Contact partner combination

Abstract

The invention relates to a contact partner combination for an electrically conductive connector, comprising a socket and a plug corresponding to the socket, and a wave sleeve arranged between the contact surfaces of the socket and the plug, wherein the plug is designed as a helical pin with the property of deforming upon temperature change, and the wave sleeve is designed both to transmit the temperature-induced deformation of the helical pin as a change in contact normal force to the contact surface of the socket and to limit the magnitude of the contact normal force by elastic deformation. The invention further relates to a connector with such a contact partner combination.

Description

[0001] The invention relates to a contact partner combination for an electrically conductive plug connection, comprising a contact socket and a contact plug corresponding to the contact socket, and a wave sleeve arranged between the contact surfaces of the contact socket and the contact plug. The invention further relates to a plug connection with such a contact partner combination.

[0002] For contacting or creating detachable electrically conductive connections, plug connectors, contact elements, pole connectors, sockets, etc., are used in a wide variety of designs and variants. Particularly, but not exclusively, for electrical contacting tasks in the higher power range, contact systems have been developed that are based on circular contact geometries for receiving a contact pin and whose starting material consists of a planar contact grid that is hyperbolically twisted into the circular contact geometry. These contact systems, known as RADSOK, are characterized by robust and high-density contact formation due to the considerable contact area with the respective contact pin. Alternatively, instead of the hyperbolic twisting, inwardly directed lamellar geometries are known, whose lamellar contact grid is radially symmetrical.

[0003] These contact geometries, preferably used as high-current contact sockets, are therefore known as radial contact sockets or hyperbolic contact sockets.

[0004] RADSOK contact systems of the aforementioned type are received into connector socket sleeves via their generally cylindrical outer contours and achieve external contact via the cylindrical surfaces. DE 10 2007 051 266 B4 is based on the fundamental idea of ​​providing a single connector socket sleeve designed to accommodate different lamellar contact cages in the form of RADSOK contact sockets, which make contact with the inside of the socket.

[0005] A comparable basic structure is shown in DE 20 2006 100 095 U1. The subject matter of the invention here is the coupling, connection, and contacting of the cylindrical lamellar cage "floating" within the receiving connector socket sleeve by fixing only one of the respective end flanges in the socket, for example, by press fit. An electrical connector socket comprising a cylindrical socket sleeve is provided, which is designed with a receiving space in which a cylindrical lamellar cage with a plurality of parallel contact lamellae is inserted, wherein the lamellar cage has a first and second circumferential flange between which the contact lamellae extend. The lamellar cage is fixed at one end at least axially and preferably also rotationally fixed in the socket sleeve and thereby clamped.The lamellar cage is attached to the bushing sleeve and, at the opposite end, has an axial sliding bearing that is rotatable at least through a certain angle. Preferably, the lamellar cage is attached to the inner wall of the bushing sleeve by means of a fastening element on the sleeve side, using a flanged web.

[0006] Especially in high-current contact applications—for example, charging batteries in electric vehicles or connecting the vehicle battery to the vehicle's electrical components—reliable electrical contact between the connectors is crucial. Such connectors and their contact elements, which often consist of one or more pairs of pins and sockets, are subject to various influences, such as mechanical stress, vibrations, shocks, and aging. Significant temperature fluctuations, caused by environmental conditions or by self-heating due to the electrical current flow and the inherent resistance of the current-carrying components, are also possible.Self-heating can be particularly relevant at the contact points, as the contact areas are small due to the contact force, resulting in a high resistance almost geometrically induced by the contact. For this reason, it is crucial that the contact force – more precisely, the normal contact force – is as high as possible and remains constant to press the contact partners, usually formed by a contact pin and a contact socket, firmly together at their contact surfaces for electrical connection.

[0007] The contact sockets available in the prior art, such as the aforementioned RADSOK sockets or their plug-in contacts (plug-in pins), utilize both formative shaping processes like stamping and rolling, and suitable materials with spring properties to generate the desired spring action through restoring forces. These forces are used to create preferably elastic contact forces between the contact partners at their contact surfaces. The performance of the plug-in connection is limited by temperature effects, as higher temperatures cause a loss of spring force due to relaxation processes, material creep, and residual stress reduction. This is particularly true for copper and copper alloys, since copper, in addition to its generally low elasticity, becomes "soft" even at low temperatures.

