Method for producing mixing tube structural component of stove burner

Abstract

The invention provides a method for manufacturing a mixing tube structural member of a stove burner. The method can appropriately prevent a flange part around a base part of a deep-drawn bulged part from having large strain. A method for manufacturing a mixing tube structural member for a stove burner, the method comprising: a bulging part forming step for forming a bulging part (2) bulging toward the surface side of a metal plate (1A) by performing deep drawing on the metal plate (1A) as a raw material, and forming a flange part (19) around the base part of the bulging part (2); and a strain correction step for correcting the strain of the flange section (19) after the bulging section forming step, and in the strain correction step, a punch (7A) having a first press surface (71a) having a convex curved surface shape is used to press the flange section (19) by bringing the first press surface (71a) into contact with the back surface of the flange section (19).

Description

Technical Field

[0001] The invention relates to a method for manufacturing a mixing tube structural component of a stove burner. Background Art

[0002] Stove burners are generally configured to include a mixing tube, as described in Patent Documents 1 to 3. The mixing tube is a member for introducing a mixed gas of fuel gas and air into a plurality of flame holes provided in a burner cover, and the burner cover is usually placed on the upper side of the mixing tube.

[0003] The mixing pipe of such a stove burner is formed by, for example, aluminum die casting, but in this case, the manufacturing cost becomes expensive.

[0004] As a means for reducing the manufacturing cost of the mixing duct, for example, a means of forming the structural members of the mixing duct by press working a metal plate is conceivable.

[0005] However, when the above-mentioned means are adopted, there are problems that need to be improved as described below.

[0006] That is, as a specific example of a structural member of a mixing tube, there is a structural member including a bulging portion bulging toward the surface side (upper surface side) and a flat flange portion located around the base of the bulging portion. When forming the bulging portion by deep drawing a metal plate in order to manufacture such a structural member, the flange portion is susceptible to strain. The strain deforms the flange portion into a convex shape on the back side (convex shape on the lower surface side). In addition, the greater the drawing depth of the bulging portion, the greater the strain. If so, the flange portion becomes non-flat, and therefore when the flange portion assembles other structural members other than the mixing tube, it is difficult to make these flange portions and other structural members properly close contact. As a result, there is a worry that the following undesirable situation will occur: inappropriate gaps or looseness will occur between them. It is expected that this situation can be appropriately eliminated.

[0007] [Prior art literature]

[0008] [Patent Document]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 2001-21147

[0010] [Patent Document 2] Japanese Patent No. 3739915

[0011] [Patent Document 3] Japanese Patent Application Publication No. 2019-27669

[0012] [Patent Document 4] Japanese Patent Publication No. 2002-282952

[0013] [Patent Document 5] Japanese Patent No. 6818229 Summary of the invention

[0014] [Problems to be solved by the invention]

[0015] The present invention is conceived based on the above-mentioned situation, and its subject is to provide a method for manufacturing a mixing tube structural component of a stove burner. When manufacturing the mixing tube structural component of the stove burner through a process of deep drawing a metal plate to form a bulging portion, it can appropriately achieve that a flange portion formed around the base of the bulging portion does not have a large strain.

[0016] [Technical means to solve the problem]

[0017] In order to solve the above-mentioned problems, the present invention adopts the following technical means.

[0018] The manufacturing method of the mixing tube structural component of the stove burner provided by the present invention comprises: a bulging portion forming step, in which a bulging portion bulging toward the surface side of the metal plate is formed on the metal plate by deep drawing as a raw material, and a flange portion is formed around the base of the bulging portion. The manufacturing method of the mixing tube structural component of the stove burner is characterized in that, after the bulging portion forming step, there is also a strain correction step for correcting the strain of the flange portion. In the strain correction step, a punch having a first stamping surface in the shape of a convex curved surface is used, and the first stamping surface is made to abut against the back side of the flange portion, and the flange portion is stamped.

[0019] According to this structure, the following effects can be obtained.

[0020] That is, at the stage where the bulge forming process is finished, even if the flange of the metal plate generates strain (strain caused by the deep drawing of the bulge), the strain can be corrected by the strain correction process performed later. The strain of the flange before correction causes the flange to be deformed into a convex shape on the back side. In contrast, in the strain correction process, the first stamping surface of the punch in the convex curved surface shape is brought into contact with the back side of the flange and stamped, and the flange is actively pressed in the direction opposite to its strain direction to deform it. Therefore, for example, compared with the case where the flange is stamped only with a flat surface, the effect of eliminating the strain of the flange can be excellent. Accordingly, a component having a flange with a properly corrected strain can be appropriately manufactured as a mixing tube structural component of a stove burner. As a result, when the mixing tube structural component is assembled with other mixing tube structural components, the following undesirable conditions can be avoided: a large gap caused by the strain or looseness between the flange and other mixing tube structural components can be avoided.

