An electric machine

Abstract

A motor comprises a stator and a rotor, the rotor comprises a magnetic piece and a rotor shaft, the magnetic piece is connected with the rotor shaft, the stator comprises a stator yoke and a flexible piece, the stator yoke has a receiving cavity, the magnetic piece is located in the receiving cavity, the flexible piece is arranged in the receiving cavity in a winding mode, the flexible piece is located on the inner wall of the stator yoke, the flexible piece comprises a stator winding, the stator yoke comprises n stator yoke parts, n is an integer, n is greater than or equal to 2, the n stator yoke parts are arranged in the circumferential direction of the stator yoke, the central angle of each stator yoke part is alpha, 0°< alpha ≤180°. In the assembly process, each stator yoke part can be attached to the outer wall of the flexible piece from the outer periphery of the wound flexible piece, which reduces the scratching of the flexible piece by the glue during assembly and improves the reliability of the bonding between the flexible piece and the stator yoke.

Description

Technical Field

[0001] This application relates to the field of motor technology, and more particularly to a motor. Background Technology

[0002] Slotless AC motors are widely used in applications requiring small, high-performance motors, such as robots and medical equipment. Due to the large size and manufacturing difficulties of motors, miniaturization is a crucial product challenge. In related technologies, stacked flexible components are used as a stator winding form of the motor. Specifically, two flexible components are stacked, wound, and then assembled into a stator yoke whose inner wall is coated with adhesive and bonded to the yoke. To ensure concentricity between the flexible component and the stator yoke, the difference between the outer diameter of the flexible component and the inner diameter of the stator yoke should be as small as possible. However, if the difference is too small, when the flexible component is installed into the stator yoke, some adhesive will move, resulting in uneven distribution of adhesive on the inner wall of the stator yoke. The reliability of the bonding between the flexible component and the stator yoke needs further improvement. Summary of the Invention

[0003] The purpose of this application is to provide a motor that improves the reliability of bonding between the flexible component and the stator yoke.

[0004] An electric motor includes a stator and a rotor. The rotor includes a magnetic element and a rotor shaft. The magnetic element is connected to the rotor shaft. The stator includes a stator yoke and a flexible element. The stator yoke has a receiving cavity. The magnetic element is located in the receiving cavity. The flexible element is wound in the receiving cavity and disposed on the inner wall of the stator yoke. The flexible element includes a stator winding. The stator yoke includes n stator yoke portions, where n ≥ 2 and n is an integer. The n stator yoke portions are arranged circumferentially on the stator yoke. The central angle of each stator yoke portion is α, where 0° < α ≤ 180°.

[0005] An electric motor includes a stator, which includes a stator yoke and a flexible member. The stator yoke has a receiving cavity, and the flexible member is wound in the receiving cavity and disposed on the inner wall of the stator yoke. The flexible member includes a stator winding. The stator yoke includes n stator yoke portions, where n ≥ 2 and n is an integer. The n stator yoke portions are arranged circumferentially on the stator yoke. The central angle of each stator yoke portion is α, where 0° < α ≤ 180°. During assembly, each stator yoke portion can be attached from the outer periphery of the wound flexible member to the outer wall of the flexible member, reducing the scraping of the adhesive by the flexible member during assembly and improving the reliability of the bonding between the flexible member and the stator yoke. Attached Figure Description

[0006] Figure 1 This is a partial structural diagram of the motor in this application;

[0007] Figure 2 This is a cross-sectional view of the motor of this application;

[0008] Figure 3 This is a schematic diagram of the structure of the flexible component in this application;

[0009] Figure 4 This is a top view schematic diagram of the stator yoke of this application, including two stator yoke sections;

[0010] Figure 5 A top view of the stator yoke of this application, comprising three stator yoke portions, each with a central angle of 120°.

[0011] Figure 6 This is a top view of the stator yoke of this application, which includes three stator yoke portions, one of which has a central angle of 180°.

[0012] Figure 7 This is a schematic diagram of the structure of the flexible circuit board of this application before winding, which has three-phase windings and two coils in each phase winding.

