WO2008114061A1

WO2008114061A1 - Electrical connector

Info

Publication number: WO2008114061A1
Application number: PCT/GB2008/050205
Authority: WO
Inventors: Clive Meech
Original assignee: Clive Meech
Priority date: 2007-03-22
Filing date: 2008-03-20
Publication date: 2008-09-25
Also published as: GB2460988B; GB2460988A; GB0705480D0; GB0918340D0

Abstract

An electrical connector (10) adapted to be mounted below a surface (12A) of a substrate (12). The connector comprises a first part 18 having a power output (26,27), which first part is movable between an extended position and a retracted position. In its extended position at least part of the first part (18) extends beyond the surface of the substrate (12) so that it can supply electrical current to an electrical device to be connected thereto, whereas in its retracted position the first part (18) is stowed below the surface (12A) of the substrate. The electrical connector may also comprise a switch adapted to enable electrical current to pass to the power output (26,27), only when said first part (18) is in its extended position.

Description

ELECTRICAL CONNECTOR

The present invention relates to an electrical connector for connecting electrical appliances to an electricity supply. In particular, the invention relates to an electrical connector which is to be installed in a surface, connected to an electricity supply and capable of being stowed below/behind the surface when not required.

A wide variety of electrical appliances are available for use especially in domestic and commercial kitchens, and these require a mains supply of AC electricity to operate. Most of these appliances are provided with a flexible lead having a conventional plug on one end which is connected to a conventional wall mounted three or two pin electrical plug socket. Such sockets are commonly furnished on the walls of most kitchens and are wired into a ring main circuit provided in the building. The other ends of such leads are often hard wired to the appliance or connect to a differently configured socket on the appliance.

Trailing electrical leads are often a nuisance for various reasons. Sometimes they are too long and are left sprawling across a work surface taking up valuable space and looking unsightly. Moreover, long electrical leads left trailing across the floor or hanging from kitchen surfaces can compromise the health and safety of people working in kitchens. In domestic kitchens there is also the health and safety of young children and pets to consider since they might attempt to grab or bite a lead if it is left trailing across the floor or indeed hanging over the edge of a kitchen work surface. Such long leads may be connected to kettles or deep fat fryers which, if pulled could lead to the child or family pet being severely burnt. On the other hand, leads can sometimes be too short to reach the nearest wall mounted plug socket and so an extension lead is required, which suffers from the same drawbacks and is also highly inconvenient.

Many appliances are used only infrequently and so they are often stored and leads can be unwieldy and cumbersome. Furthermore, quite often an insufficient number of plugs sockets are provided at the location in which the appliance is to be used so a multiple socket adapter is required. Again, these are cumbersome and unsightly since often they are bulky and many leads may meet at a single point. Furthermore, some of these multi-plug adaptors have been condemned by health and safety authorities as being unsafe because they can overload and are prone to cause fires.

It is a principle aim of the present invention to overcome the above problems by providing a connector having electricity supplied thereto and which is adapted to connect directly to an electrical appliance, thus obviating the use of leads. It is a further aim of the present invention to provide a connector which is aesthetically pleasing and which is easily stowed out of sight when not in use. It is yet a further object of the present invention to provide a connector which is very safe and unlikely to pose fire hazards. According to the present invention, there is provided an electrical connector adapted to be mounted below a surface of a substrate, which connector comprises a first part having a power output, which first part is movable between an extended position whereat at least part thereof extends beyond the surface of the substrate so that it can supply electrical current to an electrical device to be connected thereto and a retracted position whereat said first part is stowed below the surface of the substrate.

The present invention is intended to be mounted in a substrate below a surface thereof, but the term "below" does not mean the surface must be horizontal and the appliance above it. Indeed the surface may be at any angle as long as the first part may be concealed when not in use, below or behind the outer surface of that substrate. This could equally apply to a situation where the first part moves generally up, across or down when going from the retracted position to the extended position.

