Contact arrangement including cooling device for a plug-in connection, namely a charging plug

Abstract

The invention relates to a contact assembly for a plug-in connection, i.e. a charging plug, for transmitting electric power, which has at least one device for producing an electrically conductive connection and a device for at least one cooling purpose, i.e. for dissipating heat generated by transmitting electric power using the electrically conductive connection, wherein the electrically conductive device has at least one connection region for coupling to at least one cooling region boundary and at least one contact region, and the coupling is directly performed in an integral manner, so that the cooling effect is supported due to at least partially direct physical contact between the electrically conductive device and the coolant. The invention also relates to a plug-in connection, i.e. a charging plug, comprising at least one such contact assembly.

Description

Technical Field

[0001] The invention relates to a contact arrangement for a plug-in connection, a charging plug, for transmitting electric power, the contact arrangement having at least one device for producing an electrically conductive connection and at least one device for cooling purposes, for dissipating the heat generated by transmitting electric power via the electrically conductive connection. The invention also relates to a plug-in connection, a charging plug, having at least one such contact arrangement. Background Art

[0002] The contact generally has at least one electrically conductive contact portion for releasably, temporarily or pluggably connecting to a corresponding mating contact element, and a shaft portion adjacent to the contact portion for fastening the power line to the contact. Such a contact, plug contact, high-current contact can be used on a charging plug or charging socket, for example for charging an electrically driven vehicle. In this case, the cable is connected to the charging station on the one hand and supports a plug connector portion in the form of a charging plug on the other hand, which can be plugged into an associated mating plug connector portion in the form of a charging socket on the vehicle, so as to thus produce an electrical connection between the charging station and the vehicle.

[0003] The charging current can be transmitted essentially as direct current or alternating current, wherein in particular the charging current in the form of direct current and the high current range have a high current intensity, for example above 200 A or even above 300 A or even 350 A, and may cause heating of the cable and the high current contacts connected to the cable.

[0004] During the charging process of an electrical energy store, a battery, heat is generated due to the high power, current, transmitted. This heat is generated not only at the cable by which the charging plug is connected to, for example, a charging station, but also at the charging plug and in particular within the charging plug (for example at the high-current contacts) when the charging plug is plugged into a charging socket and power is transmitted, via which electrical contact is established with associated mating contacts on the electric vehicle (for example of the charging socket).

[0005] When a charging current flows through a contact, a plug contact, a high-current contact, such a high-current contact made of a conductive material (for example, a copper material) heats up, wherein the dimensions of the contact should be designed essentially according to the charging current to be transmitted, so that the contact has sufficient current-carrying capacity and the heating at the contact element is limited. The situation here is that the size of the contact needs to increase with increasing charging current to be transmitted. However, due to the associated space requirements, weight and costs, scaling the contact element size according to the increased charging current is limited. Therefore, it is necessary to transmit high charging currents by means of contacts with relatively small dimensions.

[0006] High charging currents are particularly important for the required electric mobility. Only in this way can the electric vehicle or its energy storage be "refueled" in a short time.

[0007] A solution to this problem that is basically known in the prior art is to passively or actively cool the contacts, the high-current contacts, in order thus to enable the transmission of power in structural elements with smaller dimensions while limiting the heating of the power transmission components.

[0008] DE 10 2016 204 895 A1 discloses an electrical contact system for a charging plug and / or a charging socket, and a charging plug for connecting to a corresponding connection device and for transmitting electrical energy. The object to be achieved is to provide a charging plug through which higher charging currents can be transmitted without the charging plug overheating.

[0009] As a solution, a power contact system for a charging plug and / or a charging socket is proposed, which has a power contact with a first connection area for galvanic connection to an electrical energy receiver and a second connection area for galvanic connection to a charging cable.

[0010] A cooling element is provided which is in direct contact with the second connection area of ​​the power contact, wherein the cooling element has a cooling fluid supply connection and a cooling fluid discharge connection, which are fluidically connected to the cooling fluid supply connection via a cooling fluid channel arranged in the cooling element. The cooling fluid supply connection and the cooling fluid discharge connection are arranged in a cooling element cover and are connected to the cooling element so that a flow can pass therethrough, the cooling element being designed in such a way that the cooling fluid is not in direct contact with the power contact.

