| 摘要 |
<p>The present invention offers a pressure monitor and a method of controlling the pressure monitor for a vehicle tire which enable reducing electric power consumption and issuing an alarm, when the tire pressure is equal to or lower than a predetermined alarm tire pressure. The pressure monitor comprises a signal sending device (10) and a signal receiving device (12). The signal sending device (10) includes a tire pressure sensor (16) and a battery (14). The tire pressure sensor (16) detects a tire pressure at each interval time, a predetermined unit time delta t. The signal sending device (10) sends an electric signal to the signal receiving device. The signal receiving device (16) receives the electric signal from the signal sending device (10) and issues an alarm when the detected tire pressure is equal to or lower than a predetermined tire pressure P1, P2 and P3 (P1 > P2 > P3). The signal sending device (10) is installed on a wheel and is driven by the battery (14). The signal sending device (10) sends the electric signal of the tire pressure detected by the tire pressure sensor (16) at periodical interval DELTA T and sends at the time when a change in the value of the detected tire pressure in the interval n2 x delta t is equal to or more than the value of n2 x delta pt. The number n2 is set to satisfy with 0 < n2 ≤ n1 (n1 = DELTA T / delta t). The predetermined standard value delta pt is, for example, set to satisfy an equation delta pt = (a normal tire pressure-the first alarm tire pressure)/n1. <IMAGE></p> |
