A compression tooling

Abstract

The application relates to the technical field of motor magnetic cylinder assembly, in particular to a glue pressing tool, which comprises a base, the base is internally provided with a containing cavity, the base is configured on a stator surface, the containing cavity is used for containing a magnetic steel to be bonded so that the base limits the magnetic steel in the transverse direction, and the magnetic steel is bonded with the stator surface in the containing cavity; and a pressing assembly, the pressing assembly comprises a pressing plate, the pressing plate is rigidly arranged and used for bearing stress; and an elastic piece, the elastic piece is elastic and compressible and resilient, a first end of the elastic piece is fixedly connected to the pressing plate, and a second end of the elastic piece is used for acting on the magnetic steel so that the stress borne by the pressing plate is conducted to the magnetic steel through deformation of the elastic piece. The glue pressing tool is used for gluing and assembling the magnetic steel, and the surface flatness of the magnetic steel in the gluing process is improved.

Description

Technical Field

[0001] This application relates to the field of motor magnetic cylinder assembly technology, and in particular to a pressure bonding tool. Background Technology

[0002] Magnets are the core functional components of permanent magnet systems in motors. Through their stable magnetic properties, they provide a crucial magnetic field foundation for motor operation and are an important part of the motor's electromagnetic conversion module. As the core equipment for converting electrical energy into mechanical energy, motors are widely used in industrial drives, precision control, and other fields. High-precision motors (such as those used in high-end equipment and precision instruments) have stringent requirements for the assembly precision of core components. The assembly quality of magnets directly determines the stability of the motor's magnetic field, power output efficiency, and overall control precision, and is one of the key factors affecting the upper limit of motor performance.

[0003] In existing technologies, controlling the flatness of magnet surfaces during magnet assembly faces significant challenges. Due to the magnets' inherent magnetism and the need for adhesive bonding to the stator surface during assembly, factors such as magnetic adsorption deviation, uneven adhesive distribution, and assembly positioning datum deviation can easily lead to a situation where multiple assembled magnets cannot form a uniformly flat plane. This flatness error exceeds the accuracy standard, affecting the uniformity of the air gap inside the motor and subsequently causing magnetic field distribution disorder. This has a chain reaction of negative impacts on the motor's core performance, such as power output stability and dynamic response speed.

[0004] Therefore, the technical problem with the existing technology is that the surface flatness of the magnet is poor during the magnet bonding process. Utility Model Content

[0005] This application provides a pressure bonding fixture, which improves the surface flatness of the magnet during the bonding process by using the fixture to glue and assemble the magnet.

[0006] This application provides a pressure bonding fixture, which adopts the following technical solution: A pressure bonding fixture includes: a base having a receiving cavity inside, the base being disposed on a stator surface, the receiving cavity being used to receive a magnet to be bonded so that the base laterally limits the magnet, thereby bonding the magnet to the stator surface within the receiving cavity; and a pressure applying assembly including: a pressure plate, the pressure plate being rigidly disposed and used to bear force; and an elastic element, the elastic element being elastic and compressible, a first end of the elastic element being fixedly connected to the pressure plate, and a second end of the elastic element being used to act on the magnet, so as to transmit the force on the pressure plate to the magnet through the deformation of the elastic element.

[0007] Preferably, the pressure application component further includes a suction block located at the second end of the elastic member, the suction block being fixedly connected to the elastic member, the suction block being magnetic, and the suction block being used to generate an upward magnetic attraction force on the magnet.

[0008] Preferably, the elastic element is an elastic plate, and a receiving groove is provided on the second end of the elastic element. The suction block is located in the receiving groove and is fixedly connected to the inner wall of the receiving groove.

[0009] Preferably, the suction block has a first surface for contacting the magnet, and the elastic element has a second surface for contacting the magnet, with the first surface and the second surface being flush.

[0010] Preferably, the depth of the receiving groove is greater than the thickness of the suction block, so that a buffer cavity is formed between the suction block and the elastic plate within the receiving groove.

