JP4667971B2 - cap - Google Patents

Description

  The present invention relates to a cap that is screwed onto a mouthpiece of a bottle can filled with a beverage.

  2. Description of the Related Art Conventionally, as a container for filling and sealing beverages for sale, for example, as shown in Patent Document 1 below, a bottle can with a cap in which a cap is screwed onto a base portion of a bottle can has been widely used. A cap provided for this kind of bottled can with a cap is generally provided with a top plate portion and a peripheral wall portion substantially hanging from the peripheral edge portion of the top plate portion. An easy-to-break part having a plurality of slit parts extending inward and radially indented in the circumferential direction is provided via a bridge, and the slit part is formed with a slit penetrating the peripheral wall part in the thickness direction. Yes.

  After this kind of cap is arranged in the base part of the bottle can, the peripheral part of the top plate part is pressed downward in the can axis direction to form a step part (step part forming step). While maintaining the pressure, the outer peripheral surface of the peripheral wall portion is pressed radially inward along the male screw portion of the base portion to form a female screw portion on the peripheral wall portion (female screw portion forming step). ) By pressing the open end of the peripheral wall portion inward in the radial direction so as to be wound around the bulging portion that is connected to the lower end in the can axis direction of the male screw portion and bulges outward in the radial direction. (Bottom winding step), screwed into the bottle can base, to obtain a bottle can with cap.

When opening such a bottle can with a cap, the cap is rotated relative to the periphery of the can axis in a direction in which the female screw portion is loosened with respect to the bottle can male screw portion. It is moved upward in the can axis direction with respect to the part. At this time, since the open end portion is wound around the bulging portion connected to the lower end in the can axis direction of the external thread portion of the bottle can base, the movement of the open end side of the cap is prevented. . Thereby, in the initial stage of the movement of the cap, the bridge is broken, and the upper part of the cap on the top plate part side from the easily breakable part is removed from the base part, and the cap on the open end side from the easily breakable part. The lower part remains in the base part.
JP 2003-072798 A

By the way, in the conventional cap, when the cap is opened, the open end portion is caused by a force directed upward in the can axis direction that acts on the open end portion of the bulge portion of the bottle can base portion. The bridge is not broken by moving the inner peripheral surface upward along the outer peripheral surface of the bulging portion and moving upward in the can axis direction. In some cases, the open end portion is completely removed from the bulging portion. That is, the movement of the open end portion cannot be prevented at the time of opening the plug, and the bridge may not be broken and the slippage may occur.
When the cap thus opened is resealed to the bottle can base, the open end is caught by the open end of the cap base and cannot be resealed.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cap capable of suppressing the occurrence of slipping off when opening a bottle can with a cap.

In order to solve such a problem and achieve the above object, the cap of the present invention includes a top plate portion, and a cap body provided with a peripheral wall portion substantially suspended from a peripheral edge portion of the top plate portion; A liner disposed on the inner surface of the top plate portion, and a plurality of slit portions extending in the circumferential direction and recessed inward in the radial direction are formed in the circumferential wall portion via the bridge in the circumferential direction. The slit portion is formed with a slit penetrating the peripheral wall portion in the thickness direction, and the peripheral wall portion is screwed into a male screw portion formed in a cap portion of the bottle can. A cap that is screwed into a cap portion of a bottle can by winding an open end portion into a bulging portion that is connected to the lower end in the can axis direction of the male screw portion, and the hardness of the open end portion is: 10% to 18% higher than the top plate And wherein the Rukoto.
The open end may be 82 or more in micro Vickers (Hv50g) hardness.

  In this case, since the hardness of the open end portion of the cap is set in the above range, when opening the bottle can with cap, the can is attached to the open end portion wound around the bulging portion of the bottle can base. Even when a force directed upward in the axial direction is applied, the open end can be firmly locked to the bulging portion. Therefore, at the time of the opening, the open end is moved upward in the can axis direction while the inner peripheral surface of the bulging portion is expanded along the outer peripheral surface, so that the bridge is not broken. It is possible to prevent the open end portion from completely slipping out of the bulging portion. As a result, the bridge can be reliably broken at the time of opening, and the entire cap including the open end side can be prevented from being detached from the bottle can base.

