Patent · US Expired

Driving mechanism for a photographic lens

US5815744A · kind A · utility

5Cited by
5References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 15, 1997
Grant dateSep 29, 1998
Priority date
Expiry dateJan 15, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/08
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A driving mechanism is described for a variable-focus photographic lens adapted to move back and forth. The driving mechanism includes a first driving lens barrel movably received within a stationary lens barrel without rotating the first driving lens barrel around an optical axis with a driving force transmitted from an electric motor. The driving mechanism of the present invention provides a so-called three-state extension lens barrel which advantageously eliminates the necessity for incorporation of driving ring members into the stationary lens barrel and/or the first driving lens barrel, as well as the necessity for constructing the stationary lens barrel and/or the first driving lens barrel in multiple structure. Such an arrangement positively contributes to the realization of a thin and compact camera. A portion of the first driving lens barrel is formed with a support block which is, in turn, formed with a guide hole into which a guide rod extending in parallel to the optical axis is loosely inserted. A portion of the support block is formed with a nut holder into which a nut member formed therearound with a female screw is loosely inserted and then a driving screw extending…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.