[0021] In the present invention, the punch preferably includes: a plurality of first blocks, the front end surfaces of which are the first punching surfaces; and a first base portion, wherein the plurality of first blocks are held in a spaced-apart arrangement so as to be in contact with the back surface of the flange portion.

[0022] According to this structure, the manufacturing of the punch used in the strain correction process can be simplified and cost-effective. That is, as another form of the first punching surface of the punch, it can also be formed as a first punching surface that is annular in plan view as a whole to correspond to the flange portion of the mixing tube structural member, but if so, there is a disadvantage that the first punching surface is difficult to process, it is difficult to manufacture the punch, and its manufacturing cost becomes high. In contrast, by using a punch of the structure of a plurality of first blocks, the disadvantage can be eliminated.

[0023] In the present invention, preferably, in the strain correction step, a die having a second stamping surface having a concave or flat shape corresponding to the convex shape of the first stamping surface is also used to stamp the flange portion by sandwiching the first stamping surface and the second stamping surface.

[0024] According to this structure, in the strain correction process, the flange portion is sandwiched between the convex first punching surface of the punch and the concave or flat second punching surface of the die, so the strain correction effect of the flange portion can be further improved. In addition, according to the experiment of the inventor of the present application, it is confirmed that even if the second punching surface is set to a flat surface instead of a concave surface, the strain correction effect intended by the present invention can be fully obtained.

[0025] In the present invention, the die preferably includes: a plurality of second blocks, the front end surfaces of which are set as the second punching surfaces; and a second base portion, wherein the plurality of second blocks are held in a spaced-apart arrangement so as to be in contact with the surface of the flange portion.

[0026] According to this structure, the manufacturing of the mold used in the strain correction process can be simplified and the cost can be reduced. That is, when the second stamping surface of the mold is formed into a second stamping surface that is, for example, annular in plan view corresponding to the flange portion, which is different from the above structure, there is a concern that it is difficult to process and the cost becomes high. In contrast, the above structure can eliminate or reduce such concerns.

[0027] Other features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1(a) is a schematic cross-sectional view of the main parts of an example of a stove burner. Among the upper and lower mixing tube structural members of the stove burner shown in this figure, the lower mixing tube structural member corresponds to an example of a manufacturing object of the manufacturing method of the present invention. Figure 1 (b) is Figure 1 (a) Ib-Ib cross-section view.

[0029] Figure 2 yes Figure 1 (a) Figure 1 (b) is a schematic three-dimensional view of a pair of upper and lower mixing tube structural components of a stove burner.

[0030] Figure 3 (a) is Figure 1 (a) Figure 1 (b) and Figure 2 The cross-sectional view of the lower side of the mixing tube structural member is shown. Figure 3 (b) is Figure 3 (a) is the plan view of Figure 3 (c) is Figure 3 (a) IIIc-IIIc cross-sectional view.

[0031] Figure 4 (a) Figure 4 (b) is a cross-sectional view showing an example of a swelling portion forming step in the manufacturing method of the present invention.

[0032] Figure 5 (a) is through Figure 4 (a) Figure 4 A plan view of a semi-finished product of a mixing tube structural member manufactured by the bulging portion forming step shown in (b), Figure 5 (b) is Figure 5 (a) Vb-Vb cross-sectional view, Figure 5 (c) is Figure 5 (a) Vc-Vc cross-sectional view of .

[0033] Figure 6 (a) is a cross-sectional view showing an example of a strain correction step in the manufacturing method of the present invention, Figure 6 (b) means Figure 6 A plan view illustrating the positional relationship between the semi-finished product of the mixing tube structural member and the plurality of first punching surfaces of the punch shown in (a), Figure 6 (c) is Figure 6 The cross-sectional view of different parts of (a) is equivalent to Figure 6 (b) VIc-VIc cross-sectional view.

[0034] Figure 7 (a) is through Figure 6 (a) Figure 6 (c) is a plan view of a semi-finished product of a mixing tube structural member manufactured by the strain correction process, Figure 7 (b) is Figure 7 VIIb-VIIb cross-sectional view of (a), Figure 7 (c) is Figure 7 (a) VIIc-VIIc cross-sectional view, Figure 7 (d) is Figure 7 (a) VIId-VIId cross-sectional view.

