JP2018140832A - Bottle type can - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bottle type can which has its shoulder part rounded and is superior in buckling strength.SOLUTION: A shoulder part 8 is sectioned in a convex arcuate shape, a lower transition part 19 is sectioned in a convex arcuate shape with a center O2 of curvature inside and also smoothly connects with the shoulder part 8 and a trunk part 3, and an upper transition part 18 is sectioned in a concave arcuate shape with a center O1 of curvature outside and also smoothly connects with the shoulder part 8 and a mouth neck part 6, an outer diameter of the trunk part 3 being 64-68 mm, an outer diameter of the mouth neck part 6 being 36-40 mm, and the angle of a connection part between the shoulder part 8 and upper transition part 18 to a center axis of the shoulder part 8 being 35-60°.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a can molded into a bottle shape using a metal plate such as a high-strength aluminum alloy plate as a raw material, and in particular, a bottle-shaped can that can be resealed by screwing a cap onto a cylindrical mouth portion. It is about.

  This type of bottle-shaped can is described in Patent Document 1 and Patent Document 2. Both the bottle-type can described in Patent Document 1 and the bottle-type can described in Patent Document 2 are bottle-shaped cans having shoulder portions formed in a tapered shape, and are cylindrical shapes extending upward from the shoulder portions. The cap is screwed to the mouth part (or the base part). The cap is attached to the mouth by, for example, roll-on capping. In the roll-on capping, a cylindrical cap rough shape member having a top plate portion that closes the curl portion formed at the opening end of the mouth portion is covered on the mouth portion, and the cap rough shape material is pressed against the curl portion by a pressing pad. The corner part is squeezed with a pressure block, and the inner liner is brought into close contact with the curl part. In this state, the cylindrical portion (skirt portion) of the rough cap material is squeezed along the male screw portion formed in the mouth portion by the screw forming roll to form the female screw portion, and further provided at the lower end portion of the cylindrical portion. The pilfer proof band is wound around the lower portion of the turnip portion formed on the lower side of the male screw portion in the mouth portion by the roll for fastening the hem.

  During such capping, the pressing force in the axial direction (so-called plugging force), lateral force (or compression force) by each roll, torsional force by relative rotation with respect to the pressure block and each roll, etc. Works in combination. The upper portion of the shoulder portion may be partially buckled by such a capping load. Therefore, in the bottle-type cans described in Patent Document 1 and Patent Document 2, the shoulder portion is tapered in order to maintain the buckling strength. It is formed in a shape. Patent Document 3 describes a so-called smooth neck diameter reduction method in which a cylindrical mouth portion is formed simultaneously with a tapered shoulder portion. If it is a tapered shoulder, depending on the angle, the load in the axial direction and the lateral load can be received by the entire shoulder to relieve stress concentration and suppress local buckling. .

  In the bottle-type can of Patent Document 1, in order to enable reduction in thickness and weight without reducing buckling strength, an annular shape centering on the center axis of the can is formed on the upper portion of the shoulder (portion on the mouth side). By forming the concave portion and the convex portion, the rigidity of the upper portion of the shoulder portion is improved. Moreover, in the invention described in Patent Document 2, the clogging of the guide in the vending machine is prevented without impairing the buckling strength by defining the taper angle of the shoulder to a specific angle.

Japanese Patent No. 3561696 Japanese Patent No. 4159956 Japanese Patent No. 2676209

  The bottle-shaped can described in Patent Document 1 has a buckling strength by forming a concave portion or a convex portion in the upper portion of the shoulder portion (portion connected to the mouth portion) in addition to the shoulder portion having a tapered shape. It is configured to improve. Therefore, in order to maintain the buckling strength, the shape of the shoulder portion is limited to a tapered shape, and there is an inconvenience that the degree of freedom in design or the improvement or improvement in design is restricted. Moreover, since the structure currently described in patent document 1 is a structure which forms a cyclic | annular convex part and a recessed part in a shoulder upper part, the shape of the upper shoulder part which is easy to enter into a consumer's eyes is the conventional smooth The shape must be different from the shape, and there is a disadvantage that the design of the bottle-shaped can must be changed or the degree of freedom of design is restricted in this respect.

