US2265980A

US2265980A - Electrical energy regulating means

Info

Publication number: US2265980A
Application number: US226429A
Authority: US
Inventors: Berger Paul
Original assignee: THORDARSON ELECTRIC Manufacturing COMPAN
Current assignee: THORDARSON ELECTRIC MANUFACTURING Co; THORDARSON ELECTRIC Manufacturing COMPAN
Priority date: 1938-08-24
Filing date: 1938-08-24
Publication date: 1941-12-16
Anticipated expiration: 1958-12-16

Description

Dec'. 16, 1 941. P. BERGER ELECTRICAL ENERGY REGULATING MEANS 2 sheets-sneer 1 Filed Aug. 24, 1938 y Uv,

QU i.. fe E 4 MMM? MHP .57

Dec. 16, 1941. FI BERGER 2,265,980

ELECTRICAL ENERGY REGULATING MEANS Filed Allg. 24, 1938 2 Sheets-Sheet 2 4' 75 g 75 5r u' i i 5./

104A lo Patented Dec. 16, .1941

ELECTRICAL ENERGY BEGULATING MEANS Paul Berger, Chicago, Ill., Electric Manufacturing a corporation of Illinois Application August 24, 193s, serial Nc. 226,429

(ci. 17e- 124) 6 Claims.

This invention relates generally to the art of regulating the electrical energy supplied to a. load circuit. It is directed especially to illumination, and particularly to illumination by means of gasecus discharge tubes, and to the provision of means for regulating the intensity of illumination from such tubes.

Gaseous discharge tubes are used to provide illumination for lighting purposes and for signs. Lighting may be accomplished by combining light from separate tubes emitting dilferently colored light to produce a White light which is suiciently similar to natural daylight to be satisfactory for lighting purposes. vIn this art it is frequently desirable to be able to adjust the intensity of the light of the different colors so that the resulting composite light has the proper shade of white for the best lighting effectiveness. For example, the combination of a neon tube which emits an orange-red colored light, and a closely associated mercury vapor tube having a coating of green fluorescing salts upon its interior Walls, produces a white light. The proportion of illumination supplied by each tube determines the color of the composite light, and ifthis is varied within wide limits the resultant light varies from one which is substantially green through varying shades in which the green becomes less predominant and the light takes on the character of a white light with a greenish cast, through white, to White with a reddish cast and finally to a light which is substantially orange-red. If no means are provided for regulating thequantityV or illumination from the differently colored tubes, they must be associated atI the outsetwith the proper proportion, which is often attended with difliculties. Furthermore, the colored light from a tube having a coating of fluorescing salts frequently undergoes a change of intensity With use, so that proportions which may be satisfactory at the outset may become unsatisfactory and produce a definite shade of green or red after the light has been in use for a time. Under such conditions it may be necessary to add one or more tubes to supply a den-V ciency. It is apparent that it is highly desirable assignor to Thordarson Company, Chicago, Ill.,

varying the colors and the intensity. The sign may be composed of one, or of a number of colors, and it may be desired to vary the color or the intensity continuously or intermittently, or merely to adjust them to some condition which will thereafter remain constant.

Means have been provided heretofore for adjusting the intensity of illumination of electrical lighting sources by varying the impedance in the electrical supply circuit. However, dlihculties attend the use of such means with gaseous discharge tubes. Such tubes require a high initial or striking voltage and a relatively low operating voltage, as is well known, and the interposition of impedance in the supply circuit frequently causes the supply voltage to be lowered below the required initial voltage, especially since the system is usually constructed so as to provide a voltage not greatly in excess of such initial voltage. The applied voltage decreases to zero value twice in each complete cycle of the alternating current supply and during these times the tubes are inoperative and open circuit conditions Aexist and the operation of the tube must be initiated twice during each cycle. Consequently flickering of the tubes takes place, and sometimes complete extinguishment, when the applied voltage on open circuit is not adequate to meet the initial voltage requirements of the tube.

It is the general object of the invention to provide an improved means for regulating the energy supplied to a load circuit.

