Fire blower apparatus

Abstract

A fire blower apparatus is provided for promoting combustion of a fire. The apparatus comprises a hollow elongate tubular member having an inlet port comprising a mouthpiece positioned proximate an upstream end thereof for receiving an oxygen-containing gas, and an adjustable gas outlet assembly comprising an adjustable nozzle assembly positioned proximate a downstream end thereof. The nozzle assembly comprises a nozzle and an adjustable gas flow restriction mechanism configured to restrict the oxygen-containing gas from passing through the nozzle. The nozzle assembly may be arranged to provide adjustment of either or both a variable bore shape and an internal volume of the nozzle. A method of manufacturing the fire blower apparatus is also described, in which one or more components of the nozzle assembly may be subjected to a heating step.

Description

[0001] FIRE BLOWER APPARATUS

[0002] CROSS-REFERENCE TO RELATED APPLICATION

[0003] This application claims priority from South African provisional patent application number 2023 / 08880 filed on 20 September 2023, which is incorporated by reference herein.

[0004] FIELD

[0005] This disclosure relates to the promotion of combustion of fires, coals, embers and the like by directing air or other oxygen-containing gases into them.

[0006] BACKGROUND

[0007] Combustion is a chemical reaction between substances, usually including oxygen and often accompanied by the generation of heat and light in the form of a flame. The rate at which the reactants combine, or combustion occurs is high. This high rate of combustion is in part because of the nature of the chemical reaction itself and in part because as the energy is generated and escapes into the surrounding burning medium or fuel, it results in an increased temperature of the reactants which in turn accelerates the combustion reaction.

[0008] Combustion of a flammable fuel such as charcoal, coal, wood, paper or other combustible materials to create a fire or a flame requires specific factors or circumstances to ensure successful and efficient combustion. The most important factors for successful combustion include 1 ) the provision of fuel or other combustible material, 2) an oxygen source and 3) a source of ignition if the combustible material is not already burning i.e. a heat source. Fire extinguishing factors, include lowered oxygen provision or oxygen starvation (that is, smothering) or conversely an oversupply of high-speed airflow (such as a high wind). These undesirable factors, along with others, can ultimately extinguish a fire by reducing the rate of active combustion. A lower rate of combustion has the further unwanted side effect of causing smoke to be generated. Increasing the flow of air or oxygen to a combustion reaction can prevent it from dying or enhance the combustion and reduce smoke generation.

[0009] Therefore, in certain instances it may be necessary to increase the oxygen in the air surrounding a combustion reaction or a region of it. Every wood, coal or similarly fuelled fire has one or multiple regions or centres in which heat is concentrated. These combustion centres require the most oxygen but can be the most oxygen -starved parts of a fire or combustion reaction because of the high rate of combustion or the low oxygen supply found in these regions. The combustion centre is thus a critical element for sustaining combustion of a fire or flame, and an oxygen -starved combustion centre or central region of a combustion reaction may cause a fire to be extinguished. Concentrating oxygen precisely to where it is needed, that is, to the so-called combustion centre, results in more efficient use of energy in relation to the effort necessary to create air pressure and move air.

[0010] Current solutions to oxygen starvation when combusting a fuel include blowing on a fire with a user’s mouth, bellows, fire fans, hand crank bellows and rotating impellers or propeller fan blades. Some applications require faster moving, but a lower volume of air, while other applications require slower acceleration but a greater total volume of air per time period. The current solutions do not provide this range of oxygen provision to the combustion reaction, and for the most part all provide very little control over the volume, angle, and velocity of air expelled from the apparatuses. Current methods used to counteract oxygen starvation when combusting a fuel may accordingly be insufficient to supply oxygen directly and precisely to the oxygen-starved combustion centres where the oxygen is most needed.

[0011] The preceding discussion of the background is intended only to facilitate an understanding of the present disclosure. It should be appreciated that the discussion is not an acknowledgment or admission that any of the material referred to was part of the common general knowledge in the art as at the priority date of the application.

[0012] SUMMARY

[0013] According to an aspect of the disclosure there is provided a fire blower apparatus for promoting combustion of a fire, the apparatus comprising at least one hollow elongate tubular member having an inlet port positioned proximate an upstream end thereof for receiving an oxygencontaining gas, and an adjustable gas outlet assembly positioned proximate a downstream end thereof and configured to regulate gas flow through the gas outlet assembly.

[0014] The gas outlet assembly may include an adjustable nozzle assembly. The adjustable nozzle assembly may include a nozzle and an adjustable gas flow restriction mechanism configured to restrict the oxygen-containing gas from passing through the nozzle.

[0015] The upstream gas inlet port may comprise a mouthpiece.

[0016] The oxygen-containing gas may be air. The adjustable nozzle assembly may be configured to permit adjustment of one or more parameters independently selected from the group consisting of: a volume of air passing through the nozzle for a given pressure of said volume of air applied at the inlet port; a velocity of the air passing through the nozzle; an exit angle of air emerging from the nozzle; and a shape or pattern of a volume of air emerging from the nozzle. The shape or pattern may range from a spread-out shape to a narrow jet of reduced diameter. The adjustable nozzle assembly may be arranged to provide adjustment of either or both a variable bore shape and an internal volume of the nozzle. The adjustable nozzle assembly may be configured to permit tool-free manual adjustment of any one or more of the above parameters independently from one another or in combination with one another.

