GB2408569A - A domestic heating appliance controlled by a touch sensitive element - Google Patents

Abstract

A domestic electric or gas heating appliance having a plurality of modes of operation, has a touch-sensitive control element 22 operative for changing between the modes. The element may be of the capacitance type formed by a conductive surround (14, fig 1); by sensing body warmth; or by contact to close a circuit. Discreet touches may be counted in a counter 23 to invoke particular modes. The modes may be simply on/off, or on/off combinations of a heater, fan, flame effect and lighting. A remote control having a releaseable fastening (121, fig 5) such as a plug or crocodile clip, and a contact plate (123, fig 5) may be provided. Circuits with Schmitt trigger NOT gates, a clock and D-type flip-flops (fig 3) or with triacs (fig 4) disclosed.

Description

PATENTS ACT 1977 MNS/MDH/A10984GB Title: Heating Apparatus

Field of the Invention

The present invention relates, in broad terms, to the general field of heating apparatus, such as those found in domestic environments, to heat an interior living space, for example. More specifically, but by no means exclusively, the invention relates to electric heating appliances having several modes of operation.

Background to the Invention and Overview of the Prior Art Electric heating appliances of this type are well known, particularly where the appliance is installed domestically, as an alternative to an open (real) fire. The modes of operation may relate to the heating properties of the appliance, or they may be purely decorative, in that flame-simulating effects are provided, for example. A heating appliance may thus have a heating part, a fan to force air over the heating part and around a room in which the heating appliance is installed, a lighting part to illuminate the appliance and a flame effect part to simulate the appearance of flames in the appliance, and to provide a pleasing visual effect. The different functional parts of the heating appliance are often independent of each other and operable separately, so that, for example, the fan may be operated without the heating part to cause unheated air to circulate around a room, or the heating part and the fan may be operated without the flame-effect part to heat a room, when the decorative effect of-the appliance is not required. A typical such device is known from our earlier UK patent, No. 2325733B.

A disadvantage of such prior art arrangements is that, because of the independent operability of the different parts, they have a plurality of controls, such as switches, knobs and the like, whereby the various functions can be controlled. Such arrangements can sometimes be inconvenient, in that in order to achieve a desired mode of operation of the appliance, a user may have to operate two or more controls, which can be difficult, especially for elderly and partially-sighted people, for example.

Because such appliances are often decorative as well as functional, the controls are often unattractive and hidden in locations which may not be readily apparent or easily accessible, such as the bottom or side wall of the appliance, so as not to detract from the appearance of the appliance. Users whose movement is impaired, such as the elderly or disabled, can sometimes have difficulty in reaching and operating the controls.

According to a first aspect of the present invention, there is provided a heating appliance having a plurality of modes of operation, the appliance having a touch-sensitive control element operative to effect a change between the modes.

The control element may be associated with a counter responsive to sequential input signals which are indicative of a contact part being touched, the mode of operation of the appliance varying in accordance with the number of instances in which the contact part is so touched.

Thus, the mode of operation may vary in accordance with a value stored within, connected to or otherwise associated with the counter.

The appliance may comprise a plurality of switching elements, each being operable to control a circuit, such that at least one of a plurality of circuits may be operable in accordance with the counter value.

The switching elements may include eleckically-operable switches, relays and semiconductor devices.

The circuits may be independent of one another and may include a heating circuit part, a fan circuit and a flame-effect circuit.

The contact part may be provided as an integral part of the appliance, such as part of a housing or trim. Additionally or alternatively, the contact may be remote from the body and may be in the form of one or more elements such as plates connected to the switching element, perhaps by a wire. Some of the benefits of such remote operation might be: To aid the disabled, who may not be able to reach the contact part on the housing or Him of the appliance To allow control of the appliance from any desired remote position If there is a risk from children or pets (for example) touching the housing of the appliance and inadvertently turning the appliance on, the contact on the housing of the appliance could be disconnected and the remote contact connected. The touch control capability of the appliance could then be solely by means of the remote plate, for example, which can be positioned out of reach of pets and children.

