Stator structure and alternating current motor

Abstract

The invention discloses a stator structure and an AC motor, and relates to the technical field of AC motors, and the stator structure comprises a stator magnet yoke and a flexible circuit board. A cavity with two through ends is formed in the stator magnet yoke; the flexible circuit board is wound and attached to the cavity wall of the cavity, one end of the flexible circuit board is provided with a wiring end used for being connected with an external alternating-current power source, the flexible circuit board at least comprises two conducting layers, a plurality of wires are arranged in each conducting layer, the wires in one conducting layer are electrically connected with the wires in the other conducting layer to form a coil in an enclosing mode, and the coil is arranged in the cavity. The plurality of coils are arranged at intervals along the circumferential direction of the stator magnet yoke and are electrically connected with the wiring terminal; the flexible circuit board is attached to the inner wall of the stator magnet yoke, current passes through the coil and generates a radial magnetic field perpendicular to the stator magnet yoke, and the magnetic field forms a magnetic field loop through the stator magnet yoke. According to the stator winding, the installation of the stator structure can be realized through a fitting mode, and the processing and assembling convenience of the stator structure of the motor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a stator structure and an AC motor. Background Art

[0002] High-performance motors are widely used in scenarios such as robots and medical equipment that have high requirements for motor size and performance. For example, three-phase AC motors, especially permanent magnet AC motors, have become an important technical path for high performance and miniaturization due to their high torque density, high efficiency and good reliability. This type of motor uses the AC current in the stator winding to generate a rotating magnetic field, which interacts with the magnetic field generated by the permanent magnet material on the rotor to generate electromagnetic torque.

[0003] However, for three-phase permanent magnet AC motors, the stator structure includes a stator core and a stator armature winding. Although this design can achieve efficient electromagnetic conversion, the overall structure is relatively complex. This complex stator structure is difficult to process and assemble in small motor applications, making it difficult to achieve large-scale mass production. Summary of the invention

[0004] The main purpose of the present invention is to provide a stator structure and an AC motor, aiming to solve the problem that the processing and assembly of the existing stator structure are relatively difficult.

[0005] To achieve the above-mentioned object, the stator structure proposed in the present invention includes a stator yoke and a flexible circuit board; a cavity with two ends passing through is formed inside the stator yoke; the flexible circuit board is wound and fits against the cavity wall of the cavity, one end of the flexible circuit board is provided with a terminal, the terminal is used to connect an external AC power supply, the flexible circuit board includes at least two conductive layers, each of the conductive layers is provided with a plurality of conductive wires, the conductive wires in one conductive layer are electrically connected to the conductive wires in another conductive layer and enclose a coil, there are a plurality of coils, the plurality of coils are arranged at intervals along the circumferential direction of the stator yoke and connected in series to form a phase winding, and are all electrically connected to the terminal; The flexible circuit board is attached to the inner wall of the stator yoke. Current passes through the coil and generates a radial magnetic field perpendicular to the stator yoke in the air gap of the motor. The magnetic field forms a magnetic field loop using the stator yoke.

[0006] In one embodiment of the present invention, a plurality of groups of the coils are connected in series to form a full-pitch distributed stacked winding; The flexible circuit board comprises a first conductive layer and a second conductive layer, the edges of the first conductive layer and the second conductive layer are both provided with a plurality of conductive through-holes, one of the conductive wires in the first conductive layer is electrically connected to one of the conductive wires in the second conductive layer through the conductive through-holes located at the edge of the flexible circuit board, one of the conductive wires in the second conductive layer is electrically connected to another of the conductive wires in the first conductive layer through the conductive through-holes located at the other edge of the flexible circuit board, another of the conductive wires in the first conductive layer is electrically connected to another of the conductive wires in the second conductive layer through the conductive through-holes located at the edge of the flexible circuit board, and finally a complete full-pitch distributed stacked winding is formed; The plurality of conductive wires in the first conductive layer are alternately connected with the plurality of conductive wires in the second conductive layer in sequence to form a phase of the full-pitch distributed stacked winding.

[0007] In one embodiment of the present invention, the conductive wire comprises at least a first section, a second section and a third section connected in sequence, the second section is parallel to the axial direction of the stator yoke, the first section and the third section are inclined in the same direction relative to the second section, and the multiple conductive wires in each conductive layer are arranged in sequence along the circumferential direction of the stator yoke.

[0008] In one embodiment of the present invention, at least one first segment in the first conductive layer and at least one first segment in the second conductive layer are cross-arranged along a projection perpendicular to the surface of the flexible circuit board; at least one third segment in the first conductive layer and at least one third segment in the second conductive layer are cross-arranged along a projection perpendicular to the surface of the flexible circuit board.

[0009] In one embodiment of the present invention, the plurality of second segments in the first conductive layer and the plurality of second segments in the second conductive layer are evenly arranged along a projection interval perpendicular to the surface of the flexible circuit board, and two ends of the flexible circuit board abut and are wound and adhered to the inner wall of the stator yoke.

[0010] In one embodiment of the present invention, the multiple second segments in the first conductive layer overlap with the multiple second segments in the second conductive layer along the projection portion perpendicular to the surface of the flexible circuit board, or the partial line spacing is small, and the two ends of the flexible circuit board partially overlap and are wound and adhered to the inner wall of the stator yoke.

[0011] In one embodiment of the present invention, the line width of the second segment is greater than the line widths of the first segment and the third segment.

[0012] In one embodiment of the present invention, the shape of the flexible circuit board is a polygon, and the conductive wires are parallel to the adjacent sides of the flexible circuit board; Alternatively, the flexible circuit board is in a rectangular shape, and the conductive wires are at right angles near corners of the flexible circuit board.

