Cap unit, manufacturing method thereof, and capped container

Abstract

To provide a suitable cap unit in which a waterproof packing is integrally formed with a cap body. [Solution] The cap body closes the top opening of the container body when fitted inside the container body from the top opening of the container body. The cap body has an inner plug (10) that is fitted inside the container body from the top opening of the container body, and a watertight gasket (15) that is molded integrally with the outer periphery of the lower end side of the inner plug (10) and seals the space between the container body and the inner plug (10). The inner plug (10) has a boundary surface (12a) that faces the top surface of the watertight gasket, an inclined surface (12b) that inclines upward from outside the watertight gasket (15) on the boundary surface (12a), and an outer periphery surface (12c) that stands upward from outside the inclined surface (12b).

Description

[Technical Field]

[0001] The present invention relates to a cap unit, a method for manufacturing the same, and a capped container. [Background technology]

[0002] Conventionally, there have been capped containers equipped with a cap unit (stopper) that is removably attached to the mouth and neck of a container body that has an open top, thereby closing the top opening of the container body (see, for example, Patent Document 1 below).

[0003] Such a cap unit has a cap body that closes the top opening of the container body and is attached to the container body by screwing. The cap unit also has a waterproof gasket that is detachably attached to the cap body, and this waterproof gasket seals (watertightly seals) the gap between the container body and the cap body.

[0004] The waterproof gasket is made of a ring-shaped elastic member and is attached by fitting to the outer periphery of the lower end of the inside plug, which is fitted inside the container body of the cap body. When the cap body is screwed onto the container body, the waterproof gasket abuts against a protruding portion that protrudes from the inside of the container body all around, and elastically deforms to come into close contact with the protruding portion all around. This makes it possible to seal (watertightly seal) the gap between the container body and the cap body. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-187058 Summary of the Invention [Problem to be solved by the invention]

[0006] Among the cap units mentioned above, there are some in which the waterproof gasket is formed integrally with the inner plug of the cap body by insert molding. Specifically, a mold is used to form a cavity space corresponding to the shape of the waterproof gasket between the inner plug and the cap body, and the waterproof gasket material is sealed in this cavity to form the waterproof gasket integrally with the cap body.

[0007] In this case, using a mold that is divided in the axial direction of the cap body rather than using a mold that is divided in a direction perpendicular to the axial direction of the cap body makes it possible to increase the number of cap units (yield) produced in one molding run, due to the structure of the mold and the shape of the inner plug of the cap body that is inserted.

[0008] On the other hand, when a mold that is divided in the axial direction of the cap body is used, the inner plug of the cap body placed in the mold must be firmly pressed down by the mold in the axial direction to prevent flash. In this case, the inner plug of the cap body is generally made of a resin material, and the mold generally presses the inner plug from the opposite direction to prevent deformation of the inner plug due to the pressure and heat generated when the mold is closed. Furthermore, even if the inner plug is pressed down from the opposite direction, if the ends of the axially elongated portions are pressed together, the inner plug is susceptible to dimensional variations and is easily deformed by the pressure generated when the mold is closed.

[0009] For this reason, by making the outer diameter of the inner plug of the cap body larger than the outer diameter of the watertight gasket, a portion (pressing allowance) is secured on the outside of the watertight gasket, which is molded integrally with the inner plug, to press the inner plug in the axial direction (see, for example, Figure 3C of Patent Document 1 above).

[0010] However, when the majority of the overall height of the inner plug is fitted into the inside of the container body from the top opening of the container body, the outer diameter of the watertight gasket becomes smaller than the outer diameter of the inner plug of the cap body, and the inner diameter of the protruding part of the container body that abuts against the watertight gasket to stop water also becomes smaller. As a result, the difference between the inner diameter of the top opening of the container body and the inner diameter of the protruding part becomes large, and in order to ensure an appropriate inner diameter of the protruding part, the diameter of the top opening of the container body or the outer diameter of the container body must be large, which makes the container body itself larger.

[0011] The present invention has been proposed in consideration of the above-mentioned conventional circumstances, and aims to provide a suitable cap unit in which a waterproof gasket is formed integrally with the cap body, a method for manufacturing the same, and a capped container equipped with such a cap unit. [Means for solving the problem]