The contact part may be releasably attached to the appliance.

The heating appliance may be electrically powered, conveniently by mains power.

According to a second aspect of the present invention, there is provided a heating appliance having a plurality of modes of operation, the appliance having a control element and a counter, the counter being responsive to sequential input signals, and operative to vary the mode Of operation in accordance with the number of signals counted.

The invention, in its second aspect, may comprise one or more features set out in the preceding paragraphs.

According to a third aspect of the present invention, there is provided a touch-sensitive control element for a multi-modal heating appliance, whereby different modes of operation of the appliance may be invoked by touching a contact part of the element.

The invention, in its third aspect, may comprise one or more of the features set out in the preceding paragraphs.

According to a fourth aspect of the present invention, there is provided a remote control device for a heating appliance, the device having a touchsensitive contact part and a connection element whereby the device may be releasably attached to the appliance, where a remote mode of operation is desired.

According to a fifth aspect of the present invention, there is provided, in combination, a heating appliance having a plurality of modes of operation and a remote control device therefor, the remote control device having a touch- sensitive contact part whereby different modes of operation may be invoked.

The invention, in its fifth aspect, may comprise one or more of the features set out in the preceding paragraphs.

It should be understood that all embodiments of the invention featuring the touch sensitive control capability and switching element may be used in addition to (prior art) manually-operated switches and/or an electronic remote control component such as an infrared remote control.

Specific and non-limiting embodiments of the invention will now be described, strictly by way of example only, with reference to the accompanying drawings, in which: FIGURE 1 is a perspective view of a domestic electric fire; FIGURE 2 is a functional block diagram of an electrical circuit used to control the fire of Figure 1; FIGURE 3 shows an electrical circuit used to control the fire of Figure 1; FIGURE 4 shows an alternative electrical circuit; FIGURE 5 shows a remote control device for optional use in conjunction with the fire of Figure 1; and FIGURE 6 shows a further alternative electrical circuit, concerning a touch switch operation.

Referring first to Figure 1, there is shown a heating appliance in the form of a domestic electric fire 10 having a housing 11 which contains, in generally conventional manner, a heat-generating part (not shown) in conjunction with a simulated solid fuel arrangement 12 which is lit, from beneath and from the rear, so as to provide an aesthetically-pleasing simulated fuel and flame effect. A fan (not shown) is provided, within the housing 11, to blow heated air out through a front vent 13 so that the room in which the fire is installed may be heated, by convection.

The fire 10, in this example, is mains powered, and can operate in one of a plurality of different modes, depending upon whether it is desired, for example, to blow cold (i.e. unheated) air into the room, or to provide a heating effect, and whether or not a simulated flame appearance is required. Although the specific modes of operation do not form a central part of the present disclosure, it will be understood, in line with otherwise conventional electric fires, that variable fan speeds may be available and that variations in the simulated flame arrangement may also be effected.

The housing 11 is provided with a surround 14, formed from an electrically-conductive material such as a metal, alloy or the like. For aesthetic reasons, the surround, in this example, is formed from brass, but it will be understood that a wide variety of other materials will also be suitable.

The conductive surround 14 serves as a contact part of a touch-sensitive control element (see Figures 2, 3 and 4) that is operative to effect changes between the various modes of operation discussed above.

As explained in greater detail with reference to Figures 3 and 4, the touch-sensitive arrangement, in this example, is of the capacitance-type, relying on the increase in overall capacitance that is provided when a person makes contact with the conductive surround 14. It will be understood that the use of a readily accessible, visible and touchsensitive arrangement of this type greatly facilitates operation of the fire and provides real and tangible advantages for it elderly or disabled people, for example, who might otherwise have difficulty in locating and operating control knobs and switches, which, for aesthetic reasons, are often hidden from view. The removed requirement of readily-accessible controls also allows enhanced design and aesthetic flexibilty, for appliances (such as domestic heating appliances) where a pleasing appearance is important.