[0013] In one embodiment of the present invention, the conductive layer is provided with a midpoint connection hole, and a plurality of conductive wires in the conductive layer are wound to form a three-phase full-pitch distributed stacked winding. The three-phase full-pitch distributed stacked windings are all electrically connected to the midpoint connection hole, and the connection method of the three-phase full-pitch distributed stacked windings is Y-shaped.

[0014] The present invention further provides an AC motor, comprising a rotor and any of the above-mentioned stator structures; the rotor is rotatably disposed in the cavity, and the flexible circuit board surrounds the outer circumference of the rotor.

[0015] The stator structure proposed in the present invention includes a stator yoke and a flexible circuit board. A cylindrical cavity is formed inside the stator yoke. The flexible circuit board includes at least two conductive layers. The flexible circuit board is wound into a cylindrical or tubular shape and adhered to the inner wall of the stator yoke. The flexible circuit board includes at least two conductive layers, and each conductive layer is provided with a plurality of conductive wires. The conductive wires in one conductive layer are electrically connected to the conductive wires in another conductive layer and enclosed to form a coil. There are multiple coils, which are arranged at intervals along the circumference of the stator yoke; at the same time, a terminal is provided at one end of the flexible circuit board, and the coil is electrically connected to an external AC power supply through the terminal. Since the multiple groups of coils on the wound flexible circuit board are arranged at intervals along the circumference of the stator yoke, the changing current will generate a magnetic field, so the multiple groups of coils will generate a magnetic field in the radial direction in the air gap of the motor to drive the rotor to rotate.

[0016] The present application adopts a solution of setting a coil on a flexible circuit board and fitting it to the inner wall of the stator yoke. Compared with the solution of setting the coil in the stator slot of the stator core, the present application can reduce the structural volume occupied by the stator structure. At the same time, there is no need to set the stator slot on the stator yoke. The installation of the stator structure can be achieved only by fitting, which improves the convenience of processing and assembly of the stator structure of the motor. At the same time, the coil is formed by connecting and enclosing the wires in two conductive layers, that is, each of the surrounding wires in the coil is respectively set in two conductive layers. Compared with the solution of setting multiple wires in the coil in the same conductive layer, the present application can also reduce the difficulty of coil production, without the need for complex winding equipment and production process, and improve the production accuracy of the stator structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0018] Figure 1 A schematic structural diagram of an AC motor according to an embodiment of the present invention; Figure 2 for Figure 1 Section view along AA; Figure 3 A schematic structural diagram of another embodiment of the AC motor provided by the present invention; Figure 4 A schematic structural diagram of an embodiment of a flexible circuit board in a stator structure provided by the present invention; Figure 5 for Figure 4 Schematic diagram of the unfolding of the flexible circuit board; Figure 6 for Figure 5 Schematic diagram of the unfolded structure of two conductive layers in a flexible circuit board; Figure 7 for Figure 5 A schematic diagram of the structure of the first winding in the flexible circuit board; Figure 8 for Figure 5 A schematic diagram of the structure of the second winding in the flexible circuit board; Fig. 9 for Figure 5 A schematic diagram of the structure of the third winding in the flexible circuit board; Fig.10 A schematic structural diagram of another embodiment of a flexible circuit board in a stator structure provided by the present invention; Fig.11 for Fig.10 Schematic diagram of the unfolding of the flexible circuit board; Fig.12 for Fig.11 Schematic diagram of the unfolded structure of two conductive layers in a flexible circuit board; Fig.13 for Fig.11 A schematic diagram of the structure of the first winding in the flexible circuit board; Fig.14 for Fig.11 A schematic diagram of the structure of the second winding in the flexible circuit board; Fig.15 for Fig.11 A schematic diagram of the structure of the third winding in the flexible circuit board; Fig.16 for Fig.11 A partial enlarged schematic diagram of one of the windings in the flexible circuit board; Fig.17 It is a schematic diagram of the unfolded structure of another embodiment of the flexible circuit board in the stator structure of the present invention; Fig.18 It is a schematic diagram of the unfolded structure of another embodiment of the flexible circuit board in the stator structure of the present invention.

[0019] Description of Figure Numbers: 1. stator structure; 10. stator yoke; 11. cavity; 20. flexible circuit board; 21. first conductive layer; 22. second conductive layer; 23. wire; 231. first section; 232. second section; 233. third section; 24. coil; 25. conductive perforation; 26. full-pitch distributed stacked winding; 27. midpoint connection hole; 28. terminal; 281. power supply pad; 30. rotor; 40. magnetic field detection component; 41. circuit control board; 42. Hall sensor.

[0020] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0023] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0024] The present invention provides a stator structure 1 .

[0025] Combination Figures 1 to 5As shown, in one embodiment of the present invention, the stator structure 1 includes a stator yoke 10 and a flexible circuit board 20; a cavity 11 with two ends through is formed inside the stator yoke 10; the flexible circuit board 20 is wound and fits with the cavity wall of the cavity 11, and one end of the flexible circuit board 20 is provided with a terminal 28, and the terminal 28 is used to connect an external AC power supply. The flexible circuit board 20 includes at least two conductive layers, and each conductive layer is provided with a plurality of conductive wires 23. The conductive wires 23 in one conductive layer are electrically connected to the conductive wires 23 in another conductive layer and enclose a coil 24. There are multiple coils 24, and the multiple coils 24 are arranged at intervals along the circumference of the stator yoke 10, and are all electrically connected to the terminal 28; The flexible circuit board 20 is attached to the inner wall of the stator yoke 10 . Current passes through the coil 24 and generates a radial magnetic field perpendicular to the stator yoke 10 in the air gap of the motor. The magnetic field forms a magnetic field loop using the stator yoke 10 .

