Cylinders and equipment

Abstract

To provide a technology which is advantageous for improving strength of a cylindrical body.SOLUTION: A cylindrical body includes: a cylindrical member 3 made by forming a metal plate 1 into a cylindrical shape such that an end surface 10 and an end surface 20 of the metal plate 1, having the end surface 10 and the end surface 20, face each other; and a nonmetallic adhesive member 9 which bonds the end surface 10 and the end surface 20 to each other. The adhesive member 9 is provided between an adhesion portion 11 of the end surface 10 and an adhesion portion 22 of the end surface 20. The adhesion portion 11 and the adhesion portion 22 are not parallel to each other. A contact portion 13 of the end surface 10 and a contact portion 24 of the end surface 20 contact with each other.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cylindrical body. [Background technology]

[0002] By forming a metal plate into a cylindrical shape, the cylindrical body can be manufactured inexpensively. Patent Document 1 discloses a manufacturing method for a transport roller in which a pair of end faces of a metal plate are opposed to each other to form a cylindrical shape. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-121682 A Summary of the Invention [Problem to be solved by the invention]

[0004] A cylindrical body such as that in Patent Document 1 has a problem of insufficient strength. Therefore, an object of the present invention is to provide a technique that is advantageous in increasing the strength of a cylindrical body. [Means for solving the problem]

[0005] The first cylinder of the means for solving the above problem comprises a cylindrical member formed by molding a metal plate having a first end face and a second end face into a cylindrical shape so that the first end face and the second end face of the metal plate face each other, and a non-metallic adhesive member that bonds the first end face and the second end face, wherein the adhesive member is provided between a first portion of the first end face and a second portion of the second end face, and the first portion and the second portion are non-parallel to each other.

[0006] The second cylinder of the means for solving the above problem comprises a cylindrical member formed by molding a metal plate having a first end face and a second end face into a cylindrical shape so that the first end face and the second end face of the metal plate face each other, and a non-metallic adhesive member that bonds the first end face and the second end face, wherein the adhesive member is provided between a first portion of the first end face and a second portion of the second end face, and a third portion of the first end face and a fourth portion of the second end face are in contact. Effect of the Invention

[0007] According to the present invention, it is possible to provide a technique that is advantageous in increasing the strength of a cylindrical body. [Brief description of the drawings]

[0008] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] Schematic diagram illustrating a manufacturing method of a cylindrical body. [Figure 6] Schematic diagram illustrating a manufacturing method of a cylindrical body. [Figure 7] Schematic diagram illustrating a manufacturing method of a cylindrical body. [Figure 8] Schematic diagram illustrating a manufacturing method of a cylindrical body. [Figure 9] Schematic diagram illustrating a manufacturing method of a cylindrical body. [Figure 10] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description and drawings, common reference numerals are used to designate components common to multiple drawings. Therefore, common components will be described with mutual reference to multiple drawings, and descriptions of components with common reference numerals will be omitted as appropriate.

[0010] A cylindrical body 2 according to this embodiment will be described with reference to FIG. 1(a). The cylindrical body 2 includes a cylindrical member 3 formed by forming a metal plate 1 into a cylindrical shape so that the end faces 10 and 20 of the metal plate 1 face each other. The cylindrical member 3 has a joint 5, an inner peripheral surface 6, an outer peripheral surface 7, an end face 4, and an end face 8. At the joint 5, the end faces 10 and 20 face each other. The cylindrical member 3 is located between the end faces 4 and 8. In an orthogonal coordinate system (x, y, z), the direction (axial direction) along the central axis of the cylindrical member 3 is the z direction, and the directions perpendicular to the z direction are the x direction and the y direction. Hereinafter, the z direction is referred to as the axial direction z. The end faces 4 and 8 are aligned in the axial direction z of the cylindrical member 3. Herein, lining up two objects in a certain direction means that the straight line connecting the two objects is aligned in a certain direction. Two objects aligned in a certain direction may be adjacent or spaced apart. End surface 4 and end surface 8 aligned in the axial direction z are spaced apart.

[0011] In the joint 5, an end surface 10 and an end surface 20 extend from the inner peripheral surface 6 to the outer peripheral surface 7. The joint 5 is produced by bending the metal sheet 1 into a cylindrical shape and abutting or bonding the end surfaces 10, 20 to each other. It is preferable that the joint 5 has no gaps.

[0012] Simply put, forming the metal sheet 1 into a cylindrical shape means rolling the metal sheet 1. The end surface 20 of the metal sheet 1 is aligned with the end surface 10. At least a part of the end surface 10 of the metal sheet 1 and at least a part of the end surface 20 of the metal sheet 1 form the joint 5 of the cylindrical member 3. If the cylindrical member formed by rolling the metal sheet 1 is not cut, the entire end surface 10 of the metal sheet 1 can become the joint 5 of the cylindrical member 3, and the entire end surface 20 of the metal sheet 1 can become the joint 5 of the cylindrical member 3. If the cylindrical member formed by rolling the metal sheet 1 is cut, a part of the end surface 10 of the metal sheet 1 can become the joint 5 of the cylindrical member 3, and a part of the end surface 20 of the metal sheet 1 can become the joint 5 of the cylindrical member 3.

[0013] In addition to the end faces 10 and 20, the metal plate 1 has a back surface 16, a front surface 17 along the back surface 16, and an end surface 14 and an end surface 18 along the end surface 14. At least a part of the back surface 16 of the metal plate 1 becomes the inner peripheral surface 6 of the cylindrical member 3, and at least a part of the front surface 17 of the metal plate 1 becomes the outer peripheral surface 7 of the cylindrical member 3. If the cylindrical member made by rolling the metal plate 1 is not cut, the entire back surface 16 of the metal plate 1 can become the inner peripheral surface 6 of the cylindrical member 3, and the entire front surface 17 of the metal plate 1 can become the outer peripheral surface 7 of the cylindrical member 3. If the cylindrical member made by rolling the metal plate 1 is not cut, the end surface 14 of the metal plate 1 becomes the end surface 4 of the cylindrical member 3, and the end surface 18 of the metal plate 1 becomes the end surface 8 of the cylindrical member 3. If the cylindrical member made by rolling the metal plate 1 is cut, a part of the back surface 16 of the metal plate 1 can become the inner peripheral surface 6 of the cylindrical member 3, and a part of the front surface 17 of the metal plate 1 can become the outer peripheral surface 7 of the cylindrical member 3. Furthermore, when the cylindrical member obtained by rolling the metal plate 1 is cut, at least one of the end faces 4 and 8 of the cylindrical member 3 will not coincide with the end faces 14 and 18 of the metal plate 1.

[0014] The cylindrical member 3 has a metal-containing portion that contains, for example, a metal. The metal contained in the metal-containing portion of the cylindrical member 3 is, for example, any one of iron, copper, magnesium, and aluminum. The metal-containing portion of the cylindrical member 3 may be an alloy, and may be, for example, an iron alloy, a copper alloy, a magnesium alloy, or an aluminum alloy.

[0015] FIG. 1(a) shows the length L of the cylindrical member 3 in the z direction (axial direction z). The length L is the distance between the end face 4 and the end face 8.

[0016] FIG. 1(b) shows a cross-sectional view of the cylindrical body 2 in a plane perpendicular to the z direction (axial direction z). FIG. 1(c) shows an enlarged view of the vicinity of the joint portion 5. In the cylindrical coordinate system (r, q, z), the radial direction r, the circumferential direction q, and the axial direction z of the cylindrical member 3 are defined. The thickness T of the cylindrical member 3 is half of the difference between the outer diameter (external diameter) Ra and the inner diameter (internal diameter) Rb of the cylindrical member 3 (T = (Ra - Rb) / 2).

[0017] This embodiment is suitable when the length L of the cylindrical member 3 in the axial direction z (the distance between the end face 4 and the end face 8) is larger than the outer diameter (external diameter Ra) of the cylindrical member 3 (L > Ra). According to this embodiment, it is advantageous for enhancing the torsional rigidity around the central axis in the elongated cylindrical member 3 that satisfies L > Ra. However, it is also applicable when the length L of the cylindrical member 3 in the axial direction z is the same as the outer diameter (external diameter Ra) of the cylindrical member 3 (L = Ra) or smaller than the outer diameter (external diameter Ra) of the cylindrical member 3 (L < Ra).

