JPS6249524B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in cutting torches, both direct-cutting and mounted, having multiple passages for cutting oxygen and an oxygen-fuel mixture. In one particular aspect, the present invention relates to an improvement in a cutting torch that uses an integral head mixer.

U.S. Patent Application No. 373,043, entitled "Practical Torch with Head Mixer," dated April 29, 1982,
To heat the metal before the cutting oxygen is used, it is common to benefit from various forms of torches, including mixers, where the high velocity oxygen draws in the fuel and forms a mixture before the mixture is combusted. has been disclosed. Also, problems associated with these are discussed, particularly the tendency to have persistent combustion flashbacks. This sustained combustion burns the torch and injures the operator, such as the welder. One of the ways in which prior art designers have attempted to eliminate flashback, as described in said application, is to use passages of exceptionally small diameter as well as multiple passages for supplying, for example, oxygen and fuel gas. It was possible to use it. Among other methods is the use of heat dissipation devices such as mixing spirals, spiral fins, and the like. These prior art methods are described in the following U.S. Pat.
No. 1262351, No. 1276893, No. 2198342, No.
No. 2263655, No. 2371970, No. 2520001, No.
No. 3091281, No. 4022441, and No. 4248384.

Although the use of small passageways and/or copper spirals for heat dissipation has progressively increased the maneuverability of the torch and reduced flashbacks, including the persistence of flashbacks. There is a need for an economical and simple torch with an integral head mixer that eliminates the difficulties of the prior art.

Thus, there is provided a torch that eliminates the persistence of flashback and the disadvantages of the prior art, yet is economical, easy to manufacture, and does not require multiple holes of small diameter and does not require the use of heat dissipation devices. This is the object of the present invention.

One of the particular objects of the present invention is to have the versatility of a mixer torch with an in-head mixer, which not only can operate on virtually any fuel, but also eliminates the difficulties of the prior art and has all the advantages of the prior art. An object of the present invention is to provide an integral head mixer having an integrated head mixer.

These and other objects will become apparent from the description below with reference to the accompanying drawings.

The present invention eliminates the flashbacks and sustained combustion that occur with fuels such as acetylene, yet provides a torch, such as a cutting torch, with the flexibility inherent in theoretically integrated head mixers. Given. A straight torch or torch and handle combination, with a valve and passageway for cutting oxygen;
Valves and passages for preheating oxygen, valves and passages for fuel gas,
and a head having a tip end with a tip, a passage for cutting oxygen, and a head passage for a mixture of fuel and oxygen, with the following improvements: Among the improvements is an integral head mixer having a passageway for incoming preheated oxygen and a passageway for incoming fuel in the head and including a well in which the passageways for preheated oxygen and fuel terminate. The mixer is inserted into a well, and seals are placed between the ends of the preheating oxygen passage and the preheating fuel passage to separate the annular space for preheating oxygen and the annular space for fuel.
and a holder that tightly holds the mixer within the well. The head has a longitudinally extending mixture passageway for a mixture of fuel and preheated oxygen, which passageway is adjacent to the chip for sealingly receiving the chip while maintaining ventilation between the preheating gas passages. It is connected to an annular passage for preheating. The longitudinal passage is aligned with the central longitudinal axis of the well. The mixer has a generally cylindrical centrally located bore hole aligned with the longitudinal passage of the head and open to an annular space for preheated oxygen formed by the seals, retainers, and well walls on the mixer. It has a borehole entrance end. The mixer passes through this laterally. Seal on the mixer with multiple passages drilled diametrically, with the longitudinal axis of the center of the well against the fuel annular space formed by the well wall at the inlet end.
They each have passages that communicate at an angle of 90° to each other and to the borehole at an angle of 90° to the borehole at the discharge end. In this way, the flashback flame is self-destructing without sustaining combustion at the point of mixing of fuel and preheated oxygen, and without the need for expensive heat dissipation equipment. Seals, such as O-rings, are used on each retainer and mixer to hermetically isolate each annular space. In the illustrated embodiment, at least two diametrically drilled passageways are approximately 90 degrees apart from each other.
and passing laterally through the wall of the mixer to form four short substantially equally spaced passageways adjacent the discharge ends of the passageways;
and substantially immediately mixed within the borehole and longitudinal head passage.