[0026] In this embodiment, the stator structure 1 includes a cylindrical stator yoke 10, in which a cavity 11 is formed with two ends passing through. The stator yoke 10 is made of a soft magnetic material with high magnetic permeability. The selection of this material can significantly improve the magnetic field strength and efficiency of the motor. The stator yoke 10 can be made using a variety of manufacturing processes, such as bonding, welding, or bonding and welding to fix multiple pieces of soft magnetic material together to form a solid overall structure. In addition, the shape of the stator yoke 10 can be designed to different geometric shapes such as cylindrical or polygonal according to actual needs to adapt to different motor application scenarios.

[0027] The flexible circuit board 20 is one of the core components of the present invention, and it is manufactured using FPCB (flexible printed circuit board) technology. The flexible circuit board 20 includes at least two conductive layers, and a plurality of wires 23 are arranged in each conductive layer. These wires 23 are manufactured by precise lamination, photolithography, and etching processes, and have a high degree of accuracy and consistency. In order to prevent a short circuit between the two conductive layers, two insulating layers are arranged in each conductive layer, and a plurality of wires 23 are sandwiched between the two insulating layers. The insulating layer is made of a material that is resistant to high temperatures and has excellent insulation properties, such as polyimide.

[0028] One end of the flexible circuit board 20 is provided with a terminal 28 for connecting to an external AC power source. The design of the terminal 28 needs to consider the stability and reliability of current transmission, so a metal material with good electrical conductivity, such as copper, is usually selected. The terminal 28 can be connected to the external power source by welding, crimping, etc., to ensure that the current can be efficiently transmitted to each coil 24 on the flexible circuit board 20.

[0029] The coil 24 is formed by alternately connecting the wires 23 in two conductive layers. This design not only simplifies the manufacturing process of the coil 24, but also improves the accuracy and stability of the coil 24. Compared with the solution of setting the multiple wires 23 in the coil 24 in the same conductive layer, the coil 24 of the present application is formed by connecting and enclosing the wires 23 in the two conductive layers through the conductive perforations 25 located at the edge of the flexible circuit board 20, that is, the wires 23 each encircled in the coil 24 are respectively arranged in two conductive layers. This method reduces the difficulty of making the coil 24, and does not require complex winding equipment and manufacturing processes, thereby improving the manufacturing accuracy of the stator structure 1. The number and layout of the coil 24 can be adjusted according to the specific needs of the motor, and the multiple coils 24 are evenly spaced and arranged along the circumference of the stator yoke 10 to ensure that the generated magnetic field is evenly distributed. In addition, the rotation direction of the coil 24 can be designed according to the actual application requirements, which can be either clockwise or counterclockwise to meet different magnetic field direction requirements.

[0030] When current passes through the coil 24, a radial magnetic field perpendicular to the stator yoke 10 is generated in the air gap of the motor. This magnetic field forms a closed magnetic field loop with the stator yoke 10, thereby driving the rotor 30 to rotate. In order to further optimize the distribution of the magnetic field, multiple coils 24 are evenly spaced and arranged along the circumference of the stator yoke 10. This layout not only improves the uniformity of the magnetic field, but also reduces the vibration and noise when the motor is running.

[0031] The flexible circuit board 20 can be directly attached to the inner wall of the stator yoke 10, simplifying the installation process. Compared with the traditional solution of placing the coil 24 in the stator slot of the stator core, the design of the present invention greatly reduces the structural volume occupied by the stator winding and improves the convenience of processing and assembly.

[0032] In some embodiments, the flexible circuit board 20 may also integrate a magnetic field detection component 40, such as a Hall sensor 42 and a circuit control board 41. The Hall sensor 42 is used to detect the magnetic field of the rotor 30 when the motor is running, and then detect the angle of the rotor 30. The circuit control board 41 is used to process the data collected by the Hall sensor 42 and feed it back to the control system to achieve precise motor control. This design not only improves the control accuracy of the motor, but also enhances the reliability and stability of the system.

[0033] The present application adopts a flexible circuit board 20 to replace the traditional stator core and stator slot structure, which greatly simplifies the installation process of the stator winding and significantly reduces the structural volume occupied by the stator winding. The flexible circuit board 20 manufactured by high-precision FPCB technology makes the production of the coil 24 easier and more accurate. In addition, the multi-layer conductive layer design of the coil 24 not only improves the uniformity of the magnetic field and the working efficiency of the motor, but also reduces the resistance loss and improves the overall performance of the motor.

[0034] The applicant has made a series of improvements and studies on the slotless stator winding. In some embodiments, it can be considered to set all the wires 23 of the same coil 24 in the same conductive layer, which can also achieve the effect of reducing the structural volume of the stator winding. However, in order to achieve a more uniform rotating magnetic field, there are requirements for the shape, rotation direction, and spacing between the wires of the coil 24. In order to achieve the coil 24 in the same conductive layer, it is necessary to connect it to other windings with connecting holes inside the winding. The processing of the winding is very difficult and the accuracy is difficult to control. At the same time, the concentric coil formed in the same conductive layer has a low ability to generate back electromotive force, which causes a low motor constant. Therefore, the electromagnetic characteristics of this concentric coil are not good. The full-pitch distributed coil in this application can improve the ability of the coil to generate back electromotive force, and the efficiency and torque density of the motor can also be improved.

