US2603680A

US2603680A - Electrical plug connector

Info

Publication number: US2603680A
Application number: US146970A
Authority: US
Inventors: Snyder Henry William
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-03-01
Filing date: 1950-03-01
Publication date: 1952-07-15
Anticipated expiration: 1969-07-15

Description

y 15, 1952 H. w. SNYDER 2,603,680

ELECTRICAL PLUG CONNECTOR Filed March 1, 1950 FIG. 1.

FIG- 6- 2 Fla 1. FIG. 8.

INVENTOR.

' H ETTIH William Engder BY A mas/Q1 ATTORNEYS.

Patented July 15, 1952 I. U NITED STAT-ES PATENT OFFICE v 2,603,680 ELECTRICAL PLUG CONNECTOR 7 "Henry William Snyder, Bzeman, Mont.

Application March 1, 1950, Serial No. 146,970

' 3 Claims.

This invention relates to an-irnprovediorm of electrical plug connector particularly for heavy current carrying flexible cables adaptedfor welding lead conductors and other uses where such plugsmay be employed.

The primary object of this invention is to provide an improved solderless electrical plug connector which may be easily and permanently attached to the end of flexibleorextra flexible electrical cable and provide a connection between cable and plug of low electrical resistance and good 'mechanical strength. -Other solderless type plug connectors either are of the screw type which may loosen-and becomedisassembled or cause heating and arcing among their various parts, or else special tools are required for permanent assembly of .thevariousparts. Among the advantages of this invention are: simplicity of design for ease in manufacture and assembly. Assembly may-be done with only an arbor press end for a suitable-length approximately the length of the clamping sleeve, as shown .in Ei 2. Plug l0 andfsocket H are .preferably made of brass or bronzehaving a high electrical conductivity, such as is usual for electrical plug connectors, and clamping sleeve I2 is preferably M copper tubing having a wall thickness of ap- (or common table vise in an emergency), no

special tools being needed. d

Other objects and advantages will appear to those skilled-in the art from the following description, supplemented by the drawings illustrating highly satisfactory embodiments of the invention, and forming apart of this specification.

:In the drawings:

:Fig. .1.is an exploded side view of the plug conne'ctorrelements in accordance with my invention.

Fig.2.is a side view of the connector elements, with parts in longitudinalse'ction, showing the parts with the end of a-cable upon'which they are to be applied.

Figs. 3 and 4' are similar side views illustrating successive-positions of the elements as the plug member is pressed into position.

Fig. 5 is a similar side view showing the plug member in its final position, and the plug connector elements secured on a flexible cable in accordance with my invention.

Fig. 6 is a leftend view of theplug member.

Fig. '7 is aside view of a modified form of plug member.

Fig. 8 is a'left-end view-of the plugmember shown in Fig. I.

Referring to the drawings wherein similar'referance characters designate corresponding parts throughout the several views, the solderless elsetrical plug connector or cable terminal connector in accordance with my invention consists of three members, aplug H), a shell '0I socket H and a clamp sleeve l2 for application to a flexible. type of cable l3from the end of which insulation [4 hasbeen removed to barethe-cablewires atthe proximatelyone thirty-second inch and suitable inside diameter to slide freelyover the stripped end l5 of cable l3. The copper clamping sleeve is dead-soft vannealedso that .it may be readily crimped or deformed into gripping engagement with the bared wires'at the end H; of the cable.

