Plug-in connector element and plug-in connector for high voltage applications

Abstract

To provide a plug-in connector in which an enclosed plug-in connection portion is safe and reliable in operation and nevertheless which can be manufactured with high cost effectiveness.SOLUTION: A plug-in connector element for detachably electrical contacting with a mating plug-in connector element for a high voltage (HV) application comprises: at least one conductive contact element 134; a housing 136; and one contact protection element 116. The contact protection element is arranged so as to prevent an object having a diameter exceeding a defined value from reaching the conductive contact element between the housing and the contact protection element. The plug-in connector element has at least one temperature sensor which is at least partially housed in the contact protection element and which can be operated to detect temperature of the conductive contact element.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a plug-in connector element and an associated plug-in connector for high voltage (HV) applications.

Background Art

[0002] In electromobility, HV plug-in connectors with large conductive cross-sections are required for propulsion and for charging HV batteries. Temperature sensors are used in HV systems to shorten the charging time. There is also an increasing need for temperature sensors in HV plug-in connectors. The more accurate the temperature measurement in the plug-in connector, the better the adjustment of the charging parameters by the HV system, resulting in a shorter charging time. In conventional HV plug-in connectors, it is difficult to place the temperature sensor in the vicinity of the contact point (hereinafter also referred to as "hot spot"). In many cases, the only option left is to install the temperature measurement sensor in the crimping area (away from the hot spot) or on the current rail.

[0003] Figures 14 to 16 show a known HV plug-in connector configuration. Figure 14 shows a schematic cross-sectional view of the plug-in connector 200 in the inserted state. The plug-in connector 200 comprises a plug-in connector element 202 and a mating plug-in connector element 204. As shown, the plug-in connector element 202 is a socket element having a conductive spring-type contact element 210, and the mating plug-in connector element 204 is a plug-in element having a conductive blade contact 206.

[0004] Figure 15 shows the plug-in connector element 202 in perspective view. Figure 16 shows the mating plug-in connector element 204 in perspective view. Further, Figures 15 and 16 show the contact protection functionality in both connecting elements 202, 204, and a test probe 214 (known as a test finger), which is not allowed to contact the conductive part, is schematically shown in both cases.

[0005] Electrical contact between the plug-in connector element 202 and the mating plug-in connector element 204 takes place in the contact area 208, in which case the conductive spring contact element 210 is pressed onto the blade contact 206. In order to monitor the temperature of the contact area 208, the temperature sensors 212A, 212B should be attached as close as possible to the contact area 208. However, in the known configuration shown, due to spatial conditions, this is only possible in the connection area of the blade contact 206 (temperature sensor 212A) and / or in the crimp area of the socket element (temperature sensor 212B). However, for this reason, the distance to the actual occurrence area where a temperature increase may occur is too large, so that it is not possible to react quickly to overheating. As a result, for example, the battery has to be charged at a lower charging current for a longer time. SUMMARY OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION

[0006] Therefore, there is a need for a plug-in connector element that overcomes the disadvantages of known solutions such that the enclosed insertion connection is safe and reliable during operation and can nevertheless be manufactured cost-effectively. MEANS FOR SOLVING THE PROBLEM

[0007] This object is solved by the subject matter of the independent patent claims. Advantageous embodiments of the invention are the subject matter of the dependent patent claims.

[0008] The present invention is based on the idea of embedding at least one temperature sensor in or arranging it on the surface of a contact protection element instead of in a housing element in an HV plug-in connector. In this way, the temperature sensor can be directly arranged within the electrical contact area between the plug-in connector element and the mating plug-in connector element and thermally connected to the area where overheating may occur at the shortest possible distance.

[0009] In particular, the plug-in connector element for detachably making electrical contact with the mating plug-in connector element comprises at least one conductive contact element, one housing, and one contact protection element, and this contact protection element is arranged between the housing and the contact protection element so as to prevent an object having a diameter exceeding a specified value from reaching the conductive contact element. At least one temperature sensor at least partially accommodated within the contact protection element can be operated to measure the temperature of the conductive contact element.

