IL94367A - Fire extinguishing method and apparatus - Google Patents

Description

FIRE EXTINGUISHER METHOD AND APPARATUS FIRE EXTINGUISHING METHOD AND APPARATUS The present application is for a Patent-of-Addition to Patent No.92951 filed January 3, 1990, and relates to improvements in or modifications to the method and apparatus for extinguishing a fire described in that patent application.

Patent . No.92951 discloses a method for extinguishing a fire characterized in applying an intense electromagnetic field to the base of the fire sufficient to extinguish the fire. The fire may be detected by a fire detector, and the intense electromagnetic field may be applied to the base of the fire automatically in response to such detection. Alternatively, after a fire has been detected in any manner, the application of the intense electromagnetic field to the base of the fire may be manually initiated.

According to another aspect of the invention described in Patent No.92951, there is provided apparatus for extinguishing a fire comprising: a source of high voltage; a pair of electrodes electrically connected to the high voltage source and defining an airgap between them; means for locating the airgap adjacent the base of the fire; and an actuator for actuating the high voltage source to produce an intense electromagnetic field across the airgap sufficient, when located adjacent the base of the fire, to extinguish the fire. That application described a number of embodiments of such apparatus.

The present application describes further embodiments of apparatus for extinguishing a fire in accordance with the method of Patent No.92951.

According to one embodiment described in the present application, the high voltage source, the pair of electrodes, and the actuator, are all carried by a portable manually-actuated unit.

According to further features in this embodiment as described in the present application, the portable manually-actuated unit includes a handle and the actuator adjacent one end, the airgap defined by the electrodes adjacent the opposite end, and the high voltage source between the handle and the airgap. More particularly, the handle includes a first handgrip at the one end, and a second handgrip spaced from the first handgrip towards the opposite end. In the described preferred embodiment, the portable manually-actuated unit comprises an elongated member carrying the first and second handgrips adjacent one end thereof, the two electrodes defining the airgap adjacent the opposite end thereof, and the high voltage source at an intermediate location therebetween.

Another embodiment of the invention is described in the present application, wherein the airgap is located adjacent the top of a container for an inflammable liquid.

According to further features in the latter embodiment of the invention as described in the present application, the container is of metal and serves as one electrode of the airgap, and the other electrode of the airgap is disposed in air above the liqud level in the container and has a tip within the periphery of the container. More particularly, the second electrode is mounted on an insulating member externally of the container and includes a conductor overlying the top of the container and extending inwardly thereof at an oblique angle to the longitudinal axis of the container .

The latter embodiment of the invention may also be used with a plurality of containers, in which case the apparatus would include a plurality of the second electrodes each defining an airgap between it and the respective container, the airgaps being connected in parallel to the high voltage source.

The foregoing embodiments of the invention as described in the present application will be better understood by reference to the accompanying drawings, wherein: Fig. 1 illustrates one form of the apparatus embodied in a portable manually-actuated unit constructed in accordance with the invention; Fig. 2 illustrates another form of apparatus constructed in accordance with the invention for extinguishing a fire that may occur in a container containing an inflammable liquid; and Fig. 3 illustrates the apparatus of Fig. 2 but embodied in a system to protect a plurality of containers containing inflammable liquids.

Fig. 1 illustrates a portable manually-actuated unit for use to extinguish a fire. Such a unit includes an elongated member, generally designated 200, carrying a first handgrip 202 at one end, and a second handgrip 204 adjacent to but inwardly of handgrip 202. The elongated member carries a pair of electrodes 206, 208 defining an airgap 210 at the opposite end, and a source of high voltage 212 at an intermediate location between handgrips 202, 204 and airgap 210.

The two handgrips 202, 204 thus constitute a handle adjacent one end of the elongated member 200 facilitating manually carrying the portable unit while the two handgrips are grasped by the two hands of the user, enabling the user to direct the airgap 210 at the base of the fire to be extinguished. Handgrip 204 includes an actuator button 214 which is manually depressed by the user in order to initiate the application of the high voltage from the high voltage source 212 across the airgap 210. The high voltage source 212 further includes an indicator lamp 216 which is energized whenever the high voltage source 212 is actuated by actuator button 214.

As one example, elongated member 200 may be an aluminum pipe of 2 cm diameter and of 110 cm length; the high voltage source 212 may be a high voltage generator producing about 25 kV and supplied by rechargeable batteries (e.g., nickel-cadmium) included within the high voltage source; and electrode 206 may be a steel rod of 5 mm diameter and of 40 cm length, coaxial with aluminum pipe 200 and insulated therefrom by a ceramic insulator 218. Electrode 206 may be connected to the plus-terminal of the high voltage source 212; and electrode 208 may be an electrically-conductive rod of nickel-chromium, 1 mm diameter, connected to the negative-terminal of the high voltage source 212. Electrode 208 may be insulated by a ceramic sleeve 220 extending for the complete length of the electrically-conductive rod but terminating short of its tip so that the bare tip of rod 208 defines the airgap 210 with the bare tip of the steel rod 206. As shown in Fig. 1, the steel rod 206 extends substantially coaxially with the aluminum tube 200, whereas rod 208 extends from the high voltage source 212 laterally thereof but is bent in the general axial direction to terminate adjacent the end of rod 206 to define the airgap 210.

