JP2017030853A - Capping method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capping method capable of suppressing deformation of a mouthpiece part and a cap which is generated when capping the cap to a thinned bottle can.SOLUTION: A capping method includes a capping step of molding a female screw part corresponding to a male screw part and a flare crimped to a jaw part by covering a mouthpiece part of a bottle cap with a bottomed cylindrical cap material having a top face part and a cylinder part and pressing an outer peripheral surface of a cap material against the mouthpiece part, and attaching a cap to the mouth piece part. In the capping step, a state of restraining a belt-like range including at least a diameter-reduction start part of a shoulder part in a straight part of a body part is maintained.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a capping method for capping a metal cap on a bottle can having a cap portion on which a thread is formed.

  Bottle cans with re-sealable metal caps are widely used. The cap part of this bottle can has a male thread part, and the cap part is covered with a cap material, and then capping is performed by a capping device (capper), that is, the outer thread of the cap material is male threaded. The cap is attached to the cap portion of the bottle can and capped by forming the thread along the thread of the portion.

  As disclosed in Patent Document 1 and Patent Document 2, the bottle can to which the cap is attached is obtained by integrating the bottom plate portion and the cylindrical side surface portion by drawing and ironing (DI molding) an aluminum alloy plate. And forming a shoulder by reducing the diameter of the opening, and a diameter-expanded cylinder for screw molding above the small-diameter neck formed at the upper end of the shoulder. After the cylindrical portion is formed, the cylindrical portion is subjected to screw forming processing, and the curled portion forming processing is applied to the opening end portion.

By the way, the bottle can manufactured as described above is subjected to a load in the can axis direction when the cap is wound around the cap or the cap portion, and the load in the can axis direction applied to the bottle can is excessive. In such a case, the cap part of the bottle can is deformed into an ellipse, and further, buckling occurs in the neck part and the shoulder part.
In this regard, Patent Document 1 discloses a technique for improving the strength in the radial direction and the axial direction of the bottle can by providing a recess at the upper end of the shoulder. Patent Document 2 discloses a technique for maintaining the strength that does not cause deformation and buckling by partially thinning the bottle can.

JP 2001-213416 A JP 2012-192984 A

  However, further thinning of the bottle can has been promoted, and deformation generated in the cap portion and the cap of the bottle can has become remarkable due to the load applied at the time of capping. Thus, when a deformation | transformation arises in a nozzle | cap | die part and a cap, resistance (torque) at the time of cap opening / closing becomes large. And when resealing the cap that has been opened once, it is misunderstood that the user has closed the cap due to the increased resistance, and the closing operation is stopped halfway, causing leakage of contents. It is a problem to do.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a capping method capable of suppressing deformation of a cap portion that occurs when a cap is capped on a thinned bottle can.

  The capping method of the present invention includes a bottomed cylindrical body, a shoulder formed by reducing the diameter from the upper end of the body, a small-diameter neck formed at the upper end of the shoulder, and the neck. A top part and a tube part on the mouth part of the bottle can having a mouth part formed at the upper part and a male thread part and a jaw part bulging below the male thread part on the mouth part. And forming a female thread portion corresponding to the male screw portion and a flare to be pressed against the jaw portion by pressing the outer peripheral surface of the cap material against the base portion. A capping step of attaching a cap to the base portion, and in the capping step, a state in which a belt-like range including at least a diameter reduction start portion of the shoulder portion of the straight portion of the trunk portion is constrained. It is characterized by maintaining.

In the capping step, as described above, a state in which the band-shaped range including at least the shoulder diameter reduction part of the straight part of the trunk part located at a position away from the cap part which is the cap tightening position is constrained. By maintaining, it is possible to suppress deformation of the bottle can when a large load is applied in the can axis direction. In this case, it is the most desirable form to constrain the entire circumference of the bottle can within the above range, but even when there is a partial gap instead of the entire circumference, the bottle can deforms sufficiently during capping. Can be suppressed. Therefore, maintaining the state in which the belt-like range including at least the diameter-reduction start portion of the shoulder portion in the straight portion of the trunk portion in the present invention is constrained is a range in which deformation of the bottle can occurring at the time of capping can be avoided. In this case, it is sufficient to restrain the band-like range of the straight portion of the trunk portion.
In this way, in the capping step, the deformation of the bottle can can be suppressed by maintaining the band-like range including at least the shoulder diameter reduction portion of the straight portion of the trunk portion in a restrained state. Even when capping a bottle can thinned by this capping method, deformation occurring in the cap portion and the cap of the bottle can can be suppressed.

  In the capping step of the capping method of the present invention, at least the circumferential direction of the bottle can is within a range from a shoulder pressing portion bent toward the radially inner side of the upper end of the shoulder portion to a reduced diameter starting portion of the shoulder portion. It is good to maintain the state restrained linearly.

