Manufacturing method of square cylinder and manufacturing device of cylinder body

Abstract

Provided is a method for manufacturing a square tube, which suppresses deformation at both ends of the square tube in the tube axis direction, improves the shape accuracy of a quadrangle even in a cross-section in the direction orthogonal to the tube axis, and is not susceptible to material breakage. A method for manufacturing a square tube, which is for manufacturing a square tube having a first side surface section and a second side surface section that face each other, the method comprising the steps of: disposing a plate-like plate on the inside of a tube body to be molded; a step for forming a cylindrical intermediate body by inserting a cylindrical body including a plate inside into a groove of a support-side mold and deforming the cylindrical body to form a first side surface part; a plate-shaped plate and a movable plate capable of moving relative to the plate-shaped plate are arranged on the inner side of the middle body; and an intermediate body including the plate and the movable plate inside is inserted into the groove of the support-side mold to deform the intermediate body to form a second side surface portion, and in the step of forming the second side surface portion, the movable plate is pressed in the direction opposite to the direction in which the plate is inserted into the groove.

Description

Technical Field

[0001] This invention relates to a method for manufacturing a square tube and an apparatus for manufacturing the tube body. Background Technology

[0002] Patent document 1 discloses the following: For a cylindrical housing component, a square cylindrical shape that conforms to the shape of a battery cell is formed by using a mold and a molding component.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2006-059804 Summary of the Invention

[0004] Patent document 1 discloses a method based on Figure 7 A, Figure 7 The two forming methods are: the forming method of B and the forming method based on Figure 8A and Figure 8B.

[0005] In reference 1 Figure 7 A, Figure 7 In the example described in B, such as... Figure 7 As shown in Figure A, the molded component 35 is inserted into the inner side of the cylindrical shell component 25, therefore, as Figure 7 When it becomes a square as shown in B, it will be like... Figure 7 As shown in B, a gap is generated between the molding part 35 and the housing part 25 (outer housing 8) side portion (the portion forming the short side of the rectangular tube), making it difficult to form the shape of the side portion with high precision.

[0006] In the example described in Figures 8A and 8B of reference 1, since the forming is performed with tensile force applied in a direction orthogonal to the cylinder axis of the shell component 25, the end of the flat portion (the portion forming the long side of the rectangular cylinder) is as follows: Figure 9 The material deforms due to tensile force. Therefore, it needs to be removed by cutting to form a straight shape. In this example, the side portion is semi-circular and the cross-section is approximately elliptical. However, if the side portion is also made straight to form a rectangular tube, there is a tendency for residual radius (R) at the corners, resulting in an insufficiently shaped corner. If the tensile force is increased to fully shape the corners, the material may fracture.

[0007] Therefore, the purpose of this invention is to provide a method for manufacturing a square tube that suppresses deformation at both ends of the square tube along the tube axis, improves the shape accuracy of the quadrilateral in the cross section in the direction orthogonal to the tube axis, and makes the material less prone to breakage.

[0008] This invention discloses a method for manufacturing a square tube, which manufactures a square tube having a first side surface and a second side surface that are opposite to each other. The method for manufacturing the square tube includes the following steps: placing a plate-shaped plate on the inner side of a tube body that is to be formed; inserting the tube body containing the plate on the inner side into a groove of a support-side mold to deform the tube body to form the first side surface, thus creating a cylindrical intermediate body; placing a plate-shaped plate and a movable plate that can move relative to the plate-shaped plate on the inner side of the intermediate body; and inserting the intermediate body containing the plate and the movable plate on the inner side into a groove of a support-side mold to deform the intermediate body to form the second side surface. In the step of forming the second side surface, the movable plate is pressed in the opposite direction to the direction in which the plate is inserted into the groove.

[0009] The present invention discloses a manufacturing apparatus for a cylindrical body, comprising: a plate disposed on the inner side of the cylindrical body to be formed and a movable plate that is movable relative to the plate; and a support-side mold having a groove for inserting the cylindrical body into which the plate and the movable plate are disposed on the inner side.

[0010] In the above-described manufacturing method and apparatus, the opening on the insertion side of the groove in the support-side mold is wide, and an inclined surface that narrows towards the bottom of the groove may be provided.