[0018] The cylindrical body 2 includes a non-metallic adhesive member 9 that adheres the end face 10 and the end face 20. As the non-metallic adhesive member 9, resin adhesives such as acrylic adhesives, epoxy adhesives, urethane adhesives, and silicone adhesives, and inorganic adhesives (ceramic adhesives) such as alumina adhesives, silica adhesives, and zirconia adhesives can be used.

[0019] The adhesive member 9 may be in contact with the metal-containing portion of the cylindrical member 3. The metal contained in the metal-containing portion of the cylindrical member 3 with which the adhesive member 9 is in contact may be any one of iron, copper, magnesium, or aluminum, as described above. Alternatively, the adhesive member 9 may be in contact with a metal compound film covering the metal-containing portion. The metal element constituting the metal compound film with which the adhesive member 9 is in contact may be the same as the metal contained in the metal-containing portion. That is, the metal compound film with which the adhesive member 9 may be in contact may be a compound film of the metal contained in the metal-containing portion of the cylindrical member 3, and may be, for example, an iron compound film, a copper compound film, a magnesium compound film, or an aluminum compound film. The metal compound film with which the adhesive member 9 may be in contact may be an oxide film, a nitride film, or a carbide film. The metal compound film with which the adhesive member 9 may be in contact is typically a metal oxide film (natural oxide film) formed by natural oxidation of the metal contained in the metal-containing portion. In order to improve the wear resistance and corrosion resistance of the cylindrical body 2, a metal compound film can be formed by carrying out an oxidation treatment (for example, anodization), a nitriding treatment, a carbonization treatment, or the like.

[0020] The adhesive member 9 may include an intermediate portion 91 located between the end surface 10 and the end surface 20 and a non-intermediate portion 92 not located between the end surface 10 and the end surface 20, but the adhesive member 9 may not include the intermediate portion 92. That is, the adhesive member 9 may be present only between the end surface 10 and the end surface 20. For example, after forming the adhesive member 9 having the intermediate portion 91 and the non-intermediate portion 92, the non-intermediate portion 92 can be removed. The non-intermediate portion 92 is adhered to the whole or a part of at least one of the inner peripheral surface 6 and the outer peripheral surface 7. Typically, the non-intermediate portion 92 is adhered to a part of either the inner peripheral surface 6 or the outer peripheral surface 7.

[0021] The intermediate portion 91 of the adhesive member 9 is provided between the adhesive portion 11 of the end face 10 and the adhesive portion 22 of the end face 20. The adhesive portion 11 and the adhesive portion 22 may be non-parallel. By making the adhesive portion 11 and the adhesive portion 22 non-parallel in the joint 5, the bonding strength of the joint 5 is increased.

[0022] The non-parallel adhesive portion 11 and adhesive portion 22 face each other to form a tapered groove having a side wall formed by the adhesive portion 11 and adhesive portion 22. An intermediate portion 91 of the adhesive member 9 is provided in this tapered groove.

[0023] The adhesive member 9 can be formed in two or more places in the axial direction z of the cylindrical member 3. The application range of the adhesive that will become the adhesive member 9 is preferably within the tapered groove and a part of the inner circumferential surface 6 that continues from the tapered groove, and is preferably within a range of an opening angle of ±90° from the joint 5. Applying the adhesive within a range of an opening angle of ±90° can obtain sufficient torsional strength, but applying the adhesive beyond this range increases the amount of adhesive used, which tends to increase costs.

[0024] Contact portion 13 of end face 10 and contact portion 24 of end face 20 are in contact with each other. Contact portion 13 is the portion of end face 10 that is in contact with end face 20, and contact portion 24 is the portion of end face 20 that is in contact with end face 10. By providing contact region 58 in joint 5 where contact portion 13 and contact portion 24 are in contact with each other, the bonding strength of joint 5 is increased.

[0025] Providing the adhesive member 9 and providing the contact region 58 are each advantageous in terms of increasing the bonding strength. Furthermore, by combining the adhesive member 9 and the contact region 58, the change in the distance between the adhesive portion 11 and the adhesive portion 22 is suppressed by the contact region 58. Therefore, deterioration of the adhesive member 9 itself and a decrease in the adhesive force at the adhesive interface caused by a change in the distance between the adhesive portion 11 and the adhesive portion 22 are suppressed, thereby obtaining a synergistic effect of increasing the bonding strength of the joint 5.

[0026] FIG. 2 shows several examples of the form of the joint 5. FIG. 2(a) shows a first example, FIG. 2(b) shows a second example, FIG. 2(c) shows a third example, FIG. 2(d) shows a fourth example, FIG. 2(e) shows a fifth example, FIG. 2(f) shows a sixth example, FIG. 2(g) shows a seventh example, FIG. 2(h) shows an eighth example, FIG. 2(i) shows a ninth example, and FIG. 2(j) shows a tenth example.

[0027] In the first to sixth examples, the bonding portion 11 and the bonding portion 22 are non-parallel, and in the seventh to ninth examples, the bonding portion 11 and the bonding portion 22 are parallel. In the first, third, and fifth examples, the distance between the bonding portion 11 and the bonding portion 22 in the circumferential direction q becomes smaller as it is closer to the outer peripheral surface 7 than the inner peripheral surface 6. In the second, fourth, and sixth examples, the distance between the bonding portion 11 and the bonding portion 22 in the circumferential direction q becomes larger as it is closer to the outer peripheral surface 7 than the inner peripheral surface 6.

[0028] Figures 2(c), (d) and Figure 2(i) show the distance V between the boundary between the end face 10 and the inner peripheral surface 6 of the cylindrical member 3 and the boundary between the end face 20 and the inner peripheral surface 6 of the cylindrical member 3. Also shown is the distance U between the boundary between the end face 10 and the outer peripheral surface 7 of the cylindrical member 3 and the boundary between the end face 20 and the outer peripheral surface 7 of the cylindrical member 3. In the third and fifth examples, the distance V is greater than the distance U (V>U), and in the fourth and sixth examples, the distance V is smaller than the distance U (V<U). In the ninth example, the distance V and the distance U are equal (V=U) and both the distance V and the distance U are greater than zero (V=U>0). In consideration of the visibility of the drawings, the explanations of the distance V and the distance U are omitted in Figures 2(a), (b), (e), (f), (g), (h), (i), but the distance V and the distance U can be defined in the same way also in the first, second, seventh, eighth, and tenth examples. In the first and seventh examples, the distance V is greater than the distance U (V>U) and the distance U is zero (U=0). In the second and eighth examples, the distance V is smaller than the distance U (V<U) and the distance V is zero (V=0). In the tenth example, the distance V and the distance U are equal (V=U) and both the distance V and the distance U are zero (V=U=0).

[0029] In the first, second, seventh, and eighth examples, the contact portion 13 and the contact portion 24 are in contact with each other at the joint 5. In the first and seventh examples, a contact region 58 between the contact portion 13 and the contact portion 24 is located between the adhesive member 9 (middle portion 91) and the outer circumferential surface 7. In the second and eighth examples, a contact region 58 between the contact portion 13 and the contact portion 24 is located between the adhesive member 9 (middle portion 91) and the inner circumferential surface 6. In the tenth example, in the radial direction r, neither the adhesive member 9 nor a gap 59 is provided between the end face 10 and the end face 20, and a contact region 58 in which the end face 10 and the end face 20 are in contact with each other is provided from the inner circumferential surface 6 to the outer circumferential surface 7.

[0030] In the first, third, fifth and seventh examples, the non-intermediate portion 92 of the adhesive member 9 is adhered to the inner circumferential surface 6, and in the second, fourth, sixth and eighth examples, the non-intermediate portion 92 of the adhesive member 9 is adhered to the outer circumferential surface 7.

[0031] In the third, fourth, fifth and sixth examples, the end surface 10 and the end surface 20 are not in contact with each other, and the joint 5 does not include the contact portions 13 and 24. In the third and fourth examples, the entire end surface 10 may be the adhesive portion 11, and the entire end surface 20 may be the adhesive portion 22.

[0032] In the fifth and sixth examples, a gap 59 is provided between the end face 10 and the end face 20. The gap 59 is provided between the non-bonded portion 12 of the end face 10 and the non-bonded portion 23 of the end face 20. The non-bonded portion 12 does not contact the end face 20, is not bonded to the adhesive member 9, and may be exposed to the gap 59. The non-bonded portion 23 does not contact the end face 10, is not bonded to the adhesive member 9, and may be exposed to the gap 59. In the fifth example, the gap 59 is located between the adhesive member 9 (middle portion 91) and the outer circumferential surface 7. In the sixth example, the gap 59 is located between the adhesive member 9 (middle portion 91) and the inner circumferential surface 6.