  In the capping process, in addition to maintaining the belt-like range including at least the shoulder diameter reduction start portion of the straight portion of the trunk portion, the shoulder pressing portion to the shoulder diameter reduction start portion Within the range, by maintaining a state in which at least the circumferential direction of the bottle can is constrained in a linear shape, the effect of suppressing deformation when a large load acts in the can axis direction can be further enhanced. In this case, it is not necessary to constrain the entire region within the range from the shoulder pressing portion to the start of diameter reduction of the shoulder portion, and it is sufficient to constrain at least a partial region in the can axis direction in the circumferential direction.

  In the capping method of the present invention, when a cap is attached to a cap portion of a bottle can whose buckling strength against compression in the can axis direction is 1400 N or more and less than 1800 N, in the capping step, the cap material is used as the cap. The load in the can axis direction to be pressed against the portion is 700N to 900N, the radial pressing load for forming the female screw portion is 104.1N to 117.3N, and the radial pressing load for forming the flare is 77.N. It is good to set it as 8N or more and 90.9N or less.

  Even in the case of a thin bottle can whose column strength, which is a buckling strength against compression in the axial direction of the can, is 1400 N or more and less than 1800 N, in the capping process, at least a shoulder diameter reduction start portion of the straight portion of the trunk portion By maintaining the state in which the band-like range including the above is constrained, deformation when a large load acts in the can axis direction can be suppressed. At this time, the load in the can axis direction for pressing the cap material against the base portion is set to 700 N or more and 900 N or less, the radial pressing load for forming the female screw portion is set to 104.1 N or more and 117.3 N or less, and the radius for forming the flare By setting the pressing load in the direction to 77.8 N or more and 90.9 N or less, it is possible to reliably suppress the deformation of the bottle can that occurs during capping.

  According to the present invention, maintaining a state in which a belt-like range including at least a shoulder diameter reduction start portion of a straight portion of a bottle can located at a position away from a cap portion that is a cap tightening position is constrained. And even if it is a thin bottle can, the deformation | transformation of a nozzle | cap | die part and a cap which arise at the time of capping can be suppressed.

It is principal part sectional drawing explaining the capping method of 1st Embodiment of this invention using a capping apparatus. It is a bottom view of the capping head part of the capping apparatus shown in FIG. It is sectional drawing of the capping head part of the capping apparatus shown in FIG. It is a half sectional view explaining mounting of a restraining ring member. It is a half cross-sectional view of the cap part of the bottle can equipped with the restraining ring member, and shows a state in which the restraining ring member is fitted to the lower part of the shoulder pressing part of the bottle can. It is principal part sectional drawing of the shoulder part of a bottle can, and is a figure explaining a diameter-reduction start part. It is explanatory drawing explaining the conveyance path | route of a bottle can and a bottle can with a cap. It is a figure explaining the capping method of 2nd Embodiment of this invention, and is a half cross section figure of the bottle can which shows the state which made the restraint ring member fit only in the straight part containing the diameter-reduction start part of the shoulder part of a bottle can. It is. It is a figure explaining the capping method of 3rd Embodiment of this invention, and is a half cross section figure of a nozzle | cap | die part which shows the state which made the restraint ring member fit to the straight part and shoulder part of a bottle can. It is a figure explaining the capping method of 4th Embodiment of this invention, and is a half cross section figure of a nozzle | cap | die part which shows the state which made the restraint ring member fit to the straight part and shoulder pressing part of a bottle can. It is a half sectional view of a cap part showing the state where a restraint ring member was made to fit only in the shoulder part of a bottle can. It is a half cross-sectional view of the base part showing a state in which the restraining ring member is fitted to the straight part and the shoulder part of the bottle can, and shows a case where the fitting range by the shoulder part is set narrow. It is a half cross-sectional view of the bottle can showing a state in which the restraint ring member is fitted only to the straight portion of the bottle can, and the restraint ring member is fitted to the straight portion in a range excluding the diameter reduction start portion of the shoulder portion. State.

Hereinafter, an embodiment of a capping method according to the present invention will be described with reference to the drawings.
As shown in FIG. 1, after the bottle can 2 is filled with the contents, the cap 3 (cap material 30) is attached to the cap portion 21 to manufacture the bottle can 1 with the cap.

  The bottle can 2 is made of aluminum or an aluminum alloy, and is formed by drawing and ironing. As shown in FIG. 4, the bottle can 2 includes a bottomed cylindrical barrel portion 22, a tapered shoulder portion 23 that gradually decreases in diameter from the upper end of the barrel portion 22, and the shoulder portion 23. It is formed in a bottle shape having a cylindrical small-diameter neck portion 24 that extends upward from the upper end of the lip portion, and a base portion 21 that is formed in an upper portion than the neck portion 24. Moreover, the trunk | drum 22 is formed from the bottom part 20b of the bottle can 2, and the cylindrical straight part 29 extended upwards from the peripheral part of this bottom part 20b. The base portion 21 includes a curled portion 25 formed at the tip of the opening portion 20a, a male screw portion 26 formed below the curled portion 25, and a jaw portion formed to bulge below the male screw portion 26. 27 is formed.

