Knock sensor

US5398540A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Robert Entenmann · Memmingen, DE
• Joerg Bonitz · Rochlitz, DE
• Stefan Unland · Schwieberdingen, DE
• Romuald Fries · Rutesheim, DE
• Robert Sloboda · Yokohama, JP
• Klaus Schenk · Bietigheim-Bissingen, DE
• Karl Dums · Renningen, DE

Key dates

• Filing date: Jun 11, 1993
• Grant date: Mar 21, 1995
• Expiry date: Jun 11, 2013

Classification

• Technology area (CPC G): Physics
• CPC primary: G01L23/222
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A knock sensor for indirect or direct fixing to an internal combustion engine has a housing (10) with a pressure sleeve (11) on the outer side of which a piezoceramic disk, a seismic mass (16), the contact disks (14), and the insulating disks (13) are arranged. The insulating disks (13) or the piezoelectrical disk (15) are or is made slightly electrically conductive so that the voltage spikes which occur due to the pyroelectrical effect can be easily eliminated. In this way, faulty measuring and interference can be avoided in the electrical circuit connected to the knock sensor.