Vehicle tire pressure supervisory system
US4064482A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1976 |
| Grant date | Dec 20, 1977 |
| Priority date | — |
| Expiry date | Oct 15, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60C23/0408
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The wheels at opposite ends of an axle - and which may be twin or tandem wheels -- each have a pressure switch and a tank circuit associated therewith, rotating with the wheel. The tank circuits includes a normally closed pressure-sensitive switch which, when the pressure in the respective tire drops below a certain value, opens the tank circuit. The coil of the tank circuit is coupled with a transducer coil connected to a blocking oscillator which, upon passage of the tank circuit, provides an output pulse. The frequency or recurrence rate of the output pulses from opposite ends of the wheels at an axle are compared in an integrating comparator and, if the frequencies differ after a predetermined integration time, provide an alarm signal. The integrator or a digital counter which should have a number of count stages, only the last one providing an alarm signal to allow for variation in frequency with normal tire pressure when the vehicle rounds a curve. Tandem or multiple wheels at one end of the axle each can be provided with a tank circuit, offset 90.degree. with respect to each other, however. Use of tandem wheels increases the absolute frequency and does not change the compari…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.