[0010] This configuration has the advantage that the temperature sensor can be arranged neutrally and flexibly with respect to the installation space even in the immediate vicinity of the hot spot. The sensor is arranged at an optimal position within the contact protection element with respect to the contact arrangement. Depending on the mounting position, the necessary contact pressure of the sensor against the measurement surface is generated by the insertion process or during the assembly of the contact protection part. A reliable installation and routing of the connection line of the sensor into the contact protection element is also made possible. Using this solution, the temperature measurement of the HV plug-in connector becomes more accurate and more flexible.

[0011] Here, it is of course pointed out that not only a single temperature sensor but also a plurality of additional temperature sensors can be arranged within and / or on the contact protection element. Furthermore, a temperature sensor having two or more sensing regions may be provided.

[0012] In order to enable temperature monitoring in real time as much as possible, according to an advantageous embodiment, at least one temperature sensor is arranged to measure the temperature of the conductive contact element in a contact region where the conductive contact element can be in electrical contact through the mating conductive contact element of the mating plug-in connector element.

[0013] According to an advantageous aspect, the housing has an essentially cylindrical inner surface on which the conductive contact element is arranged, and the conductive contact element at least partially grips around the contact protection element. In this way, a particularly compact structure can be realized.

[0014] In this case, the contact protection element can have a columnar structure, and the temperature sensor is arranged on the outer wall of the contact protection element. Then, the temperature sensor makes a particularly close thermally conductive contact with the contact area, and in this area, the conductive contact element can make electrical contact through the mating conductive contact element of the mating plug-in connector element, and the achievable response time to a temperature rise is particularly short.

[0015] As an alternative or in addition, it can also be realized that the contact protection element has a columnar structure and the temperature sensor is arranged inside the contact protection element. In this case, the temperature sensor is particularly well protected from mechanical stresses during the insertion process.

[0016] According to a further advantageous embodiment of the invention, the conductive contact element comprises a cylindrical body and a spring element (also called a spring contact) for making spring-like contact with the mating conductive contact element. As a result, when connecting a plug-in connector and a mating plug-in connector together, the necessary contact pressure between the electrical contact elements with each other and on the temperature sensor can be generated in a simple manner.

[0017] In particular, the spring element can essentially have a ring-like shape and may have a number of flexible tongues for clamping on both sides, and these flexible tongues are bent radially inwards such that their centers contact the mating conductive contact element. This ensures a uniform and reliable contact pressure that guarantees secure electrical and mechanical contact even in the presence of vibrations and a wide temperature range.

[0018] In particular, for the protection of the connecting wires, it can be achieved that the electrical connecting wires of at least one temperature sensor are routed through the contact protection element.

[0019] According to an advantageous further development of the invention, the contact protection element is implemented as an electrically insulating, electrically insulating synthetic part that is press-fitted into the conductive contact element. This enables the temperature sensor to be directly overmolded, for example, such that its housing simultaneously forms the contact protection element. This reduces manufacturing costs and ensures a compact structure.

[0020] The invention further relates to a plug-in connector having a plug-in connector element according to the invention and an associated mating plug-in connector element.

[0021] According to an exemplary embodiment, the mating plug-in connector element has a mating conductive contact element with a cylindrical contact area, and in the plugged-in state of the plug-in connector, the contact area of the mating conductive contact element grips around the contact protection element. Such a concentric structure has the advantages that the structure is particularly compact and the force distribution when the connector element is plugged in is symmetric.

[0022] In order to achieve particularly good heat transfer and thus a short response time, it can be achieved that at least one temperature sensor is pressed onto the mating conductive contact element in the plugged-in state of the plug-in connector.

[0023] So that both connector elements meet the contact safety requirements of the HV component, the mating plug-in connector element further has a second housing and a contact protection cover material, and the contact protection cover material is arranged between the second housing and the contact protection cover material to prevent an object having a diameter exceeding a specified value from reaching the mating conductive contact element. For example, the contact protection cover material is essentially formed by a ring-shaped electrical insulating synthetic component, and this synthetic component is arranged on the front end region of the mating conductive contact element. Such a synthetic component can be manufactured cost-effectively and can be fastened or injection-molded onto a metallic contact element.

[0024] The advantageous characteristics of the plug-in connector of the present invention are particularly effective when the plug-in connector is implemented as a high-voltage plug-in connector for an electric vehicle.

