Fire extinguishing arrangement

Abstract

A fire extinguishing arrangement for integration into a domestic clothes dryer, washing machine, refrigerator, freezer, fridge-freezer or dishwasher. The fire extinguishing arrangement has a fire extinguisher that is sized and shaped to be set in the free internal space around the inner workings of a domestic clothes dryer, washing machine, refrigerator, freezer, fridge-freezer or dishwasher. The fire extinguishing arrangement further has a trigger mechanism that is operable to trigger the fire extinguisher to release an extinguishant, a heat detector capable of operating the trigger mechanism when pre-set temperature is reached. The heat detector is further placeable at a remote location to the fire extinguisher. The fire extinguishing arrangement also can also break an electrical circuit (e.g. to cut the power source to the appliance) when the heat detector detects a pre-set temperature.

Claims

1. A fire extinguishing arrangement for integration into a washing machine, the washing machine being powered by an electrical supply, the fire extinguishing arrangement comprising: a fire extinguisher that is sized and shaped such that it can be set in the free internal space around the inner workings of the washing machine; a trigger mechanism that is operable to trigger the fire extinguisher to release an extinguishant; at least one heat detector capable of operating the trigger mechanism when a pre-set temperature is reached, the at least one heat detector being placeable at a remote location to the fire extinguisher, and; the fire extinguishing arrangement comprising a means for stopping the electrical supply when the at least one heat detector detects a pre-set temperature, and wherein the trigger mechanism comprises an activator means for activating the extinguisher to release the extinguishant, and an operating means that operably connects the at least one heat detector to the activator means and wherein forces are exchangeable between the activator means and the at least one heat detector via the operating means, the operating means comprising an inner cable and at least one sleeve, the inner cable extending through the at least one sleeve, wherein the at least one sleeve is retained in a predetermined position relative to the inner cable by the at least one heat detector and upon detection of fire by the at least one heat detector, the at least one sleeve is released and can move relative to the inner cable, the trigger mechanism being configured to trigger the fire extinguisher upon movement of the at least one sleeve relative to the inner cable.

2. The fire extinguishing arrangement as claimed in claim 1, comprising at least one urging means for urging the at least one sleeve of the operating means against a structure and wherein the at least one heat detector is operably integrated with the at least one urging means, and the at least one heat detector and the at least one urging means operate together to retain the at least one sleeve in a predetermined position relative to the inner cable.

3. The fire extinguishing arrangement as claimed in claim 2, wherein the at least one urging means comprises a first component and a second component wherein each component is capable of engaging with the at least one sleeve and moving the at least one sleeve relative to the inner cable.

4. The fire extinguishing arrangement as claimed in claim 3, wherein the inner cable of the operating means extends through and between the first component and the second component, but the at least one sleeve is retained such that it does not extend between first component and second component.

5. The fire extinguishing arrangement as claimed in claim 3, wherein the at least one heat detector is arranged extending between the first component and the second component.

6. The fire extinguishing arrangement as claimed in claim 2, wherein the activator means has an out-of-use position and an activating position, the activator means being movable between the out-of-use position and the activating position.

7. The fire extinguishing arrangement as claimed in claim 6, wherein the trigger mechanism comprises a biasing means for biasing the activator means towards the activating position for activating the extinguisher.

8. The fire extinguishing arrangement as claimed in claim 7, wherein the trigger mechanism comprises a means for releasably retaining the activator means in the out-of-use position.

9. The fire extinguishing arrangement as claimed in claim 8, wherein the at least one heat detector is operably engaged with the means for releasably retaining the activator means in the out-of-use position and wherein on the detection of fire the at least one heat detector causes the means for releasably retaining the activator means in the out-of-use position to release the activator means.

10. The fire extinguishing arrangement as claimed in claim 9, wherein the means for releasably retaining the activator means in the out-of-use position comprises a retaining element for retaining the activator means in the out-of-use position and wherein the operating means is operably engaged with the retaining element.

