US 1943020 A
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Description (OCR text may contain errors)
Jan. 9, 1934. K. v. JOHNSON CABLE TAP CONNECTER File d May 11, 1929 Invenfor Ii 07'! V Jb/wn .5022
Patented Jan. 9, 1934 UNITED STATES PATENT orrics This invention relates to a cable tap connecter and has as its primary object the provision of a device for effecting electrical connection between a main feed cable and one or more tap lines for diverting current from the main cable.
Another object is to provldea device of the above character which is especially applicable for use on cables and tap lines arranged in conduits with their intersections located in accessible raceways or troughs where space is limited, and whereby tap lines may be readily connected to the main cable without severing the latter and without necessitating soldering the connection with the main cable.
Another objectis to provide a cable tap connecter so constructed that when applied it may be conveniently and thoroughly insulated with a minimum of insulating material and labor.
Another object is to provide a cable tap connecter which is so constructed that it may be quickly put in place with small possibility of being accidently separated from the 'main cable while being applied, thus rendering it especially desirable for use in tapping live cables.
Another object is to provide a cable tap connecter which is compact and of such shape as to require no more space than the main cable and the maximum sized tap cable combined, and which is so designed as to aflord the largest contact area possible for its size.
In the electrical industry it frequently occurs that tapped lines have to be connected to heavily charged wires and cables and in many instances at points where very little space is ail'orded in which to work. In most cases such wires and cables are run in metal conduits and have their intersections located in metal raceways which are grounded, and accordingly utmost caution must be used to keep the live parts from contacting the raceways and accordingly my invention contemplates the provision of a cable tap connecter which will afford means for bringing the tap to the main conductor either from the right or left or top or bottom, as the case may be, with the tap lines leading parallel with the main conductor and to provide a connection which will occupy a minimum of space so as not to contact the enclosing raceway.
Another object is to provide a cable tap connecter which isadapted for use in eilecting connection of one or more tap lines to the cable at a single intersection with the latter, and also to provide means whereby two tap lines of diilerent capacities may be readily applied. v
With the foregoing objects in view, together with such other objects, purposes and advantages as may subsequently appear, my invention resides in the parts and in the combination, construction and arrangement of parts hereinafter described and claimed and illustrated by way of example in the accompanying drawing in which:
Figure 1 is a side view of the connecter showing it as applied.
P18. 2 is a detail in cross-section as seen on the line 2-2 of Fig. 1, showing the connecter in end elevation with portions broken away.
Fig. 3 is a perspective view ofa tap line terminal employed in the device.
Fig. 4 is a perspective view showing the assembled connecter as detached.
Referring to the drawing more specifically, A indicates a main cable or conductorcovered with an insulating sheath 5, B designates a tap line conductor covered with an insulating sheath 6, and C designates generally the tap connecter embodying the present invention. The connecter 0 includes a pair of separable clamp members '1 and 8 each of which is formed with clamplnglaws 9 and 10 at its opposite ends;" the Jaws 9 being adapted to be positioned astride the cable A at a point where a portion of the insulating sheath 5 has been removed to receive the connecter as shown in Fig. 2, and the Jaws 10 are adapted to be positioned astride a cylindrical shank 11 on a tap line terminal D shown in Fig. 3. The clamp members 7 and 8 are formed of conductive materal and are complementary in contour and crosssection and are formed of suitable corresponding lengths and, when assembled, are arranged with their corresponding end iaces aligned and are detachably connected together by means of one or more screws 12, the heads of which are countersunk in the clamp member 7 and the threaded shanks 01' which extend through openings 13 in the clamp member '1 and are screwed into engagement with threaded openings 14 in the clamp member 8; the screws being located to connect the clamp members 7 and 8 at points between the laws 9 and 10 so that the screws will extend between the cable A and shank l1 oi. the terminal D as shown in Fig. 2. The openings 13 areof smooth bore and have diameters slightly greater than the diameters of the shanks of the screws 12 whereby the latter may be thrust longitudinally through the openings in eflecting initial engagement of the screws with the threaded openings 14 in clamp member 8 in assembling the connecter, and whereby on turning either screw to advance it in or out at its companion opening 14 the jaw member 8 will be advanced or retracted relatively to the jaw member 7. The jaws 9 are formed of a thickness substantially corresponding to the thickness of the sheath 5 on the cable A, so that when applied to the latter, they will not project beyond the periphery of the insulated cable.
In order to insure intimate contact of the jaws 9 with the cable A and of the jaws 10 with the shank 11, the contiguous faces of these jaws are formed throughout their widths with arcuate concave recesses, the surfaces of which are smooth and are formed on segments of circles so as to conform to the cylindrical surfaces of the cable and shank; these arcuate recesses on each jaw being slightly less than a semi-circle so that when the jaws are applied to the cable and shank they ill extend nearly throughout the circumferences thereof, with a perfect machine fit so as to eliminate corrosion of the contacting surfaces of. the jaws. The clamp members 'I and 8, when applied, will thus be spaced a slight distance apart so that on tightening the screws 12 they may be securely and tightly clamped against the surfaces of the cable and shank; the screws 12, by reason of being interposed between the pairs of jaws, serving to advance both pairs of jaws collectively to their clamping positions on tightening the screws.
