JP5335846B2 - Pilfer proof cap, pilfer proof cap molding apparatus, and method for manufacturing pilfer proof cap - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pilfer-proof cap which generates no breakage of a bridge part at forming an easy-breakage section, and to provide a molding device for a pilfer-proof cap. <P>SOLUTION: In the pilfer-proof cap 10, a recessed section 17c is formed on a slit section 17 of the cap 10 in a thickness direction of a peripheral wall section 12, and the recessed section 17c is surrounded by a pair of long sides 17a, 17a extended in a peripheral direction of the peripheral wall section 12, and a pair of short sides 17b, 17b extended in an axis direction of the peripheral wall section 12. A bottom wall surface 17e and the short side 17b of the recessed section 17c are connected together with a side wall surface 17h in the axial direction inclined from an open side to the bottom wall surface 17e of the recessed section 17c. When a curvature radius R1 of a base end section 17g wherein the bottom wall surface 17e and the side wall surface 17h in the axial direction are met together is set up to be 0.1-0.5 mm, the base end section 17g and the peripheral wall section 12 connected with the long side 17a on an open end side are connected with a concave curved surface having a curvature radius R2 of 0.1-0.8 mm. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

The present invention relates to a beverage container such as a bottle can, a plastic bottle, a glass bottle, etc., and an upper cap body that is fitted to a thread formed in the mouth of the container, and a lower cap body that is locked to the mouth of the container The present invention relates to a cap having a pill fur proof function, and a cap molding apparatus , and a method for manufacturing a pill fur proof cap .

For example, as a cap for a bottle can used as a beverage container, it is locked to an upper part of a cap fitted to a screw thread formed in a bottle can base and a bulge formed in a bottle can base. The cap lower part has a pilfer proof function connected by a breakable part composed of a plurality of slits formed at intervals in the circumferential direction of the cap and a plurality of bridges positioned between the slits. Things are widely used.
When molding such a cap, a cap material formed of a cup of aluminum or an aluminum alloy sheet is formed on an outer tool having a plurality of cutting blade portions formed at intervals in the circumferential direction and an inner surface of the cap material. A molding method and a molding apparatus are known in which a plurality of slits and a plurality of bridges are formed by sandwiching with a fitted inner tool and rolling the cap material along an outer tool (for example, a patent) Reference 1).

  The cap 100 described in Patent Document 1 is formed of, for example, an aluminum alloy or the like. As shown in FIG. 5A, the top plate portion 11 and a peripheral wall substantially hanging from the peripheral portion of the top plate portion 11. And a liner 24 disposed inside the top plate 11.

  A plurality of recesses that are recessed radially inward are formed in the peripheral wall portion 12 at intervals in the circumferential direction, and a knurled portion 13 that constitutes the upper end portion of the peripheral wall portion 12, A groove 14 continuously provided at the lower end (open end side of the peripheral wall portion 12) and having a smaller diameter than the knurled portion 13, a smooth surface having a diameter larger than that of the groove 14 and continuous with the lower end of the groove 14; The female thread formation scheduled portion 15, the upper bead 16 that is connected to the lower end of the female screw formation planned portion 15, and bulges outward in the radial direction, is connected to the lower end of the upper bead 16 and extends in the circumferential direction. A plurality of easily breakable portions 119 each having a slit portion 117 formed in the circumferential direction via the bridge portion 118; a lower bead 20 continuously provided at the lower end of the easily breakable portion 119 and bulging radially outward; The lower bead 20 is connected to the lower end, and the peripheral wall A skirt portion 21 which is a smooth surface forming the open end of the 12 is formed.

The easy-to-break part 119 will be described with reference to FIG. 5 (b) which is an enlarged view of the P part in FIG. 5 (a). The slit part 117 is recessed in the thickness direction of the peripheral wall part 12. A substantially rectangular recess 117c is provided, and the recess 117c includes a pair of long sides 117a and 117a extending in the circumferential direction and a pair of short sides 117b and 117b extending in the axial direction. It is surrounded.
The slit 117 is formed with a notch 117d penetrating in the thickness direction of the peripheral wall portion 12 along the long side 117a located on the top plate portion 11 side.
The bottom wall surface 117e of the recess 117c and the bridge portion 118 are connected to each other by an axial side wall surface 117h inclined from the opening side of the recess 117c toward the bottom wall surface 117e, and the bottom wall surface 117e and the peripheral wall portion 12 are connected. The long side 117a located on the open end side is connected by a circumferential side wall surface 117f inclined from the opening side of the recess 117c toward the bottom wall surface 117e.
The bottom wall surface 117e and the axial side wall surface 117h intersect at the base end portion 117g.

FIGS. 6 and 7 are views showing the state of the cross section taken along the line AA and the cross section taken along the line BB in FIG. 5B, respectively, together with the molding device 130. The molding device 130 includes the outer tool 140. And an inner tool 60.
The outer tool 140 includes at least a bead plate 140p, an outer slit plate 140r, and a skirt plate 140s. The inner tool 60 includes at least an inner bead ring 60p, an inner slit ring 60r, and an inner lower bead ring 60s. (See FIG. 7).

As shown in FIG. 6 in which the bridge portion 118 is cut along the circumferential direction, the outer tool 140 includes a plurality of cutting blade portions 140b extending in the circumferential direction at intervals and having a substantially rectangular shape. Yes.
The outer tool 140 includes a bridge housing portion 140a that is disposed between the cutting blade portions 140b and for housing the bridge portion 118 in a non-contact manner during molding.
The bridge accommodating portion 140a includes bridge accommodating portion inclined wall surfaces 140c and 140c that are inclined so as to approach each other from the ridge line extending in the axial direction of the cutting edge portion 140b toward the outside of the peripheral wall portion 12, and the bridge accommodating portion. It is formed by the bridge accommodating part bottom wall surface 140d which connects the terminal inclination wall surface 140c, the terminal of 140c.