It will also be understood, of course, that the touch-sensitive capability may alternatively be provided by other means, such as sensing the relative warmth of the human body, by detecting the increased "antenna" effect that is provided, when a person makes contact with the conductive surround, or perhaps by allowing a person's finger to close a circuit, by providing two closely-spaced contacts, at at least one position on the housing 11, the surround 14 or elsewhere.

At its simplest, the touch-sensitive control element may be operative to turn on/turn off the fire, with an "on" condition giving rise to a heating effect and an aesthetically-pleasing simulated flame arrangement. However, the applicants envisage that a more sophisticated degree of control may be desirable, with the control element thus being operative to invoke different modes of operation on a sequential touch basis. To the user, the effect is that repeated, discrete touches of the conductive surround 14 will pass appropriate signals (conveniently electrical) to a counter which, in turn, is operative to invoke a mode of operation in accordance with a given counter value. In effect, therefore, the control element cycles through a pre-set sequence of modes of operation, with each subsequent user touch effecting a counter increment which, in turn, changes the resulting mode of operation.

Referring next to Figure 2, there is shown a functional block (and hence simplified) diagram of an electrical circuit 20 used to control the fire of Figure 1, having a transformer 21, a touch-sensitive contact part 22, a counter 23, a switching part 24 and a plurality of independent operational parts including a heating part 25, a fan 26, a flame effect part 27 and a lighting part 28.

The transformer 21 takes alternating current (AC) from a supply, such as a domestic mains outlet, and converts it into a DC supply voltage usable by the S other parts of the appliance. The touch-sensitive contact 22 has an output at which an electrical signal is generated each time the touchsensitive contact 22 is touched. An input of the counter 23 is connected to the output of the contact 22. The counter counts the number of electrical signals received at its input, corresponding to the number of times the contact 22 has been touched. A representation of this number is produced at an output of the counter 23. The switching part 24 is connected to the output of the counter 23, and operates one or more of the plurality of independent AC circuits, according to the output of the counter 23. Thus, the mode of operation of the electric fire is determined by the number of times the contact 22 is touched, in a given cycle.

Turning next to Figure 3, there is shown a schematic (and more detailed) circuit diagram for the circuit 20 which may be used to control the electric fire.

It will be understood, of course, that this and the other circuit diagrams shown herein are merely illustrative of some, preferred, ways of putting the invention into practice. Other circuit arrangements are thus envisaged and possible.

The circuit 20 includes a transformer part, shown generally at 30, a touch-sensitive part, shown generally at 40, a counting part, shown generally at 50, and a switching part, shown generally at 60.

The transformer part 30 includes a transformer 31 having two terminals 3 la and 3 lb to which mains AC electricity can be supplied, a bridge rectifier 32 composed of four diodes 32a - 32d, smoothing capacitors 33, 34 and 36 and a voltage regulator integrated circuit 35. These components are connected in a generally conventional manner so as to produce a regulated DC supply voltage VDD, to power the rest of the circuit 20. The transformer part 30 further includes a resistor 37, a capacitor 38 and a transistor 39, connected in a generally conventional fashion so as to produce a DC voltage VDD2 which is slightly lower than VDD.

The touch-sensitive part 40 is powered by the transformer part 30, and includes an electrically-conductive contact element 41 made of copper or any other suitable electrically-conductive material, resistors 42 and 45, Schmitt trigger NOT gates 43 and 47, a diode 44 and a capacitor 46. The electrically- conductive element 41 forms an input to the touch sensitive part 40, and an output of the Schmitt trigger NOT gate 47 forms an output of the touch sensitive part 40. The touch-sensitive part, in this example, is located on a main body of an electric heating appliance, for example as a part of a decorative surround, as shown in Figure 1.

The Schmitt trigger NOT gates 43 and 47 each have an input and an output, with the voltage at the output being at logic 0 (that is, at or close to 0 volts) when the voltage at the input is above an upper threshold level. The voltage at the output remains at logic 0 until the voltage at the input falls below a lower threshold, whereupon the voltage at the output changes to logic 1 (that is, at or close to the supply voltage VDD).

