Plug connector part for mechanical and electrical connection to a mating plug connector part

Abstract

The invention relates to a plug connector part for mechanical and electrical connection to a mating plug connector part, in particular a motor vehicle-side charging socket (1) for coupling to a charging plug as components of an electrical charging infrastructure for electric or hybrid motor vehicles, or vice versa. To this end, a housing (2, 3) and at least one electrical contact element (4) located in the housing (2, 3) are provided. Moreover, a passively cooled heat conductor (7) is provided, one end (7a) of which is connected to the contact element (4) and the other end (7b) of which has a heat sink (8). According to the invention, the heat conductor (7) extends through a housing opening (2a, 3a) and is equipped outside the housing (2, 3) with the heat sink (8) arranged there.

Description

[0001] Description

[0002] Connector part for mechanical and electrical connection with a mating connector part

[0003] The invention relates to a plug connector part for mechanically and electrically connecting to a mating plug connector part, in particular a motor vehicle-side charging socket for coupling to a charging plug as components of an electrical charging infrastructure for electric or hybrid motor vehicles, or vice versa, with a housing made of plastic and at least one electrical contact element arranged in the housing, and with a preferably passively cooled heat line which is connected at one end to the contact element and has a heat sink at its other end.

[0004] The connector part is generally a charging socket in a motor vehicle that can be coupled to an associated charging plug, for example, found at an electric charging station. During the coupling process, an electrical and mechanical connection is established between the charging socket and the charging plug. The charging plug, like the charging socket, is part of the electrical charging infrastructure used to charge the rechargeable energy storage devices or accumulators of electric or hybrid vehicles. In principle, the connector part on the motor vehicle can also be a charging plug instead of a charging socket. In this case, the charging station is equipped with an associated charging socket.Typically, however, electric or hybrid vehicles have a charging socket with several electrical contact elements arranged in the housing, into which the charging plug connected to the charging station is inserted to electrically charge the vehicle in question. In order to be able to supply the high electrical power of the electric motors in the vehicle in question with the necessary electrical energy and to provide a sufficient range, high-voltage batteries or accumulators are used today, which are typically charged with high-voltage direct current. In addition to such DC charging processes (direct current), most electric or hybrid vehicles also allow for charging via alternating current, i.e., AC charging.However, this point is usually operated with low currents and long charging times, whereas the previously described DC charging process involves high voltages and high currents, resulting in short charging times. Especially with DC charging processes, the fundamental problem is that the electrical contact elements used at this point become increasingly hot due to the high current of up to several tens of amps or more. This increases their resistance, which hinders the electrical charging process and the desired rapid charging.

[0005] For this reason, the prior art according to EP 3 446 372 B1 already uses a heat pipe whose first end is connected to a metallic connector. Furthermore, a heat sink is provided, which serves to dissipate heat from the at least one contact element.

[0006] However, the previously known teaching is aimed at the design of a charging plug and not a charging socket. In any case, the heat loss at the electrical contact element can only be inadequately dissipated via the heat sink arranged in the housing via heat conduction to the heat sink. This can be attributed, among other things, to the fact that the housing of the charging plug is completely closed because such charging plugs, as components of the charging infrastructure, are installed in the vicinity of electric charging stations, which in turn are generally exposed to the elements and, in particular, rain. While there are already approaches in the further prior art according to DE 20 2019 102 461 U1 or DE 10 2015 013 296 A1 to intensify cooling with a fan, this does not change the fundamental problem of heat dissipation from the housing.

[0007] The previously known teachings according to EP 4 000 989 A1 and EP 4 000 992 A1 face similar problems. In this case, too, the heat sink is located inside the housing, whereby, due to the housing, heat buildup may even be observed at this location depending on the heat loss.

[0008] The invention is based on the technical problem of further developing such a connector part in such a way that overall heat dissipation is improved compared to the prior art.

[0009] To solve this technical problem, the invention proposes, in a generic connector part for mechanical and electrical connection with a mating connector part, that the heat conduction passes through a housing opening and is equipped outside the housing, i.e. in an outer area, with at least one heat sink arranged there.

[0010] The invention therefore initially relies on at least one, in particular passively cooled, heat pipe or a "heat pipe" inserted at this point. This heat pipe, in the form of a preferably metallic tube, is then thermally connected at one end to the electrical contact element. The heat sink is provided at the other end, so that a thermally conductive connection is available from the electrical contact element via the heat pipe to the heat sink. For this purpose, the heat sink is also thermally connected to the heat pipe or the metallic tube provided at this point. Advantageously, the at least one heat sink comprises a metal with good thermal conductivity, in particular aluminum and / or copper, or a ceramic material, in particular aluminum oxide and / or aluminum nitride. Particularly advantageously, the heat sink comprises a plurality of fins, in particular made of copper or aluminum.

