Touch-protected contact part

Abstract

A contact part (1) protected against contact with a mating contact part (52) for connecting battery modules, the contact part (1) being designed to be connected to a mating contact part (52) in a plug-in direction (10), the contact part (1) comprising a contact element (2) made of a first material, a connecting element (14) penetrating the contact element (2) and electrically conductively connected to the contact element (2), and a contact housing (24) accommodating the contact element (2) and the connecting element (14); the connecting element (14) being held relative to the contact housing (24) in a plug-in position (30) in which the connecting element (14) protrudes from the contact element (2) in the plug-in direction (10), and the part (18) of the connecting element (14) penetrating the contact element (2) and protruding from the contact element (2) being made of a second material whose electrical resistance is greater than the electrical resistance of the first material.

Description

[0001] The present invention relates to a touch-protected contact part for the electrical connection of battery modules, particularly in electric vehicles, wherein the contact part is designed to be connected to a mating contact part. The invention further relates to a contact assembly comprising such a contact part and a mating contact part.

[0002] In an electric vehicle, the battery is the primary source of propulsion energy. A battery is typically made up of several battery modules that must be electrically connected to one another. The battery must also be connected to the electric vehicle's loads. The requirements for such connections are high. They must be robustly constructed to withstand high currents as well as vibrations and temperature influences. Furthermore, these connections must be touch-safe to ensure that people are not endangered by the high voltages and currents. Finally, precautions must be taken to prevent damage to or malfunctions of the electric vehicle's components when making the connections, for example due to sparks or arcing.

[0003] The invention is based on the object of providing a module connector that meets these requirements.

[0004] The present invention solves this problem on the one hand by means of a contact-protected contact part for the electrical connection of battery modules, wherein the contact part is designed to be connected to a mating contact part in a plug-in direction, wherein the contact part has a contact element made of a first material, a connecting element penetrating the contact element and electrically conductively connected to the contact element, and a contact housing accommodating the contact element and the connecting element, wherein the connecting element is held relative to the contact housing in a plug-in position in which the connecting element protrudes from the contact element in the plug-in direction, and the part of the connecting element penetrating the contact element and protruding from the contact element is made of a second material whose electrical resistance is greater than the electrical resistance of the first material.

[0005] The object is also achieved by a contact assembly with the contact-protected contact part described above and with a counter-contact part which has a counter-contact designed to be brought into electrical contact with the contact element, a counter-connecting element designed to be complementary to the connecting element for connecting the contact part and the counter-contact part, which is electrically conductively connected to the counter-contact, and a counter-contact housing in which the contact element and the counter-connecting element are accommodated.

[0006] These solutions allow for increased safety in high-current or high-voltage connections, ease of assembly, and the elimination of an additional pre-charging circuit, which would require more components and increase complexity. Due to its higher electrical resistance, the connecting element forms a pre-charging resistor that reduces or even prevents arcing faults.

[0007] The higher-resistance material of the connecting element reduces voltage peaks during connection. At the same time, the protrusion of the connecting element from the contact element ensures that one end of an arc is on the connecting element.

[0008] The invention can be further improved by the following embodiments, each of which is advantageous in itself and can be combined with one another as desired.

[0009] The first and second materials are preferably first class conductors and contain, for example, metals which have good conductivity.

[0010] The first material can, in particular, contain copper and / or aluminum, or consist of copper and / or aluminum. Both materials have high conductivity, are durable, easily formable, versatile, and inexpensive.

[0011] The second material may contain or consist of steel. Steel components have a higher melting point and higher electrical resistance, resulting in lower currents and less material removal in the event of a spark.

[0012] The connecting element can have a screw or be designed as a screw that has a threaded section and a pre-contact pin that adjoins the threaded section in the plug-in direction. The pre-contact pin ensures that the connecting element is the first to make contact with the mating contact part and that the thread is not destroyed by an arc. The diameter of the pre-contact pin should be smaller than the core diameter of the threaded section. The length of the pre-contact pin in the longitudinal direction can range from approximately one-third of its diameter to approximately its diameter or more. The longitudinal axis of the screw and in particular also of the pre-contact pin preferably runs parallel to the plug-in direction.

[0013] The screw is rotatably mounted by the contact housing and can advantageously be driven or screwed in from outside the contact part. In particular, it has a head with a screw drive, which should be designed to be touch-protected. Furthermore, the screw can have a flange that follows the head in the insertion direction and has a larger diameter than the diameter of the head.

[0014] In an alternative embodiment, the connecting element can have a threaded bushing with an internal thread or be designed as a threaded bushing. The mating connecting element can then have a screw.

