Being the device which detects the air pressure drops of the tire air pressure drops detection device and the tire which is installed

摘要

PROBLEM TO BE SOLVED: To provide an apparatus for detecting a decreased air pressure of a tire capable of detecting that an air pressure of a one-wheel tire completely reaches zero with high accuracy.;SOLUTION: This apparatus includes an acceleration dispersion calculation means for calculating dispersion, based on rotation speed information of tires of respective wheels of a vehicle and acceleration of tires calcurated by an acceleration calcuration means; a comparison means for comparing the calcurated acceleration dispersion of the respective tires; an estimation means for estimating, when a comparison result of the comparison means shows that the acceleration dispersion of a certain tire is greater than acceleration dispersions of the other tires, a decrease in air pressure of the certain tire; a test means for determining a tire having a rotation speed that is slower than a predetermined reference speed based on the rotation speed information of the tires of the respective wheels; and a determination means for determining, when a certain tire identified by the estimation means is identical with the tire identified by the test means, a decrease in air pressure of the certain tire.;COPYRIGHT: (C)2010,JPO&INPIT