Adjustable flame torch burner

Abstract

A torch burner mechanism includes a fuel supply tube having a fuel exit orifice and a burner tube spaced from the exit orifice of the fuel supply tube. The burner tube includes an internal conduit aligned with the exit orifice and defining a concentrated flow path. The mechanism further includes structure defining one or more alternative conduits spaced from the internal conduit that define a diffuse flow path, and a venturi mixing tube movably arranged between the fuel supply tube and the burner tube. An actuator connected to the venturi mixing tube is operable to adjust a position of the venturi mixing tube to select either the concentrated flow path for a concentrated flame or the diffuse flow path for a diffuse flame.

Description

011430.02565ADJUSTABLE FLAME TORCH BURNERFIELD OF THE DISCLOSURE

[0001] The present disclosure relates to burner mechanisms for hand-held torches designed to ignite and burn a fuel and air mixture.BACKGROUND OF THE DISCLOSURE

[0002] As used herein, the term “torch” broadly refers to a manually operable device for igniting fuel to generate a flame, including but not limited to pocket lighters, utility lighters, torches, and the like.

[0003] Three types of mechanisms are generally known for adjusting characteristics of a flame generated by a torch: i) an adjustable release valve for metering the flow rate of fuel from a fuel reservoir of the torch to change the length of the flame, ii) an adjustable closure slide for partially or fully covering venturi air holes in a venturi mixing tube of the torch to control the amount of oxygen mixing with the fuel, thereby allowing continuous adjustment between a higher temperature blue flame in a fully open setting and a lower temperature yellow flame in a fully closed setting, and iii) a set of different burner heads providing different flameshaping effects, such that a user may choose and install a desired burner head prior to operating the torch.

[0004] The first type of mechanism mentioned above not only reduces the length of the flame, it also reduces the intensity of the flame.

[0005] The second type of mechanism mentioned above changes the intensity of the flame, but not its shape.

[0006] The third type of mechanism mentioned above requires a temporary cessation of use of the torch while a changeover task is performed by the user to switch from one flame shape to another flame shape, and loss of one or more burner heads in the set is a possibility.

[0007] There is a need for an adjustable flame torch burner which allows a user to easily adjust flame shape without sacrificing intensity and without installing a different burner head.011430.02565SUMMARY OF THE DISCLOSURE

[0008] The present disclosure provides a torch burner mechanism for a flame torch burner which allows a user to easily adjust flame shape without reducing flame intensity and without installing a different burner head on the torch burner.

[0009] A torch burner mechanism according to an embodiment of the disclosure generally comprises a fuel supply tube, a burner tube including an internal conduit, structure for defining one or more alternative conduits, a venturi mixing tube between the fuel supply tube and the burner tube, and an actuator connected to the venturi mixing tube and operable by a user to adjust a position of the venturi mixing tube.

[0010] The fuel supply tube has an exit orifice through which fuel flows from the fuel supply tube.

[0011] The burner tube is spaced from the exit orifice of the fuel supply tube and the internal conduit communicates from an inlet end to an outlet end of the burner tube. The internal conduit is aligned with the exit orifice of the fuel supply tube and defines a concentrated flow path.

[0012] The one or more alternative conduits are spaced from the internal conduit, and define a diffuse flow path. The diffuse flow path may surround the concentrated flow path.

[0013] The venturi mixing tube is arranged between the fuel supply tube and the burner tube and has an entry end aligned with the exit orifice of the fuel supply tube to receive fuel flowing from the fuel supply tube, a discharge end, a passageway communicating from the entry end to the discharge end, and at least one venturi hole extending radially through the venturi mixing tube and communicating with the passageway.

[0014] The actuator is operable to adjust the venturi mixing tube between a first position wherein the discharge end of the venturi mixing tube is spaced from the inlet end of the burner tube for selecting the concentrated flow path and a second position wherein the discharge end of the venturi mixing tube is adjacent the inlet end of the burner tube for selecting the diffuse flow path. In an embodiment of the torch burner mechanism, the actuator includes a flame adjustment button coupled to the venturi mixing tube, wherein the flame adjustment button is slidable relative to the burner011430.02565tube. The flame adjustment button may be movable within a recessed slot of the torch burner housing. The flame adjustment button may be moved through a range of travel limited by the first position and the second position to locate the venturi mixing tube at any selected intermediate position between the first position and the second position, whereby continuous adjustment of the flame between a full precision condition and a full diffuse condition is possible.

