JP2003136257A - Method for manufacturing curved surface structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a structure having a curved surface highly precisely at a low cost. SOLUTION: In the structure constituted of a plurality of large blocks, each block 50 is composed of a curved face plate 51 and ribs 55 which are provided on the outer periphery or the like of one surface of the face plate 51. The blocks are further divided into several sub-blocks, which are also composed of the face plate 51 and the ribs 55 similar to the large blocks. The sub-blocks are assembled by friction stir welding to form the large blocks. Then, the plurality of large blocks are placed on a frame, and the outer peripheral rib end-faces of the adjacent large blocks are brought into contact with or brought close to each other with the face plates of the large blocks welded to each other, and also with the ribs welded to each other. Consequently, the structure can be manufactured highly precisely at a low cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of connecting a plurality of curved plates to manufacture a relatively large structure. For example, it is suitable for manufacturing a portion having a three-dimensional curved surface in order to improve fluid characteristics such as a leading portion of a railroad car, an aircraft, a hull, and the like.

[0002]

2. Description of the Related Art The leading portion of the leading vehicle of a railway vehicle has a three-dimensional curved surface from the viewpoint of air resistance and design. It also requires a fairly complex curved surface. As a method for manufacturing such a curved surface structure, there is JP-A-2000-301365. This is an individual block that constitutes the leading portion of the leading car, the plate is pressed to manufacture a curved plate, and then one surface of the curved plate is cut to provide grid-shaped ribs.

Japanese Unexamined Patent Publication No. 9-309164 (EP 0
Friction stir welding is used as a welding means, as described in (797043 A2). It has the feature of little joint deformation and dimensional change.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
No. 01365 manufactures a curved plate by pressing a plate, then cuts one surface of the curved plate and joins blocks provided with ribs by welding or friction stir welding to assemble the structure. . However, it is difficult to press-form a curved plate with a complicated large block including a tight curved portion, and the forming accuracy is lowered, so the thickness of the material plate is increased to secure a cutting allowance. Therefore, the material cost increases and the processing time increases. Further, it is difficult to center and position the material in cutting a complicated curved surface of a large-sized part. Moreover, positioning of a tool of a large-sized processing machine takes time. As a result, there has been a problem in that the processing of large blocks becomes inefficient.

On the other hand, although friction stir welding has been described as a means for joining the blocks, a convex portion is provided on the outer surface of the face plate in order to prevent depression of the joining portion. For this reason, the plate thickness of the material becomes large, and it is necessary to perform processing for providing the convex portion.

The present invention relates to a method and structure for manufacturing a curved surface structure, and an object thereof is to provide a relatively large curved surface structure such as a railway vehicle at low cost with high accuracy.

[0007]

The above object is to provide a structure composed of a plurality of large blocks, in which a face plate has a curved surface, and a rib is provided on a block outer peripheral portion of one face of the face plate,
A plurality of large blocks are further divided into several small blocks, and the small blocks have ribs provided on the outer peripheral portion of the small blocks on one surface of the face plate, as in the large blocks. Assemble by friction stir welding,
A large block, and the plurality of large blocks are placed on a stand,
At this time, the outer peripheral rib end surfaces of the adjacent large blocks are brought into contact with or close to the end portions of the ribs of the adjacent blocks, the face plates of the plurality of large blocks are joined together, and the ribs are joined together. Can be achieved by

The small block is manufactured, for example, by bending a plate into a curved surface, cutting one surface of the plate, providing a rib, and making a hole.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A case in which the present invention is applied to a head portion of a rail car will be described below with reference to FIGS. The shape of the friction stir welding part is schematically shown.

In FIG. 1, the size of the block 50 and the like with respect to the size of the vehicle are schematically shown. The block 50 is a plate made of an aluminum alloy.

As shown in FIG. 4, the leading portions S1 and S of the vehicle body
2 and S3 have a three-dimensional curved surface that is bent along the longitudinal direction and the width direction of the vehicle body. There is a driver's seat window C in the portion S3. The portion S3 often has a curved surface that further projects from the curved surface. Therefore, the portion S3 often has a complicated curved surface. Part S4 is a guest room part, and the doorway D1,
D2, there is a window W. Since the outer surface of this portion is linear along the longitudinal direction of the vehicle body, it has the conventional configuration. The leading vehicle is composed of an underframe 100 that constitutes the floor, a curved surface portion S3 mounted on the underframe 100, a straight portion S4, and curved surface portions S2 and S3 installed at the tip of the curved surface portion S3.