  Further, as shown in FIG. 7 cut along the base end portion 117g (B-B line), the outer tool 140 is an outer slit that is substantially orthogonal to the ridge line on the top plate portion side of the cutting blade portion 140b. An upper bead accommodating portion 140f that accommodates the upper bead 16 in a non-contact manner with the upper end surface 140e of the plate 140r as a part, and a lower bead accommodating portion inclined wall surface 140m that is inclined downward from the lower end of the cutting edge portion 140b. A lower bead accommodating portion 140h that accommodates the lower bead 20 in a non-contact manner as a part thereof.

  The inner tool 60 is formed at a position facing each of the upper bead accommodating portion 140f and the lower bead accommodating portion 140h, and includes an upper bead forming convex portion 60c and a lower bead forming convex portion 60d that press the peripheral wall portion 12 from the inner surface side. (See FIG. 7).

  The cap 100 is nipped and pressed by the outer tool 140 and the inner tool 60 while being rolled, whereby the upper bead 16, the breakable portion 119, the lower bead 20, and the like are formed.

JP 7-89562 A

By the way, in the shaping | molding apparatus 130 described in patent document 1, it has the shape where the said cutting-blade part 140b, 140b and bridge | bridging part inclination wall surface 140c, 140c cross | intersect by corner | angular part 140g, 140g. (See FIG. 6).
When the base end portion 117g of the bridge portion 118 is formed by the corner portions 140g and 140g, there is a problem that the base end portion 117g causes a bridge break when the cap 100 is attached to the bottle can.

Moreover, in the shaping | molding apparatus 130 described in patent document 1, the said cutting blade part 140b and the lower bead accommodating part inclination wall surface 140m also have a shape which cross | intersects at the corner | angular part 140k (refer FIG. 7).
For this reason, when the recess 117c is formed by pushing the cutting edge part 140b into the peripheral wall part, when the cap 100 is attached to the bottle can, the bridge is also broken, and the life of the outer tool 140 is also shortened. There was a problem of shortening.

In view of the above problems, the present invention provides a pill fur proof cap, a pill fur proof cap forming apparatus , and a method for manufacturing a pill fur proof cap that do not cause a bridge break when forming an easily breakable portion. Objective.

In order to solve the above-described problems and achieve the above object, a pilfer-proof cap according to claim 1 includes a disc-shaped top plate portion and a cylindrical shape suspended from a peripheral portion of the top plate portion. The cap material including the peripheral wall portion is easily broken by a plurality of slit portions formed at intervals in the circumferential direction of the peripheral wall portion and a plurality of bridge portions positioned between the slit portions. A cap for pilfer proof in which a portion is formed, wherein the slit portion is formed with a recess recessed in the thickness direction of the peripheral wall portion, and the recess is the peripheral wall portion. A pair of circumferential edges extending in the circumferential direction and a pair of axial edges extending in the axial direction of the circumferential wall portion, and the bottom wall surface of the recess and the axial edge An axial direction inclined from the opening side of the recess toward the bottom wall surface Are continuously provided by a wall, said bottom wall and said axial sidewall surfaces and the base end portion which is associated the radius of curvature R1, and 0.1 mm to 0.5 mm, open from the state of being applied to the bottle can An opening torque value, which is a torque value at which one of the plurality of bridge portions first breaks when plugged, is 160 N · cm or less .

  According to the invention described in claim 1, by providing the radius of curvature R1 at the base end portion, there is no sharp edge, and the thickness of the base end portion after molding is locally reduced, so-called thinning is suppressed. obtain.

A cap for a pilfer proof according to claim 2 is provided on a cap member including a disk-shaped top plate portion and a cylindrical peripheral wall portion suspended from the peripheral portion of the top plate portion. A cap for pilfer proof formed with a plurality of slit portions formed at intervals in the circumferential direction and an easily breakable portion composed of a plurality of bridge portions positioned between the slit portions, The slit portion is formed with a recess recessed in the thickness direction of the peripheral wall portion, and the recess includes a pair of peripheral edges extending in the circumferential direction of the peripheral wall portion. The peripheral wall portion is surrounded by a pair of axial end edges extending in the axial direction, and the slit portion penetrates in the peripheral wall portion thickness direction along one circumferential end edge. An incision is formed, the bottom wall surface of the recess and the axial direction The edge is continuously provided by an axial side wall surface inclined toward the bottom wall surface from the opening side of the recess, a base end portion where the bottom wall surface and the axial side wall surface meet, and the like When connecting the peripheral wall portion connected to the circumferential edge with a concave curved surface having a radius of curvature R2 of 0.1 mm to 0.8 mm, and opening the plug from a state where it is attached to the bottle can, The opening torque value, which is the value of the torque at which one of the bridge portions breaks first, is 160 N · cm or less .

  According to the second aspect of the present invention, by providing the curvature radius R2, the amount of indentation in the axial side wall surface is reduced and the molding distortion at the time of molding is reduced, so the distortion applied to the bridge portion is reduced, and the bridge Occurrence of cuts can be prevented.

The cap for pilfer proof according to claim 3 is characterized in that a radius of curvature R1 of a base end where the bottom wall surface and the axial side wall surface meet is 0.1 mm to 0.5 mm. To do.

  According to the third aspect of the present invention, by providing the curvature radius R1 at the base end portion, sharp edges are eliminated, and the thickness of the base end portion after molding is locally reduced, so-called thinning is suppressed. In addition, by providing the radius of curvature R2, the amount of indentation on the side wall surface in the axial direction is reduced, and molding distortion during molding is reduced, so that distortion applied to the bridge portion is reduced and occurrence of bridge breakage is prevented. Can be done.