The cap member 30 that is wound around the base portion 21 of the bottle can 2 to become the cap 3 is made of aluminum or an aluminum alloy, like the bottle can 2. Further, as shown in FIG. 4, the cap member 30 has a bottomed tubular shape having a circular top surface portion 31 and a cylindrical tubular portion 32, and the tubular portion 32 includes a knurl 33, a groove 34, and a bead 35. And a flare 36 are formed. Further, a liner 4 that is a sealing material is provided inside the top surface portion 31. And the cap material 30 is covered by covering the base part 21 after filling the contents in the bottle can 2, and being attached by being tightened. Specifically, by forming the cylindrical portion 32 of the cap material 30 so as to follow the male screw portion 26 and the jaw portion 27 of the base portion 21, the female screw portion 37 is formed in the cylindrical portion 32, and The flare 36 at the lower end is wound around the jaw 27, and the cap 3 and the base 21 are fixed in a screwed state.
Hereinafter, the thing before mounting | wearing with the bottle can 2 is called the cap material 30, and the thing in which the internal thread part 37 after mounting | wearing was formed is called the cap 3. FIG.

  As described above, in order to perform the capping process by attaching the cap material 30 to the cap portion 21 of the bottle can 2, for example, a capping device including a plurality of capping heads 101 as shown in FIG. 1 is used. Then, the cap material 30 is attached to each bottle can 2 by any one of the plurality of capping heads 101. Each capping head 101 includes a pressure block 60 and a capping roll 70. The capping roll 70 includes a first roll 71 as an RO roll (roll-on roll) and a second roll 72 as a PP roll (pill fur proof roll). The first roll 71 has a roll support mechanism 81. The second roll 72 is rotatably attached to the support block 12 via a roll support mechanism 82.

As shown in FIG. 3, the pressure block 60 presses the top surface portion 31 of the cap material 30 in a state where the cap portion 30 is covered with the cap portion 21 of the bottle can 2, and a step portion 31 a is formed on the outer peripheral portion of the top surface portion 31. Form. Further, the capping roll 70 is configured such that the female thread portion 37 is formed on the cap material 30 by the first roll 71 and the flare 36 of the cylindrical portion 32 is wound around the jaw portion 27 by the second roll 72.
The capping roll 70 is configured to include at least one first roll 71 and second roll 72. In the capping head 101 of the capping apparatus 100 of this embodiment, two first rolls 71 and two second rolls 72 are provided as shown in FIG.

  Further, the capping device 100 is provided with a restraining ring member 5A as shown in FIG. As shown in FIGS. 5 and 6, the constraining ring member 5 </ b> A is an outer diameter constraining portion that fits into a belt-shaped range H including the diameter reduction starting portion P of at least the shoulder portion 23 of the straight portion 29 of the trunk portion 22. 51a is provided. In addition, the restraining ring member 5A includes at least the bottle can 2 within a range from the shoulder pressing portion 28 bent toward the radially inner side of the upper end of the shoulder portion 23 of the bottle can 2 to the reduced diameter start portion P of the shoulder portion 23. The fitting hole part 52a which fits linearly in the circumferential direction is provided. The diameter reduction start portion P of the shoulder portion 23 is a connecting portion between the upper end of the straight portion 29 of the trunk portion 22 and the lower end of the shoulder portion 23 as shown in FIG. The inflection point between the part 23 is shown. Thus, as shown in FIG. 6, the shoulder portion 23 of the bottle can 2 has a shape including the arc portion 23 s and the tapered portion 23 t.

  Further, the constraining ring member 5A of the present embodiment shown in FIG. 5 is provided with an insertion hole 53a continuous to the fitting hole 52a, and the inner diameter Da of the insertion hole 53a is the tube of the cap member 30. It is formed larger than the outer diameter of the portion 32. For this reason, by putting the cap member 30 on the cap part 21 of the bottle can 2 and then placing it on the shoulder part 23 of the bottle can 2 by covering the restraint ring member 5A from the opening 20a side of the bottle can 2, The outer diameter restricting portion 51a is fitted to the upper portion of the straight portion 29 of the trunk portion 22, and the fitting hole portion 52a is fitted to a part of the shoulder portion 23 and easily attached. Can do. In this way, the outer diameter restraining portion 51a of the restraining ring member 5A is fitted to the upper portion of the straight portion 29, and the fitting hole portion 52a is fitted to the shoulder portion 23 of the bottle can 2. Thereby, the state which restrained the bottle can 2 in these fitting parts is maintained. Further, the restraining ring member 5A can be easily positioned (centered) between the restraining ring member 5A and the bottle can 2 by the outer diameter restraining portion 51a and the fitting hole portion 52a.

