A position sensor for high-speed magnetic levitation motor and its potting method

Abstract

The present invention belongs to the technical field of magnetic levitation motors, and in particular relates to a position sensor for a high-speed magnetic levitation motor, comprising a base, a mounting hole for a rotor to pass through, an inductance component and a circuit board arranged in the mounting hole, an insulation component arranged between the inductance component and the circuit board, the inductance component, the insulation component and the circuit board being fixedly connected to the base, a potting glue layer being potted at positions around the inductance component, the insulation component and the circuit board in the mounting hole, and a circular ring-shaped gap being provided between the potting glue layer and the rotor. The present invention also discloses a potting method for a position sensor for a high-speed magnetic levitation motor, the present invention having a reasonable structure, a simple and efficient potting process, and a reliable potting effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic levitation motors, and in particular relates to a position sensor for a high-speed magnetic levitation motor and a potting method thereof. Background Art

[0002] With the development of science and technology and the demand for production, magnetic levitation high-speed motors have become one of the hot topics in the international electrical engineering field. Magnetic levitation high-speed motors have the advantages of high energy density, small structural size, and high efficiency. During the operation of magnetic levitation motors, the stability of the motor rotor is the key to ensuring the smooth and efficient operation of the motor. The long-term stable operation of the motor is the main purpose of the research. The axial stability of the motor rotor depends to a large extent on the precise positioning of the position sensor. The ability of the position sensor to work long-term and safely is one of the conditions that directly determines the working performance of the motor. Therefore, the development of a position sensor for high-speed magnetic levitation motors to enable the motor to operate efficiently and stably has become a technical problem that needs to be solved urgently.

[0003] The position sensor for the magnetic levitation motor is equipped with a coil, which is easily damaged. The current common solution is to pot it with epoxy resin. The traditional potting method is cumbersome, with low production efficiency and high production cost. There are several main methods for potting position sensors:

[0004] 1. Use a special demoulding mold for potting and demoulding. Usually, polytetrafluoroethylene, which is incompatible with epoxy resin, is used as the demoulding mold. After potting, the inner hole is processed to the required size. This method has cumbersome demoulding steps and requires processing the inner hole, which makes the operation process cumbersome and inefficient.

[0005] 2. Use a special vacuum potting box for potting. In a vacuum environment, the fluidity of epoxy resin is better, but this method requires a customized demoulding mold based on the position sensor, and can only pot 2-3 pieces at a time, which is inefficient. In addition, large vacuum potting boxes are expensive and difficult for general companies to afford. Summary of the Invention

[0006] The main technical problem to be solved by the present invention is to provide a position sensor for a high-speed magnetic levitation motor with a reasonable structure, a simple and efficient potting process and a reliable potting effect.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] A position sensor for a high-speed magnetic levitation motor includes a base, a mounting hole for a rotor to pass through is defined in the base, an inductor component and a circuit board are disposed in the mounting hole, an insulating component is disposed between the inductor component and the circuit board, the inductor component, the insulating component and the circuit board are fixedly connected to the base, a potting adhesive layer is potted in the mounting hole at positions surrounding the inductor component, the insulating component and the circuit board, and an annular gap is provided between the potting adhesive layer and the rotor.

[0009] The following is a further optimization of the above technical solution by the present invention:

[0010] The inductor assembly includes multiple silicon steel sheets, which are arranged in a ring shape around the axis of the mounting hole. Coils are wound around the silicon steel sheets, and the leads of the coils are welded to the circuit board. The surfaces of the circuit board and the coils are coated with an insulating paint layer.

[0011] Further optimization: the insulating assembly includes a plurality of insulating pads arranged corresponding to the plurality of silicon steel sheets, and the insulating pads are arranged between the circuit board and the corresponding silicon steel sheets.

