Method for manufacturing a contact element, in particular a contact pin, as well as a contact element manufactured according to this method and a device for manufacturing such a contact element.

Abstract

The invention relates to a method for manufacturing a contact element (1) comprising a base body (2) with an insertion zone (10), wherein the insertion zone (10) has at least one profile (11a, 11b) with at least one outwardly projecting projection (12) in at least one area thereof, wherein the contact element (1) is cut out from a strip of material in a first process step as a contact element blank (1'). According to the invention, the contact element blank (1') is manufactured with an outer contour (5a) smaller than the final dimension of the contact element (1) and is placed in an embossing die (33) whose embossing contour (33a) corresponds to the outer contour of the contact element (1), and the contact element blank (1') is then subjected to an embossing process by which the outer contour (5a) of the contact element blank (1') is transformed into the outer contour of the contact element (1).

Description

[0001] The invention relates to a method for manufacturing a contact element, in particular a contact pin, wherein the contact element has a base body with an insertion zone, wherein the insertion zone has at least in one area at least one profile with at least one outwardly projecting projection, wherein the contact element is cut out of a strip of material as a contact element blank in a first process step, as well as a contact element manufactured according to this method and a device for manufacturing it.

[0002] Electrical contact elements, in particular contact pins, are known. To establish an electrical connection, the contact element is inserted with its insertion zone into a socket or a hole-like recess, such as a hole in a printed circuit board. In order to form a sufficiently stable mechanical and electrical connection between the contact element and its associated component, the insertion zone is provided that, at least in one area, it has a profile with at least one outwardly projecting projection.

[0003] The increasing miniaturization of such electrical contact elements, in particular, leads to higher demands on their dimensional accuracy and manufacturing quality. A low residual contamination level is essential to ensure a sufficiently good electrical and / or mechanical connection, even with a small contact area between the insertion zone of the contact element and the component receiving it. These stringent manufacturing requirements apply even more so to the profile of the insertion zone. Such insertion zones are often designed with a sawtooth or fir-tree profile, meaning they feature outward-projecting protrusions from the base body. The edges of these protrusions should be as sharp as possible.

[0004] Up to now, such electrical contact elements have been cut from a carrier strip in a stamping press, ensuring precise dimensions, i.e., their final dimensions. This allows for precise manufacturing with a high production rate. However, there is a risk of protrusions, etc., occurring in exposed areas of the press-fit zone – for example, in the corners of the profile of this zone. To counteract this, it is often stipulated that the cutting process of a contact element is carried out by two successive cuts. Such a procedure is detrimental to a high production rate and adversely increases manufacturing costs.

[0005] From DE 44 00 499 A1, a contact spring with a contact head is known, the contact head having a convex contact surface with two side faces. To smooth out cutting marks in the contact surface resulting from a previous stamping process, at least one recess is embossed into the side faces of the contact head. This creates a material flow, and this material flow during embossing smooths and widens the contact surfaces of the contact head.

[0006] From DE 10 2012 206 035 A1, an electrical contact with a sealing rib is known. The contact has a housing in which an electrical conductor is embedded. The housing has a recess, the electrical conductor being inserted into the recess, and the space between the conductor and the housing being filled with a sealing material. The conductor extends longitudinally through the housing and has a rib that extends transversely to the longitudinal direction of the conductor and projects a predetermined height beyond one side of the conductor, with the sealing material being arranged on one side of the rib. The respective ribs are preferably inserted into the conductor by means of a pressing process.

[0007] US Patent 5,163,223 A discloses a method for manufacturing an electrical contact pin with perfectly rounded contact surfaces. In this process, a strip of metal is embossed using a first die, creating an opening in one surface and a projection that extends from the second surface. The processed metal strip is then inserted between a second die and a second die, the second die having an opening that is smaller than the opening produced by the first die.

[0008] It is therefore an object of the present invention to further develop a method for manufacturing a contact element of the type mentioned above in such a way that dimensionally accurate production is possible in a simple manner. Furthermore, the invention relates to a contact element manufactured according to the method of the invention and to a device for its manufacture.

[0009] This problem is solved by the method according to the invention in that the contact element blank is manufactured with an outer contour smaller than the final dimension of the contact element and is inserted into an embossing die whose embossing contour corresponds to the outer contour of the contact element, wherein there is a gap between the outer contour of the contact element blank and the embossing contour, and that the contact element blank is then subjected to an embossing process in which the material of the base body flows into the gap between the outer contour of the contact element blank and the embossing contour of the embossing die, so that the outer contour of the contact element blank is transferred into the outer contour of the contact element.

[0010] The contact element according to the invention is characterized in that the contact element is stamped from a contact element blank having an undersized dimension.