[0035] In this embodiment, in particular, the coil 24 is configured to be formed by connecting and enclosing the wires 23 in two conductive layers, which reduces the difficulty of making the coil 24 and does not require complicated winding equipment and manufacturing processes, thereby improving the manufacturing accuracy of the stator structure 1. This design is not only suitable for small motors, but also for high-performance motor application scenarios with high space utilization requirements.

[0036] Combination Figures 4 to 8 As shown, in one embodiment of the present invention, multiple groups of coils 24 are connected in series to form a full-pitch distributed stacked winding 26; The flexible circuit board 20 includes a first conductive layer 21 and a second conductive layer 22. The edges of the first conductive layer 21 and the second conductive layer 22 are both provided with a plurality of conductive through-holes 25. A conductive line 23 in the first conductive layer 21 is electrically connected to a conductive line 23 in the second conductive layer 22 through the conductive through-holes 25 located at the edge of the flexible circuit board 20. A conductive line 23 in the second conductive layer 22 is electrically connected to another conductive line 23 in the first conductive layer 21 through the conductive through-holes 25 located at the other edge of the flexible circuit board 20. Another conductive line 23 in the first conductive layer 21 is electrically connected to another conductive line 23 in the second conductive layer 22 through the conductive through-holes 25 located at the edge of the flexible circuit board 20. The plurality of conductive wires 23 in the first conductive layer 21 are alternately connected with the plurality of conductive wires 23 in the second conductive layer 22 in sequence to form a phase-aligned distributed stacked winding 26 .

[0037] In this embodiment, the full-pitch distributed stacked winding 26 can generate a back electromotive force close to a sine wave, which makes the electromagnetic performance of the motor more stable during operation, reduces the influence of high-order harmonics, and thus reduces the loss and noise of the motor. Due to its distributed characteristics, it can effectively weaken the harmonic magnetomotive force and improve the starting performance of the motor. In addition, since the wire 23 in its coil 24 is arranged in two overlapping conductive layers and connected in series through the conductive perforations 25 located at the edge of the flexible circuit board 20 to form a winding, compared with the centralized winding, the formation of the full-pitch distributed stacked winding 26 does not require folding the flexible circuit board 20, which is convenient for process processing and installation.

[0038] Each phase-aligned distributed stacked winding 26 is composed of a plurality of conductors 23, which are distributed in the first conductive layer 21 and the second conductive layer 22 of the flexible circuit board 20 and pass through the conductive through-holes 25 located at the edge of the flexible circuit board 20. The plurality of conductors 23 of the two conductive layers are separated by an insulating layer to prevent short circuits. The conductors 23 are made of highly conductive materials (such as copper or silver) to ensure current transmission efficiency.

[0039] The spacing and shape of the multiple wires 23 located in the first conductive layer 21 are the same, and the spacing and shape of the multiple wires 23 located in the second conductive layer 22 are the same, so only through the above connection method can a full-pitch distributed stacked winding be formed. Compared with the solution of continuously winding to form a coil 24 in the same conductive layer, this embodiment can improve the convenience of processing the full-pitch distributed stacked winding, improve the wiring convenience of each wire 23 in the coil 24, improve the uniformity of the magnetic field generated by the formed full-pitch distributed stacked winding in the circumferential and axial directions of rotation, and can generate back electromotive force with a higher motor constant. The above schemes and effects are all impossible to achieve in the solution of forming a group of coils 24 in the same conductive layer.

[0040] In order to realize the electrical connection between the wires 23 of the two conductive layers, conductive through-holes 25 can be provided on the conductive layers, and the multiple conductive through-holes 25 of each conductive layer overlap each other in the vertical direction. Each conductive through-hole 25 is copper-plated to ensure good conductivity. A wire 23 in the first conductive layer 21 is electrically connected to a wire 23 in the second conductive layer 22 through the conductive through-hole 25, and then another wire 23 in the second conductive layer 22 is electrically connected to another wire 23 in the first conductive layer 21, and so on, until a complete full-pitch distributed stack winding 26 is formed.

[0041] The rotation direction of the coil 24 can be designed according to the actual application requirements, and can be either clockwise or counterclockwise to meet different magnetic field direction requirements. While the multiple wires 23 in the full-pitch distributed stack winding 26 are sequentially connected between the two conductive layers, the multiple groups of coils 24 are extended along the circumference of the stator yoke 10 as a whole, and the multiple coils 24 are also extended along the circumference of the stator yoke 10 to ensure uniform magnetic field distribution.

[0042] In this embodiment, the coil 24 is formed by alternately connecting the wires 23 in two conductive layers through the conductive through-holes 25 located at the edge of the flexible circuit board 20. Compared with the method of centrally arranging all the wires 23 in the same conductive layer, this method reduces the difficulty of manufacturing the coil 24, does not require complex winding equipment and manufacturing processes, and thus improves the manufacturing accuracy of the stator structure 1. At the same time, the arrangement and winding of the wires 23 in the coil 24 are more uniform, so that the magnetic field distribution formed is also more uniform.

[0043] In addition, the wire 23 can have different shapes, such as straight, polygonal or arc, to adapt to different application scenarios. In some high-power motors, a thicker wire 23 cross-section can be selected to reduce resistance loss and improve the overall efficiency of the motor.

[0044] Combination Figure 4 and Figure 8 As shown, in one embodiment of the present invention, the wire 23 includes at least a first section 231, a second section 232 and a third section 233 which are connected in sequence, the second section 232 is parallel to the axial direction of the stator yoke 10, the first section 231 and the third section 233 are both inclined in the same direction relative to the second section 232, and the multiple wires 23 in each conductive layer are arranged in sequence along the circumferential direction of the stator yoke 10.

