US PATENT SUBCLASS 137 / 490
.~.~.~.~ Pilot valve within main valve head

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


137 /   HD   FLUID HANDLING

455  DF  LINE CONDITION CHANGE RESPONSIVE VALVES {11}
485  DF  .~ Pilot or servo controlled {3}
488  DF  .~.~ Fluid pressure type {2}
489  DF  .~.~.~ Choked or throttled pressure type {4}
490.~.~.~.~ Pilot valve within main valve head

DEFINITION

Classification: 137/490

(under subclass 489) Apparatus in which the valve controlling the servo fluid pressure is physically located within the main or flow controlling valve.

SEE OR SEARCH CLASS

251, Valves and Valve Actuation,

38, for this subject matter wherein the valve actuation is not responsive to line condition.