JP2017178427A - Cap, metal mold and method for production of the cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cap capable of preventing dropout of a hermetic member, a metal mold and a method for production of the cap.SOLUTION: A cap 1 has a top plate part 21, and a skirt part 22 provided integrally via the top plate part 21 and a corner part 23, and is configured to be equipped with: a cap body 11 screwed onto the mouth part 110 of a can container 100; a slide layer 41 which is provided facing the top plate part 21 in addition to the cap body 11 and slides with the top plate part 21, and in which the outer peripheral side of a region facing the mouth part 110 is configured along the form of the corner part 23 when the cap body 11 is screwed with the can container 100; and a discoid hermetic member 12 provided integrally to the slide layer 41 and having a hermetic layer 42 sealing the mouth part 110 having a larger diameter than the slide layer 41.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cap for closing a can container, a mold, and a method for manufacturing the cap.

  Conventionally, a cap that seals the mouth portion of a can container has been provided with a sealing member that is formed of a resin material that is in close contact with the mouth portion on the inner surface of the cap body. Moreover, in order to reduce the opening torque at the time of opening of a cap, the technique which makes a cap main body and a sealing member non-bonding is known for such a cap (for example, refer patent document 1).

  Patent Document 1 discloses a configuration in which a liner serving as a sealing member includes a support layer facing the top surface portion of the cap body and a functional layer in close contact with the mouth portion of the container. Patent Document 1 discloses a technique for forming a liner by cutting a laminated sheet material obtained by laminating a support layer and a functional layer in a bonded state by coextrusion molding into a predetermined shape.

JP 2004-217295 A

  The sealing member described above has the following problems. That is, when manufacturing a sealing member by the above-mentioned method, the installation which cuts a liner from a lamination sheet material, and the installation which conveys the cut liner are needed. Moreover, the laminated sheet material from which the liner has been cut is discarded, and there is a problem that the yield is poor.

  For example, a method in which a molten resin material is supplied into the cap body and the resin material is molded into a predetermined sealing member shape using a mold is also conceivable. However, when the sealing member is molded in the cap body, the resin material shrinks when the resin material is cooled, even if the sealing member is molded in a configuration having an outer diameter comparable to the inner diameter of the cap body. For this reason, even if the projection for locking the sealing member is provided on the cap body, the outer diameter of the sealing member becomes smaller than the inner diameter of the cap body, and the sealing member may fall off.

  Then, an object of this invention is to provide the manufacturing method of the cap, metal mold | die, and cap which can prevent drop-off | omission of a sealing member.

  In order to solve the above problems and achieve the object, the cap, the mold and the method of manufacturing the cap of the present invention are configured as follows.

  As one aspect of the present invention, the cap has a top plate portion, and a skirt portion provided integrally with the top plate portion and a ring, and a curved corner portion, and the mouth portion of the can container A cap main body that is screwed to the cap body, and provided separately from the cap main body so as to face the top plate portion, and more than a portion that faces the mouth when the cap main body is screwed to the can container The outer peripheral side is configured along the shape of the corner portion, the sliding layer sliding with the top plate portion, and provided integrally with the sliding layer, and configured with a larger diameter than the sliding layer A disc-shaped sealing member having a sealing layer for sealing the mouth.

  As one aspect of the present invention, the mold includes a top plate portion, and a cap body in which a skirt portion provided integrally with the top plate portion and an annular ring and a curved corner portion is formed. A lower mold having a recess formed in the same shape as the outer shape of the top plate portion and the outer shape of at least a part of the corner portion of the molded product, and the inflow of the resin material is the same as the inner diameter of the skirt portion. A first upper mold for forming a sliding layer of a sealing member provided separately on the cap body, having an outer diameter that can be prevented, and having a groove along the shape of the corner on the end face; and the skirt portion A second upper mold for molding a sealing layer of the sealing member, the outer diameter of which is the same as the inner diameter of the sealing member or has an outer diameter that can prevent the inflow of the resin material.

  As one aspect of the present invention, a cap manufacturing method includes a top plate portion, and a cap main body in which a skirt portion provided integrally with the top plate portion and an annular shape and a curved corner portion is formed. The molded product is disposed in the recess of the lower mold having a recess formed in the same shape as the outer shape of the top plate portion and the outer shape of at least a part of the corner portion of the molded product constituting the mold, The first resin material is supplied to the plate portion, and the first resin material is provided by a first upper mold having an outer diameter equal to the inner diameter of the skirt portion and having a groove portion along the shape of the corner portion on the end surface. Forming a sliding layer of a sealing member provided separately on the cap body, supplying a second resin material to the sliding layer, and having an outer diameter equal to the inner diameter of the skirt portion; The second resin material is molded on the sliding layer by a second upper mold whose end surface is opposed to the lower mold. Constituting the sealing layer.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the cap which can prevent the drop-off | omission of a sealing member, the manufacturing method of a cap, and a metal mold | die.

