US2392845A

US2392845A - Means for controlling the operation of luminescent lamps and other electrical apparatus

Info

Publication number: US2392845A
Application number: US412492A
Authority: US
Inventors: Foerste William
Original assignee: EUGENE A QUARRIE
Current assignee: EUGENE A QUARRIE
Priority date: 1941-09-26
Filing date: 1941-09-26
Publication date: 1946-01-15
Anticipated expiration: 1963-01-15

Description

Jan. 15,1946. w. FOERSTE 2,392,845

MEANS FOR CONTROLLING THE OPERATION OF LUMINESCENT LAMPS AND OTHER ELECTRICAL APPARATUS Filed Sept. 26, 1941 3 Sheets-Sheet 1 I 40 F 1/45 n n c I rn n n v u u u u INVENTOR.

- ML L/AMFOERS TE ATTQRNEY.

Jan. 15, 1946. w FOERSTE 2,392,845

- MEANS FOR CONTROLLING THE OPERATION OF LUMINESCENT LAMPS AND OTHER ELECTRICAL APPARATUS 7 Filed Sept. 26, 1941 3 ShG'hs-Sheet 2 INVENTOR. W/LL/AM FOE/P5 rs ATTORNEY.

Jan. 15, 1946. w] FOERSTE 2,392,845

MEANS FOR CONTROLLING THE OPERATION OF LUMINESCENT LAMPS AND OTHER ELECTRICAL APPARATUS Filed Sept. 26, 1941 3 Sheets-Sheet 3 147 INVENTOR.

ATTORNEY.

. former, whereby solenoid means alone, or when Patented Jan. 15, 1946 TION OF LUMINE OTHER ELECTRIC William Foerste, Pelham Manor, N.

SCENT LAMPS AND AL APPARATUS Y., assignor of one half to Eugene A. Quarrie, Scarsdaie,

Application September 26, 1941, Serial No. 412,492 9 Claims. (01. 315-278) The invention relates to the operation of raregas-fllled lamps of the ordinary luminescent type as well as of the fluorescent type, wherein to effect the illumination an electrical discharge is provided between electrodes at opposite ends of an envelope containing a suitable gaseous medium. These lamps are usually operated by connecting the electrodes to the secondary of a transformer, the secondary voltage having a high open-circuit value. The transformers, as a rule, are constructed to have a high reactance, the gaseous tube element requiring a relatively high initial voltage to ionize the contained gas but only a relatively low operating voltage thereafter. Control of the intensity of illumination has heretofore been attempted by including in circuit with the primary of the operating transformer large value impedance which, of course, reduces the applied voltage. This results, generally, in inefllcient and unsatisfactory operation of a lamp, particularly due to excessiveflickering.

It is an object of the present invention to provide means, including a high reactance transthe required high initial voltage will be afforded and at the same time variations in the output of the secondary of the transformer may be effected within the primary circuit to control,

erated from the transformer.

A further object of the invention is to maintain for example, the intensity of the illumination provided by a luminescent tube opvide a simple and rugged construction by embodying the control features as an integral part of the transformer.

The invention has for an object, also, to provide means in connection with the novel transformer arrangement for correcting the power factor and to preserve at the same time against welding, pitting, and general deterioration the control contacts employed for varying the output of the transformer. 1

In carrying out the invention, there is associated with the usual transformer core means such as a solenoid or one or more supplementary or auxiliary cores inviting magneticleakage. Such associated in a novel manner with a core or cores, directs the flux produced in the transformer core by the primary winding of the tansformer respondingly the output of the seconday winding of such transformer. Suitable switching means to control cor- 7 56 core 20 extends within the main core are associated with these control or flux-directing windings to secure the desired output, the

whole arrangement being such, however, that a open-circuit secondary Fig. 2 illustrates a modification in the arrangement.

Fig. 3 illustrates an auto-transformer type embodying the novel arrangement. K Fig. 4 illustrates the. control arrangement for multi-tube operation from a transformer common thereto.

Fig. 5 illustrates a further modification.