According to a fourth aspect of the present invention, there is provided a cap for a pilfer proof cap comprising: a disk-shaped top plate portion; and a cap member provided with a cylindrical peripheral wall portion depending from a peripheral portion of the top plate portion. A cap for pilfer proof for forming an easily breakable portion comprising a plurality of slit portions formed at intervals in the circumferential direction of the peripheral wall portion and a plurality of bridge portions positioned between the slit portions. A plurality of forming devices having a substantially rectangular shape extending on the side facing the peripheral wall portion of the outer tool of the forming device at intervals in the circumferential direction so as to form the slit portion. Are formed between the cutting blade portions and a cutout portion for accommodating the bridge portion. The cutout portion is a shaft extending in the axial direction of the cutting blade portion. From the direction ridge line toward the outside of the peripheral wall Is it provided with a pair of inclined walls which are inclined so as to approach each other, the association portion radius of curvature R1 of between the cutting edge and the inclined wall surface, and a 0.1 mm to 0.5 mm, bottle When the cap is opened from the state where it is attached to the can, the opening torque value, which is the torque value at which one of the plurality of the bridge portions is first broken, is 160 N · cm or less. It is a feature.
Furthermore, the manufacturing method of the cap for pilfer proof of Claim 7 is a cap material provided with a disk-shaped top-plate part and the cylindrical surrounding wall part suspended from the peripheral part of this top-plate part. A cap for pilfer proof for forming an easily breakable portion comprising a plurality of slit portions formed at intervals in the circumferential direction of the peripheral wall portion and a plurality of bridge portions positioned between the slit portions. A side of the outer tool of the molding apparatus that faces the peripheral wall portion, and is extended at intervals in the circumferential direction to form the slit portion, and has a plurality of substantially rectangular shapes. A cutting edge part and a notch part for accommodating the bridge part are formed between the cutting edge parts, and the notch part extends in the axial direction of the cutting edge part. From the ridge to the outside of the peripheral wall A pair of inclined wall surfaces that are inclined so as to approach each other, and the radius of curvature R1 of the meeting portion between the cutting edge portion and the inclined wall surface is 0.1 mm to 0.5 mm, and is attached to the bottle can When the plug is opened from the formed state, an opening torque value, which is a torque value at which one of the plurality of formed bridge portions is first broken, is 160 N · cm or less.

According to the invention of claim 4 and the invention of claim 7 , the base end portion is press-molded according to the radius of curvature R1 of the meeting portion of the cutting edge portion and the notch portion, so that there is no sharp edge, It is possible to suppress the occurrence of so-called thinning in which the plate thickness of the base end portion after forming is locally reduced.

Further, the apparatus for forming a cap for a pilfer proof according to claim 5 includes a cap member provided with a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from a peripheral portion of the top plate portion. A cap for pilfer proof for forming an easily breakable portion comprising a plurality of slit portions formed at intervals in the circumferential direction of the peripheral wall portion and a plurality of bridge portions positioned between the slit portions. A plurality of forming devices having a substantially rectangular shape extending on the side facing the peripheral wall portion of the outer tool of the forming device at intervals in the circumferential direction so as to form the slit portion. A cutting edge portion and a cutout portion that is disposed between the cutting edge portions and accommodates the bridge portion, and is formed of a circumferential ridge line extending in the circumferential direction of the cutting edge portion. On the side, the thickness of the peripheral wall to the slit Cuts penetrating is formed, the curvature radius R2 of at least near both ends of the other circumferential ridge extending in the circumferential direction of the cutting edge, has a 0.1Mm～0.8Mm, the bottle can When the plug is opened from the worn state, an opening torque value, which is a torque value at which one of the plurality of formed bridge portions first breaks, is 160 N · cm or less. Is.
Furthermore, the manufacturing method of the cap for pilfer proof of Claim 8 is a cap material provided with a disk-shaped top-plate part and the cylindrical surrounding wall part suspended from the peripheral part of this top-plate part. A cap for pilfer proof for forming an easily breakable portion comprising a plurality of slit portions formed at intervals in the circumferential direction of the peripheral wall portion and a plurality of bridge portions positioned between the slit portions. A side of the outer tool of the molding apparatus that faces the peripheral wall portion, and is extended at intervals in the circumferential direction to form the slit portion, and has a plurality of substantially rectangular shapes. A side of one circumferential ridge line that is formed between the cutting edge part and the notch part that is arranged between the cutting edge parts and accommodates the bridge part and extends in the circumferential direction of the cutting edge part In the slit wall, the peripheral wall thickness direction A through-cut was formed, and the radius of curvature R2 in the vicinity of at least both ends of the other circumferential ridge line extending in the circumferential direction of the cutting edge portion was 0.1 mm to 0.8 mm, and was attached to the bottle can. When the plug is opened from the state, an opening torque value, which is a torque value at which one of the plurality of formed bridge portions breaks first, is 160 N · cm or less.

According to the invention described in claim 5 and the invention described in claim 8 , the axial side wall surface is press-molded in accordance with the curvature radius R2 of the other circumferential ridge line. Since the molding distortion is reduced and the molding distortion at the time of molding is reduced, the distortion applied to the bridge portion is reduced, and the occurrence of bridge breakage can be prevented.
In addition, by reducing the amount of pressing on the axial side wall surface, the stress applied to the outer tool is reduced, and the life of the outer tool is increased.