[0011] The device according to the invention provides that the embossing die has an embossing contour which corresponds to the outer contour of the contact element to be produced, and wherein the embossing punch acts on the contact element blank inserted into the embossing die to form this contact element blank into the contact element, such that during this forming process the material of the base body flows in an intermediate space between the outer contour of the contact element blank inserted into the embossing die and the embossing contour of the embossing die, so that the outer contour of the contact element blank is transferred into the outer contour of the contact element.

[0012] The measures according to the invention advantageously provide a method for manufacturing a contact element, such a contact element, and a device for its manufacture, which are characterized in that dimensionally accurate manufacturing of the contact element, in particular a contact element with a number of outwardly directed projections of one or more profiles of the insertion zone, becomes possible in a simple manner. The contact element manufactured by the method according to the invention is characterized by its high dimensional accuracy. The method and the device according to the invention also advantageously allow the production of particularly sharp corners of the projection(s) of at least one toothing of the insertion zone.

[0013] Advantageous further developments of the invention are the subject of the dependent claims.

[0014] Further details and advantages of the invention can be found in the exemplary embodiments described below with reference to the figures. These show: Fig. Figures 1a to 1c show a schematic representation of a first embodiment of a method for manufacturing an electrical contact element. Fig. 2a to 2c a schematic representation of a second embodiment of a method for manufacturing an electrical contact element, and Fig. Figures 3a to 3c show a schematic representation of a third embodiment of a method for manufacturing an electrical contact element.

[0015] The Fig. 1a and Fig. Figure 1b schematically shows a process for producing a product generally designated by 1 and in Fig. Figure 1c shows an enlarged view of the contact element based on the device 30 used in the described method. Such a contact element 1 has a base body 2, which in the case described here is cuboid in shape and has an upper surface 2a, a lower surface 2b, and two side surfaces 2c and 2d. Profiles 11a and 11b of an insertion zone of the contact element 1, generally designated 10, are formed on the latter two side surfaces 2c and 2d. Each of these profiles has a number of projections 12 extending outwards from the base body 2. A connection area 13 adjoining the insertion zone 10 serves to be connected to corresponding electrical leads (not shown). Such an electrical contact element 1 is generally known and therefore does not need to be described in detail.It is obvious to those skilled in the art that the embodiment of the electrical contact element 1 described here is merely exemplary. This applies in particular to the design of the base body 2 and / or the design of the projections 12 of the profiles 11a and 11b.

[0016] While known methods for manufacturing such an electrical contact element 1 provide that this contact element 1 is manufactured to its final dimension, the method described here advantageously provides that the contact element 1 to be manufactured is undersized, at least in the area of ​​its insertion zone 10, and then brought to its final dimension by an embossing process. This procedure is illustrated by the following: Fig. 1a and Fig. 1b only schematically shown device 30 explained. Fig. Figure 1a shows an embossing die 31 with a convex embossing surface 31' of the device 30 and an embossing insert 32 arranged opposite the embossing die 31, with a convex embossing surface 32', and an embossing die 33. The embossing die 31 is driven by a drive device not shown in the figures. Such a device 30 is known and therefore does not need to be described in more detail. Fig. 1b shows a section through the Fig. 1a along line AA.

[0017] As already explained above, the described method does not immediately produce a contact element 1 manufactured to final dimensions, but rather a contact element blank 1' which, compared to the finished contact element 1, has a smaller dimension at least in the area of ​​the insertion zone 10. Fig. Figure 1b shows the contact element blank 1' inserted into the embossing die 33. Its outer contour is represented by line 5a. An embossing contour 33a of the embossing die 33 corresponds to the outer contour of the contact element 1 to be produced from the contact element blank 1'.

[0018] In the described process, the contact element blank 1' is subjected to force by the embossing die 31, causing the material of the base body 2 of the contact element 1 to flow in the direction of arrows P, thus creating an embossing effect: The material of the base body 2 flows into the space 34 between the outer contour 5a of the contact element blank 1' and the embossing contour 33a of the embossing die 33. The contact element blank 1' is thus transformed into the contact element 1. The latter is characterized by its precise final dimensions and, in particular, by its constant dimensional accuracy. Furthermore, the procedure described above makes it possible, if necessary, to form sharp corners on the projections 12.

[0019] In the Fig. Figures 2a to 2c show a second embodiment, in which corresponding components are designated with the same reference numerals and their design and function are not described in further detail. The essential difference between the two embodiments is that in the first embodiment, the embossing die 31 and the embossing insert 32 are each designed with a convex embossing surface 31' and 32' respectively, while in the second embodiment, the embossing surface 31' of the embossing die 31 and the embossing surface 32' of the embossing insert 32 are concave.

