JP4342988B2 - Bottle can body manufacturing apparatus and bottle can body manufacturing method - Google Patents

Description

  The present invention relates to a bottle can body having a male thread formation planned portion and a skirt formation planned portion continuously provided at a lower end of the male screw formation planned portion and bulging radially outward. The manufacturing apparatus of the bottle can body which forms a part, the manufacturing method of a bottle can body, and a bottle can.

In general, a bottle can filled with a soft drink or the like is formed as follows.
First, a metal plate made of pure Al or an Al alloy is drawn and ironed to form a bottomed cylindrical body 1 (FIG. 7A), and then a neck-in is formed in the opening of the cylindrical body 1. The shoulder portion 3 which is processed and is connected to the upper end of the barrel portion 2 and the upper end of the barrel portion 2 and gradually extends inward in the radial direction as it goes upward in the can axis direction. A bottle can body 5 is formed which is provided continuously with the upper end and includes a base portion 4 extending upward in the can axis direction (FIG. 7B).

  And after expanding the diameter of the part excluding the lower part 4a of the cap part 4 of the bottle can body 5 (FIG. 7 (c)), the diameter-enlarged part is sequentially processed upward in the can axis direction. The bottle can body 5 shown in FIG. 7 (d) is formed by shifting the position and reducing the diameter.

The base part 4 of the bottle can body 5 formed in this way has a skirt formation planned part 4b continuously provided at the upper end in the can axis direction of the base part lower part 4a and bulging radially outward, and this skirt formation planned part. A male screw formation scheduled portion 4c provided continuously with the upper end of 4b and extending upward in the can axis direction, and a curl portion formed continuously with the upper end of the male screw formation planned portion 4c and having a smaller diameter than the planned formation portion 4c. 4d. The upper end portion in the can axis direction of the base portion lower portion 4a is a neck portion formation planned portion 4e having a smaller diameter than the skirt formation planned portion 4b.
After that, as shown in FIG. 8, the male screw portion 6 is formed on the male screw formation scheduled portion 4 c of the base portion 4 of the bottle can body 5, and the skirt portion 7 is formed on the skirt formation planned portion 4 b.

Among these, there is an apparatus and method for forming the male screw portion 6 disclosed in the following Patent Document 1, but in a bottle can with a cap in which a cap is screwed to a cap portion of the bottle can, In order to ensure the sealing performance of the contents, it is necessary to form the skirt portion 7.
It is known that the male screw portion 6 and the skirt portion 7 are generally formed by the apparatus shown in FIGS.
The device 100 is arranged inside and outside the bottle can body cap part 4, and is provided with a screw forming piece 101 for forming the male screw part 6 in the male screw forming scheduled part 4 c, and the screw forming piece 101 below the can axis direction. And a skirt forming piece 102 which is arranged inside and outside the base part 4 and which forms the skirt part 7 in the skirt formation scheduled part 4b.

The screw forming piece 101 includes an inner screw forming piece 101a arranged on the inner side of the bottle can body base portion 4 and an outer screw forming piece 101b arranged on the outer side, and the skirt forming piece 102 is similarly arranged on the inner skirt. A forming piece 102a and an outer skirt forming piece 102b are provided. Among these, the inner screw forming piece 101a and the inner skirt forming piece 102a are rotatably supported on the same axis and supported to be movable in the radial direction of the bottle can body 5, and the outer screw forming piece 101b and The outer skirt molding piece 102b has the same configuration.
Here, the apparatus 100 having the screw forming piece 101 and the skirt forming piece 102 is supported so as to be rotatable with respect to a rotation axis substantially coincident with the can axis of the bottle can body 5 arranged in the apparatus 100. It has become.

When the male screw portion 6 and the skirt portion 7 are formed, the device 100 configured in this manner holds the male screw formation scheduled portion 4c of the bottle can body 5 by the screw forming pieces 101a and 101b. The entire device 100 is rotationally driven around the rotation axis, whereby the male screw portion 6 is formed in the bottle can body 5.
At this time, the inner skirt forming piece 102a presses the inner peripheral surface of the skirt formation scheduled portion 4b of the bottle can body 5 radially outward by the outermost peripheral portion 102c, and the outer skirt forming piece 102b A portion below the outermost peripheral portion 102c of the molding piece 102a in the can axis direction, that is, an outer peripheral surface of the neck portion forming planned portion 4e connected to the lower end in the can shaft direction of the skirt forming planned portion 4b is pressed radially inward. Thus, the skirt portion 7 is also formed simultaneously with the male screw portion 6.
JP 2002-066664 A

  By the way, according to the conventional bottle can manufacturing apparatus and manufacturing method, in the above-described forming process, the screw forming portion lower portion 101c of the outer screw forming piece 101b and the outermost peripheral portion 102c of the inner skirt forming piece 102a The distance C in the can axis direction increases sequentially as shown in FIG. That is, at the beginning of the molding process, the distance C is minimized as shown in FIG. 10A, and at this time, the circumferential position A of the bottle can body 5 shown in FIG. Thereafter, as the device 100 is driven to rotate and the male screw portion 6 and the skirt portion 7 are formed, the distance C gradually increases, and at the end of the processing, the distance C is as shown in FIG. At this time, the circumferential position B of the bottle can 5 shown in FIG. 8 is formed.

