(under the class definition) Devices which have a plurality
of similar electrodes and which are provided with means other than the mere terminals of the electrodes so that one of the similar electrodes can be used to the exclusion of the other, the means being capable of selecting either of the similar electrodes for use.
(1) Note. Some of the devices in this subclass are designed so that one electrode may be used until the electrode fails to operate properly and then another electrode may be substituted for the electrode which failed.
(2) Note. This subclass does not include devices, which include no more structure than a device having the electrodes connected to separate terminals so that different electrodes may be selectively energized by connecting their respective terminals to proper sources of electrical current or potential without altering in any way the structure of the lamp or discharge device. For example, excluded is a multiple filament lamp which is provided with three or four terminals so that either filament may be energized by connecting the current supply conductors to the proper filament terminals. Also excluded is the control grid type discharge device which may be operated as a diode rectifier by either connecting the control grid to the anode or leaving the control grid unconnected. The devices in this subclass include some structure in the lamp or discharge device which is provided only to make it possible to selectively use the electrodes. For example, included in this subclass are two filament devices having three terminals for the filaments, one terminal being covered by insulation until one of the filaments fails when the insulation is removed and the other filament used. Also included are devices having two filaments with two terminals, one filament not being connected to a terminal, the device being provided with means for connecting the second filament to the terminals when the first filament fails.
SEE OR SEARCH THIS CLASS, SUBCLASS:
52, for devices under the class definition which are provided with means for converting the device into a different type of device, such as converting a three electrode discharge device so that it operates as a two electrode device.
121, for spark plugs having reversible parts so that a new part can be substituted for a worn part by reversing a part (e.g., as the core and center electrode). 128, for spark plugs having a plurality of center electrodes so that one may be used when the other is worn.
140, for spark plugs having a plurality of electrodes or an electrode with plural joints cooperating with another electrode so that as one electrode wears and the spark gap becomes too wide the spark will form between another electrode or electrode point (e.g., multigap spark plugs).
237, for devices under the class definition which are provided with means for replacing an electrode which is defective or which are provided with an envelope and parts that are made so that the device can be readily disassembled to repair a defective portion of the device.
306+, and the subclasses specified in the notes to the definition of those subclasses for discharge devices with three or more electrodes.
316, and the subclasses specified in the notes to the definition of those subclasses for lamps having a plurality of filaments or glowers.
SEE OR SEARCH CLASS
314, Electric Lamp and Discharge Devices: Consumable Electrodes,
1+, for discharge devices of the consumable electrode type (e.g., arc lamps and similar devices provided with means for feeding the electrodes together) which have means for substituting one electrode for another when the first electrode is consumed or fails to operate properly.
315, Electric Lamp and Discharge Devices: Systems,
32+, for electric lamps and discharge devices which have structurally combined therewith a circuit element, such as a switch or fuse, which circuit element may be for the purpose of permitting the selective use of the electrodes of the device, see especially indented subclass 65 for lamps and discharge devices which include a plurality of filaments, one of which is maintained in nonoperated condition while another is in operative condition and which have means for automatically substituting the nonoperating filament for the operating filament when either the operating filament fails or when the conditions of the supply circuit change so that it is desirable that the nonoperating filament be substituted for the operating filament. Subclasses 88+, for systems for supplying electrical energy to lamps and discharge devices which are provided with means for automatically substituting another electrode in the lamp or discharge device for an electrode which has failed or which is provided with means for substituting another lamp or discharge device for a lamp or discharge device which has failed.