[0012] In order to achieve the above object, the present invention provides the following means. [1] A cap unit that can be detachably attached to a container body having an open top, a cap body that closes the upper opening of the container body when fitted into the container body from the upper opening, The cap body includes an inside plug that is fitted into the container body from an upper opening of the container body; a waterproof packing that is integrally formed on the outer periphery of the lower end of the inside plug and seals the gap between the container body and the inside plug; The cap unit is characterized in that the inner plug has a boundary surface facing the upper surface of the watertight gasket, an inclined surface that slopes upward from outside the watertight gasket on the boundary surface, and an outer peripheral surface that rises upward from outside the inclined surface. [2] The cap unit according to [1], wherein the inclined surface is linearly inclined in a cross section along the axial direction of the inside plug. [3] The cap unit according to [1], wherein the inclined surface is inclined in a curved shape in a cross section along the axial direction of the inside plug. [4] The cap unit described in [1], wherein the inner plug has a first recess shaped to correspond to a first convex portion protruding inward from the upper end of the inner periphery of the watertight gasket, and a second recess shaped to correspond to a second convex portion protruding upward from the lower end of the inner periphery of the watertight gasket. [5] The cap unit described in [4], characterized in that the inner plug has a third convex portion located between the first concave portion and the second concave portion and having a shape corresponding to a third concave portion formed between the first convex portion and the second convex portion of the water-stopping gasket. [6] A cap unit described in any one of [1] to [5], characterized in that the outer end of the boundary surface is located outside the outer upper end of the waterproof gasket. [7] The cap unit according to any one of [1] to [6], wherein the bottom surface of the inside plug is flush with the bottom surface of the watertight gasket. [8] A method for manufacturing the cap unit according to any one of [1] to [7], When the watertight gasket is integrally formed with the cap body using a mold that forms a cavity space corresponding to the shape of the watertight gasket between the inside plug and the mold, A method for manufacturing a cap unit, comprising forming the cavity space between the mold and the inside plug while the mold is in contact with the inclined surface. [9] A method for manufacturing the cap unit according to [8], characterized in that a mold that is divided in the axial direction of the cap body is used.

[10] A method for manufacturing a cap unit according to [8] or [9], characterized in that the waterproof packing is molded from liquid silicone.

[11] The cap unit according to any one of [1] to [7] above; A capped container comprising: a container body to which the cap unit is attached.

[12] The capped container according to

[11] , wherein the container body has a vacuum insulation structure. [Effects of the Invention]

[0013] As described above, according to the present invention, it is possible to provide a suitable cap unit in which a waterproof gasket is formed integrally with the cap body, a manufacturing method thereof, and a capped container equipped with such a cap unit. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view showing the appearance of a capped container equipped with a cap unit according to one embodiment of the present invention; [Figure 2] 2 is a cross-sectional view showing the configuration of a capped container equipped with the cap unit shown in FIG. 1. FIG. [Figure 3] 2 is a cross-sectional perspective view showing the configuration of the cap unit shown in FIG. 1. FIG. [Figure 4] 2 is a bottom view showing the configuration of the cap unit shown in FIG. 1. FIG. [Figure 5] 2A and 2B are perspective views of the outer lid of the cap unit shown in Fig. 1, as seen from above and below, respectively. [Figure 6] 2A is a perspective view of the inside plug included in the cap unit shown in Fig. 1, as seen from above, and FIG. 2B is a perspective view of the inside plug included in the cap unit shown in Fig. 1, as seen from below. [Figure 7] 2 is a cross-sectional view showing a state before an inside plug is attached to the outer lid of the cap unit shown in FIG. 1. FIG. [Figure 8] 2 is a cross-sectional view illustrating a state in which an inside plug is attached to an outer lid of the cap unit shown in FIG. 1. FIG. [Figure 9] 2 is a cross-sectional view illustrating a state in which an inside plug is attached to an outer lid of the cap unit shown in FIG. 1. FIG. [Figure 10] 2 is an enlarged cross-sectional view of the main parts of an inside plug and a waterproof gasket provided in the cap unit shown in FIG. 1. [Figure 11] 10 is a cross-sectional view illustrating a state in which a watertight gasket is integrally formed with an inside plug using a mold. FIG. [Figure 12] FIG. 12 is an enlarged cross-sectional view of a main part shown in FIG. [Figure 13] 11 is a cross-sectional view showing another shape of the inclined surface shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. (Cap unit and container with cap) First, as one embodiment of the present invention, a capped container 100 including a cap unit 1 shown in, for example, FIGS. 1 to 10 will be described.

[0016] FIG. 1 is a perspective view showing the appearance of a capped container 100 including a cap unit 1. FIG. 2 is a cross-sectional view showing the configuration of a capped container 100 including a cap unit 1. FIG. 3 is a cross-sectional perspective view showing the configuration of the cap unit 1. FIG. 4 is a bottom view showing the configuration of the cap unit 1. FIG. 5(A) is a perspective view of the outer lid 9 included in the cap unit 1 shown in FIG. 1, seen from above. FIG. 5(B) is a perspective view of the outer lid 9 included in the cap unit 1 shown in FIG. 1, seen from below. FIG. 6(A) is a perspective view of the inside plug 10 included in the cap unit 1 shown in FIG. 1, seen from above. FIG. 6(B) is a perspective view of the inside plug 10 included in the cap unit 1 shown in FIG. 1, seen from below. FIG. 7 is a cross-sectional view showing a state before the inside plug 10 is attached to the outer lid 9 of the cap unit 1. FIG. 8 is a cross-sectional view illustrating the state of attaching the inside plug 10 to the outer lid 9 of the cap unit 1. FIG. 9 is a cross-sectional view illustrating the state of attaching the inside plug 10 to the outer lid 9 of the cap unit 1. FIG. 10 is an enlarged cross-sectional view of the main parts of the inside plug 10 and the waterproof gasket 15 provided in the cap unit 1. As shown in FIG.

[0017] As shown in Figures 1 and 2, the capped container 100 of this embodiment is a beverage container that comprises a container body 2 with an open top and a cap unit 1 that can be attached and detached to the container body 2, and is capable of keeping the beverage (contents) contained in the container body 2 hot or cold.

