US2446157A - Electrode - Google Patents

Description

July 27, 1948. E. F. LOWRY ET AL 2,446,157

ELECTRODE Filed May 23, 1946 mrmiiz 3311mm Arnold itqflmcnck imam flu Zfqslmn INVENTORS' ATTORN EY Patented July 27, 1948 UNITED STATES PATENT. OFFICE mac'mona Erwin r. Lowry. Lynn, Arnold 1.. re ime. Dan- .vers, and William E. Leyshon, Salem, Mass, asfl ora to Sylvania Electric .Products Inc" Salem. Mala, a corporation of Massachusetts Application May 23, 1946, Serial No. 671,688

reclaims. 1

This invention relates to electric gaseous discharge devices and more particularly to those of the negative glowtype.

An o ject of this invention is to'provide an electrode for a negative glow discharge lamp.

Another-object of this invention is -to provide an electrode which will permit'maximum lightoutput.

. A further object is .to provide an electrode which will permit the lamp to be started at relatively low voltages.-

Another'object is to provide an electrode which is especially adapted for use in a glass envelope or other suitable container which is relatively small-in size.

Another object is to provide an electrode which possible the complete and substantially uniform illumination of the entire surface of the envelope in which the electrode is sealed.

Further objects, advantages and features will be. apparent from the following specification when read in conjunction with the accompanying drawing in which:

Figure 1 shows a lamp provided with the electrode assembly of our invention.

is so constructed geometrically that it makes stantially. frusto-conical in contour and the projected apex of the cone falls within the bulb.

no part of the bulb wall is hidden from the radiation originating at the surface of the electrode assembly.

Our invention is further characterized by a novel positioning of this electrode structure with reference to the stem'on which it is mounted. We have found that when this particular type of electrode structure is employed it permits the lower portion of the frusto-conical electrode structure to be fitted over the upper portion of the stem. This is a feature which is particularly bulb wall than others, thus causing a more con- Figure 2 is a front elevational view of a lamp mount with the electrode assembly of our invention mounted thereon.

Figure 3 is-a partial sectional view taken along v the longitudinal axis of the mount of Figure 2.

Our invention embodies the idea of providing a glow lamp with a new and novel electrode structure and assembly which comprises two identical stamped metal members which serve as the electrodes and which, when disposed on a suitable stem, present a substantially frustoconical "structure with the longitudinal peripheral edges of the two members adjacent each other and spaced a short distance apart, and the The outer centrated radiation at these points. These concentrated points of radiation are not present in our structure.

Another advantage which is "obtained by the frustoconical electrode structure of our invention is that it makes it considerably easier to apply a uniform coating of electron-emissive material thereto because the surface thereof is substantially a surface of revolution. is an added factor which contributes to the attainment of a light source which gives uniform light distribution.

The above-described structural features makes "practical the use of a stem with a long throat.

This in turn permits the disposition of a ballastfun'ctions alternately as the cathode and then the anode. Since the electrode assembly is subing resistor within the-throat as an integral part of one of the lead wires; This is a distinct advantage over conventional structures which usually incorporate the resistor in the lamp base.

Referring now to the drawing, the electrode assembly I, comprising electrode members 2 and 3, are supported by the wires 4' and 5 which are sealed in the press 6 of a stem I. The stem 1 is and 3 of the electrode assembly I. The elongated throat 8 of the stem 1 provides a suitable chamber for a ballasting resistor 13 which forms a part of one of the lead wires. The stem press 6 is provided with an aperture l4 and a tubulatlon l through which a connection may be made to any suitable system adapted to evacuate the bulb Hljafter the stem 1 has been scaled thereto.