[0045] In this embodiment, the conductor 23 adopts a multi-section design. The second section 232 is parallel to the axial direction of the stator yoke 10, while the first section 231 and the third section 233 are relatively inclined, and at the same time, the magnetic field of the full-pitch distributed stacked winding 26 formed by the combination of multiple conductors 23 is more uniform. Since the conductor 23 of each conductive layer is formed by connecting the first section 231, the second section 232 and the third section 233, and in the same coil 24, the inclination angle of the first section 231 and the third section 233 can be set to the same as that of the second section 232, so as to facilitate the winding process of the conductor 23.

[0046] like Figure 5 and Figure 6As shown, the multiple wires 23 in each conductive layer are arranged at intervals along the circumference of the stator yoke 10, and the structures of the wires 23 in each conductive layer are designed to be the same and are evenly spaced, and the wires in the two conductive layers are symmetrically arranged, so that after a wire 23 in one conductive layer is connected to another wire 23 in another conductive layer, a coil 24 structure with a diamond shape is formed, so that after the coil 24 is energized, the changing current forms a magnetic field in the radial direction of the stator yoke 10.

[0047] The inclination angles of the first section 231 and the third section 233 in the wire 23 compared to the second section 232 can be adjusted according to actual needs to optimize the magnetic field distribution and reduce the heat accumulation in the current density concentration area. For example, in a high-power motor, a proper inclination angle can improve the heat dissipation performance and reduce the vibration and noise when the motor is running.

[0048] It is understandable that, since the present application sets the wires in the coil in the first conductive layer and the second conductive layer respectively, it is convenient to change the shape and angle of the wires in the first conductive layer and the second conductive layer according to the needs, thereby realizing the formation of coils of different shapes and sizes. Compared with the scheme of forming a coil in the same conductive layer, this design scheme of the present application can significantly improve the ability to form the back electromotive force of the motor coil and improve the electromagnetic characteristics of the winding. At the same time, the winding of the wire is also relatively easy to achieve.

[0049] Combination Figures 6 to 8 As shown, in one embodiment of the present invention, at least one first segment 231 in the first conductive layer 21 and at least one first segment 231 in the second conductive layer 22 are cross-arranged along a projection perpendicular to the surface of the flexible circuit board 20; at least one third segment 233 in the first conductive layer 21 and at least one third segment 233 in the second conductive layer 22 are cross-arranged along a projection perpendicular to the surface of the flexible circuit board 20.

[0050] In this embodiment, since an insulating layer is provided between the wires 23 in the two conductive layers, although the third segment 233 in the first conductive layer 21 and the third segment 233 in the second conductive layer 22 are arranged crosswise along the projection perpendicular to the surface of the flexible circuit board 20, a short circuit between the wires 23 will not be caused. In addition, this structural design makes the coil 24 formed as Figures 6 to 8 As shown, the coil 24 is extended along the circumference of the stator yoke 10 while rotating clockwise or counterclockwise. Therefore, when the flexible circuit board 20 is wound and attached to the inner wall of the stator yoke 10, the magnetic field formed is more evenly distributed along the circumference of the stator yoke 10. In other embodiments, the full-pitch distributed stacked winding 26 can also be provided with multiple wires 23 connected and rotated along the same center.

[0051] Combination Figures 3 to 8As shown, in one embodiment of the present invention, a plurality of second segments 232 in the first conductive layer 21 and a plurality of second segments 232 in the second conductive layer 22 are evenly arranged along a projection interval perpendicular to the surface of the flexible circuit board 20, and both ends of the flexible circuit board 20 are abutted and wound to fit the inner wall of the stator yoke 10.

[0052] In this embodiment, the plurality of second segments 232 in the first conductive layer 21 and the plurality of second segments 232 in the second conductive layer 22 are evenly spaced and arranged on a projection perpendicular to the surface of the flexible circuit board 20. This even arrangement ensures that the current is evenly distributed between the two conductive layers, enhances the uniformity and strength of the magnetic field, and reduces vibration and noise problems. At the same time, this evenly spaced arrangement of the second segments 232 makes the magnetic field evenly distributed in the circumferential direction of the stator yoke 10, so that the two ends of the flexible circuit board 20 are abutted and wound to fit the inner wall of the stator yoke 10, so that the second segments 232 in the flexible circuit board 20 are spaced and distributed along the circumferential direction of the stator yoke 10, thereby improving the uniformity of the magnetic field distribution.

[0053] Combination Figures 9 to 15 As shown, in one embodiment of the present invention, a plurality of second segments 232 in the first conductive layer 21 overlap with a plurality of second segments 232 in the second conductive layer 22 along a projection portion perpendicular to the surface of the flexible circuit board 20, or a partial line spacing is small, and the two ends of the flexible circuit board 20 partially overlap and are wound and adhered to the inner wall of the stator yoke 10.

[0054] In this embodiment, if Fig.10 As shown, the area occupied by the multiple second segments 232 in the second conductive layer 22 partially overlaps with the area occupied by the multiple second segments 232 in the first conductive layer 21. In the overlapping area, the multiple second segments 232 in the first conductive layer 21 can overlap with the multiple second segments 232 in the second conductive layer 22 in the projection perpendicular to the surface of the flexible circuit board 20, or can be arranged at intervals. It can be understood that in the overlapping area, the interval between the second segment 232 in the first conductive layer 21 and the second segment 232 in the adjacent second conductive layer 22 is small, so the magnetic field strength here is higher. This design increases the current density and enhances the local magnetic field strength.

