Background of the Disclosure

Field of the Disclosure

[0001] The present disclosure relates to cutting, welding, and heating devices and, more particularly, to cutting torches with flashback arrestors.

Discussion of Related Art

[0002] Fuel cutting, welding, or heating devices discharge fuel gas and oxygen from a nozzle for cutting, welding, or heating purposes. A typical torch includes a control body for connecting to separate fuel gas and oxygen supplies, tubes for supplying the oxygen and fuel gas from the control body to a head, and a cutting tip mounted to the head. The cutting tip receives the fuel gas and oxygen from the head and discharges these gases from its nozzle. More specifically, the head includes an interior surface extending around and defining a head cavity, an oxygen port that is open to the head cavity for supplying oxygen to the head cavity, and a fuel gas port that is open to the head cavity for supplying fuel gas to the head cavity. The cutting tip includes multiple passageways for directing the gases from the head to the nozzle.

[0003] In one previous approach, a conventional cutting torch first generates a preheat flame with gases discharged from the nozzle, and the preheat flame is used to heat a metal workpiece. After the preheat flame has heated the workpiece sufficiently, a high velocity cutting oxygen stream is activated and delivered through the nozzle. The high velocity cutting oxygen stream physically removes molten material of the workpiece by oxidation, to cut the workpiece. Typically, a number of valves and related components are provided upstream of the nozzle, such as in the control body, to control the operations of the cutting torch.

[0004] Flashback is a reaction caused in cutting torches by the reverse flow and ignition of the explosive mixture of gases used in the operation of the torch. Flashback typically originates at the nozzle of the torch and is often caused by an obstruction at this point, operator error, improper gas pressure and/or defective equipment. Due to the rapid and explosive nature of flashback, it poses a major safety hazard to the operator of the gas torch and can damage the gas torch and associated equipment.

[0005] Previous approaches for addressing flashback include the use of a sintered material within the torch to be used at the entry point of the gases into the torch. Although this stops the flashback from traveling upstream from the components that supply the gas to the torch, it disadvantageously does not eliminate the effects of flashback within the torch itself. As a result, the torch can still be damaged or the operator can be injured by flashback within the torch.

[0006] In another previous approach, packing material may be installed into the head of a torch or in a tube that is immediately upstream from the head for arresting flashback. However, this packing material may become damaged, such as by becoming clogged with carbon deposits resulting from flashback. As a result, the packing material must be periodically replaced.

Disadvantageously, the removal and replacement of packing material in cutting torches is labor intensive. Additionally, and of significant safety importance, if the packing material is not properly packed it may not perform its intended function, which can result in damage to the torch or injury to its operator.

[0007] In yet another previous approach, a check valve may be installed in each of the oxygen and fuel passageways to allow the oxygen and the fuel to flow in one direction, while preventing the reverse flow. Check valves, however, are mechanical devices that may become unreliable when contaminated with dirt or debris, which can cause the check valve to leak.

Moreover, the check valves cannot prevent flashback flame from propagating upstream once flashback occurs.

Summary of the Disclosure

[0008] In view of the foregoing, there is a need in the art for a flashback arrestor downstream of the head of a cutting torch for restricting flashback into the torch head, and which can be readily used and replaced in a manner that is likely to ensure satisfactory functionality of the flashback arrestor. Exemplary approaches herein provide flashback arrestors disposed proximate the head of a cutting torch for restricting flashback into the torch head. In one approach, a torch assembly is provided including a torch head having a gas passageway formed within a body of the torch head, and a tip coupled to a distal end of the torch head. In some approaches, the tip has a proximal end and a distal end, the distal end of the tip including an exit orifice and the proximal end of the tip having a set of openings in fluid communication with the gas passageway for delivering a gas towards the exit orifice. The torch assembly further includes a filter coupled to the tip at the proximal end thereof, the filter disposed between the set of openings and the gas passageway for restricting flashback into the torch head. [0009] One approach according to the disclosure includes a torch assembly having a torch head including a gas passageway formed within a body of the torch head, and a tip coupled to a distal end of the torch head. The tip has a proximal end and a distal end, the distal end of the tip including an exit orifice and the proximal end of the tip having a set of openings in fluid communication with the gas passageway for delivering a gas towards the exit orifice. The torch assembly further includes a filter coupled to the tip at the proximal end, the filter disposed between the set of openings and the gas passageway.