[0013] Figure 8 for Figure 7 A schematic diagram of the coil arrangement within the A-phase stator winding;

[0014] Figure 9 for Figure 7 A schematic diagram of the coil arrangement within the B-phase stator winding;

[0015] Figure 10 for Figure 7 A schematic diagram of the coil arrangement within the C-phase stator winding;

[0016] Figure 11 This is a schematic diagram of the structure of the flexible circuit board of this application before winding, which has three-phase windings and each phase winding has three coils.

[0017] Figure 12 for Figure 11 A schematic diagram of the coil arrangement within the A-phase stator winding;

[0018] Figure 13 for Figure 11 A schematic diagram of the coil arrangement within the B-phase stator winding;

[0019] Figure 14 for Figure 11 A schematic diagram of the coil arrangement within the C-phase stator winding.

[0020] Figure label:

[0021] Stator yoke 1, stator yoke section 11, first stator yoke section 12, second stator yoke section 13, third stator yoke section 14, silicon steel sheet 15.

[0022] Flexible component 2, substrate 21, first coil 221, first sub-oblique segment 2211, second sub-oblique segment 2212, third sub-oblique segment 2213, fourth sub-oblique segment 2214, first vertical segment 2215, second vertical segment 2216, second coil 222, third coil 223, fourth coil 224, fifth coil 225, sixth coil 226, seventh coil 227, eighth coil 228, ninth coil 229, first conductive layer 23, second conductive layer 24, first conductive portion 25, first sub-conductive portion 251, second sub-conductive portion 252, second conductive portion 26, third sub-conductive portion 261, fourth sub-conductive portion 262, fifth sub-conductive portion 263, terminal 27.

[0023] Magnetic field detection component 3, circuit control board 31, Hall sensor 32

[0024] First end cap 4, second end cap 5, first bearing 61, second bearing 62.

[0025] Rotor 7, magnetic component 71, rotor shaft 72. Detailed Implementation

[0026] refer to Figures 1-4 An electric motor includes a stator and a rotor 7. The rotor 7 includes a magnetic element 71 and a rotor shaft 72. The magnetic element 71 is connected to the rotor shaft 72. The stator includes a stator yoke 1 and a flexible element 2. The stator yoke 1 has a receiving cavity. The magnetic element 71 is located in the receiving cavity. The flexible element 2 is wound in the receiving cavity and disposed on the inner wall of the stator yoke 1. The flexible element 2 includes a stator winding. The stator yoke 1 includes n stator yoke portions 11, where n ≥ 2 and n is an integer. The n stator yoke portions 11 are arranged circumferentially on the stator yoke 1. The central angle of each stator yoke portion 11 is α, where 0° < α ≤ 180°.

[0027] An electric motor includes a stator, which includes a stator yoke 1 and a flexible member 2. The stator yoke 1 has a receiving cavity, and the flexible member 2 is wound in the receiving cavity and disposed on the inner wall of the stator yoke 1. The flexible member 2 includes a stator winding. The stator yoke 1 includes n stator yoke portions 11, where n ≥ 2 and n is an integer. The n stator yoke portions 11 are arranged circumferentially on the stator yoke 1. The central angle of each stator yoke portion 11 is α, where 0° < α ≤ 180°. During assembly, each stator yoke portion 11 can be attached from the outer periphery of the wound flexible member 2 to the outer wall of the flexible member 2, reducing the scraping of the adhesive by the flexible member 2 during assembly and improving the reliability of the bonding between the flexible member 2 and the stator yoke 1.

[0028] When the motor is running at high speed, due to vibration, special attention needs to be paid to the reliability of the bonding between the magnetic component 71 and the stator yoke 1. If the adhesive is not applied evenly, resulting in partial bonding and partial non-bonding, or insufficient adhesive in some areas and excessive adhesive in others, the flexible component 2 and the stator yoke 11 may not be bonded or may have a weak bond. As the motor operates for longer periods, the flexible component 2 may detach from the stator yoke 11, or even completely detach, leading to a decrease in the concentricity of the flexible component 2 and the rotor 7, which in turn affects the bearings of the rotor shaft 72. To address issues such as uneven wear and even motor failure, this application addresses this by dividing the stator yoke 1 into sections and placing them around the outer periphery of the flexible component 2. During assembly, each stator yoke section 11 can be attached from the outer periphery of the wound flexible component 2 to the outer wall of the flexible component 2, forming a complete circular stator yoke 1 from multiple stator yoke sections 11. This reduces the uneven distribution of adhesive caused by scratching during the assembly of the flexible component 2 in related technologies, improves the reliability of the connection between the flexible component 2 and the stator yoke 1, reduces uneven wear of the motor, and improves the service life and control accuracy of the motor.

