US PATENT SUBCLASS 219 / 644
.~.~.~ Interior surface


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

Internet Version by PATENTEC © 1999      Terms of Use



219 /   HD   ELECTRIC HEATING

600  DF  INDUCTIVE HEATING {7}
635  DF  .~ Specific heating application {8}
643  DF  .~.~ Tube (i.e., pipe) {1}
644.~.~.~ Interior surface


DEFINITION

Classification: 219/644

Interior surface:

(under subclass 643) Subject matter wherein the heating is applied to an inner tube wall.