Magnetorheological fluid-based device and method for use

Patent metadata

Field	Value
Publication number	US-9016318-B2
Application number	US-201213357055-A
Country	US
Kind code	B2
Filing date	Jan 24, 2012
Priority date	Jan 24, 2012
Publication date	Apr 28, 2015
Grant date	Apr 28, 2015

Abstract

A magnetorheological fluid-based device and method may include the use of magnetorheological (MR) fluid, a primary magnetic field to control the viscosity of the fluid, and a secondary magnetic field to reduce clumping of ferromagnetic particles.

First claim

What is claimed is:

1. A magnetorheological device comprising,
a magnetorheological fluid disposed in a conduit, the magnetorheological fluid comprising ferromagnetic particles in a carrier liquid;
a controllable magnetic field generator configured to apply a primary magnetic field to the magnetorheological fluid so as to modulate its viscosity
an array of magnetic regions permanently magnetized into a single body of ferromagnetic material, the array configured to apply a secondary magnetic field to the magnetorheological fluid so as to maintain the ferromagnetic particles in a fibril-free suspension in an absence of the primary magnetic field.

2. The magnetorheological fluid-based device of claim 1 , wherein the carrier fluid includes oil or water.

3. The magnetorheological device of claim 2 , wherein the array includes a regular pattern of magnetic regions in alternating polarizations.

4. The magnetorheological device of claim 2 , wherein the array includes at least two magnetic regions of different magnetic strengths.

5. The magnetorheological device of claim 1 , further comprising a processor configured to control the magnetic field generator.

6. A method of maintaining responsiveness of a magnetorheological device comprising:
providing a magnetorheological device having controllable magnetic field generator configured to apply a primary magnetic field to a magnetorheological liquid disposed in the device, the magnetorheological liquid having ferromagnetic particles disposed in a carrier liquid; and
using an array of an array of magnetic regions permanently discrete magnetic regions permanently magnetized into a single body of ferromagnetic material to apply a secondary magnetic field to the magnetorheological liquid fluid so as to maintain the ferromagnetic particles in fibril-free suspension in an absence of the primary magnetic field.

7. The method of claim 6 , wherein the carrier liquid includes oil or water.

8. The method of claim 7 , wherein the array includes a regular pattern of magnetic regions in alternating polarizations.

9. The method of claim 7 , wherein the array includes at least two magnetic regions of different magnetic strengths.

Assignees

• Mankame Nilesh D
• Browne Alan L
• Ulicny John C
• Gm Global Tech Operations Inc

Inventors

• Mankame Nilesh D
• Browne Alan L
• Ulicny John C

Classifications

• F16F13/305 Primary

  magnetorheological · CPC title

• Y10S137/909

  Magnetic fluid valve · CPC title

• F16F9/537

  specially adapted valves therefor · CPC title

• F15B21/065 Primary

  Use of electro- or magnetosensitive fluids, e.g. electrorheological fluid · CPC title

• Y10T137/2082

  Utilizing particular fluid · CPC title