JP2011161450A - Welding tool device and welding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and excellently weld two plates to each other even when distortion or warp is present in the plates, and to efficiently execute the welding treatment with high accuracy by suppressing the welding distortion. <P>SOLUTION: A welding tool device 10 includes a first tool member 92 for arranging a workpiece, a second tool member 96 which has an opening part 94 having an opening shape smaller than the outer shape of the workpiece formed, and holds outer circumferential ends of the first tool member 92 and the workpiece, and a third tool member 98 which is arranged at the opening part 94 to hold the inner parts of the outer circumferential end of the first tool member 92 and the workpiece, and forms a space 110 for exposing a welding part between an outer wall surface and the inner wall surface forming the opening part 94 of the second tool member 96. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention uses a welding jig device and a welding jig device for holding a workpiece in which a first plate and a second plate are overlapped and welding the workpiece along a welded portion of an outer peripheral portion of the workpiece. The present invention relates to a welding method for performing welding.

  In general, a solid oxide fuel cell (SOFC) uses an oxide ion conductor, for example, stabilized zirconia, as an electrolyte, and an electrolyte / electrode assembly in which an anode electrode and a cathode electrode are disposed on both sides of the electrolyte. (MEA) is sandwiched between separators (bipolar plates). This fuel cell is normally used as a fuel cell stack in which a predetermined number of MEAs and separators are stacked.

  In this type of fuel cell, a metal separator is used, and a plurality of protrusions (embosses) are formed in order to collect electricity obtained by the power generation reaction from the electrolyte / electrode assembly. Usually, the greater the number of protrusions, the higher the current collection efficiency. Therefore, it is desired to form a large number of protrusions on the current collecting part having a certain area.

  However, when a large number of protrusions are press-formed on the metal plate constituting the separator, there is a problem that the metal plate remains strained during processing and is easily deformed. Therefore, for example, when forming a separator by welding two press-molded metal plates, there is a problem in that a distortion occurs in the welded part and a good welding process cannot be performed.

  Therefore, for example, a welding method for a fuel cell metal separator disclosed in Patent Document 1 is known. This welding method includes a step of combining a pair of metal separators for a fuel cell so that the joining surfaces of the metal separators are overlapped to form a space portion serving as a fluid flow path, and the space portion is evacuated and negatively discharged. The method includes a step of bringing the joint surfaces that have been pressed and overlapped into close contact with each other by atmospheric pressure, and a step of performing overlap welding on the joint surfaces that have been brought into close contact with each other.

JP2009-64593

  However, in Patent Document 1 described above, the inside of the space portion is negatively pressured so as to bring the overlapping joining surfaces into close contact with each other at atmospheric pressure. However, the joining surfaces are reliably brought into close contact with each other only by negative pressure. I can't. For this reason, there exists a problem that the joint surfaces of a pair of metal separator cannot be overlap-welded with high precision.

  In addition, even if the joining surfaces are displaced during welding, the displacement cannot be corrected. In addition, there is a problem that heat distortion generated during welding cannot be satisfactorily suppressed. In addition, in order to generate a negative pressure, it is necessary to install a vacuum pump or the like, which is not economical.

  The present invention solves this type of problem, and even if there is distortion or warpage in the plates, the two plates can be welded easily and satisfactorily, and the welding distortion is suppressed and high accuracy is achieved. An object of the present invention is to provide a welding jig apparatus and a welding method capable of performing various welding processes.

  The present invention relates to a welding jig apparatus for holding a workpiece in which a first plate and a second plate are overlapped and welding the workpiece along a welded portion of an outer peripheral portion of the workpiece.

  In this welding jig apparatus, a first jig member for placing a workpiece and an opening corresponding to the shape of the workpiece are formed, and an outer peripheral end of the first jig member and the workpiece is formed. The second jig member to be sandwiched, and disposed in the opening to hold the inner side of the first jig member and the outer peripheral end of the workpiece, and the outer wall surface and the second jig member And a third jig member for providing a gap for exposing the welded portion between the inner wall surface forming the opening.

