US1491343A

US1491343A - Loading coil

Info

Publication number: US1491343A
Application number: US471316A
Authority: US
Inventors: Fondiller William
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1921-05-21
Filing date: 1921-05-21
Publication date: 1924-04-22
Anticipated expiration: 1941-04-22

Description

Avril l 1924:

W` FONDILLER LQADING COIL Filed May 2l 1921 h. N QN Twmwm BMN Rh Amc N s @www Patented Apr. 22, 1924.

narran` llUallES PATENT f FMQE,

WILLIAM FONDILLER, O'F NEW YORK, N. Y., ASSIGNOR TO WESTERN ELECTRIC COM- P'NY, INCORPORATED, 0F NEW YORK,

N. Y., A CORPORATION OF NEW' YORK.

LOADNG COEL.

Application filed May 21,

T0 al?, fic/2,0m t may con-cern.'

Be it known that l, lNi'LLrAM FoNmLLnn, a citizen ot the United States, residing at New York city, in the county of New York, State of New liiorlr7 have invented certain new and useful improvements in Loading Coils, of which the toll-turing is a full, clear, concise, and erect description.

This invention relates to inductance devices and more particularly it relates to a unitary loading device for a duplex circuit.

As is well known in the art, it is frequently desirable to add inductance units at one or more points to a signaling line in order to improve its transmission characteristics.

An object of this invention is to provide a unitary inductance device which may be inserted in a duplex circuit for simultaneously loading the two physical circuits and the derived phantom circuit whereby the use of an inductance device for each oit these circuits is rendered unnecessary.

One form of the inductance device this invention may have, comprises four parallel members with a cross at each end ot the parallel members for oining them. The inductance for each wire of each physical circuit comprises a winding on one of the parallel members and may also comprise supplementary windings on arms of the crosses, which supplementary windings may be included in each side circuit in such a manner that the ratio between the physical and phantom loading may be made any desired value.

This typeot kinductance device possesses advantages over the toroidal type of loading coil in that the loading coil or this invention comprises only straight portions which may be readily wound without the necessity of providing special and expensive machinery. lt is preferable that the magnetic means joining the units of the four parallel members should each bein the form of a cross, since it has been found that such an arrangement tends to eliminate more completely cross talk between the side circuits and the phantom circuit of the three talking circuits loaded by the device, than it is possible to obtain from magnetic joining means of other types, such as a toroid or a rectangular frame.

r1`his invention will be better understood by reference to the following detailed de- 1921. Serial No. 471,316.

scription, taken in connection with the accompanying drawings in which Fig. 1 represents an inductance device according to this invention, arranged to load two physical circuits and the derived phantom circuit, in which non-magnetic gaps are provided in the cross members of the core for increasing the ratio of phantom to side circuit loading7 and Fig. 2 represents a modification of Fig. 1 in which the ratio of phantom to side circuit loading may be adjusted by varying the number of turns of the supplementary windings located on the `cross members.

Fig. 1 discloses two two-wire

circuits comprising line'conductors

10 and 11, and 12 and 13, respectively. 14 and 15 are signaling devices which may be employed for transmitting signals such as telephone currents over line conductors 10 and 11 while the signaling devices 16 and 17 are arranged to signal over

line conductors

12 and 13. The signaling devices 18 and 19, by connections well known in the art, are ar ranged for signaling over the phantom circuit derived by employing line conductors 10 and 11 in parallel for transmission of the signaling currents in one direction and

line conductors

12 and 13 in parallel for the transmission of the signaling currents in the opposite direction.

The inductance device disclosed in Fig. 1 tor simultaneously loading the physical circuits and the derived phantom circuit comprises tour parallel members 20, 21, 2:2 and i QS which are at one end joined by a cross comprising the four arms 24, 25, 26 and 2? and are joined at `the other end by a cross comprising the four

arms

28, 29, SO and 31. Line conductor 1() is loaded by the main inductance winding 32 on core member Q1 and by the two supplementary windings and 34 on the cross arms 8O and 26. Line conductor 11 is loaded by the main inductance winding on core member 22 and by the supplementary windings 36 and 37 located on the cross arms 29 and 25. Similarly line conductor 12 is loaded by the main inductance winding 38 and supplementary windings 39 and 420; and line conductor 13 is loaded by main inductance winding l1 and the supplementary windings 412 and 43.