The side view which shows typically the structure of the cap used for the can container which concerns on the 1st Embodiment of this invention in a partial cross section. The side view which shows the structure of the cap typically with a partial cross section. Explanatory drawing which shows 1 process of the 1st process of the manufacturing method of the cap. Explanatory drawing which shows the other process of the 1st process of the manufacturing method of the cap. Explanatory drawing which shows 1 process of the 2nd process of the manufacturing method of the same cap. Explanatory drawing which shows the other process of the 2nd process of the manufacturing method of the same cap. Sectional drawing which shows typically the principal part structure of the sealing member in the 1st process of the cap. Sectional drawing which shows typically the principal part structure of the sealing member in the 2nd process of the cap. The side view which shows typically the structure of the cap which concerns on the 2nd Embodiment of this invention in a partial cross section. The side view which shows typically the structure of the cap which concerns on the 3rd Embodiment of this invention in a partial cross section.

  Hereinafter, the structure of the cap 1 according to the first embodiment of the present invention, the method of manufacturing the cap 1, and the mold 200 used for manufacturing the cap 1 will be described with reference to FIGS.

  FIG. 1 is a side view schematically showing a configuration of the cap 1 used in the can container 100 according to the first embodiment of the present invention in a partial cross section, and FIG. 2 is a schematic cross section of the configuration of the cap 1. FIG. 3 is an explanatory view showing one step of the first step of the manufacturing method of the cap 1 and the configuration of the mold 200, and FIG. 4 is an explanatory view showing another step of the first step of the manufacturing method of the cap 1. 5 is an explanatory view showing the configuration of the mold 200 in one step of the second step of the manufacturing method of the cap 1. FIG. 6 is an explanatory view showing another step of the second step of the manufacturing method of the cap 1. FIG. Sectional drawing which shows typically the structure of the sliding layer 41 of the sealing member 12 in the 1st process of the cap 1, FIG. 8: shows the structure of the sliding layer 41 and the sealing layer 42 of the sealing member 12 in the 2nd process of the cap 1. FIG. It is sectional drawing shown typically. In FIG. 1 and FIG. 2, for convenience of explanation, the cross-sectional configuration of the cap 1 shows only the cross-sectional portion, and the side-view configuration is omitted.

  As shown in FIG. 1, the cap 1 is configured to be capable of sealing the mouth portion 110 by being tightly wound and fixed to the mouth portion 110 of the can container 100 in a crowned state.

  Here, the can container 100 is a so-called bottle-type container that contains a beverage or the like. For example, the can container 100 is comprised by metal materials, such as an aluminum alloy by which the resin films were laminated | stacked on both surfaces, and a surface-treated steel plate. The can container 100 is formed in a cylindrical shape having different outer diameters with one end reduced in diameter. Can container 100 has mouth part 110 which discharges the stored drink at one end. The mouth part 110 has a jaw part 111, a male screw part 112, and a curl part 113 on its outer peripheral surface from the bottom surface side to the end part of the can container 100.

  The jaw 111 is formed by projecting in an annular shape. The curled portion 113 is formed with a smaller diameter than the male screw portion 112. The curled portion 113 is configured to be smaller than the inner diameter of the cap 1. The curled portion 113 is configured by folding the end portion of the mouth portion 110 one or more times. The curled portion 113 constitutes an opening for discharging the beverage stored in the can container 100.

  The cap 1 includes a cap body 11 and a sealing member 12 provided separately in the cap body 11.

  The cap body 11 is made of a material in which a resin film layer is formed on a metal material such as an aluminum alloy. The cap main body 11 is configured by subjecting a thin, flat plate-like material to cup-shaped drawing, knurling, roll-on molding, and the like.

  The cap body 11 includes a disk-shaped top plate portion 21 and a cylindrical skirt portion 22 provided integrally with the peripheral edge portion of the top plate portion 21. The cap body 11 includes a top plate portion 21 and a skirt portion 22 that are integrally and continuously formed by an annular and curved corner portion 23.

  The top plate portion 21 is configured in a disc shape, and the main surface is configured as a flat surface. The skirt portion 22 is configured such that one end is continuous with the top plate portion 21 via the corner portion 23 and the other end is opened. The skirt portion 22 includes a plurality of knurl portions 31 having a vent slit 31 a, a female screw portion 32, and a tamper evidence band portion 33 from an end portion on the top plate portion 21 side to an end portion that opens.

  The knurled portion 31, the female screw portion 32, and the tamper evidence band portion 33 include a top plate portion 21, a cylindrical skirt portion 22 in which the knurled portion 31, the female screw portion 32, and the tamper evidence band portion 33 are not formed, and a corner. A cup-shaped molded product 99 composed of the portion 23 is formed by processing such as knurling molding or roll-on molding.

  The knurl part 31 has a vent slit 31 a and protrudes from the inner peripheral surface of the skirt part 22. The female screw portion 32 is configured to be screwable with the male screw portion 112 of the can container 100. The tamper evidence band portion 33 is engaged with the jaw portion 111 of the can container 100 in the direction in which the cap 1 is separated from the can container 100 and in the axial direction of the cap 1. Further, the tamper evidence band portion 33 has a break portion 33 a that is broken when the cap 1 is opened and is detached from the skirt portion 22.

  The sealing member 12 is configured separately from the cap body 11. The sealing member 12 is configured in a disc shape having an outer diameter larger than the diameter of the inscribed circle of the knurl portion 31 provided in the skirt portion 22 of the cap body 11. The sealing member 12 is provided integrally with the cap body 11 by engaging with a vent slit 31a of the knurl portion 31 protruding in the radial direction from the inner peripheral surface of the skirt portion 22 in the axial direction of the cap body 11.