When the conductive contact element 41 is not engaged, i.e. is not being touched, the input of Schmitt trigger NOT gate 43 is connected to 0 volts by the resistor 42. As this is below the lower threshold of NOT gate 43, the output of NOT gate 43 is at logic 1. There is therefore no potential difference across the diode 44, so capacitor 46 quickly charges up through resistor 45. As soon as capacitor 46 has charged up to a point where the voltage across it is above the upper threshold of Schmitt trigger NOT gate 47, the output of NOT gate 47 changes to logic 0, and remains at logic 0 until the voltage at its input drops below its lower threshold. Thus, when the conductive element 41 is not being touched, the output of the touch-sensitive part 40 is at logic 0.

When the electrically-conductive element 41 is operated, i.e. when it is touched by a person, the person's body acts as a capacitor, adding to the overall capacitance of the system. The person's body quickly charges through resistor and capacitor 46, until the voltage at the input of Schmitt NOT gate 43 is greater than the upper threshold of NOT gate 43. The output of NOT gate 43 changes to logic 0, and there is thus a potential difference across diode 44, which conducts. Capacitor 46 discharges and the voltage at the input of NOT gate 47 changes to logic 0, causing the output of NOT gate 47 to change to logic 1. As soon as the output of NOT gate 43 changes to logic 0, the body of the person touching the electrically-conductive element 41 quickly discharges through resistor 42. This causes the voltage at the input of NOT gate 43 to drop, and as soon as it drops below the lower threshold of NOT gate 43, the output of NOT gate 43 changes to logic 1, causing the output of NOT gate 47 to change to logic 0, as described above. Thus, when a person touches the electrically- conductive element 41, the output of the touch-sensitive part 40 momentarily changes to logic 1.

It is to be understood that there is no risk of a person touching the electrically-conductive element 41 receiving an electric shock, since the electrically-conductive element 41 is electrically isolated from the mains electricity supply by the transformer part 30, and any electric current flowing as a result of touching the electrically-conductive element 41 is likely to be of the order of a few microamps only.

The counting part 50 is based upon a decade counter integrated circuit (IC) 51. The counter IC 51 has ten outputs Q0 - Q9 denoted by the reference numerals 56a - 56j, each representing a different number in the range 0 - 9.

Thus, the output Q0 56a represents zero, Q1 56b represents one and so on. The counter IC 51 also has a 'carry out' output 57, which is not used in this circuit.

The counter IC 51 has three inputs, 'clock' 53, 'clock enable 54' and 'reset' 55, as well as power supply connections.

In order for the counter IC 51 to function as a counter, the 'clock enable' input 55 must be at logic 0, and thus in this circuit, it is connected to 0 volts.

The counter IC 51 counts positive-going electrical signals, that is signals whose voltage is going from logic O to logic 1, detected at its 'clock' input 53, and sets the corresponding QO - Q9 output 56a - 56j to logic 1. Thus, when power is first applied to the counter IC 51, no logic 1 electrical signals have been detected at its 'clock' input 53, and thus the QO output 56a is set to logic 1. If a positive-going signal is subsequently detected at the 'clock' input 53, the counter resets the QO output 56a to logic 0 and sets the Q1 output 56b to logic 1, thus to represent a count of 1. The next positive-going signal detected at the clock' input 53 will cause the Q2 output 56c to be set to logic 1, while the Q1 output 56b will be reset to logic 0, and so on. If a tenth positive-going signal is detected at the 'clock' input 53, the counter IC 51 resets itself, setting the QO output 56a to logic 1 and the Q 1 - Q9 outputs 56b - 56j to logic 0.

The counter IC 51 can also be reset by setting the 'reset' input 55 to logic 1. This resets the counter IC, causing the QO output 56a to be set to logic 1 and the Q1 - Q9 outputs 56b - 56j to be set to logic 0, whatever the state of the inputs and outputs prior to setting the 'reset' input 55 to logic 1.