Further, the apparatus for forming a cap for pilfer proof according to claim 6 includes: a cap member including a disk-shaped top plate portion and a cylindrical peripheral wall portion suspended from the peripheral edge portion of the top plate portion. A cap for pilfer proof for forming an easily breakable portion comprising a plurality of slit portions formed at intervals in the circumferential direction of the peripheral wall portion and a plurality of bridge portions positioned between the slit portions. A plurality of forming devices having a substantially rectangular shape extending on the side facing the peripheral wall portion of the outer tool of the forming device at intervals in the circumferential direction so as to form the slit portion. Are formed between the cutting blade portions and a cutout portion for accommodating the bridge portion. The cutout portion is a shaft extending in the axial direction of the cutting blade portion. From the direction ridge line toward the outside of the peripheral wall A pair of inclined wall surfaces that are inclined so as to approach each other, and a radius of curvature R1 of a meeting portion between the cutting edge portion and the inclined wall surface is set to 0.1 mm to 0.5 mm, and On the side of one circumferential ridge line extending in the circumferential direction of the blade portion, a slit that penetrates in the circumferential wall portion thickness direction is formed in the slit portion, and the other circumference extending in the circumferential direction of the cutting blade portion The radius of curvature R2 near at least both ends of the directional ridge line is set to 0.1 mm to 0.8 mm, and when the cap is opened from the state of being attached to the bottle can, The opening torque value, which is the torque value at which one breaks first, is 160 N · cm or less .
Furthermore, the manufacturing method of the cap for pilfer proof of Claim 9 is a cap material provided with a disk-shaped top plate part, and the cylindrical surrounding wall part suspended from the peripheral part of this top plate part. A cap for pilfer proof for forming an easily breakable portion comprising a plurality of slit portions formed at intervals in the circumferential direction of the peripheral wall portion and a plurality of bridge portions positioned between the slit portions. A side of the outer tool of the molding apparatus that faces the peripheral wall portion, and is extended at intervals in the circumferential direction to form the slit portion, and has a plurality of substantially rectangular shapes. A cutting edge part and a notch part for accommodating the bridge part are formed between the cutting edge parts, and the notch part extends in the axial direction of the cutting edge part. From the ridge to the outside of the peripheral wall A pair of inclined wall surfaces that are inclined so as to approach each other, and a radius of curvature R1 of a meeting portion between the cutting blade portion and the inclined wall surface is set to 0.1 mm to 0.5 mm, and the cutting blade The other circumferential direction in which the slit which penetrates in the peripheral wall part thickness direction is formed in the slit part on the side of one circumferential ridge line extending in the circumferential direction of the part and extends in the circumferential direction of the cutting edge part The curvature radius R2 in the vicinity of at least both ends of the ridge line is set to 0.1 mm to 0.8 mm, and one of the plurality of the bridge portions formed when the cap is opened from the state of being attached to the bottle can The opening torque value, which is the value of the torque to break, is 160 N · cm or less.

According to the invention described in claim 6 and the invention described in claim 9 , the base end portion is press-molded according to the curvature radius R1 of the meeting portion of the cutting edge portion and the notch portion, so that there is no sharp edge. The thickness of the base end portion after molding can be locally reduced, so-called thinning can be suppressed, and the axial side wall surface is press molded in accordance with the curvature radius R2 of the other circumferential ridge line. Therefore, the amount of indentation on the side wall surface in the axial direction is reduced, and the molding distortion at the time of molding is reduced. Therefore, the distortion applied to the bridge portion is reduced, and the occurrence of bridge breakage can be prevented.
In addition, by reducing the amount of pressing on the axial side wall surface, the stress applied to the outer tool is reduced, and the life of the outer tool is increased.

According to the pill fur proof cap and the pill fur proof cap molding apparatus according to the present invention, the strength of the bridge portion is sufficiently ensured by suppressing the occurrence of thinning at the base end portion when forming the easily breakable portion. It is possible to effectively prevent the bridge from being cut when the cap is attached to the bottle can.
Further, according to the pill fur proof cap and the pill fur proof cap molding apparatus according to the present invention, the twist applied to the bridge portion can be reduced by reducing the pressing amount when forming the easily breakable portion and reducing the molding distortion. This can be reduced, and bridge breakage when the cap is attached to the bottle can can be effectively prevented, and the life of the outer tool can be increased by reducing the stress applied to the outer tool.

In the embodiment of the present invention, (a) is a half sectional view of the cap 10, and (b) is an enlarged view of a Q portion. It is the figure which showed the mode of the CC sectional view of FIG.1 (b) with the shaping | molding apparatus 30. FIG. It is the figure which showed the mode of the DD sectional view of FIG.1 (b) with the shaping | molding apparatus 30. FIG. It is a figure which shows the result of the verification experiment of this invention, Comprising: (a) shows the result of Experiment 1, (b) shows the result of Experiment 2, respectively. It is a figure which shows the conventional cap 100, Comprising: (a) is a half sectional view of the cap 100, (b) is the P section enlarged view. It is the figure which showed the mode of the AA sectional view of FIG.5 (b) with the shaping | molding apparatus 130. FIG. It is the figure which showed the mode of the BB sectional view of FIG.5 (b) with the shaping | molding apparatus 130. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the following, the same components as those in FIGS. 5 to 7 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  The cap 10 of the present embodiment is formed of, for example, an aluminum alloy or the like. As shown in FIG. 1A, the top plate portion 11 and a peripheral wall portion 12 that is substantially suspended from the peripheral edge portion of the top plate portion 11. , And a liner 24 disposed inside the top plate portion 11.

Also in the cap 10 of the present embodiment, the peripheral wall portion 12 has a knurled portion 13, a groove 14, a female screw formation scheduled portion 15, an upper bead 16, and a lower bead 20, as in FIG. The skirt portion 21 is formed, but in this embodiment, the configuration of the easily breakable portion 19 connected to the lower end of the upper bead 16 is different from that of the easily breakable portion 119 in FIGS. ing.
The breakable portion 19 is configured by forming a plurality of slit portions 17 extending in the circumferential direction in the circumferential direction via the bridge portion 18.

The details of the easily breakable portion 19 will be described with reference to FIG. 1B which is an enlarged view of the Q portion in FIG. 1A. The slit portion 17 is recessed in the thickness direction of the peripheral wall portion 12. A recess 17c having a substantially rectangular shape when viewed from the side is provided in the recess. The recess 17c includes a pair of long sides (circumferential edges) 17a and 17a extending in the circumferential direction and a pair extending in the axial direction. Are surrounded by short sides (end edges in the axial direction) 17b and 17b.
The slit portion 17 is formed with a notch 17d penetrating in the thickness direction of the peripheral wall portion 12 along the long side 17a (one circumferential direction edge 17a) located on the top plate portion 11 side. .
The bottom wall surface 17e of the recess 17c and the bridge portion 18 are connected to each other by an axial side wall surface 17h inclined from the opening side of the recess 17c toward the bottom wall surface 17e. The long side 17a located on the open end side is continuously provided by a circumferential side wall surface 17f inclined from the opening side of the recess 17c toward the bottom wall surface 17e.