11. The fire extinguishing arrangement as claimed in claim 10, wherein the retaining element comprises an aperture for receiving the inner cable of the operating means and wherein the at least one sleeve of the operating means is retained on one side of the retaining element whereas the inner cable extends through to the other side of the retaining element.

12. The fire extinguishing arrangement as claimed in claim 11, wherein the at least one urging means is operable to urge the at least one sleeve against the retaining element.

13. The fire extinguishing arrangement as claimed in claim 1, wherein the fire extinguishing arrangement can be retrofitted into an existing washing machine without requiring any substantial modification to the washing machine.

14. The fire extinguishing arrangement as claimed in claim 1, wherein the fire extinguishing arrangement is a standalone arrangement that does not require an extraneous source of extinguishant.

15. The fire extinguishing arrangement as claimed in claim 1, wherein the trigger mechanism is operable to activate the means for stopping the electrical supply.

16. The fire extinguishing arrangement as claimed in claim 1, wherein the fire extinguishing arrangement comprises a means for activating an alarm when the at least one heat detector detects a pre-set temperature wherein the trigger mechanism is operable to activate the means for activating an alarm.

17. The fire extinguishing arrangement as claimed in claim 1, comprising a means for detecting a temperature of the fire extinguisher outside of a safe operating temperature, wherein the means for detecting a temperature of the fire extinguisher outside of a safe operating temperature comprises an electrical cut-off means for cutting off the electrical supply when a predetermined temperature is reached.

Description

(1) The invention will now be described with reference to the accompanying drawings which shows by way of example only three embodiments of an apparatus in accordance with the invention.

(2) FIG. 1 is a schematic diagram of a fire extinguishing arrangement according to the invention;

(3) FIG. 2 is a side elevation view of a part of a fire extinguishing arrangement according to the invention;

(4) FIG. 3 is a rear elevation view the part of the fire extinguishing arrangement of FIG. 2;

(5) FIG. 4 is a plan view of the part of the fire extinguishing arrangement of FIG. 2;

(6) FIG. 5 is an expanded view of component parts of the fire extinguishing arrangement;

(7) FIG. 6 is a side elevation view of a heat detector and urging means according to the invention;

(8) FIG. 7 is a perspective view of a component part of the urging means in FIG. 6;

(9) FIG. 8 is a perspective view of another component part of the urging means in FIG. 6;

(10) FIG. 9 is a plan view of the component part in FIG. 8;

(11) FIG. 10 is an end view of the component part in FIG. 8; and

(12) FIG. 11 is a perspective view of the heat detector shown in FIG. 6;

(13) FIG. 12 is a perspective view of a further embodiment of a fire extinguishing arrangement according to the invention;

(14) FIG. 13(a) is a side view of the fire extinguishing arrangement of FIG. 12;

(15) FIG. 13(b) is a circuit symbol for an infra-red heat detector;

(16) FIG. 14 is a perspective view of a further embodiment of a fire extinguishing arrangement according to the invention;

(17) FIG. 15 is an expanded perspective view of an urging means according to the invention in position on an operating means;

(18) FIG. 16 is an additional view of the urging means of FIG. 15 without the operating means;

(19) FIG. 17 is a perspective view of an urging means with a fusible link as a heat detector, held in tension;

(20) FIG. 18 is a side view of an urging means with a frangible bulb as a heat detector, held in compression;

(21) FIG. 19 is a front view of a component of an urging means;

(22) FIG. 20 is side view of the urging means component of FIG. 19;

(23) FIG. 21 top view of the urging means component of FIG. 19;

(24) FIG. 22 is an expanded side view of the embodiment of FIG. 12.

(25) FIG. 23 is a further expanded view of FIG. 22.

(26) FIG. 24 is a component part of the fire extinguisher apparatus.

(27) FIG. 25 is the component part of FIG. 24 before forming into shape for use.

(28) FIG. 26 is an expanded view of a part of the embodiment of FIG. 12.

(29) FIG. 27 is a perspective view of a part of the embodiment of FIG. 12.

(30) FIG. 28 is a side view of a part of the embodiment of FIG. 12.