It is the specinc object of the invention to provide an improved means for regulating the intensity of illumination of gaseous discharge tubes which is simple and economical, and is convenient in operation, requiring only the manipuiation of a movable member, and not requiring the addition of tubes to supply a deciency of a color.

It is a further object of the invention to provide such a regulating means which overcomes the flickering and extinguishment mentioned above and provides an even continuous illuminato have a means for adjusting the color proportions in a more convenient manner,

Where surfaces and objects such as the ceilings of theatres, the sprays of fountains, and the like, are illuminated in color by` indirect light, it is frequently desired to vary the intensity and the color to obtain pleasing effects. Similarly with signs, for advertising and other purposes, pleastion at all intensities down to the condition in which the' light is substantially extinguished.

It is a still further object of the invention to provide a regulating means which accomplishes 4a smooth, continuous intensity change rather ing and also spectacular eects are obtained by than an irregular, step-by-step change.

To describe the invention briefly, the supply circuit for gaseous discharge tubes usually contains a transformer of the so-called high-leakage reactance type, in which there are magnetic shunts between the primaryv and secondary windings, through which shunts the magnetic flux leaks, or by-passes, the secondary winding. The transformer may be of the shell or core type both of which are well known, and in which fixed stationary windings surround one leg of the magnetic core, called the winding leg, and the shunts are located in the spaces between the winding leg and the other leg or legs. In accordance with this invention, one of the windings of the primary and secondary windings is movable along the Winding leg into positions at varying distances from the other. As the distance between the windings is increased the proportion of the flux which follows the leakage path through the shunts and the air gaps adjacent the shunts becomes greater with the result that the flux which follows the useful path, that is, which threads the secondary winding, is proportionately less and the illumination of the tubes which are connected in the output of the secondary winding is -correspondingly decreased. While this is the4 effect during that portion of the alternating current wave cycle during which the tubes are op erative, that is, the active portion of the cycle,

the variation of the distance between windings produces little or no such effect during the inactive portion of the cycle. At that instant the relative reluctance of the leakage path and the useful path is substantially the same regardless of the distance apart of the windings. As a result the initial voltage is not affected to any substantial degree by the movement of one of the windings, and the requisite initial voltage is always available and applied to the tubes. It has been found in practice that the windings may be moved so far apart that the illumination is only barely visible while a steady light without any flickering is maintained. In a modication l of the regulating means, the shunt members of the transformers, rather than one of the windings, are movable to vary the leakage reactance.

In the drawings:

Fig. 1 is a perspective view, partly diagrammatic, of several colored gaseous discharge tubes and a supply circuit therefor including the means of this invention for regulating the intensity of illumination of the tubes;

Fig. 2 is a graphic representation of the variation of illumination intensity provided by the invention, with particular reference to the combination illustrated in Fig. 1;

Figs. 3 and i illustrate diagrammatically two modified forms of theintensity regulating means of this invention;

Fig. 5 is a fragmental, sectional view of a modication of the intensity regulating means in.

which the shunt members of the supply transformer are movable to vary the leakage reactance said view being taken along line 5 5 of Fig. 6;

Fig. 6 is a sectional view, partly diagrammatic, taken along 6 6 of Fig. 5; and

Figs. 7, 8 and 9 are diagrammatic plan views showing three further modifications of the invention.

In Fig. 1, tubes III and I I vare diierently colored gaseous discharge tubes, which may be of any desired color. For purposes of representation, tube ISI is a neon tube emitting an orange-red light, and tube II is a mercury vapor discharge tube having a coating of green fluorescing salts,`

emitting a light which is predominantly green but also contains the visible blue of mercury vapor. The tubes are connected separately toeach of the two secondary-windings I2 and I3 of the supply transformer I4. VThe primary winding l5 of the transformer is connected to a suitable source of alternating current electrical energy I6 by means of conductors II.

rl'he transformer I4 comprises a closed magnetic core composed of steel laminations. The core is of the so-called shell type, comprising an elongated central or winding leg I8 and two outer legs I3 and 2D which are spaced from the central legk I B in the usual manner, the legs all being connected together at their ends by the end portions 2I and 22. The laminations are fastened together into a unitary structure by means ofiron straps Z3vwhich extend along the top and bottom surfaces of the legs and are fastened together by means of rivets 24 and end bars 25. The latter also serve as feet for supporting the transformer and are provided with openings 26 by means of which the transformer may be fastened in posi- 20 tion upon a suitable support.

