GB2163345A - Spherical fire extinguisher - Google Patents

Abstract

A fire extinguisher comprising a hollow spherical body, a fixing plate fixed to the exterior surface of said body, an ejection nozzle communicating with said body removably engaged into a through-hole in the body opposite to said fixing plate, and a cylinder for use in ejecting fire extinguishing agent inserted into a second through-hole in the body. The extinguisher can eject fire extinguishing agent at a constant pressure throughout the duration of operation. <IMAGE>

Description

SPECIFICATION Spherical fire extinguisher The present invention relates to a fire extinguisher.

More particularly it relates to a spherical fire extinguisher.

Conventional cylindrical types of fire extinguishers, whilst being able to efficiently eject a fire extinguishing agent at a constant pressure during the initial fire extinguishing operation, display the disadvantage that the pressure of part of the compressed gas is concentrated at the nozzle over a period ranging from the intermediate to the later stage ofthe operation.

Therefore, as the extinguishing agent is ejected, a pressure reduction occurs leading to incomplete discharge ofthefire extinguishing agent. Therefore, incomplete extinguishing of a fire might occur.

The conventional cylindrical shape of a fire extinguisher is difficult to install on the ceiling or side of a room and is, furthermore, not the most aesthetically appealing shape.

It can be therefore seen thatthere is a need to develop a fire extinguisher not having the disadvantages discussed above. It was desired to produce an aesthetically appealing extinguisherwhich gave a constant discharge of extinguishing agent at an ejection angle capable of applying sufficient power of agentto extinguish a fire. It was also desired to produce an extinguisher which could be operated both automatically and manually.

According to the present invention there is provided a fire extinguishercomprising a hollow spherical body, a fixing plate fixed to the exterior surface of said body, an ejection nozzle communicating with said body removably engaged into a through-hole in the body opposite to said fixing plate, and a cylinderfor use in ejecting fire extinguishing agent inserted into a second through-hole in the body.

One embodiment of the present invention will now be described with reference to the accompanying drawings, in which; Figure 1 shows a half section view of a spherical fire extinguisher according to the present invention.

Figure 2 is a bottom view of the extinguisher.

Figure 3 is a front elevational view of a nozzle fitted to the extinguisher.

Figure 4 is a longitudinal section through Figure 3.

Figure 5 is a top plan view of a swirl plate.

Figure 6 is a longitudinal section through Figure 5.

Figure 7 shows the ejection angle of extinguishing agent ejected from an ejection hole in the nozzle.

Figure 8 shows the ejection scope or range of extinguishing agent ejected from the ejection hole shown in Figure 7.

Figure 9 is a longitudinal section of a sensor installed in the extinguisher.

The fire extinguisher, a, in Figure 1 comprises a spherical body 1 made of metal plate, usually of stainless steel. A planarfixing plate3 is fixed to a desired point on the outer surface 4 of the spherical body 1, normally at a rightangleto the centre line 2. In orderto fix the plate 3, an auxiliary narrow, columnlike fixing part 5 may be directly fixed at a right angle to the centre line 2 and the fixing plate 3 may be fixed through the auxiliaryfixing part 5.

A fire extinguishing agent ejection nozzle 6 is removably fitted to a through-hole opposite the pintto which the fixing plate 3 is fixed. The nozzle 6 is affixed by a threaded part 8 to the through-hole 7 formed in the spherical body 1. The nozzle 6 has a body 10 of circular shape. Upon the surface ofthe body 10 and at the centre thereof is a small circular part 12 which is parallel with a flange 11. this part 12 surrounds an ejection hole 13 at the centre thereof. Four small circular parts 12' having similar shape to each other areformed between the ejection hole 13 and the flange 11, the parts 12' being arranged around the ejection hole 13 in a radial direction from the outer surface of the small circular part 12 toward the flange 11.Each ofthe ejection holes 13' is of a similar shape and is formed at the centre of each ofthe small circular parts 12'. To the rear surfaces ofthe small circular parts 12 and 12' are attached swirl plates 14 integrally fixed to face in different directions and having a small hole 15 therein and a plurality of eddy flow generating vanes 16. The body 10 ofthe nozzle 6 is fixed to the spherical body 1 by a fixing part 18 having a through-hole 19 at the centre thereof. Afilm packing 17 closesthethrough-hole 19.