(31) In FIG. 1 there is shown a schematic representation of a fire extinguishing arrangement indicated generally by reference numeral 1. The arrangement 1 involves a fire extinguisher 2, which contains pressurized carbon dioxide although other suitable extinguishants could feasibly be used, and a trigger mechanism 3 operable to trigger the fire extinguisher 2 to release the extinguishant. The fire extinguishing arrangement 1 further involves six heat detectors 4a-f. The heat detectors 4a-f are placeable at locations distal to and remote from the fire extinguisher 2 or they may be placed beside the fire extinguisher 2 as required. Each heat detector 4a-f is formed as a fusible metal link 4a-f (see also FIGS. 5 and 10). Any number of heat detectors could be used with the arrangement. Each fusible link 4a-f can be arranged at a different location, for example in and around an electrical appliance, and each is capable of melting and operating the trigger mechanism 3. The fusible links 4a-f are pre-set at different melting temperatures such that heat detectors that trigger at higher temperatures can be disposed adjacent to areas of an appliance that are prone to heating during use. In this embodiment, fusible links 4a, 4b, 4e and 4f melt at 60? C. whereas links 4c and 4d melt at 110? C. These temperatures are adjustable by altering the fusible link or other heat detector as required. The fire extinguisher 2 and trigger mechanism 3 has main dimensions of 35 by 210 by 60 mm. By main dimensions we mean these dimensions exclude the size and shape of the operating means which extends from at or about the fire extinguisher 2 as discussed in detail below. Alternative sizes and shapes could be used provided the fire extinguishing arrangement can be integrated into a large domestic electrical appliance, and, in particular, provided that the fire extinguisher 2 can be placed in the free internal space around the inner workings of a large domestic appliance. While it would be preferable that the entire fire extinguishing arrangement 1 is located entirely within the boundary of the appliance after installment, there is often some free space between the rear of the appliance and the wall at which it sits against. This space could also be occupied by part of the fire extinguishing arrangement 1 if required. The entire fire extinguishing arrangement 1 can be set around the inner workings of a domestic clothes dryer, washing machine, refrigerator, freezer, fridge-freezer or dishwasher occupying the free internal space thereof, and it is not required to modify the appliance, for example, by applying any fittings or fixings to internal surfaces, making the arrangement 1 easy to install. Furthermore, it is not required to plumb the fire extinguishing arrangement 1 into a water source or other source of extinguishant.

(32) FIGS. 2 to 4 show the arrangement between the fire extinguisher 2 and the trigger mechanism 3. The fire extinguishing arrangement 1 has an arrangement 5 for stopping an electrical supply to the appliance in which the fire extinguishing arrangement 1 is to be integrated. The arrangement 5 is a microswitch which breaks an electrical circuit when the trigger mechanism 3 is triggered. The fire extinguishing arrangement 1 further has an arrangement for activating an alarm. In the embodiment in FIGS. 2 to 4, the arrangement 5 for stopping the electrical supply, and the arrangement for activating an alarm are both provided by a microswitch. The microswitch operates by breaking the undesired electrical circuit (i.e. the power-supply circuit to the appliance) in the event of a fire and simultaneously forming a circuit which sounds an audio or visual alarm, or alerts emergency services. The microswitch has three ports 6a, 6b, 6c for receiving electrical wiring and forming a circuit. Mains electricity can be wired into the arrangement 5 for stopping the electrical supply along with an electrical appliance to which the fire extinguishing arrangement 1 is to be incorporated. When the trigger mechanism 3 is operated the arrangement 5 for stopping the electrical supply breaks the circuit between the mains electricity and the electrical appliance. An alarm may also be wired into the microswitch which switches on the fire alarm system when a fire or excessive heat is detected, most preferably, by switching the electrical supply to the appliance from the appliance to the alarm system. Wireless solutions are also within the scope of the invention, where the detection of the trigger mechanism 3 activating could be determined by a sensor which wirelessly transmits a signal to turn off an appliance and/or activate an alarm, for example.