  According to the cap concerning this invention, when opening a bottle can with a cap, it can control that a slip-out occurs.

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a schematic configuration of a cap shown as an embodiment of the present invention.
As shown in FIG. 1, the cap 10 is disposed on the top plate portion 11 and a cap main body including a peripheral wall portion 12 substantially hanging from the peripheral edge portion of the top plate portion 11, and the inner surface of the top plate portion 11. A liner 19 is provided.

  The peripheral wall portion 12 has a knurl 13 having a plurality of recesses formed in the upper portion on the top plate portion 11 side in the circumferential direction, and a groove continuously provided at the lower end of the knurled 13 and having a smaller diameter than the knurled portion 13. 14 and the lower end of the groove 14 and having a diameter larger than that of the groove 14, and a female screw formation scheduled portion 15 having a smooth surface and the lower end of the female screw formation scheduled portion 15 and the female screw formation. An easily breakable portion 16 having a diameter larger than the planned portion 15 and a flare (open end portion) 18 that is continuously provided at the lower end of the easily breakable portion 16 and gradually increases in diameter toward the lower side of the open end side are formed. Yes.

  A plurality of slit portions 17 extending in the circumferential direction and recessed inward in the radial direction are formed in the circumferential direction through the bridge 17a at the substantially central portion in the cap axis direction of the easy break portion 16, A slit 17b penetrating the peripheral wall portion 12 in the thickness direction is formed. The slit portion 17 has a rectangular shape defined by a pair of long sides extending in the circumferential direction and a pair of short sides extending in the cap axis direction when the peripheral wall portion 12 is viewed from the outside in the radial direction. A slit 17b is formed on the top plate portion 11 side of the pair of long sides extending in the circumferential direction.

  Moreover, the said recessed part of the knurl 13 consists of a pair of one side where the side view which looked at the peripheral wall part 12 from the radial direction outer side extended in the circumferential direction, and a pair of other side extended in a cap axial direction. The rectangular shape is defined. The knurl 13 is formed with a slit 13a penetrating in the thickness direction of the peripheral wall portion 12 on the side located on the top plate portion 11 side of the pair of one side extending in the circumferential direction.

  The cap body is formed of a rolled material made of, for example, aluminum or an aluminum alloy, preferably an AA (Alminum Association) 5000 series aluminum alloy, more preferably an AA5151 series aluminum alloy, and the liner 19 is made of, for example, polyethylene or polypropylene. Is formed of a resin composition containing as a main ingredient.

  Here, the hardness of the flare 18 is higher than the top plate part 11 by 10% or more and 18% or less. In the present embodiment, the cap body is formed of an AA5151-based aluminum alloy, and the flare 18 has a micro Vickers (Hv50g) hardness of 82 or more and 88 or less. For example, when the hardness of the top plate 11 is 74.5 in terms of micro Vickers (Hv50g) hardness and the hardness of the flare 18 is 10% higher than that, the hardness of the flare 18 is 82 in terms of micro Vickers (Hv50g) hardness. It becomes. Further, when the hardness of the top plate 11 is 74.5 in micro Vickers (Hv50g) hardness and the hardness of the flare 18 is 18% higher than that, the hardness of the flare 18 is 88 in micro Vickers (Hv50g) hardness. It becomes.

A method for screwing the cap 10 configured as described above to the cap portion 21 of the bottle can 20 will be described.
First, the lower surface of the liner 19 is brought into contact with the open end portion (curl portion) 21a of the base portion 21 to place the cap 10 on the base portion 21, and then the outer peripheral edge portion of the top plate portion 11 is moved downward in the can axis direction. A step portion 11a is formed on the outer peripheral edge portion, which gradually extends downward in the can axis direction as it goes outward in the radial direction. As a result, the outer peripheral edge of the liner 19 is also deformed so that its peripheral end face is directed downward in the can axis direction so as to follow the inner surface shape of the stepped portion 11a, thereby lowering the lower surface of the liner 19 to the opening end 21a. Closely contact the upper end surface and the outer peripheral surface.

