Shielding sleeve for contacting shielding elements

Description

[0001] The invention relates to a shielding sleeve for contacting shielding elements between cables and connectors, comprising a spring region with at least one spring element and a sleeve region with a cylindrical and at least partially circumferential extension.

[0002] Electrical contact elements, contact arrangements, plug-in and detachable cable connection elements and suitable manufacturing processes are available in the known state of the art.

[0003] Contacts generally comprise at least one electrically conductive contact section for detachable, temporary, or plug-in connection to a corresponding mating contact element, and a shaft section adjoining the contact section for attaching an electrical line to the contact. Such a contact, plug-in contact, or high-current contact can be used in a wide variety of applications, for example, for circuit board contacting, in vehicle wiring harnesses, on or in a charging plug or charging socket, for example, for charging an electrically powered vehicle, etc.

[0004] Depending on the application, a wide variety of requirements must be met, often cumulatively: reliability, fatigue strength, detachability, reduced resistance, resistance to external influences and environmental conditions, resistance to contact corrosion, and many more. One criterion that must be met almost always is electromagnetic compatibility (EMC).

[0005] Electromagnetic compatibility means the (largely) absence of influences on other devices and equipment that could lead to unwanted or intentional malfunctions of electrical or electronic equipment, for example, due to electrical, magnetic, or electromagnetic fields and processes. This already includes influences caused by currents or voltages. The European EMC Directive defines electromagnetic compatibility as follows: "the ability of an apparatus, installation, or system to operate satisfactorily in its electromagnetic environment without itself causing electromagnetic disturbances that would be unacceptable for all other apparatus, installations, or systems in that environment." (Source: EU Directive 2014 / 30 / EU Article 3 No. 4 of February 26, 2014).

[0006] Electromagnetic interference can also originate from plugs, connectors, contacts, and cables, as these carry current. To ensure electromagnetic compatibility, devices, cables, and connectors are often shielded. Shielding electrical devices, equipment, and rooms serves to keep electrical and / or magnetic fields away from them, or conversely, to protect the surrounding area from the fields emanating from the equipment.

[0007] In the area of ​​connectors, plug contacts and contacts, the shielding devices of cables must be continued without gaps or interruptions to ensure that electromagnetic emissions are reduced or prevented.

[0008] To meet this requirement, various approaches have been pursued in the state of the art. Basically, a coupling impedance is implemented between the inner, current-carrying conductor (core, stranded wire) and the outer cable shield (outer conductor, cable shield) based on the principle of the Faraday cage.

[0009] For many applications, adequate shielding of connectors is necessary to improve electromagnetic compatibility. For this purpose, electrical connectors are typically overmolded with an electrically conductive sheath or inserted with a metallic braid.

[0010] To contact the shielding elements of the lines or cables in the connector area or to seamlessly continue these cable shields, sleeves, spring sleeves, shielding sleeves, and shielding springs can be used to continue the shielding of the lines with the shielding measures of the connector housing and / or the mating connector and / or the cable to be contacted. In addition to the actual shielding function, various additional requirements may apply depending on the additional functions implemented: Application of clamping and pressing forces for holding and fixing the cable in the connector housing, corrosion resistance, particularly in aggressive environments such as moisture, salt, acid, fatigue strength and minimized relaxation and creep processes in the material of the spring sleeve, aging resistance, good current conduction properties, low resistance.

[0011] WO 2007 / 107196 A1 shows a solution in which the outer surface of the contact chamber is completely coated with a thin, electrically conductive layer. The layer thickness is small compared to the thickness of the contact chamber walls. The abutting surfaces on the outer surface of the contact chamber are shielded with an overlap wall section, which is also conductively coated on its side facing the abutting surfaces, preferably with the same layer as the outer surface of the contact chamber. Preferably, a metallization is provided as the conductive layer. The overlap wall section(s) intercept electromagnetic waves escaping through the slots between adjacent abutting surfaces, which cannot be avoided due to manufacturing technology, and the entry of such radiation into the contact chamber is prevented or at least impeded.The overlap wall section represents a kind of labyrinth for electromagnetic radiation. In addition to its shielding function, the electrically conductive coated outer surface of the contact chamber also has the function of transmitting the shielding from a connecting cable connected to the electrical connector to an interface to an application connected via the connector.