(33) The fire extinguishing arrangement 1 further has an arrangement for detecting a temperature of the fire extinguisher outside of a safe operating temperature. The arrangement in the embodiment on FIG. 1 is provided by a thermal fuse 75 attached to or set beside the fire extinguisher 2, and a wire 76 connecting the arrangement 5 for stopping the electrical supply to the thermal fuse 75. The mains electricity can be wired into the thermal fuse 75 which in turn provides an electrical supply to the arrangement 5 for stopping the electrical supply. The electrical supply of an appliance, such as a washing machine, in which the fire extinguishing arrangement 1 is fitted, can be wired into the arrangement 5 for stopping the electrical supply and the thermal fuse 75. If the temperature around the thermal fuse exceeds 50? C. the thermal fuse will cut the circuit thereby cutting power to the appliance. This can occur during the outbreak of a fire or in the event the electrical appliance is overheating. This ensures that the temperature around the extinguisher 2 does not rise above safe temperatures, at which the extinguisher could potentially rupture or explode. Alternative electrical cut-off arrangements such as a thermostat could be used, but a thermal fuse 75 offers a simple and cost-effective solution for ensuring safety.

(34) The trigger mechanism 3 has a fire extinguisher support component formed as a metal plate 7 with an aperture 8 therethrough and an M16 nut 9 arranged at one end of the aperture 8, welded to the metal plate 7, for receiving and holding the fire extinguisher 2. Alternative devices to an M16 nut may be used provided they retain the fire extinguisher 2 at the fire extinguisher support component. The M16 nut 9 enables the fire extinguisher 2 to be screwed on to the fire extinguisher support component 7, but other means of attachment could be used, or the fire extinguisher could be integrally formed with the fire extinguisher support component 7. The aperture 8 provides access through the fire extinguisher support component 7 to the fire extinguisher 2 when the fire extinguisher 2 is screwed into position on the M16 nut 9. The trigger mechanism 3 further has an activator arrangement 10 formed as a spike 11 appended to a plate 12. The fire extinguisher support component 7 and the activator plate 12 are connected at one end via a hinge 13. The hinge 13 is formed from a flexible sheet of metal that is spot welded to the fire extinguisher support component 7 and the activator plate 12. The spike 11 is aligned with the aperture 8 in the fire extinguisher support component 7 such that when the activator plate 12 and the fire extinguisher support component 7 are laid together, the spike 11 extends through the aperture 8 such that it can engage with the fire extinguisher 2.

(35) The trigger mechanism 3 further involves a biasing means, provided by a coil spring 20, operably engaged with the activator plate 12 for biasing the activator plate 12 against the fire extinguisher support component 7. The spring 20 extends from a base 40 of a biasing arrangement support 41, which in turn extends from the fire extinguisher support component 7. The spring 20 extends through an aperture 42 in the fire extinguisher support component 7 and through an aperture 43 in the activator plate 12. It is retained against the activator plate 12 by hooking it through the aperture 43. The spring 20 can move freely through the aperture 42 of the fire extinguisher support component 7.

(36) The trigger mechanism 3 further involves an arrangement 25 for overcoming the biasing force of the spring 20 and for retaining the activator arrangement 10 in an out-of-use position. A flange 14 extends from the hinge 13 at the activator plate 12 end of the hinge 13. The arrangement 25 for retaining the activator arrangement 10 in an out-of-use position has an elongate operating means 15, provided by a Bowden cable. The operating means 15 has an inner cable 15a and an outer sleeve 15b. In FIG. 1, the outer sleeve 15b is arranged as seven separate sleeves. The inner cable 15a and the sleeve 15b are coaxial and the sleeve 15b can move relative to the inner cable 15a. The flange 14 which extends from the hinge 13 has an aperture 45 and the inner cable 15a extends therethrough. The inner cable 15a further extends along the activator plate 12 such that, in use, the spike 11 is located between the inner cable 15a and the fire extinguisher 2. The inner cable 15a is anchored at one end to the flange 14 via a flange anchor 16 which is sized greater than the width of the aperture in the flange 14. The opposing end of the inner cable 15a could be clamped to a surface, an urging device (as discussed later), or may simply be a free end of the operating means 15.