[0035] Figure 8 Yes Figure 7 (a)~ Figure 7 (d) is a cross-sectional view showing an example of a semi-finished product of a mixing tube structural member being subjected to a first finishing process.

[0036] Fig. 9 Yes Figure 7 (a)~ Figure 7 (d) is a cross-sectional view of an example of a semi-finished product of a mixing tube structural member being subjected to a second finishing process.

[0037] Fig.10 It is a cross-sectional view of the main parts showing another example of the present invention.

[0038] [Explanation of Symbols]

[0039] 1: Plate area

[0040] 1A: Metal Plate

[0041] 2: Bulging part

[0042] 7A: Punch

[0043] 7B: Mold

[0044] 19: Flange

[0045] 70A: The first piece

[0046] 70B: The second block

[0047] 71a: First stamping surface

[0048] 72b: Second stamping surface

[0049] 72A: First base

[0050] 72B: Second base

[0051] B: Stove burner

[0052] M: Mixing tube

[0053] ML: Mixing tube structural member (mixing tube structural member on the lower side)

[0054] ML': Semi-finished product of hybrid tube structural components DETAILED DESCRIPTION

[0055] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0056] First, for ease of understanding, Figure 1 The structure of the stove burner B shown in (a) will be described. In this embodiment, the mixing tube structural member ML on the lower side of the stove burner B described later is a manufacturing object.

[0057] The stove burner B includes a mixing tube M, a burner cover 50, a temperature sensor 53, a spark plug 51, and a gas nozzle 52. The mixing tube M is formed by combining a pair of mixing tube structural members MU and ML on the upper side and the lower side to form a mixed gas flow path 6. Fuel gas is ejected from the gas nozzle 52, and the fuel gas is in the tubular flow path portion 6a from the vicinity of the air supply port 60 toward the mixed gas flow path 6. As a result, primary air flows into the mixed gas flow path 6 from the air supply port 60, and the mixed gas of the primary air and the fuel gas travels in the mixed gas flow path 6 and is finally guided to a plurality of flame holes 50b provided in the head 50a of the burner cover 50. The fuel gas in the mixed gas flowing out from these multiple flame holes 50b to the outside is ignited by the spark plug 51 and burns.

[0058] The upper mixing tube structural member MU is formed by, for example, stamping a metal plate such as a stainless steel plate. The mixing tube structural member MU includes a bulging portion 4 and an upward convex portion 30 (see also Figure 2 ). The bulge 4 includes a cylindrical peripheral wall portion 40 rising upward from the plate-shaped area 3, and an upper wall portion 41 connected to the upper part of the peripheral wall portion 40, and a rim hole portion 43 is provided on the upper wall portion 41. The upward convex portion 30 is an upper side wall portion constituting the tubular flow path portion 6a and having a substantially semicircular cross-section with a groove portion 30a formed on the lower surface side. The bulge 4 functions as a support platform for the burner cover 50. The rim hole portion 43 (and the rim hole portion 23 described later) can be used as a guide hole portion for inserting the barrel portion 50c of the burner cover 50 and the temperature sensor 53. There is a gap between the rim portion 44 of the rim hole portion 43 and the barrel portion 50c of the burner cover 50, and the mixed gas supplied to the second area 61b of the chamber 61 described later of the mixed gas flow path 6 is guided to the flame hole 50b of the burner cover 50 by passing through the gap.

[0059] The lower mixing tube structural member ML is formed by stamping a metal plate such as a stainless steel plate, similarly to the upper mixing tube structural member MU. Figure 2 ,and Figure 3 (a)~ Figure 3 As fully indicated by (c), the bulge portion 2 and the downward convex portion 10 are included. The bulge portion 2 includes a cylindrical peripheral wall portion 20 rising upward from the plate-shaped region 1 and an upper wall portion 21 connected to the upper portion of the peripheral wall portion 20, and the upper wall portion 21 is provided with a punching hole portion 23 as follows, that is, a punching hole portion 23 having a punching edge portion 24 protruding downwardly provided on the peripheral portion. Figure 1 As shown in (a), the barrel portion 50c of the burner cover 50 is fitted into the burring hole portion 23. The downward convex portion 10 is a substantially semicircular cross-section having a groove portion 10a formed on the upper surface side and constituting the lower side wall portion of the tubular flow path portion 6a.

