crimp connector for a mechanical and electrically conductive connection of an electrical contact to an electrical conductor and crimp connection of an electrical contact to an electrical conductor

Description

[0001] The invention relates to a crimp connector for mechanically and electrically connecting an electrical terminal contact to an electrical conductor having the features of the preamble of claim 1 and a crimp connection with the crimp connector.

[0002] The electrical connection contact is intended for an electrically conductive connection of the electrical conductor to, for example, a power source, or for electrically conductively connecting the electrical conductor to another electrical conductor. It can, for example, have a plug contact or an eyelet.

[0003] The electrical conductor is, for example, a cable and in particular a stranded wire.

[0004] Crimp connectors for the mechanical and electrically conductive connection of an electrical contact to an electrical conductor, such as a cable or wire, are known, for example, from so-called cable lugs. Cable lugs are stamped from a flat sheet of metal and bent into the desired shape. Extending from the actual cable lug, they have a projection that can also be considered the shaft of the cable lug. After stamping, tabs protrude from both sides of this projection. These tabs are bent around the electrical conductor to form a crimp clamp and are then crimped tightly. The tabs thus enclose the electrical conductor as a crimp clamp, clamping it between themselves and the projection of the cable lug. Patent application EP 2 846 404 A1 discloses a T-shaped crimp connector for grounding a cable in a substation of a power plant by connecting it to an earthing network laid in the ground.A crosshead of the T-shaped connector has U-shaped receptacles for the cable at both ends, which can be closed with sliding covers to form rings that enclose the cable, and in which the cable can be clamped by squeezing.

[0005] Patent application EP 2 495 813 A1 discloses a crimp connector comprising a flat, stamped sheet metal part with laterally projecting wings that are bent in a C-shape around a stripped end of a stranded wire, with the outer edges of the wings being pressed into the wire. Point-like protrusions on an inner side of the C are intended to improve the crimp connector's grip on the wire.

[0006] Patent application US 2006 / 0 160 419 A1 discloses a comparable crimp connector with a stamped sheet metal part having laterally projecting tabs that are bent into a sleeve-like shape around a stripped end of a stranded wire. This crimp connector also features a raised section between the tabs on the upper or inner surface of the stamped sheet metal part facing the wire, in order to improve the wire's retention.

[0007] The object of the invention is to propose a crimp connector and a crimp connection with low electrical contact resistance to an electrical conductor, which is suitable for high electrical currents of several hundred A, for example 800 A and more.

[0008] This problem is solved according to the invention by a crimp connector with the features of claim 1 and a crimp connection with the features of claim 9. The dependent claims relate to advantageous embodiments and further developments of the invention.

[0009] The crimp connector according to the invention, with the features of claim 1, is designed for mechanically and electrically conductive connection to an electrical conductor, in particular a stranded wire, i.e., an electrical conductor consisting of individual wires. The crimp connector has a connection zone for connecting to the electrical conductor and a crimp clamp which, when the connection is made, encloses the electrical conductor and crimps it tightly both within itself and to the connection zone of the crimp connector. This means that the crimp clamp, by crimping, i.e., by plastic deformation of the crimp clamp, clamps the electrical conductor within itself and thereby mechanically and electrically secures the electrical conductor to the connection zone of the crimp connector.The crimp clamp can, for example, be ring-shaped or have one or two tabs, tongues or the like, which are bent into the crimp clamp by plastic deformation.

[0010] According to the invention, the crimp connector has a groove-shaped recess in the connection zone in which the electrical conductor is arranged for connection and clamped with the crimp clamp.

[0011] The groove-shaped recess improves the mechanical hold of the electrical conductor on the crimp connector and, in particular, reduces electrical contact resistance between the crimp connector and the electrical conductor by molding the electrical conductor to the recess in the connection zone of the crimp connector when the electrical conductor is crimped with the crimp clamp, thereby improving the electrically conductive connection between the crimp connector and the electrical conductor.

[0012] The channel-shaped recess can, for example, have an angular, such as rectangular or trapezoidal, or a rounded, such as circular or elliptical, cross-section. A preferred embodiment of the invention provides a step-shaped recess with steps extending in a longitudinal direction. A step-shaped cross-section of the recess has proven advantageous with regard to a low electrical contact resistance between the crimp connector and the electrical conductor.

