US3144506A

US3144506A - Insulating cover for connectors having tapered cable entrances

Info

Publication number: US3144506A
Application number: US44319A
Authority: US
Inventors: Jr Alfred B Gunthel
Original assignee: DOSSERT Manufacturing CORP
Current assignee: DOSSERT Manufacturing CORP
Priority date: 1960-07-21
Filing date: 1960-07-21
Publication date: 1964-08-11
Anticipated expiration: 1981-08-11

Description

Aug- 1964 A. B. GUNTHEL, JR

INSULATING CON/ER FOR CONNECTORS HAVING TAPERED CABLE ENTRANCES Filed July 21, 1960 2 Sheets-Sheet 1 INVENTOR ,4; F/PED 3. Gu/vr/m J2.

ATTORNEYS A. B. GUNTHEL, JR

Aug. 11, 1964 INSULATING COVER FOR CONNECTORS HAVING TAPERED CABLE ENTRANCES Filed July 21, 1960 2 Sheets-Sheet 2 INVENTOR AQFPE'D 5. g'wvvv/EL J/e.

BY W g 7442 TTORNEYS United States Patent 3,144,506 INSULATHN'G COVER FUR CONNECTORS HAVING TAPERED CABLE ENTRANQES Alfred B. Gunthel, Jr., Sea Cliff, N.Y., assignor to Dessert Manufacturing Corp., Brooklyn, N.Y., a corporation of New York Filed July 21, 1960, Ser. No. 44,319 5 Claims. (Cl. 174-71) This invention relates in general to electrical connectors and to an improved insulation cover therefor, and particularly to a new and useful multiple cable connector having means for clamping together and electrlcally connecting cables of different diameters with uniform clamping pressure.

The present application is a continuation-in-part of applicants prior co-pending application Serial No. 26,503, filed May 3, 1960, now abandoned.

The present invention is particularly applicable for the electrical connection of conductor members or cables of a wide range of sizes. With previous electrical connectors of this type, diificulty was encountered with providing a connector member which could be readily secured to the cables and which could be clamped in a manner to inmodate the particular cable sizes being used.

In accordance with the present invention, there is provided a combination novel electrical connector assembly which is adapted to be fitted into an insulation cover member having a hinged cover portion with tapered openings arranged to accommodate cables of various diameter sizes. The electrical connector and clamping element includes a connector body which includes at least two cable receiving grooves of a radius generally conforming to the radius of the cable to be received therein. Cables are first stripped of their insulations and placed in the grooves of the connector body and are held therein by a cable clamping cap having a similar number of grooves and having a curved outer face which is aligned by a tangential pressure plate which is bolted to the connective body by means of a bolt which extends through the pressure plate and cap and is secured against the pressure plate with uniform pressure by means of a dish-shaped washer. The arrangement is such that the pressure plate possesses a concave true are which matches the convex true are of the cable clamping cap in order to provide a flat pressure area perpendicular to the axis of the bolt irrespective of the position or attitude of the clamping cap. Thus the clamping cap may be aligned to bear evenly on each of the cables regardless of the relative diameters of each and the tangential pressure plate adjusted to insure that each of the cables is held with a uniform securing force. The connector body is provided with cable receiving grooves which are of suflicient extent to wrap around a substantial portion of the conductor or cable in order to provide as great a radial angle of contact as possible and to conduct a major portion of the current from one cable to the other. The dish-shaped washer is elfective to maintain a constant clamping preseach end of the member and a single tapered groove on 3,144,506 Patented Aug. 11, 1964 ice one side thereof which is split in half at the mating of the top cover and the bottom portion, so that the top cover may be hinged to an open position and the cables positioned in the grooves of the body'member of the connector. A feature of the cover member construction is that the tapered openings at each end of the member are such that the minimum diameter thereof will accommodate a range of cable sizes which have been stripped of their insulation. The outer diameter portion of these openings is large enough to accommodate the largest expected cable size with the insulation thereon. Thus to position a cable in the connector and the cover member, it is merely necessary to strip the insulation from the cable only between points which will permit the insulation remaining on each end of the cable to abut tightly against the walls of the opening. In this manner, the insulation of the cable itself forms a seal with the tapered walls of the opening of the cover member.

It is an object of this invention to provide an improved electrical connector.