[0011] Invention Effects

[0012] According to the present invention, since the square tube is formed by stamping, it is less prone to producing defects such as... Figure 9 The deformation shown reduces the need to cut off the curved portion to form a straight shape. Furthermore, by forming the first and second side portions using a plate and a mold, shape accuracy is improved. The risk of material breakage during forming is also reduced. Attached Figure Description

[0013] Figure 1 This is a diagram illustrating the manner in which the pre-forming cylindrical body 11 and the post-forming square cylindrical body 12 are formed.

[0014] Figure 2 This is a diagram illustrating the first side face forming plate 21.

[0015] Figure 3 This is a diagram illustrating the second side face forming device 22.

[0016] Figure 4 This is a diagram illustrating the support-side mold 40.

[0017] Figure 5 This diagram illustrates the insertion process of the first side face forming plate.

[0018] Figure 6 (a) and Figure 6 (b) is a diagram illustrating the first side face forming process.

[0019] Figure 7 This is a diagram illustrating the process of setting up the second side face forming device.

[0020] Figures 8(a) and 8(b) illustrate the second side face forming process.

[0021] Figure 9 This diagram illustrates the previous methods of deformation.

[0022] Figure 10 This diagram illustrates the possible ways in which a depression can be created in a flat area. Detailed Implementation

[0023] 1. The object to be shaped

[0024] like Figure 1 As shown, the object being molded (the object to be molded) is as follows before molding. Figure 1 The seamless cylindrical tubular component on the upper side of the paper (sometimes referred to as "pre-forming tubular body 11") becomes, after forming, as... Figure 1 The square tube on the underside of the paper (sometimes referred to as "square tube 12 after forming").

[0025] The preformed cylindrical body 11 is not limited to, for example Figure 1 The cylinder shown can also be other shapes. From the viewpoint of improving the uniformity of the wall thickness of the square cylinder 12 after forming, the cylinder 11 before forming is preferably a cylinder.

[0026] like Figure 1 As shown, the formed square tube 12 is a cylindrical body with a rectangular cross-section. However, the difference between the long side and the short side of this rectangle is large, making it flat. Here, the surface formed by the short side is called the side surface, one side of which is called the first side surface 13, and the other side of which is called the second side surface 14. Furthermore, the surface formed by the long side is called the planar surface, one side of which is called the first planar surface 15, and the other side of which is called the second planar surface 16.

[0027] The material, properties, size, etc. of the pre-forming cylinder 11, which is the object to be formed, are not particularly limited, but the manufacturing method of the present invention is particularly effective in materials with low rigidity (easily deformable).

[0028] Specifically, the effect is significant in aluminum and aluminum alloys, but it is not limited to these; examples include stainless steel, copper, iron, titanium, and nickel. From the perspective of material strength, examples include tensile strength of 70MPa to 300MPa, endurance of 30MPa to 200MPa, and elongation of 2% to 30%.

[0029] The effect is significant when the plate thickness is below 1.0mm, especially when it is below 0.3mm.

[0030] 2. Manufacturing method

[0031] The manufacturing apparatus used in the manufacturing method of the present invention is not particularly limited in manner, and examples can be given as follows. Figures 2-4 , Figure 7 The diagram shown is for illustrative purposes. The manufacturing apparatus involved in this example includes a first side forming plate 21 ( Figure 2 ), second side face forming device 22 ( Figure 3 ), cylinder block assembly 30 (reference) Figure 7 ) and support side mold 40 ( Figure 4 ).

[0032] 2.1. First side face forming plate

[0033] like Figure 2 As shown, the first side forming plate 21 is a cuboid-shaped plate component that forms part of the first side portion 13, part of the first planar portion 15, and part of the second planar portion 16 of the formed square cylinder 12. As described later, the first side forming plate 21 is inserted into the inner side of the pre-forming cylinder 11, thus also forming the inner surface of the formed square cylinder 12. Therefore, the thickness T of the first side forming plate 21 is approximately the same as the size between the inner surfaces of the opposing first planar portion 15 and second planar portion 16 of the formed square cylinder 12.

