US1644306A - Cable connecter - Google Patents

Description

Oct. 4, 1 J. c. LEDBETTER CABLE GONNEGTER Filed Sept. 11. 1925 INVENTOR James [gmrod Lealieller q' i M Patented a 4, 1927.

UNITED STATES PATENT OFFICE.

STAKES OAIBOD LEDBET'IER, OE NEW YORK, N. Y., ASSIGNOB TO THE THOMAS & BETTE (70., Q! ELIZABETH, NEW JERSEY, A CORPORATION 01' NEW JERSEY.

I casts commc'rna.

Application fled September 11, 1925. Serial No. 55,668.

This invention appertains to cable connecters and relates more particularly to sleeve connecters having improved wire bushings and having improved cable clamping means to secure the cable in the sleeve.

Primarily a urpose of the invention is to improve cab e connecters in respect to the wire bushings therefor which more effectively protect the insulated or rubber covered wire extremities which pass from the metal armored cable out through one end of the sleeve to the electrical fixture box; and furthermore a purpose is to improve the connecter in respect to the cable clamping means b which thearmored cable is secured in the s eeve connecter.-

A still further object is to improve split type expansible sleeve connecters by embodying therein a lining which laps across the splits of the sleeve to cover said splits to provide a well covered and sealed interior sleeve structure thereby preventing the exposure of any portion of wire within the sleeve, and integral with said lining there is formed a flexible bearing clamp plate, and in addition thereto a wire bushing is integrally formed with the lining, the three elements in effect being stamped in one piece from sheet metal.

An additional purpose is to seal the connecter against leakage of sparks should by chance any occur in the connecter and thereby reduce the fire hazard and the improved bushing and lining are for this purpose.

Other objectsof the invention will be understood from the following description and the accompanying drawing which illustrates preferred forms of the construction and modes of use.

Figure 1 shows a longitudinal sectional view of an assembled electrical fixture box with a cable connecter attached to the box and a cable secured in the connecter.

Figure 2 shows a longitudinal sectional view of a cable connecter removed from the box and removed from the cable.

Figure 3 shows a plan view of the cable connecter, Figure 4 an elevation of the inner end thereof, and Figure 5 a side elevation.

Figure 6 shows a cluster view of the comosite full fashioned circular wire bushing mtegrally made on a bearing clamp plate, the two views showing this art in the proces of manufacture and be ore the bushing is bent right angular to the plate, while Figure 7 illustrates the bushin and bearing three integrally formed elements, name bushing, a clamp plate, and lining plates.

igure 8 Fi re 9 shows the stampin o ,comp etely formed up and ma e ready to be inserted within the s eve.

Figure 10 shows a cross section and longitudinal section of a split sleeve type connecter embodying the modified form of stampingshown in Figures 8 and 9.

In electrical construction, it becomes neces sary to fasten armored cable C in the knockout openlngs or holes H in electrical fixture boxes B and the rubber covered or insulated wire extremities W must necessarily be protected from ,damages at the point where they leave the frequently sharp jagged end of the metal armor C and enter the box B; and this invention affords improvements for effectlvely carrying out the foregoing electrical installation work.

An improved full fashioned complete circular bushing combined with a bearin clamp plate is shown in Figures 6 and 7 and this device is adapted for use in connection with a sleeve connecter particularly an expansible connecter and comprises a punched, drawn and flared bushing 12 integrally made on a strip of metal constituting a bearing clamp plate 13 which not only carries the bushing 12 at one end but carries a suitable means at its other end for attaching the device to one end of a sleeve, and in this instance ears 14 are employed to attach the device within a sleeve.

