US3290757A - Method of assembling circuitry - Google Patents

Description

Dec. 13, 1966 F. J. TANCK METHOD OF ASSEMBLING CIRCUITRY Filed March 26, 1963 Fig. 2

FRANK J. TA/VCK INVENTOR. fiZnw/M ATTORNEYS United States Patent 3,290,757 METHOD OF ASSEMBLING CIRCUITRY Frank J. Tanck, Rochester, N.Y., assignor to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Filed Mar. 26, 1963, Ser. No. 268,013 1 Claim. (Cl. 29155.5)

This invention relates to an electric conductor assembly arrangement and, more particularly, to an apparatus and method for assembling a plurality of insulated electric conductor elements having a predetermined critical spacing.

In the art of electric conductors involving support of adjacent co-operating conductors which are respectively insulated, there are many complex arrangements for assembly which result in undue time and motion in accomplishing a complete assembly. A most troublesome problem is to assemble several closely spaced conductors having critical spacing relationships, particularly if the parts are small or difiicult to place in a particular location.

Therefore, an object of my invention is to provide a simple and reliable electric conductor assembly arrangement.

A more specific object is to provide an arrangement for assembling a plurality of closely spaced conductors.

In accordance with one embodiment of my invention, a plurality of severable electric conductors are formed from a single metal conductor unit to have small, high resistance support bridge connections between the elements thereof. This composite electric conductor unit is then secured to an insulated member by gluing, soldering, riveting, and the like, whereupon the high resistance bridge couplings are removed by coupling adjacent conductor elements in series with a high current source to vaporize the high resistance bridge couplings in the manner in which fuses are blown.

The subject matter which is regarded as my invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. The invention, however, as to its organization and operation together with further objects and advantages thereof, will best be understood by reference to the following description taken in connection with the accompanying drawing in which:

FIG. 1 is a perspective view of electric conductor elements partially assembled in accordance with the present invention; and

FIG. 2 is a detail plan view of a portion of the assembly shown in FIG. 1.

Referring now to the drawing wherein like numbers refer to similar parts, I have shown in FIG. 1 conductive elements 10, 11, 12, 13, 14 and 15. As is apparent from FIG. 1, the elements 10, 11, and 12 are formed from a single conductive strip of brass or the like to have small, high resistance bridges 17, 18, 19 and 20 of the same material therebetween. Such a construction may be fabricated by hand operations, but is often formed by a multistation punch press, which, by way of example, punches out unwanted portions, forms some portions, bends other portions, trims details, etc. The bridges 17-20, although of the same material as the conductive members -12, are relatively high resistance because of their small crosssectional area. Also, these bridges are curved slightly to raise them above an insulating platform 22 to which the conductive members 10-12 are secured. The particular platform 22 shown defines an aperture 23 through which wires, levers and the like may be inserted or fluids and the like may be transported.

The conductive members 13-15 (FIG. 1) have already been separated by vaporization of bridges 26 and 27 (FIG. 2). Prior to vaporizing these bridges, the conductors 13-15 were a single conductor, as shown in FIG. 2

3,290,757 Patented Dec. 13, 1966 and were secured by glue or the like to an insulating plate 28. The plate 28 is secured to the platform 22 as an integral part thereof with a step therebetween having a riser 29 to provide additional support to the conductive :members 10-12.

The original separation of the bridges 17-20 and 26-27 from the flat, smooth supporting insulator prevents the building up of substantial heat and vapor pressure which might tend to loosen the conductors from the support. This problem is further alleviated by the provision of recesses 31 and 32 in the insulating plate 28 in the region immediately adjacent to the bridges 26 and 27, which are to be vaporized. The recesses 31 and 32, in combination with raising the bridges 26 and 27, prevent charring of the insulation, which might result in a leak current flow, and further prevent damaging deposition of any conducting vapor resulting from the vaporization step. There are, of course, insulative materials such as polytetrafluoroethylene, which are not subject to charring or deposition considerations. The use of such materials would reduce or eliminate the need for such recesses. However, we prefer to use recesses 31 and 32 and equivalent recesses 33 in the region of the bridge 17-20. As an alternative,

the conductive portions adjacent to the bridges 17-20 could be raised substantially from the insulating platform 22.

It should also be noted from FIGS. 1 and 2 that another bridge 34 is provided in the central portion of the conductor 15 whereby the conductor 15 is substantially identical to the conductors 13 and 14 prior to the bridge 26 being removed. Moreover, these conductors 13-15 are relatively small and, therefore, somewhat difiicult to position individually on a smooth surface of the type presented by the insulating plate 28. The assembling of the small conductors 13-15 as a single unit results in substantial labor savings. This is particularly true if the access to the final assembly is substantially covered by other equipment (not illustrated) as is often the case in practice.

