Novel miniature motor with yoke-free stator

Abstract

The invention relates to a novel micro motor with a yoke-free stator. The technical problem that a stator of an existing traditional micro motor has defects and the like is solved. Comprising a motor shell and a controller shell arranged at one end of the motor shell, a motor shaft with a motor rotor on the outer side is rotationally arranged in the motor shell in a penetrating mode, a yoke-free stator located on the outer side of the motor rotor in the circumferential direction is arranged on the inner side of the motor shell, and a plurality of stator tooth parts are arranged on the outer side of the yoke-free stator in the circumferential direction. Tooth grooves are formed in the stator tooth parts, a stator groove is formed between every two adjacent stator tooth parts, and a through groove structure communicated with the inner side of the yoke-free stator is arranged at the bottom of each stator groove. The invention has the advantages that: a yoke part required by a magnetic flux loop in a traditional stator is thoroughly removed by utilizing the design of the yoke-free stator, eddy current and magnetic hysteresis loss are radically reduced, the efficiency is particularly obviously improved at a high rotating speed, the temperature rise of the motor is lower, and the motor is lighter and smaller and realizes extremely high power density under the condition of outputting the same power.

Description

Technical Field

[0001] This invention belongs to the field of micro motor equipment technology, specifically relating to a novel micro motor without a yoke stator. Background Technology

[0002] Traditional micro motors typically feature a complete yoke structure in their stators. While this structure provides support for the stator teeth and guides magnetic flux, it also presents significant drawbacks. During high-speed operation, the alternating magnetic field in the stator yoke generates substantial eddy current and hysteresis losses, resulting in wasted energy and reduced operating efficiency. Furthermore, these losses are directly converted into heat, further reducing efficiency and exacerbating temperature rise. The yoke also adds to the stator's volume and weight, reducing power density and contradicting the trend towards lightweight micro motors. Additionally, the yoke compresses the effective space of the stator slots, affecting the optimal winding arrangement and ultimately limiting torque output. Summary of the Invention

[0003] The purpose of this invention is to address the above-mentioned problems by providing a novel micro motor without a yoke stator.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a novel yokeless stator micro motor, comprising a motor housing and a controller housing disposed at one end of the motor housing, wherein a motor shaft with a motor rotor on its outer side is rotatably inserted inside the motor housing, and a yokeless stator is disposed on the inner side of the motor housing located circumferentially outside the motor rotor. The yokeless stator has a plurality of circumferentially arranged stator teeth on its outer side, each stator tooth having an axially extending and vertically penetrating tooth groove, with a stator slot formed between adjacent stator teeth, and a through-slot structure communicating with the inner side of the yokeless stator at the bottom of the stator slot. This eliminates the heavy stator yoke found in traditional motors, significantly reducing eddy current losses and hysteresis losses caused by magnetic flux changes, and improving motor efficiency, especially at high speeds. It provides a key structural foundation for motor miniaturization and lightweighting, conforming to the development trend of micro motors, and can output greater power within the same volume or weight.

[0005] In the aforementioned novel yokeless stator micro motor, the slot extends axially from one end of the stator teeth to the other end. One side of the slot penetrates the upper side of the stator teeth, and the other side is connected to the inner side of the yokeless stator. This axially penetrating slot allows the winding to be easily inserted into the slot from the inner side of the stator, simplifying the winding process. It is particularly suitable for automated production, improving production efficiency and consistency.

[0006] In the aforementioned novel yokeless stator micro motor, the stator slots have a structure that is wider at the top and narrower at the bottom, with both ends of the slots extending to both ends of the yokeless stator. The wide slot area can accommodate more windings, thereby improving the motor's torque and power output.

[0007] In the aforementioned novel yokeless stator micro motor, the through-slot structure includes a plurality of through-slot bodies evenly and sequentially arranged at equal intervals at the bottom of the stator slots, and each of the through-slot bodies is connected to the inner side of the yokeless stator. During motor operation, air can flow between the inner side of the stator and the stator slots, effectively carrying away the heat generated by the windings and core, preventing overheating, and improving the motor's continuous operating capacity and reliability.

[0008] In the aforementioned novel yokeless stator micro motor, the yokeless stator includes a stator cylindrical section formed by several circumferentially evenly distributed stator frames. Each end of the stator cylindrical section has a stator end cap that connects to the ends of each stator frame and matches the shape of the stator cylindrical section. The stator end cap has a central hole through which the motor rotor passes. The central hole is designed to increase torque and reduce magnetic leakage.