  Furthermore, by maintaining the pressure at the time of forming the step portion 11a, by pressing the female screw formation scheduled portion 15 radially inward along the male screw portion 21b formed on the bottle can base portion 21, The female screw portion 15a is formed. Further, by pressing the flare 18 inward in the radial direction and causing the flare 18 to be caught in the bulging portion 21c connected to the lower end in the can axis direction of the male screw portion 21b of the bottle can base portion 21, the cap 10 can be A bottle can 22 with a cap screwed to the base 21 is obtained.

  In the bottle can 22 with a cap, when the cap 10 is rotated around the can axis in a direction in which the female screw portion 15a is loosened with respect to the male screw portion 21b of the bottle can 20, the cap 10 tends to move upward in the can axis direction. And At this time, since the flare 18 is wound around the bulging portion 21c of the bottle can base 21, the bulging portion 21c prevents the flare 18 from moving upward in the can axis direction, thereby easily breaking. The bridge 17a of the part 16 is broken. Thereafter, by further rotating the cap 10, the portion below the slit portion 17 of the cap 10 remains in the bulging portion 21c of the bottle can mouthpiece portion 21, and the portion above the slit portion 17 is moved upward in the can axis direction. By moving, the bottle can 22 with a cap is opened.

Next, a method for manufacturing the cap configured as described above will be described.
First, a cup-shaped cap body is obtained by drawing a circular plate (planar thickness 0.21 mm to 0.25 mm, outer diameter 65.0 mm to 65.8 mm) obtained by punching the rolled material. (Thickness 0.21 mm to 0.30 mm, outer diameter 38.2 mm to 38.8 mm, size 17.6 mm to 17.8 mm in the axial direction from the outer surface of the top plate portion to the open end of the peripheral wall portion) .

Next, a molding process is performed on the peripheral wall portion of the cap body. Here, first, a schematic configuration of an apparatus for forming the cap 10 by forming the peripheral wall portion of the cap body will be described.
As shown in FIGS. 3 and 4, the device 50 includes an inner tool 51 disposed inside the cap body W and an outer tool 52 disposed outside the cap body W.

The inner tool 51 is formed in a columnar shape, and an inner working portion that supports or presses the inner peripheral surface of the cap base body W outward in the radial direction is formed on the outer peripheral portion 51a.
The outer tool 52 is shaped so that its plan view forms a part of an annular body, and the outer tool 52 presses the outer peripheral surface of the cap body W radially inward to the outer peripheral portion 52a. The part is formed.

  In the above configuration, the inner tool 51 arranged inside the cap body W rotates around the axis O1, and the outer peripheral portion 52a is rotated around the arc center O2 of the outer peripheral portion 52a of the outer tool 52. By rotating along the axis, the cap body W rotates about the arc center O2 of the outer tool 52 along the outer peripheral portion 52a while rotating around the axis. Yes. In this process, the peripheral wall portion of the cap body W is sandwiched between the outer peripheral portions 51a and 52a of the tools 51 and 52, so that the peripheral wall portion is molded over the entire periphery. The cap 10 is formed.

  Here, in the outer peripheral portion 51a of the inner tool 51, a portion (hereinafter referred to as an “inner flare forming portion”) 51b that is subjected to molding processing on the open end portion of the peripheral wall portion of the cap body W is as shown in FIG. In the state where the peripheral wall portion of the cap body W is molded by the tools 51 and 52, the cap body W has an inclined shape that is gradually expanded in diameter from the top plate portion side toward the open end of the peripheral wall portion. ing.

  Further, a portion (hereinafter referred to as an “outer flare forming portion”) 52b of the outer peripheral portion 52a of the outer tool 52, which is subjected to molding processing on the open end portion of the peripheral wall portion of the cap body W, is shown in FIG. In a state in which the peripheral wall portion of the cap body W is molded by the tools 51 and 52, the cap body W has an inclined shape that is gradually reduced in diameter from the top plate portion side toward the open end side of the peripheral wall portion. ing.

