JPH04138522U - cutting tinder - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a cutting nozzle having an outer tube structure that is easy to maintain and provides high productivity in processing and assembly operations while forming a mixed gas passage with a sufficient cross-sectional area. purpose. [Structure] In a cutting nozzle consisting of an inner tube having a cut oxygen hole in the center and an outer tube forming a mixed gas passage in a ring-shaped gap between the outer circumference of the inner tube, the inner circumference of the outer tube is oriented toward the inner circumferential wall. It is characterized in that it is formed into a petal shape having a plurality of substantially wedge-shaped inscribed protrusions extending in the direction, and is configured to be able to be centered on the inner tube via the wedge-shaped inscribed protrusions.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is a cutting flame that performs oxygen cutting while spouting preheated flame from around the cutting oxygen hole. Regarding the structure of the mouth, in particular, the structure of the cutting nozzle configured so that the inner pipe can be centered by the outer pipe. Regarding construction.

0002

[Conventional technology]

For gas cutters that are conventionally configured to emit a preheating flame from around the cutting oxygen hole. The crater used is publicly known (hereinafter referred to as prior art 1), and its configuration is based on Figure 3. To explain briefly, 8 is a crater body attachment threaded along the vertical axis C-C'. A torch head having a mounting hole 8a, with the back side of the mounting hole 8a serving as a tapered portion 8b, Oxygen introduction holes 10a and mixing holes are formed on the vertical axis C-C' of the tapered part 8b and in the enlarged diameter part on the base side. Cut oxygen pipes 10 each having a gas introduction hole 9a and extending to the rear end side of the torch head 8. and the mixed gas pipe 9 are communicated with each other. 4 is a crater body screwed to the torch head 8, and the cutting acid is placed on the vertical axis C-C'. The elementary hole 4a and the mixed gas passage 3 are formed on the outer periphery of the hole 4a, and a spherical shape is formed on the upper end. The contact surface 4b formed in the The oxygen introduction hole 10a and the mixed gas introduction hole 9a on the side of the water head 8 are isolated, and the It is configured so that the corresponding gas flows into the cut oxygen hole 4a on the side of the body 4 and into the mixed gas passage 3. do. In addition, a back nut 6 is screwed onto the outer circumferential thread on the base side of the crater body 4, and the packing 7 to seal against external leakage of the mixed gas.

0003 1' and 2' are the copper inner and outer tubes that make up the tip of the crater, and the inner tube 1' is the threaded part of the inner tube. 1'b to the inner peripheral screw part on the tip side of the crater body 4, and the outer tube 2' to the outer tube contact surface 2'b. are brought into contact with the tip surface of the crater body 4 and attached to the tip side outer circumferential threaded portion through the outer tube nut 5, respectively. It is screwed airtight. The external shape of the inner tube 1' includes an inner tube body 1'c with a substantially hexagonal cross-sectional shape, and a cylindrical inner tube. It consists of a pipe port part 1'e and an inner pipe tapered part 1'd that connects them. The internal shape is a cylindrical outer tube inner hole 2'c, an outer tube port hole 2'e, and connects them. It consists of an outer tube tapered portion 2'd. The outer circumferential wall surface of the inner tube 1' and the inner circumferential wall surface of the outer tube 2' The gap between the outer pipe port hole 2'e and the inner pipe port part 1 forms a part of the mixed gas passage 3. The end of the mixed gas passage 3 formed by the gap with 'e forms a ring-shaped port 3a, and the injection A preheating flame is generated at port 3a by igniting the mixed gas.

