Plug for mechanical and electrical connection to mating plug

Abstract

The invention relates to a plug for mechanical and electrical connection to a mating plug, in particular for a motor vehicle-side charging socket (1) coupled to a charging plug as a component of a charging infrastructure of an electric or hybrid vehicle, and vice versa. For this purpose, a housing (2, 3) and at least one electrical contact element (4) arranged in the housing (2, 3) are provided. Furthermore, a passively cooled heat line (7) is provided, which is connected with one end (7a) thereof to the contact element (4) and has a cooling body (8) at the other end (7b) thereof. According to the invention, the heat line (7) passes through the housing opening (2a, 3a) and is equipped outside the housing (2, 3) with a cooling body (8) arranged there.

Description

Technical Field

[0001] The invention relates to a plug connector for mechanically and electrically connecting to a mating plug connector, in particular for a motor vehicle-side charging socket connected to a charging plug as a component of a charging infrastructure for an electric vehicle or a hybrid vehicle, and vice versa, the plug connector comprising: a housing made of plastic; at least one electrical contact element arranged in the housing; and a preferably passively cooled heat pipe, which is connected to the contact element with one end thereof and has a cooling body at its other end. Background Art

[0002] The plug connector is usually a charging socket in a motor vehicle, which can be connected to an associated charging plug, which is arranged on a charging post, for example. As a result, an electrical and at the same time mechanical connection between the charging socket and the charging plug is achieved and caused during the connection process. Here, the charging plug and the charging socket belong to the charging infrastructure, with the help of which the rechargeable energy storage device or battery of the electric vehicle or hybrid vehicle can be charged. In principle, the plug connector on the motor vehicle can also be a charging plug in addition to the charging socket. In this case, the charging post is equipped with an associated charging socket. However, in general, the electric vehicle or hybrid vehicle has a charging socket with a plurality of electrical contact elements arranged in a housing, and the charging plug connected to the charging post is inserted into the charging socket for charging the relevant motor vehicle.

[0003] In order to supply the required electrical energy to the high electrical power of the motor provided in the relevant motor vehicle and to provide sufficient driving range on the other hand, high-voltage batteries or high-voltage accumulators are now typically charged with a high-voltage direct current voltage. In addition to this DC charging process (direct current), most electric vehicles or hybrid vehicles can also realize the charging process by alternating voltage, that is, AC charging process (alternating current). However, in most cases, low current and long charging time are used here, while high voltage, high current and the resulting short charging time are realized in the DC charging process described above. In particular, in the DC charging process, due to the high current intensity of up to tens of amperes or more, there is the following main problem, that is, the electrical contact elements used here gradually heat up. As a result, their resistance is increased, which hinders the charging process and the desired rapid charging.

[0004] For this reason, the prior art according to EP 3 446 372 B1 already works with a heat pipe which is connected with its first end to a metal connection piece. In addition, a cooling body is provided for conducting heat away from at least one contact element.

[0005] However, the previously known teachings are directed to the design of the charging plug, not to the charging socket. In any case, the heat loss generated at the electrical contact elements can only be dissipated inadequately via the heat line to the cooling body arranged in the housing. This can also be attributed to the completely closed design of the housing of the charging plug, since such charging plugs are installed as part of the charging infrastructure in the area of ​​the charging post, which is usually not protected from the weather, in particular rain.

[0006] Although in other prior art according to DE 20 2019 102 461 U1 or corresponding to DE 10 2015 013 296 A1, a solution of using a fan to enhance cooling has been provided. However, this does not change the main 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 also face similar problems, since in this case the cooling body is also arranged inside the housing, where heat accumulation can even occur due to the heat losses generated by the housing. Summary of the invention

[0008] The technical problem to be solved by the present invention is to improve such a plug connector in such a way that the heat dissipation is improved overall compared to the prior art.

