GAS HELPER ASSEMBLY AND BURNER NOZZLE

Abstract: A gas helper comprises a flame port portion (20), a reservoir portion (10) including a tapered nozzle (11) which is raised and lowered to operate the reservoir valve, a flame port tube (32) extending from the tapered nozzle to the flame port at the remote end of the flame port portion (20), and connection means coupled to the flame port tube (32) comprising a tubular coupling element (31) of flexible and resilient material to expandingly engage the nozzle (11). Anchoring means (30) are provided through which the end of the flame port tube (32) passes and against which the end of the coupling element (31) abuts. The anchoring means (30) comprises a fork element (34), and a further fork element (35) supporting the central region of the coupling element. In a modified form, the nozzle head is moved in the reverse direction to open the valve.

Description: Gas Helper Assembly and Burner Nozzle The present invention relates to gas helpers, and in particular to the connection of the constituent elements. A conventional gas helper has a reservoir to contain the gas, and a flame port where gas from this reservoir is released, mixed with air, ignited, and burnt. The connection between the two is usually achieved by linking a nozzle from a valve mounted upon the reservoir to the flame port by a flame port tube, the flame port ideally being situated at the end of a tubular member so the user may operate the gas helper whilst their hand remains a safe distance from the flame port. It is advantageous to be able to manufacture separately the reservoir portion (body portion) which is generally made of plastic and is held by the user, and the flame port portion (rod portion), which is preferably made out of metal because it will be positioned in close proximity to a flame. The body and rod portions being united relatively late in the manufacturing process. The means of connecting the reservoir nozzle to the flame port portion must be suitable for this method of production. A conventional burner nozzle, as illustrated for example in Tokai, US 5 697 775, incorporates a spring loaded valve, which is opened when the nozzle is raised from the reservoir and is closed when the nozzle lowered. In a device such as a gas helper, the raising of the nozzle is usually achieved by a pivoted lever, so that as one end of the lever is depressed, the other end raises the nozzle. When the nozzle is released, the nozzle falls back under the influence of a spring, closing the valve. The preferred method of igniting the gas is by means a spark at the flame port, caused by the compression of a piezo-electric. However, the length of the flame port portion means that gas released from the reservoir is delayed whilst it displaces the volume of air within the tube through that portion. The gas therefore has to be released from the reservoir in time to reach the flame port by the time the spark is produced. Tokai, EP 0 515 693 discloses a gas helper in which the flame port portion and the reservoir portion are manufactured separately and then joined together. The reservoir nozzle ends in an annular pad of packing material, which abuts a rigid structure leading to the flame port upon the flame port portion being united with the reservoir portion. The valve is operated by a lever which raises the nozzle from the reservoir to open the valve, and allowing the nozzle to fall back under the influence of a spring to close the valve when the lever is released. When the nozzle is so raised, the packing material is compressed against the rigid structure, and when the nozzle falls the material must spring back to preserve the seal. The components must be made to a close tolerance if an effective seal between the packing material and the rigid structure is to be maintained. One object of the present invention is to provide a gas helper in which the assembly and operation processes are facilitated. According to one aspect of the invention there is provided gas helper comprising a flame port portion, a reservoir portion including a tapered nozzle which is raised and lowered to operate the reservoir valve, a flame port tube extending from the tapered nozzle to the flame port at the remote end of the flame port portion, and connection means coupled to the flame port tube comprising a tubular coupling element of flexible and resilient material to expandingly engage the nozzle, characterized by anchoring means through which the end of the flame port tube passes and against which the end of the coupling element abuts. In its preferred form, this provides a gas helper which is safer and which prevents leakage of the gas from the cartridge. A further object of the present invention is to provide a safe and efficient nozzle whose valve is opened by depression of the nozzle towards the gas reservoir. According to a second aspect of the invention there is provided a gas helper including a burner nozzle comprising a nozzle head, a resilient means, and a valve, such that when the nozzle head is depressed, the nozzle head opens the valve and deforms the resilient means so that upon releasing the nozzle head the resilient means closes the valve and returns the nozzle head to its original position. In a preferred form, the present gas helper includes a nozzle head, a resilient means, a plunger having a valve cap, a gasket, and supporting and constraining means such that when the nozzle head is depressed, the base of the nozzle head lowers the plunger so that an opening is formed between the plunger cap and the gasket, and deforms the resilient means, so that upon releasing the nozzle head the plunger is raised, in turn raising the nozzle head, and the plunger