US-20260128537-A1 - CONNECTOR WITH IMPROVED CONTACT SPRING ELEMENTS

US20260128537A1US 20260128537 A1US20260128537 A1US 20260128537A1US-20260128537-A1

Abstract

A connector for electromechanically connecting two contact devices, preferably with a polygonal cross-section, preferably plug-in tabs of busbars and/or PCBs is provided. The connector includes a main-connector body, which has a hollow shape and into which the contact devices can be inserted from both sides, and a contact spring element, mounted in the main-connector body. The contact spring element has a first frame, a second frame, and at least six flat springs connecting the first and second frames to each other. At least two flat springs arranged next to each other extend from a frame spar of the first frame to a corresponding frame spar of the second frame. At least the two flat springs arranged next to each other each have a larger current flow cross-section in the area assigned to a connection point of the contact devices than in adjacent areas of the corresponding flat spring.

Inventors

Florian Bruhn
Akshata Ankush Sangle

Assignees

iwis smart connect GmbH

Dates

Publication Date: 20260507
Application Date: 20251105
Priority Date: 20241106

Claims (15)

1 . A connector for the electromechanical connection of two contact devices, preferably plug-in tabs of busbars and/or PCBs, with a main-connector body that has a hollow shape and into which the contact devices can be plugged in from both sides, and with contact spring elements which is mounted in the main-connector body, wherein the contact spring elements have a first frame, a second frame and at least six flat springs connecting the first and second frames to each other connecting the first and second frames to each other, wherein at least two flat springs arranged next to each other extend from a frame spar of the first frame to a corresponding frame spar of the second frame, and wherein at least the two flat springs arranged next to each other each have a current flow cross-section that is enlarged in comparison to adjacent areas of the corresponding flat spring in their area assigned to a connection point of the contact devices.
2 . The connector according to claim 1 , wherein the respective enlarged current flow cross-section of the at least two flat springs arranged next to each other is formed by means of a crossbar connecting the at least two flat springs arranged next to each other.
3 . The connector according to claim 1 , wherein the crossbar has a width (B) which is in the range of 5% to 30% of the length (L) of the associated flat springs.
4 . The connector according to claim 2 , wherein the flat springs of the contact spring elements have two or more main bends which each project inwardly into a plug-in space of the main-connector body and follow one another in the plug-in direction, with a corresponding transition bend between them, such that at least one main bend can be brought into contact with one contact device and at least the transition bend rests against or is connected to the main-connector body in the area associated with the connection point of the contact devices.
5 . The connector according to claim 2 , wherein at least the transition bend in the area associated with the connection point of the contact devices has a flattened section for abutment against or connection to the main-connector body.
6 . The connector according to claim 5 , wherein the length (A) of the flattened section measured in the plug direction corresponds to at least 5% of the length (L) of the corresponding flat spring.
7 . The connector according to claim 4 , wherein the transition bends are connected to each other by means of the crossbar in the area of the at least two flat springs arranged next to each other, which is associated with the connection point of the contact devices.
8 . The connector according to claim 1 , wherein at least one flat spring has a stop tab molded onto it, which protrudes inwardly into the plug-in space of the main connector body and is designed as an insertion stop for at least one of the contact devices.
9 . The connector according to claim 8 , wherein the stop tab is arranged in extension of the crossbar.
10 . The connector) according to claim 4 , wherein at least one of the flat springs has, at least transversely to the longitudinal extension of at least one main bend has a projection which protrudes inwardly into the plugging space of the main-connector body and, in this area, forms the main contact zone of the flat spring and contact device when plugged in.
11 . The connector according to claim 10 , wherein the projection is formed by means of an embossment in the at least one flat spring.
12 . The connector according to claim 10 , wherein the embossment forms a projection protruding outwardly from the contact spring elements, whereby contact zones separated from each other by the embossment are created on the inside of the associated flat spring.
13 . The connector according to claim 1 , wherein only on the wide side of the contact spring elements at least two of the flat springs arranged next to each other have an enlarged current flow cross-section in their area assigned to a connection point of the contact spring device.
