Cap and method of manufacturing a cap

Abstract

A cap (1) includes a cap main body (11) having a top plate portion (21) and a cylindrical skirt portion (22) provided to the top plate portion (21), a seal member (12) provided to the cap main body (11) opposite to the top plate portion (21) and separate from the cap main body (11), a plurality of locking portions (31) provided in the circumferential direction of the skirt portion (22), protruding toward the inside of the radius of the skirt portion (22) and supporting the seal member (12), a plurality of small diameter portions (35a) provided between the locking portions (31) of the skirt portion (22) and the top plate portion (21) and provided on the top plate portion (21) side of the locking portions (31) in the axial direction, and a large diameter portion (35b) provided in the circumferential direction adjacent to the small diameter portions (35a) and having a diameter larger than the diameter of an inscribed circle of the small diameter portions (35a).

Description

TECHNICAL FIELD

[0001] The present application relates to a lid for a can container that seals and houses a beverage, and a manufacturing method of the lid. BACKGROUND

[0002] Conventionally, a lid that seals a mouth portion of a can container adopts a structure in which a sealing member composed of a resin material that is in close contact with the mouth portion on an inner surface of a lid main body. In addition, as such a lid, in Japanese Patent Application Publication No. 2004-217295 and Japanese Patent Application Publication No. 2017-178421, a technique is disclosed in which a lid main body and a sealing member are not bonded in order to reduce the lid opening torque at the time of opening the lid.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT DOCUMENTS

[0005] Patent Document 1: Japanese Patent Application Publication No. 2004-217295

[0006] Patent Document 2: Japanese Patent Application Publication No. 2017-178421 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] In the above-described lid, the sealing member is caught in the vent slit that protrudes to the inner side of the skirt portion, and is prevented from falling off. However, in the case where the pressure in the container is negative, there is a risk that the sealing member will easily stick to the container mouth portion side, and that the sealing member will fall off from the lid main body at the time of opening the lid.

[0009] On the contrary, in order to sufficiently catch the sealing member, when the vent slit is formed deep to the inner side in the radial direction, there is a risk that a crack will occur at the end portion of the vent slit. In addition, it is considered to provide a recess that protrudes to the inner side of the skirt portion without a gap in the skirt portion. However, even in the case where the sealing member is caught by the recess provided in the skirt portion, when the recess is formed too deep, there is a risk that the skirt portion will be damaged.

[0010] Here, an object of the present application is to provide a lid in which the skirt portion is not damaged, and in which the falling off of the sealing member can be reliably prevented, and a manufacturing method of the lid.

[0011] TECHNICAL SOLUTION FOR SOLVING THE PROBLEMS

[0012] The lid according to one embodiment of the present application includes: a lid main body having a top plate portion and a cylindrical skirt portion provided to a peripheral portion of the top plate portion; a seal member provided to the lid main body so as to oppose the top plate portion; a plurality of locking portions provided in a circumferential direction of the skirt portion, protruding toward an inner side in a radial direction of the skirt portion, and supporting the seal member; a plurality of small-diameter portions provided between the locking portions of the skirt portion and the top plate portion, and provided on the top plate portion side of the locking portions in an axial direction; and a plurality of large-diameter portions provided so as to be adjacent to the small-diameter portions in the circumferential direction, and having an inscribed circle diameter larger than an inscribed circle diameter of the plurality of small-diameter portions.

[0013] The manufacturing method of the lid according to one embodiment of the present application includes: arranging a molded piece in a first tool, the molded piece having a top plate portion and a skirt portion integrally formed in the top plate portion via a corner portion in a circular ring shape and a curved surface shape, the first tool having a plurality of first protrusions in an outer peripheral surface, and having a plurality of large-diameter portion molding portions adjacent to the first protrusions in an axial direction and a plurality of small-diameter portion molding portions provided to the large-diameter portion molding portions in a circumferential direction; relatively rotating a second tool having a second protrusion arranged between adjacent first protrusions of the first tool and the first tool, and making the second protrusion enter between the adjacent first protrusions, and forming a plurality of recesses, a plurality of small-diameter portions, and a plurality of large-diameter portions in the skirt portion.

[0014] Effects of the Invention

[0015] According to the present application, a lid capable of preventing a seal member from falling off without damaging a skirt portion and a manufacturing method of the lid can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 FIG. 1 is a cross-sectional view schematically showing a structure of a lid and a can container according to one embodiment of the present application.

[0017] Figure 2 FIG. 2 is a perspective view showing a structure of the lid.

[0018] Figure 3 FIG. 3 is a side view showing a structure of the lid.

[0019] Figure 4 FIG. 4 is a cross-sectional view showing a structure of the lid.

[0020] Figure 5 FIG. 5 is an enlarged cross-sectional view showing a structure of the lid.

[0021] Figure 6 FIG. 6 is an enlarged cross-sectional view showing a structure of the lid.

[0022] Figure 7 FIG. 7 is a cross-sectional view showing a structure of the lid.

[0023] Figure 8 This is an explanatory diagram showing an example of how the lid is manufactured.

