Device sealed with magnetic liquid

Patent metadata

Field	Value
Publication number	US-12444527-B2
Application number	US-202318496477-A
Country	US
Kind code	B2
Filing date	Oct 27, 2023
Priority date	Oct 31, 2022
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

Provided is a device sealed with a magnetic liquid. The device includes: a rotary shaft, a tank body, a control unit, a first module, a second module, a magnetic liquid, and a pole-tooth. The first module and the second module are in the same configuration, each consists of an outer shell, a left pole-shoe, an electromagnet, a control wiring, a right pole-shoe, and a circlip. The device includes at least two modular structures; the control unit controls a first electromagnet and a second electromagnet to be magnetized to alternately bear a sealing role.

First claim

What is claimed is:

1. A device sealed with a magnetic liquid, the device comprising: a rotary shaft, a tank body, a control unit a first module, a second module, a magnetic liquid, and a pole-tooth,
wherein the first module consists of a first outer shell, a first left pole-shoe, a first electromagnet, a first control wiring, a first right pole-shoe, and a first circlip; and the second module consists of a second left pole-shoe, a second control wiring, a second electromagnet, a second right pole-shoe, a second outer shell, and a second circlip,
wherein the first left pole-shoe, the first right pole-shoe, the second left pole-shoe, and the second right pole-shoe each are provided with a gasket ring in a circular groove located at respective exterior circumferential surfaces; and the first left pole-shoe, the first right pole-shoe, the second left pole-shoe, and the second right pole-shoe each are provided with a plurality of pole-teeth at respective interior circumferential surfaces,
wherein the first left pole-shoe and the first electromagnet are installed in the first outer shell; the first control wiring has a first end connected to the first electromagnet through a first through-hole arranged in the first outer shell; the first right pole-shoe and the first circlip are installed in the first outer shell; and the first through-hole through which the first control wiring passes the first outer shell is sealed with a sealant,
wherein the second left pole-shoe and the second electromagnet are installed in the second outer shell; the second control wiring has a second end connected to the second electromagnet through a second through-hole arranged in the second outer shell; the second right pole-shoe and the second circlip are installed in the second outer shell; and the second through-hole through which the second control wiring passes the second outer shell is sealed with the sealant,
wherein the first module is installed at the tank body by bolt connection; the first control wiring has a third end connected to the control unit; the control unit is configured to provide a first electric current for magnetizing the first electromagnet in a first direction; the magnetic liquid is injected into a first space to be sealed between the first left pole-shoe, the first right pole-shoe and an exterior circumferential surface of the rotary shaft,
wherein the second module is installed at the first module by bolt connection; the second control wiring has a fourth end connected to the control unit; the control unit is configure to provide a second electric current for magnetizing the second electromagnet in a second direction; the magnetic liquid is injected into a second space to be sealed between the second left pole-shoe, the second right pole-shoe and the exterior circumferential surface of the rotary shaft,
wherein based on the first direction is an axial direction and the second direction is a radial direction, the magnetic liquid gathers:
in the first space, between respective interior circumferential surfaces of the first left pole-shoe and the first right pole-shoe at the plurality of pole-teeth and the exterior circumferential surface of the rotary shaft, for sealing; and
between the second left pole-shoe and the second right pole-shoe away from the rotary shaft and near the second electromagnet, allowing for cooling and heat dissipating,

wherein based on the first direction is the radial direction and the second direction is the axial direction, the magnetic liquid gathers:
between the first left pole-shoe and the first right pole-shoe away from the rotary shaft and near the first electromagnet, allowing for cooling and heat dissipating; and
in the second space, between respective interior circumferential surfaces of the second left pole-shoe and the second right pole-shoe at the plurality of pole-teeth and the exterior circumferential surface of the rotary shaft, for sealing,

wherein at least one of the first direction and the second direction is the axial direction.

2. The device sealed with a magnetic liquid according to claim 1 , wherein:
the first module and the second module are in the same configuration; and
the device comprises at least the first module and the second module both.

3. The device sealed with a magnetic liquid according to claim 1 , wherein the rotary shaft, the first left pole-shoe, the first right pole-shoe, the second left pole-shoe, and the second right pole-shoe each are made of 2Cr13; and the tank body, the first outer shell, and the second outer shell each are made of a non-permeability magnetic material.

Assignees

• Univ Beijing Jiaotong
• Univ Tsinghua

Inventors

• Li Decai
• Wang Zhibin
• Liu Sijia
• He Xinzhi

Classifications

• H01F1/44 Primary

  of magnetic liquids, e.g. ferrofluids (particles in a bonding agent H01F1/28, H01F1/36, {H01F1/37}) · CPC title

• H01F7/20 Primary

  without armatures (cores H01F3/00; coils H01F5/00 {; shaping metal by applying magnetic forces B21D26/14; electromagnets specially adapted for NMR applications G01R33/381}) · CPC title