Cable connection unit for a junction box

Description

[0001] The invention relates to a cable connection unit according to the preamble of independent claim 1. The invention further relates to a system comprising a junction box and such a cable connection unit and a method for connecting the cable connection unit to the junction box.

[0002] These cable connection units are used for the electrical contact of junction boxes. Such junction boxes are used particularly in building installations and can be equipped with electronic controls, especially for actuators in ventilation systems. State of the art

[0003] EP 2 230 728 A1 (DE 10 2009 001 656 A1) discloses a multi-core cable, an electrical appliance, and a method for connecting a multi-core cable to an electrical appliance. The multi-core electrical cable has a fastening device with at least one opening and a surface. The multi-core cable further comprises several insulated single conductors attached to the surface of the fastening device, which run over the at least one opening.

[0004] DE 10 2008 021 868 A1 discloses an electrical connector with which a flexible wire or a multi-core cable, which is provided with at least one electrical conductor, is connected to a counterpart, wherein the wire or cable end to be connected is inseparably connected to at least one mechanical part of the connector and wherein the connector is designed such that the conductor(s) located at the end of the wire or cable is electrically contacted by means of a contact arranged on the counterpart when it is mounted to the assembly or socket and the wire or cable is thereby electrically and mechanically connected to the assembly or the socket together with the connector.

[0005] German patent DE 10 2004 007 525 A1 discloses a junction box for retrofitting to a live power line, consisting of two housing halves. The wall-mounted housing half contains centering devices for the insulated individual conductors of the power cable. The other housing half is equipped with sockets and contains inside a flexibly guided set of insulated insulation displacement contacts (IDCs). With the housing closed, the IDCs can be connected to the individual conductors from the outside using a tool. As long as the electrical connection is not established, a locking slide prevents plugs from being inserted into the junction box, thus ensuring that the IDCs are connected in a de-energized state. Therefore, an IP54 protection rating for the junction box is sufficient for the connection process and also during subsequent operation.

[0006] EP 0734095 A1 shows an electrical connector assembly in the form of an extension plug and a mating connector. The extension plug of the connector assembly is designed as a cable termination that is completely closed in line with the cable end.

[0007] DE 10 2020 114 330 A1 shows a junction box to which electrical conductors of a cable can be connected without tools using a so-called terminal block.

[0008] However, the individual conductor connections are not sealed in this solution. Moisture can penetrate here and potentially damage any electronics implemented in the junction box.

[0009] Therefore, junction boxes are often equipped with connector sockets, as shown in DE 10 2012 014 519 B3. However, such a design is expensive. Furthermore, cables must be pre-assembled with connectors, which is very time-consuming.

[0010] The German Patent and Trade Mark Office has searched the following prior art in the priority application for the present application: DE 10 2012 014 519 B3, DE 10 2004 007 525 A1, DE 10 2020 114 330 A1, DE 20 2005 019 522 U1 and DE 11 2012 003 826 T5. Task

[0011] The object of the invention is to propose a simple and cost-effective cable connection unit for a junction box. The installation of the junction box should be possible without tools and in a time-saving manner.

[0012] The problem is solved by the subject matter of the independent claims.

[0013] Advantageous embodiments of the invention are specified in the dependent claims and the following description.

[0014] The cable connection unit according to the invention is designed for connection to, or electrical contact with, a junction box. The junction box typically comprises electronics, in particular control electronics for actuators of ventilation systems. For this purpose, the junction box has a circuit board, protected by the housing of the junction box, which is electrically contacted via the cable connection unit.

[0015] The cable connection unit consists of a cable with at least two, but preferably at least four, electrical conductors enclosed by a cable sheath. Each individual conductor is also enclosed by an insulating sheath. This is also referred to as a multi-core cable. The conductors are preferably solid conductors and not stranded conductors. However, electrical conductors with more than four conductors can also be used.

[0016] The cable termination unit features a cable seal that radially surrounds the cable sheath. The cable seal is essentially cylindrical and encloses the cable sheath. It has a torus-like shape. Advantageously, the cable seal is a one-piece injection-molded part, which is attached to the cable sheath using an injection molding process. The cable seal provides a sealing function while simultaneously offering strain relief for the connected cable.

[0017] The cable termination unit features a cable manager designed to hold and secure the four electrical conductors of the cable. Within the cable manager, the four conductors lie side-by-side in a single plane. They are spaced sufficiently apart to allow contact via suitable insulation displacement connectors (IDCs). IDCs have a terminal at one end for electrically connecting the conductors to be joined. At the other end, the IDCs consist, for example, of a contact pin that makes electrical contact with a conductor on a printed circuit board.