0004 The mixed gas is a mixture of oxygen and fuel gas premixed in the mixer of the torch. , especially when the fuel gas is acetylene, its combustion speed is extremely high, and the inner tube 1 ’ and the outer tube 2’ are eccentric, and the distance between the ring-shaped gap of the port 3a is uneven. Otherwise, it may cause backfire. That is, the ring-shaped gap at port 3a is large. From the point where the preheating flame goes up the mixed gas passage 3, the mixed gas introduction hole 9a, and the mixed gas pipe. 9, it reaches the mixer part inside the torch and melts and burns out the torch. Therefore, an adjustment process called an ignition test is included in the final process of making the crater, and the mixed gas is Light it, and with the outer tube nut 5 loosened, tap the outer tube to make sure that the height of the preheating flame is even. I've made adjustments to make it happen. The cause of the preheating flame being unbalanced is improper port 3a. Although it may depend on careful deburring, it is mainly due to unevenness of the ring-shaped gap of port 3a. Therefore, the above adjustment work is required.

[0005] In order to eliminate this problem, the diagonal diameter of the hexagon of the inner tube body 1'c and the outer The inner diameter of the tube inner hole 2'c is formed so that it can be inserted, and the ridgeline of the inner tube body 1'c is used as a guide. The outer tube can be centered. However, there are cases where these copper crater tips are manufactured by cutting. In this case, processing accuracy could not be obtained to the extent that the adjustment step was omitted.

[0006] In order to eliminate this drawback, the outer tube is made by drawing or pressing a copper tube. The inner hole of the outer tube, which has a polygonal cross-sectional shape that inscribes the cylindrical inner tube, is created by cold forming. technology that enables centering by inserting and inserting the outer tube using the inner tube as a guide. Japanese Patent Publication No. 53-42733, hereinafter referred to as Prior Art 2. ) are disclosed. That is, to briefly explain its configuration based on FIG. 4, the internal hollow part is cut and oxygen is The inner tube 22 formed into the channel 21 is formed so that the outer peripheral cross-sectional shape is circular in the longitudinal direction. The inner wall surface of the outer tube 23 has a slightly larger diameter than the outer wall surface of the inner tube 22. A mixing chamber 24 having an annular cross section is formed between the outer tube 23 and the inner tube 22. . The inner wall surface of the outer tube 23 that is in contact with the outer wall surface of the inner tube 22 has a polygonal cross section such as a hexagon. A mixed gas feeding groove 25 is formed in the shape, and the mixing chamber 24 and the mixed gas feeding groove are formed. 25 are in communication. Further, the polygonal inner surface shape of the outer tube 23 is a polygonal shape as shown in FIG. 4(e). It is said that it may be in the form of The outer tube 23 is formed by drawing a pipe-shaped material, and the drawing process The core metal 26 has a cylindrical molded part 27, a polygonal pillar molded part 28, and a port shown in FIG. 4(e). It has a cylindrical molded part 29 corresponding to a hole.

[0007]

[Problem that the idea aims to solve]

However, in the guide structure of Prior Art 2, the mixed gas feeding groove The cross-sectional area of 25 is not sufficient compared to the area of the mixed gas passage 3 of prior art 1. If this happens, a sufficient amount of mixed gas cannot be supplied, resulting in a crater that is prone to backfire. In other words, the inner diameter of the outer tube inner hole 2'c cannot be increased unnecessarily; Exceed the inner diameter equivalent to the remaining after subtracting the wall thickness necessary for mechanical strength from the outer diameter of the outer tube. I can't get it.

[0008] The area A ₀ of the mixed gas passage 3 of Prior Art 1 is determined from the area of the outer tube inner hole 2'c (radius is R) forming the mixed gas passage 3. Since this is the area obtained by subtracting the hexagonal cross-sectional area of the inner tube body 1'c inscribed in c, A ₀ = πR ² - {(R ² √3/2)/2} x 6 = 0.544R ² becomes. On the other hand, the area A' of the mixed gas feeding groove 25 of Prior Art 2 is determined by calculating the area of the inner tube inscribed in the hexagon from the area of the hexagon inscribed in the circle of radius R of the outer tube inner hole 2'c. Since it is the area after subtraction, A'={(R ² √3/2)/2}×6- π(R√3/2) ² = 0.242R ² , and if you compare it with the former area, ( A'/A ₀ )×100(%)=44.5%, and the area of the latter is only 1/2 or less.

