Contact insertable in a metallized hole of a printed circuit card and process

Claim 1

The combination of a printed circuit card (6) of a predetermined thickness having a hole (5) formed therein, said hole having a metallized contact surface layer (7) on its walls, with an elongated contact terminal pin element insertable in the hole, for making electrical connection with the metallized contact surface layer (7) of the hole and for mechanical attachment to the printed circuit card (6), wherein the terminal pin element comprises: a first end portion (1) of polygonal cross-section and suitable for a wire-wrap connection dimensioned to pass through the hole (5) and project beyond one of the faces of the card (6) when the contact pin element is in an inserted position in the card; a second end portion (2) of polygonal cross-section and suitable for a wire-wrap connection dimensioned to project beyond the other face of the card when the contact is in the inserted position; an intermediate portion (3) of twisted polygonal cross-section and of a length corresponding about to the thickness of said card connecting the first and second end portions, the surfaces of said intermediate portion having edges defining twisted corners; said end portions and intermediate portion being substantially aligned on a common axis which is also the axis of twist of said intermediate portion, whereby said terminal element is inserted by only axial pressure on said second end portion while permitting free rotation of the pin element to self-twist the pin element into the hole, and wherein said intermediate portion, when inserted in said hole, engages by said twisted corners the metallized interior surface layer (7) of the hole and at the same time ensures mechanical retention of the terminal pin element in the hole, by deformation of said metallized contact surface layer in a spiral path which leaves said surface layer electrically continuous and forms a gastight connection preventing corrosion of the contact surface of said metallized layer which is in engagement with said pin element.

Claim 11

A method of inserting a contact terminal pin element into a hole (5) of a printed circuit card (6), wherein the hole (5) has a metallized surface (7), and said contact terminal pin element comprises an elongated metal contact terminal pin having a first end portion of polygonal cross-section and suitable for a wire-wrap connection (1) dimensioned to freely pass through the hole (5) and project beyond one the faces of the card (6) when the contact is in an inserted position, a second end portion of polygonal cross-section and suitable for a wire-wrap connection (2) dimensioned to project beyond the other face of the card when the contact is in the inserted position an intermediate portion (3) of twisted polygonal cross-section and of a length corresponding about to the thickness of the card, connecting the first and second end portions, in which the surfaces of the intermediate portion have edges defining corners twisted about a longitudinal axis of the pin element for a limited angular extent to form a spiral structure running between said first and second end portions, said method comprising the steps of aligning the first end portion with the hole, and axially inserting the first end portion through the hole and exerting only axial pressure on the second end portion while permitting free rotation of the contact terminal pin element to self-twist the element into the hole by said limited angular extent to seat the twisted intermediate portion defining the spiral structure within the hole (5), the corners and adjacent portions of the spiral structure, during insertion engaging the metallized interior surface of the hole under the axial insertion pressure while permitting free rotation of the contact terminal pin element, ensuring mechanical retention of the terminal pin element in the hole and electrical connection, by deforming said metallized interior surface in a spiral path while leaving it electrically continuous and forming a gastight corrosion-resistant connection, and transferring said axial pressure from said intermediate portion of contact pin element to said card when said intermediate portion has fully entered into said hole, to stop further advance of said pin before said axial pressure is discontinued.

Claim 12

A method of inserting a contact terminal pin element into a hole (5) of a printed circuit card (6), wherein the hole (5) has a metallized surface (7), and said contact terminal pin element comprises an elongated metal contact terminal pin having a first end portion of polygonal cross-section and suitable for a wire-wrap connection (1) dimensioned to freely pass through the hole (5) and project beyond one the faces of the card (6) when the contact is in an inserted position, a second end portion of polygonal cross-section and suitable for a wire-wrap connection (2) dimensioned to project beyond the other face of the card when the contact is in the inserted position an intermediate portion (3) of twisted polygonal cross-section and of a length corresponding about to the thickness of the card, connecting the first and second end portions, in which the surfaces of the intermediate portion have edges defining corners twisted about a longitudinal axis of the pin element for a limited angular extent to form a spiral structure running between said first and second end portions, said method comprising the steps of aligning the first end portion with the hole, and axially inserting the first end portion through the hole and exerting only axial pressure on the second end portion while permitting free rotation of the contact terminal pin element to self-twist the element into the hole by said limited angular extent to seat the twisted intermediate portion defining the spiral structure within the hole (5), the corners and adjacent portions of the spiral structure, during insertion engaging the metallized interior surface of the hole under the axial insertion pressure while permitting free rotation of the contact terminal pin element, ensuring mechanical retention of the terminal pin element in the hole and electrical connection, by deforming said metallized interior surface in a spiral path while leaving it electrically continuous and forming a gastight corrosion-resistant connection, and transferring said axial pressure from said intermediate portion of contact pin element to said card when said intermediate portion has fully entered into said hole, to stop further advance of said pin before said axial pressure is discontinued.