US2436742A - Line cord transformer - Google Patents

Description

Feb. 24, 1948. w. H. BUSSEY LINE CORD TRANSFORMER Filed Sept. 15, 1945 g m i m g g W E Q 2 gm 2 Am,

Patented Feb. 24, 1948 LINE CORD TRANSFORMER William H; Bussey, Chicago, IlL, assignor, by mesne assignments, to Robert L. Kahn, trustee Application. September 13, 19.45, Serial No. 615,989

4' Claims. (01. 175356) 1 This invention relates to an electrical apparatus and particularly to a combined transformer and line cord. In certain low power types of apparatus energized from the customary alternatmay be of any suitable gauge and preferably should be fine enough so that flexibility of the cord is assured. The wire itself should be of suitable material for use in the transformer and ing current supply circuit, it is desirable to obpreferably is of soft iron having a high degree tain either electrical isolation from the supply of flexibility. The individual strands of wire circuit or a voltage change or both. Thus, with may be insulated from each other to reduce eddy fluorescent type of lights on the market, it is decurrents in any manner well known in the art. sirable to provide a high starting voltage of the Thus, the wires may have a fine coating of enorder of 180 and reduce this to around 75 for amel or other flexible film, or reliance may be normal operation. had upon the oxide coating for insulation. Thus A1 1 power lectric lamps which may be as an example, I have successfully used a bundle used in various ways may advantageously be of number 26 wire, which bundle had a diameter operated from 110 volt lines. Such lamps are of oneourth inchmade to operate at low voltage of the order of 1:, I m diat y ou d core it is insulation H in one or more volts and operate from small dry any form whatsoever, here shown as a spiral of cells. To operate such lamps from a 110 volt thin flexible material. Thus, a ribbon of paper supply circuit requires either a transformer or or any of the various tapes on the market may a resistance. be provided. Varnish or other film forming in Low voltages are necessary for door bells, buz- 2 sulation may be u zers and annunciators. Transformers for these Around insulation C l -p W l2 s w purposes are commonly used and require special Wire l2 y have any desired gauge Suitable connections. for the purpose desired and, if heavy current In addition to the above fields of use, small rryin cap ity is n c ry. wi I m y be portable radio receivers operating from alter- Stranded o y be formed of a fiat ribbon. nating current supply circuits require different Looking from the l o Figure 1 Wn a on voltages for energizing the cathodes of vacuum Wire C layer 52 of 101 W y be tubes and also energizing the plate circuits. As a Wound around in the direction corresponding t rule, the transformer in such a device is bulky o r g t-hand screw thread. Above layer I2 is and constitutes a heavy space consuming item, copp W e l ye It Wound W a pitch pp e In accordance with the invention herein, there o y r s t t this w ld e ac rd n t a is provided a transformer fashioned to constitute left-hand screw thread. In order to have the two a line cord. The transformer li d may b terminals of one transformer winding terminate manufactured in continuous lengths and cut to at the s end of the 00rd. it is advisable to use. A transformer embodying this invention 3 vide a winding into tw r any v number has highly desirable characteristics. Thus, the 0f layers- Thus, layers 52 and y f m o e transformer has poor voltage regulation so that Windingshort eircuiting the transformer secondary will Above Winding 4 y be insulating yer it of not blow ordinary house fuses or damage any ap nv h or y t e mat rial. Above Wiring. Any desired numb of windings may layer 16 are successive layers 13 and f9 wound be provided on the transformer and complete elec- With Opposing pitch, these two b g f any suit trical isolation from the house supply circuit is able wire and forming the t p ti s of anassured. By providing connectors at th d other winding. Additional windings may be added of the transformer line cord, inconvenient bulky if desired, and e outside o the 00rd y he transformers within any article such as radio covered with a layer of any material such as receiver may be eliminated. A transformer in rubber or tubular knitted C tton y other the form of a line cord has the further advantage material u s h ou r v ri f c v nof having a high ratio of surface to mass so that tional line cords. heat dissipation is efficient. In the manufacture of such cord, core lo may For a more thorough understanding of the inbe fed continuously with the various layers being vention, reference will now be made to the drawwound around. Ihus, annularly moving spools ings wherein Figure 1 shows a view of a transwhirlin around a long central core to wind a former line cord in the process of manufacture. layer of wir thr p r other m l re Figure 2 is a section on line 22. Figure 3 shows H well known in the winding art. By feeding wire a length of transformer line cord with parts broi9 forward in the direction of the arrow, namely ken away but provided with plugs and connected from left to right and having the different layfor use. ers fed in the order shown in Figure l, the entire Referring first to Figures 1 and 2, the magnetic transformer core may be manufactured in incore of the transformer line cord comprises bundefinite lengths. Thus, the supply of insulation dle ID of flexible magnetizable wire. The wire 69 H will go on core l0 first, followed in succession prevent breakage and unravelling of wire.

by the various other layers. The places where winding of the various layers occur are staggered along the length of core Ill.

