Patent ID: 8306775

Claim:
An apparatus detecting information of a tire of a vehicle, including: a wheel sensor for detecting passage of teeth of a gear provided in association with tires of the respective wheels of a vehicle; a number-of-teeth calculation device calculating, based on time information as a time required for the teeth of the gear to pass obtained by the wheel sensor, the number of teeth of the gear passed per a sampling cycle set in advance; and a wheel speed calculation device regularly calculating rotation speed information of the tire with using the number of teeth calculated by the number-of-teeth calculation device, wherein the number-of-teeth calculation device uses, when an accumulated value of the time information at a sampling cycle exceeds the time at which the next sampling cycle is started, a ratio between time information at the point and a remaining time until the time at which the next sampling cycle is started is reached, thereby calculating the number of remaining teeth until the time at which the next sampling cycle is started is reached and calculating the number of teeth passed during the sampling cycle, and wherein the wheel speed calculation device calculates tire rotation speed information based on an interval between neighboring teeth in the gear, the number of teeth passed during the sampling cycle, the number of remaining teeth calculated by the number-of-teeth-calculation device, and the sampling cycle.