[0029] refer to Figure 4 The stator yoke 1 includes two stator yoke portions 11, each with a central angle of 180°. The two side walls of the two stator yoke portions 11 are respectively joined together, and the two side walls of the two stator yoke portions 11 can be bonded with glue and / or welded.

[0030] refer to Figure 2 The stator yoke 1 includes multiple silicon steel sheets 15, which are stacked and bonded together with glue or welded. The silicon steel sheets 15 are directly stamped to improve the accuracy of the stator yoke 1. At the same time, the semi-circular silicon steel sheets 15 can be continuously stamped to reduce waste and thus reduce costs.

[0031] The outer wall of the flexible component 2 is bonded to the inner wall of the stator yoke 1, which facilitates manufacturing.

[0032] refer to Figure 2 The motor includes a first end cover 4, a second end cover 5, a first bearing 61, and a second bearing 62. The first end cover 4 is located at one end of the stator yoke 1, and the second end cover 5 is located at the other end of the stator yoke 1. The first bearing 61 is installed on the first end cover 4, and the second bearing 62 is installed on the second end cover 5. The first bearing 61 and the second bearing 62 are respectively sleeved on the rotor shaft 72. When the flexible component 2 is energized, it generates a magnetic field and interacts with the magnetic field of the magnetic component 71, thereby driving the magnetic component 71 to drive the rotor shaft 72 to rotate.

[0033] refer to Figures 7-8The flexible member 2 has at least two conductive layers. The flexible member 2 has a stator winding in the conductive layers. The conductive layers include a first conductive layer 23 and a second conductive layer 24. The flexible member 2 includes a substrate 21. The first conductive layer 23 is located on one side of the substrate 21, and the second conductive layer 24 is located on the other side of the substrate 21. The stator winding includes a first phase stator winding. The first phase stator winding includes a first coil 221. A portion of the first coil 221 is located in the first conductive layer 23, and another portion of the first coil 221 is located in the second conductive layer 24. The flexible member 2 includes a first conductive portion 25 that penetrates the substrate 21. The first conductive portion 25 electrically connects the portion of the first coil 221 located in the first conductive layer 23 and the portion of the first coil 221 located in the second conductive layer 24. This can reduce the risk of coil misalignment, thereby improving the magnetic field balance and consistency.

[0034] refer to Figures 7-10 Each phase winding includes at least two coils connected in series, and the flexible member 2 includes a second conductive part 26, through which two coils of the same phase winding are electrically connected.

[0035] The second conductive portion 26 is disposed near the center of the substrate 21 relative to the first conductive portion 25. The first conductive portion 25 includes a plurality of first sub-conductive portions 251 and a plurality of second sub-conductive portions 252. The first sub-conductive portions 251 and the second sub-conductive portions 252 are located on opposite sides of the substrate 21, and the second conductive portion 26 is located between the first sub-conductive portions 251 and the second sub-conductive portions 252.

[0036] The coil includes oblique segments. In the same coil, the oblique segment located on the first conductive layer 23 is defined as the first oblique segment, and the oblique segment located on the second conductive layer 24 is defined as the second oblique segment. The first sub-conductive part 251 is electrically connected to the adjacent first oblique segment and the second oblique segment located on one side of the substrate 21, and the second sub-conductive part 252 is electrically connected to the adjacent first oblique segment and the second oblique segment located on the other side of the substrate 21.

[0037] The first sub-conductive portion 251 is arranged in the length direction of the flexible member 2 (before winding), and the second sub-conductive portion 252 is arranged in the length direction of the flexible member 2 (before winding). The first sub-conductive portion 251 and the second sub-conductive portion 252 are parallel.