  The sealing member 12 includes a disk-shaped sliding layer 41 and a disk-shaped sealing layer 42 integrally laminated on the sliding layer 41. The sealing member 12 is configured by integrally forming the sliding layer 41 and the sealing layer 42 with different resin materials. The sealing member 12 includes a flat plate portion 12a having a uniform thickness, and a curved surface portion 12b having a curved outer peripheral edge on the top plate portion 21 side. In other words, the sealing member 12 is formed in a disc shape, and the ridge portion on the top plate portion 21 side is configured by a curved surface having a predetermined curvature.

  The sliding layer 41 is made of a resin material having a relatively high hardness (hard). Moreover, the sliding layer 41 is comprised with the resin film layer of the cap main body 11, and the resin material which does not have adhesiveness and adhesiveness. That is, the sliding layer 41 is configured to be non-adhesive with the top plate portion 21 and to be slidable on the top plate portion 21 in a state in contact with the top plate portion 21.

  Examples of the resin material used for the sliding layer 41 include olefin resins such as polypropylene resin and polyethylene resin, polyester resins such as polyethylene terephthalate, styrene resins, and acrylic resins. In the present embodiment, the sliding layer 41 is made of, for example, polypropylene resin. Note that pigments, lubricants, softeners, and the like can be added as appropriate to the resin material used for the sliding layer 41.

  The sliding layer 41 is provided separately from the cap body 11 so as to face the top plate portion 21 of the cap body 11. The sliding layer 41 is configured to be slidable with the top plate portion 21 of the cap body 11 by the resin material used. The sliding layer 41 is configured in a disk shape. The outer diameter of the sliding layer 41 is smaller than the inner diameter of the skirt portion 22, substantially the same diameter as the inscribed circle of the knurled portion 31, or slightly smaller than the inscribed circle, and the curled portion 113 of the mouth portion 110. The outer diameter is larger than the outer diameter.

  The sliding layer 41 includes a first flat plate portion 41a having a uniform thickness, and a first curved surface portion 41b whose outer peripheral edge on the top plate portion 21 side is curved along the shape of the corner portion 23 of the cap body 11. I have. The first flat plate portion 41a has a uniform thickness from the center of the sliding layer 41 to the outer peripheral side of the portion facing the curled portion 113 of the mouth portion 110. The first curved surface portion 41b is configured such that the thickness of the portion from the outer peripheral side to the outer peripheral edge is substantially constant with respect to the portion of the mouth portion 110 facing the curled portion 113.

  The sealing layer 42 is made of a resin material having relatively low hardness (soft) and softer than the sliding layer 41. Examples of the resin material used for the sealing layer 42 include an olefin resin, a polyester resin, a styrene resin, an acrylic resin, and the like, and more preferably, a blend material of a styrene elastomer and a polypropylene resin, a low density polyethylene and a styrene resin. Examples include elastomer blend materials, polyester elastomers, and the like. In the present embodiment, the sealing layer 42 is made of, for example, a mixed material of styrene elastomer and polypropylene resin. Note that pigments, lubricants, softeners, and the like can be added as appropriate to the resin material used for the sealing layer 42.

  The sealing layer 42 is integrally provided on the main surface of the sliding layer 41 on the side facing the mouth portion 110. The sealing layer 42 is configured in a disk shape. The outer diameter of the sealing layer 42 is smaller than the inner diameter of the skirt portion 22, larger than the inscribed circle of the knurled portion 31, and larger than the outer diameter of the curled portion 113 of the mouth portion 110. The That is, the outer diameter of the sealing layer 42 is larger than the outer diameter of the sliding layer 41 and larger than the inscribed circle of the knurled portion 31.

  The sealing layer 42 includes a second flat plate portion 42a having a uniform thickness and a second curved surface portion 42b in which the outer peripheral surface of the outer peripheral edge on the top plate portion 21 side is a curved surface. The main surface of the second flat plate portion 42a facing the curled portion 113 is a flat surface. The thickness of the second flat plate portion 42a is uniform from the center of the sealing layer 42 to the outer peripheral side of the portion facing the curled portion 113 of the mouth portion 110. For example, the second flat plate portion 42 a is configured to have the same diameter as the first flat plate portion 41 a of the sliding layer 41. The 2nd flat plate part 42a comprises the flat plate part 12a of the sealing member 12 with the 1st flat plate part 41a. In the present embodiment, the first flat plate portion 41a and the second flat plate portion 42a are set to the same thickness.

  The second curved surface portion 42b has, for example, a main surface that is flush with the main surface facing the curled portion 113 of the second flat plate portion 42a. As for the 2nd curved surface part 42b, the outer surface from an outer peripheral side to an outer periphery rather than the site | part facing the curl part 113 of the opening | mouth part 110 curves along the shape of the corner | angular part 23 of the cap main body 11. FIG. The second curved surface portion 42b is stacked on the first curved surface portion 41b and covers the curved surface on the top plate portion 21 side of the first curved surface portion 41b, that is, the outer peripheral surface of the first curved surface portion 41b. The 2nd curved surface part 42b comprises the curved surface part 12b of the sealing member 12 with the 1st curved surface part 41b.