A further object of the invention is to provide an electrical connector including a conductive body member having at least two cable receiving grooves, a conductive cable clamping cap adapted to fit over each of the cables in the groove, and a tangential pressure plate member having the same interior curvature as the outside curvature of the cap member adapted to be clamped to the body portion of the connector to hold cables in the grooves of the body portion with equal clamping pressure regardless of the relative sizes of the cables.

A further object of the invention is to provide a combination insulation cover and electrical connector including clamping means adapted to be fitted into the cover to secure a cable therein, and including a tapered opening defined in the cover having a minimum diameter at least as large as the largest sized cable without insulation to be secured therein, and an outer diameter at least as large as the largest sized cable with insulation covering thereon.

A further object of the invention is to provide an improved insulation cover member for an electrical connector including separable bottom and top portions defining together at least one tapered opening for receiving an uncovered cable through the smaller sized portion of the opening and for permitting wedging of the covering of said cable in the opening between the smallest andlargest diameter portions thereof.

A further object of the invention is to provide an improved electrical connector including a body portion having two parallel grooves defined therein, and a U-shaped cable clamping cap member including groove portions adapted to overlie the groove portions of said body member to hold a cable positioned in said groove, and a tangential pressure plate member adapted to conform to the configuration of the exterior of said lU-shaped cable clamping cap to hold the latter against said cables with uniform clamping pressure.

A further object of the invention is to provide an electrical connector and an insulation cover member which are simple in design and rugged in construction, and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects obtained by its use, reference should be had to the accompanying drawing and descriptive matter in which there is illustrated and described a preferred embodiment of the invention. 7

In the drawings:

FIG. 1 is an exploded perspective view of a combination electrical connector and insulation cover member constructed in accordance with the invention;

FIG. 2 is a fragmentary top plan, partly broken away, of the combination electrical connector and insulation cover member;

FIG. 3 is a section taken along line 3-3 of FIG. 2; and

FIG. 4 is a transverse section through the electrical connector member with cables of ditferent diameters clamped in position.

Referring to the drawings in particular the invention embodied therein includes an enclosing cover member generally designated A and an electrically conductive electrical connector or clamping member generally designated B.

In accordance with the invention, the cover member A includes a lower shell or bottom portion and an upper shell or top portion 12 which is hingedly connected to the bottom portion by means of

hinge arms

14 and 16 which include pivots 18 to engage apertures on

arms

17 and 19 of the top portion 12. The upper portion 12 exactly complements the lower portion 10 and the portions are provided with tongue and groove seals 20 around their mating peripheries in order to insure a tight fit. When the upper portion 12-is in position'overlying the bottom portion 10,

the parts are locked together by a pair of resilient tab members 22. The tab members 22 form a downward extension of the upper portion 12 and they are deflected outwardly by an outstanding abutment 24 of the lower portion 10 so that the outstanding portion can be wedged into an opening 26 formed on each tab 22.

In the present embodiment of the invention, the cover member A and the electrical connector B are constructed to provide means for accommodating one through cable generally designated 28 and a single branch or connecting cable generally designated 30 (FIG. 2) which is to be electrically connected to the through cable. It should be appreciated that a greater number of cables could be connected in the same manner without departing from the principles of the invention.

To accommodate the main or through cable 28 the upper portion 12 and the lower portion 10 are provided with aligned complementary

tapered openings

32 and 34 on each end. The connecting cable 30 is accommodated in a single tapered opening 35. The openings 3234 and 35 align with grooves of the electrical connector which accommodate the

respective cables

28 and 30. In accordance with the invention, the openings 3234 and 35 are sized so that the diameter at the interior is made just large enough to accommodate the largest normal size of the central conductive portion 36 of the respective cable which would normally be handled by such a connector. The exterior diameters of each of the

openings

32 and 34 are made slightly larger than the normal maximum diameter of the

cables

28 or 30 with the insulation coverings thereon. Thus, whena main cable 28 is positioned in the cover, it is stripped of covering or insulation between a length which will insure that the covering portions on each side of this length will be wedged into the

openings

32 and 34 when the cable is positioned to extend through the openings of the cover member A. This insures that a tight seal will be provided between the cover and the cable.

The electrical connector or clamping member B comprises a connector body or cable receiving member generally designated 38 having parallel

cable receiving grooves

40 and 42 defined on an inner face thereof, each having a radius of curvature to accommodate the normally expected cable size or range of cable sizes to be rereceived therein. The outer ends of the connector body 38 are turned downwardly so that the conductive metal portion thereof wraps around the conductor which is positioned within the groove to achieve as great a radial angle of contact as possible in order to conduct the major portion of current from one cable to the other.

