Welded structure of frame

Abstract

To provide a technology capable of preventing a frame from being damaged.SOLUTION: The welded structure of the frame includes an end portion welded portion formed by welding a region extending over the first frame and the second frame at an end portion of at least one of the first frame and the second frame having a rib connected to two surfaces facing each other, and a rib welded portion formed by welding the first frame and the second frame along the rib.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a welded structure for a frame. [Background technology]

[0002] Conventionally, a welded frame structure has been known in which a region spanning a cylindrical first frame and a second frame that is overlapped and in contact with the first frame to cover the first frame is welded together (Patent Document 1). In this technology, a rib is formed on the first frame that protrudes from the outside where the second frame is located to the inside, opposite the second frame. This rib improves the strength of the welded frame structure. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-13747 Summary of the Invention [Problem to be solved by the invention]

[0004] Forces generated by vibrations and other factors are transmitted to the entire frame via the ribs. Therefore, the smaller the welded area of ​​the ribs, the more stress is concentrated. If stress is concentrated on the ribs, cracks may form in the welded areas of the ribs, which could damage the frame. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] According to one embodiment of the present disclosure, there is provided a welded structure for a frame. The welded structure for a frame includes: a first frame having ribs connected to two opposing surfaces; and a second frame overlapping the first frame. The first frame and the second frame are welded at at least one end of the first frame by welding a region spanning the first frame and the second frame; and a rib weld formed by welding the first frame and the second frame along the rib. The weld width of the rib weld is 80% or more of the thickness of the thinner of the first and second frames. According to this embodiment, the welded structure includes a rib weld formed by welding the first frame and the second frame along the rib. This embodiment can increase the weld area of ​​the rib, thereby reducing stress concentration on the rib. This can prevent damage to the frame due to cracks or the like occurring in the rib weld. The present disclosure can be realized in various forms other than the above-described welded structure of a frame, such as a frame welding method, a welding device for welding a frame, a control method for a welding device, a computer program for realizing the control method, and a non-transitory recording medium on which the computer program is recorded. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a diagram showing the configuration of a frame structure. [Figure 2] FIG. 3 is a diagram showing a welded structure between a first frame and a second frame. [Figure 3] FIG. 4 is a diagram for explaining the welding width of a rib weld portion. DETAILED DESCRIPTION OF THE INVENTION

[0008] A. First embodiment: FIG. 1 is a diagram showing the configuration of a frame structure 100. FIG. 1 shows a cross section II of the frame structure 100 in FIG. 2, which will be described later. The frame structure 100 is formed by welding a first frame 10 and a second frame 20 together. The frame structure 100 is, for example, a cylinder head. In this case, the first frame 10 and the second frame 20 are each, for example, an aluminum extrusion. Note that the use of the frame structure 100 and the materials and molding methods of the frames 10, 20 are not limited to those described above.

[0009] The first frame 10 has a first opposing surface 11, a rib connecting surface 12 that is the surface opposite the first opposing surface 11, and a rib 14 that is connected to two opposing surfaces 121, 122 of the rib connecting surface 12. In this embodiment, the first frame 10 is a member having a main body 13 that is a rectangular tube with a constant thickness t1, and a rib 14 that has the same thickness t1 as the main body 13. In other words, the cross-sectional shape of the main body 13 is a rectangular closed cross-sectional shape. The first opposing surface 11 is formed by the outer peripheral surface of the main body 13. The rib connecting surface 12 is formed by the inner peripheral surface of the main body 13. The rib 14 bridges the first connecting surface 121 and the second connecting surface 122 of the rib connecting surface 12 so as to divide the internal space SP formed by the rib connecting surface 12.

[0010] The second frame 20 is superimposed on the first frame 10. The second frame 20 has a second opposing surface 21 facing the first opposing surface 11, a base surface 22 opposite the second opposing surface 21, and a slit 27 formed to penetrate the second opposing surface 21 and the base surface 22 at a position facing the rib 14. In this embodiment, the second frame 20 is a rectangular tubular member having a constant thickness t2. In other words, the cross-sectional shape of the second frame 20 is a rectangular closed cross-sectional shape. The inner diameter D2 of the second frame 20 is larger than the inner diameter D1 of the first frame 10. As a result, the second frame 20 is disposed outward of the first frame 10 so as to cover the first frame 10. The second opposing surface 21 is formed by the inner peripheral surface of the second frame 20. The base surface 22 is formed by the outer peripheral surface of the second frame 20.

[0011] 2 is a diagram showing a welded structure 40 between the first frame 10 and the second frame 20. The welded structure 40 includes an end weld 41 and a rib weld .

[0012] The end weld 41 is formed by welding a region that straddles the first frame 10 and the second frame 20 at at least one of the end 15, 25 of the first frame 10 and the end 25 of the second frame 20. In this embodiment, the end weld 41 is formed by welding a region that straddles the first opposing surface 11 of the first frame 10 and the base surface 22 of the second frame 20 at the end 25 of the second frame 20.

[0013] The rib weld 42 is formed by welding the first frame 10 and the second frame 20 together along the rib 14. In this embodiment, the rib weld 42 is formed by welding the first frame 10 and the second frame 20 together parallel to the rib 14, from the base surface 22 of the second frame 20 toward the rib 14 through the slit 27. The rib weld 42 also intersects with the end weld 41.

