| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a tire position determination system capable of accurately determining a tire position, with a simple structure without using an initiator (trigger).SOLUTION: When a peak of a gravity component is detected, each of tire air pressure detectors 4a-4d transmits peak information Spk to a receiver 12. Each time the receiver 12 receives the peak information Spk, the receiver stores, in memory 15, rotational frequency of an axle of a representative wheel at that time, and at a first determination timing after acquisition of rotational frequency of axles of four wheels is completed, calculates a detector angle at the first determination timing, on the basis of the rotational frequency of the axle of the representative wheel. The receiver 12 executes this also at a second determination timing. The receiver 12 calculates a detector rotational angle of each wheel on the basis of the detector angle at the first determination timing and the detector angle at the second determination timing, calculates an axle rotational angle of each wheel on the basis of rotational frequency of axles, of axle rotational frequency detection sensors 19a-19d, counted between the first determination timing and the second determination timing, and determines tire positions from these rotational angles.</p> |