The embodiment shown in FIGS. 1 to 14 is applied to a relatively large curved surface portion (a portion where the height of the vehicle body is high) S3. The curved surface portions S1 and S2 can be similarly manufactured. Curved surface S3
Is configured by connecting a plurality of large blocks 50 in the longitudinal direction and the width direction of the vehicle.

As shown in FIG. 3 when the large block 50 is viewed from the inside of the vehicle, and in FIG. 2 where the blocks 50 are connected to each other, the large block 50 includes a face plate 51 forming an outer surface of the vehicle and a plurality of protrusions on the inner surface of the face plate 51. And ribs 55. The rib 55 is
It comprises a plurality of vertical ribs along the vertical direction (vertical direction) of the vehicle body and a plurality of horizontal ribs along the horizontal direction (horizontal direction). The ribs 55 are connected to each other to form a grid. The protrusion margin of the rib 55 is constant. Each large block has ribs 5 at the end
Have five.

The end of the face plate 51 of one large block 50 is abutted against the rib 55 of the end of the other large block 50. The large blocks 50, 50 are welded W1 from the outside of the vehicle at this portion. A welding groove is provided at the welded portion W1. Thus, the upper end of the sebid is located on the extension line of the outer surface of the face plate 51. After welding, the outer surface of the weld bead is cut so that it is located on the extension line of the outer surface of the face plate 51.
The ribs 55, 55 at the ends are welded W2 from the inside of the vehicle.

The lower end of the portion S3 including the plurality of blocks 50 is mounted on the underframe 100 of the vehicle body. The same applies to the other portion S4.

The head portion of the head car of the railway vehicle becomes lower in height and becomes narrower toward the head. Further, the surface shape is also a complicated curved surface from an aerodynamic viewpoint. Therefore, the block 50 is often a trapezoidal curved plate.

The large block 50 is composed of small blocks 50A, 50B, 50C and 50D as shown in FIG. When divided into small blocks in this way, the tight curved surface portion 5
0A and 50B and gentle curved surface portions 50C and 50D, and the size is reduced.

As a result, the molding accuracy is improved, the thickness of the material plate is reduced, and the material cost and the molding processing time are reduced. Further, the centering and positioning of the material at the time of cutting can be facilitated, and the positioning of the tool can be performed in a short time by a small-sized processing machine, which enables highly efficient processing.

Small blocks 50A, 50B, 50C, 50
D are combined with each other, and each boundary line f1,
F2, f3, and f4 are joined by friction stir welding.

In FIG. 6, the large block 50 is composed of two small blocks 50AB and 50CD. f0 is a boundary line. FIG. 7 shows a state where the small block 50AB is viewed from the rib side. The tightness of the boundary line f is determined by the angle θ formed by the tangent line in each cross section. When θ becomes approximately 120 degrees or less, the block is divided.

A combination and a positioning method for friction stir welding small blocks will be described with reference to FIG.

The outer peripheral ribs 55, 55 of the small blocks 50A, 50C respectively have a plurality of holes h. The pair of holes h are provided at the same distance from the outer surface of the face plate 51. Ribs 5 abutted against each other in the plurality of holes h
The bolts and nuts 61 and 62 are connected to each other.
This joint portion becomes the friction stir welding portion f. Hole h and bolt 6
The difference in the diameter of the shank of No. 1 is about 0.3 mm. As a result, the ribs 55, 55 can be brought into close contact with each other and a step required on the outer surface of the face plate 51 can be formed.

After the joining, the ribs 55, 55 immediately below the friction stir welding part f are supported by the jack base 71. Further, the ribs 55, 55 at the outer ends of the blocks are placed on the jack stands 72, 72. In this state, a presser foot 74 is put in the hole h of the rib 55 at the end and is fastened to the mount with bolts 75. With these, the large force of friction stir welding can be stably supported.

FIG. 9 shows a second positioning method when the small blocks are friction stir welded together. As described above, the small blocks are temporarily fixed to each other with the bolts and nuts 61 and 62, and then mounted on the jack stands 71 and 72. In this state, align the bolts so that there is no step on the outer surface of the face plate of the friction stir welding part of the blocks 50A and 50C,
The nuts 61 and 62 are connected. At the same time, the presser foot 74 inserted in the plural holes h is fixed by the bolt 75. Positioning is performed by bolts / nuts 61, 62, 74, jack stands 71, 72, and the like.

FIG. 10 shows the shape of the friction stir welding part and the tool 8
The relationship with 0 is shown. The rotary tool 80 has a small diameter portion 82 at the tip of the large diameter portion 81. The large diameter portion 81 and the small diameter portion 82 in the vicinity of the small diameter portion 82 are inserted into the abutting portions of the members to be joined, and the boundary line f (f0, f0,
f1, f2, f3, F4), and it joins. Friction stir welding is performed in the state shown in FIGS. The ribs 55, 55 of the friction stir welding portion are bolts and nuts 61, 6
Are joined by two.