[0011] US 2015 / 0217654 A1 of Tesla discloses a charging system for an electric vehicle, the charging system having a power source, a cable with a first end and a second end, wherein the first end is secured to the power source, wherein the cable includes a charging line and a cooling line, each of which extends from the first end to the second end; and the charging system has a connector secured to the second end of the cable, wherein the connector has a form factor corresponding to a charging station for an electric vehicle; wherein the cooling line is adapted to convey a fluid that cools the charging line, the line. Conveniently, the cooling line and the current-carrying charging line, the line are arranged as a wiring harness.

[0012] A charging cable with contacts, high-current contacts, known from DE 10 2010 007 975 B4, has a cooling circuit which comprises a supply line and a return line for a coolant, thereby enabling the coolant to flow back and forth in the charging cable. In this case, the cooling circuit of DE 10 2010 007 975 B4 serves to dissipate heat losses generated at the energy storage of the vehicle, but also to cool the cable itself. In order to achieve a cooling effect on the charging cable, the charging cable is arranged concentrically in the cooling circuit and a cooling medium flows around it.

[0013] An electrical connection body for a charging plug with a cooling device is disclosed in EP 3 043 421 A1. An electrical connection body for a charging plug and / or a charging socket is presented, which has a first connection area for galvanic connection to an electrical energy receiver and a second connection area for galvanic connection to an electrical energy source, and wherein the electrical connection body has a cooling fluid channel formed in the electrical connection body.

[0014] Known cooling solutions for plug connections, charging plugs, contacts, high-current contacts are disadvantageous or require improvement in many respects. The cooling medium volume flow is often insufficient to cope with the reduced cross-sections of the supply and discharge lines to and from the cooling element. The volume of the cooling element is also in many cases not sufficiently large.

[0015] Another problem with efficient cooling is the often inadequate heat transfer between areas with high temperatures and the cooling medium. This is often caused by too small a contact surface between the component to be cooled or the contact piece and the contact element. The components that carry the cooling medium and carry high currents are often separate, self-sufficient elements, which results in a reduced heat transfer between them.

[0016] Many available cooling devices are designed in such a way that only sections of the high current contacts are exposed to the cooling capacity. Typically, only the contact area with the mating plug is cooled, or the line is subjected to the cooling effect. The connection between the line and the contact is then usually cooled only when the conductive supply line is a braided structure.

[0017] Many cooling solutions offered for high-current contacts are also unconvincing in terms of safety. Available cooling devices offer no protection or emergency function in the event of a cooling failure, for example due to a failure of a cooling medium pump or interruption of the supply or discharge of the cooling medium. Summary of the invention

[0018] The object of the present invention is to further develop existing cooling solutions for contact arrangements, contact pieces, high-current contact pieces, such that the above-mentioned disadvantages of the prior art are at least partially reduced and the reliability of the cooling is improved.

[0019] The invention recognizes that in addition to cooling the contacts, high-current contacts to increase the current to be transmitted while maintaining the same line cross section, the direct connection of conductors and cooling hoses to the contact elements, high-current contacts is suitable for achieving a significant improvement in cooling. Due to the direct physical contact, the direct connection in an integral manner contributes both to the conduction of electrical energy and to a direct, improved heat transfer between the hot line components and the cooling medium.

[0020] Due to the arrangement of the contact elements, the high-current contacts, in the contact carrier, the connecting element and thus in the cooling element, an additional coolant safety reservoir can be created, which can serve as a buffer in the event of a failure, such as a coolant circulation, insufficient coolant volume flow or a coolant pump failure. In comparison with supply hoses and discharge hoses arranged parallel to the electrical conductors, the outer coolant hose contributes to achieving a larger cross-sectional surface, so that the coolant volume flow can be increased.

[0021] In terms of structure, the invention proposes that the current-carrying conductors, the lines, are located in the cooling hose. The conductors and the cooling hose are directly connected to the connecting element, the contact carrier. The connecting element, the contact carrier has at least one transverse hole through which the cooling medium can be supplied to the reservoir forming the cooling element and discharged therefrom.