[0033] In the first, second, seventh, and eighth examples, the adhesive member 9 and the contact region 58 are aligned in the radial direction r of the cylindrical member 3. In the fifth and sixth examples, the adhesive member 9 and the gap 59 are aligned in the radial direction r of the cylindrical member 3. In addition, the adhesive member 9, the gap 59, and the contact region 58 may be aligned in the radial direction r of the cylindrical member 3. For example, the gap 59 may be provided between the adhesive member 9 and the contact region 58 in the radial direction r. Alternatively, the adhesive member 9 may be provided between the gap 59 and the contact region 58 in the radial direction r, or the contact region 58 may be provided between the gap 59 and the adhesive member 9.

[0034] In another embodiment, the adhesive member 9 and the contact region 58 where the end face 10 and the end face 20 are in contact with each other may be arranged side by side in the axial direction z of the cylindrical member 3. Also, the adhesive member 9 and the void 59 may be arranged side by side in the axial direction z of the cylindrical member 3. For example, the joint 5 including the adhesive member 9 of the third, fourth, or ninth example and the joint 5 including the contact region 58 of the tenth example may be arranged side by side in the axial direction z of the cylindrical member 3. Also, the adhesive member 9, the void 59, and the contact region 58 may be arranged side by side in the axial direction z of the cylindrical member 3. For example, the void 59 may be provided between the adhesive member 9 and the contact region 58 in the axial direction z. Alternatively, the adhesive member 9 may be provided between the void 59 and the contact region 58 in the axial direction z, or the contact region 58 may be provided between the void 59 and the adhesive member 9.

[0035] When the joint portion 5 is composed only of the form of the 11th example and the adhesive member 9 is not used, the torsional rigidity becomes low. When the joint portion 5 is composed only of the form of the 10th example and the adhesive portions 11 and 21 are parallel at the Yoda of the joint portion 5, the adhesive area with the adhesive member 9 becomes small and the torsional rigidity is insufficient. Also, when the area of the contact region 58 is extremely small, the torsional rigidity becomes low. When the metal plate 1 is bent and formed into a cylindrical member, the circumference on the outer peripheral surface 7 side is insufficient, and a gap may occur on the outer peripheral surface 7 side at the joint portion 5. When an adhesive is applied to the gap on the outer peripheral surface 7 side, the adhesive may overflow from the gap, causing a step on the outer peripheral surface 7 and affecting the accuracy of the outer diameter and roundness. Also, when finish grinding the outer peripheral surface to increase the accuracy of the outer diameter and roundness, the adhesive applied to the gap on the outer peripheral surface may be removed by the grinding process, and it may not be possible to obtain the required torsional strength. Therefore, among the examples shown in FIG. 2, the first example (FIG. 2(a)) is suitable for parts that require high accuracy.

[0036] Using FIG. 3(a), the dimensions of each part in the vicinity of the joint portion 5 will be described. FIG. 3(a) shows the length C of the contact region 58 between the contact portion 13 and the contact portion 24 in the radial direction r. Also, FIG. 3(a) shows the length D of the adhesive member 9 in the radial direction r between the end faces 10 and 20. The adhesive member 9 between the end faces 10 and 20 means the middle portion 91 of the adhesive member 9, and the length D is the length of the middle portion 91 in the radial direction r. The sum of the length C and the length D is equal to the thickness T (C + D = T) or smaller than the thickness T (C + D < T). When a gap 59 (see FIGS. 2(e) and (f)) is provided in the joint portion 5, the sum of the length C and the length D becomes smaller than the thickness T (C + D < T). Using the length E of the gap 59 in the radial direction r, the sum of the length C, the length D, and the length E can be equal to the thickness T (C + D + E = T).

[0037] Contact region 58 between contact portion 13 and contact portion 24 can suppress misalignment between end face 10 and end face 20, so it is preferable that the area of ​​contact region 58 between contact portion 13 and contact portion 24 be as large as possible. Intermediate portion 91 can suppress misalignment between end face 10 and end face 20, so it is preferable that the volume of intermediate portion 91 be as large as possible. By making adhesive portion 11 and adhesive portion 22 non-parallel, it is possible to increase the volume of intermediate portion 91.

[0038] The length C of the contact region 58 is preferably 10% or more of the thickness T (C≧0.1×T), preferably 90% or less of the thickness T (C≦0.9×T), and also preferably 50% or more of the thickness T (C≧0.5×T). If the length C of the contact region 58 is extremely large (for example, C>0.9×T), the length D becomes extremely small, and the adhesive effect of the intermediate portion 91 becomes small. If the length C of the contact region 58 is extremely small (for example, C<0.1×T), the tapered groove becomes deep, and it becomes highly likely that the adhesive that becomes the adhesive member 9 will not be supplied to the vicinity of the contact region. If this happens, a gap 59 will be formed between the adhesive member 9 and the contact region 58. The presence of the gap 59 may not be advantageous in terms of improving strength. In consideration of these points, it can be said that it is preferable to satisfy C≧0.5×T. The length D of the intermediate portion 91 is preferably 10% or more of the thickness T (D≧0.1×T), and is preferably 90% or less of the thickness T (D≦0.9×T), and is also preferably 50% or less of the thickness T (D≦0.5×T). If the length D of the intermediate portion 91 is extremely small (for example, D<0.1×T), the adhesive effect of the intermediate portion 91 will be reduced.

[0039] The length C of the contact region 58 may be smaller than the length D of the intermediate portion 91 (C < D), or may be equal to the length D of the intermediate portion 91 (C = D). However, it is preferable that the length C of the contact region 58 is greater than the length D of the intermediate portion 91 (C > D). For example, it is preferable that the length C of the contact region 58 is at least twice the length D of the intermediate portion 91 (C ≧ 2×D). If the length C is extremely large, the length D of the intermediate portion 91 will be extremely small, and the effect of providing the adhesive member 9 will be reduced. Therefore, it is also preferable that the length C of the contact region 58 is at most four times the length D of the intermediate portion 91 (C ≦ 4×D). Assuming C + D = T, in order to satisfy C ≧ 2×D and C ≦ 4×D, the length D of the intermediate portion 91 is preferably at least one-third of the thickness T (D ≧ T / 3), and preferably at most one-fifth of the thickness T (D ≦ T / 5).

[0040] FIG. 3(a) shows the width W of the adhesive member 9 in the circumferential direction q of the cylindrical member 3 between the end face 10 and the end face 20. The adhesive member 9 between the end face 10 and the end face 20 means the intermediate portion 91 of the adhesive member 9, and the width W means the length of the intermediate portion 91 in the circumferential direction q. The length C of the contact region 58 may be smaller than the width W of the intermediate portion 91 (C < W), or may be equal to the width W of the intermediate portion 91 (C = W). However, in order to increase the adhesive strength by the adhesive member 9, it is preferable that the length C of the intermediate portion 91 is greater than the width W of the intermediate portion 91 (C > W). For example, it is preferable that the length C of the contact region 58 is at least three times the width W of the intermediate portion 91 (C ≧ 3×W). If the length C is extremely large, the effect of providing the adhesive member 9 will be reduced. Therefore, it is preferable that the length C of the contact region 58 is at most nine times the width W of the intermediate portion 91 (C ≦ 9×W), and more preferably at most six times the width W of the intermediate portion 91 (C ≦ 6×W).

[0041] The width W of the intermediate portion 91 may be greater than the length D of the intermediate portion 91 (W>C) or may be equal to the length D of the intermediate portion 91 (W=D). However, it is preferable that the width W of the intermediate portion 91 is smaller than the length L of the intermediate portion 91 (C>W). This is because the adhesive strength of the adhesive member 9 can be higher as the width W of the intermediate portion 91 is smaller and higher as the length D of the intermediate portion 91 is larger.

[0042] The difference between the inner diameter Rb and the outer diameter Ra of the cylindrical member 3 may be, for example, 1 mm or more and 4 mm or less. That is, the thickness T may be, for example, 0.5 mm or more and 2 mm or less. The length C of the contact area may be, for example, 0.5 mm or more and 1.5 mm or less. The length D of the adhesive member 9 may be, for example, 0.1 mm or more and 0.5 mm or less. The width W of the adhesive member 9 may be, for example, 0.1 mm or more and 0.5 mm or less.