[0024] Figure 9 This is an explanatory diagram showing an example of how the lid is manufactured.

[0025] Figure 10 This is an explanatory diagram showing an example of the manufacturing apparatus for the cover.

[0026] Figure 11 This is a cross-sectional view showing an example of the manufacturing apparatus for the cover.

[0027] Figure 12 This is a cross-sectional view showing an example of the manufacturing apparatus for the cover.

[0028] Figure 13 This is a cross-sectional view showing an example of the manufacturing apparatus for the cover.

[0029] Figure 14 This is a perspective view showing the structure of the first tool of the manufacturing apparatus.

[0030] Figure 15 It is a three-dimensional view showing the structure of the first tool.

[0031] Figure 16 A three-dimensional view showing the structure of the first tool is provided. Detailed Implementation

[0032] The following adopts Figures 1 to 16 This invention describes a cover 1, a method for manufacturing the cover 1, and a manufacturing apparatus 200 according to one embodiment of the present invention.

[0033] Figure 1 This is a schematic cross-sectional view illustrating the structure of the lid 1 and the container 100 according to one embodiment of the present invention. Figure 2 This is a perspective view showing the structure of cover 1. Figure 3 This is a side view showing the structure of cover 1. Figure 4 This is a cross-sectional view showing the structure of cover 1. Figure 5 This is an enlarged view showing the structure of cover 1, i.e. Figure 4 A sectional view of the middle V section. Figure 6 This is an enlarged view showing the structure of cover 1, i.e. Figure 4 Sectional view of section VI. Figure 7 The structure of cover 1 is based on Figure 4 The cross-sectional view shown along line VII-VII.

[0034] Figure 8 as well as Figure 9 This is an explanatory diagram showing an example of the manufacturing method of cover 1. Figure 10 This is an explanatory diagram showing an example of the structure of the manufacturing apparatus 200 for cover 1. Figures 11 to 13This is a cross-sectional view showing an example of the manufacturing apparatus 200 in different locations. Figure 14 This is a perspective view showing the structure of the first tool 211 used in the manufacturing apparatus 200. Figure 15 The structure of the first tool 211 is compared with... Figure 11 A magnified stereoscopic image showing the same pose. Figure 16 The structure of the first tool 211 is compared with... Figure 11 Three-dimensional images shown in different poses.

[0035] like Figure 1 As shown, the opening 110 of the container 100 is sealed by tightening the lid 1 to cover it. First, using... Figure 1 Description of container 100.

[0036] like Figure 1 As shown, the can container 100 is a so-called bottle-type container for holding beverages, etc. For example, the can container 100 is made of a metal material such as aluminum alloy or surface-treated steel plate with resin films laminated on both sides. The can container 100 is formed into a cylindrical shape with a shortened diameter at one end and a different outer diameter. The can container 100 has an opening 110 at one end for discharging the contained beverage. The opening 110 has a jaw portion 111, an external thread portion 112, and a coiled portion 113 on its outer peripheral surface from the bottom surface side of the can container 100 toward the end.

[0037] The jaw portion 111 is formed by a ring-shaped protrusion. The curled portion 113 is formed with a smaller diameter than the external thread portion 112. In addition, the curled portion 113 is formed with a smaller inner diameter than the cap 1. The curled portion 113 is formed by bending the end of the opening portion 110 more than once. The curled portion 113 forms an opening for discharging the beverage contained in the can container 100.

[0038] like Figures 1 to 6 As shown, the cover 1 has a cover body 11 and a sealing component 12 separately disposed inside the cover body 11.

[0039] The cover body 11 is made of a material in which a resin film layer is formed on a metal raw material such as aluminum alloy. The cover body 11 is formed into a cup shape from the thin-walled flat material by various forming methods such as stretch forming, knurling forming, roll forming, and stamping forming.

[0040] like Figures 1 to 4 As shown, the cover body 11 has a circular plate-shaped top plate portion 21 and a cylindrical skirt portion 22 hanging down from the periphery of the top plate portion 21. The cover body 11 is integrally formed by the top plate portion 21 and the skirt portion 22 through an annular and curved corner portion 23.

[0041] The top plate 21 is configured as a circular plate. For example... Figure 1 as well as Figure 4As shown, the main surface of the top plate portion 21 is formed as a plane. Furthermore, the top plate portion 21 may also undergo at least one processing of embossing and patterning on a portion thereof.

[0042] The skirt portion 22 is configured such that one end is connected to the top plate portion 21 via a corner portion 23, and the other end is open. For example... Figures 1 to 4 As shown, the skirt portion 22 has multiple locking portions 31, multiple ventilation slots 32, internal thread portions 33, anti-theft ring portions 34, and an upper annular portion 35. In the skirt portion 22, for example, the upper annular portion 35, multiple locking portions 31, multiple ventilation slots 32, internal thread portions 33, and anti-theft ring portions 34 are formed sequentially from the end on the top plate portion 21 side to the end of the opening.

