Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Telephone intercommunication system providing common access to a communication line










Image Number 4 for United States Patent #3931479.

A private telephone intercommunication system including facilities for connecting the system to a telephone central office. Common supervisory means are provided to control access to a line from each station.








 
 
  Recently Added Patents
Light emitting diode having multi-cell structure and method of manufacturing the same
Integrated circuit testing with power collapsed
Solution based precursors
Stool
Power generating apparatus of renewable energy type and method of attaching and detaching blade
Stock analysis method, computer program product, and computer-readable recording medium
Mobility management in a communications system
  Randomly Featured Patents
Aluminum furnace skim recovery system
Air-cushion backpack
Topical doxyl composition and method
Wellbore flow control devices comprising coupled flow regulating assemblies and methods for use thereof
Configurable arrhythmia analysis algorithm
Odor preventing hunting apparel
Model motorcycle
Self-formation of high-density defect-free and aligned nanostructures
Slide switch of anti-reverse mechanism for fishing reel
Storage structure for collapsible seat