JP4433238B2 - Trimming cutter device for bottle-shaped cans - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a trimming cutter device for cutting and opening a tip portion of an unopened mouth and neck in a bottle-shaped can manufacturing process, and in particular, a coated metal thin plate in which both surfaces of a metal thin plate are coated with a thermoplastic resin layer The present invention relates to a trimming cutter device for trimming a mouth-and-neck portion without generating a so-called film hair.
[0002]
[Prior art]
Integrated into a bottle shape with a two-piece can with a can body and bottom integrally formed by an appropriate method such as drawing and deep drawing (drawing / redrawing) from a thin metal plate of aluminum or steel, or polyethylene terephthalate resin Each of the molded PET bottles has been widely used as a variety of beverage containers in the past as a lightweight container in place of a heavy glass bottle. In a two-piece can, it is fastened and fastened to the flange at the top of the can body. Open the easy open end (end plate with simple opening) by pull tab operation, and for PET bottles, open the pill fur proof cap attached to the neck and neck of the bottle and remove it. Thus, the consumer can drink the beverage in the container.
[0003]
In such beverage containers, PET bottles with a mouth-and-neck portion are easy to drink when drinking directly from the container and can be resealed with a cap, but they must be handled with care because they are easily deformed by heating. In addition, there is a problem that the shelf life of the contents is shortened due to inferior gas permeation resistance and light shielding properties, and there is a problem that rapid cooling is inferior when the contents are cooled in a refrigerator, and resources are recovered and recycled. The rate is very low so far, so it is excellent in heat resistance, gas permeation resistance, light-shielding property, quick cooling property, etc. and is a two-piece metal thin plate with a high resource recycling rate In the past, it has been studied to increase convenience by adding a function that can be molded into a bottle shape having a mouth-neck portion and resealable with a screw cap.
[0004]
As a metal can that can be resealed with such a screw cap, a small-diameter mouth-neck part, a shoulder part having an inclined surface and a large-diameter body part are integrally formed so as to have a shape similar to that of a PET bottle. The bottom of the can opposite the mouth and neck is sealed by tightening and fixing a separate bottom lid, and a screw cap is screwed onto the opened mouth and neck. No. 10-509095 discloses a bottle-shaped can as an example.
[0005]
[Problems to be solved by the invention]
By the way, regarding the bottle-shaped can made of a thin metal plate in which the mouth / neck part, shoulder part, and body part are integrally molded, the above cited gazette includes protection on the metal surface of the can for the protection of the contents and the corrosion resistance of the can. In the case of applying a coating, it is stated that if a protective coating is pre-coated on a thin metal plate, the protective coating will be damaged during the ironing process for can molding. However, it is practically difficult to apply the protective coating to a uniform thickness on the inner and outer surfaces of the can in which the narrow neck and neck and the curved shoulder are formed.
[0006]
Therefore, the present inventors previously laminated on both surfaces of the metal thin plate as the material of the can as a protective coating with a thermoplastic resin that has good followability to the elongation and bending of the metal thin plate and serves as a lubricant when processing the metal thin plate. In addition, from a thin metal plate coated with a thermoplastic resin layer on both sides, the body, shoulder and neck of the can are integrally formed, and further, a curled part and a screw part are formed on the mouth and neck. I decided to adopt it.
[0007]
However, when manufacturing a bottle-shaped can from such a coated metal sheet, the coated metal sheet is punched out and formed into a cup shape, and then formed into a bottomed cylindrical can with a small-diameter body. Then, after forming the bottom side of the bottomed cylindrical can into the shoulder and the unopened mouth and neck, in the mouth and neck trimming step of cutting and opening the tip of the unopened mouth and neck There is a problem that a part of the thermoplastic resin layer coated on the side wall of the mouth-and-neck part is hair-like (or flare-like) and extends from the cut end part, so-called film hair is noticeably generated. understood.
[0008]
Then, when the cause of the above film hair was examined, the following things were found. That is, in order to trim the front end portion of the unopened mouth and neck, the inner cutter inserted inside the mouth and neck and the outer cutter moving outside the mouth and neck are offset with a predetermined clearance. A trimming cutter device is used that shears with the inner blade at the corner of the inner cutter and the outer blade at the corner of the outer cutter sandwiching the side wall of the mouth and neck. In such a device, the inner cutter is placed inside the can. The support shaft of the inner cutter is cantilevered and long because it is inserted into the deepest neck and neck.