  Further, the inner wall surface of the second jig member has a first inclined surface inclined inward toward the welding site, and the outer wall surface of the third jig member is inclined outward toward the welding site. It is preferable to have a second inclined surface. For this reason, the second and third jig members can be held in contact with the workpiece up to the vicinity of the welding site, and welding can be performed in the vicinity of the outer peripheral portion of the workpiece. Therefore, deformation of the workpiece after welding can be reliably suppressed, and a good welding process is performed.

  Furthermore, the second jig member opens to the inner wall surface and has a first passage for introducing the assist gas into the gap, and the third jig member opens to the outer wall surface to allow the assist gas to pass through the gap. It is preferable to have the 2nd channel | path for introducing into. Thereby, since assist gas is sprayed on a welding site | part, the atmosphere of the said welding site | part can be stabilized. For this reason, the opportunity to be exposed to oxygen is greatly suppressed in the welded part, and defects during welding can be satisfactorily prevented.

  Furthermore, it is preferable that the welded portion is continuous around the outer periphery of the workpiece, and the gap is formed continuously along the welded portion without a seam. Therefore, since seamless welding is performed around the outer periphery of the workpiece, the welding accuracy is improved satisfactorily.

  Moreover, it is preferable that a workpiece | work is provided with the fastening member for fixing a 3rd jig | tool member to a 1st jig | tool member while providing a hole inside a welding part and being inserted in the said hole. Thereby, the inside can be reliably held via the third jig member and the first jig member, and the seamless welding is performed along the outer periphery of the workpiece. It becomes possible.

  The welding jig device further includes a positioning member that is inserted into the gap to position the third jig member with respect to the first jig member, and the positioning member is inclined to the outer wall that is in sliding contact with the first inclined surface. The outer wall inclined surface and the inner wall inclined surface are configured in a wedge shape that is inclined in a direction close to each other toward the welding site. preferable. Therefore, the third jig member can be positioned with high accuracy with respect to the first jig member simply by inserting the positioning member into the gap, and the work positioning operation can be easily and accurately performed.

  Furthermore, the present invention relates to a welding method using a welding jig device for holding a workpiece in which a first plate and a second plate are overlapped and welding the workpiece along a welded portion of an outer peripheral portion of the workpiece. It is.

  The welding jig apparatus includes a first jig member for arranging a workpiece, a second jig member having an opening shape smaller than the outer shape of the workpiece, and a third jig member arranged in the opening portion. It has.

  In this welding method, a work is arranged on the first jig member, and an outer peripheral end portion of the work is sandwiched between the first jig member and the second jig member, and a third jig member Is arranged in the opening, and the third jig member and the first jig member hold the inner side of the outer peripheral end of the workpiece, and the outer wall surface of the third jig member and the first jig member. 2 It has the process of providing the clearance gap which exposes the said welding site | part between the inner wall surfaces which form the said opening part of a jig member, and the process of welding the said welding site | part from the said clearance gap.

  Moreover, it is preferable that this welding method welds a welding site | part, introducing assist gas into a clearance gap. Therefore, since the assist gas is sprayed on the welded part, the atmosphere of the welded part can be stabilized. Thereby, the opportunity to be exposed to oxygen is significantly suppressed in the welded part, and defects during welding can be satisfactorily prevented.

  Furthermore, in this welding method, it is preferable that welding is continuously performed on the welded portion by continuously moving the welding gun along the gap. For this reason, since seamless welding is performed around the outer periphery of the workpiece, the welding accuracy is improved satisfactorily.

  According to the present invention, the outer peripheral end of the workpiece is sandwiched between the first jig member and the second jig member, and the outer peripheral end of the workpiece is clamped by the first jig member and the third jig member. The welding process is performed on the welded part in a state where the inner part is held rather than the part. For this reason, the workpiece | work is hold | maintained favorably via the 1st jig | tool member, the 2nd jig | tool member, and the 3rd jig | tool member in parts other than a welding site | part.

