CN-115614479-B - Magnetic fluid seal using stator winding type pole shoe

Abstract

The invention relates to a magnetic fluid seal using a stator winding type pole shoe, which comprises a shell, a stator type pole shoe ring, a winding coil and a rotating shaft. The motor stator winding structure is applied to magnetic liquid sealing, the size of a sealing gap magnetic field is adjusted by adjusting the current of a winding coil, and the problems of difficult magnetization, difficult processing, easy demagnetization and uncontrollable magnetic field of a permanent magnet commonly used for magnetic liquid sealing are solved.

Inventors

• LIU JIAWEI
• LI DECAI
• LIU SIJIA

Assignees

• 北京交通大学
• 清华大学

Dates

Publication Date

20260512

Application Date

20220908

Claims (5)

1. 1. A magnetic fluid seal using a stator winding type pole shoe comprises a shaft (1), a magnetic conduction ring (2), stator pole shoe rings (3), a non-magnetic conduction ring (4), winding coils (5) and a shell (7), and is characterized in that the magnetic conduction ring (2) and the stator pole shoe rings (3) are arranged on the inner wall of the shell (7), a gap is reserved between the inner circular surface of the stator pole shoe rings (3) and the outer circular surface of the shaft (1), the non-magnetic conduction ring (4) is arranged between the two stator pole shoe rings (3), pole teeth are arranged on the outer circular surface of the shaft (1) and extend to the inner circular surface of the stator pole shoe rings (3) along the radial direction, gaps are reserved between the pole teeth and the stator pole shoe rings, magnetic fluid is filled in the gaps, a magnetic field which is uniform along the circumferential direction is formed between the outer circular surface of the shaft (1) and the inner circular surface of the stator pole shoe rings (3), a plurality of pole phase slots (8) are formed along the axial direction, the minimum distance between the minimum diameter of the pole phase slots (8) and the outer circular surface of the shaft (1) is 0.05 mm, the number of the pole slots and the stator pole shoe rings (3) are embedded in the winding ring structures, and the winding ring structures are embedded in the winding ring structures (3) and the winding structures are 3.
2. 2. A magnetic fluid seal using stator winding type pole shoes as claimed in claim 1, characterized in that the number of pole teeth arranged on the outer circular surface of the shaft (1) is 2-20.
3. 3. A magnetic fluid seal using stator winding type pole shoes as claimed in claim 1, wherein the gap between the outer circular surface of the pole teeth of the shaft (1) and the inner circular surface of the stator pole shoe ring (3) is 0.05-3 mm.
4. 4. A magnetic fluid seal using stator winding type pole shoe as set forth in claim 1, wherein the winding coil (5) is copper wire covered by lacquer, direct current power is used for supplying power, the windings in different pole shoe rings are electrified with direct current with opposite directions, and a magnetic field is excited at the center of the winding coil to enter the iron core of the other winding coil through the iron core and the shaft of the stator type pole shoe ring to form a magnetic loop.
5. 5. The magnetic fluid seal using the stator winding type pole shoe as claimed in claim 1, wherein the total number of phase slots of each phase pole of the stator core of the stator pole shoe ring (3) is even, and a sealing ring groove (6) is arranged on the outer circular surface of the stator pole shoe ring (3).

Description

Magnetic fluid seal using stator winding type pole shoe Technical Field The invention belongs to the field of mechanical engineering sealing, and particularly relates to a magnetic fluid seal using a stator winding type pole shoe. Background The magnetic fluid seal is to firmly fix the magnetic fluid in the sealing gap by utilizing the magnetic force generated by the permanent magnet in the sealing gap to resist the pressure difference at two sides, thereby achieving the sealing effect. The permanent magnet commonly used for magnetic liquid sealing is generally sintered neodymium iron boron material, which is a brittle and hard material difficult to process, after the structure is determined, the magnetic field generated by the permanent magnet is not controllable, and the permanent magnet has serious demagnetization problem in extreme environment, so that the pressure resistance and the sealing stability are affected. Under the conditions of standing and steady-state magnetic fields, although the columnar structure of the magnetic particles at the sealing gap can improve the pressure resistance, the pressure resistance of the magnetic liquid seal under the static seal can be increased along with the time, but the starting torque under the dynamic seal is obviously increased, the starting of the sealing main shaft is seriously hindered, and once the sealing main shaft is forcedly started, the improvement of the pressure resistance increased by the columnar structure formed by the magnetic liquid particles can disappear, so that the existence of the columnar structure of the magnetic particles under the application of the dynamic seal is characterized by the defects of large starting moment, inaccurate pressure resistance and the like, and the significance is low and the situation is avoided. Disclosure of Invention The invention aims to provide a magnetic fluid sealing device using stator winding type pole shoes, wherein a motor stator winding structure is applied to magnetic liquid sealing, and the size of a sealing gap magnetic field is adjusted by adjusting the current of a winding coil, so that the problems of high magnetic liquid sealing starting torque, inaccurate pressure resistance, difficult magnetization, difficult processing, easy demagnetization and uncontrollable magnetic field of a permanent magnet are solved. The patent carries out finite element simulation aiming at a large number of magnetic liquid sealing examples, analyzes simulation results, and provides a reasonable design scheme of magnetic fluid sealing by using stator winding type pole shoes. The magnetic fluid seal using the stator winding type pole shoe comprises a shaft, a magnetic conduction ring, stator type pole shoe rings, a non-magnetic conduction ring, winding coils and a shell, and is characterized in that the magnetic conduction ring and the stator type pole shoe rings are arranged on the inner wall of the shell, a gap is reserved between the inner circular surface of each stator type pole shoe ring and the outer circular surface of the shaft, the non-magnetic conduction ring is arranged between the two stator type pole shoe rings, pole teeth are arranged on the outer circular surface of the shaft, extend radially to the inner circular surface of each stator type pole shoe ring, a gap is reserved between the pole teeth and the stator type pole shoe rings, the gap is filled with magnetic fluid for sealing, a magnetic field which is uniform along the circumferential direction is formed in the gap between the outer circular surface of the shaft and the inner circular surface of each stator type pole shoe ring, a plurality of pole phase grooves are formed in the stator core, the distance between the minimum positions of the pole phase grooves and the outer circular surface of the shaft is 0.05-3 mm, the coils are embedded into the pole phase grooves by adopting a groove embedding line structure, the number of the inner grooves is 12-36, and the pole phase grooves of the stator type pole shoe rings are installed together with the magnetic conduction rings after wiring of the winding coils is completed. The magnetic fluid seal using the stator winding type pole shoe is characterized in that the number of pole teeth on the outer circular surface of the shaft is 2-20. The magnetic fluid seal using the stator winding type pole shoe is characterized in that the size of a gap between the outer circular surface of the pole tooth of the shaft and the inner circular surface of the stator type pole shoe ring (3) is 0.05-3 mm. The magnetic fluid seal is characterized in that the winding coil is copper wire covered by paint, a direct current power supply is used for supplying power, the windings in different pole shoe rings are electrified with direct current with opposite directions, and a magnetic field is excited at the center of the winding coil and enters the center of the other winding coil through the magnetic conduction pole shoe a