[0011] Of particular inventive importance is the further circumstance that the at least one heat conductor passes through a housing opening, i.e., is led outside the housing. The heat sink arranged or attached there is then located in this outer region. This allows heat generated on or in the electrical contact element to be dissipated particularly effectively via heat conduction to the heat sink, which, in turn, is arranged outside the housing and can therefore dissipate the resulting heat particularly effectively via convection.

[0012] The invention is based on the realization that such connector parts in the form of a charging socket are typically installed in the area of ​​a body opening on or in a motor vehicle. The body opening is located, for example, in a front or rear fender, above or even in a wheel arch. This location generally not only provides sufficient installation space for the connector part or charging socket, but also ensures that the heat sink located outside the housing can easily communicate with, for example, the ambient air. At the same time, the heat sink is also protected from rain or stone chips because it is usually located in the wheel arch behind a wheel cover.In any case, this provides particularly intensive heat dissipation, and phenomena such as heat buildup due to a closed housing, as in the prior art, can be avoided from the outset and by design. This is where the main advantages lie. It is also conceivable that a plurality (i.e., more than one) of heat conductors, preferably between two and five, connect the contact element to the heat sink, at least in a thermally conductive manner.

[0013] Within the scope of a further advantageous embodiment, the at least one heat pipe has electrical insulation at least in the outer region and relative to the heat sink provided there. The electrical insulation usually extends through the housing opening into the interior of the housing. The invention is based on the recognition that the heat pipe, as already explained, is preferably a metallic tube. The metallic tube can, for example, also enclose a hermetically sealed volume. This volume, in turn, is filled with a working fluid for heat transport, for example, water.

[0014] In this way, the heat pipe or the metal tube operates according to the so-called wick principle. This means that the working fluid contained within the volume is evaporated in the area of ​​the electrical contact element, for example, and condensed in the area of ​​the heat sink. The wick principle is based on the condensed working fluid being returned to the evaporator.

[0015] In any case, heat is transported overall from the electrical contact element as the heat source via the at least one, preferably passively cooled heat pipe to the heat sink as the heat sink. Since the electrical contact element and the heat sink are preferably metallic and the heat pipe is advantageously the metallic pipe described above, electrical insulation of the heat sink and the area of ​​the heat pipe in the outer region, i.e. outside the housing, is required. This is ensured by the electrical insulation in the outer region and from the heat sink provided there. This means that the heat sink is electrically insulated from the heat pipe by means of the insulation. For this purpose, the electrical insulation extends through the housing opening into the interior of the housing, so that neither the heat sink nor the heat pipe in the outer region carry any voltage or current.Electrical insulation can be a plastic coating on the metal pipe in the desired area. However, it can also be implemented as shrink tubing or other plastic sheathing for the metal pipe.

[0016] The electrical insulation in the area of ​​the housing opening may also serve as a seal for the housing opening. However, an additional seal can also be provided in the area of ​​the housing opening.

[0017] In order to further intensify the cooling effect and thus the heat transport from the electrical contact element via the heat conduction to the heat sink, the heat sink can be equipped with at least one additional coolant. This then provides active cooling of the heat conduction. The coolant is usually at least one electrically driven fan. This can further increase the cooling effect of the heat sink through convection. The at least one fan can be controlled by a control unit for this purpose, at least during the electrical charging process. In principle, the coolant, in particular the fan, can also be operated for a certain period of time after the charging process has ended in order to cool the heat sink if necessary. A fan according to the invention can preferably be designed as an axial or radial fan.Furthermore, it is conceivable that two or more fans are provided. It is also conceivable that fans of different dimensions or designs (axial or radial fans) are provided. Particularly when the heat sink has a plurality or multiplicity of fins, it is particularly preferred that the at least one fan is arranged on the heat sink in such a way that the generated air flow flows around the fins, thus further increasing the cooling performance. Furthermore, it is conceivable that the fan is integrated into the heat sink, at least in sections.

[0018] Particularly preferably, the fan and / or the control unit can be connected to at least one sensor for monitoring the temperature and / or the fan speed and / or the airflow of the fan. The control unit is particularly designed such that the fan can be controlled and / or regulated depending on the temperature. Furthermore, the fan speed can be adjusted accordingly. This can, in particular, improve acoustic comfort.

