US PATENT SUBCLASS 251 / 189
.~.~ Piston with expansible packing


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

157  DF  WITH MEANS TO INCREASE HEAD AND SEAT CONTACT PRESSURE {8}
187  DF  .~ Separate actuators or actuator motion {2}
189.~.~ Piston with expansible packing


DEFINITION

Classification: 251/189

(under subclass 187) Subject matter comprising piston type valves provided with expansible packing.

SEE OR SEARCH CLASS

277, Seal for a Joint or Juncture, for a generic sealing means or process,

637+, for a static contact seal for other than an internal combustion engine, or a pipe, conduit, or cable having a particular associated mounting or retaining means.