The 'clock' input of the counter IC 51 is connected to the output of the touch-sensitive part 40, thus to count the number of instances of operation of that part, i.e. the number of times the electricallyconductive element 41 has been touched. The QO and Q4 outputs 51a, 51e are connected to the 'reset' input to cause the counter IC 51 to reset on a count of 0 or 4. A pull-up resistor 52 is connected in a generally conventional manner to the QO and Q4 outputs 56a, 56e and the 'reset' input 55, to ensure that the counter IC 51 resets correctly on a count of O or 4. The Q1 - Q3 outputs 56b - 56d are connected to elements of the switching part 60.

The switching part includes D-type flip-flops 61a - bid, each having a Preset' (PR) input 62a - 62d, a 'Data' (D) input 63a - 63d, a 'Clock' (CLK) input 64a - 64d and a 'Clear' (CLR) input 65a - 65d. Each of the Dtype flip flops 61a - 61d also has a 'Q' output 66a - 66d and a 'not Q' output 67a - 67d, each 'not Q' output 67a - 67d being the logical inverse of the corresponding Q' output. The logic level of a Q output 66a - 66d changes when both the corresponding D input 63a - 63d and CLK input 64a 64d are at logic 1. Thus, if, for example the Q output 66a of D-type flipflop 61a is initially at logic 0, it will change to logic 1 when both D input 63a and CLK input 64a are at logic 1.

The Q output 66a will change back to logic 0 when D input 63a is next at logic 1 and the CLK input 64a is at logic 1.

Each of the PR inputs 62a - 62d of the D-type flip-flops 61a - 61d is connected to the positive supply voltage VDD. This is a requirement to allow the flip-flops 61a - 61d to function correctly. The D inputs 64a 64d ofthe flip flops 61a - 61d are each connected to a different output, Q1 - Q4 56b - 56d of the counter IC 51, in order that each Q output 66a 66d of the D-type flip-flops 61a - 6 id may change according to the number of instances of operation of the touch-sensitive part 40, i.e. the number of times the electrically- conductive element 41 has been touched.

Each of the CLK inputs 64a - 64d of the D-type flip-flops 61a - 61d is connected to a 'Q' output 69a - 69d of a flip-flop 68a - 68d, each of which has an 'A' input 70a - 70d connected to the same Q1 - Q4 output 56b - 56d of the_ counter IC 51 as the D input 63a - 63d of the corresponding D-type flip-flop 61a - bid. This ensures that, when a Q1 - Q3 output 56b 56d of the counter IC Sl changes, causing the logic level of the D input 63a - 63d connected thereto to change, the CLK input 64a - 64d is at logic 1, causing the corresponding Q output 66a - 66d to change. Thus, if the electrically conductive element 41 has been touched once, for example, the Q1 output 56b of the counter IC 51 is at logic 1. The D and CLK inputs 63a, 64a of D-type flip-flop 61a are both at logic 1, so the Q output 66a of flip-flop 61a changes to logic 1.

The CLR inputs 65a - 65d of each of the D-type flip-flops 61a - 61d are connected, via NOT gate 56 to the Q0 and Q4 outputs 56a, 56e of the counter IC 51 so that each of the Q outputs 66a - 66d of the D-type flipflops 51 a-5 1 d resets to logic O when the counter IC 51 is reset.

Each of the Q outputs 66a - 66d of the D-type flip-flops 61a - 61d is connected, in a generally conventional manner to an electromagnetic relay (not shown) to control an independent AC circuit of a functional part, such as heating part, a fan, a lighting part or a flame-effect part, of the electric fire.

Thus, the mode of operation of the heating appliance is controlled by the number of instances of actuation of the touch-sensitive part 40.

Turning now to Figure 4, there is shown an alternative schematic circuit lO diagram 70 for a circuit which may be used to control the electric heating appliance. The circuit 70 includes a transformer part shown generally at 80, a touch-sensitive part, shown generally at 90, a counting part shown generally at lOO and a switching part shown generally at l lO.

The transformer part 80 is operative to supply a partially rectified DC l S supply voltage to those parts of the circuit 70 which require a DC supply.

