Bearingless permanent magnet synchronous motor

Abstract

The utility model relates to the technical field of motors, and discloses a bearingless permanent magnet synchronous motor, which comprises a casing, and a stator core, a rotor core and an inner hole rotating shaft which are sequentially arranged in the casing from outside to inside, a stator winding is arranged on the stator core, and the casing, the stator core and the stator winding are combined to form a stator assembly; the rotor iron core is sleeved on the inner hole rotating shaft, and magnetic steel is arranged on the rotor iron core; the rotor iron core, the magnetic steel and the inner hole rotating shaft are combined to form a rotor assembly; and epoxy resin layers are encapsulated outside the stator core and the stator winding. According to the arrangement, the stator core and the stator winding are encapsulated by the epoxy resin layer, so that the protection level of the motor is remarkably improved, the protection level is improved from a lower protection level to a higher standard, heat generated by the stator winding can be quickly conducted to the casing, and the temperature distribution of the motor is more uniform.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, and in particular to a bearingless permanent magnet synchronous motor. Background Technology

[0002] In today's industrial sector and numerous electromechanical equipment applications, electric motors, as key power drive components, are crucial for stable operation and reliability. Shaftless motors, with their unique structural advantages such as compact design and high power density, are widely used in applications with stringent space and performance requirements, including precision instruments, robot joint drives, and high-end automated production lines.

[0003] Traditional shaftless motors have significant limitations in terms of protection performance. Taking a common shaftless motor with an IP23 protection rating as an example, this rating means the motor can protect against objects larger than 12mm in diameter and prevent damage from vertically dripping water. However, in complex actual working conditions, such as poor air quality and uncontrollable equipment environments, motors inevitably come into contact with various liquid media. Once liquids such as water or oil penetrate into the area where the stator copper coils are located, it will cause a series of serious problems. On the one hand, the conductivity of water can cause short circuits in the stator coils, leading to abnormal motor operation or even instantaneous burnout, significantly shortening the motor's lifespan. Frequent repairs and replacements not only increase costs but also extend equipment downtime, severely impacting production efficiency. On the other hand, oily substances adhering to the coil surface will gradually accumulate dust and impurities, forming a dirt layer that hinders heat dissipation, causing the coil temperature to become excessively high, similarly reducing the motor's reliability and operational stability.

[0004] To address the challenges of motor protection and enhance its adaptability to complex environments, various methods have been explored in existing technologies. Some motors employ additional sealed housings, which, while preventing external liquid intrusion to some extent, still allow liquid to seep in through gaps in the housing and the motor body, as well as through ventilation holes. Furthermore, this approach increases the overall size and weight of the motor, hindering miniaturization and weight reduction. Another solution involves coating the motor surface with a waterproof and oil-resistant coating; however, this coating has limited thickness and is prone to wear and peeling after prolonged use, failing to provide lasting and effective protection for the stator coils.

[0005] It is evident that existing technologies still need improvement and enhancement. Utility Model Content

[0006] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a bearingless permanent magnet synchronous motor, which aims to inject epoxy resin into the stator core and stator coil to form an epoxy resin layer, thereby using the epoxy resin layer to block water and oil and improve the protection level of the motor.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A bearingless permanent magnet synchronous motor includes a housing, a stator core, a rotor core, and an inner bore shaft arranged sequentially from the outside to the inside of the housing; the stator core is provided with stator windings, and the housing, the stator core, and the stator windings are combined to form a stator assembly; the rotor core is sleeved on the inner bore shaft and is provided with magnets; the rotor core, the magnets, and the inner bore shaft are combined to form a rotor assembly; the stator core and the stator windings are externally encapsulated with an epoxy resin layer.

[0009] The bearingless permanent magnet synchronous motor, wherein the housing includes a heat dissipation sleeve, a first flange disposed at the front end of the heat dissipation sleeve, and a rear cover plate disposed at the rear end of the heat dissipation sleeve.