In a preferred arrangement there may be provided a switch adapted to enable electrical current to pass to the power output only when said first part is in its extended position. Preferably, the switch and the first part are provided in a housing adapted to be mounted in a hole formed in the substrate. More preferably the housing is generally cylindrical so that it may be snugly mounted in a circular hole in the substrate. The hole may easily be prepared by use of a hole saw or other suitable means, or may be preformed in the substrate.

Preferably, the housing is generally tubular and the interior defines an internal space extending generally parallel to the direction of movement of the first part, which is slidably received therein. The axis of the housing is generally co-axial with the axis of the hole in the substrate. Preferably, the first part is a close sliding fit in the internal space of the housing, which internal space is preferably circular in cross section. This allows the first part to slide axially in the housing and if required rotate relative thereto. The first part may be sized to form a close running fit with the hole or housing which would serve to support the first part as it slides, but also inhibit the collection of debris in the space between said first part and the hole or the housing. Preferably, a seal is provided around the periphery of the first part which is arranged sealingly to engage the hole or housing so as to prevent the ingress of debris or liquid between the first part and the hole or housing where present.

Preferably, the outer end of the housing (ie the part that is at or adjacent the surface of the substrate) has an outwardly extending flange arranged to overlie the surface of the substrate and to assist in supporting the housing. A ring shaped seal could be provided beneath the flange so as to seal between the housing and the substrate. The surface of the substrate around the periphery of the hole may be recessed to receive the flange so that the upper surface of the flange is coplanar with the surface of the substrate.

In a preferred arrangement, the first part is resiliently biased towards its extended position. This may use biasing means in the form for example of a first spring. A catch mechanism may be provided to hold said first part in its retracted position against that bias. The biasing means may be a helical coil spring supported in the hole or the housing and which bears against the first part so as to urge said first part toward the extended position. The catch mechanism could include a number of different mechanisms to hold the first part in the retracted position. For example, the catch mechanism may require the first part to be rotated about its vertical axis to lock it in its retracted position, with counter rotation to release it. Most preferably, the catch mechanism comprises an arrangement by which the first part is locked in its retracted position automatically when pushed against the bias to that position, and release is achieved by a further push in the same direction against the bias until release occurs. Such mechanisms are widely known (sometimes they are called a "push to open push to close" mechanism or a "push catch") and so no further explanation is required here. -A-

In a preferred embodiment, a removable cap is provided and this is arranged to sit on the first part so as to overlie the power output. The shape and size of the cap corresponds to the shape and size of the hole or internal space in the housing so as to form a close running fit and enable the cap and first part to slide while minimising the space in which debris and moisture may collect. Preferably the cap has an upper surface that will be generally flush with the surface of the substrate when the first part is in the retracted position.

The switch may be provided on the first part and arranged to engage an abutment surface provided in the hole or the housing depending on the position of the first part, this engagement controlling the switch. In an alternative arrangement, the switch is provided in the hole or housing and movement of the first part alters the state of the switch. There exists a range of widely available switch mechanisms which would be suitable for controlling the flow of current to the power output. The switch may comprise a first electrically conductive contact (or pair of contacts) provided on the first part and a second electrically conductive contact (or pair of contacts) provided in the hole or housing, the first contact being arranged to engage the second contact when said first part is in its extended position. In a different arrangement, the switch may comprise a spring loaded pin mounted in the hole or housing and adapted to slide along an axis parallel to the axis of the hole. A first electrically conductive contact connected to the power input may be provided on the pin for sliding movement therewith and a second electrically conductive contact connected to the power output may be provided in the hole or the housing. In this arrangement, the pin is urged upwards by the spring so that the first contact engages the second contact and current runs through the power output. An abutment surface may be provided on the first part and which may be adapted to engage the pin and cause it to move downwardly when said first part is moved from its extended position towards its retracted position.

In a preferred embodiment, the housing extends downwardly beyond the substrate and has a threaded outer surface for receiving a collar. The collar may be tightened onto the external thread of the housing so as to secure the housing to the substrate. A power input connector may be provided to enable the present invention to be conveniently connected to a ring main or alternative power supply. Preferably, the input connector is easily accessible from beneath or behind the substrate and comprises a socket suitable for receiving a plug connected to the ring main or wire clamps for connection to power cable wires.

