Linear-angular measuring instrument for human bone deformities - has goniometer connected by telescopic rod to measuring tape housed within box contg. openings for spirit levels

摘要

The measuring instrument has a goniometer (10) mounted in a case (11), a box (12) containing an automatic rewind measuring tape (13) wound on a core (25), and a cylindrical telescopic rod (14) which connects the case to the box. The case has a rotating circular stud (15) on one face surrounded by an annular graduation (16). The stud also carries an axially sliding graduated rule (17) lodged in a diametral slot. The box is in two moulded parts assembled by means of a screw (18) and has a window (19) for reading the graduations on the measuring tape. It also has two rectangular openings (20,21) which contain spirit-levels (22,23) to assist in horizontal and vertical settings. The free end of the measuring tape is retained by a flange (26) terminated by a loop (27) and mounted so that it may turn freely around its axis in a plug (28). In this way the tape remains constantly flat and is not subjected to any torsion. The instrument is particularly suitable for bone deformation measurements on the human body.