[0010] The bearingless permanent magnet synchronous motor has a base block fixed to the bottom of the heat dissipation housing, and the base block has a locking hole.

[0011] In the aforementioned bearingless permanent magnet synchronous motor, both the first flange and the rear cover plate have central through holes, and the tail end of the inner bore shaft passes through the central through hole on the rear cover plate and is fixedly connected to the wind turbine.

[0012] In the aforementioned bearingless permanent magnet synchronous motor, a shroud located on the outer periphery of the impeller is fixedly connected to the tail end of the heat dissipation housing, and the shroud has a plurality of heat dissipation ring holes.

[0013] In the aforementioned bearingless permanent magnet synchronous motor, the central through hole on the first flange is pierced by the transmission rod of the oil pump, and the transmission rod is connected to the inner bore shaft by a key connection; a second flange is provided on the rear end of the oil pump, and the first flange and the second flange are connected by butt bolts.

[0014] The bearingless permanent magnet synchronous motor is further provided with an electrical wire lead-out pipe communicating with its inner cavity on the housing.

[0015] Beneficial effects:

[0016] This invention provides a bearingless permanent magnet synchronous motor that utilizes epoxy resin to encapsulate the stator core and stator windings, significantly improving the motor's protection level from a lower to a higher standard. Furthermore, compared to traditional motors without resin encapsulation or those employing other poorly heat-dissipating protection methods, the excellent thermal conductivity of epoxy resin provides an effective way for heat dissipation. By rapidly transferring heat generated in the stator windings to the motor housing, it prevents localized heat accumulation in the stator windings, resulting in a more uniform temperature distribution. This reduces the risk of insulation aging and winding short circuits caused by overheating, further enhancing the motor's operational stability, extending its continuous operating time, and improving production efficiency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the internal structure of a bearingless permanent magnet synchronous motor provided by this utility model.

[0018] Figure 2 This is a schematic diagram of a bearingless permanent magnet synchronous motor.

[0019] Explanation of main component symbols: 11-House, 111-Heat dissipation sleeve, 112-First flange, 113-Rear cover, 114-Center perforation, 115-Electric wire lead-out pipe, 12-Stator core, 21-Rotor core, 22-Inner bore shaft, 3-Epoxy resin layer, 4-Impeller, 5-Wind cover, 51-Heat dissipation ring hole, 6-Foot block, 61-Lock hole, 71-Oil pump, 72-Transmission rod, 73-Second flange, 74-Matching screw. Detailed Implementation

[0020] This utility model provides a bearingless permanent magnet synchronous motor. To make the purpose, technical solution, and effects of this utility model clearer and more explicit, the following describes this utility model in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit the scope of protection of this utility model.

[0021] Please see Figures 1-2 This utility model provides a bearingless permanent magnet synchronous motor, including a housing 11, a stator core 12, a rotor core 21, and an inner bore shaft 22 arranged sequentially from the outside to the inside of the housing 11; the stator core 12 is provided with a stator winding 13, and the housing 11, the stator core 12, and the stator winding 13 are combined to form a stator assembly; the rotor core 21 is sleeved on the inner bore shaft 22 and is provided with a magnet; the rotor core 21, the magnet, and the inner bore shaft 22 are combined to form a rotor assembly; the stator core 12 and the stator winding 13 are externally encapsulated with an epoxy resin layer 3.

[0022] In practical applications, when a bearingless permanent magnet synchronous motor is connected to three-phase AC power, a rotating magnetic field is generated in the stator winding 13. According to the principle of electromagnetic induction, the rotating magnetic field will interact with the magnets on the rotor core 21. Due to the repulsion of like poles and the attraction of unlike poles, the rotor assembly is subjected to a rotating electromagnetic force, which drives the inner shaft 22 to start rotating, thereby realizing the power output of the motor.

