Plug connector part

Abstract

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 (1) for coupling to a charging plug as components of an electric charging infrastructure for electric or hybrid motor vehicles, or vice versa. The basic structure of the plug connector part has a housing (2) and at least one electric contact element (3) which is arranged in the housing (2). Additionally, a heat transfer element (5, 6) is provided which thermally contacts the electric contact element (3). According to the invention, at least one housing (2) region (5) which extends up to the contact element (3) is designed as a heat transfer element (5, 6).

Description

[0001] Description

[0002] 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 heat transport element which is in thermal contact with the electrical contact element.

[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. The charging plug (like the charging socket) is part of an electrical charging infrastructure that can be used to charge the rechargeable energy storage devices or batteries 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, the electric or hybrid vehicle has 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 charge the respective motor vehicle.

[0005] In order to supply the high electrical power required by the electric motors in the vehicle in question and to provide sufficient range, high-voltage batteries or accumulators are used today. These batteries are typically charged with high-voltage direct current. In addition to such DC charging processes (direct current), most electric or hybrid vehicles also allow the charging process to be carried out using an alternating voltage in the sense of an AC charging process (alternate current). In this case, however, low currents and long charging times are usually used, whereas the DC charging process described above involves high voltages and high currents and the resulting short charging times.Especially with DC charging processes, the high current intensity causes the electrical contact elements used at this point to become increasingly hot. This increases their resistance, which hinders the electrical charging process and the desired fast charging.

[0006] For this reason, the prior art according to EP 3 616 270 B1 describes a connector part including a temperature monitoring device. The temperature monitoring device ensures that the current is shut off or at least reduced in the event of any overheating of the contact element.

[0007] The generic prior art according to EP 3 433 904 B1 involves equipping the contact element with a heat capacity element or a heat transfer element. This is intended to optimize and accelerate heat dissipation from the contact element to the environment. In the best case scenario, this allows high currents to be transmitted without triggering a possible and additionally provided temperature monitoring device. This has proven to be fundamentally successful.

[0008] However, the prior art according to EP 3 433 904 B1 generally proceeds in such a way that the heat capacity elements of different contact elements are not only electrically insulated from one another, but are usually also connected to a shaft section of the contact element via an attachment piece, either force-fitting or form-fitting. Furthermore, the heat capacity elements are solid, cuboid-shaped bodies. As a result, the available installation space inside the connector part or the charging socket is reduced, resulting in an overall increase in weight and, at the same time, increased costs. This is no longer acceptable given the general requirements in the automotive sector for weight savings and cost optimization. This is where the invention comes in.

[0009] The invention is based on the technical problem of further developing such a connector part in such a way that a compact design with cost advantages compared to the prior art is observed.

[0010] To solve this technical problem, a generic connector part within the scope of the invention is characterized in that at least one region of the housing reaching the contact element is designed as a heat transport element.

[0011] The area in question, which extends to the contact element, is usually designed to enclose the contact element. Furthermore, the approach is such that the area in question, which forms the heat transfer element, has a higher thermal conductivity than the rest of the housing. This requires special measures because the area in question, like the housing as a whole, is made of plastic, and any heat transfer is therefore rather slow.

[0012] In this way, a compact design is firstly provided and implemented, because the required and obligatory housing (made of plastic) for the connector part or the charging socket typically implemented at this point also functions and is designed as a heat transfer element or heat capacity element, at least in the area adjacent to the contact element. This expressly eliminates the need for complex and bulky additional heat transfer elements. The invention as a whole is based on the realization that the housing for the connector part is usually made of a thermoplastic. In this case, a design as a plastic injection-molded part has proven particularly advantageous. Such thermoplastics such as PP (polypropylene), PA (polyamide), PBT (polyethylene terephthalate), PE (polyethylene), etc.Typically, they have thermal conductivities of, for example, 0.23 W / (m ■ K) for polypropylene (PP) or up to 0.35 W / (m ■ K) for polyamides. Values ​​of approximately 0.5 W / (m ■ K) are observed for polyethylene.