[0018] Specifically, the container body 2 has an outer container 3 and an inner container 4 made of metal, such as stainless steel. The container body 2 has a vacuum insulation structure in which the outer container 3 and the inner container 4, each having an open end, are joined together near their open ends in a state in which the inner container 4, also having an open end, is housed inside the outer container 3, which also has an open end, and a vacuum insulation layer 5 is provided between the outer container 3 and the inner container 4.

[0019] The vacuum insulation layer 5 can be formed, for example, by sealing an air vent hole provided in the center of the bottom surface of the outer container 3 with brazing material in a chamber that has been depressurized (evacuated) to a high vacuum.

[0020] The container body 2 has such a vacuum insulation structure, which allows it to have the above-mentioned functions of keeping things warm or cold. Furthermore, the container body 2 has such a vacuum insulation structure, which causes tension to be constantly applied to the outer container 3 and the inner container 4 due to the difference between the internal pressure (vacuum pressure) and the external pressure (atmospheric pressure), thereby increasing the mechanical strength of the outer container 3 and the inner container 4. This makes it possible to increase the rigidity of the container body 2 even when the plate thicknesses of the outer container 3 and the inner container 4 are reduced, and thus makes it possible to reduce the weight of the container body 2.

[0021] The container body 2 has a substantially circular bottom surface 2b, a body 2c that stands in a substantially cylindrical shape from the outer periphery of the bottom surface 2b, and a mouth / neck portion 2d that stands in a substantially cylindrical shape from the upper side of the body 2c. The upper end of the mouth / neck portion 2d opens in a circular shape as the upper opening 2a of the container body 2.

[0022] The inner circumferential surface of the mouth / neck portion 2d is provided with a female thread portion 6. Furthermore, below the female thread portion 6, a ring-shaped protruding portion 7 is provided so as to protrude from the inner circumferential surface of the inner container 4 around the entire circumference.

[0023] Although the capped container 100 of this embodiment has an overall substantially cylindrical external shape, the external shape of the capped container 100 is not particularly limited and can be modified as appropriate to suit the size, design, etc. The outer peripheral surface of the container body 2 (outer container 3) may be painted, printed, or the like.

[0024] The cap unit 1 of this embodiment constitutes a lid that opens and closes the upper opening 2a of the container body 2. Specifically, as shown in Figures 3 and 4, this cap unit 1 has a cap body 8 that closes the upper opening 2a of the container body 2 when fitted into the inside of the container body 2 from the upper opening 2a of the container body 2, and has a structure in which this cap body 8 is attached to the container body 2 by screwing.

[0025] The cap body 8 has an outer lid 9 that covers the upper opening 2a of the container body 2, an inner stopper 10 that is fitted into the inside of the container body 2 from the upper opening 2a, and a detachment mechanism 11 that attaches the inner stopper 10 to the outer lid 9 in a freely detachable manner.

[0026] As shown in Figures 2 and 5(A) and (B), the outer lid 9 is made of, for example, a heat-resistant resin, and has a peripheral wall portion 9a that is formed in an approximately cylindrical shape so that its appearance is continuous with the trunk portion 2c of the container body 2, and an upper wall portion 9b that closes the upper part of the peripheral wall portion 9a.

[0027] As shown in Figures 2 and 6(A) and (B), the inside plug 10 is made of, for example, a heat-resistant resin, and has a substantially circular bottom wall portion 10a, a peripheral wall portion 10b that rises from the periphery of the bottom wall portion 10a in a substantially cylindrical shape, a top wall portion 10c that closes the upper part of the peripheral wall portion 10b, and a flange portion 10d where the top wall portion 10c protrudes in the radially expanding direction beyond the peripheral wall portion 10b.

[0028] The inside plug 10 has a substantially cylindrical lower plug member 12 with a bottom that forms the bottom wall portion 10a and the peripheral wall portion 10b, and a substantially circular upper plug member 13 that forms the top wall portion 10c and the flange portion 10d, and the lower plug member 12 is attached integrally to the underside of the upper plug member 13 by welding or the like. Note that the inside of the inside plug 10 is not limited to air as an insulating layer, and a thermal insulating material S may also be arranged.

[0029] Additionally, a male thread portion 14 is provided on the outer peripheral surface of the peripheral wall portion 10b (inner plug 10). In the capped container 100, the cap body 8 (cap unit 1) is detachably attached to the container body 2 by threading the male thread portion 14 into the female thread portion 6. Furthermore, the female thread portion 6 and the male thread portion 14 are double-threaded threads that are complementary to each other. When a double-threaded thread is used, the cap body 8 (cap unit 1) can be attached and detached to the container body 2 with a small rotational operation (approximately 180° in this embodiment).

[0030] A waterproof gasket 15 is attached integrally to the outer periphery of the lower end of the inside plug 10. The waterproof gasket 15 is a ring-shaped sealing member that seals the gap between the protruding portion 7 of the container body 2 and the inside plug 10, and is made of an elastic material such as a heat-resistant rubber such as silicone rubber or an elastomer. The waterproof gasket 15 is formed integrally with the inside plug 10 (cap body 8) by insert molding, which will be described later.