[0038] The first oblique segment includes multiple first sub-oblique segments 2211 and multiple second sub-oblique segments 2212 arranged side by side; the second oblique segment includes multiple third sub-oblique segments 2213 and multiple fourth sub-oblique segments 2214 arranged side by side; the coil includes a vertical segment. In the same coil, the vertical segment located in the first conductive layer 23 is defined as the first vertical segment 2215, and the vertical segment located in the second conductive layer 24 is defined as the second vertical segment 2216. The first vertical segment 2215 is electrically connected to the first sub-oblique segments 2211 and the second sub-oblique segments 2212, and the second vertical segment 2216 is electrically connected to the third sub-oblique segments 2213 and the fourth sub-oblique segments 2214.

[0039] Next, taking a three-phase motor as an example, refer to... Figures 6-9 Each phase has two coils, including a first coil 221, a second coil 222, a third coil 223, a fourth coil 224, a fifth coil 225, and a sixth coil 226. The first coil 221 and the fourth coil 224 form the A-phase winding, the third coil 223 and the sixth coil 226 form the B-phase winding, and the second coil 222 and the fifth coil 225 form the C-phase winding. In the attached diagram, the coils represented by solid lines are located in the first conductive layer 23, and those represented by dashed lines are located in the second conductive layer 24.

[0040] The second conductive part 26 includes a third sub-conductive part 261, a fourth sub-conductive part 262 and a fifth sub-conductive part 263. The third sub-conductive part 261 is electrically connected to the first coil 221 and the fourth coil 224. The fourth sub-conductive part 262 is electrically connected to the third coil 223 and the sixth coil 226. The fifth sub-conductive part 263 is electrically connected to the second coil 222 and the fifth coil 225.

[0041] refer to Figures 7-10 The first vertical segment 2215 and the second vertical segment 2216 of the same phase are arranged opposite to each other. That is, the second vertical segment 2216 of the first coil 221 is arranged opposite to the first vertical segment 2215 of the fourth coil 224. In the projection of the first surface, the second vertical segment 2216 of the first coil 221 and the first vertical segment 2215 of the fourth coil 224 coincide. The same arrangement is made for phase B and phase C, which will not be described in detail here.

[0042] refer to Figures 11-14Each phase winding has three coils: coil 221, coil 222, coil 223, coil 224, coil 225, coil 226, coil 227, coil 228, and coil 229. Coils 221, 222, and 223 form phase A winding; coils 224, 225, and 226 form phase B winding; and coils 227, 228, and 229 form phase C winding. In the attached diagram, solid lines represent the coils located in the first conductive layer 23, while dashed lines represent the coils located in the second conductive layer 24.

[0043] The second conductive part 26 includes a third sub-conductive part 261, a fourth sub-conductive part 262, and a fifth sub-conductive part 263. The third sub-conductive part 261 is electrically connected to the first coil 221 and the third coil 223. The third coil 223 is directly connected to the second coil 222. The fourth sub-conductive part 262 is electrically connected to the fourth coil 224 and the sixth coil 226. The sixth coil 226 and the fifth coil 225 are directly connected. The fifth sub-conductive part 263 is electrically connected to the seventh coil 227 and the ninth coil 229. The ninth coil 229 and the eighth coil 228 are directly connected.

[0044] refer to Figures 11-14 The first vertical segment 2215 of one phase and the second vertical segment 2216 of another phase are arranged opposite to each other. That is, the second vertical segment 2216 of phase A is arranged opposite to the first vertical segment 2215 of phase B, and the second vertical segment 2216 of phase B is arranged opposite to the first vertical segment 2215 of phase C. In the projection of the first surface, the second vertical segment 2216 of phase A coincides with the first vertical segment 2215 of phase B, and the second vertical segment 2216 of phase B coincides with the first vertical segment 2215 of phase C. This will not be elaborated here.

[0045] The first conductive portion 25 can be formed by drilling a hole in the substrate 21 using methods such as mechanical drilling or laser drilling, and then plating copper into the hole. The second conductive portion 26 can be formed in the same way, which will not be described in detail here. The two ends of the first conductive portion 25 are basically flush with the upper and lower ends of the hole. Of course, it can also be set according to specific requirements, which will not be described in detail here.

