Patent Leaderboard
USPTO Patent Rankings Data through Dec 31, 2025
Home › Key telephone system with means for operatively connecting another key telephone systems

Key telephone system with means for operatively connecting another key telephone systems

US Patent 4641337 · Granted Feb 3, 1987

Assignee

Inventors

View full patent text on Google Patents →

More Patents by These Inventors

Multi-beam feeding apparatus1999
Global subscriber group service system1995
Expansible antenna apparatus1994
Physiologically active agent for agriculture use1990
Key telephone system1990
Key telephone system1990
1-[2-(4-Hydroxybenzoyl)ethanoyl]-2-piperidone and a process for production as we1990
Powdery compound emulisifier and its production1989
Data transmission system between a main CPU board having a wait signal generatin1989
Data transmission system between a main CPU board having a wait signal generatin1989
Heat transfer promoters and method of using the same1989
Ringing signal sending-out circuit1988