The large diameter portion 81 is inserted into the abutting portion by a depth g. As for the insertion margin g, the radius of curvature of the joint portion and the gap of the butted portion are considered. The small diameter portion 82 is a screw.

The distance t2 from the vicinity of the tip of the small diameter portion 82 to the rear side of the rib 55 or the face plate 51, in particular, the rib 55 and the face plate 5.
The distance t2 from the vicinity of the connection portion with 1 to the small diameter portion 82 is set to a thickness that does not swell due to the force during friction stir welding. For example, the radius R of the connecting portion may be increased or may be linear. Alternatively, the connection portion is recessed toward the friction stir welding portion side, but is projected to the opposite side. The total width of the two ribs 55, 55 of the friction stir welding portion is the diameter d of the large diameter portion 81.
However, it may be smaller. The thickness of the rib 55 is
There is no swelling, and the rib 5 is applied by the force during friction stir welding.
The thickness is set so that 5,55 do not buckle.

When friction stir welding is performed, a groove having a depth of the insertion margin g is formed in the friction stir welding portion. Fill this with putty and paint. Incidentally, it is possible to provide a convex portion projecting to the outer surface in consideration of the depth of the groove g, and after friction stir welding, the convex portion can be removed by cutting. This is known.

After friction stir welding, the rib 5 at the abutting portion
Weld the ends of 5,55. Welding may be intermittent welding. Then remove the bolts and nuts 61 and 62. Can be lightweight.

In FIG. 11, the ends of the ribs 55, 55 are friction stir welded. 90 indicates a friction stir welding part. The butt portion on the side of the face plate 51 is welded in advance. 10
Reference numeral 1 indicates a welded portion. Since this welding 101 is intermittent, heat input is small and deformation and dimensional change are small.

Such small blocks 50A, 50B, 50
The processing and assembling procedure of the C, 50D and the large block 50 will be described with reference to FIG.

First, the small blocks 50A, 50B, 50
C and 50D are manufactured in the same manner as the above-mentioned known example (step S100). That is, the plate is cut, pressed to form a curved surface plate having a predetermined curved surface, and annealed. Next, the curved plate is cut with a 5-axis machining center or the like to form ribs, and the face plate is finished and then trimmed to form a block shape, and the rib end faces are finished and holes are formed. by this,
An outer surface of a face plate having an accurate curved surface and a rib structure having high rigidity with accurate dimensional accuracy can be obtained. Further, since the trimming and the drilling are performed by NC processing, a curved plate (small block) having an accurate outer shape and assembly standard can be obtained.

Next, the small blocks 50A and 50B are placed on the contact machine (step S200). The joining machine uses the above-mentioned 5-axis machining center or a machine capable of simultaneously moving 5 or more axes. The small blocks are positioned and fixed, and friction stir welding is performed (steps S210 and S220). Positioning and fixing and friction stir welding are performed as described above. The small blocks 50C and 50D work similarly. Next, the blocks 50A and 50B and the blocks 50C and 50D are similarly assembled by friction stir welding.

After friction stir welding, the rib side is welded to complete the large block 50 (step S230). Welding uses arc welding such as MIG welding or TIG welding.

Next, a plurality of large blocks 50 that are mounted along the outer surface of the vehicle are placed with their ribs facing downward (step S260). Each large block is placed on a frame, and as described above, a rod-shaped metal fitting is attached to the hole h of the outer peripheral rib 56 of the adjacent blocks, and the block is positioned within the range of the difference between the hole diameter and the rod diameter. If the difference between the hole diameter and the rod diameter is 1 mm, the step on the outer surface is 1 mm at the maximum.
Can be limited to Furthermore, by reducing the difference between the hole diameter and the rod diameter, or by tapering the tip portion of the rod-shaped metal fitting, the stepped amount on the outer surface can be reduced.

Next, the boundary portion (groove) on the outer surface of the large block is welded (step S270). Welding uses arc welding such as MIG welding or TIG welding, or friction stir welding.

Next, the rib ends of the boundaries between the large blocks are welded (step S280).

Next, the structure is placed on the underframe 100 and bonded (step S290). The coupling method is the same as the above step.

Next, the outer surface is painted. It is usually applied after joining with the underframe, but in some cases it is painted before joining with the underframe.

As a result, a plurality of blocks can be accurately and easily assembled, and a structure having an airtight inner and outer surface can be obtained. The precision of the structure is good, so the finish of the painting is good and the appearance curved surface with good appearance is obtained.

