NEW ZEALAND PATENTS ACT, 1953
No: 548631 Date: 19 July 2006
COMPLETE SPECIFICATION
AN ELECTRICAL SOCKET I ^ectuai Property
Office of N.Z.
1 9 JUL 2007
B E c e|vf [-•
We, SCHNEIDER ELECTRIC NEW ZEALAND HOLDINGS LIMITED, a company duly incorporated tinder the laws of New Zealand of, 11 Moncur Place, Christchurch, New Zealand, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
FIELD OF INVENTION
The invention relates to an electrical socket suitable for connection to an electrical cord or flex.
BACKGROUND
The electrical socket of the invention has been developed primarily for use as a pendant socket. A pendant socket is a socket mounted to one end of an electrical cord or flex (herein referred to generally as a flex for convenience) which is suspended from overhead, so that in a commercial or factory or similar environment it is possible to reach up and insert a plug attached for example to an appliance or machine or an extension cord, into the pendant socket. The upper end of the hanging flex mounting the pendant socket is typically connected to an electrical fitting mounted to the ceiling or similar. Typically the upper end of the flex is also physically supported from the ceiling against downward mechanical loads on the pendant socket.
The socket of the invention may also be used in non-pendant applications, where it is desired to provide a switched socket.
SUMMARY OF INVENTION
The invention provides an improved or at least alternative form of switched electrical socket, particularly suitable for use in pendant socket applications.
In broad terms the invention comprises an electrical socket comprising a socket body for internally mounting a switch module within the socket body and having an entry to the socket body for insertion of a switch module during assembly of the electrical socket, a switch module for mounting within the socket body, a manually operable switching element mounted to the socket body so as to be operable from the exterior of the socket body to switch the socket and engageable within the socket body by the switch module when the switch module is inserted into the socket body, and a formation within the socket body and/or on the switch module adapted to slidingly engage the switch module or socket body or to interengage, on insertion of the switch module into the socket body, and shaped to move the switch module towards the switching element on insertion of the module into the socket body to cause the switch module to couple with the switching element when the switch module is fully home within the socket body.
Preferably the socket body comprises two or more longitudinally extending formations or rails within the interior of the socket body opposite the switching element, on which the switch module slides on insertion into the socket body, and which are shaped to move or raise the switch module towards the switching element within the socket body as the switch module is inserted fully home within the socket body.
The term 'comprising' as used in this specification and claims means 'consisting at least in part of, that is to say when interrupting independent claims including that term, the features prefaced by that term in each claim will need to be present but other features can also be present.
BRIEF DESCRIPTION OF THE FIGURES
The invention is farther described with reference to the accompanying drawings which show a preferred form of an electrical socket of the invention, by way of example and without intending to be limiting. In the drawings:
Figure 1 is an exploded view of the components of the preferred form electrical socket,
Figure 2 is a view from one end of the preferred form electrical socket, with the cover thereof closed,
Figure 3 is a transverse cross-section view through the socket of Figures 1 and 2, along a line I-I of Figure 4,
Figure 4 is a longitudinal cross-section view of the socket along a line II-II of Figure 2,
Figure 5 is a longitudinal cross-section view of the socket along a line III-III of Figure 2, and Figures 6a and to 6d are schematic cross-section views illustrating insertion of the switch module into the socket body of the preferred form electrical socket and engagement of the switch module with the switching element on the socket body.
DETAILED DESCRIPTION OF PREFERRED FORM
Referring to Figures 1 to 5 the preferred form electrical socket comprises socket body 1 having a hollow interior and a switch module 2 which during assembly of the socket is inserted into the interior of the socket body 1. When the module 2 is inserted fially home only the front face plate 3 of the module 2 is exposed at the front of the socket, so that a plug may be inserted into the socket to electrically connect an appliance or machine or extension cord or similar to the socket. In the particular form shown the socket is for receiving a three pin plug with phase neutral and earth pins in the configuration shown, but the socket may be formed for receiving a plug with pins in any other configuration.
When inserted fully home the module 2 is secured in the socket body by screws 17 (see Figure 5) which thread through apertures in the face plate 3 and into the socket body on either side at 18.
In the preferred form the socket has a spring loaded cap or cover 4 which is pivotally mounted to one side of the front of the socket by a pin 5 which passes through a hole extending transversely through part 6 of the cap 4 and through lugs 7 between which part 6 is entered
during assembly of the socket. A sealing ring 21 is provided on the socket body. Providing such a cap protects against entry of water or dirt or debris into the socket when not in use, but is optional.
A switching element generally indicated at 12 is mounted to the socket body. The term "switching element" is used genetically and in the preferred form comprises a slide component 13 with tab 13a on the under side thereof which engages into a pin 14. The slide 13 is mounted for sliding movement in the direction of arrow A in Figures 1 and 4 to switch power supply from the socket on and off, in a separate part la of the socket body 1. When the socket body and switching element 12 are assembled, the lower end of the pin 14 extends through part 15 and through an aperture 17 in the socket body 1, and is exposed within the interior of the socket body (see Figure 4 for example).
The socket is connected to the end of a length of electric flex by the flex passing through cable nut 8 and seal 9 into the rear end or tail 10 of the socket body 1, and in the preferred form through the cord clamp 11 formed as part of a back end part of the module 2. The wires of the flex (typically phase, neutral and earth wires) are connected to terminations in the socket module 2.
