Connector for electrical connections

Abstract: A connector for electrical connections comprising a laminar body (11) made of conducting material with at least one pair of first mutually opposite and substantially rigid wings (12) which form a recess (13) inside which two elastic flaps (14) converge towards the bottom, each one of the elastic flaps (14) being connected with an L-shaped configuration (15) to a corresponding one of the first wings (12). An electrical conductor with an insulating sheath can be inserted between the elastic flaps (14), a part (14a) of the edges whereof is sharp, up to their free ends (16). Each one of the first wings (12) has, at its edge directed towards the corresponding flap, a first raised portion (18) adapted to form a stroke limiter for the opening of the flap.

Description: The present invention relates to a connector for electrical connections. Conventional electrical connections and wirings now commonly use particular connectors obtained starting from a lamina, the electrical contact elements whereof are capable of adequately cutting into the insulating sheath of the conductor, if present, and of penetrating it to provide the contact. Connectors are currently commercially available which comprise a laminar body made of conducting metallic material with at least one pair of substantially rigid opposite wings forming a recess between them; two elastic electrical contact flaps converge inside said recess towards the bottom and blend with one of the wings with an L-shaped configuration. A conductor can be inserted and locked between the elastic flaps, providing an electrical contact. The opposite edges of the flaps are provided at least with sharp parts, so that during the insertion of the conductor between said flaps the insulating sheath of the conductor is cut into and said flaps can penetrate it, providing contact with the conducting part. The lamina from which the connector is obtained is blanked by means of punches which must have a certain thickness in order to achieve an effective cutting action. Therefore, the two flaps are first blanked at some distance from each other and are then moved mutually closer until their free ends, which must accommodate the conductor, are in contact, said ends being also provided with a certain elastic preloading. The two flaps are currently moved mutually closer by providing a slot for each flap in the region for blending with the outer wings and by then forming a stud which is superimposed on the slot. However, the slots have the important drawback that they weaken the structure in the very region where the stresses induced after installation by the presence of the conductor are discharged. In order to eliminate the above drawbacks, an innovative connector for electrical connections is the disclosed in Italian industrial invention patent application no. PD 93 A 000187 of September 24, 1993 in the name of the same Applicant. Said connector also comprises a laminar body made of conducting material with at least one pair of mutually opposite and substantially rigid wings, which form a recess inside which two elastic flaps converge towards the bottom, each flap blending with a corresponding wing with an L-shaped configuration. The flaps are preloaded so as to push against each other by a deformation of the wings which is meant to move their ends mutually closer. An electrical connector with an insulating sheath can be inserted between the elastic flaps, a part of the edges whereof is sharp, up to the free ends. Said connector ensures, with respect to the previous conventional types, higher reliability of the connection in addition to the absence of the danger of shearing the conductor, particularly if the component on which the connector is fitted is subjected to vibration. However, despite providing substantial improvements over conventional connectors, this connector is still affected by a drawback which is highlighted in practical application and is due to a still imperfect contact provided between the ends of the flaps between which the electrical conductor is inserted. Moreover, both conventional connectors and said above-mentioned connector have the significant drawback related to the fact that the insertion of wires the cross-section whereof is close to the accommodation size limits of the flaps forces the free end of said flaps to perform significant strokes, with the danger of deforming them with respect to the plane of the body that constitutes the connector. Moreover, the cutting of any sheath provided on the wire that can be inserted between the flaps is sometimes not optimum. A principal aim of the present invention is to solve the above-described drawbacks of conventional connectors. Accordingly, an object of the present invention is to provide a connector in which the free ends of the flaps can accommodate conductors with a cross-section that is close to the acceptable size limits without deforming with respect to the plane of the body of said connector. Another object of the present invention is to provide a connector in which effective contact between the free ends of the flaps is ensured. Another object of the present invention is to provide a connector in which the sheath that possibly covers the electric wire is cut into effectively in order to allow optimum electrical contact of the flaps. Another object of the present invention is to provide a connector which can be manufactured without particular difficulties with conventional equipment and facilities. Another object of the present invention is to provide a connector that is adapted for electrical conductors over a wide range of diameters and types. This aim, these objects, and others which will become apparent hereinafter are achieved by a connector for electrical connections, as defined in claim 1. Further characteristics and advantages of the present invention will become apparent from the following detailed description of two embodiments thereof, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a perspective view of a connector for electrical connections, according to the invention, in a first embodiment; figure 2 is a detail view of the connector of figure 1; figure 3 is a perspective view of another detail of the connector of figure 1; figure 