Sensitive differential pressure sensor and method
US8375801B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 20, 2010 |
| Grant date | Feb 19, 2013 |
| Priority date | — |
| Expiry date | Aug 17, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L13/06
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A differential pressure sensor has a magnetized piston free to move in a cylinder. Magnetic endcaps seal the ends of the cylinder, forming chambers on either side of the piston. The moveable magnetic piston is constrained by the opposing magnetic fields of the endcaps. The piston is covered with magnetic ferrofluid, providing a low friction gas-tight seal around the piston. The cylinder has two pressure input lines, one being connected to the chamber on either side of the piston. The relative pressures of the input lines cause the piston to move to a position of equilibrium within the cylinder, with the magnetic fields of the endcaps holding the piston in place against the pressure. A magnetic field angle sensor detects flux lines on the outside of the cylinder, and the reading is correlated with the pressure differential between the two input lines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.