The windings all'surround the winding-leg I8 and are preferably separated from. the adjacent portions of the core'bymembers 2 of electrical insulating sheet material. The secondary winding I2 is fixed in position adjacent the end portion 2| of the core. l The inner end of this winding is connected to av conductor 28 which isy broughtrout and clamped between laminations of the core as shown, and the other end of the winding is connected to a conductor 29 which is connectedv to one terminal of the neon tube III. The other secondary winding I3 is arranged similarly at the opposite end of the core. The inner end of this winding (not shown) is connected to the core in the same manner as described in connectionvwith winding I2, and the other end of the winding is connected to' one terminal of mercury tube II by conductor 31. The other terminals of tubes I0 and II are connected to the core by conductors 3d and 35 respectively, and the core is connected to the ground as indicated at 36. This is .a preferred method of connection, but the two terminals of each tube may be connected to the two terminals of each winding respectively, as will be described hereinafter, if that is desired.

Shunt members 30 of. steel laminations are positioned in the spaces between the central leg I8 and the outer legs I9 and A2li adjacent the side of secondary coil I2 and are separated from said core legs by members 32 of thin electrical tightly to maintain them in fixed position. In the same manner shunt members 33 are arranged adjacent the other secondary Winding I3. The laminations of the shunt members are fastened together by rivets 3|.

The secondary windings are spaced apart a distance which is greater than is usual in transformers known heretofore, and thesections of the core legs between the shunt members 30 and 33 are relatively elongated. The primary winding I5 is mounted slidably upon the winding leg I3, andis readily slidable from a position adjacent shunt members 3D to one adjacent shunt members 33, that is, to positions at varying distances from the secondary windings. The heads of rivets 2d arecountersunk so as not to interfere With the sliding vmotion. When. the transformer is operative in supplying energy to the load circuit there are magnetic forces of repulsion between the windings, and the movable primary winding is mounted upon winding leg portion of the winding at one side thereof, said member having a threaded opening through which a clamping bolt 48 may pass and serve to clamp the said member Il to .the winding leg I8.

.The shunt members 30 and 33 prvide leakage paths through which the magnetic flux may bypass theportions of the core which are beyond them, these latter portions being called the secondary core portions, .the balance, or middle portion, of the core being vcalled the primary portion. The members of thin, insulating sheet material 32 provide air gaps between the shunt members and the core legs, and these are of a thickness to regulate the magnetic reluctance of the leakage paths to be greater than the reluctance of the secondary core portions on open circuit. Upon the closing of the secondary circuit, the current owing therein causes an increase in the reluctance of the secondary core portions whereby a proportion of the magnetic -flux follows the leakage paths, this proportion becoming greater as the current in the secondary windings becomes greater.

mary winding' I5 and secondary winding VI3 is relatively large because more area of legs I3, I9

and'ZIl are exposed to each other across the intervening air gaps, and the reluctance of said leakage path is decreased while that of the useful( path 45 is increased because of the increased distance from the primary winding. As a resuit, a greater proportion of the iiux follows the leakage path. 'Ihe phenomenon may also be expressed by saying that the coupling between the primary winding I5 and the secondary winding I3 becomes weaker as the two windings are In operation, the system is energized by clos- I ing switch 38 in the alternating current energy supply circuit. The initial flux substantially-all passes through the secondary core portions and produces a striking voltage in the output of the secondary winding sufficient to initiate operation of the tubes. Immediately the impedance of the tubes decreases greatly and the current through them and through the secondary winding increases. This current opposes the iiux in the secondary core portion and increases the reluctance of such portion whereby a substantial proportion of the flux by-passes it and follows the leakage path through the shunt members and adjacent air spaces. The path of the initial flux and of the useful flux while the tubes are operative is indicated by the dotted lines and the path of the leakage flux during operation of the tubes is indicated by dotted lines 46.