Here, in the present embodiment, the meeting portion between the bottom wall surface 17e and the axial side wall surface 17h is a base end portion 17g having a curvature radius R1, and the curvature radius R1 is 0.1 mm to 0 mm. .5 mm.
In the present embodiment, the base end portion 17g and the peripheral wall portion 12 connected to the long side 17a (the other peripheral end edge 17a) located on the open end side of the peripheral wall portion 12 are connected with a curvature radius R2. The radius of curvature R2 is 0.1 mm to 0.8 mm.

FIGS. 2 and 3 are views showing the cross section taken along the line C-C and the line D-D as seen in FIG. 1B together with the molding device 30. The molding device 30 includes an outer tool 40. And an inner tool 60.
The outer tool 40 includes at least a bead plate 40p, an outer slit plate 40r, and a skirt plate 40s (see FIG. 3).
The configuration of the inner tool 60 is as described above.

As shown in FIG. 2 in which the bridge portion 18 is cut along the circumferential direction, the outer tool 40 includes a plurality of cutting blade portions 40b extending in the circumferential direction at intervals and having a substantially rectangular shape. The notches 17d are formed on the side of the ridge line on the top plate portion side extending in the circumferential direction of the cutting edge portion 40b.
Moreover, the outer tool 40 is arrange | positioned between the cutting blade parts 40b, and is provided with the bridge | bridging accommodating part 40a for accommodating the bridge | bridging part 18 non-contacting at the time of shaping | molding.
The bridge housing portion 40a includes bridge housing portion inclined wall surfaces 40c and 40c that are inclined so as to approach each other from the ridge line extending in the axial direction of the cutting edge portion 40b toward the outside of the peripheral wall portion 12, and the bridge housing portion. It is formed by the bridge accommodating part bottom wall surface 40d which connects the terminal inclination wall surface 40c, the terminal of 40c.

  Moreover, as shown in FIG. 3 cut along the base end portion 17g (DD line), the outer tool 40 is an outer slit that is substantially orthogonal to the ridge line on the top plate portion side of the cutting blade portion 40b. An upper bead accommodating portion 40f that accommodates the upper bead 16 in a non-contact manner with the upper end surface 40e of the plate 40r as a part thereof, and a lower bead accommodating portion inclined wall surface 40m that is inclined downward from the lower end of the cutting edge portion 40b. A lower bead accommodating portion 40h that accommodates the lower bead 20 in a non-contact manner as a part thereof.

Here, in the present embodiment, associating portions 40g and 40g between the cutting edge portions 40b and 40b and the bridge accommodating portion inclined wall surfaces 40c and 40c have a radius of curvature of 0.1 mm to 0.5 mm, similar to R1. Yes.
Further, of the ridge lines extending in the circumferential direction of the cutting edge portion 40b in the vicinity of both ends of the meeting portion 40k between the cutting edge portion 40b and the lower bead accommodating portion inclined wall surface 40m, the ridge line on the open end side of the peripheral wall portion 12 The vicinity of both ends has a radius of curvature of 0.1 mm to 0.8 mm, similar to R2.

  The reason why the radius of curvature R1 is 0.1 mm to 0.5 mm is that when R1 is smaller than 0.1 mm, the plate thickness t2 at the base end portion 17g is more local than the plate thickness t1 of the peripheral wall portion 12 before molding. However, when the so-called thinning is still remarkable, the strength of the bridge portion 18 is lowered. On the other hand, when R1 is larger than 0.5 mm, the strength of the bridge portion 18 is excessively increased, and the bottle can This is because the opening torque when the attached cap 10 is opened is too high.

  The reason why the radius of curvature R2 is set to 0.1 mm to 0.8 mm is that when R2 is smaller than 0.1 mm, the pushing amount when the axial side wall surface 17h is formed increases. While it becomes impossible to sufficiently reduce the molding distortion at the time of forming, when R2 is larger than 0.8 mm, the strength of the cutting edge portion 40b of the outer tool 40 is insufficient, and the molding of the recess 17c is unstable. Because it becomes.

The operation of the molding apparatus 30 configured as described above will be described.
As shown in FIG. 2 and FIG. 3, when the cap 10 that is rolled by a drive device (not shown) is pressed by the inner tool 60 in the direction of the outer tool 40, the cutting edge portion 40 b of the outer tool 40 becomes a peripheral wall. The part 12 is sheared and penetrated, and the peripheral wall part 12 is formed with a recess 17c and a notch 17d.
The peripheral wall portion 12 is formed by the upper bead 16 and the lower bead 20 bulging outward by being pressed by the upper bead molding convex portion 60c and the lower bead molding convex portion 60d of the inner tool 60.

At this time, the meeting portion 40g between the cutting edge portions 40b and 40b of the outer tool 40 and the bridge accommodating portion inclined wall surfaces 40c and 40c is formed with a radius of curvature R1 of 0.1 mm to 0.5 mm. The base end portion 17g where the bottom wall surface 17e and the axial side wall surface 17h are associated is also pressed by the associated portion 40g and shaped to have a radius of curvature R1.
Therefore, a reduction in the plate thickness before and after molding due to thinning is reduced, and sufficient strength of the bridge portion 18 is ensured.
Further, the vicinity of both ends of the meeting portion 40k between the cutting edge portion 40b of the outer tool 40 and the lower bead accommodating portion inclined wall surface 40m is formed with a radius of curvature R2 of 0.1 mm to 0.8 mm. And the peripheral wall portion 12 connected to the long side 17a (the other circumferential end edge 17a) positioned on the open end side are also formed so as to be connected with a curvature radius R2.

