Patent Publication Number: US-2022234455-A1

Title: High-current module for charging plug-in connector part

Description:
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. 
     DE 10 2016 107 409 A1 proposes a plug-in connector part with active cooling. DE 10 2016 105 308 A1 describes a vehicle charging socket with thermal capacity elements. 
     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. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Subject matter of the present disclosure will be described in even greater detail below based on the exemplary figures. All features described and/or illustrated herein can be used alone or combined in different combinations. The features and advantages of various embodiments will become apparent by reading the following detailed description with reference to the attached drawings, which illustrate the following: 
         FIG. 1  is a view of a vehicle with a plug-in connector part, designed as a vehicle charging plug, which is connected to a charging station via a cable; 
         FIGS. 2 and 3  are views of the plug-in connector part, designed as a vehicle charging plug, according to  FIG. 1 ; 
         FIGS. 4 and 5  show parts of the connector part according to  FIGS. 2 and 3 ; 
         FIG. 6  is a view of a module of the plug-in connector part of  FIGS. 2 and 3 ; 
         FIGS. 7 through 9  show parts of the plug-in connector part according to  FIGS. 2 and 3  in exploded views; 
         FIGS. 10 and 11  are cross-sectional views of the connector part according to  FIG. 6 ; and 
         FIGS. 12 and 13  are views of parts of the module according to  FIG. 6 ; 
         FIGS. 14 and 15  are cross-sectional views of the module according to  FIG. 6  mounted on parts of the plug-in connector part according to  FIGS. 2 and 3 ; and 
         FIGS. 16 and 17  are views of the module according to  FIG. 6 . 
     
    
    
     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. 1  shows an electrically-powered vehicle  5 , also referred to as an electric vehicle, and a charging station  6 , which serves to charge the vehicle  5 . For this purpose, a plug-in connector part  2  in the form of a manually-pluggable vehicle charging plug is provided for detachable electrical connection to a mating connector part  4  in the form of a vehicle charging socket. Together, the plug-in connector part  2  and the mating connector part  4  form a plug connection. The charging station  6  is designed to provide a charging current in the form of a direct current (alternatively or additionally, an alternating current). The charging station  6  can be electrically connected to the vehicle  5  via a cable  3 , which is connected at one end to the charging station  6  and at another end to the plug-in connector part  2 . Optionally, the cable  3  has a plug-in connector part  2  at each of the two ends, of which one can be detachably connected to the mating connector part  4  on the vehicle  5  and another to a corresponding mating connector part at the charging station  6 . 
     As can be seen from the enlarged view in  FIG. 2 , the plug-in connector part  2  has plug-in sections  22 ,  23 , by means of which the plug-in connector part  2  can be brought into plug-in engagement with the associated mating connector part  4  in order to transmit charging currents from the charging station  6  to the vehicle  5 . 
     The plug-in connector part  2  has a plurality of contact elements on its plug-in sections  22 ,  23 . For example, two plug contacts  21 A,  21 B for transmitting the charging current in the form of a direct current can be arranged on the plug-in section  22 , while, for example, three or five contact elements for providing load contacts are provided on the plug-in section  23  in order to transmit an (e.g., multi-phase) alternating current and/or to provide contacts for data transmission. In the specific exemplary embodiment shown in  FIG. 2  of a plug-in connector part  2 , the plug contacts  21 A,  21 B are arranged on a lower plug-in section  22  within two contact domes, said plug contacts being used for transmitting a charging current in the form of a direct current. 
     As shown schematically in  FIG. 2 , the plug-in contacts  21 A,  21 B on the plug-in section  22  of the plug-in connector part  2  can be brought into plug-in engagement with counter-contact elements  40  in the form of contact pins on sides of the mating connector part  4  in an insertion direction E in order to electrically contact the plug contacts  21 A,  21 B with the counter-contact elements  40 . 
     The plug-in connector part  2  further comprises a housing  20 , which forms a handle  202 . A user can grip the plug-in connector part  2  on the handle  202  and attach said plug-in connector part to the mating connector part  4  or pull it off 
     Load lines  30 , which serve for transmitting a charging current through the plug-in connector part  2 , are guided in the cable  3  connected to the plug-in connector part  2 , as can be seen, for example, from  FIG. 3 . 