[0031] The inside plug 10 has a first recess 10e shaped to correspond to the first protrusion 15a that protrudes inward from the upper end of the inner periphery of the water stop gasket 15, and a second recess 10f shaped to correspond to the second protrusion 15b that protrudes upward from the lower end of the inner periphery of the water stop gasket 15. The inside plug 10 also has a third protrusion 10g shaped to correspond to the third recess 15c of the water stop gasket 15 that is formed between the first recess 10e and the second recess 10f of the inside plug 10 and is located between the first protrusion 15a and the second protrusion 15b of the water stop gasket 15.

[0032] In the cap unit 1 of this embodiment, the first convex portion 15a protruding inward of the watertight gasket 15 is formed integrally with the first concave portion 10e of the inside plug 10, and the second convex portion 15b protruding upward of the watertight gasket 15 is formed integrally with the second concave portion 10f of the inside plug 10. Furthermore, by integrally molding the third concave portion 15c of the watertight gasket 15 and the third convex portion 10g of the inside plug 10, the respective anchor effects can increase the adhesive strength of the watertight gasket 15 attached integrally to the inside plug 10 (cap body 8).

[0033] Furthermore, although the underside of the inside plug 10 has a shape in which the bottom wall portion 10a is recessed upward, it is flush with the underside of the water stop gasket 15. This makes it difficult for the water stop gasket 15 to peel off from the inside plug 10 at the boundary between the underside of the inside plug 10 and the underside of the water stop gasket 15. Furthermore, because there are no gaps near the boundary, water droplets do not easily accumulate, making it hygienic.

[0034] Additionally, two elastic flange portions 15d are provided on the outer peripheral surface of the watertight gasket 15, protruding in the radially expanding direction. When the cap body 8 (cap unit 1) is attached to the container body 2, the elastic flange portions 15d of the watertight gasket 15 elastically deform and come into close contact with the protruding portion 7 of the container body 2 over the entire circumference. This makes it possible to seal (watertightly seal) the gap between the protruding portion 7 (container body 2) and the inside plug 10 (cap body 8).

[0035] It should be noted that the waterproof gasket 15 is not necessarily limited to the shape described above, and for example, the number of elastic flange portions 15d is not limited to the two described above, but can be one or more.

[0036] Furthermore, the waterproof gasket 15 is not necessarily limited to the configuration provided with the elastic flange portion 15d described above, and its shape, etc., can be appropriately modified. For example, the waterproof gasket 15 may be configured to have an elastic flange portion that protrudes downward while curving from the upper end of the outer circumferential surface thereof.

[0037] As shown in Figures 2 to 9, the detachment mechanism 11 has a structure in which the inner plug 10 is attached to the outer lid 9 by abutting the upper surface of the inner plug 10 at a position offset from the center of the inner underside of the outer lid 9 and then sliding the inner plug 10 toward the center of the inner underside of the outer lid 9 (attachment direction).

[0038] Specifically, this detachment mechanism 11 includes a guide engagement portion 18 having an engagement hole 16 provided in the outer lid 9 and an engagement piece 17 provided in the inner plug 10, with the engagement piece 17 engaging with the engagement hole 16; a click locking portion 22 having an elastic piece 21 including a first click locking portion 19 provided in the outer lid 9 and a second click locking portion 20 provided in the inner plug 10, with either one of the first click locking portion 19 and the second click locking portion 20 (in this embodiment, the second click locking portion 20) locking the other locking portion (in this embodiment, the first click locking portion 19); and a slide locking portion 24 having a first slide locking portion 23 provided in the outer lid 9, with the flange portion (second slide locking portion) 10d of the inner plug 10 locking to the first slide locking portion 23.

[0039] The engagement hole 16 is formed by a hole that opens in the peripheral wall 9a located on one radial end side of the outer lid 9 and has a shape corresponding to the engagement piece 17. On the other hand, the engagement piece 17 is formed by a protrusion that protrudes outward from the flange 10d located on one radial end side of the inside plug 10.

[0040] With the engagement piece 17 inserted into the engagement hole 16, the guide engagement portion 18 can guide the inner plug 10 to slide freely radially relative to the outer lid 9, and when the inner plug 10 is slid to the center of the inner underside of the outer lid 9, the engagement piece 17 can be engaged with the engagement hole 16.

[0041] The first click locking portion 19 is located on the other radial end side of the outer lid 9 and is composed of a convex portion that protrudes downward from the upper wall portion 9b. On the other hand, the elastic piece 21 is provided extending in the radial direction from between a pair of slits 25 that cut out the flange portion 10d located on the other radial end side of the inside plug 10. The second click locking portion 20 is composed of a recessed portion in which a part of the elastic piece 21 is recessed downward in a shape corresponding to the first click locking portion 19.

[0042] The click locking portion 22 allows the first click locking portion 19 to be locked against the second click locking portion 20 of the elastically deformable elastic piece 21 when the inner plug 10 is slid to the center of the underside of the inner side of the outer lid 9.

[0043] In addition, the click locking portion 22 serves as a click mechanism that provides a clicking sensation when the inner plug 10 is slid to the center of the inner underside of the outer lid 9, and is capable of providing a clicking sensation when the first click locking portion 19 is locked with the second click locking portion 20 while elastically deforming the above-mentioned elastic piece 21.