[0022] If the invention is implemented by a contact arrangement in a plug connection in a charging system for an electric vehicle, two contact arrangements, high-current contacts, are usually arranged in the charging plug. In this variant, the invention provides two cooling medium hoses. As an example, the DC positive conductor is located in one hose and the DC negative conductor is located in one hose. One cooling medium hose serves as a supply line for the cooling medium and one as a return line. The two hoses can be fluidically connected via a cooling element.

[0023] The invention provides in particular that the cooling medium is formed as an electrical insulator and that a non-conductive liquid is therefore present. It is thus possible to connect the current-carrying components and the components carrying the cooling medium in an integral manner, so that the cooling effect is facilitated by at least partially direct physical contact between the conductive means and the cooling medium.

[0024] A series of advantages associated with the configuration according to the invention are:

[0025] - since the current-carrying conductor, the current supply line, is located in the cooling hose, this conductor can be crimped to the contact, the high-current contact, in a simple and reliable manner by means of a conventional crimping process, without the need for pigtails that would interfere with the connection,

[0026] - the supply cross section and the discharge cross section of the coolant conducting component, the coolant hose, are larger than the supply cross section and the discharge cross section of the individual hoses, so that a greater coolant volume flow can be achieved,

[0027] - High current contacts, the crimping area of ​​the contacts are all located in a non-conductive cooling liquid so that the insulation does not hinder heat transfer, as in the prior art,

[0028] - contributes to the flexibility and maneuverability of the entire current and cooling medium conduction arrangement as well as to its compactness,

[0029] Due to the structural design and dimensions of the coolant reservoir, heating of the device is limited both in normal load operation and in the event of an interruption (failure of the coolant volume flow). BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The invention is explained in more detail below with reference to exemplary embodiments in conjunction with the accompanying drawings, in which:

[0031] Figure 1a shows a perspective view of a contact arrangement with a contact piece and a cooling hose connected by a connecting region;

[0032] Figure 1b A contact arrangement is shown in a top view in a front view and in a sectional view CC in a bottom view, the contact arrangement having a connection region formed by at least one connecting element, a contact carrier with a contact receptacle;

[0033] Figure 2 A cross-sectional front view AA of a contact element with a cooling chamber boundary is shown in a top view, and a plan view of a contact element combination consisting of a first contact arrangement and a second contact arrangement, which at least partially have a common cooling chamber boundary, is shown in a bottom view;

[0034] Figure 3 A front view of a contact element with a cooling chamber boundary is shown in a top view, and a sectional plane view BB of a contact combination consisting of a first contact arrangement and a second contact arrangement which at least partially have a common cooling chamber boundary is shown in a bottom view. DETAILED DESCRIPTION

[0035] Figure 1aThe perspective view includes a contact arrangement with the contact region 10 and components of a cooling chamber boundary 40 which is realized by a cooling hose 41 , connected by the connecting region 30 and connected thereto.

[0036] Figure 1b A contact arrangement is shown in a top view in a front view and in a sectional view CC in a bottom view, which contact arrangement is formed by at least one connecting element 31 with a contact receptacle 32 in a front view.

[0037] The connection region 30 connects at least one contact device 11 to a hose receptacle 33, substantially via a connection element, a contact carrier 31 via a contact receptacle 32 in a manner that is both electrically conductive and carries a cooling medium. The receptacles 32, 33 of this exemplary embodiment are designed both flush and concentric with the central axis and are functionally supplemented by a receptacle 34 for the electrical conductor 20, which is likewise flush and concentric. Preferably, the connection element 31 is made of a material having electrically and thermally conductive properties.

[0038] In the exemplary embodiment shown, the contact receptacle 32 and the line receptacle 34 in the connecting element 31 are designed as holes, bores, blind holes with or without internal threads, which meet at the end faces and are respectively axially coupled and, in the case of being designed as blind holes, can have an angled tip of about 120° at the end faces due to a drill. Through holes with a constant or varying diameter can also be realized.

