US2123506A - Solderless lug - Google Patents

Description

July 12, 1938. F.. FRANKEL. JR 2,23,506

SOLDERLESS LUG v t Filed Sept. 15, 1956 l @MENTOR @ff v ATTORNEY.

Patented July 12, v193s UNITED sra-.TasV

PAT-ENT OFFICE y SOLDERLESS LUG Ferdinand Frankel, Jr., New York, N. Y. Application September 15, 1936, Serial No. 100,801

3 Claims.

My invention relates to a cable connecting device and more particularly to a solderless lug.

It is the principal and general object of the invention to provide an improved, eiiicient de- 5 vice of the character indicated which will eiiectively perform its function.

It is a more specic object of the invention to provide a device of the character indicated which is adaptable for use with cables oi different sizes.

Another object is to provide a simple form of device in which there will be a substantially maximum area of contact between the cable and the conducting portions to be connected thereto.

Another object'is to'provide a device of the character indicated, formed of metal, and in which the objection of season cracking is reduced to a minimum. y

Other objects and various features of invention will be hereinafter pointed out or will become apparent to those skilled in the art.

In the drawing which shows, for illustrative purposes only, a preferred form of the invention Fig. 1 is atop plan view of a solderless lug, illustrating features of the invention;

Fig. 2 is a sectional view taken substantially in the plane of the line 2 2 of Fig. l;

Fig. 3 is an end view of the lug shown in Fig. 1 and indicating a small cable therein; and

Fig. 4 is a similar view of the same lug butl indicating a larger cable therein.

In said drawing, 5 indicates generally a contact member in the form of a blade which is to be connected to a second contact'member or cable -6. In the preferred form, the blade 5 is formed I of at copper, folded upon itself at 1, andA provided, with complementary channeled contact portions 8 9 which are separated from, each other to embrace a cable. Such separation may sa be effected by forming up one rear blade portion,

40 as indicated at I Il, so as to-provide an oiset and thus space apart the contact portions or members 8 9. The contact member 8 is formed up so as to embrace a cable and is of generally Ul form as clearly appears in Figs. 3 and 4. The legs I I II of the U extend up a considerable distance and the contact member 9 preferably fits snugly between and is guided by the legs II as shown in said gures. The upper contact member 9 is preferably formed, as indicated at I2, to embrace a cable andthe outer edges may be flanged up, as indicated at I3-I3, which flanges may pass down between the legs II I I, and thus the two contact members are guided relatively to each other so that there can be little or no twisting or mis- 56 alignment of the'same. The contact member 9 (Cl. 173-269) l is provided with a stili' backing shoe I4, preferably formedof suitable metal not readily corrodible member 9 so that the shoe will be securely held to and back up the contact member. In fact I prefer to taper or dovetail the shoe I4 so as to assure a tight interlock between the shoe and the contact 9 and anges I3. 10

I provide means for urging the contact mem` bers 8 9 into tight clamping engagement with thecable 6 and in the form shownI prefer to employ what may be termed a yoke I5, formed to extend over the shoe I4 and the coacting mem- 15 ber 9. The yoke I5 may have legs I6 I6 straddling said shoe and extending downward into contact with the legs I I I I of the contact member 8, and in fact I prefer to hold the yoke I5 and contact member 8 against longitudinal relative 20 displacement by forming intertting portions thereon as by rabbeting one and forming end tongues on the other as indicated atl I'I, whereby the yoke' I5 and contact member 8 will beheld against longitudinal displacement from each 25 other. Lateral v'disengagement is prevented by the flanges4 I3 I3. The yoke and contact member 8.

I and in fact all of the parts, are held against displacement by means preferably in the form of an endless strap or sheath I8. 'The sheath I8 ts 30 snugly around the contact member 8 and the yoke I5. In order to clamp the-cable rigidly between the contact members 8 9, I provide means preferably in the form of one or more screws I9, of a Well known headless variety, provided with a central wrench socket 20. The screws I9 in the form illustrated are screwed into threaded holes through the yoke I5 and engagethe at upper surface 2l of the shoe I4, as will be clear.. The sheath I8 is provided with apertures 22 to render 40 the clamping screws I9 accessible.

