US PATENT SUBCLASS 251 / 51
.~.~.~ With choke by-pass or relief means

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

Internet Version by PATENTEC © 1999      Terms of Use


251 /   HD   VALVES AND VALVE ACTUATION

12  DF  FLUID ACTUATED OR RETARDED {12}
48  DF  .~ Dashpot or fluid controlled retarder or timer {5}
50  DF  .~.~ Line pressure connected dashpot or choke chamber {2}
51.~.~.~ With choke by-pass or relief means

DEFINITION

Classification: 251/51

(under subclass 50) Subject matter in which means are provided to shunt fluid around or enlarge the restricted communication.

(1) Note. Usually the shunt path is provided to permit unretarded motion of the valve in either its opening or closing movement while retarding the other movement.

(2) Note. Frequently the shunt path is controlled by either a check valve or a cup type of packing on the piston of the expansible chamber to produce a one-way retarding action on the valve.

SEE OR SEARCH THIS CLASS, SUBCLASS:

35, for choked pressure type servo-motor actuators for valves in which the choke passage varies according to the valve position.

55, for dashpots which are not line pressure connected, but which have choke by-pass or relief means.