[0060] like Figure 1 As shown in (a), the bulge 2 is a portion where a chamber 61 of a mixed gas flow path 6 is formed between the two bulges 2 and 4 by being embedded in the lower portion of the bulge 4 of the mixing tube structural member MU on the upper side. In addition, the chamber 61 includes a first area 61a sandwiched between the peripheral wall portions 20 and 40 of the two bulges 2 and 4, and also includes a second area 61b sandwiched between the upper wall portions 21 and 41 of the two bulges 2 and 4. A pair of step portions 22 (see FIG. 2 ) extending obliquely in the vertical height direction are formed on the peripheral wall portion 20 of the bulge 2 (see FIG. 2 ). Figure 2 , Figure 3 (a)~

[0061] Figure 3 (c)). The pair of step portions 22 is used to divide and form the mixed gas flow path 6. A first region 61a of the chamber 61 is formed in the region between the peripheral wall portion 20 and the peripheral wall portion 40, which is closer to the tubular flow path portion 6a than the pair of step portions 22, and a second region 61b of the chamber 61 is connected to the tubular flow path portion 6a via the first region 61a.

[0062] Figure 4 (a) Figure 4 (b)~ Fig. 9 An example of a method for manufacturing the lower mixing tube structural member ML is shown and its contents are described below.

[0063] To manufacture the lower mixing tube structural member ML, first perform the following steps: Figure 4 The bulge forming step (primary bulge forming step) as shown in (a) of FIG. 1 is performed, and then the second bulge forming step and the third bulge forming step are performed, thereby manufacturing the bulge Figure 5 (a)~ Figure 5A semi-finished product ML' of a mixing tube structural member as shown in (c) (the semi-finished product ML' is subsequently processed and so has a different structure but the same reference numerals).

[0064] That is, in Figure 4 In the initial bulge forming step shown in (a), a deep drawing process is performed on a flat metal plate 1A to form a prototype bulge 2A. The prototype bulge 2A is the final bulge 2 (see Figure 3 (a)~ Figure 3 The prototype bulge 2A is a part of the prototype of (c) and has a peripheral wall portion 20 rising upward (rising toward the surface side) from the plate-shaped region 1 of the metal plate 1A, and an upper wall portion 21. It is preferred that the height H1 of the prototype bulge 2A is set to be higher than the final finishing target height H3 of the bulge 2 (see Figure 3 The height of the prototype bulge 2A is reduced by repeating the bulge forming step, so that its size is close to the final target size. If this method is adopted, the bulge 2 can be appropriately suppressed from becoming a thin-walled state, so that cracks, etc., can be prevented from occurring in the bulge 2.

[0065] Furthermore, in the plate-shaped region 1, a region around the base of the bulging portion 2 (the peripheral wall portion 20), namely, the flange portion 19, is strained, and in fact, Figure 4 (a) The non-flat shape as shown by the imaginary line La (in this regard, Figure 4 The same is true for (b), and the details of strain will be described later).

[0066] exist Figure 4 In the second bulge forming step shown in (b), based on the prototype bulge 2A, a bulge 2' having a height H2 lower than the height H1 of the prototype bulge 2A is formed. In addition, an initial step 22a which is finally finished into a step 22 is formed on the peripheral wall 20.

[0067] After the second bulging portion forming step, a third bulging portion forming step is performed to manufacture Figure 5 (a)~ Figure 5 In the third bulge forming step, the height H3 of the bulge 2 is further lower than Figure 4 The height H2 of the bulge 2' of (b) is set, and the bulge processing is performed with the height set to the final finishing target size. The peripheral wall portion 20 of the bulge 2 is formed into the shape and size of the final finishing target, achieving Figure 4 The initial step 22a of (b) is enlarged, thereby the step 22 can be finished at the same time. Furthermore, the downward convex portion 10 having the concave groove 10a can be formed in the plate-like region 1 at the same time.

[0068] At the stage where the third bulge forming step is completed, the flange portion 19, which is the area around the base of the bulge 2 in the semi-finished product ML', is deformed and becomes non-flat. Figure 5 (b) Figure 5 In (c), the flange portion 19 is simplified as a flat plate portion inclined at an appropriate angle α. However, this is not the only example, and there is also a case where the flange portion 19 generates strain in a curved manner. In short, the strain of the flange portion 19 causes the flange portion 19 to deform into a convex shape on the back side (convex shape on the lower surface side). It is believed that this strain is generated by the stress of rebound when the metal plate 1A is deep drawn to form the bulge 2.

