GB2077418A

GB2077418A - Electric heaters

Info

Publication number: GB2077418A
Application number: GB8028165A
Authority: GB
Original assignee: United Gas Industries Ltd
Current assignee: United Gas Industries Ltd
Priority date: 1980-05-08
Filing date: 1980-09-01
Publication date: 1981-12-16
Also published as: IE810924L; IE51044B1; GB2077418B; AU519375B3

Abstract

A radiant electric fire has two of its three coil elements 11, 12, 13, regulated by an energy regulator 17. The other, unregulated, element 11 is continuously operated when on/off switch 14 is operated. The energy regulator has a knob 19 whereby different settings can be manually selected. At each setting a different cycle is operated for the regulated elements, for instance, a cycle of 12 seconds on followed by 18 seconds off. <IMAGE>

Description

SPECIFICATION Electric heaters This invention relates to electric heaters of the kind having electrical elements which when energized produce heat.

The invention comprises an electric heater having at least one regulated electrical element connected to be operated through an energy regulator which has at least one selectable setting which, when selected, causes said element to be intermittently operated.

When the element is operated intermittently, the total heat output over a period of time is less than if the element had been operated continuously. The overall long term effect therefore is as though the element had a lower heat output rating. A greater number of heat output settings can therefore be obtained than from an unregulated element.

The electric heater may be a radiant fire having three electric radiant elements, one of which is connected to be operated continuously, and the other two of which are connected to be regulated through the energy regulator.

The three radiant elements may be separately mounted in silica sheaths or may be mounted side-by-side in a single sheath.

Specific embodiments of the invention are now described with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of the heating elements of an electric fire with their controls, and Figure 2 shows another embodiment of heating element means for use in an electric fire.

Referring first to Figure 1, a radiant electric fire comprises a body and a reflector (not shown) in front of which are mounted three 750 watt radiant electric heating bars 11, 12, 13. These are of the silicasheathed coil type having terminals at either end. A double pole switch 44 is manually operable to supply power via leads 15, 15' to the top unregulated element 11, and via leads 16, 16' to an energy regulator 17. The other two regulated heating elements 12 and 13 are connected together at their ends and powered via leads 18, 18' from the output of the energy regulator.

The energy regulator operates electrically on an on/off cyclic basis, the length of time for which the 'on' and 'off' periods last being determined by a rotatable knob 19 having a plurality of different settings, e.g. five settings numbered 0 - 4. The two bars are permanently energized at the highest setting 4, so giving their full potential output of 750 watts each, and at the other end of the scale are permanently off. At settings between these extremes the bars are turned on and off intermittently, for instance 12 seconds on /18 seconds off at setting 1, and 40 seconds on /12 seconds off at setting 3, so that their heat output taken over a period of time is variable between zero and full output. Effectively, the settings 1-3 provide steps of 350 watts increase in overal heat output.The fire is more flexible in use, and may be more economical, since an energy setting can be selected which is closertothe ideal heat output. It will be noted that the upper bar 11 is on continuously when the switch 14 is operated, so that the user is not misled into thinking the fire is turned off during 'off' periods of the cyclic operation of the two lower bars.

The same switch and energy regulator may be used to control the composite heating element means shown in Figure 2. Here, three separate coils 21,22,23 are mounted in a single silica sheath 24 which in cross-section is of oval shape, so that the coils lie side-by-side in a vertical plane. One coil 22, the centre one of the three, is connected, like bar 11 of the Figure 1 embodiment, to be energized all the time that a double pole switch is operated.

The other two coils, 21 and 23, are connected, like bars 12, 13 of the Figure 1 embodiment, to be energized via an energy regulator for variable cyclic periods. With this arrangement the centre coil glows red at all times that the switch is on, the outer coils enhancing the glowing effect and increasing the radiant heat output as selected by the energy regulator.

Another form of radiant heating element (not shown) has two concentric coils, one of larger diameter than the other, within a single circular section silica sheath. The centre coil is connected to be continuously energized, the outer coil being intermittently energized through the energy regulator. The effect here is like a single source heating element which operates at different temperatures.

1. An electric heater having at least one regulated electrical element connected to be operated through an energy regulator which has at least one selectable setting which, when selected, causes said elements to be intermittently operated.

2. An electric heater as claimed in claim 1, wherein said energy regulator has two or more said selectable settings, each setting, when selected, providing a differently timed intermittent operation of the regulated element.

3. An electric heater as claimed in claim 1 or claim 2, in which said energy regulator also has an 'off' setting at which the element is not operated and a full 'on' setting at which the regulated element is continuously operated.