The shell or socket member I l, at. times hereinafter referred to as a first conductor element is machined or otherwise formed preferably from tube stock, of such dimensionsthat no machining is necessary .on the outside. The tube socket preferably has a bore N5 of such, diameter that the strippedend l5 of cable [3 maybe freely inserted through it without requiring machining operations. Theouterendof the shellor socket l l'has a larger concentricbore ll machined toa close tolerance so that ,a tight fit (otherwise' designated as a. class6 fit) will lee-provided between itand the cylindricalinner end 18' of the plug member. The angle of a bevel -shoulder l9 between bores l6 and i1 .is shown as sixty degrees with respect to the axis of the shell portion, though thisangle may be varied l Plug member [0, at times hereinafter referred to as a second conductor element, ispreferably formed from standard rodstock of the required diameter providing the ,cylindricalportion l8 thereof, as mentioned above, or, it may be formed from other stock and machined so that the cylindrical portion IS with the required diameter is provided. The outerend'lfi may be tapered so as to fit standardplug receptacles andthe inner end is machined to a diameter slightly .less than the inner diameter of clamping sleeve l2 to provide asmall shoulder 20 thereon which facilitates theassembly of the plug connector on .the endof a flexible cable.

While plug Ill provided with theshoulderZfl is preferable and requires inits formation only a simple minor operation in an automatic screw machine which does. not add. appreciably 'to manufacturing costs, the plug 2| shown in Figs. 7 and 8, having a flat end 22, may be .used in place of such a shouldered plug 10. Plug-2]: re: quires less machine work.

Plug l0 as illustrated, and above described, is provided with a tapered plugging end. However it will be understood that any conventionalpform connector upon the end of the flexible or extraflexible electrical cable I23, thefcable end must first be stripped of insulation I II for a suitable length as previously explained. In the drawings this length is shown as being approximately the same as the length of the clamping sleeve [2, but this is a matter of design which will depend upon thelength of bore I6, diameter and length of largeconcentric bore I! of the shell or socket I I, and the wall thickness'of clamping sleeve 12.

I have found that satisfactory proportions of- ;the various parts may be as follows: length of socket element II, approximately six times the diameter of stripped end I5 of the flexible electrical cable; length of bore I6 of the socket,

approximately equal the diameter of the stripped end' I5 of the electricalcable; length of clamping sleeve I2 before deformation, approximately four and one-half times the diameter of the stripped end l5 of the electrical cable; and diameter of large bore I1 of socket I l, approximately one and,

one-half times the diameter of the stripped end I5 of the electrical cable. When these proportionsare'used and the cable stripped as described above,,the stripped end I5 of the cable will extend approximately half way through the larger bore I"! of the socket II when inserted through the smallerbore I6 as shown in Fig. 2 where the portion I is shown inserted intothe outer end of the shell or socket I I in position to engage the clampingsleeve overthe shoulder 20.

With the stripped end I of the cable held in place (by hand or other convenient means) and the-inner end 23 of theshell or socket II sup- .ported by angle brackets or other convenient means, pressure is applied to end surface 24 of the plug) or 2|) bymeans of the plunger ofv an arbor press or other convenient means. Under this pressure the plug Idis' forced into large concentric bore I! of the shell portion and the end surface of. the plug surrounding shoulder 20 engages and applies longitudinal pressure upon the clamping sleeve I2. Under the influence of this longitudinal pressure, the inner end-2 5 of the clamping sleeve is forced against bevel shoulder IQ of the shell or socket II and deformedagainst. the stripped end l5 3. Whenno further'deformation is possible in this direction, the wall of the clamping sleeve I2 4 sleeve until the same is. completely folded and compressed substantially as shown at 21 in Fig. 5, and the stripped end I5 of the flexible electrical cable is clamped in place by means of the radial pressure previously noted and also by the pinching of the cable strands between the folds of the clamping sleeve.

When the pressing operation is completed the plug Hi is firmly gripped within the larger concentric bore I'I of the socket member I I by reason of the tight fit between this larger concentric j bore l7 of the socket andthe cylindrical portion I8 0f the shell or socket ll. As shown in Fig. 5

' both the end of clamping sleeve I2 and frayed ends 2601 the stripped portion I5 of cable I3 are in intimate contact or engagement with the end'of plug I0, which insures a good electrical contact between the wires of the cable and the plug, and tendsto solidify the connection between the socket II and plug .III.

