Patent ID: 7802374

Claim:
A capacitive digital caliper used for measuring inside or outside dimensions of the measured object comprising a main beam with jaws on its end portion; and a slider sliding along the length of said main beam, having jaws on its end portion matching with those of said main beam, provided with a measuring display device comprising a measuring display and a measuring circuit board, wherein, a rack is provided along the length of said main beam, and is suitable for the range of said main beam; said slider is provided with a gear system comprising at least a pinion and its shaft, engaged with said rack; and a sealed cavity is provided with a stator plate of a first electrode forming a certain pattern fastened on said slider and electrically coupled with said measuring circuit; and a rotor plate of a second electrode forming a certain pattern concentrically opposed at a distance to said first electrode set, and fastened onto said shaft of said gear system, which penetrates through a motive sealing member on said cavity wall, and connected to said gear system outside said cavity.