[0009] In the aforementioned novel yokeless stator micro motor, the stator frame has an inwardly concave curved cross-section, and the stator slots are formed on the outer side of each stator frame. Stator teeth are formed between adjacent stator frames and stator end caps, with the tooth slots formed between corresponding sides of the two adjacent stator frames. The individual stator frame structure is simple and can be mass-produced using efficient processes such as stamping and etching, then assembled into a complete stator. This reduces the processing difficulty and cost of complex components. Simultaneously, the stator end caps at both ends fix the stator frames together, forming a robust cylindrical whole, ensuring the mechanical strength of the structure.

[0010] In the aforementioned novel yokeless stator micro motor, the stator frame includes two symmetrically arranged first inclined portions that are inclined in opposite directions. Each of the first inclined portions has a second inclined portion on one side, and the corresponding sides of the second inclined portions are connected by a horizontal portion. The toothed slots are formed between the first inclined portions of two adjacent stator frames, and the through slots are arranged at equal intervals on the horizontal portion, with a partition formed between two adjacent through slots.

[0011] In the aforementioned novel yokeless stator micro motor, a 130-degree angle is formed between the first inclined portion and the second inclined portion, and a 170-degree angle is formed between the second inclined portion and the horizontal portion. The 130° angle allows the first inclined portion to more effectively guide the magnetic lines of force toward the rotor, reducing magnetic flux leakage and improving electromagnetic torque. The 170° angle and the design of the horizontal portion enable the bottom of the stator frame to stably bear the electromagnetic force from the windings and evenly distribute the stress. At the same time, this curved structure itself has better resistance to deformation, and the space between the two first inclined portions naturally forms the slots for placing the windings.

[0012] In the aforementioned novel yokeless stator micro motor, one end of the motor shaft extends out of the motor housing and forms an output section at the end away from the controller housing, while the other end of the motor shaft extends into the controller housing and forms a sensing section corresponding to the circuit board located inside the controller housing. The circuit board is connected to a wire extending from the end of the controller housing away from the motor housing.

[0013] In the aforementioned novel yokeless stator micro motor, the controller housing has a wire clamping block on the outer side near the conductor end, which contacts the conductor, and the wire clamping block is connected to the controller housing by a fixing bolt.

[0014] Compared with existing technologies, the advantages of this invention are as follows.

[0015] 1. This device utilizes a yokeless stator design, completely eliminating the yoke required for the magnetic flux loop in a traditional stator. This reduces eddy current and hysteresis losses at the source, resulting in a significant efficiency improvement, especially at high speeds. The motor also experiences lower temperature rise and is lighter and smaller while outputting the same power, achieving extremely high power density.

[0016] 2. The device has through slots at the bottom of the stator slots that connect to the inside of the motor. The heat generated by the motor can be efficiently carried away by air convection through these through slots, solving the heat dissipation problem that micro motors generally face due to their limited space, and ensuring the motor's continuous high power output and long service life.

[0017] 3. This device decomposes the complex stator into multiple identical stator frames and two stator end caps. The simple structure of a single stator frame is suitable for low-cost, high-precision mass production processes such as stamping and etching. At the same time, the axially penetrating slots and open structure allow winding from the inside of the stator or direct embedding of prefabricated windings, which can easily achieve automated production, greatly improve production efficiency, consistency and slot fill factor, thereby reducing manufacturing costs. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention.

[0019] Figure 2 This is a structural cross-sectional view of the present invention.

[0020] Figure 3 This is a schematic diagram of the interior of the motor housing in this invention.

[0021] Figure 4 This is a schematic diagram of the stator without a yoke in this invention.

[0022] Figure 5 This is a cross-sectional view of the stator without a yoke in this invention.

[0023] In the diagram: Motor housing 1, Controller housing 11, Circuit board 12, Wire 13, Wire clamp 14, Fixing bolt 15, Motor shaft 2, Motor rotor 21, Stator without yoke 22, Stator teeth 23, Tooth groove 24, Stator slot 25, Stator frame 26, Stator cylindrical part 27, Stator end cover 28, Center hole 29, Through slot structure 3, Through slot body 31, First inclined part 4, Second inclined part 41, Horizontal part 42, Separator part 43, Output part 44, Sensing part 45. Detailed Implementation

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0025] like Figure 1-5 As shown, a novel yokeless stator micro motor includes a motor housing 1 and a controller housing 11 disposed at one end of the motor housing 1. A motor shaft 2 with a motor rotor 21 rotatably passing through the motor housing 1 is disposed inside the motor housing 1. A yokeless stator 22 is disposed on the inner side of the motor housing 1, circumferentially outside the motor rotor 21. The yokeless stator 22 has several circumferentially arranged stator teeth 23 on its outer side. Each stator tooth 23 has an axially extending groove 24 that vertically penetrates the stator tooth 23. A stator slot 25 is formed between two adjacent stator teeth 23. The bottom of the stator slot 25 has a through-slot structure 3 communicating with the inner side of the yokeless stator 22. This design eliminates the heavy stator yoke found in traditional motors, significantly reducing eddy current losses and hysteresis losses caused by magnetic flux changes, thus improving motor efficiency, especially at high speeds. It provides a key structural foundation for motor miniaturization and weight reduction, aligning with the development trend of micro motors, and can output greater power within the same volume or weight.