Fig. 6 illustrates atom of transformer control similar to that-shown in Fig. 1, but provided with a novel arrangement for power-factor correction.

Referring to the drawings, more particularly Fig. 1 thereof, 1 0 designates the closed core structure of a transformer, which may be constructed in the usual manner of laminated iron, said core afiording a closed magnetic circuit. -A primary winding II is provided thereon and derives its power from the main I2 through a lead l3 and a switch-arm I 4. 'A secondary winding I5 is also provided on the core, and is shown as connected directly to the electrodes l6 and I1, either of the hot or cold type. of a luminescent lamp including a transparent envelope I 8. Winding I 5 is thus in inductive relationship to the primary and supplies the lamp. with the requisite voltage for its proper operation. In the operation of these lamps it is understood that an initially high voltage must be supplied :by the secondary to effect the ionization of the rare gas in the envelope, this voltage then dropping to a much lower sustaining or working value when the lamp is in.

service. The novel arrangement hereinafter set forth, however, affords at the same time a ballast to prevent overheatingof-the tube and disintegration of the tube elements, thereby maintaining the current density and the light intensity.

In accordance with the invention, an auxiliary structure to position indicated afford a high leakage reactance element or magnetic shunt, there being provided over said core a winding divided, for example, into two coil portions 2| and 22. As shown, the winding is divided midway to this end by connection of the lead 23 from the primary ii substantially to the midpoint of the said winding. Respective leads 24 r the switch-point 30. In the latter instance, the

transformer will operate in the usual manner with core introducing a certain amount or reactance due to the normal magnetic leakage provided thereby. However. the amount or this reactance may be respectively increased or decreased accordingly as one or the other or the coils 2| or 22 is energized by setting the switcharm i4 to switch-point 28 or switch-point 28, re-

spectivelythe one coil being subtractive in its effect, developing an opposing flux, and the other additive, developing a like flux, with respect to the reactance normally introduced by the core 20.

Tue magnitude of the flux oi the core may thus be varied and while this will accordingly vary the current supplied, the open-circuit voltage delivered by the secondary II remains substantially constant in accordance with the requirements of the lamp and the relationship between the number of primary and secondary turns. The dimensions or the core, more especially its length, will be according to the requirements of the variation desired and the core may be omitted entirely in some instances and merely the solenoid utilized. The leakage eflectoi the core will then, of course, be missing and only the solenoid is effective to provide for leakage and in accordance with the current flowing in the primary winding.

This particular type of control lends itself, also, to the production or flasher apparatus or light beacons and in which it is possible, moreover, to provide automatically consecutive illuminations of diflerent intensities. For example, a thermostatic circuit-controiling device 35 may be included in series in a circuit across the contact points as and 8D, and there is included in the two

leads

38 and 31 of said circuit a switch 38 whereby the eflect of the thermostatic device may be introduced or dispensed with accordingly as the switch 38 closes the circuit or opens the same. When the switch 38 is in the closed position, and the contact 88 of thermostatic device 35 also is in position to close the said circuit at this contact, one of the windings on core 2! is by-passed and opposes the core flux. The current supplied to the secondary l5 and the lamp connected thereto will thenbe or one intensity, switch-arm i4 having been moved first to the in the broken lines, on switchpoint 2!. This connects the primary Ii directly with the supply main l2; and current flowing through the leads -21 will eventually cause the thermostatic device to operate to open said by-passing circuit at the contact as thereof.

This latter circuit is then ineilective and the current to the primary ii must also now through aselected one! the windings on cos-e20, in the present instance the winding 2|. This will afford v a secondary current of a diflerent value with corresponding change in the light intensity of the lamp.