[0043] The cup-shaped molded part 11A, consisting of a top plate portion 21, multiple unformed locking portions 31, multiple ventilation slots 32, internal thread portions 33, and an anti-theft ring portion 34, and a corner portion 23, is formed by knurling and roll forming processes. This results in multiple locking portions 31, multiple ventilation slots 32, internal thread portions 33, and an anti-theft ring portion 34 being formed on the skirt portion 22. Furthermore, the internal thread portions 33 are formed when the cover 1 is installed on the can container 100.

[0044] Multiple locking portions 31 are recessed radially inward through the skirt 22, restricting the movement of the sealing member 12 and thus retaining the sealing member 12. The locking portions 31 are recesses that do not form a gap extending through the skirt 22. For example... Figure 5 As shown, the locking portion 31 has an upper inclined surface 31a that slopes downwards and radially inwards from the upper annular portion 35 toward the cover 1 in a longitudinal section, and a lower inclined surface 31b that slopes upwards and radially inwards from the skirt portion 22 below the locking portion 31 toward the cover 1 in a longitudinal section. The multiple locking portions 31 are locked onto the inner surfaces of the multiple upper inclined surfaces 31a by the sealing member 12, restricting and retaining the movement of the sealing member 12.

[0045] like Figure 6 As shown, the vent slit 32 has a recess 32a and a vent slit 32b formed as part of the recess 32a. The vent slit 32 protrudes from the inner circumferential surface of the skirt 22. The vent slit 32b is a cut for releasing gas from the container 100 when it is opened.

[0046] For example, in this embodiment, there are 13 locking portions 31 and 4 ventilation seams 32 in the circumferential direction of the skirt portion 22. Therefore, the plurality of ventilation seams 32 are set at equal or approximately equal intervals in the circumferential direction of the skirt portion 22, and the plurality of locking portions 31 and the plurality of ventilation seams 32 are set at equal or approximately equal intervals in the circumferential direction of the skirt portion 22. In addition, the plurality of locking portions 31 are set to be closer to the top plate portion 21 side (upper annular portion 35 side) in the axial direction of the skirt portion 22 than the plurality of ventilation seams 32.

[0047] The internal thread portion 33 is configured to engage with the external thread portion 112 of the can container 100. The internal thread portion 33 is formed together with the can container 100. That is, the internal thread portion 33 is not formed in the finished product of the cover 1 installed in front of the can container 100, but is formed when it is integrally assembled with the can container 100.

[0048] The tamper-evident ring 34 engages with the jaw 111 of the can 100 in the direction in which the lid 1 leaves the can 100 and in the axial direction of the lid 1. Furthermore, the tamper-evident ring 34 has a break portion 34a for breaking and detaching from the skirt 22 when the lid 1 is opened. That is, the tamper-evident ring 34 is constructed by leaving a gap at the end of the skirt 22 through the break portion 34a, and similarly to the internal thread portion 33, when integrally assembled with the can 100, it engages with the jaw 111 by being shaped to fit the jaw 111 of the can 100.

[0049] The upper annular portion 35 is formed in the area between the multiple locking portions 31 of the skirt portion 22 and the top plate portion 21. For example, the upper annular portion 35 is formed as part of the corner portion 23. The upper annular portion 35 has multiple small-diameter portions 35a and multiple large-diameter portions 35b in its circumferential direction. The inscribed circle diameter (inner diameter) of the multiple small-diameter portions 35a is relatively smaller than the inscribed circle diameter (inner diameter) of the multiple large-diameter portions 35b.

[0050] The small diameter portion 35a is axially adjacent to the locking portion 31 of the cover 1. The inner diameter of the inner circle of the plurality of small diameter portions 35a is set to be smaller than the outer diameter of the sealing member 12, and the inner diameter of the inner circle of the plurality of large diameter portions 35b is set to be larger than the outer diameter of the sealing member 12.

[0051] When forming multiple locking portions 31, the upper annular portion 35 forms multiple small-diameter portions 35a by pulling the portion adjacent to the upper part of each locking portion 31 of the upper annular portion 35 radially inward and recessing it. In addition, in the parts of the upper annular portion 35 where multiple small-diameter portions 35a are not formed, that is, between the multiple small-diameter portions 35a in the circumferential direction, multiple large-diameter portions 35b are formed respectively.

[0052] Furthermore, in this embodiment, multiple ventilation seams 32 are arranged at equal or approximately equal intervals in the circumferential direction of the skirt portion 22, and multiple locking portions 31 and multiple ventilation seams 32 are arranged at equal or approximately equal intervals in the circumferential direction of the skirt portion 22. As a result, the circumferential length of the large-diameter portion 35b corresponding to the portion of the skirt portion 22 where the two locking portions 31 are adjacent in the circumferential direction is shorter than the circumferential length of the large-diameter portion 35b corresponding to the portion of the skirt portion 22 where the two locking portions 31 are arranged therebetween is shorter.

