Patent · US Expired

Impact sensor

US5028750A · kind A · utility

9Cited by

3References

6Claims

0Family size

Assignee

Messerschmitt Bolkow Blohm GmbH · DE

Inventors

Hans Spies · Brackenheim, DE
Alfons Woehrl · Schrobenhausen, DE
Horst Laucht · Bruckmühl, DE

Key dates

Filing date	Oct 23, 1989
Grant date	Jul 2, 1991
Priority date	—
Expiry date	Oct 23, 2009

Classification

Technology area (CPC H)Electricity
CPC primaryH01H35/145
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

A magnetic impact sensor for motor vehicles with a safety system such as an airbag or belt tensioner for an occupant restraint system, has a circuit breaker arranged in an electrical trigger circuit of the safety system for inflating the airbag or tightening the belt by closing the trigger circuit in response to an acceleration or deceleration effective beyond a prescribed time duration. For this purpose a magnet in combination with specially shaped pole pieces forms two magnetic circuits the magnetic conductances of which are influenced by the position of a ferromagnetic ball that moves in response to an impact relative to the pole pieces to thereby open or close the circuit breaker. Normally, in the absence of an impact the ball is in a first position that keeps the circuit breaker open. When an impact occurs the ball moves into a second position to close the circuit breaker and thus the trigger circuit.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.