Pressure monitor
AssigneeGrathnail Development Company Limited
InventorsGuy L. B. Smith, Derik Howard, Anton B. Goedhals
Life of this patent
Estimating the term…
Abstract
A tire pressure monitor which includes a signal generating section and a signal processing section. The signal generating section has a transducer which produces a first signal which is dependent on the tire pressure, and a transistor the collector current of which is controlled by the first signal. The signal generating section is supplied with power from a battery source and the current so supplied includes the collector current and is therefore dependent on the tire pressure. The signal processing section includes a monitor which monitors the supply current to the signal generating section and a display for providing an indication of the tire pressure.
Claims6
An apparatus for continuously providing a measurement of pressure in a tire of a vehicle, comprising:
- signal generating means;
- signal processing means;
- current supply means connected to said signal generating means and to said signal processing means;
- said current supply means supplying a first electrical current to said signal generating means and a second electrical current to said signal processing means, said current supply means having a circuit connection so that said first and second electrical currents are always in a substantially fixed ratio to each other;
- said signal generating means including transducer means for generating a first signal which is dependent on the pressure inside the tire;
- and a control means connected to said transducer means and to said current supply means, said control means being responsive to the first signal for varying said first electrical current in dependence on said tire pressure;
- said signal processing means monitoring said second electrical current thereby to provide a continuous indication of said tire pressure.
Dependencies are inferred from the claim text.