[0055] Furthermore, the two ends of the flexible circuit board 20 are partially overlapped and wound to fit the inner wall of the stator yoke 10. Fig. 9As shown, the overlapping portion of the two ends of the flexible circuit board 20 is the portion where the multiple second segments 232 are evenly spaced after the first conductive layer 21 and the second conductive layer 22 overlap. Therefore, when the two ends of the flexible circuit board 20 overlap and are wound, the second segments 232, which originally had a larger spacing and a smaller density, have a smaller spacing and a larger density due to the winding overlap of the flexible circuit board 20. The portion of the flexible circuit board 20 that does not overlap after winding has a smaller spacing and a larger density. Through the above-mentioned structural design and winding method, the magnetic field formed by the flexible circuit board 20 is more evenly distributed in the circumferential direction of the stator yoke 10, and the magnetic field strength is higher. This design is particularly suitable for application scenarios with high requirements for magnetic field strength and motor efficiency, which significantly improves the strength and uniformity of the magnetic field and reduces vibration and noise during operation.

[0056] In one embodiment of the present invention, the line width of the second segment 232 is greater than the line widths of the first segment 231 and the third segment 233 .

[0057] In this embodiment, the second section 232 is parallel to the axial direction of the stator yoke 10, and its line width is greater than the line width of the first section 231 and the third section 233. This design reduces resistance loss, improves current transmission efficiency, and reduces the risk of local heating. The wider second section 232 helps optimize the current path, so that the current is more evenly distributed between the two conductive layers, enhances the uniformity and strength of the magnetic field, and improves the heat dissipation performance of the motor. In addition, combined with Figures 6 to 8 As shown, compared with the first segment 231 and the third segment 233 , the spacing between the plurality of second segments 232 is larger, and the wider spacing facilitates the processing of the second segments 232 with wider line widths.

[0058] Combination Figures 4 to 8 as well as Figures 10 to 15 As shown, in one embodiment of the present invention, the shape of the flexible circuit board 20 is a polygon, and the conductors 23 are parallel to the sides of the adjacent flexible circuit boards 20; or, combined with Fig.16 and Fig.17 As shown, the flexible circuit board 20 is rectangular in shape, and the conductors 23 are at right angles near the corners of the flexible circuit board 20 .

[0059] In this embodiment, the flexible circuit board 20 can be hexagonal, octagonal, etc. When the flexible circuit board 20 is polygonal, the wire 23 is parallel to the side of the adjacent flexible circuit board 20. This design allows the wire 23 to better fit the inner wall of the stator yoke 10 during the winding process and optimize the magnetic field distribution. The polygonal design provides more flexibility and is suitable for stator yokes 10 of different shapes and sizes, improving the convenience of installation and assembly.

[0060] In another embodiment, when the flexible circuit board 20 is rectangular, the wire 23 is at a right angle near the corners, so that the wire 23 located at the edge of the flexible circuit board 20 is more adapted to the shape of the flexible circuit board 20, thereby increasing the number and density of wiring on the surface of the flexible circuit board 20. At the same time, when the flexible circuit board 20 is wound on the inner wall of the stator yoke 10, the magnetic field generated by the flexible circuit board 20 can be made more uniform in the circumferential and axial directions of the stator yoke 10, so as to make full use of the space of the rectangular flexible circuit board 20.

[0061] Combination Figures 4 to 8 as well as Figures 10 to 17 As shown, in one embodiment of the present invention, a plurality of conductive through-holes 25 are provided in the conductive layer, at least two conductive layers are overlapped, and the plurality of conductive through-holes 25 in one conductive layer are overlapped with the plurality of conductive through-holes 25 in the other conductive layers in a direction perpendicular to the conductive layers, and the two conductive wires 23 of each coil 24 are electrically connected through the conductive through-holes 25. These conductive through-holes 25 overlap with each other in a direction perpendicular to the conductive layers to achieve electrical connection between different conductive layers.

[0062] In this embodiment, each conductive layer is provided with a plurality of conductive through-holes 25, and the positions of these through-holes are precisely aligned to ensure that the wires 23 on different conductive layers can be electrically connected through the through-holes. The conductive through-holes 25 are copper plated to ensure good conductivity and mechanical strength.

[0063] At least two conductive layers are stacked, and the multiple conductive through-holes 25 of each conductive layer overlap each other in the vertical direction. This design allows the current to be smoothly transmitted between different conductive layers to form a complete current path. The two wires 23 of different layers in the coil 24 are electrically connected through the conductive through-holes 25.

[0064] In addition, combined Figures 4 to 8 as well as Figures 10 to 17 As shown, the terminal 28 is provided with three power supply pads 281, and the plurality of coils 24 are electrically connected to the three power supply pads 281 respectively to form three full-pitch distributed stacked windings 26. The three full-pitch distributed stacked windings 26 are combined to form a three-phase winding with an electrical angle difference of 120 degrees or 240 degrees.

[0065] The terminal 28 is provided with an interface for connecting an external AC power source and includes three power supply pads 281 (e.g., A, B, and C). Each power supply pad 281 is connected to a group of coils 24 to form an independent full-pitch distributed stacked winding 26. This design simplifies the connection of an external power source and ensures that each phase full-pitch distributed stacked winding 26 can be powered independently.

[0066] The flexible circuit board 20 is also provided with a power supply through-hole, which is located between the coil 24 and the power supply pad 281. The coil 24 in each full-pitch distributed stacked winding 26 is electrically connected to the corresponding power supply pad 281 through the power supply through-hole. Multiple full-pitch distributed stacked windings 26 are evenly distributed in the circumferential direction of the stator yoke 10 to ensure the uniformity and stability of the magnetic field. The electrical angle difference between the full-pitch distributed stacked windings 26 is 120 degrees or 240 degrees. At the same time, the straight line portion of the coil 24 of each phase full-pitch distributed stacked winding 26, that is, all the second segments 232, has a width of 60 degrees electrical angle in the first conductive layer 21 and the second conductive layer 22.