  On the other hand, since the bottle-shaped can described in Patent Document 2 is also limited to the tapered shape of the shoulder portion, as with the bottle-shaped can described in Patent Document 1, the degree of freedom in design or the improvement or improvement of the design is improved. There are inconveniences that are constrained. In addition, in the configuration described in Patent Document 2, the angle of the taper is defined, and the length in the axial direction of the shoulder is increased at that angle, so the internal capacity may be reduced. Alternatively, because the can height (height) is limited, the length of the body portion may be shortened and the guide of the vending machine may be so-called unilaterally to cause clogging of the guide.

  The present invention has been made paying attention to the above technical problem, and an object of the present invention is to provide a bottle-shaped can capable of achieving both improvement in the degree of freedom in design or design and improvement in buckling strength. It is what.

  In order to achieve the above object, the present invention is characterized in that the body and the bottom are integrally formed by drawing and ironing an A3004 or A3104 aluminum alloy plate or resin-coated aluminum alloy plate according to Japanese Industrial Standards, In a bottle-shaped can in which a shoulder portion whose outer diameter is gradually reduced toward the upper side is formed continuously on the upper portion of the trunk portion, and a cylindrical mouth portion is continuously formed on the upper portion of the shoulder portion, the shoulder portion is A cross-section in which the lower transition part connecting the shoulder part and the trunk part has a center of curvature on the inside of the trunk part or the shoulder part. The lower transition portion is formed in a convex arc shape and is smoothly continuous with the shoulder portion and the body portion, and the upper transition portion connecting the shoulder portion and the mouth portion has the center of curvature as described above. Shoulder Is formed in a concave arc shape in cross section outside the mouth part, the upper transition part is smoothly continuous to the shoulder part and the mouth part, and the outer diameter of the body part is 64 mm or more and 68 mm or less The outside diameter of the mouth part is 36 mm or more and 40 mm or less, and the angle of the tangent at the connection point between the shoulder part and the upper transition part with respect to the central axis of the shoulder part is 35 ° or more and 60 ° or less. It is a bottle-type can characterized by being.

  In this invention, the angle with respect to the central axis line of the said shoulder part of the tangent in the connection location of the said shoulder part and the said lower transition part can be 5 degrees or more and 20 degrees or less.

  In the present invention, the shoulder portion is formed in a dome shape having a convex arc shape in cross section from the lower transition portion to the upper transition portion, and the curvature radius of the convex arc shape in the shoulder portion is 40 mm. It can be set to 120 mm or less.

  Furthermore, in the present invention, the curvature radius of the lower transition part may be 2 mm or more and 4 mm or less, and the curvature radius of the upper transition part may be 5 mm or more and 14 mm or less.

  In the present invention, the thickness of the shoulder portion can be 0.20 mm or more and 0.30 mm or less.

  In the present invention, the shoulder connected to the upper side of the body part and the mouth part connected to the upper side of the shoulder part are formed by reducing the diameter of the opening end side of the body part. The upper transition part, which is the boundary between the shoulder and the mouth part, is formed in a circular arc shape that is smoothly continuous with the shoulder part and recessed inside the shoulder part or the mouth part. The angle of the tangent (the tangent to the generatrix of the shoulder) with respect to the central axis of the shoulder is 35 ° or more and 60 ° or less. Further, the lower transition portion, which is a boundary portion between the shoulder portion and the trunk portion, is formed in a circular arc shape that is smoothly continuous with the shoulder portion and protrudes to the outside of the shoulder portion or the trunk portion. The angle of the tangent line (tangent line to the generatrix of the shoulder portion) with respect to the central axis of the shoulder portion is 5 ° or more and 20 ° or less. That is, when the upper part of the shoulder represented by the tangent on the upper transition part side is a horizontal line when the central axis is a vertical line, the shoulder represented by the tangent on the lower transition part side When the lower part of the unit uses the central axis as a vertical line, the lower part stands in a vertical direction. And the shoulder part from which the angle in an upper part and a lower part differs is a dome shape with a cross-sectional convex arc shape. Therefore, since the shoulder has a rounded shape, the degree of freedom of design of the bottle-shaped can as a whole is improved, or the range of design selection is widened. Moreover, even if the shoulder is rounded so that the upper part lies in the horizontal direction, the angle with respect to the central axis of the upper part does not exceed 60 °. Since the upward component is not reduced, the bending stress is not increased, and as a result, the buckling strength is improved. Further, since the angle of the upper portion does not fall below 35 °, the roundness of the shoulder can be maintained, and the length of the shoulder (the dimension in the central axis direction) is not particularly long, and the internal capacity is reduced. Necessary and sufficient. On the other hand, since the angle of the lower part of the shoulder with respect to the central axis is 5 ° or more and 20 ° or less and is in a so-called standing state, stress is generated in the lower part of the shoulder due to the so-called plugging force during capping. However, since the compressive stress along the surface direction of the shoulder is large and the shear stress is small, deformation (buckling) such as a part of the shoulder being recessed inside can be prevented or suppressed, and as a bottle-type can The buckling strength can be improved.