[0010] Another approach according to the disclosure includes a flashback arrestor for a torch, the flashback arrestor including a torch head including a gas passageway and an oxygen passageway formed within a body of the torch head. The flashback arrestor further includes a tip coupled to a distal end of the torch head, wherein the tip has a proximal end and a distal end, the distal end of the tip including an exit orifice and the proximal end of the tip including a set of openings formed through a flange. The set of openings may be in fluid communication with the gas passageway for delivering a gas towards the exit orifice. The flashback arrestor further includes a filter coupled to the flange and disposed between the set of openings and the gas passageway.

[0011] Yet another approach according to the disclosure includes a device having a torch head including a body, a gas passageway formed through the body, and a tip coupled to a distal end of the torch head. The tip has a proximal end and a distal end, the distal end of the tip including an exit orifice and the proximal end of the tip including a set of openings formed through a flange, wherein the set of openings are in fluid communication with the gas passageway for delivering a gas to the exit orifice. The oxy-fuel device further includes a filter coupled to the flange and disposed between the set of openings and the gas passageway.

Brief Description of the Drawings

[0012] The accompanying drawings illustrate exemplary approaches of the disclosure, including the practical application of the principles thereof, and in which:

[0013] FIG. 1 is an isometric view of a device according to exemplary approaches of the disclosure;

[0014] FIG. 2 is a side cutaway view of the device of FIG. 1 according to exemplary approaches of the disclosure;

[0015] FIG. 3 is an exploded isometric view of the device of FIG. 1 according to exemplary approaches of the disclosure;

[0016] FIG. 4A is an isometric view of tip adaptor of the device of FIG. 1 according to exemplary approaches of the disclosure;

[0017] FIG. 4B is a side cutaway view of the tip adaptor of FIG. 4A according to exemplary approaches of the disclosure;

[0018] FIG. 4C is a top view of the tip adaptor of FIG. 4A according to exemplary approaches of the disclosure;

[0019] FIG. 5A is an exploded isometric view of the tip of the device of FIG. 1

according to exemplary approaches of the disclosure; [0020] FIG. 5B is an isometric view of an internal component of the tip of FIG. 5A according to exemplary approaches of the disclosure;

[0021] FIG. 5C is a side cutaway view of the tip adaptor of FIG. 5A according to exemplary approaches of the disclosure;

[0022] FIG. 6A is an isometric view of another tip for use with the device of FIG. 1 according to exemplary approaches of the disclosure;

[0023] FIG. 6B is an isometric view of the tip of FIG. 6A according to exemplary approaches of the disclosure;

[0024] FIG. 6C is a side cutaway view of the tip of FIG. 6A according to exemplary approaches of the disclosure;

[0025] FIG. 7A is an isometric view of another tip for use with the device of FIG. 1 according to exemplary approaches of the disclosure;

[0026] FIG. 7B is an isometric view of the tip of FIG. 7A according to exemplary approaches of the disclosure;

[0027] FIG. 7C is a side cutaway view of the tip of FIG. 7A according to exemplary approaches of the disclosure;

[0028] FIG. 8A shows an exploded perspective view of an apparatus that prevents the device from being used without a filter installed to exemplary approaches of the disclosure; and [0029] FIG. 8B shows a side cutaway view of the apparatus of FIG. 8 A according to exemplary approaches of the disclosure.

[0030] The drawings are not necessarily to scale. The drawings are merely

representations, not intended to portray specific parameters of the disclosure. Furthermore, the drawings are intended to depict exemplary embodiments of the disclosure, and therefore is not considered as limiting in scope.