[0012] For additional shielding, a radially resilient sleeve can be used, which presses the shielding and outer conductor of the connecting cable radially inward onto the outer surface of a conductive collar section. It is important that the sleeve exerts a resilient effect and thus exerts a contact force radially inward from circumferentially spaced tabs. The tabs press the shielding of the connecting cable onto the outer surface of the collar section.

[0013] A spring sleeve can be provided to transfer the shielding to the application interface. The spring sleeve is pulled over a neck of the contact chamber and is designed to spring both radially inward and radially outward. For this purpose, spring-loaded tabs are provided on the inner and outer circumferences of the spring sleeve in the radial direction. In addition to transferring the shield, the spring sleeve also fulfills the function of tolerance compensation in the interface to the application thanks to the spring-loaded tabs provided on the outer circumference. When assembled, the spring sleeve is arranged concentrically to the longitudinal center axis of the socket-type contact.

[0014] A shielded connector assembly is also disclosed in DE 101 40 685 C1. It shows a cable connection with an inserted plug-in coupling, with one coupling part having a protective sleeve and the other coupling part having two coaxially arranged guide sleeves and a cable entry. To achieve an overall assembly shielded against interference, the components are connected both electrically and fluidically via fluid seals and subsequent electrical contacts at their transitions.

[0015] DE 197 37 321 C2 discloses a single-pole power connector combination with a panel-mounted plug and a loose plug, each having an aluminum housing, wherein a front end portion of the panel-mounted plug can be inserted coaxially into a socket portion of the loose plug. An insulating plug insert is arranged in each panel-mounted plug and the loose plug, which receives a contact element connected to a connecting cable. The panel-mounted plug and the loose plug each have a shielding sheath of the respective connecting cable in the form of a tubular spring, which creates a conductive connection between the shielding sheath and a screw-in socket screwed into the housing. A further tubular spring is inserted into the front socket portion of the loose plug, which forms an effectively closed shield for the connector combination when the plugs are mated together.

[0016] A high-frequency connector for symmetrical, shielded cables is presented in DD 282 783 A5. The connector components have a first and a second spring sleeve, each provided with a continuous longitudinal slot and a circumferential projection on the front ends of their inner wall, one projection of which engages in the circumferential groove of the first or second insulating part and the other projection of which engages behind a first or second flange with a pipe socket bearing an external thread, the first and second metal cylinders sit on the first or second spring sleeve and each strike one end of the first or second spring sleeve with their annular end face facing away from the plug-in direction, and a nut on the external thread of the pipe socket holds the first or second metal cylinder without play and the clamping sleeve arranged on the first metal cylinder with axial play.

[0017] A socket with a shoulder pointing against the plug-in direction sits on the outer shielding braid of a symmetrical, shielded cable to be connected to the RF connector and is received inside a cylindrical shaft connected to the pipe socket in such a way that the turned-back end of the shielding braid pointing against the plug-in direction is located between the outer wall of the socket and the inner wall of the cylindrical shaft and the cylindrical shaft, the turned-back end of the shielding braid and the socket sitting on the shielding braid of the cable / are crimped together.

[0018] The spring sleeves, shield sleeves, and shield springs available in the state of the art suffer from various disadvantages depending on their design. Many solutions are complex, costly, and difficult to manufacture due to their multi-part design and / or geometric configuration. If clamping functions are implemented in an integrated manner using the spring sleeves, shield sleeves, and shield springs, the fatigue strength requirements are often not met. Furthermore, existing solutions carry the risk that electrical resistance properties lead to increased power losses.

[0019] Conventionally designed spring sleeves are subject to fatigue over their lifetime due to relaxation and creep processes in the material, resulting in a reduction in contact pressure. This leads to an increase in contact resistance and, at the same time, in the temperature of the spring. In extreme cases, the contact can fail, causing the system to shut down.