[0023] The stator core 12 and stator winding 13 are externally encapsulated with an epoxy resin layer 3. This epoxy resin layer 3 primarily acts as a physical barrier. When the motor is in a complex environment, such as where water, oil, dust, or other impurities are present, the epoxy resin layer 3, with its dense structure, can effectively block external liquid media (such as water mist, oil droplets, etc.) and solid particles (dust, etc.), preventing them from contacting the stator winding 13. This avoids short-circuit faults caused by the conductivity of water or heat dissipation obstructed by the accumulation of dirt due to oil adhesion. At the same time, the epoxy resin layer 3 has a certain thermal conductivity. During motor operation, the stator winding 13 generates heat due to the current flowing through it. This heat can be conducted to the housing 11 through the tightly contacting epoxy resin layer 3. The housing 11 typically has a large heat dissipation area, further dissipating the heat into the surrounding environment, thereby achieving effective heat dissipation for the motor and maintaining the stator winding 13 within a suitable operating temperature range, ensuring stable motor operation.

[0024] The aforementioned bearingless permanent magnet synchronous motor utilizes epoxy resin layer 3 to encapsulate the stator core 12 and stator windings 13, significantly improving the motor's protection level from a relatively low level (similar to IP23 commonly found in traditional shaftless motors) to a higher standard, such as approaching or reaching IP54. Furthermore, compared to traditional motors without resin encapsulation or those employing other poor heat dissipation protection methods, the excellent thermal conductivity of epoxy resin provides an effective way for motor heat dissipation. By rapidly conducting the heat generated by the stator windings 13 to the housing 11, it avoids localized heat accumulation in the stator windings 13, resulting in a more uniform temperature distribution. This reduces the risk of insulation aging and winding short circuits caused by overheating, further enhancing the motor's operational stability, extending its continuous operating time, and improving production efficiency.

[0025] In some embodiments, the housing 11 includes a heat dissipation sleeve 111, a first flange 112 disposed at the front end of the heat dissipation sleeve 111, and a rear cover plate 113 disposed at the rear end of the heat dissipation sleeve 111. The design of the heat dissipation sleeve 111 increases the surface area of ​​the housing 11, which is conducive to the rapid dissipation of heat, thereby improving the heat dissipation performance of the motor and ensuring that the motor can maintain a low operating temperature under high load conditions. The central through hole 114 on the first flange 112 and the rear cover plate 113 provides the necessary passage for the installation of the stator assembly. The rotor assembly and the impeller 4 can pass smoothly through the central through hole 114, making the installation process more convenient.

[0026] In some embodiments, a base block 6 is fixedly connected to the bottom of the heat dissipation housing 111, and a locking hole 61 is provided on the base block 6. The base block 6 increases the contact area between the motor and the mounting surface, which helps to improve the installation stability of the motor, especially in environments with high vibration, and can reduce the vibration and displacement of the motor. When installing the motor, after passing the screw through the locking hole 61, the screw is driven into the mounting object to fix the motor to the mounting object.

[0027] In some embodiments, both the first flange 112 and the rear cover plate 113 have a central through hole 114. The tail end of the inner shaft 22 passes through the central through hole 114 on the rear cover plate 113 and is fixedly connected to the impeller 4. When the inner shaft 22 rotates, it can drive the impeller 4 to rotate synchronously, so that the heat generated inside the motor is drawn out and discharged by the impeller 4, which can play a role in heat dissipation.

[0028] In some embodiments, a fan shroud 5 is fixedly connected to the tail of the heat dissipation housing 111, located on the outer periphery of the impeller 4. The fan shroud 5 has several heat dissipation ring holes 51. The design of the fan shroud 5 guides the airflow generated by the impeller 4 in a specific direction, ensuring effective utilization of the airflow and thus improving heat dissipation efficiency. Furthermore, the presence of the heat dissipation ring holes 51 allows air to flow in and out smoothly, helping to remove more heat. The presence of the fan shroud 5 prevents foreign objects from entering the motor, protecting the motor from external factors, and also prevents accidental contact with the high-speed rotating impeller 4 by personnel, improving operational safety.