[0017] The adjustable nozzle assembly may comprise a first member and a second member configured to be movable relative to the first member; a nozzle inlet configured to receive air from the elongate tubular member, and a nozzle outlet configured to expel air; and at least one of the first and second members may comprise an obstructing means configured at least partially to obstruct the nozzle outlet when the first and second members are displaced relatively to each other. These components together may make up the gas flow restriction mechanism.

[0018] The obstructing means may be configured to adjust internal dimensions of the nozzle outlet. The obstructing means may extend from, or be integrated with, one of the first and second members. The obstructing means may be fixed relative to the elongate tubular main body.

[0019] The adjustable nozzle assembly may define an inlet aperture and an outlet aperture of reduced cross-sectional area relative to that of the inlet aperture. The nozzle outlet may be tapered, defining an internal cavity shaped to receive the obstructing means, e.g. the tip of a complementary or cooperating pin formation configured to nest flush with an internal wall of the nozzle outlet when the pin is advanced to an extended position. The nozzle outlet may define a frustoconical internal wall having a wall angle in a range from about 20eto about 75erelative to a principal axis of the nozzle assembly.

[0020] At least one of the first and second members of the nozzle assembly may comprise an internal body or nozzle base comprising the pin formation. The internal body and pin formation may be of unibody construction, that is, they may be integrated with each other. This arrangement may be referred to as a “floating pin”.

[0021] The first and second members may comprise complementarily threaded or screwed components. The components may be configured to define a plenum for receiving and constricting gas flow received into the nozzle assembly from the inlet port. At least one of the first and second members may comprise a turning body and the pitch of the thread may be configured to provide that one full rotation of the turning body shall cause the adjustable nozzle assembly to be adjusted from a fully closed condition to a fully open condition.

[0022] The adjustable nozzle assembly may be configured such that displacement of the first and second members relatively to each other is obtained by rotation, telescoping, or sliding of one of the members relatively to the other.

[0023] The fire blower apparatus may include an indicator apparatus. This may be provided as part of the adjustable nozzle assembly or as a cooperative arrangement between the nozzle assembly and the elongate tubular member. The indicator apparatus may have indicator elements or formations, reference signs or other indicia configured to indicate the adjustment of the gas outlet assembly, for example a level of gas flow regulation provided by the gas outlet assembly. The indicator elements may be arranged to indicate and correlate broadly with variable levels of gas flow regulation. At least one of the indicator elements may be provided on one of the first and second members, while a distinct other of the indicator elements is provided on the other of the first and second members. At least one of the indicator elements may be provided on a gauge body separate from the turning body, while at least one distinct other of the indicator elements is provided on the turning body.

[0024] The adjustable nozzle assembly may include a fastening means to secure the nozzle outlet at desired internal dimensions.

[0025] The adjustable nozzle assembly may include a built-in flow valve for adjustment of air volume for intake and output.

[0026] The hollow elongate tubular member may be configured to allow passage of air.

[0027] The fire blower apparatus may be configured to focus or direct the flow of expelled air to an oxygen-starved region of a fire.

[0028] In certain embodiments of the disclosed technology the gas flow restriction mechanism may comprise a dial valve, iris mechanism or aperture ring.

[0029] The elongate tubular member of the apparatus may comprise first and second lengths configured to be angularly adjustable relative to each other.

[0030] The adjustable nozzle assembly may comprise fire retardant materials.

[0031] The mouthpiece may comprise a heat insulated material.

[0032] The first and second members of the nozzle assembly may be configured and / or sized such that tolerance or spacing between the first member and the second member, when they are in closest engagement assembled to each other, does not exceed about 0.75 mm in any region. The configuration and / or sizing of the two members may be such that the tolerance or spacing between them nowhere exceeds about 0.05 mm.

[0033] At least some components of the adjustable nozzle assembly may be annealed, that is, their structure may have been previously modified by prior heat treatment during manufacturing or assembly.

[0034] According to a further aspect of the disclosure there is provided a method of manufacturing the disclosed fire blower apparatus, the method including subjecting at least one of the first and second members of the nozzle assembly to a heating step. The heating step may comprise annealing the at least one member.

[0035] The manufacturing method may include preselecting configurations and / or dimensions of the first and second members such that, before the heating step is carried out, at least some of the cooperating indicator elements of the indicator apparatus misalign with one another when the first and second members are assembled together. The configurations of the first and second members may be preselected such that at least two of the indicator elements are offset from each other before the heating step is carried out. The offset may be an angular offset. The angular offset of the indicator elements prior to the heating step may be in a range from about 10 degrees to about 20 degrees. The angular offset may be about 15 degrees ± 2 degrees when the first and second members are fully tightened against each other; for example, when the turning body seats flush against the gauge body prior to the heating step.

[0036] The heating step may comprise heating at least one of the first and second members of the nozzle assembly to a treatment temperature in a range from about 300eC to about 600eC. The heating step may comprise heating the at least one member to a treatment temperature in a range from about 400eC to about 500eC. The treatment temperature may be approximately 450eC ± 10eC, for example. Embodiments of the disclosed technology will now be described, by way of example only, with reference to the accompanying drawings.