From the foregoing it will be seen that the cable connection illustrated, particularly with a plug connector, has numerous advantages in providing an electrical connection with terminal connecting members, or as the cable terminal connection in other forms of connections for flexible stranded wire cables, and it is to be understood that the invention includes such connections within the scope of the claims.

I claimi 1. A connector for the terminal of an electric cable including a deformable cylindrical tubular clamping sleeve having an internal diameter slightly greater than the bared conductor end of the cable to be inserted thereinto, a first con- 4 nector element having a longitudinal bore therethrough of'a diameter through which the bared conductor end may pass at one end and into the clamping sleeve and of a diameter greater than the sleeve at its other end so that one end 7 of the sleeve may be inserted therein and over the of the flexible electricalcable as shown in Fig.

collapses inward and folds against the stripped end: l5 of the flexible electrical cable, and also against the wall of the larger bore ll of the shell v or socket'l I substantially as shown in Fig and exerts a substantial radial pressure between cable end-l5 and the socket bore. In the process of 1 folding inward,,the clamping sleeve I2 pulls and pinches some strands. of the stripped'end I5 1 1 of the flexible electrical cable I3 causing the." end'to fray substantially as shown at 25 in Fig.

4. Continued pressure upon surface 2 4 of, the plug It) causes repeated folding of the clamping end of the conductor, means on said element for effecting a crimping of said end of the sleeve into the conductor, a second connector element having a cylindrical end portion of a diameter to provide a tight fit in the increased diameter bore of said first connector element, and an extension of reduced diameter on the end of the second connector element for entering the opposite end of the sleeve providing a guide and an abutment so that when this second element is driven into the first element it will compress the sleeve to deform it so as to alternately engage and grip the bared conductor and the surface of the bore so as to lock the parts in assembled relation.

2. A connector for the terminal of an electric cable including a deformable cylindrical tubular clamping sleeve having an internal diameter slightly greater than the bared conductor end of thev cable to be inserted thereinto, a first connector element having a longitudinal bore therethrough of a diameter through which the bared conductor end may pass at one end and into the clamping sleeve and of a diameter greater than the sleeve at its otherend so that the sleeve may be inserted therein and over the end of the conductor, said element having a beveled shoulder at the juncture of the larger smaller "diameters of the bore, tapering from the smaller diameter and providing a forming surface for the clamping sleeve so that upon application of endwise pressure on the sleeve, its end engaging this tapering surface'will be contracted and caused to bite into the bared conductor, and a second connector element having a cylindrical end portion of a diameter to provide a tight fit in the increased diameter bore of said first connector element so that when this second element is driven into.the first element it will compress the sleeve to deform it so as to alternately engage and grip the bared conductor and the surface of the bore so as to lock the parts in assembled relation.

3. A connector for the terminal of an electric cable including a deformable cylindrical tubular clamping sleeve having an internal diameter slightly greater than the bared conductor end of the cable to be inserted thereinto, a first connector element having a longitudinal bore therethrough of a diameter through which the bared v conductor end may pass at one end and into the clamping sleeve and of a diameter greater than the sleeve at its other end so that one end of the sleeve may be inserted therein and over the end of the conductor, and a second connector element having a cylindrical end portion of a diameter to provide a tight fit in the increased diameter bore of said first connector element, an extension of reduced diameter on the end of the second connector element providing an abutment 6 for engaging the end of the conductor which will enter the'end of the sleeve and afford a guide therefor and an annular cavity between the extension and saidlarger bore of the first connector element, said cavity providing a shoulder between the extension and end of the second connector element affording an abutting surface for the opposite end of the sleeve so that when this second element is driven into the first element it will compress the sleeve to deform it so asto'alternately engage and grip the bared conductor and the surface of the bore so'as to lock the parts in assembled relation.

HENRY WILLIAM SNYDER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,643,110 Briggs Sept. 20, 1927 2,076,072 Douglas Apr. 6, 1937 2,394,020 Soreny Feb. 5, 1946