[0009]
Therefore, when shearing with the inner blade at the corner of the inner cutter and the outer blade at the corner of the outer cutter sandwiching the side wall of the mouth and neck, as shown in FIGS. 7 (A) and 7 (B), from the outer cutter 12 The support shaft of the inner cutter 11 is bent by the pressing force, and as a result, a part of the shear pressing force due to the movement of the outer cutter 12 is a direction in which the inner blade 11a and the outer blade 12a are offset by a predetermined clearance (clearance is reduced). Film hair frequently occurs because the cutter clearance fluctuates by working in the spreading direction.
[0010]
An object of the present invention is to solve the above-described problems. Specifically, both sides of a trimming cutter device for trimming a mouth-and-neck portion in a manufacturing process of a bottle-shaped can have thermoplastic resin layers on both sides. It is an object to prevent film hair from being conspicuously generated from a thermoplastic resin layer when the mouth-and-neck portion covered with is trimmed.
[0011]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a bottle-shaped can in which a mouth neck portion, a shoulder portion, and a body portion are integrally formed from a coated metal thin plate in which both surfaces of a metal thin plate are covered with a thermoplastic resin layer. In the process, in order to cut and open the tip portion of the unopened mouth-neck portion, it is supported by the tip portion of the shaft provided in a cantilever shape, and passes through the inside of the can from the opening end portion of the trunk portion One inner cutter inserted inside the mouth and neck and one outer cutter moving outside the mouth and neck. In the trimming cutter device that is sheared by sandwiching the side wall of the mouth and neck with an outer blade, the side surface of the mouth and neck that extends along the side wall of the mouth and neck from the blade edge of each cutter, the side wall of the mouth and neck as the inner cutter moves away from the edge Or Tilted away, the outer cutter is characterized in that the tilting so as to approach the side wall of the neck as the distance from the cutting edge.
[0012]
According to the above-described trimming cutter device for a bottle-shaped can, when the inner cutter and the outer cutter have the inner and outer cutters sandwiching the side and neck side walls and shearing, the inner cutter is pressed by the pressing force from the outer cutter. 6A and 6B, the pressing force of the outer cutter 12 works so as to first press the side wall of the mouth neck portion 4 against the inner blade 11a of the inner cutter 11 as shown in FIGS. It is possible to shear the side wall of the mouth and neck without releasing the pressing force for shearing in the direction in which the cutter clearance spreads. Absent.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a trimming cutter device for a bottle-shaped can of the present invention will be described in detail based on the drawings.
[0014]
FIG. 1 shows an example of a bottle-type can in which a mouth-and-neck portion, a shoulder portion, and a body portion are integrally formed. The bottle-type can 1 has a circular section in a vertical direction upward from a large-diameter cylindrical body portion 2. A small-diameter cylindrical mouth-and-neck portion 4 is integrally formed through an arc-shaped dome-shaped shoulder portion 3, and the lower end opening portion of the body portion 2 is sealed by tight fastening of the bottom lid 5. In addition, an outer curled portion 41, an inclined wall 42, a screw forming portion 43, a bead portion 44, and a small diameter cylindrical portion 45 are formed in the mouth / neck portion 4 whose upper end is opened.
[0015]
FIG. 2 shows an outline of the manufacturing process of the bottle-shaped can shown in FIG. 1, and uses a coated metal sheet in which a thermoplastic resin coating layer is formed on both surfaces of the metal sheet and a lubricant is applied. First, in the cup forming process, the blank obtained by punching the coated metal thin plate into a disk shape is drawn into a cup shape, and then in the next can body forming process, at least once for the cup. It is formed into a bottomed cylindrical can with a small diameter and thinned body by re-drawing, bending and stretching, and ironing.
[0016]
Next, in the top dome molding process, after forming the shoulder part and the unopened mouth and neck by performing drawing processing a plurality of times on the bottom side of the bottomed cylindrical can, in the lubricant removing process, Lubricant is removed from at least the outer surface of the can with the mouth and neck not open and the lower end of the body open, and the can end is trimmed on the open end side of the body opposite to the mouth and neck in the can body trimming process. Is sent to the printing / painting process.
[0017]
In the printing / painting process, the barrel, shoulders, and unopened mouth and neck are integrally molded and the lower end of the barrel is open. A top coat is applied after printing (characters, decorative patterns, etc.), and in a subsequent drying step, the printing ink layer and the top coat layer are sufficiently dried and the thermoplastic resin coating layer is made amorphous.
