US2495623A

US2495623A - Plug connector

Info

Publication number: US2495623A
Application number: US5413A
Authority: US
Inventors: George B Benander
Original assignee: MONOWATT Inc
Current assignee: MONOWATT Inc
Priority date: 1948-01-30
Filing date: 1948-01-30
Publication date: 1950-01-24
Anticipated expiration: 1967-01-24

Description

HIF.R .M

Inventor-z George B.Be nander;

G. B. BENANDER PLUG CONNECTOR Jan, 24, 1951) Filed Jan. 30, 1948 atented Jan. 24, 1950 PLUG CONNECTOR George B. Benander, Oaklawn, R. I., assig'nor to Monowatt Incorporated, a corporation of Connecticut Application January 30, 1948, Serial N 0. 5,413 1 Claim. (Cl. 173-361) The present invention relates to plug connectors such as are used to connect an electric cord to a convenience outlet or receptacle.

The object of the invention is to provide an improved connector which is simple in structure, comprises a minimum number of parts, and is capable of being manufactured and assembled on a cord at low cost.

A further object of the invention is to provide an improved construction wherein the cord may extend from the connector either parallel to the contact blades or at an angle thereto.

A further object is to provide a construction wherein the wires of the cord are connected firmly to the blades without the use of screws and wherein the cord is held in a manner such as to provide a good strain-relief for the connections.

Other objects and the advantages of the invention will be apparent from the following specification.

For a consideration of what I believe to be novel and my invention, attention is directed to the following specification and to the claim appended thereto.

In the drawing, Fig. 1 is an exploded perspec tive view of the parts forming my improved plug connector, a cord end with the wires bared being shown adjacent the contact blades; Fig. 2 is a perspective view illustrating a plug connector partially assembled on a cord end; Fig. 3 is a transverse sectional view of the structure as shown in Fig. 2; Fig. 4 is a sectional view of the connector body; Fig. 5 is a plan view of a completely assembled connector attached to a cord end; Fig. 6 is a perspective view of a connector with a cord attached thereto; Fig. '7 is a side view of the connector, and Figs. 8 and 9 are views showing modifications.

My invention is well adapted for use with fiat two-conductor cords wherein the two conductors are parallel (one type of such cord being known in the trade as POSJ) and I have elected to illustrate my invention embodied in a structure for use with such cord. It is to be understood, however, that the invention is not limited to use with such cord, it being adapted also for use with other types.

Referring to the drawing, Figs. 1 to 7, I indicates the body of the connector, 2 indicates the two contact blades, and 3 indicates an electric cord, the bared ends of the conductors of the cord being indicated at 4.

The body which may be formed from a suitable molding compound is generally rectangular in outline, although it may be of other shape. Its walls define a central recess or cavity 5 which extends substantially to what may be termed the lower end of the connector, the bottom wall being indicated at B; on each side of the central recess a pair of vertically extending grooves I; and at an intermediate point a pair of ledges or shoulders 8. Grooves 1 are adapted to receive the inner ends 2a of contact blades 2. The grooves I, in what may be termed for purposes of description, the front wall 9 of the body, extend to the open side III of the body. The grooves I, in what may be termed the rear wall II of the body, terminate at the surface of ledges or shoulders 8 (see Fig. 4). The inner side of rear wall II is shaped to define depressions or grooves I2 which are opposite the outer ends of the grooves i which are in front wall 9. In front wall 9 is a slot I3 which, at its lower to form a rounded opening I4. Slot I3 and opening I4 form an open ended keyhole slot in the side wall of body I. Slot I3 is of a width about equal to the narrow width of cord 3. Rounded portion I4 is of a width equal to the wider dimension of cord 3. In wall 9 below opening It is a groove I5 of a size to receive a cord 3.

Contact blades 2 are provided on the side edges with serrations or teeth I6 WhlCh, when the blades are inserted in grooves I bite into the end walls of the grooves to grip the blades and hold them firmly in place. the inner ends of the contact blades are openings II. Each contact blade, on what may be termed its outer side, is provided with a clamping eye I8 adapted to clamp the bared end of a conductor. The clamping eyes I8 may be formed from material of the blades. In the present instance, the contact blades are shown as being formed from a strip of suitable metal bent back upon itself and clamping eyes I8 are formed from metal of the outer strip piece, being formed from the material struck out to form openings I1. Thus, the clamping eyes I8 are at the upper ends of the openings I1. In the side edges of blades 2,.just above the teeth I6 are curved recesses I9. In the assembled plug, these recesses lie just above the ledges or shoulders 8. In the end walls of body I, are vertical grooves 20 of a Width about equal to the width of eyes I8 and in which the eyes are located.

