Fluid handling – Systems – Multi-way valve unit
Reexamination Certificate
2008-03-18
2008-03-18
Rivell, John (Department: 3753)
Fluid handling
Systems
Multi-way valve unit
C137S625690, C251S050000
Reexamination Certificate
active
07343934
ABSTRACT:
A proportional pressure control valve which includes an electric first stage pilot having a single outlet port configured to provide a variable pressurized hydraulic fluid to the outlet port and at a pressure that is proportional to an electric input signal and which is variable between first and second values and further includes a second stage hydraulic valve which has a spool reciprocally moveable in a bore between first and second positions indicative of a full ON and a full OFF condition. A fluid isolation chamber is oriented in the bore and in a region between a control port and a tank port in the fluid pathway therebetween. The interior wall of the bore and the first and second diameter regions on the spool are configured to always provide a controlled volume fluid flow rate between the control port and the fluid isolation chamber.
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Bowden Charles J.
Pride, II Steven R.
Fema Corporation of Michigan
Flynn ,Thiel, Boutell & Tanis, P.C.
Rivell John
LandOfFree
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