Various combinations, of course, are possible by providing for diilerent connections oi the ther mostatic device to other switch-points, as will be readily understood; and in instances where the auxiliary or leakage core contains but a single winding, a simplified arrangement becomes possible involving cutting out merely such winding alternatively with its inclusion with the primary. Fig. 2 illustrates an additional form of transformer construction in which the main core structure includes a cross-core 40 upon which the primary winding 4| as well as the secondary winding 42 are located. In addition, two auxiliary cores or high-

leakage reactance elements

43, 44 are provided extending midway of the transformer structure toward the cross-core 40. Each one of these

latter cores

43 and 44 is provided with a corresponding winding 45 and 46, respectively, which are arranged to be placed alternatively in circuit with the primary winding 4!. This may be effected by the switch-arm connected to one lead Ill of the supply main 52, the other lead 58 being connected directly to one terminal of the primary winding 4|. The other terminal of said primary winding is connected through lead 54 to a switch-point 55, as well as to one terminal of the winding 46 whose other terminal is connected through lead 58 to a switch-point 51. This latter terminal of the winding 46 also is connected to one terminal oi the winding 45 whose other terminal is connected through lead 58 to switch-point 59.

In accordance with the position of arm ill with respect to the switch-points 55, l1, and 59, various currents will be supplied to secondary winding 42 for illumination of the lamp 60 at diflerent intensities.

An auto-transformer arrangement is indicated in Fig. 3 as equipped with the current-modifying circuits hereinbetore described. As shown, a primary winding 84 red from the main through leads 66 and O1 energizes the secondary comprising the separated halves 88 and 69 which ailord the supply current to energize lamp 10. A condenser -'|l across the secondary. minimizes the power factor loss of the power supply device, as well as facilitating starting.

A switch-arm 12 when positioned on the switchpoint 13 eiiects this direct connection of main 85 with the primary 64, other switch-points 14 55 and I! being provided for ailordingdiflerent current values as set up in the secondary coil 8-H. For example, two auxiliary cores l6 and 11, alfording high leakage reactance, are provided with corresponding windings l8 and I8, respectively.'

One terminal of the former winding is connected to the lead 88. the other terminal of said winding being connected by lead with the switchpoint 14. This lead 84 is also connected with one terminal of the winding 19 whose other terminal is connected by lead 8| with the switch point II. when the switch-arm I2 is positioned on switch-point 14, only the winding II will be effective to alter the secondary output; whereas, when located on the switch-point Ii, both windings II and I! will be included in series with the primary winding 04. It the windings It, I! be arranged such that the direction oi ilow will eilect magnetization of the respective cores in opposition to the leakage elects, a regulating eiiect on the tube supply current results which ment of an additional rectifier I31.

primary circuit of transformer I26 is energized prevents overheating and resultant rapid destruction of the said tube.

In Fig. 4 is indicated an arrangement for multiple-lamp operation simultaneously and in a like amount by the secondary output variations.v The ture, but the windings thereon are diflerently arranged from those indicated in Fig. 3 for the corresponding elements.

Each

core

90 and 91 is provided with a double winding, the former having the windings I and IOI, and the latter the windings I0'2.and I03. The particular switching arrangement in this embodiment includes the double-pole switch-arm I04 and the corresponding sets of switch-points I05, I06, 101, and I08, I09, IIO.

When arm I04 isin the position indicated, the light of one of the

tubes

94, 96 is dimmed and of the other intensified; and when moved to the position indicated by the broken lines, the reverse action takes place. In the intermediate position, viz: when the points I06 and I09 are bridged by the arm I04, both tubes operate at the same intensity. Under all the conditions, the primary load,'however, remains substantially constant, which is not the case in the embodiments herelnbefore described. I

In Fig. 5 there is illustrated a further modification in the flasher arrangement of control and wherein the modified illumination efiect is imparted gradually rather than instantaneously at its full value. Thus, lamp I I5 is operated from the secondary II6 of transformer II1 whose primary H8 is connected to the main II9. There is provided, also, an auxiliary leakage core I with the two windings I2I' and I22 thereon whose efiects on the core are additive. These windings are. arranged to be energized automatically through a circuit I23 including a thermostatic device I24 energizing the primary winding I25 of a transformer I26. There is included in this circuit, also, a ballast resistance I21 fair the purpose hereinafter set forth.

