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 vehicle-side charging socket (1) for coupling to a charging plug as components of an electrical charging infrastructure for electric or hybrid motor vehicles. For this purpose, the plug connector part is equipped with: a housing (2); at least one electrical contact element (3) located in the housing (2); and a temperature-monitoring device (5, 6) having at least one planar carrier element (5) and at least one temperature sensor (6) located thereon for the contact element (3). The carrier element (5) can be thermally coupled to the contact element (3) with the aid of at least one spring element (8). According to the invention, the carrier element (5) is positioned tangentially on the contact element (3).

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 and at least one electrical contact element arranged in the housing, and with a temperature monitoring device with at least one flat carrier element and at least one temperature sensor arranged thereon for the contact element, wherein the carrier element can be thermally coupled to the contact element by means of at least one spring 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 (and also 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 performance of the electric motors in the vehicle in question with the required electrical energy and to provide a sufficient range, high-voltage batteries or accumulators are typically used today. These batteries are typically charged with high-voltage direct current. In addition to such DC (direct current) charging processes, most electric or hybrid vehicles also allow the charging process to be carried out using an alternating voltage in the sense of an AC (alternating current) charging process. 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, consequently, short charging times.

[0006] 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.

[0007] For this reason, the generic prior art according to EP 3 616 270 B1 describes a connector part including a temperature monitoring device. For this purpose, the temperature monitoring device has a support element extending flatly along a plane, on which the sensor device or temperature sensor is arranged. Furthermore, the support element is equipped with two clip arms, via which the support element is clipped onto the contact element whose temperature is to be monitored.

[0008] Another approach according to EP 3 286 804 B1 involves a connector part which is again equipped with a carrier element. The carrier element is used to detect heating of the at least one contact element. For this purpose, the contact element extends through at least one opening in the carrier element. The prior art has generally proven effective when it comes to detecting and evaluating any heating of the contact element of the connector part using the temperature monitoring device. For this purpose, the temperature monitoring device is typically connected to a control unit, for example to ensure rapid shutdown in the event of overheating. This prevents any damage to the connector part and in particular to the associated housing, which is usually made of plastic.

[0009] However, it is noticeable that the known embodiments of the carrier element generally require a special design with regard to the contact element to be monitored for temperature. This applies particularly to the clips provided in the generic prior art according to EP 3 616 270 B1, with which the carrier element is clipped onto the contact element. Such clips must be adapted to the geometry of the contact element and can often only be connected to the electrical contact element in a specific mounting position. The invention aims to remedy this situation.

[0010] The invention is based on the technical problem of further developing a connector part of the structure described above in such a way that a flexible attachment of the temperature monitoring device to the electrical contact element to be monitored is possible while taking into account simple assembly.

[0011] To solve this technical problem, a generic connector part for mechanically and electrically connecting to a mating connector part is characterized in that the carrier element is arranged tangentially to the (cylindrical) contact element when viewed from the front. Therefore, in the context of the invention, the carrier element is not directly connected to the contact element, for example, in order to provide the required thermal coupling and thus temperature monitoring, as is the case with the clips according to EP 3 616 270 B1 in the prior art. Rather, the invention relies on a contacting of the carrier element with the cylindrical contact element in such a way that the carrier element is arranged tangentially to the cylindrical contact element or the carrier element tangentially touches the cylindrical contact element.

[0012] In this way, the carrier element and, with it, the temperature sensor arranged on the carrier element can be flexibly mounted on the cylindrical contact element. This is because it is only necessary for the carrier element to tangentially touch the contact element or to rest against it. This generally allows for different mounting directions, depending on the observed and prevailing installation conditions. Furthermore, the inventive design expressly does not require a specific adaptation of the carrier element to the geometry of the cylindrical contact element—unlike the prior art.

