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
Method and apparatus for generating images using a color field sequential display
Braided boomerang pet toy
Quantitative sleep analysis system and method
Dispensing of restricted goods
Shape memory polymers formed by self-crosslinking of copolymers
Defected ground plane inductor
Control of an electric machine
  Randomly Featured Patents
ICA angioplasty with cerebral protection
Vehicle wheels
Jet printing inks containing polymerized fatty acid-based polyamides
Electronic toy house
Atomizer and uses thereof
Resilient paint can accessory
Lens control apparatus, image pickup apparatus, and lens control method
Safety device in lighting rods
Renin inhibitors
Developing agent for silver halide photographic material, developing solution composition and method for developing silver halide photographic material