Fig. 2 illustrates apparatus for use in extinguishing a fire which may occur in an inflammable liquid in a container 300. In this case, the container 300 is of metal and serves as one of the electrodes of the airgap across which the high voltage is applied to extinguish the flame.

In the apparatus illustrated in Fig. 2, the second electrode of the airgap is shown at 302 and is mounted on a stand 304 supported on a base 306. Stand 304 is vertically adjustable with respect to base 306, and electrode 302 is horizontally adjustable with respect to stand 304. This mounting arrangement thus permits electrode 302 to be adjusted both vertically and horizontally.

Electrode 302 includes a section 302a insulated by a layer 310 of suitable insulation material, and a bare section 302b at its outer tip overlying the upper end of the metal container 300. The bare tip 302b of electrode 302 is inclined downwardly so as to terminate over, but within the periphery of, the container 300 such that the airgap defined by the bare electrode tip 302b, and the upper edge of metal container 300, would be in the vicinity of the base of any fire that may occur within the container.

The high voltage power supply, generally designated 312, is suitably located externally of the container 300 and has one output terminal (e.g., the ground terminal) connected to the metal container 300, and a second output terminal (e.g., the minus-terminal ) connected to electrode 302.

As one example, container 300 may be a circular steel fuel container having an inner diameter of about 10 cm and adapted to receive fuel to a level close to the top of the container. Electrode 302 may be a nickel-chromium wire of 1 mm in diameter and insulated by a Pyrex glass sleeve 310. The exposed tip 302b of electrode 302 may have a length of about 10 mm and directed at an angle of about 45° towards the longitudinal axis of the container, at a height of about 15-20 mm above the container edge, and about 0-15 mm iside the container periphery. Stand 304 may be of suitable insulating material, such as PVC.

The high voltage power supply 312 may generate either a continuous DC output, or a pulsed DC output, of 20-25 kV, with a minimum duration of about 150 ms . Its minus-terminal may be connected to electrode 302, -and its ground-terminal may be connected to metal container 300, or vice versa.

The energization of the high voltage from the power supply 312 may be initiated automatically in response to the detection of a fire by a fire detector (not shown), or manually. The current during an extinguishing operation may be about 1 00 to 600 miliamps .

Fig. 3 illustrates the apparatus of Fig. 2 applied to protect a plurality of fuel containers 401 , 402 , 403 . As in Fig. 2 , each of the containers 401 - 403 is also of metal and serves as one electrode of the airgap across which the intense electromagnetic field is produced to extinguish a fire that may occur in the liquid of the container. The second electrode of each such airgap is indicated at 402a- 402c , respectively, and each is supported by a stand 404a- 404c permitting vertical and horizontal adjustment of its respective electrode, as described with respect to Fig. 2 . A high voltage supply 41 2 , common to all the containers 401 - 403 , includes an output terminal connected to all the containers, and another output terminal connected to all the second electrodes 402a- 402c , so that all the airgaps are connected in parallel to the high voltage supply.

In all other respects, the multi-container system illustrated in Fig. 3 is constructed and operates in substantially the same manner as described above with respect to Fig. 2 .

Claims (10)

94367/3 - 9 - WHAT IS CLAIMED IS:

1. Apparatus for extinguishing a fire according to Claims 5 and 6 of Israel Patent No.92951, wherein the generator and directing means are carried by a portable manually-actuated unit.

2. The apparatus according to preceding Claim 1 , wherein said portable manually-actuated unit includes a handle and said voltage applying means adjacent one end, said airgap defined by said electrodes adjacent the opposite end, and said generator between said handle and said airgap.

3. The apparatus according to preceding Claim 2, wherein said handle includes a first handgrip at said one end, and a second handgrip spaced from said first handgrip towards said opposite end.

4. The apparatus according to preceding Claim 3, wherein said portable manually-actuated unit comprises an elongated member carrying said first and second handgrips adjacent one end thereof, said two electrodes defining said airgap adjacent the opposite end thereof, and said high voltage source at an intermediate location therebetween.

5. The apparatus according to preceding Claim 4, wherein one of said electrodes extends from said high voltage source substantially coaxially with said elongated member, and the other of said electrodes 94367/3 - 10 - extends from said high voltage source laterally thereof but is bent in the general axial direction to terminate adjacent the end of said one electrode to define said airga .

6. Apparatus according to Claims 5 and 6 of Patent No.92951, wherein said airgap is. located adjacent the top of a container for an inflammable liquid.

7. The apparatus according to Claim 6, wherein the container is of metal and serves as one electrode of said airgap, the other electrode of said airgap being disposed in air above the liqud level in the container and having a tip within the periphery of the container.

8. The apparatus according to preceding Claim 7, wherein said second electrode is mounted on an insulating member externally of the container and includes a conductor overlying the top of the container and extending inwardly thereof at an oblique angle to the longitudinal axis of the container.

9. The apparatus according to any one of preceding Claims 6-8, wherein said apparatus is used with a plurality of containers and includes a plurality of said second electrodes each defining an airgap between it and the respective container, the plurality of airgaps being connected in parallel to said high voltage source.

10. Apparatus for extinguishing a fire substantially as described with reference to and as illustrated in the accompanying drawings. Advocate, Patent Attorney Beit Amot Mishpat 8 Shaul Hamelech Boulevard 64733 Tel Aviv