(37) The arrangement 25 for retaining the activator arrangement 10 in an out-of-use position comprises a retaining element 26 for retaining the activator plate 12 at a distance to the fire extinguisher support component 7. The retaining element 26 is elongate and is connected at one end to fire extinguisher support component 7. At the end of the retaining element 26 opposing the portion connected to the fire extinguisher metal plate 7 is a retaining element aperture 46. The inner cable 15a extends through the retaining element aperture 46 such that the inner cable 15a extends from the flange 14 and through the retaining element aperture 46. The retaining element 26 is located between the sleeve 15b and the flange 14 such that the sleeve 15b can urge the retaining element 26 towards the flange 14. The retaining element 26 further has a recess 47 for receiving and retaining the end portion of the activator plate 12. The retaining element 26 is formed from malleable metal such that it can displaced by movement of the activator plate 12 when, for example, the sleeve 15b is no longer being urged towards the retaining element 26. This would release the activator plate 12 and allow the spring 20 to draw the activator plate 12 towards the fire extinguisher support component 7. This thereby rapidly pulls the spike 11 towards the fire extinguisher 2. When the activator plate 12 is set in the recess 47 a roughly triangular shape is formed between the inner cable 15a, the retaining element 26 and the fire extinguisher support component 7.

(38) The fire extinguishing arrangement 1 further has a support bracket 70 which is connected to, and extends orthogonally from, the fire extinguisher support component 7. The support bracket 70 extends alongside the activator plate 12. The arrangement 5 for stopping the electrical supply is attached to the support bracket 70 in a location overhanging the activator plate 12. When the fire extinguishing arrangement 1 is primed in use, the activator plate 12 is operably engaged with a switch 71 of the arrangement 5 for stopping the electrical supply and can operate the switch 71 and therefore the arrangement 5 for stopping the electrical supply by being moved towards the fire extinguisher metal plate 12. The support bracket 70 may further be used to fix the trigger mechanism 3 to a surface such as the interior side surface of a washing machine.

(39) The fire extinguishing arrangement 1 has a series of six urging devices 50a, 50b, 50c, 50d, 50e, 50f for urging the sleeves 15b along the inner cable 15a (see FIGS. 1, 6 and 7). Any number of urging devices could be used in conjunction with the operating means 15. Each urging device 50a, 50b, 50c, 50d, 50e, 50f has a first component 51 and a second component 52. The first component 51 and the second component 52 are each formed from a metal sheet with two reinforcing folds 60a, 60b, along the peripheral edges forming an elongate, U-shaped channel. Each component 51, 52 further has an aperture 61a, 61b at each end wherein one aperture 61a is formed for receiving the inner cable 15a and the other aperture 61b is formed for attaching a fusible link 4a or other heat detector. The inner cable 15a of the operating means 15 extends through the first component 51 and the second component 52 but the sleeve 15b is retained on one side of the first component 51 and the second component 52. The first component 51 is retained distal to the second component 52 by a separator 53 formed as an elongate metal plate with two seats 54a, 54b at opposing ends shaped to accommodate the U-shaped channel form of the first component 51 and the second component 52 respectively.

(40) The separator 53 is located between the two apertures of the first component 51 at one end and between the two apertures of the second component 52 at the opposing end. Moving the ends of the first component 51 and the second component 52 respectively that are distal to the operating means 15 closer together causes the components 51, 52 to pivot about the separator and to increase the distance between the ends of the first component 51 and the second component 52 at the operating means 15. This forces the separate sleeves 15b apart and can urge the sleeve 15b against the retaining element 26. The fusible links 4a, 4b, 4c, 4d, 4e, 4f are formed extending between the end portion of the first component 51 and the end portion of the second component 52 respectively. The urging force can be adjusted by adjusting the length of the fusible links 4a, 4b, 4c, 4d, 4e, 4f. If the fusible link 4a breaks, the urging force of the sleeve 15b released.