[0015] In an advantageous embodiment, the contact element can have a busbar or be designed as a busbar. Alternatively or cumulatively, the contact element can have a contact socket or be designed as a contact socket. A combination of busbar and contact socket is also possible. The different options have the advantage that the contact element can be adapted to different installation space requirements depending on the application.

[0016] An advantageous embodiment of the invention can comprise a contact guard made of an electrically insulating material that surrounds the connecting element at its end opposite the plugging direction. If the connecting element is designed as a screw, the contact guard can surround a screw head of the connecting element, enabling safe manual assembly.

[0017] In one embodiment, the connecting element can be longer than the contact element and protrude from the contact element. Alternatively, the connecting element can be shorter than the contact element and not protrude from the contact element. Accordingly, the mating connecting element can be configured to complement the contact and be longer than the mating contact, for example, if the connecting element is configured to be shorter.

[0018] An advantageous embodiment of the contact part can have a spring element by which the connecting element is resiliently held in the plug-in position along the plug-in direction.

[0019] The spring element can be supported, in particular axially, between the contact housing and the connecting element. The spring element can be a separate part and rest on the end of the connecting element facing opposite the plugging direction. The spring element can rest on the head, in particular on the flange, of the connecting element. The spring element can thus generate an axial spring force that presses the connecting element into the desired position. The spring element can be a disc spring. The spring element can also be a helical spring, such as a compression spring. The use of springs is cost-effective and enables simple production of the contact part.

[0020] According to a further embodiment, the spring element can be formed monolithically from the contact housing. The spring element can be designed, for example, as a contact tongue that engages the connecting element in a radially resilient manner transversely to and / or in the plugging direction. The spring element can rest against the connecting element via inclined surfaces. The inclined surfaces can convert the radial spring force of the spring element into the axial direction. Such a monolithic spring element is easier to manufacture and simplifies assembly.

[0021] A design with multiple spring elements, each in one of the above configurations, is also possible. The spring elements can, in particular, be of identical design.

[0022] In an alternative or cumulative embodiment, the connecting element can be held frictionally in the contact housing, which reduces the number of components and enables easy handling.

[0023] Furthermore, the connecting element can be overmoulded by the housing in order to save assembly steps.

[0024] An advantageous embodiment of the contact assembly provides that the contact element and the mating connection element are accommodated in the mating contact housing in a touch-protected manner in order to meet the safety requirements.

[0025] Depending on the design of the connecting element, the mating connection element can, for example, be a threaded bushing if the connecting element is a screw. The threaded bushing can protrude from the mating contact part toward the connecting element, counter to the plugging direction, and protrude above the surface of the mating contact. Alternatively or cumulatively, the mating contact can have a flat surface and be formed, for example, by the busbar itself.

[0026] The mating contact can be made of the first material. The mating connecting element can be made of the second material. Thus, the mating contact and contact element can form a main contact pair made of the same material, and the connecting element and the mating connecting element can form a pre-contact pair, wherein the pre-contact pair can be electrically connected before the main contact during the plugging movement of the contact part and the mating contact part.

[0027] The contact part and the mating contact part can have housing sections that can be plugged into one another, through which the contact part and the mating contact part are guided along the plugging direction when plugged together. In particular, the housing sections can be designed such that the contact part and the mating contact part are positively guided when plugged together. With this design, movement transverse to the plugging direction can be blocked by the housing sections.

[0028] Furthermore, the contact part and the mating contact part can be designed to be plugged together in a plugging movement extending along the plugging direction, in particular the contact part and the mating contact part can be designed to be plugged together parallel to the plugging direction.

[0029] Throughout the mating movement until the contact element and mating contact make contact, the distance between the connecting element and the mating connecting element can always be smaller than the distance between the contact element and the mating contact. The distance between the pre-contact pin and the mating connecting element can always be smaller than the distance between the contact socket and the mating contact to ensure initial contact through the pre-contact pair.

[0030] Along the plugging movement, an electrical contact between the connecting element and the mating connecting element can occur before an electrical contact between the contact element and the mating contact.

[0031] The invention is described below by way of example with reference to the drawings using an exemplary embodiment. In the drawings, the same reference numerals are used throughout for elements that correspond to one another in terms of function and / or structure.

[0032] According to the above description, a feature of the exemplary embodiment may be omitted if the technical effect associated with that feature is not important for a particular application. Conversely, a feature not yet present in the exemplary embodiment may also be added to the exemplary embodiment in accordance with the above description if the technical effect of the feature to be added is important for a particular application.