[0034] Furthermore, the width W of the first side forming plate 21 is configured to be able to be inserted into the inner side of the forming pre-cylinder 11. When the forming pre-cylinder 11 is a cylinder, the first side forming plate 21 is configured to be able to be inserted along the inner diameter of the forming pre-cylinder 11 (see reference). Figure 5 For example, it can be set such that, when the lower two edges 21a of the four edges 21a formed by the corners of the quadrilateral formed by the width (W) and the thickness (T) are in contact with the inner surface of the pre-forming cylinder 11, the gap between the upper two edges 21a and the inner surface of the pre-forming cylinder 11 is in the range of 0.05 mm to 1 mm.

[0035] The length L of the first side forming plate 21 is configured to be longer than the length of the cylindrical body 11 in the cylindrical axis direction before forming (reference). Figure 5 ).

[0036] Furthermore, from the viewpoint of preventing damage to the pre-forming cylindrical body 11, the edge 21a (corner) of the first side forming plate 21, especially the edge 21a that contacts the pre-forming cylindrical body 11, is preferably arc-shaped (so-called R-shape). The radius of the R-shape is not particularly limited, but is preferably 0.1 mm or more, but may also correspond to the R-shape of the final formed square cylinder.

[0037] 2.2. Second side face forming device

[0038] like Figure 3 As shown, the second side forming device 22 is a device comprising two cuboid-based plate-shaped components, which form the second side surface 14, the first flat surface 15, and the second flat surface 16 of the formed square cylinder 12. As described later, the second side forming device 22 also forms the inner surface of the formed square cylinder 12 by inserting each plate into the inner side of the pre-forming cylinder 11 (intermediate body 11). Figure 3 As can be seen, the second side face forming device 22 is composed of multiple components. Specifically, in this embodiment, the second side face forming device 22 includes a second side face forming plate 23, a movable plate 24, and a plate pressing rod / guide 25. The components and their relationships will be explained below.

[0039] [Second Side Face Forming Plate]

[0040] The second side forming plate 23 is a cuboid-shaped plate component that forms part of the second side 14, part of the first planar portion 15, and part of the second planar portion 16 of the formed square cylinder 12. As described later, the second side forming plate 23 is inserted into the inside of the intermediate body 11 formed in the first side forming process (refer to FIG. 8), thus also forming the inner surface of the formed square cylinder 12. Therefore, the thickness T of the second side forming plate 23 is approximately the same as the size between the inner surfaces of the opposing first planar portion 15 and second planar portion 16 of the formed square cylinder 12.

[0041] Furthermore, the second side forming plate 23 is configured to be able to be inserted into the inner side of the intermediate body 11 together with the movable plate 24, with a width (the size in the vertical direction on paper) (refer to FIG8). The length L of the second side forming plate 23 is configured to be longer than the length of the intermediate body 11 in the cylindrical axis direction.

[0042] Furthermore, from the viewpoint of preventing damage to the intermediate body 11, the edge (corner) of the second side forming plate 23, especially the edge that contacts the intermediate body 11, is preferably arc-shaped (so-called R-shape). The radius of the R-shape is not particularly limited, but is preferably 0.1 mm or more, but may also correspond to the R-shape of the finally obtained formed square cylinder.

[0043] [Movable board]

[0044] The movable plate 24 is a plate-shaped component based on a cuboid, which, as described later, is a plate-shaped component that applies tensile force to the intermediate body 11 when the second side portion 14 is formed in the manufacturing method of the square tube.

[0045] As will be described later, the movable plate 24 is also inserted into the inside of the intermediate body 11 formed in the first side forming process (refer to FIG8), so the thickness T of the movable plate 24 is approximately the same as the size between the inner surfaces of the opposing first flat portion 15 and the second flat portion 16 of the formed square tube 12.

[0046] Furthermore, as described above, the movable plate 24 is configured to be able to be inserted into the inner side of the intermediate body 11 together with the second side forming plate 23, with a width (the size in the vertical direction on paper) (refer to FIG8). The length of the movable plate 24 is configured to be longer than the length of the intermediate body 11 in the cylindrical axis direction and the second side forming plate 23.

[0047] Furthermore, from the viewpoint of preventing damage to the intermediate body 11, the edges (corners) of the movable plate 24, especially the edges that contact the intermediate body 11, are preferably arc-shaped (so-called R-shape). The radius of the R-shape is not particularly limited, but is preferably 0.1 mm or more, although it may correspond to the R-shape of the final formed square cylinder.