     In order to enable a rapid charging of the electric vehicle  5 , 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 part  2  is 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 part  2 , the plug-in connector part  2  in the present case comprises a high-current module, which is referred to below as module  1  for short and will be described in detail below. The module  1  is a self-contained structural unit and can be installed pre-assembled in the housing  20  of the plug-in connector part  2 . Before being installed in the housing  20  of the plug-in connector part  2 , the module  1  can be pre-checked for correct function. 
       FIGS. 4 and 5  show the plug-in connector part  2 , wherein an upper housing part  201  forming the handle  202  (see  FIGS. 2 and 3 ) is removed from a lower housing part  200  so that an interior of the plug-in connector part  2  is visible.  FIG. 6  shows the module  1  separately, together with the plug contacts  21 A,  21 B connected thereto (screwed with screw connections of module  1 ) and load lines  30 . Optionally, the module  1  (in particular, at least for plug contacts  21 A,  21 B mounted thereon) is closed in a liquid-tight manner so that no liquid can penetrate into the module  1 . 
     The module  1  comprises a first section  16  and a second section  17 . The plug contacts  21 A,  21 B are mounted on the first section  16 . The load lines  30  are connected to the second section  17 . The first section  16  and the second section  17  run at an angle to one another. In the present case, the first section  16  is at an obtuse angle to the second section  17 . In the assembled state of the plug-in connector part  2 , the module  1  is arranged completely, or at least almost completely, in the interior of the housing  20 . 
       FIGS. 7-9  show the individual parts of the module  1 . The module  1  comprises a sleeve  10 . The sleeve  10  is flexible (e.g., made of rubber) or rigid. The sleeve  10  defines an interior space  100 . The interior space  100  is accessible at two ends of the sleeve  10  facing away from one another. In the example shown, the sleeve  10  is formed in one piece. 
     The module  1  further comprises two busbars  11 A,  11 B and several (in the present case, four) heat capacity elements  12 A- 12 D. The busbars  11 A,  11 B have a large cross-section—in particular, a substantially larger cross-section than the load line  30  connected in each case thereto—or, as in the example shown, in the case of several load lines  30  (in the present case, two) each connected to a busbar  11 A,  11 B, a larger or substantially larger cross-section than the sum of the cross-sections of the load lines  30  connected thereto. By using the busbars  11 A,  11 B, a particularly low electrical resistance can be achieved. 
     The busbars  11 A,  11 B each have a first section  110  and a second section  111 . The first section  110  and the second section  111  are in each case extended longitudinally and, like the two sections  16 ,  17  of the module  1 , are, as a whole, at an angle to each other. The first section  110  is adjoined by a mounting section  112  (at the end of the first section  110  facing away from the second section  111 ). A threaded bore is provided on the mounting section  112 , on which one of the plug contacts  21 A,  21 B can be mounted in each case. 
     Receptacles  113  for the load lines  30  are formed on the second section  111  (in the present case, at the end of the second section  111  facing away from the first section  110 ); see, in particular,  FIGS. 8 and 9 . In the present example, these receptacles  113  are formed in the shape of a trough—in particular, for soldering the load lines  30 —wherein, alternatively, flat receptacles are also conceivable—for example, for ultrasonic welding of the load lines  30 . Each busbar  11 A,  11 B comprises two such trough-shaped receptacles  113 . A load line  30  can be connected—in particular, connected by material bonding—to each of the receptacles  113 . In the present case, in the method for producing the module  1  and the plug-in connector part  2 , the load lines  30  are each inserted into the corresponding receptacles  113  and thus welded—for example, by means of ultrasonic welding. 
     The busbars  11 A,  11 B each have a rectangular cross-section. The busbars  11 A,  11 B are each formed in one piece—in particular, also of the same material. For example, the busbars  11 A,  11 B are made of copper. Optionally, the busbars  11 A,  11 B are punched and bent for production. 