4 is a perspective view of part of a connector for electrical connections, according to the invention, in a second embodiment; figures 5 to 7 are views of other embodiments of the connector which differ from the preceding ones in the part lying opposite to the first wings. With particular reference to figures 1 to 3, a connector for electrical connections, according to the invention, is generally designated by the reference numeral 10 in a first embodiment. The connector 10 comprises a laminar body 11 made of conducting material, such as copper or copper alloy, with two first mutually opposite and substantially rigid wings 12 which form a recess 13 inside which two elastic flaps 14 converge towards the bottom, each one of said flaps being blended by means of an L-shaped portion 15. The flaps 14 touch each other at a flat region of their edge related to the corresponding free ends, which are designated by the reference numeral 16. The flaps 14 also form, as a whole, a space 17 which tapers starting from the region of the L-shaped portions 15 up to the mutual contact region. Each one of the first wings 12 has, at its edge directed towards the corresponding flap 14, a first raised portion 18 which is adapted to form a stroke limit for the opening of said flap. More specifically, each one of the first raised portions 18 protrudes in a region of the edge of the corresponding first wing 12 which substantially faces the free end 16 of the corresponding flap 14. Moreover, in this case each one of the first raised portions 18 has a substantially semicircular contour. A second raised portion 19 protrudes from each one of the flaps 14, at the sharp edge 14a which is directed towards the other flap 14, and has a cutting profile that is adapted to cut into the sheath of an insulated electrical conductor, not shown. The second raised portions 19 cut into the sheath of the conductor, making the flaps 14 penetrate the insulating layer to broadly rest, by means of the further cutting action of the edges 14a, against the core with their free ends, thus providing safe and effective electrical contact. The flaps 14 are formed by blanking the lamina from which the entire connector 10 is formed, by means of a punch which forms them with said flat regions at the free ends 16; however, said flat regions are at a certain distance from each other and from the bottom of the recess 13 directly after punching. This is due to the need to provide punches having a certain thickness. In the finished configuration, the two flaps 14, in addition to having their corresponding free edges 16 in mutual contact, must be appropriately preloaded. According to the invention, each one of the flaps 14 has an inclined coined region 20 of at least one of the surfaces delimited by the edges. Said coined region 20 in practice runs from a region of the corresponding flap 14 which is adjacent to the L-shaped portion 15 towards the free end 16 thereof, gradually reducing its thickness. Said coined region 20 is adapted to make the contact between the free ends 16 of the flaps 14 effective and safe. Moreover, in order to move the bottom of the recess 13 closer to the free ends 16 of the flaps 14 without preventing their elastic movements, at the same time preventing a conductor from disengaging from contact by entering the recess 13, a stud 21 is formed in the bottom of said recess 13 and affects the edge of said recess so as to move a portion thereof towards the flaps 14. Two second wings 22 are arranged in the body 11 in opposition to the first wings 12 and form a cavity 23 with a radiused bottom 24 which is adapted to accommodate an electrical wire and/or a terminal board, not shown. In this first embodiment, the free end of each one of the second wings 22 is inclined so as to form, together with the other free end, a space 25 which tapers towards the body 11. The edge 26 of each one of the free ends of the second wings 22 that is directed inwards also has a cutting profile which is adapted to cut into the sheath of any conductor inserted in the cavity 23. As regards the production process, it entails in succession the following operations: the blanking of a metal lamina from a continuously fed strip so as to form the edges of the space 17 for the insertion of the conductor; the chamfering of the edges that delimit the space 17 so as to form the corresponding cutting edges 14a and the second raised portions 19; the blanking of said lamina so as to form the edge of the recess 13 and complete the flaps 14; the punching of said lamina so as to form the stud 21 for moving the bottom of the recess 13 towards the flaps 14 and coin said flaps; the moving of said free ends 16 towards each other; the blanking of said lamina so as to complete said body 11 with said wings 12 in a spaced configuration; and the gauging of said body 11, moving the spaced ends of said wings 12 towards each other. With particular reference to figure 4, a connector, according to the invention, is generally designated by the reference numeral 100 in a second embodiment. Like the connector 10, the connector 100 comprises a body 101 with two first wings which form a recess inside which two elastic flaps converge towards the bottom; each flap is blended, by means of an L-shaped portion, to a corresponding first wing; reference is made, for their detailed description, to what has been described regarding the first embodiment, since here there are no substantial differences. The connector 100 instead differs from the connector 10 in that it comprises two second wings 102 which have a particular shape in order to accommodate electrical tabs which are not shown. At the free ends of each one of the second wings 102 there protrudes a corresponding third raised portion 103, adapted to ensure electrical contact with the tabs as well as locking in association with the other corresponding third raised portion 103 of an electronic terminal board. With particular reference now to figure 5, in an alternative embodiment adapted for electronic cards, the part of the connector that lies opposite to the first wings assumes the shape of a rod-like male element 202 which can be inserted in a corresponding hole, not shown, of an electronic board. In a further alternative embodiment, there are