Inventor

KOLKMAN DICK J

US5 patents

⚠️ This page may combine multiple inventors who share the name “KOLKMAN DICK J”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.

AMERICAN STANDARD INC

2 patents

US4645148AFeb 24, 1987

Fail-safe voltage-limiting circuit for an audio frequency overlay track circuit

AMERICAN STANDARD INC23 citations78

US4652986AMar 24, 1987

Vital inverter driver

AMERICAN STANDARD INC6 citations59

WESTINGHOUSE AIR BRAKE CO

2 patents

US4059845ANov 22, 1977

Fail-safe time delay circuit

WESTINGHOUSE AIR BRAKE CO9 citations70

US4099692AJul 11, 1978

Transfer apparatus for energy sources

WESTINGHOUSE AIR BRAKE CO6 citations59

UNION SWITCH & SIGNAL INC

1 patent

US6052050AApr 18, 2000

Two-wire signal transmitter and method for maintaining integrity of electrical contacts

UNION SWITCH & SIGNAL INC3 citations60