  Therefore, when the outer skirt forming piece 102b presses the inner peripheral surface of the skirt formation scheduled portion 4b of the bottle can body 5 radially outward to form the skirt portion 7, at the circumferential position A, the distance C Therefore, even if the screw forming piece 101 and the skirt forming piece 102 are separated from the bottle can body mouthpiece 4 after this pressing, the pushing amount can be substantially maintained, but the circumferential position B In this case, since the distance C is the maximum, when the molding pieces 101 and 102 are separated from the bottle can body cap part 4 after the pressing, a so-called springback occurs, and the pushing amount cannot be maintained. In some cases, the radius of curvature R and the skirt angle θ of the skirt portion 7 in the vicinity of the circumferential position B are larger than those of the other portions.

  In a bottle can with a cap in which a cap is screwed onto a bottle can that has been subjected to a predetermined process on such a bottle can body 5, a cap bridge disposed on the skirt portion 7 of the bottle can when the cap is loosened. There was a problem that the cap could not be broken and the cap flare was opened in an expanded state. Therefore, there is a problem that it becomes difficult to reseal the bottle can again.

  The present invention has been made in consideration of such circumstances, and can form a skirt portion positioned below the male screw portion formed in the base portion in the can axis direction with high accuracy. A bottle can body manufacturing apparatus, a bottle can body manufacturing method, and a bottle can capable of satisfactorily opening and resealing a cap with a cap screwed on a bottle can subjected to a predetermined processing The purpose is to provide.

In order to solve the above-described problems and achieve such an object, the present invention proposes the following means.
The invention according to claim 1 is a bottle can body provided with a male screw formation scheduled portion and a skirt formation planned portion that is continuously provided at the lower end of the male screw formation planned portion and bulges outward in the radial direction. A bottle can manufacturing apparatus for forming a male screw part and a skirt part, the screw forming piece being arranged inside and outside the base part and forming a male screw part in the male screw forming scheduled part, and the screw forming The screw forming piece and the skirt molding are provided with a skirt forming piece that is disposed below and in the can axis direction of the piece and that is respectively disposed inside and outside the base part and that forms a skirt part in the skirt formation scheduled part. An inner skirt forming piece disposed on the inner side of the base portion, the restraining portion for restraining the upper portion in the can axis direction of the skirt forming scheduled portion located between the piece and the can axis direction. With The inner skirt forming piece includes an outermost peripheral portion that presses the inner peripheral surface of the lower portion in the can axis direction of the skirt formation scheduled portion radially outward, and between the screw forming piece and the skirt forming piece, A groove forming piece provided with a pressing portion that presses the outer peripheral surface of the upper portion in the can axis direction of the skirt formation scheduled portion radially inward and forms a groove portion extending in the circumferential direction is provided, and the inner skirt forming piece The distance in the can axis direction between the outermost peripheral portion and the pressing portion of the groove forming piece is substantially constant along the circumferential direction of the bottle can body .

According to the bottle can body manufacturing apparatus according to the present invention, when the male thread portion and the skirt portion are formed in the bottle can body base portion, the upper portion in the can axis direction of the skirt formation scheduled portion can be restrained by the restraining portion. Thus, the skirt portion can be formed with high accuracy.
Further, since the groove forming piece is provided, the width of the skirt portion in the can axis direction differs depending on the circumferential position of the bottle can body, depending on the screw winding shape of the male screw portion formed in the base portion. Regardless, the shape retaining property of the skirt portion formed by the outermost peripheral portion can be made substantially constant with respect to the circumferential direction of the bottle can body, and a highly accurate skirt portion can be formed. Furthermore, the groove forming piece improves the close contact force between the inner peripheral surface of the lower part in the can axis direction of the skirt formation planned portion and the outermost peripheral portion of the inner skirt forming piece, and ensures a highly accurate skirt portion. Can be formed.

