HIGH-CURRENT MODULE FOR CHARGING PLUG-IN CONNECTOR PART

A module for a plug-in connector part includes: a sleeve; at least two busbars, arranged in the sleeve, to each of which a plug contact and at least one load line are connectable or connected; and at least one heat capacity element mounted in or on the sleeve. The module is mountable on the plug-in connector part.

CROSS-REFERENCE TO PRIOR APPLICATION

Priority is claimed to German Patent Application No. DE 10 2021 101 528.6, filed on Jan. 25, 2021, the entire disclosure of which is hereby incorporated by reference herein.

FIELD

The invention relates to a module for a plug-in connector part, a plug-in connector part, and a method for producing such a plug-in connector part.

BACKGROUND

Particularly in the field of e-mobility, the highest demands with respect to the current-carrying capacity and the associated thermal loads exist for plug-in connector parts and associated cable assemblies. In addition to the cables, the plug-in connectors are regularly exposed to high charging currents—for example, of several hundred amperes. These high currents are supposed to be transmitted with the lowest possible power loss. Even higher currents are being considered for the future. Against this background, it is worth noting that the power loss rises as the square of the current. This regularly results in the problem of designing components which provide as good an electrical performance as possible with a manageable overall size. In the case of electromechanical connections, this typically means as small an electrical resistance as possible, with simultaneously controlled heating.

This has often been successfully achieved with actively-cooled plug connectors and charging cables. However, the technical effort that is usually required for this is reflected in the costs and the effort for the production of the actively-cooled components of the corresponding charging devices.

To date, there have been no suitable solutions—particularly in a charging current range in which active cooling is not yet economical, but a conventional construction with crimped contacts potentially heats up too quickly, e.g., in a range around 300 A.

SUMMARY

In an embodiment, the present invention provides a module for a plug-in connector part, comprising: a sleeve; at least two busbars, arranged in the sleeve, to each of which a plug contact and at least one load line are connectable or connected; and at least one heat capacity element mounted in or on the sleeve, wherein the module is mountable on the plug-in connector part.

DETAILED DESCRIPTION

In an embodiment, the present invention provides a plug-in connector part which allows the lowest possible power loss and is particularly easy to produce.

Accordingly, a module for a plug-in connector part is specified, having a sleeve, at least two busbars, arranged in the sleeve, to each of which a plug contact and at least one load line can be connected or are connected, and at least one heat capacity element mounted in or on the sleeve. The (in particular, pre-assembled) module can be mounted on—in particular, in—the plug-in connector part.

In this way, a module, e.g., a pre-mounted and pre-testable module, is provided which can be installed in a particularly easy manner in the plug-in connector part and thus considerably simplify the production. The busbars can be designed with a particularly large cross-section and can thus significantly reduce the power loss. The heat capacity element enables the temperature rise to be delayed. The combination of the busbars with the heat capacity element and the installation in the module make it possible, in a particularly simple and easily producible structure, to limit the temperature rise to sufficiently low values over a typical charging period for charging the battery of an electric vehicle. The heat capacity element or the heat capacity elements is/are configured to absorb heat from the busbars. The heat capacity element(s) has/have a large thermal capacity and is/are thermally connected to one or both busbars so that heat can be introduced from the busbar(s) into the respective heat capacity element and absorbed there. This is based upon the idea of providing an increased heat capacity on a plug-in connector part, on the basis of which the heating of the plug-in connector part can be slowed down.

The connector part may be a high-current and/or high-voltage connector part. The module is in particular a high-current module. For example, the plug-in connector part is designed to conduct electrical currents of approximately 300 A or at least 300 A and/or have a power of approximately 135 kW or more than 135 kW.

For example, the at least one heat capacity element is produced from a material having a high specific heat capacity—for example, a specific heat capacity greater than 0.5 kJ/(kg*K), and in particular greater than 1.0 kJ/(kg*K). Alternatively or additionally, the material has a high thermal conductivity—for example above 50 W/(m*K), and in particular above 100 W/(m*K). This allows the heat to be efficiently conducted away from the busbars.

Optionally, the at least one heat capacity element is mounted on one of the busbars by means of a housing part—for example, made of an insulation material. As a result, electrical insulation of both parts with respect to other components and a fastening to one another is simultaneously made possible.

For example, the at least one heat capacity element lies flat against one of the busbars. This enables good heat transfer. The at least one heat capacity element can be in contact with the busbar—alternatively, with the interposition of an—in particular, planar—insulator. For example, the busbars and/or the heat capacity element(s) have a rectangular cross-section, at least in sections. Plane surfaces of the at least one heat capacity element and of the busbar(s) that are parallel to one another can thereby rest against one another.

