.~ With heater-unit housing, casing, or support means (e.g., frame and single sheet) {13}
532
.~.~ With open frame or grid-type support
DEFINITION
Classification: 219/532
(under subclass 520) Subject matter wherein the significant support means is comprised of an open frame or grid with the heating unit or units supported on or by the grid members usually by tubular or spool type insulator means. The
heating element or elements in this subclass are generally exposed straight resistance wire or coils but they may be sheathed, as in a "Calrod" type.
SEE OR SEARCH CLASS
338, Electrical Resistors, appropriate subclasses for open frame or grid supported resistance elements, particularly
226+, for incased resistors, which may be comprised of zigzag or helical wound type, subclasses 283+ for zigzag or sinuous type, subclasses 296+ for helical or wound type elements in general and subclasses 315+ for resistors, per se, combined with mounting or supporting means.