[0018] In insulation displacement termination (IDT) contacting involves pressing the electrical conductors between two metallic cutting edges, thereby penetrating the conductor's insulation and establishing electrical contact between the conductor and the IDT. IDTs are known, for example, from DE 11 2012 003 826 T5 and are therefore not described further below.

[0019] In the cable manager, the electrical conductors are spaced apart and fanned out so that they can be pressed into an insulation displacement terminal (IDT) array. This process is described in more detail below. An IDT array is defined as a group of two or more IDT contacts arranged in a connection area.

[0020] Preferably, the cable manager is a one-piece injection-molded part that is attached to or molded onto the electrical conductors using an injection molding process. This pre-assembly of the cable manager ensures that the electrical conductors are reliably arranged in their correct sequence, thus reducing the potential for installation errors.

[0021] Alternatively, the cable manager is available in two parts, with the two parts locking together using a locking mechanism. The conductors are first manually inserted into the recesses of the first part. The locking mechanism with the second part then secures the inserted conductors in place. The individual recesses can be color-coded to correspond to the colors of the conductor insulation, thus simplifying the assembly of the cable manager.

[0022] Preferably, the cable manager has two contact openings, each essentially rectangular in shape. These contact openings are designed for subsequent insulation displacement connection (IDC) terminals.

[0023] Advantageously, the contact openings – viewed in the direction of insertion – are arranged one behind the other and offset from each other. This creates a so-called polarization, which prevents incorrect insertion or contact of the cable manager.

[0024] In an advantageous embodiment of the invention, the cable has a cable manager and a cable seal on both ends. This makes the cable connection unit suitable for tool-free electrical connection of two junction boxes.

[0025] Preferably, the cable should be no longer than three meters. This length has proven sufficient for building installations. The cables do not need to be manually shortened, which reduces the overall installation time.

[0026] The system according to the invention consists of a junction box and a cable connection unit described above. The junction box preferably includes control electronics for an actuator, which is particularly intended for ventilation control of the building.

[0027] The junction box has at least one recess for the cable connection unit, into which the cable seal and cable manager can each be inserted. The components can be pre-locked slightly here to simplify the installation process.

[0028] According to the invention, the receiving area of ​​the junction box has insulation displacement contacts (IDCs). Two IDCs are assigned to each contact opening of the cable connection unit. Advantageously, the junction box has a hinged cover. In this case, the cover has a dual function. On the one hand, it protects the junction box from the ingress of substances such as dust and water. On the other hand, the individual conductors can be pressed into the IDCs of the IDC contacts via the cover for electrical contact. The cover provides sufficient leverage for this purpose, enabling tool-free and effortless installation of the junction box.

[0029] According to the invention, the cable manager has test openings. Each test opening is assigned to an electrical conductor. The individual conductors are accessible via the test openings, even if they are already electrically connected to the junction box.

[0030] The system according to the invention includes a test device with which the correct electrical contact between the respective insulation displacement connector and the associated electrical conductor can be verified. For this purpose, the test device has contact pins that can each be inserted into a test opening of the cable manager.

[0031] The contact pins pierce the conductor, establishing an electrical connection. Integrated test electronics verify the correct electrical contact of each individual conductor and thus the entire junction box. The contact pins of the test device can then be easily removed, leaving virtually no residue. The small hole in the conductor's sheath closes automatically due to the material's self-clinging force and is irrelevant to the system's further operation.

[0032] Once the junction box has been attached to the designated location, for example a housing wall, the electrical installation procedure proceeds as follows: First, the cable seal and cable manager are inserted into a connection area of ​​the junction box. Then, the cable manager is pressed down using the test device, which pushes the electrical conductors of the cable into an insulation displacement connector (IDC) within the connection area, thus making electrical contact. A correct electrical installation can then be verified using the test device described above.

[0033] Preferably, a first cable end is connected to a first junction box as described above, and a second end of the cable is connected analogously to a second junction box. With a junction box and a cable connection unit according to the invention, building installations can be carried out quickly and efficiently.

[0034] The connection unit can have cable managers on both sides, allowing two adjacent connection boxes to be electrically connected via a single connection unit. Each connection box can have multiple contact points, for example, two contact points, for connection units. Example of implementation

[0035] An embodiment of the invention is shown in the drawings and is explained in more detail below. The drawings show: Fig. 1 a perspective view of two cable connection units and an associated junction box according to the invention, Fig. 2 a perspective view of a cable with free electrical conductors in the end region and a cable seal molded in front of it, Fig. 3 a perspective view of a cable with a cable manager, Fig. 4 a perspective view of a printed circuit board with a cable connection unit, Fig. 5 a perspective view of a printed circuit board connector, Fig. 6 a perspective view of a two-part cable manager in an unlatched state, Fig. 7 a perspective view of a two-part cable manager in a latched state, Fig. 8 a perspective view of a further embodiment of a two-part cable manager with an integrally molded cable seal in an unlatched state, and Fig.Fig. 9 A perspective view of a two-part cable manager according to the invention with an integrated cable seal in a locked position. Fig. 10 A schematic representation of a method for connecting a cable connection unit. Fig. 11 A perspective view of a test device.