[0012] The present invention also provides a potting method for a position sensor for a high-speed magnetic levitation motor. The potting method is based on the above-mentioned position sensor for a high-speed magnetic levitation motor and performs a potting operation on the position sensor. The operation steps are as follows:

[0013] A. Wind the coil on the silicon steel sheet. Fix the silicon steel sheet, circuit board and insulating pad on the base. Solder the coil lead to the circuit board.

[0014] B. Apply a layer of insulating varnish on the surface of the coil and circuit board, add dimethyl as a diluent to the insulating varnish, and then dry it in an oven;

[0015] C. Place the air plug inside the position sensor and inflate it through the air valve on the air plug. After the air plug is inflated, the outer circle of the air plug fits with the inner circle of the position sensor, forming an annular space between the base and the air plug.

[0016] D. Mix the epoxy resin and coagulant and stir them thoroughly to make the epoxy resin and coagulant fully blend;

[0017] E. Pour liquid epoxy resin into the annular space to completely fill it;

[0018] F. Place the potted position sensor in an oven for drying, and fix the base, silicon steel sheet, circuit board, and coil into a whole with epoxy resin;

[0019] G. Release the gas in the air plug and remove it from the position sensor. At this time, the epoxy resin used to pot the position sensor has solidified, and the silicon steel sheet, circuit board, and coil are wrapped in the solidified potting resin layer.

[0020] Further optimization: After the coil and circuit board are coated with insulating paint, they are placed in an oven and dried at a temperature of 103-107 degrees Celsius for 3 hours.

[0021] Further optimization: epoxy resin and coagulant are mixed in a weight ratio of 5:1.

[0022] Further optimization: The potted position sensor is placed in an oven for drying at a temperature of 50°C and for 3 hours.

[0023] The present invention improves the reliability of the position sensor through rational design by applying insulating paint and epoxy resin potting on the coil and circuit board; the air plug is easy to use and operate, does not require demoulding tooling, can be applied to position sensors of different specifications, and is suitable for large-scale assembly line operations.

[0024] The magnetic levitation motor position sensor and the motor rotor are assembled according to this installation method. The use of this material and process ensures uniform magnetic distribution, accurate positioning, and good stability. The advantages are: first, after the position sensor is encapsulated with epoxy resin, each coil is fixed as a whole, which greatly improves the vibration and impact resistance. The magnetic field is stable, which can effectively avoid the vibration of the motor rotor caused by the unstable magnetic field. This can ensure that the control system can accurately locate the rotor position, thereby making the rotor rotate stably and enhancing the stability of the motor operation.

[0025] The second is to use insulating varnish to treat the coil and circuit board before potting, and then potting epoxy resin on this basis, which improves the insulation performance of the position sensor and extends its service life. It will not cause the rotor to fall or be damaged due to sensor failure, ensuring long-term and safe operation of the motor.

[0026] The present invention will be further described below with reference to the accompanying drawings and examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the working structure of an embodiment of the present invention;

[0028] Figure 2 A schematic top view of the working structure of an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the potting state of an embodiment of the present invention;

[0030] Figure 4 Schematic diagram of the three-dimensional structure of an embodiment of the present invention.

[0031] In the figure: 1-base; 2-potting glue layer; 3-gap; 4-rotor; 5-silicon steel sheet; 6-circuit board; 7-coil; 8-bolt; 9-insulating pad; 10-air plug; 101-inflating valve. DETAILED DESCRIPTION

[0032] Example:

[0033] like Figure 1-4 As shown, a position sensor for a high-speed magnetic levitation motor includes a base 1, a mounting hole for a rotor 4 to pass through is opened in the base 1, an inductor component and a circuit board 6 are arranged in the mounting hole, an insulating component is arranged between the inductor component and the circuit board 6, the inductor component, the insulating component and the circuit board 6 are fixedly connected to the base 1 through a fixing component, a potting glue layer 2 is potted in the mounting hole at a position around the inductor component, the insulating component, the circuit board 6 and the fixing component, and a circular gap 3 is provided between the potting glue layer 2 and the rotor 4.