[0043] As shown in FIG. 3(d), at least one of the end surface 4 and the end surface 8 of the cylindrical member 3 may be provided with projections and recesses. FIG. 4(e) is an enlarged view of an example of the end surface 4. On the end surface 4, a recess 411, a projection 421, a recess 412, and a projection 422 are arranged in this order along the circumferential direction q. Steps are provided between the recesses 411 and 412 and the projections 421 and 422. A joint 5 is provided on the recess 411. The projection 421 is provided with a recess 413 having a smaller width in the circumferential direction q and a smaller width in the radial direction r than the projection 421. The recess 412 is provided with a projection 423 having a smaller width in the circumferential direction q than the recess 412. The projection 422 is provided with a recess 414 having a smaller width in the circumferential direction q and a smaller width in the radial direction r than the projection 422. The width of the recesses 411 , 412 and the protrusions 421 , 422 on the end faces 4 , 8 in the circumferential direction r is typically greater than the thickness T of the cylindrical member 3 .

[0044] The recesses 413, 414 are provided at two locations along the circumferential direction q on the end face 4 of the cylindrical member 3. The positions of the recesses 413, 414 are desirably within an open angle range of 80° to 100° from the joint 5. The depth of the recesses 413, 414 needs to be 50% or less of the wall thickness of the metal cylindrical member 3. This is because if the depth of the recesses 413, 414 is 50% or more of the wall thickness, the strength of the material at the recesses 413, 414 may decrease.

[0045] When the cylindrical member 3 is bent and deformed from the metal plate 1 into a cylinder, providing recesses 413, 414 in the longitudinal protrusion of the metal plate has the effect of preventing the end of the cylindrical member 3, which is likely to have a large outer diameter, from being pinched in the mold.

[0046] The position of the adhesive member 9 will be described with reference to FIG. 4. In the eleventh example of FIG. 4(a), the adhesive member 9 is disposed extending from the end face 4 to the end face 8 along the joint portion 5 between the end face 10 and the end face 20. That is, the distance between the adhesive member 9 and the end face 4 and the distance between the adhesive member 9 and the end face 8 are zero. In the twelfth example of FIG. 4(b), the adhesive member 9 is disposed away from the end face 4 and the end face 8. In the thirteenth example of FIG. 4(c), the adhesive member 9 is disposed separately as the adhesive member 9a and the adhesive member 9b. The adhesive member 9a is disposed away from the end face 4 and the end face 8, the adhesive member 9b is disposed away from the end face 4 and the end face 8, and the adhesive member 9b is disposed away from the adhesive member 9a. That is, the adhesive member 9a and the adhesive member 9b are discontinuous. Both the adhesive member 9a and the adhesive member 9b have the characteristics of the adhesive member 9 described above. That is, the adhesive member 9a bonds an adhesive portion of the end face 10 of the cylindrical member 3 close to the end face 4 and an adhesive portion of the end face 20 of the cylindrical member 3 close to the end face 4. The adhesive member 9b bonds an adhesive portion of the end face 10 of the cylindrical member 3 close to the end face 8 and an adhesive portion of the end face 20 of the cylindrical member 3 close to the end face 8. The portion of the end face 10 bonded by the adhesive member 9b is disposed away from the adhesive portion of the end face 10 bonded by the adhesive member 9a. The adhesive portion of the end face 20 bonded by the adhesive member 9b is disposed away from the adhesive portion of the end face 20 bonded by the adhesive member 9a. In a 14th example not shown, the adhesive member 9a may be disposed extending from the end face 4, the adhesive member 9b may be disposed extending from the end face 8, and the adhesive members 9a and 9b may be discontinuous.

[0047] The joint 5 extends in the axial direction z of the cylindrical member 3, and the end faces 10, 20 of the joint 5 extending from the outer peripheral surface 7 to the inner peripheral surface 6 of the cylindrical member 3 are present throughout the axial direction z of the cylindrical member 3. A tapered groove that widens toward the inner peripheral surface 6 is present on the inner peripheral surface 6 side of the joint 5. The adhesive member 9 is present so as to fill all or part of the tapered groove. The tapered groove is present throughout the axial direction z of the cylindrical member 3, and it is desirable that the depth of the tapered groove is 50% or less of the thickness T of the cylindrical member 3. In other words, it is preferable that the length of the contact region 58 is 50% or more of the thickness T. In this way, by making the length of the contact region 58 sufficiently large, it is possible to suppress the possibility that the torsional strength of the cylindrical member 3 decreases or a gap occurs on the outer peripheral surface 7 side when the outer peripheral surface 7 is finish-ground.

[0048] As shown in FIG. 4(d), the cylindrical body 2 may include an additional member 79 covering the outer circumferential surface 7 of the cylindrical member 3. The additional member 79 may be metallic or non-metallic. The metallic additional member 79 may be, for example, a plating layer. The non-metallic additional member 79 may be resin, rubber, or ceramic. The additional member 79 may be a composite member in which metallic or non-metallic particles (filler) are dispersed in a matrix resin (binder resin). The non-metallic particles may be compounds such as oxides and nitrides. The additional member 79 may overlap with the adhesive member 9 in the radial direction r. In the cross-sectional view shown in FIG. 4(e), the end surface 10 and the end surface 20 are located between the adhesive member 9 and the additional member 79 in the radial direction r of the cylindrical member 3. Since a contact area 58 is provided between the adhesive member 9 and the additional member 79, the interaction between the adhesive member 9 and the additional member 79 may be suppressed.

[0049] Fig. 3(b) is a side view of metal plate 1. Fig. 3(b) shows width J of front surface 17 which becomes outer peripheral surface 7 when metal plate 1 is formed into a cylinder, width K of back surface 16 which becomes inner peripheral surface 6, thickness t of metal plate 1, and taper angle θ of end faces 10, 20. Width J, width K, thickness t, and taper angle θ can satisfy formula (1).

[0050]

number

[0051] Figure 3(c) is a cross-sectional view of the metal sheet 1 when it is formed into a cylindrical member 3. When the metal sheet 1 is bent into a cylindrical shape, tensile stress is generated on the outer peripheral surface 7 side of the metal sheet 1, and compressive stress is generated on the inner peripheral surface 6 side. The length of extension on one side of the material on the outer peripheral surface 7 side due to tensile stress is α, and the length of contraction on one side of the material on the inner peripheral surface side due to compressive stress is β. The outer peripheral length G and inner peripheral length N of the cylindrical member 3 are expressed by equations (2) and (3), respectively.

[0052]

number

[0053] Equation (4) is obtained from equations (1) and (3).

[0054]

number

[0055] In Fig. 3(a), the maximum distance between the adhesive portion 11 and the adhesive portion 22 is equal to the width W of the middle portion 91 of the adhesive member 9. The width W is the length in the circumferential direction q of the tapered groove spreading toward the inner peripheral surface. The adhesive portions 11 and 22 are each inclined with respect to the radial direction r. The distance between the position where a line imaginarily extending the adhesive portion 11 intersects with the outer peripheral surface and the position where a line imaginarily extending the adhesive portion 22 intersects with the outer peripheral surface is defined as length M.

[0056] The relationship between the outer diameter Ra, inner diameter Rb, width W, and length M of the cylindrical member 3 is expressed by the following equations (5) and (6).

[0057]

number

[0058] As shown in Figure 3(a), the angle φ formed by the bonding portions 11, 12 with respect to the radial direction r is defined. The angle φ of the bonding portions 11, 12 depends on the taper angle θ, and typically has the relationship φ = 90° - θ. The relationship between the width W, length M, length C and length D is expressed by the geometric relationships shown in formulas (7) and (8). Formula (9) can be obtained from formulas (7) and (8).

[0059]

number

[0060]

number

[0061]

number

[0062] By substituting equations (5) and (6) into equation (9), equation (11) is obtained.

[0063]

number

[0064] By substituting equations (2), (3), and (4) into equation (11), the condition that satisfies D≦C is given by equation (12), where t=T.

[0065]

number

[0066] Moreover, by substituting equations (2), (3), (4) and C=TD into equation (11), equation (13) is obtained.

