Plug-connector with embedded pre-manufactured plug contact supporting means and method for manufacturing a plug-connector

The invention is directed to a plug-connector for an automotive device and to a method for manufacturing a plug-connector, in particular to a plug-connector for connecting external components with electronic components being attached to a printed circuit board.

In a state-of-the-art manufacturing method for manufacturing a plug-connector, it is well known that several adjacent plug contacts are manufactured as a coherent plug contact metal sheet, wherein the plug contacts are connected by small strut-type connection bridges. The manufacturing of the plug contacts as a coherent plug contact metal sheet simplifies the insertion and the positioning of the distantly arranged plug contacts within the plug-connector housing. The plug-connector housing is typically injection-moulded around the plug contacts. For electrically insulating the plug contacts, the connection bridges must be removed before the plug contacts are embedded within the plug-connector housing, because the plug-connector housing restricts the accessibility for removing the connection bridges.

For locking the plug contacts within their specific distant arrangement during and after the connection bridge removing process step, the plug contact metal sheet is embedded in a pre-moulded substrate, which is injection-moulded around the plug contact metal sheet in a first moulding process step without embedding the connection bridges. The connection bridges remain accessible for a removing process step, and the electrically separated plug contacts are secured against any displacement after the connection bridges have been removed. In a second moulding process step, the plug-connector housing is moulded around the pre-moulded substrate and partially around the plug contacts to define the final plug-connector housing.

DE 10 119 412 Al or EP 1 986 290 Bl disclose an example of such a plug-connector.

The pre-moulding process requires an expensive additional mould. Further, the integration of appropriate moulding devices within a serial production results in a relatively complex production line and thereby in relatively high production costs of the plug-connector. Additionally, relatively long process cycle times are provided for producing such a plug-connector resulting from the cooldown process of the pre-moulded substrate after the pre-moulding process.

It is an object of the invention to provide a cost-efficient plug-connector with a relatively simple and short production process.

This object is achieved by a method for manufacturing a plug-connector according to the invention with the features of claim 1 and by a plug-connector according to the invention with the features of claim 9.

A method for manufacturing a plug-connector for an automotive device according to the invention comprises several manufacturing steps. The plug-connector comprises a plug-connector housing, a supporting means with a first supporting means body and a corresponding second supporting means body. The plug-connector further comprises several electroconductive plug contacts, which are adjacently arranged within the plug-connector housing in a side-by-side arrangement defining an insertion plane. The adjacent plug-connectors are electrically insulated from each other defining several conducts for conducting, for example, electrical signals. The plug contacts are provided with a connecting section, with a supporting section and with a terminal section. The terminal section, for example, contacts with an external plug, which can be a male plug or alternatively a female plug. The connecting section is, for example, permanently connected to the conducting paths of a printed circuit board. The supporting section is supported by the supporting means, so that the plug contacts are locked within the supporting means. The supporting means and the plug contacts are integrally over-moulded by the plug-connector housing. Thereby, the supporting means as well as the supporting section are substantially completely embedded within the plug-connector housing, whereas the terminal section and the connecting section are exposed and are not embedded within the plug-connector housing, respectively.

Preferably, at least one of the supporting means bodies is provided with several supporting grooves. The supporting grooves can be shaped such that the plug contacts correspond to the supporting grooves, so that the plug contacts are positively-locked within the supporting grooves.

In a first manufacturing step of a method for manufacturing a plug-connector according to the invention, a pre-shaped plug contact metal sheet is manufactured. The pre-shaped plug contact metal sheet is, for example, defined by a substantially two-dimensional and lattice-like plug contact metal sheet with substantially parallel and adjacently arranged elongated pre-shaped plug contact strips, which are connected by thin transversally oriented connection bridges. The connection bridges are an assembling aid for securing the layout of the plug contact strips and for securing the distance between adjacent plug contact strips during the following manufacturing steps. The distance between the plug contact strips defines the distance between the poles of the final multi-pole plug-connector. In a second manufacturing step of the method for manufacturing a plug-connector according to the invention, the plug contact metal sheet is inserted into one of the supporting means bodies. This supporting means body is preferably provided with supporting grooves corresponding to the plug contact strips of the plug contact metal sheet. The sidewalls of the supporting grooves secure the elongated plug contact strips in both transversal directions within the sheet metal plane.