[0036] The figures contain simplified, schematic representations. In some cases, identical reference symbols are used for elements that are the same but may not be identical. Different views of the same elements may be scaled differently. Indications such as left and right refer to the perspective of the respective figure.

[0037] In Figure 1Two variants of cable connection units are shown. The cable connection unit consists of a cable 4 at one end of which the electrical conductors 5 have been stripped from the cable sheath. According to the invention, a cable with at least two conductors is used. However, more than two conductors, for example six conductors 5, are also possible, as shown for example in Figure 8 shown, be present.

[0038] A molded-on cable seal 3 is provided in front of the exposed conductors 5. The individual conductors 5 are fanned out and fixed in a cable manager 2. The cable manager 2 has two contact openings 6 arranged one behind the other, but offset from each other parallel to the insertion direction SR.

[0039] The junction box 10 is in Figure 1 shown in its open state. The junction box 10 has a connection area 11, 11' which is in Figure 1The connection area 11, 11' is marked or highlighted by a dashed rectangle. A printed circuit board connector 12 is located in the connection area 11, 11'. The printed circuit board connector 12 has insulation displacement contacts with contact pins 9 for the printed circuit board 17 and insulation displacement terminals 14 for the electrical conductors 5. A receptacle AN, into which the cable seal 3 can be positively inserted, is also located in the connection area 11, 11'. The junction box 10 has a cover 15, which, when closed, has recesses 16 for the cable 4. The cover 15 can be screwed to the housing of the junction box 10 using screws 7.

[0040] The end section of a cable 4, freed from its cable sheath, is in Figure 2This is a four-core cable with four electrical conductors, each with an insulating sheath of a different color. The colors are standardized worldwide. For example, a green-yellow color marking indicates earth potential. The conductors are connected as shown in Figure 2 shown fanned out. These can then, for example, be placed in an injection mold and fitted with a cable manager 2, 2' in an injection molding process, as is the case, for example, in Figure 3 shown. Alternatively, two-part cable managers 2", 2‴ can be used, as shown in the Figure 6 and 8 are shown.

[0041] The junction box 10 has a circuit board 17 with control electronics (not shown). The circuit board 17 is shown schematically in Figure 4The circuit board connector 12 is plugged into circuit board 17 using contact pins 9. The contact pins 9 are each electrically connected to conductors on circuit board 17. The cable connection area of ​​the circuit board connector 12 is formed by the insulation displacement contacts 14.

[0042] When the cable connection unit 1 is positioned or inserted precisely into the connection area 11 of the junction box 10, the cover 15 of the junction box 10 is closed. Inside the cover, ribs 26 are molded. These ribs connect the individual conductors 5 of the cable 4 to the corresponding insulation displacement connectors 14 of the circuit board connector 12. Figure 5 ) pressed in.

[0043] In the Figures 6 and 7A first two-part variant of a cable manager 2" according to the invention is shown. The two parts 2a", 2b" can be locked together using locking arms 8 of one part 2b" and corresponding recesses 18 of the other part 2a". The individual conductors 5 are first inserted into one of the two parts 2a", 2b" in a fanned-out position.

[0044] The Figures 8 and 9 Figure 2 shows another two-part variant of a cable manager 2‴. Here, the two parts 2a‴ and 2b‴ are snapped together using studs 20 and corresponding stud openings 21. The electrical conductors 5 are first inserted into designated conductor holders 19. The variant of the cable manager 2‴ shown here is also equipped with the cable seal 3, so no prior overmolding is necessary.

[0045] The cable manager 2‴ has 22 test openings. Each test opening is assigned to an electrical conductor 5 of the cable 4. In Figure 11 A test device 30 is shown, which is equipped with contact pins 23 that can be inserted into the test openings 22. This electrically contacts the electrical conductors 5 in the cable manager 2. The contact pins 23 are connected at the other end to control conductors 24, which are coupled to test electronics (not shown). This allows verification of whether the electrical contact of the electrical conductors 5 at the junction box 10 has been correctly established.

