Contour measuring instrument

The utility model relates to the technical field of measurement, in particular to a profile measuring instrument which comprises a rack, a longitudinal driving mechanism, a carrier, a transverse driving mechanism, a lifting driving mechanism and a measuring mechanism, the rack comprises a bottom frame and a cross beam, the cross beam is arranged on the bottom frame, the longitudinal driving mechanism is installed on the rack, and the lifting driving mechanism is installed on the carrier. The carrier is connected with the longitudinal driving mechanism, the transverse driving mechanism is installed on the cross beam, the lifting driving mechanism is connected with the transverse driving mechanism, the measuring mechanism comprises a switching assembly, a measuring head, a camera and a positioning camera, the switching assembly is connected with the lifting driving mechanism, and the measuring head, the camera and the positioning camera are all installed on the switching assembly. According to the profile measu