In one embodiment, at least two heat capacity elements are provided. Optionally, the at least two busbars are arranged between the two heat capacity elements. This enables a particularly efficient absorption of heat.

For example, the module comprises at least one interface for mounting the pre-assembled module on the plug-in connector part. The interface is formed, for example, by a mounting adapter which, in one embodiment, closes an opening of the sleeve and, optionally, has an opening for each of the plug contacts. The mounting adapter can thus be mounted on a part—for example, a housing part—of the plug-in connector.

The busbars are mounted, for example, on an insulating support arranged in the sleeve. This enables further simplified production, since the insulating support with electrical insulation of the busbars from one another and the holder thereof fulfills a dual function. The insulating support has, for example, at least in sections, an H-shaped cross-section.

It can be provided that each of the busbars have a larger cross-section than one of the load lines connected or connectable thereto, or a cross-section greater than the sum of the cross-sections of several connected or connectable load lines—in particular, at least a cross-section that is twice as large (as the load line or load lines).

The at least two busbars can each have two sections which are at an angle to one another. Thus, the busbars can extend through an ergonomically-shaped plug-in connector part—in particular, in the form of a charging plug.

The sleeve can form an interior space, wherein the interior space is sealed—in particular, against water and/or dust. It is thus made possible for the module to be secured in its own right at least in sections against environmental influences and/or with respect to other lines or other components of the plug-in connector part.

According to one aspect, a plug-in connector part is provided for connecting to a mating connector part. The plug-in connector part comprises a housing and at least one module, arranged in the housing, according to any embodiment described herein.

The plug-in connector part may in particular be designed as a charging plug-in connector part—in particular, as a vehicle charging plug.

According to one aspect, a method for producing a plug-in connector part for connecting to a mating connector part is provided—in particular, the plug-in connector part according to any embodiment described herein. The method comprises assembling at least two busbars and at least one heat capacity element to form a pre-assembled module; and mounting the module in a housing of the plug-in connector part.

The idea forming the basis of the invention shall be explained in more detail below on the basis of the exemplary embodiment shown in the figures. The following are shown:

FIG. 1shows an electrically-powered vehicle5, also referred to as an electric vehicle, and a charging station6, which serves to charge the vehicle5. For this purpose, a plug-in connector part2in the form of a manually-pluggable vehicle charging plug is provided for detachable electrical connection to a mating connector part4in the form of a vehicle charging socket. Together, the plug-in connector part2and the mating connector part4form a plug connection. The charging station6is designed to provide a charging current in the form of a direct current (alternatively or additionally, an alternating current). The charging station6can be electrically connected to the vehicle5via a cable3, which is connected at one end to the charging station6and at another end to the plug-in connector part2. Optionally, the cable3has a plug-in connector part2at each of the two ends, of which one can be detachably connected to the mating connector part4on the vehicle5and another to a corresponding mating connector part at the charging station6.

As can be seen from the enlarged view inFIG. 2, the plug-in connector part2has plug-in sections22,23, by means of which the plug-in connector part2can be brought into plug-in engagement with the associated mating connector part4in order to transmit charging currents from the charging station6to the vehicle5.

The plug-in connector part2has a plurality of contact elements on its plug-in sections22,23. For example, two plug contacts21A,21B for transmitting the charging current in the form of a direct current can be arranged on the plug-in section22, while, for example, three or five contact elements for providing load contacts are provided on the plug-in section23in order to transmit an (e.g., multi-phase) alternating current and/or to provide contacts for data transmission. In the specific exemplary embodiment shown inFIG. 2of a plug-in connector part2, the plug contacts21A,21B are arranged on a lower plug-in section22within two contact domes, said plug contacts being used for transmitting a charging current in the form of a direct current.

As shown schematically inFIG. 2, the plug-in contacts21A,21B on the plug-in section22of the plug-in connector part2can be brought into plug-in engagement with counter-contact elements40in the form of contact pins on sides of the mating connector part4in an insertion direction E in order to electrically contact the plug contacts21A,21B with the counter-contact elements40.

The plug-in connector part2further comprises a housing20, which forms a handle202. A user can grip the plug-in connector part2on the handle202and attach said plug-in connector part to the mating connector part4or pull it off

Load lines30, which serve for transmitting a charging current through the plug-in connector part2, are guided in the cable3connected to the plug-in connector part2, as can be seen, for example, fromFIG. 3.

In order to enable a rapid charging of the electric vehicle5, e.g., in the context of a so-called rapid-charging process, the transmittable charging currents have a high amperage—for example, an amperage on the order of magnitude of 300 A or higher. Such high charging currents can generally lead to thermal losses on a plug-in connector part and, consequently, to a heating of the plug-in connector part.

