CN102954004A - Double-cage rotor magnetic pump - Google Patents

Abstract

The invention relates to the technical field of electromagnetic power, and provides a double-cage rotor magnetic pump, which includes a motor, a pump body, a housing, an input shaft, and an output shaft. The input shaft is rotatably arranged on one side of the housing, and the first end of the input shaft In the housing, the second end of the input shaft is outside the housing, the output shaft is rotatably arranged on the pump body, the first end of the output shaft is in the housing, the second end of the output shaft is in the pump body, and the first end of the input shaft A cup-shaped sleeve is arranged on the end, and an annular outer magnetic rotor core is arranged on the inner edge of the cup-shaped sleeve; an annular bushing is arranged on the first end of the output shaft, and an annular inner rotor core is arranged outside the annular bushing. An outer magnetic rotor magnet ring is arranged on the inner wall of the rotor core, and an upper and lower squirrel cage is arranged on the annular inner rotor core. The inner rotor iron core and the upper and lower squirrel cages constitute the inner rotor, and an annular gap is formed between the outer magnetic rotor magnet ring and the inner rotor. The technical scheme of the invention makes the magnetic density of the air gap a sinusoidal waveform, which reduces the harmonic loss generated by the iron core.

Description

Double cage rotor magnetic pump

technical field

The invention relates to the technical field of electromagnetic power, in particular to a double-cage rotor magnetic pump.

Background technique

The magnetic pump is a kind of pump in which the outer magnetic rotor and the inner rotor cooperate to drive the inner rotor to rotate through magnetic force, and the inner rotor drives the pump shaft to rotate, so that the impeller rotor on the pump shaft in the pump body rotates to work. Generally, the inner and outer magnetic rotors are excited by permanent magnets, and have the same number of pole pairs, and the speed driven by the motor is the same as the speed of the impeller. The magnetic pump is compact in structure, beautiful in appearance, small in size, low in noise, and reliable in operation. Pumping of flammable and explosive liquids.

In order to prevent demagnetization of the inner rotor, the inner rotor is generally designed using the operating principle of an induction motor. The widely used asynchronous motor is simple in structure, strong and durable, easy to manufacture, low in cost and excellent in performance. Its working principle is that the rotating air-gap magnetic field cuts the rotor conductor, and an induced potential is generated in it. Since the rotor winding is short-circuited, a current flows in the rotor conductor, and the current in the rotor conductor interacts with the air-gap magnetic field to generate electromagnetic force. Torque, which is in the same direction as the rotating magnetic field. The asynchronous motor adopts measures such as short-distance winding, distributed winding, and chute to make the main magnetic field in the air gap sinusoidally distributed. It is difficult to realize the sinusoidal air-gap magnetic field drive for the magnetic pumps with radial magnetization and parallel magnetization that are currently used. In addition, the existing magnetic drive pumps cannot meet the coordination of different starting and working performances, and cannot meet the requirements of various loads. the

Contents of the invention

The object of the present invention is to solve the above technical problems and provide a double-cage rotor magnetic pump in order to realize the sinusoidal air gap magnetic field drive of the magnetic pump.

The technical scheme that the present invention takes is:

A double-cage rotor magnetic pump, comprising a motor, a pump body, a casing, an input shaft, and an output shaft, the casing is installed on one side of the pump body, and the input shaft is rotatably arranged on the casing away from the pump One side of the body, the first end of the input shaft is inside the housing, the second end of the input shaft is outside the housing, the second end of the input shaft is used to connect the motor, and the output shaft It is rotatably arranged on the pump body, the first end of the output shaft is in the casing, the second end of the output shaft is in the pump body, and the second end of the output shaft is used to install the magnetic pump For the impeller, a cup-shaped sleeve is arranged on the first end of the input shaft, an annular outer magnetic rotor core is arranged on the inner edge of the cup-shaped sleeve; an annular sleeve is arranged on the first end of the output shaft, An annular inner rotor core is arranged outside the annular shaft sleeve, and it is characterized in that an outer magnetic rotor magnet ring is arranged on the inner wall of the annular outer magnetic rotor core, and a lower squirrel cage is arranged on the annular inner rotor core, The upper squirrel cage is arranged on the lower squirrel cage, the inner rotor core and the upper and lower squirrel cages form the inner rotor, and an annular gap is formed between the magnet ring of the outer magnetic rotor and the inner rotor.

Further, the outer magnetic rotor magnet ring is composed of an even number of permanent magnets, and the polarities of two adjacent permanent magnets are different.

Further, each of the permanent magnets is composed of several Halbach magnets, and the magnetic field formed by several Halbach magnets converges toward the inner side of the cup-shaped sleeve and diverges toward the outer side of the cup-shaped sleeve.