  The inclination angle of the inner flare forming portion 51b and the outer flare forming portion 52b with respect to the axis line of each tool 51, 52 sandwiches the open end portion of the peripheral wall portion of the cap body W by the flare forming portions 51b, 52b. When the open end portion is formed in the flare 18 of the cap 10, the outer diameter of the flare 18 is set to be 0.3% to 1.0% larger than the outer diameter of the open end portion. .

Next, a method for forming the cap body W into the cap 10 by the apparatus 50 configured as described above will be described.
The inner tool 51 is disposed inside the cap body W and the outer tool 52 is disposed outside the cap body W, and then the inner tool 51 is rotated around the axis O1 in the direction of rotation R. By rotating, the cap body W is also moved in the same manner as the inner tool 51. Then, the peripheral wall portion of the cap body W extends along the outer peripheral portion 52a of the outer tool 52 along the entire periphery of the outer peripheral portion 52a from the rear end to the front end of the rotation direction R, and the outer periphery of the inner tool 51. The cap 10 is formed by forming the portion 51a. At this time, the open end portion of the peripheral wall portion of the cap body W is expanded in outer diameter by 0.3% to 1.0%, and the hardness is higher by 10% or more and 18% or less than the top plate portion 11. And formed into a flare 18.

  As described above, according to the cap 10 according to the present embodiment, the hardness of the flare 18 is higher by 10% or more and 18% or less than the top plate portion 11, and the hardness of the flare 18 of the present embodiment is micro Vickers ( Hv50g) Since the hardness is 82 or more and 88 or less, the flare 18 bulges even when a force directed upward in the can axis direction acts on the flare 18 when opening the bottle can 22 with a cap. It is possible to firmly lock the portion 21c.

  Therefore, when the plug is opened, the flare 18 is moved upward in the can axis direction while the inner peripheral surface of the flare 18 is expanded along the outer peripheral surface of the bulging portion 21c. It is possible to prevent the flare 18 from slipping out of the bulging portion 21c. As a result, the bridge 17a can be reliably broken at the time of opening, and the entire cap 10 including the flare 18 side can be prevented from being detached from the bottle can base part 22.

  Here, when the hardness of the flare 18 is greater than 88, when the flare 18 is wound around the bulging portion 21c and the cap 10 is screwed onto the bottle can base portion 21 (hereinafter referred to as "capping step"). , It becomes difficult to evenly wind the flare 18 over the entire circumference of the bulging portion 21c, and a portion of the flare 18 that is not engulfed in the bulging portion 21c may be formed depending on the position in the circumferential direction. And the slipping out easily occurs (hem winding processability).

  Similarly, when the hardness of the flare 18 is greater than 88, it becomes difficult to extend and deform in the axial direction so that the inner peripheral surface of the flare 18 is along the outer peripheral surface of the bulging portion 21c during the capping step. A high tensile force in the axial direction acts on the bridge 17a, and the bridge 17a is easily broken during the capping step (bridge breakage).

  In the present embodiment, a circular plate material obtained by punching a rolled material formed of an AA5151 series aluminum alloy (plate thickness 0.21 mm to 0.25 mm, outer diameter 65.0 mm to 65.8 mm). ), And cup-shaped cap body W (thickness 0.21 mm to 0.30 mm, outer diameter 38.2 mm to 38.8 mm, axial direction from the outer surface of the top plate portion to the open end of the peripheral wall portion) 17.6 mm to 17.8 mm), and then the outer diameter of the open end of the peripheral wall portion of the cap body W is expanded by 0.3% to 1.0% to form the flare 18. Therefore, the flare 18 whose hardness is higher by 10% or more and 18% or less than the top plate portion 11 can be formed reliably.

  Furthermore, the cap 10 of the present embodiment is formed of an AA5000 series aluminum alloy as a commonly used cap material, and the flare 18 is formed by increasing the diameter of the open end portion of the cap body W, and the hardness thereof. The cap 10 can be formed without increasing the cost. That is, if the cap is formed of a rolled material having high hardness, the flare 18 also has high hardness. However, since such a material is generally expensive, an increase in the cost of the cap cannot be avoided.