[0009] In order to solve this technical problem, the present invention proposes, with respect to such a plug connector for mechanical and electrical connection to a mating plug connector, that a heat line passes through a housing opening and is provided outside the housing, ie in an outer region, with at least one heat sink arranged therein.

[0010] The invention therefore relates firstly to at least one heat pipe, in particular passively cooled, or a "heat pipe" as used herein. This heat pipe, preferably in the form of a metal pipe, is now connected with one end thereof to an electrical contact element in a thermally conductive manner. A cooling body is provided at the other end, so that a thermally conductive connection is provided as a whole from the electrical contact element via the heat pipe to the cooling body. For this purpose, the cooling body is also connected in a thermally conductive manner to the heat pipe or the metal pipe provided there.

[0011] Advantageously, at least one heat sink comprises a metal that can conduct heat well, 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 lamellae, in particular lamellae made of copper or aluminum.

[0012] It is also particularly important for the invention that at least one heat line is led through the housing opening, i.e. to the outside of the housing. A cooling body is therefore provided in this outer region and is arranged or mounted there. As a result, the heat generated at or in the electrical contact element can be particularly effectively conducted via the heat line to the cooling body, which is itself arranged outside the housing and can therefore particularly effectively discharge the generated heat by convection.

[0013] The invention is based on the knowledge that such plug-in connectors in the form of charging sockets are typically installed in the region of a body opening on or in a motor vehicle. The body opening is, for example, located in the front or rear fender, i.e., above the wheel housing or even in the wheel housing. In this case, not only is sufficient installation space generally available for the plug-in connector or the charging socket, but it is also ensured that the cooling body arranged outside the housing can be easily connected, for example, to the ambient air. At the same time, however, the cooling body is also protected from rain or gravel, since the cooling body is usually located in the wheel housing behind the fender. In any case, this provides particularly strong heat dissipation and, for example, possible heat accumulation due to a closed housing as in the prior art can be avoided from the outset for structural reasons. This is a major advantage of the invention.

[0014] Furthermore, it is conceivable that a plurality (ie more than one) of heat pipes, preferably 2 to 5 heat pipes, connect the contact element to the heat sink in at least a thermally conductive manner.

[0015] In another advantageous embodiment, at least one heat pipe has an electrical insulation, at least in the outer region and relative to the cooling body arranged there. In most cases, the electrical insulation passes through the housing opening into the interior of the housing. The invention is based on the knowledge that the heat pipe, as already described, is preferably a metal pipe. In this case, the metal pipe can also enclose a sealed volume, for example. This volume itself is filled with a working medium, for example water, for heat transfer.

[0016] In this way, the heat pipe or metal tube works according to the so-called wick principle. That is, the working medium arranged inside the volume is evaporated in the area of ​​the electrical contact element, for example, and liquefied in the area of ​​the cooling body. The wick principle is now based on the fact that the liquefied working medium is guided back to the evaporator.

[0017] In any case, heat transfer from the electrical contact element as a heat source to the cooling body as a radiator via at least one heat pipe (heat pipe) preferably passively cooled is achieved as a whole. Because the electrical contact element and the cooling body are preferably metallically constructed and the heat pipe is advantageously the metal pipe already described, it is necessary to electrically insulate the cooling body and the heat pipe in the external area, that is, in the area outside the housing. For this purpose, an electrical insulation portion is provided in the external area and relative to the cooling body arranged there. In other words, the cooling body is electrically insulated relative to the heat pipe by means of an insulation portion. For this purpose, the electrical insulation portion enters the interior of the housing through the housing opening, so that the cooling body and the heat pipe do not conduct voltage or conduct electricity in the external area. The electrical insulation portion can be a plastic coating of the metal pipe in the desired area. However, in principle, the electrical insulation portion can also be designed as a heat shrinkable sleeve or other sheath made of plastic for the metal pipe.

[0018] In this case, the electrical insulation in the region of the housing opening can simultaneously serve as a seal for the housing opening. In principle, however, an additional seal can also be provided in the region of the housing opening.