  The cap 10 formed as described above is attached to the bottle can by being plastically deformed along the shape of the bottle can base after being put on a bottle can base not shown. Sometimes when rotated with respect to the bottle can base part, the upper part of the cap 10 rotates while moving upward according to the thread lead formed in the bottle can base part, while the lower part of the cap 10 is the bottle can base part. The cap 10 is separated from the upper and lower portions by only being rotated by being locked by the bulging portion and not moving upward, and the bridge portion 18 is torn off.

Here, in order to verify the effect of the present invention, the following experiment was performed in which the radius of curvature R1 or the radius of curvature R2 was changed when the slit portion was formed in the cap 10 having an outer diameter of 38 mm.
<Experiment 1> 20 samples each having a radius of curvature R2 of 0.5 mm and a radius of curvature R1 of 0.05 mm, 0.1 mm, 0.2 mm, 0.5 mm, and 0.7 mm were prepared, respectively (A ) Thinning amount, (B) Bridge strength, (C) Opening torque, (D) Opening angle, (E) Number of occurrences of bridge breakage under tension limit condition, and (F) Number of occurrences of bridge breakage under compression limit condition Each of them was evaluated.
<Experiment 2> 20 samples each having a radius of curvature R1 of 0.2 mm and a radius of curvature R2 of 0.05 mm, 0.1 mm, 0.5 mm, 0.8 mm, and 1.0 mm were prepared. Each of () bridge strength, (C) opening torque, (D) opening angle, (E) number of occurrences of bridge breakage under tension limit conditions, and (F) number of occurrences of bridge breakage under compression limit conditions were evaluated.

The definition and evaluation method of each evaluation item described above are as follows.
(A) Thinning amount:
After the cap formed with the slit portion is filled with resin, it is cut along the CC section in FIG. 1, and this section is photographed with a microscope.
And the thickness (plate thickness t2 in FIG. 2) of the smallest plate thickness around the base end portion 17g in FIG. 2 is measured, and the plate thickness t1 before molding and the plate thickness t2 The difference (t1-t2) is defined as the thinning amount.
The value of the thinning amount is desirably as small as possible.

(B) Bridge strength:
(1) A plurality of test pieces obtained by cutting out the bridge portions 18 one by one are obtained from the cap 10.
(2) The test piece is directed downward (the open end of the peripheral wall portion 12 is directed upward), and the top plate portion 11 side is fixed to a measuring device (not shown).
(3) Clamp the skirt of the test piece with the grip of the measuring device.
(4) With the clamp state maintained, the gripping part is pulled up at a constant speed, and the load until the bridge part breaks is measured.
(5) For all the test pieces, the above (3) and (4) are repeated, and the breaking load of the test piece that is broken at the smallest load is defined as the bridge strength.
The bridge strength value is desirably 50 [N] or more.

(C) Opening torque:
When the cap 10 attached to the bottle can is opened, the torque value at which one of the plurality of bridge portions 18 breaks first is defined as the opening torque.
The value of the opening torque is desirably 160 [N · cm] or less.

(D) Opening angle:
When the cap 10 attached to the bottle can is opened, the rotation angle of the cap 10 until all the plurality of bridge portions 18 are broken is defined as the opening angle.
The value of the opening angle is desirably 300 degrees or less.

(E) Number of occurrences of bridge breakage under tension limit conditions:
Set the conditions to generate a strong tensile stress on the bridge during capping, and count the number of bridges that break.
The condition settings for the limit test at this time are as follows.
(1) Axial load when drawing at the edge P during capping: 970 [N]
(2) Torque of skirt winding roll when skirt winding is performed on skirt portion 21: 3.8 [Nm]
(3) Distance between the hem winding roll and the die for drawing at the edge P: 14.9 [mm]
(4) Internal pressure: 2.2 [kgf / cm ² ]
In this test, the case where no bridge breakage occurred at all for 20 samples was determined as OK.

(F) Number of bridge breakage under compression limit condition:
Set the condition that a strong compressive stress is generated on the bridge during capping, and count the number of bridges that break.
The condition settings for the limit test at this time are as follows.
(1) Axial load when drawing at the edge P during capping: 950 [N] for the first time and 800 [N] for the second time
(2) Torque of screw roll when female thread machining is performed on the female thread formation scheduled portion 15: 3.8 [Nm] for the first time and 3.0 [Nm] for the second time
(3) Torque of the skirt winding roll when the skirt portion 21 is skirt-wound: 3.8 [Nm] for both the first time and the second time
(4) Distance between screw roll and die for drawing at end edge P: 2.6 [mm] for both first and second time
(5) Distance between the skirt winding roll and the mold for drawing the edge P: 15.9 [mm] for the first time and 15.6 [mm] for the second time
Also in this test, the case where no bridge breakage occurred at all for 20 samples was determined as OK.

The experimental results are shown in FIG.
Here, FIG. 4 (a) shows the results for Experiment 1, and FIG. 4 (b) shows the results for Experiment 2.

In Experiment 1, when the curvature radius R1 is 0.1 mm, 0.2 mm, and 0.5 mm, the thinning amount of the evaluation item (A) is within 0.1 mm, and other evaluation items Desirable results could be obtained for all of (B) to (F).
On the other hand, when the curvature radius R1 was set to 0.05 mm, the evaluation items (B), (E), and (F) could not be satisfied.
This is because, as a result of the thinning amount of the evaluation item (A) being a large value (0.15 mm) compared to the other samples, the bridge strength of the evaluation item (B) is reduced, and the bridge breaks under the limit condition. It is understood that it occurred.

Similarly, in Experiment 1, when the radius of curvature R1 was 0.7 mm, the evaluation items (C) and (D) could not be satisfied. However, this was caused by the bridge strength becoming too high. It is understood that the plug torque has increased.
From the result of the above experiment 1, the validity of setting the range of the curvature radius R1 to 0.1 mm to 0.5 mm could be verified.