Within the longitudinal supporting section of the plug contact strips, the plug contact metal sheet is preferably provided with an additional separate positively-locking structure corresponding to a complementary positive-locking structure within the supporting grooves of the supporting means body. This separate positively-locking structure locks the plug contact metal sheet in the plug contact strip's longitudinal direction against a translational displacement within the sheet metal plane. This longitudinal plug contact direction is within the sheet metal plane oriented substantially perpendicularly to the supporting groove sidewalls. For example, the plug contacts can taper within the supporting section, so that the plug contacts are precisely positioned within the complementary shaped supporting grooves. In addition, for positively locking the plug contact metal strip in both longitudinal directions within the sheet metal plane, some of the plug contact strips can taper in opposite longitudinal directions. The positively locking thereby secures the plug contacts against a translational displacement in any direction within the sheet metal plane.

The supporting means bodies support the plug contact metal sheet within the supporting section of the plug contact strips. The supporting means is defined such that the connection bridges are arranged outside of the supporting means. Thereby, the connection bridges are freely accessible after the plug contact metal sheet has been inserted into the supporting grooves of the supporting means body. In a third manufacturing step of the method for manufacturing a plug-connector according to the invention, the supporting means is assembled by attaching the second supporting means body to the first supporting means body supporting the plug contact metal sheet. The second supporting means body corresponds to the first supporting means body and locks the plug contact metal sheet in place between the supporting means bodies. If the supporting means is provided with supporting grooves, which represents a preferred embodiment of the invention, the pre-shaped plug contact metal sheet is thereby positively locked in all translational directions. Alternatively, the plug contact metal sheet can be fixed by a frictional connection, for example, within a supporting means without any supporting grooves by a pure clamping of the pre-shaped contact plug metal sheet, so that an embodiment without an additional positively-locking structure is also applicable.

For attaching the second supporting means body to the first supporting means body, the two supporting means bodies are, for example, provided with a corresponding complementary fastening mechanism. An exemplary fastening mechanism can be a snap-in locking mechanism, wherein one of the supporting means bodies is provided with a snap-in hook and the other supporting means is provided with a complementary snap-in opening.

In a fourth manufacturing step of the method for manufacturing a plug-connector, the connection bridges connecting the plug contact strips are removed. Since the exposed connection bridges are arranged outside of the supporting means bodies, the connection bridges can be easily removed, for example, by punching. The supporting means is, for example, suitable for supporting the pre-shaped plug contact metal sheet within the punching tool. Alternatively, the pre-shaped plug contact metal sheet is directly supported within the punching tool. During the removal process, the supporting means locks the pre-shaped plug contact metal sheet in place. After the connection bridges have been removed, the supporting means still locks the electrically and mechanically separated plug contacts in place, so that their orientation and their arrangement is still maintained and the pre-assembled plug-connector is ready for the next manufacturing step.

In the fifth manufacturing step of the method for manufacturing a plug-connector, the plug-connector housing is moulded around the pre-assembled plug-connector. In this final manufacturing step, the pre-assembled plug-connector is placed, for example, into an injection-mould of an injection-moulding device. The plug-connector housing is injection-moulded around the pre-assembled plug-connector, so that the pre-assembled plug-connector is embedded within the plug-connector housing. During the moulding process, the plug contacts are locked in place by the supporting means against any displacement, which otherwise could be caused, for example, by the injection pressure of the injection-moulding process. After moulding the plug-connector housing, the supporting means is fully embedded within the plug-connector housing, so that the plug-connector housing completely encloses the supporting means.

In contrast, the electrically separated plug contacts are not fully embedded within the plug-connector housing. Both ends of the plug contacts, namely the connecting section and the terminal section, are still exposed and thereby accessible to connect to a corresponding conductive counterpart for conducting any type of electrical signal or energy. Preferably, the plug-connector housing additionally defines a socket for a complementary-shaped male or female plug-connector for providing an electrical connection, for example, via the terminal section of the plug contacts. In addition, the plug-connector housing can be shaped such that the mechanically sensitive plug contacts are protected from any deformations or damages. The connecting section, for example, can be soldered to the conducting paths of a printed circuit board. Thus, the supporting means substitutes a pre-moulded substrate being applicated in the state-of-the-art manufacturing processes of a plug-connector. The supporting means is a simple and effective production tool, which is cost efficient and which can be produced on stock. With the application of the supporting means, the production line of the plug-connector can be significantly simplified compared to a conventional production line. In addition, the production cycle time of one single plug-connector is drastically reduced, by having one single-step moulding process with one cooldown phase only, so that the production costs of the plug-connector are clearly reduced.