[0026] like Figure 3 As shown, the slot 24 extends axially from one end of the stator tooth portion 23 to the other end. One side of the slot 24 penetrates the upper side of the stator tooth portion 23, and the other side is connected to the inner side of the stator 22 without a yoke. This axially penetrating slot 24 allows the winding to be easily inserted into the slot from the inside of the stator, which simplifies the winding process, is particularly suitable for automated production, and can improve production efficiency and consistency.

[0027] The stator slot 25 has a structure that is wider at the top and narrower at the bottom, and both ends of the stator slot 25 extend to both ends of the yokeless stator 22. The wide slot area can accommodate more windings, thereby improving the torque and power output of the motor.

[0028] Specifically, the through-slot structure 3 includes several through-slot bodies 31 evenly spaced at the bottom of the stator slot 25, and each through-slot body 31 is connected to the inner side of the stator 22 without yoke. When the motor is running, air can flow between the inner side of the stator and the stator slot 25, effectively carrying away the heat generated by the windings and the iron core, preventing the motor from overheating, and improving the motor's continuous working capacity and reliability.

[0029] Combination Figures 2-5 As shown, the yokeless stator 22 includes a stator cylindrical portion 27 formed by a plurality of circumferentially evenly distributed stator frames 26. Both ends of the stator cylindrical portion 27 are provided with stator end caps 28 that connect to the ends of each stator frame 26 and match the shape of the stator cylindrical portion 27. The stator end caps 28 have a central hole 29 through which the motor rotor 21 passes. The central hole 29 is for increasing torque and reducing magnetic leakage.

[0030] The stator frame 26 has an inwardly concave curved cross-section, and stator slots 25 are formed on the outer side of each stator frame 26. Stator teeth 23 are formed between two adjacent stator frames 26 and the stator end caps 28, with tooth grooves 24 formed between corresponding sides of the two adjacent stator frames 26. The individual stator frame 26 has a simple structure and can be mass-produced using efficient processes such as stamping and etching, then assembled into a complete stator. This reduces the processing difficulty and cost of complex components. Simultaneously, the stator end caps 28 at both ends fix the stator frames 26 together, forming a robust cylindrical whole, ensuring the mechanical strength of the structure.

[0031] Specifically, the stator frame 26 includes two symmetrically arranged first inclined portions 4 that are inclined in opposite directions. Each first inclined portion 4 has a second inclined portion 41 on one side, and the corresponding sides of the second inclined portions 41 are connected by a horizontal portion 42. Gear grooves 24 are formed between the first inclined portions 4 of two adjacent stator frames 26, and through slots 31 are arranged at equal intervals on the horizontal portion 42, with a partition 43 formed between two adjacent through slots 31.

[0032] Meanwhile, a 130-degree angle is formed between the first inclined portion 4 and the second inclined portion 41, and a 170-degree angle is formed between the second inclined portion 41 and the horizontal portion 42. The 130-degree angle allows the first inclined portion 4 to more effectively guide the magnetic lines of force toward the rotor, reducing magnetic flux leakage and increasing electromagnetic torque. The 170-degree angle and the design of the horizontal portion 42 enable the bottom of the stator frame 26 to stably bear the electromagnetic force from the windings and distribute the stress evenly. At the same time, this curved structure itself has better resistance to deformation, and the space between the two first inclined portions 4 naturally forms the slots 24 for placing the windings.

[0033] Combination Figure 1 and Figure 2 As shown, one end of the motor shaft 2 extends out of the motor housing 1 and is away from the controller housing 11 to form an output section 44. The other end of the motor shaft 2 extends into the controller housing 11 to form a sensing section 45 corresponding to the circuit board 12 located inside the controller housing 11. The circuit board 12 is connected to a wire 13 extending out from the end of the controller housing 11 away from the motor housing 1.

[0034] The controller housing 11 has a wire clamping block 14 on the outer side near the wire 13, which is in contact with the wire 13, and the wire clamping block 14 is connected to the controller housing 11 by a fixing bolt 15.