[0044] The first slide locking portion 23 is located on the other radial end side of the outer lid 9 and is composed of a pair of rib walls that protrude inward from the peripheral wall portions 9a on both sides of the elastic piece 21, approximately parallel to the upper wall portion 9b.

[0045] As shown in Figure 4, when the inner plug 10 is slid to the center of the inner underside of the outer lid 9, the slide locking portion 24 allows the flange portion (second slide locking portion) 10d to be locked onto the first slide locking portion 23.

[0046] In the detachment mechanism 11 having the above configuration, the inside plug 10 is inserted into the inside of the outer lid 9 from the state shown in Fig. 7. At this time, as shown in Fig. 8, the engagement piece 17 is inserted into the engagement hole 16, and then the upper surface of the inside plug 10 is brought into contact with a position offset from the center of the bottom surface of the inside of the outer lid 9, as shown in Fig. 9. From this state, the inside plug 10 is slid toward the center of the bottom surface of the inside of the outer lid 9 (in the installation direction).

[0047] At this time, as shown in FIGS. 1 to 4, the engagement piece 17 engaged with the engagement hole 16 is substantially flush with the side surface of the outer lid 9. Furthermore, the first click engagement portion 19 is engaged with the second click engagement portion 20, thereby preventing the inside plug 10 from sliding radially (outward) relative to the outer lid 9. Furthermore, the engagement piece 17 of the inside plug 10 is engaged with the engagement hole 16 located at one radial end of the outer lid 9, and the flange portion (second slide engagement portion) 10d of the inside plug 10 is engaged with the first slide engagement portion 23 located at the other radial end of the outer lid 9, thereby preventing the inside plug 10 from falling off the outer lid 9 and also preventing the inside plug 10 from misaligning in the rotational direction relative to the outer lid 9. This results in the inside plug 10 being attached to the center of the lower surface inside the outer lid 9.

[0048] Furthermore, when the inner plug 10 is attached to the center of the inner underside of the outer lid 9, the inner abutment portion 9c on the inner side of the outer lid 9 shown in Figure 5(A) abuts against the straight portion 10h provided on the flange portion 10d shown in Figure 6(A), thereby preventing rattling and misalignment.

[0049] As shown in FIG. 6(A), the top wall 10c of the inside cap 10 is provided with upper surface protrusions 10i. The upper surface protrusions 10i are provided at equal intervals, rotating 90° in a plan view, so as to protrude upward. The upper surface protrusions 10i prevent deviations in the gap distance between the inside cap 10 and the central portion of the lower surface of the outer lid 9 due to dimensional errors of the inside cap 10 during or after the inside cap 10 is attached to the central portion of the lower surface of the outer lid 9. In other words, by fine-tuning the dimensions of the upper surface protrusions 10i, dimensional errors of the inside cap 10 can be absorbed, enabling the inside cap 10 to be stably attached to the central portion of the lower surface of the inner cap 9.

[0050] Meanwhile, in the detachment mechanism 11, the inside plug 10 is slid relative to the outer lid 9 in the opposite direction (removal direction) to the above-described direction, thereby releasing the locked state of the first click locking portion 19 relative to the second click locking portion 20 and releasing the locked state of the flange portion (second slide locking portion) 10d relative to the first slide locking portion 23. Next, the engagement of the engagement piece 17 relative to the engagement hole 16 is released. This allows the inside plug 10 to be removed from the outer lid 9.

[0051] In the cap unit 1 of this embodiment, the inner stopper 10 is detachably attached to the outer lid 9, so that the outer lid 9 and the inner stopper 10 can be washed separately, and the space between the outer lid 9 and the inner stopper 10 can be kept hygienic.

[0052] In the cap unit 1 of this embodiment, the lower plug member 12 (inner plug 10) has, as shown in Figure 10, a boundary surface 12a facing the upper surface of the watertight gasket 15, an inclined surface 12b inclined upward from outside the watertight gasket 15 of the boundary surface 12a, and an outer peripheral surface 12c standing upward from outside the inclined surface 12b.

[0053] The inclined surface 12b forms a linearly inclined surface (C-surface) in a cross section along the axial direction of the lower plug member 12 (inner plug 10). The inclined surface 12b is preferably inclined at an angle θ of 30° to 60° (45°±15°) with respect to the axial direction of the lower plug member 12 (inner plug 10).

[0054] The outer edge of boundary surface 12a may coincide with the outer upper edge, which is the upper edge of the adhesive surface of integrated waterproof gasket 15, or may be positioned slightly outward (protruding) from the outer upper edge of waterproof gasket 15. In this case, the distance D by which boundary surface 12a protrudes outward from waterproof gasket 15 is preferably 2.0 mm or less.

[0055] The smaller the distance D, the more aesthetically pleasing the appearance becomes, since the inclined surface 12b and the outer upper end of the watertight gasket 15 appear to be one continuous, integrated shape. Also, if the outer upper end of the watertight gasket 15 is located further outward than the outer end of the boundary surface 12a, this is not preferable because it may cause peeling of the upper end of the watertight gasket 15 depending on the area where the primer is applied, as described below.