The sleeve connecter with which the improved bushing and clamp plate is combined may assume any, suitable form but for the purposes of this description, there is shown a split type expansible sleeve comprising a single stamping in which half-round cooperating or mating sections 16 and 17 remain integrally connected by necks 18 to a cable receiving ring '19 when the stamping is punched from sheet metal. End radial or circumferential slots or openings 20 are punched in the connecter blank from which the split sleeve is fashioned and after the stamping is completely formed into a connecter as a sleeve, there remain the longitudinal slits 21 extending from the radlal slots 20 through the other end of the sleeve 164-17. These slits are open entlrely throughout the length of the sleeve and thus enables one end of the sleeve to expand inasmuch' as the sections 16 and 17 readily bend at the neck 18 relatively to the stationary ring 19. t

Connecter anchorage means 1s provided by which the sleeve is positively anchored within the box hole H. To this end a box edge receiving groove or channel 23 is stamped and pressed into the free expanding end of the sleeve and the groove 23 is adapted to rest and expand against the box hole rim H thereby positively locking the connecter sleeve in the box B.

Suitable cable clamping or operating means such as a screw 25 is carried in one of the expanding sleeve sections and this screw cooperates with the clamp plate heretofore described to secure the cable in the sleeve and simultaneously expand the connecter sections 16 and 17 in the box hole, and the pressure of the screw is distributed lon i- III tudinally along the cable armor C in t e sleeve to increase the positive holding effect as between the cable and sleeve as will be described.

The improved bearing clamp plate illustrated in Figures 6 and 7 is placed in the connecter sleeve 16 17 and the ears 14 thereof are bent over as shown in the assembly .views thereby forming the ears into hooks 14 extending through the slots 20 straddling the'neck 18 and being pressed down on the outside thereof. The two hooks 14 are disposed adjacent the neck 18 and act to hold the bushing 12 in proper position at the expanding end of the sleeve and at the same time the ears or hooks 14 remain positively in place due to the narrowness of the slot 20 and because of the close proximity of the neck 18. The clamp plate 13 is mounted directly underneath the screw so as to receive pressure therefrom and bulge downwardly by operation of the screw and thus bear upon and along the cable in the sleeve which tightly sets the armor of the cable into the ring 19.

In assembling the cable, the connect/er, and the box, the mechanic inserts the cable C in the connecter and projects the wires W thereof through the bushing 12 and inserts the connecter anchorage grooves 23 in the box hole H whereupon the screw 25.is run down against the clamp plate 13 thus bend- I ing and developing it downwardly serving to bear the cable 0 positively against the lower sleeve section 16 and serving to press the armor cable C against the ring 19 as well.

This action of the screw and the bearing plate positively anchors the cable and connecter in the box and the parts are as readily disassembled and removed from the box as they are installed therein.

Referring now to the modified form of the invention shown in' the last three views, the sleeve is the same in structure as already described and is so numbered but the bushing and clamp plate are further improved by addition thereto of lining plates 30 integral with the clamp plate 31. In this improvement, a bushing 32 is punched and drawn at one end of the clamp plate 31 and, ear hooks 33 are made on the other end thereof. The two lining plates are integrally attached to this stamping by connecting necks 34 which in effect leaves splits 35 defining the clamp plate 31 thereby leaving it flexible under the pressure of the screw 25.

The Figure 8 stamping is subjected to a forming operation which imparts circular or cylindrical form thereto somewhat smaller in diameter than the inner diameter of the sleeve but large enough to receive the cable C thereinto. The advantage of this lining plate structure resides in the fact that the sleeve slits 21 are overlapped and sealed by the two side lining plates 30 and so it matters not that these slits 21 are rather wide or open up rather wide for they are sealed from the inside of the sleeve.

It follows therefore thatin case any portion of the wire W near the bushing 32 should be exposed or uncovered by reason of a rough angular or ragged cut made at this end of the armor C, the lining plates or curved sections 30 cover and seal these'exposed parts which increases the safety of the device by reducing the fire hazard because sparks or arcs, should such occur,cannot possibly escape through the sleeve slits 21 because they are sealed.