[0011] Preferably, the suction block is located in the center of the elastic member, so that the elastic member forms an annular force-bearing area around the suction block.

[0012] Preferably, a gap is formed between the base and the pressure plate, and the elastic element has a first state before compression and a second state after compression: in the first state, a first gap H1 is formed between the base and the pressure plate; in the second state, a second gap H2 is formed between the base and the pressure plate; wherein, H1 > H2 > 0.

[0013] Preferably, the base includes: a baffle, wherein multiple baffles are arranged to form the receiving cavity; and a plug-in portion connected to the bottom of the baffle, which is used to plug into a hole on the stator surface to fix the base to the stator surface; wherein an overflow notch is formed between the bottom of the baffle and the stator surface, the overflow notch communicating with the receiving cavity, and the overflow notch is used for overflowing adhesive during the bonding process of the magnet.

[0014] Preferably, the device further includes a limiting plate, which is rigidly disposed and positioned between the magnet and the stator surface to limit the minimum thickness of the adhesive layer between the magnet and the stator surface.

[0015] Preferably, there are multiple limiting plates, which are uniformly arranged between the magnet and the stator surface.

[0016] In summary, this application includes at least one of the following beneficial technical effects: This application limits the magnet by using a base, and transmits the force on the pressure plate to the magnet through the deformation of the elastic element. This is beneficial for applying pressure to the magnet evenly, improving the assembly and pressing accuracy of the magnet, and improving the flatness of the magnet surface during the gluing process. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the first type of pressure bonding fixture described in this application; Figure 2 This is a second schematic diagram of the pressure bonding tooling described in this application; Figure 3 This is a schematic diagram of the fit between the base and the stator surface of the pressure bonding fixture described in this application; Figure 4 This is a schematic diagram of the adhesive overflow notch of the pressure bonding tool described in this application; Figure 5 This is a schematic diagram of the pressure application component of the adhesive bonding fixture described in this application.

[0018] Explanation of reference numerals in the attached drawings: 100, base; 110, baffle; 120, receiving cavity; 130, insertion part; 140, overflow notch; 200, pressure component; 210, pressure plate; 220, elastic element; 221, elastic plate; 2211, second surface; 2212, receiving groove; 2213, buffer cavity; 2214, annular force-bearing area; 222, spring; 230, suction block; 231, first surface; 300, limiting plate; 400, magnet; 500, stator surface; 510, insertion hole; 600, gap. Detailed Implementation

[0019] The serial numbers assigned to components in this document, such as "first" and "second," are used solely to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used solely for the convenience of describing this application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0020] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0021] This application provides a pressure bonding fixture, which improves the surface flatness of the magnet 400 during the bonding process by using the fixture to perform adhesive bonding assembly of the magnet 400.

[0022] To better understand the above technical solutions, a detailed description of the technical solutions will be provided below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit the scope of this application.

[0023] The core shortcoming of existing magnet 400 assembly technology lies in the failure to effectively solve the flatness control problem during the magnet 400 bonding process. In the bonding assembly stage between the magnet 400 and the stator surface 500, existing technology lacks a precise control mechanism for the positioning accuracy of the magnet 400 and the curing morphology of the adhesive. It cannot reliably offset the impact of magnetic interference and assembly deviations on flatness through technical means. This results in poor surface flatness of the bonded magnet 400, a common technical bottleneck. This problem not only limits the upgrade of conventional motors to higher precision levels but also makes it difficult to meet the stringent requirements of high-precision motors for the assembly accuracy of the magnet 400, becoming a key technical obstacle restricting motor performance improvement.