The tap terminal D is formed at one end with. a lug 15 having a recess 16 for the reception of the end portion of the cable B to afford the connection between the terminal D and the tap cable. In order to effect secure engagement between the tap line conductor and terminal, the end portion of the tap line conductor is soldered in the lug 15.
As a means to facilitate positioning of the terminal D between the jaws 10 the outer end of the terminal is formed with a head or flange 17 which is spaced from a shoulder 18 constituting the inner end of the lug 15 at the intersection of the latter with the shank 11; this space being substantially equal to the width of the jaws 10 so that when the device is assembled the inner face of the head 17 and the shoulder 18 will extend contiguous the end margins of the jaws 10, as shown in Fig. 1. This head 17, cooperating with the shoulder 18, serves to prevent longitudinal movement of the shank 11 relatively to the jaws 10 both during the operation of positioning the shank 11 between the jaws 10 and after effecting engagement of the shank by the jaws 10.
As a means for enabling the connection of a second tap line conductor E to the terminal 11 on the end thereof opposite the sleeve 15, the outer end of the shank 11 is formed with a lug recess 19 which opens through the head 17 as shown in Fig. 3; this recess being adapted to receive the end of a tap line conductor of a size smaller than that of the tap line conductor B. The end of the tap line conductor E may be soldered in the socket 19. i r
The lug 15, with its recess 16, is designed to receive a tap line of large carrying capacity; it being preferably formed to receive the ends of conductors capable of carrying an electrical current ranging from a minimum of twenty-five percent of the capacity of the main cable A upward, and the lug recess 19 is designed to receive the end of a tap line conductor of small capacity such as one capable of carrying an electrical current ranging from twenty-five percent of the capacity of the main cable A downward.-
In the application and operation of the invention, a portion of the insulation 5 of the main line conductor A is removed to expose the cable A for a distance substantially corresponding to the width of the jaws 9 as shown in Fig. 1 whereupon the clamp member 8 is positioned with the recessed inner face of its jaw 9 abutting against the exposed portion of the cable A. The shank 11 of the terminal D, with either one or both of the tap line conductors B or E attached thereto, is then seated in the recess of the jaw 10 of the clamp member 8 whereupon the clamp member '7 is positioned with its jaws seating on the cable A and shank 11. In thus assembling the terminal D between the clamp members, the
flange 1'7 and shoulder 18 will serve, by reason of abutting against the-ends of the clamp members, to hold the terminal against longitudinal movement relatively to the clamp members thereby minimizing any possibility of the terminal being accidentally disengaged from the clamp members during the assembling operation. The screws 12 are then inserted through openings 13 in the clamp member '7 and secured into engagement with the threaded openings 14 in the clamp member 8 in such manner as to tightly clamp the pairs of jaws 9 and 10 into intimate contact with contiguous surfaces of the cable A and shank 11. The connecter, when thus applied, will occupy a space substantially corresponding to that occupied by the cable A and the tap line conductor B. A suitable insulating wrapping is then applied so as to thoroughly cover the clamp members 7 and 8 and the terminal D.
The use of this cable tap connecter will result in asaving of time, of space and of materials and obviates the necessity of eflecting a soldered connection with the main cable thus eliminating heating of the connection due to such soldering and thus obviating injury of the insulation ordinarily due to such heating.
By the arrangement of the tightening screws set forth a balanced or equal pressure on both the conductor and the tap line terminal will be effected.
Whereas I have shown and described a specific embodiment of my invention I do not limit myself to the specific construction and arrangement shown and may employ such changes as may come within the scope of the appended claims, for example, in some instances, the terminal D may be dispensed with, as where it is desired to connect a single tap line conductor having such 1 diameter that it may be clamped directly between the jaws 10.
1. In a cable tap connecter, a tap terminal including a cylindrical shank having aflange at one end and a shoulder at its other end. said shank being formed at each end thereof with a tap-wire receiving socket for the reception of and engagement with the ends of tap-wires, a pair of electrically conductive clamp members, jaws at one end of said clamp members adapted to receive the shank of said terminal, said jaws being formed to extend between the flange and shoulder of said terminal in close contact with said shank substantially throughout the portion thereof extending between said flange and shoulder, 9. pairof jaws on the other end of said members adapted to extend astride of and to substantially encompass a cable, and screw means inter-connecting said clamp members intermediate the pairs of jaws operable to collectively advance the jaws into engagement with the terminal. and cable.
2. A ca le tap connecter comprising a cylm- 1,948,020 drical shank having a fiange at oneend thereof and formed with a socket in its flanged end adapted to receive the end of a tap-wire in permanently fixed engagement therewith, a terminal lug formed on the other end of said shank integral therewith having a socket therein of larger diameter than said first named socket adapted to receive in permanently fixed engagement the end of a tap-wire of greater capacity than said first named tap-wire, a shoulder at the intersection of said shank and terminal lug, said shank being of'uniform diameter throughout the length thereof extending between said flange and shoulder, a pair of electrically conductive clamp members, arcuate' jaws at one end ofsaid clamp members engageable with said shank and formed to contact said shank substantially throughout the surface thereof extending between said flange and shoulder, arcuate jaws at the other end of said clamp members for engagement with a cylindrical cable and formed to substantially encompass the cable; and screw means interconnecting said clamp members intermediate the pairs of jaws for collectively advancing said jaws into engagement with said shank and cable.
KARL V. JOHNSON.