The electrode members 2 and 3, when mounted on the wires 4 and 5, present a substantially frusto-conical structure with the longitudinal peripheral edges 1'6 adjacent each other and spacedpermits the illumination of the entire bulb surface with no part of the bulb wall hidden from radiation originating at the surface of the electrode assembly, without using a continuous electrode surface such as is produced by expensive deep-drawing operations. The conical design also allows the electrode assembly to be fitted around the top portion of the/stem, thus economizing on a short distance apart. Each electrode member 2 and 3 is provided with a. channel i8 which defines wings 25 extending longitudinally thereof, in which the upper portions of the wires 4 and 5 are seated. The wings 25 are crimped and the wires 4 and 5 are spot welded to the crimped wings at 26. The seating of a large portion of the wires 4 and 5 in these channels permits spot welding of the wires to the crimped wings at only one point without impairing the rigidity of the structure. The electrode members 2 and 3 may be provided with a circumferential rib 29 disposed adjacent the base of the electrode assembly structure. The rib 29 serves to reinforce the structure. This structural arrangement is particularly advantageous in the present application where a relatively small bulb I0 is used because it permits a more compact and sturdier mount assembly.

Another feature of the electrode assembly I, which is particularly advantageous for the reasons above-mentioned when a small bulb is used is embodied in the disposition of the assembly I with respect to the stem I. The lower edges II which form the base of the frusto-conical electrode assembly i extend down over the upper portion of the stem. This is an additional structural feature which characterizes the compact, sturdy electrode structure of our invention.

It has been the practice, whenever it was desired to incorporate a ballasting resistor in an electronic device to place it withinthe main body thereof and shielded from the discharge or in the base. When a device as small as the one shown and described in this application is concerned, neither of these two conventional methods proved very satisfactory. Therefore we have provided the stem 1 with an elongated throat 8, the walls thereof defining a suitable chamber within which a ballasting resistor I3 may be disposed, Thus the composite lead wire I2 comprises the wire Hi the resistor l3 and the wire H! which is connected through the stem press 6 to the electrode-supporting wire 5.

The mount which comprises the stem and electrode assemblies is sealed in a glass bulb ill, the inner wall of which is provided with a coating of fluorescent material H. The outer surface of the electrodes 2 and 3 is provided with a suitable coating 22 Of an oxide of one or more of the alkaline earth metals, such as barium peroxide for example. The inner surface of the electrodes 2 and 3 may be provided with a suitable coating 23 of zirconium or titanium metal powder to act as a getter during evacuation of the lamp 24 and to prevent emission from the inner surfaces of the electrodes 2 and 3 during operation of the lamp.

The conical design of the electrode assembly I is particularly adapted to the fluorescent type glow lamp. The projected apex of the complete cone surface, of which the frustum is a part is designed to fall within the bulb dimensions. This mount space and permitting a stem with an elongated throat to be used. The long-throated stem makes a sturdier mount and provides a suitable chamber for a resistor as part of one of the lead wires. I

What we claim is:

1. A mount assembly for an electric gaseous discharge devicecomprising a stem, 9. pair of electrode-supporting wires sealed in and projecting from said stem, and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure, the longitudinal peripheral edges of the electrodes being adjacent each other and spaced a short distance apart.

2. A mount assembly for an electric gaseous discharge device comprising a stem, a pair of electrode-supporting wires sealed in and projecting from said stem, and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure, the longitudinal peripheral edges of the electrodes being adjacent each other and spaced a short distance apart and the peripheral edges which define the base of said frusto-conical structure being disposed substantially below the top of said stem.

3. A mount assembly for an electric gaseous discharge device comprising 'a stem having a press and an elongated throat, a pair of electrode-supporting wires sealed in and projecting from said press, and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure, the longitudinal peripheral edges of the electrodes being adjacent each other and spaced a short distance apart.

4. A mount assembly for an electric gaseous discharge device comprising a stem having a' press and an elongated throat a pair of electrode-"supporting wires sealed in, and projecting from said press, and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure, the longitudinal peripheral edges of the electrodes being adjacent each other and spaced a short distance apart, and the peripheral edges which define the base of said frusto-conical structure bein disposed substantially below the top of said stem.

5. A mount assembly for an electric gaseous discharge device comprising a stem having a press and an elongated throat, a pair of electrodesupporting wires sealed in and projecting from said press, a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure, the longitudinal peripheral edges of the electrode being adjacent each other and spaced a short distance apart, a pair of lead wires connected through the stem press to said electrode-supporting wires and extending through a chamber defined by said elongated throat, and a resistor connected to one of said lead wires and disposed within the chamber defined by the elongated throat of the stem.