A lead I connects the mid-point,'for example, of the winding on, core I20 to'on'e lead of the main H9 and from the other lead of the main a lead I 3| is connected to a secondary winding I32 on the transformer I26. The respective ends of the windings I2I and I22 are connected through lead I33 to another secondary winding I36 of transformer I26 and to the plate of a thermionic rectifier I 34 through a lead I35. The

of the two rectifiers increase, their resistances correspondingly increase, resulting in lesser primary current flow in transformer I26 and reduced voltage drop across the ballast resistance I21. Initially, this resistance serves to reduce materially the current flow through the cold filaments and thus cause the variation inlight intensity of lamp Hi to be applied gradually.

Apparatus of the nature hereinbefore set forth may readily be corrected for power factor loss i by bridging a condenser across the primary coil and associated auxiliary core winding. As indicated inF'ig. 6, the transformer I40 is provided with'a primary MI and secondary I42 which energizes the lamp I43. The auxilary core I44 carries the winding I45 from which a tap is taken through lead I46 to one electrode of a condenser I41, the other electrode being connected through lead I48 to a tap I49 of the primary. By this expedient,these taps, in providing an increased voltage, allow ofthe us of a smaller capacity condenser. Moreover, the tap portions may be in the nature of bufier coils to momentarily check the surge of condenser discharges on closing of the circuit through a switcharm I50 to the switch-points I5I and I52, thereby obviating welding of the arm to a point.

I claim:

1. The combination with a luminescent discharge lamp of the gas-filled type operating at a substantially constant ionization voltage; of means to vary at substantially constant opencircuit voltage the power supplied to the lamp to'alter the intensity of illumination thereof, including a transformer having a closed magnetic core, only one primary and at least one closely coupled secondary connected to the lamp; and a high reluctance variable reactor in single-acting shunt magnetic relationship with said core and including a coil in series with the primary, said reactor being magnetically positioned between the primary and secondary and separated from the core by a non-magnetic gap to invite magnetic leakage and to divert flux from a portion of said core.

2. 'I'hecombination with a luminescent discharge lamp of the gas-filled type operating at core, only one primary and at least one closely windings I32 and I36 serve to energize respectively the filament of rectifier I34 and the fila- When the a substantially constant ionization voltage; of means to vary at substantially constant open circuit voltage the power supplied to the lamp to alter the intensity of illumination thereof, in'-' cluding a transformer having a closed magnetic coupled secondary connected to the lamp; a high reluctance reactor in single-acting shunt magnetic relationship with said core and including a coil in series with the primary, said reactor being magnetically positioned between the primary and secondary and separated from the core by a non-magnetic gap to invite magneticv leakage and to divert flux from a portion of said core; a source of electrical energy supply; and means for connecting alternatively thereto either said single primaryor said primary' in series with the said reactor.

3. The combination with a luminescent discharge lamp of the gas-filled type operating at a substantially constant ionization voltage; of means to vary at substantially constant opencircuit voltage the power supplied to the lamp to alter the intensity of illumination thereof, in-- cluding a transformer having a closed magnetic core, only one primary and at least one closely coupled secondary connected to the lamp; high reluctance reactor means in single-acting shunt magnetic relationship with said core and magnetically positioned between the primary and secondary and separated from the core by a nonadapted to divert flux in phase with the transformer flux; a source of electrical energy supply; and switching means for connecting alternatively thereto either the winding of said single primary or the winding of said primary in series with selected taps oi the winding of the said reactor.

4. The combination of claim 1, wherein a means is provided for automatically controlling the reactor means.

5. The combination claim 3. wherein a circuit is provided for short-circuiting the reactor means winding, and a circuit-interrupting means is included therein.

6. The combination of claim 1, wherein a condenser is connected across the lamp, and an inductance is included between the said condenser and each terminal of the lamp.

7. The combination of claim 1, wherein a condenser is connected with the primary and with the reactor means.

8. The combination-o! claim 1, wherein the primary has an auxiliary winding constituting with the primary winding an autotransiormer, and a connection is provided from the free end of the auxiliary winding to the reactor means with a condenser included in series in the said connection.

9. The combination with a luminescent discharge lamp oi. the gas-tilled type operating at magnetic circuit, only one primary, and at least primary.

WILLIAM FOERS'IE.