Patent ID: 6664890
Filing Date: 2003-12-16
Classification: B60C

Abstract:
An air pressure detection device for a tire comprising:an air pressure sensor for measuring the air pressure of a said tire; a temperature sensor for measuring the temperature at a predetermined portion in said tire; a reduced air pressure arithmetic means for calculating a reduced air pressure Pm from the air pressure measured by said air pressure sensor and the temperature measured by said temperature sensor, the reduced air pressure Pm being calculated by the following formula: Pm=Pxâˆ’K(Txâˆ’T0) where Px is the air pressure of said tire measured by said air pressure sensor, Tx is a temperature at said predetermined portion in said tire measured by said temperature sensor, T0 is a recommended temperature corresponding to a recommended air pressure of said tire, and K is a predetermined constant; and an alarm signal generating means for generating an alarm signal when the reduced air pressure calculated by said reduced air pressure arithmetic means is lowered to or below a predetermined first threshold value.