[0033] They show: Fig. 1 a representation of the touch-protected contact part; Fig. 2 a sectional view of the touch-protected contact part; Fig. 3 a representation of the contact assembly with the touch-protected contact part and the mating contact part; Fig. 4 a sectional view of the first contact between contact part and counter contact part; and Fig. 5 a representation of the contact assembly with full contact.

[0034] In the Fig. 1 and Fig. 2 shows an embodiment of the touch-protected contact part 1.

[0035] Fig. 1 shows the touch-protected contact part 1, which has a contact element 2. In this example, the contact element 2 is formed directly by a busbar 4, in particular one end of the busbar 4. The contact element 2 can also be designed as a combination of busbar 4 and contact socket 6. The contact socket 6 can be omitted if the busbar 4 itself forms the contact element 2. The busbar 4 can be designed as an elongated plate and point with a wide longitudinal surface 8 in a plug-in direction 10, in which the contact part 1 is connected to a mating contact element (not shown). A connecting element 14 is inserted through an opening 12 of the contact element 2 and protrudes from the contact element 2 in the plug-in direction 10.

[0036] In an advantageous embodiment, the connecting element 14 can be designed as a screw 15 with a threaded portion 16. A pre-contact pin 18 can extend from the threaded portion 16 of the connecting element 14 in the plug-in direction 10. The diameter 20 of the pre-contact pin 18 can be smaller than the core diameter 22 of the threaded portion 16. The length of the pre-contact pin 18 in the plug-in direction 10 can be between approximately one-third of its diameter and approximately its diameter or more.

[0037] The contact element 2 and the connecting element 14 are surrounded by a contact housing 24, at least in sections, which protects against contact. The contact housing 24 can be monolithic. Likewise, the contact housing 24 can consist of several parts. The contact housing 24 has a through-opening 26 through which the connecting element 14 is inserted and through which the connecting element 14 protrudes from the contact housing 24 in the insertion direction 10. The through-opening 26 of the contact housing 24 and the opening 12 of the contact element 2 can be aligned coaxially with one another or can be designed to overlap at least partially, so that the connecting element can be guided through both openings 26, 12.

[0038] The contact housing 24 may further comprise a spring element 28 that holds the connecting element 14 in a plug-in position 30, in which it protrudes from the contact socket 6 in the plug-in direction. This should make it possible for the connecting element 14 to contact the mating contact part earlier than the contact element 2.

[0039] The spring element 28 generates, in particular, a spring force 32 to maintain the plugged-in position 30. The spring element 28 can be configured as a compression spring, for example, as a helical spring or as a disc spring. In a further advantageous embodiment, the spring element 28 can be part of the contact housing 24 and, in particular, can be formed monolithically therefrom. In such a case, the spring element 28 can be configured as a resilient contact tongue or clamping lug. Instead of a spring element 28, the connecting element 14 can also be held in the contact housing 24 by frictional engagement.

[0040] In the Fig. In the embodiment shown in Figure 1, the touch-protected contact part 1 has a touch guard 34, which is mounted or molded onto the connecting element 14 at its end opposite the plug-in direction and has a screw drive 36 for manual assembly. The touch guard 34 can be located on the non-contacting side 38 of the contact part 1, i.e., at the end 40 of the connecting element 14 opposite the plug-in direction 10.

[0041] Fig. 2 shows a sectional view of the touch-protected contact part 1, in which an embodiment of the connecting element 14 is shown as a screw with a flange 41 and / or a screw head 42 on the non-contacting end 40 of the connecting element 14, wherein the screw head 42 rests on the surface 44 of the busbar 4 of the contact element 2 on the non-contacting side 38. The touch protection 34 surrounds the screw head 42 and is pressed into the plug-in position 30 by the spring element 28, which is located between the contact housing 24 and the touch protection 34 or the connecting element 14. The spring element rests on the flange 41, the diameter of which is larger than the diameter of the screw head 42 and which directly follows the screw head 42 in the plug-in direction.

[0042] The contact element 2 is in Fig. 2 as a connection of busbar 4 and contact socket 6, wherein the connecting element 14 is inserted in the plugging direction 10 first through the busbar 4 and then through the contact socket 6 and protrudes from the contact socket 6. All three elements are electrically connected to one another in the touch-protected contact part.

[0043] The connecting element 14 is made of a different material than the contact element 2. Thus, the connecting element 14 can be made of steel, and the contact element 2 can be made of copper. In this advantageous embodiment, the contact housing 24 is split in two in the plug-in direction, and one half 46 holds the contact socket 6 on the busbar 4. The spring element 28 can be located in the other half 48.