[0031] Furthermore, certain elements in some of the figures may be omitted, or illustrated not-to-scale, for illustrative clarity. The cross-sectional views may be in the form of "slices", or "near-sighted" cross-sectional views, omitting certain background lines otherwise visible in a "true" cross-sectional view, for illustrative clarity. Furthermore, for clarity, some reference numbers may be omitted in certain drawings.

Description of Embodiments

[0032] The present disclosure will now proceed with reference to the accompanying drawings, in which various approaches are shown. It will be appreciated, however, that the disclosed torch handle may be embodied in many different forms and should not be construed as limited to the approaches set forth herein. Rather, these approaches are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. In the drawings, like numbers refer to like elements throughout.

[0033] As used herein, an element or operation recited in the singular and proceeded with the word "a" or "an" should be understood as not excluding plural elements or operations, unless such exclusion is explicitly recited. Furthermore, references to "one approach" of the present disclosure are not intended to be interpreted as excluding the existence of additional approaches that also incorporate the recited features.

[0034] Furthermore, spatially relative terms, such as "beneath," "below," "lower," "central," "above," "upper," and the like, may be used herein for ease of describing one element's relationship to another element(s) as illustrated in the figures. It will be understood that the spatially relative terms may encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0035] As stated above, exemplary approaches herein provide flashback arrestors disposed proximate the head of a cutting torch for restricting flashback into the torch head. In one approach, a torch assembly is provided including a torch head having a gas passageway formed within a body of the torch head, and a tip coupled to a distal end of the torch head. In some approaches, the tip has a proximal end and a distal end, the distal end of the tip including an exit orifice and the proximal end of the tip having a set of openings in fluid communication with the gas passageway for delivering a gas towards the exit orifice. The torch assembly further includes a filter coupled to the tip at the proximal end thereof, the filter disposed between the set of openings and the gas passageway for restricting flashback into the torch head.

[0036] Referring now to FIGs. 1-4, an oxygen-fuel or air-fuel device, such as a torch, will be described in greater detail according to exemplary embodiments of the disclosure. As shown, an oxygen-fuel device 10 (hereinafter "device") includes a torch head 12 having a body 14 for receiving a cutting oxygen and a mixed oxygen-fuel gas via respective inlets 16 and 18 formed in the body 14. The torch head 12 further includes exterior threads 20 that engage a first tip fastener 24, such as a nut, for securing a tip 30 to a distal end 32 of the torch head 12. The torch head 12 further includes an oxygen passageway 34 for receiving the cutting oxygen, and a gas passageway 36 for receiving the mixed oxy-fuel gas. In accordance with some embodiments of the present disclosure, the mixed oxy-fuel gas includes a combination of oxygen and a gaseous fuel, such as acetylene, or the like. However, it will be appreciated that the present disclosure is also applicable to "post-mixed" cutting torches.

[0037] The cutting oxygen and the mixed oxy-fuel gas illustrated in FIGs. 1-2 are representative of gas supplies and cutting torch components that are upstream from a proximal end 35 of the torch head 12. In one example, the cutting oxygen and the mixed oxy-fuel gas illustrated in FIGs. 1-2 are representative of a control body connected to separate fuel gas and oxygen supplies, and tubes for supplying the oxygen and fuel gas from the control body to the torch head 12, with the control body including valves and related components for controlling the operations of the device 10.

[0038] In the embodiment shown, the device 10 further includes a tip adaptor 40 secured within the torch head 12, coaxially with the oxygen passageway 34, so as to couple the tip 30 to the torch head 12. Specifically, the tip adaptor 40 has a proximal end 42 secured within a bore of the torch head 12, and a distal end 44 secured to the tip 30 by a second fastener 46, such as a nut. The tip adaptor 40 may include a set of threads 48 disposed along an exterior surface 50 thereof for engagement with the second fastener 46, and a central ring 47 of a flange 49 for engagement with an inner seating surface 51 (FIG. 1) of the first tip fastener 24. [0039] The tip adaptor 40 further includes a plurality of internal fluid passageways extending between the proximal end 42 and the distal end 44 thereof. More specifically, the tip adaptor 40 includes an inner passageway 54 extending from the proximal end 42 to the distal end 44, the inner passageway 54 aligned with the oxygen passageway 34 for transporting the cutting oxygen to the tip 30. As shown, the tip adaptor 40 further includes a plurality of outer passageways 56 surrounding the inner passageway 54, the plurality of outer passageways 56 extending from an upper surface 57 (FIG. 4) of a flange 58 to the distal end 44. The plurality of outer passageways 56 are configured to transport the mixed oxy-fuel gas to the tip 30.

