traction, and the outer rotor 21 and the rotor magnetic steel 22 are driven to rotate synchronously.
The outer rotor 21 includes a rotor housing 211, a first end cap 212, and a second end cap 213. The rotor housing 211 is cylindrical, the rotor housing 211 is hollow to penetrate through two end faces thereof, and the rotor magnetic steels 22 are circumferentially arranged on the inner wall of the rotor housing 211 at intervals. The first end cover 212 and the second end cover 213 are installed at both ends of the rotor housing 211 by screws, and the centers of the first end cover 212 and the second end cover 213 are connected to the stator main shaft 11 by bearings. A first O-ring seal is compressed between the first end cap 212 and the rotor housing 211, and a second O-ring seal is compressed between the second end cap 213 and the rotor housing 211.
In one embodiment, referring to fig. 4, in order to meet the use requirement of the single-shaft external rotor motor, the end of the stator main shaft 11 penetrates through the center of the first end cover 212 or the second end cover 213, and the structure of the single-shaft external rotor motor can be as shown in fig. 5 and 6. In another embodiment, referring to fig. 1, for use of the dual-shaft external rotor motor, the end of the stator main shaft 11 penetrates the centers of the first end cover 212 and the second end cover 213. The present embodiment is explained by taking a dual-shaft external rotor motor as an example.
In order to ensure the normal use of the external rotor motor, a damping unit including, but not limited to, a solid tire or a pneumatic tire is fixedly disposed on the outer surface of the rotor housing 211.
In the present application, as shown in fig. 3 and 4, the position encoder 3 sequentially includes a mounting bracket 31, a signal processing board 32, an exciting and receiving coil board 33, and an induction board 34, the mounting bracket 31 is disposed in a disc shape, the mounting bracket 31 is fixedly mounted on the stator main shaft 11, and the center of the mounting bracket 31 and the stator main shaft 11 are disposed coaxially. In one embodiment, mounting bracket 31 is made of a non-electromagnetically inductive material, such as plastic or the like.
The signal processing board 32 and the excitation and reception coil board 33 are provided on the mounting bracket 31, the signal processing board 32 and the excitation and reception coil board 33 are parallel to each other with a gap maintained therebetween, and the centers of the signal processing board 32 and the excitation and reception coil 332 are located on the rotation center axis of the outer rotor motor.
It should be noted that, as shown in fig. 7, a plurality of first positioning posts 35 are circumferentially arranged on the mounting bracket 31 at intervals, second positioning posts 36 are coaxially arranged at the end portions of the first positioning posts 35, and the diameter of each second positioning post 36 is smaller than that of each first positioning post 35; thus, a step is formed between the first positioning post 35 and the second positioning post 36, the signal processing board 32 is provided with a first positioning hole 37 for fitting with the first positioning post 35, and the exciting and receiving coil board 33 is provided with a second positioning hole 38 for fitting with the second positioning post 36.
In one embodiment, a tight fit is used between the first positioning post 35 and the first positioning hole 37. The second positioning column 36 and the second positioning hole 38 are tightly fitted, the first positioning hole 37 on the signal processing board 32 is aligned with the first positioning column 35, the first positioning column 35 is inserted into the first positioning hole 37, the signal processing board 32 is attached to the mounting bracket 31, and the signal processing board 32 can be fixed on the mounting bracket 31.
Similarly, the second positioning hole 38 of the exciting and receiving coil plate 33 is aligned with the second positioning post 36, the second positioning post 36 is inserted into the second positioning hole 38, and the exciting and receiving coil plate 33 is attached to the step, thereby completing the fixing of the exciting and receiving coil plate 33. Thus, the signal processing board 32 and the exciting and receiving coil board 33 are kept parallel and fixed to each other, and the signal processing board 32 and the exciting and receiving coil board 33 are electrically connected by a wire.
As shown in fig. 9, the signal processing board 32 and the exciting and receiving coil board 33 are both PCB boards, wherein the signal processing board 32 is provided with a signal processing circuit and an oscillating circuit, the exciting and receiving coil board 33 is provided with an exciting coil 331 and a receiving coil 332, the signal processing board 32 and the exciting and receiving coil 332 are connected by a conducting wire, that is, the oscillating circuit is connected to the exciting coil 331, the signal processing circuit is connected to the receiving coil 332, and the signal wire passes through the spindle cavity 13 and is connected to the signal processing circuit of the signal processing board 32.
The oscillation circuit is used to generate a high-frequency periodic alternating voltage and current, and the exciting coil 331 is used to pass the high-frequency periodic alternating voltage and current and generate an alternating electromagnetic field.
The receiving coil 332 is disposed within the alternating electromagnetic field generated by the exciting coil 331, and generates an induced electromotive force.
It should be noted that, as shown in fig. 8, the induction plate 34 is fixed to the inner wall of the outer rotor 21 with a gap from the exciting and receiving coil plate 33, the induction plate 34 and the exciting and receiving coil plate 33 are parallel to each other, and the center points of both are located on the rotation center axis of the outer rotor 21. The inductive board 34 includes a carrier 341 made of non-electromagnetic inductive material, and a plurality of metal inductive coils 342, the metal inductive coils 342 are annular closed metal wires, the metal inductive coils 342 are circumferentially disposed on the surface of the carrier 341 at equal intervals, and the metal inductive coils 342 face the exciting and receiving coil board 33.