[0013] Rather, the diameter of the cylindrical contact element ultimately plays virtually no role in the tangential engagement of the carrier element. Furthermore, within the scope of the invention, it is sufficient if the contact element is cylindrical, at least in the contact area with the carrier element, so that the carrier element can be arranged tangentially to the cylindrical contact element or the cylindrical area of ​​the contact element. This gives the contact element a wide range of design freedom. The same applies to the connector part itself and the associated housing, which the prior art cannot provide.

[0014] According to a further advantageous embodiment, the contact element has an insulating collar on the housing side with an insertion opening for the carrier element. The invention is based on the knowledge that a high-voltage direct current is applied to the contact element or, in most cases, the two contact elements provided at this point. In order to achieve the appropriate spacing and required electrical insulation at this point, the contact element in question is equipped with the insulating collar on the housing side, i.e., inside the housing, usually up to a connection area of ​​the contact element. The contact element is typically a contact socket because the connector part is usually designed as a charging socket on the motor vehicle.

[0015] The insulating collar now ensures that the contact element or contact socket is covered almost completely with the insulating collar except for the insertion opening for the carrier element, so that only a contact plug as part of the charging plug can be inserted into the contact socket and ensures the required electrical contact. Nevertheless, the carrier element can be easily installed. All that is required is that the carrier element reaches through the insertion opening in the insulating collar and is thus placed tangentially against the contact element or its cylindrical area. The at least one spring element or usually the several spring elements ensure that the carrier element is positioned accordingly and is held in contact with the cylindrical contact element inside the insertion opening with the required force.

[0016] The insulating collar is usually a component of the housing and, like the housing, may be made of plastic, for example, forming a one-piece plastic injection-molded part with the housing. In principle, however, the insulating collar can also be provided separately from the housing. In this case, for example, the contact element can be held by the insulating collar and the assembly formed in this way can be installed in the housing using, for example, notches. Furthermore, the insertion opening is usually sized to match the support element or temperature sensor. This means that the size of the insertion opening typically corresponds to the external dimensions of the support element or temperature sensor, so that when the support element is installed in the insertion opening, no uncovered areas of the contact element are observed.This is further enhanced by the fact that the carrier element has a sheath that is both thermally conductive and electrically insulating, so that the contact element is covered in an electrically insulating manner by means of the insulating collar and by the carrier element, which is also equipped with the insulating sheath.

[0017] The carrier element is typically a sensor board with conductor tracks for electrically transmitting sensor signals. In reality, a printed circuit board made of an electrically non-conductive carrier material, such as plastic, is usually used here. It is equipped with printed or embedded conductor tracks. Signals from the temperature sensor can be transmitted via the conductor tracks, for example, to a control unit connected to the carrier element via a supply line.

[0018] The temperature sensor is typically a semiconductor sensor or a resistance sensor, which can, for example, have a positive temperature coefficient in the sense of a PTC resistor. In such temperature sensors, the resistance value increases with rising temperature. Colloquially, these temperature sensors are also referred to as PTC thermistors and can, for example, be made of a ceramic material as so-called ceramic PTC thermistors. However, it is also conceivable to use electrical resistors with a negative temperature coefficient, so-called NTC resistors, as temperature sensors. In this case, the resistance of the temperature sensor in question decreases with rising temperature. The temperature sensor is usually located at the end of the carrier element, on its top or bottom side. The carrier element itself is designed as a rectangular strip.By attaching the temperature sensor to the end of the rectangular strip, the temperature sensor can be positioned such that it comes into direct thermal contact with the cylindrical contact element or the cylindrical region of the contact element when the carrier element is arranged tangentially to the contact element. In principle, however, it is also possible for the temperature sensor to be positioned not at the end, but rather in the center of the carrier element. In this case, the carrier element may be equipped with a metal core, which conducts heat from the contact surface of the carrier element with the contact element to the temperature sensor. In this case, the carrier element is designed, for example, as a so-called metal-core circuit board, as described in detail in DE 39 35 680 A1.In this case, a metal plate is covered with plastic on the inside and additional conductor tracks can be applied, for example, photolithographically, as described in detail in the previously mentioned prior art.