[0019] In order to further enhance the cooling effect and thus further enhance the heat transfer from the electrical contact element via the heat pipe to the heat sink, the heat sink can be equipped with at least one additional cooling device. Therefore, the heat pipe is actively cooled to a certain extent. The cooling device is in most cases at least one electrically driven fan. The cooling effect of the heat sink can thus be additionally increased by convection. For this purpose, at least one fan can be controlled by a control unit, that is, at least during the charging process. However, in principle, the cooling device, in particular the fan, can also be operated for a period of time after the charging process is completed so as to cool the heat sink if necessary. The fan according to the present invention can preferably be designed as an axial fan or a radial fan. In addition, it is conceivable that two or more fans are provided. It is also conceivable that fans of different sizes or structural types (axial fans or radial fans) are provided. In particular, when the heat sink has multiple or a large number of fins, it is particularly preferred that at least one fan is arranged on the heat sink in the following manner, that is, the fins are circulated by the generated air flow, thereby further improving the cooling performance. In addition, it is conceivable that the fan is at least partially integrated in the heat sink.

[0020] Particularly preferably, the fan and / or the control unit can be connected to at least one sensor for monitoring the temperature of the fan and / or the fan speed and / or the air flow. In this case, the control unit is particularly designed to control and / or regulate the fan in a temperature-dependent manner. In addition, the fan speed can be adjusted accordingly. This can improve the acoustic comfort in particular.

[0021] It is also conceivable that the fan has at least one vibration damping element for reducing vibrations. In particular, the fan can be fixed to the cooling body, for example, by means of a decoupling pin. This avoids direct contact between the fan or the fan housing and the cooling body, which is in particular metal. Alternatively or additionally, a base frame for the fan can be provided, which is arranged between the fan and the cooling body and also avoids direct contact between the fan and the cooling body. The base frame or the decoupling pin is preferably formed from rubber or at least has rubber.

[0022] As already described at the outset, the heat pipe, which is preferably passively cooled, is connected with one of its ends to the contact element. For this purpose, in most cases the heat pipe is inserted with the relevant end into the contact element. Specifically, the following embodiment has proven to be advantageous in which the heat pipe is substantially perpendicular to the longitudinal extension direction of the contact element.

[0023] That is, the heat pipe or the metal pipe arranged there is usually perpendicular to the longitudinal extension direction of the contact element and therefore also perpendicular to the plug-in direction of the mating connector, in which the mating connector is electrically and mechanically connected to the connector. As a result, the heat sink arranged outside the housing of the connector can be easily placed on or below the housing to a certain extent and there communicate with the ambient air during the charging process of the motor vehicle, as already described at the beginning.

[0024] In this respect, it is advantageous to provide that the heat pipe is embedded in an arcuate manner in the upper opening of the connection piece of the contact element. That is, the arrangement of the heat pipe essentially perpendicular to the longitudinal extension of the contact element requires an arcuate guidance of the heat pipe for the heat-conducting connection with the electrical contact element, i.e., the heat pipe is embedded in an arcuate manner in the upper opening of the connection piece.

[0025] In principle, however, the heat pipe can also be inserted linearly or substantially linearly into the relevant upper opening of the connecting piece and in this way achieve the desired heat-conducting connection to the connecting piece and therefore to the contact element.

[0026] In both cases, the connector is itself electrically and thermally connected to the contact element. For this purpose, the connector can be connected to the contact element, for example, by plugging or in other ways. An integral design of the connector on the one hand and the contact element on the other hand can also be achieved.

[0027] The upper opening in the connection piece is typically a semi-cylindrical opening in the case where the heat pipe extends in an arc in this area. Therefore, the connection piece and the contact element are usually cylindrical. If the heat pipe is connected to the connection piece in an essentially straight line, the upper opening in the connection piece is typically designed as a cylindrical hole.

