GB2479885A

GB2479885A - A fire fighting lance

Info

Publication number: GB2479885A
Application number: GB201006993A
Authority: GB
Inventors: Paul Baker
Original assignee: PARK LODGE INTERNAT Ltd
Current assignee: PARK LODGE INTERNAT Ltd
Priority date: 2010-04-27
Filing date: 2010-04-27
Publication date: 2011-11-02
Anticipated expiration: 2030-04-27
Also published as: GB201006993D0; GB2479885B

Abstract

A fire fighting lance 10 comprising an inlet 16 for receiving pressurised water, an outlet 18 for dispensing a stream of pressurised water towards a target and a conduit 12 connecting the inlet 16 to the outlet 18, wherein the fire fighting lance 10 further comprises a vessel 26, mounted on the lance 10 for containing abrasive material, and means for releasing abrasive material from the vessel 26 into a stream of pressurised water flowing from the inlet 16 to the outlet. Abrasive may be delivered by gravity feed and the conduit may include a reduced diameter to enable the abrasive material to be drawn in by the Venturi effect. The outlet may further comprise an end plate having a shield to direct the water away from the user, projecting feet to stabilize the lance in operation, wherein the plate is pivotally attached to the outlet of the lance.

Description

A FIRE FIGHTING LANCE

Technical Field

The present invention relates to a fire fighting lance.

Background to the Invention

It is well known that the phenomenon of backdraft presents one of the greatest dangers to fire fighters tackling a fire. Backdraft occurs when a fire is starved of oxygen, typically because the fire has broken out in an enclosed space and has consumed all of the available oxygen in the space. As a result of this oxygen starvation, combustion ceases, but the temperature in the enclosed space remains extremely high, and combustible gases remain present. If oxygen is reintroduced into the space, for example when a door is opened by a fire fighter, the combustible gases can reignite due to the extreme heat. As they reignite, the combustible gases expand, causing a sudden and explosive effect.

Equipment has been developed to reduce the risk to fire fighters when tackling a fire in an enclosed space. One example of such equipment includes a hand-held lance, which is an elongate generally rigid conduit having an inlet for pressurised water and an outlet through which a narrow stream of high pressure water can be supplied to a target such as to an exterior wall, door or the like of the enclosed space. An abrasive material such as small particles of garnet is injected into the stream of pressurised water from a vessel, and the combination of the high pressure water and the abrasive material creates a hole in the target exterior wall, door or the like, through which a fine mist of water can be sprayed to radically reduce the temperature inside the enclosed space rapidly, whilst also starving flames of oxygen, to remove the risk of backdraft and potentially to extinguish the fire.

Existing equipment of this type typically includes a pressurised vessel for storing the abrasive material and dispensing it into the stream of pressurised water flowing through

I

the conduit, with the pressurised vessel being positioned at some distance from the lance, for example on a fire appliance such as a fire engine or the like. This arrangement requires complex and lengthy pipework to direct the abrasive into the stream of pressurised water, and is thus difficult and costly to manufacture and maintain. Moreover, the length of pipework required to supply the abrasive to the stream of pressurised water delays the abrasive from entering the stream of pressurised water and ultimately hitting the target, which leads to avoidable delays in temperature reduction and the consequent removal of the risk of backdraft.

Summary of Invention

According to a first aspect of the present invention there is provided a fire fighting lance comprising an inlet for receiving pressurised water, an outlet for dispensing a stream of pressurised water towards a target and a conduit connecting the inlet to the outlet, wherein the fire fighting lance further comprises a vessel mounted on the lance for containing abrasive material and means for releasing abrasive material from the vessel into a stream of pressurised water flowing from the inlet to the outlet.

Mounting the vessel on the lance facilitates manufacture and maintenance of the lance, as complex pipework is not required to direct the abrasive material into the stream of pressurised water, whilst also reducing the time taken for the abrasive material to reach the target, thereby reducing the time taken to pierce or penetrate the target and radically reducing the temperature within the interior of the target thereby facilitating conventional fire fighting when necessary without the risk of backdraft.

The vessel of the fire fighting lance may be mounted on the lance such that in operation of the lance abrasive material is released into the stream of pressurised water under the action of gravity.

The vessel may be shaped so as to impede ingress of water into the vessel.

For example, a roof of the vessel may be curved.

Additionally or alternatively, the vessel may be pressurised.