cap is pulled up against the gasket. When mounted upon a conventional gas reservoir, the burner nozzle provides an incorporated valve which is opened upon depression of the nozzle head and closes upon release. Operating means, such as a push button of a gas helper, may now be designed so that a conventional lever to reverse the direction of the operating action is no longer needed. A gas helper embodying the invention will now be described, by way of example, with reference to the drawings, in which: Fig. 1 is a general arrangement of the complete gas helper to which the invention relates; Fig. 2 shows the end of the flame port portion of the gas helper. Figs. 3A and 3B are simplified diagrammatic sections through the connection means in the unoperated and operated positions respectively; Figs. 4A and 4B are simplified diagrammatic sections through a further embodiment of the connection means in the unoperated and operated positions respectively; Figs. 5A and 5B are simplified diagrammatic sections through a further embodiment of the connection means in the unoperated and operated positions respectively; Fig. 6 is a simplified perspective view of the anchoring means; Fig. 7 is an enlarged section of an alternative form of gas nozzle and surrounding portions of the gas reservoir and the supporting and constraining means; and Fig. 8 is a section of an alternative embodiment of the gas nozzle, again including the surrounding portions of the gas reservoir and the supporting and constraining means. Referring to Fig. 1, the system comprises a handle portion 10, a flame port portion 20, and a connecting means 30, which together form the gas helper as shown in Fig. 1. The handle portion includes the ignition control mechanism and the gas reservoir 12. The reservoir nozzle 11 communicates with the gas reservoir 12 via a valve (not shown) which is opened by the raising of the reservoir nozzle by a lever (not shown) which in turn is operated by the operator, by a trigger upon the outside of the device for example. In more detail, the flame port portion 20 is made of metal and the cartridge or handle portion 10 is made of moulded plastic. A flame port 2 is arranged at the remote end of the flame port portion 20 and is fed with gas from a gas cartridge 12 by means of a gas tube 32. The gas helper is operated by pressing the operating button 8 which operates a lever (not shown) which pulls against the nozzle head 11 to open the valve and release the gas. Shortly thereafter the push button has compressed the piezo mechanism 7 to the extent that is necessary to create a spark and the gas is ignited at the flame port 2 at the remote end of the flame port part 4. Fig. 2 shows the end of the flame port portion 20, with the insulating tube 41, the spring burner element 44, the wire 42, which electrically connects an electrode of the piezo-electric element to the spring burner, and the flame port tube 32 are all connected to the wind protector 43, which in turn is connected to the metal casing 40. These elements are all broadly conventional, and may take many forms. The connecting means 30, shown in figs. 3A and 3B, comprise a tube 31 of flexible material and a connecting means or anchoring means 33. These two components together couple the reservoir nozzle 11 to the flame port tube 32, which leads to the end of the flame port portion 20. The reservoir nozzle 11 engages with the flexible tube 31. The conical narrowing of the nozzle assists this engagement, though the flexible tube could be flared instead or as well to similarly assist the engagement. The anchoring means 33 provides a means for connecting the two tubes hermetically, and for supporting the flexible tube. The flexible tube is made from a resilient material such as PVC, EVA or PP. The anchoring means 33 (shown in more detail in Fig. 6) comprises a first U shaped flange 34 at its top end as shown for gripping the flame port tube 32. The flexible tube 31 is made of uniform diameter and of material of uniform thickness. Its upper portion is generally arranged below the first flange 34, as shown. The flame port tube 32 passes through the inner flange 34 and fits inside the upper end of the flexible tube 31, expanding that tube slightly and forming a seal. The anchoring means 33 also comprises a second U shaped flange 35 at its lower end for gripping the tube 31. The anchoring means 33 is mounted rigidly in the housing of the reservoir portion 10 of the gas helper and preferably moulded as an integral part of the inside wall of the reservoir portion which is a moulded plastic part. The initial engagement of the nozzle 11 with the flexible tube 31 preferably causes this tube to expand slightly, as indicated in Fig. 3A. (In Figs. 3 and 4, only the reservoir nozzle 1 1 and part of the reservoir tank 12 of the reservoir portion are shown.) When the gas helper is operated, the nozzle 11 is raised. This causes the nozzle to insert itself further into the flexible tube, causing the tube to deform. In particular, the tube 31 will expand and flare out further as a result, the tube 31 being constrained at its upper end by the anchoring means 33. The tube 31 may slide relatively freely on the nozzle, so that its deformation consists primarily of such expansion; the tube 31 may however engage only partially slidingly, so that its end is also to some extent carried upwards by the nozzle and compressed, so that its wall thickness is increased slightly adjacent to the nozzle. The distortion of the tube 31 resulting from the upward movement of the nozzle 11 exerts a restoring force on the nozzle. Upon release of the lever, the tube 31 tends to force the nozzle back towards the reservoir, closing the