The constraining ring member 5A is detachably provided on the bottle can 2 and is maintained attached to the shoulder portion 23 of the bottle can 2 as shown in FIG. It is removed from the bottle can 1.
Specifically, as shown in FIG. 7, while the bottle can 2 passes through the bottle conveyance path 91 in the conveyance path of the bottle can 2, the cap member 30 is put on the cap portion 21 of the bottle can 2 and restrained. The ring member 5 </ b> A is attached to the bottle can 2. That is, the restraining ring member 5A is mounted on the bottle can 2 until the capping station 92 provided with the capping head 101 moves to the capping station 92. Then, the cap material 30 is attached to the base portion 21 with the restraining ring 5 </ b> A attached at the capping station 92. Thereafter, the bottled can 1 with the cap 3 to which the cap 3 is attached moves to the bottle discharge path 93, and the restraining ring member 5 </ b> A is removed from the bottle can 1 with cap while passing over the bottle discharge path 93.
For example, as shown by a two-dot chain line in FIG. 1, the constraining ring member 5 </ b> A can be configured to be supported by the apparatus main body (not shown) so as to be vertically movable outside the capping head 101 in the radial direction. However, only the restraining ring member 5A can be detachably attached.

Next, a capping method according to this embodiment in which capping is performed using the capping apparatus 100 including the capping head 101 configured as described above will be described.
First, the cap member 30 is put on the cap portion 21 of the bottle can 2 and the restraint ring member 5A is easily mounted on the bottle can 2 by placing the restraint ring member 5A on the shoulder portion 23 of the bottle can 2. Can do. Thereby, the outer diameter restraining part 51a of the restraining ring member 5A is fitted to the upper part of the straight part 29 of the bottle can 2, and the restraining ring member 5A and the bottle can 2 are aligned, and the outer diameter restraining part thereof. In the fitting part between 51a and the straight part 29, the state which restrained the bottle can 2 is maintained. That is, the belt-shaped range H including the diameter reduction start portion P of the shoulder portion 23 of the straight portion 29 is maintained in a constrained state by the outer diameter restricting portion 51a. In addition, the fitting hole 52 a abuts on a part of the shoulder 23 of the bottle can 2, and the bottle is formed at the fitting portion between the fitting hole 52 a of the restraining ring member 5 A and the shoulder 23 of the bottle can 2. The state where the can 2 is restrained is maintained. That is, at least the circumferential direction of the bottle can 2 is linearly constrained by the fitting hole portion 52a within the range from the shoulder pressing portion 28 to the diameter reducing start portion P of the shoulder portion 23.

Then, in the state where the bottle can 2 is restrained by the restraining ring member 5A in this way, a capping step is performed as shown in FIG.
First, the pressure block 60 is placed on the upper part of the cap member 30, and the top surface portion 31 of the cap member 30 is pressed in the direction of the bottom 20b of the bottle can 2 by the urging force of the compression spring 62 due to the vertical load applied to the entire head. A step portion 31 a is formed on the shoulder portion of 30.
Next, the 1st roll 71 and the 2nd roll 72 are pressed against the cylinder part 32 of the cap material 30 with the state which pressed the top surface part 31 of this cap material 30 maintained. Then, by rotating the capping head 101, the first roll 71 is rotated along the male screw part 26 of the base part 21, and the female screw part 37 corresponding to the male screw part 26 is formed in the cylindrical part 32 of the cap member 30. Then, the second roll 72 is rolled along the jaw part 27, the flare 36 of the cylinder part 32 is wound around the jaw part 27, and the resealable cap 3 is attached to the base part 21.

  At this time, the two first rolls 71 provided on the capping head 101 are respectively pressed against the cylindrical portion 32 and run from the opening 20a side of the base portion 21 to the jaw portion 27 side along the thread valley of the male screw portion 26. Moving. Further, the two first rolls 71 are sequentially rotated and moved along the thread valley of the male thread portion 26, whereby the thread valley of the female thread portion 37 is formed with respect to the thread of the male thread portion 26, and this thread valley is formed. By doing so, the thread of the female screw portion 37 is formed so that the shape of the thread valley of the male screw portion 26 is transferred therebetween. In this way, the operation of pressing the cylindrical portion 32 of the cap member 30 along the thread valley of the male screw portion 26 of the base portion 21 by each first roll 71 is repeated twice, and the female screw portion is performed by these two operations. 37 is processed. That is, in the first molding by the first roll 71, preliminary processing is performed in which the cylindrical portion 32 of the cap material 30 gently follows the shape of the male screw portion 26 of the base portion 21, and the female screw portion 37 is formed in the second molding. Molded. As a result, the cap-equipped bottle can 1 in which the cap 3 is attached to the cap portion 21 of the bottle can 2 is manufactured.

  Thus, in the capping step, the belt-shaped range H including at least the diameter-reduction starting portion P of the shoulder portion 23 of the straight portion 29 located away from the cap portion 21 that is the winding position of the cap 3 is restrained. While maintaining the state, the state where the circumferential direction of the bottle can 2 is constrained linearly within the range from the shoulder pressing portion 28 to the diameter reducing start portion P of the shoulder portion 23, the straight portion 29 and the shoulder By preventing deformation of the constrained portion with the portion 23, deformation of the other portion of the bottle can 2 that occurs when a large load acts in the can axis direction can be suppressed.