[0040] In one embodiment, the device 10 includes an annular gas ring 60 coupled between the tip adaptor 40 and the torch head 12 for transporting the mixed oxy-fuel gas to the tip adaptor 40. As shown, the annular gas ring 60 including a central opening 62 aligned with the oxygen passageway 34 and one or more conduits 63 extending into the gas passageway 36 for receiving the mixed oxy-fuel gas. As a result, the oxy-fuel gas passageway 36 is in fluid communication with the plurality of outer passageways 56 of the tip adaptor 40. Additionally, the annular gas ring 60 may include a set of threads 66 for engaging the body 14 of the torch head 12.

[0041] Turning now to FIGs. 3 and 5A-C, the tip 30 of the device 10 will be described in greater detail. In this embodiment, the tip 30 is coupled to the distal end 32 of the torch head 12 via the tip adaptor 40. The tip 30 has a proximal end 70 and a distal end 72, the distal end 72 including an exit orifice 74. The tip 30 may include a shell 75 surrounding an interior component 76. As shown, the shell 75 includes an upper rim 77 for engaging a flange 80 of the interior component 76 and an inner seating surface 73 (FIG. 2) of the second tip fastener 46. A plurality of compression members 79 are disposed at a distal end 81 of the interior component 76, proximate the exit orifice 74 of the tip 30. The plurality of compression members 79 extend circumferentially around the distal end 81 of the interior component 76, and are configured to compress towards a central passageway 78 of the tip 30 as the interior component 76 enters the internal bore of the shell 75.

[0042] The central passageway 78 of the tip 30 is generally aligned with and in fluid communication with the oxygen passageway 34 of the torch head 12 via the inner passageway 54 of the tip adaptor 40. Additionally, the flange 80 includes a set of openings 82 formed therein, the set of openings 82 aligned with and in fluid communication with the oxy-fuel gas passageway 36 via the outer passageways 56 of the tip adaptor 40. In some embodiments, the central passageway 78 includes an additional filter 83 (FIG. 5C) disposed therein. The filter 83 may advantageously smooth the flow of the cutting oxygen before it reaches the exit orifice 74.

[0043] As best demonstrated in FIG. 5C, the set of openings 82 are configured to communicate the oxy-fuel gas within the shell 75, along an exterior surface 84 of the interior component 76, towards the exit orifice 74. In some embodiments, the tip 30 includes a filter 85 coupled at the proximal end 70 thereof, between the set of openings 82 and the gas passageway 38 of the torch head 12. The filter 85 may be a sintered bushing disposed within a channel 88 (FIG. 5B) of the flange 80 of the tip 30. In some embodiments, the filter 85 is an annularly shaped porous element having a plurality of convolute passageways (not shown) that make gas travel difficult. In one non-limiting approach, the porous structure of the filter 85 may be sintered bronze or sintered stainless steel, with a pore size of about ten microns. The pore size is an approximate measure of a representative pore in a direction perpendicular to the flow therethrough. It will be appreciated that the preferred pore size and the number of pores may vary, depending upon many factors associated with the manufacture and operation of the device 10. Further, in accordance with alternative embodiments, the porous structure can be any type of material for allowing the cutting torch to operate in a normal fashion, while also performing a flashback restricting function.

[0044] When the device 10 is in use, the filter 85 extinguishes a flame and/or prevents a flashback from entering the torch head 12 via the outer passageways 56 of the tip adaptor 40. Should a flashback occur, it will only travel so far as the filter 85, which is positioned above the set of openings 82, thus improving safety for an operator of the device 10. Furthermore, by placing the filter 85 within the channel 88 of the tip 30, the filter 85 and the tip 30 may be easily replaced simultaneously.