[0020] Further printed prior art in the present technical field, which the .

[0021] The preamble of claim 1 is reflected in the documents DE 10 2011 102 566 A1 , DE 10 2012 105 258 A1 and EP 0 052 980 A2 revealed.

[0022] The object of the invention is to further develop spring sleeves, shielding sleeves, shielding springs for contact arrangements, contacts, plug connections, so that the aforementioned disadvantages of the prior art are at least partially reduced and the functional requirements are better met.

[0023] To achieve this object, the invention proposes a shielding sleeve according to claim 1.

[0024] The invention recognizes that the geometric design of the umbrella spring is suitable not only for the tasks the transfer of the EMC shielding current from the cable sheath to the housing of the connector plug and / or the fixing, locking in the form of a cable retraction protection to protect against removal of the outer insulation and / or the current transfer in the shielding to implement the Faraday principle in the higher frequency range or the earthing currents to solve the problem, but also to support cost-effective manufacturability and the reduced number of parts through the integrated design of the spring area and the sleeve-shaped section.

[0025] The teaching of the invention is associated with a number of further advantages. In particular, fatigue strength and permanently maintained spring tension are reliably achieved. This is a result of the creep processes and relaxation of the spring, which are prevented or minimized due to the roof-shaped and / or triangular shape in the spring area. The increased and permanent contact pressure of the contact points also supports a reliable and reduced contact resistance over the service life. Furthermore, the temperature resistance and / or the temperature-dependent preload reduction of the spring effect are improved by supporting the contact area via the triangular shape, making it less susceptible to high temperatures.

[0026] Due to the increased contact pressure of the spring blade against the housing of the plug connection or the contact partner of the shielding, a lower electrical resistance in the contact area results because possible surface contamination, oxide layers, for example aluminum oxide, are practically penetrated and rubbed through.

[0027] The invention is explained in more detail below using four exemplary embodiments in conjunction with the figures. These show: Fig. 1 shows a perspective view of a first exemplary embodiment of the shielding sleeve according to the invention with a spring region, spring element region, and a sleeve region; Fig. 2 shows a sectional view of the front view of the first exemplary embodiment of the shielding sleeve according to the invention with a spring region, spring element region, and a sleeve region; Fig. 3 shows a sectional view of the front view of the first exemplary embodiment of the shielding sleeve according to the invention within an assembled and plugged-in plug connection; Fig. 4 shows a perspective view of a second exemplary embodiment of the shielding sleeve according to the invention with a spring region, spring element region, and a sleeve region; Fig. 5 shows a sectional view of the front view of the second exemplary embodiment of the shielding sleeve according to the invention within an assembled and plugged-in plug connection;6 shows a perspective view of a third exemplary embodiment of the shielding sleeve according to the invention with a spring region, spring element region, and a sleeve region; Fig. 7 shows a sectional view of the front view of the third exemplary embodiment of the shielding sleeve according to the invention with a spring region, spring element region, and a sleeve region; Fig. 8 shows a sectional view of the front view of the third exemplary embodiment of the shielding sleeve according to the invention within an assembled and plugged-in plug connection; Fig. 9 shows a perspective view of a fourth exemplary embodiment of the shielding sleeve according to the invention with a spring region, spring element region, and a sleeve region; Fig. 10 shows a sectional view of the front view of the fourth exemplary embodiment of the shielding sleeve according to the invention with a spring region, spring element region, and a sleeve region;11A top view of an exemplary flat semi-finished product for producing a shielding sleeve according to the invention.

[0028] Figure 1 depicts a perspective view of a first embodiment of the shielding sleeve 1 according to the invention with a spring region, spring element region 10, and a sleeve region 20. The spring region 10 and the sleeve region 20 are formed in one piece and are manufactured based on a semi-finished flat 100, preferably by forming.