The present invention will find particular use in the kitchens although it can be used in many other types of location. Preferably the substrate in or through which the connector is located is a work surface, and more preferably a kitchen work top. The present invention also includes electrical appliances that are provided with an input connector adapted to connect to a connector as previously described. Such appliances may comprise for example a kettle, a deep fat fryer, a food processor a liquidiser or the like and would preferably have the input connector provided on a lower, rear or side surface thereof. In order that it may be better understood, but by way of example only, two embodiments of the present invention and certain modifications thereof will now be described in detail, reference being made to the accompanying drawings, in which

Figure 1 is a cross-sectional view of a first embodiment of the electrical connector in an extended position;

Figure 2 corresponds to Figure 1 but shows the electrical connector in its retracted position;

Figure 3 is a cross-sectional view of a second embodiment of the electrical connector in its extended position; and Figure 4 corresponds to Figure 3 but shows the electrical connector in its retracted position.

Referring to Figures 1 and 2, there is shown a first embodiment of the electrical connector generally indicated 10 that is adapted to be installed in a round hole 1 1 formed through a substrate 12. The connector 10 includes a generally tubular housing 13 comprising a circumferential sidewall 14 connected to a circular base 15. The upper end of the circumferential sidewall is provided with a circumferential flange 16 extending radially outwardly therefrom. The circumferential sidewall 14 of the housing 13 defines a generally cylindrical inner space 17 in which a first part 18 is mounted and arranged to slide axially therealong.

The first part 18 comprises a cylindrical socket 25, and a first circumferential skirt 19 depending downwardly from the circular base 20 of the socket 25. The circumferential skirt 19 is provided with upper and lower annular flanges 21 , 22 spaced axially apart so as to define an annular channel in which a sealing ring 23 is located. The diameter of the sealing ring 23 is approximately equal to the diameter of the inner space 17 and is arranged so that its circumferential surface sealingly engages the circumferential sidewall 14 of the housing 13 as the first part moves.

The socket 25 is arranged to be connected to a mating connector on an electrical appliance (not shown) when the first part is in the extended position. The socket may take a variety of forms but in this embodiment it comprises a circular channel 26 and a bore 27 arranged such that the axis of the bore 27 is coaxial with the axis of the circular channel 26 and the axis of the socket 25. In Figures 1 and 2 the socket 25 is integral to the first part 18 and together form a single moulded unit. However, in an alternative embodiment (not shown) the first part 18 and the socket 25 may be two or more separate parts that are fastened together during assembly. The first part 18 is slidable between an extended position (Figure 1 ) whereat the socket 25 extends above the upper surface 12A of the substrate 12, and a retracted position (Figure 2) whereat the socket 25 is positioned below the upper surface 12A of the substrate 12.

The first part also comprises a barrel 30 that extends downwardly from the circular base of the socket 25 and which is slidably received in a spring chamber 31 defined in a spring housing 32 located in the housing. The spring housing 32 is generally tubular and comprises a circular wall 33 upstanding from the edge of a circular base 34, the free end of the wall 33 remote from the base 34 has an outwardly extending flange 35 which threadingly engages a corresponding support flange 36 located midway along the housing. A pair of diametrically opposed protuberances 38 extends inwardly at the upper end of the spring housing 32 and these locate in a pair of diametrically opposed grooves 39 extending axially along the surface of the barrel 30. The grooves 39 extend from the upper end of the barrel 30 to a location near to but remote from the lower end, so as to define abutment faces 40 against which the protuberance will bear when at the extended position. A helical coil spring 41 is located in the spring chamber 31 and has a lower end seated on the circular base 34 and an upper end bearing against the bottom of the barrel 30 so as to resiliently urge the barrel and the first part 18 upwards toward the extended position until the abutment faces 40 abut against the protuberances 38. At least part of the first part 18 is constrained within the housing 13 due to the protuberances 38 bearing against the abutment faces 40. A rod 42 extends from the centre of the barrel 30 and when the first part 18 is moved to its retracted position the rod passes through an opening 43 formed in the circular base 34.

