Plug-in connection unit and electric drive device

Abstract

Plug connection unit (1), comprising at least one first electrical contact element (10) designed as a projection (11) and at least one second electrical contact element (20) designed as a receptacle (21) for the projection (11), which are designed to realize an electrically conductive connection and a mechanical fastening of the projection (11) in the receptacle (21) at least along a first translational degree of freedom (40) of the projection along its insertion direction (41) into the receptacle (21) when the projection (11) is arranged in the receptacle (21), and wherein at least one of the two contact elements (10, 20) comprises a compensation device (50) for enabling relative movements (70) of sections of this contact element (10, 20) along the first translational degree of freedom (40),which has a lower tensile stiffness than the connection stiffness of the realized mechanical fastening of the projection (11) in the receptacle (21), wherein the compensation device (50) has at least one section of reduced flexural stiffness (51) which imparts the reduced tensile stiffness to the compensation device (50), and the section of reduced flexural stiffness (51) comprises a meandering bending element (52), characterized in that a pressure element (54) is arranged on at least one of two side edges (53) of the meandering bending element (52) opposite one another along the first translational degree of freedom (40), for bearing against the respective opposite side edge (53) in the event of a pressure load on the bending element (52) in the direction of the respective other contact element (10, 20), wherein the second electrical contact element (20),the at least one section of reduced flexural rigidity (51) and the pressure element (54) lie in one plane.,

Description

[0001] The invention relates to a plug connection unit and an electric drive device comprising at least one plug connection unit.

[0002] So-called electric axles are known from the prior art. These have an inverter and two electric rotating machines on an axle housing, and pumps associated with these electric rotating machines. Each electric rotating machine or pump has a plug-in connection unit to establish an electrical connection between the inverter and a respective pump, bypassing the respective electric rotating machine. Accordingly, the plug-in connection unit forms a so-called bypass.

[0003] Electrical contact elements of plug-in connection units can be designed as axially acting spring elements to compensate for manufacturing and / or joining tolerances. However, such spring elements have a disadvantage in that they can only partially permit or compensate for relative movement between the electrical contact elements, for example, due to temperature changes. Therefore, it cannot be ruled out that exceeding the maximum permissible relative movement could lead to an interruption of the electrical connection.

[0004] Publications DE 198 28 983 A1, DE 10 2016 112 759 A1, DE 692 17 582 T2, and DE 196 48 277 A1 disclose plug-in connection units with first and second electrical contact elements, wherein a compensation device is provided to enable relative movements. DE 10 2021 120 751 A1 discloses an electric drive device comprising at least one plug-in connection unit.

[0005] Based on this, the present invention is based on the object of providing a plug connection unit and an electric drive device equipped with the plug connection unit, which enable a permanent electrical connection of contacts in a simple, cost-effective and easy-to-assemble manner.

[0006] This object is achieved by the plug-in connection unit according to claim 1 and by the electric drive device according to claim 10. Advantageous embodiments of the plug-in connection unit are specified in subclaims 2-9.

[0007] The features of the claims can be combined in any technically reasonable manner, whereby the explanations from the following description as well as features from the figures can also be used to comprise additional embodiments of the invention.

[0008] The invention relates to a plug connection unit, comprising at least one first electrical contact element designed as a projection and at least one second electrical contact element designed as a receptacle for the projection, which are configured to realize an electrically conductive connection and a mechanical fastening of the projection in the receptacle at least along a first translational degree of freedom of the projection along its insertion direction into the receptacle when the projection is arranged in the receptacle. It is provided that at least one of the two contact elements comprises a compensation device for enabling relative movements of sections of this contact element along the first translational degree of freedom, which compensation device has a lower tensile stiffness than the connection stiffness of the realized mechanical fastening of the projection in the receptacle. The receptacle serves for inserting the projection.The compensation device has at least one section of reduced flexural rigidity, which imparts the reduced tensile rigidity to the compensation device. This section of reduced flexural rigidity causes an elastic or plastic bending in the section of reduced flexural rigidity upon introduction of a tensile load into the contact element equipped with the compensation device, before an elastic or plastic deformation in the mechanical fastening or a dissolution of the mechanical fastening between the receptacle and the projection occurs.

[0009] The section of reduced flexural rigidity comprises a meandering or S-shaped bending element, wherein the longitudinal direction of the formed meander shape runs essentially along the first translational degree of freedom or along the insertion direction.

[0010] A pressure element is arranged on at least one of two side edges of the meandering bending element, which are opposite each other along the first translational degree of freedom, for contact with the respective opposite side edge in the event of a compressive load on the bending element in the direction of the respective other contact element. Each pressure element can be considered a component of the side edge on which it is arranged.

