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
Host route convergence based on sequence values
Signal processing and tiered signal encoding
Light-emitting device package structure
Device and method including a soldering process
Satellite mounting pole
Gemstone
Method and apparatus for allocating and obtaining IP address
  Randomly Featured Patents
Router and method for use in a communication system
Image reading apparatus, image forming apparatus and computer readable information recording medium
Post etching treatment process for high density oxide etcher
Golf practice aid system
Rotating orthodontic bracket with locking mechanism
Electrophotographic photoconductor and electrophotographic apparatus
Dial and movement fixing structure
Optical module and manufacturing method thereof
Ceiling attachment for full-height panel
Method and apparatus for detecting axial cracks in rotors for rotating machinery