Connection device for an electrical conductor, and contacting unit
Patent Information
- Application Number
- EP2024700987
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-02-08
- Filing Date
- 2024-01-16
- Publication Date
- 2025-12-17
AI Technical Summary
Existing connection devices struggle to efficiently contact high-frequency electrical conductors with medium-frequency currents, leading to increased copper losses due to the skin and proximity effects, as traditional crimping or soldering methods are impractical for stranded conductors with enamel insulation.
A connection device with a housing and clamping jaws, utilizing spring elements to securely hold and clamp the conductor between two electrically connected contact surfaces, increasing the contact area and reducing resistance, and optionally using conductive films for enhanced current flow.
The solution significantly reduces contact resistance and losses by providing a large, force-fitting contact area and improved current path, making it suitable for high-frequency applications without the need for soldering or removing insulation.
Smart Images
Figure EP2024050924_15082024_PF_FP
Abstract
Description
[0001] Connection device for an electrical conductor and contacting unit
[0002] Description:
[0003] The invention relates to a connecting device for an electrical conductor, comprising a housing with a receiving area for receiving an end area of the electrical conductor. The invention also relates to a contacting unit, in particular for a system for contactless energy transmission, comprising a connecting device according to the invention and an electrical conductor.
[0004] In the field of electronic circuit technology, especially in power electronics, converters that generate medium-frequency alternating voltages and currents in the range of 10 kHz to 500 kHz are increasingly being used. The advantage is that magnetic components such as chokes and transformers can be designed significantly smaller as the frequency increases, thus saving space and weight.
[0005] DE 102021 005 981 A1 discloses a system for contactless energy transmission. The system comprises a power source that feeds a primary current with a fundamental frequency between 25 kHz and 100 kHz into a primary conductor. Energy is transmitted inductively from the primary conductor to a transmitter head of a mobile device.
[0006] DE10 2016 010 951 A1 discloses a device comprising a busbar and a movably mounted clamping element. A contact plate is provided for connecting an electrical conductor to the busbar.
[0007] WO 2022 / 223608 A1 discloses a prefabricated electrical cable for an electrical connector. The cable and the connector have locking means for locking.
[0008] However, when conducting medium-frequency currents, significant effects such as the skin effect and the proximity effect occur, causing the current to be distributed less evenly across the entire conductor cross-section. To reduce these effects, which lead to higher copper losses in the conductor, HF stranded wires, for example, are used as current-carrying conductors. In such a stranded wire, many thin, enamel-insulated individual wires with a diameter between 0.05 mm and 0.2 mm are stranded into a bundle.
[0009] This can significantly reduce current displacement effects.
[0010] Connecting such a stranded wire is relatively complex. Simple crimping or squeezing is not possible due to the enamel-insulated individual wires. The enamel layer must first be removed in a soldering process. The conductor bundle is then directly soldered, soldered into a cable lug for screw connection, or contacted using a spring-loaded terminal. For thick conductor bundles that carry high currents, contacting with a spring-loaded terminal does not produce satisfactorily low contact resistance. Direct soldering is often impractical, and soldering into a cable lug involves a relatively large amount of effort.
[0011] The invention is based on the object of developing a connection device for an electrical conductor and a contacting unit, in particular for a system for contactless energy transmission.
[0012] The object is achieved according to the invention by a connecting device for an electrical conductor having the features specified in claim 1. Advantageous embodiments and further developments are the subject of the subclaims. The object is also achieved according to the invention by a contacting unit having the features specified in claim 10. Advantageous embodiments and further developments are the subject of the subclaims.
[0013] A connection device according to the invention for an electrical conductor comprises a housing with a receiving area for receiving an end portion of the electrical conductor, at least one clamping jaw for non-positively holding the end portion of the electrical conductor received in the receiving area, and at least one spring element that presses the at least one clamping jaw toward the end portion of the electrical conductor received in the receiving area. The receiving area is arranged within the housing.The connecting device has a first contact surface and a second contact surface, which are arranged such that the end region of the electrical conductor received in the receiving region can be or is clamped in a force-fitting manner between the first contact surface and the second contact surface by the spring element and the at least one clamping jaw, and that the end region of the electrical conductor clamped in a force-fitting manner between the first contact surface and the second contact surface bears in contact with the first contact surface and the second contact surface.
[0014] The connecting device according to the invention has a relatively large contact area between the electrical conductor and the contact surfaces. This advantageously reduces the contact resistance. This also reduces contact losses.
