1. Field of the Invention
This invention relates to a photographic camera using a film magazine having a light-shielding door for opening and closing a film exit slit, and more particularly to an improvement in the mechanism for opening and closing the light-shielding door.
2. Description of the Prior Art
Recently there has been proposed a film magazine comprising a magazine body having film exit slit and a light-shielding door for opening and closing the film exit slit. Generally such a film magazine is provided with a film spool which is supported for rotation in the magazine body and around which a roll film is wound. When the light-shielding door is closed, the whole roll film is accommodated in the magazine body in a light-tight fashion and when the spool is rotated while the light-shielding door is opened, the film is wound into or off the magazine body.
In a photographic camera using such a film magazine, a mechanism for opening and closing the light-shielding door (simply referred to as "door opening mechanism herein) is required and the door opening mechanism must be actuated in response to closure of a light-shielding lid of the camera.
Though the door opening mechanism may be actuated by manually operating an actuator provided on the camera body, such an additional operation is inconvenient to the users who are accustomed to cameras using conventional film magazines without light-shielding door.
In U.S. Pat. No. 5,231,438, there is disclosed a camera in which the door opening mechanism is automatically actuated in response to closure of the light-shielding lid of the camera and no additional operation is required for actuating the door opening mechanism. In the camera, the door opening mechanism is interlocked with the light-shielding lid of the camera by way of a member urged by a spring in one direction and the user must move the member in the reverse direction overcoming the force of the spring when the light-shielding lid is closed. Accordingly, the camera is disadvantageous in that a large force is required when closing the light-shielding lid of the camera.
USPTO Backgrounds
USPTO Backgrounds