In assembling the connector on a cord end, the bared conductor ends 4 are threaded into the eyes I8, after which the inner ends of the contact blades are forced down into the grooves I. This may be done in a suitable fixture, the base I being suported in the stationary bed of a fixture, for example, and the contacts 2 being carried by a movable part of the fixture which can be lowered either manually or by suitable power means to force the inner ends of the blades along the grooves I. As the contact blades are reaching the inner end of their movement, the lower walls of the eyes strike ledges or shoulders 8 and are forced upward to close somewhat the eyes and squeeze the conductor ends between the walls 01 the eyes as shown particularly in Fig. 3. Thus. by the act of inserting the inner ends of the contact blades into position in the body l, the.-

conductor ends are automatically tightly con-- nected thereto. Assembled thus far, the cord extends in the direction as shown in Figs. 2 and 3',-

the two wires of the cord being positioned at the outer sides of blades 3. Next, the cord is brought across the face 10 of; the base between the blades 2, the two wires or? the cord being, thus passed around the rear edges of the blades; and

they are pulled down into the spaces formed. by

grooves [2 in body I and recesses [9 in blades 2, as shown particularly in Fig. 5. These spaces are of a size such that the wires are tightly wedged therein. The cord is then given a quarter-turn. twist So that it maybe passed edgewise downthrough slot I-3, and-- after being passed down. through slot !3, it is: twisted back again to occupy the rounded recess M. The cord may extend at-i an angle, such as at a right angle, to' the. con nector as shown in full lines in Fig.6, or. it may extend in a direction parallel to" the blades as indicated in dotted lines in Fig. 6, it then beingv positioned in groove 15- so it is substantially flush:

for attaching a conductor" end. to the blade. In: Fig. 8, I have shown anarrangement wherein the? contact blade 2t is provided with an car 22 and:-

a terminal screw 23 for-use: inattaching a con ductor end to the blade, instead. of the eye 18-.-

Otherwise, the construction. may be that of Figs;

1 to '7; and in Fig. 9, an arrangement wherein. the contact blade 24 is provided with a projecting ear 25 which fits into. a recess 26 ina ledgeor shoulder 21 corresponding. to ledge 01'' shoulder 8 of Figs 1 to 7, the conductor end 28 being A,

clamped between ear 25 andhthe walls 'of recess- 26 as clearly shown in Fig. 9.

By my invention, it will be seen-that I pi0'-- vide a connector which. comprises only a single piece body and two contact blades; a connectorwhich can be quickly and easily assembled on a cord end; a connector wherein a good strainrelief is provided for the terminal-connections:

and a connector wherein the cord may extendeither at an angle to the c'onnector'or in a line" parallel to the contact: blades What I claim as new and. desire to secure-by Letters Patent oi the United. States is:

A plug connector for use with a flat two-conductor cord comprising a body of hard rigid material having a longitudinally extending cen: tral recess and an open-ended Keyhole slot oe'n trally disposed in its side wall and communicating with said recess; a pair of transversely 0pp'osed longitudinally extending grooves in the sidewalls of said recess, one pair of grooves being on each side of said slot; a pair of fiat contact blades fixed to the body with one blade in each pair of grooves, said blades having their outer surfaces and their edges which are removed from said slot spaced from the adjacent walls of the recess by an amount not greater than the thicknessof' a single insulated conductor which. is to be secured in said space; and means for attaching bared conductor ends to said blades at theouter sides of the blades, said means including shoulders formed in the body and extending, inwardly from both end walls of said recess and reversely bent tongues lanced from: said blades extending from the outer sides there-- or and adapted to grip said bared conductor ends: wherrsaid blades-are forced into said grooves with said. tongues resting on said shoulders; said keyhole slot having an entrance portion of a" width not substantially greaterthan the narrow width. of the cord and an enlarged bottom aportion. of a width substantially equal to the side width of the cord; whereby the said fiat two conductor cord, after having its bared conductorends attachedv to the blades on the outer sides, may have the separated single insulated.

conductor ends wedged into the spaces between the blades and the body and. may have the" joined. conductor cord passed between the blades and thence edgewise through the entrance portion of said; slot, and there be turned to occupy the en- .larged. b-ottorni portion thereof.'

GEORGE E. BENANDER.

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

UNITED STATES PATENTS Number Name Date 849,934i Thomas Apr. 9, 1907 1,696,495 Malling Dec; 25', 1928 1 ,729,740 Gaynor Oct. 1, 1929; 1,751,842 Propp Mar. 25, 193,) 1,780,851 Strongson NOV. 4, 193 1,92',806 Benander Feb. 26, 193 216%,847 Clark, Jr; Aug. 13, 1935 2,015,421 Eckstein et al Sept. 24, 1935 2,027,447 Percy Jan. 14, 1936' 2,115,642 Martin Apr. 26, 1938 2,182,446 Nelson Dec. 5, 1939 2,236,764 Peterson Apr. 1, 1941 2,316,072 Judisch Apr. 6, 1943 2,429,273 Roche Oct. 21, 1947