[0028] In either case, the heat pipe is first received in a hollow bore in a connector of the contact element and held therein and then leaves the connector in question in an arc or substantially straight line via the upper opening of the connector so that it can then transition to a substantially perpendicular course relative to the longitudinal extension of the contact element or maintain this perpendicular course. This provides and enables particularly advantageous heat conduction, since the heat pipe is embedded with one end in the associated hollow bore in the connector and the connector surrounds the end of the heat pipe with the hollow bore.

[0029] In this case, a close thermal contact is formed between the connector and the heat pipe. In addition, since the connector is electrically and thermally connected to the contact element, any heat loss that may occur on the contact element is transferred particularly effectively to the heat pipe, which then transfers the heat that is formed to the cooling body.

[0030] Since the already mentioned electrical insulation is usually provided between the other end of the heat pipe and the heat sink, it is important to use an insulation which is electrically insulating but at the same time thermally conductive as the electrical insulation. Thermoplastics have proven to be advantageous here, which are designed as plastic injection-molded parts or are suitable for extrusion coating of metal pipes in the relevant areas. Such thermoplastics, such as PP (polypropylene), PA (polyamide), PBT (polybutylene terephthalate), PE (polyethylene), etc., typically have a thermal conductivity of, for example, 0.23 W / (m×K) for polypropylene (PP) or up to 0.35 W / (m×K) for polyamide. For polyethylene (PE), the value is approximately 0.5 W / (m×K).

[0031] In order to increase the thermal conductivity while still providing electrical insulation, the plastics mentioned above can also be provided with an inserted filler. In this respect, fillers have proven to be particularly advantageous, which are designed to be electrically insulating and at the same time thermally conductive. These include, by way of example, aluminum compounds or boron compounds, particularly preferably aluminum oxide or boron nitride. As a result, the thermal conductivity of the relevant plastic can be increased by at least a factor of three.

[0032] Thus, a plug connector for mechanical and electrical connection to a mating plug connector is provided and realized, which has a significantly improved heat transfer compared to the prior art. This can be mainly attributed to the fact that the cooling body is already arranged in a heat line outside the housing, which is preferably made of plastic, so that particularly effective convection with the ambient air is achieved here, for example. This is a major advantage of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The invention is described in detail below with reference to the accompanying drawings which show only one embodiment; in the drawings:

[0034] Figure 1The plug connector according to the invention is shown in a perspective rear view,

[0035] FIG. 2 shows a perspective side view of a partially opened Figure 1 The connector,

[0036] FIG. 3 shows a modified embodiment similar to FIG. 2 . DETAILED DESCRIPTION

[0037] The accompanying drawings show a plug connector for mechanically and electrically connecting to a mating plug connector. Figure 1 2 is a motor vehicle-side charging socket 1. The charging socket 1 is configured for connection to a charging plug, not shown in detail. The charging plug and the charging socket 1 are each a component of a charging infrastructure for an electric vehicle or a hybrid vehicle. For this purpose, the charging plug, not shown, is inserted into the charging socket 1 in the direction of the arrow S schematically shown in FIG. 2, which shows the plug-in direction S, which is important here, for connecting the charging socket 1 and the charging plug.

[0038] The charging socket 1 is equipped with a housing 2, 3, which comprises a front cover 2 and a rear cover or rear cover 3 which can be connected thereto, which can be connected in particular to the corresponding Figure 1 2 . A plurality of electrical contact elements 4 are also arranged and provided in the housing 2, 3, which are contact elements 4 for the DC charging process. For this purpose, the electrical contact elements 4 are respectively electrically and thermally connected to a connector 5, which can be seen in particular from the view in FIG. 2 . The corresponding electrical contact elements 4 and connectors 5 can in principle also be formed in one piece, and according to this embodiment are anyway electrically and thermally connected to each other as described.

[0039] In addition to the electrical contact elements 4 for the DC charging process already mentioned, further contact elements 6 are provided, which are required for the AC charging process, but this is not important for the following discussion. Rather, the electrical contact elements 4 for the DC charging process are considered, since this is accompanied by high current intensities.