[0053] like Figure 4As shown, the sealing member 12 is separately constructed from the cover body 11. The sealing member 12 is a circular plate having an inner circle diameter of multiple locking portions 31 provided on the skirt 22 of the cover body 11, and an outer diameter larger than the inner circle diameter of multiple small diameter portions 35a. The sealing member 12 is integrally provided on the cover body 11 by engaging with the upper inclined surface 31a of the locking portions 31 that protrude radially from the inner circumference of the skirt 22 in the axial direction.

[0054] like Figure 1 , Figures 4 to 6 As shown, the sealing component 12 includes a circular sliding layer 41 and a circular sealing layer 42 integrally laminated on the sliding layer 41. In the sealing component 12, the sliding layer 41 and the sealing layer 42 are formed of different synthetic resins. In the sealing component 12, the sealing layer 42 is integrally laminated on the sliding layer 41.

[0055] For example, such as Figure 1 As shown, the sealing member 12 has a flat plate portion 12a that is thicker than the central portion in the region abutting the opening 110 on the outer periphery side, and a curved portion portion 12b whose outer peripheral edge on the top plate portion 21 side is curved. In other words, the sealing member 12 is formed in the shape of a circular plate, and the ridge on the top plate portion 21 side is formed into a curved surface with a predetermined curvature. Alternatively, the sealing member 12 may also have a structure with the same thickness as, for example, the flat plate portion 12a.

[0056] The sliding layer 41 is made of a resin material that is relatively harder than the sealing layer 42. Furthermore, the sliding layer 41 is made of a resin material that has no adhesiveness or adhesion to the resin film layer of the cover body 11. That is, the sliding layer 41 does not adhere to the top plate portion 21, and slides on the top plate portion 21 while in contact with it.

[0057] Examples of resin materials used for the sliding layer 41 include olefin resins such as polypropylene resin and polyethylene resin, polyester resins such as polypropylene terephthalate, styrene resins, and acrylic resins. In this embodiment, the sliding layer 41 is, for example, made of polypropylene resin. Furthermore, pigments, lubricants, softeners, etc., can be appropriately added to the resin material used for the sliding layer 41. Additionally, in this example, the hardness of the sliding layer 41 is D10 to D70 according to the D hardness of a hardness tester based on JIS-K7215.

[0058] like Figure 1 , Figures 4 to 6As shown, the sliding layer 41 is positioned opposite the top plate portion 21 of the cover body 11 and is separate from the cover body 11. The sliding layer 41 is constructed using a resin material, allowing it to slide against the top plate portion 21 of the cover body 11. The sliding layer 41 is shaped like a circular plate. The outer diameter of the sliding layer 41 is smaller than the inner diameter of the skirt portion 22. The outer diameter of the sliding layer 41 is larger than the inner diameter of the inscribed circles of the plurality of locking portions 31 and the plurality of small-diameter portions 35a, and smaller than the inner diameter of the plurality of large-diameter portions 35b. The outer diameter of the sliding layer 41 is larger than the outer diameter of the curled portion 113 of the opening portion 110.

[0059] like Figure 5 as well as Figure 6 As shown, the sliding layer 41 includes, for example, a first flat plate portion 41a of uniform thickness and a first curved portion 41b whose outer peripheral surface on the top plate portion 21 side is formed by a curved surface. Additionally, the sliding layer 41 includes, for example, a protrusion 41c provided on the sealing layer 42 side of the first curved portion 41b. The first flat plate portion 41a is configured to have the same thickness from the center of the sliding layer 41 to the portion closer to the outer periphery than the portion opposite to the curled portion 113 of the opening portion 110.

[0060] The thickness of the portion of the first curved surface 41b facing the curled portion 113 of the opening 110 gradually decreases from the outer periphery to the outer periphery. The protrusion 41c is configured as a circular protrusion that is inclined relative to the axial direction of the sliding layer 41 and the surface direction of the top plate portion 21, and bends or tilts towards the end side of the opening of the skirt portion 22. In the protrusion 41c, the thickness gradually decreases from the first curved surface 41b towards the front end.

[0061] The sealing layer 42 is made of a (soft) resin material that is relatively less hard than the sliding layer 41. Examples of resin materials used for the sealing layer 42 include olefin-based resins, polyester-based resins, styrene-based resins, and acrylic resins; more preferably, examples include mixtures of styrene-based elastomers and polypropylene resins, mixtures of low-density polyethylene and styrene-based elastomers, and polyester elastomers. The resin material used for the sealing layer 42 and the resin material used for the sliding layer 41 have adhesive properties. In this embodiment, the sealing layer 42 is made of, for example, a mixture of styrene-based elastomers and polypropylene resins. Furthermore, pigments, lubricants, softeners, etc., may be appropriately added to the resin material used for the sealing layer 42.

[0062] like Figure 1 , Figures 4 to 6As shown, the sealing layer 42 is integrally formed on the main surface of the sliding layer 41 on the side opposite to the opening 110. The sealing layer 42 is configured as a circular plate. The outer diameter of the sealing layer 42 is smaller than the inner diameter of the skirt 22. The outer diameter of the sealing layer 42 is larger than the inner circle diameter of the plurality of locking portions 31 and the inner circle diameter of the plurality of small diameter portions 35a, and smaller than the inner circle diameter of the plurality of large diameter portions 35b. The outer diameter of the sealing layer 42 is configured to be larger than the outer diameter of the curled portion 113 of the opening 110. The outer diameter of the sealing layer 42 is set to, for example, the same diameter as the outer diameter of the sliding layer 41.