Each of the

cables

28 and 30 is held tightly in place by a substantially U-shaped cable clamping cap or member generally designated 44? which includes concave or grooved ends which fit flush against the cables positioned in the grooves of the connector body.

In accordance with the invention, in order to provide a uniform clamping pressure on each of the cables 28 and 3t), regardless of their relative sizes the clamping cap 44 is provided with a curved exterior face 46 of the same curvature as an interior face of a tangential pressure plate or member 48. Both the cable clamping cap 44 and the tangential pressure plate 48 are provided with spaced slotted openings to accommodate clamping bolts '50 which contain exterior threads for threading into threaded openings on the body member 38. Between the head of the bolts 5t and the tangential pressure plate 48 is positioned a dish-shaped washer 52 and the bolt 50 is tightened down until the washer is put under downward collapsing pressure between the bolt head and the tangential pressure member 48.

With the construction just described, the tangential pressure plate or member 48 may be aligned with the U-shaped cable clamping cap 44 regardless of the attitude or disposition of the cap afterthe latter has been placed in tight engagement with the cables in the

grooves

40 and 42. Thus, when the bolt 56 is tightened, the tangential pressure plate 48 applies uniform pressure on the cable clamping cap 44 and this uniform pressure is distributed evenly to the

cables

28 and 30.

The electrical connector or clamp B may be made in a wide range of conductor sizes by merely changing the selected radii of curvature of the grooves 443 and 42. In such a manner, numerous combinations of cables can be clamped within this connector with the assurance of a secure mechanical as well as an excellent electrical connection. The

cable holding grooves

40 and 42 on each side of the clamping bolts are so designed that either two maximum sized cables or two minimum sized cables can be securely clamped within the connector, or any intermediate combination of equal sizes of cable from minimum to maximum size, or any combination of unequal sizes of cable within the prescribed range.

In FIG. 4,

cables

54 and 56 of different diameter are positioned in alignment with

grooves

40 and 42 and the clamping cap 44 is cocked to one side in equal securing pressure engagement with each cable.

The connector B may advantageously be made of either a copper alloy or an aluminum alloy possessing relatively high electrical conductivity as well as high physical strength. The construction permits manufacture thereof in the form of a casing, extrusion, or forging, if desired.

To assemble the cable in the connector, in some instances it is preferable that the body portion 38 be made so that it may be separated from the cover member A and the cable stripped and mechanically clamped exteriorly of the cover A. On the other hand, the body portion 38 may be advantageously secured to the lower portion 10 of the cover member A and the upper portion 12 flipped open after deflecting the holding tab 22 outwardly. Thereafter the main cable 28 may be aligned between the

openings

32 and 34 on each end of the cover member and the covering or insulation stripped from the cable to a length which will insure that the remaining insulation of the cable will be wedged in the

openings

32 and 34. In a similar manner the branch cable 30 may be positioned in the opening 35 after it has been first stripped of insulation in an amount suificient to permit the uncovered conductive end thereof to be positioned along the complete length of the groove 40 while insuring that the remaining covering on the cable will wedge in the opening 35. Thereafter, the cap 44, the tangential pressure plate 48 and the washer 52 and the bolt 50 are secured to the body member 38 and the upper portion 12 of the cover member A is closed.

It should be appreciated that one or more clamping bolts 50 may be employed to effect adequate clamping pressure from both the mechanical and electrical standpoints for each of the

cables

28 and 38. Such bolt or bolts 54) may advantageously be made of a high strength bronze alloy, aluminum alloy or steel alloy suitably plated for protection against corrosion. The washer member 52 is advantageously made of a resilient bronze, copper or alloy steel material suitably plated for protection against corrosion, and provides a means for obtaining a constant clamping pressure on the tangential plate member 48 irrespective of slight changes between the relative sizes of parts which would occur within the connector due, for example, to thermal changes, creep, or flow in theconductors, etc.

It should be appreciated that the cover member tapered openings insure a reasonably tight closure between the cover member A and the cables 2.8 and 30 which are to be positioned in the unit. The tapered apertures are designed to receive the minimum cable size inclusive of its insulation through the minimum diameter of the opening. As the cable sizes to be introduced become larger, the cable insulation is stripped back to further extend to a position where the insulation makes its closest contact with the tapered aperature and is wedged in such position. The cover member is advantageously of a high dielectric, high strength plastic material of suflicient resilience to be capable of establishing a self contained hinge and locking tab.