[0056] (Cap unit manufacturing method) Next, a method for manufacturing the cap unit 1 will be described with reference to FIGS. 11 is a cross-sectional view illustrating the state in which watertight gasket 15 is integrally formed with inside plug 10 using mold 200. FIG. 12 is an enlarged cross-sectional view of the main part shown in FIG.

[0057] 11, the inside plug 10 (lower plug member 12) is upside down compared to the other figures. Therefore, the upward direction in Figures 1 to 10, 12, and 13 is the downward direction in Figure 11, and the downward direction in Figures 1 to 10, 12, and 13 is the upward direction in Figure 11.

[0058] In the manufacturing method of the above-mentioned cap unit 1, the watertight gasket 15 is formed integrally with the lower plug member 12 (inner plug 10) by insert molding using a mold 200 that forms a cavity space K shaped to correspond to the watertight gasket 15 between the lower plug member 12 (inner plug 10).

[0059] Furthermore, in the insert molding, a mold 200 that is divided in the axial direction of the lower plug member 12 (inner plug 10) is used. In this embodiment, the mold 200 that is divided into three molds 201, 202, and 203 is used.

[0060] Of these, the lower mold 201 in Figure 12 forms a cavity space K with the lower plug member 12 in a shape corresponding to the watertight gasket 15. Meanwhile, the upper mold 202 in Figure 12 is butted against the mold 201 on the outside of the lower plug member 12. A gap G is provided in the mold 202 to separate it from the male thread portion 14. Meanwhile, the upper mold 203 in Figure 12, which is located inside the mold 202, is brought into contact with the step portion 12d provided on the inside of the lower plug member 12 and an inner circumferential surface 12e rising upward from the outside of the step portion 12d on the inside of the lower plug member 12.

[0061] In the manufacturing method of the cap unit 1 of this embodiment, first, a plasma discharge treatment is performed on the surface of the molded lower plug member 12, and a surface modification treatment is performed to generate polar functional groups on the surface of the resin. Note that the process of generating polar functional groups is not limited to plasma discharge treatment, and surface modification treatments such as flame treatment, corona discharge treatment, and itro treatment can also be selectively used.

[0062] Next, a primer is applied to the surface of the surface-modified lower plug member 12, and this lower plug member 12 is placed in a mold 200. The primer is applied to the boundary surface 12a of the lower plug member 12, and portions that will become the boundary surface with the watertight gasket 15, such as the first recess 10e, the second recess 10f, and the third protrusion 10g.

[0063] The composition of the primer is not particularly limited as long as it chemically bonds with the surface of the heat-resistant resin material that forms the lower plug member 12 (inner plug 10) that has been surface-modified in a previous process, and also chemically bonds with the elastic material such as heat-resistant silicone rubber that forms the water-stopping gasket 15, thereby improving adhesion.

[0064] The method for applying the primer can also be selected appropriately. For example, if the viscosity of the primer is low, it may be applied by spraying or the like. If the viscosity is high, it may be applied by brush or the like. Alternatively, application by a dispenser or a dipping method may also be used.

[0065] Next, by closing the mold, a cavity space K is formed between the mold 201 and the lower plug member 12, with the mold 201 abutting against the inclined surface 12b of the lower plug member 12 placed in the mold 200. The upward arrow shown in Fig. 12 indicates the closing direction of the mold 201.

[0066] At this time, as shown in Figure 12, a force F is applied to the inclined surface 12b that is in contact with the mold 201 in a direction perpendicular to this inclined surface 12b, so that the axial force applied from the mold 201 to the lower plug member 12 is dispersed, and the mold 201 and the inclined surface 12b come into contact with each other with an appropriate contact pressure, thereby preventing deformation of the lower plug member 12.

[0067] Then, by insert molding, molten resin (e.g., liquid silicone) that will become the watertight gasket 15 is injected into the cavity space K, held therein, and molded, so that the watertight gasket 15 can be formed integrally with the inner plug 10 (cap body 8).

[0068] Generally, when molding liquid silicone rubber, the resin has high fluidity during filling, so even the slightest gap when the mold is closed will result in the formation of burrs. For this reason, it is necessary to manufacture the mold with high precision.

[0069] Furthermore, in insert molding, it is necessary to minimize gaps while pressing the insert (lower plug member 12 in this embodiment) to prevent deformation. When the insert is made of a resin material, as in this embodiment, even if it is a heat-resistant resin, pressing it too hard into the mold may cause deformation due to the heat of molding and the pressure of closing the mold.

[0070] In contrast, in this embodiment, as described above, the inclined surface 12b is inclined at an angle θ, so that the mold 201 and the inclined surface 12b abut at an angle of 45° relative to the axial direction of the closing of the mold, thereby abutting with an appropriate pressure and preventing gaps from occurring.

[0071] Furthermore, since the distance between the inclined surface 12b and the step portion 12d and inner surface 12e that abut against the mold 203 is short, even if there is a dimensional error in the lower plug member 12, it is possible to keep the amount of deformation of the lower plug member 12 caused by closing the mold small.

[0072] Therefore, in the manufacturing method of the cap unit 1 of this embodiment, deformation of the above-mentioned lower plug member 12 is minimized, and the lower plug member 12 placed in the mold 200 can be firmly pressed down in the axial direction by the mold 200, while being molded integrally with the water-stopping gasket 15.