[0024] Currently, the adhesive curing of conventional motor magnets (400) mainly employs two pressure application methods: one is a screw-pressure plate (210) that applies pressure to the adhesive by controlling torque; the other is to stack weights on the magnets (400) to achieve pressure. However, these two existing technologies have significant shortcomings: First, due to the inability to guarantee absolute perpendicularity between the screw and the pressure point, the adhesive curing pressure converted from torque deviates from the actual requirements, making precise pressure application difficult. Second, the contact area between the screw and the pressure plate (210) is much smaller than the total area of ​​the pressure plate (210). Even with pressure distribution through the pressure plate (210), stress concentration cannot be avoided, resulting in poor uniformity of adhesive curing pressure. Furthermore, the screw and thread are loosely fitted, making it impossible to guarantee consistent final results in multiple magnet (400) bonding operations. This makes it impossible to achieve precise control over the surface flatness of multiple bonded magnets (400), and even more so to meet the precise control requirements of high-precision motors for adhesive layer curing thickness.

[0025] The current bonding and curing technology for magnet 400 is ill-suited for the demands of high-precision motors. The core technical challenge lies in overcoming the limitations of existing pressure application methods to achieve precise control, uniform distribution, and consistent, stable results in the adhesive curing pressure during the magnet 400 bonding process. This would improve the bonding precision of the magnet 400, ensuring that the flatness of multiple bonded magnets reaches near-micron-level standards required by high-precision motors, thus guaranteeing stable performance. Therefore, a device or method to improve the bonding precision of magnet 400 is urgently needed.

[0026] This application proposes a pressure bonding fixture, such as Figure 1-5 As shown, this is used to assist in bonding the magnet 400 to the stator surface 500, thereby improving the bonding accuracy of the magnet 400 during the assembly and bonding process, and ensuring that the flatness of multiple bonded magnets 400 reaches the near-wire-level standard required for high-precision motors. A pressure-pressing fixture includes a base 100 and a pressure-applying component 200. The base 100 serves as the overall foundation of the pressure-pressing fixture and can restrict the lateral displacement of the magnet 400. The pressure-applying component 200 is used to transmit external force to the magnet 400 to achieve the required curing pressure for the adhesive located between the magnet 400 and the stator surface 500.

[0027] like Figure 1 , 2 As shown, the base 100 serves as the overall foundation of the pressure bonding fixture, restricting the lateral displacement of the magnet 400. The base 100 acts as the positioning and fixing base for the pressure bonding fixture of this application. The base 100 has an internal receiving cavity 120. The base 100 is positioned on the stator surface 500, and the receiving cavity 120 accommodates the magnet 400 to be bonded, allowing the base 100 to laterally limit the magnet 400, ensuring that the magnet 400 is bonded to the stator surface 500 within the receiving cavity 120. Figure 3 , 4 As shown, the base 100 includes multiple baffles 110. In one embodiment, the baffles 110 are rectangular baffles 110. Multiple baffles 110 are connected to each other and enclose a receiving cavity 120. The size of the receiving cavity 120 is adapted to the magnet 400. Space can be reserved between the baffles 110 and the magnet 400, and the magnet 400 can be laterally limited by the inner wall of the baffles 110. When the magnet 400 is arranged in the receiving cavity 120, the magnet 400 is fixed in position by the baffles 110. The magnet 400 is pressed down by the pressure application component 200, so that the magnet 400 is located in the receiving cavity 120 and completes the bonding with the stator surface 500.

[0028] Furthermore, such as Figure 3 As shown, the base 100 also includes a plug-in portion 130, which is connected to the bottom of the baffle 110. The plug-in portion 130 is used to plug into the socket 510 on the stator surface 500 to fix the base 100 to the stator surface 500. An overflow notch 140 is formed between the bottom of the baffle 110 and the stator surface 500. The overflow notch 140 communicates with the receiving cavity 120 and is used for overflowing adhesive during the bonding process of the magnet 400. In other words, the plug-in portion 130 is fixedly connected to the bottom of the baffle 110, or the plug-in portion 130 is integrally formed with the baffle 110. The plug-in portion 130 is used to plug into the pre-set socket 510 on the stator surface 500. During assembly, the plug-in portion 130 is inserted into the socket 510, which can limit the loosening and displacement of the base 100 and play a role in fixing the position of the base 100.

