| 摘要 |
The sensor unit is operated based on a first timing signal with a first interval. If there is no second timing signal with a second interval longer than the first interval, a tire internal-pressure information signal is transmitted when the alarm device judges a moving of a vehicle based on a signal from the tire rotational-movement detecting means, the signal having the tire internal-pressure data with a start bit, and the transmission of the tire internal-pressure information signal is stopped when the device judges a non-moving of said vehicle. If there is the second timing signal, the tire internal-pressure information signal is transmitted when the device judges the moving of the vehicle and N pieces of tire internal-pressure information signals are transmitted at third intervals (N is a natural number not less than 2) when the device judges a non-moving of the vehicle, each tire internal-pressure information signal having the tire internal-pressure data with said start bit. When a main switch of the vehicle is on, the receiving-side module is always in an operating state. When the main switch is off, the receiving-side module is intermittently operated at fourth intervals, each forth interval is shorter than (N- 1 ) times of the third interval, such that a second duration for operation of the receiving-side module is longer than the third interval.
|