[0037] BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In the drawings:

[0039] Figure 1 is top three-dimensional view of an exemplary embodiment of the disclosed fire blower apparatus;

[0040] Figure 2 is bottom three-dimensional view of the fire blower apparatus of Figure 1 ;

[0041] Figure 3 is a sectional top view of the fire blower apparatus of Figure 1 ;

[0042] Figure 4 is top three-dimensional broken view of the disclosed fire blower apparatus;

[0043] Figure 5 is bottom three-dimensional broken view of the fire blower apparatus of Figure

[0044] 4;

[0045] Figure 6 is top broken view of the fire blower apparatus of Figure 4;

[0046] Figure 7 is a sectional top broken view of the fire blower apparatus of Figure 4;

[0047] Figure 8 is a front view of the fire blower apparatus of Figure 4;

[0048] Figure 9 is a rear view of the fire blower apparatus of Figure 4;

[0049] Figure 10 is a front three-dimensional view of an exemplary gas outlet assembly of the fire blower apparatus, comprising an adjustable nozzle assembly;

[0050] Figure 11 is a rear three-dimensional view of the adjustable nozzle assembly of Figure 10;

[0051] Figure 12 is a top view of the adjustable nozzle assembly of Figure 8;

[0052] Figure 13 is a front view of the adjustable nozzle assembly of Figure 8; Figure 14 is an exploded view of the adjustable nozzle assembly of Figure 8;

[0053] Figure 15 is a cross-sectional view of the adjustable nozzle assembly of Figure 8;

[0054] Figure 16 is a side view of a further exemplary embodiment of an adjustable nozzle assembly having a simplified construction, wherein an internal body is integrated with a gauge body to form a single-piece first member, and wherein an outer, cooperating second member is provided by a rotatable turning body configured to receive the internal body of the first member;

[0055] Figure 17 is a three-dimensional view of the embodiment of the nozzle assembly of Figure 16;

[0056] Figure 18 is a three-dimensional view of the single-piece first member of the adjustable nozzle assembly of Figure 16, showing how the internal body is integrated with the gauge body;

[0057] Figure 19 is a side view of the single-piece first member of Figure 18;

[0058] Figure 20 is a front view of the embodiment of the adjustable nozzle assembly of Figure

[0059] 16;

[0060] Figure 21 is a partial side view of a second exemplary embodiment of the disclosed fire blower apparatus which includes the adjustable nozzle assembly of Figure 16;

[0061] Figure 22 is a partial three-dimensional view of the embodiment of the fire blower apparatus of Figure 21 shown in a partially open condition;

[0062] Figure 23 is a side view of the rotatable turning body or second member of the adjustable nozzle assembly shown in Figures 16 and 17;

[0063] Figure 24 is a front view of the embodiment of the turning body or second member of Figure 23;

[0064] Figure 25 is a three-dimensional view of an upstream gas inlet port or mouthpiece of the disclosed fire blower apparatus; Figure 26 is a three-dimensional bottom view of the mouthpiece of Figure 25;

[0065] Figure 27 is a front view of the mouthpiece of Figure 25;

[0066] Figure 28 is a rear view of the mouthpiece of Figure 25;

[0067] Figure 29 is a side view of the mouthpiece of Figure 25; and

[0068] Figure 30 is a section view from the side of the mouthpiece of Figure 25.

[0069] DETAILED DESCRIPTION WITH REFERENCE TO THE DRAWINGS

[0070] An exemplary embodiment of a fire blower apparatus is described below. The fire blower apparatus finds particular application in promoting combustion of a fire by delivering oxygencontaining gas to a burning fuel (or combustible material) or fire, in particular the fire blower apparatus may be configured to permit a user to focus or direct a flow of expelled air to an oxygen- starved region of a fire. However, the fire blower apparatus may be suitable for numerous other applications, including, for example, extinguishing a flame, e.g. blowing out a candle; moving small objects through air pressure such as directing a high velocity stream of air towards a surface to remove debris; providing a controlled stream of air to obtain a controlled result; blowing other gases, liquids or solids through the apparatus; or sucking gases, liquids or solids through the apparatus. Furthermore, the fire blower apparatus may be used to reduce smoke generation or increase fuel burning efficiency.

[0071] Referring to the drawings, an embodiment (100) of the disclosed fire blower apparatus comprises at least one elongate tubular member (101 ) having an inlet port (102) positioned at an upstream end thereof for receiving an oxygen-containing gas, and an adjustable gas outlet assembly (103) positioned at a downstream end thereof for regulating gas flow through a nozzle (104). The gas outlet assembly (103) may comprise a nozzle assembly.

[0072] The hollow elongate tubular member (101 ) is configured to allow passage of an oxygen-containing gas such as air. However, the hollow elongate tubular member (101 ) may also permit the passage of other gases, liquid and solids as a user may require.

[0073] The fire blower apparatus (100) is shown as a whole in Figures 1 to 3, and with break lines in Figures 4 to 7. The fire blower apparatus (100) is of a length that is suitable to allow a user to gain close proximity to the oxygen-starved central region of a fire with the nozzle (104) and adjustable gas outlet assembly (103), whilst the user remains at a distance from the fire and contacts the inlet port (102).

[0074] The fire blower apparatus (100) may include a handle formation (1 13). The handle formation (1 13) may cover a portion of the elongate tubular member (101 ) and may be made of a heat resistant material such that an area of high thermal resistance is provided which allows a user to hold onto the elongate tubular member (101 ), which may have warmed during use in close proximity to a fire or open flame. Thus, the handle formation (113) may reduce the likelihood of burns or injury as the elongate tubular member (101 ) conducts heat from the fire.