In a preferred embodiment of the invention, an additional manufacturing step is provided within the method for manufacturing a plug-connector according to the invention. Before the removing step and/or before the moulding step the plug contacts are bent. Depending on the final design of the plug-connector or on the geometric composition of the assembly group, the plug contacts are bent out of the sheet metal plane. In particular, the application of the plug-connector at a printed circuit board can require a bending of the plug contacts. Therefore, the plug contact strips of the pre-shaped plug contact metal sheet can be bent, before the connection bridges are removed. This method is in particular suitable, if the plug contact strips are equidirectionally bent at a common bending line. Alternatively, the plug contacts can be bent after the connection bridges have been removed. Another alternative can be a combined removing and forming process, which is in particular suitable, if the connection bridges are removed by a punching process, so that both processes can be realised with one combined punching and bending device in one single working stroke.

In a preferred embodiment of a method for manufacturing a plug-connector according to the invention, the manufacturing step for manufacturing the pre-shaped plug contact metal sheet is provided by punching. With a punching process, such sheet metal parts being provided with a complex contouring can be manufactured easily, precisely and, as a result, cost-efficiently, particularly in a serial production with high quantity. Punching thereby allows a simultaneous manufacturing of numerous plug contact metal sheets within one tool with one single working stroke, resulting in relatively low production costs.

Preferably, the supporting means is made of a plastic material, for example, PBT, PA, PPA or PPS. Such a plastic material is in particular suitable for a supporting means application because of its electrically non-conducting properties. For defining a multi-pole electrical plug, the plug contacts require an electrical insulation from each other for avoiding any type of electrical shortcut between the adjacent plug contacts. This requirement can, in particular, be achieved with a plastic supporting means, which is, in addition, cost-efficiently producible. The application of a pre-processed plastic supporting means allows a significant reduction of the production costs by increasing the production cycle time of the plug-connector in comparison to the application of a pre-moulded substrate for locking the plug contacts in place during the production process. In addition, the plastic supporting means allows an easy application of a fastening mechanism, for example, being defined by a snap-in locking mechanism.

In a preferred embodiment of the invention, the supporting means bodies are connected by a film hinge. The film hinge connects the two supporting means bodies at one longitudinal end of the supporting means to define a one-piece supporting means. In particular during the insertion process, the connected supporting means bodies can be easily assembled or disassembled by folding the supporting means using the film hinge. The other longitudinal end opposite to the film hinge is preferably provided with a fastening mechanism for interlocking the two supporting means bodies and to thereby secure the pre-shaped plug contact metal sheet within the supporting means. Preferably, the supporting means and the plug-connector housing are made of the same identical plastic material. Exemplary materials are listed above. The application of identical materials results in identical material properties of the supporting means and of the plug-connector housing, in particular relating to the electrically non-conductivity, but also relating to thermal properties, like thermal resistance or thermal expansion. As the plug-connector housing is moulded around the supporting means being thereby fully embedded within the plug-connector housing the thermal expansion is in particular an important aspect. For avoiding, for example, any crack formation within the plug-connector housing caused by the thermal expansion of a supporting means being made of a material with a higher thermal expansion coefficient, an identical material pairing is advantageous. In addition, an identical material melting point relieves the bonding of the materials of both the supporting means and the plug-connector housing during the moulding process of the plug-connector housing. By melting the top material layer of the supporting means, the top material layer liquifies and, accordingly mixes with the plastics melt for moulding the plug-connector housing, so that, after cooling down, the materials are merged at the substance level.

A plug-connector for an automotive device according to the invention comprises a plug-connector housing, a supporting means with a first supporting means body and a corresponding second supporting means body. The plug-connector further comprises several electroconductive plug contacts, which are adjacently arranged within the plug-connector housing in a side-by-side arrangement defining an insertion plane. The adjacent plug-connectors are electrically insulated from each other defining several conducts for conducting, for example, electrical signals. The plug contacts are provided with a connecting section, with a supporting section and with a terminal section. The terminal section, for example, contacts with an external plug, which can be a male plug or alternatively a female plug. The connecting section is, for example, permanently connected to the conducting paths of a printed circuit board. The supporting section is supported by the supporting means, so that the plug contacts are locked within the supporting means. The supporting means and the plug contacts are integrally over-moulded by the plug-connector housing. Thereby, the supporting means as well as the supporting section are substantially completely embedded within the plug-connector housing, whereas the terminal section and the connecting section are exposed and are not embedded within the plug-connector housing, respectively.

Preferably, at least one of the supporting means bodies is provided with several supporting grooves. The supporting grooves can be shaped such that the plug contacts correspond to the supporting grooves, so that the plug contacts are positively-locked within the supporting grooves.

Preferably, the plug-connector for an automotive device according to the invention is manufactured by the method for manufacturing a plug-connector according to the invention. Thereby all features of the manufacturing process are used for a plug-connector being manufactured by the method according to the invention.