[0008] If the plug contact partners are designed in this way and made from materials such as spring steel, it is indeed possible to generate very high normal contact forces that reliably press the contact surfaces of the plug contact partners together, but assembly problems often arise because plugging the contact partners together requires high insertion forces, which make assembly difficult or require the use of tools.

[0009] To mitigate the problem of decreasing contact normal forces under temperature influence, contacting solutions have been developed in which the contacting elements or additional components deform as a result of a temperature increase, thereby increasing the contact force while simultaneously reducing the assembly force required when mating the connector at lower temperatures. EP 2 461 427 B1 discloses a self-deforming high-current contact based on the approach of achieving low mating forces at room temperature for assembly and high contact force or contact normal force during operation, particularly under conditions of increased self-heating and elevated ambient temperatures, through the design of the high-current contact and the provision of a connector element that deforms automatically with rising temperature.

[0010] The contact normal force increases almost automatically as soon as the temperature rises. The proposed high-current contact serves to transmit current from a power source to an electrical conductor of a current collector. Thus, the high-current contact, together with the corresponding contact pin, serves both as a mechanical connection and as an electrical contact between the current collector and the power source via an electrical contact surface between the high-current contact and the contact pin. By increasing the mechanical connection through temperature-induced deformation of the high-current contact or its self-deforming components, particularly a ring-shaped element, as the temperature of the high-current contact rises due to current flow, the material-induced loss of contact normal force is counteracted, and the contact force is at least maintained, and in some cases even increased.At the same time, assembly is possible at low temperatures with reduced insertion force.

[0011] A similar approach is pursued in DE 10 2005 032 462 A1. This patent teaches how to design the contact socket in such a way that at least the area of ​​the contact tips consists of a bimetallic strip. The area made of the bimetallic strip changes its shape due to the influence of heat. This change in shape is used to at least keep the contact normal force constant or to increase it.

[0012] FR 997 269 A discloses a contact partner combination according to the preamble of claim 1.

[0013] The contact solutions available in the prior art, which involve temperature-dependent changes in the contact normal force and are constructed using a combination of contact socket and contact pin, exhibit some significant disadvantages. Solutions often incorporate one or more components, such as rings or tubular parts, which influence the contact normal force due to temperature changes. These solutions frequently provide only small, or at least insufficient, increases in the contact normal force resulting from temperature changes caused by the temperature difference between before and after energization.

[0014] Other contact designs integrate the components of the contact or connector that deform under the influence of temperature into the contact socket component. With such geometric designs, the contact normal forces can only be influenced and, in particular, increased to a comparatively small extent by temperature-dependent deformation.

[0015] Contact solutions with temperature-dependent changes in contact normal force often present the problem, due to their geometry and materials, that the assembly process must be very precise and accurately guided, as angular errors can only be compensated for to a limited extent or concentric insertion is not possible. Furthermore, such contact solutions often exhibit reduced contact reliability when exposed to vibrations.

[0016] Another problem with temperature-induced changes in contact normal force through deformations achieved via multilayer materials or shape memory alloys can be that the changes in contact normal force become too high and deformations occur, at least partially, in the plastic range. If the deformation of multilayer metals or shape memory materials occurs in the plastic range, then these materials lose at least some of their temperature-induced deformation properties and / or the initiated deformation remains permanent even after returning to the temperature level before deformation, to the extent of the plastic deformation.

[0017] The object of the invention is to further develop existing contacting solutions with contact normal forces that can change due to temperature influence and to at least partially reduce the existing disadvantages.

[0018] The inventive solution to the problem proposes a contact partner combination according to claim 1 for an electrically conductive connector, consisting of at least one socket, a plug in the form of a helical pin, and a wave sleeve. The helical pin is inserted into the socket, and the wave sleeve is arranged between the contact elements of the socket and the helical pin. In the inserted state, the helical pin makes partial contact with the inner sections of the helical sleeve via its outer contact surface, while the socket makes partial contact with the outer sections of the wave sleeve via its inner contact surface.

[0019] In the contact partner combination, the contact socket is the outer element that supports the deformation forces and realizes the transmission of electrical energy.