[0075] The fire blower apparatus (100) is configured to permit adjustment of one or more parameters independently selected from the group consisting of: a volume of air passing through the nozzle (104) for a given pressure of said volume of air applied at the inlet port; a velocity of the air passing through the nozzle (104); an exit angle of air emerging from the nozzle (104); and a shape or pattern of a volume of air emerging from the nozzle (104). The shape or pattern may range from a spread-out or scattered shape, for example a conical shape, to a narrow jet for pinpoint delivery of the air to a fire or a part of a fire. The adjustment of one or more of these parameters will allow a user to control and accurately provide air, necessary to facilitate successful and efficient combustion, to an oxygen-starved central region of a fire. Thus, by controlling the volume, velocity, angle, shape or pattern of air to a fire, the fire blower apparatus can inhibit smothering.

[0076] The upstream gas inlet port (102) may comprise a mouthpiece. The mouthpiece may be funnel shaped or cone-like, as illustrated in Figures 1 to 7, or cylindrical. The mouthpiece may further be shallow or deep. The mouthpiece may consist of a heat insulated material. The advantage of constructing the mouthpiece of a heat insulated material may be that it lowers the risk of injury through burning to a user.

[0077] In some embodiments, as shown in Figures 25 to 30, the mouthpiece (102) may have an initial tapered shape at a portion of the mouthpiece distal to the position at which it engages with the elongate tubular member (101 ). Its shape may then narrow towards a cylindrically shaped portion at a portion of the mouthpiece proximal to the position at which it engages with the elongate tubular member (101 ). The mouthpiece may further include a circumferential edge or lip at the most distal portion of the mouthpiece relative to the elongate tubular member (101 ). The lip may be such that a user may press their mouth against the mouthpiece when blowing on the apparatus (100). In some embodiments, the mouthpiece body may have a more angular conical shape and in other embodiments the mouthpiece body may have a more curved conical shape at the distal portion of the mouthpiece relative to the elongate tubular member (101 ).

[0078] The mouthpiece may include a step on an internal surface thereof, as shown in Figure 30, to abut the elongate tubular member (101 ) when the apparatus is assembled.

[0079] The oxygen-containing gas received at the upstream end via the inlet port (101 ) may be air. The oxygen-containing gas enters the fire blower apparatus (100) from a user’s mouth blowing into the mouthpiece. In other embodiments of the disclosed technology (not shown) the mouthpiece may be omitted and a bellows, compressor, or other suitable air delivery device may be connected to the inlet port (101 ) to provide a flow of air through the fire blower apparatus.

[0080] A user may blow into the fire blower apparatus (100) via the mouthpiece (102) to allow air to pass though the elongate tubular member (101 ) towards the adjustable gas outlet assembly (103), and the air may exit the fire blower apparatus (100) through the nozzle (104) directly into a fire or onto an oxygen-starved region of a fire. The consequence of the user blowing on the fire using the apparatus is an increased provision of oxygen to the region, causing an increased rate of combustion.

[0081] The adjustable gas outlet assembly (103) may be configured to permit independent adjustment of one or more of the parameters mentioned above, such as the volume or velocity of the air passing through the nozzle for a given pressure of said volume of air applied at the inlet port. The gas outlet assembly (103) may further be configured to permit tool-free manual adjustment of the parameters. In certain embodiments it may be arranged to permit adjustment to the bore shape and internal volume of the gas outlet assembly (103). It may be arranged to permit adjustment of the bore shape in a range from a straight bore nozzle for a tight pattern of emergent air for delivery to small areas, to a venturi bore nozzle for a wider pattern of emergent air for delivery to larger areas. A straight bore nozzle with a tight pattern of emergent air may be ideal for delivery of air to small areas such as, for example, a flame of a candle, removing debris or small particulates from a smaller surface, or providing oxygen to a very small area of a fire or oxygen -starved region of a fire. A venturi bore nozzle may be suitable for a wider pattern of emergent air for delivery to larger regions.

[0082] The adjustable gas outlet assembly (103) may comprise an adjustable nozzle assembly, which may further comprise an adjustable gas flow restriction mechanism. As best seen in Figure 7, the adjustable nozzle assembly (103) may comprise a first member (105) and a second member (106) configured to be movable relative to the first member (105). The nozzle assembly may further comprise a nozzle inlet (107) configured to receive air from the elongate tubular member (101 ), and a nozzle outlet (108) configured to expel air. At least one of the first and second members (105; 106) may be configured to serve as an internal body (discussed further below), and may further comprise an obstructing means (109) such as a pin formation configured at least partially to obstruct the nozzle outlet (108) when the first and second members (105; 106) are displaced relatively to each other. The above components make up the gas flow restriction mechanism.

[0083] The pin formation or other obstructing means (109) may be integral with or connected to one of the first and second members (105; 106). As discussed further below, in some configurations, the pin formation (109) may extend from or be integrated with the internal body. If these two components are integrated with each other to form a unibody construction, the construction may be referred to as a floating pin.

[0084] The pin formation (109) and internal body may be fixed with respect to the elongate tubular main body (101 ).

[0085] In the drawings, the pin formation (109) is shown configured to adjust the internal dimensions and shape of the nozzle outlet (108). Adjustment of the internal dimensions of the nozzle outlet (108) permits adjustment of one or more parameters independently selected from the group consisting of: a volume of air passing through the nozzle outlet (108) for a given pressure of said volume of air applied at the nozzle inlet (107); a velocity of the air passing through the nozzle outlet (108); an exit angle of air emerging from the nozzle outlet (108); and a shape or pattern of a volume of air emerging from the nozzle outlet (108). These adjustments to one or more of the parameters described allow a user to control the air stream expelled from the nozzle (104) or nozzle outlet (108) of the fire blower apparatus (100). The air can be directed to where it is needed and in a volume and at a velocity controlled by the user, to promote combustion.