provided tabs of various sizes; figures 6 and 7 illustrate two types, designated by the reference numerals 302 and 402 respectively, for connection to corresponding female Faston connectors. In practice, it has been observed that the present invention has achieved the intended aim and objects. In particular it should be noted that the connector according to the invention solves both the problems related to the deformations of the free ends of the flaps and the problems related to an effective cutting of the sheath of the conductor and of the enamel of the wires. It should also be noted that the connector according to the invention can connect the wire inserted between the flaps both to another cable and to electrical tabs, to female Faston connectors, and to electronic cards. It should also be noted that the present invention is structurally simple and can be produced by means of conventional methods. The present invention is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept. All the details may furthermore be replaced with other technically equivalent elements. The materials and the dimensions may be any according to the requirements. Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims: A connector for electrical connections of the type that comprises a laminar body (11) made of conducting material with at least one pair of first mutually opposite and substantially rigid wings (12) which form a recess (13) inside which two elastic flaps (14) converge towards the bottom, each one of said elastic flaps (14) being connected with an L-shaped configuration (15) to a corresponding one of said first wings (12), an electrical conductor with an insulating sheath being insertable between said elastic flaps (14), a part (14a) of the edges whereof is sharp, up to their free ends (16), each one of said first wings (12) having, at its edge directed towards the corresponding flap (14), a first raised portion (18) which is adapted to form a stroke limiter for the opening of said flap (14), characterized in that each one of said first raised portions (18) protrudes in a region of the edge that substantially faces the free end (16) of said corresponding flap (14). The connector according to claim 1, characterized in that each one of said flaps (14) has an inclined coined region (20) of at least one of the surfaces formed by the edges. The connector according to claim 2, characterized in that said coined region (20) affects both of said flaps (14) on a single side. The connector according to claim 2, characterized in that said coined region (20) runs from a region that is adjacent to said connecting L-shaped portion (15) up to the free end (16) of each one of said flaps (14), gradually reducing their thickness. The connector according to one or more of the preceding claims, characterized in that a second raised portion (19), with a sharp profile adapted to cut into the sheath of the inserted electrical conductor, protrudes from each one of said flaps (14) at its edge that is directed towards the other flap. The connector according to claim 5, characterized in that each one of said second raised portions (19) protrudes proximate to the corresponding connecting L-shaped portion (15). The connector according to one or more of the preceding claims 5 or 6, characterized in that each one of said second raised portions (19) has a substantially semicircular shape. The connector according to one or more of the preceding claims, characterized in that two second wings (22,102) protrude from said body (11) in opposition to said first wings (12) and form a cavity (23) with a radiused bottom (24) that is adapted to accommodate an electric wire and/or a terminal board. The connector according to claim 8, characterized in that a third raised portion (103) protrudes from each one of said second wings (102) and faces the other second wing, said two third raised portions (103) cooperating, up on assembly, to the accommodation and locking of a terminal board. The connector according to claim 9, characterized in that each one of said third raised portions (103) protrudes at the free end of a corresponding second wing (102). The connector according to claim 9, characterized in that each one of said third raised portions (103) has a rounded profile. The connector according to claim 8, characterized in that the free end of each one of said second wings (22) is shaped so as to form a cutting edge (26). The connector according to one or more of claims 1 to 8, characterized in that the part that lies opposite to said first wings (12) is shaped like a rod-like male element (202). The connector according to one or more of claims 1 to 7, characterized in that the part that lies opposite to said first wings (12) is shaped like a tab (302,402). A method for producing a connector comprising a laminar body (11) made of conducting material with at least one pair of first mutually opposite and substantially rigid wings (12) which form a recess (13) inside which two elastic flaps (14) converge towards the bottom, each one of said first wings (12) having, at its edge directed towards the corresponding flap (14), a first raised portion (18) which is adapted to form a stroke limiter for the opening of said flap (14), each one of said first raised portions (18) protruding in a region'of the edge that substantially faces the free end (16) of said corresponding flap (14), characterized in that it comprises the steps of: blanking a metallic lamina in strip form which is fed continuously so as to form the edges of said flaps that delimit the conductor insertion space; chamfering said edges of said flaps so as to form corresponding cutting edges and a second raised portion; blanking said lamina so as to form the edge of said recess and complete said flaps; punching said lamina so as to form a stud for moving the bottom of the recess towards said flaps and providing a coined region thereon; moving free ends of said wings mutually closer; blanking said lamina so as to complete said body with said wings in spaced configuration; gauging said body, moving the spaced ends of said wings towards each other.

Inventors: PIOVESAN GIANNI, PIOVESAN, GIANNI
Applicants: INARCA SPA, INARCA S.P.A.
Application year: 1997
Main classification: H01R4
IPC codes: H01R4