US 2106048 A
Description (OCR text may contain errors)
Jan. 18, 1938. A. T. CANDY, JR
CoDED WIRE Filed NOV. 12, 1932 2 Sheets-Shea?l l Jan. 18, 1938. A, T, CANDY, JR 2,106,048
CODED WIRE Filed NOV. 12, 1932 2 Sheets-Sheet 2 Patente .iam 19 il N ` OFF @ODE Aibert '.l. Candy, Jr., @ak liarli, lil., assigner to Candy da Company, poration of Iliinois Enc., Chicago, iii., a. cor- Application November 12, 1932, Serial No.. 642,378
My invention relates to coded Wire, many of its aspects constituting an improvement upon my application Serial No. 593,370., filed February 16, 1932, now issued as Patent No. 1,891,501 of December 20, 1932.
One object of my invention is to provide a series of wires for code work or the like wherein the different colors used may be confined to only a few readily distinguished colors but still provide for a large number of readily distinguished wires. I solve this problem preferably by the use of two color coatings-an under coating and an outer coating of different colors and in different combinations. The under coating may normally be entirely covered by the outer coating, in which case, to identify a given wire, the workman may scrape off a small spot of the outer coating to reveal the color of the under coating. If eight different colors are employed, this gives a total of sixty-four different combinations. If a third color coat is used giving combinations of three colors, the total number of distinguishable Wires in the series is increased to some five-hundred.
I prefer to employ color coatings of a waxlike material which is opaque but a very thin film.V This permits the scraping away of the outermost coat to reveal the color of the under coat without perceptibly lessening the effectiveness of the insulation or weatherproofing. Many prior attempts to code wire by color have had the objection that the effectiveness of the insulating and Weatherproong had to be greatly impaired in order to determine the identity of the Wire. While this was not particularly objectionable at the ends of a cable, it was highly objectionable in identifying a wire at some mid point of a cable where it was proposed to tap into the circuit of the wire. To cut into the weatherprooilng or insulation Yof a wire to determine its identity only to discover it was not the desired Wire, left the wire in a defective condition.
Another advantage of my wire coating is that it permits a wire warehouse to fill special orders for the more complex color-combinations by putting an additional coating on wire already made up and in stock. Thus a request for small quantities of red over blue, yellow over blue and black over blue could readily be filled by taking blue 0 coatedwire from stock and running it through' applicators to apply the necessary outer coating. Methods of coding heretofore in use have required that the wire be built initially to the ultimate requirements. of my invention therefore is the adaptability of A valuable advantage (ci. 17a-264i the system, the speed with which special orders may be turned out, the freeing of factory production from interruption by small special orders, and the reduction in stocks which need be carried on hand to provide prompt delivery on the less common requirements.
Another feature of 4my invention is the improved method and apparatus for coating wire, which is peculiarly Well adapted for the coating system of my invention.
Another feature of my invention is a coded wire and the method and apparatus for coating it, wherein the wire instead of being` given an all over outer coating, is given longitudinal stripes of contrasting color.
The foregoing, together with further objects, features and advantages of my invention are set forth in the following description of specific embodiments thereof, wherein:
Fig. 1 is an elevation of a length of wire coded according to the preferred form of my invention and shown with successive layers removed to disclose the construction;
Fig. 2" is a view of a length of cable comprising wires. similar to that shown in Fig. 1, the wires in one end of the cable being splayed out into a flat. side-by-side relation to show by legends their several color combinations, the outer coating being shown as removed from the tip of each wire for the purpose of illustrating the color combination of the Wire;
Fig. 3 is a view of a wire similar to Fig. 1 but showing a modified form of my invention where the outer layer of contrasting color is applied as a pair of spaced longitudinal streaks;
Fig. 4 is a cross section of the wire of Fig. 3 but on an enlarged scale;
Fig. 5` is a somewhat diagrammatic longitudinal vertical section through an applicator for applying the coatings of the-wire;
Fig. 6 is a cross section of the applicator of Fig. 5 when adapted to apply the outer coating to the wire of Fig. 1; and
Fig. 'I is a similar cross section view showing the cross section of the applicator when adapted to apply the outer streak to the wire of Fig. 3.