[0015] The torch burner mechanism of the present disclosure allows the user to easily adjust the flame shape without decreasing fuel flow such that flame intensity is maintained when the flame shape is adjusted.BRIEF DESCRIPTION OF THE DRAWING VIEWS

[0016] The nature and mode of operation of the present disclosure will now be more fully described in the following detailed description taken with the accompanying drawing figures, in which:

[0017] Fig. l is a perspective view showing a torch formed in accordance with an embodiment of the present disclosure;

[0018] Fig. 2A is a cross-sectional view of the torch shown in Fig. 1, wherein a burner mechanism of the torch is set at a precision flame configuration thereof;

[0019] Fig. 2B is an enlarged cross-sectional view of a portion of the burner mechanism shown in Fig. 2A;

[0020] Fig. 3 A is a view similar to that of Fig. 2A, wherein the burner mechanism is set at a diffuse flame configuration thereof;

[0021] Fig. 3B is an enlarged cross-sectional view of a portion of the burner mechanism shown in Fig. 3 A;

[0022] Fig. 4 is a generally front perspective view of a venturi mixing tube of the burner mechanism;

[0023] Fig. 5 is a generally rear perspective view of the venturi mixing tube shown in Fig. 4;

[0024] Fig. 6 is a generally front perspective view of a burner tube of the burner mechanism;011430.02565

[0025] Fig. 7 is a generally rear perspective view of the burner tube shown in Fig.6;

[0026] Fig. 8 is a front axially-directed view of the burner tube shown in Figs. 6 and 7;

[0027] Fig. 9 is a generally rear perspective view showing components of the burner mechanism in the diffuse flame configuration thereof; and

[0028] Fig. 10 is a front axially-directed view of the burner mechanism components shown in Fig. 9.DETAILED DESCRIPTION

[0029] Fig. 1 shows a torch 10 formed in accordance with an embodiment of the present disclosure. Torch 10 comprises a housing 12 sized to be grasped in a hand of a user. Torch 10 may also comprise an ignition trigger 14 and a safety button 16 mounted on housing 12 for controlling ignition. Torch 10 further comprises as burner head 18 from which a flame generated by ignited fuel extends during use of the torch, a fuel valve control slider 20 operable by a user to control a flow rate of fuel delivered to burner head 18, and a flame adjustment button 22 which may be movable within a recessed slot 23 of housing 12 for adjusting flame characteristics as described in greater detail below.

[0030] Reference is now made to Figs. 2A and 2B, which show internal structure of torch 10 within housing 12 and burner head 18. Torch 10 comprises a fuel reservoir 24 for containing pressurized fuel such as butane. Burner head 18 is in communication with fuel reservoir 24 by way of a fuel valve 26 associated with fuel reservoir 24, a fuel supply tube 28 terminating at an exit orifice 30 through which fuel flows in an axial direction from the fuel supply tube, and a venturi mixing tube 32 having an entry end 32A aligned with exit orifice 30 of fuel supply tube 28 to receive fuel flowing from the fuel supply tube. As may be seen, venturi mixing tube 32 extends from housing 12 into burner head 18 and terminates at a discharge end 32B. Venturi mixing tube 32 includes an axial passageway 34 communicating from the entry end 32A to the discharge end 32B, and at least one discharge port 36 extending radially through the venturi mixing tube and communicating with the axial011430.02565passageway 34. As shown in Figs. 4 and 5, venturi mixing tube 32 may have four discharge ports 36 angularly spaced about a longitudinal axis of the venturi mixing tube near discharge end 32B, and an axially-aligned discharge hole 37 through discharge end 32B. As illustrated by the disclosed embodiment, discharge hole 37 may have a cross-sectional area smaller than the cross-sectional area of each discharge port 36.

[0031] Burner head 18 may include a burner sleeve 38 receiving a front portion of venturi mixing tube 32 and a rear portion of a burner tube 40. Burner tube 40 includes an inlet end 40A, an outlet end 40B, and an internal conduit 42 communicating from inlet end 40 A to the outlet end 40B. A forward tip portion of burner head 18 may include a burner collar 54 surrounding and stabilizing burner sleeve 38 and burner tube 40. As may be understood, internal conduit 42 may be aligned with the exit orifice 30 of fuel supply tube 28 in the axial direction of flow and defines a concentrated flow path which may extend in the axial direction.

[0032] Ignition trigger 14 is manually depressible further into housing 12 to open fuel valve 26 and release fuel from fuel reservoir 24 to flow through fuel supply tube 28, exit orifice 30, venturi mixing tube 32, burner sleeve 38, burner tube 40, and burner collar 54. Torch 10 further includes a piezoelectric igniter 50 arranged to be compressed by ignition trigger 14 when the ignition trigger is depressed into housing 12 to generate a spark at the tip of a connected lead wire (not shown) to ignite fuel as the fuel flows out of burner head 18. Safety button 16 may be arranged and configured to block or prevent ignition trigger 14 from being depressed unless safety button 16 is also depressed simultaneously with the ignition trigger.