It is a schematic diagram for demonstrating the process in which a bottle type can is manufactured by drawing and ironing. It is a front view of the bottle-shaped can which concerns on this invention. It is a figure which shows typically the state which has attached the cap by roll-on capping to a mouth part. It is a partial expanded sectional view which shows an example of the part which reaches a trunk | drum from a straight part via a shoulder part. It is a graph which shows collectively each data of Example 1-1 thru | or Example 1-6 and Comparative Example 1 and Comparative Example 1-1 thru | or Comparative Example 1-2. It is a chart which shows collectively each data of Example 2-1 thru / or Example 2-4, and comparative example 2-1 and comparative example 2-2.

  The bottle-shaped can according to the present invention is a metal can made of a metal plate such as an aluminum plate or a resin-coated aluminum plate, and is an aluminum alloy plate of A3004 or A3104 according to Japanese Industrial Standard (JIS), which is a particularly high strength material. Alternatively, it is a metal can formed by drawing and ironing using a resin-coated aluminum alloy plate as a raw material. Therefore, the bottle-type can according to the present invention forms an intermediate body in which the bottom plate and the body are integrated using the above metal plate as a raw material, and the smooth neck diameter reduction method described above on the opening end side of the intermediate body, etc. It is manufactured by performing necking by, for example, threading and curling. FIG. 1 schematically shows the manufacturing process. A cylindrical body 4 in which the bottom 2 and the body 3 are integrated by subjecting the metal plate 1 as a material to drawing, redrawing, and redrawing. , And further ironing is performed to increase the depth of the cylindrical body 4. At that time, doming is applied to the bottom 2. The opening end side (upper end side) of the cylindrical body 4 is cut out by trimming. Subsequently, it is set as the intermediate body 5 through a coating process. The opening end side of the intermediate body 5 is gradually reduced in diameter by necking to form the mouth part 6, and the mouth part 6 is subjected to screw / curl processing to form a bottle-type can 7.

  FIG. 2 shows an example of a bottle-shaped can 7 according to the present invention. While the body 3 is subjected to squeezing and ironing, the mouth 6 and the shoulder between the body 3 and the mouth 6 are shown. Since the diameter of the portion 8 is reduced, the thickness (wall thickness) of the shoulder portion 8 and the mouth portion 6 is relatively thick with respect to the trunk portion 3. An example of the bottle-shaped can 7 is a bottle-shaped can having an outer diameter of the body portion 3 of 53 mm (name: 202 diameter) or 66 mm (name: 211 diameter) and an outer diameter of the mouth portion 6 of 28 mm to 38 mm. In addition, this invention can be applied suitably for the bottle-type can whose outer diameter of the trunk | drum 3 is 64 mm or more and 68 mm or less, and whose outer diameter of the neck part 6 is 36 mm or more and 40 mm or less.

  The bottle-type can 7 is configured to be resealable (resealed) by attaching a cap (not shown) to the neck 6. That is, a curled part 9 wound outward is formed at the opening end of the mouth part 6, and a male screw part 10 is formed under the curled part 9. A turnip portion 11 is formed below the male screw portion 10. The turnip portion 11 engages with a pilfer proof band (not shown) provided at the lower end of the skirt portion (cylindrical portion) constituting the cap, and the pill fur proof when the cap is removed. It is a part for breaking the band from the cap and leaving it on the mouth part 6, and a bulging part 11 a having an outer diameter of the thread in the male thread part 10, and the entire circumference of the mouth part 6 on the lower side. And a formed recess 11b. The recess 11b is made clear to the consumer that the pilfer proof band separated from the cap and left on the mouthpiece 6 is loosely fitted so that it is detached from the cap, as will be described later. It is provided so that the tool for hem fastening can enter. Further, a straight portion 12 having a cylindrical shape with a substantially constant outer diameter is formed between the turnip portion 11 and the shoulder portion 8. A detailed configuration of a portion from the straight portion 12 through the shoulder portion 8 to the body portion 3 will be described later.

