Helicoid member for lens in optical apparatus

Abstract

Abstract PURPOSE: To provide a good and inexpensive helicoid by manufacturing a helicoid member for lens by a plastic member and changing screw threads by providing the portions absorbing dimensional errors to the effective screwing portions of the helicoid. CONSTITUTION: A helicoid is so constituted by minutely changing part (a) of its pitch that the space of the part (a) differs from that of the other portions. It is equally well to let the leas angle of the part (b) differ from that of the other portions by minutely changing part of the lead angle of the helicoid. It is also equally well to change the shape of the screw thread of the part (c) by letting the shape of the screw thread of the helicoid differ partly from that of the other portions. All these constitutions not only prevent the helicoid from clattering but also prevent the formation of any oil wells in the helicoid and the unsmooth operation owing to oil starving of the helicoid. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Akiyasu Washimi

Bibliographic Details