  As a result, even if warping or distortion exists in the workpiece, the welded portion can be formed flat, and the two plates can be welded easily and satisfactorily, and the welding distortion is suppressed and high accuracy is achieved. It is possible to perform the welding process.

It is a principal part disassembled perspective explanatory drawing of the welding jig apparatus which concerns on embodiment of this invention. It is a perspective view of the said jig apparatus for welding. It is the III-III sectional view taken on the line in FIG. 2 of the said jig apparatus for welding. It is a schematic exploded perspective view of a fuel cell in which a separator to be welded by the welding jig device is incorporated. It is a partially exploded perspective view showing the gas flow state of the fuel cell. It is explanatory drawing of the welding process by the said jig apparatus for welding.

  1 to 3 show a welding jig apparatus 10 according to an embodiment of the present invention. The workpieces welded by the welding jig device 10 are, for example, first and second separators 14a and 14b constituting the fuel cell 12, as shown in FIGS.

  The fuel cell 12 is a solid electrolyte fuel cell. For example, an anode electrode 18 and a cathode electrode 20 are provided on both surfaces of an electrolyte (electrolyte plate) 16 made of an oxide ion conductor such as stabilized zirconia. An electrolyte / electrode assembly (MEA) 22 is provided. The electrolyte / electrode assembly 22 is formed in a disc shape, and a barrier layer (not shown) is provided at least on the outer peripheral end surface portion to prevent entry and discharge of the oxidant gas and the fuel gas. Yes.

  In the fuel cell 12, a plurality of, for example, two electrolyte / electrode assemblies 22 are sandwiched between the first and second separators 14a and 14b. The first separator 14a and the second separator 14b are configured by reversing the same-shaped separator structure by 180 ° from each other.

  The first separator 14a includes, for example, a first plate 24a and a second plate 26a configured by press-molding a sheet metal such as stainless steel. The first plate 24a and the second plate 26a are joined to each other by diffusion bonding, resistance seam welding, laser welding, brazing, or the like. In the present embodiment, the first plate 24a and the second plate 26a are joined by YAG laser welding.

  The first plate 24a is formed in a substantially flat plate shape, and includes a fuel gas supply unit 30 in which a fuel gas supply communication hole 28 for supplying fuel gas along the stacking direction (arrow A direction) is formed. First sandwiching portions 34 a and 34 b are integrally provided via two first bridge portions 32 a and 32 b extending outward from the fuel gas supply portion 30.

  The first sandwiching portions 34a and 34b are set to have substantially the same dimensions as the electrolyte / electrode assembly 22, and a plurality of projections 36a having a current collecting function are provided on the surface contacting the electrolyte / electrode assembly 22. 36b is provided. Fuel gas passages 38 a and 38 b for supplying fuel gas along the electrode surface of the anode electrode 18 are formed between the plurality of protrusions 36 a and 36 b and the electrolyte / electrode assembly 22. Fuel gas supply holes 40a and 40b for supplying fuel gas toward the substantially central portion of the anode electrode 18 are formed in the substantially central portions of the first sandwiching portions 34a and 34b.

  The second plate 26a has a fuel gas supply part 42 in which a fuel gas supply communication hole 28 is formed. First sandwiching portions 46a and 46b are integrally provided via two first bridge portions 44a and 44b extending outward from the fuel gas supply portion 42. A circumferential convex portion 48 is provided around the outer periphery of the second plate 26a so as to protrude toward the first plate 24a. A welded portion 49 set on the outer peripheral portion of the first plate 24a is joined to the circumferential convex portion 48. The

  The surfaces of the fuel gas supply unit 42, the first bridge portions 44a and 44b, and the first sandwiching portions 46a and 46b that face the first plate 24a are in contact with the first plate 24a and have a function of preventing collapse against a load in the stacking direction. A plurality of protrusions 56 are formed.

  Fuel gas supply passages 58a and 58b communicating with the fuel gas supply communication hole 28 are formed between the first bridge portions 32a and 44a and between the first bridge portions 32b and 44b. The fuel gas supply passages 58a and 58b communicate with the fuel gas supply holes 40a and 40b via the fuel gas filling chambers 60a and 60b formed between the first holding parts 34a and 46a and between the first holding parts 34b and 46b. To do.