  FIG. 3 schematically shows a state in which the cap 13 is attached to the mouth portion 6 of the bottle-type can 7 by roll-on capping. The cap 13 is put on the mouth part 6 of the bottle-shaped can 7 that is erected with the mouth part 6 facing upward, and the cap 13 is pressed by the pressure head 14. The pressure head 14 is integrally formed with a pressing pad in the center portion and a pressure block on the outer peripheral side. The corner portion of the cap 13 is pressed and deformed by the pressure block toward the curled portion 9, and the liner 15 provided on the inner surface of the cap 13 is brought into close contact with the curled portion 9 so as to be sandwiched between the curled portion 9. When the pressing pad comes into contact with the top surface of the cap, the cap 13 is pressed in the direction of the central axis of the bottle-type can 7 to give a stoppering pressure.

  Further, the skirt portion (cylindrical portion) of the cap 13 is pressed from the outside by the screw forming roll 16 and the mouth portion 6 and the screw forming roll 16 are relatively rotated in this state, thereby the skirt portion. Is pressed against the male screw part 10 formed on the mouth part 6 and deformed along the thread groove of the male screw part 10 to form the female screw part. Further, the lower end portion of the skirt portion of the cap 13 (that is, the portion corresponding to the pilfer proof band) is brought into close contact with the above-described turnip portion 11 by the hem fastening roll 17 that relatively turns on the outer peripheral side of the neck portion 6. And squeezed to engage the lower side of the bulging portion 11a. Therefore, during roll-on capping, as shown by a thick arrow in FIG. 3, a load (plugging force) A in the direction along the central axis, and a twisting force B due to the relative rotation of the bottle-shaped can 7, A horizontal lateral force C by the rolls 16 and 17 acts in combination.

  FIG. 4 is a cross-sectional view of a portion of the bottle-shaped can 7 described above that extends from the straight portion 12 through the shoulder portion 8 to the body portion 3, and the shoulder portion 8 of the bottle-shaped can 7 according to the present invention is convex outward. It has a dome-shaped portion having a convex arc shape in cross section. The dome-shaped portion may be a portion included in the shoulder portion 8 as a part of the shoulder portion 8. In the example shown in FIG. 4, the entire shoulder portion 8 is formed in a dome shape. The curvature radius R of the convex arc is 40 mm or more and 120 mm or less when the outer diameter of the body portion 3 is 64 mm to 68 mm.

  The shoulder portion 8 is smoothly connected to each of the straight portion 12 and the trunk portion 3 on the mouth neck portion 6 side. The portion connecting the shoulder portion 8 and the straight portion 12 is the upper transition portion 18, and the center of curvature O 1 is on the outside of the shoulder portion 8 or the straight portion 12, toward the inside of the shoulder portion 8 or the straight portion 12. It has a concave arcuate cross section. The radius r of the arc is 2 mm to 4 mm. The upper transition portion 18 and the shoulder portion 8 are smoothly continuous so as not to cause a step or a corner, and a tangent with respect to the upper transition portion 18 at the connection portion (a tangent with respect to a bus of the upper transition portion 18; the same applies hereinafter). ) And a tangent to the shoulder 8 (tangent to the bus of the shoulder 8; the same applies hereinafter). The coincident tangents may be hereinafter referred to as common tangents. The shape of the upper portion of the shoulder 8 is formed such that the angle α with respect to the central axis of the common tangent line (the central axis of the bottle-type can 7) is an angle in the range of 35 ° to 60 °. In FIG. 4, the angle α is shown as an angle between a normal line at the connection point and a horizontal line orthogonal to the central axis.

  The portion connecting the shoulder 8 and the body 3 is the lower transition portion 19, and the center of curvature O 2 is on the inside of the shoulder 8 or the body 3 and toward the outside of the shoulder 8 or the body 3. It has a protruding cross-section arc shape. The radius SR of the arc is 5 mm to 14 mm. The lower transition portion 19 and the shoulder portion 8 are smoothly continuous so as not to cause a step or a corner, and a tangent to the lower transition portion 19 at the connection point (a tangent to a bus line of the lower transition portion 19; hereinafter the same). ) And a tangent to the shoulder 8 (tangent to the bus of the shoulder 8; the same applies hereinafter). The coincident tangents may be hereinafter referred to as common tangents. The shape of the lower portion of the shoulder 8 is formed such that the angle β with respect to the central axis of the common tangent line (the central axis of the bottle-type can 7) is an angle in the range of 5 ° to 20 °. In FIG. 4, the angle β is shown as an angle between a normal line at the connection point and a horizontal line orthogonal to the central axis.