     The heat capacity elements  12 A- 12 D 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 elements  12 A- 12 D are formed in a block shape. Each of the heat capacity elements  12 A- 12 D is formed in one piece. In the assembled state (see, in particular,  FIG. 10 ), the heat capacity elements  12 A- 12 D each lie flat against one of the busbars  11 A,  11 B. The heat capacity elements  12 A- 12 D are thermally coupled to the busbars  11 A,  11 B. Optionally, the heat capacity elements  12 A- 12 D are electrically insulated from the busbars  11 A,  11 B—for example, by intermediate layer of an insulator. The heat capacity elements  12 A- 12 D can, in total, have a weight which, for example, corresponds to at least 10%—in particular, at least  50 %—of the sum of the weights of the busbars  11 A,  11 B. As a result, a substantial slowing of the heating of the busbars  11 A,  11 B and of the plug-in connector part  2  is possible. The heat capacity elements  12 A- 12 D of the plug-in connector part  2  can 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 busbars  11 A,  11 B are electrically insulated from one another by an insulating support  13 . For this purpose, the insulating support  13  comprises a separating section  130 , which is arranged between the two busbars  11 A,  11 B in the assembled state. As can be seen in particular with reference to  FIG. 10 , the separating section  130  is in planar contact with each of the two busbars  11 A,  11 B. The insulating support  13  also serves to hold the two busbars  11 A,  11 B and the heat capacity elements  12 A- 12 D. For this purpose, the insulating support  13  has several screw domes  133  on the separating section  130 . The busbars  11 A,  11 B have matching holes with which the busbars  11 A,  11 B can be fitted onto the screw domes  133  (and are in the assembled state). In this case, the heat capacity elements  12 A- 12 D are inserted into receptacles of housing parts  15 A,  15 B and are attached to the busbars  11 A,  11 B by means of said housing parts  15 A,  15 B. Screws  16  engage through bores in the housing parts  15 A,  15 B and will be or are screwed to the screw domes  133  (see, in particular,  FIGS. 9 and 11 ). In the assembled state, a heat capacity element  12 A,  12 C in each case lies on the first section  110  of one of the busbars  11 A,  11 B, and a heat capacity element  12 B,  12 D in each case lies on the second section of one of the busbars  11 A,  11 B. The housing parts  15 A,  15 B are made from an electrically-insulating material. 
     The insulating support  13  further comprises two transverse parts  131 ,  132 . The transverse parts  131 ,  132  each protrude at right angles from the separating section  130 . In cross-section, the transverse parts  131 ,  132  and the separating section  130  are arranged as an H-shape; see, for example,  FIG. 10 . The two transverse parts  131 ,  132  extend in parallel to one another. It can be seen from  FIG. 10  that the busbars  11 A,  11 B are arranged between two, opposite (and identical or mirror-inverted in design) heat capacity elements  12 A- 12 B. The housing parts  15 A,  15 B and the insulating support  13  surround the busbars  11 A,  11 B and the heat capacity elements  12 A- 12 D in an electrically-insulating manner. It can be seen from  FIG. 11  how the housing parts  15 A,  15 B are screwed to the screw domes  133  of the insulating support  13  by means of the screws  16 . 
     During assembly, for example, the busbars  11 A,  11 B and the heat capacity elements  12 A- 12 D are first mounted on the insulating support  13 —in the present case, screwed thereto—by means of the housing parts  15 A,  15 B, forming a mounted assembly. The mounted assembly is shown in  FIG. 12 , wherein the insulating support  13  only is not shown.  FIG. 13  shows a cross-sectional view of the sleeve  10  with the interior space  100 , which is accessible at one end via an opening  101 , and at the other end via a feedthrough section  102  for the load lines  30 . The mounted assembly is then arranged in the sleeve  10 , e.g., inserted through the opening  101 —optionally, with the already-connected load lines  30 . Alternatively, a sleeve, which is initially open, is placed around the mounted assembly and then closed. If the module  1  is fully assembled and the load lines  30  are connected thereto, the load lines  30  extend through the feedthrough section  102 —optionally, in a fluid-tight manner. Optionally, the feedthrough section  102  comprises a suitable passage opening for each load line  30 . 
