Camera diaphragm drive apparatus

US3940781A · kind A · utility

Assignee

• VEB Pentacon Dresden · DE

Inventors

• Wolfgang Krause · Waibstadt, DE
• Friedhelm Spanke · Canora, CA

Key dates

• Filing date: Dec 2, 1974
• Grant date: Feb 24, 1976
• Expiry date: Dec 2, 1994

Classification

• Technology area (CPC G): Physics
• CPC primary: G03B7/20
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A diaphragm drive apparatus for an objective lens with a manually preselectable diaphragm. The diaphragm drive apparatus is provided within the objective housing and is actuable by the shutter release mechanism of the camera to which it is affixed. The apparatus includes a plunger which operates a release mechanism. This release mechanism operates a drive lever which effects a connection with a diaphragm blade drive ring. A cam follower provided on an arm of the drive lever follows a cam surface on the release mechanism. The cam surface has one portion for effecting movement of the cam follower in engagement with the cam surface and a second portion which does not impart movement to the cam follower. On operation of the release plunger by the release system in the camera, the initial movement of the release mechanism on the drive lever effects closure of the diaphragm to its manually preselected position selected on the diaphragm setting ring and on subsequent movement permits release of the camera shutter mechanism without further movement of the diaphragm.