[0013] The invention provides that the crimp connector has stacked or layered, i.e., superimposed, sheets in the connection zone. One of the layered sheets, also referred to here as the base sheet, bridges the recess at one end. The base sheet, so to speak, forms the bottom of the recess. Sheets arranged on one side of the base sheet have recesses that laterally define the recess. To create the stepped shape of the recess, the recesses are narrower in sheets closer to the base sheet than in sheets further away, such that the recess widens in a stepped fashion with increasing distance from the base sheet. In principle, a single sheet with a recess on one side of the base sheet is sufficient, thus forming a single-step recess.Preferably, several layered sheets with recesses of varying widths are arranged on one side of the base sheet, whereby several sheets can have recesses of the same width to form a step. Alternatively, several sheets without recesses can be used as base sheets.

[0014] The crimp clamp of preferred embodiments of the invention is a component separate from the crimp connector, which encloses the connection zone of the crimp connector and, when the connection is made, the electrical conductor. The crimp clamp can thus be manufactured from a different material, for example, as unlaminated sheet metal and / or with a different thickness than the laminated sheets in the connection zone of the crimp connector. Designing the crimp clamp as a separate component allows for adaptation to its function without limitations imposed by the design of the connection zone.

[0015] A further development stipulates that the crimp clamp holds the layered sheets in their intended and stacked position relative to each other, with the recesses in the layered sheets forming the depression in the connection zone of the crimp connector. Once the crimp connection is established, the crimp clamp clamps the layered sheets together and against the electrical conductor.

[0016] For example, the layered sheets have openings through which the crimp clamp passes, the crimp clamp aligning the openings in the sheets and thereby holding the layered sheets in their intended position. Preferably, the openings in the layered sheets are provided on both sides of the recess so that the crimp clamp passing through the openings holds the layered sheets more securely against rotation.

[0017] In a preferred embodiment of the invention, the crimp terminal has a U-shaped clamp that completely encloses and clamps the electrical conductor on one side of the terminal contact. The crimp terminal is fixed to the terminal contact on both sides of the electrical conductor and completely encloses the conductor from one side to the opposite side. The crimp terminal clamps the conductor between itself and the terminal contact and secures the conductor in the recess in the terminal contact. Because the crimp terminal completely encloses the conductor in this embodiment, it cannot loosen by bending, thus improving the clamping of the conductor in the crimp terminal and at the terminal contact of the crimp connector according to the invention.

[0018] A further development of the invention provides that the crimp terminal has a projection formed into the electrical conductor on its inner side facing the conductor. This projection forms a recess in the conductor and extends from the inner side of the crimp terminal into this recess. This creates a positive fit between the crimp terminal and the conductor, preventing the conductor from being pulled out of the terminal. This positive fit, in addition to the clamping force of the terminal, provides additional retention of the conductor, thus improving the mechanical retention of the conductor both within the terminal and in the recess of the terminal contact of the crimp connector according to the invention.

[0019] The crimp connection according to the invention with the features of claim 9 has an electrical connection contact with a crimp connector of the type described above and an electrical conductor which is arranged in the recess in the connection zone of the crimp connector, enclosed by the crimp clamp and crimped firmly with the crimp clamp in the crimp clamp and in the recess in the connection zone of the crimp connector, i.e. mechanically fixed by a plastic deformation of the crimp clamp and electrically connected to the crimp connector and via the crimp connector electrically connected to the connection contact.

[0020] The connection contact features, for example, an electrical connector, such as a plug or socket as a counterpart to a plug, an electrical screw connector, or an eyelet for creating an electrically conductive screw connection. This list is not exhaustive. The connection contact of the crimp connector is designed for an electrically conductive connection of the electrical conductor to, for example, a power source or another electrical conductor.

[0021] The electrical conductor includes, for example, a cable and, in particular, a strand.

[0022] All features mentioned in the description and / or illustrated in the drawing can be implemented individually or in any combination in embodiments of the invention. Embodiments of the invention that do not include all, but only some, of the features of a claim, including an independent claim, are possible.

[0023] The invention is explained in more detail below with reference to an embodiment illustrated in the drawing. The drawing shows: Figure 1 is a perspective exploded view of a crimp connector according to the invention; Figure 2 is a sheet metal assembly of the crimp connector made of Figure 1 Figure 3 shows a perspective view of a crimp connection according to the invention with the crimp connector made of Figure 1 and 2 ; and Figure 4 the crimp connection made of Figure 3 in a perspective view looking at the opposite side, as in Figure 3 .

[0024] The crimp connector 1 according to the invention, as shown in the drawing, has an electrical connection contact 2 and is designed for mechanical and electrically conductive connection with an electrical conductor 3. In the exemplary embodiment, the electrical connection contact 2 is designed as a plug socket with a socket 4 for inserting or for mounting onto a mating contact (not shown), for example, a cylindrical one.