     In the pre-assembled module  1 , the two busbars  11 A,  11 B and the heat capacity elements  12 A- 12 D are thus arranged in the sleeve  10 . 
     Furthermore, the module  1  comprises a mounting adapter  14 ; see, in particular,  FIGS. 6 and 7 . The mounting adapter  14  has two holes—in each case, one for one of the plug contacts  21 A,  21 B. In the assembled state of the module  1 , the mounting adapter  14  is mounted on the opening  101  of the sleeve  10 —optionally, with a fluid-tight connection—e.g., plugged thereon. The module  1  can be self-contained and also sealed. 
       FIG. 14  shows the module  1  with the load lines  30  connected thereto, wherein it is also already mounted on a part of the plug-in connector part  2 —in the present case, on a connector face part  24  of the plug-in connector part  2 , which forms the plug sections  22 ,  23 . For this purpose, the module  1  with the mounting adapter  14  is connected to the part of the plug-in connector part  2  (i.e., here, the connector face part  24 ). In the example shown, the part and the mounting adapter  14  have compatible conical sections which facilitate an exact adjustment. Consequently, in production, the plug contacts  21 A,  21 B are then each screwed to the corresponding busbar  11 A,  11 B; see, in particular, the enlarged view in  FIG. 15 . This facilitates simple production. In addition, the typically mechanically highly-stressed plug contacts  21 A,  21 B can be easily replaced. The mounting adapter  14  is thus formed to fit to a part of the plug-in connector part  2 . The mounting adapter  14  thus serves as an interface for mounting the pre-assembled module  1  on the plug-in connector part  2 . 
       FIG. 16  shows how the mounting adapter  14  is fastened to the sleeve  10 —specifically, to the opening  101  of the sleeve  10 , and, in fact, by means of a latching connection. The mounting adapter  14  has a circumferential projection which engages in a circumferential groove of the sleeve  10 . 
       FIG. 17  shows the feedthrough section  102  of the sleeve  10  with the load lines  30  fed through. The feedthrough section  102  is designed in the form of a grommet (e.g., a rubber grommet) and adjoins the load lines  30  in sections. 
     While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. It will be understood that changes and modifications may be made by those of ordinary skill within the scope of the following claims. In particular, the present invention covers further embodiments with any combination of features from different embodiments described above and below. Additionally, statements made herein characterizing the invention refer to an embodiment of the invention and not necessarily all embodiments. 
     The terms used in the claims should be construed to have the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article “a” or “the” in introducing an element should not be interpreted as being exclusive of a plurality of elements. Likewise, the recitation of “or” should be interpreted as being inclusive, such that the recitation of “A or B” is not exclusive of “A and B,” unless it is clear from the context or the foregoing description that only one of A and B is intended. Further, the recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise. Moreover, the recitation of “A, B and/or C” or “at least one of A, B or C” should be interpreted as including any singular entity from the listed elements, e.g., A, any subset from the listed elements, e.g., A and B, or the entire list of elements A, B and C. 
     LIST OF REFERENCE SIGNS 
     
         
           1  Module 
           10  Sleeve 
           100  Interior space 
           101  Opening 
           102  Feedthrough section 
           11 A,  11 B Busbar 
           110  First section 
           111  Second section 
           112  Mounting section 
           113  Receptacle 
           12 A- 12 D Heat capacity element 
           13  Insulating support 
           130  Separating section 
           131 ,  132  Transverse part 
           133  Screw dome 
           14  Mounting adapter 
           15 A,  15 B Housing part 
           16  Screw 
           17  First section 
           18  Second section 
           2  Plug-in connector part 
           20  Housing 
           200 ,  201  Housing part 
           202  Handle 
           21 A,  21 B Plug contact 
           22 ,  23  Plug-in section 
           24  Plug-in face part 
           3  Cable 
           30  Load line 
           4  Mating connector part 
           40  Counter-contact element 
           5  Vehicle 
           6  Charging station 
         E Insertion direction