GB2227378A

GB2227378A - Lampholder adaptor with switched dimmer control

Info

Publication number: GB2227378A
Application number: GB8926820A
Authority: GB
Inventors: Robert Keller
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-11-29
Filing date: 1989-11-28
Publication date: 1990-07-25
Also published as: GB8827880D0; GB8926820D0

Abstract

A lamp adaptor has a plug 3 that can be inserted into a conventional lampholder 8 and defines a socket 1 into which a conventional lamp 10 can be inserted. An electronic circuit (fig 3 not shown) controls the supply of power from the lampholder to the socket in response to a user contacting a touch sensitive terminal 7 which is in the form of a wire extending from the adaptor body 2. The circuit may switch the lamp on/off or dim the lamp in response to touching the terminal 7. <IMAGE>

Description

LAMP ADAPTOR The present invention relates to a lamp adaptor, and in particular to a lamp adaptor which can be inserted in a conventional lampholder and can receive a conventional lamp.

Fixed ceiling and wall lights are generally controlled by wallmounted mechanical switches. If it is desired to arrange for such lights to be controllable by touch-sensitive switches, it is a simple matter to replace the existing mechanical wall switches with appropriate electronic touch-sensitive switches. Such electronic switches may be simple on/off devices, or may enable dimming (variation in intensity) of the controlled lights.

Table lights and "standard" lights generally incorporate mechanical on/off switches which are manually accessible. It is not possible however to adjust the switches to dim the intensity of illumination, nor is it possible to easily replace the existing switches with touch-sensitive dimmer switches. Thus in practice it is unusual to find a dimmable table or standard lamp.

Some wall lights incorporate local switches which enable the lights to be turned off even if power is being supplied to the lamp unit from a main switch. It is not possible to easily adapt most wall light devices to incorporate switches however, and many wall lights are not easily accessible for any such switches to be actuated.

Lamp adaptors are known which comprise a body defining a socket for receiving a lamp and an end portion for insertion into a lampholder, a mechanical switch being provided to control the supply of power from the lampholder to the lamp. Such adaptors cannot provide dimming and in many circumstances it is very difficult to operate the switch as the adaptor is not readily accessible to a user's hand.

It is an object of the present invention to obviate or mitigate the above problems.

According to the present invention, there is provided a lamp adaptor comprising an electrically insulating body, a terminal supporting socket defined by the body for receiving a lamp bulb, a terminal supporting end portion defined by the body for insertion into a lamp holder, and means housed within the body for electrically connecting the socket terminals to the end portion terminals such that power can be s'pj 2 . amp supported in the socket from a lampholder in which the end portion is supported, wherein the connecting means comprises an electronic circuit incorporating an input terminal that may be contacted by a user, the electronic circuit being operative to control the supply of power to the said lamp in response to a user contacting the input terminal.

The input terminal preferably comprises an elongate flexible wire extending from the body, the wire being insulated except at its end remote from the body. This arrangement is particularly advantageous as the wire (which could be cut to a convenient length) hangs down and is readily accessible when used with either ceiling, wall, table or standard lights.

Preferably the electronic circuit provides the capacity to dim a lamp plugged into the socket.

An embodiment of the present invention will now be described, by way of an example, with reference to the accompanying drawings, in which: Fig. 1 illustrates an embodiment of the invention; Fig. 2 shows the adaptor of Fig. 1 fitted to a table light; and Fig. 3 is a schematic block diagram of the circuitry of the adaptor of Fig. 1.

Referring to Fig. 1, the lamp adaptor consists of a lampholder 1 supported an insulated moulding 2 to which is attached a bayonet cap fitting 3. The fitting 3 is conventional and may be plugged into a conventional lampholder.

An electronic dimming circuit is contained within the moulding 2 and electrically connected to terminals of the fitting 3 and of the lampholder 1. A neon indicator 4 serves as a location aid in the dark, and also as a "mains on" indication. The lampholder 1 is provided with a shade retainer, and in use receives a standard wattage lamp.

A socket 5 is fitted to moulding 2, and receives a plug 6 to which is attached a length of single core insulated conductor 7. The end of the conductor 7 is exposed so that it can be touched by a user.

Fig. 2 shows the adaptor in situ, plugged into a lampholder 8 of a table light 9. A lamp lG is fitted to lampholder 1. A lamp shade which in use is mounted on the lamp is not shown.

In order for the adaptor's electronic dimming circuit to function, the existing ampho'dcr r s live (L) terminal must contact the correct terminal of bayonet cap 3, i.e. if the lamp is non-functioning, the adaptor should be rotated 180 degrees, so that the other terminal of bayonet cap 3 will make contact with the live connection of the lampholder 8 when inserted.

Fig. 3 illustrates the circuitry of the electronic dimming circuit.

The input terminal wire 7 is connected to an integrated circuit dimmer 11, e.g. a circuit type SLB 0586 (available from Siemens) or an equivalent. This circuit is specifically designed for the phase control of lighting from a touch sensor input. The dimmer circuit 11 is mounted in the body 2 and may be provided with programming links 12 and a sensitivity control 13 (not shown in Figs. 1 and 2). The programming links determine the response of the circuit to a user contacting the wire 7 (e.g. touches of less than one second turn the lamp on and off, whereas longer contact will adjust the lamp brightness). The sensitivity control is adjustable by the user to provide a desired response given the length and size of the wire 7.

The circuit 11 produces trigger pulses on output 14 which control a lamp switching circuit 15 connected in series with the lamp 16 to be controlled.

Thus, wire 7 is used to remotely control the lamp functions in response to the user touching its un-insulated end. If the end of the wire is placed in electrical contact with a conducting medium, such as water or damp soil, or a conductive metal lampshade frame, then touching that conducting medium will also control the lamp functions.

In use, minute 50Hz signals are injected into the conducting medium, or directly into the wire 7, from a persons touch. These signals are connected, via plug 6 and socket 5, to the sensor input of the electronic dimming circuit. The operation of the dimming circuit in response to the signals is entirely conventional and therefore is not described in further detail herein.

In the above-described embodiment, the end of the wire 7 is described as being uninsulated. In practice however the system can be operated without any portion of the wire being uninsulated. Simply by contacting the insulated wire a user's body is capacitively coupled to the control circuit so as to enable the control of the lamp, assuming that an appropriate circuit sensitivity is provided. Such an arrangement has the advantage that the user can control the circuit by contacting the wire at any position along its length rather than having to contact the wire end. It also makes it possible to connect the control wire to extension wires distributed in a way that enables the lamp to be controlled from a variety of different positions.

Claims

1. A lamp adaptor comprising an electrically insulating body, a terminal supporting socket defined by the body for receiving a lamp bulb, a terminal supporting end portion defined by the body for insertion into a lamp holder, and means housed within the body for electrically connecting the socket terminals to the end portion terminals such that power can be supplied to a lamp supported in the socket from a lampholder in which the end portion is supported, wherein the connecting means comprises an electronic circuit incorporating an input terminal that may be contacted by a user, the electronic circuit being operative to control the supply of power to the said lamp in response to a user contacting the input terminal.

2. A lamp adaptor according to claim 1, wherein the input terminal comprises an elongate flexible wire extending from the body.

3. A lamp adaptor according to claim 2, wherein the elongate flexible wire is insulated except at its end remote from the body.

4. A lamp adaptor according to claim 1,2 or 3, wherein the electronic circuit is switchable by a user contacting the input terminal to an off condition, a fully on condition, on one or more dimmed conditions in which the level of power supplied is reduced relative to the fully on condition.

5. A lamp adaptor substantially as hereinbefore described with reference to the accompanying drawings.