[0011] The second electrical contact element, the at least one section of reduced flexural rigidity and the pressure element lie in one plane.

[0012] The connection stiffness mentioned is a stiffness against an unintentional relative movement between the projection and the receptacle, which carries the risk of breaking the mechanical connection and thus also interrupting the electrically conductive connection.

[0013] The connection stiffness can also be assumed to be tensile stiffness if the two mechanical contact elements are considered as a single ideal body. These stiffnesses are intended to characterize the resistance to elastic relative movement of elements of the compensation device or between the contact elements.

[0014] In an alternative embodiment, the stiffnesses mentioned characterize the resistance to a relative movement of elements of the compensation device or between the contact elements, which leads to a plastic deformation.

[0015] This means that the compensation device has a lower rigidity under tension and / or compression and is therefore more easily deformable along the first translational degree of freedom than the mechanical fastening of the projection in the receptacle, so that when a force is introduced into the plug connection unit along the first translational degree of freedom into the two contact elements, there is initially an elastic deformation of the compensation device before there is an elastic deformation in the mechanical fastening or in the receptacle and / or the projection.

[0016] The compensation device and the mechanical fastening can also be designed in such a way that when a force is introduced into the plug connection unit along the first translational degree of freedom into the two contact elements, a plastic deformation of the compensation device occurs before a plastic deformation occurs in the mechanical fastening or in the receptacle and / or the projection.

[0017] If necessary, the compensation device and the mechanical fastening can also be designed in such a way that when a force is introduced into the plug connection unit along the first translational degree of freedom into the two contact elements, a plastic deformation of the compensation device occurs before an elastic deformation occurs in the mechanical fastening or in the receptacle and / or the projection.

[0018] An elastic or plastic deformation in the mechanical fastening refers to the projection and / or to a contact element encompassed by the receptacle, which serves to engage the projection in order to form an electrical contact and a mechanical fixation there.

[0019] Furthermore, the compensation device and the mechanical fastening can be designed in such a way that when a force is introduced into the plug connection unit along the first translational degree of freedom into the two contact elements, an elastic deformation of the compensation device occurs before the mechanical fastening between the receptacle and the projection is released.

[0020] Alternatively, the compensation device and the mechanical fastening can be designed in such a way that when a force is introduced into the plug connection unit along the first translational degree of freedom into the two contact elements, a plastic deformation of the compensation device occurs before the mechanical fastening between the receptacle and the projection is released.

[0021] A dissolution of the mechanical fastening between the receptacle and the projection can also be understood as a sliding of the projection in the receptacle.

[0022] The plug connection unit is designed in such a way that a relative movement, which can occur, for example, due to different thermal expansion coefficients of the materials used, is compensated for by the compensation device before a movement occurs between the projection and the receptacle and, consequently, possibly leads to a dissolution of the electrically conductive connection.

[0023] An advantageous embodiment of the plug-in connection unit provides that the receptacle has at least one elastically acting contact element for contacting the projection. This contact element(s) are designed to bear against the projection, undergoing elastic deformation and applying a corresponding compressive force to the projection, thus establishing electrical contact and mechanical fixation.

[0024] The contact element can extend at an acute angle to the axis of the first translational degree of freedom. This embodiment or angle can occur particularly when the projection is not yet positioned in the receptacle, i.e., when the receptacle is undeformed.

[0025] By elastically deforming the contact element and / or a fastening area of ​​the contact element, the latter can be moved by inserting the projection into the receptacle in such a way that it rests against the projection under elastic prestress.

[0026] Accordingly, the plug-in connection unit allows for joining tolerance compensation by varying insertion depths of the projection in the receptacle.

[0027] In one embodiment, it is further provided that at least one of the contact elements is configured to bear against the projection with a surface contact. An alternative embodiment provides that at least one of the contact elements is configured to bear against the projection with an edge contact.

[0028] In the first alternative, the mechanical fastening is realized by abutting a contact surface of at least one contact element against the projection, without deformation of the projection. In the second alternative, the mechanical fastening is realized by abutting an edge between two contact surfaces of at least one contact element running at an angle to each other against the projection, with deformation of the projection due to the wedge effect created by the edge on the projection. One component of the edge's extension direction runs along the first translational degree of freedom.

[0029] In this embodiment, it is accordingly provided that the edge cuts into the projection, with a corresponding deformation or partial separation of the projection.

[0030] In the case where the bending element is not subjected to compression, the pressure element can be spaced apart from the respective opposite side edge and only come into contact with the opposite side edge when a certain pressure on the bending element is exceeded. A pressure element can be designed as a projection from the respective side edge.