[0069] After the third bulging portion forming step, a strain correction step of correcting the strain of the flange portion 19 is performed.

[0070] In the strain correction process, the following is used: Figure 6 (a) Figure 6 A punching device A including a punch 7A and a die 7B as shown in (c). Here, the punch 7A includes a plurality of first blocks 70A and a first base portion 72A. The basic form of each of the plurality of first blocks 70A is a rectangular parallelepiped, and the front end surface thereof is provided as a first punching surface 71a in the form of a convex curved surface convex downward. In the present embodiment, the first punching surface 71a is a curved surface with a circular arc shape in cross section, but the present invention is not limited thereto, and can also be provided as a non-circular arc curved surface (a curved surface in which the radius of curvature of each part is not fixed). In addition, it can also be provided as a curved surface that is asymmetrical left and right or front and back (the same applies to the second punching surface 71b described later).

[0071] like Figure 6 As fully indicated in (b), the plurality of first blocks 70A are arranged in a ring shape at intervals in a manner facing the flange portion 19 of the semi-finished product ML' in a plan view and are held on the first base portion 72A. As a holding means for each first block 70A, the following means is used: the plurality of first blocks 70A are respectively embedded in a plurality of recesses 75a provided in the first base portion 72A.

[0072] The mold 7B includes a plurality of second blocks 70B and a second base portion 72B. The plurality of second blocks 70B are similar to the first block 70A, and their basic shape is a rectangular parallelepiped. However, their upward front end faces are provided as second punching surfaces 71b that are concavely curved downward. These plurality of second blocks 70B are provided as Figure 6 The plurality of first blocks 70A shown in (b) are arranged in the same manner (arranged in a ring shape at intervals) and are held by the second base portion 72B. As a holding means, the following means is used: the plurality of second blocks 70B are respectively embedded in a plurality of recesses 75b provided in the second base portion 72B.

[0073] In the strain correction process, Figure 6 As shown in (c), the flange portion 19 of the semi-finished product ML' is clamped and stamped by a plurality of first stamping surfaces 71a and second stamping surfaces 71b of the punch 7A and the die 7B. At this time, it is set that the first stamping surface 71a abuts against the back side of the flange portion 19 (the side where the bulging portion 2 is not bulged), and the second stamping surface 71b abuts against the surface of the flange portion 19. The strain of the flange portion 19 can be corrected by the strain correction process. The strain of the flange portion 19 deforms the flange portion 19 into a convex shape on the back side as described, and the strain correction process is performed in a manner that the flange portion 19 is actively deformed in a direction opposite to its strain direction. Therefore, the correction effect of the strain of the flange portion 19 can be improved.

[0074] like Figure 7 (a)~ Figure 7 As shown in (d), through the strain correction step, a semi-finished product ML' in which the strain of the flange portion 19 is corrected can be obtained. The flange portion 19 can be formed into a flat plate shape or a shape similar thereto.

[0075] In addition, Figure 7 (a)~ Figure 7 In (d), an additional processing portion 18 is provided on a portion of the semi-finished product ML'. The additional processing portion 18 is a portion formed simultaneously when the strain correction process is performed, for example, a portion provided with a cutout portion 18a or a bent portion 18b provided on a portion of the plate-shaped region 1. Figure 6 As shown in (a), the punch 7A is provided with an auxiliary portion 76 for forming the additional processing portion 18. In the present embodiment, the process of setting the additional processing portion 18 is performed simultaneously with the strain correction process. According to this structure, there is no need to perform a dedicated operation process for setting the additional processing portion 18 separately, which is advantageous in reducing the total number of operation processes.

[0076] After the strain correction process is completed, perform the following steps: Figure 8 and Fig. 9 The first finishing process and the second finishing process are shown. Figure 8 In the first finishing process, a punched hole portion 23 is formed on the upper wall portion 21 of the bulged portion 2 of the semi-finished product ML'. Fig. 9 In the second trimming process, the outer shape of the plate-shaped region 1 of the semi-finished product ML' is trimmed to the final target shape ( Fig. 9 shape shown by the imaginary line).

[0077] By going through the above series of steps, it is possible to appropriately manufacture Figure 2 , Figure 3 (a)~ Figure 3(c) shows the lower mixing tube structural member ML.

[0078] In the manufacturing process, by performing the strain correction process, the strain of the flange portion 19 can be appropriately corrected. Figure 1 (a) Figure 1 As shown in (b), when the upper mixing duct structural member MU is overlapped on the lower mixing duct structural member ML, no large gap is generated in the flange portion 19, and they can be assembled appropriately.