The first embodiment of the present invention also includes a push catch mechanism by which the socket 25 and first part 18 may be selectively retained in a retracted position (as shown in Figure 2), despite the spring 41 urging it upwardly towards its extended position. The push mechanism (not shown in Figures 1 and 2) is in this embodiment provided on the barrel 30 and, when the first part 18 is pushed down from the extended position, engages to retain the first part 18 at the retracted position until such time as an operator presses it down further which then causes the catch to disengage and allow the first part to slide upwardly under the force of the spring 41 . Such a mechanism is well known and so no further explanation is required here.

The electrical connector 10 also includes a switch mechanism for controlling the flow of electricity to the socket 25 such that the socket is only energised when in the extended position. The switch mechanism comprises a pair of electrically conductive limbs 51 mounted on a pin 52 upstanding from the centre of the base 15 and arranged to slide therealong. The limbs 51 extend laterally from the pin 52 in opposite directions and are resiliently biased upwardly by a switch spring 53 provided on the pin 52 below the limbs 51. The limbs 51 are electrically insulated from one another and electrically connected by wires (not shown) to a power input socket 54 mounted on the base 15 and arranged to connect to an external power supply (not shown) such as a ring main. The input socket 54 has three contact pins 57 that connect to live, neutral and earth wires.

A pair of electrically conductive contacts 55 are fixed to the base 15 and electrically connected to the output socket 25 by wires 56. The contacts 55 are arranged to engage the electrically conductive limbs 51 when the first part 18 is in its extended position. As the first part is moved to its retracted position, the rod 42 engages the uppermost limb 51 causing both limbs to move downwardly and disengage their respective fixed contact 55, thereby de-energising the socket 25. A removable protective cap 60 is provided and this prevents debris collecting in the socket 25 when the first part 18 is in its retracted position. Obviously when connected to an appliance the socket will be protected by that appliance. The cap is generally cylindrical and arranged to rest on socket 25 so as to overlie and conceal the electrical contacts. The cap comprises a top 61 and a wall 62 depending therefrom and which is sized to form a close running fit within the inner space 17 so as to permit the cap 60 to locate therein along with the first part 18. The upper surface of the top is generally coplanar with the flange 16 of the housing 13 when the first part 18 is in its retracted position.

The housing 13 is longer than the thickness of the substrate 12 such that a bottom portion of the housing extends below the substrate and is provided with a thread 64 formed thereon for threadingly receiving a collar 65. The collar 65 bears against an annular seal 66 which in turn bears on the underside of the substrate so as to secure sealingly the housing in said substrate.

To install the electrical connector 10 in a substrate such as a kitchen worktop, the hole 1 1 must first be formed in the work top at an appropriate place by using a suitable cutting tool such a hole saw or drill. The connector can then be inserted into the hole 11 and the collar 65 threaded onto the lower portion of the housing and tightened onto the underside of the kitchen top. The electrical supply (not shown) can then be connected to the input socket 54. To use the electrical connector 10, the cap 60 is pushed downwardly to release the first part 18 which moves to its extended position under bias of the spring 41. Once at its extended position the cap 60 can be removed and an appliance having a matching plug can be positioned adjacent or over the socket 25 and attached thereto. When the appliance is no longer needed it can be disconnected from the socket 25 and the cap 60 refitted. The cap 60 should then be pushed downwardly and fully home so that the release mechanism retains the first part in its retracted position against the bias of the spring. For permanently or temporarily positioned appliances the present invention allows the connection to be made without trailing wires, as the connection plug on the appliance can be concealed on the underside of the appliance.