[0039] The area of ​​the contact receptacle 32 is preferably, but not necessarily, provided with an internal thread which is designed to be compatible with the adapter or the contact device 11 in such a way that the contact device 11 can be fixed in place by the connecting element, the contact carrier 31 or in it. The area of ​​the line receptacle 34 is constructed in such a way that the line 20 can be fixed in place. The connection can be made by a press fit, by a crimping process or by a clamping element in the connecting element 31. Since the connection properties of the crimping connection are particularly reliable, this is generally the preferred solution.

[0040] The end face of the connecting element 31 is designed as a hose receptacle 33 for connecting a cooling hose 41. In the simplest case of geometric configuration, the hose receptacle 33 is formed by a cylindrical part onto which the hose 41 can be pushed in the axial direction. The hose 41 can be fixed in place, for example, by a clip, a hose clamp or by a press fit. The hose receptacle 33 can optionally be supplemented by a hose stop 35 in the form of a shoulder in the push-in direction and / or an end face chamfer, an insertion ramp 36.

[0041] Figure 2A cross-sectional front view AA of a contact element is shown in top view, which has an outer cooling chamber boundary 40, which is substantially formed by at least one cooling hose 41 and at least one cooling housing 42. The outer cooling chamber boundary 40 forms the envelope, the outer boundary of at least one cooling element 50 with a connecting cooling region, a cooling reservoir 52, and at least one line cooling region 51.

[0042] A cooling housing adapter 43 may optionally be provided to couple the cooling housing 42 to the connecting element 31. In addition to the manufacturing-related advantages due to the simple geometry of the connecting element 31, the cooling reservoir 52 can be increased in volume and / or adapted to the respectively required cooling capacity without having to change the geometry of the contact arrangement. Thus, it is also facilitated to use similar parts for the contact arrangement when different cooling capacities are required, so that different variants of the contact arrangement are not required. Its manufacturing and costs as well as storage and parts logistics can thus be achieved in a cost-effective manner.

[0043] The outer cooling chamber boundary 40 can be sealed by means of a seal 44, with or without a cooling housing adapter 43. In particular, in the case of a rotationally symmetrical sealing collar, O-rings with a preferably circular cross section have proven to be effective, which are inserted into corresponding grooves with a groove depth that is smaller than the diameter of the ring.

[0044] The outer cooling chamber delimitation 40 cooperates functionally with the inner cooling chamber delimitation formed substantially by the line 20 and the connecting element 31. The geometrical design of the invention greatly improves the heat transfer of the current-carrying components 20, 31 within the outer cooling chamber delimitation 40 due to the direct physical contact with the cooling medium. It is important that the invention uses a cooling medium designed as an electrical insulator and therefore a non-conductive liquid.

[0045] Another measure to improve the cooling capacity is to creatively connect the line cooling area 51 and the connecting cooling area 52 fluidically. The fluid connection is achieved by at least one cooling connection, an opening 53, which connects the two areas 51, 52 in such a way that the cooling medium volume flow or the cooling medium exchange between the two areas is facilitated. The movement of the cooling medium between the line cooling area 51 and the connecting cooling area 52 can be carried out in the following ways: the cooling medium volume flow caused by the circulation caused by the temperature gradient in the medium or the components adjacent to the medium, and / or the supply and discharge in combination with the cooling medium pump. If two or more contact arrangements with cooling chamber boundaries 40 are used and the cooling medium chambers are connected to facilitate the volume flow, the line cooling area 51 can be used as a supply and return, discharge. Figure 2This variant is shown in a bottom view by way of example for two contact arrangements. The contact assembly shown consists of a first contact arrangement and a second contact arrangement, which at least partially have a common cooling chamber boundary 40. The cooling chamber boundary 40 is designed in such a way that a cooling medium volume flow between the contact arrangements is facilitated.

[0046] Figure 3 The front view of the contact element with a cooling chamber boundary 40 is shown in a top view, which is substantially formed by at least one cooling hose 41 and at least one cooling housing 42 and can be supplemented by a cooling housing adapter 43 .

[0047] exist Figure 3 In the bottom view of FIG. , a sectional plane view BB of a contact assembly is shown, which consists of a first contact arrangement and a second contact arrangement, which at least partially have a common cooling chamber boundary 40. The cooling chamber boundary 40 forms a cooling center area 52', so that the cooling medium volume flow between the contact arrangements is facilitated. Due to the annular connection or volume flow channel formed in this way, a cooling medium flow can be generated between the line cooling areas 51.