The technical scope of the present invention is not limited to the wording described in each claim of the claims or the wording described in the section of means for solving the problem, and those skilled in the art can easily replace it. It extends to a range. For example, the case where the shape of the rib is partially different is also included.

[0042]

According to the present invention, a simplified and miniaturized small panel block is assembled by friction stir welding to rationally form a high-precision large block, so that a vehicle or structure can be manufactured accurately and inexpensively. can do.

[Brief description of drawings]

FIG. 1 is a perspective view of a head portion of an embodiment of the present invention.

2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a structural diagram of a block.

FIG. 4 is a side view of the vehicle body of FIG.

FIG. 5 is a first example of an assembly diagram of a large block.

FIG. 6 is a second example of an assembly diagram of a large block.

FIG. 7 is a diagram illustrating a shape of a small block.

FIG. 8 is a first example of an assembly diagram of small blocks.

FIG. 9 is a second example of an assembly diagram of small blocks.

FIG. 10 is a first example of a joined state diagram of block assembly.

FIG. 11 is a second example of a block joining assembly diagram.

FIG. 12 is a flowchart illustrating a block manufacturing method.

[Explanation of symbols]

50 ... Large block, 50A, 50B, 50C, 50D,
50AB, 50CD ... Small block, 51 ... Face plate, 55 ...
Ribs, 56 ... Outer circumference ribs, 61, 75 ... Bolts, 62 ... Nuts, 71, 72 ... Jack stand, 74 ... Presser foot, 80
... friction stir welding tool, 81 ... pin portion, 82 ... shoulder portion, 90 ... friction stir welding portion, 91 ... welding recess portion, 92 ...
Filling putty, 100 ... Underframe, 101 ... Welding.

Claims (7)

[Claims] 1. A structure composed of a plurality of large blocks, wherein the large blocks are composed of a plurality of small blocks, the small blocks being a curved face plate and an outer peripheral portion provided on one surface of the face plate. A plurality of ribs, and the ribs are provided on the outer peripheral portion of the large block, and the small blocks are combined with the rib portions of the outer peripheral portions adjacent to each other, and one side of the combination line is continuous friction stir welding, the other The side is assembled by intermittent or continuous welding to form a large block, and the plurality of large blocks are mounted on a gantry. At this time, the outer peripheral rib end faces of the adjacent large blocks are the end portions of the ribs of the adjacent blocks. The method of manufacturing a curved surface structure, wherein the face plates of the plurality of large blocks are joined to each other and the ribs are joined to each other. 2. The method for manufacturing a curved surface structure according to claim 1, wherein the small blocks are combined, the face plate side is friction stir welded, and the rib side is welded to form a large block. Method for manufacturing curved structure. 3. The method for manufacturing a curved surface structure according to claim 1 or 2, wherein a plurality of holes of opposing ribs are provided at the same coordinate position in the outer peripheral ribs of the plurality of small blocks. The small block of is placed on a support base, at this time, the dividing line rib end faces of the adjacent small blocks are brought into contact with or close to each other, the rod-shaped metal fittings are put in the holes of the plurality of children to align the outer surface of the face plate, Further, the rib is supported by a support base, and thereafter, the boundary line portion of the outer surface of the face plate of the small block is friction stir welded. 4. The method for manufacturing a curved surface structure according to claim 1, wherein the plurality of small blocks are placed on a support base, and at this time, the adjacent small blocks are supported by a rib immediately below (nearest to) a joint portion. Receiving with a stand, aligning the outer surface of the face plate, inserting rod-shaped metal fittings into the holes of the plurality of pieces, and tightening with screws,
A method for manufacturing a curved surface structure, characterized in that the end faces of the dividing line ribs are brought into contact with or close to each other, and thereafter, the boundary line portion of the outer surface of the face plate of the small block is friction stir welded. 5. The method for manufacturing a curved structure according to claim 1, wherein the abutting thickness of the face plate roots of the ribs of the adjacent small blocks is larger than the shoulder diameter of the friction stir welding tool. A method of manufacturing a curved surface structure, characterized in that friction stir welding is performed without providing a convex portion on a boundary portion of the outer surface of the face plate of the block, and the joint recess is not exposed on the single face plate portion. 6. The method for producing a curved surface structure according to claim 5, wherein the joining recess of the joining line due to friction stir welding is filled with putty and then painted. 7. The method of manufacturing a curved surface structure according to claim 1, wherein the small blocks are combined together, the rib side is friction stir welded, and the face plate side is welded to form a large block. Method for manufacturing curved structure.