  The second separator 14b is configured in the same shape as the first separator 14a, and includes a first plate 24b and a second plate 26b corresponding to the first plate 24a and the second plate 26a. The first plate 24b and the second plate 26b have oxidant gas supply parts 64 and 66 in which oxidant gas supply communication holes 62 for supplying an oxidant gas along the stacking direction are formed.

  The first plate 24b and the second plate 26b are connected to the second sandwiching portions 72a, 72b, and 74a via two second bridge portions 68a, 68b, and 70a and 70b that protrude outward from the oxidizing gas supply portions 64 and 66, respectively. 74b are integrally provided.

  The second sandwiching portions 72 a and 72 b are set to have substantially the same dimensions as the electrolyte / electrode assembly 22, and a plurality of current collecting functions are provided on the surface in contact with the cathode electrode 20 constituting the electrolyte / electrode assembly 22. Protrusions 75a and 75b are provided. Oxidant gas passages 76 a and 76 b for supplying an oxidant gas along the electrode surface of the cathode electrode 20 are formed between the plurality of protrusions 75 a and 75 b and the electrolyte / electrode assembly 22. Oxidant gas supply holes 78a and 78b for supplying an oxidant gas toward the substantially central part of the cathode electrode 20 are formed in the substantially central parts of the second sandwiching parts 72a and 72b.

  In the second plate 26b, oxidant gas supply passages 80a and 80b communicating with the oxidant gas supply communication hole 62 by joining the first plate 24b are provided between the second bridge portions 68a and 70a and the second bridge. It is formed correspondingly between the portions 68b and 70b. In the second sandwiching portions 74a and 74b, oxidant gas filling chambers 82a and 82b communicating with the oxidant gas supply communication hole 62 through the oxidant gas supply passages 80a and 80b are formed.

  As shown in FIGS. 1 to 3, the welding jig apparatus 10 includes a base member 90 and a first separator 14 a that is a workpiece (the second separator 14 b is the same, and only the first separator 14 a will be described below. A second jig member 96 in which an opening 94 having an opening shape smaller than the outer shape of the first separator 14a is formed, and the opening 94. And a third jig member 98 disposed on the surface.

  A first jig member 92 is placed on the base member 90, and the first jig member 92 is formed with a recess 100 having the shape of the first separator 14a on the upper surface side thereof. The first jig member 92 is formed with a through hole 102 corresponding to the fuel gas supply communication hole 28 of the first separator 14 a, while the base member 90 is screwed coaxially with the through hole 102. A hole 104 is formed.

  Water cooling passages 106 a and 106 b for supplying cooling water are formed on both sides of the first jig member 92. The water cooling passages 106a and 106b are formed in a substantially U shape in the first jig member 92, and are arranged corresponding to the shapes of the first clamping portions 34a and 46a and 34b and 46b of the first separator 14a. .

  The second jig member 96 holds the first jig member 92 and the outer peripheral end of the first separator 14a in a state where the first separator 14a is disposed in the recess 100 of the first jig member 92. As shown in FIG. 3, the second jig member 96 has a first inclined surface 97 a whose inner wall surface forming the opening 94 is inclined inward toward the welding site 49.

  A first passage 108 that opens to the first inclined surface 97a and introduces assist gas (for example, an inert gas such as argon gas) toward a gap that will be described later is formed in a side portion of the second jig member 96. Shaped. A predetermined number of first passages 108 are provided corresponding to the openings 94.

  The third jig member 98 is disposed in the opening 94 and holds the inner side of the first jig member 92 and the outer peripheral ends of the first separator 14a, and also forms an inner wall that forms the opening 94 with the outer wall surface. A gap 110 for exposing the welded portion 49 is provided between the wall surface. On the outer wall surface of the third jig member 98, a second inclined surface 97b that is inclined outward toward the welded portion 49 is provided. The third jig member 98 opens to the second inclined surface 97b and has a predetermined number of second passages 112 for introducing the assist gas into the gap 110.