The module 2 also contains a mechanical switch (not shown) within the module,
typically for switching between the phase termination point and fixed phase contact of the socket. The switch within the module 2 is mechanically operated through intermediate rocker element 16 which is exposed at the exterior of the body of the module 2 as shown.
Between the interior of the socket body 1 and the module 2 are provided one or more formations for sliding engagement on insertion of the switch module 2 into the socket body 1. In the preferred form two longitudinally extending formations 15 or rails are provided within the interior of the socket body as shown. The rails 15 ramp upwardly from the entry and into the interior of the socket body. In assembly of the electrical socket, after the end of flex to which the socket is to be connected has been inserted through the seal 9, socket body 1, and cord clamp 8, and has been terminated to the module 2, then the module is inserted back and pushed into the interior of the socket body 1. As the module enters the socket body it slides on and is guided by the rails 15 as schematically shown in Figures 6a and 6b. As the socket is inserted fully home into the socket body, the inter-engagement between the rails 15 and the socket body 2 moves the socket body towards the switching element 12. In particular in the preferred form the part 16 of the module 2 is brought together to engage the pin 14, as shown in Figure 6c, until when the module is fully home within the socket body as shown in Figure 6d, the pin 14 and part 16 of the module 2 are fully inter-engaged or coupled so that, after assembly, when the switch slide 13 of
the assembled socket is moved the switch within the module will be switched to connect or disconnect power.
In the preferred form lugs 19 are provided on either side of the socket body 2 as contact or engagement points with the rails 15. In addition the rails 15 comprise steeper ramp part 15a on either side thereof to raise the switch module towards the switching element 12 in the last part of the sliding movement of the module into the socket body. The rails 15 also include a recess 15b at the end of the rails 15 on either side, into which the lugs of the module seat or may snap-fit when the module is fully home within the socket body 1.
An advantage of the design of the preferred form electrical socket is that it is relatively waterproof. For example the socket body is not broken longitudinally by being formed as two body halves to enable a switch module to be fitted in the socket body during assembly of the socket. The switch element 12 is relatively integral with the socket body 1. Typically the components of the switching element 12 namely the slide 13, pin 14, and part 15 will be mounted to the part la of the socket body and in turn to the major part 1 of the socket body at the factory, so that where the socket is connected to an electrical flex on site by an electrician for example, an electrician need only after inserting the flex through the socket body as described and terminating the flex on the module 2, then slide the module into the interior of the socket body and secure it by insertion of the screws 17, and then tighten the cord clamp 8 around the flex at the rear end of the socket. This is enhanced by providing the cap 6 which normally covers the front of the socket when not in use.
In the preferred form there are two rails 15 or longitudinally extending formations on either side of the interior of the socket body. In an alternative form in addition a central longitudinally extending formation rail may be provided between two rails on either side similar to the rails 15, or alternatively again a single central rail may extend into the socket body which is engaged by the module as the module is inserted into the socket body, and is shaped to raise the module towards the switching element 12 in the side wall of the socket body 1. In the preferred form shown the rails 15 are provided opposite the switching element 12 but in an alternative form the module may be guided as it is inserted into the socket body by extending formations provided on either side of the socket body, which are angled so as to bring the module into position relative to the switching element 12 as the module is inserted home. Alternatively again instead of providing lugs 19 or equivalent rails 15 or other longitudinally extending formations within the socket body the module may engage slots provided along the interior of the module. Further alternatively, in any of the arrangements described the formations on the socket body may instead of rails or similar comprise slots into which protruding elements from the module
engage, to guide the module as it slides into the socket body and which bring the module into inter-engagement with the switching element 12.
In the preferred form shown the socket body comprises the part la formed separately from the major part of the socket body 1 but alternatively the socket body may be formed as a single integral component, having an aperture over which a slide or switch rocker is mounted and through which a tab or equivalent of the slide or rocker extends into the interior of the socket body to be engaged by the module.
In other forms the slide 13 shown in the drawings may be replaced by a rocker switch. Alternatively again the socket may be switched by a one or more push buttons which engage cooperating mechanical on and off operative parts of the module 2 through a side wall of the socket body. The switching element which is mounted to the socket body or in particular in a side wall of the socket body so as to be operable from the exterior of the socket body while engaging with the module within the socket body, may be a simple single part mechanism, or a multi part mechanism as shown in the accompanying drawings for example and as referred to previously the term "switching element" is used genetically and is to be understood as extending to various forms of switch mechanism as may be used.
In the preferred form the cable nut 8 is provided which threads into the rear end 10 of the socket body with the seal 9 but this is preferred and not essential and a cord clamp may be provided in any other suitable form or omitted.
The preferred form electrical socket described above is designed as a pendant socket and comprises a lug 20 on the socket body 1 from which the socket may be suspended in a pendant application. An electrical socket of the invention may be used in other non-pendant applications such as a socket for connection to an extension cord (where it is desired to provide a switched socket to an extension cord) for example.
The foregoing describes the invention including a preferred form thereof. Alterations and modifications as would be obvious to those skilled in the art are intended to be incorporated within the scope hereof, as defined in the accompanying claims.