DE102017129281A1 - Liquid cooled contact element - Google Patents

Abstract

The invention relates to a system comprising an electrical contact element (1) and a cable (2) connected thereto, via which cooling liquid can be fed to the contact element (1), wherein the hollow cylinder (6) has an inlet opening (13) at the end, in which the in Cable guided cooling liquid in the axial direction in the contact element (1) can be flowed in and wherein the connecting part (3) has at least one opening (15) through which the cooling liquid in the radial direction from the contact element (1) can be flowed out.

Description

The invention is based on a system comprising an electrical contact element and a cable connected thereto, via which cooling fluid can be fed to the contact element, according to the preamble of the independent claim 1.

Such contact elements are used in particular for the transmission of high currents and used for example in charging connectors.

In electric vehicles, a fast charging is necessary if this technology is to prevail over conventional vehicles with internal combustion engine. The vehicles with internal combustion engine can be filled up within a few minutes. Electric vehicles must be able to keep up here. During fast charging processes, particularly high currents must be used, which leads to a high level of heat in charging connectors. If a limit temperature is exceeded for the connectors arranged in the charging connectors, the charging process is slowed down or completely aborted. The critical limit temperature is currently around 90 ° Celsius.

State of the art

The DE 10 2010 050 562 B3 shows a charging connector for electric cars. The heating of the connector generated during the charging process is reduced by a spiral-shaped liquid line, which runs essentially in the grip area of the connector. Through the liquid line flows a cooling liquid in a closed cooling circuit.

In the described connector, only the connector is cooled. Heat can still build up in the contact elements and the electrical conductors connected to them during operation, which can lead to a loss of power of the connector and associated longer charging processes.

task

The object of the invention is to generate a powerful contact element, in particular for use in charging connectors.

The object is solved by the characterizing features of independent claim 1.

Advantageous embodiments of the invention are specified in the subclaims.

The system according to the invention consists of an electrical contact element and a cable connected thereto, via which cooling liquid can be fed to the contact element. In addition to the cooling liquid, the contact element can of course also be acted upon by an electrical conductor contained in the cable with a current.

The contact element has at its end an inlet opening, in which the guided in the cable cooling liquid can be flowed into the contact element in the axial direction. The axial direction corresponds in this case the insertion direction of the contact element. The contact element has at least one opening through which the cooling liquid can be flowed out of the contact element in the radial direction. The radial direction is aligned approximately perpendicular to the insertion direction in this case. The electrical contact element according to the invention is optimally suitable for use in charging connectors. Such charging connectors are used for example for charging electric cars.

The contact element has a contact part and a connection part. The connection part is designed such that it can be connected to an electrical conductor of a cable. The contact element is supplied with cooling liquid. In the connection part of the contact element cavities are present in which flow cooling liquid and thereby absorb heat and can dissipate. The connection part is for this purpose connectable to an inflow line for cooling liquid. The electrical conductor and the inflow line can be connected to the contact element.

Advantageously, the electrical contact element is designed at least in two parts. The connection part and the contact part are each formed by separate components. The separate components can be reversibly connected to each other.

The bipartite has the advantage that the contact part can be replaced after a certain number of mating cycles, while the connection part can continue to be used. A connector can be used very quickly by replacing the contact parts again. Another advantage of this design is that the connection part and the contact part can be formed of different materials. The materials can be chosen according to your needs. For example, the contact part may be provided with a particularly good conductive coating, for example with a silver or gold alloy. For the connection part such a coating is not necessary. Here this can be omitted accordingly.

In an advantageous embodiment of the invention, the connection part and the contact part can be screwed together. This makes it possible for a worn through various mating cycles contact part plug side of the Remove connector and replace it with a new contact part.

Preferably, the contact part of the contact element is designed as a so-called socket with preferably four or six lamellae. The connection part is essentially cylindrical and has a hollow cylinder protruding axially from it. In the connection part is at least one opening, but preferably two, three or four openings, introduced.

In an advantageous variant of the invention, the cavity of the opening or the cavities of the openings are connected to the cavity of the hollow cylinder. Coolant can flow into the hollow cylinder of the connection part and the cooling liquid can flow out through the opening or through the openings. The cooling liquid can act directly on the contact element here. The cooling effect occurs exactly where the heat is generated during operation. Therefore, the cooling of the contact element shown here is also particularly effective, especially when the contact element is used in a charging connector for electric vehicles. Such charging connectors do not require additional cooling.