The vessel may be mounted at an angle with respect to the conduit.

The conduit may be provided with a reduced diameter section so as to create a Venturi effect such that when pressurised water flows through the conduit a vacuum is created which draws abrasive material into the stream of pressurised water.

The fire fighting lance may further comprise means for adjusting a rate of release of abrasive material into the stream of pressurised water.

The fire fighting lance may further comprise a manually operable trigger for controlling the flow of water through the conduit.

Advantageously the trigger is biased towards a closed position in which water cannot flow through the conduit.

The fire fighting lance may further comprise an end plate associated with the outlet, the end plate having a shield which is shaped to direct water reflected from a target of the lance away from an operator of the lance.

For example, the end plate may comprise a shield section which extends outwardly of an upper part of the end plate in a plane substantially parallel to an axis of the outlet.

The end plate may further comprise projecting feet which engage with a target of the lance to stabilise the lance in operation.

The end plate may be pivotally mounted with respect to the outlet of the lance.

Preferably, the vessel is refillable.

The vessel may be replaceable.

Brief Description of the Drawings

Embodiments of the invention will now be described, strictly by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a schematic representation of a fire fighting lance according to one embodiment of the present invention; Figure 2 is a schematic representation of a vessel for the fire fighting lance shown in Figure 1; Figure 3 is a schematic cross-sectional view showing first and second conduits of the fire fighting lance of Figure 1; Figure 4 is a schematic cross-sectional view of an outlet portion of the fire fighting lance of Figure 1; Figure 5 is a schematic end view of an end plate for the fire fighting lance shown in Figure 1; Figure 6 is a schematic representation of a handle for the fire fighting lance shown in Figure 1; Figure 7 is a schematic cross sectional view showing a trigger mechanism for the fire fighting lance shown in Figure 1; and Figure 8 is a schematic representation of an alternative embodiment of a fire fighting lance.

Description of the Embodiments

Referring first to Figure 1, a fire fighting lance is shown generally at 10, and comprises a generally hollow first conduit 12 having at one end thereof a handle 14 which permits the lance 10 to be held in the hand of an operator. A shoulder pad is also provided on a mounting which extends rearwardly of the lance 10 and permits the lance to be braced against a shoulder of a user for stability, whilst allowing the user to hold the lance 10 in both hands by the handle 14 and a forward handle which is described below. For reasons of clarity the shoulder pad is not illustrated here, but it will be appreciated that a shoulder pad of the type used in lances of pressure washers and the like is well suited to the lance of the present invention.

The lance 10 has an inlet 16, which in this example is provided at a lower part of the handle 14. The inlet 16 communicates with the first conduit 12 such that pressurised water from a source external to the lance 10 can enter the first conduit 12.

An outlet 18 is provided at an end of the first conduit 12 distal from the handle 14, through which pressurised water can be directed onto a target such as an exterior wall, door or the like of a building or other structure. The outlet in this example is a ceramic nozzle with a bore of approximately 1.6mm diameter. This diameter of bore has been found to produce a suitably narrow jet of pressurised water, but it will be appreciated that alternative bore diameters may be employed.

A second conduit 20 is provided, which second conduit 20 is disposed above the first conduit 12 when the lance 10 is in a generally horizontal orientation as shown in Figure 1. A first end of the second conduit 20 is attached to the first conduit 12 towards the outlet 18 of the first conduit 12, and communicates with the first conduit 12. An inlet 22 is provided towards a second end of the second conduit 20, which inlet 22 communicates with an outlet 24 of a vessel 26.

The vessel 26, which is illustrated in more detail in Figure 2, is used to store abrasive material such as small particles of garnet, ferrous oxide or the like, and mounted on the lance 10 in a position in which it is disposed above the second conduit 20 when the lance is in a generally horizontal orientation as shown in Figure 1. The vessel 26 may be removably attached to the lance 10, to permit rapid and simple replacement of the vessel

26 in the field.

The outlet 24 of the vessel 26 may be provided with means for regulating or adjusting the flow rate of the abrasive material from the vessel 26. For example, the outlet 24 may be provided with a threaded collar 27 which engages with an exterior wall of the outlet 24 and can be tightened or loosened to reduce or increase the diameter of an aperture defined by the outlet 24. Alternatively, means for regulating or adjusting the flow rate of the abrasive material may be provided elsewhere, for example as a valve or tap in the second conduit 20.

