| 摘要 |
PROBLEM TO BE SOLVED: To provide a transmission device that is connected to a tire cavity via a housing having a through hole that is hardly occluded with a puncture repair solution, and a tire information monitoring system employing the transmission device.SOLUTION: A transmission device 100 includes a sensor 110 that detects as tire information a state of an air with which a tire cavity enclosed with a tire and rim is filled, a transmitter 112 that wirelessly transmits the detected tire information, and a housing 102 in which the sensor and transmitter are stored. The housing has a through hole 122 that penetrates through a wall of the housing and extends in a direction orthogonal to a sensor detection surface 111. The area of an external opening 122a of the through hole is equal to or smaller than 0.8 mm, and the sensor detection surface faces an internal opening 122b on an internal side of the housing of the through hole without intervention of a space. A distance that is the length of the through hole ranges from 3 to 15 mm, and a ratio A/V of an area Ammof a side wall of the through hole to the volume Vmmof the through hole ranges from 3.0 to 30.0 mm. |