[0034] The inductor assembly includes a plurality of silicon steel sheets 5 , which are arranged in a ring shape around the axis of the mounting hole. A coil 7 is wound around the silicon steel sheet 5 , and the leads of the coil 7 are welded to the circuit board 6 .

[0035] The surfaces of the circuit board 6 and the coil 7 are coated with an insulating paint layer, thereby improving the insulation performance and moisture resistance of the position sensor, thereby increasing the service life of the position sensor.

[0036] The insulating paint composition is C32-58 various alkyd drying anti-arc paint. Dimethyl is added to the insulating paint as a diluent to increase the fluidity of the insulating paint, so that the insulating paint can be better applied on the surface of the circuit board 6 and the coil 7.

[0037] The insulating assembly includes a plurality of insulating pads 9 arranged corresponding to the plurality of silicon steel sheets 5 . The insulating pads 9 are arranged between the circuit board 6 and the corresponding silicon steel sheets 5 .

[0038] The insulating pad 9 is made of rubber, has a thickness of 1 mm, and can withstand a voltage of 1 kV.

[0039] The fixing assembly includes a plurality of bolts 8 arranged corresponding to the plurality of silicon steel sheets 5 . The bolts 8 are used to fix the circuit board 6 , the silicon steel sheets 5 and the insulating pads 9 to the base 1 .

[0040] With this design, the potting glue is potted around the circuit board 6, the silicon steel sheet 5, the coil 7 and the bolt 8, and forms a potting glue layer 2 after solidification, thereby improving the reliability of the position sensor.

[0041] The potting compound is a mixture of epoxy resin and coagulant with a weight ratio of 5:1. It has good fluidity and is in a solid state after solidification. The hardness is 85D (hardness unit). It also has good insulation and moisture resistance, further improving the reliability of the position sensor.

[0042] The present invention also provides a potting method for a position sensor for a high-speed magnetic levitation motor. The potting method performs potting operations based on the above-mentioned position sensor for a high-speed magnetic levitation motor.

[0043] The steps are as follows:

[0044] A. Wind the coil 7 on the silicon steel sheet 5. Fix the silicon steel sheet 5, circuit board 6 and insulation pad 9 to the base 1 through 8 bolts. Solder the lead wire of the coil 7 to the circuit board 6.

[0045] B. Apply a layer of insulating varnish on the surface of the coil 7 and the circuit board 6, add dimethyl as a diluent to the insulating varnish, and then place it in an oven to dry at a temperature of 103-107 degrees Celsius for 3 hours;

[0046] C. Place the air plug 10 inside the position sensor and inflate it through the inflation valve 101 on the air plug 10. The air plug 10 is made of high-temperature resistant rubber with a certain degree of elasticity and a temperature resistance of 300 degrees Celsius. After inflation, the air plug 10 expands. At this time, the air plug 10 is cylindrical, and the diameter D of the air plug 10 is larger than the diameter d of the rotor 4. The outer circle of the air plug 10 matches the inner circle of the position sensor, forming an annular space between the base 1 and the air plug 10.

[0047] D. Mix the epoxy resin and the coagulant in a weight ratio of 5:1 and stir thoroughly to fully blend the epoxy resin and the coagulant. At this time, the epoxy resin is in a liquid state with good fluidity;

[0048] E. Pour liquid epoxy resin into the annular space. The liquid epoxy resin has good fluidity and can completely fill the annular space.

[0049] F. Place the potted position sensor in an oven and dry it at 50°C for 3 hours. Epoxy resin can solidify the fastest at 50°C. After solidification, the epoxy resin is in a solid state. The base 1, silicon steel sheet 5, circuit board 6, and coil 7 are fixed into a whole by the epoxy resin.