[0009] Furthermore, in conventional technology 2, the pipe-shaped material is drawn or pressed. However, plastic forming using a polygonal core metal is difficult because the material at the corners Firstly, it shortens the life of the core metal, and secondly, especially when Pressing requires unnecessary processing loads.

0010 In view of the drawbacks of the prior art, the present invention provides a mixed gas passage having a sufficient cross-sectional area. The structure of the crater tip is easy to maintain and has high productivity in processing and assembly work. The purpose is to provide a cutting crater with a

[0011]

[Means to solve the problem]

This invention features a ring-shaped void between an inner tube with a cut oxygen hole in the center and the outer circumference of the inner tube. In the cutting crater, which consists of an outer tube that forms a mixed gas passage, A flower having a plurality of generally wedge-shaped inscribed projections extending in the axial direction from the inner circumference of the outer tube toward the inner circumferential wall side. The outer tube is formed into a valve shape and can be centered by fitting the outer tube into the inner tube via the wedge-shaped internal protrusion. It is characterized by its efficient composition.

0012

[Effect]

According to this technical means, the cross-sectional shape of the inner circumferential wall of the outer tube is formed into a petal shape having wedge-shaped inscribed protrusions, so that when the outer tube is fitted into the inner tube using the inscribed protrusions as a guide, the inner tube and the outer tube are connected. Both axes of the tubes coincide, so that the ring-shaped preheating flame port formed in the gap between the tip of the outer wall of the inner tube and the tip of the inner wall of the outer tube can be centered concentrically and at equal intervals. Further, since the inner periphery of the outer tube is formed into a petal shape having an inscribed projection, a sufficient cross-sectional area can be secured as a mixed gas passage. That is, without being bound by the standard dimensions of the standard hexagonal bar in Prior Art 1, or by the shape of the regular hexagon inscribed in the inner wall of the outer tube in Prior Art 2, the shape, size, and number of the inscribed protrusions can be changed. Since the area of the mixed gas passage can be secured by determining the outer diameter of the inner tube to be equal to or larger than the area _A0 of the mixed gas passage 10, the defects in conventional techniques 1 and 2 can be overcome. It is.

[0013] Here, when calculating the mixed gas passage, for example, if six inscribed protrusions are provided with a width of 0.4 mm at the tips that contact the inner tube, and the inner diameter of the outer tube is assumed to be 8 mm, then It can be seen that in order for the area of the mixed gas passage to be equal to A ₀ , the outer diameter of the inner tube should be 90.0% of the inner diameter of the outer tube. Since it is possible to drill a cut oxygen hole with a diameter of about 4 mm, a diameter of 7.2 mm is sufficient as the outer diameter of the inner tube. Therefore, in the above assumed case, by providing a gap of 0.4 mm for the mixed gas passage, the same mixed gas passage as in Prior Art 1 can be secured.

[0014] A cylindrical chip made by cutting a copper rod to the appropriate length is cut into a die that is cut into the outer shape of the outer tube. A core metal cut to correspond to the shape of the inner wall of the outer tube is pressed onto the tip. Press fit to form the outer tube. In the cold press operation in Conventional Technology 1, the tip corresponds to the inner diameter of the port. a cylinder, a cylinder corresponding to the outer diameter of the mixing chamber, and a truncated conical tapered part connecting the two cylinders; A core metal consisting of is press-fitted. The press working in this invention is carried out from the taper part of the core metal to the outside of the mixing chamber before the taper part. Since a core metal with a wedge-shaped inscribed protrusion is engraved across the cylindrical portion corresponding to the diameter, the wedge The process of flowing the material into the shaped inscribed protrusion is added to the press process in the prior art 1. become. However, the cross-sectional shape of the inner circumferential wall of the outer tube is petal-shaped, consisting of curves as a whole, and the material Since the material flows easily, the pressing process of the angular cross-sectional shape in the prior art 2 It is expected that the press load will be smaller compared to can.

