US 3185953 A
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Description (OCR text may contain errors)
May 25, 1965 J. s. PRlFoGLE 3,185,953"v CONNECTOR Filed Sept. 16, 1963 United States Patent O 3,185,953 CNNEC'IR .lolm' Stanley Prifogle, New Garden Township, Wayne County, Ind., assigner to Belden Manufacturing Cornpany, Chicago, lll., a corporation of Illinois Filed Sept. 16, 1963, Ser. No. 309,063 2 Claims. (Cl. 339-59) This invention relates generally to an electrical connector and, more particularly to an electrical connector having a sheet metal contact.
Ordinarily, for reasons of cost, one or more of the female contacts of an electrical connector is made from sheet metal. Some of such contacts are tubular and, by virtue of their design, they may be formed with a longitudinal seam where the edges of the metal meet. In use, the sheet metal contact has a tendency to spread and deform due to the manner in which the plug is withdrawn from the connector. When this is done with excessive leverage the mouth of the contact may be permanently damaged, resulting in an unreliable electrical connection.
The present invention has for its principal object the provision of a new and improved female connector having a plurality of sheet metal contacts encased within a flexible body. A related object is provision of a polarized connector having a yieldable body with rigid barrier means effectively preventing improper engagement between connector contacts and non-associated plug contacts. Another related object is provision of a connector of more durable and less expensive construction than has heretofore been employed.
Other objects and advantages of the present invention will be understood by reference to the following description and to the accompanying drawings of one selected embodiment.
In the drawings:
FIGURE 1 is a fragmentary perspective view illustrating a female connector embodying various of the features of the present invention;
FIGURE 2 is a fragmentary sectional view taken generally along the line 2 2 in FIGURE 1;
FIGURE 3 is a fragmentary sectional view taken generally along the line 3 3 in FIGURE 1;
FIGURE 4 is a sectional view taken generally along the line 4 4 in FIGURE 3;
FIGURE 5 is an enlarged, fragmentary sectional view taken generally along the line 5 5 in FIGURE 4; and
FIGURE 6 is a fragmentary sectional View taken generally along the line 6 6 in FIGURE 5.
As illustrated generally in FIGURE 1, the invention is, in brief, directed to a connector Il) having a relatively soft and yieldable dielectric body I2 disposed about the end of an electrical cord 14. The selected embodiment is illustrated in the form of a polarized connector generally referred to in the electrical industry as a NEMA connector and is suitably designed and dimensioned to conform to the standards relating to connectors as published by Underwriters Laboratories, Inc. As will be mode fully described, the body 12 has an end face 16 with a plurality of `bores or access openings 20, 22 and 24 which extend from the face toward female contacts (FIGURES 2 and 3) within the connector body 12 and through which access may be had between the interior female contacts and respectively associated male contacts of a complementary polarized male plug (not shown). Extending within the body l2 and across the openings 2li, 22 and 24, just inwardly of the end face 16, is a barrier or insert 28 of a relatively rigid dielectric material. The barrier has passages 30, 32 and 34 aligned with the openings 2), 22 and 24, and with associated female contact members, as 40, 42 and 44, respectively, for access of the male contacts to the associated female contacts. The rigidity of the barrier 28 and the shape and size of the openings Sil and 32 with respect to the associated male contacts effectively prevent forceable entry of a non-associated male contact having a greater cross-sectional dimension than the passage, into engagement with the female contact associated with the passage. The passage 34 receives an outer end or mouth of the female Contact 44, which is of generally tubular construction and of noncircular cross-section, and the barrier 28 closely encircles the mouth for effectively preventing distortion thereof as might occur upon prying movement of the associated male contact.
The connector disclosed herein is designed to receive a complementary polarized male plug having three male contacts, including circular or non-circular grounding contact and a pair of parallel, spaced apart rectangular blades which are of equal thickness but of slightly different widths. However, the disclosed connector may be designed for use with a conventional non-polarized male plug. In this respect, the spacing contemplated between the parallel blades of the complementary polarized plug is identical to the spacing employed between the twin blades of the conventional non-polarized plug, and the contemplate size of the smaller polarized rectangular blade is at least as large as the twin blades of the conventional plug. In this fashion, the blades of the conventional male plug, which may be of lesser width than the polarized blades, will readily enter the inlet openings. In addition, the disclosed connector may receive a polarized male plug having a grounding prong of circular or non-circular cross-section and a pair of twin rectangular blades of a design similar to that employed in the conventional non-polarized male plug.