[0025] To better understand the present invention, the present invention will be described in more detail by the embodiments shown in the following figures. Here, the same reference numerals and the same component names are given to the same parts. Furthermore, some features or combinations of features from the various embodiments shown and described may represent separate, independent, innovative, or novel solutions.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

[0027] Hereinafter, with reference to the drawings, and in particular with reference to the perspective view of FIG. 1 first, the present invention will be explained in more detail. It should be noted that in all the drawings, the size relationships, and in particular the layer thickness relationships, are not necessarily reproduced to an exact scale.

[0028] FIG. 1 shows, in the form of a schematic perspective view, a contact protection element 116 that can be found in a high voltage (HV) circular plug (e.g., with a diameter of 12 mm). The geometries of other plug connectors for temperature detection according to the principles of the present invention can of course be designed similarly.

[0029] According to one aspect of the present invention, the contact protection element 116 has an electrically insulating body 118 which, in the assembled state, has a columnar and elongated shape. For example, the body 118 can be made of a synthetic material.

[0030] According to the present invention, a temperature sensor 112 is embedded in the body 118 of the contact protection element 116. The temperature sensor 112 can represent, for example, an NTC thermistor, a thermoelement, a resistance temperature sensor (e.g., Pt), or any other suitable temperature sensor.

[0031] NTC stands for "negative temperature coefficient". An NTC thermistor is a temperature sensor that utilizes the resistance characteristics of a ceramic-metal composite for temperature measurement. NTC sensors offer many advantages for temperature measurement, such as small size, long-term stability, high accuracy, and precision.

[0032] A thermoelement sensor consists of two dissimilar metals that are connected to each other at one end. The temperature is measured at this junction point. The two metals generate a small voltage, which is measured and evaluated by a control system. The dissimilar metals are individually insulated, and a jacket is used to maintain a tight two-wire winding. Thermoelement sensors have the advantages of a wide operating temperature range, generally constant sensitivity over that range, and being available in a suitable miniaturized size.

[0033] A resistance sensor known as an RTD (resistance temperature detector) is a sensor used for temperature measurement, where the resistance changes proportionally to the temperature. RTD temperature sensors function even in locations with harsh or hazardous environments under various public approvals.

[0034] The temperature sensor 112 has a sensing region 120 for detecting the actual temperature and an electrical connection line 122 that connects the temperature sensor 112 to the necessary power supply and measurement signal acquisition (not shown in the figure).

[0035] According to an aspect of the present invention, the connection line 122 is routed through the body 118 and exits the body 118 at the base region 124. Thereby, the temperature sensor 112 and the connection line 122 are optimally protected from mechanical stress.

[0036] As will become apparent from the following Figure 3, the contact protection element 116 has a latch protruding edge 126 that circumferentially surrounds the base region 124, which engages with an associated latch groove 128 for fixing the contact protection element 116 within the plug-in connector element. The flange 130 serves to seal and mechanically support the contact protection element 116 in the assembled state.

[0037] It is advantageous to fabricate such a contact protection element 116 with the temperature sensor 112 attached as a separate component, for example by overmolding the temperature sensor 112, and to maintain it in a state ready for final assembly. This can greatly simplify the attachment of the temperature sensor into the plug-in connector.

[0038] Figure 2 shows a perspective view of the HV plug-in connector element 102 attached to the current rail 132. As is apparent from the overview of the cross-sectional view of Figure 3, the contact protection element 116 is disposed inside the conductive socket contact 134 such that an object larger than the diameter of a specified test probe cannot access the conductive part from the outside. The plug-in connector element 102 comprises an electrically insulating housing 136, which covers the entire circumferential direction of the socket contact 134 in the radial direction and the front side of the insertion region.

[0039] The socket contact 134 comprises a conductive contact body 138, by which an electrical connection to the current rail 132 is established. To make electrical contact with a mating plug-in connector (see FIGS. 5 and 6), the socket contact 134 comprises a spring contact 140. The spring contact 140 comprises a plurality of radially inwardly curved flexible tongues 142 clamped on both sides, by which contact pressure is exerted on the contact elements of the mating plug-in connector. The region curved inwardly of the flexible tongue 142 forms the actual electrical contact region 144 in the plugged-in state of the plug-in connector, where unwanted heat accumulation first occurs.

