Micromechanical rpm sensor

US6490923B1 · kind B1 · utility

Assignee

• LITEF GmbH · DE

Inventors

• Uwe Breng · Gundelfingen, DE
• Martin Hafen · Colmar, FR
• Eberhard Handrich · Kirchzarten, DE
• Bruno Ryrko · Denzlingen, DE

Key dates

• Filing date: Dec 14, 2000
• Grant date: Dec 10, 2002
• Expiry date: Dec 14, 2020

Classification

• Technology area (CPC G): Physics
• CPC primary: G01C19/5656
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A micromechanical rotation rate sensor based on the Coriolis principle includes two plate-like oscillators arranged one above the other in two planes for excitation to oscillate by means of an electrostatic drive. Three elements in each case form an oscillator structure. The oscillators are in each case suspended on opposite side edges by at least one web between an associated plate-like support and an associated drive plate element. The two supports and the two drive plate elements are, in each case, arranged one above the other in layers. A fixed plate element is located between the two drive plate elements so that, in each case, an identical narrow drive gap is defined between the drive plate elements. The drive gap is considerably smaller than the distance between the plate-like oscillators. An intermediate support that fills the intermediate space is inserted between the two plate-like supports and is completely electrically isolated from the surrounding frame to further reduce the respective capacitances to be recharged. The invention reduces the electrodynamic coupling between the drive and the read-out by a factor of about 100 in comparison with known micromechanical rotati…