As stated heretofore the primary winding I5 is readily slidable along the winding leg I8 into positions at varying distances from the sf tondary windings I2 and I3, this sliding movement being accomplished by hand or other suitable mechanical means. The position of the primary Winding I5 does not have any appreciable effect upon the distribution of the initial or open circuit flux, and this remains substantially constant under conditions whereby substantially all of it passes through the secondary core portions. As a result, the initial or striking voltage induced in each of the secondaries remains substantially the same regardlessy of the position of the primary winding, and is always adequate to initiate operation of the tubes. As a result the tubes operate steadily under all conditions of intensity. However, during the time that the secondary windings are operative, and closed circuit conditions obtain, theproportion of iiux which by-passes each secondary winding is proportional to the distance between that secondary winding and the primarywinding. In Fig. 1 the primary winding is'shown as being farther from secondary winding I3 than from secondary winding I2.V The leakage path 46 between primoved farther apart. The result is that the intensity of illumination of mercury vapor tube II becomes less. Conversely, the coupling between primary winding I5 and secondary winding I2 is increased and the intensity of neon tube I0 becomes greater. are in the positions shown in Fig. 1, the magnetic forces of repulsion between windings I2 and I5 are greater than those between windings I3 and I5. As mentioned heretofore, there is sufficient friction between winding I5 and winding leg I8 to prevent this difference from causing movement of winding (5 and the latter remains stationary until it is moved or manipulated mechanically by hand or some other suitable means. Similarly, in the constructions which are described hereinafter the movable regulating members are adapted to withstand the magnetic forces present.

In practice, the movement of primary winding I5 from a point adjacent secondary winding I3 to a point adjacent secondary winding I2 causes a smooth decrease of illumination intensity in the mercury vapor tube I i and a smooth increase in neon tube I Il. Fig. 2 shows a graphic illustration of the manner in which the intensity of the two tubes Varies, the iine 49 representing the intensity of the neon tube and line 5G the intensity of the mercury vapor tube. The dot and dash vertical line 5I represents the relative intensities of the two tubeswhen the primary winding I5 is in the position shown in Fig. i.

The tubes it! and II are intended to be closely associated Aso that the light given off by them is a composite, or resultant, of the light from the two tubes. Where two tubes, one of them emitting the orange red light of a neon tube, and the other the green and blue light of a mercury vapor tube having a coating of green fluorescing salts are associated together in proper proportions of illumination, the resulting light is of a white color and is satisfactory for lighting purposes. As was stated earlier in this description, when the primary winding I5 moves beyond the region in which such a white light is obtained the light will have a definite green, or orangered cast, depending upon the direction in which the primary winding has been moved. The shade of white, of course, varies as the proportion of orange-red varies within the mentioned range. It has been found that different shades are satisfactory for different purposes. With the arrangement of this invention it is possible to obtain the exact shade of light desired with great convenience. It is also possible to restore the combination to the exact shade desired if such shade has become disturbed due to intensity changes having occurred with use.

In the arrangement illustrated in Fig. 3 the transformer has only one stationary secondary winding 55. The closed or shell type magnetic core 56 has relatively elongated legs and has a pair of shunt members 51, similar to the shunt When the windings y elements described in connection with Fig. i, extending between the core legs and located adjacent the secondary winding 55. The primary Winding be is readily movable into positions at varying distances from the secondary winding 55. Gaseous vapor discharge tube be is connected in the output circuit of the secondary winding, this output circuit being somewhat different Vfrom those described in connection with Fig. i in that both terminals oi the secondary winding are connected to the terminals oi the tube by the conductors et. The primary winding is connected to a suitable source or electrical energy by means ci conductors di. In this combination, the intensity of illumination of tube bil decreases as the distance between the primary andthe secondary windings increases. It is ob vious that such an arrangement isuseiul for y varying the intensity of a single tube or oi a number oi tubes which may be connected in series with one another in the output circuit. Where it is desirable to use a combination ci more than two colors the arrangement of Fig. 3 may be combined `with that of Fig. l and the illumination intensity of all of the tubes may be varied as desired. Ii" it is desired to have each tube variablev individually, a number or combinations such as is shown in Fig. 3 may be used.

