DK

Dick J. Kolkman

AS American Standard: 2 patents #187 of 558Top 35%
US Union Switch & Signal: 1 patents #25 of 78Top 35%
📍 Gibsonia, PA: #142 of 383 inventorsTop 40%
🗺 Pennsylvania: #23,606 of 74,527 inventorsTop 35%
Overall (All Time): #1,627,658 of 4,157,543Top 40%
3
Patents All Time

Issued Patents All Time

Showing 1–3 of 3 patents

Patent #TitleCo-InventorsDate
6052050 Two-wire signal transmitter and method for maintaining integrity of electrical contacts Michael Edward Colbaugh, Benjamin A. Giovannelli 2000-04-18
4652986 Vital inverter driver 1987-03-24
4645148 Fail-safe voltage-limiting circuit for an audio frequency overlay track circuit 1987-02-24