A socket-switch unit

Abstract: The unit comprises a container formed by a first portion (10) and a second portion (12) separable from one another, a socket (14) mounted in the second portion (12) of the container and accessible from outside the container for the insertion of a plug therein, and a switch (13) mounted in the second portion (12) of the container and operable from the exterior. To permit the production of units in two different versions, one with a socket accessible from the front wall and one with a socket accessible from below, with a minimum of modifications, the unit comprises a connector electrically connected between the switch (13) and the end wires of a supply line (15) and formed by a first connection element (20a) and a second connection element (20b) which are separable and of which the first (20a) is mounted in the first portion (10) of the container and has connectors (25) for electrical connection to the end wires of the line (15) and the second (20b) is mounted in the second portion (12) of the container and electrically connected to the input connectors of the switch (13).

Description: The present invention relates to a socket-switch unit for electrically connecting a load, connected to the socket, to an electrical-energy supply line, in a controllable manner, more particularly to a socket-switch unit as defined in the preamble of claim 1 and known from DE 7 917 153 U. A socket-switch unit comprising a box-like container formed by two portions separable from one another and containing a socket, a switch and possibly protection devices is known. One of the two portions of the container, which is usually fixed to a vertical wall, has an opening for the passage of a cable comprising end wires of a supply line. The switch is mounted in one of the portions of the container and is operable from the exterior through a suitable opening of the container. The input connectors of the switch are connected to the line ends, possibly via protection devices such as fuses or automatic circuit breakers, and the output connectors are connected to the socket. Units of this type often have mechanical interlocking devices between the switch and the socket to prevent a plug from being inserted in the socket or removed from the socket when the switch is closed, and are used in difficult environmental conditions in which it is nevertheless important to ensure maximum safety of operation, for example, on building sites and in workshops. Known socket-switch units are commonly produced in two versions, that is: a first version in which the socket is mounted in the portion of the container which is normally fixed to a vertical wall and is arranged in a manner such that the plug can be inserted from below through a lower side of the container, and a second version in which the socket is mounted in the other portion of the container, more precisely, on the side opposite to that which is fixed to the wall, so that the plug can be inserted from the front. In both versions, the switch and the socket are both mounted in the same portion of the container. For greater clarity, the two versions are shown schematically in Figures 1 and 2, in which the two portions of the container are indicated 10 and 12, the switch and the socket are indicated 13 and 14, respectively, the supply cable extending through an opening 16 of the container is indicated 15, and a plug to be inserted in the socket is indicated 17. The need to provide two distinct structures for the two versions is clear and this constitutes a disadvantage for production. As can easily be noted, although the two versions perform exactly the same function, they are differentiated in that, in one, the two electrical devices, that is, the socket and the switch, are in the portion of the container in which the opening is provided for the passage of the supply wires whereas, in the other, the two devices are in the portion of the container which does not have an opening. The two versions thus have different wiring; the first permits an easy electrical connection of the supply wires to the input connectors of the switch, whereas the second requires a considerable length of the supply wires for fixing to the connectors of the switch and, if the two portions of the container are not articulated to one another, also involves some difficulty in the wiring operations. To prevent these disadvantages, according to the invention, the two electrical devices are mounted in the portion which does not contain the opening for the supply wires and a connector is provided, connected electrically between the switch and the end wires of the line. This connector is formed by a first element mounted in the portion which contains the opening, which has connectors for electrical connection to the supply wires, and by a second element mounted in the other portion of the container and connected to the input connectors of the switch. The invention will be understood further from the following detailed description of a non-limiting embodiment thereof, given with reference to the appended drawings, in which: Figures 1 and 2 show schematically two socket-switch units according to the prior art, Figure 3 shows, in perspective, two portions of a socket-switch unit according to the invention, ready to be fitted together, and Figures 4 and 5 are two views, that is, a front view and a lateral section, respectively, of the unit of Figure 3 with the two portions joined together. The socket-switch unit according to the embodiment shown in Figures 3 to 5, in which elements identical or similar to those of Figures 1 and 2 are indicated by the same reference numerals, comprises a box-like container in which a socket 14, a switch 13, a connector 20a, 20b and three automatic circuit breakers 21 are mounted. The container is formed by a first shell 10 and by a second shell 12 which can be fixed together by suitable, conventional, releasable fixing means, for example, screws (not shown), so as to form a compartment for the electrical devices and the various electrical interconnection means. The first shell 10, which is fixed to a vertical wall by conventional means, not shown, has an opening 16 for the passage of a cable 15 containing the end wires of an electrical-energy supply line, for example, the three wires of a three-phase alternating supply line. Instead of being an independent element, as shown, the first shell 10 could form part of a more complex structure, for example, of an electrical switchboard comprising other electrical devices. The three automatic circuit breakers 21 are mounted in the first shell 10 by means of a track 22. They have three input connectors 23 in the form of clamps to which the three end wires of the line 15 are fixed, three output connectors 24, also in the form of clamps, and a common operating lever 28. A first connection element 20a, also mounted in the first shell 10 by fixing means, not shown, has three clamps 25 and three clip contact elements 26, each electrically connected to a respective clamp 25. Three electrical wires 27 are fixed between the clamps 24 of the automatic circuit breakers 21 and the clamps 25 of the connection element 20a and, when the automatic circuit breakers 21 are closed, electrically connect the three ends of the supply cable 15 to the three clip contact elements 26. The switch 13 is mounted in the second shell 12 by conventional fixing means, not shown. It has three input connectors in the form of blade contact elements 30, three output connectors in the form of clamps 31, and an operating member represented by a lever 32 which is fixed to a pin 33 extending through the switch 13 and projects from the front wall of the shell through a slot 38. The blade contacts 30 together constitute a second 'connection element 20b complementary with the first connection element 20a and formed integrally with the switch. However, if necessary, a second connection element separate from the switch but electrically connected to its input connectors by suitable conductors may be produced. The socket 14 is also mounted in the second shell 12 by suitable fixing means and is accessible from the lower side for the insertion of a plug. Each of three wires 34 is fixed, at one end, to a respective contact of the socket 14 and, at the other end, to a respective clamp 31 of the switch 13. The second shell 12 has, in its front wall, a window 35 which, when the two portions of the container are fitted together, is disposed in the region of the operating member 28 of the automatic circuit breakers 21. The window 35 is accessible by the opening of a door 36 which is joined to the remainder of the shell 12 by means of a pin 37. Suitable mechanical interlocking means, of known type and therefore not shown, interconnect the operating member 32 of the switch 13, the socket 14, and the door 36 in a manner such that the insertion of a plug in the socket 14 or its removal therefrom is prevented if the switch 13 is in the closure position, and in a manner such that the door 36 can be opened only with the switch 13 open. The presence of these interlocking means is indicated symbolically in Figures 4 and 5 by chain lines which join the three elements affected by this function. To form a socket-switch unit with a socket accessible from the front wall, it suffices to change the position of the socket 14. This involves purely a simple modification of the second shell 12 (in addition to a modification of the interlocking means, if such means are provided). No modification of the first shell 10 is required. By virtue of the invention, the two versions of the socket-switch unit mentioned at the beginning can be produced, in practice, from a single basic structure, with considerable advantages for the producer and distributor of the product. It will also be noted that the wiring problems of the prior art do not in fact arise because the electrical connections can be provided separately in each shell; the electrical connection between the two shells takes place automatically when the connection elements of the connector are coupled with one another when the two shells are fixed together.

