PURPOSE: To perform high-precision detection by providing a fixed part, the 1st movable member supported with the 1st parallel springs fixed at one terminal on the fixed part, and the 1st electric contact between the fixed part and the 1st movable member.

CONSTITUTION: A contact detector has the fixed part 1, which forms the external cylinder of the contact detector. Then, the 1st movable member 2 is supported on the fixed part 1 with the 1st parallel springs 3 and 4. Further, the 2nd movable members 5 are supported with the 2nd parallel springs 6 and 7 provided to said 1st movable member 2 in parallel to the 1st parallel springs 3 and 4. This 2nd movable member 5 holds the contactor 9 having a contacting ball 8 atop. Thus, the high-precision contact detection is performed.