[0067]

number

[0068] Using equation (13), it is possible to determine the dimensions of the material before it is molded into a cylinder that are necessary to obtain a tapered shape suitable for bonding, specifically, the depth D of the groove into which the adhesive will enter and the groove width W.

[0069] As an example using the formula, the dimensions of the material when making a cylindrical core shaft with T=1.2mm and Ra=10mm are described. In order to obtain an appropriate torsional strength when applying an instant adhesive to the joint of a cylindrical core shaft, it is known from the results of an adhesive penetration test and a torsion test that it is good to set D=0.3mm. In addition, from the experimental results, α=1.90mm and β=1.85mm were obtained. From this, J=27.83mm and θ=70° are derived, and the dimensions of the material before cylindrical molding can be specified. Typically, 60°≦θ≦80° and 10°≦φ≦30°. Since the angle between the adhesive portion 11 and the adhesive portion 22 is 2φ, the angle between the adhesive portion 11 and the adhesive portion 22 can be 20° or more and 60° or less. A cylindrical core shaft is molded based on the obtained material dimensions, and an adhesive is applied to the joint groove, making it possible to obtain a desired cylindrical core shaft with the required torsional strength.

[0070] A method for manufacturing the cylinder 2 will be described. A roughly rectangular preform metal plate is bent and the end faces are brought into contact with each other. In detail, a pair of end faces of the preform metal plate are adjusted to a tapered shape. The metal plate preform is clamped between at least a pair of concave and convex dies and clamped to obtain a U-shaped metal plate (U-bending process). The U-shaped metal plate is clamped between a pair of concave dies having a cylindrical shape corresponding to the shape of the outer peripheral surface of a metal cylindrical member, thereby forming the outer peripheral surface into a cylindrical shape (O-bending process). An adhesive is applied to the taper that widens toward the inner peripheral surface of the O-bent metal cylindrical member (application process). In this way, a cylinder is obtained.

[0071] FIG. 5(a) is a process diagram of the first manufacturing method, which will be described in more detail with reference to FIGS.

[0072] In the chamfer forming step S01 in FIG. 5(a), a chamfer is formed on the metal plate as a raw material. FIG. 6(a) shows a preform metal plate 1a. The preform metal plate 1a is a thin-walled metal plate having contact end faces 10a, 20a, end faces 14a, 18a, a front surface 17, and a back surface 16. The end faces 10a, 20a are end faces that come into contact with each other to form a contact area 58 when formed into a cylindrical member 3, and extend in the axial direction z after cylindrical forming. The end face 14a has convex parts 421, 422 formed with a concave part therebetween, and the end face 18a is also similar. The material of the preform metal plate 1a can be a material that can be cold-bent and has a predetermined strength, such as SPCC (cold-rolled steel plate), stainless steel, aluminum alloy, etc., but is not limited thereto. The preform metal plate 1a is manufactured by press-cutting a strip-shaped material, but is not limited thereto, and may be manufactured by machining such as wire electric discharge machining.

[0073] FIG. 7(a) is a diagram showing the operation of the mold and the molded product in the chamfer forming step S01. The process of clamping the preform metal sheet 1a between the chamfer forming upper die 26 and the chamfer forming lower die 25 is shown. The chamfer forming upper die 26 is arranged so that the convex strips 261 and 262 on the molding surface are located near the convex parts 421 and 422 of the end faces 14a and 18a of the metal sheet 1a. The molding surface of the chamfer forming lower die 25 is flat. The chamfer forming upper die 26 and the chamfer forming lower die 25 are made of hardened steel or cemented carbide, and the convex strips 261 are V-shaped with a pointed top or U-shaped with a rounded top. After clamping until the gap between the chamfer forming upper die 26 and the chamfer forming lower die 25 reaches a predetermined thickness, the preform metal sheet 1b is taken out and has recesses 414 and 413 formed therein. Fig. 6(b) is a diagram of preformed metal sheet 1b, in which recesses 414, 413 are formed in protrusion 421 (see Fig. 6(a)) of end face 14. It is desirable to adjust the length in the width direction of end face 14b of preformed metal sheet 1b to 85 to 90% of the outer circumferential length of metal cylindrical member 3, taking into account the elongation of the material when bending into a cylinder.

[0074] Fig. 6(d) is an enlarged view of part B in Fig. 6(b). The recesses 413 and 414 are inclined from the upper surface of the metal plate to the side end face. The distance of the recess 413 from the end face 20a is c, the distance from the end face is d, the width of the recess 413 is e, the chamfer depth is f, the amount of protrusion from the side end face is g, the width of the protrusion is h, and the plate thickness is t.

[0075] The distance c from the end face 20c is preferably approximately one-fourth the width direction length of the end face 14b of the preform metal plate 1b. In other words, it is desirable to set the distance c so that the recesses 413, 414 in the metal cylindrical member 3 are positioned at an angle of 80° to 100° from the joint 5.

[0076] It is also preferable that the distance d from the side end face is equal to or less than the protrusion amount g, the chamfer width e is equal to or less than half the protrusion width h, and the chamfer depth f is equal to or less than half the plate thickness t. If chamfering is performed beyond these dimensions, the chamfering will cause more internal stress to accumulate in the material than necessary, making bending the protrusion difficult. This will also lead to a deterioration in roundness.

[0077] Next, the end surface taper forming step S02 in Fig. 5(a) will be explained. In the end surface taper forming step S02, before forming the metal sheet into a cylindrical shape, the metal sheet is clamped between a pair of dies so that it is warped in the opposite direction to the bending direction, and in this state, the end surface of the metal sheet is cut off to form a tapered shape on the end surface of the metal sheet. This time, an example of a single process is shown, but it is not limited to this, and a method of forming the end surface by clamping it with a pair of dies can also be used.

[0078] Fig. 7(b) is a diagram showing the operation of the mold and the molded product in the end face taper forming step S02. The process shows how the chamfered preform metal sheet 1b is sandwiched between the taper forming upper die 28 and the taper forming lower die 29, clamped, and warped in the opposite direction to the bending direction, by cutting off the end face to form a tapered shape on the end face of the preform metal sheet 1b. The taper forming upper die 28 and the taper forming lower die 29 are made of hardened steel or cemented carbide, and the taper forming upper and lower dies are provided with a taper, and the size of the tapered groove on the inner peripheral surface side of the metal cylindrical member 3 is adjusted by adjusting the angle of this taper. The preform metal sheet 1c taken out has a taper formed therein.

[0079] Fig. 6(c) is a diagram showing the preform metal plate 1c, the end faces of which have been cut off in Fig. 9, flattened to a flat surface. Tapers are formed on the end faces 10a and 20a.

[0080] The metal plate 1 thus prepared, which has the characteristics of a preform metal plate 1c (tapered preform metal plate), is put into a forming process.

[0081] Next, the U-bending process S03 in Fig. 5(a) will be described. The U-bending process S03 is made up of a step of bending the ends and a step of bending the center of a flat plate sandwiched between a concave mold and a convex mold. The number of steps is shown as an example in which the end bending process is three steps, the first to third U-bending processes, and the center bending process is one step, the fourth U-bending process, but it is not limited to this and the number of steps can be increased or decreased according to requirements.

[0082] 8(a) to 8(d) are diagrams showing the U-bending process S03 using cross-sectional views of the die and formed product perpendicular to the axial direction of the target metal cylindrical member 3. The end bending process is performed so that the bending width increases stepwise from the end of the metal sheet 1. This is intended to make it easier to insert the material into the die in the subsequent O-bending process.

[0083] Fig. 8(a) is a cross-sectional view of a die-formed product in the first U-bending process. This is a process in which metal sheet 1 is sandwiched between U-bending first upper die 31 and U-bending first lower die 35 and pressed. U-bending first upper die 31 has an axial groove, with first upper die groove flat portion 32 extending axially in the center of the axial groove and first upper die groove cylindrical surface portion 33 extending at both ends. The width of first upper die groove flat portion 32 is defined as m1. m1 varies depending on the number of steps in the U-bending process. The radius of first upper die groove cylindrical surface portion 33 is defined as R1.

[0084] The U-bending first lower die 35 has axial ridges, which are formed by a first lower die ridge flat surface portion 36 extending in the axial direction, and a first lower die ridge cylindrical surface portion 37 extending from both ends. The width of the first lower die ridge flat surface portion 36 is m1, which is equal to the width of the upper die groove flat surface portion 32. The radius of the first lower die ridge cylindrical surface portion 37 is R1-t.