[0019] Furthermore, it is conceivable for the fan to have at least one damping means for vibration reduction. In particular, the fan can be attached to the heat sink, for example, with decoupler pins. This prevents direct contact of the fan or fan housing with the heat sink, which is particularly metallic. Alternatively or additionally, a support frame can be provided for the fan, which is arranged between the fan and the heat sink and also prevents direct contact between the fan and the heat sink. The support frame or the decoupler pins are preferably made of rubber or at least comprise rubber.

[0020] As already described in the introduction, the preferably passively cooled heat pipe is connected to the contact element at one end. This is usually done by inserting the heat pipe into the contact element at that end. In this case, a specific design has proven advantageous in which the heat pipe runs predominantly perpendicular to the longitudinal extension of the contact element.

[0021] This means that the heat pipe, or the metal tube provided at this point, generally extends perpendicular to the longitudinal extension of the contact element and consequently also to the mating connector part, which electrically and mechanically connects the mating connector part to the connector part. This allows the heat sink provided outside the housing of the connector part to be easily positioned above or below the housing and communicate with the ambient air there during the electrical charging process of the vehicle, as already described in the introduction.

[0022] In this context, it is advantageous to proceed in such a way that the heat pipe extends in an arc-shaped manner into a top opening of a connecting piece of the contact element. This means that the heat pipe is arranged predominantly perpendicular to the longitudinal extension of the contact element, requiring a curved route for the heat-conducting connection to the electrical contact element, namely such that the heat pipe extends in an arc-shaped manner into the top opening of the connecting piece.

[0023] In principle, however, the heat pipe can also be immersed straight or predominantly straight into the top opening in question of the connecting piece and in this way establish the desired heat-conducting connection with the connecting piece and thus the contact element.

[0024] In both cases, the connector is electrically and thermally connected to the contact element. For this purpose, the connector can be connected to the contact element, for example, by a plug connection or in some other way. A one-piece design of the connector and contact element is also possible.

[0025] The top opening in the connection piece is typically a half-cylinder opening if the heat conduction runs in a curve in this area. This is because the connection piece, like the contact element, is generally cylindrical. In the event that the heat conduction is connected to the connection piece in a predominantly straight line, the top opening in the connection piece is typically designed as a cylindrical bore. In either case, the heat conduction is initially received in a hollow bore in the connection piece of the contact element and held there. It then leaves the connection piece in question via the curve or predominantly straight via the top opening of the connection piece, in order to then transition to a predominantly vertical course compared to the longitudinal extension of the contact element or to maintain this vertical course.This provides and achieves particularly favorable heat conduction because the heat pipe is immersed with one end into the corresponding hollow bore in the connecting piece and the connecting piece with the hollow bore encloses the said end of the heat pipe.

[0026] This creates intimate thermal contact between the connector and the heat pipe. Furthermore, since the connector is electrically and thermally connected to the contact element, any heat loss generated at the contact element is transferred particularly effectively to the heat pipe, which in turn transports the resulting heat to the heat sink.

[0027] Since the aforementioned electrical insulation is usually provided at this point between the other end of the heat pipe and the heat sink, it is important to use electrical insulation that is electrically insulating but also thermally conductive. Thermoplastics that are designed as plastic injection molded parts or are suitable for overmolding the metal pipe in the relevant area have proven to be advantageous here. Such thermoplastics such as PP (polypropylene), PA (polyamide), PBT (polybutylene terephthalate), PE (polyethylene), etc. typically have thermal conductivities that are, for example, 0.23 W / (m x K) for polypropylene (PP) or up to 0.35 W / m x K for polyamides. Values ​​of approximately 0.5 W / (m x K) have been observed with polyethylene (PE).To increase thermal conductivity while still maintaining electrical insulation, the aforementioned plastics can also be incorporated with embedded fillers. Fillers that are both electrically insulating and thermally conductive have proven particularly advantageous in this context. Examples include aluminum compounds or drilled compounds, particularly preferably aluminum oxide or boron nitride. This can increase the thermal conductivity of the plastic in question by at least a factor of three.

[0028] The result is a connector component for mechanical and electrical connection to a mating connector component that offers significantly improved heat transfer compared to the prior art. This is primarily due to the heat sink being routed to the outside of a housing, preferably made of plastic, along the heat conduction line, allowing particularly effective convection with ambient air, for example. These are the key advantages.

[0029] The invention will now be explained in more detail with reference to a drawing which merely represents an exemplary embodiment; in which:

[0030] Fig. 1 the connector part according to the invention in a perspective rear view,

[0031] Fig. 2 shows the connector part according to Fig. 1 partially broken open in a perspective side view.