[0013] According to the invention, the housing region that functions as a heat-transfer element and extends to the contact element can be manufactured from a modified plastic in such a way that the plastic used is one with embedded fillers to increase thermal conductivity. Suitable fillers in this context can be those that are electrically insulating and simultaneously thermally conductive. These include, for example, 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 3.

[0014] In this context, the relevant thermally conductive fillers in the plastic can be provided in a grammage of up to 50 wt% and more, so that overall thermal conductivities of significantly more than 1 W / (m ■ K) can be achieved. Further details on this and on suitable fillers and plastics can be found in the relevant and applicable prior art according to DE 10 2007 037 316 A1, which deals with thermally conductive and electrically insulating thermoplastic compounds, i.e., plastics with embedded fillers. Reference may also be made at this point to DE 10 2013 208 605 A1.

[0015] In addition to the possibility of equipping the region of the plastic housing in question, which is designed as a heat transport element, with embedded fillers and thus increased thermal conductivity, the invention provides, as a further alternative or additional possibility, for the region in question to have at least one channel with a fluid located therein. The fluid is generally designed to be both thermally conductive and electrically insulating. Suitable fluids in this context are, for example, oils and, in particular, so-called transformer oils. To further improve thermal conductivity, the invention additionally proposes in this context that the channel in question have at least one path outside the region and the housing containing it. This can further improve heat dissipation.

[0016] The area of ​​the housing in question, which functions as a heat transfer element or heat capacity element, is typically a flange that accommodates the contact element. The flange generally has a predominantly vertical plane extension compared to the contact element that passes through the flange. This means that the longitudinal extension of the contact element and the extension of the plane forming the flange are predominantly perpendicular to each other.

[0017] In this context, it is also possible to embed the flange in question in a surrounding front cover of the housing. The front cover of the housing may, like the rest of the housing, be made of the thermoplastic material without embedded fillers. This means that the incorporation of the fillers is essentially limited to the area or flange. Of course, it is also within the scope of the invention for the entire housing to be made of the modified thermoplastic material with the embedded fillers. For cost reasons, however, the incorporation of the fillers will be limited to the area that functions as a heat transfer element and extends to the contact element, or rather, to the flange of the housing.

[0018] The result is a connector part for mechanically and electrically connecting to a mating connector part and, in particular, a charging socket on the motor vehicle side that does not require any protruding attachments or fittings and can be manufactured at a particularly low cost. This is ensured on the one hand by the fact that the plastic with the embedded fillers, as well as the plastic for the rest of the housing, can be manufactured and processed by plastic injection molding. Furthermore, the ingredients required at this point, i.e. the fillers as well as the fluid used in the channel, are inexpensive, so that in addition to a particularly compact design, a lower manufacturing cost compared to the state of the art is achieved. These are the main advantages.

[0019] The invention is explained in more detail below with reference to a drawing which merely represents an exemplary embodiment; in the drawings:

[0020] Fig. 1 shows the connector part according to the invention in the form of a motor vehicle charging socket in a front view,

[0021] Fig. 2 the corresponding rear view to Fig. 1 ,

[0022] Fig. 3 shows the object according to Figs. 1 and 2 in individual views and Figs. 4A-4C show another modified embodiment.

[0023] The figures show a connector part for mechanically and electrically connecting to a mating connector part. In fact, the connector part according to the exemplary embodiment in Figs. 1 and 2 is a motor vehicle-mounted charging socket 1. The charging socket 1 is designed for coupling to a charging plug, which is not shown in detail and represents a component of an electrical charging infrastructure for electric or hybrid motor vehicles.

[0024] For this purpose, the charging socket 1 is equipped with a plastic housing 2 and at least one electrical contact element 3 arranged within the housing 2. In the following, only the two contact elements 3 required for a DC charging process will be examined in more detail. The additional electrical contact elements 4, which are required for an AC charging process, will not be discussed in detail. According to the exemplary embodiment, the two electrical contact elements 3 inside the housing 2 are equipped with a heat transfer element 5, 6. The heat transfer element 5, 6 is in thermal contact with the electrical contact element 3.