The plug-in connector part2is not actively cooled. In particular, it has no channels for liquid cooling. In order to significantly slow down the heating of the plug-in connector part2, the plug-in connector part2in the present case comprises a high-current module, which is referred to below as module1for short and will be described in detail below. The module1is a self-contained structural unit and can be installed pre-assembled in the housing20of the plug-in connector part2. Before being installed in the housing20of the plug-in connector part2, the module1can be pre-checked for correct function.

FIGS. 4 and 5show the plug-in connector part2, wherein an upper housing part201forming the handle202(seeFIGS. 2 and 3) is removed from a lower housing part200so that an interior of the plug-in connector part2is visible.FIG. 6shows the module1separately, together with the plug contacts21A,21B connected thereto (screwed with screw connections of module1) and load lines30. Optionally, the module1(in particular, at least for plug contacts21A,21B mounted thereon) is closed in a liquid-tight manner so that no liquid can penetrate into the module1.

The module1comprises a first section16and a second section17. The plug contacts21A,21B are mounted on the first section16. The load lines30are connected to the second section17. The first section16and the second section17run at an angle to one another. In the present case, the first section16is at an obtuse angle to the second section17. In the assembled state of the plug-in connector part2, the module1is arranged completely, or at least almost completely, in the interior of the housing20.

FIGS. 7-9show the individual parts of the module1. The module1comprises a sleeve10. The sleeve10is flexible (e.g., made of rubber) or rigid. The sleeve10defines an interior space100. The interior space100is accessible at two ends of the sleeve10facing away from one another. In the example shown, the sleeve10is formed in one piece.

The module1further comprises two busbars11A,11B and several (in the present case, four) heat capacity elements12A-12D. The busbars11A,11B have a large cross-section—in particular, a substantially larger cross-section than the load line30connected in each case thereto—or, as in the example shown, in the case of several load lines30(in the present case, two) each connected to a busbar11A,11B, a larger or substantially larger cross-section than the sum of the cross-sections of the load lines30connected thereto. By using the busbars11A,11B, a particularly low electrical resistance can be achieved.

The busbars11A,11B each have a first section110and a second section111. The first section110and the second section111are in each case extended longitudinally and, like the two sections16,17of the module1, are, as a whole, at an angle to each other. The first section110is adjoined by a mounting section112(at the end of the first section110facing away from the second section111). A threaded bore is provided on the mounting section112, on which one of the plug contacts21A,21B can be mounted in each case.

Receptacles113for the load lines30are formed on the second section111(in the present case, at the end of the second section111facing away from the first section110); see, in particular,FIGS. 8 and 9. In the present example, these receptacles113are formed in the shape of a trough—in particular, for soldering the load lines30—wherein, alternatively, flat receptacles are also conceivable—for example, for ultrasonic welding of the load lines30. Each busbar11A,11B comprises two such trough-shaped receptacles113. A load line30can be connected—in particular, connected by material bonding—to each of the receptacles113. In the present case, in the method for producing the module1and the plug-in connector part2, the load lines30are each inserted into the corresponding receptacles113and thus welded—for example, by means of ultrasonic welding.

The busbars11A,11B each have a rectangular cross-section. The busbars11A,11B are each formed in one piece—in particular, also of the same material. For example, the busbars11A,11B are made of copper. Optionally, the busbars11A,11B are punched and bent for production.

The heat capacity elements12A-12D are produced, for example, from a material having a specific heat capacity of above 0.5 kJ/(kg*K), and in particular above 1.0 kJ/(kg*K). Furthermore, the material has a high thermal conductivity, e.g., above 50 W/(m*K), and in particular above 100 W/(m*K). The heat capacity elements12A-12D are formed in a block shape. Each of the heat capacity elements12A-12D is formed in one piece. In the assembled state (see, in particular,FIG. 10), the heat capacity elements12A-12D each lie flat against one of the busbars11A,11B. The heat capacity elements12A-12D are thermally coupled to the busbars11A,11B. Optionally, the heat capacity elements12A-12D are electrically insulated from the busbars11A,11B—for example, by intermediate layer of an insulator. The heat capacity elements12A-12D can, in total, have a weight which, for example, corresponds to at least 10%—in particular, at least50%—of the sum of the weights of the busbars11A,11B. As a result, a substantial slowing of the heating of the busbars11A,11B and of the plug-in connector part2is possible. The heat capacity elements12A-12D of the plug-in connector part2can be dimensioned such that, during a typical charging process, the heating remains below a predetermined limit—for example, below 50 K.

