US501859A - Method of preparing cables for multiple switchboards - Google Patents

Description

UNITED STATES PATENT OFFICE.

ORO A. BELL, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE WESTERN ELECTRIC COMPANY, OF CHICAGO, ILLINOIS.

METHOD OF PREPARING CABLES FOR'MULTIPLE SWITCHBOARDS.

SPECIFICATION forming part of Letters Patent No. 501,859, dated July 18, 1893.

Application iiled`November'7,1892. Serial No. 451,251. (No model.)

To @ZZ whom it may con/cern.:

Be it known that I, OROA. BELL, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented a certain new and useful Improvement in the Manufacture of Cables for Multiple Switchboards, (Case No. 6,) of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specication.

My invention relates -to wiring multiple switch boards, and more particularly to wiring by means of separate pieces of cable.

The objects of my invention are, tirst, to prevent the loss of material in the formation of separate cables necessitated by previous methods; and, second, to lessen the labor required in the formation of the cables.

My invention consists in removing the outside serving from a portion of a cable, laying aside the mass of conductors thus exposed, takingup the wires individually and passing them around proper pins, binding the wires together so that they may retain their positions when removed from the forms, and severing the conducting wires; whereby the ends of two separate cables are at the same time and by one operation properly formed for attachment to the spring jack switches.

A multiple switch board is provided with several duplicate sections, each section being composed of strips of spring jack switches, each strip containing usually twenty switches.

The corresponding springV j ac ks upon the dif-V ferent sections are connected together by conducting wires and itis usual to collect all of the conducting wires belonging to the spring jacks of corresponding strips into a single cable. The cables thus formed are placed at the back of the board, and in wiring by separate cables the corresponding strips of spring jacks upon adjacent sections are connected by short cables which are designated as separate cables. These separate cables or pieces of cable for a single series of strips are thus formed into a continuous cable placed back of the board. The conducting wires in each piece of cable leave the piece when opposite the spring jack to which they are attached so that the extremities of each will present the appearance of wires projecting from the body of the piece at equidistant points along said extremities. Thus at each end for a distance equal to the length of a strip of spring jacks the conducting wires successively leave the body of the piece and pass directly to the terminals of the spring jacks. It will be seen that two adjacent pieces when placed in position will overlap at their ends throughout those portions that are opposite the strips of spring jacks to which their wires are connected or, in other words, will overlap throughout those portions of their extremities from which the conducting wires project. These overlapping ends are either bound together or left free to suit the particular requirements.

In multiple switch boards as now constructed, there are usually three conducting wires passing from a spring jack upon one section to a corresponding spring jack upon the next section so thatinstead of one wire leaving the body of the cable opposite a spring jack there will be three, and each piece of cable will contain sixty wires. Previous to my invention these pieces of cable have been formed principally in two ways. By the rst method the piece is formed directly from single wires which are placed around pins so that each wire may occupy its proper position, the wires being then bound together so that they may retain their relative positions when removed 'from the pins.

A second method has been to take a cable of proper length,jremove the serving from the ends throughout a proper distance, take up individually the insulated `wires and place them around pins an'dbind them together in this position. The former of these methods requires a great deal of labor, and the latter though'requiring less labor than the first is accompanied by an unavoidable waste of material, for the wire that projects from the body of the piece at its extreme end determines the length of cable that must be used, and as all other wires project from the piece a greater distance than the extreme wire, the ends of all must be cut away so that they may correspond in length to the length of the extreme wire.

To facilitate the formation of the piece by my method, the wires belonging to the same line are bound together in strands o r groups and each wire is provided with a different color, as in the insulation.

My method will be more readily understood by reference to the accompanying drawings, in which- Figure l is an yelevation of one of the duplicate forms upon which the wires are placed in the formation of the ends of the cables. Fig. 2 is an end view thereof. Fig. 3 is adiagram illustrating the manner in which the individual wires are placed around the pins, one wire being shown as placed around each pair of pins.

