Ferraris sensor

US7082829B2 · kind B2 · utility

Assignee

• DR. JOHANNES HEIDENHAIN GMBH · DE

Inventors

• Michael Schwabe · Rimsting, DE
• Ralph Schmidt · Raubling, DE
• Lutz Rissing · Seebruck, DE

Key dates

• Filing date: May 7, 2002
• Grant date: Aug 1, 2006
• Expiry date: May 7, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G01P15/16
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A Ferraris sensor for measuring an acceleration of a moving body along a direction. The sensor includes a flat eddy current body and a scanning head arranged on one side of the eddy current body. The scanning head includes N magnets that generate an external magnetic field that extends approximately perpendicular to a surface of the eddy current body, wherein N=1, 2, 3, . . . and M detector coils, wherein M=1, 2, 3, 4, . . . and each detector coil includes an axis and detects changes of an interior magnetic field within the N magnets that are caused by an acceleration of the eddy current body and a resulting change in eddy currents. The axis is approximately perpendicular with respect to the surface of the eddy current body, each detector coil lacks a ferromagnetic core and the N magnets and the M detector coils are arranged alternatingly next to each other in a direction that the acceleration is to be measured.