[0063] like Figure 5 as well as Figure 6 As shown, the sealing layer 42 includes a second flat plate portion 42a of the same thickness, a second curved portion 42b whose outer peripheral surface on the top plate portion 21 side is formed by a curved surface, and a thick-walled portion 42c provided in the second flat plate portion 42a. In the second flat plate portion 42a, the main surface opposite to the curled portion 113 is configured as a plane. For example, the second flat plate portion 42a is configured to have the same diameter as the first flat plate portion 41a of the sliding layer 41. The second flat plate portion 42a and the first flat plate portion 41a together constitute the flat plate portion 12a of the sealing member 12. Furthermore, in this embodiment, the first flat plate portion 41a and the second flat plate portion 42a are, for example, set to have the same thickness.

[0064] The second curved surface 42b, for example, has a main surface that is coplanar with the main surface opposite to the curled portion 113 of the second flat plate portion 42a. The second curved surface 42b is configured such that the thickness of the portion relative to the portion opposite to the curled portion 113 of the opening portion 110, towards the outer periphery, gradually decreases towards the outer periphery. The second curved surface 42b is stacked on the first curved surface 41b and the protrusion 41c. The second curved surface 42b, together with the first curved surface 41b and the protrusion 41c, constitutes the curved surface 12b of the sealing member 12.

[0065] The thick-walled portion 42c is an annular protrusion projecting from the main surface of the second flat plate portion 42a opposite to the sliding layer 41 side. The thick-walled portion 42c forms a sealing portion that abuts against the opening 110 of the container 100. Furthermore, the sliding layer 41 is configured to have a recess, i.e., a thin-walled portion, at the location opposite to the thick-walled portion 42c, and the thick-walled portion 42c protrudes annularly from both main surfaces of the second flat plate portion 42a, which can also be a structure to ensure the amount of deformation of the thick-walled portion 42c.

[0066] In the sliding layer 41 and the sealing layer 42, the first curved portion 41b, the protrusion 41c and the second curved portion 42b are respectively thinner than the first flat portion 41a and the second flat portion 42a.

[0067] Next, regarding the manufacturing method of the cover 1 with this configuration, Figure 8 as well as Figure 9 Please provide an explanation.

[0068] First, a sheet of metal material is extruded using a pressing device to form a molded part 11A (step ST1). Next, a sliding layer 41 is formed on the top plate portion 21 of the molded part 11A using a sliding layer forming device (step ST2).

[0069] Next, a sealing layer 42 is formed on the sliding layer 41 within the molded part 11A using a sealing layer forming device (step ST3). Thus, a sealing component 12 is formed within the molded part 11A.

[0070] Next, the sealing component 12 is removed from the molded part 11A by the sealing component conveying device (step ST4). Next, a plurality of locking parts 31, a plurality of ventilation slots 32, an anti-theft ring part 34, and an upper annular part 35 are formed on the molded part 11A from which the sealing component 12 has been removed by the molding component processing device (step ST5).

[0071] Next, the sealing component 12 is inserted into the molded part 11A, which has multiple locking parts 31, multiple ventilation slots 32, anti-theft ring parts 34, and upper annular parts 35, via the sealing component conveying device (step ST6). Through these processes, the cover 1 is manufactured (step ST7).

[0072] Furthermore, for example, the manufactured caps 1 are collected by the collection department. When a certain number of caps 1 are collected, they are conveyed to the next process, namely the inspection and packaging process, for quality inspection and packaging.

[0073] Next, the method of sealing the opening 110 of the manufactured lid 1 to the can container 100 will be described. For example, the lid 1 is placed on the opening 110 of the can container 100 such that the front end of the opening 110 of the can container 100, i.e., the curled portion 113, contacts the sealing layer 42 of the sealing member 12. In this state, a load is applied to the top plate portion 21 of the lid body 11, and the skirt portion 22 is rolled and formed while stretching the corner portion 23 downward (towards the can container 100). Thus, as Figure 1 As shown, an internal thread 33 is formed on the skirt 22 of the cap 1, and the cap 1 is tightened and fixed to the opening 110 of the container 100. Furthermore, this sealing method is performed while the container 100 is filled with beverage. Additionally, for example, the container 100 after being sealed with cap 1 may undergo distillation processing based on its contents.

[0074] Next, the forming part processing device adopts... Figures 10 to 16 An example of the structure of the manufacturing apparatus 200 for forming the multiple locking portions 31, multiple ventilation slots 32, and upper annular portion 35 of the cover 1 in step ST5 described above will be explained.

[0075] Furthermore, in Figures 11 to 13In order to illustrate the combination of the positions of the first tool 211 and the second tool 212, it will be explained in detail below. Figure 10 The positions a, b, and c of each tool 211 are specified as A, B, and C of positions 212, respectively. Therefore... Figure 11 , Figure 12 , Figure 13 The cross-sections of tools 211 and 212 at the aA combination, the bB combination, and the cC combination are shown respectively.