Although the present invention has been briefly described and will be more fully described in terms of the polarized connector illustrated in FIGURE 1, it should be apparent that this invention is applicable to numerous variations in the number and arrangements of female `contacts employed. In this connection, the female connector may be constructed to receive one or more male contacts in various different patterns or arrangement. In addition, the connector may provide for the receipt of male contacts of a wide variety of different cross-sections as may seem most desirable under the circumstances. For example, the female connector may be a business machine connector, television connector, etc.
The body 12 may be readily and economically molded of a material such as a thermoplastic resin. The body may take a wide variety of shapes and forms, taking into consideration the various requirements of manufacturing techniques to be employed, the number and size of the female contacts to be used, the decorative exterior design desired, providing any desired type of ribbing or means for assisting in grasping the connector during the joining and disconnecting of the connector to a complementary plug. In this instance, the body takes the form illustrated in FIGURE 1, and is of generally pentagonal cross-section with the flat outer end face lo from which the sides of the connector extend in generally perpendicular relation and subsquently converge to form an opposite end from which the cord 14 extends. Various of the sides may be formed with transverse series of ridges and grooves, as Sil, to assist in grasping the connector.
Wires extend from the cord 14 and are suitably electrically connected with the female contacts 4G, 42 and 44, respectively. This assembly, along with the barrier 2S, may be held operatively associated as illustrated, in any suitable manner as by a jig. The yieldable body 12 is then molded thereabout to hold the barrier and the contact and cord assembly operatively enclosed within the body.
in the illustrated embodiment the barrier 23 is a plate having .a fiat inner face 52 and parallel thereto a flat outer face 53. The mold is such as to provide the openings 20, 22 and 24 extending inwardly from the end face 16 of the body and in alignment with the respective barrier opening and the female contacts. The contacts 44) and 42 are located in opposed relationship to each other as shown, while the third or ground contact 44 is located in spaced relation from adjacent sides of each of the contacts 4) and 42, and in general alignment with an imaginary line run ning parallel to and centrally of the contacts 4%'9 and 42. The contacts 40, 42 and 44 are positioned generally perpendicular to the inner face 52 of the barrier 28 and the mold is such as to form the body and face 16 generally perpendicular to the outer face S3 of the barrier 23. Since the body 12 is molded around the barrier 2S, the outer edge and the upper `and lower faces of the barrier are effectively sealed against moisture.
The two female contacts 40 and 42 are of similar construction and are each intended to receive one of a pair of male contacts which are of generally rectangular crosssection, as previously mentioned. Briefly, each of the female contacts 4t) and 42 includes a jaw section 54 (FIGURE 2) at an outer end of the contact, the jaw sections being adapted to receive and make contact with the associated male contacts. The female contacts 4t) and 42 further each include a section 55 at its opposite inner end. Each section 55 has a pair of ears 56 which are crimped to the respective lead wires from the cord 14, and an intermediate retroverted ear 57 for maintaining the base region of the opposing jaws in closely adjacent relation.
In order for the female contacts 46, 42 and 44 of the connectors llt) to receive the associated male contacts of the complementary plug, the series of access openings 20, 22 and 24, respectively, are provided as previously noted, and are in generally alignment with the associated female contacts and are substantially perpendicular to the end face 16 and the plane of the barrier 2S. Each of the access openings is formed with a cross-section slightly larger than the cross-section of the associated contact of the complementary polarized plug for easy insertion of the plug contacts into the connector contacts. In this case, the openings 20 and 22, which lead to the respective female contacts 40 and 42, are of generally rectangular cross-section and are suitably beveled at their outer extremities to provide for greater ease in locating and joining the male plug to the female connector.