[0048] List of Reference Numerals

[0049] 10 Contact area, contact, high current contact

[0050] 11 Contact devices

[0051] 20 Lines and conductors

[0052] 30 Contact area (contact with the circuit)

[0053] 31. Connecting element, contact carrier

[0054] 32 Receptacles for contacts / high current contacts, contact receptacles

[0055] 33 Receiving area for hose, hose receptacle

[0056] 34 Receiving area for electrical conductors, line receptacles, crimp connections

[0057] 35 Hose stop

[0058] 36 Bevel cut, insert inclined piece

[0059] 40 (Outer) Cooling room boundary

[0060] 41 Hose, cooling hose

[0061] 42 Cooling housing

[0062] 43 Cooling housing adapter

[0063] 44 Sealing elements, seals, O-rings

[0064] 50 Cooling element, cooling medium volume

[0065] 51 Line cooling area

[0066] 52 Cooling reservoir, connected cooling area

[0067] 52' Cooling Center Area

[0068] 53 Cooling connections, openings, holes

Claims

1. A contact arrangement for a plug-in connector, a charging plug, for transmitting electric power, the contact arrangement having at least one device for producing an electrically conductive connection and at least one device for cooling purposes, wherein the device for cooling purposes is used to dissipate heat generated by transmitting electric power via the electrically conductive connection, characterized in that The electrically conductive device has at least one connection region (30) and at least one contact region (10) for connection to at least one cooling chamber boundary (40), wherein the connection is directly effected in an integral manner so that a cooling effect is promoted due to at least partially direct physical contact between the electrically conductive device and the cooling medium, wherein the cooling chamber boundary (40) is formed externally by at least one hose (41) and at least one cooling housing (42), wherein the at least one hose (41) surrounds the line (20) and can be connected to the connection region (30), and wherein the connection region (30) is formed by a connecting element (31) having at least one contact receptacle (32), wherein the connecting element (31) has at least one line receptacle (34), which line receptacle (34) comprises a crimping connection, and wherein the cooling housing (42) is connected to the connection region (30) via a cooling housing adapter (43).

2. The contact arrangement for a plug connection, a charging plug according to claim 1, characterized in that A contact device (11) can be received in the at least one contact region (10).

3. The contact arrangement for a plug-in connection, a charging plug according to claim 1, characterized in that The connecting element (31) has at least one hose receptacle (33).

4. The contact arrangement for a plug-in connection, a charging plug according to claim 3, characterized in that The hose receptacle (33) is supplemented by a chamfer (36) and / or a hose stop (35).

5. The contact arrangement for a plug-in connection, a charging plug according to claim 1, characterized in that The cooling housing (42) and the connecting region (30) form a connecting cooling region (52) in which a cooling medium can be received.

6. The contact arrangement for a plug connection, a charging plug according to claim 5, characterized in that The connection between the connecting cooling area (52) and the line cooling area (51) is carried out through at least one opening (53) in the connecting element (31), so that the flow of cooling medium between the connecting cooling area (52) and the line cooling area (51) is facilitated.

7. The contact arrangement for a plug-in connection, a charging plug according to claim 1, characterized in that The connection region between the cooling housing (42) and / or the cooling housing adapter (43) and / or the connecting region (30) is sealed by a sealing element (44).

8. A plug-in connection, a charging plug, for transmitting electrical energy, comprising at least one contact arrangement according to any one of claims 1 to 7.

9. The plug connector and charging plug for transmitting electrical energy according to claim 8, characterized in that: The plug connection, the charging plug, is formed by at least two contact arrangements, wherein at least one cooling core region (52') is formed by mutually adjacent cooling elements (50) having connected cooling regions (52).

10. The plug connector and charging plug for transmitting electrical energy according to claim 9, characterized in that: The cooling core region (52') facilitates the flow of cooling medium from the first circuit cooling region via the first connecting cooling region to the second connecting cooling region and the second circuit cooling region.

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