It' we assume that the instantaneous physical current in the twov side circuits is in the direction of the full arrows adjacent the line conductors, the direction of the flux produced in the core members is shown by the full line arrows on each core member. Similarly, instantaneous current in the phantom circuit in the direction indicated by the dotted arrowsJ will produce a flux in the loading coil in a direction indicated by the dotted arrows on the core members. As shown by these arrows, the ilux for side circuit 10, 11 starting tor example in .core member A:a3 passes through arms and 24, parallel member 20,\

cross arms

28 and 31, back to parallel member 23, and the directions of the flux for the'two'main windings and the four supplementary windings are all in the same direction. Similarly, the flux for the

side Circuit

12, 13, starting for example in parallel member 22 traverses cross arms 26 and 25, parallel member 21y cross arms 29 and 30, back to parallel member 22; and the directions of the Hur: iiorthe two main. windings and the four supplementary windings surrounding the described rectangle are all in the same direction. A portion of 'the phan- 'tom circuit flux 'traverses parallel member 23 of

side circuit

12, 13, cross. arms 27 and 25, parallel member 21 of side circuit 10, 11,

cross arms

29 and 31, back to parallel member 23; and another portion of the phantom circuit iiuX traverses core member 20 of

side circuit

12, 13, cross arms 24, 26, parallel member 22 of iside, circuit 10, 11, cross arms 30 and 287 back to parallel member 20. lf desired,non-magnetic gaps 45 and 46 may be provided in the cross arms arranged in such a manner as to oder high reluctance to the side circuitfluX and but little reluctance to the phantom circuit flux. These nonmagnetic gapsA Vas is well known in the art and as described and claimed in my Patent No.1,253,365 of January 15, 1918, serve to increase the ratio of phantom to side circuit loading, this ratio increasing with an increase in the width ofn thenon-magnetic gap. inasmuch as the iiuXes of the supplementary windings are arranged in this figure to aid the main windings for side circuit currents and oppose tor phantom circuit currents, it follows that after the ratio of side to phantom loading has been determined roughly by the width of the non-magnetic gaps for given main and supplementary windings,-tlie number of turns of the supplementary windings may be varied to accurately determine this ratio. From the above description of the direction of the flux in each of the main windings and the supplementary windings, it will be evident to those skilled in the art that the flux for each of the three talking circuits is arranged in such a manner that cross talk therebetween is minimized.

Fig. 2, discloses a modification oi Fig. 1 in which the ratio of phantom to side circuit loading `may be increased to any desired lfor phantom currents but oppose them for side circuit currents. lt is therefore evident that inereasingthe number of turns o'f the supplementary windings with regard to its main inductance winding will increase the ratio vof phantom to side circuit loading while decreasing the number of turns of the supplementary windings will decrease ythis ratio. inasmuch as Fig. 2, `is similar to Fig. 1y except that the non-magnetic gaps 45 and 46 have been omitted, and the direction of the winding of each of the supplementary windings has been reversed in each case, it is not believed necessary to describe F ig. 2in detail. Corresponding parts of the two figures have therefore been given similar reference numerals except that the numerals for Fig. 2 are designated -as 10 11', etc.

It is to be understood that this invention is not limited to the use of windings on both the parallel members and theV crossarms, since Athe windings on either the parallel members or the cross arms, may be omitted, if desired, It is also to be understood that the structure described above may be variously modified without departing in 'any wise from the spiritV of this invention, as defined in the appended claims.

l/Vhat is claimed is:

1. An inductance Vdevice having a core comprising twoco-a-Xial rectangular frames at right angles to each other, the longitudinal sides of said rectangles being separable from the radial sides andan inductance winding on each side of each rectangle.

2. An inductance device having acore composed of two crosses, four separable arms joining the ends of said crosses, and windings placed on a plurality of the sides of said core. Y 1 [f 3. A loading coil for a plurality of physical circuits and a derived phantom circuit comprising a core comprising four parallel members and a cross at each end of said members, each ofl said crosses having an arm resting on the end ol onel of said members and a winding on each of said members for one of said physical circuits;

4. A loading coil for a plurality of physical circuits and a derived phantom circuit comprising a core comprising a plurality of parallel members, and means at eachend of said members for joining saidvmembers, a winding on each of said parallel members for one of. said circuits, and a plurality of windings on said means, one of said windings on one of said meansbeing connected to one of said windings on one of said parallel members. u F

VA loading coil for two physical twowire circuits and the derived phantom circuit having a core comprising four parallel members, a cross at each end of said members for joining said members, a main wnding on each of said parallel members for one of said wires, and a supplementary winding i on each arm of each cross.

6. A loading coil for two physical circuits and th'e derived phantom circuit having a core comprising four parallel members,y a cross at each end of said members for lioining said members, a main winding on each of said parallel members for one of the wires of said circuits, and a supplementary winding on each arm of one of said crosses for one of the wires of said circuits,the main winding on each. parallel member being directly connected to a supplementary winding on an arm. of said cross adjacent another of said parallel members.

7. A loading coil for two physical circuits and the derived phantom circuit having a core comprising four parallel members, a cross at each end of said members for joining said members, a main winding on each of said parallel members for one of the wires of said circuits, and a supplementary winding on each arm of one of said crosses for one of the wires of said circuits, the main winding on each parallel member being directly connected to a supplementary winding on an arm of said eross adjacent another of said parallel members, said supplementary windings being wound in such a direction as to aid the main windings for phantom circuit currents opposing said main windings for side circuit currents.

ln witness whereof, l hereunto subscribe my name this l9th day oi Nay, A. D. 1921.

WLLIAM FQNDILLER.