[0085] In the first U-bending process, the metal sheet 1 sandwiched between the U-bending first upper die 31 and the U-bending first lower die 35 is bent from its end to obtain a U-bending first intermediate product 40. The radii of the cylindrical surface portion formed at the end of the U-bending first intermediate product 40 after it is removed from the die are designated as r1 and r1-t.

[0086] 8(b) shows the second U-bending process, in which the U-bending first intermediate product 40 is exchanged and pressed between a U-bending second upper die 41 and a U-bending second lower die 45. The U-bending second upper die 41 has an axial groove, with a second upper die groove flat portion 42 extending axially in the center of the axial groove and second upper die groove cylindrical surface portions 43 extending at both ends. The width of the second upper die groove flat portion 42 is m2. m2 varies depending on the number of steps in the U-bending process. The radius of the second upper die groove cylindrical surface portion 43 is R2.

[0087] The U-bending second lower die 45 has axial ridges, and the axial ridges are formed by the second lower die ridge flat portion 46 extending in the axial direction, and the second lower die ridge cylindrical surface portion 47 extending from both ends. The width of the second lower die ridge flat portion 46 is m2, which is equal to the width of the second upper die groove flat portion 42. The radius of the second lower die ridge cylindrical surface portion 47 is R2-t.

[0088] In the second U-bending process, the U-bent first intermediate product 40 sandwiched between the U-bending second upper die 41 and the U-bending second lower die 45 is bent from its end to obtain a U-bent second intermediate product 50. The radii of the cylindrical surface portion formed at the end of the U-bent second intermediate product 50 after being removed from the die are designated as r1 and r1-t.

[0089] 8(c) shows the third U-bending process, in which the U-bending second intermediate product 50 is exchanged and pressed between a U-bending third upper die 51 and a U-bending third lower die 55. The U-bending third upper die 51 has an axial groove, with a third upper die groove flat portion 52 extending axially in the center of the axial groove and a third upper die groove cylindrical surface portion 53 extending at both ends. The width of the third upper die groove flat portion 52 is m3. m3 varies depending on the number of steps in the U-bending process. The radius of the third upper die groove cylindrical surface portion 53 is R3.

[0090] The U-bending third lower die 55 has axial ridges, which are formed by a third lower die ridge flat portion 56 extending in the axial direction, and third lower die ridge cylindrical surface portions 57 extending from both ends. The width of the third lower die ridge flat portion 56 is m3, which is the same as the third upper die groove flat portion 52. The radius of the third lower die ridge cylindrical surface portion 57 is R3-t.

[0091] In the third U-bending process, the U-bent second intermediate product 50 sandwiched between the U-bending third upper die 51 and the U-bending third lower die 55 is bent from its end to obtain a U-bent third intermediate product 60. The radii of the cylindrical surface portion formed at the end of the U-bent third intermediate product 60 after being removed from the die are designated as r1 and r1-t.

[0092] FIG. 8(d) shows the fourth U-bending process, which is a central bending process, in which the U-bending third intermediate product 60 is sandwiched between a fourth U-bending upper die 61 and a fourth U-bending lower die 65 after die replacement, and pressurized. A fourth upper die cylindrical surface portion 62 extends in the axial direction at the center of the fourth U-bending upper die 61, and the radius of the fourth upper die cylindrical surface portion 62 is R4. The end of the fourth upper die cylindrical surface portion 62 is smoothly chamfered as a fourth upper die chamfered portion 63, which prevents the U-bending third intermediate product 60 from being scratched. A fourth lower die convex stripe portion 67 having a fourth lower die convex stripe cylindrical surface portion 66 extends in the axial direction at the center of the fourth U-bending lower die 65. The radius of the fourth lower die convex stripe cylindrical surface portion 66 is R4-t.

[0093] The fourth U-bending process produces a final U-bend product 70. The end and center of the final U-bend product 70 are cylindrical, and the area between the end and center is flat. The width n of the fourth lower die protruding streak portion 67 is set between a lower limit dimension that will not break during bending deformation and an upper limit dimension that will not interfere with the side of the fourth lower die protruding streak portion when the opening of the third intermediate U-bend product 60 narrows due to bending deformation. The radii of the cylindrical surface portion formed in the center of the final U-bend product 70 after it is removed from the mold are r4 and r4-t.

[0094] Next, the O-bend forming step S04 in Fig. 5(a) will be described. The O-bend forming step S04 is performed using the U-bend final formed product 70.

[0095] 8(e) to (i) are diagrams illustrating the O-bending process S04 using diagrams of the mold and the formed product.

[0096] FIG. 8(e) shows the first O-bending process, and is a diagram of the state in which the final U-bending product 70 is placed between the O-bending first upper die 71 and the O-bending first lower die 75. In the center of the O-bending first upper die 71, a groove having an O-bending first upper die cylindrical surface portion 72 extends in the axial direction. Furthermore, in the center of the O-bending first lower die 75, a groove having an O-bending first lower die cylindrical surface portion extends in the axial direction. The ends of the O-bending first upper die cylindrical surface portion 72 and the O-bending first lower die cylindrical surface portion are smoothly chamfered to form the O-bending first upper die chamfered portion 73 and the O-bending first lower die chamfered portion 77. The O-bending first upper die chamfered portion 73 and the O-bending first lower die chamfered portion 77 can prevent the final U-bending product 70 from being scratched during the deformation process.

[0097] 8(f) also shows the first O-bending process and is a diagram showing a state where clamping of the O-bending first upper die 71 and the O-bending first lower die 75 is completed. The radius of the O-bending first upper die 71 and the O-bending first lower die 75 is R5.

[0098] The first O-bending process produces an O-bending intermediate product 80. The inner peripheral surface of the O-bending intermediate product 80 has no gap, but the outer peripheral surface has a gap 78 due to the difference in inner and outer peripheral length. The distance between the O-bending first upper die 71 and the O-bending first lower die 75 is adjusted so that the O-bending intermediate product 80 does not fill the space between the O-bending first upper die chamfered portion 73 and the O-bending first lower die chamfered portion 77. Therefore, the O-bending intermediate product 80 has a vertically elongated flat cross-sectional shape rather than a cylindrical shape. When the O-bending intermediate product 80 is removed from the mold, the gap 78 expands due to elastic recovery, resulting in an O-bending intermediate product 85. The radii of the cylindrical surface portion formed in the center of the O-bending intermediate product 85 are r5 and r5-t.

[0099] 8(g) shows the second O-bending process, and is a diagram showing the state in which an O-bending intermediate formed product 85 is placed between an O-bending second upper die 81 and an O-bending second lower die 83 after die exchange. A groove having an O-bending second upper die cylindrical surface portion 82 extends in the axial direction at the center of the O-bending second upper die 81. Furthermore, a groove having an O-bending second lower die cylindrical surface portion 84 extends in the axial direction at the center of the O-bending second lower die 83.

[0100] The width of the O-bend intermediate molded product 85 is set smaller than the opening width of the O-bend second upper die cylindrical surface portion 82 and the O-bend second lower die cylindrical surface portion 84, so that the O-bend intermediate molded product 85 does not protrude between the O-bend second upper die 81 and the O-bend second lower die 83 due to bending. The radius of the O-bend second upper die cylindrical surface portion 82 and the O-bend second lower die cylindrical surface portion 84 is R6.

[0101] 8(h), the O-bending second upper die 81 and the O-bending second lower die 83 are clamped together, and the deformation of the O-bending intermediate formed product 85 progresses to become an O-bending intermediate formed product 86. At this point, the formed product has no gaps on its outer periphery, and reaches a state in which an O-bending intermediate formed product opening 87 is formed on its inner periphery. At this point, the O-bending second upper die 81 and the O-bending second lower die 83 have not yet come into contact with each other.

[0102] Fig. 8(i) shows the state in which the O-bending second upper die 81 and the O-bending second lower die 83 are in contact. The O-bending intermediate product 86 has a reduced O-bending intermediate product opening 87 and a contact area 58 is generated on the outer circumferential surface side. A final O-bending product 88 is obtained by the second O-bending process. The final O-bending product 88 is removed from the die and becomes the metal cylindrical member 3. The radius of the metal cylindrical member 3 becomes r0, which is the target value for the transport roller, due to elastic recovery.

[0103] Even if elastic recovery occurs, the contact regions 58 do not separate. This is because compressive residual stress is generated in the contact regions 58 by the O-bending process, so that the contact regions 58 do not separate after removal from the mold.