[0086] Figure 8 shows a front view of the exemplary embodiment of the fire blower apparatus (100) in a closed condition with the pin formation (109) shown projecting from the centre. The obstructing means is completely extended into the nozzle outlet (108) of the second member (106) of the adjustable nozzle assembly (103) to close the aperture and prevent air from being expelled from the nozzle. The adjustable nozzle assembly (103) is shown surrounded by the handle formation Figure 9 shows a rear view of the fire blower apparatus (100) inlet port, comprising a mouthpiece extending from the elongate tubular member (101 ).

[0087] As illustrated in Figures 10 to 15, the adjustable nozzle assembly (103) may define an inlet aperture and an outlet aperture of reduced cross-sectional area relative to that of the inlet aperture. The inlet aperture may be located at the nozzle inlet (107) and the outlet aperture may be located at the nozzle outlet (108). The reduced cross-sectional area of the outlet aperture of the adjustable nozzle assembly (103) relative to the inlet aperture may, in use, create a venturi effect resulting in an increased velocity of the air expelled through the nozzle outlet (108).

[0088] In certain embodiments of the disclosed technology, the location, configuration, construction, sizing and shapes of the component parts, inner cavities, inlets and apertures of the adjustable nozzle assembly (103) - in particular the location, configuration, shapes and dimensions of the nozzle outlet (108), the first and second members (105; 106), the pin formation (109) and floating pin structure, and the mouthpiece (102) - may function to provide a non-return or one-way valve during use, or may facilitate a one-way flow of air via the apparatus (100), thereby obviating the requirement for a separate mechanical non-return or one-way valve to prevent a user from inhaling smoke or heated air when taking a breath before proceeding to blow into the apparatus (100). For example, when using the apparatus to blow onto or into a fire, the shapes, configurations, sizing and locations of the cooperating components of the adjustable nozzle assembly (103) may be sufficient to inhibit or prevent a user from inhaling smoke when taking a breath of fresh air between each blow into the apparatus (100).

[0089] Alternatively, or in addition, in some embodiments of the disclosed technology the adjustable nozzle assembly (103) - or another suitable part of the fire blower apparatus 100 - may include a non-return or one-way valve (not shown) to inhibit or prevent the user from inhaling smoke or heated air through the nozzle outlet (108) during use.

[0090] In other words after blowing and passing air from the inlet port (102) via the elongate tubular member (101 ) out of the nozzle outlet (108) via the nozzle inlet (107), the user may need to take a breath before commencing blowing on the apparatus (100). During this time, when a user is required to take another breath before continuing to blow onto the apparatus, the user may take said breath near and partially through the apparatus (100) with limited to no inhalation of smoke or heated air. When inhaling near the apparatus, air is prevented from entering the nozzle outlet (108) and passing through the nozzle inlet (107) into a user’s mouth and lungs via the mouthpiece

[0091] (102) by the construction and arrangement of the components of the adjustable nozzle assembly

[0092] (103) and / or by a non-return or one-way valve, therefore inhibiting or preventing a user from accidentally inhaling smoke or heated air via the apparatus.

[0093] The nozzle outlet (108) may be tapered, defining an internal cavity shaped to receive the tip of the complementary pin formation (109) configured to nest flush with an internal wall of the nozzle outlet (108) when the pin formation is advanced to an extended position. The nozzle outlet (108) may define a frustoconical internal wall having a wall angle in a range from about 20eto about 75erelative to a principal axis of the nozzle assembly (104). The wall angle may be in a range from about 40eto about 50edegrees relative to the principal axis. The wall angle may be approximately 45erelative to the principal axis.

[0094] The first and second members (105; 106) of the nozzle assembly (103) may comprise complementarily threaded or screwed components, as illustrated in Figures 14, 18 and 19. The components may be configured to define a plenum (1 10), as illustrated in Figures 7, 15 and 20, for receiving and constricting gas flow received into the nozzle assembly (103). At least one of the first and second members (105; 106) may comprise a turning body. The pitch of the thread of the turning body may be configured so that a full rotation of the turning body provides a range of adjustments from a closed condition to a fully open condition of the adjustable nozzle assembly (103). The adjustable nozzle assembly (103) may be configured such that displacement of the first and second members (105; 106) relatively to each other is obtained by rotation (e.g. by means of the cooperating screwed formations), telescoping, or sliding of one of the members relatively to the other.

[0095] As shown in Figures 14, 18 and 19, one of the first and second members of the adjustable nozzle assembly (103) may provide an internal body (105) or nozzle base which is attached, to or integrated with, the pin formation (109). As noted, if the internal body and pin formation are integrated with each other, this arrangement may be referred to as a floating pin. Figures 10 to 22 show exemplary embodiments of the adjustable nozzle assembly including the floating pin.

[0096] As noted, in certain embodiments of the disclosed technology the floating pin construction may be effective to inhibit inhalation of smoke through the nozzle outlet (108) by acting as a one-way or non-return flow mechanism.