The invention according to claim 2 is a bottle can body provided with a male screw formation scheduled portion and a skirt formation planned portion swelled radially outwardly connected to the lower end of the male screw formation planned portion in the base portion. A method for manufacturing a bottle can body that forms a male screw portion and a skirt portion, wherein the male screw portion is formed in the male screw formation scheduled portion by means of screw forming pieces respectively arranged on the inner side and the outer side of the base portion, and When the skirt portion is formed in the skirt formation planned portion by the skirt forming pieces disposed below the screw forming piece in the can axis direction and on the inside and outside of the base portion, The upper part in the can axis direction of the skirt formation planned portion located between the skirt forming piece and the can axis direction is constrained , and the skirt forming piece is arranged on the inner side of the base part. The inner skirt forming piece includes an outermost peripheral portion that presses the inner peripheral surface of the lower portion in the can axis direction of the skirt formation planned portion radially outwardly, and is between the screw forming piece and the skirt forming piece. A groove forming piece provided with a pressing portion that presses the outer peripheral surface of the upper part in the can axis direction of the skirt formation scheduled portion radially inward and forms a groove portion extending in the circumferential direction,
When forming the male thread portion and the skirt portion, the distance in the can axis direction between the outermost peripheral portion of the inner skirt forming piece and the pressing portion of the groove forming piece is substantially constant along the circumferential direction of the bottle can body. It is characterized by .

According to the manufacturing how the manufacturing apparatus and the bottle can member of the bottle can member according to the present invention, when forming the male screw portion and the skirt portion to the bottle can member mouthpiece, restraining the can axis direction upper portion of said skirt forming scheduled portion Since it is restrained by the portion, the skirt portion can be formed with high accuracy in the skirt formation scheduled portion.

Embodiments of the present invention will be described below with reference to the drawings.
1 to 3 show a schematic configuration of the bottle can body manufacturing apparatus shown as the first embodiment of the present invention.
Since the bottle can body used in this bottle can body manufacturing apparatus is the same as the conventional one shown in FIGS. 7 and 8, the description thereof will be omitted, and the same parts shown in these drawings will be denoted by the same reference numerals. Will be described below.

  The bottle can body manufacturing apparatus 10 includes an inner molding piece 60 disposed on the inner side of the bottle can body base portion 4 and an outer molding piece 50 disposed on the outer side, and the can shafts of these molding pieces 50 and 60. The upper part in the direction is the screw forming part 11, and the lower part in the can axis direction is the skirt forming part 12. In other words, a screw forming piece 11 that is arranged inside and outside the bottle can body base part 4 and that forms the male screw part 6 on the male screw forming scheduled part 4c, and is arranged below the screw forming piece 11 in the can axis direction. And a skirt forming piece 12 that is disposed inside and outside the base portion 4 and that forms the skirt portion 7 in the skirt formation scheduled portion 4b.

The screw forming piece 11 includes an inner screw forming piece 11a disposed inside the bottle can body mouthpiece 4 and an outer screw forming piece 11b disposed outside. Similarly, the skirt forming piece 12 includes an inner skirt forming piece 12a and an outer skirt forming piece 12b.
The inner screw forming piece 11a and the inner skirt forming piece 12a, and the outer screw forming piece 11b and the outer skirt forming piece 12b are supported so as to be rotatable coaxially and movably in the radial direction. Yes.

Here, as shown in FIG. 3, the inner skirt forming piece 12 a is a first member that presses the inner peripheral surface of the lower portion in the can axis direction of the skirt formation scheduled portion 4 b of the bottle can body 5 outwardly in the radial direction. The outer skirt forming piece 12b is provided with an outer peripheral surface of a portion (neck forming planned portion 4e) connected to the lower end of the skirt forming planned portion 4b of the bottle can body 5 at a lower portion of the outer skirt forming piece 12b. A second pressing portion 14 is provided for pressing to. The first and second pressing portions 13 and 14 are formed on the outer surfaces of the molding pieces 12a and 12b with substantially the same cross-sectional shape over the entire circumference, and the rotation axis direction of the molding pieces 12a and 12b. Are formed at substantially the same height.
With the skirt molding piece 12 configured in this manner, the inner peripheral surface located above the lower end portion 7a of the skirt portion 7 to be formed is pressed by the first pressing portion 13 from the lower end portion 7a. The skirt portion 7 is formed by pressing the outer peripheral surface located in the lower direction by the second pressing portion 14.

  In addition, concave and convex screw forming portions 15 and 16 are formed on the outer peripheral surfaces of the inner screw forming piece 11a and the outer screw forming piece 11b in a spiral shape and in a shape corresponding to each other. Furthermore, the outer peripheral surface of the lower end portion 17 of the inner screw forming piece 11a is substantially the same as the inner surface shape of the upper portion in the can axis direction of the skirt portion 7 to be formed, and as shown in FIG. When the male thread portion 6 is formed by the screw forming piece 11b, at the same time, the inner peripheral surface of the upper portion in the can axis direction of the skirt formation scheduled portion 4b of the bottle can body 5 can be pressed by the lower end portion 17. That is, in other words, the sub-skirt forming piece that presses the inner peripheral surface of the upper portion in the can axis direction of the skirt forming portion 4b radially outward between the screw forming piece 11 and the skirt forming piece 12 in the can axis direction. 17 is provided.