In FIG. 1 the conductive member 10 is provided with a portion 35 which is supported by the riser 29. This portion has there-on a contact button 36 suitable for engaging a portion of a battery 38 (shown in phantom). The conductor 11 is provided with a similar portion 39 having two such raised buttons 40 and 41 to engage batteries 42 and 43 (in phantom), and the conductor 12 is provided with a similar portion 44 having a button 45 to engage a battery 46. Further support of the batteries 38, 42, 43 and 46 is provided by the plate 28 and by the conductors 13-15, which are provided with resilient fingers 48, 49, 50 and 51 to engage the other ends of the batteries.

The assembly thus described is arranged to energize a load means such as a lamp 53 coupled in circuit with the conductors. In this instance, the lamp 53 is coupled serially between the conductors 13 and 14 so that after the conductors 10-12 are isolated by vaporization of the bridges 17-20, the lamp 53 may be energized by all four batteries whenever a disc contactor 54 (shown in phantom) is rotated to have a conductive shoe 56 thereof engage a pair of contact arms 57 and 58 of the conductive members 10 and 12 respectively. Similarly, the lamp 53 may be energized by only two of the batteries (43 and 46) by coupling of contactors 60 and 61 by a contact arrangement, not illustrated.

In order that the contact arms 57-58 and the contactors 60-61 may be reliably coupled by their respective operators, the relative spacing of the conductive members 10-12 is critical. Also, the spacing of the battery contact buttons 36, 40, 41 and 45 must be within reasonable limitations. As is often the case, the relative spacing of these parts is more critical than the absolute location. For instance, under certain environmental conditions, A" spacing between parts 10, 11 and 1-2 is acceptable, but is assembly provides assembly tolerances of less than Obviously, jigs and fixtures may be simplified using my invention as well as reducing the assemblers time and motion.

Referring now to FIG. 2, the bridges 26 and 27 may be vaporized by coupling one terminal of a high current source 64 to the conductor 14 by means of a probe 65.

The other terminal of the high current source 64 is connected through a switch 66 to the conductors 13 and 15 through probes 68 and 69. In the particular construction illustrated, care must be maintained to position the probe 68 in the region of the finger 49 so that the bridge 34 is not vaporized, as these two fingers 48 and 49 must remain electrically coupled to accomplished the complete series array of the batteries 38, 42, 43 and 46, as illustrated in FIG. 1.

In FIG. 1, the high current source 64 (or a similar source) is couplable by the switch 66 to electrodes 65', 68 and 69' to accomplish vaporization of the bridges 17-20. Once separation of the conductors -12 is accomplished, the disc contactor 54 may be rotated in a programmed manner by turning of its shaft (not shown),

which supports the disc contactor 54 in a predetermined engaging spacing relative to the contactors 57 ad 58 by means of a bearing aperture 71 in the platform 22. A similar bearing aperture 72 is provided for the contact used to engage the contactors 60 and 61.

While I have shown and described particular embodiments of the present invention, other modifications may occur to those skilled in this art. For instance, if only two conductors are to be assembled simultaneously, only two probes (68 and 69) need be used. On the other hand, if many elements are assembled as a unit and then separated by vaporization, there will be more probes arranged to couple alternate elements to opposite sides of the high current source. Similarly, several switches (66) may be used to accomplish vaporization in a sequential manner wheresupport of one element is accomplished from several adjacent and coupled-together elements. Also, the conductive members 10-12 could be coupled by bridges to locate the conductive members 13-15. But

usually the economics of assembly would not fully justify the substantial increase of scrap of such an arrangement. Furthermore, my invention may be advantageously used to assemble a single element in relatively inaccessible locations whereupon once the element is secured, an integral handle may be severed therefrom by my vaporization technique. I intend, therefore, to have the appended claim cover all modifications which fall within the true spirit and scope of my invention.

I claim: A method of producing an electrical conductor assembly arrangement having an insulating base and at least two shaped conductive elements fixed to the insulating base in a critical predetermined spacing relationship relative to each other, comprising the steps of:

forming the conductive elements from a single strip of conductive material with at least one integral high resistance bridge of substantially reduced cross section integrally joining the elements as a single piece;

shaping the elements to the desired shape and bending the bridge to form a curved bridge raised relative to the portions of the elements adjacent the bridge and to establish and maintain the predetermined spacing between the elements; forming the insulating base with surface areas for securing the elements thereto and forming a recess in the insulating base between the surface areas;

securing the elements directly to the surface areas of the insulating base with the curved bridge directly over the recess and spaced from the insulating base by the amount of raising and the amount of recess;

and coupling the elements in series with a high current electrical source to vaporize the high resistance bridge and separate the joined elements without damaging the insulating base, or loosening or affecting the spacing between the elements secured to the base.

WHITM'ORE A. WILTZ, R. W. CHURCH,

Assistant Examiners.

Images