[0035] The principle of this embodiment is as follows: When the circuit board 12 inside the controller housing 11 is connected to the power supply and control signal via the wire 13, it will precisely control the current to flow into the winding of the yokeless stator 22. The winding is pre-embedded or wound in the space formed by the stator teeth 23 and the stator slots 25. The current flows through the winding and generates a magnetic field on each stator tooth 23. These teeth actually become independent electromagnets. Since the yoke is removed, the path of the magnetic field lines is completely changed. The magnetic field lines are emitted from one stator tooth 23, pass through the air gap and act on the rotor 21, and then directly enter the adjacent stator tooth 23 through the shortest path to form a loop.

[0036] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0037] Although this document frequently uses terms such as motor housing 1, controller housing 11, circuit board 12, wire 13, wire clamping block 14, fixing bolt 15, motor shaft 2, motor rotor 21, yokeless stator 22, stator teeth 23, tooth groove 24, stator slot 25, stator frame 26, stator cylindrical part 27, stator end cover 28, center hole 29, through slot structure 3, through slot body 31, first inclined part 4, second inclined part 41, horizontal part 42, partition part 43, output part 44, and sensing part 45, the possibility of using other terms is not excluded. The use of these terms is merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A novel micro motor without a yoke stator, comprising a motor housing (1) and a controller housing (11) disposed at one end of the motor housing (1), wherein a motor shaft (2) having a motor rotor (21) rotatably passes through the motor housing (1), characterized in that, The motor housing (1) has an inner side with a yokeless stator (22) located on the outer side of the motor rotor (21). The yokeless stator (22) has several stator teeth (23) arranged circumferentially on the outer side. The stator teeth (23) have axially extending grooves (24) that vertically penetrate the stator teeth (23). A stator slot (25) is formed between two adjacent stator teeth (23). The bottom of the stator slot (25) has a through slot structure (3) that communicates with the inner side of the yokeless stator (22).

2. The novel yokeless stator micro motor according to claim 1, characterized in that, The tooth groove (24) extends axially from one end of the stator tooth part (23) to the other end. One side of the tooth groove (24) penetrates the upper side of the stator tooth part (23) and the other side is connected to the inner side of the stator (22) without yoke.

3. A novel yokeless stator micro motor according to claim 1, characterized in that, The stator slot (25) has a structure that is wider at the top and narrower at the bottom, and the two ends of the stator slot (25) extend to the two ends of the stator (22) without yoke.

4. A novel yokeless micro motor according to claim 1, 2, or 3, characterized in that, The through-slot structure (3) includes several through-slot bodies (31) arranged at equal intervals at the bottom of the stator slot (25), and the through-slot bodies (31) are connected to the inner side of the stator (22) without yoke.

5. A novel yokeless stator micro motor according to claim 4, characterized in that, The yokeless stator (22) includes a stator cylindrical part (27) formed by a number of stator frames (26) evenly distributed in the circumference. The stator cylindrical part (27) has stator end caps (28) at both ends that are connected to the ends of each stator frame (26) and match the shape of the stator cylindrical part (27). The stator end caps (28) have a central hole (29) through which the motor rotor (21) passes.

6. A novel yokeless stator micro motor according to claim 5, characterized in that, The stator frame (26) has an inwardly concave curved cross section and the stator slots (25) are formed on the outer side of each stator frame (26). The stator teeth (23) are formed between two adjacent stator frames (26) and the stator end caps (28), and the tooth slots (24) are formed between the corresponding sides of the two adjacent stator frames (26).

7. A novel yokeless stator micro motor according to claim 6, characterized in that, The stator frame (26) includes two symmetrically arranged first inclined portions (4) that are inclined in opposite directions respectively. Each of the first inclined portions (4) has a second inclined portion (41) on one side, and the corresponding sides of the second inclined portions (41) are connected by a horizontal portion (42). The toothed grooves (24) are formed between the first inclined portions (4) of two adjacent stator frames (26), and the through slots (31) are arranged at equal intervals on the horizontal portion (42), and a partition (43) is formed between two adjacent through slots (31).

8. A novel yokeless stator micro motor according to claim 7, characterized in that, The first inclined portion (4) and the second inclined portion (41) form a 130-degree angle, and the second inclined portion (41) and the horizontal portion (42) form a 170-degree angle.

9. A novel yokeless stator micro motor according to claim 1, characterized in that, One end of the motor shaft (2) extends out of the motor housing (1) away from the controller housing (11) to form an output part (44), and the other end of the motor shaft (2) extends into the controller housing (11) to form a sensing part (45) corresponding to the circuit board (12) located in the controller housing (11). The circuit board (12) is connected to a wire (13) extending out from the end of the controller housing (11) away from the motor housing (1).

10. A novel yokeless stator micro motor according to claim 9, characterized in that, The controller housing (11) has a wire clamping block (14) on the outer side near the wire (13) that contacts the wire (13), and the wire clamping block (14) is connected to the controller housing (11) by a fixing bolt (15).

Images