[0040] Additionally and importantly, a passively cooled heat pipe 7 is also provided, which is a "heat pipe" or metal pipe as described at the beginning according to this embodiment, which preferably has a sealed connection volume as described above and has a working medium for heat transfer therein. For this purpose, the metal pipe or heat pipe 7 has a defined length and is constructed in a closed manner at both ends. In order to carry out heat transfer, the relevant heat pipe 7 is thermally connected to the contact element 4 or the connector 5 with one end 7a thereof. The other end 7b of the passively cooled heat pipe 7 is thermally connected to the cooling body 8, as can be best seen from Figure 2. According to this embodiment, two electrical contact elements 4 (DC charging process) are provided, which are thermally connected to a common cooling body 8 respectively through the associated two heat pipes 7. As a result, a thermally conductive connection of the relevant electrical contact element 4 or the associated connector 5 to the cooling body 8 is provided through the passively cooled heat pipe 7.

[0041] It is now particularly important that the heat pipe 7 passes through the housing openings 2a, 3a according to the invention. In practice, the housing opening 2a in question is located on the one hand in the front housing or front cover 2, and on the other hand in the rear housing or rear cover 3, as can be seen in FIG. Figure 1 2 . This is, of course, merely exemplary and not restrictive. In any case, the following design is adopted in this way, that is, the heat pipe 7 passes through the relevant housing opening 2a, 3a, and thus the cooling body 8 can be arranged in the outer area, that is, outside the housing 2, 3. In the outer area of ​​the housing 2, 3, the cooling body 8 can particularly effectively discharge heat to the ambient air by convection, as already described at the beginning.

[0042] Since the heat pipe 7 is designed as a metal pipe in this embodiment and is connected to the contact element 4 or the connector 5 electrically connected to the contact element in a thermally conductive manner and thus electrically connected, an electrical insulation 9 is additionally provided, namely at least in the outer region and relative to the heat sink 8 arranged there. The electrical insulation 9 is a jacket made of plastic of the heat pipe 7 or the metal pipe according to this embodiment, which can be applied to the relevant pipe in connection with the plastic injection molding process. In any case, the electrical insulation 9 is located in the outer region and relative to the heat sink 8 arranged there and enters the interior of the housing 2, 3 through the housing openings 2a, 3a. This can be seen in particular from FIG. 2, from which it can be clearly seen that the electrical insulation 9 enters the interior of the housing 2, 3 through the relevant openings 2a, 3a by a few millimeters to 1 cm or more. In this way, the electrical insulation 9 made of plastic simultaneously serves as a seal of the housing openings 2a, 3a, so that the housing 2, 3 is designed to be water-proof.

[0043] The electrical insulation 9 is made of the plastic mentioned and described at the outset and is therefore designed to be electrically insulating and at the same time thermally conductive. For this purpose, the plastic in question can be provided with a corresponding filler likewise described at the outset. In any case, the electrical insulation 9 ensures overall that the relevant heat pipe 7 in the outer region of the housing 2, 3 does not carry voltage and therefore cannot be passed through by current, while nevertheless simultaneously allowing for the required heat pipe from the electrical contact element 4 via the heat pipe 7 to the heat sink 8.

[0044] It can be seen that the heat pipe 7 is inserted with one end 7a thereof into the contact element 4 or the associated connection piece 5, i.e. into a corresponding hollow hole in the connection piece 5 adapted to the heat pipe 7. Inside the housing 2, 3, the heat pipe 7 is substantially perpendicular to the contact element 4 and thus perpendicular to the longitudinal extension direction of the connection piece 5. Consistently, the relevant heat pipe 7 also has a substantially perpendicular arrangement relative to the plug-in direction S already described above.

[0045] Therefore, the heat pipe 7 is introduced into the upper opening 5a of the connecting piece 5 of the contact element 4 in an arc shape and is embedded in the upper opening 5a in the embodiment according to FIG2. Since the connecting piece 5 and the contact element 4 are each cylindrically configured according to this embodiment, the upper opening 5a is designed as a semi-cylindrical opening in the variant according to FIG2. Of course, this is only exemplary and not restrictive.

