Pentax have patented a vacuum back that's apparently for the 645 system (much needed if you ask me). In the usual fashion, it probably never see the light of day :-(
A film support and feed system of a camera includes a pressure plate, a film feed mechanism which moves the film frame in a space in front of the pressure plate, a film suction mechanism which brings the film frame into intimate contact with the pressure plate by vacuum aspiration, a reversible motor, and an associating mechanism which selectively associates the reversible motor with either the film feed mechanism or the film suction mechanism in accordance with a direction of rotation of the reversible motor. The reversible motor is associated with the film feed mechanism by the associating mechanism to operate the film feed mechanism when the reversible motor is driven to rotate in a forward direction, or to operate the film suction mechanism when the reversible motor is driven to rotate in a reverse direction. P�l - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