[0044] In the Fig. 3 to 5, the contact assembly 50 is shown with the touch-protected contact part 1 and the counter contact part 52.

[0045] Fig. 3 shows the touch-protected contact assembly 50 before contacting.

[0046] The mating contact part 52 has a mating connection element 54 and a mating contact 56. The mating connection element 54 is designed to complement the connection element 14. The mating connection element 54 can be designed as a threaded bushing 55 with an internal thread 58, wherein the threaded portion 16 is configured such that the threaded portion 16 engages the internal thread 58 of the mating connection element 56 upon contact. The mating contact 56 can be a busbar 4. Likewise, the mating contact 56 can be a combination of busbar 4 and contact bushing 6.

[0047] The busbar 4 of the touch-protected contact part 1 and the busbar 4 of the mating contact part 52 can each face the other busbar 4 with a wide longitudinal surface 8. The busbars 4 can be aligned parallel to each other and spaced apart from each other before contacting.

[0048] In the mating contact part 52, the mating connection element 54 is passed through an opening 60 of the mating contact 56 and protrudes above the surface of the busbar 4 opposite to the plugging direction 10.

[0049] One embodiment provides a protective ring 62 made of non-conductive material, which is placed on the mating connection element 54 with the through-hole 64. The protective ring 62 can serve as a finger guard during assembly. The protective ring 62 can have a slightly larger diameter than the mating connection element 54.

[0050] Using the touch protection 34 of the touch-protected contact part 1, the connecting element 14 can be manually rotated around the axis of the plug-in direction 10. The mating connecting element 54 can be made of the same material as the connecting element 14. The mating connecting element 54 can be made of steel or a material containing steel. The mating contact 56 can be made of the same material as the contact element 2.

[0051] Fig. 4 shows the contact assembly 50 at the first contact during assembly. Fig. Figure 4 illustrates that the connecting element 14 with the pre-contact pin 18 first comes into contact with the mating connecting element 54 of the mating contact part 52, while the contact element 2 and the mating contact 56 are still spaced apart by a distance 57. The protective ring 62 can protect against possible sparks. The connecting element 14 and the mating connecting element 54 can thus form a pre-contact pair, while the contact element 2 and the mating contact 56 form a main contact pair.

[0052] In this embodiment, the mating connection element 54 is designed such that a flange 66 is formed on the non-contacting end 68 of the mating connection element 54 and rests against the surface of the busbar 4 on the non-contacting side 70 of the mating contact part.

[0053] After the initial contact of the connecting element 14 with the mating connecting element 54, the contact element 2 can now be connected to the mating contact 56 by screwing the connecting element 14 into the mating connecting element 54 by hand over the contact protection 34.

[0054] The contact housing 24 of the touch-protected contact part 1 and the mating contact housing 74 can be designed such that a housing section 72 of the contact housing 24 can be inserted into the mating contact housing 74 in sections and the housing section 72 thus has a smaller diameter than the mating contact housing 74. Alternatively, the mating contact housing 74 can have a smaller diameter in sections than the contact housing 24, so that the contact housing 24 can be inserted at least in sections over the mating contact housing 74.

[0055] In particular, the housing section 72 and the mating contact housing 74 can be designed such that the connection of the connecting element 14 with the mating connecting element 54 and the connection of the contact element 2 with the mating contact 56 is guided on the housing section 72 along the plugging direction 10.

[0056] Fig.5 shows the contact assembly 50 with complete contact between the connecting element 14 and the mating connecting element 54, as well as between the contact element 2 and the mating contact 56. An alternative embodiment provides that the connecting element 14 is shorter than the contact element 2 and does not protrude from the contact element 2, while the mating connecting element 54 is longer than the mating contact 56 and protrudes from the mating contact 56, thus ensuring initial contact between the pre-contact pair. A reversed embodiment is also conceivable. Alternatively, the connecting element 14 can be designed as a threaded bushing 55, and the mating connecting element 54 as a screw that is frictionally connected to the threaded bushing 55. Reference symbol 1 touch-protected contact part 02 Contact element 04 Busbar 06 Contact socket 08 Longitudinal surface of the busbar 10 Plug-in direction 12 Opening of the contact element 14 Fastener, screw 15 screw 16 threaded section 18 pre-contact pins 20 Diameter of the pre-contact pin 22 Core diameter of the threaded section 24 contact housings 26 Through opening of the contact housing 28 Spring element 30 Plug-in position of the connecting element 32 spring force 34 Contact protection 36 screw drive 38 non-contacting side of the contact part 40 non-contacting end of the connecting element 41 Flange 42 screw head 44 Surface of the busbar 46 Half of the contact housing with the contact socket 48 Half of the contact housing with the spring element 50 contact assembly 52 Counter contact part 54 Counter-connecting element 55 threaded bushing 56 Counter contact 57 Distance between main contact pair 58 internal thread 60 Opening of the counter contact 62 protective ring 64 Through hole of the protective ring 66 Flange of the counter-connecting element 70 non-contacting side of the mating contact part 72 Housing section 74 mating contact housing