[0097] In the exemplary embodiments shown in Figure 14, the floating pin may be configured to advance into or reverse out of the nozzle outlet (108) upon rotation of the second member or turning body (106) relative to the first or internal member (105). The screwing displacement or sliding action of the floating pin acts to obstruct the nozzle outlet (108), and the obstruction causes adjustment of one or more parameters independently selected from the group consisting of: a volume of air passing through the nozzle outlet (108) for a given pressure of said volume of air applied at the nozzle inlet (107); a velocity of the air passing through the nozzle outlet (108); an exit angle of air emerging from the nozzle outlet (108); and a shape or pattern of a volume of air emerging from the nozzle outlet (108).

[0098] The described configuration of the nozzle assembly (103) is such that, in the case of some embodiments, only a small volume of air needs to be blown into the mouthpiece of the apparatus (100) to cause a fast jet of air to emerge from the nozzle outlet (108) that is highly effective at promoting combustion of a fire. This can be more convenient for a user and typically does not require uncomfortable exertion such as might be experienced if blowing directly into a fire, for example. Moreover, the user’s face is removed from proximity to the fire, lowering his or her risk of discomfort or burning caused by the heat of the fire.

[0099] It will be noted that the internal body (105) of the depicted embodiment defines an annular groove to receive an O-ring to serve as a seal for inhibiting pressure losses.

[0100] The adjustable nozzle assembly may include an indicator apparatus. This may define or include indicator elements or formations (1 11 ; 112) configured to indicate the relative adjustment of the gas outlet assembly, for example its internal dimensions or the level of gas flow regulation. The indicator elements may be arranged such that, when acting in combination with one another, they serve to provide a gauge assembly.

[0101] The indicator apparatus (1 11 ; 1 12) may comprise one or more indicator elements (1 12) located on a surface of one of the first and second members (105; 106), e.g. at, on, in or extending from the first member or internal body (105). For example, the indicator element may be provided on a gauge body or nut body (1 14) integrated with the internal body (105), as shown in Figures 18 and 19. Instead, the indicator element may be provided on the elongate tubular member (101 ). The indicator apparatus may further comprise one or more cooperating indicator elements (11 1 ) located on a surface of the other one of the first and second members (105; 106), e.g. on the turning body. Thus, indicator elements may be provided on sides of the turning body and, when aligned with one or more other indicator formation fixed relative to the tubular member, may indicate generally a relative level of constriction or opening of the nozzle.

[0102] The indicator apparatus (11 1 ; 1 12) may show to a user to what extent the nozzle outlet (108) is unobstructed or the apparatus (100) is open based on the adjustment made to the adjustable nozzle assembly (103), for example that the nozzle is fully open, wherein the pin formation (109) is the furthest retracted from the nozzle outlet (108), partially open wherein the pin formation (109) is partially retracted from the nozzle outlet (108), or in a closed condition wherein the pin formation (109) is seated flush with the nozzle outlet (108).

[0103] An example embodiment of an indicator apparatus is shown in Figures 4 to 7, wherein a reference indicator (112) is shown as a pointer, arrow or triangular formation provided on a gauge formation, and additional indicator elements (1 11 ) are shown as lines of varying numbers of dots marked on or engraved into the surface of the turning body of the adjustable gas outlet assembly (103).

[0104] In some embodiments, as shown in Figures 16 and 17, the reference indicator (112) may be provided on a gauge body or nut body (1 14) which may be integrally formed with or extending from the internal body (105) to form the first member. Alternatively, or in addition, the additional indicator elements (1 11 ) may include a reference sign (115), such as a word mark or textual matter or the like, as shown in Figure 16, for example. This may be aligned with the arrow or other reference indicator (112) during assembly of the apparatus (100), so that the gauge body (1 14) and the turning body (106) are seated flush against each other in a starting condition of the nozzle assembly. The tolerance or spacing between the turning body and gauge body may be as little as 0.05 mm, for example, when the turning body is fully tightened up against the gauge body. A method of obtaining this close tolerance is explained elsewhere in this document.

[0105] During use of the fire blower apparatus (100), alignment of the arrow or other indicator (112) with any one of the levels of adjustment indications (111 ), which may include the reference sign (115) as shown in Figure 16, for example, shows a user at what relative level of adjustment the internal dimensions of the nozzle (104) are, or how far the floating pin is advanced into the outlet aperture or retracted from it. In certain alternative embodiments (not shown), indicator elements may be provided directly on the elongate tubular member (101 ). The indicator elements may comprise a series of lines, colours or other suitable indication means to indicate to a user the level of adjustment of the internal dimensions of the nozzle (104). In an exemplary embodiment shown in Figure 14, the level of adjustment indications (1 11 ) are shown on the second member (106), that is the turning body, and rotation of the turning body relative to the first member (105), which may be connected to the elongate tubular member (not shown), adjusts the internal dimensions of the nozzle outlet (108) as the obstructing means (109), that is the floating pin, slides in and out of the nozzle outlet. In some embodiments of the disclosed technology, the reference sign (1 15) may be the word mark “DONKEY”. In some embodiments, an alignment of the arrow (1 12) with this word mark may denote a fully closed condition of the fire blower apparatus (100), or a condition in which the flow of air is most restricted; however, it will be appreciated that alignment of the arrow and mark may also be used to indicate other conditions of adjustment of the apparatus (100). Following initial assembly of the apparatus (100), the reference sign (1 15) may be aligned with the reference indicator (1 12). This may indicate correct alignment of the components of the apparatus (100) to a manufacturer of the apparatus (100).