An embodiment of the invention is described with reference to the enclosed drawings, wherein figure 1 shows a plug-connector according to the invention in a perspective view, wherein the plug-connector housing is shown transparently, figure 2 shows the plug-connector of figure 1 during the insertion step of a method for manufacturing a plug-connector according to the invention in a perspective view, figure 3 shows the plug-connector of figure 1 during the assembly step of a method for manufacturing a plug-connector according to the invention in a perspective view, figure 4 shows the plug-connector of figure 1 after the removing step of a method for manufacturing a plug-connector according to the invention in a perspective view, and figure 5 shows an alternative embodiment of the supporting means according to the invention with a film hinge in a perspective view.

Figure 1 shows a plug-connector 10 defining a terminal plug of a printed circuit board being applicated in an electronic automotive auxiliary device, for example, an electronic water circulation pump. The plug-connector 10 conducts energy as well as signals. The plug-connector 10 comprises a plastic plug-connector housing 15, an elongated block-type supporting means 20 with an upper supporting means body 21 and a lower supporting means body 22. The plug-connector 10 further comprises four electroconductive plug contacts 30A,30B made from four tinny, plane and elongated plug contact strips 3O'A,3O'B. Each plug contact 30A,30B comprises a connecting section 31A,31B, a terminal section 32A,32B and a supporting section 33A,33B, the supporting section 33A,33B defines a sheet metal plane and connects the connecting section 31A,31B and the terminal section 32A,32B. Both the connecting section 31A,31B and the terminal section 32A,32B extend each from one of the free longitudinal ends of the plug contacts 30A,30B to the supporting section 33A,33B.

The connecting section 31A,31B and the terminal section 32A,32B have been bent out of the sheet metal plane orthogonally to the same side. The terminal section 32A,32B of each plug contact is identically shaped. At the terminal side of the plug-connector 10, all four plug contacts 30A,30B have been bent at a common bending line, so that all terminal sections 32A,32B of every plug contact 30A,30B lie on the same transversal plug contact plane and are all of the same length. At the other end of the plug-connector 10, the connecting section 31A of the two outer distal plug contacts 30A is not identical to the connecting section 31B of the two inner proximal plug contacts 30B. The plug contact width of the connecting section 31A of the two outer power supplying plug contacts 30A is transversally increased by approximately the double of the width of the connecting section 31B of the two inner signal conducting plug contacts 30B. The free end of the connecting section 31A of the outer plug contact 30A is provided with two parallel and distant contact pins 34A, which extend co-planar to the connecting section 31A at its both longitudinal edges.

At the connecting side, the supporting section 33A of the two outer plug contacts 30A is longitudinally larger than the supporting section 33B of the inner plug contacts 30B, so that at the connection side the connecting sections 31A of the outer plug contacts 30A and the connecting sections 31B of the inner plug contacts 30B do not lie in the same transversal plane as the terminal sections 32A,32B at the terminal side. However, the connecting sections 31A,31B of all four plug contacts 30A,30B are of the same length. Each of the free ends of the connecting sections 31B of the two inner plug contacts 30B is provided with a single contact pin 34B extending co-planar to the connecting section 31B and centrically from the end surface of the connecting section 31B. The transversal width of all of the contact pins 34A,34B is about one third smaller than the width of the connecting section 31B of the inner plug contacts 30B. The length of all of the contact pins 34A,34B is about one third of the length of each of the connecting sections 31A,31B.

The plug contacts 30A,30B are made of a plane lattice-like pre-shaped plug contact metal sheet 35, shown in figure 2. The plug contact metal sheet 35 comprises four tinny elongated and parallel plug contact strips 3O'A,3O'B being transversally connected by thin strut-type connection bridges 36, every two adjacent plug contact strips 3O'A,3O'B being connected by two connection bridges 36. The connection bridges 36 are arranged substantially at the longitudinal ends of the supporting sections 33A,33B being defined by the bending lines B1,B2,B3 of the plug contact strips 3O'A,3O'B. The plug contact metal sheet 35 is made of a particularly electroconductive material, for example, copper and is manufactured by punching, which represents a first manufacturing step of a method for manufacturing the plug-connector 10.