  The sub-skirt forming piece 17 is set so that the lower end position in the can axis direction is unchanged over the entire circumference so as to match the inner peripheral surface shape of the skirt portion 7 to be formed, and the upper end is the rotational axis of the inner screw forming piece 11a. The width in the can axis direction is changed so as to gradually move away from or approach the lower end that is not changed.

The bottle can body manufacturing apparatus 10 configured as described above is supported so as to be rotatable around a rotation axis O substantially coincident with the can axis of the bottle can body 5 arranged, and can be moved back and forth in the direction of the rotation axis O. When the apparatus 10 is driven forward, the screw forming piece 11 and the skirt forming piece 12 are arranged inside and outside the bottle can body mouthpiece 4 as shown in FIGS. It has become so.
In addition, the bottom part of the bottle can body 5 is hold | maintained on the holding table which is not shown in figure so that the nozzle | cap | die part 4 may face the manufacturing apparatus 10 of a bottle can body.

  A method of forming the male screw part 6 and the skirt part 7 in the bottle can body cap part 4 by the bottle can body manufacturing apparatus 10 configured as described above will be described.

  First, after holding the bottle can 5 on the holding table, the apparatus 10 is driven forward in the direction of the rotation axis O. At this time, the screw forming piece 11 and the skirt forming piece 12 stand by at their respective standby positions, and among these, the inner screw forming piece 11a and the inner skirt forming piece 12a have their rotational axes aligned with those of the apparatus 10. Since it substantially coincides with the rotational axis O, the inner screw forming piece 11a and the inner skirt forming piece 12a are inserted and arranged inside the bottle can body mouthpiece part 4, and the outer screw forming piece 11b is placed outside the mouthpiece part 4. And the outer skirt forming piece 12b is arranged.

  Thereafter, the inner screw forming piece 11a and the outer screw forming piece 11b are driven to move toward each other by a driving means (not shown), and the inner skirt forming piece 12a and the outer skirt forming piece 12b are moved closer to each other. Driven by movement. As a result, as shown in FIGS. 2 and 3, the male thread formation scheduled portion 4c of the base portion 4 is held by the screw forming piece 11, and the inner peripheral surface of the skirt formation planned portion 4b at the lower portion in the can axis direction is The outer peripheral surface of the portion (neck formation planned portion 4e) that is pressed radially outward by the inner skirt forming piece 12a and is connected to the lower end in the can axis direction of the skirt forming planned portion 4b is radially inward by the outer skirt forming piece 12b. Further, the inner peripheral surface of the upper part in the can axis direction of the skirt formation planned portion 4b positioned between the screw forming piece 11 and the skirt forming piece 12 in the can axis direction is radially outward by the sub skirt forming piece 17. It will be pushed toward.

  In this state, when the apparatus 10 is rotationally driven around the rotation axis O, the male screw portion 6 and the skirt portion 7 are formed over the entire circumference of the base portion 4 of the bottle can body 5. In this molding process, the auxiliary skirt molding piece 17 presses the inner peripheral surface of the upper part in the can axis direction of the skirt formation planned portion 4b, and the upper part in the can axis direction of the skirt part 7 extends over the entire circumference of the auxiliary skirt. Press molding is performed by the molding piece 17.

  As described above, according to the bottle can body manufacturing apparatus and method according to the present embodiment, in the process of forming the male screw portion 6 and the skirt portion 7, the can axis direction of the skirt formation scheduled portion 4 b of the bottle can body 5. Since the upper inner peripheral surface is pressed radially outward by the sub-skirt forming piece 17, the width in the can axis direction of the skirt portion 7 is different depending on the circumferential position of the bottle can body 5. The skirt portion 7 can be formed with substantially the same dimensional accuracy over the entire circumference, and the highly accurate skirt portion 7 can be formed.

  This makes it possible to form the curvature radius R and the skirt angle θ at the lower part of the skirt portion 7 shown in FIG. 8 with appropriate dimensions over the entire circumference of the bottle can body 5. When a cap is screwed to a bottle can that has been subjected to a predetermined process, when the cap is loosened, the bridge of the cap can be reliably broken. Occurrence of problems with the stopper and reseal can be suppressed.

  The evaluation test about the manufacturing apparatus and manufacturing method of the bottle can body which concerns on this embodiment was implemented. As an evaluation method, for each of the ten bottle can bodies 5 formed by the manufacturing apparatus 10, the skirt angle θ (see FIG. 8) was measured at three locations in the skirt portion 7 at arbitrarily different circumferential positions. . As a comparative example, a skirt angle θ was measured in the same manner using a bottle can body formed by the manufacturing apparatus 100 shown in FIG. As a result, in the comparative example, the difference between the maximum value and the minimum value (hereinafter simply referred to as “R”) was 11.42 ° and the standard deviation was 3.398, whereas the difference according to the present embodiment was described above. In the bottle can body 5 formed by the manufacturing apparatus 10, R was 6.93 ° and the standard deviation was 1.971. Thereby, the above-described operation and effect of the apparatus and method according to the present embodiment could be verified.