The vessel 26 is provided with a filling inlet 28 for filling the vessel 26 with the abrasive material. In the example shown in Figure 1 the filling inlet 28 is provided in a roof 30 of the vessel 26, as this facilitates filling the vessel 26, but it will be appreciated that the filling inlet 28 may be provided elsewhere.

The filling inlet 28 is closed by a cap 32, which may be secured to the vessel 26 by engagement of an internal screw thread of the cap 32 with an external screw thread of the filling inlet 28, or by any other suitable means. The cap 32 is provided with a seal such that when the cap 32 is secured to the filling inlet 28 a watertight seal is provided to impede the ingress of water into the vessel 26. To further impede ingress of water into the vessel 26 the roof 30 of the vessel may be slightly curved or convex, to promote the flow of water away from the filling inlet 28.

The vessel 26 is also provided with an air intake 34 to permit air to enter the vessel 26 as the abrasive material stored therein is released through the outlet 24.

As is shown in Figure 3, the first conduit 12 is provided with a reduced diameter section 36, close to a point at which the second conduit 20 is connected to the first conduit 12.

The reduced diameter section 36 may be formed, for example, by baffles 38 positioned in an interior of the first conduit 12. The reduced diameter section 36 acts as a Venturi valve when pressurised water is flowing through the first conduit 12, creating a partial vacuum downstream of the reduced diameter section 36 where the second conduit 20 connects to the first conduit 12, and this vacuum acts to draw abrasive material from the vessel 26 into the stream of pressurised water flowing through the first conduit 12. Thus, at the outlet 18 of the lance 10 a stream of pressurised water containing particles of the abrasive material can be produced.

A forward handle 39 mounted on the first conduit 12 of the lance 10 includes a release mechanism for releasing the abrasive material into the stream of pressurised water flowing through the first conduit 12. The release mechanism may be, for example, a mechanical mechanism which is operative to open a valve in the second conduit 20 or in the outlet 24 of the vessel 26.

Figure 4 is a schematic view of an outlet end portion of the fire fighting lance 10 shown in Figure 1. The outlet end portion is shown generally at 40 and includes the outlet 18, which as previously described may be a ceramic nozzle with a bore 42 of approximately 1.6 mm diameter, such that the lance 10 may direct a high pressure jet 46 of water containing abrasive particles towards a target 48 such as an exterior wall, door or the like of a building or other structure.

An end plate 50 is mounted on the outlet end portion 40 of the lance 10 and is associated with the outlet 18. In this example the end plate 50 is a generally pentagonal plate mounted directly on the outlet 18, but it will be appreciated that other shapes and mounting arrangements are possible. The end plate 50, which is also illustrated in an end view in Figure 5, has upper and lower feet 52, 54, by means of which the lance 10 can be securely engaged with the target 48 to prevent or impede movement of the lance 10, and in particular the outlet 18, in use of the lance 10, to ensure that the pressurised jet of water containing the abrasive is constantly directed towards the same point on the target 48, thus minimising the time taken to penetrate the target 48. To assist in this the feet 52, 54 are formed as or are provided with pointed formations which can dig in to the target 48.

To impede water reflected from the target 48 from spraying back towards the operator of the lance 10 or the vessel 26, the end plate 50 is provided with a shield 56 which extends outwardly around an upper part of the end plate 50 in a direction generally parallel to a longitudinal axis of the outlet 18, thereby forming a physical barrier for water reflected from the target 48. In this example the shield 56 is associated with the upper feet 52, but it will be appreciated that other configurations are possible. The end plate 50 itself is shaped to promote water to flow towards the ground, having in this example a sloped portion 58 to direct water deflected by the shield 56 towards the ground.

To permit an operator of the lance 10 to direct the jet of water from the outlet 18 in use of the lance 10, the end plate 50 may be pivotally mounted to the outlet 18 or the first conduit 12, for example by means of a ball joint. Using this arrangement, the lance 10 can be securely engaged with the target 48, and can subsequently be rotated or otherwise manoeuvred to cut complex shapes in the target 48. This can help in cutting victims free from vehicles that have been involved in road traffic accidents, for example.

Figure 6 shows the handle 14 of the lance 10 in more detail. The handle 14 is hollow such that pressurised water from a source external to the lance 10 can flow from the inlet 16 to an outlet 60, which communicates with the second conduit 20. The handle 14 is provided with a trigger 62 for controlling the flow of water through the conduit. The trigger 62 is biased towards a closed position, as will be explained in more detail below, and is provided with a safety catch 64 which can be engaged with the trigger 62 to prevent accidental operation of the lance 10.