[0019] Typically, however, the sensor board or printed circuit board made of plastic with applied or embedded conductor tracks and without an additional metal core is used as the carrier element. This is because the temperature sensor located on the carrier element or printed circuit board is generally positioned at the contact surface between the carrier element and the contact element, so that the heat flow emanating from the contact element reaches the temperature sensor directly and almost instantaneously.

[0020] At this point, however, the heat flow emanating from the contact element must first pass through the casing that typically surrounds the carrier element, which, according to the invention, is designed to be both thermally conductive and electrically insulating. The casing is designed to enclose the sensor board or circuit board and the temperature sensor together. The casing is typically made of plastic.

[0021] For this purpose, the coating typically uses a compound that initially uses a thermoplastic material such as PA (polyamide), PBT (polybutylene terephthalate), PP (polypropylene), PPS (polyphenylene sulfide), or similar thermoplastics. These are particularly easy to process by injection molding. A filler is then added to the plastic or plastic compound in question to form a plastic coating. Suitable fillers include graphite, carbon fiber, or even ceramic.

[0022] In fact, thermosets or thermoplastics equipped with electrically insulating, thermally conductive fillers are advantageously used here. Aluminum compounds or boron compounds, preferably aluminum oxide or boron nitride, have proven particularly suitable. The grammage of these electrically insulating and thermally conductive fillers in the plastic can be up to 50 wt. % and more. Thermal conductivities of more than 1 W / (m ■ K) up to 25 W / (m ■ K) can be achieved. Further details with regard to such plastics can be found in the prior art according to DE 102007 037 316 A1, which is cited here as a reference. Similar information can be found in DE 10 2013 208 605 A1.

[0023] At this point, the invention further recommends that the casing for the carrier element, including the temperature sensor, typically have a material thickness of less than 1 mm, in particular 0.5 mm or less. This ensures very rapid heat transfer from the contact element to the temperature sensor, so that any overheating at this point can be immediately detected and, for example, result in a power shutdown. Finally, the invention recommends a special design of the carrier element, namely one in which the carrier element is equipped with two opposing temperature sensors. In this case, for example, two contact elements for a DC charging process can be temperature-monitored simultaneously with a (single) carrier element.It goes without saying that by using the two opposing temperature sensors, the two contact elements can be monitored separately for any overheating. As soon as signs of such overheating occur and are observed on one of the two contact elements, the control unit supplied with the sensor signals interprets this as a shutdown or a current reduction. It goes without saying that the two opposing temperature sensors are again arranged in the area of ​​the contact surface of the carrier element with the associated contact element in order to realize and implement temperature measurement with the least possible delay.

[0024] Finally, the design is usually such that the conductor track or multiple conductor tracks, as components of the carrier element or the sensor board or printed circuit board implemented at this location, define one or more contact areas. The sensor signals can then be transmitted to the control unit particularly advantageously via these contact areas and the spring elements that generally enclose the contact areas on at least one side. It is understood that the contact areas in question are not covered by the casing of the sensor board, including the temperature sensor, so that the spring elements can make direct electrical contact with the contact areas in question during assembly of the carrier element.

[0025] This means that, according to the invention, the spring elements perform a dual function: firstly, they hold the respective support element in tangential contact with the contact element to be monitored. Secondly, the spring elements also function as electrical contacts, namely to transmit the sensor signals from the temperature sensor attached to or on the support element to the control unit. In principle, it is of course also conceivable and within the scope of the invention for additional contact areas to be implemented at this location, which do not necessarily serve to transmit the sensor signals from the temperature sensor.

[0026] The result is a connector component, and in particular a vehicle-mounted charging socket with a temperature monitoring device, in which the temperature monitoring device can be adapted particularly flexibly to different installation situations and designs of the respective charging socket. This is essentially due to the fact that the temperature monitoring device uses at least one flat support element, which is arranged tangentially to the cylindrical contact element for this purpose. This eliminates the need for special fastenings on the contact element or specific mounting directions, which explains the particular flexibility. These are the key advantages.