[0032] Fig. 3 shows a modified embodiment comparable to Fig. 2. The figures show a plug connector part for mechanically and electrically connecting to a mating plug connector part. In fact, the plug connector part in the exemplary embodiment according to Figs. 1 and 2 is a motor vehicle-side charging socket 1. The charging socket 1 is designed to be coupled to a charging plug, which is not shown in detail. The charging plug and the charging socket 1 each represent a component of an electrical charging infrastructure for electric or hybrid motor vehicles. For this purpose, the charging plug (not shown) is plugged into the charging socket 1 in the direction of the arrow S indicated in Fig. 2, which represents the plugging direction S that is relevant at this point for joining the charging socket 1 and the charging plug.

[0033] The charging socket 1 is equipped with a housing 2, 3, which is composed of a front cover 2 and a rear cover or rear cover 3 that can be connected to it, which can be seen particularly in the rear view according to Fig. 1. Several electrical contact elements 4 are then arranged and provided in the housing 2, 3, which are contact elements 4 for a DC charging process. For this purpose, the electrical contact elements 4 are each electrically and thermally coupled to a connection piece 5, which can be understood in particular from the illustration in Fig. 2. The respective electrical contact elements 4 and the connection piece 5 can in principle also be formed as a single piece, but in any case, according to the exemplary embodiment - as described - they are electrically and thermally coupled to one another.

[0034] In addition to the electrical contact elements 4 for the previously mentioned DC charging process, further contact elements 6 are also implemented, which are required for an AC charging process, but are not relevant for the subsequent considerations. Rather, the electrical contact elements 4 are considered for the DC charging process because this is associated with a high electrical current. Additionally and essential, a passively cooled heat pipe 7 is also implemented, which, according to the exemplary embodiment, is a "heat pipe" or a metallic tube as described above, which preferably has the hermetically coupled volume described above inside and a working medium for heat transport therein. For this purpose, the metallic tube or heat pipe 7 has a defined length and is closed at both ends.For heat transport, the respective heat pipe 7 is thermally coupled at one end 7a to the contact element 4 or the connecting piece 5. The other end 7b of the passively cooled heat pipe 7 is thermally coupled to a heat sink 8, as can best be seen in Fig. 2. According to the exemplary embodiment, two electrical contact elements 4 are implemented (DC charging process), each of which is thermally coupled to a common heat sink 8 via associated and likewise two heat pipes 7. This provides a thermally conductive connection from the respective electrical contact element 4 or the associated connecting piece 5 via the passively cooled heat pipe 7 to the heat sink 8.

[0035] Of particular importance is the fact that, according to the invention, the heat pipe 7 passes through a housing opening 2a, 3a. In fact, the housing opening 2a in question is located on the one hand in the front housing or the front cover 2 and, on the other hand, as a further housing opening 3a in the rear housing or the rear cover 3, as can be seen from a comparison of Fig. 1 and 2. This is of course only an example and is in no way restrictive. In any case, the design is such that the heat pipe 7 passes through the relevant housing opening 2a, 3a and as a result the heat sink 8 can be arranged in the outer region, i.e., is arranged outside the housing 2, 3. In this outer region of the housing 2, 3, the heat sink 8 can dissipate heat to the ambient air particularly effectively by convection, as already described in the introduction.Since the heat pipe 7 in the exemplary embodiment is designed as a metallic pipe and is thermally conductive and thus also electrically connected to the contact element 4 or the connecting piece 5 electrically connected thereto, an additional electrical insulation 9 is provided, at least in the outer region and opposite the heat sink 8 provided there. According to the exemplary embodiment, the electrical insulation 9 is a plastic sheathing of the heat pipe 7 or the metallic pipe, which can be applied to the pipe in question in connection with a plastic injection molding process. In any case, the electrical insulation 9 is found in the outer region and opposite the heat sink 8 provided there and extends through the housing opening 2a, 3a into the interior of the housing 2, 3. This can be seen in particular from Fig.2, which shows that the electrical insulation 9 extends several millimeters up to 1 cm or even more into the interior of the housing 2, 3 through the respective opening 2a, 3a. In this way, the plastic electrical insulation 9 simultaneously functions as a seal for the housing opening 2a, 3a, so that the housing 2, 3 is splash-proof.

[0036] The electrical insulation 9 is made of a plastic, which was already referred to and described in the introduction, and is therefore both electrically insulating and thermally conductive. For this purpose, the plastic in question can be equipped with appropriate fillers, also described in the introduction. In any case, the electrical insulation 9 as a whole ensures that the relevant heat conductor 7 in the outer region of the housing 2, 3 does not carry any voltage and that no current can flow through it, while at the same time ensuring the required heat conduction from the electrical contact element 4 via the heat conductor 7 to the heat sink 8.