[0076] like Figures 10 to 16 As shown, the manufacturing apparatus 200 includes a first tool 211, a second tool 212, and a drive device 213. The manufacturing apparatus 200 is a device that forms multiple locking portions 31, multiple ventilation seams 32, anti-theft ring portions 34, multiple small-diameter portions 35a, and multiple large-diameter portions 35b on the skirt portion 22 of the cover body 11 (molded part 11A) by knurling. For example, the manufacturing apparatus 200 forms the portion of the skirt portion 22 located between the first tool 211 and the second tool 212 by rotating the first tool 211 and the second tool 212 relative to each other using the drive device 213.

[0077] like Figures 10 to 16 As shown, the first tool 211 includes a first base 221, a plurality of first protrusions 222, a plurality of cutting portions 223, a plurality of small-diameter portion forming portions 224, a plurality of large-diameter portion forming portions 225, a first anti-theft ring portion forming portion 226 provided on the first base 221, and a rotating shaft 227 provided on the first base 221.

[0078] In the first tool 211, the first base 221 and a plurality of first protrusions 222 are disposed within the cover body 11.

[0079] The first tool 211 is composed of multiple components.

[0080] The first base 221 is disposed within the skirt 22 of the cover body 11. The first base 221 is cylindrical with an outer diameter smaller than the inner diameter of the skirt 22. The first base 221 has, for example, a hole 221a for inserting a rotating shaft 227. The hole 221a has, for example, a keyway.

[0081] The first protrusion 222 may be, for example, a semi-cylindrical shape or a two-part curved triangular prism shape along the axial direction of the first base 221. The plurality of first protrusions 222 are spaced circumferentially from adjacent first protrusions 222. Thus, the predetermined interval is set to be a width greater than the circumferential width of the second protrusion 232 of the second tool 212, which will be described later.

[0082] The cutting portion 223 is a protrusion that, together with the second protrusion 232 of the second tool 212, cuts, breaks, or severs the portion of the skirt 22 where the ventilation slit 32b is formed. The cutting portion 223 is provided on one side of an adjacent first protrusion 222 among a plurality of first protrusions 222 and between the adjacent first protrusions 222.

[0083] The small-diameter forming portion 224 is a recess located axially adjacent to the end side of the first base 221, which is closer to the first protrusion 222. The large-diameter forming portion 225 is a protrusion formed circumferentially adjacent to the small-diameter forming portion 224. Furthermore, the large-diameter forming portion 225 is located in a region axially adjacent to the cutting portion 223. These plurality of small-diameter forming portions 224 and plurality of large-diameter forming portions 225 are circumferentially convex and concave shapes located at the end of the first base 221.

[0084] The first anti-theft ring forming part 226 forms the skirt part 22 according to the shape of the anti-theft ring part 34, while intermittently forming gaps to form multiple fracture parts 34a.

[0085] The rotating shaft 227 is fixed to the hole 221a of the first base 221. The rotating shaft 227 is connected to the drive device 213.

[0086] The second tool 212 is disposed on the outer peripheral surface of the skirt 22, and together with the first tool 211, forms multiple locking parts 31, multiple ventilation seams 32, anti-theft ring parts 34, multiple small-diameter parts 35a, and multiple large-diameter parts 35b on the skirt 22. For example... Figures 10 to 16 As shown, the second tool 212 includes a second base 231, a plurality of second protrusions 232, and a second anti-theft ring forming part 233 provided on the second base 231.

[0087] The second base 231 is, for example, in the shape of an arcuate plate. The outer diameter of the second base 231 is, for example, set to be larger than the outer diameter of the first base 221 and the outer diameter of the skirt 22. Furthermore, the second base 231 can be circular, quarter-circular, or semi-circular, as long as it has an outer peripheral surface with a curvature capable of appropriately forming multiple locking portions 31, multiple ventilation slots 32, multiple small-diameter portions 35a, and multiple large-diameter portions 35b together with the first tool 211. Additionally, the second base 231 can be rotatable, or it can be a non-rotatable structure if the first base 221 rotates.

[0088] In the second protrusion 232, for example, the front end is formed as a curved surface, and it is formed on a plane on one side of the axial direction (the top plate portion 21 side of the skirt portion 22). In addition, the second protrusion 232 is formed in a shape that gradually narrows in width in the axial direction and in the direction orthogonal to the axial direction as it moves toward the front end.

[0089] like Figure 10As shown, the second protrusion 232 may have, for example, a first tooth 232A forming a ventilation slot 32 and a second tooth 232B forming a locking portion 31. Thus, the first tooth 232A and the second tooth 232B can be appropriately formed to form the ventilation slot 32 and the locking portion 31 respectively, and different shapes can be formed. However, if the locking portion 31 and the ventilation slot 32 can be appropriately formed, they can also be the same shape.