  In the present embodiment, the belt-shaped range H including the diameter reduction start portion P of the shoulder portion 23 is constrained by fitting the outer diameter restraining portion 51a of the restraining ring member 5A to the straight portion 29 of the bottle can 2. In this way, the state in which the belt-shaped range H is constrained by the outer diameter constraining portion 51a is a fitting relationship that allows the constraining ring member 5A and the bottle can 2 to be easily attached and detached. It ’s enough. That is, the outer diameter restricting portion 51a and the straight portion 29 suppress deformation of the bottle can 2 that occurs during capping even when the constraining ring member 5A and the bottle can 2 have a gap that can be easily attached and detached. can do.

  Moreover, in the said embodiment, as shown in FIG. 5, by using restraint ring member 5A, in the capping process, it is a strip | belt shape including the diameter reduction start part P of at least the shoulder part 23 of the straight part 29 of the bottle can 2. As shown in FIG. However, the present invention is not limited to this. However, the present invention is not limited to the above-described range H and the range from the shoulder pressing portion 28 to the reduced diameter starting portion P of the shoulder portion 23. In addition, the belt-like range H including at least the shoulder diameter reduction start portion P of the shoulder portion 23 in the straight portion 29 and the range from the shoulder pressing portion 28 to the diameter reduction start portion P of the shoulder portion 23 are restrained. It is not necessary to make the state, and by making only the band-like range H constrained, deformation of the bottle can 2 that occurs during capping can be sufficiently suppressed.

  For example, as in the second embodiment shown in FIG. 8, only the straight portion 29 can be constrained by using a constraining ring member 5B that is entirely cylindrical. The constraining ring member 5B is provided with an outer diameter constraining portion 51b that fits with the entire straight portion 29 of the body portion 22 including the diameter reduction starting portion P of the shoulder portion 23, and is fitted with the shoulder portion 23. There are no holes. For this reason, the restraint ring member 5B is covered from above the base portion 21 of the bottle can 2, or the bottle can 2 is inserted into the outer diameter restraint portion 51b of the restraint ring member 5B from the bottom portion 20b, thereby restraining the ring. The member 5B can be easily attached to the bottle can 2.

In addition to the belt-shaped range H, as in the restraint ring member 5A of the first embodiment shown in FIG. 5, the state in which the range from the shoulder pressing portion 28 to the diameter reduction start portion P of the shoulder portion 23 is restrained; By doing, compared with the state which restricted only the strip | belt-shaped range H, the deformation | transformation inhibitory effect of the bottle can 2 produced at the time of capping can further be heightened.
In this case, regarding the range from the shoulder pressing portion 28 to the diameter reducing start portion P of the shoulder portion 23, it is not necessary to constrain the entire range, and at least the can as in the constraining ring member 5 </ b> A of the first embodiment. In a partial region in the axial direction, it is sufficient to constrain the circumferential direction of the bottle can 2 in a linear shape. Further, in the linear restraint within the range from the shoulder pressing portion 28 to the diameter reducing start portion P of the shoulder portion 23, it is the most desirable form to restrain the entire circumference of the bottle can 2. Instead, even when there is a partial gap, the deformation of the bottle can 2 that occurs during capping can be sufficiently suppressed.
In this way, in the capping step, the deformation of the bottle can 2 is suppressed by maintaining the straight part 29 and the shoulder part 23 at a position away from the cap part 21 that is the tightening position of the cap 3. Therefore, even when capping the thinned bottle can 2 by the capping method of the present invention, it is possible to suppress deformation that occurs in the cap portion 21 and the cap 3 of the bottle can 2.

In the restraint ring member 5A of the first embodiment, the fitting hole 52a is fitted at the lower portion of the shoulder pressing portion 28 of the bottle can 2, but for example, the restraint ring member 5C shown in FIG. It is good also as restraining places other than the lower part of the shoulder pressing part 28 like restraint ring member 5D shown in FIG.
The constraining ring member 5C shown in FIG. 9 has a fitting hole portion 52c formed along the tapered shape of the shoulder portion 23, and the tapered surface of the fitting hole portion 52c is fitted to the tapered surface of the shoulder portion 23. The shoulder portion 23 is fitted with a width. Further, an insertion hole 53 c is provided continuously to the fitting hole 52 c, and the inner diameter Dc of the insertion hole 53 c is formed larger than the outer diameter of the cylindrical portion 32 of the cap member 30. For this reason, the restraint ring member 5 </ b> B can be easily attached to the bottle can 2 by placing the restraint ring member 5 </ b> C on the shoulder portion 23 from above the base portion 21 of the bottle can 2. In addition, the code | symbol 51c shown in FIG. 9 shows the outer-diameter restraint part fitted with the strip | belt-shaped range H. FIG.