[0045] Referring now to FIGs. 2 and 6A-C, an additional embodiment of a tip for use with the device 10 will be described in greater detail. Similar to the tip 30 shown in FIGs. 1-5, the tip 90 shown in FIGs. 6A-C may be coupled to the distal end 32 of the torch head 12 via the tip adaptor 40 and the second fastener 46. The tip 90 has a proximal end 91 and a distal end 92, the distal end 92 including an exit orifice 94 formed therein. A central passageway 95 of the tip 90 is generally aligned with and in fluid communication with the oxygen passageway 34 of the torch head 12 via the inner passageway 54 of the tip adaptor 40. In some embodiments, the central passageway 95 includes an additional filter 96 (FIG. 6C) disposed therein. The filter 96 may advantageously smooth the flow of the cutting oxygen before it reaches the exit orifice 94. [0046] The tip 90 further includes a flange 100 at the proximal end 91, the flange 100 including a channel 102 or recess for receiving the filter 85 therein. As shown, the flange 100 includes a set of openings 106 formed therein, wherein the set of openings 106 are aligned with and in fluid communication with the oxy-fuel gas passageway 36 via the outer passageways 56 of the tip adaptor 40. As demonstrated, the set of openings 106 extend from the proximal end 91 to the distal end 92 of the tip 90, and are configured to communicate the mixed oxy-fuel gas towards the exit orifice 94.

[0047] In this embodiment, the tip 90 includes filter 85 disposed at the proximal end 91 thereof, between the set of openings 106 and the gas passageway 38 of the torch head 12. The filter 85 may be a sintered bushing disposed within the channel 102 of the flange 100. As described above, when the device 10 is in use, the filter 85 extinguishes a flame and/or prevents a flashback from entering the torch head 12 via the outer passageways 56 of the tip adaptor 40. Furthermore, by placing the filter 85 within the channel 102 of the tip 90, the filter 85 and the tip 90 may be easily replaced at the same time.

[0048] Turning now to FIGs. 2 and 7A-C, an additional embodiment of a tip for use with the device 10 will be described in greater detail. Similar to the tips described above, the tip 110 shown in FIGs. 7A-C may be coupled to the distal end 32 of the torch head 12, for example, via the first tip fastener 24. In this embodiment, the tip 110 is a unitary design taking the place of, for example, the tip adaptor 40 and the tip 30 shown in FIGs. 1-6. The tip 110 has a proximal end 112 and a distal end 114, the distal end 114 including an exit orifice 116. The tip 110 is secured within the torch head 12, coaxially with the oxygen passageway 34. Specifically, the tip 110 may include a flange 120 for engagement with the inner seating surface 51 of the first tip fastener 24.

[0049] The tip 110 further includes a plurality of internal fluid passageways extending between the proximal end 112 and the distal end 114 thereof. More specifically, the tip 110 includes a central passageway 122 extending from the proximal end 1 12 to the distal end 114, the central passageway 122 configured to transport the cutting oxygen to the exit orifice 116 for engagement with a cutting surface (not shown). In some embodiments, the central passageway 122 includes an additional filter 123 (FIG. 7C) disposed therein. The filter 123 may

advantageously smooth the flow of the cutting oxygen before it reaches the exit orifice 116. As shown, the tip 110 further includes a plurality of outer passageways 126 surrounding the central passageway 122, the plurality of outer passageways 126 extending from an upper surface 130 of the flange 120. The plurality of outer passageways 126 are configured to transport the mixed oxy-fuel gas to the exit orifice 116 for engagement with the cutting surface.

[0050] In this embodiment, the tip 110 includes a filter 135 coupled to the upper surface 130 of the flange 120. As arranged, the filter 135 is positioned between the plurality of outer passageways 126 and the gas passageway 38 of the torch head 12. The filter 135 may be a sintered bushing. As described above, when the device 10 is in use, the filter 135 extinguishes a flame and/or prevents a flashback from entering the torch head 12. Furthermore, by coupling the filter 135 to the tip 110, the filter 135 and the tip 110 may be easily replaced at the same time.

