Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Photographic camera










Image Number 3 for United States Patent #4440481.

A photographic camera of a type utilizing a roll of film comprises a camera back lid, a take-up spool for taking up the film therearound, and a plurality of switches incorporated in the take-up spool. The switches built in the take-up spool are all closed, when the film is turned around the spool, to generate a signal inidcative of the fact that the film has no doubt been secured to the spool. An electric circuit is also provided for disabling the film wind-up so long as the camera back lid has not yet been closed even though the film has already loaded in the camera.








 
 
  Recently Added Patents
Area efficient through-hole connections
Asynchronous task execution
Method of hydrothermal liquid phase sintering of ceramic materials and products derived therefrom
Air driven alternators for battery powered vehicles
Method and system for providing cloud based network security services
Managing breakpoints in a multi-threaded environment
Method, apparatus, and system for energy efficiency and energy conservation including dynamic cache sizing and cache operating voltage management for optimal power performance
  Randomly Featured Patents
Apparatus for the preparation of hollow plastic articles
Missile jet vane control system and method
Gravel pack apparatus and method
Optimized control of an energy supplying system and an energy consuming system
Potassium-lithium-niobate crystals and the manufacture thereof
Method for inhibiting pathogenic fungi and bacteria in plants using Pseudomonas aureofaciens
Method and apparatus for use in a network of the ethernet type, to improve fairness by controlling the interpacket gap in the event of channel capture
Apparatus and methods for bone, tissue and duct dilatation
Compositions and methods for creating electronic circuitry
Endothelium preserving microwave treatment for atherosclerois