On the other hand, the constraining ring member 5D shown in FIG. 10 is configured such that the fitting hole portion 52d is fitted to the shoulder pressing portion 28, and the inner diameter Dd of the fitting hole portion 52d is outside the cylindrical portion 32 of the cap member 30. It is formed smaller than the diameter. In this case, the constraining ring member 5D can be configured by combining a plurality of arc-shaped members divided in the circumferential direction, and each arc-shaped member can be attached to and detached from the bottle can 2 by moving forward and backward in the radial direction. Can do. In addition, the code | symbol 51d shown in FIG. 10 shows the outer-diameter restraint part fitted with the strip | belt-shaped range H. FIG.
In the cases shown in FIGS. 9 and 10 as well, in addition to the band-shaped range H of the straight portion 29, the range from the shoulder pressing portion 28 to the diameter reduction starting portion P of the shoulder portion 23 by the restraining rings 5C and 5D. Since the state which restrained the inside can be maintained, the effect similar to the case where restraint ring member 5A is used can be acquired.

Next, an experiment was conducted to confirm the effect of the capping method of this embodiment.
(Evaluation of column strength)
The column strength is determined by compressing the plate at a speed of 5 (mm / min) by bringing a flat plate into contact with the upper end (opening portion) of the bottle base while restraining the bottom of the bottle can from being deformed by a load. This is the load when bending is started. The column strength was measured using a Shimadzu tester (model number AG-50kNG).
The bottle can used in this test is made of aluminum containing 410 ml, and is a bottle can thinner than a normal (current product) bottle can. The thinned bottle can is a bottle can having a buckling strength (column strength) with respect to compression in the can axis direction of 1400 N or more and less than 1800 N. In contrast to a thinned bottle can, The column strength is 1800N or more and 1900N or less.

And about such a thinned bottle can, measurement of column intensity | strength at the time of mounting | wearing with various restraint ring members 5A, 5B, and 5E-5G shown in FIG.5, FIG.8, FIG.11-13 in a bottle can. Went.
5, 8, 12, and 13 are constrained ring members 5A, 5B, 5F, and 5G that have outer diameter restraining portions (reference numerals 51a, 51b, and 51f, respectively) that restrain the straight portion 29 of the bottle can 2. , 51g). 5, FIG. 11, and FIG. 12, the constraining ring members 5A, 5E, and 5F are formed with fitting holes (indicated by reference numerals 52a, 52e, and 52f, respectively), and these constraining ring members 5A. , 5E, 5F, the constraining ring members 5A, 5F have shapes having both outer diameter restraining portions (51a, 51f) and fitting hole portions (52a, 52f). On the other hand, the constraining ring member 5E shown in FIG. 11 has a fitting hole 52e and an insertion hole 53e formed without forming an outer diameter constraining part. Further, the constraining ring member 5G shown in FIG. 13 is formed by forming only the outer diameter constraining part 51g without forming the fitting hole part.

  In the restraining ring members 5A, 5B, 5F, and 5G having these outer diameter restraining portions, the inner diameter Do of the outer diameter restraining portion is set to 66.2 mm. Further, in the restraining ring member 5A shown in FIG. 5, the inner diameter Da of the insertion hole portion 53a is set to 40.5 mm, and the fitting hole portion 52a is fitted at the lower portion of the shoulder pressing portion 28 of the bottle can 2. . The constraining ring member 5E shown in FIG. 11 has an inner diameter De of the insertion hole portion 53e of 44.0 mm, a fitting hole portion 52e formed along the tapered shape of the shoulder portion 23, and the fitting hole portion 52e. The tapered surface is fitted to the tapered surface of the shoulder 23, and is fitted with a width. Further, the constraining ring member 5F shown in FIG. 12 has an inner diameter Df of the insertion hole 53f of 52.0 mm and a fitting hole 52f formed along the tapered shape of the shoulder 23. A range in which the tapered surface of the portion 52f is fitted to the tapered surface of the shoulder portion 23 is narrowly formed. Further, the constraining ring members 5A (FIG. 5) and 5F (FIG. 11) having both the outer diameter restraining portion and the fitting hole portion are fitted to the outer diameter restraining portion and the straight portion 29, that is, the shoulder portion 23. The band-shaped range H including the reduced diameter starting portion P was set to a width of 10 mm. On the other hand, the constraining ring member 5G shown in FIG. 13 has a fitting range between the outer diameter constraining portion 51g and the straight portion 29, except for a band-shaped range H (10 mm width) including the diameter reducing start portion P of the shoulder portion 23. Set. Moreover, as shown in Table 1, various restraint ring members 5A, 5B, 5E-5G were formed of PET (polyethylene terephthalate resin) or SKD (die steel).

  Table 1 shows the results of the column strength measurement. The number of cans for evaluating column strength was 10 cans, and the standard deviation was calculated together with the average value, maximum value, and minimum value from the column strength data of 10 cans.

