| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a tire pressure drop detecting device for determining pressure drop based on a single determination threshold value. <P>SOLUTION: There are provided a rotation information detecting means for periodically detecting rotation information of each wheel of a four-wheel vehicle, a wheel speed calculating means which calculates the wheel speed of a tire from the rotation information, a comparison value calculating means which calculates a difference between the sum of speeds of two wheels at one diagonal positions and the sum of the other as a first comparison value while calculating a difference between the sum of the speeds of two wheels on one side positions and the sum of the others as a second comparison value, a determination means for determining pressure drop of a tire based on the relationship between a predetermined determination threshold value and the first and second comparison values, and an alert means which issues an alert if the determination means determines that the tire pressure has dropped. A conversion means is further provided in which the amount of change of the first and second comparison values caused by pressure drop from a normal value having been learned during normal pressure is unified between front wheel and rear wheel, and the determination means determines pressure drop based on a single threshold value. <P>COPYRIGHT: (C)2012,JPO&INPIT |