[0048] [Plate pressing rod also serves as a guide]

[0049] like Figure 3 As shown, the plate pressing bar / guide 25 consists of the second side forming plate 23 and the movable plate 24 arranged in their width direction (vertical direction on the paper) and maintaining the movable plate 24 as... Figure 3 The component that moves in the width direction is indicated by the middle arrow P. In this configuration, the plate pressing bar / guide 25 is respectively disposed on both ends of the second side forming plate 23 and the movable plate 24 in the length direction.

[0050] In this configuration, each plate pressing rod / guide 25 consists of two rods 26. These two rods 26 are arranged to extend across the width direction of the second side face forming plate 23 and the movable plate 24, clamping them from both sides in the thickness direction of the second side face forming plate 23 and the movable plate 24. In this configuration, the rods 26 are fixed to the second side face forming plate 23 by bolts 25a, and as shown by arrow Q, the second side face 14 can be formed by pressing downwards. On the other hand, the rods 26 are not fixed to the movable plate 24. Thus, as described above, the movable plate 24 can move in its width direction between the two rods 26, and the second side face forming plate 23 and the movable plate 24 can move relative to each other.

[0051] 2.3. Cylinder block assembly 30

[0052] like Figure 7 As shown, the cylinder device 30 is a device that can extend and retract the cylinder 31 hydraulically. This cylinder device 30 is not particularly limited, and known cylinder devices can be used.

[0053] 2.4. Support side mold

[0054] like Figure 4 As shown, the support-side mold 40 is a component with a groove 41, which forms the outer shape of the formed square cylinder 12. Therefore, the width WM of the groove 41 is approximately the same as the size between the outer surfaces of the first planar portion 15 and the second planar portion 16 of the formed square cylinder 12.

[0055] In groove 41, the depth D of the groove, excluding the guide portion 41a, is formed to be at least larger than the size between the two side portions of the formed square cylinder 12. Furthermore, the bottom 41b of groove 41 is formed flat to allow the formation of the first side portion 13 and the second side portion 14 of the formed square cylinder 12. Additionally, the sidewall surface from the opening (insertion port) of the groove to the bottom of groove 41 is flat to allow the formation of the first flat portion 15 and the second flat portion 16 of the formed square cylinder 12. This sidewall surface shapes the surface characteristics of the formed square cylinder 12, and for smooth forming, the surface roughness of the sidewall surface of groove 41 is preferably small, and coating is also possible.

[0056] The length (LM) of the groove 41 is configured to be longer than the length of the preformed cylinder 11.

[0057] Furthermore, in this embodiment, the support-side mold 40 has a Y-shaped guide portion 41a, which has a tapered surface from the opening end (insertion port) in the depth direction (D direction) of the groove 41 towards the bottom of the groove. This makes the insertion of the preformed cylinder 11 into the groove 41 smoother. The unfolding angle of the Y is not particularly limited and can be set to 30 degrees to 120 degrees.

[0058] 3. Manufacturing method of square tube

[0059] Next, an example of a method for manufacturing a square tube will be described. This method includes a first side forming plate insertion process, a first side forming process, a second side forming device installation process, and a second side forming process. Each process will be described below.

[0060] 3.1. Insertion process of the first side face forming plate

[0061] In the insertion process of the first side forming plate, such as Figure 5 As shown, the first side forming plate 21 is inserted into the inner side of the pre-forming cylindrical body 11, which is a seamless tube in the shape of a cylinder. As described above, this insertion is configured such that the width direction of the first side forming plate 21 is the diameter direction of the pre-forming cylindrical body 11.

[0062] 3.2. First side face forming process

[0063] In the first side face forming process, the forming front cylinder 11, on which the first side face forming plate 21 is disposed, is inserted into the groove 41 of the support side mold 40 to form the first side face 13. Specifically, as Figure 6 (a) Figure 6 As shown in (b), the first side forming plate 21, which is disposed on the inner side of the forming cylinder 11, is inserted into the groove 41 in such a way that the width direction of the plate 21 is the depth direction of the groove 41 of the support mold 40.