6. A mount assembly for an electric gaseous discharge device comprising a stem having a press and an elongated throat, a pair of electrodesupporting wires sealed in and projecting from said press, a pair of electrodes mounted on said wires, said electrodes defining a substantially i a chamber defined by said elongated throat, and

a resistor connected to one of said lead wires and disposed within the chamber defined by the elongated throat of the stem.

7. An electric gaseous discharge device comprising a glass envelope, a stem sealed in said envelope, a pair of electrode-supporting wires sealed in and projecting upwardly from said stem into the chamber defined by said glass envelope and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure in which the longitudinal peripheral edges of the electrodes are adjacent each other and spaced a short distance apart, and the projected apex of the cone-like structure falls within the chamber defined by the glass envelope.

8. An electric gaseous discharge device comprising a glass envelope, a stem sealed in said envelope, a pair of electrode-supporting wires sealed in and projecting upwardly from said stem into the chamber defined by said glass envelope, and a pair of electrodes mounted on said wires, said electrodes defining a substantially frustoconical structure in which the longitudinal peripheral edges of the electrodes are adjacent each other and spaced a short distance apart, the peripheral edges which define the base of said frusto-conical structure are disposed substantially below the top of said stem, and the projected apex of the cone-like structure falls within the chamber defined by the glass envelope.

9. An electric gaseous discharge device comprising a glass envelope, a fillingof an inert gas in said envelope, a coating of luminescent mate rial on the inner wall of said envelope, a stem sealed in said envelope, a pair of electrode-supporting wires sealed in and projecting upwardly from said stem into the chamber defined by said glass envelope and a pair of electrodes mounted .tudinal peripheral edges of the electrodes are adjacent each other and spaced a short distance apart, the peripheral edges which define the base stantially below the top of said stem, and the" projected apex of the cone-like structure falls within the chamber defined by the glass envelope.

11. An electric gaseous discharge device comprising a glass envelope, a filling of an inert gas in said envelope, a coating of luminescent material on the inner wall of said envelope, a stem sealed in said envelope, a pair of electrode-supporting wires sealed in and projecting upwardly from said stem into the chamber defined by said glass envelope and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure in which the longitudinal peripheral edges of the electrodes are adjacent each other and spaced a short distance apart, and the projected apex of the cone-like structure falls within the chamber defined by the glass envelope, and a coating of electron-emissive material on said electrodes.

12. An electric gaseous discharge device comprising a glass envelope, a filling of an inert gas in said envelope, a coating of luminescent material on the inner wall of said envelope, a stem sealed in said envelope, a pair of electrode-supporting wires sealed .in and projected upwardly from said stem into the chamber defined by said glass envelope, and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure in which the longitudinal peripheral edges of the electrodes are adjacent each other and spaced a short distance apart, the peripheral edges which define the base of said frusto-conical structure are disposed subon said wires, said electrodes defining a substantially frusto-conical structure in which the longitudinal peripheral edges of the electrodes are adjacent each other and spaced a short distance apart, and the projected apex of the cone-like structure falls within the chamber defined by the glass envelope.

10. An electric gaseous discharge device comprising a glass envelope, a filling of an inert gas in said envelope, a coating of luminescent material on the inner wall of said envelope, a stem sealed in said envelope, a pair of electrode-supporting wires sealed in and projecting upwardly from said stem into the chamber defined by said glass envelope, and a pair of electrodes mounted on said wires, said electrodes defining a substantially frusto-conical structure in which the longistantially below the top of said stem, and the projected apex of the cone-like structure falls within the chamber defined by the glass envelope, and a coating of electron-emissive material on said electrodes.

ERWIN F. LOWRY. ARNOLD L. PEACOCK. WILLIAM E. LEYSHON.

REFERENCES cr rEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,816,690 Moore July v28, 1931 1,879,158 Foulke Sept. 2'1, 1932 1,965,586 Foulke-- July 10*, 1934 2,298,581 Abadie Oct. 13, 1942 2,409,769 Leyshon Oct. 28, 1946 2,413,650 Peacock Dec. 31, 1946 FOREIGN PATENTS Number Country Date 411,683 Great Britain June 14, 1934 819,881 France July 19, 1937

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