[0037] It can be seen that the heat pipe 7 is inserted with its one end 7a into the contact element 4 or the associated connecting piece 5, specifically into a corresponding hollow bore in the connecting piece 5 adapted to the heat pipe 7. In the interior of the housing 2, 3, the heat pipe 7 runs predominantly perpendicular to the longitudinal extent of the contact element 4 and thus also of the connecting piece 5. Consequently, the heat pipe 7 in question also has a predominantly vertical arrangement compared to the previously described plug-in direction S.

[0038] As a result, in the embodiment shown in Fig. 2, the heat conductor 7 is guided in an arcuate manner into a top opening 5a of the connecting piece 5 of the contact element 4 and is immersed in this top opening 5a. Since, in the embodiment shown in Fig. 2, both the connecting piece 5 and the contact element 4 are cylindrical, the top opening 5a in the variant shown in Fig. 2 is designed as a half-cylindrical opening. This is, of course, only an example and is in no way restrictive.

[0039] In the variant shown in Fig. 3, the procedure is such that the heat pipe 7 predominantly extends straight into the top opening 5a of the connecting piece 5 of the contact element 4, which is also implemented in this case. The top opening 5a in question is designed as a cylindrical bore or hollow cylindrical bore in this case, because the heat pipe 7 is tubular or cylindrical in the exemplary embodiment. In both cases, the heat pipe 7 is thermally coupled to the connecting piece 5 and thus to the contact element 4.

[0040] To increase heat dissipation from the heat sink 8, the latter is equipped with an additional coolant 10 according to the exemplary embodiment. The coolant 10 is, for example, a fan 10. The fan 10 may be electrically controlled by a control unit, at least for the period while an electrical charging process is taking place via the two electrical contact elements 4. In principle, the control unit can operate the coolant or the fan 10 for a specific and adjustable period of time even after the charging process in order to prevent any overheating of the heat sink 8 from the outset. For this purpose, the fan 10 or the coolant 10 is located on the head of the heat sink 8, so that the air sucked in by the fan 10 flows through individual fins provided inside the heat sink 8 in the longitudinal direction thereof.

[0041] List of reference symbols

[0042] Charging socket 1

[0043] Front cover 2

[0044] Housing opening 2a, 3a

[0045] Housing 2, 3

[0046] Front cover 2

[0047] Back cover 3

[0048] Contact elements 4

[0049] Connector 5

[0050] Opening 5a

[0051] Contact elements 6

[0052] Heat conduction 7

[0053] End of 7a

[0054] End 7b

[0055] Heatsink 8

[0056] Insulation 9

[0057] Coolant 10

[0058] Fan 10

[0059] Arrow S

[0060] Plug direction S

Claims

Patent claims 1. Plug-in connector part for mechanically and electrically connecting to a mating plug-in connector part, in particular a motor vehicle-side charging socket (1) for coupling to a charging plug as components of an electrical charging infrastructure for electric or hybrid vehicles, with a housing (2, 3) and at least one electrical contact element (4) arranged in the housing (2, 3), and with at least one preferably passively cooled heat pipe (7), which is connected at one end (7a) to the contact element (4) and has a heat sink (8) at its other end (7b), characterized in that the at least one heat pipe (7) passes through a housing opening (2a, 3a) and is equipped with the heat sink (8) arranged there outside the housing (2, 3).

2. Connector part according to claim 1, characterized in that the heat line (7) has an electrical insulation (9), in particular outside the housing (2, 3) and opposite the heat sink (8) provided there.

3. Connector part according to claim 2, characterized in that the electrical insulation (9) extends through the housing opening (2a, 3a) into the interior of the housing (2, 3).

4. Connector part according to one of claims 1 to 3, characterized in that the heat sink (8) is equipped with an additional coolant (10).

5. Connector part according to claim 4, characterized in that the Coolant (10) is designed as, for example, an electrically driven fan (10).

6. Connector part according to one of claims 1 to 5, characterized in that the heat pipe (7) is designed as a metallic tube, in particular that the tube encloses a hermetically sealed volume.

7. Connector part according to claim 6, characterized in that the volume is filled with a working medium for heat transport, for example water or ammonia.

8. Connector part according to one of claims 1 to 7, characterized in that the heat line (7) is inserted with its one end (7a) into the contact element (4) or a connecting piece (5) electrically connected thereto.

9. Connector part according to one of claims 1 to 8, characterized in that the heat conduction (7) runs predominantly perpendicular to the longitudinal extent of the contact element (4).

10. Connector part according to one of claims 1 to 9, characterized in that the heat line (7) dips in an arcuate or predominantly straight manner into an upper opening (5a) of the connecting piece (5) of the contact element (4).

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