(41) In use, the fire extinguishing arrangement 1 is fitted within and/or around an appliance such as a clothes dryer, dishwasher or washing machine with the purpose of extinguishing a fire initiated by a fault in the appliance. The trigger mechanism 3 can be fixed to the appliance either via the support bracket 70 or otherwise or can simply be set into place within the appliance without securement. The fire extinguishing arrangement 1 is prepared by sliding a first sleeve 15b along the inner cable 15a and then sliding a first urging device 50a along until the first sleeve 15b abuts the retaining element 26. Additional sleeves and urging devices are then added. The sleeve 15b length can be adjusted to adjust the location and/or number of urging devices present within the fire extinguishing arrangement 1 along the operating means 15.

(42) The activator plate 12 is moved in an arch, pivoting about the hinge 13, away from the fire extinguisher support component 7, and the retaining element 26 is bent towards the activator plate 12 until the end portion of the activator plate 12 is seated within the recess 47 of the retaining element 26. The urging devices 50a, 50b, 50c, 50d, 50e, 50f are adjusted by moving them along the inner cable 15a to urge the sleeve 15b towards the retaining element 26 thereby holding the activator plate 12 within the recess 47. The end of the inner cable 15a distal to the trigger mechanism 3 is retained at or about the urging device furthest from the trigger mechanism 3 by a stopper 17. Alternatively, the terminal end could be clamped to a surface or structure via a clamp, the free end of the operating means 15 could simply have a cap or other structure fixed to the inner cable 15a to prevent the terminal outer sleeve 15b from sliding off the free terminal end of the inner cable 15a.

(43) The spring 20 is then attached to the activator plate 12 by hooking it through the aperture 43, effectively priming the fire extinguishing arrangement. In this configuration the spring 20 will be stretched and will be urging the spike 11 towards the fire extinguisher 2 but the retaining element 26 and the urging force of the sleeve 15b retains the activator arrangement 10 in the out-of-use position. Either before or after priming the arrangement, the appliance is electrically wired into the arrangement 5 for stopping the electrical supply and a mains wire is also wired into the arrangement 5 such that a circuit is formed between the mains wire and the appliance. Additionally, a wire is ran from the microswitch of the arrangement 5 for stopping the electrical supply to an alarm system forming a circuit between the alarm system and the mains electricity. The microswitch of the arrangement 5 for stopping the electrical supply is arranged such that the appliance is switched on whilst the alarm system is off and operation of the switch 71 reverses the configuration. The activator plate 12 is arranged in operable engagement with the switch 71 of the arrangement 5 for stopping the electrical supply. The appliance can then be closed and sealed up if necessary, thereby concealing the fire extinguishing arrangement 1.

(44) The spring 20, via the retaining element 26, is constantly forcing the sleeve 15b along the inner cable 15a away from the retaining element 26, but movement along the cable 15a is prevented by the urging devices 50a, 50b, 50c, 50d, 50e, 50f. After the fire extinguishing arrangement 1 has been set into or round an appliance, the heat detectors 4a, 4b, 4c, 4d, 4e, 4f and urging devices 50a, 50b, 50c, 50d, 50e, 50f can be arranged in different locations throughout the appliance. The fire extinguishing arrangement 1 is relatively small and the operating means 15 is thin and easily moveable, so the entire arrangement 1 can be set inside a typical domestic clothes dryer, dishwasher or washing machine, between the exterior of the drum and the interior walls of the casing. An installer can simply open the casing of the appliance, set the fire extinguishing arrangement 1 inside the appliance, and close the casing.