The cable connected to the contact element according to the invention consists in cross section of a central coolant line. Individual conductors, here copper wires, are positioned around the coolant line. The copper wires are enclosed by a foil. The film can be liquid-tight. On this film are so-called buffer elements, which are ultimately enclosed by a fixed cable sheath. The buffer elements are also hollow, so that a cooling liquid can flow in the region between the film and the cable jacket.

The film does not have to be liquid-tight, but rather serves to bundle the conductors or copper and to facilitate sliding between copper and the outer buffer elements, especially when bending the entire cable. The coolant can therefore also flow next to the small buffer elements or cooling hoses. The special charm of the buffer elements or small cooling hoses is the shielding against the cable sheath and the effective, because very direct and large, heat absorption.

By this effective heat absorption can be used with relatively little circulation volume, which allows a small coolant pressure throughout the cooling system. A typical value is here eg: at 500 Ampere current are about 2 liters of coolant per minute circulated and measured at the contact element temperature is only 50 ° C.

Preferably, the hollow cylinder tapers at the end and has an inlet opening. Seen upwardly from the inlet opening, a continuous lamellar structure is applied to the hollow cylinder. The lamellar structure serves for a good conductive contact between a conductor and the contact element.

The inlet opening of the hollow cylinder is inserted into the central coolant line. The outer diameter of the outlet opening and the inner diameter of the central coolant line are matched to one another.

On the lamellar structure of the hollow cylinder, the individual conductors of the cable described above are laid. Using a crimping sleeve, the conductors are pressed onto the lamellar structure. The lamellar structure ensures a particularly good conductive connection of the conductors with the connection part.

The contact element has a sleeve which on one side at least partially covers the connection part. In the connection part, two circumferential grooves are introduced, in each of which a sealing ring is inserted. Due to the seals, the overlap area of sleeve and connection part is sealed media-tight. The other end of the sleeve runs on the cable sheath of the cable. The inner diameter of the sleeve and the outer diameter of the cable are matched. About a pinch of the sleeve, the overlap area of sleeve and cable can be sealed media-tight.

The cooling of the contact element according to the invention proceeds as follows: The cooling liquid flowing in the cable reaches the connection part of the contact element and enters into the inlet opening of the hollow cylinder of the contact element. The liquid is able to absorb heat energy. Via the opening or the openings in the connection part of the contact element, the cooling liquid again emerges from the connection part and is discharged again via the cable. The cooling process described here is a cyclic process. The contact element is permanently lapped with fresh coolant.

The inflow direction of the cooling liquid is aligned perpendicular to the outflow direction of the cooling liquid. The radially exiting and heat energy laxative cooling fluid is swirled by the rushing to the connection part covering sleeve. This effect helps to transport the heat energy particularly efficiently away from the contact element.

embodiment

• 1 eine perspektivische Schnittdarstellung eines Kontaktelements mit einem angeschlossenen Kabel,
• 2 eine perspektivische Explosionszeichnung des Kontaktelements mit einer Hülse auf dem Anschlussteil,
• 3 eine perspektivische Darstellung eines Kontaktteils des Kontaktelements,
• 4 eine perspektivische Darstellung eines Anschlussteils des Kontaktelements,
• 5 eine perspektivische Darstellung einer Crimphülse,
• 6 eine perspektivische Darstellung eines Kabels mit einer integrierten Kühlflüssigkeitsleitung,
• 7 eine perspektivische Explosionszeichnung des Kontaktelements,
• 8 eine perspektivische Schnittdarstellung eines Steckverbinders mit integriertem Kontaktelement,
• 9 eine perspektivische Darstellung des Kontaktelements mit angeschlossenem Kabel und einer zweiteiligen Crimphülse und
• 10 eine Schnittdarstellung des Anschlussteils.