[0014] The weld width W of the rib weld 42 is 80% or more of the thicknesses t1 and t2 of the first frame 10 and the second frame 20, whichever has the smaller thickness t1 or t2. In this embodiment, the thickness t1 of the first frame 10 is smaller than the thickness t2 of the second frame 20. Therefore, the weld width W of the rib weld 42 is 80% or more of the thickness t1 of the first frame 10. For example, if the thickness t1 of the first frame 10 is 3.0 mm, the weld width W of the rib weld 42 is 2.4 mm or more. Note that the thickness t2 of the second frame 20 may be smaller than the thickness t1 of the first frame 10. If the thickness t2 of the second frame 20 is smaller than the thickness t1 of the first frame 10, the weld width W of the rib weld 42 is 80% or more of the thickness t2 of the second frame 20. Furthermore, the thickness t1 of the first frame 10 and the thickness t2 of the second frame 20 may be the same. When the thickness t1 of the first frame 10 and the thickness t2 of the second frame 20 are the same, the weld width W of the rib weld 42 is 80% or more of the thickness t1 of the first frame 10 and the thickness t2 of the second frame 20.

[0015] FIG. 3 is a diagram illustrating the weld width W of the rib weld 42. Each view in FIG. 3 shows an enlarged view of region R in FIG. 1. The weld width W of the rib weld 42 is a dimension of the rib weld 42 that determines the strength of the rib weld 42. The weld width W of the rib weld 42 is the width along the thickness direction TD of the rib 14 and is the minimum width of the contact surface 420 of the rib weld 42 that spans the first frame 10 and the second frame 20. As shown in FIG. 1, when the second frame 20 is overlapped on the first frame 10 in contact with the first frame 10, the weld width W of the rib weld 42 is a first width W1, which is the minimum width at the contact surface 420. As shown in FIG. 2, when the second frame 20 is overlapped on the first frame 10 in a spaced-apart, non-contact state, the weld width W of the rib weld 42 is a second width W2, which is the minimum width at the contact surface 420. 3, when the second frame 20 is overlapped with the first frame 10 in a spaced-apart state without contacting the first frame 10, and the rib weld 42 is constricted between the first frame 10 and the second frame 20, the weld width W of the rib weld 42 is as follows: In this case, the weld width W of the rib weld 42 is the third width W3, which is the minimum width at the contact surface 420.

[0016] According to the above embodiment, as shown in Fig. 2, the welded structure 40 includes a rib weld 42 formed by welding the first frame 10 and the second frame 20 along the rib 14. With this configuration, the weld area of ​​the rib 14 can be increased, thereby reducing stress concentration on the rib 14. This prevents damage to the frame structure 100 due to cracks occurring in the rib weld 42, for example.

[0017] Furthermore, according to the above embodiment, the weld width W of the rib weld 42 is 80% or more of the thickness t1, t2 of the frame 10, 20 having the smaller thickness t1, t2, of the first frame 10 and the second frame 20. This configuration can improve the strength of the rib weld 42. This more reliably prevents damage to the frame structure 100.

[0018] Furthermore, according to the above embodiment, the rib welds 42 are formed by welding the first frame 10 and the second frame 20 together parallel to the ribs 14. That is, as shown in FIG. 3, the rib welds 42 are formed along a direction different from the stacking direction LD of the first frame 10 and the second frame 20. With this configuration, stress is applied in a direction different from the stacking direction LD of the first frame 10 and the second frame 20, making it difficult for the first frame 10 and the second frame 20 to peel off. This more reliably prevents damage to the frames 10, 20 due to cracks in the rib welds 42, for example.

[0019] B. Other Embodiments: (B1) The first frame 10 and the second frame 20 may each have different thicknesses t1 and t2 at various portions. For example, in the first frame 10, the main body 13 formed by the first opposing surface 11 and the rib connecting surface 12 and the rib 14 may have different thicknesses t1. In this case, the weld width W of the rib weld 42 is determined based on the thicknesses t1 and t2 of the frames 10 and 20 in the vicinity of the rib weld 42.

[0020] (B2) The shape of each frame 10, 20 may be a shape other than a rectangular tube. For example, the shape of each frame 10, 20 may be a half-split shape. In other words, the cross-sectional shape of each frame 10, 20 may be an open cross-sectional shape with one side open.

[0021] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features of the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0022] 10...first frame, 11...first opposing surface, 12...rib connection surface, 13...main body, 14...rib, 15...end of first frame, 20...second frame, 21...second opposing surface, 22...base surface, 25...end of second frame, 27...slit, 40...welded structure, 41...end welded portion, 42...rib welded portion, 100...frame structure, 121...first connecting surface, 122...second connecting surface, 420...contact surface, D1...inner diameter of first frame, D2...inner diameter of second frame, LD...stacking direction, R...area, SP...internal space, t1...thickness of first frame, t2...thickness of second frame, TD...thickness direction, W...welding width, W1...first width, W2...second width, W3...third width

Claims

[Claim 1] A welded structure of a frame, an end weld formed by welding a region spanning the first frame and the second frame at at least one end of a first frame having ribs connected to two opposing surfaces and a second frame superimposed on the first frame; a rib weld portion formed by welding the first frame and the second frame along the rib, A welded structure of a frame, wherein the weld width of the rib weld is 80% or more of the thickness of the thinner frame out of the first frame and the second frame.

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