  In addition, the distance SL between the respective curvature centers O1, O2 is set to 27 mm to 32 mm. Therefore, inconveniences such as the length of the body portion 3 being restricted and the internal capacity being restricted accordingly are avoided. Further, the thickness (wall thickness) t of the portion from the upper portion of the trunk portion 3 to the shoulder portion 8 and the straight portion 12 is set to 0.20 mm to 0.30 mm.

  The bottle-shaped can 7 according to the present invention has a shoulder portion 8 formed in a dome shape or a shape including at least a dome-shaped portion. That is, since it is not limited to the conventional tapered shape, it is a bottle-shaped can with a high degree of design freedom or excellent design. Moreover, even if the shoulder portion 8 has a dome shape, the portion connected to the upper transition portion 18, that is, the shape of the upper portion of the shoulder portion 8 has an angle α with respect to the central axis of the common tangent described above of 35 ° to 60 °. The shape is an angle. Therefore, the upward component of the stress against the so-called plugging force during capping does not decrease, in other words, the bending stress does not increase, and as a result, the buckling strength can be improved and the roundness of the shoulder can be maintained. In addition, the length of the shoulder (the dimension in the direction of the central axis) is not particularly long, and the internal capacity can be ensured sufficiently. Further, since the angle of the common tangent line on the lower transition portion 19 side with respect to the central axis is 5 ° to 20 °, the compressive stress along the surface direction of the shoulder portion 8 is large and the shear stress is large in the lower portion of the shoulder portion 8. Since it becomes smaller, deformation (buckling) such as a part of the shoulder 8 being recessed inward due to the capping force at the time of capping can be prevented or suppressed, and the buckling strength as the bottle-type can 7 can be improved. .

  Next, Examples and Comparative Examples performed for confirming the effects of the present invention will be shown.

  A bottle-shaped can 7 having the shape shown in FIG. 2 in which the shoulder 8 having an outer diameter of the body 3 of 66 mm and the outer diameter of the neck 6 having a diameter of 37.8 mm forms a dome shape is prepared. The buckling strength was set and analyzed. The distance SL between the centers of curvature O1 and O2 of the transition portions 18 and 19 is 29.3 mm, the radius of curvature r of the upper transition portion 18 is 3 mm, the radius of curvature SR of the lower transition portion 19 is 8 mm, and the thickness of the shoulder 8 (wall) The thickness t was set to 0.22 mm on the body 3 side and a wall thickness distribution that gradually increased in proportion to the diameter reduction so that the neck 6 side was 0.3 mm. A bottle-shaped can (Example 1-1) in which the angle β on the lower transition portion 19 side is 15 ° and the angle α on the upper transition portion 18 side is 35 ° (Example 1-1), and a bottle-shaped can in which the angle α is 40 ° (Example 1-2) ), 45 ° bottle can (Example 1-3), 50 ° bottle can (Example 1-4), 55 ° bottle can (Example 1-5), 60 ° The bottle-shaped cans (Examples 1-6) were prepared and analyzed to determine the buckling strength of each, and the angle α of the common tangent on the upper transition portion 18 side, that is, the upper angle of the shoulder portion 8 was examined. The curvature radius R of the shoulder portion 8 in Example 1-1 and Example 1-2 was 50 mm, and the curvature radius R of the shoulder portion 8 in Examples 1-3 to 1-6 was 40 mm. The analysis of buckling strength is performed by increasing the capping force by applying the capping force at the time of roll-on capping, the lateral force by each roll (about 118 N (Newton)), and the torsion torque by rotating relatively. The plugging force immediately before the occurrence of buckling deformation was analyzed and determined as the buckling strength. Moreover, in order to evaluate the moldability of each can body, it prototyped. Evaluation was made as “◯” when molding was possible without occurrence of wrinkles or depression of the shoulder, and “X” when molding was not possible due to depression of the wrinkles or shoulder 8. The evaluation results of each dimension, buckling strength and formability are shown in a table in FIG.