Therefore, when the outer rotor 21 rotates and drives the induction plate 34 to rotate, the induction plate 34 is influenced by the alternating electromagnetic field of the excitation coil 331 to generate an eddy current field, so that the electromagnetic field on the excitation coil 331 is weakened, the induced electromotive force in the receiving coil 332 is changed due to the uneven alternating electromagnetic field, voltage signals with different amplitudes are obtained on the receiving coil 332, the voltage signals are input into the signal processing board 32, the voltage signals are converted into sine and cosine orthogonal differential signals through the signal processing circuit, the sine and cosine orthogonal differential signals are output to external equipment (a motor driver) through signal lines, and the sine and cosine orthogonal differential signals are motor position coding signals which can be recognized by the motor driver and determine the position and the rotating speed of the outer rotor 21.
The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.
Claims (8)
1. A novel sensor outer rotor motor comprises a stator unit (1), a rotor unit (2) and a position encoder (3);
the stator unit (1) comprises a stator main shaft (11) and a stator armature winding (12) fixedly arranged on the stator main shaft (11);
the rotor unit (2) comprises an outer rotor (21) and rotor magnetic steel (22), the outer rotor (21) surrounds the stator armature winding (12) and is rotatably connected to the stator main shaft (11), and the rotor magnetic steel (22) is circumferentially arranged in the outer rotor (21) at intervals;
the position encoder is characterized in that the position encoder (3) sequentially comprises a mounting bracket (31), a signal processing board (32), an exciting and receiving coil board (33) and an induction board (34), the mounting bracket (31) is fixed on a stator main shaft (11), the signal processing board (32) and the exciting and receiving coil board (33) are arranged on the mounting bracket (31), the induction board (34) is fixed on the inner wall of the outer rotor (21) and keeps a gap with the exciting and receiving coil board (33), the induction board (34) and the exciting and receiving coil board (33) are parallel to each other, and the central points of the two are located on the rotating central shaft of the outer rotor (21).
2. The novel sensor external rotor electric machine according to claim 1, wherein the external rotor (21) comprises a rotor housing (211), a first end cover (212) and a second end cover (213);
rotor magnet steel (22) circumference interval arrangement is on the inner wall of rotor housing (211), first end cover (212) and second end cover (213) pass through the both ends of mounting screw at rotor housing (211), the center of first end cover (212) and second end cover (213) all passes through the bearing and connects on stator main shaft (11).
3. The novel sensor external rotor motor according to claim 2, wherein the end of the stator main shaft (11) penetrates through the center of the first end cover (212) and/or the second end cover (213).
4. The novel sensor external rotor motor as claimed in claim 2, wherein a first O-ring seal is compressed between the first end cover (212) and the rotor housing (211), and a second O-ring seal is compressed between the second end cover (213) and the rotor housing (211).
5. The novel sensor external rotor motor according to claim 1, wherein the excitation and reception coil plate (33) is provided with an excitation coil (331) and a reception coil (332);
the exciting coil (331) is used for passing high-frequency periodic alternating voltage and current and generating an alternating electromagnetic field;
the receiving coil (332) is arranged in the alternating electromagnetic field generated by the exciting coil (331) and outputs a voltage signal to the signal processing board (32) based on the rotating influence of the induction board (34).
6. The novel sensor external rotor motor as claimed in claim 1, wherein the induction board (34) comprises a carrier board (341) made of non-electromagnetic induction material, and a plurality of metal induction coils (342), the metal induction coils (342) are circumferentially arranged on the surface of the carrier board (341) at equal intervals, and the metal induction coils (342) face to one side of the exciting and receiving coil board (33).
7. The novel sensor external rotor motor as claimed in claim 1, wherein a plurality of first positioning columns (35) are circumferentially arranged on the mounting bracket (31) at intervals, second positioning columns (36) are coaxially arranged at the end parts of the first positioning columns (35), and the diameters of the second positioning columns (36) are smaller than the diameters of the first positioning columns (35);
the signal processing board (32) is provided with a first positioning hole (37) which is used for being matched with the first positioning column (35) in an inserted mode, and the exciting and receiving coil board (33) is provided with a second positioning hole (38) which is used for being matched with the second positioning column (36) in an inserted mode.
8. The novel sensor external rotor motor according to claim 1, wherein the stator main shaft (11) is hollow inside and penetrates through to form a main shaft cavity (13), and the main shaft cavity (13) is used for providing a mounting channel for signal lines and power lines.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921603909.0U CN210246577U (en) | 2019-09-24 | 2019-09-24 | Novel sensor external rotor motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921603909.0U CN210246577U (en) | 2019-09-24 | 2019-09-24 | Novel sensor external rotor motor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210246577U true CN210246577U (en) | 2020-04-03 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921603909.0U Active CN210246577U (en) | 2019-09-24 | 2019-09-24 | Novel sensor external rotor motor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210246577U (en) |
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2019
- 2019-09-24 CN CN201921603909.0U patent/CN210246577U/en active Active
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