[0067] When an external AC power source is connected to the three power supply pads 281 of the terminal 28, the current flows through the three full-pitch distributed stacked windings 26 respectively to generate a rotating magnetic field. Since there is an electrical angle difference of 120 degrees or 240 degrees between the three full-pitch distributed stacked windings 26, the generated magnetic field will form a stable rotating magnetic field in the air gap of the motor. This rotating magnetic field interacts with the permanent magnets on the rotor 30 to generate electromagnetic torque and drive the motor to operate. The design of the three-phase full-pitch distributed stacked windings 26 allows the current to be transmitted smoothly between different conductive layers, enhancing the uniformity and strength of the magnetic field. This design is particularly suitable for high-performance three-phase AC motors, such as robots, medical equipment and other fields. The three-phase full-pitch distributed stacked windings 26 can significantly improve the torque density and efficiency of the motor and reduce vibration and noise during operation.

[0068] In other embodiments, the full-pitch distributed stacked winding 26 may also be in the form of single-phase, two-phase or other multi-phase forms.

[0069] In one embodiment of the present invention, a midpoint connection hole 27 is opened in the conductive layer, and multiple wires in the conductive layer are connected in series to form a three-phase full-pitch distributed stacked winding 26. The three-phase full-pitch distributed stacked winding 26 are all electrically connected to the midpoint connection hole 27, and the connection method of the three-phase full-pitch distributed stacked winding 26 is Y-shaped.

[0070] The connection mode of the three-phase full-pitch distributed stacked windings 26 is Y-shaped (star-shaped), that is, one end of each full-pitch distributed stacked winding 26 is respectively connected to a power supply pad 281 (such as A, B, C), and the other end is commonly connected to a midpoint (neutral point). This connection mode makes the electrical angle difference between each full-pitch distributed stacked winding 26 120 degrees, forming a standard three-phase AC motor winding structure.

[0071] A midpoint connection hole 27 is provided on the surface of the flexible circuit board 20 for connecting the common ends of the three full-pitch distributed stacked windings 26 together. The midpoint connection hole 27 is located at the center of the flexible circuit board 20, and can also be provided on the side of the flexible circuit board 20 close to the terminal 28. The midpoint connection hole 27 is copper-plated to ensure good conductivity and mechanical strength. One end of each phase full-pitch distributed stacked winding 26 is electrically connected to the corresponding power supply pad 281 through the conductive through hole 25, and the other end is connected to the midpoint connection hole 27 through the wire 23. This design ensures that the current is evenly distributed between each full-pitch distributed stacked winding 26, and forms a stable Y-shaped connection.

[0072] In one embodiment of the present invention, the stator structure 1 further includes a magnetic field detection component 40 , and the magnetic field detection component 40 includes a circuit control board 41 and a Hall sensor 42 .

[0073] The Hall sensor 42 is arranged on the circuit control board 41, and the circuit control board 41 is connected to the side of the flexible circuit board 20 where the terminal 28 is provided. The flexible circuit board 20 is wound to form a cylindrical stator winding, and the circuit control board 41 is in the shape of a circular ring. After the flexible circuit board 20 is wound to form a cylindrical stator winding, the circuit control board 41 is arranged in a cover shape at the opening of the stator winding. A positioning groove is provided on the outer periphery of the circuit control board 41, and a positioning tooth is provided at the opening of the stator winding, and the positioning tooth is limited in the positioning groove; the Hall sensor 42 is used to detect the magnetic field of the rotor 30 when the motor is running, and then detect the angle of the rotor 30.

[0074] In one embodiment, the circuit control board 41 is also flexible, so that the circuit control board 41 can be folded and covered at the opening of the stator winding. The circuit control board 41 is set on the side of the flexible circuit board 20 close to the terminal 28, so that the circuit control board 41 is electrically connected to the external power supply through the terminal 28. In addition to the pins for the positive pole of the power supply, the ground and the signal output, the Hall sensor 42 is also provided with pins for the control signal and the speed signal. Therefore, the Hall sensor 42 needs to be connected to multiple external connection lines. By designing the circuit control board 41 to be flexible, the circuit control board 41 and the flexible circuit board 20 can be integrated together during processing, so that the Hall sensor 42 can be electrically connected to the external circuit through the terminal 28, which greatly improves the space utilization of the motor, reduces the structural volume, and improves the convenience of wiring.

[0075] There are multiple Hall sensors 42, which are arranged at intervals along the circumference of the circuit control board 41 to improve the detection accuracy of the magnetic field of different positions of the rotor 30 by the magnetic field detection component 40. A plurality of positioning grooves are provided on the outer circumference of the annular circuit control board 41, and a plurality of positioning teeth are convexly provided on one side of the flexible circuit board 20. The plurality of positioning teeth and the circuit control board 41 are located on the same side of the flexible circuit board 20. When the circuit control board 41 is covered at the opening of the stator winding, each positioning tooth fits with the positioning groove of the circuit control board 41, so that the circuit control board 41 is accurately installed on the stator winding, thereby improving the accuracy and stability of the Hall sensor 42 in detecting the magnetic field of the rotor 30 when the motor is running.