The lattice-like plug contact metal sheet 35 is during the manufacturing process of the plug-connector 10 supported by the block-type supporting means 20. Therefore, the supporting means bodies 21,22 are separated and the plug contact metal sheet 35 is inserted into the lower supporting means body 22 being provided with four supporting grooves 25. This insertion process represents the second manufacturing step of the method for manufacturing the plug-connector 10. The lower supporting means body 22 supports the plug contact metal sheet 35 within the supporting sections 33A,33B of each plug contact strip 3O'A,3O'B between the connection bridges 36. The sidewalls of the supporting grooves 25 positively lock the plug contact metal sheet 35 against a translational displacement in the transversal plug contact strip direction within the sheet metal plane.

For positively locking the plug contact metal sheet 35 in the longitudinal plug contact strip direction within the sheet metal plane, the plug contact strips 3O'A,3O'B are tapered within the supporting section 33A,33B. The supporting grooves 25 are correspondingly and complementary shaped, wherein the tapering direction of the inner plug contact strips 30'B is oriented opposite to the tapering direction of the outer plug contact strips 30'A. The inner plug contact strips 30'B taper in the first longitudinal direction, i.e. taper in direction of the connecting section 31A,31B, whereas the outer plug contact strips 30'B taper in the other opposite longitudinal direction, namely in direction of the terminal section 32A,32B. The supporting grooves 25 thereby lock the plug contact metal sheet 35 in all translational directions within the sheet metal plane.

For fixing the plug contact strips 3O'A,3O'B within the supporting grooves 25 the supporting means is assembled by mounting the upper supporting means body 21 to the lower supporting means body 22, so that the plug contact metal sheet 35 is locked in place between the two supporting means bodies 21,22. This assembly step represents the third step of the method for manufacturing the plug-connector 10, shown in figure 3. For attaching the upper supporting means body 21 to the lower supporting means body 22, both longitudinal ends of both the upper supporting means body 21 and the lower supporting means body are provided with complementary elements of a snap-in locking mechanism. The upper supporting means body 21 is provided at each of both longitudinal ends with a snap-in hook 23 and the lower supporting means body 22 is provided at each of both longitudinal ends with a corresponding snap-in opening 24, shown in figure 2.

After locking the plug contact metal sheet 35 in place using the supporting means 20, the connection bridges 36 are removed by punching. This removing process represents the fourth step of the method for manufacturing the plug-connector 10. As a result, the plug contact strips 3O'A,3O'B are mechanically and electrically separated to provide separately conducting plug contacts 30A,30B. The assembled supporting means 20 and the electrically insulated plug contacts 30A,30B together define a pre-assembled plug-connector 10', shown in figure 4.

After the connection bridges 36 have been removed, the plug contact strips 3O'A,3O'B are bent equidirectionally and perpendicularly to the same side of the sheet metal plane. In the final manufacturing step of the method for manufacturing the plug-connector 10, namely the moulding step, the plastic plug-connector housing 15 is injection-moulded around the pre-assembled plug-connector 10'. Thereby the plastic supporting means 20 is completely embedded within the plug-connector housing 15. For providing a material-bonded connection between the supporting means 20 and the plug-connector housing 15 during the injection-moulding process of the plug-connector housing 15, the supporting means 20 and the plug-connector housing 15 are made of an identical plastic material.

Besides the embedding of the supporting means 20, the supporting sections 33A,33B are also embedded within the plug-connector housing 15. For ensuring the accessibility of the terminal section 32A,32B of the plug contacts 30A, 30B the plug-connector housing 15 is provided with a rectangular access opening 16 defining a socket 18 for plugging a corresponding plug of an electronic component. The terminal sections 32A,32B of the plug contacts 30A,30B are exposed within the socket 18 for providing a conductive connection with the plug contacts of the complementary plug. At the connecting side, the plug-connector housing 15 ends within the half of the length the connecting section 32A,32B of the plug contacts 30A,30B to remain the contact pins 34A,34B accessible for being connected to a printed circuit board.

Figure 5 shows an alternative embodiment of the supporting means 20' comprising an upper supporting means body 21' and a lower supporting means body 22', wherein the supporting means bodies 21', 22' are at one longitudinal end permanently connected by a film hinge. This foldable supporting means 20' is at its other longitudinal end provided with a snap-in locking mechanism, wherein the lower supporting means body 22' is provided with a snap-in opening 24' and the upper supporting means body 21' is provided with a corresponding and complementary snap-in hook 23'. After the insertion of a plug contact metal sheet 35 into the unfolded and open supporting means 20', the upper supporting means body 21' is folded onto the lower supporting means body 22' and the snap-in hook 23' is inserted into the complementary snap-in opening 24', so that the two supporting means bodies 21', 22' are connected and the supporting means 20' is closed. This alternative supporting means 20' can additionally be provided with all the features of the supporting means 20 of the first embodiment according to the invention.