[0029] The sleeve region 20 is cylindrical in shape and thus compatible with a cable or wire with an inner core and a shielding electrically separated by insulating material, usually in the form of a metal mesh. Opposite the spring element region 10 and at the end, the sleeve region 20 can have one or more bevels 21. The at least one bevel 21 provides a mechanical stop that limits the sliding path of the shielding sleeve 1 onto a cable and supports the defined position of the shielding sleeve 1 on the cable.

[0030] The Figure 1The shielding sleeve 1 shown is designed in a segmented manner in the region of the sleeve section 20 within the scope of one possible embodiment of the invention. By deforming or reshaping the preferably flat starting material, at least one segment 22, preferably a plurality of segments 22, is formed in the cylindrical region of the sleeve section 20. In the example shown, segments 22 are present around the entire circumference of the sleeve section 20.

[0031] Figure 2 shows the sectional view of the front view of the first embodiment of the shielding sleeve 1 according to the invention with a spring area, spring element area 10 and a sleeve area 20 made of Figure 1The segments 22 are integral elements of the shielding sleeve and preferably extend over the entire axial length of the sleeve section. The segmented design of the sleeve section 20 makes it possible to arrange a bevel 21 and / or a spring element 13 at each end of the axial segment length.

[0032] The at least one spring element 13 of this first exemplary embodiment is formed by a first and at least one second leg, spring leg 12. The first and the at least one second leg 12 are arranged relative to one another in such a way that a roof-shaped geometry is formed. This exemplary embodiment, together with a third leg 12, which adjoins the sleeve section 20 with its axial extension, forms a triangular basic shape.

[0033] The roof-shaped and / or triangular shape in the spring area prevents or minimizes creep and relaxation of the spring, with the result that the fatigue strength is increased and / or the spring force and contact pressure of the contact points remain largely constant over the long term.

[0034] A rounded portion or edge 11 can be formed at the end of a leg 12. The rounded portion 11 enables, better than a blunt end of the leg 12, the sliding relative movement on the respective contact surface upon deformation of the spring element 13 and / or the support of the spring element 13 via the contact point of the rounded portion or edge 11 on the respective contact surface, which in the illustrated embodiment is the outer surface of the sleeve area.

[0035] Figure 31 comprises the sectional view of the front view of the first exemplary embodiment of the shielding sleeve 1 according to the invention within an assembled and plugged-in connector. The shielding sleeve 1 is pushed onto the cable 200 and encompasses a section of the outer insulation 204. The axial position of the shielding sleeve 1 in the sliding-on direction is mechanically defined or fixed by the bevel 21 adjacent to the outer insulation 204.

[0036] The cylinder-like outer surface of the sleeve portion 20 is at least partially in electrically conductive contact with the cable shielding 203. For this purpose, the cable shielding 203 is exposed and folded over by previously removing a portion of the outer insulation 204.

[0037] The spring element region 10 of the shielding sleeve 1 is deformed at least in some regions elastically and possibly also plastically by a compression distance in the radial direction, so that the elastic recovery properties of the spring element region 10 exert a contacting force on the contact partner—here, the inner housing surface of the connector plug. The at least one spring element 13 of the spring region 10 rests with its end-side rounded portion 11 against the outer surface of the sleeve region 20 and is thus supported thereon.

[0038] The embodiment shown has a bulge, calotte 14 in the gable section of the roof-shaped arrangement of the spring element 13. In this way, two advantages can be achieved: 1. Due to the reduced contact area resulting from the point contact area, the surface pressure is significantly increased and particularly reliable contact is supported; 2. The bulge 14 positively influences the elastic spring behavior due to the resulting notch stress, i.e., the elastic deformation component is increased compared to the situation without bulge 14.

[0039] Figure 4Illustrates a perspective view of a second embodiment of the shielding sleeve 1 according to the invention, comprising a spring region, spring element region 10, and a sleeve region 20. The inventive concept is implemented here by a plurality of roof-shaped spring lamellae and spring elements 13, which are formed in an axially continuous extension on the sleeve region 20. A triangular geometric configuration of the spring elements 13 of the spring region 10 is achieved in the assembled state by the interaction with the outer insulation 204 of the electrically conductive cable 200 by applying the spring lamellae 13 to the outer insulation 204. The application is realized by contact surfaces at the ends of the spring lamellae 13 via the respective rounding or edging 11.