valve. Further restoring springs may also be provided, of course. It will be seen that the degree of insertion, and so the length of the flexible tube, may be varied considerably without substantially affecting the efficiency of the seal between the nozzle and the flexible tube. In the embodiment of Fig. 3 A and 3B the nozzle is shown inserted into the tube for a substantial distance in the rest position of Fig. 3 A; but abutment of the tip of the nozzle against the extreme lower end of the tube, slight insertion sufficient to accommodate the tolerances of manufacture of the respective parts, in the rest position as shown in Fig. 4A, will also result in adequate sealing. When the top of the nozzle is inserted fully (Fig. 3 A), the flexible tube tends to stick to the nozzle and become compressed upon the nozzle rising, whereas when the nozzle is, in its initial state, only partially inserted (Fig. 4A) or even not inserted, the flexible tube is more likely to flare outwards when the nozzle is raised. A combination of these two actions will occur when the nozzle starts at a state somewhere between slight and full insertion, but at all times an effective seal is maintained. The length of the flexible tube need not therefore be made to such a high degree of tolerance as, for example, an annular ring of packing material attached to the nozzle. Figs. 4 A and 4B show corresponding positions of the nozzle 11 in the closed and open positions respectively. In this embodiment the nozzle 11 just makes sealing contact with the tube 31 rather than being completely inserted in it. This difference compared to the embodiment of Figs. 3 A and 3B, relates to the chosen method of assembly. In the embodiment of Figs. 4A and 4B, in a first step, the flame port tube 32 is fixed into its anchoring flange 34 and the tube 31 is already fixed thereon and fixed to its anchor 35. In a subsequent step the reservoir and the nozzle 11 attached thereto is fixed to the gas helper and the seal is made between the nozzle 11 and the tube 31. In the embodiment of Figs. 3 A and 3B, on the other hand, the method of assembly is different. In a first step, the tube 31 with the flame port tube 32 attached to it is attached to the nozzle 11 and the tube 31 and flame port tube 32 are secured in their respective anchoring means 34, 35 which are part of the reservoir housing portion. In a subsequent step the reservoir portion is then fitted to the flame port portion and the flame port tube 32 is inserted in the flame port portion. Figs. 5A and 5B show a further modified arrangement in which the nozzle is physically separated from the connection means when the gas valve is closed. (The operating lever for the gas valve is also shown.) As shown in Fig. 5B, this allows any residual gas in the flame port tube to escape and become dissipated when the operating button is released and the gas helper turned off. The flame port tube is of narrow diameter, to ensure that the speed of the gas flow through it is sufficient for the gas to reach the flame port in time to be ignited by the spark from the piezo-electric element. The flame port tube is shown as having an outside diameter matching the inside diameter of the flexible tube. This allows a particularly simple and effective coupling between these two tubes. However, if some other tube diameter relationship is desired, the connecting means 30 can readily be modified to provide separate couplings to the two tubes. Any desired diameter can therefore readily be used for the flame port tube. It will be seen that there is no reason that the flame port tube need be similarly resilient to the flexible tube, and it could indeed be rigid, or it could be formed in a single element together with the junction box. Alternatively, the entire connecting means could be formed from a single element formed from resilient material, in which case an anchoring means as such would not be necessary, but the upward movement of the flexible portion must be suitably constrained against the upward movement of the reservoir nozzle. Fig. 7 shows an enlarged section of an alternative form of gas nozzle, which connects with tube 32, and surrounding portions of the gas reservoir and the supporting and constraining means. This alternative form of gas nozzle would be used in place of the nozzle arrangements described above (Figs. 3 to 5). Referring to Fig. 7, the gas nozzle comprises a nozzle head 50, a nozzle spring 52, a plunger 60 having a valve cap, a plunger spring 62, a gasket 66, a supporting member 56, and a constraining member 54. The nozzle head 50 incorporates a flange 68 by which it may be operated. The nozzle head 50 sits on a constraining member 54. This, and the supporting member 56, couple the nozzle head 50 securely to the gas reservoir 64, ensuring that the nozzle can only move upwards and downwards by predetermined distances. A nozzle spring 52 is coiled around the nozzle head 50, between the flange 68 at the top and the supporting means 56 at the bottom. An O-ring 58 is included between the constraining member 54 and nozzle head 50 to ensure an effective seal. The plunger 60 is located mostly within the constraining member 64. The shaft of the plunger 60 has three diameters. It is thickest at its top where it abuts the base of the nozzle head 50, and this diameter is substantially the same as that of the internal cavity of the constraining member 54 in which the plunger 60 is contained. This widest portion of the plunger 60 constrains a spring 58 which is coiled around the shaft of the plunger 60 and constrained at its opposite end by the constraining member 54. It does however allow gas around it. Alternatively this can be achieved or aided by cutting out