Comparative Example 1

  A bottle-shaped can similar to Example 1 described above was prepared as a comparative example except that the shoulder was tapered, and the buckling strength was analyzed and determined in the same manner as in Example 1 above. The shoulder taper angle was 28 ° with respect to the central axis. Further, the wall thickness (wall thickness) t of the shoulder portion is a wall thickness distribution in which the body portion side is 0.22 mm and the neck portion 6 side is 0.3 mm so that the wall thickness is gradually increased in proportion to the diameter reduction. It was configured as follows. The buckling strength was 1350 N (Newton). The dimensions, buckling strength, and evaluation results of the formability of Comparative Example 1 are collectively shown in FIG.

  Prepare comparative example 1-1 of 30 ° where the angle α of the common tangent on the upper transition part 18 side is below the range according to the present invention, and comparative example 1-2 where 65 ° the angle α exceeds the range according to the present invention, Each buckling strength was analyzed and determined. In addition, the dimension of each other part was made to be the same as that of said Example 1-1 thru | or Example 1-6. The buckling strength was 1290N (Comparative Example 1-1). In Comparative Example 1-2, wrinkles and shoulder depression occurred and could not be molded. The evaluation results of the dimensions, buckling strength, and moldability of Comparative Example 1-1 and Comparative Example 1-2 are collectively shown in FIG.

  According to the analysis results of Example 1 and Comparative Example 1, the bottle-shaped can 7 according to the present invention has a conventionally known taper whose buckling strength is known even if the shoulder portion 8 has a dome shape with a convex cross section. It exceeds the buckling strength of a bottle-shaped can having a shoulder of shape, and is at least inferior. Therefore, according to the present invention, even if the shoulder portion 8 is formed in a dome shape, a practically sufficient buckling strength can be obtained. Therefore, the degree of freedom in design and design are improved and the buckling strength is maintained or improved. Can be made compatible.

  When the above Examples 1-1 to 1-6, Comparative Example 1-1, and Comparative Example 1-2 are evaluated, according to Example 1-1 to Example 1-6, the upper transition portion 18 side The angle α of the common tangent line at the so-called sleeping state on the horizontal side allows the shoulder portion 8 to have a visually rounded dome shape with an intended appearance, and has a thick wall. Even if it was thin enough, the buckling strength became the strength required for practical use. On the other hand, in Comparative Example 1-1, although the buckling strength is a practically required strength, the shoulder portion 8 has a so-called standing shape even on the upper side, so that the appearance of the shoulder portion 8 is visually It becomes a shape close to a tapered shape rather than a rounded dome shape, resulting in a bottle-shaped can with an impression different from the intended appearance. Further, in Comparative Example 1-2, it is considered that the shoulder portion 8 is depressed or wrinkles are generated, so that the formability is inferior and is not practical.

  The angle β of the common tangent on the lower transition portion 19 side, that is, the angle of the lower portion of the shoulder portion 8 was examined. A bottle-shaped can (Example 2-1) in which the angle α on the upper transition portion 18 side is 40 ° and the angle β on the lower transition portion 19 side is 5 ° (Example 2-1). ), 15 ° bottle type can (Example 2-3) and 20 ° bottle type can (Example 2-4) were prepared, and each buckling strength was analyzed and determined. In Example 2-1, the lower portion of the shoulder portion 8 is in a so-called standing state, so that the curvature radius R of the shoulder portion 8 is set to 30 mm, whereas in Example 2-2, the curvature radius R of the shoulder portion 8 is set. Was 40 mm. Moreover, in Example 2-3 and Example 2-4, the curvature radius R of the shoulder part 8 was 50 mm, respectively. The dimensions of the other parts of the bottle-type cans of Examples 2-1 to 2-4 were the same as those of the bottle-type cans of Example 1 described above. The wall thickness (wall thickness) t of the shoulder 8 is 0.22 mm on the body side and 0.3 mm on the neck 6 side, and the wall thickness distribution is gradually increased in proportion to the diameter reduction. It comprised so that it might become. In addition, cans of various shapes were made on a trial basis and formability was evaluated. Evaluation was made as “◯” for those that could be molded without any problem in appearance, and “X” for those that could not be molded due to defects such as wrinkles in the appearance. The evaluation results of each dimension and formability are shown in a table in FIG.