What I claim is:

1. A cable connecter comprising, a sleeve including anchorage means adapted to be fixed in a box, a separately made full fashioned circular bushing movably disposed within the sleeve at one end through which the wires of armored cable pass and against which the end of the armor of a cable stops, a strip of metal forming a clamp plate made integral with the bushing and extending along the inside of the sleeve toward the other end thereof, means on one end of the clamp plate to attach it to the sleeve, andthrough which the wires of armored cable pass and against which the end of the armor of a cable stops, a strip of metal forming a clamp plate made integral with the bushing and extending along the inside of the sleeve toward the other end thereof, means on one end of the clamp plate to attach it to the sleeve, and operating means carried on the sleeve adapted to bear on the clamp plate to press the cable and secure it in the sleeve andsimultaneously expand the split sleeve rendering operative the aforesaid anchorage means.

3. A cable connecter comprising, a sleeve including anchorage means by which it fastens ina box, a bearing clamp platedisposed in the sleeve, means at one end of the plate to connect it with the sleeve, a complete full circular bushing integrally made on the other end of the plate and loosely confined in the sleeve end, and a screw mounted in the sleeve adapted to force the plate against a cable received into the sleeve. 4. A cable connecter comprising, a split sleeve with anchorage means by which it fastens in a box, a bearing clamp plate disposed in the split sleeve, means at one end of the plate to connect it with the split sleeve, a complete full circular bushing integrally made on the other end of the plate and loosely confined in the split sleeve end, and a screw mounted in the sleeve adapted to force the plate against a cable received into the split sleeve and simultaneously expand the split sleeve to render effective the aforesaid anchorage means.

5. A. cable connecter as defined in claim 2 further characterized by cylindrical lining plates integral with the clamp to form an internal lining int e sleeve and around a cable therein received.

6. A cable connecter as defined in claim 4 further characterized by cylindrical linin plates integral with the clamp plate adapte to form an internal lining in the sleeve and around a cable therein received and to over lap the splits in the sleeve.

7. A cable connecter comprising, made with oppositely gitudinal slits thereln expand and anchor made with radial slits adjoining the longitudinal splits, box made on the sleeve, a strip of metal constituting a clamp plate adapted to bear against a cable and secure it in the sleeve, ears on one end of the plate bent up through the a sleeve hole,

late adapted disposed parallel Ion-Y. to enable one end to. itself in a box hole and hole anchorage means radial slits to attach the plate in the sleeve, 9. full fashioned complete circular bush ng integrally carried on the other end of the plate, and a screw carried in the sleeve adapted to bear upon the plate between earsand the bushing.

8. A cable connecter as defined in claim 7 further characterized by a cylindrical lining plate disposed on each side of the clamp plate adapted to overlap and cover the aforesaid slits in the sleeve.

9. A cable connecter comprising a sleeve provided with longitudinal slits running through one end and approximately to the other end to enable one end of the sleeve to expand to anchor the connecter in a box I box hole anchorage means made on the sleeve, a screw mounted in the sleeve adapted to expand the sleeve end aforesaid, a stamping made with parallel splits therein, a cable clamp plate formed between the stamping splits and disposed in alignment with the screw and adapted to be pressed downwardly against a cable by said screw, means on one end of the plate to movably attach it to one end of the sleeve; and a pair posed on each side of the clam plate, adapt-.

ed to overlap and cover the a oresaid longitudinal slits in the sleeve.

10. A cable connecter comprising a sleeve provided with longitudinal slits running through one end and approximately to the other end to enable one end of the sleeve to expand to anchor the connecter in a box hole, box hole anchorage means made on the sleeve, a screw mounted in the sleeve adapted to expand the sleeve end aforesaid, a stam ing made with parallel s lits therein, a ca le clamp plate formed between the stamping splits and disposed in alignment with the screw and adapted to be pressed downwardly against a cable by said screw,

means on one end of the plate to movably attach it to one end of the sleeve; and a pair of lining plates integral with the clamp plate and being formed by the aforesaid stamping splits, one lining plate being disposed on each side of the clam plate, adapted to overlap and cover the a oresaid longitudinal slits in the sleeve; and a bushing integral with the stamping at one end thereof through which wires from a cable pass.

In testimony whereof I afiix my signature.

JAMES GAMROD LEDBETTER.

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