Back to results
US 3,956,938 AGranted
Pressure sensors utilizing ferromagnetic fluids
AssigneeThe Bendix Corporation
InventorJohn Paul Carrico
Life of this patent
Estimating the term…
Abstract
The invention is directed to the measurement of pressure and pressure differentials utilizing ferromagnetic fluids. The inventive devices include a ferromagnetic fluid physically arranged to be subjected to the pressure being monitored. Changes in the monitored pressure cause physical displacement of the ferromagnetic fluid. The displacements are detected by utilizing the magnetic characteristics of the ferromagnetic fluids to generate useful output signals.
Claims7
A fluid pressure sensor comprising:
- means for retaining a ferromagnetic fluid in the proximity of the pressure to be sensed, said ferromagnetic fluid being physicaly displaced in response to changes in said pressure to be sensed;
- means for sensing said displacement, said means for sensing being responsive to the magnetic characteristics of said ferromagnetic fluid to provide an output representative of said displacement;
- said means for retaining including a capillary, said ferromagnetic fluid extending into said capillary so that the level of said fluid within said capillary changes in response to changes in the pressure being sensed;
- and
- said means for sensing includes a coil positioned in the proximity of said level so that changes in said level change the permeability of said coil to produce a signal proportional to said displacement.
2 more elements
A fluid pressure sensor comprising:
- means for retaining a ferromagnetic fluid in the proximity of the pressure to be sensed, said ferromagnetic fluid being physically displaced in response to changes in said pressure to be sensed;
- means for sensing said displacement, said means for sensing being responsive to the magnetic characteristics of said ferromagnetic fluid to provide an output representative of said displacement;
- and
- a ring magnet, said ferromagnetic fluid being located within said ring magnet and being magnetically held by said ring magnet.
1 more element
A fluid pressure sensor comprising:
- means for retaining a ferromagnetic fluid in the proximity of the pressure to be sensed, said ferromagnetic fluid being physically displaced in response to changes in said pressure to be sensed, said means for retaining being a magnet having an aperture, said ferromagnetic fluid being held in said aperture and having a protrusion extending past said magnet, so that said protrusion responds to the motion of an element in contact therewith;
- means for sensing said displacement, said means for sensing being responsive to the magnetic characteristics of said ferromagnetic fluid to provide an output representative of said displacement.
Dependencies are inferred from the claim text.