[0090] The second anti-theft ring forming part 233, together with the first anti-theft ring forming part 226, forms the skirt part 22 according to the shape of the anti-theft ring part 34, while intermittently forming gaps and forming multiple fracture parts 34a.

[0091] Such a second protrusion 232 enters between adjacent first protrusions 222 through the end face of the front end, pressing the skirt portion 22 to form a recess. As a specific example of step ST5 of the above manufacturing method, with the first base 221 of the first tool 211 inserted into the molded part 11A, the first tool 211 and the second tool 212 are moved relative to each other. Then, as... Figures 11 to 13 As shown, the end face of each second protrusion 232 sequentially enters between adjacent first protrusions 222, thereby pressing the skirt portion 22. At this time, the end face of the second protrusion 232 is located radially outside the first tool 211, closer to the center side of the first base portion 221 than radially outside the small diameter forming portion 224.

[0092] For example, when the axially cut portion 223 is adjacent to the adjacent first protrusion 222, such as Figure 11 As shown, during the forming of the recess, the first tooth 232A of the cutting part 223 and the second protrusion 232 forms a ventilation slit 32b in a part of the recess, which constitutes the ventilation slit part 32.

[0093] Furthermore, in the case where the axially cut portion 223 is not adjacent to the end of the adjacent first protrusion 222, such as Figure 12 As shown, the recess formed by the second tooth 232B of the second protrusion 232 constitutes the locking part 31.

[0094] In addition, at this time, such as Figure 12 As shown, the second protrusion 232 causes the upper annular portion 35 on the top plate portion 21 side of the skirt portion 22 to move towards the recess, i.e., the small-diameter portion forming portion 224. As a result, the portion adjacent to the locking portion 31 of the skirt portion 22 on the top plate portion 21 side is plastically deformed by being pulled towards the small-diameter portion forming portion 224 and thus recessed, forming the small-diameter portion 35a. Furthermore, the portion adjacent to the small-diameter portion 35a in the circumferential direction is pressed against the large-diameter portion forming portion 225, forming the large-diameter portion 35b adjacent to the small-diameter portion 35a. Additionally, the portion of the upper annular portion 35 adjacent to the ventilation seam portion 32 forms the large-diameter portion 35b.

[0095] The drive unit 213 is a drive source that causes the first tool 211 and the second tool 212 to rotate relative to each other. The drive unit 213, for example, rotates the rotating shaft 227. The drive unit 213 is, for example, a transmission mechanism that transmits the rotation of an engine to the rotating shaft 227. The drive unit 213 causes the first tool 211 to rotate in one direction.

[0096] Furthermore, the drive device 213 can also rotate the first tool 211 and the second tool 212 relative to each other. It can be configured such that the second base 231 of the second tool 212 rotates without rotating the first base 221 via the rotation axis 227 of the first tool 211. Alternatively, it can rotate both the first base 221 and the second base 231. Additionally, the drive device 213 can be configured to move between an initial position where the first tool 211 is positioned on the cover body 11, and a forming position where the first tool 211 and the second tool 212 are in a predetermined positional relationship and the cover body 11 is formed.

[0097] In this configuration of the cover 1 and its manufacturing method, the inner diameter of the portion above the locking portion 31 on the skirt 22 (upper annular portion 35) between the multiple locking portions 31 and the top plate portion 21 is formed into a small diameter portion 35a, which is smaller than the inner diameter of the portion above the portion where the locking portion 31 is not formed. Therefore, the metal material located at the position where the small diameter portion 35a is formed before its formation is pulled radially inward during the forming of the locking portion 31. Thus, the locking portion 31 can be formed radially inward without damaging the skirt 22, and the inner circle diameter of the multiple locking portions 31 can be reduced. That is, the inner circle diameter of the multiple locking portions 31 can be made smaller than the outer diameter of the sealing member 12. Because the sealing member 12 can be supported by the multiple locking portions 31, the sealing member 12 can be reliably prevented from detaching from the cover body 11.

[0098] Furthermore, by setting the inner diameter of the inscribed circle of the plurality of small-diameter portions 35a to be smaller than the outer diameter of the sealing member 12, the inner circumferential surface of the small-diameter portion 35a abuts against the outer circumferential edge of the sealing member 12, thus holding the sealing member 12 in place. Therefore, in addition to being supported by the plurality of locking portions 31, the outer circumference of the sealing member 12 can be fixed by the small-diameter portions 35a, more reliably preventing the sealing member 12 from falling off the cover body 11. Moreover, the sealing member 12 disposed on the cover body 11 is radially aligned by the inner circumferential surfaces of the plurality of small-diameter portions 35a. Therefore, when the cover 1 is installed on the can container 100, the thick-walled portion 42c of the sealing member 12 reliably faces the opening 110 of the can container 100, thereby enabling the cover 1 to reliably seal the can container 100.

[0099] As described above, according to one embodiment of the present invention, the cover 1 and its manufacturing method can form a plurality of locking portions 31 supporting the sealing member 12 without damaging the skirt 22, and can form deep locking portions 31. Therefore, the cover 1 and its manufacturing method can reliably prevent the sealing member 12 from falling off the cover body 11.