[0073] In the integral molding of ordinary solid or semi-solid silicone rubber with low fluidity and a resin insert, the shape of the cavity space K must avoid a so-called undercut shape, particularly a deep undercut shape, which becomes convex or concave in a direction perpendicular to the opening and closing direction of the mold (the axial direction in this embodiment).

[0074] This is because, if solid or semi-solid silicone rubber is filled into the cavity K, the silicone rubber will not reach the deepest part of the undercut, which is likely to result in molding defects. Therefore, by shaping the cavity K so that it is coaxial with the opening and closing direction of the mold and has a slope similar to that of the draft taper, it is possible to make it easier to fill the silicone rubber.

[0075] In contrast, in the manufacturing method of the cap unit 1 of this embodiment, liquid silicone rubber is used to integrally mold the waterproof gasket 15 by injection molding. Liquid silicone rubber has high fluidity and can easily fill any shape. Therefore, even if the undercut shape is deep, the silicone rubber can reach the deepest part of the undercut and mold it, so the shape of the cavity space K in insert molding is not an issue.

[0076] In this embodiment, the first recess 10e of the lower plug member 12 (inner plug 10) has an undercut shape that is deep inward in the opening and closing direction of the mold 200. This, together with the second recess 10f that opens in the opening and closing direction of the mold 200, increases the contact area in the undercut direction between the lower plug member 12 (inner plug 10) and the watertight gasket 15, thereby making it possible to increase the adhesion strength.

[0077] The two elastic flange portions 15d provided on the outer peripheral surface of the waterproof gasket 15 also have an undercut shape that faces outward in the opening and closing direction (axial direction) of the mold 203. However, because the waterproof gasket 15 is molded from silicone rubber, after molding is complete, the elastic flange portions 15d are removed from the mold 203 while elastically deforming. This allows for so-called forced removal, which means that there are fewer restrictions on the shape of the cavity space K and it is possible to increase the degree of freedom in the shape of the cavity space K.

[0078] Furthermore, in the manufacturing method of the cap unit 1 of this embodiment, there is no need to secure a portion (pressure allowance) on the outside of the above-mentioned watertight gasket 15 to press the lower plug member 12 in the axial direction, so it is possible to prevent the outer diameter of the watertight gasket 15 from becoming smaller than the outer diameter of the middle plug 10.

[0079] Furthermore, since a mold that is divided in the axial direction of the cap body 8 is used rather than a mold that is divided in a direction perpendicular to the axial direction of the cap body 8, the number of cap units 1 produced in one molding (yield) can be increased due to the structure of the mold and the shape of the inner plug 10 of the cap body 8 that is inserted, making it possible to produce large quantities in a short period of time.

[0080] The present invention is not necessarily limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the inclined surface 12b shown in Fig. 10 forms a linearly inclined surface (C surface) in a cross section taken along the axial direction of the inside plug 10, but is not limited to this shape, and may form a convexly curved inclined surface (R surface) in a cross section taken along the axial direction of the inside plug 10, as in the case of the inclined surface 12f shown in Fig. 13. Fig. 13 is a cross-sectional view showing another shape of the inclined surface 12b shown in Fig. 10.

[0081] In this case, too, a force is applied to the inclined surface 12f in a direction perpendicular to the tangent of this inclined surface 12f when it comes into contact with the mold 201, which makes it possible to prevent deformation of the lower plug member 12 while dispersing the axial force applied from the mold 201 to the lower plug member 12. Although the inclined surface 12f has a convex curved shape, a similar effect can be obtained even if it has a concave curved shape instead.

[0082] For example, the cap unit 1 is configured such that the inner stopper 10 is attached to the container body 2 by screwing while being fitted into the inside from the upper opening 2a of the container body 2, but the configuration is not necessarily limited to this. For example, the cap unit 1 can also be configured such that the outer lid 9 is attached to the container body 2 by screwing while covering the upper opening 2a of the container body 2 from the outside.

[0083] In this configuration, instead of the above-mentioned female screw portion 6 and male screw portion 14, the outer lid 9 (cap body 8) can be removably attached to the container body 2 by screwing together a male screw portion provided on the outer peripheral surface of the neck portion 2d and a female screw portion provided on the inner peripheral surface of the peripheral wall portion 9a that constitutes the outer lid 9.

[0084] Furthermore, the capped container 100 is configured to directly open and close the upper opening 2a of the container body 2, but is not necessarily limited to this configuration. For example, it is also possible to configure the cap unit 1 to be detachably attached to a shoulder member attached to the container body 2.

[0085] Furthermore, it is also possible to configure the lid so that it can be opened and closed freely on the cap body that is attached to the container body 2. In this configuration, the lid may be attached to the cap body by screwing, or the lid may be attached to the cap body via a hinge so that it can be rotated freely.