As can be seen from the results when using the restraint ring member 5B of Table 1, by maintaining the state of restraining the band-shaped range H including the diameter reduction start portion P of at least the shoulder portion 23 of the straight portion 29, The column strength can be improved as compared with the case where no restraining ring member is used. On the other hand, even when the restraint ring member 5G that restrains the straight portion 29 within the range not including the diameter reduction start portion P of the shoulder portion 23 is used, the column strength is slightly smaller than when the restraint ring member is not used. I was able to improve.
Further, as can be seen from the results of the constraining ring members 5A, 5F, and 5B, in addition to the band-shaped range H of the straight portion 29, a part of the range from the shoulder pressing portion 28 to the reduced diameter start portion P of the shoulder portion 23 The column strength can be further improved by maintaining the state where at least the circumferential direction of the bottle can 2 is constrained in a linear shape.

Further, as can be seen from the result of the restraining ring member 5A, the material for forming the restraining ring member may be a case where the material is made of PET having a relatively low rigidity, or a case where the material is made of SKD having a high rigidity. There was no significant difference, and in either case, the column strength could be improved.
On the other hand, in the constraining ring member 5E provided with only the fitting hole portion without having the outer diameter constraining portion, it was not possible to obtain a good result showing an improvement in column strength. In particular, in the case of the restraint ring member 5E formed of PET, the restraint ring member 5E is lifted from the shoulder 23 during the column strength measurement, and the bottle can 2 is restrained by the fitting hole 52e. I could not. From the above results, in addition to the belt-shaped range H including at least the diameter reduction start portion P of the shoulder portion 23 in the straight portion 29, the range from the shoulder pressing portion 28 to the diameter reduction start portion P of the shoulder portion 23 is constrained. It was confirmed that the column strength could be further improved by maintaining this state.

(Evaluation by capping)
Next, bottle cans with caps obtained by capping bottle caps were prepared, and each bottle can with cap was evaluated. From the evaluation result of the column strength, in addition to the belt-shaped range H including at least the reduced diameter start portion P of the shoulder portion 23 in the straight portion 29, the range from the shoulder pressing portion 28 to the reduced diameter start portion P of the shoulder portion 23. It has been found that the configuration in which a part of the bottle is constrained can satisfactorily suppress the deformation of the bottle can 2 and is highly effective in improving the column strength. Therefore, three types of experiments were conducted for the case where either one of the two types of constraining ring members 5A and 5C shown in FIG. 5 or 9 was used and the case where capping was performed without using the constraining ring member.

5 is the same as that used in the evaluation of the column strength, the inner diameter Da of the insertion hole 53a is set to 40.5 mm, and the fitting hole 52a is the bottle can 2. The lower portion of the shoulder pressing portion 28 is fitted. Further, the constraining ring member 5C shown in FIG. 9 has an inner diameter Dc of the insertion hole portion 53c of 44.0 mm, a fitting hole portion 52c formed along the tapered shape of the shoulder portion 23, and the fitting hole portion The tapered surface 52c is fitted to the tapered surface of the shoulder portion 23, and is fitted with a width. Further, the outer diameter restraining portion 51a of the restraining ring member 5A and the outer diameter restraining portion 51c of the restraining ring member 5C are both set to have an inner diameter Do of 66.2 mm. A fitting range between 51c and the straight portion 29, that is, a band-shaped range H including the diameter reduction start portion P of the shoulder portion 23 was set to a width of 10 mm.
For the capping test, a thinned bottle can similar to the bottle can used in the column strength evaluation was used.

As the cap material, a cap material for pilfer proof having a nominal cap outer diameter of 38 mm formed from an aluminum alloy plate having a thickness of 0.22 mm was used. The liner used was a two-layer sheet comprising a soft layer made of TPS (styrene elastomer) and a hard layer made of PP (polypropylene).
As the pressure block used for capping, a block having a diameter of 35.8 mm and a drawing depth of 1.8 mm was used. Moreover, the top pressure (load in the can axis direction of the bottle can at the time of capping) was set to the conditions (700 to 1000 N) shown in “TP” of Table 2 for capping. Further, the pressing load of the first roll (radial load acting on the bottle can at the time of capping) is set to the conditions (104.1 to 117.3N) shown in “RO” of Table 2, and the second roll The pressing load was set to the conditions shown in “PP” in Table 2 (77.8 to 90.9 N). And each capping of each sample was performed by twice processing with the 1st roll.

The bottle cans are filled with 375 g (5 ° C.) of water containing gas and capped, and the initial internal pressure of each bottle can with cap is set to be equivalent to 1.0 (kg / cm ² ) at 20 ° C. A bottle can with a cap was prepared. About the produced bottle can with a cap, the following item was evaluated.

(Screw resistance torque evaluation)
The number of evaluation cans was 5 cans. After opening the bottle can with cap once, the maximum torque required when the cap was returned to the position 180 ° before the original position and closed was measured, and the maximum torque was defined as the screw portion resistance torque. The case where there is even one can with a screw resistance torque of 10 N · cm or more is judged as “No”, and the case where there is also one can with a screw resistance torque of 5 N · cm or more and less than 10 N · cm is acceptable. The case where the screw portion resistance torque of all five cans was less than 5 N · cm was evaluated as “good”.

