US PATENT SUBCLASS 277 / 440
.~.~ Piston ring surface of dissimilar material or hardness

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

Internet Version by PATENTEC © 1999      Terms of Use


277 /   HD   SEAL FOR A JOINT OR JUNCTURE

345  DF  SEAL BETWEEN RELATIVELY MOVABLE PARTS (I.E., DYNAMIC SEAL) {10}
434  DF  .~ Piston ring or piston ring expander or seat therefor {15}
440.~.~ Piston ring surface of dissimilar material or hardness {2}
441  DF  .~.~.~> Insert
442  DF  .~.~.~> Surface coating, plating, or impregnation {2}

DEFINITION

Classification: 277/440

Piston ring surface of dissimilar material or hardness:

(under subclass 434) Piston ring including a surface of different material, hardness, or density from the rest of the piston ring.

SEE OR SEARCH THIS CLASS, SUBCLASS:

569, for a dynamic, circumferential contact seal for other than a piston having a peripheral radially sealing flexible extending portion (e.g., lip seal, etc.) including a lining or insert.

935+, for a seal for other than a piston ring surface made out of a particular material.