In the assembled state, the busbars11A,11B are electrically insulated from one another by an insulating support13. For this purpose, the insulating support13comprises a separating section130, which is arranged between the two busbars11A,11B in the assembled state. As can be seen in particular with reference toFIG. 10, the separating section130is in planar contact with each of the two busbars11A,11B. The insulating support13also serves to hold the two busbars11A,11B and the heat capacity elements12A-12D. For this purpose, the insulating support13has several screw domes133on the separating section130. The busbars11A,11B have matching holes with which the busbars11A,11B can be fitted onto the screw domes133(and are in the assembled state). In this case, the heat capacity elements12A-12D are inserted into receptacles of housing parts15A,15B and are attached to the busbars11A,11B by means of said housing parts15A,15B. Screws16engage through bores in the housing parts15A,15B and will be or are screwed to the screw domes133(see, in particular,FIGS. 9 and 11). In the assembled state, a heat capacity element12A,12C in each case lies on the first section110of one of the busbars11A,11B, and a heat capacity element12B,12D in each case lies on the second section of one of the busbars11A,11B. The housing parts15A,15B are made from an electrically-insulating material.

The insulating support13further comprises two transverse parts131,132. The transverse parts131,132each protrude at right angles from the separating section130. In cross-section, the transverse parts131,132and the separating section130are arranged as an H-shape; see, for example,FIG. 10. The two transverse parts131,132extend in parallel to one another. It can be seen fromFIG. 10that the busbars11A,11B are arranged between two, opposite (and identical or mirror-inverted in design) heat capacity elements12A-12B. The housing parts15A,15B and the insulating support13surround the busbars11A,11B and the heat capacity elements12A-12D in an electrically-insulating manner. It can be seen fromFIG. 11how the housing parts15A,15B are screwed to the screw domes133of the insulating support13by means of the screws16.

During assembly, for example, the busbars11A,11B and the heat capacity elements12A-12D are first mounted on the insulating support13—in the present case, screwed thereto—by means of the housing parts15A,15B, forming a mounted assembly. The mounted assembly is shown inFIG. 12, wherein the insulating support13only is not shown.FIG. 13shows a cross-sectional view of the sleeve10with the interior space100, which is accessible at one end via an opening101, and at the other end via a feedthrough section102for the load lines30. The mounted assembly is then arranged in the sleeve10, e.g., inserted through the opening101—optionally, with the already-connected load lines30. Alternatively, a sleeve, which is initially open, is placed around the mounted assembly and then closed. If the module1is fully assembled and the load lines30are connected thereto, the load lines30extend through the feedthrough section102—optionally, in a fluid-tight manner. Optionally, the feedthrough section102comprises a suitable passage opening for each load line30.

In the pre-assembled module1, the two busbars11A,11B and the heat capacity elements12A-12D are thus arranged in the sleeve10.

Furthermore, the module1comprises a mounting adapter14; see, in particular,FIGS. 6 and 7. The mounting adapter14has two holes—in each case, one for one of the plug contacts21A,21B. In the assembled state of the module1, the mounting adapter14is mounted on the opening101of the sleeve10—optionally, with a fluid-tight connection—e.g., plugged thereon. The module1can be self-contained and also sealed.

FIG. 14shows the module1with the load lines30connected thereto, wherein it is also already mounted on a part of the plug-in connector part2—in the present case, on a connector face part24of the plug-in connector part2, which forms the plug sections22,23. For this purpose, the module1with the mounting adapter14is connected to the part of the plug-in connector part2(i.e., here, the connector face part24). In the example shown, the part and the mounting adapter14have compatible conical sections which facilitate an exact adjustment. Consequently, in production, the plug contacts21A,21B are then each screwed to the corresponding busbar11A,11B; see, in particular, the enlarged view inFIG. 15. This facilitates simple production. In addition, the typically mechanically highly-stressed plug contacts21A,21B can be easily replaced. The mounting adapter14is thus formed to fit to a part of the plug-in connector part2. The mounting adapter14thus serves as an interface for mounting the pre-assembled module1on the plug-in connector part2.

FIG. 16shows how the mounting adapter14is fastened to the sleeve10—specifically, to the opening101of the sleeve10, and, in fact, by means of a latching connection. The mounting adapter14has a circumferential projection which engages in a circumferential groove of the sleeve10.

FIG. 17shows the feedthrough section102of the sleeve10with the load lines30fed through. The feedthrough section102is designed in the form of a grommet (e.g., a rubber grommet) and adjoins the load lines30in sections.

LIST OF REFERENCE SIGNS