[0033] Figs. 2A and 2B depict a precision flame setting of torch 10 wherein flame adjustment button 22 is at a rearward position relative to housing 12. Figs. 3 A and 3B depict a diffuse flame setting of torch 10 wherein flame adjustment button 22 is at a forward position relative to housing 12. Flame adjustment button 22 is connected to venturi mixing tube 32 such that operation of flame adjustment button 22 adjusts the axial position of venturi mixing tube 32 relative to exit orifice 30 and burner tube 40. In the precision flame setting shown in Figs. 2A and 2B, entry end 32A of venturi mixing tube 32 is positioned proximate to exit orifice 30 while discharge end 32B of011430.02565venturi mixing tube 32 is axially spaced from inlet end 40A of burner tube 40. In the diffuse flame setting shown in Figs. 3 A and 3B, entry end 32A of venturi mixing tube 32 is axially spaced from exit orifice 30 while discharge end 32B of venturi mixing tube 32 abuts with inlet end 40A of burner tube 40. The discharge end 32B of venturi mixing tube 32 and the inlet end 40A of burner tube 40 may include respective chamfers configured to mate with one another during abutment to provide a sealed transition from axial passageway 34 to internal conduit 42 through discharge hole 37.

[0034] Those skilled in the mechanical arts will realize that button 22 may be replaced by another type of actuator operable by a user, such as a rotatable dial, a lever, a handle, or the like. Those skilled in the mechanical arts will further realize that structural connection between flame adjustment button 22 (or another type of actuator) and venturi mixing tube 32 may take many different forms. In the embodiment described herein, flame adjustment button 22 is directly connected to venturi mixing tube 32 by a slider arm 52 integrally formed with flame adjustment button 22 and coupled to a flange 33 at entry end 32A of venturi mixing tube 32, for example by a clamping ring 53 integrally formed on slider arm 52 for engaging with flange 33. Thus, movement of flame adjustment button 22 within recessed slot 23 of housing 12 in a generally rearward direction away from burner head 18 moves venturi mixing tube 32 away from burner tube 40 and toward exit orifice 30. Rearward and forward travel limits of flame adjustment button 22 may be determined by abutment of flame adjustment button 22 against rearward and forward ends of slot 23. Of course, indirect multi-piece linkages may be used to connect flame adjustment button 22 with venturi mixing tube 32.

[0035] When torch 10 is operated in the precision flame setting shown in Figs. 2A and 2B, air is drawn through entry end 32A into axial passageway 34 of venturi mixing tube 32 by the venturi effect caused by a stream of fuel flowing out of exit orifice 30 and mixes with the flowing fuel as it travels through passageway 34 toward discharge end 32B. Most of the flowing air / fuel mixture escapes from venturi mixing tube 32 in non-axial directions via discharge ports 36, while some of the flowing air / fuel mixture escapes in an axial direction via discharge hole 37. Because discharge end 32B of venturi mixing tube 32 is spaced from inlet end 40A of burner011430.02565tube 40, substantially all of the flow is allowed to reorganize as a narrow, axially-directed flow stream that proceeds though internal conduit 42 of burner tube 40, out of outlet end 40B, and through burner collar 54 where it is ignited as it flows out of burner head 18. Consequently, a relatively long and narrow “pencil like” precision flame PF is generated for precision applications such as soldering or cooking.

[0036] When torch 10 is in the diffuse flame setting shown in Figs. 3 A and 3B, air is once again drawn through entry end 32A into axial passageway 34 of venturi mixing tube 32 by the venturi effect caused by a stream of fuel flowing out of exit orifice 30. As compared to the precision flame setting described above, more air is drawn into axial passageway 34 in the diffuse flame setting because the distance between exit orifice 30 and entry end 32A is greater. The air mixes with the flowing fuel as it travels through passageway 34 toward discharge end 32B. Most of the flowing air / fuel mixture escapes from venturi mixing tube 32 in non-axial directions via discharge ports 36, while some of the flowing air / fuel mixture escapes in an axial direction via discharge hole 37. However, because discharge end 32B of venturi mixing tube 32 is arranged to abut with inlet end 40A of burner tube 40, only the relatively small portion of the flowing air / fuel mixture passing through discharge hole 37 is allowed into internal conduit 42 of burner tube 40. The relatively large portion of the flowing air / fuel mixture escaping through discharge ports 36 cannot pass through internal conduit 42 and instead is redirected to follow a radially diffuse flow path defined by one or more alternative conduits spaced from internal conduit 42. Consequently, a relatively short and narrow diffuse flame DF is generated for applications such as heating large areas or cooking.