  A through hole 114 corresponding to the fuel gas supply communication hole 28 of the first separator 14 a is formed in the third jig member 98. The third jig member 98 is fixed to the base member 90 via the fastening member 116. The fastening member 116 has a fixing screw 118.

  The fixing screw 118 passes through the through hole 114 of the third jig member 98, the opening 94 of the second jig member 96, and the through hole 102 of the first jig member 92, and the screw hole portion of the base member 90. Screwed into 104. The fixing screw 118 is provided on the arm member 120, and the arm member 120 is provided with screw members 122 a and 122 b that are in contact with substantially the center of the respective disk portions 98 a and 98 b of the third jig member 98.

  The welding jig device 10 is inserted into the gap 110 between the second jig member 96 and the third jig member 98 to position the third jig member 98 with respect to the first jig member 92. A ring member (positioning member) 124 is provided. As shown in FIG. 3, the positioning ring member 124 has an outer wall inclined surface 126a that is in sliding contact with the first inclined surface 97a, and an inner wall inclined surface 126b that is in sliding contact with the second inclined surface 97b. The outer wall inclined surface 126a and the inner wall inclined surface 126b are configured in a wedge shape that is inclined in a direction approaching each other toward the welding site 49.

  The base member 90, the first jig member 92, and the second jig member 96 are fixed to each other via a plurality of fixtures 128 (including screws not shown).

  A welding method for welding the first separator 14a using the welding jig apparatus 10 configured as described above will be described below.

  First, the first jig member 92 is fixed on the base member 90, and the first plate 24a and the second plate 26a overlap each other in the recess 100 formed on the upper surface of the first jig member 92. The first separator 14a thus arranged is disposed. As shown in FIG. 4, the first plate 24a and the second plate 26a are pre-pressed, and a plurality of protrusions 36a and 36b are formed on the first plate 24a. A plurality of protrusions 56 are formed on the second plate 26a.

  Next, the second jig member 96 is placed on the first jig member 92 with the first separator 14a interposed. For this reason, as shown in FIG. 6, the first jig member 92 and the second jig member 96 sandwich the outer peripheral end portion of the first separator 14 a. Further, as shown in FIGS. 2 and 3, the third jig member 98 is disposed in the opening 94 of the second jig member 96, and the third jig member 98 is interposed via the fastening member 116. The base member 90 is fixed.

  Here, before the third jig member 98 is tightened by the tightening member 116, the third jig member 98 is positioned via the positioning ring member 124. The positioning ring member 124 is inserted into a gap 110 formed between the second jig member 96 and the third jig member 98.

  As shown in FIG. 3, the outer wall inclined surface 126a of the positioning ring member 124 is in sliding contact with the first inclined surface 97a, while the inner wall inclined surface 126b of the positioning ring member 124 is in sliding contact with the second inclined surface 97b. Therefore, the third jig member 98 is positioned in the opening 94 of the second jig member 96 under the wedge action of the outer wall inclined surface 126a and the inner wall inclined surface 126b. In the positioning ring member 124, after positioning the disk part 98a of the third jig member 98, the disk part 98b is similarly subjected to positioning processing.

  Thus, after the third jig member 98 is positioned, the fixing screw 118 that constitutes the fastening member 116 is screwed into the screw hole 104 of the base member 90. For this reason, the third jig member 98 holds the second jig member 96 inward from the outer peripheral end of the first separator 14a. In the third jig member 98, the disk portions 98a and 98b are pressed and held by the screw members 122a and 122b, and the first separator 14a has a load equivalent to the tightening load applied when the fuel cell stack is stacked. Has been granted.

  Therefore, the cooling water is circulated and supplied to each of the water cooling passages 106 a and 106 of the first jig member 92. Meanwhile, an assist gas (for example, argon gas) is supplied to the first passage 108 of the second jig member 96 and the second passage 112 of the third jig member 98, and the assist gas passes through the first inclined surface 97a. And it is introduced into the gap 110 from the second inclined surface 97b.