[0020] The helical pin consists of a multilayer metal or a shape-memory alloy and has a cylindrical shape, at least in sections. Due to its multilayer metal or shape-memory material construction, the helical pin achieves the temperature-induced change in the contact force via deformation. This means that the temperature-dependent deformation of the helical pin is generated by using multilayer metals with different coefficients of thermal expansion and / or shape-memory alloys. The temperature change can be based on changes in the ambient temperature, an induced temperature change, and / or heating due to the ohmic resistance of the electrically conductive materials during the conduction of electrical energy.

[0021] The shaft sleeve, with its wave-shaped, open cross-section, functions as an elastic element between the helical pin and the contact bushing. Due to its elastic properties, it limits both the deformation caused by temperature changes and thus the contact normal force of the helical pin, as well as compensating for angular misalignments during and / or after assembly (connection). Furthermore, the shaft sleeve can dampen any vibrations and oscillations that may occur during operation, thereby reducing the introduction of such dynamic loads between the contact bushing and the helical pin. To achieve these elastic properties, the shaft sleeve is made of a highly elastic material, such as spring steel.

[0022] In the assembled state of the contact partner combination, the helical pin deforms due to temperature changes resulting from its construction from a multi-layer metal or a shape-memory alloy. This deformation occurs as radial expansion when the temperature increases and acts on the inner surface of the contact bushing via the shaft sleeve, which is designed as an elastic intermediate element, thereby increasing the contact normal force.

[0023] While the helical pin manages this temperature-induced change in contact normal force, the shaft sleeve ensures that the maximum contact normal force acting on the inner surface of the contact bushing is limited to a maximum force value due to the elastic deformation properties of the shaft sleeve. Simultaneously, the elasticity of the shaft sleeve provides the necessary range of motion for the helical pin during its deformation, ensuring that its deformation remains within elastic limits and no plastic deformation occurs. As a result, reliable contact and transmission of electrical energy are achieved, while the deformation-induced contact normal forces are limited to a maximum threshold.

[0024] To allow the essentially cylindrical helical pin the degree of freedom to expand radially due to temperature-induced deformation, and thus in the direction of the shaft sleeve surrounding it, the invention provides that the helical pin has at least one longitudinal slot, so that at least in some areas an open cross-section is present. The slot can extend through the cylindrical surface of the helical pin and have a helical shape. The helical design has the advantage that it does not engage or jam with a helical recess within the shaft sleeve if their helix pitches differ from each other.

[0025] The shaft sleeve extends axially largely parallel to and corresponding with the helical pin and the contact bushing. In the circumferential direction, a plurality of shafts are provided, preferably formed by successive radii of curvature or arc-shaped sections, each exhibiting a change of sign, thus creating the shaft structure.

[0026] The shaft sleeve has a longitudinal opening, forming an open cross-section. The opening of the shaft sleeve can extend parallel to the axis, but preferably it is inclined, similar to a helical shape. If the pitch of the opening and / or the inclined slots of the shaft sleeve is equal to the pitch of the helical slot, it is necessary to prevent them from essentially overlapping in the same position around the circumference, as this could cause them to jam and hinder or prevent deformation. The invention provides for this either by using an anti-rotation device to fix the shaft sleeve outside of this circumferential position, or by having different pitches for the helical opening of the shaft sleeve and the helical slot of the helical pin, thus preventing jamming.

[0027] Both the opening and the wave-like structure of the wave sleeve support a particularly high elastic deformation capacity, which can optionally be further increased by one or more slots, which, as already described, can have oblique, helical extensions.

[0028] The geometric designs of the shaft sleeve and / or the helical spine according to the invention facilitate their manufacture by stamping processes because the stamping edges are short compared to conventional lamellar bushings due to the contours and openings or slots. This enables reduced stamping forces and minimized stamping times. In this way, economical mass production is supported.

[0029] The invention is explained in more detail below with reference to an exemplary embodiment in conjunction with the figures. These show: Fig. 1 the perspective view of the shaft sleeve; Fig. 2 the side view of the shaft sleeve; Fig. 3 the perspective view of the helical pin; Fig. 4 the spatial view of the contact partner combination for an electrically conductive plug connection; Fig. 5 the three-dimensional view of the helical pin assembled with the shaft sleeve; Fig. 6 the perspective view of the shaft sleeve with its unfolded shape.