Further, an isolation cover is set in the annular gap, the isolation cover is fixed on the pump body, and the annular inner rotor core and upper and lower squirrel cages are sealed in the isolation cover.

Further, the material of the upper cage is brass or bronze, and the material of the lower cage is copper.

Further, the input shaft is arranged coaxially with the output shaft.

The beneficial effects of the present invention are:

1. Compared with the traditional magnetic pump, the outer magnetic rotor magnet structure is a Habach structure, and the air gap magnetic density is a sinusoidal waveform. The harmonics that do not participate in the torque transmission in the sinusoidal drive magnetic field are small, thereby reducing the generation of harmonics by the core losses, harmonic currents in conductors;

2. The inner induction rotor is a double-cage structure, the upper cage is the starting cage, and the lower cage is the working cage, which can generate a large starting torque, reduce the starting time, and quickly enter the working state;

3. When the high-temperature medium flows, there is no problem of demagnetization of the inner rotor;

4. Short-time overload is allowed;

5. Compared with the magnetic transmission device with a spacer sleeve on the rotor of the asynchronous machine, since the permanent magnet is used for excitation, the reactive current of the power grid is not required.

Description of drawings

Accompanying drawing 1 is a structural representation of the present invention;

Accompanying drawing 2 is A-A sectional view in accompanying drawing 1;

Accompanying drawing 3 is the schematic diagram of the Halbach magnet structure of the outer rotor.

The marks in the accompanying drawings are:

1. Pump body; 2. impeller;

3. Housing; 4. end cap;

5. Cup-shaped sleeve; 6. Outer magnetic rotor core;

7. External magnetic rotor magnet ring; 8. Isolation sleeve;

9. Go to the mouse cage; 10. lower mouse cage;

11. Inner induction rotor core; 12. inner shaft sleeve;

13. Input shaft; 14. Output shaft;

15. Couplings; 16. electric motor.

Detailed ways

The specific implementation of the double-cage rotor magnetic drive pump of the present invention will be described in detail below in conjunction with the accompanying drawings.

Referring to accompanying drawings 1, 2, and 3, the double-cage rotor magnetic pump includes a pump body 1 and a casing 3. The casing 3 is installed on one side of the pump body 1, and a bearing seat is provided on one side of the casing 3. On the bearing The input shaft 13 is set through a bearing in the seat. In order to facilitate processing, one side of the housing 3 is an encapsulated end cover 4. The bearing seat is arranged on the end cover 4. The first end of the input shaft 13 is located inside the housing 3. The input shaft The second end of 13 is connected on the rotating shaft of electric motor 16 by coupling 15. The output shaft 14 is installed on the pump body 1 through bearing rotation, the first end of the output shaft 14 extends into the casing 3, the second end of the output shaft 14 extends into the pump body 1, and the second end of the output shaft 14 is used for The impeller 2 of the magnetic pump is installed, and the input shaft 13 and the output shaft 14 can be arranged coaxially. A cup-shaped sleeve 5 is arranged on the first end of the input shaft 13, an annular outer magnetic rotor core 6 is arranged on the inner edge of the cup-shaped sleeve 5, and an outer magnetic rotor magnet is arranged on the inner wall of the annular outer magnetic rotor iron core 6 ring 7, an annular shaft sleeve 12 is arranged at the first end of the output shaft 14, an annular inner rotor core 11 is arranged outside the annular shaft sleeve 12, a lower squirrel cage 10 is arranged on the annular inner rotor iron core 11, and a lower squirrel cage 10 is arranged The upper squirrel cage 9, the inner rotor iron core 11 and the upper and lower squirrel cages 9, 10 constitute the inner rotor, and an annular gap is formed between the outer magnetic rotor magnet ring 7 and the inner rotor. An isolation cover 8 is installed between the annular gaps, the isolation cover 8 is fixed on the pump body 1, and the annular inner rotor core 11 and the upper and lower squirrel cages 9, 10 are sealed in the isolation cover 8. The outer magnetic rotor magnet ring 7 is composed of even number 2P (P is a natural number) permanent magnets installed evenly in the circumferential direction of the inner wall of the outer magnetic rotor iron core 6. The polarities of the two adjacent permanent magnets are different, so that a total of P pairs of permanent magnet poles are formed. Each magnetic pole is composed of several Halbach magnet arrays with an inward magnetic field. The inward magnetic field is a magnetic field that converges inward and diverges outward. The two squirrel cages installed on the inner induction rotor core 11, the upper squirrel cage 9 is a starting cage, the lower squirrel cage 10 is a working cage, the upper squirrel cage 9 is usually made of materials with high resistivity such as brass and bronze, and the lower squirrel cage 9 is a working cage. The cross section of the guide bar of the squirrel cage 10 is larger, and is made of red copper with lower resistivity. An inner layer air gap is formed between the inner induction rotor and the isolation cover 8 , and an outer layer air gap is formed between the outer magnetic rotor and the isolation cover 8 . There is an isolation cover 8 between the inner induction rotor and the outer magnetic rotor to form a sealed cavity, which seals the output shaft 14 and the inner induction rotor in the sealed cavity, which not only prevents fluid from leaking to the outside, but also cools the magnetic transmission device.