Next, a mold 200 for manufacturing the sealing member 12 of the cap 1 will be described.
As shown in FIGS. 3 and 5, the mold 200 is connected to the lower mold 201, the upper mold 202 movable in one direction with respect to the lower mold 201, and the upper mold 202. And a driving device 203 that moves the mold 202. 3 to 6, the configuration of the mold 200 and detailed symbols are shown only in FIGS. 3 and 5, and the driving device 203 and detailed symbols are omitted in FIGS. 4 and 6.

  The lower mold 201 is configured to be able to hold a molded product 99 of the cap body 11 that is being molded. The lower mold 201 has a recess 201 a that holds the molded product 99.

  The depression 201 a is configured to be able to support at least a part of the outer surface of the top plate portion 21 and the outer peripheral surface of the corner portion 23 of the molded product 99. In other words, the depression 201 a is configured in the same shape as a part of the outer shape of the top plate portion 21 and the outer shape of the corner portion 23 of the molded product 99.

  The depth of the recess 201a, in other words, at least the height from the upper surface of the lower mold 201 to the bottom surface of the recess 201a is the same height as the sum of the thickness of the top plate portion 21 and the thickness of the sealing member 12. What is necessary is just to be comprised. For this reason, the depression 201a may be configured in the same shape as the outer shape of the top plate portion 21, the outer shape of the corner portion 23, and a part of the outer shape of the skirt portion 22.

  The upper mold 202 includes a first upper mold 211 that molds the sliding layer 41 of the sealing member 12, a second upper mold 212 that molds the sealing layer 42 of the sealing member 12, a first upper mold 211, and Movable molds 213 used for the second upper mold 212, respectively. The upper mold 202 is a mold that can be moved by the driving device 203.

  In the upper mold 202, the first upper mold 211 and the movable mold 213 are used when the sliding layer 41 is molded, and the second upper mold 212 and the movable mold 213 are used when the sealing layer 42 is molded. Used.

  The first upper mold 211 includes a cylindrical first molding portion 211a, a first mounting portion 211b provided on the outer peripheral surface on the other end side of the first molding portion 211a, and the other end side of the first molding portion 211a. And a first restricting portion 211c provided on the inner peripheral surface. The first upper mold 211 is configured so that the end surface of the first molding part 211a is separated from the molded product 99 arranged in the lower mold 201 from the inner surface of the top plate part 21 of the molded product 99 from the inner surface of the sliding layer 41. It is configured to be movable to a position separated by the same distance as the thickness.

  As for the 1st shaping | molding part 211a, the surface of the front-end | tip is comprised by planar shape. The first molding portion 211a has an end surface on one end side of the first molding portion 211a facing the lower mold 201, and has a groove portion 211d along the shape of the corner portion 23 on the outer peripheral edge. The outer diameter of the first molding portion 211a is configured to be the same as the inner diameter of the skirt portion 22 or a small diameter that does not allow the resin material to flow. Here, the slightly small diameter that does not allow the resin material to flow in is appropriately determined according to various conditions such as the viscosity, temperature, and pressure of the resin material to be used. That is, the slightly small diameter that does not allow the resin material to flow in is such that the resin material can be prevented from flowing between the first molding portion 211a and the skirt portion 22 when the resin material is pressed by the mold 200. The diameter at which clearance can be obtained.

  The first attachment portion 211b is provided on the outer peripheral surface on the other end side of the first molding portion 211a. The first attachment portion 211b is connected to the driving device 203. The 1st control part 211c is comprised so that the movement amount of the movable mold | type 213 can be controlled. The first restricting portion 211c is, for example, a movable mold 213 with an end surface formed by forming an inner diameter on the other end side of the first molding portion 211a larger than an inner diameter of the other portion of the first molding portion 211a. The amount of movement is regulated.

  The second upper mold 212 is provided on the outer peripheral surface on the other end side of the second molding section 212a and the cylindrical second molding section 212a having a planar end surface facing the lower mold 201. And a second restricting portion 212c provided on the inner peripheral surface on the other end side of the second molding portion 212a. The second upper mold 212 has a thickness of the sliding layer 41 from the inner surface of the top plate portion 21 of the molded product 99 from a position where the end surface of the second molded portion 212a is separated from the molded product 99 arranged in the lower mold 201. It is configured to be movable to a position separated by the same distance as the sum of the thickness and the thickness of the sealing layer 42.

  The 2nd shaping | molding part 212a is comprised by the cylindrical shape by which the end surface of one end side and the ridge part of an outer peripheral surface are not chamfered. In other words, the second upper mold 212 does not include the groove 211d of the first molding part 211a of the first upper mold 211. As for the 2nd shaping | molding part 212a, the surface of the front-end | tip is comprised by planar shape. The outer diameter of the second molding part 212a is configured to be the same diameter as the inner diameter of the skirt part 22 or slightly smaller so that the resin material does not flow. Here, the slightly small diameter that does not allow the resin material to flow in is appropriately determined according to various conditions such as the viscosity, temperature, and pressure of the resin material to be used. That is, the slightly small diameter that does not allow the resin material to flow in is such that the resin material can be prevented from flowing between the second molding portion 212a and the skirt portion 22 when the resin material is pressed by the mold 200. The diameter at which clearance can be obtained.