A sensor 20 for automatic fire extinguishing is fitted to the outer surface of the spherical body 1 between the fixing plate 3 and the nozzle 6 via a through-hole 21. The fitting point of the sensor 20 is not limited to that shown in the drawings. The sensor 20 comprises a cylinder 22 for ejecting a fire extinguishing agent filled with non-combustiblefluid at high pressure.

This cylinder 22 is fixed to a column 24 which itself is fitted and fixed to the extremity end of a sleeve 23 by meansofascrew25atthe lower partthereof. A plunger 27 is located above a striking needle 26 which may breakthrough a sealing plate ofthe cylinder 22 (not shown). The needle 26 is slidablyfitted in the column 24 and thereby a non-combustible fluid ejection passage 28 for guiding the injecting noncombustible fluid into the spherical body 1 may be formed.The cylinder22 and the sleeve 23 are covered by a sealing shield 29 for chemically protecting the fire extinguishing agent. The base end of the sealing shield 29 is held by a fitting piece 30 integrally arranged with the spherical body 1 and an end plate 31 with which the sleeve 23 is th readably engaged.

Within a frame plate 33 which is fixed to the fitting piece 30 along with the end plate 31 by a lock nut 32 threadably engaged with the fitting piece 30 is arranged a plate receiving pin 34. A striking needle operating plate 35 of which one end is engaged with the plate receiving pin 34 passes through the end plate 31 and the other end is guided into the sleeve 23. To the striking needle operating plate 35 is abutted a spring holder 36 and the striking needle operating plate 35 is always kept compressed against the plunger27 under an extending and retracting force of a compression coil spring 37 installed between the spring holder 36 and the end plate 31. In afuse acceptor38 opposite the plate receiving pin34 (one end ofthe striking needle operating plate 35 being held thereagainst) is inserted a fuse 39 of low melting point (about 70 degrees C, for example).The fuse 39 is retained in the fuse acceptor 38 by a holding block 41 supported in the frame plate 33 by an adjusting screw 40. The screw 40 is within a screw acceptor 43.

Although one end ofthe striking needle operating plate 35 is pushed againstthefuse acceptor 38 under a combined action of the extending and retracting force ofthe compression coil spring 37 and the plate receiving pin 34and isaptto be removed from the plate receiving pin 34, one end of the striking needle operating plate 35 is kept pushed againstthe plate receiving pin 34 bythefuse 39 and the holding block 41.

A protection cover 42 also acts as a thermal conducting plate which is integral with the fuse acceptor 38. A connecter lever 44 is connected to the screw acceptor 43 and projects out ofthe upper surfaceofthe protection cover 42. A hand and finger hook 45 is positioned atthe upper surface ofthe protection cover 42, one end ofthe hook being pivotallyfitted to the connector 44 and the other end being removably fitted to a hook 46 fixed to the upper surfaceofthe protection cover 42.

The mode of action of the fire extinguisher according to the above-described embodiment will now be described In automatic use, as the temperature ofthe surrounding atmosphere is increased, the fuse 39 melts. As the molten fuse starts to flow out of a clearance between the holding block 41 andthefuse acceptor 38, the extending and retracting force of the compression coil spring 37 overcomes the force of the holding block, such that one end ofthe striking needle operating plate 35 is removed from the plate receiving pin 34. The striking needle operating plate 35 strikes againsttheplunger27, and the striking needle 26 breaks throug h the sealing plate of the cylinder 22.

Non-combustible fluid overflows the non-combusti ble fluid ejection passage 28, breaks the sealing shield 29 under its pressure, and the fluid blows out into the fire extinguisher agent contained in the sphere body 1.

The fire extinguishing agent is then ejected from each ofthe ejection holes 13, 13' constituting the nozzle 6.