  In this state, as shown in FIG. 6, the welding gun 130 continuously moves along the gap 110 to perform a welding operation on the welding portion 49 of the first separator 14 a. Here, the welded portion 49 of the separator 14 a is exposed to the outside in a seamless state, and seamless welding can be performed on the welded portion 49 by the welding gun 130.

  In this case, according to the present embodiment, the first jig member 92 and the second jig member 96 sandwich the outer peripheral end portion of the separator 14a, and the first jig member 92 and the third jig. The laser welding process by the welding gun 130 is performed on the welding portion 49 in a state where the inner side of the first separator 14a is held by the member 98 from the outer peripheral end portion. For this reason, the first plate 24a and the second plate 26a constituting the first separator 14a are not welded with the first jig member 92, the second jig member 96, and the third jig. It is held well via the member 98.

  Thereby, even if the 1st plate 24a and the 2nd plate 26b have curvature and distortion by press molding, the welding site | part 49 can be formed flatly. Therefore, the first plate 24a and the second plate 26a can be easily and satisfactorily welded to each other, and an effect of suppressing welding distortion and performing a highly accurate welding process can be obtained.

  Further, as shown in FIG. 3, the inner wall surface of the second jig member 96 is provided with a first inclined surface 97 a that is inclined inward toward the welded portion 49, and an outer side of the third jig member 98. The wall surface is provided with a second inclined surface 97b that is inclined outward toward the welded portion 49.

  Therefore, the second jig member 96 and the third jig member 98 can be held in contact with the first separator 14a up to the vicinity of the welded portion 49, and the laser is provided near the outer periphery of the first separator 14a. It becomes possible to perform welding. Therefore, deformation of the first separator 14a after welding can be reliably suppressed, and a good welding process is performed.

  Further, the second jig member 96 has an opening in the first inclined surface 97a and has a first passage 108 for introducing the assist gas into the gap 110, and the third jig member 98 has the second inclined surface 97b. And has a second passage 112 for introducing the assist gas into the gap 110. Thereby, since assist gas is sprayed on the welding part 49, the atmosphere of the said welding part 49 can be stabilized. For this reason, the opportunity to be exposed to oxygen is greatly suppressed in the welded portion 49, and defects during welding can be satisfactorily suppressed.

  Furthermore, the welded portion 49 circulates around the outer peripheral portion of the first separator 14 a and continues continuously, and the gap 110 is formed continuously along the welded portion 49 without a joint. Therefore, only by moving the welding gun 130 along the gap 110, seamless welding is performed around the outer periphery of the first separator 14a, and welding accuracy can be easily improved.

  Further, the first separator 14 a is provided with a fuel gas supply communication hole 28 inside the welded portion 49. The fixing screw 118 constituting the fastening member 116 fixes the third jig member 98 to the first jig member 92 as a fastening tool inserted into the fuel gas supply communication hole 28. Thus, the inner side of the first separator 14a can be reliably held via the third jig member 98 and the first jig member 92, and the outer circumference of the first separator 14a can be held. It is possible to easily perform seamless welding around the part.

  Further, the positioning ring member 124 has an outer wall inclined surface 126a that is in sliding contact with the first inclined surface 97a, and an inner wall inclined surface 126b that is in sliding contact with the second inclined surface 97b. At that time, the outer wall inclined surface 126 a and the inner wall inclined surface 126 b are formed in a wedge shape that is inclined in a direction approaching each other toward the welding site 49. Therefore, the third jig member 98 can be positioned with high accuracy with respect to the first jig member 92 only by inserting the positioning ring member 124 into the gap 110, and the first separator 14a is positioned. Has the advantage of being easily and accurately performed.

  In addition, although this embodiment demonstrated using the separator which has two clamping parts as a workpiece | work, it is not limited to this. For example, the present invention can be applied to a separator in which three, four, or five or more sandwiching portions are concentrically arranged around a single reaction gas supply communication hole.