4. An electric heater as claimed in any of claims 1 to 3, in which said setting or one of said settings provides an intermittent operation comprising 12 seconds on and 18 seconds off.

5. An electric heater as claimed in any of claims 1 to 3, in which said setting or one of said settings provides an intermittent operation comprising 40 seconds on and 12 seconds off.

6. An electric heater as claimed in any of claims 1 to 5, comprising a radiant fire and having another radiant element connected to be operated directly through a manual on/off switch, which also directs electrical power to said energy regulator.

7. An electric heater as claimed in any of claims 1 to 6, comprising a radiant fire, and wherein there are two radiant regulated elements connected in parallel to be operated together by said energy regulator.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Electric heaters This invention relates to electric heaters of the kind having electrical elements which when energized produce heat. The invention comprises an electric heater having at least one regulated electrical element connected to be operated through an energy regulator which has at least one selectable setting which, when selected, causes said element to be intermittently operated. When the element is operated intermittently, the total heat output over a period of time is less than if the element had been operated continuously. The overall long term effect therefore is as though the element had a lower heat output rating. A greater number of heat output settings can therefore be obtained than from an unregulated element. The electric heater may be a radiant fire having three electric radiant elements, one of which is connected to be operated continuously, and the other two of which are connected to be regulated through the energy regulator. The three radiant elements may be separately mounted in silica sheaths or may be mounted side-by-side in a single sheath. Specific embodiments of the invention are now described with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of the heating elements of an electric fire with their controls, and Figure 2 shows another embodiment of heating element means for use in an electric fire. Referring first to Figure 1, a radiant electric fire comprises a body and a reflector (not shown) in front of which are mounted three 750 watt radiant electric heating bars 11, 12, 13. These are of the silicasheathed coil type having terminals at either end. A double pole switch 44 is manually operable to supply power via leads 15, 15' to the top unregulated element 11, and via leads 16, 16' to an energy regulator 17. The other two regulated heating elements 12 and 13 are connected together at their ends and powered via leads 18, 18' from the output of the energy regulator. The energy regulator operates electrically on an on/off cyclic basis, the length of time for which the 'on' and 'off' periods last being determined by a rotatable knob 19 having a plurality of different settings, e.g. five settings numbered 0 - 4. The two bars are permanently energized at the highest setting 4, so giving their full potential output of 750 watts each, and at the other end of the scale are permanently off. At settings between these extremes the bars are turned on and off intermittently, for instance 12 seconds on /18 seconds off at setting 1, and 40 seconds on /12 seconds off at setting 3, so that their heat output taken over a period of time is variable between zero and full output. Effectively, the settings 1-3 provide steps of 350 watts increase in overal heat output.The fire is more flexible in use, and may be more economical, since an energy setting can be selected which is closertothe ideal heat output. It will be noted that the upper bar 11 is on continuously when the switch 14 is operated, so that the user is not misled into thinking the fire is turned off during 'off' periods of the cyclic operation of the two lower bars. The same switch and energy regulator may be used to control the composite heating element means shown in Figure 2. Here, three separate coils 21,22,23 are mounted in a single silica sheath 24 which in cross-section is of oval shape, so that the coils lie side-by-side in a vertical plane. One coil 22, the centre one of the three, is connected, like bar 11 of the Figure 1 embodiment, to be energized all the time that a double pole switch is operated. The other two coils, 21 and 23, are connected, like bars 12, 13 of the Figure 1 embodiment, to be energized via an energy regulator for variable cyclic periods. With this arrangement the centre coil glows red at all times that the switch is on, the outer coils enhancing the glowing effect and increasing the radiant heat output as selected by the energy regulator. Another form of radiant heating element (not shown) has two concentric coils, one of larger diameter than the other, within a single circular section silica sheath. The centre coil is connected to be continuously energized, the outer coil being intermittently energized through the energy regulator. The effect here is like a single source heating element which operates at different temperatures. CLAIMS

8. A radiant electric fire as claimed in claim 6 or claim 7, wherein said other radiant element is combined with the regulated radiant element or elements in a common silica sheath.

9. A radiant electric fire as claimed in claim 8, wherein said other radiant element is located parallel to said regulated element or elements.

10. A radiant electric fire as claimed in claim 8, wherein said other radiant element is a coil arranged concentrically with said regulated element or elements.

11. A radiant electric fire substantially as described hereinbeforewith reference to Figure 1 orto Figure 2 of the accompanying drawings.