[0106] In embodiments which include a gauge body or nut body (114) integrally formed with or extending from the first member or internal body or nozzle base (105), forming a single integrally formed component of the adjustable nozzle assembly (103), extreme precision may be required when machining and fitting the components to one another, to ensure the reference sign (115) accurately aligns or lines up with the reference indicator (112) when the first and second members (105; 106) are screwed together and two parts seated against one another. During manufacturing, such as by way of Computer Numerical Control (CNC) machining or the like, tolerances of about 0.05 mm may be specified to overcome errors in machining. For example, to ensure the word mark “DONKEY” as shown in the embodiment in Figures 16 and 21 aligns with the arrow, a tolerance of about 0.05 mm may be used when machining the components of the apparatus.

[0107] Furthermore, during manufacturing of the apparatus, the configuration of components such as the first and second member may be preselected such that the reference sign (1 15) and the reference indicator (1 12) initially do not line up with each other. Additional measures may then be taken to ensure a correct, accurate or precise alignment of the apparatus components and indicator elements when the nozzle assembly is in its final condition ready for sale and use. As part of the process to assemble the components and / or the apparatus, such additional measures may include heat treating the apparatus or one or more of its components at specific temperatures, which in some cases may result in annealing. This annealing may cause one or more of the components to expand or contract in size. Heat treatment may be done in any suitable way, such as with an open flame, by induction or in an oven such that the temperature may be precisely controlled. Failure to properly anneal the components or the apparatus may result in the apparatus and / or its components naturally annealing, expanding or contracting, in an unregulated or uncontrolled manner, either inherently or when being used by end consumers to blow air into hot fires. It is important to precisely control the annealing temperature, timing and cooling conditions to achieve the desired effect and manufacturing. In certain modes of manufacturing the disclosed nozzle body, the annealing temperature may range from about 300°C to about 600°C.

[0108] In example embodiments, the application of these additional measures such as heat processing or heat treating may then be used to "correct" the initial 15 degree offset (if present from initial machining or assembly) and ensure that the arrow or reference indicator (112) and the reference sign (115) reliably and accurately line up with each other upon final assembly, that is, to permit the indicator and sign to be “zeroed in” on each other in the final product. These measures may also ensure that the first and second members (105; 106) of the nozzle assembly (103) remain reliably aligned with each other during subsequent use, even after encountering hot environments or hot fires during their lifetime which otherwise might have caused random annealing or deformations of the brass or other material of the components, resulting in undesirable misalignment of the apparatus components, such as misalignment of the arrow or reference indicator (112) and the reference sign (115) of the indicator apparatus or gauge body.

[0109] Therefore, according to a further aspect of the disclosure there is provided a method of manufacturing the disclosed fire blower apparatus wherein at least one of the first and second members of the nozzle assembly is subjected to a heating step. The heating step may comprise annealing the at least one member.

[0110] The manufacturing method may include preselecting configurations and / or dimensions of the first and second members such that, before the heating step is carried out, at least some of the cooperating indicator elements of the indicator apparatus misalign with one another when the first and second members are assembled together. The configurations of the first and second members may be preselected such that at least two of the indicator elements are angularly offset from each other before the heating step is carried out. The angular offset of the indicator elements prior to the heating step may be in a range from about 10 degrees to about 20 degrees. The angular offset may be about 15 degrees ± 2 degrees when the first and second members are fully tightened against each other, that is, when the gauge body is seated flush against the turning body prior to the heating step.

[0111] The heating step may comprise heating at least one of the first and second members of the nozzle assembly to a treatment temperature in a range from about 300eC to about 600eC. The heating step may comprise heating the at least one member to a treatment temperature in a range from about 400eC to about 500eC. The treatment temperature may be approximately 450eC ± 10eC, for example.

[0112] At least some of the various components of the fire blower apparatus may be made from or include brass or other metallic materials. Such materials may be subject to the effects of heating or heat treatment which may cause the material to expand or contract during manufacturing or use.

[0113] In other embodiments, at least some components of the adjustable nozzle assembly and other part of the apparatus may comprise fire retardant materials. The adjustable nozzle assembly may further include a fastening or catch means to set and maintain the dimensions of the nozzle outlet at a desired adjustment. The catch means may, for example, include a spring-urged ball detent mechanism.

[0114] In certain embodiments (not shown) of the disclosed technology the gas flow restriction mechanism need not be limited to the assembly or mechanism described above and may comprise a dial valve, iris mechanism or aperture ring. The iris mechanism may comprise a base plate, blades, and blade actuating ring. In such embodiments, displacement of the blades relative to the blade actuating ring and base plates may adjust the internal dimensions of the nozzle. The iris mechanism may act similarly to the mechanism used in a camera to control the amount of light entering the lens, however instead of controlling the stream of light, an iris mechanism used in the fire blower apparatus may control the stream of air expelled from the nozzle of the apparatus.

[0115] Although not shown in the drawings, the elongate tubular member (101 ) of the apparatus may comprise first and second lengths configured to be angularly adjustable relatively to each other. The angular adjustment of the first and second lengths of the elongate tubular member may permit a user to direct a flow of air expelled from the nozzle to an area that may be hard to reach with a full length of the elongate tubular member, by, for example, allowing the user to control airflow around obstructions in a fire.

[0116] The foregoing description has been presented for the purpose of illustration; it is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Persons skilled in the relevant art can appreciate that many modifications and variations are possible in light of the above disclosure.