The wire shown 1n Fig. l (which happens to be wire No. 22 of Fig. 2) comprises a copper conductor 25, insulation 2B, fabric braid 21, impregnation 28, under coating 29 and outer coating 30. The superficial film of colored parain usual on wire of this general type may be dispensed with, if, as I prefer, the coatings be made of a composition having sumcient wax-like ingredient to present a non-sticky and somewhat slippery surface. The Wireexcept for the fact it has two color coatings-may be the same as, and made by the same method and apparatus as, disclosed in detail in my before-mentioned patent. Brieily described, the assembled conductor, rubber insulation and braid is first dipped in a composition which may consist of stearin pitch, resin or synthetic resin, paraffin or other waxes and ller which impregnates and coats the braid. After the impregnation has set, the wire is then passed through a coating applicator having its discharge die heated above the melting point of the composition, which deposits a coating of a composition which may be the same as the coating composition except that it contains color pigment. If desired, the coating 29 may be omitted and the pigment added to the composition of the impregnation 28, although in practice I prefer to use the separate thin coating 29 of opaque material because the cost of the lessened amount of pigment used more than offsets the cost of the additional process. After the coating 29 has set, the wire is again passed through an applicator which applies the thin outer coating 30 in a similar manner. The outer coating 30 may be the same as the under coating 29 except that it is of different color.
The wire No. 22 (Fig. l) when used may be combined with similar wires of diierent color combinations into associated groups or into a formal cable 3l of the type customarily used in automatic elevator installations. In addition to the usual tensile wires 32 which are not conductors, the cable 3l as here shown comprises a group of twenty-four wires consecutively numbered in Fig. 2. Each of these has a different color combination as shown by the legends and as indicated by the lining on the wires. It will be observed that white over black and black over white, for example, are two different combinations (or more accurately permutations). In practice blacliI over black, white over white, red over red, etc. would be. indistinguishable from a single coating of black, white, red or the likn In such instances the wire having but a single naat-- ing of that color could be substituted in the code scheme.
In practice, also, it may be preferable to employ single colors for the rst few, or most frequently used, wires, employing color combinations only after the single color possibilities are exhausted. While in the illustration shown I have shown the use rst of black over each oi the several colors, then white over each of the several colors, then red over each of the several colors, etc., I appreciate that in many instances it will be preferable to employ iirst each of the several colors over black, then each of the several colors over white, then each of the several colors over red, etc. In the latter instance the orders could be iilled from a warehouse having a stock on hand of only two or three colors of single coated wire, over which the necessary additional color coatings could be applied to lill the order.
It is very desirable that where coatings are applied for the purpose of color primarily, they shall be as thin as possible. One reason is that the color pigments are relatively expensive and the amount of colored composition applied per reel of wire should be a minimum. Another reason is that it is advantageous to keep the overall diameter of the various wires the same so that wires with two color coatings will be of substantially the .same over-all diameter as those having only one. In fact it is a feature of the method and apparatus here shown for applying the outer coatings that the outer coating can be applied without sensibly increasing the over-all diameter of the wire with only the under coating.
The applicator shown in Figs. 5 and 6 is generally similar to that disclosed in my previously mentioned pending application to which reference is made for a more detailed discussion.
Referring to Fig. 5, the applicator comprises a block halved into upper and lower parts 33 and 34 held together by cap screws 35 and having mating channels constituting a longitudinal opening 36 of rectangular section extending from end to end. One end of the opening 36 is closed by a plug 37 having a bore 38. The wire to be coated is positioned by sheaves not shown to coincide with the axis of the anterior bore 38. The opposite end of the opening 36 is closed by a plug 39 having a bore 40 constituting a discharge die. The cavity formed within the opening between the plugs 3l and 39 is lled with the melted coating composition 4l (except for an air pocket which may incidentally be trapped at the top). Melted liquid composition is fed to the applicator from an upper reservoir or melting hopper (not shown) through a valved feed pipe 42.
The applicator is heated by a plurality of car- Il tridge-like electric heaters 43. Some of these are preferably placed adjacent the discharge plug 39 to insure that the bore 40 of the discharge die is kept heated to a temperature about the melting point of the composition despite the coole ing effect of the relatively cold wire passing through the applicator. I1" desired an auxiliary plug or sleeve 44 may be inserted in the opening 36 in abutment with the discharge plug 39 further to increase the heat conductivity to the discharge bore and prevent eddy currents adjacent the inner end of the discharge bore so that the friction of the wire on the melted composition within the larger bore of the auxiliary sleeve 44 tends to crowd the material against the belled or chamfered mouth of the discharge bore to insure a continuous flow of liquid thereinto.
The'anterior bore 38 is of such diameter relative to the on-coming wire that it presents no undue friction or scraping thereof but still is i,
suiliciently snug t so that the liquid composition, under its head pressure from the reservoir, will be checked by the friction between composition and the wire to prevent the composition from ilowing out the anterior bore when wire is passing through it.
The diameter of the discharge bore may be that of the incoming wire plus the coating to be deposited on it, as in my previously mentioned application; but I find it is also possible, and in many respects preferable, to make the discharge bore 4D the same diameter as the incoming wire. In that event it is preferable to make the bore shorter than disclosed in my prior application.
