US PATENT SUBCLASS 313 / 272
.~.~ Plural filaments


Current as of: June, 1999
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313 /   HD   ELECTRIC LAMP AND DISCHARGE DEVICES

238  DF  WITH SUPPORT AND/OR SPACING STRUCTURE FOR ELECTRODE AND/OR SHIELD {9}
271  DF  .~ For filament {6}
272.~.~ Plural filaments


DEFINITION

Classification: 313/272

(under subclass 271) Devices having supporting and/or spacing structure for a plurality of filaments at least two of which are separately energizable.

(1) Note. Where the device has a plurality of filaments all of which are connected to the same lead-in wires so that all of the filaments must be energized together, the structure is considered to be supporting and/or spacing structure for a plural section filament and classified in subclass 273.

SEE OR SEARCH THIS CLASS, SUBCLASS:

245, for discharge devices under subclass 238 which have means for supporting and/or spacing a plurality of electrodes which form a plurality of separate discharge spaces, at least two of which are emissive filaments.

273, see (1) Notes, above.

306, and the subclasses specified in the notes to the definition of that subclass for discharge devices under the class definition which have a plurality of emissive filaments and which do not include any significant supporting and/or spacing structure for the electrodes.

316, for incandescent lamps which have a plurality of separately energized filaments which do not involve any significant supporting and/or spacing structure for the filaments.