[0117] The language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter. It is therefore intended that the scope of the disclosed technology be limited not by this detailed description, but rather by any claims that issue on an application based hereon. Accordingly, the disclosure of the embodiments of the technology is intended to be illustrative, but not limiting, of the scope of the technology to be set forth in any accompanying claims.

[0118] Finally, throughout the specification and any accompanying claims, unless the context requires otherwise: • the word ‘comprise’ or variations such as ‘comprises’ or ‘comprising’ will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers;

[0119] • the word ‘fire’ used in reference to a component susceptible to combustion will be understood in its broadest sense and will, without limitation, encompass reference to flames, combustion, combustion reaction, burning coals or charcoal, embers, combustible fuels, fuel, wood, paper and other combustible materials or components; and

[0120] • the phrase ‘combustion centre’ used in reference to the centres of a fire or combustion reaction in which heat is concentrated, will be understood in its broadest sense and will, without limitation, encompass reference to regions of combustion, centres of combustion, oxygen-starved combustion centres, oxygen -starved central regions or central regions of a combustion reaction.

Claims

CLAIMS:1 . A fire blower apparatus for promoting combustion of a fire, the apparatus comprising at least one hollow elongate tubular member having an inlet port comprising a mouthpiece positioned proximate an upstream end thereof for receiving an oxygen-containing gas, and an adjustable gas outlet assembly comprising an adjustable nozzle assembly positioned proximate a downstream end thereof and configured to regulate gas flow through the gas outlet assembly; wherein the nozzle assembly comprises a nozzle and an adjustable gas flow restriction mechanism configured to restrict the oxygen-containing gas from passing through the nozzle.

2. The fire blower apparatus as claimed in claim 1 , wherein the adjustable nozzle assembly is arranged to provide adjustment of either or both a variable bore shape and an internal volume of the nozzle.

3. The fire blower apparatus as claimed in claim 1 or claim 2, wherein the adjustable gas flow restriction mechanism comprises: a first member and a second member configured to be movable relative to the first member; a nozzle inlet configured to receive air from the elongate tubular member, and a nozzle outlet configured to expel air; and wherein at least one of the first and second members comprises an obstructing means configured at least partially to obstruct the nozzle outlet when the first and second members are displaced relatively to each other.

4. The fire blower apparatus as claimed in claim 3, wherein the obstructing means is fixed with respect to the elongate tubular main body.

5. The fire blower apparatus as claimed in claim 3 or claim 4, wherein the nozzle outlet is tapered and defines an internal cavity shaped to receive the obstructing means, the nozzle outlet further defining a frustoconical internal wall having a wall angle in a range from about 20eto about 75erelative to a principal axis of the nozzle assembly.

6. The fire blower apparatus as claimed in any one of claims 3 to 5, wherein at least one of the first and second members of the nozzle assembly comprises an internal body attached to or integrated with a pin formation.

7. The fire blower apparatus as claimed in claim 6, wherein the internal body and pin formation are of unibody construction.

8. The fire blower apparatus as claimed in any one of claims 3 to 7, wherein the first and second members comprise complementarily threaded components, and at least one of the first and second members comprises a turning body and the pitch of the thread is configured to provide that one full rotation of the turning body shall cause the adjustable nozzle assembly to be adjusted from a fully closed condition to a fully open condition.

9. The fire blower apparatus as claimed in any one of claims 3 to 8, which includes an indicator apparatus having indicator elements configured to indicate the adjustment of the gas outlet assembly, and wherein the indicator elements correlate to a level of gas flow regulation by the nozzle assembly.

10. The fire blower apparatus as claimed in claim 9, wherein at least one of the indicator elements is provided on one of the first and second members, while a distinct other of the indicator elements is provided on the other of the first and second members.1 1 . The fire blower apparatus as claimed in any one of claims 3 to 10, wherein at least some components of the adjustable nozzle assembly are annealed.

12. The fire blower apparatus as claimed in any one of claims 3 to 11 , wherein the first and second members of the nozzle assembly are configured such that spacing between the first member and the second member, when they are in closest engagement assembled to each other, does not exceed about 0.75 mm in any region.

13. The fire blower apparatus as claimed in any one of claims 3 to 12, wherein the adjustable nozzle assembly is configured to permit adjustment of one or more parameters independently selected from the group consisting of: a volume of air passing through the nozzle for a given pressure of said volume of air applied at the inlet port; a velocity of the air passing through the nozzle; an exit angle of air emerging from the nozzle; and a shape of a volume of air emerging from the nozzle ranging from a conical shape to a narrow jet of reduced diameter.

14. The fire blower apparatus as claimed in claim 13, wherein the adjustable nozzle assembly is configured to permit tool-free manual adjustment of any one or more of said parameters.

15. A method of manufacturing the fire blower apparatus as claimed in any one of claims 3 to 14, the method including subjecting at least one of the first and second members of thenozzle assembly to a heating step.

16. The method as claimed in claim 15, insofar as it is dependent on claims 9 and 10, which includes preselecting configurations of the first and second members such that, before the heating step is carried out, at least some of the cooperating indicator elements of the indicator apparatus misalign with one another when the first and second members are assembled together and fully tightened against each other.

17. The method as claimed in claim 15 or claim 16, wherein the heating step comprises heating at least one of the first and second members of the nozzle assembly to a treatment temperature in a range of approximately 450eC ± 10eC.

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