[0029] More specifically, such as Figure 4 As shown, an overflow notch 140 is formed between the bottom of the baffle 110 and the stator surface 500. The overflow notch 140 is connected to the receiving cavity 120 and is used for overflowing adhesive during the bonding process of the magnet 400. An overflow notch 140 is provided at the bottom of each baffle 110. The overflow notch 140 can be formed on the baffle 110 or in the gap formed between the baffle 110 and the stator surface 500. The overflow notch 140 is directly connected to the receiving cavity 120, so that during the assembly and pressing of the magnet 400, excess adhesive between the magnet 400 and the stator surface 500 can overflow through the overflow notch 140, avoiding adhesive residue.

[0030] Pressure component 200, such as Figure 1 , 2 As shown, the pressure application assembly 200 is used to transmit external force to the magnet 400 to achieve the required curing pressure for the adhesive located on the magnet 400 and the stator surface 500. The pressure application assembly 200 serves as a pressure transmission structure for the tooling and includes a pressure plate 210 and an elastic element 220. The pressure plate 210 is rigid and is used to withstand external pressure, ensuring that the pressure is transmitted to the elastic element 220 without deviation during external pressure application. The elastic element 220 is elastic and compressible. Its first end is fixedly connected to the pressure plate 210, and its second end acts on the magnet 400 to transmit the force on the pressure plate 210 to the magnet 400 through the deformation of the elastic element 220. In one embodiment, the elastic element 220 can be an elastic plate 221; in another embodiment, it can be a spring 222. The first end of the elastic element 220 can be fixedly connected to the pressure plate 210 by adhesive or screws, and the second end acts on the top surface of the magnet 400 to transmit pressure to it. The elastic element 220 achieves uniform pressure diffusion and transmission through deformation. Based on the expected required pressure, the current pressure is characterized by calculating the deformation of the elastic element 220, thereby controlling the adhesive layer thickness.

[0031] Furthermore, such as Figure 1 , 2As shown, the pressure application assembly 200 also includes a suction block 230, which is located on the second end of the elastic member 220 and is fixedly connected to the elastic member 220. The suction block 230 is magnetic and is used to generate an upward magnetic attraction force on the magnet 400. The suction block 230 is fixedly connected to the second end of the elastic member 220 and can generate an upward magnetic attraction force on the magnet 400. In one embodiment, the suction block 230 uses a neodymium iron boron permanent magnet; in other embodiments, the suction block 230 can also use an electromagnet. It should be noted that during the assembly and pressing process, the total downward impact force of the magnet 400 is the sum of the magnet 400's own weight and the attractive force between the magnet 400 and the stator surface 500. The magnetic attraction force of the suction block 230 needs to be greater than the total impact force to counteract the downward impact of the magnet 400, allowing the magnet 400 to slowly adhere to the stator surface 500.

[0032] As a preferred option, such as Figure 5 As shown, the elastic element 220 can be selected as an elastic plate 221. Further, a receiving groove 2212 is formed on the second end of the elastic element 220, and the suction block 230 is located within the receiving groove 2212, with the suction block 230 fixedly connected to the inner wall of the receiving groove 2212. In other words, the second end of the elastic plate 221 has a receiving groove 2212, and the suction block 230 is embedded inside the receiving groove 2212. More specifically, the suction block 230 and the inner wall of the receiving groove 2212 are fixedly connected by an interference fit and / or adhesive bonding, ensuring that the suction block 230 is not loose, avoiding displacement of the suction block 230 which could lead to uneven magnetism and affect the adsorption effect.

[0033] Furthermore, such as Figure 5 As shown, the suction block 230 has a first surface 231 for contacting the magnet 400, and the elastic member 220 has a second surface 2211 for contacting the magnet 400. The first surface 231 and the second surface 2211 are flush. On the suction block 230, the surface of the suction block 230 that contacts and magnetically attracts the magnet 400 is defined as the first surface 231. On the elastic plate 221, the surface of the elastic plate 221 that contacts the magnet 400 is defined as the second surface 2211. The first surface 231 of the suction block 230 that contacts the magnet 400 and the second surface 2211 of the elastic plate 221 that contacts the magnet 400 are flush or substantially flush (within the allowable flatness error). If the suction block 230 protrudes relative to the elastic plate 221, the pressure is concentrated on the suction block 230; if the suction block 230 is recessed relative to the elastic plate 221, the suction block 230 cannot attract. The flush design of the suction block 230 and the elastic plate 221 ensures that "attraction + pressure transmission" are achieved simultaneously, and the pressure is evenly distributed over the magnet 400.