Next, although 2nd embodiment of this invention is described, the same code | symbol is attached | subjected to the site | part similar to above-mentioned 1st embodiment, and the description is abbreviate | omitted.
The bottle can body manufacturing apparatus 20 according to the second embodiment includes a screw forming piece 21 and a skirt forming piece 22 disposed below the screw forming piece 21 in the can axial direction, as shown in FIG. The screw forming piece 21 includes an inner screw forming piece 21a and an outer screw forming piece 11b, and the skirt forming piece 22 includes an inner skirt forming piece 12a and an outer skirt forming piece 22b. Of these, the inner screw forming piece 21a is the same as the conventional structure in which the sub-skirt forming piece 17 is removed from the structure shown in the first embodiment, so that the description thereof is omitted.

  In addition to the configuration of the first embodiment, the outer skirt forming piece 22b presses the outer peripheral surface of the upper portion in the can axis direction of the skirt formation scheduled portion 4b of the bottle can body 5 inward in the radial direction on the upper portion in the can axis direction. The third pressing portion 23 is provided. That is, a third pressing portion 23 is provided between the first pressing portion 13 as the outermost peripheral portion of the inner skirt forming piece 12a and the screw forming piece 21 in the can axis direction.

  The third pressing portion 23 is formed so as to be positioned above the first pressing portion 13 of the inner skirt forming piece 12a in the can axis direction and to be positioned below the screw forming piece 21 in the can axis direction. . And this 3rd press part 23 is formed with the substantially same cross-sectional shape over the perimeter over the outer peripheral surface of outer skirt forming piece 22b similarly to the 1st and 2nd press parts 13 and 14. The molding pieces 22b are formed at substantially the same height in the rotation axis direction. With this configuration, the distance in the can axis direction between the first pressing portion 13 of the inner skirt forming piece 12a and the third pressing portion 23 of the outer skirt forming piece 22b is substantially constant over the entire circumference of the bottle can body 5. Will be. In other words, the first pressing portion 13 and the third pressing portion 23 as the first portion that is positioned above the pressing portion 13 in the can axis direction and presses the outer peripheral surface of the base portion 4 radially inward. The distance in the can axis direction is substantially constant over the entire circumference of the bottle can body 5.

With the above configuration, when the male thread portion 6 and the skirt portion 7 are formed in the bottle can body base portion 4, the inner skirt forming piece 12a presses the inner peripheral surface of the lower portion in the can axis direction of the skirt formation scheduled portion 4b radially outward. At the same time, the outer skirt forming piece 22b presses the outer peripheral surface of the portion connected to the lower end of the skirt formation scheduled portion 4b radially inward, whereby the skirt portion 7 is formed. At the same time, the third pressing portion 23 of the outer skirt forming piece 22b presses the outer peripheral surface of the upper portion in the can axis direction of the skirt formation scheduled portion 4b inward in the radial direction, as shown in FIG. In addition, the bottle can body 5 is formed which is recessed radially inwardly on the upper outer peripheral surface in the can axis direction of the skirt portion 7 and in which the groove portion 24 extending in the circumferential direction is formed. That is, the third pressing portion 23 acts as a groove forming piece 23 that forms the groove 24 on the outer peripheral surface of the skirt portion 7 in the can axis direction. In other words, the third pressing portion 23 and the skirt forming piece 21 and the skirt A groove forming piece 23 is disposed between the forming piece 22 and the can axis direction.
In the bottle can body 5 formed in this way, after the opening end is bent radially outward to form the curled portion 25, the outer surface of the curled portion 25 is crushed radially inward. Slot processing is performed to form a bottle can 26.

As described above, according to the bottle can body manufacturing apparatus and method according to the present embodiment, since the outer skirt forming piece 22b includes the groove forming piece 23, the first pressing portion 13 of the inner skirt forming piece 12a. And the distance in the can axis direction from the first portion that is located above the pressing portion 13 in the can axis direction and presses the outer peripheral surface of the base portion 4 inward in the radial direction is substantially constant over the entire circumference of the bottle can body 5. Can be.
Therefore, depending on the winding shape of the male thread portion 6 to be formed, the skirt portion formed by the first pressing portion 13, although the width in the can axis direction of the skirt portion 7 varies depending on the circumferential position of the bottle can body 5. 7 can be made substantially constant over the entire circumference of the bottle can body 5, and the occurrence of defective molding of the skirt portion 7 can be suppressed.