An embodiment of the invention is illustrated in the drawings and will be explained in more detail below. Show it:

• 1 a perspective sectional view of a contact element with a cable connected,
• 2 an exploded perspective view of the contact element with a sleeve on the connector,
• 3 a perspective view of a contact part of the contact element,
• 4 a perspective view of a connection part of the contact element,
• 5 a perspective view of a crimp sleeve,
• 6 a perspective view of a cable with an integrated coolant line,
• 7 an exploded perspective view of the contact element,
• 8th a perspective sectional view of a connector with integrated contact element,
• 9 a perspective view of the contact element with attached cable and a two-part crimp sleeve and
• 10 a sectional view of the connection part.

The figures contain partially simplified, schematic representations. In part, identical reference numerals are used for the same but possibly not identical elements. Different views of the same elements could be scaled differently.

The 1 shows a contact element 1 which is connected to a cable 2 is electrically connected to an integrated coolant line. The contact element 1 consists of a connection part 3 and a contact part 4 , The connection part 3 contains an axial bore 25 and the contact part 4 contains an axial through hole 26 , Both the hole 25 as well as the through hole 26 each contain an internal thread 5 and can be reversibly connected to each other via a screw (not shown). At the contact part 4 is a knurling 27 formed, which is a twist between the connection part 3 and contact part 4 prevented. Is the contact part 4 worn out after many mating cycles, can be a fresh contact part 4 be put on without the cable 2 again to the contact element 1 to have to connect. The cable 2 can permanently on the connection part 3 remain.

The contact part 4 is called a so-called socket with a total of 6 blades 7 educated. The connection part 3 is designed substantially cylindrical. Axially projecting from the main body is a hollow cylinder 6 formed. The hollow cylinder 6 can also be considered as a hollow needle. The hollow cylinder 6 tapers towards the end and opens into an entrance opening 13 , Between entrance opening 13 and main body is on the hollow cylinder 6 a lamellar structure 14 applied. In the connection part 3 are openings 15 introduced, which gives access to a cavity 16 inside the connection part 3 form. There are several openings 15 rotationally symmetrical along the lateral surface of the connection part 3 intended. The openings 15 each have the same distance from each other. The cavity 16 is also related to the cavity, the hollow cylinder 6 forms.

That at the contact element 1 connected cables 2 consists in cross section of a central coolant line 8th , To the coolant line 8th around are individual leaders 9 , here copper wires, positioned. The copper wires are made of a foil 10 (for illustrative reasons only hinted) enclosed. On this slide 10 lie so-called buffer elements 11 on top of that, by a solid cable sheath 12 are enclosed. The buffer elements 11 are also hollow, so that in the area between the film 10 and cable sheath 12 a cooling liquid can flow. The cable 2 is about a sleeve 17 on the contact element 1 attached. The connection part 3 has two circumferential grooves 19 on, in each of which a sealing ring (not shown for illustrative reasons) is arranged. About the sealing rings is the sleeve 17 sealed media-tight.

The entrance opening 13 of the hollow cylinder 6 gets into the central coolant line 8th of the cable 2 inserted. The inner diameter of the coolant line 8th is on the outside diameter of the hollow cylinder 6 or the inlet opening 13 Voted. The geometry of the inlet opening 13 prevents slipping out of the hollow cylinder 6 from the coolant line 8th , On the lamellar structure 14 of the hollow cylinder 6 are the electrical conductors 9 of the cable 2 electrically conductive. About a crimp barrel 18 ( 5 ) become the leaders 9 on the hollow cylinder 6 attached. To the cable 2 towards covers the crimp barrel 18 a part of the film 10 , At the other end seals the crimp barrel 18 liquid-tight to the main body of the connection part 3 from. The ladder 9 are therefore sealed liquid-tight.

The connection part 3 has a cavity through which cooling fluid can flow 16 on. The volume of the cavity can be adjusted so that sufficient heat can be dissipated via the cooling liquid, but the connection part still has sufficient massiveness.

The coolant flows through the central fluid line 8th in the direction of the arrow 22 in the entrance opening 13 of the contact element 1 or of the connection part 3 on. The cavity 16 of the connection part 3 is traversed by the cooling liquid. The heat generated during operation is absorbed by the coolant and along the arrow 21 through the openings 15 through the sleeve 17 along the arrow 20 transported away on the cable sheath side again.