Referring to accompanying drawing 3, each permanent magnet pole of the outer rotor magnet ring 7 uses n pieces of magnets, the magnetization intensity of each piece of magnets is M, the number of pole pairs is p, and the magnetization direction of the first piece of magnets is positive along the x axis direction, then the magnetization x and y components of the i-th magnet in the Halbach magnet structure are expressed as follows:

。

.

By changing the size of the upper and lower cages 9 and 10 installed on the inner induction rotor core 11, the material and the gap size between the upper and lower cages, the resistance and leakage reactance parameters of the upper and lower cages can be changed, thereby Get different start and work performance fits. The inner induction rotor and the outer magnetic rotor rotate in the same direction, and the speed is lower than that of the outer magnetic rotor, and the difference between the two is the slip.

See attached drawing 3, the Halbach magnet structure of the outer magnetic rotor is used to generate a sinusoidal driving magnetic field, and each magnetic pole is composed of several (3 in this figure) Halbach magnet arrays with inward magnetic fields, and the magnetic fields converge inwardly and outwardly divergent in direction.

The working process of the present invention is that the rotating Halbach magnet structure is used to generate a sinusoidal drive magnetic field, which cuts the conductor of the squirrel cage and generates an induced potential therein. Since the conductor of the squirrel cage is short-circuited, there is When the current flows, the current in the conductor of the squirrel cage interacts with the magnetic field to generate electromagnetic torque, which is in the same direction as the rotating magnetic field, driving the inner rotor to rotate, so that the output shaft drives the impeller to rotate.

The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications should also be considered Be the protection scope of the present invention.

Claims (6)

1. A magnetic pump with double cage rotors, comprising a motor, a pump body, a casing, an input shaft, and an output shaft, the casing is installed on one side of the pump body, and the input shaft is rotatably arranged on the casing On the side away from the pump body, the first end of the input shaft is inside the housing, the second end of the input shaft is outside the housing, and the second end of the input shaft is used to connect to the motor. The output shaft is rotatably arranged on the pump body, the first end of the output shaft is in the housing, the second end of the output shaft is in the pump body, and the second end of the output shaft is used to install the magnetic force For the impeller of the pump, a cup-shaped sleeve is arranged on the first end of the input shaft, an annular outer magnetic rotor core is arranged on the inner edge of the cup-shaped sleeve; an annular shaft is arranged on the first end of the output shaft Set an annular inner rotor core outside the annular shaft sleeve, and it is characterized in that: an outer magnetic rotor magnet ring is arranged on the inner wall of the annular outer magnetic rotor core, and a lower mouse is arranged on the annular inner rotor core. An upper squirrel cage is arranged on the lower squirrel cage, the inner rotor core and the upper and lower squirrel cages constitute the inner rotor, and an annular gap is formed between the magnet ring of the outer magnetic rotor and the inner rotor. 2. The double-cage rotor magnetic drive pump according to claim 1, characterized in that: the outer magnetic rotor magnet ring is composed of an even number of permanent magnets, and the polarities of two adjacent permanent magnets are different. 3. The double-cage rotor magnetic pump according to claim 2, characterized in that: each of the permanent magnets is composed of several Halbach magnets, and the magnetic field formed by several Halbach magnets aggregates towards the inner side of the cup-shaped sleeve. The outer direction of the shaped sleeve diverges. 4. The double-cage rotor magnetic pump according to any one of claims 1 to 3, characterized in that: an isolation cover is set in the annular gap, the isolation cover is fixed on the pump body, the The annular inner rotor core and the upper and lower squirrel cages are sealed in the isolation cover. 5. The double-cage rotor magnetic pump according to any one of claims 1 to 3, characterized in that: the material of the upper squirrel cage is brass or bronze, and the material of the lower squirrel cage is copper. 6. The double-cage rotor magnetic pump according to any one of claims 1 to 3, wherein the input shaft and the output shaft are arranged coaxially.

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