Figure 7 is a schematic representation of a trigger mechanism for the fire fighting lance 10. The trigger mechanism is shown generally at 70 and includes the trigger 62 shown in Figure 6. The trigger 62 takes the form of a generally elongate member which is pivotally mounted on a pivot 72. A projecting arm 74 is attached to or integral with the elongate member of the trigger 62, and projects outwardly thereof The projecting arm 74 is configured to pivot with the trigger 62 about the pivot 72. A distal end 76 of the projecting arm 74 pivotally connected to or otherwise receives an actuator 78 of a valve 80, which valve 80 is mounted in the first conduit 12 of the lance 10 and is operative to control the flow of water through the first conduit 12.

The piston valve 80 has a closure member 82 which is mounted on the actuator 78. A compression spring 84 is provided between an outer surface of the closure member 82 and a body 86 of the trigger mechanism 70, and is operative to bias the valve 80 towards a closed position in which water cannot flow through the first conduit 12, by urging the closure member 82 towards a position in which it blocks the first conduit 12.

When the trigger 62 is pulled or squeezed by an operator of the lance 10, it moves in the direction of arrow 88, causing a corresponding rotary movement of the projecting arm 74, which in turn causes a linear movement of the actuator 78 in the direction of arrow 90, against the bias of the compression spring 84. This causes the closure member 82 to move out of its initial closed position, creating an aperture through which water is able to flow through the conduit. It will be appreciated that the greater the movement of the trigger 62, the greater the movement of the closure member 82 and thus the larger the aperture through which water is able to flow. Thus, the trigger 62 can be used to regulate the amount of water flowing through the first conduit 12. When the trigger 62 is released, the closure member 82 returns to its initial closed position under the action of the compression spring 84, closing the aperture and thus stopping the flow of water through the aperture and the first conduit 12. The projecting arm 74 and the trigger 62 also return to their at rest positions.

Referring now to Figure 8, an alternative embodiment of a fire fighting lance is shown generally at 100. The lance 100 includes a generally hollow first conduit 102 having an inlet 104 at one end, through which pressurised water from a source external to the lance can be introduced into the first conduit 102. The first conduit 102 terminates in an outlet 106 through which pressurised water can be directed towards a target such as an exterior wall, door or the like of a building or other structure. As in the embodiment illustrated in Figure 1, the outlet 106 may be a ceramic nozzle having a bore of approximately 1.6mm in diameter. An end plate of the type described above with reference to Figures 4 and 5 is associated with the outlet 106 of the lance 100.

In this embodiment a pressurised vessel 110 is provided for storing an abrasive material such as small particles of garnet, aluminium oxide or the like. The vessel 110 is mounted on a support 112 which is angled with respect to the first conduit 102. In this example the support 112 is angled at approximately 45 degrees with respect to the first conduit 102, as this is believed to provide a wide range of operational angles for the lance 100. For example, the lance 100 can be used in a generally horizontal orientation, as shown in Figure 8, or can be angled upwardly to target ceilings, or downwardly to target floors. As in the embodiment illustrated in Figure 1, the vessel 110 is refillable and replaceable.

The vessel 110 has an outlet 114 which communicates with a second conduit 116 which depends from the first conduit 102. A distal end of the second conduit 116 is attached to the first conduit 102 towards the outlet 106 of the first conduit 102 and communicates with the first conduit 102. As the vessel 110 in this embodiment is pressurised there is no need for a reduced diameter section in the first conduit 102 to create a Venturi effect vacuum which draws abrasive material into the flow of water passing through the first conduit 102. However, to improve the efficacy of the lance 110, such a reduced diameter section may be provided in the first conduit upstream of the point at which the second conduit 116 is attached to the first conduit 102.

The lance 100 is provided with a trigger 118 for controlling the flow of water through the first conduit 102. The lance 100 may employ a trigger mechanism as described above with reference to Figure 7, and thus as in the embodiment illustrated in Figure 1, the trigger 118 is biased towards a closed position, and is provided with a safety catch which can be engaged with the trigger 118 to prevent accidental operation of the lance 10.