[0025] For this purpose, at least one region 5 of the housing 2 extending to the contact element 3 is designed as a heat transport element 5. It can be seen that the region 5 in question or the heat transport element 5 encloses the contact element 3, as the illustration in Fig. 3 clearly shows. For this purpose, the region 5 in question has increased thermal conductivity compared to the rest of the housing 2. The invention achieves this in such a way that the region 5 in question is made of a plastic with embedded fillers to increase the thermal conductivity. In fact, the region 5, which is designed as a flange 5 receiving the contact element 3, is produced by injection molding from a thermoplastic such as PP, PE, etc., as well as embedded fillers in the form of, for example, aluminum oxide or boron nitride.This is achieved by ensuring that the flange 5 in question has a predominantly vertical plane extension compared to a longitudinal extension L of the contact element 3. In fact, the contact element 3 is a cylindrical loading pin in the exemplary embodiment. The flange 5 made of plastic with embedded fillers is penetrated by the contact element 3 in question. For this purpose, the flange 5 according to the exemplary embodiment is additionally equipped with radial ribs 5a surrounding the contact element 3, which are connected to the flange 5. Furthermore, it can be seen that the flange 5 in question is embedded in a surrounding front cover 2a of the housing 2, as the illustration in Fig. 3 immediately makes clear.

[0026] In a variant illustrated in Figs. 4A to 4C, the heat transfer element 5, 6 is designed as a fluid 6. The fluid 6 in question is located in a channel 7, which is provided for this purpose in the region of the housing 2 designed as a heat transfer element 5 or flange 5. The fluid 6 in question inside the channel 7 can be one that is both thermally conductive and electrically insulating. Typically, oil, and in particular transformer oil, is used in this case.

[0027] It can be seen from Fig. 4C that the channel 7 can also be equipped with a path 7a outside the area 5 in question or the flange 5 and consequently also outside the housing 2. In this way, particularly effective heat dissipation via the path 7a outside the housing 2 of the charging socket 1 is provided and observed. A total of two different circuits and associated channels 7 can be realized for the two contact elements 3 shown, as can be seen from Fig. 4A. Fig. 4B shows another possible routing of the fluid 6 within the channel 7 or the multiple channels 7.

[0028] List of reference symbols

[0029] Charging socket 1

[0030] Housing 2 Contact element 3, 4

[0031] Heat transfer element 5, 6

[0032] Flange 5

[0033] Radial ribs 5a

[0034] Fluid 6 channel?

[0035] Path 7a

[0036] Contact element 8

Claims

Patent claims 1. Connector part for mechanical and electrical connection with a mating connector part, in particular a vehicle-side charging socket (1) for coupling with a charging plug as components of an electric charging infrastructure for electric or hybrid vehicles, or vice versa, with a housing (2) made of plastic and at least one electrical contact element (3) arranged in the housing (2), and with a heat transfer element (5, 6) which is in thermal contact with the electrical contact element (3), characterized in that at least one area (5) of the housing (2) extending towards the contact element (3) is designed as a heat transfer element (5).

2. Connector part according to claim 1, characterized in that the area (5) surrounds the contact element (3).

3. Connector part according to claim 1 or 2, characterized in that the area (5) has an increased thermal conductivity compared to the rest of the housing (2).

4. Connector part according to one of claims 1 to 3, characterized in that the area (5) is made of a plastic with embedded fillers to increase thermal conductivity.

5. Connector part according to one of claims 1 to 4, characterized in that the area (5) has at least one channel (7) with a fluid (6) located therein.

6. Connector part according to claim 5, characterized in that the channel (7) has a path (7a) outside the area (5) and outside the housing (2).

7. Connector part according to claim 5 or 6, characterized in that the fluid (6) is thermally conductive and electrically insulating, for example as oil.

8. Connector part according to one of claims 1 to 7, characterized in that the area (5) is designed as a flange (5) receiving the contact element (3).

9. Connector part according to claim 8, characterized in that the flange (5) has a predominantly vertical plane extent compared to the contact element (3) extending through the flange (5).

10. Connector part according to one of claims 1 to 9, characterized in that the flange (5) is embedded in a front cover (2a) of the housing (2) surrounding it.

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