(45) If a fault occurs in the appliance which leads to a fire, at least one of the heat detectors (fusible links 4a, 4b, 4c, 4d, 4e, 4f) incorporated into the urging devices will partially melt or rupture. This causes the urging force of the urging device within which the melted fusible link is located to be released. The urging device can no longer retain the sleeve 15b located at either side of the urging device along the inner cable 15a apart and the sleeve 15b is freed to move along a portion of the inner cable 15a. The spring 20 overcomes the retaining element 26 to pull the activator plate 12 out of the recess 47 towards the fire extinguisher support component 7 and push the sleeve 15b along the inner cable 15a away from the retaining element 26. The activator plate 12 and the fire extinguisher support component 7 snap together. The spike 10 passes through the aperture 8 of the fire extinguisher support component 7 and pierces the fire extinguisher 2 thereby releasing the extinguishant. Movement of the activator plate 12 towards the fire extinguisher support component 7 pulls the switch 71 of the arrangement 5 for stopping the electrical supply, breaking the circuit to the appliance and switching on the circuit to the alarm thereby operating the alarm. The spring 20, via the retaining element 26, is operable to push the sleeve 15b and any number of the urging devices 50a, 50b, 50c, 50d, 50e, 50f along the inner cable 15a in the event of one of the fusible links 4a, 4b, 4c, 4d, 4e, 4f melting.

(46) FIGS. 12 and 13 show a further embodiment of a fire extinguishing apparatus indicated generally by reference numeral 101. The fire extinguishing apparatus 101 has an adjuster 180 which is operably connected to the biasing means 120. The biasing means 120, which is a coil spring in this embodiment, terminates in a hook 120a that engages with a through-bore on the adjuster 180. The adjuster 180 has a threaded bolt 180a that extends through an aperture 181 in the base 140 of the biasing arrangement support 141. A nut 181 is threaded onto the threaded bolt 108a on the opposing side of the base 140 to that of the biasing means 120. Hooking the biasing means 120 onto the adjuster 180 causes the threaded bolt 180a to be pulled in the direction of the biasing means 120 but it is retained at the base 140 by the presence of the nut 181. Moving the nut 181 along the threaded bolt 180a thereby alters the amount to the threaded bolt 180a that extends towards the biasing means 120 from the base 140 and there in turn alters the tension that the biasing means 120 applies to the activator plate 112.

(47) FIG. 14 is a perspective view of a further embodiment of a fire extinguishing apparatus indicated generally by reference numeral 201. In this embodiment, the trigger mechanism and fire extinguisher are located within an enclosure 285. The enclosure 285 has an aperture 286 for accommodating the operating means 215, and a vent 287 to allow the extinguishant to escape. The enclosure 286 could be fitted with a bracket, adhesive or other means (not shown) for attaching the enclosure 286 to a surface, such as an interior surface of a large domestic electrical appliances. The arrangement for activating an alarm, the arrangement for stopping the electrical supply and/or the electrical cut-off arrangement are each wired to a surface of the enclosure 286. In the embodiment shown, the wiring of these arrangements is accessible via electrical ports 288 on the surface of the enclosure 286.

(48) FIGS. 15 to 18 show views of an embodiment of an urging device indicated by reference numeral 150. In this embodiment, the first component 151 is in direct pivotal engagement with the second component 152. The separator 153 is integrally formed with the first component 151 and second component 152. The separator 152 is provided by two triangular flanges 153a, 153b, that each extend from respective faces of the first component 151 and second component 152. In use, the flange 153a of the first component 151 extends towards and engages with the second component 152, and the flange 153b of the second component 152 extends towards and engages with the first component 151. The face 151a of the first component 151, and the face 152a of the second component 152 each have an aperture 155a, 155b positioned to receive the flange 153a, 153b of the other component 151, 152. Each flange 153a, 153b has a widened portion 156a, 156b at its tip which prevents the flange 153a, 153b from easily being removed from the aperture 155a, 155b, thereby locking the first component 151 to the second component 152 and in pivotal engagement therewith.

(49) In FIGS. 15, 16 and 18, the heat detector 157a is a frangible bulb. The heat detector 157a is located extending between the first component 151 and the second component 152, in particular, extending between an aperture in the face 151a of the first component 151 to a corresponding aperture in the face 152a of the second component 152. The operating means 115 is arranged extending between the separator 153 and the heat detector 157a. In this embodiment, where the sleeve 115b is urged towards the first component 151, the first component 151 pivots about the separator 153 towards the second component 153 and consequently applies compression to the heat detector 157a. The compressive force is released when the heat detector 157a detects heat and bursts and the first and second components 151, 152 swing together about the pivoting separator 153.

