DETECTION ELEMENT FOR OBJECTS AND DETECTION DEVICE USING THE SAME

摘要

A body detecting element (10) is buried in the ground together with a body (20) such as a metal body and includes a magnetic member (11) acting as a magnetic core, an antenna coil (12) wound around the magnetic member and a capacitor (13) connected to both the ends of the antenna coil for forming a resonance circuit together with the antenna coil (12). The antenna coil (12) is mounted on the body (20) integrally therewith through an electromagnetic shield member (14) with the outer peripheral surface thereof confronting the outer surface of the body (20). A body detecting element (60) includes an RFID circuit (63) connected to an antenna coil (62) and mounted on a body (70) integrally therewith such that the outer peripheral surface of the antenna coil (62) confronts the outer surface of the body (70) through an electromagnetic shield member (64). Even if the body detecting element is mounted on the body such as a metal pipe and the like integrally therewith, it can accurately detect the body because a resonant frequency and the Q value of the coil are not changed. There is almost no possibility that detecting element is broken or moved even if a body other than the above body is dug. <IMAGE>