US Patent 7293455 Sensor device for tire having displaceable antenna

A sensor device for a tire, having enhanced transmission capability without disturbing the assembly of a rim to the tire. With itself installed in the tire, the sensor device detects information inside the tire and transmits the result to the outside. The sensor device has a case for receiving an electronic component and an antenna electrically connected to the electronic component and extended to the outside of the case. The fore-end portion of the antenna is made to be displaceable outwardly in the tire radial direction by centrifugal force generated in the rotation of the tire.