As the wire is pulled rapidly through the applicator in the direction indicated by the arrows it enters the applicator through the anterior bore 38 at substantially room temperature. As this is considerably below the melting point of the composition 4|, the latter tends progressively to congeal upon the wire. The wire passes through the applicator so rapidly that only a very thin layer is congealed. The hot discharge bore 40 insures that the outermost layer of the composition is melted and therefore of such liquidity that it lubricates the passage of the wire through the discharge bore and prevents the accumulation of any deposits on the surface of the bore. The thin fllm of the melted coating material l is deiinitely drawn into the discharge bore 40 between the wire and the bore. The thickness of this lm is not added to the radius of the resulting Wire but is absorbed by the material of the wire assembly. This is chiefly by the impression of the braid into the rubber insulation'. Thus the emerging wire as soon as the liquid coating has set after it leaves the hot discharge bore 40, is of the same diameter as the incoming wire. To a certain extent, depending upon the characteristics of the rubber insulation and of the braid, the diameter of the discharge bore 40 may be even less than. that of the incoming wire, although ordinarily it is of no object to have it less except it may be necessary to offset the tendency of the Wire assembly to come back, after' compression, toward its normal size.
The reason why I can with my applicator coat a very thin lm of wax-like material on to a wire having a surface of wax-like material of the same characteristics in the form of a prior coating or impregnation, without remelting the latter or causing it to run with the coating being applied, is this: The incoming wire is of room temperature and therefore relatively cool.4 The wire has considerable mass. The melted coating composition is a poor conductor of heat. The wire is passing through the body of melted composition very rapidly. The mass of the Wire especially near its surface absorbs such heat as is conducted through the film of melted material in surface contact with the wire before the previous coating or impregnation may be heated up to the melting point. Even when passing through the restricting hot discharge die 40', it is only the coating material adjacent the very surface of the bore which is kept melted. Also there are no factors tending to mix the outer coating with the inner coating within that Short interval of time even though the under coating should become plastic or even melted.
My coating apparatus and method is applicable to an impregnation as Well as a coating, but the benefits, as previously pointed out, are more marked in the solution of the problem of applying a very thin coating and especially to a wire which already has an impregnation or coating of similar material.
In Figs. 3 and 4 I have shown a modified form of my invention, The wire is the same up to and including the under coating 29'. The outer coating 30', however, is not applied about the entire area of the wire but only as one orl more spaced longitudinal streaks. This has the advantage of a ready identicaton of the Wire without having to remove any 'of the outer coating. As shown in the cross section of -Fig. 4, the outer coating 30' is preferably impressed into the surface of the wire so that its surface is at-the same radius as the surface of the exposed portions of the under coating. It will be understood vthat in Figs. 1, 3 and 4A the thicknesses of the coatings have been considerably exaggerated for clarity of the drawings.
In Fig. '7 I have shown a cross section of the applicator somewhat similar to Fig. 6 but showing only so much of the block halves 33 and 34 as lie adjacent the opening 36. This figure shows the cross section of the device of Fig. 4 as it is modified to produce the wire of Figs. 3 and 4. Here a pair of diametrically opposed longitudinal members 45 afford cylindrical surfaces of 90 arcuate cross section extending from the mouth of the anterior plug 31 tothe opposite end of the discharge plug 39 and in contact with the surface of the wire to prevent the liquid coating composition being applied, from coming in contact with certain arcuate portions of the wire. Thus the coating material is applied only to those regions of the wire which are not thus masked out by the members 45. This results in the streaklike coatings 30 of Figs. 3 and 4. The applied streak coating 30 Will be imbedded or compressed into the wire assembly for the same reason, as previously described, that the compression die applies a coating without enlarging the diameter of the Wire.
As in my previously mentioned application, the applicator is set at an inclination as shown in Fig. so that after applicator it may pass surface ofV a body of cooling Water be set before touching a sheave or any other guiding means which might otherwise impair the slick finish.
l. The method of coding and identifying individual conductors of a group of similar insulated electric conductors which consists in providing each individual conductor with a colored under coating externally of the insulation and an outer coating of a different color, some of the conductors having outer coatings of the same color and inner coatings of different colors, assembling the conductors in a group and scraping off regions of the exposed coatings to reveal the color of the under coatings without substantially impairing the insulation of the conductor as a whole at such regions.
2. The method of coding and identifying individual conductors of a group of similarly insudownwardly through the the Wire emerges from the CII and thereby lated electric conductors which consists in assembling into a group individually insulated electric conductors, each provided with a colored under coating externally of the insulation and an outer coating of a different color, some of the conductors having outer coatings of different co1- ors and under coatings of different colors,'and scraping off regions of the exposed coatings to reveal the color of the under coatings without substantially impairing the insulation of the conductors as a whole at such regions.
ALBERT "r. CANDY, Jn.