The touch-sensitive part 90 operates in a similar fashion to the touch sensitive part 40 shown in Figure 3.

The counting part l DO includes two cascaded flip-flops, shown generally at 101 and 102, made from discrete components. The flip-flops 101 and 102 count the number of instances of operation of the touch-sensitive part 80. Each of the cascaded flip-flops 101, 102 has an output which is connected to the switching pert 110.

The switching part includes two triacs 101, 102. Each triac controls an independent separate AC circuit of a functional part, such as a heating part, of an electric heating appliance. A gate terminal of each triac 101, 102 is connected to one of the outputs of the cascaded flip-flops 101, 102, such that the operation of the AC circuits depends upon the number of instances of operation of the touch-sensitive part 90. Although the schematic circuit diagram of Figure 4 only shows 2 triacs, each controlling an independent AC circuit, it l will be understood by those skilled in the art that it would be readily possible to modify the circuit 70, for example by adding further cascaded flip-flops, such that the mode of operation of more than two independent AC circuits could be controlled.

In a still further alternative embodiment, the touch-sensitive part may be replaced by an actuating part such as a simple push switch to provide electrical signals to the counter, and thus to control the operational parts of the appliance.

It will be appreciated by those skilled in the art that such a modification could be easily accomplished, with the "counting" capability and "mode-cycling" l O operation still being retained.

Referring next to Figure 5, this shows a remote control device for optional use, in conjunction with an electric fire such as that shown generally in Figure 1. Whilst the provision of a touch-sensitive surround offers many advantages over prior art constructions, fires of this general type are typically located at a relatively low position, meaning that some people, such as the infirm or elderly, may have difficulty in reaching down to effect a change in the mode of operation, or to turn off the fire, for example. Such problems may be alleviated, at least in part, by the use of a remote control device, which, in effect, moves the touch- sensitive contact closer to a seated user, for example, thus obviating the requirement for that user to move towards, and bend down over, the fireplace, to adjust the operational mode. The provision of a remote control device (illustrated generally at 120) also provides safety benefits, in that the connection of the device to a conductive part of the appliance, by way of a releasable connector 121 (such as a plug, terminal or crocodile clip, for example) may result in the hitherto operative surround becoming insulated and thus ineffective to change the mode of operation of the fire. This could be advantageous in reducing accidental operation of the fire, such as by a small child or animal, for example, with it only being possible to turn on the fire and change the operational mode by effecting a contact with the distal end 122 of the device 120, that is provided with a conductive (e.g. metal) contact plate

123, for example.

It will nonetheless be appreciated that attachment of the remote control device to the appliance may not necessarily result in the insulating effect described above, with it being conceivable that touching either the flat metal plate or the conductive surround 14 could result in a change in operational mode.

Referring lastly to Figure 6, an alternative implementation of a touchsensitive control is shown.

Touch Switch Operation ICla - d form two oscillators (Clock 1 & Clock 2), the outputs of which are fed into IC2a and IC2b (frequency comparator). Clock 2 is set to 20 KHz by virtue of the external timing components R2, R3 & C3. Clock 1 has an external input via C1 which is connected to the appliance housing, trim and/or to a remote touch plate. The frequency of Clock 2 is set to 20KHz with the external connection made. Adjustment is by VR1.

When finger contact is made with the appliance trim, Clock l's frequency is pulled lower than the initial setting of 20KHz.

IC2a, IC2b IC3a & IC4a form a frequency comparator. The outputs of Clock 1 and Clock 2 are fed into two D-type flip-flops (triggered by the leading edges).

The flip-flops' outputs are compared by an AND gate. If the output of the AND gate becomes "1", the flip-flops are reset. If the frequency of F1 is higher than the frequency of F2, the signal "Q2" consists of needles and "Q1" is a pulse train. Therefore, the energy content of Q 1 is higher than that of Q2. Q 1 and Q2 come via a low-pass filter (consisting of R4, R3 and C4) and are compared by an analogue comparator circuit (IC3). For the case when the frequency of F 1 is lower that the frequency for F2, the signal Q1 consists of needles and Q2 a pulse train.