[0040] According to a first advantageous aspect of the invention, in order to quickly detect overheating, the temperature sensor 112 is arranged such that its sensing region 120 is located directly adjacent to the contact region 144.

[0041] FIGS. 4 to 6 illustrate how the elements 102 of the plug-in connector and the mating plug-in connector element 104 are brought together to form the plugged-in state of the plug-in connector 100.

[0042] According to the illustrated embodiment, the mating plug-in connector element 104 comprises a hollow cylindrical mating conductive contact element 146, which grips around the contact protection element 116 when mated in the direction of 148 and at the same time makes electrical contact with the contact protection element 116 from the outside through the spring contact 140.

[0043] For electrical insulation, the mating plug-in connector 104 has an electrically insulating second housing 152 and an electrically insulating contact protection cover material 154. The contact protection cover material 154 is formed to prevent an object having a diameter exceeding a specified value from reaching the mating conductive contact element 146 between the second housing and the contact protection cover material.

[0044] When the temperature sensor 112 projects slightly from the outer surface of the contact protection element 116 which is smooth otherwise, at least within the sensing region 120, the temperature sensor is pressed against the inner surface of the mating conductive contact element 146 in the inserted state. As a result, a particularly tight thermal contact is ensured, and the temperature sensor 112 can respond particularly quickly and reliably to overheating in the critical region 150 marked by the dotted line.

[0045] Figures 7 to 10 show how the temperature detection functionality of the plug-in connector 100 can be changed without otherwise changing it, using various modifications of the contact protection element 116.

[0046] Figure 7 shows again, for comparison, the configuration clarified with reference to Figures 1 to 6.

[0047] As shown in Figure 8, the temperature sensor can also be arranged in the base region 124 of the closer contact protection element 116 so as to be able to monitor the temperature in the vicinity of the current rail.

[0048] Furthermore, guiding the temperature sensor through the center of the contact protection element 116 can in this way achieve on the one hand symmetric temperature detection and on the other hand mechanically protect the temperature sensor.

[0049] Finally, each of the contact protection elements 116 shown, preferably those shown in Figure 8, can be used even without the temperature sensor 112 simply. This modification is shown in Figure 10.

[0050] All the modifications shown in Figures 7 to 9 can also be combined with each other by using two or more temperature sensors 112, or a sensor having two or more sensing regions 120.

[0051] Figure 11 shows again in perspective view the plug-in connector 100 of the present invention in the inserted state.

[0052] FIG. 12 shows the contact protection functionality of the plug-in connector element 102. As shown, the test probe 114 passes through the free space between the contact protection element 116 and the housing 136 and cannot touch the conductive part, i.e., the socket contact 134.

[0053] Similarly, as shown in FIG. 13, the interaction between the second housing 152 and the contact protection cover material 154 prevents the test probe 114 (and for this reason, all objects having a diameter larger than the test probe) from touching the mating conductive contact element 146.

[0054] In summary, according to an exemplary aspect of the present invention, a new configuration of contact components, for example using a 12 mm circular contact having a finger protection part, allows the temperature sensor to be placed neutrally and flexibly with respect to the installation space even in the immediate vicinity of the hot spot. The sensor is placed at an optimal position with respect to the contact arrangement within the contact protection element. Depending on the mounting position, the required contact pressure of the sensor against the measurement surface is generated either by the insertion process or during the assembly of the contact protection part. Secure installation and routing of the connection wires of the sensor into the contact protection element are also possible. Using this solution, the temperature measurement of the HV plug-in connector becomes more accurate and more flexible.

[0055] Although the above description always describes circular contacts as examples, it should be further noted that other contact cross-sections as well as multiple contacts can of course be designed similarly according to the principles of the present invention.