That is, as shown in FIG. 9, in the conventional configuration without the groove forming piece 23, the first pressing portion 102c (13) and the pressing portion 102c (13) are positioned above the can axis direction. The distance C in the can axis direction from the first portion that presses the outer peripheral surface of the base portion 4 radially inward, that is, the lower end 101c of the screw forming portion of the outer screw forming piece 101b (11b) is When the distance C is small, the shape retainability of the molding of the skirt portion 7 by the first pressing portion 102c (13) can be satisfactorily achieved while the distance C is different. When is large, so-called springback is likely to occur, and it becomes difficult to achieve good shape retention.
However, since the bottle can manufacturing apparatus 20 according to the present embodiment includes the groove forming piece 23, the distance can be made substantially constant over the entire circumference of the bottle can 5, and a good shape can be maintained. The property can be realized over the entire circumference of the can 5.
Furthermore, the groove forming piece 23 improves the close contact force between the inner peripheral surface of the skirt formation scheduled portion 4b in the can axis direction lower portion and the first pressing portion 13 of the inner skirt forming piece 12a, and is highly accurate. The skirt portion 7 can be reliably formed.
Further, in the bottle can body 5 formed in this way, since the groove portion 24 extending in the circumferential direction is formed in the upper portion of the skirt portion 7 in the can axis direction, as shown in FIG. Of the inner peripheral surface of the cap 40 that is screwed into the cap portion 4, the portion of the bottle can 26 that faces the groove portion 24 has a shape that corresponds to the groove shape of the groove portion 24 and is smaller than the groove portion 24. By forming the protrusion 40a, the opening and closing state of the can can be accurately grasped by the sound and response when the protrusion 40a of the cap 40 enters and exits from the groove 24 of the bottle can 26 at the time of opening and closing. Is possible. Also, once the cap is opened, the cap 40 is recapped, and then when the can is carried, for example, if the protrusion 40a of the cap 40 is located in the groove 24 of the bottle can 26, the screwing of the cap 40 is loosened. Can be prevented. Furthermore, even when the can internal pressure rises excessively, the cap 40 can be prevented from coming off the bottle can base 4.

Next, a third embodiment according to the present invention will be described.
As shown in FIG. 6, the bottle can manufacturing apparatus 30 according to the present embodiment includes a screw forming piece 31 and a skirt forming piece 32 disposed below the screw forming piece 31 in the can axis direction. The screw forming piece 31 includes an inner screw forming piece 31a and an outer screw forming piece 31b, and the skirt forming piece 32 has a schematic configuration including an inner skirt forming piece 32a and an outer screw forming piece 32b. ing. Since the screw forming piece 31 has substantially the same configuration as that of the second embodiment shown in FIG.

The inner skirt forming piece 32a includes a first pressing portion (first convex portion) 13 that presses the inner peripheral surface of the skirt formation planned portion 4b in the can axis direction lower portion radially outward, and the first pressing portion 13. The first recess 34 is provided at the lower end in the can axis direction.
Here, the outer peripheral surface of the upper end portion 35 in the can axis direction of the inner skirt forming piece 32a connected to the upper end in the can axis direction of the first pressing portion 13 is the inner surface shape of the upper portion in the can axis direction of the skirt portion 7 to be formed. As shown in FIG. 6, when the male screw part 6 and the skirt part 7 are formed on the bottle can body 5 by the molding pieces 31 and 32 as shown in FIG. The inner peripheral surface of the upper part in the can axis direction of the skirt formation scheduled portion 4b can be pressed by the outer peripheral surface of the upper end portion 35. That is, in other words, the sub-skirt forming piece that presses the inner peripheral surface of the upper portion in the can axis direction of the skirt forming portion 4b radially outward between the screw forming piece 31 and the skirt forming piece 32 in the can axis direction. 35 is provided.
The upper end 35 and the first recess 34 of the molding piece 32a are formed on the outer surface of the piece 32a with substantially the same cross-sectional shape over the entire circumference, and are substantially the same in the rotation axis direction of the piece 32a. They are formed at the same height position.

  The outer skirt forming piece 32b is a second pressing portion (second convex portion) 14 that presses the outer peripheral surface of the neck portion forming planned portion 4e provided continuously with the lower end in the can axis direction of the skirt forming planned portion 4b inward in the radial direction. And a second recess 36 having an outer peripheral surface substantially the same as the outer surface shape of the lower portion in the can axis direction of the skirt portion 7 to be formed.

  When the bottle can body 5 is arranged in the bottle can body manufacturing apparatus 30 configured as described above, the first pressing portion 13 of the inner skirt forming piece 32a and the outer skirt forming piece as shown in FIG. A second recess 36 of 32b is disposed opposite to the lower part in the can axis direction of the skirt formation scheduled portion 4b, and the first depression 34 of the inner skirt forming piece 32a and the second pressing of the outer skirt forming piece 32b The portion 14 is disposed to face the neck portion formation scheduled portion 4e.