The output from IC4a is fed into IC3b (connected as a buffer) and stray pulses removed by C5. IC 1 e inverts the output level prior to being fed into IC6 clock input. The output of ICle will be logic '['when finger contact is made with the

appliance trim and '0' when no contact is made. This output increments counter IC6.

Although, in the foregoing examples, the touch control operation has been illustrated in conjunction with an electrically-operable heating appliance, it is envisaged, by the applicants, that the touch control capability might also be applicable to other heating appliances such as domestic gas fires, for example.

Evidently, in the case of gas fires, it is less likely that a flame effect generator will be required, although it is nonetheless envisaged that changes between flame states (corresponding to different levels of heat output) might be effected by invoking a touch control operation. In view of the temperature at which domestic gas fires can sometimes operate, it is likely that it will be preferable to provide the touch-sensitive contact part at a position remote from the main body of the fire.

It is also envisaged that it may be desirable to provide a separate fire surround that is integral with or is provided with a remote touchsensitive contact part, to enable a separate fire to be operated in a remote, touch-sensitive manner. To that end, appropriately equipped fire surrounds may be provided, having a touch-sensitive part that is operative, via a connecting wire or the like, to effect a change in a mode of operation of a separately acquired/separately installed fire, to which the connection is attached. In the case of a wooden fire surround, an appropriately-coloured touch plate could be provided on an upper or side part of a mantel or mantelpiece, for example.

In the present specification "comprises" means "includes or consists of" and "comprising" means "including or consisting of". l

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims (19)

1. A heating appliance having a plurality of modes of operation, the appliance having a touch-sensitive conko1 element operative to effect a change between the modes.

2. A heating appliance according to claim 1 wherein the conko1 element is associated with a counter, responsive to sequential input signals which are indicative of a contact part being touched.

3. A heating appliance according to claim 2 wherein the mode of operation of the appliance varies in accordance with the number of instances in which the contact part is so touched.

4. A heating appliance according to claim 2 or claim 3 wherein the mode of operation varies in accordance with a value stored within, connected to or otherwise associated with the counter.

5. A heating appliance according to claim 4 wherein the appliance comprises a plurality of switching elements, each being operable to control a circuit, such that at least one of a plurality of circuits may be operable in accordance with the counter value.

6. A heating appliance according to claim 5 wherein the switching elements include electrically-operable switches, relays or semiconductor devices.

7. A heating appliance according to claim 5 or claim 6 wherein the circuits are independent of one another.

8. A heating appliance according any one of claims 2 to 7 wherein the contact part is provided as an integral part of the appliance.

9. A heating appliance according to any one of claims 2 to 7 wherein the contact part is remote from the appliance.

10. A heating appliance according to any one of claims 2 to 9 wherein the contact part is releasably attachable to the appliance.

11. A heating appliance having a plurality of modes of operation, the appliance having a control element and a counter, the counter being responsive to sequential input signals, and operative to vary the mode of operation in accordance with the number of signals counted.

12. A touch-sensitive control element for a multi-modal heating appliance, whereby different modes of operation of the appliance may be invoked by touching a contact part of the element.

13. A remote control device for a heating appliance, the device having a touch-sensitive contact part and a connection element whereby the device may be releasably attached to the appliance, where a remote mode of operation is desired.

14. An electric heating appliance substantially as hereinbefore described and/or as shown in the accompanying drawings.

15. A touch-sensitive control element for a multi-modal heating appliance, substantially as hereinbefore described and/or as shown in the accompanying drawings.

16. A remote control device for a heating appliance substantially as hereinbefore described and/or as shown in the accompanying drawings.

17. A domestic electric fire substantially as hereinbefore described and/or as shown in the accompanying drawings.

18. A heating appliance having a plurality of modes of operation and a remote control device therefor, the remote control device having a touch sensitive contact part whereby different modes of operation may be invoked.

19. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.