Abstract: The invented probe device comprises a base and a probe. The probe comprises a cap and an elastic member. The elastic member provides a force to push the cap ourwardly. The cap has a cylinder and a substantially slope peripheral at the top of the cylinder. The probe may further comprise a support, slidably connected with the cap. In the lower part of the support a notch is formed and screw threads are form at the side faces except at the surface of the notch. A fixing hole is provided in the base. The fixing hole has a recession so that the shape of the hole matches with the cross-sectional contour of the lower part of the support. A nut secures the lower part of the support tightly to the base.