US2155816A

US2155816A - Starting and operating circuit for gaseous electric discharge devices

Info

Publication number: US2155816A
Application number: US234710A
Authority: US
Inventors: Maynard A Babb
Original assignee: Duro Test Corp
Current assignee: Duro Test Corp
Priority date: 1938-10-12
Filing date: 1938-10-12
Publication date: 1939-04-25
Anticipated expiration: 1956-04-25

Description

April 25, 1939. M A BABB 2,155,816

STARTING AND OPERATING CIRCUIT FOR GASEOUS ELECTRIC DISCHARGE DEVICES Filed Oct. 12, 1958 Patented Apr. 25, 1939 UNITED STATES PATENT OFFICE STARTING AND OPERATING CIRCUIT FOR GASEOUS ELECTRIC DISCHARGE DE- York Application October 12, 1938, Serial No. 284,710

2 Claims.

This invention relates to gaseous electric discharge devlces, and more particularly to method and means for starting and operating devices oi the above type having thermionic electrodes.

The customary starting mechanisms for vapor lamps requiring heated cathodes comprise timedelay relays or bimetallic thermal strips or other devices operated by separate heating elements, or comprise elements which require additional voltage and which rob the lamps of some of the necessary starting voltage, unless a transformer is used in the circuit. For a vapor lamp required to start at the lowest possible voltage, resonant circuits, condensers, or the like, are often employed to give the lamp enough additional voltage to enable it to start.

The principal object of my invention is to provide a simple, novel, and efllclent starting mechanism for vapor lamps embodying in one simplified unit means to provide the requisite highfrequency impulses and starting voltage without use of a transformer, also to provide means for removal of the current from the thermionic electrode or filament circuit after the arc strikes, and to provide means in said circuit which will operate as a ballast mechanism for limiting the current to the lamp after the arc strikes.

The accompanying drawing illustrates diagrammatically a vapor lamp connected in my novel starting and operating circuit, and I will explain the invention with reference to the drawing which illustrates one practical embodiment thereof, to enable others familiar with the art to adopt and use the same; and will summarize in the claims, the essential novel featuresmf the invention, and the novel combinations of parts, for which protection is desired.

As shown, the gaseous electric discharge device comprises a vapor lamp I having a gaseous filling such as neon, or the like, and provided with

thermionic electrodes

2 and 3, which may be formed of a roll of electron emissive material such as barium oxide, surrounding a heater filament, one terminal of electrode 2 being connected by a lead 4 to one terminal 5 of a commercial source of alternating current which may have the usual line voltage of 110-120 volts. The other terminal of electrode 2 is connected by lead ii to a movable armature I normally held by gravity or by spring means 8 in engagement with a fixed contact 9, which contact is connected by lead ill to one terminal of electrode 3. The other terminal of electrode 3 is connected by lead II to one terminal i2 of the coil it of an electro- 55 magnet it which forms a reactor coil, the other (CL "F terminal I! oi which coil is connected by lead It to the other terminal to of the power source. A hand operated switch I! may be connected in either lead I or ii. Thus when switch i1 is closed the electrodes are initially connected directly in series with the power source 5, to, due to the fact that armature 'i is normally in contact with contact ii.

In the circuit shown in the drawing, when the line voltage 5-511 is first applied by closing switch H, the current flows through the thermionic electrodes 2 and I which are connected in series, the current continuing through the reactor coil l3 in returning to source 5-511. When the current passes through the reactor coil ii a magnetic field is set up in the iron core of magnet it which pulls the armature 1 down and breaks the electric circuit at the contact 9. This action causes the magnetic field in the iron core to reduce until the spring Ii can again raise the armature I against the contact 9. This process is rapidly repeated until the

electrodes

2 and 3 are sufficiently hot so that the high frequency caused by the opening and closing of the contacts I and 9 together with the voltage across the

electrodes

2 and 3, when the contact 9 is open, causes an arc to be established between the electrodes. When the arc occurs, the armature I is maintained in down position to open the contact 9, due to the continuous arc current passing through the reactor coil i3, which coll will then operate as the current limiting device for the arc during the continuous operation of the lamp. If the arc should cease the reactor coll l3 would de-magnetlze and spring 8 would lift armature I again into contact with contact 9, and the above operation would repeat itself to reestablish the arc.

The novel features of my circuit are the incorporation in one simplified unit, of the mechanism for producing the high frequency impulses and increased available voltage at the electrodes 2-3, without using a transformer; also the mechanism for opening the series circuit of the thermionic electrodes 2-4, after the are strikes; also the use of the reactor coil of the circuit opening mechanism as a ballast mechanism for limiting the arc current of the lamp during its continuous operation; also the incorporation of the starting mechanism and lamp operating ballast mechanism in a single unit, which allows high frequency voltage impulses to be impressed between the electrodes of the lamp, facilitating its starting.

I claim:

1. A starting and operating circuit for gaseous electric discharge devices having thermionic electrodes, comprising leads connecting the electrodes in series with a source of alternating current; a normally closed switch in said lead between the electrodes; and electromagnetic means including a coil in one of the leads from the source adapted when energized to open said switch, whereby the coaction between the switch and coil will provide the high frequency impulses and voltage necessary to heat the electrodes up to the point of arcing, whereupon the arcing current passing through the coil will maintain the switch open, and the coil will serve to ballast the arcing current.

2. A starting and operating circuit tor gaseous electric discharge devices having thermionic electrodes, comprising an armature; a fixed contact means for normally maintaining the armsture and contact in engagement; a lead including the armature and contact connecting the electrodes in series; other leads connecting the respective electrodes with a source of alterating current. electro-magnetic means adapted when excited to disengage the armature and contact; said electro-magnetic means being interposed in one of said other leads, whereby the coaction between the armature and electro-magnet means will provide the high frequency impulse and voltage necessary ior heating the electrodes up to the point of arcing, whereupon the arcing current passing through the electro-magnetlc means will maintain the armature and contact disengaged, and the electromagnetic means will serve to ballast the arcing current.

MAYNARD A. BABE.

DISCLAIMER 2,155,8l6.-Maymtrd A. Babb, North Bergen, N. J.

CIRCUIT FOR Gssnoos ELECTRIC DISCHARGE DEVICES.

STARTING AND OPERATING Patent dated April 25, 1939. Disclaimer filed March 30, 1940, by the inventor; the assignee.

Duro Test Corporation, consenting. Hereb I Gazette April 23, 1.940.]

enters this disclaimer of

claims

1 and 2 of said patent.