Next, in Experiment 2, when the curvature radius R2 was set to 0.1 mm, 0.5 mm, and 0.8 mm, desirable results could be obtained for all the evaluation items (B) to (F).
On the other hand, when the curvature radius R2 was set to 0.05 mm, the evaluation items (B), (E), and (F) could not be satisfied.
This is understood that the curvature radius R2 is too small, the molding distortion at the time of molding the easily breakable portion is increased, the bridge portion is twisted, and the bridge is broken.
Further, when the curvature radius R2 was set to 1.0 mm, the notch 17d was not appropriately drilled due to molding failure, and the sample evaluation could not be performed at all.
This is understood that the curvature radius R2 is too large, the strength of the cutting edge portion of the outer tool is insufficient, and the molding of the easily breakable portion becomes unstable.
From the result of Experiment 2, the validity of setting the radius of curvature R2 to 0.1 mm to 0.8 mm could be verified.

According to the present embodiment, the curvature radius R1 of the meeting portion 40g of the outer blade 40 between the cutting edge portion 40b and the bridge accommodating portion inclined wall surface 40c is set to 0.1 mm to 0.5 mm. The base end portion 17g of the slit portion 17 formed by pressing is also formed with a curvature radius R1 of 0.1 mm to 0.5 mm.
Therefore, compared to the case where the corner portion is pressed, the plate thickness t2 after molding of the base end portion 17g is locally thinner than the plate thickness t1 before molding, so-called thinning can be reduced. Therefore, the strength of the bridge portion 18 can be sufficiently ensured, and bridge breakage when the cap 10 is attached to the bottle can can be effectively prevented.

Further, according to the present embodiment, the curvature radius R2 of the outer tool 40 in the vicinity of both ends of the meeting portion 40k between the cutting edge portion 40b and the lower bead accommodating portion inclined wall surface 40m is set to 0.1 mm to 0.8 mm. When pressed by the meeting portion 40k, the base end portion 17g of the slit portion 17 and the peripheral wall portion 12 connected to the long side 17a located on the open end side are also formed to be connected with a radius of curvature R2. The pushing amount of the outer tool 40 can be reduced.
Therefore, since the molding distortion at the time of molding the axial side wall surface 17h is reduced and the twist applied to the bridge portion 18 can be reduced, the bridge breakage when the cap 10 is attached to the bottle can can be effectively prevented. In addition, the lifetime of the outer tool 40 can be increased by reducing the stress applied to the outer tool 40.

The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist.
Specifically, in the embodiment described above, the dimensional ranges of the curvature radius R1 and the curvature radius R2 are limited, but at least one dimensional range of the curvature radius R1 and the curvature radius R2 is limited. Thus, the required effect described above can be achieved.
Further, in the above-described embodiment, the notch 17d penetrating in the thickness direction of the peripheral wall portion 12 is formed along the long side 17a located on the top plate portion 11 side. However, the notch 17d is formed on the peripheral wall portion. 12 may be formed on the open end side.
Further, in the above-described embodiment, the radius of curvature of the cutting edge portion 40b and the lower bead accommodating portion inclined wall surface 40m in the vicinity of both ends of the meeting portion 40k is R2, and the curvature radius of the meeting portion 40k is R2 may be used over the entire length.

It is possible to provide a pilfer proof cap, a pilfer proof cap molding apparatus , and a method for manufacturing a pilfer proof cap that do not cause breakage of the bridge when forming an easily breakable portion.

10 cap
12 Perimeter wall
17 Slit
17c recess
17d cutting
17e Bottom wall
17h Axial side wall surface
18 Bridge section
19 Easy break
40 Outer tool
40a Bridge housing
40c Inclined wall of bridge housing part
40d Bridge housing bottom wall
40g, 40k meeting section
40m lower bead housing part sloping wall
60 Outer tool
R1, R2 radius of curvature

Claims (9)