  In this state, when the inner and outer skirt forming pieces 32a and 32b are moved in the direction in which they approach each other, the first pressing portion 13 of the inner skirt forming piece 32a passes through the lower part in the can axis direction of the skirt forming scheduled portion 4b. Thus, the second recess 36 of the outer skirt forming piece 32b is pressed. At the same time, the second pressing portion 14 of the outer skirt forming piece 32b presses the first concave portion 34 of the inner skirt forming piece 32a through the neck portion forming scheduled portion 4e.

  Thereafter, in the same manner as in each of the embodiments described above, by rotating the screw forming piece 31 and the skirt forming piece 32 around the can axis of the bottle can body 5, the male screw portion 6 and the A skirt portion 7 is formed.

  As described above, according to the bottle can body manufacturing apparatus and method according to the present embodiment, the inner skirt forming piece 32 a includes the first pressing portion 13, and the outer skirt forming piece 32 b includes the second recess 36. Therefore, when the skirt portion 7 is formed, it is possible to press-mold not only the inner peripheral surface of the skirt formation scheduled portion 4b but also the outer peripheral surface at the lower portion in the can axis direction. Accordingly, it is possible to realize further higher accuracy of the radius of curvature of the skirt portion 7 to be molded and the skirt angle.

  Further, since the inner skirt forming piece 32a includes the first concave portion 34 and the outer skirt forming piece 32b includes the second pressing portion 14, when the skirt portion 7 is formed, the inner peripheral surface of the neck portion formation planned portion 4e. It is possible to press both the outer peripheral surface and the outer peripheral surface. Therefore, in the formed bottle can, the neck portion connected to the lower end in the can axis direction of the skirt portion 7 can be formed with high accuracy, and thereby, the neck portion can be connected to the upper end portion in the can axis direction. It is possible to form the skirt portion 7, particularly the lower portion of the skirt portion 7 in the can axis direction with high accuracy. By the above, the curvature radius of the skirt part 7 formed and the further high precision of a skirt angle can be implement | achieved reliably.

The evaluation test about the manufacturing apparatus and manufacturing method of the bottle can body which concerns on this embodiment was implemented. The evaluation method and the comparative example were the same as those in the above embodiment.
As a result, in the comparative example, as described above, R was 11.42 ° and the standard deviation was 3.398, whereas in the bottle can body 5 formed by the manufacturing apparatus 30, R was 6. It was 36 ° and the standard deviation was 1.487. Thereby, the above-described operation and effect of the apparatus and method according to the present embodiment could be verified.

  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. For example, in the said 2nd embodiment, although the structure which formed the groove part 24 over the perimeter of the bottle can body 5 was shown, not only a perimeter but a part in the circumferential direction may be sufficient.

  In the first embodiment, the sub skirt forming piece 17 is formed at the lower end of the inner screw forming piece 11a in the can axis direction. In the third embodiment, the sub skirt forming piece 35 is formed in the can of the inner skirt forming piece 32a. Although the structure formed in the axial direction upper end part was shown, respectively, it is good not only as these but the subskirt shaping | molding pieces 17 and 34 may be separate parts from each said shaping | molding piece 11a and 32a.

Further, in the third embodiment, when the male screw portion 6 and the skirt portion 7 are molded, the inner peripheral surface is radially outwardly supported in a state where the outer peripheral surface of the lower portion in the can axis direction of the skirt formation scheduled portion 4b is supported. In the state where the inner peripheral surface of the neck portion formation planned portion 4e is supported while the outer peripheral surface is pressed radially inward, the outer periphery of the skirt formation planned portion 4b is not limited thereto. You may implement at least one of the said support of a surface, or the said support of the internal peripheral surface of the neck part formation scheduled part 4e.
In each of the above embodiments, the outer screw forming piece 11b and the outer skirt forming piece 12b ... are shown as an integrated outer forming piece 50, and the inner screw forming piece 11a ... and the inner skirt forming piece 12a. .. Are shown as the inner forming piece 60 integrated with each other, but the screw forming pieces 11b... And the skirt forming pieces 12b.

  A bottle can with a cap in which a skirt portion located below a male screw portion formed in a base portion can be formed with high precision, and a cap is screwed to a bottle can that has been subjected to predetermined processing on the bottle can body The present invention provides a bottle can body manufacturing apparatus, a bottle can body manufacturing method, and a bottle can that can be successfully opened and resealed.