Like letters refer to like parts in the several gures.

A plate a is provided upon one side with a ange a2 by means of which it may be secured in position. To the face of the plate a opposite to that carrying the flange is fastened a block b, preferably of wood, by means of screws d d. The plate a also carries at its upper edge a series of equidistant pins a" a', each pin bending at right angles to extend over the block b, thus forming a receptacle for the wires between the block b and the bent portions a3 of the pins. The block b is cut away at points between the fingers a a to permit of the free passage of the binding thread between the wires of the cable and the block b. Two such forms are placed parallel, with the portions a3 of the pins extending outward, and at such a distance apart that the distance between the pins may be twice the required length of the wires that are to project from the body of the piece. The outer serving having been removed from a cable throughout the necessary distance and at the proper point, a wire, determined by the color of the insulation, is taken from the mass thus laid bare and placed around the pins marked No. l upon each form, these pins lying directly opposite. A second Wire is placed around pins No.2, and so on with all the wires of the cable, the proper position of each wire being determined by the color of its insulation.

In Fig. 3 the cable is shown as containing twenty wires, one wire passing around each pair of pins. In wiring multiple switch boards, as before stated, there will be usually three wires passing to each spring jack. These three wires are passed around the same pins. I have found it desirable to form the two conductors constituting the metallic circuit of each line into a single strand by wrapping them with thread before placing them in the cable. I prefer to leave the test wire free. Thus there will be a strand and a single wire to'be placed around each pair of pins. All of the wires having been thus placed around the proper pins, the wires-lying in the receptacle of the forms are bound together by threadl in such a manner that each wire may maintain its position when removed from the forms. I preferably accomplish this by spirally winding thread or twine m m around the conductors in such a manner that the twine may bear against each wire where it leaves the body of the cable. The wires having been thus bound together the parallel portions of the wires running from one form to the other are cut upon a line a a and the pieces are removed from the forms. In this manner, the ends of two separate pieces are formed at the same time without waste of material.

To assist the eye and the memory in the selection of the proper wire for each pin I have found it convenient to place a chart in proximity to the forms, the chart being provided, at points opposite each pin, with col ors corresponding to those of the Wires that are to be placed around the respective pinsA Having thus described my invention, I claim as new and desire `to secure by Letters Patent- 1. The method of preparing cable connections, which consists in removing the serving from a portion of a cable, separating the ex posed portion into two parts connected by wires leaving said parts at different points, and

severingthe connecting Wires midwaybetween said parts; whereby two pieces of cable are formed with wires of equal length projecting at different points along the extremities thereof, substantially as described.

2. The method of preparing cable connections, which consists in removing the serving from a portion of a cable, separating the exposed portion into two parallel parts connected bywires passing from points along one of said parts to points along the other, and severing said connecting wires; whereby two separate cables are formed with wires of equal length projecting at different points along the extremities thereof, substantially as described.

3. The method, which consists in removing the serving from a portion of a cable, separating the exposed wires into two groups connected by wires leaving said groupseach at a different distance from the end thereof and in uniform order, binding together the groups thus formed by passing a thread around the groups where the wires leave the same, and severing the connecting wires; whereby two separate cables are formed with wires of equal length projecting at different points along the extremities thereof, substantially as described.

et. The method of arranging the wires of cables for connecting therewith, which consists in laying bare a portion of the cable, bending aside the said bared portion to shorten the same, separating the different wires of the cable from the mass thereof at IOO dierent points along the bared `portion, and In witness whereofl hereunto subscribe my severing Y the Wires atY equal distances from name this 13th day of October, A. D. 1892. the axis of the cable; whereby two separate cables are formed, each having its wires pro- 5 truding from its mass to equal distances at Witnesses:

different points along its length, substantially Y MILLS H. LANDON, as described. .Y Y. A. L. PALTZ.

ORO A. BELL.

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