[0025] In the socket 4, the connecting contact 2 has a stack of coaxially stacked contact springs 5. In the exemplary embodiment, the contact springs 5 ​​are circular and open at one circumferential point. They have outwardly projecting outer projections 15 at opposite circumferential points – in the exemplary embodiment, a total of four – which bear against the inside of the socket 4 of the connecting contact 2. Inside, the contact springs 5 ​​have inner projections 16 at opposite circumferential points – in the exemplary embodiment, two – which project inwards and bear against the mating contact (not shown), for example, a cylindrical contact, with a radial preload when the mating contact is inserted into the socket 4 or into the contact springs 5 ​​in the socket 4 of the connecting contact 2. In the exemplary embodiment, the contact springs 5 ​​are stamped sheet metal parts, although other embodiments are possible according to the invention. Figure 1A contact spring 5 is shown above a cover plate 17 of the connecting contact 2 of the crimp connector 1 according to the invention, in order to show the shape of the contact springs 5.

[0026] Due to the radial preload with which the contact springs 5 ​​bear against the mating contact (not shown) when the mating contact is inserted into the socket 4 or into the contact springs 5 ​​of the terminal contact 2 of the crimp connector 1 according to the invention, the crimp connector 1 has good electrical contact with a low electrical contact resistance between the terminal contact 2 of the crimp connector 1 and the inserted mating contact (not shown).

[0027] To hold the stacked contact springs 5 ​​axially in the socket 4 of the connecting contact 2 of the crimp connector 1 according to the invention, cover plates 17 are arranged above and below on the contact area 7. These cover plates have a hole concentric with the socket 4 that covers the contact springs 5 ​​and thereby holds them axially in the socket 4. The diameter of the hole in the cover plates 17 is at least as large as the inner diameter of the contact springs 5 ​​such that the inner projections 16 of the contact springs 5 ​​protrude inwards beyond the hole in the cover plates 17. Figure 2 One of the two cover plates 17 is not shown so that the contact springs 5 ​​stacked in the socket 4 of the connection contact 2 are visible.

[0028] According to the invention, the crimp connector 1 comprises stamped, laser-cut, or otherwise manufactured sheet metal sheets 6, which are arranged in a layered, congruent arrangement, either lying on top of or abutting each other. Due to their layered arrangement, the sheet metal sheets 6 can also be considered stacked or as stamped packages.

[0029] Each of the metal sheets 6 has a contact area 7 with the insertion hole 4 and a connection zone 8. The contact areas 7 of the stacked metal sheets 6 form the connection contact 2 of the crimp connector 1 according to the invention.

[0030] In the connection zone 8, the sheets 6, with the exception of one or more base sheets 9, have a recess 10 – rectangular in the exemplary embodiment – ​​which is located one above the other and forms a channel-shaped depression 11 when the sheets 6 are stacked congruently on top of or against each other. As stated, one or more of the sheets 6 – in the exemplary embodiment, arbitrarily two of the sheets 6 – do not have a recess 10, but bridge the recesses 10 in the connection zones 8 of the other sheets 6.The sheets 6 without recess 10, also referred to here as base sheet(s) 9, are located on one side of the stacked sheets 6, i.e., the sheets 6 with the recesses 10 are stacked on one side of the sheet(s) 6 without recess 10, i.e., arranged on one side of the base sheets 9 in such a way that the base sheet(s) 9 limit the recess 11 formed by the recesses 10 of the other sheets 6 at a base of the recess 11, i.e., the base sheet(s) 9 form the base of the recess 11 formed by the recesses 10 in the other sheets 6 in the connection zone 8 of the crimp connector 1 according to the invention.

[0031] The recesses 10 in the sheets 6 have different widths; those recesses 10 in the sheets 6 that are closer to the base sheet(s) 9 are narrower than those recesses 10 in the sheets 6 that are farther away. Thus, the recesses 10 in the sheets 6 become wider with increasing distance from the base sheet(s) 9. This results in the recess 11 in the connection zone 8 of the crimp connector 1 according to the invention being stepped, with a stepped cross-section or longitudinal sides on both sides. To form the steps on both sides of the recess 11, two or more sheets 6 can have recesses 10 of the same width, thereby jointly forming a step. In the exemplary embodiment, the recesses 10 of all sheets 6 have different widths.