Claims

[1] Touch-protected contact part (1) for the electrical connection of battery modules, wherein the contact part (1) is designed to be connected to a mating contact part (52) in a plugging direction (10), wherein the contact part (1) comprises a contact element (2) made of a first material, a connecting element (14) penetrating the contact element (2) and electrically connected to the contact element (2) and a contact housing (24) accommodating the contact element (2) and the connecting element (14); wherein the connecting element (14) is held in a plug-in position (30) relative to the contact housing (24), in which the connecting element (14) protrudes from the contact element (2) in the plug-in direction (10), and the part (18) of the connecting element (14) penetrating the contact element (2) and projecting from the contact element (2) is made of a second material whose electrical resistance is greater than the electrical resistance of the first material. [2] Touch-protected contact part (1) according to claim 1, wherein the first and second materials are first-class electrical conductors. [3] Touch-protected contact part (1) according to claim 2, wherein the first material contains copper and / or aluminum and the second material contains steel. [4] Touch-protected contact part (1) according to one of claims 1 to 3, wherein the connecting element (14) has a screw which has a threaded portion (16) and a pre-contact pin (18) adjoining the threaded portion (16) in the plug-in direction (10), and wherein the diameter (20) of the pre-contact pin (18) is smaller than the core diameter (22) of the threaded portion (16). [5] Touch-protected contact part (1) according to one of claims 1 to 4, wherein the contact part (1) has a spring element (28) by means of which the connecting element (14) is held resiliently along the plug-in direction (10) in the plug-in position (30). [6] Touch-protected contact part (1) according to claim 5, wherein the spring element (28) is supported between the contact housing (24) and the connecting element (14). [7] Touch-protected contact part (1) according to one of claims 1 to 6, wherein the contact element (2) has a busbar (4). [8] Touch-protected contact part (1) according to one of claims 1 to 7, wherein the contact element (2) has a contact socket (6). [9] Contact-protected contact part (1) according to one of claims 1 to 8, wherein the connecting element (14) has a contact protection (34) made of an electrically insulating material, which surrounds the connecting element (14) at its end (40) located opposite to the plugging direction (10). [10] Contact assembly (50) for connecting battery modules, with a touch-protected contact part (1) according to one of claims 1 to 9 and with a counter-contact part (52) which has a counter-contact (56) designed to be brought into electrical contact with the contact element (2), a counter-connection element (54) designed to be complementary to the connecting element (14) for connecting the contact part (1) and the counter-contact part (52), which is electrically conductively connected to the counter-contact (56) and a mating contact housing (74) in which the contact element (2) and the mating connection element (54) are accommodated. [11] Contact assembly (50) according to claim 10, wherein the mating contact (56) is made of the first material and the mating connecting element (54) is made of the second material. [12] Contact assembly (50) according to claim 10 or 11, wherein the mating connecting element (54) has a threaded bushing (55). [13] Contact assembly (50) according to one of claims 10 to 12, wherein the contact part (1) and the mating contact part (52) have housing sections (72) which can be plugged into one another and through which the contact part (1) and the mating contact part (52) are guided along the plugging direction (10) when plugged together. [14] Contact assembly (50) according to one of claims 10 to 13, wherein the contact part (1) and the counter-contact part (52) are designed to be plugged together in a plugging movement extending along the plugging direction (10) and wherein along the plug-in movement up to the contact between contact element (2) and counter-contact (56), the distance between the connecting element (14) and the counter-connecting element is always smaller than the distance (57) between contact element (2) and counter-contact (56). [15] Contact assembly (50) according to one of claims 10 to 14, wherein the contact part (1) and the counter-contact part (52) are designed to be plugged together in a plugging movement extending along the plugging direction (10) and along the plugging movement, an electrical contact between the connecting element (14) and the mating connecting element (54) occurs before an electrical contact between the contact element (2) and the mating contact (56).

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