[0015] According to an advantageous embodiment of the invention, the first contact surface and the second contact surface are electrically connected to one another even in the absence of an electrical conductor to be connected. Both contact surfaces are electrically connected to a common contact point. Thus, a partial current flows from the clamped end region of the electrical conductor via the first contact surface to the contact point, and another partial current flows from the clamped end region of the electrical conductor via the second contact surface to the contact point. At the contact point, the partial currents recombine to form a total current. The contact surface between the electrical conductor and the connecting device is thereby advantageously enlarged, and the contact resistance is further reduced. This also further reduces contact losses.
[0016] According to an advantageous embodiment of the invention, the first contact surface and the second contact surface are arranged opposite one another and movable relative to one another. The spring element presses the first contact surface toward the second contact surface via the at least one clamping jaw. As a result, the end region of the electrical conductor received in the receiving area is clamped between the first contact surface and the second contact surface in a force-fitting manner.
[0017] According to an advantageous embodiment of the invention, the first contact surface is formed by an electrically conductive foil. The foil extends from the first contact surface to the contact point. The partial current thus flows through the foil to the contact point.
[0018] According to an advantageous embodiment of the invention, the film which forms the first contact surface rests against the at least one clamping jaw.
[0019] According to an advantageous embodiment of the invention, the second contact surface is formed by an electrically conductive foil, in particular by another electrically conductive foil, which rests against the housing. The foil extends from the second contact surface to the contact point. The partial current thus flows through the foil to the contact point.
[0020] According to an advantageous embodiment of the invention, the connecting device comprises a first clamping jaw and a second clamping jaw, and the at least one spring element presses the first clamping jaw and the second clamping jaw toward each other. The clamping jaws are arranged on both sides of the end region of the electrical conductor, and each of the clamping jaws presses one of the contact surfaces toward the end region of the electrical conductor.
[0021] According to an advantageous embodiment of the invention, the first contact surface is formed by an electrically conductive film which rests on the first clamping jaw, and the second contact surface is formed by an electrically conductive film, in particular by a further electrically conductive film, which rests on the second clamping jaw.
[0022] According to an advantageous embodiment of the invention, the receiving area has a rectangular cross-section.
[0023] A contacting unit according to the invention, in particular for a system for contactless energy transmission, comprises a connecting device according to the invention and an electrical conductor, which is designed as a stranded wire and comprises a plurality of parallel individual wires. An end region of the electrical conductor is received in the receiving region, and the end region of the electrical conductor is clamped between the first contact surface and the second contact surface in a force-fitting manner. The end region of the electrical conductor is in contact with the first contact surface and the second contact surface.
[0024] The contacting unit according to the invention has a relatively large contact area between the electrical conductor and the contact surfaces of the connecting device. This advantageously reduces the contact resistance. This also reduces contact losses.
[0025] According to an advantageous embodiment of the invention, the end region of the electrical conductor has a rectangular cross-section, and the individual wires are soldered together in the end region. The rectangular cross-section results in a significantly larger contact area between the electrical conductor and the connecting device. This further reduces the contact resistance and contact losses.
[0026] According to an advantageous embodiment of the invention, the rectangular cross-section has two long sides and two short sides. One long side is at least twice as long, preferably four times as long, as a short side. The long sides each rest on one of the contact surfaces. This further increases the contact area between the electrical conductor and the connecting device. This further reduces the contact resistance and contact losses.
[0027] The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.
[0028] The invention will now be explained in more detail with reference to the accompanying drawings. The invention is not limited to the exemplary embodiments shown in the drawings. The drawings only represent the subject matter of the invention schematically. They show:
[0029] Figure 1: a perspective view of a contacting unit according to a first embodiment,
[0030] Figure 2: a sectional view of the contacting unit according to the first embodiment,
[0031] Figure 3: a perspective view of a contacting unit according to a second embodiment and
[0032] Figure 4: a sectional view of the contacting unit according to the second embodiment.
[0033] Figure 1 shows a perspective view of a contacting unit according to a first exemplary embodiment. The contacting unit comprises an electrical conductor 20 and a connecting device 10 for connecting the electrical conductor 20. The connecting device 10 comprises a receiving area for receiving an end area 24 of the electrical conductor 20. The end area 24 of the electrical conductor 20 is received in the receiving area.
[0034] The electrical conductor 20 is designed as a stranded wire and comprises a plurality of parallel individual wires. The individual wires are made of an electrically conductive material, in particular copper, and are each circularly cylindrical. The individual wires of the conductor 20 are each coated with an electrically insulating layer of varnish. An insulation 22 coaxially surrounds the conductor 20.
[0035] In the end region 24 of the conductor 20, the lacquer layers are removed from the individual wires. In the end region 24, the individual wires are thus free of the electrically insulating lacquer layer.
