Edward Griffiths

43063144, Dec 15, 1981

Sep 2, 1980

6/183020

Edward E. Griffiths - San Jose CA

H04B 900

455603

Hydraulically operated equipment, e. g. , cranes or the like, may be accurately controlled by a remote control coupled by a fiber optic link to hydraulic valve control servo circuitry at the equipment site. Analog input voltage levels representing various functions and/or motor positions are pulse position modulated for transmission through the fiber optic link, and are reconverted into analog signals for controlling selected motors and valve actuating solenoids. Novel safety features are incorporated for stopping and delaying all control if a deadman switch is released or if a function is incorrectly selected, and a standby power pack automatically neutralizes all motors and functions in the event of failure of the main power source.

D2716879, Dec 6, 1983

Dec 5, 1979

6/100701

Edward E. Griffiths - San Jose CA

D1303

D13 32

42403049, Dec 23, 1980

Jun 30, 1978

5/920674

Edward E. Griffiths - San Jose CA

F16K 3105
G05G 900
G05G 1100
G05G 506

74471R

Valve operating system which is particularly suitable for use in the remote control of valves such as the function control valves of a crane or loading apparatus. The system includes output shafts for connection to the operating levers of the valves and input shafts disposed telescopically of the output shafts. A drive motor is connected to the input shafts for moving the same in unison along their axes, the detent means are provided for selectively locking the input and output shafts in each pair together. The detent means are operated by electrically energized solenoids which can be controlled remotely, e. g. from a hand held control unit connected to the remainder of the system by a cable.