US1570921A - Electrical transformer - Google Patents

Description

Jam 26 1,570,92E

E. a. PATTERSON ELECTRI CAL IRANS FORMER Filed April 14, 1925 ii atented Jan, 26, 1926,

EDWARD B'. PATTERSON, OF MERCHANTVILLE, NEW JERSEY.

nnnernroan TRANSFORMER.

Application filed April 14, 1925. Serial No. 22,934.

To 077 whom it may concern:

Be it known that I, EDWARD B. PATTER- SON, a citizen of the United States, residing at Mcrchantvillc, in the county of Camden and State of New Jersey, have invented a certain new and useful Improvement in Electrical Transformers, whereof the following is a specification, reference being had to the accompanying drawing.

My improvement is particularly designed and adapted for embodiment in. apparatus for amplification of short wave or high frequency electric radiant energy such as is characteristic of radio broadcasting. Serious difficulty is encountered in attempting to employ the usual design of radio frequency transformers, in that tuning of the secondary coil is accompanied by noticeable tuning of the primary coil which is usually manifested by oscillationof the radio frequency thermionic tube, due to the plate electrode of the latter being tuned. In other words; placing the primary and secondary coils of such an ordinary transformer in such relation as to produce the desired induction in the secondary coil from the energy in the primary coil, causes a reaction or counterinductance from the secondary coil to the primary coil which is manifest in distortion of the wave form of the energy being received, which distortion is, of course, further manifested in slurring the sounds produced by the incoming energy when reducedto audio frequency; with consequent reduction in the efiicieney of the receiving apparatus as a whole.

Therefore, an object and effect of my inv'cntion is to permit the placement of primarv and secondary coils in such coupled relation as to effect the desired maximum induction in the secondary coil from the primary coil while eliminating or minimizing, to a negligible condition, the counter-effect of Ethe secondary coil upon the primary coil abo contemplated.

As hereinafter described, my invention ineludes the combination with a cylindrically helically coiled primary electrical conductor; of a conically helically coiled secondary electrical conductor, in such relation with said primary coil that the major portion of the lines of force in the magnetic field produced by electrically energizing said primary coil interlink with said secondary coil; but only a negligible minor portion of the lines of force in the magnetic field of said secondary coil interlink with said primary coil.

My invention includes the various novel features of construction and arrangement hereinafter more definitely specified.

In Fig. I of said drawing I have diagrammatically indicated a primary and a secondary coil with the lines of force of each disposed in accordance with the recognized laws governing the same.

Fig. H is a side elevation of such a transformer.

The primary coil 1 is conveniently formed of a cylindrically helically wound electric conductor. The secondary coil 2 is conveniently formed of a conically helically wounl electric conductor disposed in coaxial telescopic relation with said primary coil, as indicated by the dotted lines extending from the right hand side of said coil 1 in Fig. 1. The relative position of said coils 1 and 2 is such that the major portion of the lines of force 4 in the magnetic field produced by electrically energizing said primary coil linterlink with the convolutions of said secondary coil 2; whereas, only a minor portion of the lines of force 6 in the magnetic field of said secondary coil 2 interlink with said primary coil; the major portion only being illustrated extending in such directions as to avoid the convolutions of said primary coil 1. In the construction and arrangement indicated in said drawing; the maximum inductive efiect of said primary coil upon said secondary coil is at tained, while the counter-inductive effect of said secondary coil upon said primary coil is rendered negligible.

it prefer to provide said 'coils with such connecting appurtenances that the relative position of said coils may be adjustably varied and they may be supported, as a transformer unit, in detachable relation with a base or wall panel of a frame or cabinet supporting the radio receiving apparatus of which such transformer is a component. Such mounting members may be conveniently formed of insulating material. For instance, as shown in Fig. H'the primary coil 1 may be wound upon a cylindrical tube of celluloid or vulcanized fibre 8 and the secondary coil 2 may be wound upon a conical form 9 of such insulating material or be interlaced with strips 10 of insulating mate rial extending radially from the apex to the base of its conical configuration, and such suppol ts of said secondary coil may be in contact with the support 12 of the primary coil or be connected therewith by primarily separate insulating supports 13 and 14 preferably provided with screw means15 for detachable connection with a horizontal or a vertical panel of the apparatus frame or cabinet.

As indicated by the dotted lines in Fig. I; said coils 1 and 2 are relatively telescopically adjustable to vary the extent of interlinking of their respective fields 4 and 6. Such movement is conveniently effected by sliding said coils upon the support 12 shown in Fig. II; the su porting elements 8 and 13 being frictionally engaged with said support 12.

However, I do not desire to limit myselt to the precise details of construction and arrangement herein set forth, as it is obvious that various modifications may be made therein without departing from the essential features of my invention, as defined in the appended claims.

I claim:

1. In an electrical transformer; the combination with a cylindrically helically coiled primary electrical conductor; of a conically ielically coiled secondary electrical conductor, in coaxial telescopic relation therewith; said primary coil being adjacent the larger end of the secondary coil and the relative position of said coils being such that the major portion of the lines of force in the magnetic field produced by electrically energizing said primary coil interlink with the convolutions of said secondary coil, but only a negligible minor portion of the lines of force in the magnetic field thus induced in said secondary co l interlink with said primary coil; whereb the maximum inductive effect of said primary coil upon said secondary coil is attained but the counter-inductive effect of said secondary coil upon said primary coil is minimized.

2. In an electrical transformer; the combination with a cylindrically coiled primary electrical conductor; of a conioally coiled secondary electrical conductor, in inductively coupled relation therewith; said primary coil being adjacent the larger end of the secondary coil and the relative position of said coils being such that the major portion of the lines or force in the magnetic field produced by electrically energizing said primary coil affect said secondary coil, but only a negligible minor portion of the lines of force in the magnetic field thus induced in said secondary coil afi'ect said primary coil.

8. In an electrical transformer; the combination with a cylindrical primary coil; of a conical secondary coil, in coaxial telescopic electrically coupled relation therewith; said primary coil being adjacent the larger end of said secondary coil.

4. In an electrfcal transformer; the combination with a cylindrical primary coil; of

a conical secondary coil, in electrically coupled relation therewith; said primary coil being adjacent the larger end of said secondary coil.

In testimony whereof, I have hereunto signed my name at Philadelphia, Pennsylvania, this thirteenth day of April, 1925.

EDWARD B. PATTERSON.

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