[0037] In one embodiment, a plurality of alternative conduits may be defined by external features on burner tube 40 and / or by surrounding structure such as burner sleeve 38 and burner collar 54. As may be seen in Figs. 6-8, burner tube 40 may have a cylindrical main body 43 formed to have a plurality of external spline teeth 44 extending axially along main body 43 of burner tube 40, thereby defining a plurality of gaps or channels 45 between adjacent spline teeth 44. Burner tube 40 may also include a circumferential rim 46 at outlet end 40B having an inner diameter chosen to define a plurality of slit openings 48 through which flowing air / fuel mixture may pass011430.02565after traveling along channels 45. An inner wall of burner sleeve 38 may cover channels 45 from inlet end 40A to an axial location spaced from rim 46 where the burner sleeve terminates. Thus, some of the flow through channels 45 passes through the plurality of slit openings 48, and the remaining flow through channels 45 is diverted radially outward to pass between the outer surface of rim 46 and the inner surface of burner collar 54. In this way, the radially diffuse flow path uses multiple alternative conduits at different radii from a central flow axis on which discharge hole 37 is aligned.

[0038] As will be appreciated, configuring flame adjustment button 22 as a sliding button operable through a range of travel allows the user to continuously adjust the flame between a full precision condition and a full diffuse condition by enabling the user to position venturi mixing tube 32 at any selected intermediate axial location between exit orifice 30 and burner tube 40. In this way, the user has precise and immediate control of flame shape. Moreover, the air (i.e., oxygen) content in the fuel mixture is continually adjusted from a relatively low content in the full precision flame setting to a relatively high content in the full diffuse flame setting.

[0039] While the disclosure sets forth exemplary embodiments, the detailed description is not intended to limit the scope of the disclosure to the particular forms set forth. The disclosure is intended to cover such alternatives, modifications and equivalents of the described embodiments as may be included within the scope of the claims.

Claims

011430.02565WHAT IS CLAIMED IS:

1. A torch burner mechanism comprising:a fuel supply tube having an exit orifice through which fuel flows from the fuel supply tube;a burner tube spaced from the exit orifice of the fuel supply tube, the burner tube including an inlet end, an outlet end, and an internal conduit communicating from the inlet end to the outlet end, wherein the internal conduit is aligned with the exit orifice of the fuel supply tube and defines a concentrated flow path;structure defining one or more alternative conduits spaced from the internal conduit, wherein the one or more alternative conduits define a diffuse flow path;a venturi mixing tube between the fuel supply tube and the burner tube, the venturi mixing tube having an entry end aligned with the exit orifice of the fuel supply tube to receive fuel flowing from the fuel supply tube, a discharge end, a passageway communicating from the entry end to the discharge end, and at least one venturi hole extending radially through the venturi mixing tube and communicating with the passageway; andan actuator connected to the venturi mixing tube and operable by a user to adjust a position of the venturi mixing tube between a first position wherein the discharge end of the venturi mixing tube is spaced from the inlet end of the burner tube for selecting the concentrated flow path and a second position wherein the discharge end of the venturi mixing tube is adjacent the inlet end of the burner tube for selecting the diffuse flow path.

2. The torch burner mechanism according to claim 1, wherein the diffuse flow path surrounds the concentrated flow path.011430.025653. The torch burner mechanism according to claim 1, wherein the structure defining the one or more alternative conduits includes external spline teeth on the burner tube defining a plurality of channels therebetween.

4. The torch burner mechanism according to claim 3, wherein the structure defining the one or more alternative conduits further includes a circumferential rim on the burner tube, wherein the circumferential rim has an inner diameter defining a plurality of slit openings communicating with the plurality of channels.

5. The torch burner mechanism according to claim 4, wherein the structure defining the one or more alternative conduits includes a burner collar surrounding and radially spaced from an outer surface of the burner tube.

6. The torch burner mechanism according to claim 3, wherein the structure defining the one or more alternative conduits includes a burner sleeve surrounding the plurality of channels.

7. The torch burner mechanism according to claim 1, further comprising a burner sleeve receiving a front portion of the venturi mixing tube, wherein the front portion of the venturi mixing tube is slidable relative to the burner sleeve.

8. The torch burner mechanism according to claim 7, wherein the burner sleeve receives a rear portion of the burner tube.

9. The torch burner mechanism according to claim 1, wherein the actuator includes a flame adjustment button coupled to the venturi mixing tube, wherein the flame adjustment button is slidable relative to the burner tube.011430.0256510. The torch burner mechanism according to claim 1, wherein the discharge end of the venturi mixing tube abuts with the inlet end of the burner tube in the second position of the venturi mixing tube.

11. The torch burner mechanism according to claim 1, wherein the actuator is operable through a range of travel limited by the first position and the second position to locate the venturi mixing tube at any selected intermediate position between the first position and the second position, whereby continuous adjustment of the flame between a full precision condition and a full diffuse condition is enabled.

Images