With particular reference to FGURES 3, 5 and 6, the ground female contact 44 is intended to receive a ground male contact having a crosssection which is D-shaped or non-circular or which is substantially circular. As shown, the female ground contact 44 includes a D-shaped tubular portion 6d for receiving the associated male contact, and a portion 62 crimped to a ground lead wire from the cord 14. The ground contact is made from sheet metal and is formed with a longitudinal seam 66 where both edges of the metal meet. A tab 68 is struck out of the sheet metal to form a bottom for the contact. The cross-section of the opening 24 conforms generally to the opening crosssection of the tubular receiving section di) of the female ground contact 44 and its outer end may be beveled for easy access of the male ground contact.
As the connector body 12 is generally made of a moldable and relative soft and resilient dielectric material, such as rubber or thermoplastic resin, the openings 20, 22 and 24 occasionally may be subject to deformation or displacement as an incident to the forceable insertion of the illfitting or improper contacts of a male plug. To overcome this, the barrier 28 is made in a single piece and the openings and passages are so located and are of such sizes and shape that they will fit and accommodate the male contact members of the appropriate male connector plug and no other. The barrier 2S may be stamped or otherwise fifabricated from any relatively rigid dielectric material such as a paper base phenolic sheet.
The outer ends of the female contacts 4i? and 42 are positioned inwardly of the inner barrier face 42 so that the jaws 54 may flex in normal manner upon insertion or withdrawal of the associated male contacts. The female ground contact 44 extends through the barrier passage 34 and the edge of the barrier defining this passage closely encircles the mouth portion of the tubular part 6i), permitting only slight spreading of the contact. However, permanent deformation or distortion of the mouth is effectively prevented. Also the barrier 28 being rigid and made in one piece prevents any of the female contacts from shifting relative to any of the other female contacts.
The barrier 28 is provided with two additional holes, a relatively large hole 70 in the center of the barrier and a smaller hole 72 adjacent the smaller passage 32. The smaller olf-center hole 72 is provided to indicate to the molding operator the correct orientation of the barrier when assembling it on the molding fixture. The larger hole 7@ provides a passage through which plastic can flow during the molding operation, thus resulting in improved means for anchoring all of the components together.
Various changes and modifications may be made in the disclosed construction without departing from the principles of the present invention.
Various features of the invention are set forth in the accompanying claims.
What is claimed is:
1. A polarized female electric connector comprising a molded relatively yieldable dielectric body having an end face, at least three elongated female contact members having outer ends adjacent said end face and extending therefrom generally parallel to each other within said body, each of said female contact members being adapted to receive an associated male contact extending from a complementary male plug having male contacts of different cross section, one of said female contact members being a grounding connection generally non-circular and made of sheet metal formed into a tube with a longitudinal seam, said body having an opening therein extending from said end face toward each of said female contact members for providing access to each female contact member by the associated male contact, and a relatively rigid one-piece sheet dielectric barrier within said body, extending across said openings inwardly of said end face and encased in said body, said barrier having a plurality of passages therethrough for accommodating the male contacts of the complementary male plug, one of said passages receiving the mouth of said tubular female contact member and closely encircling said mouth for effectively preventing distortion of said tubular female Contact member at said mouth, the other passages being in alignment with the other openings and being of slightly larger cross section than the complementary associated male contacts, the outer ends of said other female contact members being spaced inwardly from the inner face of the barrier.
2. A polarized female electric connector comprising a molded relatively yieldable dielectric body having an end face, at least three elongated female contact members having outer ends adjacent said end face and extending therefrom generally parallel to each other within said body, each of said female contact members being adapted to receive an associated male contact extending from a complementary male plug, the male contacts being of different cross section, one of said female contact members being a tubular ground connection formed of sheet metal with a longitudinal seam, said body having openings therein extending from said end face toward said respective female contact members for providing access to said female contact members by the associated male contact members, and a relatively rigid one-piece sheet dielectric barrier enclosed within said body and extending across said openings inwardly of said end face, said barrier having a plurality of passages therethrough, one of said passages receiving the mouth of said tubular female vcontact member and closely encircling said mouth for effectively preventing distortion of said one female contact member at said mouth, the other passages being in alignment with the other openings and being of slightly larger cross section than their associated male contacts, the outer ends of the female contact members aligned with said other passages being spaced inwardly from the insert, said barrier having a perforation which is lled with said body material whereby portions of said body on op' posite sides of said barrier are integrally united together.
References Cited by the Examiner UNITED STATES PATENTS 10 .OSEPH D. SEERS, Primary Examiner.