04170245 is referenced by 25 patents and cites 12 patents.

A digital valve has a valve body with an inlet passage and two outlet passages straddling the inlet passage. A plurality of slots are cut in the body connecting the inlet passage to each outlet passage. Bores in the valve body intersect each slot, and a plunger in each bore blocks or opens the slot. The slots vary in width in a binary progression, and solenoids, controlled by a central processing unit through solid state relays, selectively actuate the plungers so that a desired flow through the valve can be effected. Upstream and downstream sensors are connected to the central processing unit, which is within the valve, to modify the actuation of the plungers in order to provide a predetermined flow at the instantaneous temperature of the fluid and the instantaneous pressure drop across the valve.

Title
Digital control valve
Application Number
5/883423
Publication Number
4170245
Application Date
March 3, 1978
Publication Date
October 9, 1979
Inventor
Frank P Haley
Upland
CA, US
Agent
W W Ritt Jr
J F Verhoeven
Assignee
FMC Corporation
CA, US
IPC
G05D 7/03
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