Patent CN2148941Y - Screw micrometer for teaching - Google ...

一种由螺杆、固定套筒、微分筒、弓架组成的螺旋测微器：固定套筒固定在弓架的一端；螺杆 ... A by-screw, fixed sleeve, differential cylinder, bow rack consisting of screw micrometer: fixed end ...

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