[0032] The width of the recesses 10 in the plates 6 of the crimp connector 1 according to the invention decreases with increasing distance from the base plate(s) 9, i.e., the step width of the steps transverse to the recess 11 (the depth of the "step") decreases with increasing distance from the base plate(s) 9, which in Figure 2 This is evident. An imaginary, curved line of the cross-section of the depression 11 along the sides of the depression 11, formed by the edges of the steps, is therefore not a straight line rising obliquely towards the bottom of the depression 11, but rather follows an arc. The cross-section of the stepped depression 11 is thus adapted to an electrical conductor 3 with a round, but not necessarily circular, cross-section.

[0033] The recess 11 preferably has a step-shaped cross-section; however, recesses with other cross-sections, for example square, rectangular or trapezoidal cross-sections or with circular or non-circular rounded cross-sections, are also possible (not shown).

[0034] In the exemplary embodiment, the crimp connector 1 according to the invention has two base plates 9 and six plates 6 with recesses 10 of different widths, which are arranged stacked on one side of the two base plates 9, wherein plates 6 with narrower recesses 10 are arranged closer to the base plate(s) 9 and plates 6 with wider recesses 10 are arranged further away from the base plate(s) 9.

[0035] The two cover plates 17 are arranged coaxially to the mounting hole 4 at the top and bottom of the stacked plates 6 in the contact area 7. In the exemplary embodiment, the two cover plates 17 and the plates 6, 9 are held together by four rivets arranged around the mounting hole 4. The plates 6, 9, 17 can also be held together in another way.

[0036] The crimp connector 1 according to the invention has a crimp clamp 12, which can be integral with the crimp connector 1, but in the exemplary embodiment is a component separate from the crimp connector 1 or from its plates 6, 9. The crimp clamp 12 is arranged in the connection zone 8 of the connection contact 2 or of the stacked plates 6, 9 that form the connection contact 2. In the exemplary embodiment, the crimp clamp 12 consists of a strip of sheet metal that is first bent into a U-shaped bracket (see Figure 1). Figure 1The legs of the U-shaped bracket forming the crimp clamp 12 are inserted through openings 13 in the layered sheets 6, 9 of the crimp connector 1. In the exemplary embodiment, the openings 13 are designed as slots on both sides of the recesses 10 in the sheets 6, 9, which form the recess 11 in the connection zone 8 of the crimp connector 1. The crimp clamp 12 inserted through the openings 13 in the sheets 6, 9 and the rivets hold the layered sheets 6, 9 in their congruent, stacked position relative to one another.

[0037] The crimp terminal 12 is arranged on the terminal contact 2 of the crimp connector 1 according to the invention such that a yoke of the U-shaped bracket forming the crimp terminal 12 encloses the electrical conductor 3 on one side opposite the recess 11 in the terminal contact 2, and legs of the crimp terminal 12 extend past the electrical conductor 3 on both sides and pass through the openings 13 in the plates 6, 9, and are bent over by 90° on one side of the plates 6, 9 opposite the electrical conductor 3 in order to connect the crimp terminal 12 to the terminal contact 2. The ends of the crimp terminal 12 bent over on the side of the base plates 9 are in Figure 4to be seen. Because the yoke of the crimp terminal 12 encloses the electrical conductor 3, the crimp terminal 12 encloses the electrical conductor 3 on the side of the connection contact 2, in which the recess 11 is located, in which the electrical conductor 3 lies with part of its circumference, continuously without interruption.

[0038] To produce a crimp connection 14 according to the invention, the electrical conductor 3 is arranged in the recess 11 in the connection zone 8 of the crimp connector 1 according to the invention and between the legs of the U-shaped crimp clamp 12, which are inserted through the slots forming the openings 13 on both sides of the recess 11. The electrical conductor 3 is, for example, a cable, in particular a stranded wire, the stripped end of which is arranged in the recess 11 between the legs of the crimp clamp 12. Subsequently, the crimp clamp 12 is pressed at its yoke towards the plates 6, whereby the electrical conductor 3 is clamped by the crimp clamp 12 into the recess 11 in the connection zone 8 of the crimp connector 1 and clamped between the recess 11 and the crimp clamp 12.

[0039] The ends of the legs of the crimp clamp 12 are bent over on the opposite side, i.e., on the side of the base plates 9, in such a way that the crimp clamp 12 is connected to the plates 6, 9 and clamps the electrical conductor in the recess 11.

[0040] To improve the mechanical retention of the electrical conductor 3 in its longitudinal direction within the crimp terminal 12, a groove is embossed into the yoke of the crimp terminal 12, which forms a recess 19 inside the yoke of the crimp terminal 12 and is formed there in the electrical conductor 12. Figure 1 The groove of the crimp terminal 12 can generally also be understood as a projection 20 in the crimp terminal 12, which is formed into the electrical conductor 3 and improves its mechanical hold in its longitudinal direction in the crimp terminal 12.