[0046] refer to Figure 1 The flexible component 22 is provided with a terminal 27 for connecting to an external power source. The flexible component 22 includes at least two conductive layers, and multiple sets of coils are arranged in the conductive layers. The multiple sets of coils are arranged along the length of the flexible component 22 and are directly or indirectly electrically connected to the terminal 27.

[0047] The substrate 21 is made of polyimide or other high-temperature resistant and insulating materials to prevent short circuits between the two conductive layers. The coil is disposed within the conductive layer, which protects the coil. The flexible component 22 can be manufactured using existing production processes, employing photolithography, etching, and deposition techniques to achieve high-precision manufacturing of the coil.

[0048] The motor described in this application can be used in medical robots, humanoid robots, drones, gimbals, aerospace, etc., which will not be elaborated here.

[0049] refer to Figures 1-2 The motor also includes a magnetic field detection component 3, which comprises a circuit control board 31 and a Hall sensor 32. The Hall sensor 32 is mounted on the circuit control board 31, which is connected to the side of the flexible component 22 with a terminal 27. The flexible component 22 is wound into a cylindrical shape, and the circuit control board 31 is annular in shape, covering the end of the cylindrical flexible component 22. Alternatively, the circuit control board 31 can also be in the form of the flexible component 22. By designing the circuit control board 31 as flexible, it is easier to integrate the circuit control board 31 and the flexible component 22 during manufacturing, allowing the Hall sensor 32 to be electrically connected to an external circuit via the terminal 27. This significantly improves the space utilization of the motor, reduces the structural volume, and enhances wiring convenience.

[0050] Another structure for stator yoke 1 is provided, see reference. Figure 5 The stator yoke includes three stator yoke portions 11, each with a central angle of 120°. One side wall of each stator yoke portion 11 is connected to the side wall of one of the stator yoke portions 11, and the other side wall of each stator yoke portion 11 is connected to the side wall of another stator yoke portion 11.

[0051] Another structure for stator yoke 1 is provided, see reference. Figure 6 The stator yoke 1 includes a first stator yoke portion 12, a second stator yoke portion 13, and a third stator yoke portion 14. The circular angle of the first stator yoke portion 12 is 180°, the central angle of the second stator yoke portion 13 is 90°, and the central angle of the third stator yoke portion 14 is 90°. One side wall of the second stator yoke portion 13 is connected to one side wall of the first stator yoke portion 12, one side wall of the third stator yoke portion 14 is connected to the other side wall of the first stator yoke portion 12, and the other side wall of the second stator yoke portion 13 is connected to the other side wall of the third stator yoke portion 14.

[0052] Of course, the number of stator yokes 11 can be 4 / 5 / 6 / 7 / 8, etc., as long as the sum of the central angles is 360°. For example, the stator yoke can include 4 stator yokes 11, each with a central angle of 90°, or with central angles of 60°, 60°, 120° and 120° respectively. One side wall of each stator yoke 11 is connected to the side wall of one of the stator yokes 11, and the other side wall of each stator yoke 11 is connected to the side wall of another stator yoke 11. This will not be elaborated here.

Claims

1. An electric motor, characterized in that, The motor includes a stator and a rotor (7). The rotor includes a magnetic component (71) and a rotor shaft (72). The magnetic component (71) is connected to the rotor shaft (72). The stator includes a stator yoke (1) and a flexible component (2). The stator yoke (1) has a receiving cavity. The magnetic component (71) is located in the receiving cavity. The flexible component (2) is wound in the receiving cavity. The flexible component (2) is disposed on the inner wall of the stator yoke (1). The flexible component (2) includes a stator winding. The stator yoke (1) includes n stator yoke parts (11), where n ≥ 2 and n is an integer. The n stator yoke parts (11) are arranged circumferentially on the stator yoke (1). The central angle of each stator yoke part (11) is α, where 0° < α ≤ 180°.

2. The motor according to claim 1, characterized in that, The stator yoke (1) includes two stator yoke parts (11), each with a central angle of 180°, and the two side walls of the two stator yoke parts (11) are respectively connected.