[0031] The pressure element is designed to engage the opposite side when a compressive load is applied to the flexural element or the contact element equipped with it, thus ensuring the positive transmission of the compressive load without having to deform the flexible flexural element significantly. In this embodiment, the flexural element is thus equipped with high compressive stiffness, which, however, does not affect the still low flexural stiffness and thus tensile stiffness under tensile load. Furthermore, this results in minimal springback during assembly.

[0032] Accordingly, it is also possible for the pressure element to transfer the compressive forces acting upon insertion of the projection into the receptacle, allowing for less technological effort during insertion and eliminating the need to take precautions against excessive deformation of the flexural element. A so-called blind assembly can therefore be carried out in a simple manner.

[0033] The plug-in connection unit can comprise a plurality of the first electrical contact elements and the second electrical contact elements that can be plugged into one another. The connections of the first electrical contact elements and the second electrical contact elements can be arranged parallel to one another.

[0034] A further aspect of the present invention is an electric drive device having at least one described plug-in connection unit. The electric drive device can, for example, be a so-called electric axle, which has an inverter and two electric rotary machines on an axle housing, and has pumps associated with these electric rotary machines. A described plug-in connection unit can be present for each electric rotary machine or pump in order to establish an electrical connection between the inverter and a respective pump, bypassing a respective electric rotary machine. Accordingly, the plug-in connection unit can form a so-called bypass.

[0035] The invention described above will be explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, and it should be noted that the embodiments shown in the drawings are not limited to the dimensions shown. It is shown in Fig. 1: a plug connection unit according to the invention in sectional view, Fig. 2: a first enlarged partial area of ​​the plug connection unit in sectional view, Fig. 3: a second enlarged section of the plug connection unit in sectional view, and Fig. 4: a plug-in connection unit in assembled state.

[0036] First, the general structure of the plug connection unit 1 is explained using Fig. 1. The plug connection unit 1 comprises, as the first electrical contact element 10, a pin-shaped projection 11 that extends out of a housing 12 of the first electrical contact element.

[0037] Furthermore, the plug connection unit 1 comprises a second electrical contact element 20 in the form of a receptacle 21, which is arranged within a housing 26 of the second electrical contact element.

[0038] The receptacle 21 comprises two contact elements 22, which rest elastically on the projection 11 on both sides with respective fastening areas 23. The projection 11 can be inserted into the receptacle 21 along the insertion direction 41.

[0039] This creates electrical contact between the projection 11 and the receptacle 21 or its contact elements 22, as well as fixation of the projection 11 in the receptacle 21 along a first translational degree of freedom 40, which extends along the insertion direction 41. Depending on the specific structural embodiment, the fastening shown can also be used to realize fixations along the second translational degree of freedom and the third translational degree of freedom.

[0040] On the side of the second electrical contact element 20 facing away from the contact elements 22, the second electrical contact element 20 comprises a compensation device 50, which in the embodiment shown here is implemented as a section of reduced flexural rigidity 51. This section of reduced flexural rigidity 51 is implemented as an S-shape or meander shape of the material of a bending element 52 of the second electrical contact element 20.

[0041] It is provided that the compensation device 50 has a lower tensile stiffness than the connection stiffness of the realized mechanical fastening of the projection 11 in the receptacle 21, so that when an axial force acts on the two electrical contact elements 10, 20, a deformation of the compensation device 50 occurs rather than a release of the mechanical fixation of the projection 11 in the receptacle 21 and consequently a relative movement between the projection 11 and the receptacle 21 along the first translational degree of freedom 40. This ensures, among other things, that in the event of temperature-related displacement of individual components of the plug connection unit 1, the electrical contact between the projection 11 and the receptacle 21 is not released.

[0042] The deformation of the compensation device 50, however, enables a relative movement 70 between the contact elements 22 and a line section 60 connected to the contact elements 22 via the bending element 52.

[0043] The Fig. 2 and Fig. 3 show different sections of the second electrical contact element 20. Fig. 2 shows an enlarged view of an embodiment of the realization of the electrical contact between the fastening areas 23 of the contact elements 22 and the projection 11 and thus also the mechanical fixation of the projection 11.

[0044] It is shown here that the fastening areas 23, which are designed as resilient legs of the contact elements 22, have contact surfaces 24 extending at an angle to one another, which form an edge 25 between them that cuts into the surface of the projection 11. Accordingly, a deformation of the projection 11 occurs due to a wedge effect on the projection 11 caused by the contact surfaces 24 or their edge 25.

[0045] This deformation leads to an enlargement of the contact area of ​​the projection 11 in the receptacle 21, as well as to an increase in the connection strength between the projection 11 and the receptacle 21.