The improvements of the present invention are useful for a wide variety of torches. For example, it may be used in a torch of the type exemplified in the aforementioned patent application No. 373,043, the description and drawings of which are incorporated herein by reference in lieu of details omitted herein. On the other hand, the present invention can be used in gas cutting machines such as US Pat. No. 4,014,528, the description of which is referred to in lieu of details omitted here. The present invention also provides
It can also be used as a mechanical torch, used as a torch connected to a bar or as a single torch, such as for cutting planks and the like. Although there are various types of torches for which this can be used, the overall appearance of the torch is not shown in the drawings. This is because these torches are conventional and well known and do not require a detailed description of their characteristics. As described in Patent Application No. 373,043, a cutting-type torch such as that used by welders includes a connecting tube surrounded by a barrel and a body, etc. Tip end 1 all suspended
The torch head 11 of FIG. 1 with 3 is included. As described and specified in U.S. Pat. No. 4,248,384, there are typically three tubes integrally connected to the head 11 by welding, silver brazing, or the like. Reference is made to the contents of this patent in lieu of details omitted herein. These three tubes include a cutting oxygen tube with a passageway for cutting oxygen passing through it in the longitudinal direction;
It includes a preheated oxygen pipe with a passage for preheated oxygen that penetrates in the longitudinal direction, and a fuel gas pipe with a passage for fuel gas that penetrates in the longitudinal direction. Each of these tubes is also integrally connected to the main body by welding, silver brazing, etc. to connect the cut oxygen passage with the cut oxygen valve to the preheat oxygen passage leading to the preheat oxygen valve and the fuel passage leading to the fuel valve, respectively. Fixed.

The torch head 11 may be a so-called 90 DEG torch head, such as that used by welders to orient the torch tip approximately 90 DEG to the rest of the torch in order to be able to observe the work being done. Alternatively, the torch head may have other orientations, such as a straight head used in mechanical welding processes. As shown, the torch head 11 has a shell 12 for easy connection to a wheel, torch, or mechanical element (not shown), and a threaded receptacle 17 holds the tip 21 in place adjacent its tip end 13. It receives a bushing 19 for holding. As will also be noted, the tip 21 has a centrally located cut oxygen passage leading to a cut oxygen passage 23 in the head 11 and a plurality of preheat mix passages leading to a preheat annular chamber 25 within the head 11. Referring to FIGS. 1-3, the integral head mixer 11 has an incoming preheat oxygen passage 27 and an incoming fuel passage 29 shown in FIG. 2 within the head. The head 11 also includes a well 31 into which the preheating oxygen passage and the fuel passage terminate and connect at their discharge ends, a mixer 33 inserted into this well, and a holder 35 which hermetically holds the mixer within this well. has. Specifically, the retainer 35 and the well 31 have interlocking screws 37.
and an O-ring shaped seal 39 located intermediate the smooth cylindrical wall of each groove and the adjacent cylindrical wall. As shown, this groove is within retainer 35 and is represented by groove 41. Of course, if desired, this groove may be provided in the wall of the well 31 instead of in the holder.

Similarly, the mixer 3 inserted into the well 31
3 has an O-ring shaped seal 43 held hermetically between the smooth wall of this groove and the adjacent cylindrical wall. As shown, the structure 45 is formed externally to the mixer 33, but it is not critical whether it is within the walls of the mixer or the well 31.

The head 11 has a longitudinal passage 47 for a mixture of fuel and preheated oxygen. This longitudinal passage 47 is connected to the preheating annular chamber 25 . As previously indicated, the head 11 is adapted to receive the chip 21 in a sealed manner while maintaining ventilation between the chip preheating passage and the longitudinal passage 47 and the annular chamber 25. Longitudinal passage 47 is aligned with the central longitudinal axis of well 31.