In Fig. l is illustrated a modification oi the invention in which the primary Winding lsstationary and there are two secondary windings,

one of which is stationary and the other movable. The transformer has a shell type of core ill and the windings surround the winding leg in the usual manner, stationary secondary winding ii being located at one end and stationary primary winding i2 being located in adjacent spaced relation to secondary winding il, a pair of shunt members i3 being located between them, and a second pair or shunt members it being located on the opposite side of primary winding 52. The secondary winding l5 is movable along the Winding leg into positions at varying distances from the primary winding l2. Gaseous discharge tubes l and il are connected in the output circuits of secondary windings li and l5,

In Figs. 5 and 6 is illustrated a transformer in A which the Variation in the leakage reactance is obtained by the movement or the shunt members into and out or" the air spaces between the legs of the magnetic core. The shell type core tu is of the usual construction and the secondary windings 8l and 82 and primary winding 33 are located in fixed position surrounding the winding leg, the primary winding being located between the secondary windings. Pairs oi shunt members 8@ and 85 are located between the primary winding and the secondary windings. The shunt members are 'each slidable laterally between a pair of thin members of non-magnetic material 86, this material preferably being brass. laminations of the shunts are held together by means of rivets B1, which also fasten these shunt members to a cross bar 83 which extends between them. A threaded thumb screw 89 has its end portion fastened revolvably to the midportion of the-cross bar 88. A bracket member The is mounted upon the iron straps 9i which 75 accesso that the proportion of the operating :dus which threads the secondary core portion is increased and the voltage which is impressed upon the output oi the secondary, and likewise the intensity oi the tube, are correspondingly increased. lhe` shunt members et, see Fig. 6, are fastened in a similar manner to s. cross bar b2 which is adapted to be manipulated by a thumb screw e3 which passes through a bracket member @13. In opera1 tion, the secondary windings Si and di are conL11 nected to gaseous discharge tubes dil and oi diderent colors. When it is desired-to increase the intensity or tube shunt members are drawn laterally outwardly rom'the space between the core legs. In the same way when it desired to increase the intensity or" tube shunt members are drawn outwardly. When it is desired to decrease t e intensity. oi the tubes the shunt members are moved inwardly into the spaces. The arrangement is such that the shunt members cannot be moved outwardly farther than a point beyond which an unsafe current is obtained in the output circuit. It is understood that the invention is not limited to the mechanism including the thumb screws ior moving the shunt members but any suitable mechanism may be used.

In Fig. 7 is illustrated an arrangement in which both the primary winding and 'the shunt elements are movable. The secondary windings it@ and lili are mounted over the winding leg ci the core H12 in iixed position at the ends thereof, and the primary winding M33 is mounted over the same leg and is readily slidable into position at varying distances from the secondary windings. The pairs or" shunt members itil and leb are arranged adjacent the secondary winding ibo and lill, respectively, and are movable laterally in the spaces between the core legs in the same manner as is illustrated in connection with Figs. 5 and 6, the cross bars it and itl and thumb screws m8 and it being used for moving the said shunt members. This construction possesses the advantage that it is possible to supplement the intensity variation provided by movement of the primary winding with the variation provided by movement of the shunt members.

In Fig. 8 is illustrated a transformer of the socalled core type in which there is only one' leg in addition to the Winding leg. rIhe core il@ has primary winding i il mounted slidably upon the winding leg H2, and the secondary winding H3 mounted in xed position at one end oi the Winding leg. A shunt member lll is mounted adjacentl the secondary winding i i3 in the space between theI two legs and is movable laterally in said space in the same manner described in connection with Figs. 5 andv 6, such lateral movement being imparted to it by means of thumb screw H6.l In general, this arrangement pos' sesses properties similar to that of Fig. 7.