[0015] In addition, the outer tube can be manufactured by the cold forming process, and the outer tube can be left fitted into the inner tube. Therefore, eliminating the ignition adjustment work in conventional technology 1 simply reduces the machining error of the outer and inner tubes. Since it is a management technology, high production and assembly productivity can be expected. Also, since the outer and inner tubes at the tip of the crater were manufactured in this way, these must be replaced. It can be expected that even ordinary workers can easily perform the work.

[0016]

【Example】

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. However, this fruit The dimensions, materials, shapes, and relative positions of the components described in the examples are particularly specific. Unless there is a specific description, the scope of this invention is not intended to be limited to only that. This is just an illustrative example.

[0017] FIG. 1 shows the main structure of a cutting nozzle according to an embodiment of the present invention, and (A) shows the cutting nozzle according to an embodiment of the present invention. A partial cross-sectional view of the mouth, (B) is a cross-sectional view taken along the A-A' plane of (A), and FIG. 2 is a view of the outside of the cut crater. FIG. 3 is a perspective view of a core metal used to form a tube by press working. 1 and 2 are an inner tube and an outer tube made of copper that constitute the tip of the crater, and the inner tube 1 is attached to the threaded part 1b of the inner tube. The outer tube 2 has the outer tube contact surface 2b attached to the tip of the tip of the crater body 4. They are brought into contact with the end faces and are screwed airtightly into the outer circumferential threads on the distal end side via the outer tube nuts 5, respectively. It is. The external shape of the inner tube 1 includes an inner tube body 1c with a circular cross-sectional shape and a cylindrical inner tube port. The outer tube 2 has a circular inner shape. A cylindrical outer tube inner hole 2c, an outer tube port hole 2e, and an outer tube tapered portion 2d connecting them. It extends in the axial direction from the outer tube taper part 1d to the inner circumferential wall surface of the outer tube inner hole 2c on the back side. Three approximately wedge-shaped inscribed protrusions 2a are formed, and the inscribed protrusions 2a are fitted into the inner tube body 1b. The outer tube 2 is inserted into the inner tube 1 via the inscribed projection 2a. Centering is possible.

The gap between the outer circumferential wall surface of the inner tube 1 and the inner circumferential wall surface of the outer tube 2 forms a part of the mixed gas passage 3, and the gap between the outer tube port hole 2e and the inner tube port portion 1e allows the mixed gas to The end of the passage 3 forms a ring-shaped port 3a, and a preheating flame is generated at the port 3a by igniting the jetted mixed gas. In Prior Art 1, the cross-sectional area of the mixed gas passage 3 formed by the inner tube 1' having a hexagonal flat diameter of 7 mm and the outer tube 2' having an inner diameter of 8 mm is 18.42 mm ² . In the present invention, the outer diameter of the inner tube 1 is 6.5 mm, the inner diameter of the outer tube inner hole 2c is 8.3 mm, and the inscribed projection has a top side of 0.4 mm, a base side of 1.0 mm, and a height of 0.9 mm. When approximated by the area of three trapezoids, the cross-sectional area of the mixed gas passage 3 is 19.02 mm ² , which is sufficient for a mixed gas passage. Incidentally, the diameters of the inner tube port portion 1e and the outer tube port hole 2e are 2.2 mm and 2.7 mm, respectively, so the area of the port is 0.82 mm ² and the area of the mixed gas passage 3 is 2.2 mm and 2.7 mm, respectively. It is more than 20 times the area of .