[0040] The triangular geometric situation of the spring element area 10 in the assembled state shows Figure 5The illustrated sectional view of the front view of the second embodiment of the shielding sleeve 1 according to the invention within an assembled and plugged-in connector utilizes the previously described advantages of the invention through the triangular geometric situation of the spring element region 10.

[0041] Figure 6 comprises the perspective view of a third embodiment of the shielding sleeve 1 according to the invention with a spring region, spring element region 10 and a sleeve region 20. Deviating from the first embodiment of the invention, the end side of the spring elements 13 is geometrically changed here.

[0042] At the end of a leg 12, a rounded portion or edge 11 can be formed, which, unlike the first embodiment, is directed toward the inside of the shielding sleeve 1. In this way, the contact surface is achieved by an end-side spring element region that is largely parallel or plane-parallel to the contact surface on the sleeve region 20. In this way, too, and functionally comparable to the design of the rounded portion 11, this enables the sliding relative movement on the respective contact surface upon deformation of the spring element 13 better than a blunt end of the leg 12.

[0043] Figure 7 shows the sectional view of the front view of the third embodiment of the shielding sleeve 1 according to the invention from Figure 6with a spring region, spring element region 10, and a sleeve region 20. Analogous to the first exemplary embodiment, the at least one spring element 13 of the third exemplary embodiment is also formed by a first and at least one second leg, spring leg 12. The first and the at least one second leg 12 are arranged relative to one another in such a way that a roof-shaped geometry is formed. This exemplary embodiment, together with a third leg 12, which adjoins the sleeve section 20 with its axial extension, forms a triangular basic shape.

[0044] The roof-shaped and / or triangular shape in the spring area prevents or minimizes creep and relaxation of the spring, with the result that the fatigue strength is increased and / or the spring force and contact pressure of the contact points remain largely constant over the long term.

[0045] Figure 8illustrates the sectional view of the front view of the third embodiment of the shielding sleeve 1 according to the invention within an assembled and plugged-in connector.

[0046] Figure 9 shows the perspective view of a fourth embodiment of the shielding sleeve 1 according to the invention with a spring area, spring element area 10 and a sleeve area 20. The inventive idea is implemented here by a geometric variant of the second embodiment, which in Figure 4 and 5 The fourth embodiment comprises a plurality of roof-shaped spring lamellae, spring elements 13, which are formed in an axially continuous extension on the sleeve region 20.

[0047] The roof-shaped geometric design is complemented by a flattened portion 15, which replaces the roof peak within the roof shape. The flattened portion 15 modifies the elastic behavior of the spring slats 13 in different ways, depending on the design.

[0048] One possibility is that the spring characteristic curve is directed towards a flatter spring characteristic curve compared to a spring lamella 13 with a roof peak according to the second embodiment, as in Figure 4 and 5 shown, is modified. The flatter spring characteristic curve results in a greater spring travel with the same force application compared to a spring plate 13 with a roof peak. This is the result of the reduced flexural rigidity of the spring plate 13 and / or the modified force application point, realized at the bulge 14 due to the length ratios of the legs 12.

[0049] A triangular geometric situation of the spring elements 13 of the spring region 10 with flattening 15 is also achieved with the fourth embodiment in the assembled state by the interaction with the outer insulation 204 of the electrically conductive cable 200 by applying the spring lamellas 13 to the outer insulation 204. The application is realized by contact surfaces at the end of the spring lamellas 13 via the respectively formed rounding, edging 11.