[0036] The individual wires are soldered together in the end region 24. The end region 24 of the electrical conductor 20 has a rectangular cross-section. The contouring takes place while the conductor 20 is still hot and malleable, directly after tinning. The rectangular cross-section has two long sides and two short sides. One long side is at least twice as long, in this case approximately four times as long, as a short side. Figure 2 shows a sectional view of the contacting unit according to the first exemplary embodiment. The connection device 10 of the contacting unit comprises a housing 30 which is fastened to a circuit board 40. The housing 30 has a plurality of pins which are soldered or pressed to the circuit board 40.
[0037] The receiving area for receiving the end region 24 of the electrical conductor 20 is arranged within the housing 30. The receiving area has a rectangular cross-section.
[0038] The connecting device 10 has a first contact surface and a second contact surface. The first contact surface is formed by an electrically conductive foil 37. The second contact surface is also formed by an electrically conductive foil 37. In the present case, the first contact surface and the second contact surface are formed by a common foil 37, which is laid accordingly. The foil 37 is soldered at two points to a conductor track applied to the circuit board 40. Thus, the first contact surface and the second contact surface are electrically connected to one another even in the absence of an electrical conductor 20 to be connected.
[0039] The connecting device 10 has a clamping jaw 31 and a spring element 35. The spring element 35 is designed as a spiral spring and is supported on the housing 30. The spring element 35 presses the clamping jaw 31 toward the end region 24 of the electrical conductor 20 received in the receiving region. The receiving region is located between the clamping jaw 31 and the housing 30.
[0040] The film 37, which forms the first contact surface, is located between the clamping jaw 31 and the end region 24 of the electrical conductor 20. The film 37 rests against the clamping jaw 31.
[0041] The film 37, which forms the second contact surface, is located between the housing 30 and the end region 24 of the electrical conductor 20. The film 37 rests against the housing 30.
[0042] The first contact surface, formed as a foil 37, and the second contact surface, formed as a foil 37, are arranged opposite one another and movable relative to one another. The spring element 35 presses the first contact surface toward the second contact surface via the clamping jaw 31.
[0043] The long sides of the cross-section of the end region 24 of the electrical conductor 20 each rest against one of the contact surfaces. The end region 24 of the electrical conductor 20 thus contacts the first contact surface and the second contact surface. The end region 24 of the electrical conductor 20 is clamped between the first contact surface and the second contact surface in a force-fitting manner.
[0044] The connecting device 10 has a clamping plate 47. The clamping plate 47 comprises a pin which passes through the housing 30 and is fastened to the clamping jaw 31. By pulling the clamping plate 47 with the pin in the direction away from the housing 30, the clamping jaw 31 is moved away from the end region 24 of the electrical conductor 20. In the process, the spring element 35 is tensioned, and the first contact surface moves away from the second contact surface. The clamping jaw 31 can thus be moved by means of the clamping plate 47 against a spring force of the spring element 35 in the direction away from the end region 24 of the electrical conductor 20 received in the receiving region.
[0045] Figure 3 shows a perspective view of a contacting unit according to a second exemplary embodiment. The contacting unit comprises an electrical conductor 20 and a connecting device 10 for connecting the electrical conductor 20. The connecting device 10 comprises a receiving area for receiving an end region 24 of the electrical conductor 20. The end region 24 of the electrical conductor 20 is received in the receiving area. The electrical conductor 20 is configured identically to the electrical conductor 20 according to the first exemplary embodiment.
[0046] Figure 4 shows a sectional view of the contacting unit according to the second embodiment. The connection device 10 of the contacting unit comprises a housing 30, which is mounted on a circuit board 40. The housing 30 has a plurality of pins, which are soldered or pressed to the circuit board 40.
[0047] The receiving area for receiving the end region 24 of the electrical conductor 20 is arranged within the housing 30. The receiving area has a rectangular cross-section. The connecting device 10 has a first contact surface and a second contact surface. The first contact surface is formed by an electrically conductive film 37. The second contact surface is also formed by an electrically conductive film 37. In the present case, the first contact surface and the second contact surface are formed by a common film 37, which is laid accordingly. The film 37 is soldered at two points to a conductor track applied to the circuit board 40. Thus, the first contact surface and the second contact surface are electrically connected to one another even in the absence of an electrical conductor 20 to be connected.
[0048] The connecting device 10 has a first clamping jaw 31, a second clamping jaw 32, and a spring element 35. The spring element 35 is in the form of a bracket that spans the clamping jaws 31, 32 and is supported on the first clamping jaw 31 and the second clamping jaw 32. The receiving area is located between the clamping jaws 31, 32.