[0104] Depending on the conditions, slight deflection may occur in the O-bend final formed product 88 at the position where the contact region 58 and the O-bend second lower die cylindrical surface portion 84 intersect, and the O-bend second lower die cylindrical surface portion 84 may separate from the O-bend final formed product 88. In such cases, after bending deformation, the outer peripheral surface 7 of the metal cylindrical member 3 may be ground as a finishing process.

[0105] After the second O-bending process is completed, the O-bending final formed product 88 is taken out of the mold, and the metal cylindrical member 3 is obtained. The metal cylindrical member 3 is covered with the additional member 79, and then the adhesive that becomes the adhesive member 9 is applied to the tapered groove formed on the inner peripheral surface side, and the adhesive is hardened to obtain the cylindrical body 2. FIG. 7(c) shows an example of the adhesive process. A nozzle 910 is inserted from one opening of the cylindrical member 3, and adhesive is discharged from the nozzle 910 and applied to the joint 5 to form the adhesive member 9a shown in FIG. 4(c). A nozzle 920 is inserted from the other opening of the cylindrical member 3, and adhesive is discharged from the nozzle 920 and applied to the joint 5 to form the adhesive member 9b shown in FIG. 4(c). Here, since two nozzles 910 and 920 are used, the adhesive members 9a and 9b can be formed simultaneously. The adhesive members 9a and 9b may be formed sequentially with one nozzle.

[0106] Next, the correlations between R1 to R6 and r0 to r5 are shown. First, R6 takes into account the elastic recovery of bending and satisfies formula 1. Formula 1 R6 = k6r0 where k6≦1

[0107] k6 is a coefficient of elastic recovery, and varies depending on the material and shape of the metal cylindrical member 3. k6 is determined by previously determining the ratio of the radius of the O-bending second upper die cylindrical surface portion 82 and the O-bending second lower die cylindrical surface portion 84 to the radius of the bent metal cylindrical member 3.

[0108] Next, formula 2 is satisfied so that the O-bend intermediate molded product 85 does not protrude between the O-bend second upper die 81 and the O-bend second lower die 83 . Formula 2 R6>r5

[0109] Next, R5 takes elastic recovery into account and satisfies Eq. Formula 3 R5 = k5r5 where k5≦1

[0110] k5 is a coefficient of elastic recovery, and varies depending on the material and shape of the metal cylindrical member 3. k5 is determined by determining in advance the ratio of the radius of the O-bend first upper die cylindrical surface portion 72 and the radius of the O-bend first lower die cylindrical surface portion 76 to the radius of the O-bend intermediate formed product 85.

[0111] Next, formula 4 is satisfied so that the final U-shaped product 70 does not protrude between the O-shaped first upper die 71 and the O-shaped first lower die 75 . Formula 4 R5>r4

[0112] Next, R4 considers elastic recovery and satisfies Eq. 5. Formula 5 R4 = k4r4 where k4≦1

[0113] k4 is a coefficient of elastic recovery, and varies depending on the material and shape of the metal cylindrical member 3. k4 is determined by previously determining the ratio of the radius of the U-bending fourth upper die 61 and the U-bending fourth lower die 65 to the radius of the U-bending final formed product 70.

[0114] Next, the U-bending third intermediate formed product 60 is placed between the U-bending fourth upper die 61 and the fourth lower die protruding rib portion in a stable position, so that formula 6 is satisfied so that bending is performed. Formula 6 R4 <r3

[0115] Next, the following formula is satisfied in the first to third U-bending processes. Equation 7 R1=R2=R3 Formula 8 r1=r2=r3

[0116] Next, R1 takes elastic recovery into account and satisfies Equation 9. Formula 9 R1 = k1r1 where k1≦1

[0117] Equation 10 is satisfied based on the process order. Formula 10 m1>m2>m3

[0118] Furthermore, m1, m2, and m3 are determined so that the end faces 10, 20 of the U-bent third intermediate product 60 do not come into contact with the fourth lower die protruding ridge portion during bending in the subsequent fourth U-bending process.

[0119] In this manner, the cylindrical body 2 can be manufactured.

[0120] Fig. 5(b) is a process diagram of the second manufacturing method, which will be described with reference to Fig. 9. In the second manufacturing method, a cylindrical member is continuously manufactured from a metal strip wound in a coil shape. Fig. 9 is a schematic diagram that omits the mold and molding device and only shows the shape of the formed product in order to explain the second manufacturing method, and shows the state from metal strip 101 to obtaining metal cylindrical member 3.

[0121] In the slot forming step S11, positioning holes 102 and chamfering grooves 103 are formed in a continuous metal strip 101, which is the raw material.

[0122] In the preform metal plate punching step S12, the metal strip 101 is punched at positions corresponding to the positioning holes 102 to obtain a preform metal plate 1d. The preform metal plate 1d is connected to a holding frame 104 via a connection part 105 that can be easily cut later. Furthermore, this punching step forms the chamfer groove 103 formed in step S11 so as to be located on a side end surface of the preform metal plate 1d.

[0123] In the end face taper forming process S13, a taper shape is formed on the abutting end face of the preform metal sheet 1d. The abutting end face is cut off while the preform metal sheet 1d is clamped and pressed by a pair of dies in the direction opposite to the bending direction of the cylindrical molding, thereby forming a taper shape on the end face of the metal sheet. This time, an example of one process is shown, but this is not limited to this, and a method of forming the end face by clamping and pressing with a pair of dies is also considered. In this manner, the metal sheet 1 is formed.

[0124] In the U-bending process S14, a first intermediate U-bend product 40, a second intermediate U-bend product 50, a third intermediate U-bend product 60, and a final U-bend product 70 are obtained through three end bending processes and one central bending process.

[0125] In the O-bend forming process S15, an intermediate O-bend product 80 and a final O-bend product 88 are obtained by a two-stage O-bend forming process.

[0126] In the cutting step S16, the connection portion 105 is cut to separate the final O-shaped product 88 from the holding frame 104, thereby obtaining a cylindrical product 89.

[0127] In the grinding step S17, the outer circumferential surface of the cylindrical molded product 89 separated from the holding frame 104 is ground to obtain the cylindrical member 3.

[0128] In the coating step S18, the cylindrical member 3, the outer circumferential surface of which has been ground and finished, is coated with the additional member 79.

[0129] In the bonding step S19, an adhesive is applied to the tapered portion on the inner peripheral surface side of the cylindrical member 3.

[0130] In this manner, the cylindrical body 2 can be manufactured.

[0131] The cylinder 2 can be used in various devices. Devices equipped with the cylinder 2 can include at least one of mechanical parts, optical parts, and electronic parts. The mechanical parts can be, for example, motors and gears, the optical parts can be, for example, lenses, mirrors, image sensors, and displays, and the electronic parts can be, for example, processors and memories. The various devices can be electronic devices such as computers, and transportation equipment such as vehicles, ships, and aircraft. The various devices can also be medical equipment such as radiological diagnostic devices, ultrasonic diagnostic devices, and endoscopes, office equipment such as printers and scanners, and industrial equipment such as semiconductor manufacturing equipment and robots. The cylinder 2 of this embodiment can be used not only as a part in complex devices equipped with mechanical parts, optical parts, electronic parts, and the like, but also as a pipe for various uses in food, clothing, and shelter.

[0132] Fig. 10(a) is a perspective view showing a schematic view of the inside of a printing device 1010. The printing device 1010 includes a transport roller 1012. The printing device 1010 includes a motor 1014 and a mechanical part 1015. The mechanical part 1015 is a transmission mechanism that transmits the power of the motor 1014 to the transport roller 1012, and is fixed to the transport roller 1012. The rotation of the motor 1014 is transmitted to the transport roller 1012 via the mechanical part 1015, and the transport roller 1012 rotates around the central axis of a cylindrical member 3 included in the transport roller 1012 as the rotation center.

[0133] As shown in FIG. 4(d), the transport roller 1012 has an additional member 79 attached to the outer periphery of the cylindrical member 3. In this example, the additional member 79 is a ceramic layer for increasing the coefficient of friction to facilitate transport of the recording medium. The recording medium, such as paper, is transported by the transport roller 1012. Ink is sprayed by an ink head 1016.