In Fig. 9 a transformer is illustrated which does not employ shunt members. For some applications it may be desirable to omit the shunt members. lAlthough the shunt members facilitate varying the energy supplied to the output circuit, this may be accomplished without their presence, the leakage path in such case being across the air space between the core legs. The core 42B has primary winding I2l and Secondary winding l22 surrounding the winding leg thereof, these windings both being movable along the winding leg, whereby movement of either causes variation in the output of the secondary winding 22 by varying the coupling between the windings.

The mechanism described above for varying the illumination intensity of gaseous discharge tubes without impairing the steady, smooth light emission therefrom has many useful applications. Particularly in decorative sign work they may be used to impart many pleasing color change effects. While the movable parts are shown as being adapted to be moved by hand, it is obvious that they may also be moved by an electric motor under the control of a hand switch, the motor being adapted to move the member in either direction as desired. Mechanism may be incorporated for maving the movable members continuously to provide a continual color change, or intermittently at desired intervals. Such mechanism, driven by electric motors, may be readily applied to the regulating means of this invention. It may be applied to the shunt members as well as the movable winding.

While the invention is directed primarily to the regulation of the illumination intensity of gaseous discharge tubes, and possesses particular advantages for, such use, as has been explained heretofore, in its broad aspects it provides means for regulating the supply of electrical energy to l a load circuit by regulating the transfer of energy from a primary winding to a. secondary winding and is of general application where such regulation is desired.

I claim:

1. In combination, a discharge lamp and a transformer, said transformer comprising a substantially closed magnetic core having a relatively long winding leg and at least one-other relatively long leg, primary and secondary windings surrounding diiferent portions of said winding leg, and fixed magnetic shunt members located between said primary and secondary windings and extending between said winding leg and said other leg, at least one of said windings being movable along said winding leg into positions at varying distances from the other of said Windings, said secondary Winding being electrically connected to said discharge lamp.

2. In combination, two discharge lamps and a transformer, said transformer comprising a magnetic core having a winding leg, two secondary windings surrounding different portions of said winding leg, and a primary winding surrounding said winding leg and located between said secondary windings, magnetic shunt members between said primary and each of said secondary windings, at least one of said windings being movable along said winding leg into Varying D- sitions, said secondary windings being electrically connected to said discharge lamps respectively.

3. In combination, two discharge tubes, and a transformer, said transformer comprising a closed magneti-c circuit core having a winding leg, two secondary windings surrounding said `winding leg and located at fixed, spaced-apart ondary windings, said secondari7 windings being,

electrically connected to said gaseous discharge tubes, respectively.

fl. In a composite lighting unit composed of two differently colored light sources and a source of electrical energy therefor, means for regulating the color of the light from said composite lighting unit comprising a transformer comprising a magnetic core having a winding leg, two secondary windings .mounted in xed, spaced-apart positions surrounding said winding leg, and a primary winding surrounding said winding leg and located between said secondary windings and movable along said winding leg into varying positions between said secondary windings, said secondary windings being electrically connected to said differently colored light sources respectively, and said primary winding being connected to said energy source.

5. In a composite lighting unit composed of two differently colored light sourcesl and an electrical energy supply circuit therefor, means in said supply circuit for regulating the color of the light from said composite lighting unit comprising a transformer comprising a magnetic core having a winding leg, a primary winding and a secondary Winding mounted in fixed adjacent positions surrounding said winding leg, and a vsecond secondary winding surrounding said winding leg and located on the opposite side of said primary Winding from said first secondary winding, magnetic shunt members between said primary winding and each of said secondary windings, said second secondary winding being movable along said winding leg into positions at varying distances from said primary winding, said secondary windings being electrically connected to said differently colored light sources respectively.

6. In combination, va discharge tube and a transformer in the input of said tube, said transformer ,comprising a magnetic core having a windingI leg, primary and secondary windings Vsurrounding said winding leg, and a magnetic shunt between said primary and secondary Lwindings, said shunt providing a iiux leakage path for said transformer, one of said windings being movable-along said winding leg into positions at varying distances from` the other of said windings, and said shunt being movable to vary the magnetic reluctance of said flux leakage path.

PAUL BERGER.