(Deformation evaluation)
The number of evaluation cans was 5 cans. Using the bottle can after opening, the base part of the bottle can was touched, and evaluation was performed by confirming the tactile sensation. Points were assigned 0 to 5 points for each can, and the total points of 5 cans were evaluated. Pointing is “0” point when there is no deformation, “1” point when the presence or absence of deformation cannot be determined, “2” point when small deformation is recognized, and “3” when moderate deformation is recognized. “Point”, and “4” point when a large deformation is recognized. The case where the total point of 5 cans is 5 points or more and the case where 2 or more cans are also 1 can is determined as “No”, and the case where the total points of 5 cans is 1 point or more and less than 5 points is acceptable. The case where the total point of 5 cans was 0 point, that is, the case where no deformation was confirmed in all 5 cans was evaluated as “good”.
The results are shown in Table 2.

  As can be seen from the results in Table 2, the restraint ring members 5A and 5C are used to restrain the belt-shaped range H including the diameter-reduction starting portion P of the shoulder portion of the straight portion of the bottle can and to hold the shoulder. By constraining the range from the part to the reduced diameter start part of the shoulder part, compared with the case where capping is performed without any restriction, the resistance resistance of the screw part can be reduced. Deformation can also be suppressed. In addition, as for the restraint position of the bottle can, similarly to the lower portion of the shoulder pressing portion of the bottle can (restraint ring member 5A) and the shoulder portion (restraint ring member 5C), the screw portion resistance torque is reduced. It was possible to suppress the deformation of the base part. Further, even in the restraint range of the bottle can, even when the entire circumference is restrained by almost line contact like the restraint ring member 5A, the entire circumference of the bottle can has a width by surface contact like the restraint ring member 5C. Even in the case of restraining by surface contact, similarly, it was possible to reduce the screw portion resistance torque and to suppress the deformation of the base portion.

  Further, as can be seen from the results in Table 2, the top pressure is applied to the thinned bottle can whose buckling strength against compression in the can axis direction evaluated in this example is 1400 N or more and less than 1800 N. 700N or more and 900N or less, the pressing load of the first roll for forming the female thread portion is 104.1N or more and 117.3N or less, and the second roll pressing load for forming the flare is 77.8N or more and 90.9N or less and the cap is wound. By tightening, the deformation of the bottle can occurring at the time of capping can be reliably suppressed.

  In addition, this invention is not limited to the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Bottle can with cap 2 Bottle can 3 Cap 4 Liner 5A-5G Restraint ring member 12 Support block 21 Base part 22 Body part 23 Shoulder part 24 Neck part 25 Curl part 26 Male thread part 27 Jaw part 28 Shoulder pressing part 29 Straight part 30 Cap Member 31 Top surface portion 32 Tube portion 33 Knurl 34 Groove 35 Bead 36 Flare 37 Female thread portions 51a to 51d, 51f, 51f Outer diameter restricting portions 52a, 52c to 52f Fitting hole portions 53a, 53c to 53f Insertion hole portion 60 Pressure block 70 Capping roll 71 First roll 72 Second roll 81, 82 Roll support mechanism 100 Capping device 101 Capping head

Claims (3)

A cylindrical body with a bottom, a shoulder formed by reducing the diameter from the upper end of the trunk, a small-diameter neck formed at the upper end of the shoulder, and formed at a portion above the neck. A bottomed cylindrical shape having a top surface portion and a tube portion on the mouthpiece portion of the bottle can having a mouthpiece portion and a male screw portion and a jaw portion bulging below the male screw portion formed on the mouthpiece portion The cap material is covered, and the outer peripheral surface of the cap material is pressed against the base part, thereby forming a female thread part corresponding to the male thread part and a flare to be crimped to the jaw part, and cap the base part. Having a capping process to deposit
In the capping step, the capping method is characterized in that a state in which a belt-like range including at least the diameter-reduction starting portion of the shoulder portion is constrained among the straight portions of the trunk portion is maintained.   In the capping step, at least a circumferential direction of the bottle can is constrained linearly within a range from a shoulder pressing portion bent toward the radially inner side of the upper end of the shoulder portion to a reduced diameter starting portion of the shoulder portion. The capping method according to claim 1, wherein the capping method is maintained. When the cap is attached to the cap portion of the bottle can whose buckling strength against compression in the can axis direction is 1400 N or more and less than 1800 N,
In the capping step,
The load in the can axis direction for pressing the cap material against the base part is 700N or more and 900N or less,
The radial pressing load for forming the female screw portion is 104.1 N or more and 117.3 N or less,
The capping method according to claim 1 or 2, wherein a radial pressing load for forming the flare is 77.8 N or more and 90.9 N or less.

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