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 system for physical verification using network segment current
Method and systems for detecting duplicate travel path
Memory device and self interleaving method thereof
Output queued switch with a parallel shared memory, and method of operating same
Methods for predicting cardiac toxicity
Accessory system for vehicle
Method for controlling a motor
  Randomly Featured Patents
Centrifuge
Holder, rack and support
Ballpoint pen
Signal processing system for construction machine
Agent for capturing substance having anionic substituent
Digital signature method and key agreement method
Mechanical non-serrated knife grinder and honer
Process for composite free layer in CPP GMR or TMR device
Magneto-optical recording medium
Stoma plug