Patent Leaderboard
USPTO Patent Rankings Data through Dec 31, 2025
Home › Communication system with voice announcement means

Communication system with voice announcement means

US Patent 4720848 · Granted Jan 19, 1988

Assignee

Inventors

View full patent text on Google Patents →

More Patents by These Inventors

Personal-servicing communication system1996
Personal-servicing communication system1995
Personal-servicing communication system1992
Personal-servicing communication system1990
Personal-servicing communication system1988
Communication system with operation-procedure guiding function by speech1988
Personal-signaling communication system1987