Patent ID: 6137400
Filing Date: 2000-10-24
Classification: B60C

Abstract:
An apparatus for detecting a decrease in tire air-pressure in which decrease in internal pressure of tires is detected based on rotational information obtained from tires attached to a four-wheeled vehicle, the apparatus comprising:a rotational information detecting means for detecting rotational information of each tire;a memory means for storing reference values of rotational information of each tire;a calculating means for calculating a reciprocal of the turning radius of the vehicle for each tire based on the rotational information detected by the detecting means and the reference values of rotational information of each tire; anda determining means for determining a decrease in internal pressure of each tire at each turning radius of the vehicle from a relationship between each reciprocal of the turning radius of the vehicle for each tire, the detected rotational information and the reference values of rotational information of each tire.