A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a pilfer proof cap in which an easy-to-break portion composed of a plurality of bridge portions positioned between the slit portions is formed,
The slit portion is formed with a recess recessed in the thickness direction of the peripheral wall portion, and the recess includes a pair of peripheral edges extending in the circumferential direction of the peripheral wall portion. , Is surrounded by a pair of axial edges extending in the axial direction of the peripheral wall portion,
The bottom wall surface of the recess and the axial end edge are continuously provided by an axial side wall surface inclined from the opening side of the recess toward the bottom wall surface,
The radius of curvature R1 of the base end where the bottom wall surface and the axial side wall surface meet is 0.1 mm to 0.5 mm ,
When opening from the state of being attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of bridge portions breaks first, is 160 N · cm or less. Cap for pilfer proof. A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a pilfer proof cap in which an easy-to-break portion composed of a plurality of bridge portions positioned between the slit portions is formed,
The slit portion is formed with a recess recessed in the thickness direction of the peripheral wall portion, and the recess includes a pair of peripheral edges extending in the circumferential direction of the peripheral wall portion. , Is surrounded by a pair of axial edges extending in the axial direction of the peripheral wall portion,
Further, the slit portion is formed with a notch penetrating in the circumferential wall portion thickness direction along one circumferential edge.
The bottom wall surface of the recess and the axial end edge are continuously provided by an axial side wall surface inclined from the opening side of the recess toward the bottom wall surface,
A base end portion where the bottom wall surface and the axial side wall surface meet each other and a peripheral wall portion connected to the other peripheral end edge are connected with a concave curved surface having a radius of curvature R2 of 0.1 mm to 0.8 mm. and,
When opening from the state of being attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of bridge portions breaks first, is 160 N · cm or less. Cap for pilfer proof. The pilfer proof cap according to claim 2, wherein a radius of curvature R1 of a base end where the bottom wall surface and the axial side wall surface meet each other is set to 0.1 mm to 0.5 mm. A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a pill fur proof cap forming device for forming an easily breakable portion composed of a plurality of bridge portions positioned between the slit portions,
A plurality of cutting blade portions extending in a circumferential direction at intervals in order to form the slit portion on the side facing the peripheral wall portion of the outer tool of the molding apparatus, and these having a substantially rectangular shape, and these It is arranged between the cutting blade parts, and a notch part for accommodating the bridge part is formed,
The notch portion includes a pair of inclined wall surfaces that are inclined so as to approach each other from the axial ridge line extending in the axial direction of the cutting edge portion toward the outside of the peripheral wall portion,
The radius of curvature R1 of the meeting part between the cutting edge part and the inclined wall surface is set to 0.1 mm to 0.5 mm ,
When opening from the state where it is attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of the bridge portions is first broken, is 160 N · cm or less. An apparatus for forming caps for pilfer proofs. A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a pill fur proof cap forming device for forming an easily breakable portion composed of a plurality of bridge portions positioned between the slit portions,
A plurality of cutting blade portions extending in a circumferential direction at intervals in order to form the slit portion on the side facing the peripheral wall portion of the outer tool of the molding apparatus, and these having a substantially rectangular shape, and these It is arranged between the cutting blade parts, and a notch part for accommodating the bridge part is formed,
On the side of one circumferential ridge line extending in the circumferential direction of the cutting edge portion, a slit that penetrates in the circumferential wall portion thickness direction is formed in the slit portion,
The curvature radius R2 in the vicinity of at least both ends of the other circumferential ridge line extending in the circumferential direction of the cutting edge is 0.1 mm to 0.8 mm ,
When opening from the state where it is attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of the bridge portions is first broken, is 160 N · cm or less. An apparatus for forming caps for pilfer proofs. A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a pill fur proof cap forming device for forming an easily breakable portion composed of a plurality of bridge portions positioned between the slit portions,
A plurality of cutting blade portions extending in a circumferential direction at intervals in order to form the slit portion on the side facing the peripheral wall portion of the outer tool of the molding apparatus, and these having a substantially rectangular shape, and these It is arranged between the cutting blade parts, and a notch part for accommodating the bridge part is formed,
The notch portion includes a pair of inclined wall surfaces that are inclined so as to approach each other from the axial ridge line extending in the axial direction of the cutting edge portion toward the outside of the peripheral wall portion,
The curvature radius R1 of the meeting part between the cutting edge part and the inclined wall surface is set to 0.1 mm to 0.5 mm,
On the side of one circumferential ridge line extending in the circumferential direction of the cutting edge portion, a slit that penetrates in the circumferential wall portion thickness direction is formed in the slit portion,
The curvature radius R2 in the vicinity of at least both ends of the other circumferential ridge line extending in the circumferential direction of the cutting edge is 0.1 mm to 0.8 mm ,
When opening from the state where it is attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of the bridge portions is first broken, is 160 N · cm or less. An apparatus for forming caps for pilfer proofs. A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a method of manufacturing a pilfer proof cap for forming an easily breakable portion composed of a plurality of bridge portions positioned between the slit portions,
On the side of the outer tool of the molding apparatus facing the peripheral wall portion, a plurality of cutting blade portions extending in the circumferential direction to form the slit portion and having a substantially rectangular shape, and these cutting edges are formed. It is arranged between the blade parts, and a notch part for accommodating the bridge part is formed,
The notch portion includes a pair of inclined wall surfaces that are inclined so as to approach each other from the axial ridge line extending in the axial direction of the cutting edge portion toward the outside of the peripheral wall portion,
The curvature radius R1 of the meeting part between the cutting edge part and the inclined wall surface is set to 0.1 mm to 0.5 mm,
When opening from the state where it is attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of the bridge portions is first broken, is 160 N · cm or less. A method for producing a cap for pilfer proof characterized by the above. A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a method of manufacturing a pilfer proof cap for forming an easily breakable portion composed of a plurality of bridge portions positioned between the slit portions,
On the side of the outer tool of the molding apparatus facing the peripheral wall portion, a plurality of cutting blade portions extending in the circumferential direction to form the slit portion and having a substantially rectangular shape, and these cutting edges are formed. It is arranged between the blade parts, and a notch part for accommodating the bridge part is formed,
On the side of one circumferential ridge line extending in the circumferential direction of the cutting edge portion, a slit that penetrates in the circumferential wall portion thickness direction is formed in the slit portion,
The curvature radius R2 in the vicinity of at least both ends of the other circumferential ridge line extending in the circumferential direction of the cutting edge is 0.1 mm to 0.8 mm,
When opening from the state where it is attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of the bridge portions is first broken, is 160 N · cm or less. A method for producing a cap for pilfer proof characterized by the above. A plurality of slit portions formed in a cap member having a disk-shaped top plate portion and a cylindrical peripheral wall portion depending from the peripheral portion of the top plate portion at intervals in the circumferential direction of the peripheral wall portion And a method of manufacturing a pilfer proof cap for forming an easily breakable portion composed of a plurality of bridge portions positioned between the slit portions,
On the side of the outer tool of the molding apparatus facing the peripheral wall portion, a plurality of cutting blade portions extending in the circumferential direction to form the slit portion and having a substantially rectangular shape, and these cutting edges are formed. It is arranged between the blade parts, and a notch part for accommodating the bridge part is formed,
The notch portion includes a pair of inclined wall surfaces that are inclined so as to approach each other from the axial ridge line extending in the axial direction of the cutting edge portion toward the outside of the peripheral wall portion,
The curvature radius R1 of the meeting part between the cutting edge part and the inclined wall surface is set to 0.1 mm to 0.5 mm,
On the side of one circumferential ridge line extending in the circumferential direction of the cutting edge portion, a slit that penetrates in the circumferential wall portion thickness direction is formed in the slit portion,
The curvature radius R2 in the vicinity of at least both ends of the other circumferential ridge line extending in the circumferential direction of the cutting edge is 0.1 mm to 0.8 mm,
When opening from the state where it is attached to the bottle can, the opening torque value, which is the torque value at which one of the plurality of the bridge portions is first broken, is 160 N · cm or less. A method for producing a cap for pilfer proof characterized by the above.

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