[0030] Figure 1 Figure 1 shows a perspective view of the shaft sleeve 30 with its largely linear axial extent and the corrugated structure realized in the circumferential direction. The shaft sleeve 30 has an opening OE, which in this embodiment has a largely linear axial extent and provides an open cross-section. The opening OE creates a high elastic deformation capacity in the radial direction, which is further enhanced by the corrugated structure.

[0031] One or more slots SH can be provided in the shaft sleeve 30, which are geometrically inclined or similar to a helix and further increase the elasticity properties of the shaft sleeve 30.

[0032] Figure 2 The figure includes a side view of the shaft sleeve 30 and shows both the open cross-section caused by the opening OE and the wave-like structure. The wave-like structure is formed by waves extending circumferentially and created by radii of curvature or arcuately curved areas. To achieve this wave-like structure, the adjacent radii of curvature or arcuately curved areas have alternating signs.

[0033] In addition to increasing the elastic deformability of the shaft sleeve 30, the wave-shaped areas are used to provide contact surfaces for the contact bushing 10 and the helical pin 20. For this purpose, the outwardly curved wave areas have a radius of curvature R1, so that the contact bushing 10 can be contacted, and the inwardly curved wave areas of the shaft sleeve 30 have a radius of curvature R2, so that the helical pin 20 can be contacted.

[0034] In the end region of the shaft sleeve 30 adjacent to the opening OE, the shaft sleeve 30 can be slightly rolled inwards; preferably, a radius of curvature R1 is provided here. This design offers the advantage that the shaft sleeve 30, with its sharp-edged ends, cannot become entangled in the contact bushing 10 during the assembly of the contact partners or during elastic deformations occurring in operation.

[0035] Figure 3Figure 1 illustrates the geometry and structure of the helical pin 20 in a perspective view. The helical pin 20 is primarily formed by a plug-in body, pin 21, which is optionally supplemented by a functional element 40. The plug-in body, pin 21, of the helical pin 20 has at least a portion of a slot SW that extends axially and is preferably inclined and helical. The slot SW and the resulting open cross-section allow temperature-induced deformation in the radial direction of the helical pin 20, so that a change in the normal contact force can be transmitted to the inner surface of the contact bushing 10 via the shaft sleeve 30.

[0036] The optional functional element 40 can complement the helical pin 20. The functional element 40 can extend in the opposite direction to the insertion direction and be designed as an extension of the connector body, pin 21. It can have a bore, tabs, or other geometries suitable for providing additional functions, such as a grip to assist handling when connecting the contact or connector partners, consisting of contact socket 10 and wave sleeve 30 and the helical pin 20, or for attaching a cable or conductor (possibly with shielding) by, for example, welding or crimping.

[0037] In the insertion direction, the helical pin 20 can have a chamfer or bevel at the end of the plug body, pin 21, which facilitates threading into the wave sleeve 30.

[0038] Figure 4The spatial representation of the contact partner combination 1 for an electrically conductive connector comprises a contact socket 10, a helical pin 20, and a shaft sleeve 30 arranged between the inner contact surface of the contact socket 10 and the outer contact surface of the helical pin 20. The temperature-induced deformation in the radial direction caused by the helical pin 20 alters the contact normal force and is effectively transmitted by the shaft sleeve 30 both to the inner contact surface of the contact socket 10 and limited to a maximum contact normal force value by elastic deformation. The geometric design of the shaft sleeve 30, in conjunction with a suitable material selection such as spring steel, allows the transmitted contact normal force to be very precisely limited to a maximum value.At the same time, the shaft sleeve 30 is able to compensate for angular deviations of the contact partners 10, 20 to each other and / or to dampen vibration loads that may occur or to reduce them through dynamic deformations.

[0039] Figure 5Figure 1 shows a three-dimensional view of the helical pin 20 assembled with the shaft sleeve 30. The opening OE of the shaft sleeve 30 in this embodiment is axially parallel, arranged circumferentially offset from the helical slot SW of the helical pin 20, and the shaft sleeve ends adjacent to the opening OE are slightly curled. This ensures that the opening OE and the slot SW do not interlock even if the shaft sleeve 30 should twist. The at least one slot SH of the shaft sleeve 30 has an oblique arrangement that differs from the slot SW of the helical pin 20, so that these structural elements also cannot interlock when they are partially aligned circumferentially. That is to say,, that the longitudinal extensions of the slot SW of the helix pin 20 and the at least one slot SH of the helix sleeve 30 and / or the opening OE of the helix sleeve 30 are not radially identical and therefore not congruent to each other.

