Patent · US Expired

Alarm device for informing reduction of pneumatic pressure of tire

US4180795A · kind A · utility

163Cited by
2References
5Claims
0Family size

Assignees

Inventors

Key dates

Filing dateDec 12, 1977
Grant dateDec 25, 1979
Priority date
Expiry dateDec 12, 1997

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60C23/0428
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

An alarm device for informing reduction of pneumatic pressure of vehicle tires by sensing abnormal change of tire internal pressure of a vehicle when running by a pressure sensing switch, by converting the thus sensed abnormal change into an electric signal and by generating an alarm to an operator. This device comprises an oscillator having an oscillation coil fixed on a chassis side of the vehicle; a resonator consisting of a resonance coil and a capacitor fixed to a peripheral portion of the rotating wheel having tire adjacent the oscillation coil and for resonating with an electromagnetic wave radiated from the oscillation coil; a signal processing device containing a sensing means for sensing change in an oscillation condition generated in the oscillator due to a resonant condition of the resonator switched on and off in accordance with abnormal internal pressure of a tire and for processing a signal sensed by this sensing means; and an alarm for generating a warning by the output of this signal processing device.

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