Mixer 33 has a central bore 49 which is substantially cylindrical and aligned with the head longitudinal passage for reasons to be explained below. The reason for this will become clear from the subsequent description of the theory of operation of the present invention. This borehole has an inlet end that opens into a preheated oxygen annular space 51 as clearly shown in FIG. This preheated oxygen annulus is O-ring shaped and is separated from the fuel annulus by a seal 43 intermediate the well wall and retainer 35. The mixer 33 is
held within the holder 35 and adapted to allow preheated oxygen to flow through the annular space upwardly within the annular space and thus into the bore hole 49;
It has a small diameter section 53. Bored hole 49 does not have any restriction as shown by restriction 55 for the prior art shown in FIG. In the embodiment shown in FIG. 4, oxygen flows at a high speed in the same manner as described above in order to draw fuel into the mixing chamber 57.

In an embodiment of the invention, on the other hand, the short passage 59 passes diametrically through the wall of the mixer 33 at approximately 90 DEG to the axis of the fuel annulus 61 as well as to the axis of the borehole. Specifically, a short passageway 59 passes laterally through the mixer 33. It is formed by a plurality of diametrically perforated passageways. With this technique, a single drill passage forms two diametrically opposed passages. As shown, only two such drilled passages are required to form four passages arranged substantially at right angles to each other and equally spaced around the mixer 33. Only.

With this simple and elegant invention, the problem of sustained combustion of flashbacks is eliminated, even if flashbacks occur at all. Although the reasons for the surprising effectiveness of the present invention are not entirely clear, the following theory is offered by way of explanation rather than limitation. In the prior art, at intermediate velocities the fuel rapidly mixes with oxygen, but at high velocities the mixing is not complete from where the fuel arrives, e.g., to a point further downstream from fuel passage 63 in FIG. It doesn't happen. Therefore, if a conventional torch were to backfire, the flame would travel back through the unmixed gases at a slower rate of combustion. This flame does not have enough momentum to advance beyond the fuel entry point and not be extinguished. Rather, the flame stops and continues to burn in the fuel inlet area. Conventional torches therefore sustain combustion without other heat dissipation devices. However, in the present invention, the fuel enters the oxygen at 90°, and the borehole 4
Mix thoroughly even within 9. Any flashback flames thus produced have high velocities, are carried beyond the mixing point, and are extinguished in the rear part of the borehole where only oxygen is present. Specifically, when this torch tip mixer has backfire, the front of the flame travels in the opposite direction to the gas flow and consists of a low-pressure wave and a high-pressure shock wave. Oxygen orifice 5 with prior art oxygen passage
5, the pressure waves can travel to the rear of the mixer so that they are reflected by the retaining plug or retainer 35. When this pressure wave is reflected and travels backwards, it encounters another wave traveling in the opposite direction. When these waves meet, they cancel at a point between fuel passage 59 and retainer 35. Whether or not this theory is completely accurate, the present invention avoids sustained combustion even if flashback occurs, and is useful and satisfies other objects of the invention.

Specifically, the present torch is assembled using conventional manufacturing methods. A well is predrilled in the head and the mixer is inserted with appropriate seals and passageways as described above. In operation, a preheated flame is ignited and set as desired to carry out the cutting process. The preheat flame can be increased or decreased when the present invention is used without exacerbating the problems of flashback and sustained combustion of flashbacks.

Explanations regarding conventional torch chips and the like used in the present invention have been deliberately omitted. Additionally, the torch tip and torch head are formed from corrosion-resistant metal alloys used in the prior art, such as copper alloys and stainless steel. Similarly, the torch tube, body, etc. are formed of the same materials used in the prior art.

Additionally, typical methods of connecting a torch upstream fitting that is sealingly connected to the respective hose connectors and hoses leading to high pressure regulators connected to high pressure vessels for high pressure oxygen and high pressure fuel gases are well known. There is no need to go into details here.

In addition, typical preheated oxygen with a specific structure,
The disconnection oxygen and fuel flow valves are disclosed in the said patent application no.
373043 and may be used in the present invention.