It is evident that adjacent spools containing the material for forming the various layers will turn in opposing directions. Thus, spool II for tape I I may revolve clockwise around core looking at the core from left to right. Spool [2 for feeding layer [2 will therefore revolve anti-clockwise. Spools l i', I6, I8 and [9' will follow successively.

In Figure 3, a length of cord is shown. It is assumed that this length has been wound with all the various layers. Thus, end 23 of iron wire It may be anchored in a suitable connector 25. The ends of windings l2 and M, for example, may be formed as leads 2'! and '28 and provided with suitable terminals. Windings l2 and I4 have ends 29 and 311 remote from connector 25, which ends are electrically connected together at 3|. It is understood that these ends and joint 3| are suitably insulated and tied down to the cord proper. Thus, these two layers form one transformer winding.

Similarly, layers iii and 19 have leads 32 and 33 respectively going to connector 25. This connector is shown as the standard type for use in 110 volt lines. Remote ends 3d and 35 of these windings are connected together at 36 to form a through circuit for layers l8 and [9. The finished cord would have tape or other finishing 1naterial around the ends of the cord adjacent the two connectors to provide a finished material and It is not necessary that adjacent windings be used to form a winding. Thus, layer 12 and layer l9 could form a complete winding. Any even number of layers may be connected together so that the two leads are at the same end of the cord providing the pitch is such as to have magnetically additive action. A connector plug for ends 27 and 28 may be provided in which case the end of core Hi would be anchored.

If additional windings are provided, leads to other terminals may be made at one or both ends. Separable connectors accommodating any desired number of wires are well known. Hence, additional leads from windings may be provided at either end of the cord and led to suitable terminals to connectors if desired.

It is, of course, possible to have one transformer winding consisting, for example, of layers l2 and i as shown, and have layer It as one complete winding and layer I9 as another complete winding. It is also possible to break any layer into two separate windings. Thus, a cord six feet long may have a primary winding consisting of layers l2 and M. The third and fourth wire layers, here numbered as It and I9, may then be connected for a portion of the length, say four feet of cord, while another winding electrically separate from 18 and 19 but consisting of the third and fourth layers of wire may be provided. Thus, different windings may be provided along the same layers of wire along a length of cord.

As shown here, the outer layers are the primary. This is unimportant. For some purposes, it may be desirable to have the primary on the inside. It is evident that the core and windings have a length which, is great in comparison to the transverse dimension of the transformer cord.

It is obvious that, instead of transformers, reactors and autotransformers may be made without departing from the spirit of the invention.

What is claimed is:

1. A transformer comprising a magnetizable core in flexible filamentary form, windings helically disposed around said core and having superposed layers with adjacent layers of opposing pitch, said windings and core having an axial length great in comparison to the maximum transverse dimension, said core and windings being flexible and forming a line cord, and primary and secondary connections at the ends of said windings.

2. A transformer comprising an elongated bundle of flexible magnetizable wire, a plurality of windings helically disposed around said bundle to form therewith a flexible cord-like structure, said windings having superposed layers with opposing pitch, a connector at one end of said bundle and anchored thereto, said connector having terminals to which the ends of one of the windings may be connected, and terminals for other windings at the other end of said bundle.

3. A transformer comprising a long thin bundle of flexible magnetizable wire, a plurality of layers of wire helically wound around said wire along the length thereof to form windings and having superposed layers with adjacent layers of opposing pitch, said bundle and windings forming a flexible cord-like structure having a length great in comparison to any transverse dimension, at least one connector anchored to one end of said magnetizable wire, said connector having ter minals to which one of the windings is connected for establishing circuit connections, and terminals for the remaining windings at the other end of said magnetizable wire.

4. A transformer comprising a long bundle of magnetizable wire, an even number of four or more superposed wire layers wound around said bundle, at least two wire layers being Wound with opposing pitch, the ends of two layers at one end of said bundle forming leads for connection to a circuit, the remaining ends of said two layers of wire at the other end of said bundle being an electrically continuous winding, said layers being magnetically aiding, the remaining layers being similarly connected to form continuous electrical windings, said bundle and windings forming a long flexible cord, leads for one winding at one end of the bundle and leads for the remaining windings at the other end of the bundle whereby said transformer may be used as a line cord between a power source and a load.

WILLIAM H. BUSSEY.

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

UNITED STATES PATENTS Number Name I Date 400,795 Root Apr. 2, 1889 447,569 Kennedy Mar. 3, 1891 1,208,938 Finch Dec. 19, 1916, 1,722,362 Wiley July 30, 1929 2,251,898 Sittler Aug. 5, 1941 FOREIGN PATENTS Number Country Date 1,212 Great Britain May 4, 1885

Images