DESCRIPTION OF SYMBOLS 10 ... Jig apparatus for welding 12 ... Fuel cell 14a, 14b ... Separator 24a, 26a ... Plate 28 ... Fuel gas supply communication hole 30, 42 ... Fuel gas supply part 32a, 32b, 44a, 44b, 68a, 68b, 70a, 70b: Bridge portions 34a, 34b, 46a, 46b, 72a, 72b, 74a, 74b ... Nipping portions 36a, 36b, 56, 75a, 75b ... Projections 49 ... Welded parts 90 ... Base members 92, 96, 98 ... Tool member 94 ... Openings 97a and 97b ... Inclined surfaces 102 and 114 ... Through holes 104 ... Screw holes 106a and 106b ... Water-cooling passages 108 and 112 ... Passage 110 ... Gap 116 ... Tightening member 118 ... Fixing screws 122a and 122b ... Screw member 124 ... Positioning ring member 126a ... Outer wall inclined surface 126b ... Inner wall inclined surface

Claims (9)

A welding jig apparatus for holding a workpiece in which a first plate and a second plate are overlapped and welding along a welded portion of an outer peripheral portion of the workpiece,
A first jig member for arranging the workpiece;
An opening corresponding to the shape of the workpiece is formed, and the first jig member and a second jig member that sandwiches the outer peripheral end of the workpiece,
The first jig member and an inner wall surface that forms the opening of the second jig member and is arranged to hold the inner side of the first jig member and the outer peripheral end of the workpiece. A third jig member for providing a gap for exposing the welded portion therebetween,
A welding jig apparatus comprising: The welding jig device according to claim 1, wherein the inner wall surface of the second jig member has a first inclined surface inclined inward toward the welding site,
The welding jig apparatus, wherein the outer wall surface of the third jig member has a second inclined surface that is inclined outward toward the welding site. The welding jig device according to claim 1 or 2, wherein the second jig member has a first passage that opens into the inner wall surface and introduces assist gas into the gap.
The welding jig apparatus, wherein the third jig member has a second passage that opens to the outer wall surface and introduces the assist gas into the gap. The welding jig apparatus according to any one of claims 1 to 3, wherein the welding portion circulates continuously around the outer peripheral portion of the workpiece,
The welding jig device characterized in that the gap is formed continuously along the welding site without a seam. The welding jig device according to any one of claims 1 to 4, wherein the workpiece is provided with a hole inside the welding site,
A welding jig device comprising a fastening member inserted into the hole for fixing the third jig member to the first jig member. The welding jig apparatus according to any one of claims 2 to 5, further comprising a positioning member that is inserted into the gap and positions the third jig member with respect to the first jig member.
The positioning member includes an outer wall inclined surface slidably contacting the first inclined surface;
An inner wall inclined surface in sliding contact with the second inclined surface;
And having
The welding jig apparatus characterized in that the outer wall inclined surface and the inner wall inclined surface are formed in a wedge shape in a cross section that is inclined in a direction close to each other toward the welding site. A welding method for welding along a welding site set on an outer peripheral portion of the workpiece using a welding jig apparatus that holds a workpiece in which the first plate and the second plate are overlapped,
The welding jig device includes a first jig member for arranging the workpiece, a second jig member having an opening shape smaller than the outer shape of the workpiece, and a third jig arranged in the opening. Comprising ingredients,
The welding method includes the step of placing the workpiece on the first jig member and sandwiching an outer peripheral end portion of the workpiece by the first jig member and the second jig member;
The third jig member is arranged in the opening, and the third jig member and the first jig member hold the inner side of the outer peripheral end of the workpiece by the third jig member and the third jig. Providing a gap for exposing the welded portion between an outer wall surface of the member and an inner wall surface forming the opening of the second jig member;
Welding the weld site from the gap;
A welding method characterized by comprising:   The welding method according to claim 7, wherein the welding portion is welded while introducing an assist gas into the gap.   9. The welding method according to claim 7 or 8, wherein welding is performed continuously and seamlessly on the welding site by moving a welding gun continuously along the gap.

Images