Although a manual cutting torch is the general form of the invention described herein, a cutting torch attachment having a fuel valve on a separate handle may be used as described in U.S. Pat. No. 4,248,384. can. moreover,
Large size heating tips can be used for large size heating processes often used in cutting torch assemblies, automatic machine torches, and the like.

A particular advantage of the present invention lies in an economical unit with a particular design of walls, passages etc. that is more economical than conventional drilled torch heads with heat dissipation spirals etc. The advantage of the head mixer torch is that it not only eliminates the disadvantages of the past, but also provides a unit that can be used with a variety of fuels, with little risk of sustained flashback.

It will be appreciated that the present invention thus achieves the objects set forth above.

Although the invention has been described with some particularity, the present invention is disclosed by way of example and the details of construction and arrangement of various parts may be changed without departing from the spirit of the invention and the scope of the claims. It will be understood that various modifications may be made. Reference is made for this purpose to the claims.

[Brief explanation of the drawing]

1 is a partial cross-sectional view of an embodiment of the present invention, FIG. 2 is a partial cross-sectional view of a mixer inserted into the well of FIG. 1 according to the present invention, and FIG. 2 is a cross-sectional view of the mixer of FIG. 2, and FIG. 4 is a partial cross-sectional view of a prior art device for minimizing the tendency for flashback and sustained combustion to occur at the point of mixing of fuel and preheated oxygen. . 11...Torch head, 31...Well, 33...Mixer, 35...Holder.

Claims (1)

[Claims] 1. A valve for cutting oxygen and its passage, b. A valve for preheating oxygen and its passage, c. A valve for fuel gas and its passage, and d. Cutting the chip with a fixed tip-end head. a head having a head passage for passing oxygen and a head passage for passing a mixture of fuel and oxygen; e. a passage for incoming preheated oxygen and a passage for incoming fuel; an integral head mixer disposed within the head (i) a well connecting the preheat oxygen passage and the fuel passage where they terminate as a discharge end; and (ii) a mixer inserted within the well for the preheating. a mixer having seals intermediate the ends of each of the oxygen and fuel passages so as to separate the preheated oxygen annular space and the fuel annular space; (iii) sealing the mixer within the well; an integral head mixer including a retainer for holding the mixture in the fuel and preheated oxygen mixture; The passageway is connected to the preheating annular passageway for sealingly receiving the chips while maintaining air flow between the preheating passageways, the longitudinal passageway is aligned with the central longitudinal axis of the well, and the mixer is , a centrally located bore hole substantially cylindrical and aligned with the longitudinal passage of the head; the seal on the mixer, the retainer, and the well wall; an inlet end of the borehole leading to an oxygen annular space, the mixer having a hole drilled laterally through the mixer and with the seal on the mixer and the wall of the well at the inlet end. a plurality of diametrical passages each communicating with the fuel annular space formed, the diametrical passages having a longitudinal axis at the central wall location of the wall and a bore hole at the discharge end extending substantially 90 degrees
intersects with ゜ and substantially with respect to the bore hole
90°, so that the leading edge of the flashback flame is self-destructing, not only without sustaining combustion at the point of mixing of the fuel and preheated oxygen, but also without the need for expensive heat dissipation equipment. Torch assembly. 2. The torch assembly of claim 1, wherein the seal includes an O-ring intermediate the smooth groove wall and the smooth cylindrical wall. 3. A torch assembly according to claim 1, wherein the retainer includes a plug with an O-ring sealingly received intermediate the smooth groove wall and the smooth cylindrical wall. Torch assembly. 4. The torch assembly of claim 1, wherein at least two diametrically drilled passages extend laterally through the mixer wall to form four short passages through the mixer wall. , wherein the four short passages are approximately equally spaced so that they are substantially immediately adjacent to the discharge ends of the passages and within the longitudinal passages of the borehole and the head;
A torch assembly adapted to allow homogeneous and complete mixing of the fuel and the preheated oxygen.