[0046] In Figure 10Figure 30 describes a contacting process for the cable connection unit 1 to the junction box 10 according to the invention. The test device has two internal ribs 25 which fit precisely into the contact openings 6 of the cable manager 2, 2', 2", 2'. The test device 30 presses the connection unit 1 vertically – in the contact direction KR – into the connection area 11 of the junction box 10. The test device 30 generates the force necessary to press the electrical conductors 5 into the insulation displacement connectors 14. If contact is successful, the test device 30 activates a corresponding signal, for example, a green LED. The test device 30 is then removed, and the cover 15 of the junction box 10 can be closed.

[0047] The connection unit 1 can have cable managers 2, 2', 2", 2‴ on both sides, so that two adjacent connection boxes 10 can be electrically contacted with each other via one connection unit.

[0048] Even though the figures show various aspects or features of the invention in combination, it is apparent to the person skilled in the art – unless otherwise stated – that the combinations shown and discussed are not the only possible ones. In particular, corresponding units or sets of features from different embodiments can be interchanged. Reference symbol list

[0049] 1 Cable connection unit 2 Cable manager 3 Cable seal 4 Cable 5 Electrical conductor 6 Contact opening 7 Screw 8 Locking arm 9 Contact pin 10 Junction box 11 Connection area 12 Circuit board connector 14 Insulation displacement connector 15 Cover 16 Recess for cable 4 17 Circuit board 18 Recess 19 Conductor holder 20 Stud 21 Stud opening 22 Test opening 23 Contact pin of test device 30 24 Control conductor 25 Web 26 Web 28 Test device SR Insertion direction KR Contact direction

Claims

1. Cable connection unit (1) for a connection box (10), consisting of - a cable (4) which has at least two but preferably four electrical conductors (5) which are surrounded by a cable sheath, - a cable seal (3) radially enclosing the cable sheath, and - a cable manager (2, 2', 2'', 2‴) in which the at least two, preferably four, electrical conductors (5) are held fanned out, characterized in that the cable manager (2‴) has testing openings (22), wherein each testing opening (22) is associated with one electrical conductor (5).

2. Cable connection unit (1) according to Claim 1, characterized in that the cable seal (3) is a one-piece injection-moulded part and is fastened to the cable sheath by means of an injection-moulding process.

3. Cable connection unit according to either of the preceding claims, characterized in that the cable manager (2, 2') is a one-piece injection-moulded part and is fastened to the electrical conductors (5) by means of an injection-moulding process.

4. Cable connection unit (1) according to either of the preceding Claims 1 and 2, characterized in that the cable manager (2", 2‴) has a two-part design, wherein the two parts (2a, 2b) can be interlocked with each other via latching means.

5. Cable connection unit (1) according to one of the preceding claims, characterized in that the cable manager (2, 2', 2", 2‴) has two contact openings (6) which each have an essentially rectangular cross-section.

6. Cable connection unit (1) according to the preceding claim, characterized in that the contact openings (6) are arranged, in the plugging direction (SR), one behind the other and offset relative to one another.

7. Cable connection unit according to one of the preceding claims, characterized in that the cable (4) has in each case one cable manager (2, 2', 2'', 2‴) and one cable seal (3) on both sides.

8. Cable connection unit according to one of the preceding claims, characterized in that the cable (4) has a length of no more than three metres.

9. System consisting of a connection box (10) and a cable connection unit (1) according to one of the preceding claims, wherein the connection box (10) has at least one socket region (11) for the cable connection unit (1) in which the cable seal (3) and the cable manager (2, 2', 2'', 2‴) can each be inserted, characterized in that the socket region (11) of the connection box (10) has insulation displacement contacts (14), and in that the system has a test device (30) by means of which the correct electrical contacting between the respective insulation displacement contact (14) and the associated electrical conductor (5) can be checked.

10. System according to the preceding claim and Claim 5, characterized in that in each case at least two insulation displacement contacts (14) correlate with one contact opening (6) of the cable connection unit (1).

11. System according to one of the three preceding claims, characterized in that the connection box (10) has a hinged cover (15).

12. System according to the preceding claim, characterized in that the test device (30) has contact pins (23) which can each be pushed into a testing opening (22) of the cable manager (2‴).

13. Method for connecting a cable connection unit (1) according to one of the preceding Claims 1 to 8 to a connection box (10) from the system according to one of the preceding Claims 9-12, a) wherein the cable seal (3) and the cable manager (2, 2', 2'', 2‴) are inserted into a connection region (11) of the connection box (10), b) the cable manager (2''') is pushed down with the test device (30), c) as a result of which the electrical conductors of the cable (5) are each pushed into an insulation displacement contact (14) of the connection region (11) and consequently electrically contacted.

14. Method for connecting a cable connection unit (1) according to the preceding claim, characterized in that a first end of the cable (4) is connected to a first connection box (10) and a second end of the cable (4) is connected to a second connection box (10).