It is a schematic side view which shows the manufacturing apparatus of the bottle can shown as one Embodiment of this invention, Comprising: It is a figure which shows the state before a bottle can is arrange | positioned at this apparatus. It is a schematic side view of the manufacturing apparatus of the bottle can body shown in FIG. 1, Comprising: It is a figure which shows the state which has shape | molded the external thread part and the skirt part in the bottle can body cap part. It is a manufacturing apparatus of the bottle can body shown as 1st embodiment of this invention, Comprising: It is an expanded sectional side view which shows the screw | thread forming piece and skirt forming piece which are shown in FIG. It is a manufacturing apparatus of the bottle can body shown as 2nd embodiment of this invention, Comprising: It is an expanded sectional side view which shows the screw formation piece and skirt formation piece which are shown in FIG. It is an enlarged side view which shows the bottle can shown as one Embodiment of this invention. It is a manufacturing apparatus of the bottle can body shown as 3rd embodiment of this invention, Comprising: It is an expanded sectional side view which shows the screw formation piece and skirt formation piece which are shown in FIG. It is process drawing which shows the process of forming a bottle can body from a bottomed cylindrical body. It is an enlarged side view which shows a bottle can body. In the prior art example which concerns on this invention, it is an expanded side sectional view which shows the manufacturing apparatus of a bottle can body. In the prior art example which concerns on this invention, it is a figure which shows the positional relationship in each circumferential direction position of the bottle can body of the skirt shaping | molding piece and screw forming piece of the manufacturing apparatus of a bottle can body.

Explanation of symbols

4 Base part 4b Skirt formation planned part 4c Male thread formation planned part 4e Neck part formation planned part 5 Bottle can body 6 Male screw part 7 Skirt part 10, 20, 30 Manufacturing apparatus for bottle can body 11, 21, 31 Screw molding piece 12, 22 , 32 Skirt forming piece 12a, 32a Inner skirt forming piece 12b, 22b, 32b Outer skirt forming piece 13 First pressing portion (outermost peripheral portion, first convex portion)
14 2nd press part (2nd convex part)
17, 35 Sub-skirt molding piece (restraint part)
23 Groove forming piece (restraint)
24 Groove 34 First recess 36 Second recess

Claims (2)

A male screw part and a skirt part are formed on a bottle can body provided with a male screw formation scheduled part and a skirt formation planned part swelled radially outwardly connected to the lower end of the male screw formation planned part in the base part. An apparatus for manufacturing a bottle can body,
A screw-forming piece that is arranged inside and outside the base part, and forms a male screw part in the male screw formation scheduled part; and
The screw forming piece is disposed below the can axis direction, and is disposed on the inner side and the outer side of the base part, respectively, and includes a skirt forming piece that forms a skirt portion on the skirt forming scheduled part,
A restraint portion that restrains the upper portion in the can axis direction of the skirt formation scheduled portion located between the screw forming piece and the skirt forming piece in the can axis direction ;
The skirt forming piece includes an inner skirt forming piece arranged on the inner side of the base portion, and the inner skirt forming piece presses the inner peripheral surface of the lower portion in the can axis direction of the skirt forming scheduled portion outward in the radial direction. With the outermost periphery to
Between the screw forming piece and the skirt forming piece, a pressing portion that presses the outer peripheral surface of the upper portion in the can axis direction of the skirt forming scheduled portion radially inward and forms a groove portion extending in the circumferential direction. The groove forming piece provided is arranged,
The distance between the outermost peripheral part of the inner skirt forming piece and the pressing part of the groove forming piece in the can axis direction is substantially constant along the circumferential direction of the bottle can body. Manufacturing equipment. A male screw part and a skirt part are formed on a bottle can body provided with a male screw formation scheduled part and a skirt formation planned part swelled radially outwardly connected to the lower end of the male screw formation planned part in the base part. A method for manufacturing a bottle can body,
By forming a male screw portion in the male screw formation scheduled portion by means of screw forming pieces arranged on the inside and outside of the base portion,
When forming the skirt portion in the skirt formation planned portion by the skirt forming pieces disposed below the screw forming piece in the can axis direction and on the inside and outside of the base portion,
Restraining the upper part in the can axis direction of the skirt formation planned portion located between the screw forming piece and the skirt forming piece in the can axis direction ,
The skirt forming piece includes an inner skirt forming piece arranged on the inner side of the base portion, and the inner skirt forming piece presses the inner peripheral surface of the lower portion in the can axis direction of the skirt forming scheduled portion outward in the radial direction. With the outermost periphery to
Between the screw forming piece and the skirt forming piece, there is provided a pressing portion that presses the outer peripheral surface of the upper part in the can axis direction of the skirt forming scheduled portion radially inward to form a groove portion extending in the circumferential direction. A groove forming piece is disposed,
When forming the male thread portion and the skirt portion, the distance in the can axis direction between the outermost peripheral portion of the inner skirt forming piece and the pressing portion of the groove forming piece is substantially constant along the circumferential direction of the bottle can body. A method for producing a bottle can body characterized by comprising the steps of:

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