[0050] G. Release the gas in the air plug 10 and remove the air plug 10 from the position sensor. At this time, the epoxy resin encapsulating the position sensor has solidified, and the silicon steel sheet 5, circuit board 6, and coil 7 are wrapped in the solidified encapsulating adhesive layer 2. The solidified epoxy resin is in a solid state with a hardness of 85D (hardness unit) and good insulation and moisture resistance, further improving the reliability of the position sensor.

[0051] For those skilled in the art, according to the teachings of the present invention, without departing from the principles and spirit of the present invention, changes, modifications, substitutions and variations made to the implementation methods are still within the scope of protection of the present invention.

Claims

1. A position sensor for a high-speed magnetic levitation motor, comprising a base (1), characterized in that: The base (1) is provided with a mounting hole for the rotor (4) to pass through, an inductor component and a circuit board (6) are provided in the mounting hole, an insulating component is provided between the inductor component and the circuit board (6), the inductor component, the insulating component and the circuit board (6) are fixedly connected to the base (1), a potting adhesive layer (2) is potted at a position around the inductor component, the insulating component and the circuit board (6) in the mounting hole, and a circular gap (3) is provided between the potting adhesive layer (2) and the rotor (4).

2. A position sensor for a high-speed magnetic levitation motor according to claim 1, characterized in that: The inductor assembly comprises a plurality of silicon steel sheets (5), the plurality of silicon steel sheets (5) being arranged in a ring shape around the axis of the mounting hole, a coil (7) being wound around the silicon steel sheets (5), a lead of the coil (7) being welded to a circuit board (6), and the surfaces of the circuit board (6) and the coil (7) being coated with an insulating paint layer.

3. A position sensor for a high-speed magnetic levitation motor according to claim 2, characterized in that: The insulating assembly comprises a plurality of insulating pads (9) arranged corresponding to the plurality of silicon steel sheets (5), and the insulating pads (9) are arranged between the circuit board (6) and the corresponding silicon steel sheets (5).

4. A potting method for a position sensor for a high-speed magnetic levitation motor, characterized in that: The potting method is based on the potting operation of the position sensor for the high-speed magnetic levitation motor according to claim 3, and the operation steps are as follows: The coil (7) is wound on the silicon steel sheet (5), the silicon steel sheet (5), the circuit board (6) and the insulating pad (9) are fixed on the base (1), and the lead wire of the coil (7) is welded on the circuit board (6); Apply a layer of insulating varnish on the surface of the coil (7) and the circuit board (6), add dimethyl as a diluent to the insulating varnish, and then place it in an oven for drying; The air plug (10) is placed in the position sensor, and then the air plug (10) is inflated through the inflation valve (101) on the air plug (10). After the air plug (10) is inflated, it expands, and the outer circle of the air plug (10) matches the inner circle of the position sensor, forming an annular space between the base (1) and the air plug (10); Mix the epoxy resin and the coagulant and stir them thoroughly to make the epoxy resin and the coagulant fully blend; Pour liquid epoxy resin into the annular space to completely fill it; The potted position sensor is placed in an oven for drying, and the base (1), silicon steel sheet (5), circuit board (6), and coil (7) are fixed into a whole by epoxy resin; The gas in the gas plug (10) is released, and the gas plug (10) is removed from the position sensor. At this time, the epoxy resin for encapsulating the position sensor has solidified, and the silicon steel sheet (5), the circuit board (6), and the coil (7) are wrapped by the solidified encapsulating adhesive layer (2).

5. The potting method for a position sensor for a high-speed magnetic levitation motor according to claim 4, characterized in that: The surfaces of the coil (7) and the circuit board (6) are coated with insulating paint and then placed in an oven for drying at a temperature of 103-107 degrees Celsius for 3 hours.

6. The potting method for a position sensor for a high-speed magnetic levitation motor according to claim 5, characterized in that: The epoxy resin and the solidifying agent were mixed in a weight ratio of 5:

1.

7. The potting method for a position sensor for a high-speed magnetic levitation motor according to claim 6, characterized in that: The potted position sensor is placed in an oven for drying at a temperature of 50° C. for 3 hours.

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