The lance 100 is provided with a forward handle 120 which is mounted on the first conduit 102 of the lance 100 and includes a release mechanism for releasing the abrasive material into the stream of pressurised water flowing through the first conduit 102. The release mechanism may be a mechanical mechanism which is operative to open a valve in the second conduit 116 or in the outlet 114 of the vessel 110.

In use of the lance 10, 100, the inlet 16, 104 is connected to an external source of pressurised water, such as a fire appliance, and a release rate for the abrasive material appropriate to the situation is selected using the adjustment means. For example, if the lance 10, 100 is being used to combat a fire in a concrete-walled building a greater abrasive flow rate may be required than if the lance 10, 100 is being used to combat a fire in a wooden shed. The feet 52, 54 of the end plate 50 are engaged with the target 48, which may be an exterior wall of burning building, and the trigger 62, 118 is squeezed to release pressurised water towards the target 48. At an appropriate time the release mechanism is actuated, causing abrasive material to be released into the stream of water flowing through the first conduit 12, 102 and out of the outlet 18, 106. The stream of pressurised water containing the abrasive material punctures the target, allowing a fine stream of water in the form of a fine mist to be sprayed through the resulting hole in the target, which rapidly cools the interior of the building, whilst starving flames within the building of oxygen so as, potentially, to extinguish them.

It will be appreciated from the foregoing that the fire fighting lance 10, 100 of the present invention provides a means for significantly improving the safety of fire fighters, as it rapidly and radically reduces the extremely high temperatures, which increase the risk of backdraft, in the interior of a target such as a burning building from the exterior of the target. In this way, fire fighters need not enter the building to fight the fire, and if it becomes necessary to do so the risk of backdraft is eliminated. Providing the vessel 26, as part of the lance 10, 100, facilitates manufacture and maintenance of the lance 10, 100, and reduces the time taken for the abrasive material to reach the target, thereby reducing the time taken to pierce or penetrate the target and accelerating the process of cooling the interior of the target and potentially extinguishing the fire.

Claims

CLAIMS1. A fire fighting lance comprising an inlet for receiving pressurised water, an outlet for dispensing a stream of pressurised water towards a target and a conduit connecting the inlet to the outlet, wherein the fire fighting lance further comprises a vessel mounted on the lance for containing abrasive material and means for releasing abrasive material from the vessel into a stream of pressurised water flowing from the inlet to the outlet.
2. A fire fighting lance according to claim 1 wherein the vessel is mounted on the lance such that in operation of the lance abrasive material is released into the stream of pressurised water under the action of gravity.
3. A fire fighting lance according to claim 2 wherein the vessel is shaped so as to impede ingress of water into the vessel.
4. A fire fighting lance according to claim 3 wherein a roof of the vessel is curved.
5. A fire fighting lance according to claim 1 wherein the vessel is pressurised.
6. A fire fighting lance according to claim 5 wherein the vessel is mounted at an angle with respect to the conduit.
7. A fire fighting lance according to any one of the preceding claims wherein the conduit is provided with a reduced diameter section so as to create a Venturi effect such that when pressurised water flows through the conduit a vacuum is created which draws abrasive material into the stream of pressurised water.
8. A fire fighting lance according to any one of the preceding claims further comprising means for adjusting a rate of release of abrasive material into the stream of pressurised water.
9. A fire fighting lance according to any one of the preceding claims further comprising a manually operable trigger for controlling the flow of water through the conduit.
10. A fire fighting lance according to claim 9 wherein the trigger is biased towards a closed position in which water cannot flow through the conduit.
11. A fire fighting lance according to any one of the preceding claims further comprising an end plate associated with the outlet, the end plate having a shield which is shaped to direct water reflected from a target of the lance away from an operator of the lance.
12. A fire fighting lance according to claim 11 wherein the end plate comprises a shield section which extends outwardly of an upper part of the end plate in a plane substantially parallel to an axis of the outlet.
13. A fire fighting lance according to claim 11 or claim 12 wherein the end plate further comprises projecting feet which engage with a target of the lance to stabilise the lance in operation thereof.
14. A fire fighting lance according to claim 13 wherein the end plate is pivotally mounted with respect to the outlet of the lance.
15. A fire fighting lance according to any one of the preceding claims wherein the vessel is refillable.
16. A fire fighting lance according to any one of the preceding claims wherein the vessel is replaceable.
17. A fire fighting lance substantially as hereinbefore described with reference to the accompanying drawings.