  Next, as a specific example of the above embodiment, the results of measuring the micro Vickers (Hv50g) hardness of each part after forming the cap 10 are shown in FIG. As a comparative example, a cap formed with a flare without increasing the outer diameter of the open end portion of the peripheral wall portion of the cap body W was employed. The cap bodies W for forming the caps of these examples and comparative examples are the same, and the cap body W is formed of an AA5151 series aluminum alloy, and has a thickness of about 0.26 mm. The diameter is about 38.4 mm, the size in the axial direction from the outer surface of the top plate portion to the open end of the peripheral wall portion is about 17.7 mm, and the plate thickness is about a circular shape in plan view obtained by punching the rolled material It is formed by drawing a plate material having a diameter of 0.25 mm and an outer diameter of about 65.5 mm. And about the cap 10 of the Example, the outer diameter of the open end part in the surrounding wall part of the cap base body W was expanded about 0.5%, and the flare 18 was formed. As a result, as shown in FIG. 5, it was confirmed that the hardness of the flare 18 can be improved by about 11% than the hardness of the top plate portion 11.

  Next, the verification test about the above effect was implemented. The results are shown in FIG. In this figure, the diameter expansion rate is the difference between the outer diameter of the open end and the outer diameter of the flare 18 when the open end of the peripheral wall portion of the cap body W is formed in the flare 18. It is the value divided by the outer diameter of the part. The cap with the flare hardness of 75 is obtained without increasing the outer diameter of the open end of the peripheral wall of the cap body W. Further, the skirt winding workability shown in FIG. 6 indicates whether or not the flare 18 can be uniformly wound around the bulging portion 21c over the entire circumference. It indicates whether or not the bridge is broken during the capping step.

  As a result, when the hardness of the flare 18 is 10% or more and 18% or less higher than the top plate portion 11 and the micro Vickers (Hv50g) hardness is 82 or more and 88 or less, suppression of slipping off and good skirts are achieved. It was confirmed that winding workability and prevention of bridge breakage could be realized.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  When the bottle can with cap is opened, it is possible to suppress the occurrence of so-called slip-out.

The partially broken side view of the cap shown as one Embodiment which concerns on this invention is shown. It is a partially expanded sectional view which shows the state which screwed the cap shown in FIG. 1 to the nozzle | cap | die part of a bottle can. It is a top view which shows schematic structure of the manufacturing apparatus of the cap shown as one Embodiment which concerns on this invention. FIG. 4 is a cross-sectional view of the cap manufacturing apparatus shown in FIG. 3 when cut in the axial direction of the cap element, the inner tool, and the outer tool. It is a figure which shows the hardness of each part of the cap shown as one Embodiment which concerns on this invention, and a prior art example. It is a figure which shows the result of having evaluated the tail omission, skirt winding workability, and bridge | bridging of the cap shown as one Embodiment which concerns on this invention, and a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cap 11 Top plate part 12 Peripheral wall part 16 Breakable part 17 Slit part 17a Bridge 17b Slit 18 Flare (open end part)
19 liner 20 bottle can 21 cap part 21b male thread part 21c bulge part

Claims (2)

A cap body having a top plate portion and a peripheral wall portion substantially hanging from the peripheral edge portion of the top plate portion; and a liner disposed on the inner surface of the top plate portion. A slit portion that extends in the direction and is recessed inward in the radial direction is provided with an easily breakable portion formed in the circumferential direction via a bridge, and the slit portion is formed with a slit that penetrates the peripheral wall portion in the thickness direction. The peripheral wall portion is screwed into a male screw portion formed in the mouthpiece portion of the bottle can, and the open end portion of the peripheral wall portion is wound into a bulging portion that is connected to the lower end in the can axis direction of the male screw portion. A cap that is screwed onto the base of the bottle can,
The cap having the open end portion made harder by 10% or more and 18% or less than the top plate portion. The cap according to claim 1, wherein
The cap, wherein the open end is 82 or more in micro Vickers (Hv50g) hardness.

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