Claims: A socket-switch unit comprising: a box-like container, formed by a first portion (10) and a second portion (12) separable from one another and having an opening (16) in the first portion (10) for the passage of end wires of an electrical-energy supply line (15), a socket (14) mounted in the second portion (12) of the container and accessible from outside the container for the insertion therein of a plug electrically connected to a load to be supplied, and a switch (13) mounted in the second portion (12) of the container, operable from outside the container, and having input connectors for electrical connection to the end wires of the line (15) and output connectors (31) electrically connected to the socket (14), characterized in that it comprises a connector electrically connected between the input connectors of the switch (13) and the end wires of the line (15) and formed by a first connection element (20a) and a second connection element (20b) which are separable and of which the first (20a) is mounted in the first portion (10) of the container and has connectors (25) for electrical connection to the end wires of the line (15) and the second (20b) is mounted in the second portion (12) of the container and electrically connected to the input connectors of the switch (13). A socket-switch unit according to Claim 1, in which the second connection element (20b) of the connector is integral with the switch (13). A socket-switch unit according to Claim 1 or Claim 2, comprising protection devices (21) electrically interposed between the connector and the end wires of the line (15) and having input connectors (23) for electrical connection to the end wires of the line (15) and output connectors (24) connected to the connectors (25) of the first connection element (20a). A socket-switch unit according to any one of Claims 1 to 3, comprising mechanical interlocking means between the socket (14) and the switch (13), preventing the insertion of a plug in the socket or the removal of a plug from the socket if the switch (13) is in the closure position. A socket-switch unit according to Claim 4, in which the second portion (12) of the container has a window (35) in the region of the protection devices (21), and in which an openable door (36) is provided on the window (35) and comprises further mechanical interlocking means between the switch (13) and the door (36), allowing the door to be opened only with the switch open.

Inventors: GIUDICI LUIGI, GIUDICI, LUIGI
Applicants: BTICINO SPA, BTICINO S.P.A.
Application year: 1999
Main classification: H01R13
IPC codes: H01R9