In manual use, the hosk 45 is pulled by the operator's fingers. The connector lever 44 connected to the hook 45 to pull the adjusting screw 40 and thus the holding block 41 and the fuse 39 are disengageed from the fuse receiver 38. As the fuse 39 is disengaged, the extending and retracting force ofthe compression coil spring 37 is simultaneously overcome causing one end ofthe striking needle operating plate 35 to be disengagedfromthe plate receiving pin 34. The striking needle operating plate 35 strikes againstthe plunger27 and the striking needle 26 breaks through the sealing plate ofthe cylinder 22.Non-combustible fluid overflows the non-combustiblefluid injection passage 28, breaking the sealing shield 29 by its pressure and the fluid blows out into the fire extinguisher agent contained in the sphere body 1. The fire extinguishing agent is then ejected from each ofthe ejection holes 13,13' constituting the nozzle 6.

The spherical fire extinguisher ofthe present invention (to which the injection nozzle 6 and the sensor20forautomaticfireextinguisherarefitted) may be fixed to a ceiling wall surface in a room by nails orscrews, for example, through the fixing plate 3.The fire extinguisher ofthe present invention may also be hooked on to a side wall or may be placed on the upper surface offurniture, perhaps as an ornamental item.

In the present invention, unlike conventional types offire extinguishers, a hollow spherical body 1 is used in place of a cylinder. Thereby, pressure of noncombustible fluid overflown from the cylinder 22 is applied to the liquid surface (projected area) ofthe fire extinguishing agent, and the pressure is concentrical- ly applied to the ejection surface of ejection holes 13, 13'. However, after ejection starts, due to a low area of liquid surface of fire extinguisher agent, the pressure is temporarily reduced and in turn the pressurizing area (projected area) is gradually expanded, so that the ejection pressure is not reduced. Therefore, the fire extinguishing agent is fully ejected.

The ejection pressure as the extinguishing agent is ejected from the ejection holes 13,13 in the nozzle 6 can be expressed asfollows; Ejection pressure = Projected area of sphere body Nozzle ejection projected area x (pressure in a gas cylinder) The present invention as described above may be compared to conventional types offire extinguisher.

As stated,the body is spherical ratherthan cylindric al, which means that as the pressure of non combustible fluid ejected from the cylinder is applied to the liquid surface (projected area) ofthefire extinguisher agent, a pressurizing force atthe liquid surface passing through the centre shows the max imum value. Even when the pressure is gradually decreased from the centre toward the nozzle, the liquid surface of the fire extinguisher agent decreases not rapidly, but gradually.

The fire extinguisher according to the present invention has advantages that an excessive reduction in pressure should not occur and that during a pressurizing opeerationfortheliquidsurface,thefire extinguisher agentflows smoothly along the inner surface of the sphere body.

Thefire extinguisheraccording tothe present invention, iseasierthan conventional types of fire extinguishers to affixto the ceiling orwall surface of a room, and does not detractfrom the overall appear ance ofthe room.

Claims (11)

1. Afire extinguisher comprising a hollowspher ical body, a fixing plate fixed to the exterior surface of said body, an ejection nozzle communicating with said body removably engaged into a through-hole in the body opposite to said fixing plate, and a cylinder for use in ejecting fire extinguishing agent inserted into a second through-hole in the body.

2. Afire extinguisheras claimed in Claim 1 wherein the body is constructed from stainless steel.

3. Afire extinguisher as claimed in either Claim 1 or Claim 2wherein the fixing plate is fixed to the exterior surface ofthe body at a right angle in respect to a centre line thereof.

4. Afire extinguisher as claimed in any one of Claims 1 to 3 wherein the ejection nozzle comprises a plurality of ejection outlets.

5. Afire extinguisher as claimed in any one of Claims 1 to 4which further comprises a sensorfor use in automatic detection of a fire and operation ofthe extinguisher.

6. Afire extinguisher as claimed in Claim 5 wherein the sensor operates by means of a low melting point fuse.

7. Afire extinguisher as claimed in Claim 5 or Claim 6 wherein the sensor is adpated for manual use.

8. Afire extinguisheras claimed in Claim 1 and substantially as hereinbefore described.

9. Afire extinguisher as claimed in Claim 1 and substantially as herebefore described with reference to and as illustrated in Figures 1 to 6 of the accompanying drawings.

10. A method ofextinguishing a fire, which method comprises the use of a fire extinguisher as claimed in any one of Claims 1 to 9, said use being either automatic or manual.

11. A method as claimed in Claim 10 and substantially as herebefore described.