14 . The connector according to claim 2 , wherein only on the wide side of the contact spring elements at least one flat spring has an embossment.
15 . The connector according to claim 1 , wherein the main-connector body is made of an electrically non-conductive material.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to foreign German patent application No. DE 102024132351.5, filed on Nov. 6, 2024, the disclosure of which is incorporated by reference in its entirety. FIELD OF THE INVENTION The present invention relates to a connector for the electromechanical connection two contact devices, preferably plug-in tabs of busbars and/or PCBs. BACKGROUND In electromechanical contacting of, for example, contact tabs or busbars, it is common for a contact shoe, contact connector, etc., formed from sheet metal to have a contact spring arrangement (for example, in the form of a contact or lamella cage) inside so that the mating contact is inserted under spring preload. In the case of flat, particularly rectangular plug-in tabs, the corresponding spring-loaded contacting of the upper and lower sides of the plug-in tab is provided. In many cases, several spring tabs in the form of flat/lamellar springs are produced to provide the corresponding spring contacting. Examples of such arrangements can be found in DE 10 2005 033 696 A1 and DE 10 2019 119 405 A1. What these designs have in common is that they are each adapted to the corresponding plug-in element. However, the designs shown there are not suitable for directly or immediately connecting two contact tab tongues. Due to advancing electrification, including in the automotive sector, there is increasing demand for high-voltage and high-current applications. In particular, busbar rails must be connected directly to each other. Heat generation in such connectors is often a limiting factor for acceptable current transmission. SUMMARY OF THE INVENTION The present invention therefore aims to improve a corresponding connector in terms of its permissible current transmission rate. This task is solved by a connector according to claim 1. The connector for electromechanically connecting two contact devices, preferably with a polygonal cross-section, preferably plug-in tabs of busbars and/or PCBs, comprises a main-connector body, which has a hollow shape and into which the contact devices can be inserted from both sides, and a contact spring element, which is mounted in the main-connector body. The polygonal cross-section may also have strongly rounded corners, e.g., a rectangle with strongly rounded corners. The contact spring elements have a first frame, a second frame, and at least six flat springs connecting the first and second frames to each other, wherein at least two flat springs arranged next to each other extend from a frame spar of the first frame to a corresponding frame spar of the second frame. At least the two flat springs arranged next to each other each have a current flow cross-section that is larger than adjacent areas of the corresponding flat spring in the area assigned to a connection point of the contact devices. The inventors have demonstrated through experiments that increasing the current flow cross-section of the flat springs precisely in the area that represents the actual connection point between the two contact devices reduces the temperature load on the connector under otherwise identical boundary conditions. Accordingly, this simple measure allows the connector according to the invention to be subjected to higher loads and thermal limits are reached less quickly. The increase in the current flow cross-section only needs to take place in this area of the flat springs. The remaining areas of the flat springs can manage with a smaller current flow cross-section. The “joint” between the two contact devices within the connector is considered to be the connection point, although the two contact devices do not necessarily have to touch each other. In such connections, the two end faces of the contact elements, in particular the plug-in tabs, are usually opposite each other. There is no overlap of the contact elements. Preferably, the enlarged current flow cross-section of the at least two flat springs arranged next to each other can be formed by means of a crossbar connecting the at least two flat springs arranged next to each other. The corresponding spring tongues are formed contiguously in this area by means of the crossbar. Such a crossbar can be produced very easily, particularly in a stamped-bent design of the contact element. If the crossbar is also supported by the main-connector body and the latter is sufficiently thermally conductive, additional heat can be dissipated. A material bond between the crossbar and the main-connector body is also possible. According to one embodiment, the crossbar can have a width in the range of 5% to 30%, preferably in the range of 15% to 20%, of the length of the associated flat springs. The length of the flat springs is essentially determined by the distance between the first and second frames. This results in a considerable increase in the current flow cross-section in this section and thus improved thermal properties. Favourably, the flat springs of t