[0029] In some embodiments, the central through hole 114 on the first flange 112 is pierced by the drive rod 72 of the oil pump 71, and the drive rod 72 is connected to the inner bore shaft 22 by a key connection. A second flange 73 is provided on the rear end of the oil pump 71, and the first flange 112 and the second flange 73 are connected by butt screws 74. The key connection between the drive rod 72 and the inner bore shaft 22 ensures a firm connection between them and improves the stability and reliability of the transmission. The butt screws 74 are used to assemble the first flange 112 and the second flange 73, enabling quick installation of the oil pump 71 and the motor. During operation, the magnetic field interaction between the stator assembly and the rotor assembly of the bearingless permanent magnet synchronous motor generates rotational force in the inner bore shaft 22, thereby driving the drive shaft to rotate. Therefore, the bearingless permanent magnet synchronous motor oil pump 71 is the drive source, reducing mechanical losses and improving the overall drive efficiency, making the oil pump 71 more efficient in conveying fluids.

[0030] In some embodiments, the housing 11 is further provided with a wire outlet tube 115 communicating with its internal cavity. The motor requires an external power supply to operate, and the stator winding 13 is connected to the external power supply via wires. The wire outlet tube 115 provides a dedicated passage for these wires, allowing them to be orderly led out of the motor cavity, preventing them from being haphazardly distributed inside the housing 11. Combined with the epoxy resin layer 3 encapsulating the stator core 12 and the windings, the wire outlet tube 115 further strengthens the overall protection system of the motor. The wire outlet tube 115 further prevents water and oil from entering the motor cavity along the wires and damaging the insulation performance of the stator winding 13.

[0031] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to 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 utility model.

[0032] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0033] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0034] It is understood that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of this utility model, and all such substitutions or changes should fall within the protection scope of this utility model.

Claims

1. A bearingless permanent magnet synchronous motor, characterized by, The machine shell, stator core, rotor core and inner hole rotating shaft are sequentially arranged in the machine shell from outside to inside; the stator core is provided with a stator winding; the machine shell, the stator core and the stator winding combine to form a stator assembly; the rotor core is sleeved on the inner hole rotating shaft and is provided with a magnetic steel; the rotor core, the magnetic steel and the inner hole rotating shaft combine to form a rotor assembly; the stator core and the stator winding are externally filled with an epoxy resin layer.

2. The bearingless permanent magnet synchronous motor according to claim 1, characterized in that, The machine shell comprises a heat dissipation sleeve shell, a first flange plate arranged at the front end of the heat dissipation sleeve shell and a rear cover plate arranged at the rear end of the heat dissipation sleeve shell.

3. The bearingless permanent magnet synchronous motor according to claim 2, characterized in that, The bottom of the heat dissipation sleeve shell is fixedly connected with a foot block, and a lock hole is arranged on the foot block.

4. The bearingless permanent magnet synchronous motor according to claim 2, characterized in that, A central through hole is arranged on the first flange plate and the rear cover plate, and the tail end of the inner hole rotating shaft is fixedly connected with a wind wheel after passing through the central through hole of the rear cover plate.

5. The bearingless permanent magnet synchronous motor according to claim 4, characterized in that, The tail of the heat dissipation sleeve shell is fixedly connected with a wind cover located outside the wind wheel, and a plurality of heat dissipation ring holes are arranged on the wind cover.

6. The bearingless permanent magnet synchronous motor according to claim 4, characterized in that, The central through hole of the first flange plate is penetrated by a transmission rod of an oil pump, and the transmission rod is connected with the inner hole rotating shaft in a key connection mode; a second flange plate is arranged on the rear end of the oil pump, and the first flange plate and the second flange plate are connected through butt screws.

7. The bearingless permanent magnet synchronous motor according to claim 1, characterized by, An electric wire leading pipe is further arranged on the machine shell and communicates with the inner cavity of the machine shell.

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