Adjustment of micrometer screw - utilises two screws with different steps for rapid and differential movement

摘要

Adjustment of micrometer screw for machine tool or measuring instrument comprises two screws with different steps. This provides rapid and differential movement of micrometer screw to improve precision. The micrometer comprises machine housing (1) with plates (2) which include bearings and axial shoulders for nut (6) and locking mechanism (8). One nut (5) acts with primary screw (3) to provide rapid movement while second screw (4) provides differential step in conjunction with its nut (6) which has a shoulder (7). A conical clutch (9) provides engagement between differential screw and its nut and is moved by knurled knob (14) to engage or disengage.