In an alternative second embodiment shown in Figures 3 and 4 a different mechanism is used to hold the first part in the retracted position, but otherwise the design is the same and like part have been give like reference numerals. A pair of circumferential grooves 45 is provided in the surface of the barrel 30, which circumferential grooves 45 intersect the axially extending grooves 39. The circumferential grooves 45 are located towards the upper end of the barrel 30 such that they are generally coplanar with the protuberances 38 when the socket 25 is in its retracted position. When the socket 25 is pressed downwardly to its retracted position against the bias of the spring 41 , it can be rotated so that the protuberances 38 locate in the circumferential grooves 45 and upward sliding is prevented. The first part 18 may be released to move to its extended position by rotating it in the opposite direction so that the protuberances 38 again align with the axially extending grooves 39 so that they may slide there along.

In this second embodiment, the cap 60 and the first part 18 are suitably formed so as to prevent rotational movement of said cap relative to said first part. Thus, rotation of the cap causes the first part to rotate and allows protuberances 38 to align or misalign with the axially extending grooves 39.

Claims

1. An electrical connector adapted to be mounted below a surface of a substrate, which connector comprises a first part having a power output, which first part is movable between an extended position whereat at least part thereof extends beyond the surface of the substrate so that it can supply electrical current to an electrical device to be connected thereto and a retracted position whereat said first part is stowed below the surface of the substrate.

2. An electrical connector as claimed in claim 1 , and further comprising a switch adapted to enable electrical current to pass to the power output, only when said first part is in its extended position.

3. An electrical connector as claimed in claim 2, wherein the switch and the first part are provided in a housing adapted to be mounted in a hole formed in the substrate, the housing defining an internal space extending generally parallel to the axis of the hole and within which the first part is arranged to slide.

4. An electrical connector as claimed in any preceding claim, wherein the first part has an outer periphery on which is provided a seal arranged to sealingly engage the substrate or housing if present.

5. An electrical connector as claimed in claim 3 or claim 4, wherein the housing has an outer end which is provided with an outwardly extending flange arranged to overlie the surface of the substrate around the periphery of the hole.

6. An electrical connector as claimed in any of the preceding claims, wherein the first part is resiliently biased towards its extended position.

7. An electrical connector as claimed in claim 6, wherein there is further provided a catch mechanism adapted selectively to hold said first part in its retracted position.

8. An electrical connector as claimed in any of the preceding claims which further comprises a removable cap arranged to cover an outer end of the first part and protect the power output.

9. An electrical connector as claimed in claim 8, wherein the cap is sized and shaped to fit below the surface, and within the housing if present, when the first part is in the retracted position.

10. An electrical connector as claimed in claim 2 and any of claims 3 to 9 when dependent on claim 2, wherein the first part includes an abutment surface adapted to engage the switch when said first part is in one of its extended and retracted positions thereby to disengage the power supply when said first part is in the retracted position.

11 . An electrical connector as claimed in claim 2 and any of claims 3 to 9 when dependent on claim 2, wherein the switch is provided on the first part and an abutment surface is provided on the substrate or housing and the abutment surface is adapted to engage the switch when said first part is in one of its extended and retracted positions and to disengage the power supply when said first part is in the retracted position.

12. An electrical connector as claimed in claim 2 and any of claims 3 to 9 when dependent on claim 2, wherein the switch includes at least one first electrically conductive contact provided on the first part and at least one second electrically conductive contact provided on the substrate or housing, the first contact being arranged to engage the second contact when said first part is in its extended position.

13. An electrical connector as claimed in claim 3 and any of claims 4 to 12 when dependent on claim 3, wherein the housing extends downwardly beyond a lower surface of the substrate and has a threaded outer surface for receiving a collar.

14. An electrical connector as claimed in claim 2 and any of claims 3 to 13 when dependent on claim 2, wherein there is further provided a power input electrically connected to the switch and the power output and arranged to permit connection to a power source.

15. An electrical appliance having an input connector adapted to connect to a connector as claimed in any of claims 1 to 14.

16. An electrical appliance as claimed in claim 15, wherein the input connector is located on a rear, side or lower surface of the appliance.