Comparative Example 2

  Prepare a comparative example 2-1 of 3 ° where the angle β of the common tangent on the lower transition part 19 side falls below the range according to the present invention, and a comparative example 2-2 where the angle β exceeds the range according to the present invention, Each prototype was made to evaluate formability. The radius of curvature R of the shoulder 8 in Comparative Example 2-1 and Comparative Example 2-2 was 30 mm, and the dimensions of the other parts were the same as those in Examples 2-1 to 2-4. The evaluation results of the formability of Comparative Example 2-1 and Comparative Example 2-2 are collectively shown in FIG.

  When the above Examples 2-1 to 2-4, Comparative Example 2-1 and Comparative Example 2-2 are evaluated, according to Example 2-1 to Example 2-4, the lower portion of the shoulder 8 The angle β is 5 ° to 20 °, so that the shoulder 8 starts to be rounded from the upper end of the body 3 and is connected to the root of the mouth 6, so that the shoulder 8 is visually In addition, it has a rounded dome shape, can have an intended appearance, can be molded without causing problems, and has a buckling strength that is practically required even when the wall thickness is sufficiently thin. On the other hand, in Comparative Example 2-1, the angle β of the lower portion of the shoulder portion 8 is small, the shoulder portion 8 becomes an extension portion of the trunk portion 3, or the boundary between both becomes unclear, and the axis of the shoulder portion 8 The length of the direction (the distance SL between the centers of curvature O1 and O2) is fixed, the curvature of the shoulder 8 becomes larger, the rounded impression of the shoulder 8 is faded, and the shoulder is stretched. It became a bottle-shaped can with a different impression from the appearance. Furthermore, since the shoulder portion is loosely curved, the mold shape is not transferred due to the influence of material buckling, and wrinkles and depression of the shoulder portion occur, resulting in poor formability. Further, in Comparative Example 2-2, β was 25 °, and the shape of the shoulder portion was indistinguishable from the tapered shoulder shape, and thus the shoulder portion shape targeted by the present invention was not achieved. .

  Note that the present invention is not limited to the specific examples described above, and the shape or dimensions of the shoulder portion, the upper and lower transition portions, and the like are within the scope of the claims, You may change a dimension suitably.

  2 ... Bottom part, 3 ... Body part, 6 ... Mouth part, 7 ... Bottle type can, 8 ... Shoulder part, 10 ... Male screw part, 12 ... Straight part, 18 ... Upper transition part, 19 ... Lower transition part.

Claims (5)

The body and the bottom are integrally formed by drawing and ironing an A3004 or A3104 aluminum alloy plate or resin-coated aluminum alloy plate according to Japanese Industrial Standards, and the shoulder has a smaller outer diameter on the upper side of the body. In a bottle-shaped can in which a part is continuously formed and a cylindrical mouth part is continuously formed on the upper part of the shoulder part,
The shoulder portion has a shape including at least part of a dome shape portion having a convex arc shape in cross section,
The lower transition part connecting the shoulder part and the body part is formed in a convex circular arc shape with the center of curvature inside the body part or the shoulder part, and the lower transition part is the shoulder part and Smoothly continuous to the body,
The upper transition part connecting the shoulder part and the mouth part is formed in a cross-sectional concave arc shape with the center of curvature being outside the shoulder part or the mouth part, and the upper transition part is the shoulder part and Smoothly connected to the mouth,
The outer diameter of the body is 64 mm or more and 68 mm or less,
The outer diameter of the mouth portion is 36 mm or more and 40 mm or less,
The bottle-shaped can characterized in that an angle of a tangent line at a connection portion between the shoulder portion and the upper transition portion with respect to a central axis of the shoulder portion is 35 ° or more and 60 ° or less.
The bottle-shaped can according to claim 1,
A bottle-shaped can characterized in that an angle of a tangent line at a connection portion between the shoulder portion and the lower transition portion with respect to a central axis of the shoulder portion is 5 ° or more and 20 ° or less.
The bottle-shaped can according to claim 1 or 2,
The shoulder part is formed in a dome shape having a convex arc shape in cross section from the lower transition part to the upper transition part, and a curvature radius of the convex arc shape in the shoulder part is not less than 40 mm and not more than 120 mm. Bottle type can characterized by.
In the bottle-shaped can according to any one of claims 1 to 3,
The radius of curvature of the lower transition portion is 2 mm or more and 4 mm or less,
A bottle-shaped can having a curvature radius of the upper transition portion of 5 mm or more and 14 mm or less.
In the bottle-shaped can according to any one of claims 1 to 4,
A bottle-shaped can having a thickness of the shoulder portion of 0.20 mm or more and 0.30 mm or less.