[0049] The spring element 35 presses the first clamping jaw 31 and the second clamping jaw 32 towards each other and thus in the direction of the end region 24 of the electrical conductor 20 received in the receiving region.
[0050] The film 37, which forms the first contact surface, is located between the first clamping jaw 31 and the end region 24 of the electrical conductor 20. The film 37 rests against the first clamping jaw 31.
[0051] The film 37, which forms the second contact surface, is located between the second clamping jaw 32 and the end region 24 of the electrical conductor 20. The film 37 rests against the second clamping jaw 32.
[0052] The first contact surface, formed as a film 37, and the second contact surface, formed as a film 37, are arranged opposite one another and movable relative to one another. The spring element 35 presses the first contact surface toward the second contact surface via the first clamping jaw 31. The spring element 35 also presses the second contact surface toward the first contact surface via the second clamping jaw 32.
[0053] The long sides of the cross-section of the end region 24 of the electrical conductor 20 each rest against one of the contact surfaces. The end region 24 of the electrical conductor 20 thus rests in contact with the first contact surface and the second contact surface. The end region
[0054] 24 of the electrical conductor 20 is clamped between the first contact surface and the second contact surface.
[0055] List of reference symbols
[0056] 10 connection device 20 conductors
[0057] 22 Isolation
[0058] 24 End area
[0059] 30 housings
[0060] 31 first clamping jaw 32 second clamping jaw
[0061] 35 spring element
[0062] 37 Slide
[0063] 40 boards
[0064] 47 clamping plate
Claims
Patent claims:
1. A connecting device (10) for an electrical conductor (20), comprising a housing (30) with a receiving area for receiving an end area (24) of the electrical conductor (20), at least one clamping jaw (31, 32) for non-positively holding the end area (24) of the electrical conductor (20) received in the receiving area, and at least one spring element (35) which presses the at least one clamping jaw (31, 32) in the direction of the end area (24) of the electrical conductor (20) received in the receiving area, characterized in that the receiving area is arranged within the housing (30), and in that the connecting device (10) has a first contact surface and a second contact surface which are arranged such that the end area (24) of the electrical conductor (20) received in the receiving area is gripped by the spring element (35) and the at least one clamping jaw (31,32) can be clamped non-positively between the first contact surface and the second contact surface, and that the end region (24) of the electrical conductor (20) clamped non-positively between the first contact surface and the second contact surface bears against the first contact surface and the second contact surface.
2. Connecting device (10) according to claim 1, characterized in that the first contact surface and the second contact surface are electrically connected to one another even in the absence of an electrical conductor (20) to be connected.
3. Connecting device (10) according to one of the preceding claims, characterized in that the first contact surface and the second contact surface are arranged opposite one another and are movable relative to one another, and in that the spring element (35) presses the first contact surface in the direction of the second contact surface via the at least one clamping jaw (31, 32).
4. Connecting device (10) according to one of the preceding claims, characterized in that the first contact surface is formed by an electrically conductive foil (37).
5. Connecting device (10) according to claim 4, characterized in that the film (37) which forms the first contact surface rests against the at least one clamping jaw (31, 32).
6. Connecting device (10) according to one of the preceding claims, characterized in that the second contact surface is formed by an electrically conductive film (37) which rests against the housing (30).
7. Connecting device (10) according to one of claims 1 to 5, characterized in that the connecting device (10) has a first clamping jaw (31) and a second clamping jaw (32), and that the at least one spring element (35) presses the first clamping jaw (31) and the second clamping jaw (32) towards one another.
8. Connecting device (10) according to claim 7, characterized in that the first contact surface is formed by an electrically conductive film (37) which bears against the first clamping jaw (31), and that the second contact surface is formed by an electrically conductive film (37) which bears against the second clamping jaw (32).
9. Connecting device (10) according to one of the preceding claims, characterized in that the receiving area has a rectangular cross-section.
10. Contacting unit, in particular for a system for contactless energy transmission, comprising a connecting device (10) according to one of the preceding claims and an electrical conductor (20) which is designed as a stranded wire and comprises a plurality of parallel individual wires, wherein an end region (24) of the electrical conductor (20) is received in the receiving region and is clamped force-fittingly between the first contact surface and the second contact surface, and bears contactingly against the first contact surface and the second contact surface.
11. Contacting unit according to claim 10, characterized in that the end region (24) of the electrical conductor (20) has a rectangular cross-section, and that the individual wires in the end region (24) are soldered to one another.
12. Contacting unit according to claim 11, characterized in that the rectangular cross-section has two long sides and two short sides, and that one long side is at least twice as long, preferably four times as long, as a short side, and that the long sides each bear against one of the contact surfaces.