a portion of the full circumference of the shaft at this diameter. The intermediate diameter of the shaft of the plunger 60 is somewhat less than the diameter of the spring 58, which surrounds it and ensures that the movement of the plunger 60 is constrained throughout its travel. About midway down the plunger, it tapers to its smallest diameter, and this portion of the plunger shaft extends through a hole in the constraining member 54 and through the gasket between the base of the constraining member 54 and the gas reservoir 64, and ends in the valve cap, which sits tightly against the gasket, forming a seal. The hole in the centre of the gasket has a diameter sufficiently larger than the diameter of the piston at that point, to allow the gas to flow. Upon depressing the nozzle head 50, by depressing the flange 68 for example, the nozzle base in turn depresses the plunger 60. As the plunger is lowered, the valve cap 70 leaves the gasket 66 and allows the pressurised gas inside the gas reservoir 64 to escape through the hole in the centre of the gasket and out through the nozzle's hollow shaft. When the plunger 60 is in the depressed state, both the nozzle spring 52 and the plunger spring 62 are in compression. When the pressure applied to the nozzle head 50 is released, the nozzle spring 52 forces the nozzle head 50 upwards, and the plunger spring 62 forces the plunger 60 upwards, bringing the valve cap 70 back against the gasket 66 and closing the valve. In this way the burner nozzle and its incorporated valve is operated in the opposite manner to conventional burner nozzles, and operating means more suited to the ergonomics of the device in which it is incorporated may be designed. Also, if any weakness or failing of the springs 52 and/or 62 occurs, the valve's natural tendency would be to close under the gas pressure. The plunger spring 62 is not required to be as stiff as the equivalent spring in a conventional burner nozzle, as the nozzle spring 52 does most of the work. Referring to Fig. 8, the resilient means for lifting the nozzle head 50 may take a form other than a compression spring 52, such as the resilient member 53 shown here. The resilient member 53 in this embodiment is in the form of a bellows, resembling (in three dimensions) two cones attached base to base. As seen in section here, it has approximately the form of two angle brackets, thus: <>. The angles of these brackets are reduced as the nozzle head 50 is depressed. The member springs back to its original shape, forcing the nozzle head 50 upwards, when the downwards force is released. If the member 53 is sufficiently resilient, it may itself form an adequate seal with the constraining member 64. However, it may be preferable to include an O-ring (not shown), like the O-ring 58 of Fig. 7, to provide a seal between the resilient member 53 and the constraining member 64. Naturally, different resilient means could be associated with both the nozzle head 50 and the plunger 60 and achieve a similar operation. The plunger spring 62 may indeed be wholly replaced by resilient means associated with the nozzle head 50 if the plunger 60 is secured to the nozzle head 50. It will be apparent to persons skilled in the art that other modifications to the described embodiments are possible whilst still including the essential elements of the invention as defined by the appended claims.

Claims: Claims 1. A gas helper comprising a housing which comprises a flame port portion (20), a reservoir portion (10) including a tapered nozzle (11) which is raised and lowered to operate the reservoir valve, a flame port tube (32) extending from the tapered nozzle to the flame port at the remote end of the flame port portion (20), and connection means coupled to the flame port tube (32), characterised in that the connection means comprise a tubular coupling element (31) of flexible and resilient material to expandingly surround the nozzle (11), said connection means or the flame tube port (32) being fixed to the housing by anchoring means (30) in the region of the coupling of the connection means to the flame port tube. 2. A gas helper according to claim 1 wherein the anchoring means (30) comprises a fork element (34). 3. A gas helper according to claim 2 wherein the anchoring means includes a further fork element (35) supporting the central region of the coupling element. 4. A gas helper according to any previous claim wherein the nozzle (11) is separated from the connection means when the valve is closed. 5. A gas helper including a burner nozzle comprising a nozzle head (50), a resilient means (52; 53), and a valve, such that when the nozzle head is depressed, the nozzle head opens the valve and deforms the resilient means so that upon releasing the nozzle head the resilient means closes the valve and returns the nozzle head to its original position. 6. A gas helper according to Claim 5 wherein the valve includes a plunger (60) having a valve cap. 7. A gas helper according to Claim 6 wherein the resilient means comprises a spring (58) coiled about the plunger. 8. A gas helper according to any of claims 5 to 7 wherein the resilient means include a resilient means (53) incorporated into the nozzle head. 9. A gas helper according to Claim 8 wherein the resilient means is of a substantially V-shaped section made from resilient material. 10. Any novel and inventive feature or combination of features specifically disclosed herein within the meaning of Article 4H of the International Convention (Paris Convention).

Inventors: ROGELET THIERRY, ROGELET, THIERRY
Applicants: CRICKET SA, ROGELET THIERRY, CRICKET S.A., ROGELET, THIERRY
Application year: 1999
Main classification: F23Q2
IPC codes: F23Q2