[0064] Thus, the preformed cylinder 11 is deformed by being sandwiched between the side wall of the groove 41 and the first side forming plate 21, forming the first flat portion 15 and the second flat portion 16 in sequence.

[0065] As an intermediate process Figure 6 In state (a), through deformation, a gap 11a is formed on the insertion side (guide portion 41a side) of the groove 41 at the insertion side of the groove 41 in the portion of the cylindrical body 11 that cannot be tightly fitted with the first side forming plate 21 before forming. This gap 11a is slightly larger than the width of the groove 41, so if the first side forming plate 21 is further moved along the depth direction of the groove 41 ( Figure 6 (a) Pressing in the direction of arrow A will produce a force opposite to the pressing force. Figure 6 (a) Arrow B).

[0066] In addition, in the pre-forming cylinder 11, a small gap 11b is also generated on the bottom 41b side of the groove 41, which prevents the pre-forming cylinder 11 from sealing tightly with the first side forming plate 21.

[0067] If from Figure 6 (a) In the state of resisting the force of arrow B, the first side face forming plate 21 is inserted into the groove 41 in the direction of arrow A, then as follows: Figure 6 As shown in (b), the first side surface 13 is formed by the partial deformation of the gap 11b, which is sandwiched between the bottom 41b of the groove 41 and the first side surface forming plate 21. At this time, during the deformation (crushing) of the gap 11b, sometimes a portion of the excess material... Figure 6 (b) Moves to the first plane portion 15 or the second plane portion 16 as indicated by arrow C. Therefore, the first plane portion 15 or the second plane portion 16 may become as follows: Figure 10 The necked shape (bent shape) is shown. However, according to this method, due to the force generated by arrow B above due to the presence of gap 11a, the material is stretched and extended, which can absorb the movement of material accompanying the crushing of gap 11b, and can suppress the movement of material in this process stage. Figure 10 The necking shape shown is generated.

[0068] Then, the first side forming plate 21 and the pre-forming cylinder 11 are removed from the slot 41, and the first side forming plate 21 is further removed from the pre-forming cylinder 11. The pre-forming cylinder 11 at this time is referred to as the intermediate body 11.

[0069] 3.3. Second Side Face Forming Device Installation Process

[0070] In the process of setting up the second side forming device, such as Figure 7 As shown in Figure 8, a second side face forming plate 23 and a movable plate 24 are inserted into the inner side of the intermediate body 11, and are mounted on the plate pressing rod / guide 25, and a cylinder device 30 is provided. Specifically, as shown in Figure 8, the second side face forming plate 23 and the movable plate 24 are arranged inside the intermediate body 11. At this time, on the side with the aforementioned gap 11a (refer to...) Figure 6 A second side forming plate 23 is configured, and a movable plate 24 is configured on the side of the first side 13 formed in the previous process. Then, in this process, the second side forming plate 23 is inserted into the groove 41 in the direction of the bottom 41b side of the groove 41 that becomes the support mold 40.

[0071] And, as Figure 7 As shown, a second side forming plate 23 and a movable plate 24 extend from the outer sides of both ends of the support-side mold 40 along its length. The second side forming plate 23 is fixed to the rod 26 of the plate pressing rod / guide 25, and the movable plate 24 is held to the rod 26 of the plate pressing rod / guide 25 so that it can move vertically on the paper surface. Moreover, the movable plate 24 extends protruding from the rod 26 and is held from below by the cylinder device 30. The vertical movement of the movable plate 24 on the paper surface is controlled by the vertical movement of the cylinder 31 of the cylinder device 30.

[0072] 3.4. Second side face forming process

[0073] In the second side forming process, as described in the second side forming device setting process, each part is arranged in the groove 41 of the support side mold 40, and the intermediate body 11, in which the second side forming plate 23 and the movable plate 24 are arranged, is inserted into the groove 41.

[0074] As a result, the intermediate body 11 is deformed between the side wall of the groove 41 and the second side face forming plate 23, forming the first flat portion 15 and the second flat portion 16.