  The second attachment portion 212b is provided on the outer peripheral surface on the other end side of the second molding portion 212a. The second attachment portion 212b is connected to the driving device 203. The 2nd control part 212c is comprised so that the movement amount of the movable mold | type 213 can be controlled. For example, the second restricting portion 212c is configured such that the inner diameter of the second molding portion 212a is larger than the inner diameter of the other portion of the second molding portion 212a. The amount of movement is regulated.

  The movable mold 213 includes a cylindrical third molding part 213a having a planar end surface facing the lower mold 201, and a third attachment part provided on the other end side of the third molding part 213a. 213b and a regulated portion 213c provided on the outer peripheral surface on the other end side of the third molding portion 213a.

  The third molding part 213a is formed in a columnar shape, and the outer diameter thereof is the same as the inner diameter of the first molding part 211a of the first upper mold 211 and the inner diameter of the second molding part 212a of the second upper mold 212. Configured to the diameter. The third molding portion 213a has a flat tip surface.

  The third attachment portion 213b is connected to the driving device 203. The regulated portion 213c is an outer peripheral surface of the third molding portion 213a, and comes into contact with the first regulating portion 211c of the first upper mold 211 or the second regulating portion 212c of the second upper mold 212. The end surface of the third molding part 213a is provided at a position that is flush with the end surface of the first molding part 211a or the end surface of the second molding part 212a.

  The driving device 203 is configured to be able to move the first upper mold 211, the second upper mold 212, and the movable mold 213 in one direction with respect to the lower mold 201 within a predetermined distance range. Specifically, the driving device 203 includes a position where the end surface of the first molding portion 211a is spaced from the end portion of the skirt portion 22 of the molded product 99 disposed in the lower mold 201, and the end surface of the first molding portion 211a. Is configured such that the first upper mold 211 can be moved along the axial direction of the molded product 99 between the positions separated from the inner surface of the top plate portion 21 of the molded product 99 by the same distance as the thickness of the sliding layer 41. Is done.

  The driving device 203 includes a position where the end surface of the second molding portion 212 a is spaced from the end surface of the skirt portion 22 of the molded product 99 disposed in the lower mold 201, and the end surface of the second molding portion 212 a is that of the molded product 99. The second upper mold 212 is moved along the axial direction of the molded product 99 between the positions separated from the inner surface of the top plate portion 21 by the same distance as the sum of the thickness of the sliding layer 41 and the thickness of the sealing layer 42. , Configured to be movable.

  Further, the driving device 203 moves the movable mold 213 in the same process as the movement direction of the first upper mold 211 and the second upper mold 212 in a process different from the first upper mold 211 and the second upper mold 212. It is configured to be movable in the direction. The driving device 203 includes, for example, a control unit, and the control unit drives the first upper mold 211, the second upper mold 212, and the movable mold 213 by a predetermined operation using a program stored in advance. .

Next, a method for manufacturing the cap 1 using the mold 200 configured as described above will be described with reference to FIGS.
First, a molded product in which the top plate portion 21, the skirt portion 22, and the corner portion 23 are formed by drawing a material in which a resin film layer is formed on a metal material such as a thin flat aluminum alloy into a cup shape. 99 is manufactured.

  Next, the molded product 99 is placed in the recess of the lower mold 201. Next, as the first step, the sliding layer 41 of the sealing member 12 is formed. Specifically, first, as shown in step ST11 of FIG. 3, the driving device 203 drives the first upper mold 211 and the movable mold 213 to place the first upper mold 211 and the movable mold 213 in the initial positions. To place. Here, the initial position is a position where the first upper mold 211 is separated from the molded product 99 arranged in the lower mold 201, and the end surface of the movable mold 213 is separated from the end surface of the first molding portion 211a. This is the retreat position. Next, the melted first resin material 151 for molding the sliding layer 41 is supplied to the central portion of the top plate portion 21 of the molded product 99 by a supply device or the like.

  Next, as shown in step ST12 of FIG. 4, the driving device 203 maintains the initial position state so that the end surface of the first molded portion 211a is slid from the inner surface of the top plate portion 21 of the molded product 99. The first upper mold 211 and the movable mold 213 are moved to a position separated by the same distance as the thickness of 41.

  Thereby, the first upper mold 211 forms a gap that becomes the thickness of the sliding layer 41 between the end surface of the first molding part 211 a and the surface of the top plate part 21 of the molded product 99. At this time, since the end surface of the movable mold 213 is retracted from the end surface of the first molding part 211a, the first resin material 151 is pressed by the movable mold 213 and has a shape thicker than the thickness of the sliding layer 41. Become.

  Next, as shown in step ST13, the driving device 203 moves the movable mold 213 so that the end surface of the movable mold 213 is flush with the end surface of the first molding part 211a. The movable mold 213 is such that the regulated portion 213c comes into contact with the first regulating portion 211c of the first upper mold 211 and its movement is regulated so that the end surface of the third molding portion 213a becomes the end surface of the first molding portion 211a. And become the same. Thereby, the 1st resin material 151 is pressed by the movable mold | type 213, and as shown with the dashed-two dotted line in FIG. 7, the inner surface of the top-plate part 21 and the corner | angular part 23 of the molded article 99, and the 1st molding part 211a. The gap between the end surface and the end surface of the movable mold 213 is filled, and compression molding is performed in substantially the same shape as the sliding layer 41.

  That is, the first resin material 151 is formed into the shape of the first flat plate portion 41a by the top plate portion 21, the end surface of the first molding portion 211a and the end surface of the third molding portion 213a, and the groove portion of the corner portion 23 and the first molding portion 211a. 211d is formed into the shape of the first curved surface portion 41b.

  Next, the drive unit 203 retracts the movable mold 213 from the molded product 99 as shown in step ST14, and then retracts the first upper mold 211 and the movable mold 213 from the molded product 99 as shown in step ST15. Let The compression-molded first resin material 151 is naturally cooled or cooled by a cooling device to solidify the first resin material 151. As the first resin material 151 is cooled, the first resin material 151 contracts as shown by a solid line in FIG. 7, and the formed sliding layer 41 becomes smaller than the inner diameter of the cap body 11. The sliding layer 41 is formed by these first steps.

  Next, as a second step, the sealing layer 42 is formed on the main surface of the sliding layer 41. Specifically, first, as shown in step ST21 in FIG. 5, the driving device 203 drives the second upper mold 212 and the movable mold 213 to place the second upper mold 212 and the movable mold 213 in the initial positions. To place. Here, the initial position is a position where the second upper mold 212 is separated from the molded product 99 disposed in the lower mold 201, and the end surface of the movable mold 213 extends from the end surface of the second molding portion 212a. This is the retreat position. Next, the molten second resin material 152 for forming the sealing layer 42 is supplied to the central portion of the sliding layer 41 formed on the top plate portion 21 of the molded product 99 by a supply device or the like.

  Next, as shown in step ST <b> 22 of FIG. 6, the driving device 203 maintains the initial position state so that the end surface of the second molded portion 212 a is slid from the inner surface of the top plate portion 21 of the molded product 99. The second upper mold 212 and the movable mold 213 are moved to a position separated by the same distance as the thickness of 41 and the sealing layer 42.

  As a result, the second upper mold 212 forms a gap corresponding to the thickness of the sealing layer 42 between the end surface of the second molding part 212 a and the surface of the top plate part 21 of the molded product 99. At this time, since the end surface of the movable mold 213 is retracted from the end surface of the second molding part 212a, the second resin material 152 is pressed by the movable mold 213 and becomes thicker than the thickness of the sealing layer 42. .

  Next, as shown in step ST23, the driving device 203 moves the movable mold 213 so that the end surface of the movable mold 213 is flush with the end surface of the second molding part 212a. The movable mold 213 is such that the regulated portion 213c comes into contact with the second regulating portion 212c of the second upper mold 212 and its movement is regulated, so that the end surface of the third molding portion 213a becomes the end surface of the second molding portion 212a. And become the same. As a result, the second resin material 152 is pressed by the movable mold 213, and the inner surfaces of the sliding layer 41 and the corner portion 23 existing on the top plate portion 21 of the molded product 99, as shown by a two-dot chain line in FIG. And the end surface of the second molding part 212a and the end surface of the movable mold 213 are filled, and compression-molded in substantially the same shape as the sealing layer 42.

  At this time, the sliding layer 41 is elastically deformed by the pressure of the second resin material 152, and as shown by a two-dot chain line in FIG. 8, the main surface is substantially flat and the first curved surface portion 41 b is It deforms so as to protrude slightly outward in the radial direction. Since the first curved surface portion 41b is configured to have a substantially constant shape thickness along the corner portion 23, deformation of the first curved surface portion 41b is hindered, and the first curved surface portion 41b and the corner portion 23 are prevented from being deformed. There is a gap in

  Therefore, the second resin material 152 constituting the sealing layer 42 wraps around the outer peripheral side of the sliding layer 41 beyond the first curved surface portion 41 b and enters the gap between the first curved surface portion 41 b and the corner portion 23 of the sliding layer 41. invade.

  That is, the second resin material 152 is formed into the shape of the second flat plate portion 42a by the first flat plate portion 41a of the sliding layer 41, the end surface of the second molded portion 212a, and the end surface of the third molded portion 213a. The first curved surface portion 41b and the groove portion 212d of the second molding portion 212a are respectively molded into the shape of the second curved surface portion 42b. As a result, the outer diameter of the sealing layer 42 is larger than the outer diameter of the sliding layer 41.

  Next, the drive unit 203 retracts the movable mold 213 from the molded product 99 as shown in step ST24, and then retracts the second upper mold 212 and the movable mold 213 from the molded product 99 as shown in step ST25. Let The compression-molded second resin material 152 is naturally cooled or cooled by a cooling device to solidify the second resin material 152. 8, the sliding layer 41 contracts by retracting the second upper mold 212 and the movable mold 213, and the second resin material 152 contracts by cooling the second resin material 152. The molded sealing layer 42 is smaller than the inner diameter of the cap body 11.

  However, since the second curved surface portion 42b of the sealing layer 42 is formed around the first curved surface portion 41b, the shrinkage of the second curved surface portion 42b is suppressed by the first curved surface portion 41b that has already been cooled and solidified. Is done. In addition, the shrinkage of the second curved surface portion 42b is substantially the shrinkage of the second resin material 152 that has wrapped around the first curved surface portion 41b, and therefore the shrinkage amount is also small. As a result, the second curved surface portion 42b has a smaller amount of shrinkage, so that the outer diameter of the second curved surface portion 42b shrinks due to cooling and becomes smaller than the inner diameter of the cap body 11, so that the inscribed circle of the vent slit 31a of the knurled portion 31 The shape is larger than the diameter. The sealing layer 42 is formed on the sliding layer 41 by these second steps.

  By these first step and second step, the sealing member 12 is molded separately in the molded product 99. Next, the sealing member 12 is taken out from the molded product 99, and the knurled portion 31 and the tamper evidence band portion 33 are molded into the molded product 99 by knurling or the like as shown in FIG. Next, the sealing member 12 is inserted into the cap body 11 formed with the knurled portion 31 and the tamper evidence band portion 33 in a posture in which the curved surface portion 12 b faces the top plate portion 21 side of the cap body 11. Thereby, the cap 1 which is not attached to the can container 100 is formed.

  When sealing the cap 1 with the can container 100, the can container 100 is filled with a beverage or the like, covered with the cap 1, and the sealing layer 42 is in close contact with the curled portion 113. Next, the female screw portion 32 is formed along the shape of the male screw portion 112 of the can container 100 by roll-on molding or the like, and the tamper evidence band portion 33 is formed so that the tamper evidence band portion 33 is engaged with the jaw portion 111. Is molded. By these steps, the cap 1 is clamped and fixed to the mouth 110 of the can container 100, and a can product in which the can container 100 is sealed with the cap 1 is manufactured.

  According to the cap 1 configured as described above, the sealing member 12 is provided with the first curved surface portion 41 b along the corner portion 23 on the outer peripheral edge of the sliding layer 41, and the second curved surface portion 42 b of the sealing layer 42. The outer diameter is formed larger than the outer diameter of the first curved surface portion 41b. For this reason, the sealing member 12 can suppress the shrinkage of the second curved surface portion 42 b after molding, and the outer diameter thereof can be larger than the diameter of the inscribed circle of the knurled portion 31. As a result, the sealing layer 42 of the sealing member 12 engages with the knurled portion 31, so that the sealing member 12 is reliably engaged with the knurled portion 31 when the sealing member 12 moves in the direction of dropping from the cap body 11. Stopped. As a result, the sealing member 12 can be prevented from falling off from the cap body 11.

  Further, after the sliding layer 41 is formed, the sliding layer 41 contracted by cooling may be eccentric with respect to the axis of the cap body 11, but the sealing member 12 is formed after the sliding layer 41 is formed. In this configuration, the sealing layer 42 having a larger diameter is formed. For this reason, even if the eccentricity occurs in the sliding layer 41, after the sealing layer 42 is formed at the corner 23 of the cap body 11, the sealing layer 42 is cooled in a state of covering the sliding layer 41, and sealed. The layer 42 contracts by substantially the same amount all around. As a result, the sealing member 12 can maintain centering properties with respect to the cap body 11.

  Further, the sealing member 12 can be molded in the molded product 99 constituting the cap body 11, and equipment for cutting the sealing member 12 becomes unnecessary. Further, the first resin material 151 and the second resin material 152 used for the production may be in an amount constituting the sealing member 12. For this reason, it becomes possible to reduce the installation cost and manufacturing cost of the sealing member 12.

  Moreover, the sealing member 12 has the curved surface part 12b in the outer periphery side by shape | molding in the molded article 99. FIG. For this reason, after molding the sealing member 12 with the molded product 99, the sealing member 12 is taken out, and when the sealing member 12 is inserted into the molded cap body 11, the curved surface portion 12b guides the insertion of the sealing member 12. Therefore, it has high assemblability.

  As described above, in the cap 1 according to the first embodiment of the present invention, the sealing member 12 is detached from the cap body 11 by making the outer diameter of the sealing layer 42 larger than the outer diameter of the sliding layer 41. Can be prevented.

  In addition, this invention is not limited to embodiment mentioned above. For example, in the above-described example, the sealing member 12 has been described with the configuration in which the main surface of the sealing layer 42 that contacts the curled portion 113 of the mouth portion 110 of the can container 100 is a flat surface, but is not limited thereto. For example, as shown in the sealing member 12A according to the second embodiment shown in FIG. 9, the sealing layer 42A may have a configuration in which a portion 42c contacting the curled portion 113 is thicker than the second flat plate portion 42a. With this configuration, the thickness of the second flat plate portion 42a can be reduced, and therefore the second resin material 152 used for the sealing layer 42A is reduced. As a result, the manufacturing cost of the sealing member 12A can be reduced. In the sealing layer 42A, the second resin material 152 of the sealing layer 42A is reduced at the time of manufacture, and the second restriction is made so that the end surface of the movable mold 213 slightly protrudes from the end surface of the second upper mold 212. It may be configured to change the shape of the portion 212c.

  Further, for example, as shown in the sealing member 12B according to the third embodiment shown in FIG. 10, the sealing layer 42 </ b> B has a portion that contacts the curled portion 113 and an inner peripheral surface or an outer peripheral surface of the curled portion 113 or both of them. A configuration in which an annular protrusion 42d that abuts may be provided. Such a sealing layer 42B may have a configuration in which a recess having the same shape as the protrusion 42d is provided on the end surface of the second molding portion 212a of the second upper mold 212.

  Moreover, although the sealing member 12 demonstrated the structure which laminates | stacks the sealing layer 42 on the sliding layer 41 in the example mentioned above, it is not limited to this. For example, the sealing member 12 may have a configuration in which an intermediate layer is provided with another resin material between the sliding layer 41 and the sealing layer 42. Further, the driving device 203 of the mold 200 is connected to the upper mold 202, but may be connected to the lower mold 201, and the sealing member 12 may be manufactured by moving the lower mold 201. In addition, various modifications can be made without departing from the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Cap, 11 ... Cap main body, 12 ... Sealing member, 12a ... Flat plate part, 12b ... Curved surface part, 21 ... Top plate part, 22 ... Skirt part, 23 ... Corner | angular part, 31 ... Knurl part, 31a ... Vent slit, 32 ... Female screw part, 33 ... Tamper evidence band part, 33a ... Breaking part, 41 ... Sliding layer, 41a ... First flat plate part, 41b ... First curved surface part, 42 ... Sealing layer, 42a ... Second flat plate part, 42b ... second curved surface part, 99 ... molded product, 100 ... can container, 110 ... mouth part, 111 ... jaw part, 112 ... male screw part, 113 ... curl part, 200 ... mold, 201 ... lower mold, 202 DESCRIPTION OF SYMBOLS ... Upper metal mold | die 203 ... Drive apparatus 211 ... 1st upper metal mold | die 211a ... 1st shaping | molding part, 211b ... 1st attachment part, 211c ... 1st control part, 211d ... Groove part, 212 ... 2nd upper metal mold | die , 212a ... second molding part, 212b ... second mounting part, 2 2c ... second restricting portion, 213 ... movable die, 213a ... third molding portion, 213b ... third mounting portion, 213c ... the restricted portion.

Claims (8)

A cap body having a top plate portion, and a skirt portion provided integrally with the top plate portion and an annular ring-shaped corner portion, and screwed into the mouth portion of the can container;
The cap body is provided separately from the top plate portion, and the outer peripheral side of the portion facing the mouth portion follows the shape of the corner portion when the cap body is screwed with the can container. And a sliding layer that slides with the top plate portion, and a sealing layer that is provided integrally with the sliding layer and seals the mouth portion that has a larger diameter than the sliding layer. A disc-shaped sealing member;
A cap characterized by comprising.   The cap according to claim 1, wherein the sealing layer covers an outer peripheral surface of the sliding layer. The outer shape of the top plate portion of the molded product constituting the top plate portion, and the cap body in which the skirt portion provided integrally with the top plate portion and an annular ring-shaped corner portion is formed. And a lower mold having a recess formed in the same shape as the outer shape of at least a part of the corner,
A sliding layer of a sealing member provided separately from the cap body, having an outer diameter that is the same as the inner diameter of the skirt portion or has an outer diameter that can prevent the inflow of a resin material, and has a groove portion along the shape of the corner portion on the end face. A first upper mold for molding
A second upper mold for molding a sealing layer of the sealing member, having an outer diameter that is the same as the inner diameter of the skirt portion or has an outer diameter that can prevent the inflow of a resin material, and whose end face is opposed to the lower mold;
A mold characterized by comprising.   The groove portion is provided in the first upper mold so as to face an outer peripheral side of a portion of the top plate portion facing the mouth portion of the can container when the cap body is screwed with the can container. The mold according to claim 3.   The mold according to claim 3, wherein the depth of the recess is configured to be the same height as the sum of the thickness of the top plate portion and the thickness of the sealing member. The outer shape of the top plate portion of the molded product constituting the top plate portion, and the cap body in which the skirt portion provided integrally with the top plate portion and an annular ring-shaped corner portion is formed. And placing the molded product in the depression of the lower mold having a depression formed in the same shape as the outer shape of at least a part of the corner,
Supplying the first resin material to the top plate,
The first resin material is molded by a first upper mold having an outer diameter that is the same as the inner diameter of the skirt portion, and a groove portion along the shape of the corner portion on the end surface, and is separately formed on the cap body. Constituting a sliding layer of the sealing member provided,
Supplying a second resin material to the sliding layer;
Forming the second resin material with a second upper mold having the same outer diameter as the inner diameter of the skirt portion and having an end surface facing the lower mold to form a sealing layer on the sliding layer;
A cap manufacturing method characterized by the above.   The groove portion is provided in the first upper mold so as to face an outer peripheral side of a portion of the top plate portion facing the mouth portion of the can container when the cap body is screwed with the can container. The method for manufacturing a cap according to claim 6.   The method of manufacturing a cap according to claim 6, wherein the depth of the recess is configured to be the same height as the sum of the thickness of the top plate portion and the thickness of the sealing member.