Description of the reference numerals

[0056] 100, 200 Plug-in connector 102, 202 Plug-in connector element 104, 204 Mating plug-in connector element 206 Blade contact 108, 208 Contact area 110, 210 Spring contact elements 112, 212A, 212B Temperature sensors 114, 214 Test probes 116 Contact protection element 118 Body of the contact protection element 120 Sensing area 122 Connection wire 124 Base area 126 Latch protruding edge 128 Latch groove 130 Flange 132 Current rail 134 Socket contact, contact element 136 (First) housing 138 Contact body 140 Spring contact 142 Flexible tongue 144 Contact area 146 Opposite contact element 148 Insertion direction 150 Critical area 152 Opposite plug-in connector housing, second housing 154 Contact protection cover material

Claims

1. A plug-in connector element (102) for detachably making electrical contact with a mating plug-in connector element (104), wherein the plug-in connector element (102) comprises: - at least one conductive contact element (134); - a housing (136); - a contact protection element (116) arranged between the housing (136) and the contact protection element (116) to prevent an object having a diameter exceeding a specified value from reaching the conductive contact element (134); - at least one temperature sensor (112) at least partially received within the contact protection element (116) and operable to measure the temperature of the conductive contact element (134); the housing (136) has an essentially cylindrical inner surface in which the conductive contact element (134) is arranged, and the conductive contact element (134) at least partially surrounds the contact protection element (116); the contact protection element (116) has an electrically insulating body (118) having an elongated shape; the distance between the free end of the body (118) of the contact protection element (116) and the inner wall of the free end of the housing (136) is set to be equal to or less than the specified value, thereby preventing the object from reaching the conductive contact element (134); the at least one temperature sensor (112) is arranged to detect the temperature of the conductive contact element (134) in a contact region (144) where the conductive contact element (134) can make electrical contact through a mating conductive contact element (146) of the mating plug-in connector element (104); a plug-in connector element (102).

2. The body (118) of the contact protection element (116) is cylindrical, a plug-in connector element according to Claim 1.

3. The free end of the body (118) of the contact protection element (116) extends beyond the free end of the housing (136), a plug-in connector element according to Claim 1.

4. The contact protection element (116) has a columnar structure, and the temperature sensor (112) is arranged on the outer wall of the contact protection element (116). The plug-in connector element according to any one of claims 1 to 3.

5. The contact protection element (116) has a columnar structure, and the temperature sensor (112) is disposed inside the contact protection element (116). The plug-in connector element according to any one of claims 1 to 4.

6. The conductive contact element (134) includes a cylindrical body (138) and a spring contact (140) for spring-loaded contact with the mating conductive contact element (146). The plug-in connector element according to any one of claims 1 to 5.

7. The spring contact (140) has a shape essentially like a ring and includes a number of flexible tongues (142) clamped on both sides, and the flexible tongues (142) are bent radially inward such that their centers contact the mating conductive contact element (146). The plug-in connector element according to claim 6.

8. The electrical connection wire (122) of the at least one temperature sensor (112) is routed through the contact protection element (116). The plug-in connector element according to any one of claims 1 to 7.

9. The contact protection element (116) is press-fitted into the conductive contact element (134) and is mounted as an electrically insulating composite part. The plug-in connector element according to any one of claims 1 to 8.

10. - A plug-in connector element (102) according to any one of claims 1 to 9, - And a related mating plug-in connector element (104). A plug-in connector.

11. The mating plug-in connector element (104) has a mating conductive contact element (146) having a cylindrical contact area. In the inserted state of the plug-in connector (100), the contact area of the mating conductive contact element (146) surrounds the contact protection element (116). The plug-in connector according to claim 10.

12. The at least one temperature sensor (112) is pressed onto the mating conductive contact element (146) in the inserted state of the plug-in connector (100). The plug-in connector according to claim 10 or 11.

13. The mating plug connector element (104) further comprises a second housing (152) and a contact protection cover member (154), the contact protection cover member (154) is arranged between the second housing (152) and the contact protection cover member (154) so as to prevent an object having a diameter exceeding a specified value from reaching the mating conductive contact element (146). The plug connector according to any one of claims 10 to 12.

14. The contact protection cover member (154) is essentially formed by a ring-shaped electrically insulating synthetic component, the synthetic component is arranged on the front end region of the mating conductive contact element (146). The plug connector according to claim 13, which depends on claim 11.

15. The plug connector (100) is implemented as a high-voltage plug connector for an electric vehicle. The plug connector according to any one of claims 10 to 14.

Images