[0076] The stator windings described above are three-phase systems with Y-type connections, which can also be realized with triangle connections ( Fig.17 The triangle connection mode of the stator winding is shown. The number of magnetic pole pairs of the full-pitch distributed stacked winding 26 introduced is 1, and of course it can be extended to other numbers of magnetic pole pairs. The number of turns of the full-pitch distributed stacked winding 26 can also exceed 2 turns in part or in whole to increase the number of turns of the full-pitch distributed stacked winding 26. The number of conductive layers in the flexible circuit board 20 can be more than 2 layers. Similarly, the formation mode of the full-pitch distributed stacked winding 26 can also realize single-phase, two-phase, or other multi-phase forms.

[0077] The present invention also proposes an AC motor, which includes a rotor and a stator structure. The specific structure of the stator structure refers to the above-mentioned embodiment. Since the AC motor adopts all the technical solutions of all the above-mentioned embodiments of the stator structure, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0078] The rotor is rotatably disposed in the cavity, and the flexible circuit board surrounds the outer circumference of the rotor. The rotor is disposed in the cavity formed inside the stator yoke and can rotate freely. The rotor can be a permanent magnet rotor or an induction rotor, depending on the application requirements.

[0079] The flexible circuit board surrounds the outer circumference of the rotor, allowing the magnetic field generated by the stator winding to act efficiently on the rotor. This design not only simplifies the installation process, but also reduces the structural volume occupied by the stator winding, and improves the convenience of processing and assembly.

[0080] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A stator structure, characterized in that: The stator structure comprises: a stator yoke, wherein a cavity with two ends penetrating therein is formed; and A flexible circuit board, the flexible circuit board is wound and fits with the cavity wall of the cavity, one end of the flexible circuit board is provided with a terminal, the terminal is used to connect to an external AC power source, the flexible circuit board includes at least two conductive layers, each conductive layer is provided with a plurality of conductive wires, the conductive wires in one conductive layer are electrically connected to the conductive wires in another conductive layer and enclose a coil, there are a plurality of coils, the plurality of coils are arranged at intervals along the circumferential direction of the stator yoke, and are all electrically connected to the terminal; The flexible circuit board is attached to the inner wall of the stator yoke. Current passes through the coil and generates a radial magnetic field perpendicular to the stator yoke in the air gap of the motor. The magnetic field forms a magnetic field loop using the stator yoke.

2. The stator structure according to claim 1, characterized in that: Multiple groups of coils are connected in series to form a full-pitch distributed stacked winding; The flexible circuit board comprises a first conductive layer and a second conductive layer, the edges of the first conductive layer and the second conductive layer are both provided with a plurality of conductive through-holes, one of the conductive wires in the first conductive layer is electrically connected to one of the conductive wires in the second conductive layer through the conductive through-holes located at the edge of the flexible circuit board, one of the conductive wires in the second conductive layer is electrically connected to another of the conductive wires in the first conductive layer through the conductive through-holes located at the other edge of the flexible circuit board, another of the conductive wires in the first conductive layer is electrically connected to another of the conductive wires in the second conductive layer through the conductive through-holes located at the edge of the flexible circuit board, and finally a complete full-pitch distributed stacked winding is formed; The plurality of conductive wires in the first conductive layer are alternately connected with the plurality of conductive wires in the second conductive layer in sequence to form a phase of the full-pitch distributed stacked winding.

3. The stator structure according to claim 2, characterized in that: The conductive wire at least includes a first section, a second section, and a third section connected in sequence, the second section is parallel to the axial direction of the stator yoke, the first section and the third section are both inclined in the same direction relative to the second section, and the multiple conductive wires in each conductive layer are arranged in sequence along the circumferential direction of the stator yoke.

4. The stator structure according to claim 3, characterized in that: At least one first segment in the first conductive layer and at least one first segment in the second conductive layer are intersected along a projection perpendicular to the surface of the flexible circuit board; at least one third segment in the first conductive layer and at least one third segment in the second conductive layer are intersected along a projection perpendicular to the surface of the flexible circuit board.

5. The stator structure according to claim 4, characterized in that: The multiple second segments in the first conductive layer and the multiple second segments in the second conductive layer are evenly arranged along a projection interval perpendicular to the surface of the flexible circuit board, and two ends of the flexible circuit board abut and are wound and adhered to the inner wall of the stator yoke.

6. The stator structure according to claim 4, characterized in that: The multiple second segments in the first conductive layer overlap with the multiple second segments in the second conductive layer along the projection part perpendicular to the surface of the flexible circuit board, or the partial line spacing is small, and the two ends of the flexible circuit board partially overlap and are wound and adhered to the inner wall of the stator yoke.

7. The stator structure according to any one of claims 3 to 6, characterized in that: The line width of the second segment is greater than the line widths of the first segment and the third segment.

8. The stator structure according to any one of claims 3 to 6, characterized in that: The flexible circuit board is in a polygonal shape, and the conductive wires are parallel to the adjacent sides of the flexible circuit board; Alternatively, the flexible circuit board is in a rectangular shape, and the conductive wires are at right angles near the corners of the flexible circuit board, so as to fully utilize the space of the rectangular flexible circuit board.

9. The stator structure according to any one of claims 1 to 6, characterized in that: The conductive layer is provided with a midpoint connection hole, and multiple wires in the conductive layer are connected in series to form a three-phase full-pitch distributed stacked winding. The three-phase full-pitch distributed stacked windings are all electrically connected to the midpoint connection hole, and the connection method of the three-phase full-pitch distributed stacked windings is Y-shaped.

10. An AC motor, characterized in that: The AC motor comprises a rotor and a stator structure as claimed in any one of claims 1 to 9; the rotor is rotatably disposed in the cavity, and the flexible circuit board surrounds the outer circumference of the rotor.

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