The present invention relates generally to a fire fighting nozzle and a method of detecting if a remote electric supply is in electrical contact with the nozzle and finds particular, although not exclusive, utility in protecting firemen from being electrocuted.

Fire fighters typically used foam or water emitted at relatively high pressure via fire hoses and nozzles to extinguish fires. Electrical supplies in properties and electric cars are not always isolated before this occurs and with the increasing predominance of electricity generating PV panels on property roofs there is a risk that fire fighters may be electrocuted by a current passing along the flow of fluid emitted from the nozzle. Even though the fire fighter may be insulated from earthed objects, such as the ground, static electricity can build up leading to an unpleasant and sometimes dangerous discharge when the fire fighter eventually does come into contact with an earthed object.

It is desirable to reduce the risk of electrical currents or voltages from reaching the fire fighter in the first place. It is also desirable to provide an indication that a voltage has been detected, in case the voltage does unfortunately reach the fire fighter, such that they may take measures to earth themselves safely.

I a first aspect, the invention provides a fire fighting nozzle for emitting a fluid for fighting fires, the nozzle arranged to emit the fluid in pulses via a passageway, the nozzle comprising a barrel, located in the passageway, the barrel including an aperture to allow the fluid to pass through the passageway with the barrel in a first position, and a vane for blocking the flow of fluid with the barrel in a second position, the barrel arranged to spin due to the force exerted by the fluid, in use, so as to alternate between the first and second positions.

In this manner, the stream of fluid becomes interrupted such that neither an electrical current nor voltage may reach the nozzle. The nozzle may be connectable to a hose and may include standard fittings for attaching it thereto.

The barrel may be designed such that the number of vanes and/ or apertures is chosen as required. In one example, the barrel may include more than one vane and more than one aperture. This will typically result in shorter pulses of fluid but emitted more frequently.

The nozzle and/or barrel may include an adjustable brake such that the rotational speed of the barrel may be adjusted.

The fire fighting nozzle may further comprise a voltage detector for providing an indication that the fluid is in contact with a source of electricity. The indication may be in the form of a sound (such as a buzzer) or visual signal (such as a light). The voltage detector may be an electrostatic voltmeter. In this manner, the voltage detector may include a sensor which is arranged such that it will sense a voltage in the fluid and/ or the nozzle without necessarily having to be in contact with the voltage.

The voltage detector may be useful in situations where the pulsing of the fluid has failed to isolate the nozzle from a source of electricity. For instance this may occur where a fine spray of fluid exists between the pulses due to air movement in the vicinity, or for other unexpected situations.

The voltage detector may be attachable to the end of the nozzle where the fluid is emitted. However, it may be attachable to the nozzle at other locations. It may be attachable to a hose which is connected to the nozzle. The voltage detector may include a clamp for removably attaching it to the nozzle and/or hose.

The voltage detector may be arranged to detect either or both AC and DC supplies.

In a second aspect, the invention provides a method of detecting if a remote electric supply is in electrical contact with a fire fighting nozzle comprising the steps of providing a fire fighting nozzle according to the first aspect, connecting the nozzle to a supply of pressurised fluid, operating the nozzle to emit the fluid and monitoring the voltage detector for an indication as to whether or not the fluid is in contact with a source of electricity.

The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. This description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

Figure 1 is an elevational view of a fire nozzle;

Figure 2 is an exploded perspective view of the nozzle of Figure 1;

Figure 3 is a cross-sectional view through a barrel forming part of the nozzle; and

Figure 4 is a perspective view of the barrel.

The present invention will be described with respect to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. Each drawing may not include all of the features of the invention and therefore should not necessarily be considered to be an embodiment of the invention. In the drawings, the size of some of the elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequence, either temporally, spatially, in ranking or in any other manner. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other sequences than described or illustrated herein. Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other orientations than described or illustrated herein.

It is to be noticed that the term "comprising", used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression "a device comprising means A and B" should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B.

Reference throughout this specification to "an embodiment" or "an aspect" means that a particular feature, structure or characteristic described in connection with the embodiment or aspect is included in at least one embodiment or aspect of the present invention. Thus, appearances of the phrases "in one embodiment", "in an embodiment", or "in an aspect" in various places throughout this specification are not necessarily all referring to the same embodiment or aspect, but may refer to different embodiments or aspects. Furthermore, the particular features, structures or characteristics of any embodiment or aspect of the invention may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments or aspects.

Similarly, it should be appreciated that in the description various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Moreover, the description of any individual drawing or aspect should not necessarily be considered to be an embodiment of the invention. Rather, as the following claims reflect, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, while some embodiments described herein include some features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form yet further embodiments, as will be understood by those skilled in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

In the description provided herein, numerous specific details are set forth.

However, it is understood that embodiments of the invention may be practised without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

In the 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 said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

The use of the term "at least one" may mean only one in certain circumstances. The principles of the invention will now be described by a detailed description of at least one drawing relating to exemplary features of the invention. It is clear that other arrangements can be configured according to the knowledge of persons skilled in the art without departing from the underlying concept or technical teaching of the invention, the invention being limited only by the terms of the appended claims.

In Figure 1 the nozzle 10 comprises an approximately cylindrical body 20 having a connection means 40 at one axial end for connecting it to a source of pressurised fluid and an outlet 30 at the opposite axial end. A handle 50 for gripping by the user is provided approximately mid-way along the axial length of the body 20 which extends away perpendicularly.

An exploded view of the nozzle 10 is shown in Figure 2. The connection means 40 includes an ' 0' ring 42 to sealingly connecting the body 20 to a hose (not shown).

A central section 35 of the body 20 includes a chamber 36 into which a barrel 37 is insertable. The barrel 37 is approximately cotton-reel in shape having 2 opposite end walls 31 and a cylindrical portion therebetween. The cylindrical portion includes at least one solid radial wall 38 and at least one removed section/ segment 38 as will be explained in more detail below.

In the nozzle 10 a passageway or bore (not shown) extends within the body

20 from the connection means 40 to the outlet 30. The chamber 36 is cylindrical in shape having a diameter slightly larger than the barrel 37 such that the barrel may rotate freely within it. Where the bore meets the chamber 36 it is arranged such that it occupies only a portion of the side wall of the chamber 36. The portion is equal to or smaller than the radius of the barrel 37 and is arranged such that it is to one side of the longitudinal axis of the barrel 37 with the barrel inserted into the chamber. In this way, with the fluid passing through the chamber 36 it acts against only one side of the barrel thus rotating it.

The chamber 36 includes a door 33 to seal it when in use. An axle 32 in the form of a pin passes through the longitudinal axis of the barrel 37 and is held in place at each end by detentes provided in the door 33 and far side of the chamber 36.

In Figure 3 a cross-section through the barrel 37 along the lines A-A' (as indicated in Figure 4) is shown.

Figure 4 shows a perspective view of the barrel 37.

Taken together it can be seen that the barrel has two segments 39 removed between the two radial end plates 31 opposite one another. By contrast, the portions 38 between these removed segments 39 have their circumferential outer faces located approximately equal to the circumference of the end plates 31.

Walls 60 connect radially from the approximate axial centre of the barrel to the circumferential outer faces. These walls 60 may be described as "vanes".

The angle of the arc of each removed sections 39 is approximately 90 degrees although other angles are contemplated such as in the range 30 to 180 degrees.

It is contemplated that the barrel may have only one removed section 39, or more than two removed sections.

A friction brake in the form of a pad movable toward and away from an end plate or other portion of the barrel may be included to slow the rotational speed of the barrel. A brake controller may be provided for a user to operate.