[0018]
Then, in the screw / curl molding step, first, the mouth neck portion is opened by trimming the tip portion of the unopened mouth neck portion, and then the opening end portion is formed into an annular curled portion by external winding, A screw for screwing a cap is formed on the cylindrical peripheral wall, and a bead portion is formed below the screw forming portion.
[0019]
Next, in the neck and flange forming process, the neck-in process and the flange process are sequentially performed on the lower end opening end of the body part opposite to the mouth and neck part, and then in the bottom cover winding process (not shown) 1 by fixing the bottom lid of another member made of a thin metal plate integrally to the flange portion formed at the lower end opening of the body portion by a double winding method using a (can lid winding machine). A bottle-shaped can as shown in Fig. 1 is completed.
[0020]
The production of the bottle-shaped can by each process as described above will be described in more detail. The coated metal sheet as a raw material is preliminarily thermoplastic such as a polyester resin or a polypropylene resin on both surfaces of a metal sheet such as an aluminum alloy sheet or a surface-treated steel sheet. A coated metal thin plate having a thickness of 0.1 to 0.4 mm laminated with a resin film, for example, a 3004H191 aluminum alloy plate having a thickness of 0.315 mm, and polybutylene terephthalate resin (PBT) and polyethylene terephthalate A coated metal thin plate obtained by laminating a film of a mixed resin (PBT: PET = 60: 40) with a resin (PET) so as to have a thickness of 20 μm on the inner surface side and a thickness of 20 μm on the outer surface side is used.
[0021]
The method of laminating the thermoplastic resin film on the metal thin plate is not limited to the case where the thermoplastic resin film formed in advance is directly bonded to the metal surface of the metal thin plate, but the thermoplastic resin melted from the T die is preheated. When extruding onto a thin metal plate and directly adhering it, a thermoplastic resin film previously formed into a film is bonded via an adhesive primer layer, a curable adhesive layer or a thermoplastic resin layer with good thermal adhesion. May be thermally bonded to metal surfaces. In this laminating process, it is preferable from the viewpoint of workability and adhesiveness that the thermoplastic resin film that has been heat-bonded is once melted (for example, by passing it through water) and then rapidly cooled to be amorphous. .
[0022]
For such a metal sheet having a thermoplastic resin film layer formed on both sides, normal butyl stearate, liquid paraffin, petrolatum, polyethylene wax, cooking oil, hydrogenated on the thermoplastic resin film layer on both sides. One or more kinds of edible oil, palm oil, synthetic paraffin, dioctyl sebacate, etc. are applied as a lubricant, and the coated metal sheet coated with this lubricant is used as a material in the cup molding process. Each blank is punched into a blank and formed into a cup by drawing. For example, a blank punched into a 170 mm diameter disc is drawn into a cup shape with a height of 48.3 mm and an outer diameter of 100 mm. .
[0023]
In the can body forming process for the cup formed in such a manner, it is further bent and stretched in one of two redrawing processes, and then subjected to a squeezing process so that the diameter is smaller than that of the cup. Molded into a bottomed cylindrical can with a thin barrel at the height, and the bottom corner of the bottomed cylindrical can (the trunk near the bottom and the bottom) has an arc-shaped shoulder For example, a cup having a height of 48.3 mm and an outer diameter of 100 mm is formed into a bottomed cylindrical can having a height of 171.5 mm or more and an outer diameter of 65.9 mm. .
[0024]
In contrast to a can whose entire bottom is formed into a cylindrical shape and whose can bottom corner portion is pre-shaped into a shoulder curved surface, in the top dome molding process, as shown in FIG. By punching a flat can bottom surrounded by a corner of the can bottom preformed on the shoulder curved surface with a wrinkle pressing tool (die and pusher) with a curved surface closely contacting the curved shoulder portion After drawing into a bottomed cylindrical shape with a smaller diameter than the barrel, the newly drawn bottomed cylindrical part is a taper with a straight section that approximates the virtual curved section arc following the pre-shaped shoulder curved surface Using a wrinkle holding tool (die and pusher) having a surface, it is drawn into a cylindrical shape with a smaller diameter by punching.
