Branching part for an electrical network

Abstract: The invention relates to a branching part (3) for an electrical network comprising: a multi-pole input (5) for receiving a multi-pole plug-in connector (4), a multi-pole output (6) for receiving a second multi-pole plug-in connector (4), means for connecting the respective input (5) and output (6) poles to one another, and a second output (7) including at least a first conductive element (8). In order to simplify and expedite the electrical installation work the branching part further comprises: at least two optional contact parts (11 to 13) connected to the respective input poles (5), and a connecting part (15) through which the conductive element (8) of the second output (7) can be connected to one of said optional contact parts (11 to 13) for establishing contact between the conductive element (8) and the input pole (5) corresponding to the selected contact part.

Description: The invention relates to the construction of an electrical network and to the connection of components to the electrical network. In particular, the invention relates to a branching part for an electrical network, through which a fixed electrical network in a building can for instance be branched to the different components thereof. In such applications which are likely to need alterations in the electrical installations later on, it is desirable that the electrical network is implemented from the very start in such a manner that the alterations are easy to carry out afterwards. Such a need is typically found, for example, in exhibition stand structures and in transformable office and commercial buildings, in which the position of partition walls most likely has to be altered at some stage. If the couplings of electrical components, such as lighting fixtures, ventilators and sockets, are originally carried out in these targets in a conventional manner, i.e. by connecting the electrical components to the electrical network using fixed cable installations, it is very time-consuming and laborious to shift the electrical components afterwards. Also at the initial installation stage, or when an electrical network is constructed for the first time in a particular space, the installation work carried out as conventional fixed installation is time-consuming. Thus, instead of the above-described conventional fixed installations based on cables and screw joints, solutions are introduced, in which the electrical network components are provided from the very start with plug-in connectors. Consequently, the installation to be carried out on location becomes easier, as in practice such an installation is carried out by connecting the plug-in connectors of cables and electrical components to one another. Such an installation is significantly faster and more flexible than the conventional solutions. The introduction of plug-in connectors when installing electrical networks has allowed the components in an electrical network to be more rapidly connected together, but the installation of electrical networks still involves time-consuming and laborious steps. One such step is to select a phase for a component in the electrical network. In known solutions the electrical network components are chained to one another in such a manner that they include, for example, two plug-in connectors, whereof the first one is an input and the second one an output. Through the output, electricity is conducted from said electrical network component to the next electrical network component by means of a cable. In order for such an electrical component chain to load the network as evenly as possible, the components in the chain are typically connected to different phases. In known solutions this is carried out, for example in lighting fixtures, so that an electrician disassembles the lighting fixture in order to have access to the electrical wires inside the casing. After this the electrician connects the electrical wire of the lamp in the lighting fixture to the pole of the plug-in connector through which the lamp can be connected to the appropriate phase. Finally the electrician reassembles the lighting fixture. The choice of the above-mentioned phase for the lighting fixture is understandably fairly time-consuming and difficult, particularly when considering that the lighting fixtures are typically placed in the ceiling that is hard to reach. In addition the number of lighting fixtures may be relatively high, in which case the disassembly and reassembly of all the lighting fixtures take up a significantly long time. Previously there is known from WO9207396 a connector with a mechanism which makes an outlet of the connector switchable between different phases. However, such a solution which requires integrated moving parts is rather complex, in certain situations unreliable, and also relatively expensive. It is an object of the present invention to solve the above problem associated with the prior art solutions and to provide a branching part and an electrical network component expediting and alleviating the installation of an electrical network. These objects are achieved with a branching part for an electric network as defined in independent claim 1. The invention is based on the idea that the electrical installation work and more particularly the choice of the phase for an electrical component are significantly alleviated and expedited when a branching part is used in the electrical network, and the connecting part of the branching part allows to select the input pole that the branching part connects to the