[0075] In the state shown in Figure 8(a), which is an intermediate process, a small gap 11c is generated in the intermediate body 11 at the bottom 41b side of the groove 41, preventing the intermediate body 11 from sealing tightly with the second side face forming plate 23. Furthermore, in this process, as shown in Figure 8(a), a small gap 11c is generated in the intermediate body 11 at the bottom 41b side of the groove 41, preventing the intermediate body 11 from sealing tightly with the second side face forming plate 23. Figure 6(a) The insertion side of the groove 41 shown does not produce a gap like the gap 11a, therefore no force is generated on the tensile material as indicated by arrow B due to the gap (see reference). Figure 6 ).

[0076] If the first side face forming plate 21 is inserted into the groove 41 in the direction of arrow D in Figure 8(a) from the state shown in Figure 8(a), then as shown in Figure 8(b), the second side face 14 is formed by the deformation of the gap 11c, which is sandwiched between the bottom 41b of the groove 41 and the second side face forming plate 23. At this time, when the gap 11c deforms (crushes), sometimes a portion of the excess material moves to the first planar portion 15 or the second planar portion 16 as shown by arrow F in Figure 8(b). Thus, the first planar portion 15 or the second planar portion 16 may become as shown in Figure 8(b). Figure 10 The necked shape (bent shape) is shown. However, in this method, as... Figure 7 As shown by arrow Q, the rod 26 is pressed downwards, and the second side forming plate 23 is pressed downwards simultaneously, while the cylinder device 30 is used... Figure 7 As indicated by arrow R, the movable plate 24 is pressed upwards, thereby applying force to the intermediate body 11 as shown by arrow E in Figure 8(a), and pressing the intermediate body 11 towards the groove 41 in the direction of arrow D. Through the force of arrow E on the movable plate 24, the material is stretched and extended, absorbing material movement from the gap 11c, and suppressing movement within the final formed square cylinder 12. Figure 10 The necking phenomenon is shown.

[0077] In addition, the size of the square tube 12 in the width direction can also be adjusted by using the tensile force generated by the movable plate 24.

[0078] Then, the second side forming plate 23, the movable plate 24 and the formed square tube 12 are removed from the groove 41, and the second side forming plate 23 and the movable plate 24 are further removed from the formed square tube 12.

[0079] 4. Effects, etc.

[0080] According to the present invention, since the forming of the square tube is a stamping process, it is less prone to producing defects such as... Figure 9 The deformation shown does not require cutting to form a straight shape. Furthermore, by forming the first and second side portions using a plate and a mold, shape accuracy is improved. The risk of material breakage during forming is also reduced.

[0081] Furthermore, by applying tensile force to the material during the formation of the first and second side portions, it is possible to suppress [the following]. Figure 10 The necking phenomenon is shown.

[0082] Symbol Explanation

[0083] 11-Pre-forming cylindrical body, 12-Formed square cylinder (square tube), 21-First side forming plate, 23-Second side forming plate, 24-Modible plate, 25-Plate pressing rod and guide, 30-Cylinder body device, 40-Supporting side mold.

Claims

1. A method for manufacturing a square tube, comprising the following steps: A plate-shaped plate is arranged on the inside of the cylinder that is being shaped; The cylinder containing the plate on its inner side is inserted into the groove of the support mold to deform the cylinder and form the first side face, thus creating a cylindrical intermediate body. A plate-shaped plate and a movable plate that can move relative to the plate-shaped plate are disposed on the inner side of the intermediate body; and The intermediate body, which includes the inner plate and the movable plate, is inserted into the groove of the support-side mold, thereby deforming the intermediate body to form the second side face. In the process of forming the second side face, the movable plate is pressed in the opposite direction to the direction in which the plate is inserted into the groove.

2. The method for manufacturing a square tube according to claim 1, characterized in that, In the support-side mold, the opening on the insertion side of the groove is wide and has an inclined surface that narrows towards the bottom of the groove.

3. A cylindrical body manufacturing apparatus, characterized in that, have: A plate disposed on the inner side of the cylinder to be formed, and a movable plate that can move relative to the plate; and The support-side mold has a groove for inserting the cylinder into which the plate and the movable plate are disposed on the inner side.

4. The apparatus for manufacturing a cylindrical body according to claim 3, characterized in that, In the support-side mold, the opening on the insertion side of the groove is wide and has an inclined surface that narrows towards the bottom of the groove.

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