[0134] In an inkjet printer that ejects ink onto a recording medium such as paper to record information such as characters and images, rollers for transporting the paper are used in various places. Among them, the transport roller is a roller for transporting the recording paper to a predetermined printing position by rotating, and extends horizontally and in a direction perpendicular to the paper feed direction of the paper feed unit, and has a cylindrical shape. The transport roller is rotatably supported by a pair of approximately U-shaped bearings (not shown) provided in the transport section, and rotates by the drive of the drive section. The transport roller determines the printing accuracy, so it is required to have a high outer diameter, roundness, runout accuracy, and durability. The transport roller that transports the paper needs to transport the paper with high positioning accuracy. To achieve this, the transport roller is required to have high roundness, torsional strength, and durability.

[0135] Metal round bars have been used as roller materials to satisfy these requirements, but they are heavy and expensive, so there are issues with these materials and there are efforts being made to reduce their weight and cost.

[0136] By using the above-mentioned cylindrical body 2 as the transport roller 1012, it is possible to ensure torsional strength and durability while achieving weight reduction and cost reduction.

[0137] Here, an example has been given in which the cylindrical body 2 is applied to a transport roller of an inkjet printer as a printing device, but the cylindrical body 2 can also be applied to various rollers and drums of a laser beam printer as a printing device.

[0138] 10(b) shows a camera system 1040 including an optical device 1020 and an imaging device 1030. The optical device 1020 may include, for example, a lens hood 1023, a lens barrel 1022, and a lens (not shown). The cylindrical body 2 may be applied to the lens hood 1023 or the lens barrel 1022.

[0139] FIG. 10(c) shows a production system 1050 including a robot 1060, a controller 1080 for controlling the robot 1060, and a belt conveyor 1090 for transporting an article. The robot 1060 includes a robot arm 1061, a joint 1062, and a robot hand 1063. The robot 1060 grasps a workpiece W2 with the robot hand 1063 and assembles the workpiece W2 to the workpiece W1. The above-mentioned cylinder 2 can be used as an exterior body of the robot arm 1061. The belt conveyor 1090 includes a transport roller 1092 and a belt 1091. The belt conveyor 1090 transports the workpiece W1. The above-mentioned cylinder 2 can be used for the transport roller 1092.

[0140] The above-described embodiments can be modified as appropriate without departing from the technical spirit of the present invention. For example, multiple embodiments can be combined. In addition, some features of at least one embodiment can be deleted or replaced. In addition, new features can be added to at least one embodiment.

[0141] The disclosure of this specification includes not only what is explicitly described in this specification, but also all matters that can be understood from this specification and the drawings attached hereto. For example, any combination of each described matter is also the disclosure of this specification. For example, if there is a description that "A is equal to or greater than B" and a description that "C is equal to or less than D", then the form "A is equal to or greater than B and C is equal to or less than D" is the disclosure of this specification. In this specification, "A is equal to or greater than B" (A is any element, B is any index) means "A is equal to B or A is greater than B". "C is equal to or less than D" (C is any element, D is any index) means "C is equal to D or C is less than D (less than C)". Furthermore, the disclosure of this specification includes the complement of each concept described in this specification. In other words, if there is a description in this specification that "E is F", for example, even if the description of the case where "E is not F" is omitted, this specification can be said to disclose the case where "E is not F". This is because when it is stated that "E is F," it is assumed that the case where "E is not F" is also taken into consideration. [Explanation of symbols]

[0142] 10 End face 20 End face 1 metal plate 3 Cylindrical members 9 Adhesive materials 11 Adhesive part 22 Adhesive part 13 Contact area 24 Contact area 2. Cylinder

Claims

1. A cylindrical member formed by shaping a metal plate having a first end face and a second end face into a cylindrical shape such that the first end face and the second end face face each other, and a non-metallic adhesive member that adheres the first end face and the second end face, the distance between the boundary between the first end face and the inner peripheral surface of the cylindrical member and the boundary between the second end face and the inner peripheral surface of the cylindrical member is greater than the distance between the boundary between the first end face and the outer peripheral surface of the cylindrical member and the boundary between the second end face and the outer peripheral surface of the cylindrical member, the adhesive member is provided between a first portion of the first end face and a second portion of the second end face, and the first portion and the second portion are non-parallel, the adhesive member is a cylindrical body adhered to a part of the inner peripheral surface of the cylindrical member.

2. A third portion of the first end face and a fourth portion of the second end face are in contact, and the length of the contact region where the first end face and the second end face are in contact with each other in the radial direction of the cylindrical member is 50% or more of the thickness of the cylindrical member. The cylindrical body according to Claim 1.

3. A cylindrical member formed by shaping a metal plate having a first end face and a second end face into a cylindrical shape such that the first end face and the second end face face each other, and a non-metallic adhesive member that adheres the first end face and the second end face, the distance between the boundary between the first end face and the inner peripheral surface of the cylindrical member and the boundary between the second end face and the inner peripheral surface of the cylindrical member is greater than the distance between the boundary between the first end face and the outer peripheral surface of the cylindrical member and the boundary between the second end face and the outer peripheral surface of the cylindrical member, the adhesive member is provided between a first portion of the first end face and a second portion of the second end face, the adhesive member is adhered to a part of the inner peripheral surface of the cylindrical member, and a third portion of the first end face and a fourth portion of the second end face are in contact. The cylindrical body.

4. The cylindrical body according to any one of Claims 1 to 3, wherein in the radial direction of the cylindrical member, the adhesive member and the contact region where the first end face and the second end face are in contact with each other are arranged side by side.

5. The cylindrical body according to any one of Claims 1 to 4, wherein the length of the contact region where the first end face and the second end face are in contact with each other in the radial direction of the cylindrical member is greater than the length of the adhesive member in the radial direction between the first end face and the second end face.

6. The cylindrical body according to Claim 5, wherein the length of the contact region is 2 times or more and 4 times or less the length of the adhesive member.

7. The length of the contact area is greater than the width of the adhesive member between the first end face and the second end face in the circumferential direction of the cylindrical member, the cylindrical body according to claim 5 or 6.

8. The width of the adhesive member between the first end face and the second end face in the circumferential direction of the cylindrical member is smaller than the length of the adhesive member between the first end face and the second end face in the radial direction of the cylindrical member, the cylindrical body according to any one of claims 1 to 7.

9. The cylindrical body is provided with a non-metallic additional member covering the outer peripheral surface of the cylindrical member, and in the radial direction of the cylindrical member, the first end face and the second end face are located between the adhesive member and the additional member, the cylindrical body according to any one of claims 1 to 8.

10. The difference between the inner diameter and the outer diameter of the cylindrical member is 1 mm or more and 4 mm or less, the length of the contact area is 0.5 mm or more and 1.5 mm or less, the length of the adhesive member is 0.1 mm or more and 0.5 mm or less, and the width of the adhesive member is 0.1 mm or more and 0.5 mm or less, the cylindrical body according to claim 7.

11. The adhesive member is a cured resin adhesive or an inorganic adhesive, the cylindrical body according to any one of claims 1 to 10.

12. The cylindrical member has a metal-containing portion containing a metal which is any one of iron, copper, magnesium or aluminum, and the adhesive member is in contact with the metal-containing portion or a film of a compound of the metal covering the metal-containing portion, the cylindrical body according to any one of claims 1 to 11.

13. The cylindrical member has a third end face and a fourth end face in the axial direction of the cylindrical member, The distance between the third end face and the fourth end face is greater than the outer diameter of the cylindrical member, the cylindrical body according to any one of claims 1 to 12.

14. The adhesive member is arranged away from the third end face and the fourth end face, the cylindrical body according to claim 13.

15. The adhesive member includes a first adhesive member and a second adhesive member, The first adhesive member and the second adhesive member are discontinuous, The first adhesive member is arranged away from the third end face, and the second adhesive member is arranged away from the fourth end face, the cylindrical body according to claim 13.

16. At least one of the third end face and the fourth end face of the cylindrical member is provided with irregularities, the cylindrical body according to any one of claims 13 to 15.

17. A cylindrical body according to any one of claims 1 to 16, and at least one of mechanical parts, optical parts, and electronic parts, a device comprising the same.

18. The device according to claim 17, further comprising a mechanical device fixed to the cylindrical body, the mechanical device being provided so that the cylindrical body rotates about the axis of the cylindrical member as a rotation center.

19. The device according to claim 17 or 18, wherein the cylindrical body is a transport roller for transporting an article.

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