3. The motor according to claim 1, characterized in that, The stator yoke (1) includes three stator yoke portions (11), each stator yoke portion (11) having a central angle of 120°. One side wall of each stator yoke portion (11) is connected to the side wall of one of the stator yoke portions (11), and the other side wall of each stator yoke portion (11) is connected to the side wall of another stator yoke portion (11).

4. The motor according to claim 1, characterized in that, The stator yoke (1) includes a first stator yoke portion (12), a second stator yoke portion (13), and a third stator yoke portion (14). The central angle of the first stator yoke portion (12) is 180°, the central angle of the second stator yoke portion (13) is 90°, and the central angle of the third stator yoke portion (14) is 90°. One side wall of the second stator yoke portion (13) is connected to one side wall of the first stator yoke portion (12), one side wall of the third stator yoke portion (14) is connected to the other side wall of the first stator yoke portion (12), and the other side wall of the second stator yoke portion (13) is connected to the other side wall of the third stator yoke portion (14).

5. The motor according to claim 1, characterized in that, The stator yoke (1) includes a plurality of silicon steel sheets (15), which are stacked together.

6. The motor according to any one of claims 1-5, characterized in that, The outer wall of the flexible component (2) is bonded to the inner wall of the stator yoke (1).

7. The motor according to any one of claims 1-5, characterized in that, The motor includes a first end cover (4), a second end cover (5), a first bearing (61), and a second bearing (62). The first end cover (4) is located at one end of the stator yoke (1), and the second end cover (5) is located at the other end of the stator yoke (1). The first bearing (61) is mounted on the first end cover (4), and the second bearing (62) is mounted on the second end cover (5). The first bearing (61) and the second bearing (62) are respectively sleeved on the rotor shaft (72).

8. The motor according to claim 6, characterized in that, The flexible member (2) has at least two conductive layers. The stator winding is provided on the conductive layers of the flexible member (2). The conductive layers include a first conductive layer and a second conductive layer. The flexible member (2) includes a substrate. The first conductive layer is located on one side of the substrate, and the second conductive layer is located on the other side of the substrate. The stator winding includes a phase stator winding. The phase stator winding includes a coil. A portion of the same coil is located on the first conductive layer, and another portion of the same coil is located on the second conductive layer. The flexible member (2) includes a first conductive portion that penetrates the substrate. The first conductive portion is electrically connected to the portion of the same coil located on the first conductive layer and the portion located on the second conductive layer.

9. The motor according to claim 8, characterized in that, The winding of one phase includes at least two coils connected in series, and the flexible member (2) includes a second conductive part (26), through which two of the coils of the winding of the same phase are electrically connected.

10. The motor according to claim 9, characterized in that, The second conductive portion (26) is disposed near the center of the substrate (21) relative to the first conductive portion (25). The first conductive portion (25) includes a plurality of first sub-conductive portions (251) and a plurality of second sub-conductive portions (252). The first sub-conductive portions (251) and the second sub-conductive portions (252) are located on opposite sides of the substrate (21). The second conductive portion (26) is located between the first sub-conductive portions (251) and the second sub-conductive portions (252). The coil includes oblique segments. In the same coil, the oblique segment located on the first conductive layer (23) is defined as the first oblique segment, and the oblique segment located on the second conductive layer (24) is defined as the second oblique segment. The first sub-conductive part (251) is electrically connected to the adjacent first oblique segment and the second oblique segment located on one side of the substrate (21), and the second sub-conductive part (252) is electrically connected to the adjacent first oblique segment and the second oblique segment located on the other side of the substrate (21). The first diagonal segment includes multiple first sub-diagonal segments (2211) arranged side by side and multiple second sub-diagonal segments (2212) arranged side by side; The second diagonal segment includes multiple third sub-diagonal segments (2213) arranged side by side and multiple fourth sub-diagonal segments (2214) arranged side by side; The coil includes a vertical segment. In the same coil, the vertical segment located on the first conductive layer (23) is defined as the first vertical segment (2215), and the vertical segment located on the second conductive layer (24) is defined as the second vertical segment (2216). The first vertical segment (2215) is electrically connected to the first sub-oblique segment (2211) and the second sub-oblique segment (2212), and the second vertical segment (2216) is electrically connected to the third sub-oblique segment (2213) and the fourth sub-oblique segment (2214).

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