[0079] In addition, the punch 7A and the die 7B used in the strain correction process are, as described above, a plurality of first blocks 70A and a second block 70B including a first punching surface 71a and a second punching surface 71b, which are held on the first base 72A and the second base 72B. Therefore, it is also possible to appropriately achieve the simplification and low cost of manufacturing of these punches 7A and the die 7B. That is, if the first punching surface 71a and the second punching surface 71b are respectively formed into a series of connected top-view annular shapes in a manner corresponding to the flange portion 19, there is an unfavorable situation that the processing / manufacturing of these first punching surfaces 71a and the second punching surfaces 71b becomes very complicated. In contrast, through the structure of the present embodiment, the first punching surface 71a and the second punching surface 71b are easily formed, and there is no such unfavorable situation.

[0080] Fig.10 It is another embodiment of the present invention. Fig.10 In the embodiment, the same or similar elements as those in the embodiment are marked with the same symbols as those in the embodiment, and repeated description is omitted.

[0081] Fig.10 The second pressing surface 71b' of the die 7B of the pressing device A' shown in the figure is flat. In this structure as well, the strain of the flange portion 19 can be appropriately corrected by the pressing action of the first pressing surface 71a.

[0082] According to this embodiment, it can be understood that the second punching surface can also be set to be, for example, a flat surface instead of a concave curved surface.

[0083] The content of the present invention is not limited to the content of the above-described embodiment. The specific structure of each step of the method for manufacturing a mixing pipe structural member of a stove burner of the present invention can be freely changed in various ways within the intended scope of the present invention.

[0084] In the above-described embodiment, the swelling portion forming step is performed three times in total, but the present invention is not limited thereto. The swelling portion forming step only needs to be performed at least once.

[0085] Different from the above-described embodiment, the punch or die used in the strain correction process may also be configured to have a structure that does not include multiple first blocks and second blocks having first stamping surfaces and second stamping surfaces (for example, the first stamping surface and the second stamping surface are not separately provided in multiple blocks, but are provided in a punch or die structure in a ring shape or a shape similar to that in top view).

[0086] In the above embodiment, the case of manufacturing the lower mixing tube structural member ML is described, but the present invention is not limited thereto. The present invention can also be used to manufacture the upper mixing tube structural member MU, and as long as it is a mixing tube structural member of a stove burner including a bulging portion and a flange portion, it can be appropriately manufactured using the manufacturing method of the present invention.

[0087] exist Figure 6 (a) Figure 6 (c) and Fig.10 In the punching device A and the punching device A' shown in the figure, the punch 7A is set as the upper die and the die 7B is set as the lower die, but the present invention is not limited to this. Figure 6 (a) Figure 6 (c) and Fig.10 The structure after upside-down inversion is that the punch 7A is set as the lower die and the die 7B is set as the upper die.

Claims

1. A method for manufacturing a mixing tube structural member of a stove burner, comprising: a bulging portion forming step, wherein a bulging portion bulging toward a surface side of a metal plate as a raw material is formed on the metal plate by deep drawing, and a flange portion is formed around a base of the bulging portion, wherein the method for manufacturing a mixing tube structural member of a stove burner is characterized in that: After the bulging portion forming step, there is further provided a strain correction step of correcting the strain of the flange portion. In the strain correction step, the flange portion is punched by using a punch having a first punching surface in a convex curved shape and bringing the first punching surface into contact with the back surface of the flange portion.

2. The method for manufacturing a mixing tube structural member of a stove burner according to claim 1, wherein The punch comprises: A plurality of first blocks, the front end surfaces of which are set as the first punching surfaces; and a first base portion, wherein the plurality of first blocks are arranged to be spaced apart from each other so as to be able to face and contact the back surface of the flange portion.

3. The method for manufacturing a mixing tube structural member of a stove burner according to claim 1 or 2, wherein In the strain correction step, the flange portion is pressed between the first and second pressing surfaces using a die having a concave or flat second pressing surface corresponding to the convex shape of the first pressing surface.

4. The method for manufacturing a mixing tube structural member of a stove burner according to claim 3, wherein The mold comprises: A plurality of second blocks, the front end surfaces of which are set as the second punching surfaces; and a second base portion, wherein the plurality of second blocks are arranged to be spaced apart from each other so as to be able to face and contact the surface of the flange portion.

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