[0019] FIG. 2 is a perspective view of a core metal for pressing an outer tube according to an embodiment of the present invention. 15 corresponds to the outer tube inner hole 2c, the outer tube taper part 2d, and the outer tube port hole 2e of the outer tube 2, respectively. It has a corresponding body part 16, a tapered part 17, and a port part 18, and from the tapered part 17 to the body part 1. 6, three wedge-shaped grooves 16a are carved. To form the outer tube 2, a tempered copper chip is inserted into a die (not shown), The core metal is press-fitted and cold-pressed. The shape of the inner peripheral wall of the outer tube 2 corresponds to the core metal. In particular, the wedge-shaped groove 16a forms an internal protrusion 2a on the inner peripheral wall side of the outer tube 2. The cross-sectional shape of the outer tube 2 is shaped like a petal. Since the starting end of the wedge-shaped groove 16a is carved from the tapered part, the copper material is Better results in terms of flow, press processing, and core metal life compared to the hexagonal shape of conventional technology 1. I got it. It should be noted that impregnating the surface of the tempered copper rod with lubricant prior to cold pressing is a conventional practice. Depends on upcoming technology.

[0020]

[Effect of the idea]

As described above, according to the present invention, the cross-sectional shape of the inner circumferential wall of the outer tube has a wedge-shaped inscribed protrusion. Since the tube is shaped like a petal, the outer tube can be fitted into the inner tube using the inscribed protrusion as a guide. By doing so, the axes of the inner tube and outer tube are aligned, so that the tip of the outer wall of the inner tube and the tip of the inner wall of the outer tube are aligned. The ring-shaped preheating flame port formed in the gap between the Cutting tinder can be provided. In addition, the inner periphery of the outer tube is formed into a petal shape with inscribed protrusions, so the material has a standard shape. - Cutting crater with sufficient cross-sectional area as a mixed gas passage without being restricted by dimensions can be provided. Furthermore, since the cross-sectional shape of the inner circumferential wall of the outer tube is generally a petal shape consisting of a curved line, The press load is smaller than the conventional press processing with a square cross-sectional shape, and the core metal It is possible to extend the service life of the In addition, the outer tube can be manufactured by the cold forming process, and the outer tube can be left fitted into the inner tube. Since it can be assembled with high precision, it is possible to increase the productivity of processing and assembly work. can. Also, since the outer and inner tubes at the tip of the crater were manufactured in this way, these should be replaced. It can be expected that even an ordinary worker can easily accomplish the task. It has various effects such as

[Brief explanation of drawings]

FIG. 1 shows the main structure of a cutting tip according to an embodiment of the present invention, (a) is a side cross-sectional view of the cutting tip, (b) is (a)
A cross-sectional view of the AA' plane of

[Fig. 2] A perspective view of a core metal for cold forming a cutting nozzle according to an embodiment of the present invention.

[Fig. 3] Side cross-sectional view of a cut crater according to prior art 1

4 shows the main part configuration of a cutting nozzle according to other prior art 2, (a) is a side sectional view of the cutting nozzle, (b) is a partially cutaway perspective view of the outer tube, and (c) is (a) ), (d) is a cross-sectional view along B-B' plane of another example of the cutting nozzle, (e) is a core metal for processing the outer tube shown in (b). Perspective view showing

[Explanation of symbols]

1 Inner tube 1a Cutting oxygen hole 2 Outer tube 2a Inscribed process 3 Mixed gas passage

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Takashi Takeda Tanaka Co., Ltd. 823 Nitta, Koshoku City, Nagano Prefecture Inside the factory

Claims (1)

[Scope of utility model registration request] Claim 1: In a cutting nozzle consisting of an inner tube having a cut oxygen hole at the center and an outer tube forming a mixed gas passage in a ring-shaped gap between the outer circumference of the inner tube, the inner circumference of the outer tube is placed on the inner circumferential wall side. The outer tube is formed into a petal shape having a plurality of substantially wedge-shaped inscribed protrusions extending in the axial direction, and the outer tube is configured to be centered on the inner tube via the wedge-shaped inscribed protrusions. cutting crater