[0041] The stranded wire forming the electrical conductor 3 in the exemplary embodiment has a conductor cross-section without insulation of, for example, 125 mm² and a conductor diameter without insulation of, for example, 25–28 mm. A pressing force exerted perpendicular to the terminal contact 2 on the yoke of the crimp terminal 12 to clamp the electrical conductor 3 in the crimp terminal 12 and in the recess 11 in the connection zone 8 of the crimp connector 1 is, for example, 20 t (tons). The legs of the crimp terminal 12 are supported laterally from the outside during pressing to prevent them from bending outwards.

[0042] When the strand forming the electrical conductor 3 is crimped, the individual wires of the strand are formed against the steps on the sides of the recess 11 in the connection zone 8, thereby achieving, on the one hand, a mechanically tight connection of the electrical conductor 3 with the crimp connector 1 of the crimp connection 14 according to the invention and, on the other hand, an electrically conductive connection with low electrical contact resistance between the electrical conductor 3 and the crimp connector 1.

[0043] The crimp connector 1 or crimp connection 14 according to the invention is suitable for electrical currents of several hundred amperes, for example 800 A or more, and for connecting to or to electrical power sources with an electrical voltage of several hundred volts, for example 1,000 V or more. A possible or intended use of the crimp connector 1 or crimp connection 14 according to the invention is for connecting to or to a traction battery / accumulator of an electrically powered motor vehicle, in particular an electrically powered truck.

Claims

1. Crimp connector for mechanical and electrically conductive connection to an electrical conductor, wherein the crimp connector (1) comprises a connection zone (8) for the connection to the electrical conductor (3) and a crimp clamp (12) for enclosing and crimping the electrical conductor (3) in the connection zone (8), and wherein the connection zone (8) of the crimp connector (1) comprises a groove-shaped recess (11), in which the electrical conductor (3) is arranged for connection, characterized in that the connection zone (8) of the crimp connector (1) comprises layered metal sheets (6), wherein at least one base metal sheet (9) at a base of the recess (11) bridges the recess (11) and metal sheets (6) arranged in layers on one side of the base metal sheet (9) comprises cutouts (10) which laterally delimit the recess (11).

2. Crimp connector according to claim 1, characterized in that the groove-shaped recess (11) comprises step-shaped cheeks.

3. Crimp connector according to claim 1, characterized in that the cutouts (10) in the metal sheets (6) arranged in layers on the one side of the base metal sheet (9) are wider with increasing distance from the base metal sheet (9).

4. Crimp connector according to one or more of the preceding claims, characterized in that the crimp clamp (12) is a separate component of the crimp connector (1) which encloses the connection zone (8) and the electrical conductor (3).

5. Crimp connector according to claims 1 and 4, characterized in that the crimp clamp (12) holds the layered metal sheets (6, 9) in their layered positions with respect to one another.

6. Crimp connector according to claim 5, characterized in that the layered metal sheets (6) comprise apertures (13) through which the crimp clamp (12) passes.

7. Crimp connector according to one or more of claims 4 to 6, characterized in that the crimp clamp (12) continuously encloses the electrical conductor (3) on the side of the connection zone (8) in which the groove-shaped recess (11) is located and is fixed to the connection zone (8) on both sides of the electrical conductor (3).

8. Crimp connector according to one or more of the preceding claims, characterized in that the crimp clamp (12) comprises a protrusion (20), formed into the electrical conductor (3) on an inner side facing the electrical conductor (3).

9. Crimp connection, comprising an electrical conductor (3) and an electrical connection contact (2), which comprises a crimp connector (1) according to one or more of the preceding claims, which connects the electrical conductor (3) mechanically and electrically conductively to the electrical connection contact (2), characterized in that the electrical conductor (3) is arranged in the recess (11) in the connection zone (8) of the crimp connector (1) and is enclosed by the crimp clamp (12) and is crimped in the recess (11).

10. Crimp connection according to claim 9, characterized in that the crimp clamp (12) is a separate component of the crimp connector (1) which encloses the connection zone (8) and the electrical conductor (3), clamps the electrical conductor (3) together with the connection zone (8) of the crimp connector (1) and clamps the electrical conductor (3) in the recess (11) in the connection zone (8) of the crimp connector (1).

11. Crimp connection according to claim 9 or 10, characterized in that the electrical conductor (3) comprises a stranded wire.