Douglas J. Williams

Follow

Person

Valencia, CA, US

People

Patents Grantslast 30 patents

Information Patent Grant
Electronic parking meter and electric automobile recharging station
- Patent number 6,081,205
- Issue date Jun 27, 2000
- Douglas J. Williams
- B60 - VEHICLES IN GENERAL
Information Patent Grant
Rack and pinion valve operating system
- Patent number 5,588,403
- Issue date Dec 31, 1996
- Douglas J. Williams
- F01 - MACHINES OR ENGINES IN GENERAL ENGINE PLANTS IN GENERAL STEAM ENGINES
Information Patent Grant
Automatic signaling device
- Patent number 4,252,076
- Issue date Feb 24, 1981
- Douglas J. Williams
- G10 - MUSICAL INSTRUMENTS ACOUSTICS
Information Patent Grant
Solar panel
- Patent number 4,244,354
- Issue date Jan 13, 1981
- Douglas J. Williams
- F24 - HEATING RANGES VENTILATING
Information Patent Grant
Low pressure differential detecting whistle
- Patent number 4,215,646
- Issue date Aug 5, 1980
- Douglas J. Williams
- G01 - MEASURING TESTING
Information Patent Grant
Fluid filter and purifying apparatus
- Patent number 4,016,080
- Issue date Apr 5, 1977
- Douglas J. Williams
- C02 - TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE