JP2011173594A - Easily unsealable lid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an unsealing line torn by pulling up a pull-ring from being broken during forming when an easily unsealable container lid consisting of a metal-made lid shell body is formed. <P>SOLUTION: A pair of opening introducing lines 21 and 21 consisting of scores formed by carving from an inner face are extended in the peripheral direction on a curved part 13 being a boundary part between a top plate part 7 of a metal-made lid shell body 1 and a skirt part 9 so as to pinch the top plate part therebetween. In addition, the end part of the tongue piece side at least positions above the lower part of the skirt part 9. From both root parts of the tongue piece 11 continuously connected with the lower end of the skirt part 9 and connected with a pull ring 3, opening starting lines 23 and 23 extending upward on the skirt part 9 toward a curved part 13, but at least not extending in the peripheral direction of the curved part 13, are respectively provided, and it is characterized in that the opening starting line 23 consists of a score formed by carving from the outer face. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an easily openable lid, and more specifically, includes a metal lid shell, a pull ring, and a liner material, and easily opens the lid by cutting an opening guide line provided on the metal lid shell. It relates to the improvement of an openable lid.

  Conventionally, as an easy-open container lid provided in a container such as a bottle, a metal lid shell body and a pull ring are provided, and a liner material is provided on the inner surface of the metal lid shell body. A structure in which a pair of opening guide lines is provided depending on the score is widely used. In such an easy-open container lid, by pulling up the pull ring, the opening guide line is torn, and as a result, the container lid can be easily detached from the container without using a special opening device. .

  By the way, in the easily openable container lid having the above-described structure, a tongue piece extending further downward is formed at the lower end of the skirt portion of the metal lid shell, and the tongue piece is made of resin or metal. The thing of the structure which formed the made pull ring is used widely (for example, refer patent document 1). That is, when pulling up the pull ring upward to tear the opening guide line formed in the metal lid shell, if the pull ring is provided directly at the lower end of the skirt, Since the connecting portion between the pull ring and the pull ring is bent, the pull ring is easily broken. However, if a tongue piece extending further downward from the lower end of the skirt portion is provided and a pull ring is provided on the tongue piece, the portion that is bent when the pull ring is pulled up is the base portion of the tongue piece (the tongue Therefore, the pull ring can be effectively prevented from being torn off.

  A pair of opening guide lines provided on the metal lid shell extends from the top plate portion of the metal lid shell to the skirt portion, and the pull ring is pulled up to form the opening formed on the skirt portion. The guide wire is torn, and subsequently the opening guide wire formed on the top plate portion is torn. Therefore, each of the pair of opening guide lines extending to the skirt part extends to both ends of the base part of the tongue piece, and the pulling up of the pull ring smoothly tears the opening guide line from the skirt part. It is like that.

Japanese Unexamined Patent Publication No. 63-138956

  By the way, a pair of opening guide lines provided on the metal lid shell (top plate portion and skirt portion) of the easily openable container lid is formed from the outer surface or the inner surface of the metal lid shell body using an appropriate jig. For example, in Patent Document 1 described above, as shown in FIGS. 22 and 23, it is formed by engraving from the inner surface.

  However, even when the opening guide wire is formed by either the engraving from the outer surface or the engraving from the inner surface, the opening guide wire is damaged when the metal plate is formed into the shape of the container lid. Inconvenience often occurred. That is, the easy-open container lid forms a pair of opening guide lines by engraving from the side that becomes the outer surface or inner surface of the container lid at a predetermined position of the flat plate-shaped metal plate, and when the metal plate is punched in this state At the same time, a metal lid shell is formed by drawing or bending, and when a resin pull ring is provided, a resin pull ring is formed on the tongue of the metal lid shell by insert molding or the like. It is manufactured by fixing a liner material to the inner surface of the top plate portion of the metal lid shell. Thus, when manufacturing an easily openable container lid, a metal lid shell body (container having a top plate portion, a skirt portion, and a tongue piece is obtained by drawing or bending a flat metal plate punched into a predetermined shape. When forming into a lid shape, there is a problem that the portion where the opening guide wire is formed is often damaged. It has been found that this phenomenon occurs particularly when the opening guide line extending in the circumferential direction of the top plate portion is provided as far as possible in order to facilitate the removal of the container lid from the container.

  Accordingly, an object of the present invention is to provide an easily openable container lid in which a pair of opening guide lines to be torn by pulling up of the pull ring is formed on the top plate portion and the skirt portion of the metal lid shell body. To provide an easily openable container lid having a structure in which breakage of a portion where an opening guide line is formed is effectively prevented when a punched metal plate is drawn or bent into a shape of a container lid. is there.

According to the present invention, a metal lid shell comprising a top plate portion, a skirt portion connected to the top plate portion, and a tongue piece provided on a part of the skirt portion so as to protrude from the edge thereof; An easily openable lid comprising: a pull ring extending from a lower end portion of the metal lid; and a liner material fixed to the inner surface of the top plate portion of the metal lid shell.
A pair of opening guide lines composed of scores formed by engraving from the inner surface are provided around the curved portion, which is the boundary between the top plate portion and the skirt portion of the metal lid shell body, with the top plate portion interposed therebetween. And the end of the pair of opening guide lines on the tongue piece side is located at least above the lower end of the skirt,
An opening start line extending from the both bases of the tongue piece upwardly toward the curved portion, respectively, but not extending in the circumferential direction of the curved portion is provided. An easy-open lid is provided in which the starting line is composed of a score formed by engraving from the outer surface.

In the easily openable container lid of the present invention,
(1) One end portion of the pair of opening guide lines is directed downward, and on one of the extension lines, the base portion on one side and the other side of the tongue piece is positioned, and the opening portion The opening start line extends upward from the skirt so as to be located along or outside the lower extension line of the guide line;
Alternatively, (2) the pair of opening guide lines extend through the skirt so as to intersect the axial extension line of the side surface of the tongue piece at two points, respectively, and cross the opening guide lines, An opening start line or an extension of the opening start line extends upward from the skirt portion;
It is possible to adopt such a mode.

  In the easy-open container lid of the present invention, the opening line torn by pulling up the pull ring extends a curved portion that is a boundary portion between the top plate portion and the skirt portion of the metal lid shell body, respectively. The function is separated into a guide wire and a pair of opening start lines extending from the lower end of the skirt portion of the metal lid shell (both base portions of the tongue pieces). In order to remove the container lid fixed to the container mouth from the container mouth and open the container mouth, it is only necessary to pull up the pull ring. By this pulling up, first the lower end of the skirt at the base of the tongue piece A pair of opening start lines extending from the opening is torn, and the opening guide line is torn continuously with the tearing of the opening starting line, whereby the container lid can be easily removed from the container mouth.

  In the present invention, in the opening start line and the opening guide line separated as described above, the opening guide line does not extend to the lower part of the skirt part, and the opening start line is a boundary part between the skirt part and the top plate part. Constructed not to extend in the circumferential direction of the curved part, at the same time, forming the opening guide line by engraving from the inner surface of the metal lid shell, and forming the opening opening line by engraving from the outer surface of the metal shell It has a remarkable feature in the point. By forming a pair of opening guide lines and a pair of opening start lines in this manner, it is possible to effectively damage the portion where the opening line is formed when a metal lid shell is formed by punching and drawing or bending. Can be prevented.

  That is, when a metal plate on a flat plate on which an opening line for tearing is formed is punched and subsequently subjected to drawing or bending, the upper surface of the curved portion serving as a boundary portion between the top plate portion and the skirt portion is A radial stress that causes the metal plate to stretch is generated, and a radial stress that causes the metal plate (lid shell) to contract is generated on the lower surface of the curved portion. Accordingly, if an opening line extending in the circumferential direction through such a curved portion is formed by engraving from the outer surface, the opening line is easily damaged (for example, torn). This is because stress is generated on the side where the opening line is engraved so as to stretch it. However, according to the present invention, since the opening line (that is, the opening guide line) extending in the circumferential direction through the curved portion of the top plate portion and the skirt portion is formed by engraving from the inner surface, the above inconvenience is caused. It can be effectively prevented. That is, the stress generated on the inner surface side acts in the direction in which the metal plate contracts, and does not act in the direction in which the inner surface side on which the opening guide line is engraved is stretched. The portion where the opening guide line is formed is not damaged by the stress generated during processing. The opening line extending upward from the lower end of the skirt portion (the base of the tongue piece), that is, the opening start line is formed by engraving from the outer surface. Does not extend at least in the circumferential direction of the curved portion, which is the boundary between the top plate portion and the skirt portion, and this portion is damaged by the stress acting in the radial direction generated during drawing or bending of the curved portion. No problem arises.

Further, when the skirt part is drawn or bent beyond the curved part, the bent part protrudes inward from the vertical part and the horizontal part extending outwardly as the metal is processed from the flat state to the vertical state. Are formed, and the bent portion gradually moves downward to form a vertically extending skirt portion.
Therefore, when the skirt portion is formed by such bending, stress is generated on the lower surface side of the skirt portion so as to extend the boundary portion (that is, the bent portion) between the vertical portion and the horizontal portion. In addition, a stress that causes the boundary portion to contract is generated on the upper surface side. In particular, the greatest stress is generated at the lower end. Therefore, if the opening start line extending from the lower end of the skirt part (the base part of the tongue piece) is formed by engraving from the lower surface in the same manner as the opening guide line described above, the opening starts due to the stress generated on the lower surface. The line will be torn and damaged. However, in the present invention, since the opening start line extending from the lower end of the skirt portion (the base portion of the tongue piece) is formed by engraving from the outer surface, it is disadvantageous that it is torn and damaged by the above stress. It can be effectively prevented. In addition, since the end portion of the opening side of the opening guide line formed by engraving from the inner surface does not extend to the lower part of the skirt, the opening guide line is torn and damaged by the stress described above. There is no risk of doing so.

  As described above, according to the present invention, when the opening guide line to be torn by pulling up the pull ring and the opening start line are structured as described above, the metal lid shell is formed by drawing or bending. It is possible to effectively prevent breakage of the opening line. For example, if the unsealing line is entirely formed by engraving from the inner surface as in Patent Document 1, the opening line is likely to be damaged in the vicinity of the lower end of the skirt portion.

It is a partially broken perspective view of the easily openable container lid of this invention. It is a top view of the easy-open container lid of FIG. It is a side view of the easy-open container lid of FIG. It is a sectional side view (AA sectional view of FIG. 2) of the easy-open container lid of FIG. It is a sectional side view which shows the principal part of the state before putting the easy-open container lid of FIG. 1 on a container opening | mouth part, and winding up. It is a sectional side view which shows the principal part of the state after covering the container opening part of FIG. It is a figure which expands and shows the BB cross section of the easy-open container lid of FIG. It is a figure which shows a state when opening the easily openable container lid | cover of FIG. 1 fastened and fixed to the container opening part. It is a figure which expands and shows the skirt part in CC cross section of the easy-open container lid of FIG. It is a figure which shows the process of the punching at the time of shape | molding the metal lid | cover of the easily openable container lid | cover of FIG. It is a figure which expands and shows the principal part of the process (c) of the process of FIG. It is a figure which shows the pattern different from FIG. 1 of the positional relationship of the opening guide line and opening start line in the easy-open container lid of this invention.

  Referring to FIGS. 1 to 5, the easy-open container lid of the present invention according to this aspect includes a metal lid shell 1, a resin pull ring 3, and a liner material 5 indicated as a whole. .

  The metal lid shell 1 includes a top plate portion 7, a skirt portion 9 connected to the top plate portion 7, and a tongue piece 11 protruding downward from the lower end of the skirt portion 9. The boundary portion with the portion 9 is a curved portion 13 because the inner surface thereof is a portion in close contact with the corner portion at the upper end of the container mouth portion. Further, as is apparent from FIG. 4, the tongue piece 11 is attached with the resin pull ring 3, and therefore the lower portion thereof has a shape inclined outwardly downward.

  The metal lid shell body 1 having the above-described shape is formed by punching a metal plate into a predetermined shape and forming by drawing or bending described later. As the metal material, surface untreated steel (black plate), surface Light metals such as treated steel and aluminum are used. As surface-treated steel, chemical treatment such as phosphoric acid treatment and chromic acid treatment; chemical treatment such as electrolytic chromic acid treatment; electrolytic plating treatment such as electrolytic tin plating, electrolytic zinc plating and electrolytic chrome plating; Examples thereof include a plating treatment; a hot dipping treatment such as a hot tin plating treatment. Among these, aluminum or an aluminum alloy is preferable in terms of easy opening, and the thickness thereof is generally in the range of 0.15 to 0.25 mm.

  In addition, at least the surface which becomes the lid inner surface of the metal plate used for drawing or bending is painted with a protective paint. Suitable examples of paints are thermosetting resin paints such as phenol-formaldehyde resins, furan-formaldehyde resins, xylene-formaldehyde resins, ketone-formaldehyde resins, urea formaldehyde resins, melamine-formaldehyde resins, alkyd resins, unsaturated polyester resins. , Epoxy resin, bismaleimide resin, triallyl cyanurate resin, thermosetting acrylic resin, silicone resin, oil-based resin, or thermoplastic resin paint such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer Partially saponified products, vinyl chloride-maleic acid copolymers, vinyl chloride-maleic acid-vinyl acetate copolymers, acrylic polymers, saturated polyester resins, and the like. These fat paints may be used alone or in combination of two or more.

  The resin pull ring 3 is formed such that the lower end portion of the tongue piece 11 is embedded therein. By pulling up the resin pull ring 3, the metal lid shell 1 is torn, and the easy-open container lid (metal lid shell 1) fixed to the container mouth is removed from the container mouth. Can be opened.

  Such a resin pull ring 3 is provided with a protruding portion 15 on the upper surface thereof, and the tongue piece 11 is bent at the time of opening, and the pull ring 3 is prevented from being torn off at this portion. Further, the outwardly extending protrusions 17 provided on both sides of the pull ring 3 prevent a finger from slipping and hitting a broken end of an opening start line (described later).

  Further, since the resin pull ring 3 is to be pulled up by inserting a finger into the ring, the resin pull ring 3 has a slightly curved shape so that the pulling-up operation can be easily performed (particularly, refer to FIG. 4). . Further, the shape of the resin pull ring 3 may be arbitrary as long as the fingertip can be easily inserted. For example, it can take any shape such as a circle, an ellipse, an ellipse, a rectangle with rounded corners, etc., and its thickness or width is generally in the range of about 1.0 to 3.0 mm.

The resin material for forming the resin pull ring 3 is not particularly limited as long as it can be molded and can secure an appropriate strength, but is generally preferably high-density polyethylene or isotactic polypropylene, particularly preferably. Is a high density polyethylene having a density of 0.935 to 0.965 g / cm ³ and a melt flow rate of 0.1 to 20 g / 10 min. The resin material may contain a small amount of a colorant, a lubricant or a release agent.

  In general, the resin pull ring 3 is molded separately from the metal lid shell 1 and fixed to the tongue 11 by heat fusion, or the metal lid shell 1 is accommodated in a mold. It is formed by insert molding or the like. When the resin pull ring 3 is formed by insert molding, by forming one or a plurality of holes in the lower part of the tongue piece 11, the resin on the upper surface side and lower surface side of the tongue piece 11 is integrated, The joint strength between the tongue piece 11 and the resin pull ring 3 can be further improved.

  The liner material 5 is provided on the inner surface of the top plate portion 7 of the metal lid shell 1 and is joined so as not to drop off from the metal lid shell 1. The liner material 5 is made of an organic polymer such as a resin or an elastomer that can be lined and has cushioning properties and sealing performance. A suitable liner material 5 may be a soft resin such as low density polyethylene or an elastomer, and this resin is applied in a molten state and is press-molded to form a liner shape. Of course, a soft vinyl chloride resin or a urethane resin can also be used as the liner. In this case, it is rotated in the form of plastisol and applied to the inside of the metal lid shell 1 (inner surface of the top plate portion 7), and then heated and gelled to form a liner.

  It should be noted that the peripheral edge 5a of the liner material 5, that is, the portion that comes into close contact with the upper end surface of the container mouth when the container lid is fastened to the container mouth is formed thick and pressed from above. Therefore, a concave portion 5b is formed in the peripheral edge portion 5a so as to closely adhere to the container mouth portion.

  The easy-open container lid having the above-described structure is put on the container mouth 60 as shown in FIG. 5, and then the container is opened using a predetermined jig as shown in FIG. It pushes into the mouth part 60 and crimps along the outer surface of the container mouth part 60, whereby the lower end of the skirt part 9 is firmly engaged with the lower side of the outer surface of the protrusion 61 at the upper end of the container mouth part 60. As a result, the metal lid shell 1 is firmly fixed to the container mouth portion 60, and the peripheral edge portion 5a of the liner material 5 is crushed so as to be in close contact with the upper end surface of the container mouth portion 60, thereby providing a good seal. Will be secured.

  In the easily openable container lid having the above-described structure, an opening line that is torn when the pull ring 3 is pulled up is provided in the metal lid shell body 1. The opening guide lines 21 and 21 and a pair of opening start lines 23 and 23 are formed. First, the opening start line 23 is torn, and the tearing guide line 21 is torn following the tearing. The lid shell 1) is removed from the container mouth.

  Please refer to FIGS. 1, 2, and 3 together with FIGS. 7 and 8, which are enlarged cross-sectional views of the main parts in which the forms of the opening guide line 21 and the opening start line 23 are shown.

  The pair of opening guide wires 21 and 21 are formed by engraving from the inner surface side (see particularly FIG. 7), and the top plate portion 7 and the skirt portion 9 are sandwiched between the central portions of the top plate portion 7. It extends through the curved portion 13 at the boundary, one end portion 21a of the boundary portion is directed downward and enters the skirt portion 9, and the base portion of the tongue piece 11 is positioned on the extended line. Yes. That is, the opening guide line 21 does not extend to the lower part of the skirt portion 9 and is torn after the opening start line 23 is torn.

  On the other hand, the pair of opening start lines 23 is formed by engraving from the outer surface side, contrary to the above-described opening guide line 21 (see particularly FIG. 8), and is torn by pulling up the pull ring 3. Therefore, as shown in FIG. 1 and the like, notches 25 and 25 are provided at the base portion of the tongue piece 11 (the connecting portion with the skirt portion 9), which is the tearing start point of the opening start line 23. Thus, the tearing of the opening start line 23 by pulling up the pull ring 3 is easily started. Further, since the opening guide line 21 is torn through the tearing of the opening start line 23, the opening start line 23 is transmitted to the opening guide line 21 smoothly. As shown, the skirt portion 9 extends upward from the base portion of the tongue piece 11 so as to overlap with the extension line of the one end portion 21a of the opening guide line 21, and the end portion 23a of the opening start line 23 is further extended. Has not reached the bending portion 13 (see FIGS. 3 and 8), but may reach the bending portion 13 in some cases. Even in this case, there is no problem if the opening start line 23 does not extend to a position extending in the circumferential direction. The pair of opening guide lines 21 and 21 reach the bending portion 13 from above the skirt portion of the tongue piece 11, extend upward in a direction away from the bending portion 13, extend the bending portion 13 along the circumferential direction, It extends downward from the curved portion 13 opposite to the piece 11 and stops. In order to avoid the possibility that the opening guide line 21 is broken, only the portion extending along the circumferential direction may be provided from the inner surface side. However, the opening guide line 21 is smoothly broken from the opening guide line 21. For this purpose, it is preferable that the opening guide line 21 extends upward from the upper part of the skirt part 9 or the curved part 13.

  As can be understood from the above description, by pulling up the pull ring 3 of the container lid that is crimped and fixed to the container mouth portion 60, as shown in FIG. The opening start lines 23, 23 extending from both ends are torn, whereby the skirt portion 9 a between the opening start lines 23, 23 is rolled up integrally with the tongue piece 11, and the opening start lines 23, 23 are further lifted. When the opening guide lines 21 and 21 are torn from the tearing of the wire, and the pull ring 3 is further pulled up, the tearing of the opening guide lines 21 and 21 proceeds, and the liner positioned between the opening guide lines 21 and 21 Since the material 5 is bonded to the metal lid shell 1, both are rolled up together. Therefore, it is possible to completely remove the container lid (metal lid shell 1) from the container mouth 60 when the unsealed lines 21 and 21 are torn to some extent.

  In the present invention, the unsealing line to be torn by pulling up the pull ring 3 is formed by the unsealing guide lines 21 and 21 formed by engraving from the inner surface side and not extending to the lower part of the skirt portion 9, By forming from the opening start lines 23 and 23 formed by the installation, breakage of the opening line portion when the metal lid shell 1 is formed by punching, drawing or bending can be effectively prevented.

  As already described, the metal lid shell 1 is formed by punching a metal plate and then drawing or bending, and a cutter or the like is used in advance for the metal plate subjected to such processing. Opening lines (opening guide line 21 and opening start line 23) are formed by the engraving. That is, since the portion where the opening line is formed has a thin score, the breakage of the portion where the opening line is formed becomes a problem when the metal plate is formed.

  Referring to FIG. 10 showing the process of punching, drawing or bending such a metal plate, particularly FIG. 10A, a forming apparatus for performing this processing is arranged on a base 80 and above the base. And a punch cutter 81 that can move up and down. On the base 80, the metal plate 83 to be formed (the above-described opening line, that is, the opening guide line 21 and the opening start line 23 are already formed at predetermined positions. The punch cutter 81 has a cylindrical shape whose lower part has an outer diameter corresponding to the shape in which the metal lid 1 is developed, and the outer periphery of the lower end thereof is sharp. It is a sloping surface.

  The base 80 includes a die center 85 in the center, and a die cutter 87 is disposed around the die center 85, and both of them are fixed in position. Moreover, the outer periphery (corner part) of the upper end part of the die center 85 becomes a curvature surface corresponding to the curvature part 13 which is a boundary part between the top plate part 7 and the skirt part 9 in the metal lid shell 1 to be formed. Yes.

  A die ring 89 and a pressure ring 90 are provided in a space between the die center 85 and the die cutter 87, and the die ring 89 is disposed so as to be sandwiched between the pressure ring 90 and the die center 85. Has been. Further, the pressure ring 90 is provided so as to move up and down at a constant width, and the die ring 89 can move up and down together with the pressure ring 90 while being in close contact with the side surface of the die center 85. Furthermore, the upper surface of the die ring 90 is an inclined surface corresponding to the tongue piece 11. In addition, the pressure ring 90 prevents wrinkles at the lower end of the skirt portion 9 by providing a tip surface having an inclination angle gentler than the inclination angle of the inclined surface at the tip of the die ring 89.

When the punch cutter 81 is lowered with the metal plate 83 disposed on the base 80 as described above, and the lower end of the punch cutter 81 enters the space between the die center 85 and the die cutter 87 and descends, As shown in FIG. 10B, the metal plate 83 is cut into a developed shape of the metal lid shell 1.
Further, as the punch cutter 81 is lowered, the pressure ring 90 is lowered, and the die ring is also lowered integrally with the lowering of the pressure ring 90. In this process, the peripheral portion of the cut metal plate 83 is a die center. The curved portion 13 which is the boundary portion between the top plate portion 7 and the skirt portion 9 is formed, and the portions corresponding to the skirt portion 9 and the tongue piece 11 are formed. It will be bent.

  When the punch cutter 81 is subsequently lowered, the peripheral portion of the cut metal plate 83 is squeezed along the side surface of the die center 85 as shown in FIG. As a result, the skirt portion 9 is formed.

  Further, when the punch cutter 81 is lowered and the punch cutter 81 is lowered to the position shown in FIG. 10D, the tongue piece 11 is formed, and thus the top plate portion 7, the curved portion 13, the skirt portion 9 and the tongue piece 11 are formed. The metal lid shell body 1 made of is formed.

  As can be understood from the stamping, drawing or bending forming process, the metal plate on which the opening line is formed in this process is bent at the corresponding portions in the forming process of the curved portion 13 and the skirt portion 9. Therefore, bending stress is generated. For example, as shown in FIG. 11 in which the process of FIG. 10C is partially enlarged, in the portion facing the corner portion 85a of the die center 85 for forming the curved portion 13, the outer surface side is A bending stress is generated in the metal plate 83 so as to expand and the inner surface side contracts. Further, in the boundary portion between the punch cutter 81, the die ring 89, and the die center 85 for forming the skirt portion 9, a bending stress is generated so that the outer surface contracts and the inner surface expands, contrary to the above. It will be. In particular, in the vicinity of the lower end of the skirt portion, the compressive force for squeezing the skirt portion 9 becomes high, and this bending stress becomes significant.

  Accordingly, when the opening line formed in the portion corresponding to the curved portion 13 is formed by engraving from the outer surface side, the opening line is widened by the bending stress generated in the extending direction on the outer surface side. It will be easy to produce damage, such as tearing. In addition, when the opening line extending from the lower end of the skirt part is formed by engraving from the inner surface side, the opening line is expanded by the bending stress generated in the extending direction on the inner surface side, It will be understood that breakage such as tearing is likely to occur.

  However, according to the present invention, the opening line formed in the metal shell 1 extends upward from the opening guide line 21 extending through the curved portion 13 and the base portion of the tongue piece 11 (the lower end of the skirt portion 9). The opening guide line 21 that is functionally separated from the opening start line 23 and extends through the curved portion 13 is formed by engraving from the inner surface side. At the same time, the opening guide line 21 does not extend to the lower part of the skirt portion 9. On the other hand, it is preferable that the opening start line 23 extending from the lower end of the skirt portion is formed by engraving from the outer surface side, and at the same time, the opening start line 23 is formed so as not to extend to the curved portion 13. The curved portion 13 may be reached slightly. Therefore, in the molding process described above, the bending stress generated at the portion facing the corner portion 85a of the die center 85 and at the boundary portion between the die ring 89 and the die center 85 is applied to either the opening guide line 21 or the opening start line 23. On the other hand, there is nothing acting in the direction of contraction and in the direction of extension, and as a result, breakage of the opening line (opening guide line 21 and opening start line 23) when the metal lid shell 1 is formed. This can be effectively prevented.

  In the present invention described above, the opening guide line 21 and the opening start line 23 need to be provided in such a positional relationship that tearing of the opening start line 23 is continuous with tearing of the opening guide line 21. For this reason, in the above-described example, as shown in FIGS. 3 and 8, the opening start line 23 is formed along the extension line so as to overlap the extension line of the opening guide line 21, and The end 23a of the opening start line 23 slightly enters the lower side of the opening guide line 21.

  Of course, the positional relationship between the opening guide line 21 and the opening start line 23 can be a pattern other than the above, and FIG. 12 shows an example of another pattern.

That is, in the example of FIG. 12A, the opening start line 23 is formed so as to intersect with the opening guide line 21.
In the example of FIG. 12B, the end portions 21 a of the pair of opening guide lines 21 are in a positional relationship such that they are located in a region between the pair of opening start lines 23. In this case, since the tearing stress of the pair of opening start lines 23 is directed to the center side of the starting lines 23, 23, the end 21 a of the opening guide line 21 should be present in the region between the opening start lines 23, 23. Thus, the tearing of the opening start line 23 is transmitted to the opening guide line 21 without derailing.

  Further, in the above-described example, the resin ring is used as the pull ring 3. However, the pull ring 3 may be made of metal. When the metal pull ring 3 is provided integrally with the metal lid shell 1, the pull ring forming portion may be punched out before the molding shown in FIG. 10, and the metal pull ring 3 is made of the metal lid. When it is provided separately from the shell 1, it is preferable to curl the portion of the pull ring 3 using an appropriate jig. This is because if the curling process is not performed, inconvenience such as hand cutting may occur when the pull ring 3 is pulled.

  The easy-open container lid of the present invention described above is suitably applied to sealing the mouth of containers such as glass bottles and PET bottles.

1: Metal lid shell 3: Pull ring 5: Liner material 7: Top plate part 9: Skirt part 11: Tongue piece 13: Curved part 21: Opening guide line 23: Opening start line

Claims (3)

A metal lid shell comprising a top plate portion, a skirt portion connected to the top plate portion, and a tongue piece provided on a part of the skirt portion so as to protrude from the edge thereof; extending from the lower end portion of the tongue piece An easily openable lid comprising: a pull ring; and a liner material fixed to an inner surface of a top plate portion of the metal lid shell.
A pair of opening guide lines composed of scores formed by engraving from the inner surface are provided around the curved portion, which is the boundary between the top plate portion and the skirt portion of the metal lid shell body, with the top plate portion interposed therebetween. And the end of the pair of opening guide lines on the tongue piece side is located at least above the lower part of the skirt portion, and
From the bases of the tongue pieces, there are provided unsealing start lines that extend upward from the skirt portion toward the curved portion, but do not extend at least in the circumferential direction of the curved portion, The easy-opening lid, wherein the opening start line is composed of a score formed by engraving from the outer surface.   The ends on one side of the pair of opening guide lines are directed downward, and the bases on one side and the other side of the tongue piece are positioned on the extended line, and the opening guide lines The easy-open lid according to claim 1, wherein the opening start line extends upward from the skirt portion so as to be located along a lower extension line or outside the extension line.   Each of the pair of opening guide lines extends from the opening start line so that the skirt portion extends at two points with the axial extension line of the side surface of the tongue piece and intersects with the opening guide line. The easy-open lid according to claim 1, wherein an extension line of the opening start line extends upward from the skirt portion.

Images