[0051] Referring again to FIGs. 1-6, the operation of the device 10 according to an exemplary embodiment of the present disclosure will be described. Oxygen and fuel are supplied to the torch head 12 while the cutting tip 30 is fully mounted thereto. As a result, oxygen flows through the oxygen passageway 34, and fuel flows through each of the upstream fuel or gas passageways 36, the outer passageways 56 of the tip adaptor 40, the filter 85, and then the set of openings 82 of the interior component 76. Described more generally, the filter 85 is positioned outside of the body 14 of the torch head 12, between the fuel or gas passageway 36 and the exit orifice 74 of the tip 30. In some embodiments, as shown in FIG. 2, the device 10 includes an additional filter 71 disposed within the cutting oxygen passageway 34 of the torch head 12. The additional filter 71 may advantageously smooth the flow of the cutting oxygen before it reaches the tip adaptor 40.

[0052] The fuel is then discharged from the tip 30 and ignited to form a preheat flame that is used to heat a metal workpiece. After the preheat flame has heated the workpiece sufficiently, a high velocity cutting oxygen stream is activated and delivered through the device 10 via the oxygen passageway 34. The high velocity cutting oxygen stream physically removes molten material of the workpiece by oxidation, thus cutting the workpiece. If during this operation flashback occurs as a result of reverse flow and ignition of the explosive mixture of gases, such as due to an obstruction at the nozzle, the filter 85 advantageously restricts the flashback from reaching the upstream fuel passageway 36.

[0053] When flashback reaches and is extinguished by the filter 85, solid byproducts of the flashback, such as carbon, are deposited in the pores and convolute passageways of the filter 85. As a result, the filter 85 can eventually become clogged, making it too restrictive to the desired flow of fuel gas therethrough. In this case, and in accordance with one non-limiting embodiment of the disclosure, the tip 30 is preferably discarded in its entirety and replaced with a new cutting tip. Completely discarding the used tip 30 and replacing it with a new one prevents malfunctioning that could occur if a user incorrectly installs a new filter 85 or, even worse, removes and does not replace a clogged filter. In this regard, the tip 30 and the filter 85 can be generally characterized as a "one-piece" consumable item that is completely discarded if/when it becomes clogged. Alternatively, the filter 85 can be readily removable from the tip 30 and is separately replaceable.

[0054] Turning now to FIGs. 8A-B, the device 10 may further include an apparatus that prevents the consumable from being used without a filter being installed. As shown, the apparatus 140 may include a spring element 142, a disc 144, and a retainer 146, wherein a force from the spring element 142 causes the disc 144 to engage a filter 150. When the apparatus 140 is installed, the filter 150 retained within the tip 152 is able to apply a force on and push open the disc 144, thus allowing fluid flow through a passageway 154. When the tip 152 is not installed or the tip 152 is installed without the filter 150, the disc 144 closes against the retainer 146 with the spring force from the spring element 142, thus allowing little or no fluid flow through the passageway 164. In one embodiment, an overhang portion 160 of the disc 144 is configured to engage a shoulder 162 of the retainer 146 when the filter 150 is not present. As shown, the apparatus 140 is configured to engage with and surround a lower extension 166 of the tip adapter 168. In some embodiments, the retainer 146 may engage with an outer surface 170 of the tip adapter 168.

[0055] While the present disclosure has been described with reference to certain approaches, numerous modifications, alterations and changes to the described approaches are possible without departing from the sphere and scope of the present disclosure, as defined in the appended claims. Accordingly, it is intended that the present disclosure not be limited to the described approaches, but that it has the full scope defined by the language of the following claims, and equivalents thereof. While the disclosure has been described with reference to certain approaches, numerous modifications, alterations and changes to the described approaches are possible without departing from the spirit and scope of the disclosure, as defined in the appended claims. Accordingly, it is intended that the present disclosure not be limited to the described approaches, but that it has the full scope defined by the language of the following claims, and equivalents thereof.