electrical network component. Thus, the choice of the phase for the electrical network component does not require the internal wires of the electrical network component to be reconnected, but it suffices to set the connecting part of the branching part to an appropriate position. In accordance with the invention the branching part or the electrical network component in which the branching part of the invention is utilized, is preferably formed in such a manner that the connecting part functioning as a phase selector is accessible from the outside of the electrical network component. Consequently the need to disassemble and assemble the electrical network component during installation work can be avoided. The most significant advantages that the solution of the invention provides are to considerably expedite and alleviate the installation of an electrical network as well as the alteration work of a completed electrical network, and thereby reduce the costs associated with the works. The preferred embodiments of the branching part of the invention are disclosed in the dependent claims 2 to 3. In the following the invention will be described by way of example in more detail with reference to the accompanying drawings, in which Figure 1 shows an electrical network part, Figures 2a to 2c show a first preferred embodiment of a branching part of the invention, Figure 3 shows a second preferred embodiment of the branching part of the invention, and Figure 4 shows a counterpart of the branching part of the invention. Figure 1 shows an electrical network part. Figure 1 illustrates several electrical network components 1 that may be lighting fixtures, for example. The lighting fixtures are chained to one another by means of cables 2 supplying the required electricity for the lighting fixtures. In the description below, the cables are assumed by way of example to comprise five conductors, and thereby to include three phases, the earth and zero. The electrical components 1 in Figure 1 are provided with branching parts 3, to which the cables 2 are connected through plug-in connectors 4. The branching parts thus comprise an outlet connector in addition to an inlet connector, to which the electrical cable 2 to be connected to the following electrical network component can be connected. The branching parts further comprise a second output (not shown in Figure 1), through which electricity can be connected to the electrical network component to which the branching part is attached. Figures 2a to 2c show a first preferred embodiment of the branching part of the invention from three directions. The branching parts 3 in Figures 2a to 2c correspond with the branching parts 3 which are used in connection with the electrical network components 1 shown in Figure 1. The branching part 3 in Figure 2 includes an input 5 that is shaped to receive a multi-pole plug-in connector. The branching part also includes an output 6, which is also shaped to receive a multi-pole plug-in connector. The respective input 5 and output 6 poles are connected to one another. In the situation shown in Figures 2a to 2c the branching part is intended to be used in three-phase electrical connections. Therefore both the input 5 and the output 6 include five poles, whereby one pole exists for each of the three phases (L1, L2, L3). The two remaining poles are the earth pole and the zero pole. The branching part in Figure 2 also includes a second output 7. Electricity is connected through the output 7 to the electrical network component, to which the branching part is attached (the lighting fixture in Figure 1). The output 7 comprises three conductors 8 to 10 in Figures 2a to 2c. The conductor 8 is connected to a selected input pole, or to a selected phase, as will be explained below. The conductors 9 and 10 are, in turn, permanently connected to the earth pole of the input 5 and to the zero pole of the output 6. Figure 2a shows that the branching part 3 comprises three contact parts 11 to 13, which are connected to the different phases of the output, i.e. to the different input 5 and output 6 poles. Each phase (L1, L2, L3) is therefore provided with a specific contact part. In Figures 2a to 2c the contact parts are formed of holes to which contact surfaces are arranged. The branching part further comprises a feeding hole 14 that also includes a contact part and that is connected to the conductor 8 of the second output 7. The contact parts 11 to 13 and the feeding hole 14 allow the conductor 8 of the second output to be connected to the selected phase (L1, L2 or L3), or in practice to the selected input pole 5 and correspondingly to the output pole 6. This is carried out by means of a connecting part 15 functioning as a phase selector. The connecting part is formed in the embodiment shown in Figures 2a to 2c mainly of a U-shaped conductive part, whose first end 16 is inserted into a selected contact part 11 to 13. A second end 17 of the connecting part is, in turn, inserted into the feeding hole 14. The connecting part 15 thus establishes contact between the selected input 5 and output 6 pole and the conductor 8. In practice this means that the conductor 8 as well as the electrical network component connected to the conductor 8 can be connected to the desired phase (L1, L2, L3). In Figure 2c the connecting part 15 is set into position so as to connect the conductor 8 to the phase that is connected to the contact part 11. The contact parts 11 to 13 are preferably arranged at the same distance from the feeding hole 14. An electrician may therefore use the same