[0027] The invention is explained in more detail below with reference to a drawing which merely represents an exemplary embodiment; in the drawings:

[0028] Fig. 1 shows the connector part according to the invention in the form of a motor vehicle charging socket in a front view,

[0029] Fig. 2 the corresponding rear view to Fig. 1 ,

[0030] Fig. 3 shows the object according to Fig. 2 in an enlarged detail and

[0031] Figures 4A to 4C show the assembly of an alternatively used carrier element as a temperature monitoring device. 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 Figures 1 and 2 is a motor vehicle-mounted charging socket 1. The charging socket 1 is configured 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.

[0032] For this purpose, the charging socket 1 is equipped with a plastic housing 2 and at least one electrical contact element 3 arranged in the housing 2. Only the two contact elements 3 required for a DC charging process will be considered below. The additional electrical contact elements 4, on the other hand, are required for an AC charging process and will not be discussed in detail below.

[0033] As shown in Figures 3 and 4, the two contact elements 3 are equipped with a temperature monitoring device 5, 6. For this purpose, the temperature monitoring device 5, 6 has at least one flat support element 5 and at least one temperature sensor 6 arranged thereon for the contact element 3.

[0034] Figures 3 and 4 show that the carrier element 5 is flat and designed as a rectangular strip or rectangular element. It is also clear that the temperature sensor 6 is arranged on a surface of the carrier element 5, specifically at the end of the carrier element 5 in the region of a contact surface 7 with the contact element 3.

[0035] The support element 5 is held by means of several spring elements 8, thus ensuring that the support element 5 is thermally coupled to the contact element 3. As shown in Figures 4A to 4C, the respective spring elements 8 are U-shaped springs that surround the edges of the rectangular support element 5. According to the exemplary embodiment, the individual spring elements 8 not only serve to hold the support element 5, but are also connected to electrical lines 9 (only indicated in Figure 3), which in turn are connected to a control unit 10.

[0036] According to the invention, the carrier element 5 is arranged tangentially to the contact element 3, specifically in a front view of the contact element 3. For this purpose, the contact element 3 is cylindrical, at least in the region of the contact surface 7. This allows the temperature sensor 6 to come into direct thermal contact with the contact element 3.

[0037] It can be seen, particularly from Figures 3 and 4A to 4C, that the contact element 3 is enclosed on the housing side by an insulating collar 11, which has an insertion opening 12 for the carrier element 5 or the temperature sensor 6 on the carrier element 5 engaging in the insertion opening 12. The insulating collar 11 can be made integrally with the housing 1, also from plastic. In principle, however, the insulating collar 11 and the contact element 3 can also represent a pre-assembled assembly 3, 11, which is connected to the rest of the housing 1, for example, by a snap-in connection. However, this is not shown in detail.

[0038] The insertion opening 12 is sized to fit the support element 5 or the temperature sensor 6 carried by the support element 5. The support element 5 is a sensor board or printed circuit board equipped with conductor tracks for electrically transmitting sensor signals from the temperature sensor 6. According to the exemplary embodiment, the conductor tracks terminate in contact areas 13, which can be seen particularly in Fig. 3. The spring elements 8 engage around the support element 5 in these contact areas 13, so that in this way not only is the support element 5 held in tangential contact with the respective contact element 3, but at the same time the sensor signals emitted by the temperature sensor 6 can be transmitted to the control unit 10 via the spring elements 8 and the supply lines 9.

[0039] The carrier element 5 and the temperature sensor 6 are equipped with a casing 14 that is both thermally conductive and electrically insulating. The casing 14 is designed such that only the previously mentioned contact areas 13 are left out. This means that the casing 14 encloses the sensor board or printed circuit board and thus the carrier element 5 and the temperature sensor 6 together. For this purpose, the casing 14 is a plastic casing that is applied by overmolding the carrier element 5 including the temperature sensor 6. In fact, the invention at this point relies on a thermoplastic material, as already described in the introduction to the description. In detail, the plastic material is a plastic compound with added fillers.