[0086] In the above embodiment, the present invention is exemplified as being applied to a beverage container having a heat-retaining (or cold-retaining) function provided by a container body 2 having the above-mentioned vacuum insulation structure, but the present invention can be widely applied to a lidded container having a container body and a lid that can be attached and detached to the container body. [Explanation of symbols]

[0087] REFERENCE SIGNS LIST 1...cap unit 2...container body 3...outer container 4...inner container 5...vacuum insulation layer 6...female thread portion 7...projection portion 8...cap body 9...outer lid 10...inner plug 10d...flange portion (second slide locking portion) 10e...first recess 10f...second recess 10g...third protrusion 10h...straight portion 10i...upper surface protrusion 10j...flange portion 11...detachment mechanism 12...lower plug member 12a...boundary surface 12b...inclined surface 12c...outer peripheral surface 12f...inclined surface 13...upper plug member 14...male thread portion 15...waterstop packing 15a...first protrusion 15b...second protrusion 15c...third recess 16...engagement hole 17...engagement piece 18...guide engagement portion 19...first click locking portion 20... Second click locking portion 21... Elastic piece 22... Click locking portion 23... First slide locking portion 24... Slide locking portion 25... Slit 100... Capped container 200... Mold K... Cavity space

Claims

1. A cap unit that can be detachably attached to a container body having an open top, a cap body that closes the upper opening of the container body when fitted into the container body from the upper opening, The cap body includes an inside plug that is fitted into the container body from an upper opening of the container body; a waterproof packing that is integrally molded in close contact with the outer periphery of the lower end of the inside plug and seals the gap between the container body and the inside plug; The inside plug has a first recess having a shape corresponding to a first protrusion that protrudes horizontally inward from an upper end portion on an inner circumferential side of the watertight gasket, The inside plug has a boundary surface facing the upper surface of the watertight gasket, an inclined surface inclined upward from the outer side of the watertight gasket on the boundary surface, and an outer peripheral surface rising upward from the outer side of the inclined surface, The outer end of the boundary surface is located outside the outer upper end of the watertight packing, A cap unit characterized in that the distance by which the outer edge of the boundary surface extends beyond the outer upper edge of the watertight gasket is 2.0 mm or less.

2. 2. The cap unit according to claim 1, wherein the inclined surface is linearly inclined in a cross section along the axial direction of the inside plug.

3. 2. The cap unit according to claim 1, wherein the inclined surface is inclined in a curved shape in a cross section along the axial direction of the inside plug.

4. The cap unit according to claim 1, characterized in that the inner plug has a second recess having a shape corresponding to a second convex portion protruding upward from the lower end portion on the inner periphery of the watertight gasket.

5. The cap unit described in claim 4, characterized in that the inner plug has a third convex portion located between the first concave portion and the second concave portion and having a shape corresponding to a third concave portion formed between the first convex portion and the second convex portion of the water-stopping gasket.

6. The cap unit according to any one of claims 1 to 5, characterized in that the bottom surface of the inside plug is flush with the bottom surface of the watertight gasket.

7. A method for manufacturing the cap unit according to any one of claims 1 to 6, comprising: When the watertight gasket is integrally formed with the cap body using a mold that forms a cavity space having a shape corresponding to the watertight gasket having an undercut shape between the inside plug and the mold, Using a mold that is divided in the axial direction of the cap body, The cavity space is formed between the mold and the inside plug while the mold is in contact with the inclined surface, A method for manufacturing a cap unit, wherein the waterproof packing is molded from liquid silicone.

8. The cap unit according to any one of claims 1 to 6, A capped container comprising: a container body to which the cap unit is attached.

9. the cap unit has a third protrusion that protrudes downward so as to be in contact with the second protrusion, The cap unit according to claim 4, characterized in that the waterproof gasket has a flange portion located between the upper surface of the waterproof gasket and the lower end of the third convex portion in the height direction and protruding in the radial direction.

10. A cap unit that can be detachably attached to a container body having an open top, the cap unit closes the upper opening of the container body in a state where it is fitted into the inside of the container body from the upper opening of the container body, the cap unit has a waterproof gasket that is integrally molded in close contact with the outer periphery of the lower end side of the cap unit and seals the gap between the container body and the cap unit, The watertight gasket has a first convex portion that protrudes horizontally inward and a second convex portion that protrudes upward, the cap unit has a first recess that is recessed inward to correspond to the first protrusion, a second recess that is recessed upward to correspond to the second protrusion, and a third protrusion that protrudes downward to come into contact with the second protrusion, the cap unit has a boundary surface extending horizontally opposite to an upper surface side of the watertight gasket, an outer end of the boundary surface of the cap unit is located outside an upper end of the outer side of the watertight packing, The cap unit is characterized in that the waterproof gasket is located between the upper surface of the waterproof gasket and the lower end of the third convex portion in the height direction and has a flange portion that protrudes in the radial expansion direction.

11. The cap unit according to claim 10, wherein the cap unit has an inclined surface that is inclined upward from outside the waterproof packing at the boundary surface.

12. The cap unit described in claim 10, characterized in that the flange portion protrudes in a radial direction from the outer peripheral surface of the water-stopping gasket, and the outer peripheral surface is located radially inward from the outer end of the cap unit at the boundary surface.

13. The cap unit according to claim 10, wherein a lower surface of the cap unit is flush with a lower surface of the waterproof packing.

14. The cap unit according to claim 10, characterized in that the upper surface of the flange portion is located lower than the upper surface of the waterproof gasket, and the lower surface of the flange portion is located higher than the lower end of the third convex portion.

Images