[0046] In Fig. 2 it is also evident that an acute angle 30 is realized between the contact elements and the longitudinal axis of the projection 11, which also corresponds to the orientation of the first translational degree of freedom 40, in order to facilitate an insertion process of the projection 11 into the receptacle 21 along the insertion direction.

[0047] Fig. 3 shows an enlarged view of a portion of the compensation device 50, namely two opposing side edges 53 of the bending element 52, on each of which a pressure element 54 is arranged facing each other. It can be seen that the distance between opposing pressure elements 54 is smaller than the distance between opposing side edges 53. The pressure elements 54 make it possible that when a high pressure force is introduced into the plug-in connection unit 1 along the insertion direction 41, as shown in Fig. 1, the pressure elements 54 come into contact with one another and can thus transmit the pressure force without causing a strong deformation of the section of reduced flexural rigidity 51 and thus its overloading.

[0048] Fig.Figure 4 shows the arrangement of the plug connection unit 1 on an electrical device, such as, for example, on a so-called electric axle for an electric-driven motor vehicle. Here, it can be seen that the plug connection unit 1 has a total of seven parallel-connected first electrical contact elements 10 and second electrical contact elements 20, which electrically contact one another in the manner described. Furthermore, it can be seen that the second electrical contact elements 20 lead into a circuit board 90 of a connector 80, via which the electrical device shown is electrically connected. Using the plug connection unit 1 shown, a so-called bypass on an electric axle can be realized, for example.

[0049] The plug-in connection unit proposed here and the electric drive device equipped with it provide solutions that enable a permanent electrical connection of contacts and thus the operation of the electric drive device in a simple, cost-effective and easy-to-assemble manner. List of reference symbols 1 plug-in connection unit 10 first electrical contact element 11 lead 12 Housing of the first electrical contact element 20 second electrical contact element 21 recording 22 Investment element 23 Mounting area 24 contact surface 25 edge 26 Housing of the second electrical contact element 30 acute angle 40 first translational degree of freedom 41 Insertion direction 50 Compensation device 51 Section of reduced flexural rigidity 52 Bending element 53 side edge 54 pressure element 60 line sections 70 Relative motion 80 plugs 90 board

Claims

[1] Plug connection unit (1), comprising at least one first electrical contact element (10) designed as a projection (11) and at least one second electrical contact element (20) designed as a receptacle (21) for the projection (11), which are designed to realize an electrically conductive connection and a mechanical fastening of the projection (11) in the receptacle (21) at least along a first translational degree of freedom (40) of the projection along its insertion direction (41) into the receptacle (21), and wherein at least one of the two contact elements (10, 20) comprises a compensation device (50) for enabling relative movements (70) of sections of this contact element (10, 20) along the first translational degree of freedom (40),which has a lower tensile stiffness than the connection stiffness of the realized mechanical fastening of the projection (11) in the receptacle (21), wherein the compensation device (50) has at least one section of reduced flexural stiffness (51) which imparts the reduced tensile stiffness to the compensation device (50), and the section of reduced flexural stiffness (51) comprises a meandering bending element (52), , characterized bythat a pressure element (54) is arranged on at least one of two side edges (53) of the meandering bending element (52) opposite one another along the first translational degree of freedom (40), for bearing against the respective opposite side edge (53) in the event of a pressure load on the bending element (52) in the direction of the respective other contact element (10, 20), wherein the second electrical contact element (20), the at least one section of reduced flexural rigidity (51) and the pressure element (54) lie in one plane. [2] Plug connection unit according to claim 1, characterized by that the receptacle (21) has at least one elastically effective contact element (22) for contact with the projection (11). [3] Plug connection unit according to one of the preceding claims, characterized by that the contact element (22) extends at an acute angle (30) to the axis of the first translational degree of freedom (40). [4] Plug connection unit according to one of claims 2 and 3, characterized by , that i) at least one of the contact elements (22) is designed to bear against the projection (11) with a surface contact, or ii) that at least one of the contact elements (22) is designed to bear against the projection (11) with an edge contact. [5] Plug connection unit according to one of the preceding claims, characterized by that the pressure element (54) is spaced from the respective opposite side edge (53) in the event that the bending element (52) is not subjected to pressure, and only comes into contact with the opposite side edge (53) when a certain pressure on the bending element (52) is exceeded. [6] Plug connection unit according to one of the preceding claims, characterized bythat the plug connection unit (1) has a plurality of the first electrical contact elements (10) and second electrical contact elements (20) which can be plugged into one another. [7] Electric drive device comprising at least one plug connection unit (1) according to one of claims 1 to 6.

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