(under the class definition) Devices which are convertible from one type of device to another type of device.
(1) Note. Many discharge devices may be considered to be convertible from one type of discharge device to another type of discharge device simply by not using some of the electrodes of the discharge device. For example the usual triode may be used as a half-way rectifier by not connecting the grid in any circuit. In the device in this subclass some means must be provided which is limited to use in converting the device from one type of device to another type of device. An example of the subject matter in this subclass is an incandescent lamp which has the lead wires coated with electron emissive material so that when the filament fails a glow discharge may take place between the coated lead wires thus converting the incandescent lamp to a discharge device type lamp. Note that where the converting means is an electric switch or other circuit element such as an impedance, the device is excluded from this class and will be found in Class 315, subclasses 32+. Also excluded from this subclass are incandescent lamps having plural filaments, such as a high resistance filament and a low resistance filament, which may be converted from one type of incandescent lamp to another merely by connecting one filament or the other in the circuit.
(2) Note. See the class definition for the classification of lightning arresters of the arc or spark type which are designed to have the electrodes brought into contact with each other upon prolonged use of the device thereby
establishing a conductive path through the device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
1+, for plural unit devices under the class definition, that is, devices which include in structural combination a plurality of discharge devices, a plurality of lamps other than mere multiple filament lamps, or a lamp and discharge device.
236, for devices under the class definition which are provided with a spare or extra electrode which is not used until one of the electrodes fails to operate properly when the spare or extra electrode is used to replace the defective electrode. SEE OR SEARCH CLASS
315, Electric Lamp and Discharge Devices: Systems, see (1) Note above.