(50) In FIG. 17, the heat detector 157b is a fusible link that is arranged extending between an aperture in the face 151a of the first component 151 to a corresponding aperture in the face 152a of the second component 152. The link can be fixed to the apertures in the faces 151a, 151b of the first and second component respectively by screw or bolt or other means, and they each extend underneath the separator 153, being linked at a location between the faces 151a, 152a of the first 151 and second 152 components. In this arrangement, the separator 153 is between the heat detector 157b and the operating means 115. In this embodiment, where the sleeve 115b is urged towards the first component 151, the first component 151 pivots about the separator 153 towards the second component 152 and consequently applies a tension to the heat detector 157b. The tension is released when the heat detector 157b separates, for example because of heat, and the first and second components 151, 152 swing together about the pivoting separator 153. The outer sleeve 115b can then move relative to the inner cable 115a and the trigger mechanism is triggered, causing the fire extinguisher 102 to release the extinguishant. The same urging device 150 can be used in either of the described arrangements and has apertures 158a, 158b, 158c, 158d located at either end of the faces 151a, 152a of the first and second components 151, 152 to receive a heat detector in either a compressive force arrangement or a tension force arrangement, depending on the placement of the heat detector relative to the separator 153 and the operating means 115.

(51) FIGS. 24 and 25 show a component part 190 of the trigger mechanism 103. The part 190 forms the activator plate 112 and is further shaped to receive and support the hinge 113 at one end 191, and the retaining arrangement 126 at the other end 192. FIG. 25 shows the component part 190 before it is folded into its final shape, whereas FIG. 24 shows the final form of the component part 190. The two end portions of the flat piece are bent at 90?, and then the sides of the bent end portions are folded inwards to produce reinforcing flanges 193 for strength. The hinge 113 can then be fit on to one end 191, and the retaining arrangement 126 on the opposing end 192.

(52) FIGS. 27 and 28 show yet a further component part 195 of the fire extinguishing apparatus 101. Component 195 forms the fire extinguishing support component 107, the biasing arrangement support 140, and the biasing arrangement support base 141. It is also shaped to receive and support part of the hinge 113 and the retaining arrangement 126. The component 195 is formed from a single piece of folded metal. A flat piece of metal is formed initially and then the biasing arrangement support base 141 is formed by a 90? bend, the sides of the base also being folded for reinforcing purposes. The fire extinguishing support component 107 is formed by bending a portion of the component 195 at an opposing end to the biasing arrangement support base 141. The ends of the fire extinguishing support component 107 are folded downwards towards the biasing arrangement support base 141. One end 196 receives and supports part of the hinge 113, and the opposing end 197 receives and supports the retaining arrangement 126. The component part 190 and component part 195 are fitted together, along with the hinge 113 and retaining arrangement 128 to form a large part of the structure of the trigger mechanism 103. A fire extinguisher 102 is screwed onto the fire extinguishing support component 107 and the biasing means 120 placed into position, the operating means 115 is also placed into position at the fire extinguishing support component 107.

(53) The fire extinguishing arrangement could be modified by using an electrically-powered heat detecting means, such as an infra-red sensor 350 (see FIG. 13(b)) which transfers a signal to the trigger mechanism, either through wired or wireless means, to trigger the fire extinguishing arrangement. The trigger mechanism could be arranged with a solenoid actuator (not shown) that, upon receiving a signal from the infra-red sensor or other electrically-powered heat detector, moves the position of the retaining element such that the biasing means can move the activator towards the fire extinguisher.

(54) In the preceding discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of the values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of the parameter, lying between the more preferred and the less preferred of the alternatives, is itself preferred to the less preferred value and also to each value lying between the less preferred value and the intermediate value.

(55) The features disclosed in the foregoing description or the following drawings, expressed in their specific forms or in terms of a means for performing a disclosed function, or a method or a process of 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 as defined in the appended claims.