Housing for magnetofluidic accelerometer

• US 20050193801A1
• Filed: 12/14/2004
• Published: 09/08/2005
• Est. Priority Date: 03/03/2004
• Status: Active Grant

• Current Assignee: InnaLabs Limited
• Original Assignee: InnaLabs Technologies, Inc.
• Inventors: Simonenko, Dmitri V., Suprun, Anton E., Romanov, Yuri I.
• Granted Patent: US 7,178,399 B2
• Time in Patent Office: Days
• US Class Current: 73/1.37
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: G01P 15/0888 for indicating angular acceleration
• CPC Class Codes: G01P 15/105 by magnetically sensitive devices
• CPC Class Codes: G01P 15/11 by inductive pick-up
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

A housing for a magnetofluidic sensor where the sensor has a plurality of drive magnet assemblies, magnetic fluid and an inertial body. The housing has a plurality of ports for securing respective drive magnet assemblies, such that a portion of each drive magnet assembly is positioned within the housing proximate the magnetic fluid. Each drive magnet assembly includes a magnetic field source for creating a magnetic field within the magnetic fluid for acting upon the inertial body. Each drive magnet assembly also includes a sensing element for sensing movement of the inertial body within the magnetic fluid.

Claims

1. A magnetofluidic acceleration sensor comprising:

a housing having a plurality of ports that provide an opening from an exterior to an interior of the housing;

a plurality of drive magnet assemblies, each drive magnet assembly engageable with a respective port of the housing, wherein each drive magnet assembly includes a magnetic field source;

a magnetic fluid within the housing; and

an inertial body within the magnetic fluid.

2. The sensor of claim 1, wherein each drive magnet assembly further includes a sensing element.

3. The sensor of claim 1, wherein each drive magnet assembly further includes an assembly casing and a rear cap that fit together to substantially enclose the magnetic field source and the sensing element.

4. The sensor of claim 3, wherein the magnetic field source includes a drive magnet coil and the sensing element includes a pair of sensing coils.

5. The sensor of claim 4, wherein the drive magnet coil and the pair of sensing coils are wound about a common transformer core.

6. The sensor of claim 5, wherein the common transformer core is engageable with the rear cap of the drive magnet assembly.

7. The sensor of claim 3, wherein each assembly casing has a plurality of inclined surfaces that extend within the interior of the housing.

8. The sensor of claim 7, wherein the inclined surfaces of one drive magnet assembly align with the inclined surfaces of proximate drive magnet assemblies.

9. The sensor of claim 3, wherein each assembly casing includes a leading surface such that the leading surfaces of the drive magnet assemblies form a working space within which the inertial body is contained.

10. The sensor of claim 3, wherein each assembly casing includes a leading surface.

11. The sensor of claim 10, wherein the sensing element includes a pair of sensing coils wound about a respective core portion, such that a leading surface of the core portions and a leading surface of the assembly casing are in a common plane.

12. The sensor of claim 11, wherein a hermetic seal is used to seal the leading surfaces of the core portions and the assembly casing to prevent magnetic fluid from entering the assembly casing.

13. The sensor of claim 1, wherein the housing has six sides, with each side having one of the plurality of drive magnet assemblies attached thereto.

14. The sensor of claim 1, wherein the housing has six sides with fewer than all sides having one of the plurality of drive magnet assemblies attached thereto.

15. The sensor of claim 14, wherein the housing includes contact pads on at least one side of the housing for engaging with a printed circuit board.

16. The sensor of claim 1, wherein the magnetic field source is a drive magnet selected from a group consisting essentially of a magnet, an electromagnet and a combination of a magnet and an electromagnet.

17. The sensor of claim 1, wherein the inertial body is non-magnetic.

18. A sensor comprising:

a housing;

a plurality of drive magnet assembly positioned within the housing, wherein each drive magnet assembly includes a magnet;

a magnetic fluid within the housing proximate to the drive magnet; and

an inertial body within the magnetic fluid.

19. The sensor of claim 18, further comprising:

a sensing element that senses movement of the inertial body.

20. The sensor of claim 18, wherein the housing further includes a first joining surface of a first housing portion being securable to a corresponding second joining surface of a second housing portion to form the housing.

21. The sensor of claim 20, wherein the first and second joining surfaces are inclined relative to a horizontal axis.

22. The sensor of claim 20, wherein each of the first and second housing portions includes a half of a working space for housing the inertial body and the magnetic fluid.

23. The sensor of claim 20, wherein each of the first and second housing portions includes at least one drive magnet assembly.