[0100] Furthermore, the present invention is not limited to the embodiments described above. For example, in the above example, a plurality of locking portions 31 and a plurality of ventilation slots 32 are given, but the number of locking portions 31 and ventilation slots 32 can be appropriately set. That is, the number of locking portions 31 and ventilation slots 32 can be the same, and the number of locking portions 31 can be more or less than the number of ventilation slots 32. In addition, the shapes of locking portions 31 and ventilation slots 32 can also be appropriately set. Furthermore, the position and opening area of ​​the ventilation slot 32b of the ventilation slot 32 can also be appropriately set.

[0101] That is, as long as the sealing member 12 can be supported by multiple locking parts 31, the number and shape of locking parts 31 and ventilation slots 32 can be appropriately set according to the shape of the cover 1 and the can container 100, the contents contained in the can container 100, the internal pressure inside the can container 100, etc.

[0102] That is, the present invention is not limited to the above-described embodiments, and various modifications can be made during implementation without departing from its spirit. Furthermore, the embodiments can be appropriately combined to achieve combined effects. Moreover, the above embodiments include various inventions, and various inventions can be obtained through combinations selected from the disclosed multiple constituent elements. For example, if the technical problem can be solved and the desired effect achieved even if several constituent elements are deleted from all the constituent elements shown in the embodiments, the structure in which those constituent elements are deleted can also be obtained as an invention.

[0103] Explanation of reference numerals in the attached figures

[0104] 1: Cover; 11: Cover body; 11A: Molded part; 12: Sealing component; 12a: Flat plate part; 12b: Curved surface part; 21: Top plate part; 22: Skirt part; 23: Corner part; 31: Locking part; 31a: Upper inclined surface; 31b: Lower inclined surface; 32: Ventilation seam part; 32a: Recess; 32b: Ventilation seam; 33: Internal thread part; 34: Anti-theft ring part; 34a: Fracture part; 35: Upper annular part; 35a: Small diameter part; 35b: Large diameter part; 41: Sliding layer; 41a: First flat plate part; 41b: First curved surface part; 41c: Protrusion; 42: Sealing layer; 42a: Second flat plate part; 42b: : Second curved surface, 42c: Thick wall portion, 100: Can container, 110: Mouth, 111: Jaw portion, 112: External thread portion, 113: Coiled portion, 200: Manufacturing device, 211: First tool, 212: Second tool, 213: Drive device, 221: First base, 221a: Hole, 222: First protrusion, 223: Cutting portion, 224: Small diameter portion forming portion, 225: Large diameter portion forming portion, 226: First anti-theft ring portion forming portion, 227: Rotating shaft, 231: Second base, 232: Second protrusion, 232A: First tooth, 232B: Second tooth, 233: Second anti-theft ring portion forming portion.

Claims

1. A cover, wherein, have: The cover body has a top plate portion and a cylindrical skirt portion disposed on the periphery of the top plate portion; A sealing component, which is separate from the cover body and disposed inside the cover body opposite to the top plate portion; The locking portion has multiple portions in the circumferential direction of the skirt portion, protrudes inward in the radial direction of the skirt portion and supports the sealing component; Multiple small-diameter portions are disposed between the multiple locking portions and the top plate portion of the skirt portion, and are respectively disposed on the top plate portion side of the locking portion in the axial direction; The large-diameter portion has multiple sections adjacent to the small-diameter portions in the circumferential direction, and the inner circle diameter of the large-diameter portion is larger than the inner circle diameter of the multiple small-diameter portions. The small diameter portion is adjacent to the locking portion and the top plate portion.

2. The cover according to claim 1, wherein, The inscribed circle diameter of the plurality of smaller diameter portions is smaller than the outer diameter of the sealing component.

3. The cover according to claim 1 or 2, wherein, have: The skirt has multiple ventilation seams along its circumference.

4. A method for manufacturing a lid, wherein, A molded part is disposed on a first tool, the molded part having a top plate portion and a skirt portion integrally formed on the top plate portion via an annular and curved corner portion, the first tool having a plurality of first protrusions on its outer peripheral surface, and having a plurality of large-diameter molded portions axially adjacent to the first protrusions and small-diameter molded portions circumferentially adjacent to the large-diameter molded portions. A second tool having a second protrusion disposed between adjacent first protrusions of the first tool is rotated relative to the first tool, causing the second protrusion to enter between adjacent first protrusions, thereby forming a plurality of recesses, a plurality of small-diameter portions, and a plurality of large-diameter portions in the skirt.

5. The method for manufacturing a lid according to claim 4, wherein, After the recess and the small diameter portion are formed, the sealing component is inserted into the formed part.

6. The method for manufacturing a lid according to claim 5, wherein, The inscribed circle diameter of the plurality of smaller diameter portions is smaller than the outer diameter of the sealing component.

7. The method of manufacturing the cap according to any one of claims 4 to 6, wherein, The first tool has multiple cutting sections that form a ventilation slit in a portion of the recess.

Images