My improved lug lends itself to use in connection with cables of different sizes, that is to4 say, the lug may be designed to take cables, for example from 1,000,000 circular mils to 750,000 cir- 4.', cular mils with substantially equal conducting and other efficiency. vI prefer to make the cross-sectional form of the lower arcuate part of the contact member 8 such that it will just t the smallest cable for which the lug is designed (see Fig. 3) 50 thereby at once securing about 180 contact with the small cable. The contact member 9 is preferably of a curvature to t a cable intermediate the largest and smallest cables for vwhich the particular lug is designed. Therefore,.for the entire range of cable sizes for which the lug is designed, the curvature of the contact member approximates the cable curvature and good contact is obtained. When a larger cable is inserted in the lug (see Fig, 4), the cable will not t the arcuate portion of the contact member 8 exactly, but when the screws I9 are screwed home the contactmember 9, backed up by the stiff shoe I4, will force the cable down and cause the side walls of the-contact member 8 to be spread or opened up to an extent suflicient to make a good contact with the larger cable. It will be seen that in effect the U -shaped contact member 8 and sheath I8 form a sling for carrying a cable and the latter is held in tight clamped engagement and in good electrical contact with both the contact members.

It will benoted that by-reason of the reforming of the contact member to fit the cable, the original lay of the strands of the cable will be distorted as little as possible and the best possible contact between the various strands obtained.

Preferably, the screws I9, if of the headless kind, are of such length that when the cable oflargest size is rigidly clamped the screws will be substantially flush with the outer surface of the sheath I8 and when a smaller cable is employed,

the tops of the screws will be below s uch sheath. Thus, a sightly lug is produced and one in which there-are no 'projecting screws.

The proportioning of the parts is preferably such that when the largest-cable is in place and tightly clamped in the lug, the folded portions of the blade 5 will just contact with each other. When a smaller cable is gripped there may be some buckling of the blade 5 but the blade will give at I0 and when the blade is clamped ilat on a bus bar all buckling will be removed. Furthermore, it will be noted that, with the stiff shoe Il, a very full and good contact between the contact member 9 and the cable will be secured, due to the fact that the contact member 9 while being forced into engagement with the cable will not buckle and flare Yup at the ends or edges as would be the 'case if the screws engaged the contact member 9 directly rather than through the 'stiff shoe which serves to rigidly back up the contact member 9 and cause it to maintain contact substantially throughout the length of the cable Inserted in the lug. My improved lug having the blade portion 5 andthe contact members 8-9 all integral provides the best possible conductivity between the cable and the blade. The sheath or sleeve which surrounds all parts-of the lug and servesto ultimately take the strain incident to clamping of the cable between the contact members is preferably made of metal, is not subject to corrosion nor lis it subject to season cracking. 'Ihe same thing may be Isaid of the shoe I4 and the yoke block I5, as well as the screws I9, when surface to bettergrip the cable.

It will be seen that I have provided a solderless lug providing very extensive and excellent contact with a cable. The parts are all quite simple and cheap to manufacture and the entire device is handled and applied as a unit. There are no parts which are likely to become disengaged and lost.

While theinvention has been described in considerable detail and a preferred form illustrated, it is to be understood that various changes and modifications may be made within the scope of the invention as defined in the appended claims.'

I claim:

l. In a device of the character described, a blade formed of flat metal folded intermediate its length, the ends of said blade being spaced apart and oppositely channeled to form jaws providing a substantially circular pocket for a cable end, one jaw being slidable between the side walls of the other jaw, a stiff shoe resting on the outer surface of one of said blade ends, a yoke overstanding and straddling said shoe and engaging the edges of the other blade end, means for interlocking said engaging edges to prevent inde-y pendent longitudinal movement of said yoke and blade end, a strap surrounding all of said parts. and a screw passing through said strap and threaded through said yoke and engaging said shoe to force the latter forwardly, for the 'purpose described. Y

-2. In a device of the character described, a blade formed of flat metal folded intermediate its length, the ends of said blade being spaced apart and oppositely channeled to form a substantially circular, pocket for a cable end, a stil! shoe resting on the outer surface of one of said blade ends, a yoke overstanding and straddling said shoe and engaging the edges of the other blade end, a strap surrounding all of said parts, a screw passing through said strap and threaded through said yoke and engaging said shoe to force the latter forwardly, for the purpose described, the side edges of the blade end supporting said shoe being bent upwardly betweeny said shoe and the adjacent portions of the yoke and bridging the lines of engagement betweensald yoke and the other blade end.

l3. In a device of the character described, a contact member formed of flat metal folded intermediate its length, the ends being spaced apart, one end being channeled longitudinally to form a jaw for receiving one side of a cable end. the other end being oppositely channeled longitudinally to form a second jaw for engaging the opposite side of said cable end, the sides of said second jaw extending between and guided by the side walls of the first mentioned jaw as the jaws are caused to approach each other, a stiff shoe at the outer side of and also extending between the side walls of the rst jaw, a yoke overstanding said shoe and having a threaded passage, a clamping screw adjustable in said passage toward and from said shoe, and a strap surrounding all of said parts excepting the outer end of said screw.

FERDINAND FRANKEL, Jn.

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