[0040] As an alternative to the measures described to prevent the shaft sleeve 30 and the helix pin 20 from becoming entangled in the event of twisting relative to each other, the shaft sleeve 30 can, for example, prevent twisting by means of a locking lug engaging in the opening OE.

[0041] Figure 6Figure 1 shows a perspective view of the wave sleeve 30 with its development. The starting material, in the form of a flat piece with slots SH, has a very simple geometric shape and can be produced economically and for mass production, for example, by a stamping process. The wave-like structures can be incorporated and the cylindrical shape of the wave sleeve 30 created, for example, by cold or hot forming in the form of rolling. Reference symbol list

[0042] 1 contact partner combination for an electrically conductive plug connection 10 contact socket 20 Contact plug, helical pin 21 Plug body, pin 30 shaft sleeve 40 Functional element OE Opening (of the shaft sleeve) R1 Radius of curvature Bushing contact R2 Radius of curvature Pin contact SH Slot (shaft sleeve) SW Slot, helical slot (of the helical pin)

Claims

1. Contact partner combination (1) for an electrically conductive plug-in connection, comprising a contact socket (10) and a contact plug (20) corresponding to the contact socket and a shaft sleeve (30) arranged between the contact surfaces of the contact socket (10) and the contact plug (20), characterized in that the contact plug is in the form of a helical pin (20) with the property of deforming in the event of a change in temperature and this helical pin has a plug-in body in the form of a pin (21) in which a slot (SW) is made, so that a deformation in the radial direction induced by a change in temperature is assisted and the shaft sleeve (30) is designed both for forwarding the deformation of the helical pin (20) induced by a change in temperature as a change in contact normal force to the contact surface of the contact socket (10) and for limiting the magnitude of the contact normal force by an elastic deformation.

2. Contact partner combination (1) according to Claim 1, characterized in that the shaft sleeve (30) has a largely linear extent in the axial direction.

3. Contact partner combination (1) according to Claim 1, characterized in that the shaft sleeve (30) has a plurality of wave-shaped structures, formed by radii of curvature and / or arcuately curved regions, in the circumferential direction.

4. Contact partner combination (1) according to Claim 3, characterized in that the radii of curvature and / or arcuately curved regions are alternately curved radially inwards and radially outwards.

5. Contact partner combination (1) according to Claim 4, characterized in that the inwardly curved regions form contact areas with the contact areas of the helical pin (20) and have a radius of curvature R2.

6. Contact partner combination (1) according to Claim 4, characterized in that the outwardly curved regions form contact areas with the contact areas of the contact socket (10) and have a radius of curvature R1.

7. Contact partner combination (1) according to Claims 5 and 6, characterized in that the radii of curvature R1, R2 have different signs.

8. Contact partner combination (1) according to Claim 1, characterized in that the shaft sleeve (30) has at least one slot (SH).

9. Contact partner combination (1) according to Claim 1, characterized in that the shaft sleeve (30) has an opening (OE) at least in regions, so that a cross section which is open at least in regions is formed.

10. Contact partner combination (1) according to Claim 1, characterized in that the helical pin (20) is formed from a material with a high coefficient of thermal expansion and / or from a multi-layer material or a shape memory alloy with the property of carrying out a change in shape owing to a change in temperature.

11. Contact partner combination (1) according to Claim 1, characterized in that the slot (SW) extends obliquely and / or helically in the longitudinal direction.

12. Contact partner combination (1) according to Claims 1 and 8, characterized in that the slot (SW) and the at least one slot (SH) are not congruent to each other, so that interengagement of the shaft sleeve (30) with the helical pin (20) is prevented.

13. Contact partner combination (1) according to Claim 1, characterized in that the helical pin (20) has a functional element (40) at the axial end opposite to the plug-in direction of the helical pin (20).

14. Releasable plug-in connection for transmitting electrical energy, comprising at least one contact partner combination according to any of the preceding claims.

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