connecting part irrespective of the phase to which he/she wishes to connect the electrical network component, to which the branching part 3 is arranged. However, the distance between the contact parts 11 to 13 preferably differs from the distance between the contact parts and the feeding hole, in order to avoid the chance that the electrician connects by mistake the different phases to one another by means of the connecting part 15. In the embodiment shown in Figures 2a to 2c the branching part is attached to the electrical network component already during manufacture and at the same time the conductors 8 to 10 are also connected to the electrical network component, such as a lamp in the lighting fixture or a contact in the socket. In such a case the electrical installation work is very easy on the installation site. This holds true as the electrician has direct access to the input 5 and output 6 in order to connect the plug-in connector into position. After this the electrician only needs to set the connecting part between one of the contact parts 11 to 13 and the feeding hole 14, and the electrical network component is connected to the selected phase. To check the phase later on is very easy, as it can be seen directly from the outer surface of the branching part without having to disassemble the electrical network component for this reason (as in the prior art solutions). Figure 3 shows a second preferred embodiment of the branching part of the invention and Figure 4 shows a counterpart of the branching part 3' shown in Figure 3. The branching part 3' in Figure 3 corresponds to the branching part shown in Figures 2a to 2c except that in Figure 3 the second output of the branching part 3' is formed of a plug-in connector 7'. The branching part 3' is therefore used in Figure 4 together with a visible counterpart 18'. When manufacturing an electrical network component (such as a lighting fixture), a counterpart 18' is attached thereto. At the same time the electrical network component is connected by means of conductors to the counterpart 18' through connectors 20' to 22' therein. The connectors 20' to 22' may be, for example, spring connectors for receiving individual electrical conductors. The counterpart 18' comprises a plug-in connector 19' that forms the counterpart of the plug-in connector 7' of the second output in the branching part 3'. In this embodiment the branching part is therefore attached to the electrical network component by connecting the plug-in connectors 7' and 19' to one another. A connecting part 15 is used with the branching part shown in Figure 3 that corresponds to the one explained above in connection with Figures 2a to 2c. Thus the pole 8' of the second output in the branching part 3 as well as the electrical network component, to which the branching part is attached through the counterpart 18', can be connected to the desired pole at the input 5 and correspondingly at the output 6 of the branching part. This allows to select the phase for the electrical network component in a similar way as explained in Figures 2a to 2c above. It is understandable that the above description and the Figures associated therewith are merely intended to illustrate the present invention.

Claims: A branching part (3, 3') for an electrical network comprising: a multi-pole input (5) for receiving a multi-pole plug-in connector (4), a multi-pole output (6) for receiving a second multi-pole plug-in connector (4), means for connecting the respective input (5) and output (6) poles to one another, and a second output (7, 7') including at least a first conductive element (8, 8'), at least two optional contact parts (11 to 13) connected to the respective input poles (5), and a connecting part (15) through which the conductive element (8, 8') of the second output (7, 7') can be connected to one of said optional contact parts (11 to 13) for establishing contact between the conductive element (8, 8') and the input (5) pole corresponding to the selected contact part, characterized in that the connecting part (15) is a movable part including a first end (16) to be inserted into a feeding hole (14) through which contact is established between the connecting part (15) and the conductive element (8, 8') of the second output, and said contact parts (11 to 13) are arranged to the branching part (3, 3') so as to be placed at the same distance from the feeding hole (14), the distance being different from the one between the contact parts (11 to 13), whereby the connecting part (15) can be set into a position in which the second end (17) thereof comes in contact with the selected contact part (11 to 13). A branching part as claimed in claim 1, characterized in that said branching part (3, 3') is the branching part of a fixed electrical network in a building, and in that the input (5) comprises a pole at least for each phase, the branching part (3, 3') comprises phase-specific contact parts (11 to 13) connected to the respective poles at the input (5), and a movable connecting part (15) forms a phase selector that allows the conductive element (8, 8') to be connected to the selected phase. A branching part as claimed in claim 1 or 2, characterized in that said conductive element is composed of an electrical conductor (8) or of a pole (8') in a plug-in connector (7') forming the second output of the branching part.

Inventors: MATIKAINEN ESKO, VIRTANEN JARMO, MATIKAINEN, ESKO, VIRTANEN, JARMO
Applicants: ENSTO ELECTRIC AB OY, OY ENSTO ELECTRIC AB
Application year: 2001
Main classification: H01R25
IPC codes: H01R31, H01R25