[0034] Furthermore, such as Figure 5As shown, the depth of the receiving groove 2212 is greater than the thickness of the suction block 230, so that a buffer cavity 2213 is formed between the suction block 230 and the elastic plate 221 within the receiving groove 2212. The depth of the receiving groove 2212 needs to be greater than the thickness of the suction block 230 to form a buffer cavity 2213 between the top of the suction block 230 and the elastic plate 221. The buffer cavity 2213 is used to buffer the elastic plate 221 during compression, preventing the elastic plate 221 from contacting the suction block 230 during compression. The suction block 230 is located in the center of the elastic member 220, so that the elastic member 220 forms an annular force-bearing area 2214 located around the suction block 230. The suction block 230 is located in the center of the elastic plate 221, and an annular force-bearing area 2214 is formed around the elastic plate 221. The pressure is evenly diffused from the central suction block 230 to the annular area, which is conducive to the uniform transmission of pressure during the pressure application process. The annular force-bearing area 2214 refers to a closed annular area, not limited to a circular ring, and can also be square or other shapes.

[0035] like Figure 1 , 2 As shown, a gap 600 is formed between the base 100 and the pressure plate 210, and the elastic member 220 has a first state before compression and a second state after compression: in the first state, a first gap H1 is formed between the base 100 and the pressure plate 210; in the second state, a second gap H2 is formed between the base 100 and the pressure plate 210; wherein, H1 > H2 > 0 is satisfied.

[0036] Specifically, a variable gap 600 is formed between the top surface of the base 100 and the bottom surface of the pressure plate 210, and the elastic element 220 corresponds to two working states: In the first state (elastic element 220 is not compressed): elastic element 220 is naturally extended, and the gap 600 is H1; In the second state (compression of elastic element 220): elastic element 220 is compressed to the preset deformation, and the gap 600 is reduced to H2; satisfying H1>H2>0, avoiding rigid collision between pressure plate 210 and base 100.

[0037] Operators do not need specialized instruments; they can determine the compression of the elastic element 220 simply by measuring the difference between H1 and H2, and thus calculate the pressure value corresponding to the current adhesive.

[0038] Furthermore, such as Figure 1 , 2As shown, the pressure-pressing fixture also includes a limiting plate 300. The limiting plate 300 is rigidly positioned and is used to limit the minimum thickness of the adhesive layer between the magnet 400 and the stator surface 500. The limiting plate 300 is used to prevent excessive pressure of the adhesive and maintains the minimum thickness of the adhesive layer through rigid support. The limiting plate 300 is made of rigid material and its thickness is equal to or approximately equal to the preset minimum thickness of the adhesive layer. It is positioned between the bottom surface of the magnet 400 and the stator surface 500. The adhesive layer must maintain a minimum thickness during curing (otherwise, the bonding strength will be insufficient). The limiting plate 300 is extremely rigid and can limit the downward pressure of the magnet 400, ensuring the thickness of the adhesive layer. Even if excessive pressure is applied, the bottom surface of the magnet 400 will be supported by the limiting plate 300, preventing further downward pressure. In one embodiment, there are more than 300 limiting plates, which are uniformly arranged between the magnet 400 and the stator surface 500 and are evenly distributed circumferentially along the bottom surface of the magnet 400.

[0039] It should be noted that the elastic modulus of the pressure plate 210, the limiting plate 300, and the magnet 400 should all be greater than and much greater than that of the elastic element 220, so that the elastic element 220 is deformed under pressure when the pressure component 200 presses down on the magnet 400.