In a remote system, the cooling liquid can be cooled down again and in a cycle back to the inlet opening 13 be supplied. Test have shown that the temperature at the contact element 1 at a current of 500 amps and at room temperature only rises to 50 ° C. The corresponding standards allow here a temperature rise to a maximum of 90 ° C. It follows that the contact elements according to the invention have an even greater current carrying capacity and thus large reserves. As a result, the charging connectors can be used several times directly behind each other, which allows a high-frequency use in public cargo stations.

In 8th is an open housing of a connector 23 shown in which the contact element 1 installed and attached to a cable 2 connected. In general, the connector includes 23 at least two contact elements 1 and also two connected cables 2 that contain a cooling line. The connector 23 may include other non-cooled contact elements (not shown), for example for control signals, which are each connected to cables without cooling function. The two cables 2 and other cables are united in a flexible tube (not shown for illustrative purposes) which extends from the cable outlet 24 of the connector 23 going on.

The 9 shows an alternative embodiment of the contact element 1 with a connected, coolant-carrying cable 2 , Here is the crimp barrel 18 ' executed in two parts. In 9 is for illustrative reasons only part of the two-part crimp barrel 18 ' shown.

In 10 is a special way of crimping the crimp barrel 18 shown. The crimp barrel 18 is brought into a so-called hex-star crimp shape. As a result, a uniform and particularly gas-tight crimping is achieved. This type of crimp also has very low resistance values. The individual ladder 9 be under the crimp barrel 18 squeezed together and are in touching contact with each other. This forms a closed, conductive copper layer around the connection part 3 around. In the area of the buffer elements 11 can the coolant through the crimp barrel 18 to the contact element 1 or to its connection part 3 stream.

LIST OF REFERENCE NUMBERS

1

contact element

2

electric wire

3

connector

4

contact part

5

inner thread

6

hollow cylinder

7

lamella

8th

Central coolant line

9

ladder

10

Liquid-tight foil

11

buffer element

12

cable sheath

13

inlet opening

14

lamellar structure

15

openings

16

cavity

17

shell

18

crimp barrel

19

groove

20

arrow

21

arrow

22

arrow

23

Connectors

24

cable outlet

25

drilling

26

Through Hole

27

knurling

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102010050562 B3 [0004]

Claims (12)

System comprising an electrical contact element (1) and a cable (2) connected thereto, wherein the cable (2) has at least one electrical conductor, which is conductively connected to the contact element (1), characterized in that the contact element (1) via the cable cooling liquid can be fed, that the contact element (1) has an inlet opening (13), in which the guided in the cable cooling liquid in the axial direction in the contact element (1) can be flowed in and that the contact element (1) at least one opening (15 ), through which the cooling liquid in the radial direction from the contact element (1) can be flowed out. System according to the preceding claim, characterized in that the contact element (1) has a contact part (4) and a connection part (3), wherein the connection part (3) with an electrical conductor (9) of the cable (2) is connectable, that the electrical Contact element (1) is designed at least in two parts, and the connecting part (3) and the contact part (4) are each designed as separate components, which are reversibly connected to each other. System according to the preceding claim, characterized in that the connection part (3) has a cavity (16) through which the cooling liquid can flow. System according to one of the two preceding claims, characterized in that the connecting part (3) and the contact part (4) are screwed together. System according to one of the three preceding claims, characterized in that the contact part (4) is designed as a socket. System according to one of the four preceding claims, characterized in that the connecting part (3) is substantially cylindrical and has a hollow cylinder (6). System according to one of the preceding claims, characterized in that the at least one opening (15) opens up a cavity (16) which is connected to the cavity of the hollow cylinder (6). System according to one of the preceding claims, characterized in that the contact element (1) has a sleeve (17) which at least partially covers the connection part (3). System according to one of the preceding claims, characterized in that on the hollow cylinder (6) a lamellar structure (14) is applied. System according to one of the preceding claims, characterized in that the cable (2) consists in cross section of a central cooling liquid line (8) and around the cooling liquid line (8) positioned around electrical conductors (9). System according to the preceding claim, characterized in that the electrical conductors of a film (10) are enclosed and thereon buffer elements (11) are arranged, which are ultimately enclosed by a fixed cable sheath (12). System according to the preceding claim, characterized in that the buffer elements (11) are hollow.

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