US 2770791 A
Description (OCR text may contain errors)
Nov- 1 1956 H. w. BATCHELLER 2,770,791
ELECTRIC CONNECTOR MEMBER WITH OPPOSED BOTTOM FLAPS Filed Jan. 28, 1954 v Q I l United States Patent ELECTRIC CONNECTOR MEMBER WITH OPPOSED BOTTOM FLAPS Hugh W. Batcheller, Newton, Mass., assignor to Kent Mfg. Corp., Newton, Mass., a corporation of Massachusetts Application January 28, 1954, Serial No. 406,837
Claims. (Cl. 339-258) This invention relates to electric connectors of the male and female type, and more particularly to an improved female member adapted to cooperate with a male connector member consisting essentially of a plane tongue. Female connector members of this type are usually in the form of a shallow channel having a floor, side walls and overhanging flanges, together with some means by which a male member assembled with the female member is subjected to pressure for the purpose of ensuring a good electrical connection and also to prevent accidental disconnection. In the highly competitive market for connectors of this type which has developed, such connectors being widely used in the wiring of various kinds of electrical apparatus such as radios, electric ranges and electric refrigerators, certain characteristics are required for a successful commercial connector. The members must be capable of being easily and inexpensively manufactured in large numbers and of uniform quality. The members must be easy to connect but not too easy to disconnect. When connected, the members must have mutually engaged areas which are strongly pressed to provide a good electrical connection of low resistance. The connector must be capable of many connections and disconnections and also rough usage without any noticeable deterioration in its performance as an electrical connector.
Since connectors of this type are commercially made by the million, it is not feasible to provide members with the optically plane broad surfaces for interfacial contact as would be necessary to approximate the theoretical maximum conductivity of the interfaces. Hence, when broad faces of connector members are pressed together, the areas of actual contact are limited by the tiny surface irregularities on such faces.
The connector embodying the present invention is especially superior in the matter of area and pressure of interfacial contact between the members of the connector. As hereinafter described, the female member, which embodies the invention, has four edges of substantial length which rub lengthwise on the faces of the male member of the connector when the latter is introduced into the female member. As these edges are pressed against the broad faces of the male member, they smooth and polish the areas of mutual contact and provide a low-resistance electrical connection.
For a more complete understanding of the invention reference may be had to the following description thereof and to the drawing, of which Figure 1 is a plan view of a female connector member embodying the invention;
Figure 2 is a plan View of a conventional male member adapted to join with the member shown in Figure 1;
Figure 3 is a section on the line 3-3 of Figure 1;
Figure 4 is a section on the line 4-4 of Figure 1;
Figure 5 is a fragmentary plan view of a blank for a connector member like the one shown in Figure 1;
Figure 6 is a section on the line 6-6 of Figure 5;
Figure 7 is a section similar to Figure 6, but indicating successive steps of bending the blank;
Figure 8 is a plan view of an assembled connector; and
Figure 9 is a section on the line 9-9 of Figure 8.
A female connector member embodying the invention can be made by cutting out a suitable blank 10 from a sheet or strip of metal such as brass or bronze which has suflicient strength and resilience. The'blank 10 is made with two lateral flaps 12 and 14 which are preferably of trapezoidal shape. An H-shaped slot is cut in the middle of the blank, this slot consisting of a straight slot 16 on the longitudinal median of the blank and transverse slots 18 and 20 which extend from each end of the slot 16 to form the H. The slots 18 and 20 make obtuse angles with each other so that the H defines two flaps 22 and 24 which are trapezoidal in shape and are preferably similar in size and shape to the flaps 12 and 14. The sides of the blank are bent up at right angles to the central portion along lines of bend tangent to the ends of the H slot, as indicated in Figure 7. The flaps 12 and 14 are then bent inward so as to extend toward each other and to incline slightly downward toward their free ends. The lower flaps 22 and 24 are bent slightly to incline upward from the plane of the floor 26 toward their free ends. In the sample illustrated on the drawing, the lower flaps 22 and 24 underlie the upper flaps 12 and 14 and are of similar size and shape. The inclination of the flaps causes the flaps 12 and 22 to converge toward their free ends which thus present right-angled edges 28, 30, 32 and 34 for engagement by a male connector member to be thrust in between the upper and lower flaps. Similarly the flaps 14 and 24 converge toward their free ends, as indicated in Figures 3 and 4. The side walls 40 and 42 which rise from the sides of the floor 26 are of such height as to provide clearance at the walls for the reception of a male connector member having a flat rectangular tongue 44 adapted to be thrust into the channel of the female member. The inclination of the four flaps is such that the clearance between the free end edges of the upper and lower flaps is less than the thickness of the tongue 44. The edges of the flaps which are nearest to the receiving end of the connector member are inclined from the side walls toward the median of the member in directions diverging from said receiving end. When the tongue is thrust into the channel, the leading edge of the tongue first engages the flaps at points near the side walls and then rides along the adjacent side edges of the flaps so as to spring the flaps away from each other sufiiciently to admit the tongue between the end edges of the upper and lower flaps. This distortion of all the flaps causes the four end edges thereof to bear strongly against the faces of the tongue and to rub longitudinally thereon as the tongue is pushed in. This results in a smoothing and polishing of the relatively narrow areas of mutual contact to something approximating a ground joint so that a low-resistance connection is obtained.
Figures 8 and 9 show the two members of the connector joined together. While the frictional engagement of the four edges of the flaps of the female member with the tongue of the male member will usually be sufficient to hold the members together against accidental separation, additional holding means may be provided such as bosses 50 on one or more of the flaps which enter dimples or holes 52 in the tongue 44 when the members are joined.
1. An electric connector member comprising a piece of sheet metal bent to form a shallow channel with a floor, parallel side walls, and upper flaps projecting from said side walls over said fioor toward each other, said flaps sloping slightly downward toward their face ends, and slots in said floor forming lower flaps underlying said 9 A a upper flaps and sloping slightly upward toward their free stantial length and is parallel to the end edges of the other ends. flaps.
2. A connector member as in claim 1, all of said flaps 5. A connector member as in claim 4, each of said end being of substantially the same shape. edges being near the median of the member.
3. A connector member as in claim 1, the edges of the 5 flaps which are nearest to the receiving end of the con References Clted m the file of thls Patent nector member being inclined from the side walls in UNITED STATES PATENTS directions diverging from said receiving end. 1,995,115 Douglas Mar. 19, 1935 4. A connector member as in claim 1, the free end Of 2,579,739 Hayes Dec. 25, 1951 each said flap having a straight edge which is of sub 10 2,600,190 Batcheller June 10, 1952