[0040] Thus, the base 100 is stably fixed by the insertion part 130, and the accommodating cavity 120 restricts the lateral displacement of the magnet 400; the magnetic block 230 counteracts the impact, and the elastic element 220 ensures uniform pressure transmission; the limiting plate 300 controls the minimum thickness of the adhesive layer, and the overflow notch 140 drains excess adhesive; the pressure state is judged by the change of the gap 600, and finally the high-precision bonding of the magnet 400 is achieved.

[0041] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0042] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A pressure bonding fixture, characterized in that, include: A base (100) having an internal cavity (120) is provided. The base (100) is disposed on a stator surface (500). The cavity (120) is used to accommodate a magnet (400) to be bonded so that the base (100) laterally limits the magnet (400) so that the magnet (400) is bonded to the stator surface (500) within the cavity (120). A pressure application assembly (200), the pressure application assembly (200) comprising: Pressure plate (210), the pressure plate (210) is rigidly set, the pressure plate (210) is used to bear force; An elastic element (220) is elastic and compressible. The first end of the elastic element (220) is fixedly connected to the pressure plate (210), and the second end of the elastic element (220) is used to act on the magnet (400) so as to transmit the force on the pressure plate (210) to the magnet (400) through the deformation of the elastic element (220).

2. The pressure bonding fixture according to claim 1, characterized in that, The pressure application assembly (200) also includes: A suction block (230) is located on the second end of the elastic member (220). The suction block (230) is fixedly connected to the elastic member (220). The suction block (230) is magnetic and is used to generate an upward magnetic attraction force on the magnet (400).

3. The pressure bonding fixture according to claim 2, characterized in that, The elastic element (220) is an elastic plate (221). A receiving groove (2212) is provided on the second end of the elastic element (220). The suction block (230) is located in the receiving groove (2212). The suction block (230) is fixedly connected to the inner wall of the receiving groove (2212).

4. The pressure bonding fixture according to claim 3, characterized in that, The suction block (230) has a first surface (231) for contacting the magnet (400), and the elastic element (220) has a second surface (2211) for contacting the magnet (400), with the first surface (231) and the second surface (2211) being flush.

5. The pressure bonding fixture according to claim 3, characterized in that, The depth of the receiving groove (2212) is greater than the thickness of the suction block (230) so that a buffer cavity (2213) is formed between the suction block (230) and the elastic plate (221) within the receiving groove (2212).

6. The pressure bonding fixture according to claim 3, characterized in that, The suction block (230) is located in the center of the elastic member (220) so that the elastic member (220) forms an annular force-bearing area (2214) on the periphery of the suction block (230).

7. A pressure bonding fixture according to any one of claims 1-6, characterized in that, A gap (600) is formed between the base (100) and the pressure plate (210), and the elastic element (220) has a first state before compression and a second state after compression: In the first state, a first gap H1 is formed between the base (100) and the pressure plate (210); In the second state, a second gap H2 is formed between the base (100) and the pressure plate (210); Among them, H1 > H2 > 0.

8. The pressure bonding fixture according to claim 1, characterized in that, The base (100) includes: A baffle (110) is provided, and the baffles (110) are arranged in a plurality of such baffles to form the receiving cavity (120). A plug-in portion (130) is connected to the bottom of the baffle (110). The plug-in portion (130) is used to engage with the plug hole (510) on the stator surface (500) so that the base (100) is fixed to the stator surface (500). Wherein, an overflow notch (140) is formed between the bottom of the baffle (110) and the stator surface (500), the overflow notch (140) is connected to the accommodating cavity (120), and the overflow notch (140) is used for overflow during the bonding process of the magnet (400).

9. The pressure bonding fixture according to claim 1, characterized in that, Also includes: A limiting plate (300) is rigidly disposed between a magnet (400) and a stator surface (500) to limit the minimum thickness of the adhesive layer between the magnet (400) and the stator surface (500).

10. The pressure bonding fixture according to claim 9, characterized in that, Multiple limiting plates (300) are used to be uniformly arranged between the magnet (400) and the stator surface (500).

Images