[0050] Figure 10comprises the sectional view of the front view of the fourth embodiment of the shielding sleeve 1 according to the invention with a spring region, spring element region 10 and a sleeve region 20 within an assembled and plugged-in plug connection and utilizes the previously described advantages of the invention through the triangular geometric situation of the spring element region 10 in conjunction with the flattened portion 15 for the targeted modification of the spring-elastic behavior of the spring lamellae 13, in different ways depending on the design. The geometric configuration shown has a longer leg 12 between the sleeve region 20 and the flattened portion 15 than the length of the leg 12 between the flattened portion 15 and the rounded portion 11. This results in a flat spring characteristic curve, iethe elasticity and deformability are increased and the spring travel is increased compared to the formation of a roof peak with the same resulting force acting radially to the umbrella sleeve 1.

[0051] Figure 11 shows a top view of an exemplary flat semi-finished product 100 for producing a shielding sleeve 1 according to the invention. The semi-finished product, preferably in the form of a stamped part, is prepared by its contouring for the subsequent forming process, such as bending and folding. Suitable materials must be electrically conductive, formable, and have spring-elastic properties. Among other materials, copper-nickel alloys are considered, which can optionally be hot-dip tinned for corrosion resistance, for example, CuNiSiMg R650. Reference symbol

[0052] 1Shield sleeve 10Spring area, spring element area 11Rounding, edging 12Legs, spring legs 13Spring element 14Bump, calotte 15Flattening 20Sleeve area, sleeve-shaped area, sleeve section 21Fold 22Segment 100Semi-finished, flat, semi-finished flat, stamped part 200Cable, electrically conductive cable 201Core, inner electrical conductor 202First, inner insulation 203Cable shield, outer electrical conductor 204Second, outer insulation

Claims

1. Shielding sleeve (1) for contacting shielding elements between lines and plug connectors, having a spring region (10) with a multiplicity of spring elements (13), and having a sleeve region (20) with a cylindrical and at least regional circumferential extent, wherein the spring region (10) and the sleeve region (20) are formed in one piece, wherein the spring elements (13) are formed in a roof-shaped arrangement by at least two spring limbs (12), wherein the at least one spring element (13) has a third spring limb (12) such that the roof-shaped arrangement of the spring element (13) is supplemented to form an at least regionally closed triangle, wherein the third spring limb (12) is in the form of an element with a linearly continuing longitudinal extent of the sleeve region (20), characterized in that the spring elements (13) have a rounding (11) at an end such that a sliding relative movement and support of the respective spring element (13) at an abutment surface of the sleeve region (20) is assisted, wherein the roof-shaped arrangement of the at least one spring element (13) has a convexity (14) in its gable portion.

2. Shielding sleeve (1) for contacting shielding elements according to Claim 1, characterized in that the abutment surface for supporting the spring element (13) is a constituent part of the third spring limb (12) and / or of the sleeve region (20).

3. Shielding sleeve (1) for contacting shielding elements according to Claim 1, characterized in that the sleeve region (20) is formed by at least two segments (22).

4. Shielding sleeve (1) for contacting shielding elements according to Claim 3, characterized in that at least one segment (22) has an angled portion (21) at an end such that a mechanical stop is formed.

5. Shielding sleeve (1) for contacting shielding elements according to Claim 3, characterized in that at least one segment (22) has associated geometrically, and in terms of its aligned longitudinal extent, therewith a spring element (13).

6. Shielding sleeve (1) for contacting shielding elements according to Claim 3, characterized in that the segment width in the circumferential direction is greater than the spring-limb width of the spring element.

7. Shielding sleeve (1) for contacting shielding elements according to Claim 1, characterized in that the shielding sleeve (1) is formed from a flat semi-finished product (100) by working and / or edging and / or deep drawing and / or folding.

8. Shielding sleeve (1) for contacting shielding elements according to Claim 7, characterized in that the flat semi-finished product (100) is a stamped part.

9. Shielding sleeve (1) for contacting shielding elements according to Claim 7, characterized in that the flat semi-finished product (100) consists of a hot-dip-tinned copper / nickel alloy, in particular CuNiSiMg R650.

10. Plug connection with EMC properties, having at least one shielding sleeve (1) according to one of the preceding claims.