[0046] In the variant according to FIG. 3 , the heat pipe 7 is embedded substantially linearly in the upper opening 5 a, also realized in this case, of the connection piece 5 of the contact element 4. The upper opening 5 a in question is designed in this case as a cylindrical hole or hollow cylindrical hole, since the heat pipe 7 is tubular or cylindrical in design according to this embodiment. In both cases, the heat pipe 7 is thermally coupled to the connection piece 5 and thus to the contact element 4 in this way.

[0047] In order to improve the heat dissipation of the cooling body 8, the cooling body is equipped with an additional cooling device 10 according to this embodiment. The cooling device 10 is exemplarily a fan 10. Here, the fan 10 can be electrically controlled by the control unit, that is, it is controlled at least during the charging process through the two electrical contact elements 4. In principle, the control unit can also operate the cooling device or fan 10 for a certain and adjustable time after the charging process is completed, so as to avoid possible overheating of the cooling body 8 from the beginning. For this purpose, the fan 10 or the cooling device 10 is installed on the head side of the cooling body 8, so that the air sucked by the fan 10 flows through the individual fins arranged inside the cooling body 8 in the longitudinal direction of the cooling body.

[0048] List of reference numerals:

[0049] Charging socket 1

[0050] Front cover 2

[0051] Housing openings 2a, 3a

[0052] Shell 2, 3

[0053] Front cover 2

[0054] Back cover 3

[0055] Contact element 4

[0056] Connector 5

[0057] Opening 5a

[0058] Contact element 6

[0059] Heat pipe 7

[0060] End 7a

[0061] End 7b

[0062] Cooling body 8

[0063] Insulation part 9

[0064] Cooling device 10

[0065] Fan 10

[0066] Arrow S

[0067] Plug direction S

Claims

1. A plug connector for mechanical and electrical connection with a mating plug connector, the plug connector being in particular for a motor vehicle-side charging socket (1) for connection with a charging plug as a component of a charging infrastructure for an electric vehicle or a hybrid vehicle, the plug connector comprising: a housing (2, 3); at least one electrical contact element (4) arranged in the housing (2, 3); at least one heat pipe (7) preferably for passive cooling, the at least one heat pipe being connected with one end (7a) thereof to the contact element (4) and having a cooling body (8) at its other end (7b), It is characterized in that The at least one heat pipe (7) passes through a housing opening (2a, 3a) and is provided outside the housing (2, 3) with a cooling body (8) arranged there.

2. The connector according to claim 1, characterized in that: The heat pipe (7) has an electrical insulation (9), in particular outside the housing (2, 3) and relative to a cooling body (8) arranged there.

3. The connector according to claim 2, characterized in that: The electrical insulation (9) passes through the housing opening (2a, 3a) into the interior of the housing (2, 3).

4. The plug connector according to any one of claims 1 to 3, characterized in that: The cooling body (8) is equipped with additional cooling means (10).

5. The connector according to claim 4, characterized in that: The cooling device (10) is designed, for example, as an electrically driven fan (10).

6. The plug connector according to any one of claims 1 to 5, characterized in that: The heat pipe (7) is designed as a metal pipe, in particular, said pipe encloses a tightly closed volume.

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

8. The plug connector according to any one of claims 1 to 7, characterized in that: The heat pipe (7) is inserted with one end (7a) thereof into the contact element (4) or a connector (5) electrically connected thereto.

9. The plug connector according to any one of claims 1 to 8, characterized in that: The heat pipe (7) is substantially perpendicular to the longitudinal extension direction of the contact element (4).

10. The plug connector according to any one of claims 1 to 9, characterized in that: The heat pipe (7) is embedded in an arcuate or substantially straight line in an upper opening (5a) of the connecting piece (5) of the contact element (4).

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