[0040] Fillers are used that simultaneously ensure good thermal conduction and electrical insulation of the thermoplastic material in question, for example, in the form of aluminum oxide or boron nitride, as already described in the introduction. This allows the plastic casing 14 to still be processed by injection molding, while simultaneously ensuring that the casing 14 virtually does not impede thermal conduction from the contact element 3 to the temperature sensor 6 in the area of ​​the contact surface 7. Nevertheless, the casing 14 provides the necessary electrical insulation in this area, so that any problems at this point are not observed.

[0041] In fact, the casing 14 according to the exemplary embodiment has a material thickness that is generally less than 1 mm, and in particular 0.5 mm or less. This allows a heat flow emanating from the contact element 3 to pass through the casing 14 directly and quickly, reaching the temperature sensor 6 in the area of ​​the contact surface 7 with virtually no delay. As a result, any overheating of the contact element 3 is immediately detected by the temperature sensor 6 and reported to the control unit 10 as described. The control unit 10 can then, for example, reduce the charging current at the contact elements 3 or even switch it off entirely.

[0042] Figures 4A to 4C depict a variant in which the carrier element 5 is equipped with two opposing temperature sensors 6. In this way, the two adjacent contact elements 3 can be monitored for temperature using a single carrier element 5 with the two temperature sensors 6. The sequence in Figures 4A to 4C shows the simple assembly of the carrier element 5 including the two temperature sensors 6, which for this purpose are plugged into the spring elements 8 anchored in the housing. This simultaneously creates the desired electrical connection between the spring elements 8 and the associated contact areas 13 of the conductor track of the carrier elements 5, so that in this case too, the two temperature sensors 6 can independently monitor the associated contact elements 3 for any overheating. This means thatIn this case too, the two contact elements 3 are monitored separately using the associated temperature sensors 6 and any overheating is reported to the control unit 10 as described.

[0043] List of reference symbols:

[0044] 1 charging socket

[0045] 2 housings 3 electrical contact elements (DC)

[0046] 4 electrical contact elements (AC)

[0047] 5, 6 Temperature monitoring device

[0048] 5 flat support element

[0049] 6 Temperature sensor 7 Contact surface

[0050] 8 spring elements

[0051] 9 electrical cables

[0052] 10 Control unit

[0053] 11 Insulating collar 3, 11 Mounting assembly

[0054] 12 insertion opening

[0055] 13 contact areas

[0056] 14 Wrapping

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) and at least one electrical contact element (3) arranged in the housing (2), and with a temperature monitoring device (5, 6) with at least one planar support element (5) and at least one temperature sensor (6) arranged thereon for the contact element (3), wherein the support element (5) is thermally coupled to the contact element (3) by means of at least one spring element (8), characterized in that the support element (5) is arranged tangentially to the contact element (3).

2. Connector part according to claim 1, characterized in that the contact element (3) has an insulating collar (11) on the housing side with an insertion opening (12) for the carrier element (5).

3. Connector part according to claim 2, characterized in that the insertion opening (12) is adapted in size to the temperature sensor (6).

4. Connector part according to one of claims 1 to 3, characterized in that the carrier element (5) has a sensor board with conductor tracks for electrical transmission of sensor signals.

5. Connector part according to one of claims 1 to 4, characterized in that the carrier element (5) has a simultaneously thermally conductive and electrically insulating covering (14).

6. Connector part according to claim 5, characterized in that the covering (14) jointly encloses the sensor board and the temperature sensor (6).

7. Connector part according to claim 5 or 6, characterized in that the covering (14) is designed as a plastic covering.

8. Connector part according to claim 7, characterized in that a thermoset or a thermoplastic plastic with added filler is used as the plastic.

9. Connector part according to one of claims 5 to 8, characterized in that the covering (14) has a material thickness of less than 1 mm, in particular 0.5 mm and less.

10. Connector part according to one of claims 1 to 9, characterized in that the carrier element (5) is equipped with two opposing temperature sensors (6).

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