[0020] In the Fig. Figures 3a to 3c depict a third embodiment, in which corresponding components are again designated with the same reference numerals and are not described in further detail. The essential difference between the first two embodiments and the third embodiment is as follows: In the first two embodiments, a contact element blank 1' is cut to undersize, inserted into the embossing die 33, and then embossed as described. In the third embodiment, a double embossing process is now provided for. As shown in the illustration of the Fig. As can be seen from Figure 3a, a first embossing process is carried out with an embossing die 31a having parting projections 35a and 35b, so that a material protrusion 36a, 36b, essentially a "material bead", is formed in the area of ​​the base body 2 adjoining the parting projections 35a, 35b. Then, the contact element blank 1' with undersize is cut out from the pre-embossed material strip as described above. This contact element blank 1' is then placed back into the embossing die 33 and an embossing process corresponding to the embossing processes of the two first embodiments is carried out. This is shown in Fig. Figure 3b shows an embossing die 31 with a flat embossing surface 31'. This die presses against the material protrusions 36a, 36b, which in turn results in the material of the base body 2 flowing.

[0021] In the case described here, the embossing die 31 has a flat embossing surface 31'. However, it is also possible to use a concave embossing surface 31', as in the first embodiment, or a concave embossing surface 31', as in the second embodiment. Of course, other contours of the embossing die 31 are also possible.

[0022] In summary, the described measures create a method for the simple, dimensionally accurate production of a contact element 1, in particular a contact element 1 with a number of outwardly directed projections 12 of one or more profiles 11a, 11b. The described contact element 1 is characterized by its high dimensional accuracy and, in particular, by its sharp corners. This is advantageous when inserting the described contact element 1 into a corresponding receptacle, e.g., a connector socket or a hole in a printed circuit board. The described device has the advantage that predominantly standard components can be used.

Claims

[1] Method for manufacturing a contact element (1) comprising a base body (2) with an insertion zone (10), wherein the insertion zone (10) has at least one profile (11a, 11b) with at least one outwardly projecting projection (12) in at least one area thereof, wherein the contact element (1) is cut out from a strip of material as a contact element blank (1') in a first process step, characterized by, that the contact element blank (1') is manufactured with an outer contour (5a) smaller than the final dimension of the contact element (1) and is inserted into an embossing die (33) whose embossing contour (33a) corresponds to the outer contour of the contact element (1), wherein a space (34) is present between the outer contour (5a) of the contact element blank (1') and the embossing contour (33a), and that the contact element blank (1') is then subjected to an embossing process in which the material of the base body (2) flows into the space (34) between the outer contour (5a) of the contact element blank (1') and the embossing contour (33a) of the embossing die (33), so that the outer contour (5a) of the contact element blank (1') is transformed into the outer contour of the contact element (1). [2] Method according to claim 1, characterized by , that the embossing process of the contact element blank (1') is carried out by means of an embossing die (31, 31a). [3] Method according to claim 2, characterized by , that an embossing die (31, 31a) with a concave, convex or planar embossing surface (31') is used. [4] Method according to any of the preceding claims, characterized by , that a pre-embossing process is carried out before the contact element blank (1') is cut out of the carrier strip to form at least one material protrusion (36a, 36b) in the base body (2). [5] Method according to claim 2, characterized by , that a further die (31a) is used which has at least one separating projection (35a, 35b). [6] Method according to any of the preceding claims, characterized by , that at least one or the material protrusions (36a, 36b) are subjected to force by the embossing die (31). [7] Contact element (1), comprising a base body (2) having an outer contour with at least one projection (12), characterized by, that the contact element (1) is stamped from a contact element blank (1') that is undersized. [8] Device for manufacturing a contact element (1) which has a base body (2) with an insertion zone (10), wherein the insertion zone (10) has at least one area of ​​the same at least one profile (11a, 11b) with at least one outwardly projecting projection (12), wherein the device has an embossing die (31), an embossing insert (32) and an embossing matrix (33), characterized by, that the embossing die (33) has an embossing contour (33a) which corresponds to the outer contour (5a) of the contact element (1) to be produced, and wherein the embossing punch (31) acts on the contact element blank (1') inserted into the embossing die (33) to transform this contact element blank (1') into the contact element (1), such that during this forming process the material of the base body (2) flows in an intermediate space (34) between the outer contour (5a) of the contact element blank (1') inserted into the embossing die (33) and the embossing contour (33a) of the embossing die, so that the outer contour (5a) of the contact element blank (1') is transferred into the outer contour of the contact element (1). [9] Device according to claim 8, characterized by , that the embossing die (31, 31a) has a concave, convex or flat embossing surface (31'). [10] Device according to any one of the preceding claims, characterized by, that at least one further die (31a) having at least one separating projection (35a, 35b) is provided.

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