The dish-shaped washers of the electrical connector B perform two important functions. One of the functions is to distribute the bolt pressure from the bolt 50 over a wide flat area and the second function is to permit slight relative movements of the clamping portions of the member due to stressing of the parts such as would occur by excessive heating. The washer 52 is of sufficient concavity to permit it to give slightly under stress. The washer 52 transmits its bearing force over a wide area on the flat side of the tangential plate 48. Such a construction avoids line contact as well as concentrated clamping pressure and eventual relaxation of the clamp due to metal flow caused by excessive bearing stress.

The tangential pressure plate 48 receives its clamping force from the spring washer over its wide area of distribution and in turn transmits its pressure over a wide arc area to the connector cap.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the invention principles, it will be understood that the invention may be embodied otherwise Without departing from such principles.

What is claimed is:

1. A cover member for a connector adapted to electrically connect uninsulated portions of adjacent insulated cables comprising complementary upper and lower enclosing shells hingedly connected together, said shells having outwardly tapered conical troughs defining together at least two cable receiving openings, said tapered troughs being of an exterior maximum dimension slightly larger than the cable diameter with its insulation, and an inner dimension slightly larger than said cable stripped of its insulation and being spaced a fixed predetermined amount so that upon closure of the hinged upper and lower shells the conical troughs form a moistureproof seal with similarly shaped conical terminal portions of the insulation about the cables.

2. A cover member according to claim 1, wherein said cover member is made of flexible plastic and includes locking tab means on one of said shells engageable with projection means on the other of said shells.

3. A cover member according to claim 2, wherein the abutting surfaces of said upper and lower shells are provided with tongue and groove seal means.

4. A cover adapted to enclose a line tap connector of the type securing a branch conductor in electrical connection with an uninsulated portion of an insulated continuous line conductor comprising, complementary upper and lower enclosing shells of insulating material, said shells having substantially rectangular mating edge portions, hinge means connecting said shells along an axis substantially parallel with one of said edge portions, 21 first pair of complementary outwardly tapered conical troughs in an edge portion of said shells adjacent said hinge means edge portion, a second pair and a third pair of complementary outwardly tapered conical troughs in the edge portion opposite said first pair of conical troughs, said second pair of conical troughs being in axial alignment with said first pair, each of said pairs of troughs forming a cable receiving opening having an inner minimum dimension slightly in excess of the dimension of the conductors when stripped of their insulation.

5. The combination comprising a continuous insulated line conductor having a short uninsulated portion intermediate the length thereof, an insulated branch conductor having an uninsulated end portion connected to the uninsulated portion of said line conductor, the insulation being formed so as to terminate as a cone about the uninsulated portion of each conductor, a cover enclosing the uninsulated portions of said line conductor and said branch conductor, said cover including complementary upper and lower enclosing shells of insulating material, said shells having substantially rectangular mating edge portions, hinge means connecting said shells along an axis substantially parallel with said line conductor, a first pair of complementary outwardly tapered conical troughs in an edge portion of said shells adjacent said hinge means, a second pair and a third pair of complementary outwardly tapered conical troughs in the edge portion opposite said first pair of conical troughs, said second pair of conical troughs being in axial alignment with said first pair, each of said pairs of troughs forming a receiving opening for engagement with the conical terminations of the insulation about the line and branch conductors and having an inner minimum dimension slightly in excess of the dimension of the conductors when stripped of their insulation.

References Cited in the file of this patent UNITED STATES PATENTS 2,089,856 Reynolds Aug. 10, 1937 2,651,766 Runde Sept. 8, 1953 2,658,184 Greenbaum Nov. 3, 1953 2,774,810 Ritter Dec. 18, 1956 2,875,266 Fredericks Feb. 24, 1959 2,894,056 Bogese July 7, 1959 2,898,573 Lamb Aug. 4, 1959 2,927,955 Crawford Mar. 8, 1960 FOREIGN PATENTS 767,333 Great Britain Jan. 30, 1957 775,997 Great Britain May 29, 1957 816,918 Great Britain July 22, 1959 867,790 France Sept. 1, 1941 214,706 Australia May 1, 1958 174,965 Austria May 26, 1953