[0025]
Then, by repeating such a drawing process once again, the diameter of the bottomed cylindrical portion is reduced until it becomes substantially the same as the diameter of the mouth and neck, and then the initial shoulder is obtained by repeating such drawing process. A plurality of tapered surfaces of the shoulder formed following the curved surface are extended by a pair of forming tools (die and pusher) having a virtual curved surface extending from the shoulder curved surface, so that a continuous smooth curved surface is obtained. After re-molding (reforming), as shown in FIG. 4, the mouth-and-neck portion formed into a bottomed cylindrical shape is subjected to mouth-drawing twice.
[0026]
In order to remove the lubricant such as normal butyl stearate, liquid paraffin, and synthetic paraffin applied to both the inner and outer surfaces of the can in the lubricant removal step for the top dome-shaped can as described above, for example, Wash the lubricant by spraying a well-known degreasing agent and water or hot water on the inner and outer surfaces of the can or wash the lubricant, or heat the can to a high temperature of about 200 to 300 ° C. (preferably 255 to 300 ° C.) By doing so, the lubricant is volatilized.
[0027]
When a cleaning method is used to remove the lubricant, a can washer used in the degreasing / cleaning process of the squeezed iron can can be used, and when the lubricant is volatilized, the opening side should be lowered. Then, the hot air may be blown while the can is placed on the net conveyor and conveyed. When the thermoplastic resin film layer is amorphized again in the lubricant removing step, the temperature of the hot air is set to a temperature higher than the melting point of the thermoplastic resin, and after spraying the hot air, Cold air (20 ° C. or lower, preferably 15 ° C. or lower) may be blown.
[0028]
For cans that have been molded with a top dome and from which at least the outer surface lubricant has been removed, the bottom end opening end side of the body is trimmed in the can body trimming process, and the can is aligned to a predetermined length before printing and painting processes. This printing / painting process is not shown in the figure, but the outer surface of the cylindrical body of the two-piece can (can body before fixing the cover plate) is transported by a mandrel. For example, an appropriate apparatus used for continuously printing and coating (for example, JP-A-48-58905, JP-A-54-92810, JP-A-57-170758, JP, 57-178754, A, etc.).
[0029]
In the drying process after the printing / painting process, the printing ink layer and the topcoat layer of the can are dried simultaneously with the thermoplastic resin film covering both sides of the can (for example, polybutylene terephthalate resin and polyethylene terephthalate resin). Adhesive strength between the resin film and the aluminum alloy plate before entering the screw / curl molding process by heating to the melting point of the mixed resin film) and then rapidly cooling to amorphize the thermoplastic resin film layer. To improve.
[0030]
As for the amorphization of the thermoplastic resin film layer, the thermoplastic resin coating layer formed in the amorphized state from the beginning on the coated metal thin plate is subjected to subsequent molding (cup molding, can barrel). In the molding and top dome molding), the thermoplastic resin coating layer is crystallized by stretching, but before entering the screw / curl molding process for severe processing, it is amorphized again and the aluminum alloy plate This is to reinforce the adhesive strength between the two.
[0031]
This amorphization of the thermoplastic resin film layer may be carried out at the same time when the can is heated to a high temperature in the previous lubricant removal step to volatilize the lubricant, Prior to molding, it may be amorphized by a separate amorphizing device, but in the existing process before entering the screw / curl molding process, it can be made amorphous at the same time as heating the can in that process. It can implement efficiently, without providing the apparatus for exclusive use for quality improvement.
[0032]
For the can in which the body is printed (and top coat) and the thermoplastic resin film layer of the protective coating is made amorphous again, in the screw / curl molding process, first, as shown in FIG. After opening the mouth and neck by trimming the tip part (upper end small diameter part) of the mouth and neck part that has been subjected to two times of mouth drawing from the cylindrical shape, the outer side as shown in FIG. The winding curl portion 41, the inclined wall 42, the screw forming portion 43, the bead portion 44, and the small diameter cylindrical portion 45 are formed into a shape.
[0033]
That is, after cutting and opening the small diameter portion at the upper end of the mouth and neck, the opening edge is slightly precurled outward, and then a die having a curved surface with an arc-shaped cross section at the upper edge is provided. With the curl forming punch pushed down from above, the curled part of the outer winding is formed at the upper edge opening edge of the mouth-and-neck part, and then the vertical section swells outward from the lower inclined wall. Molded into a curved surface with an arc shape
[0034]
Then, the cylindrical peripheral wall that follows the inclined wall below the curled part is formed into a screw forming part. Regarding the method of forming the thread and the thread valley at that time, a female die is inserted inside the mouth and neck part. There are a method of forming by pressing the roll from the outside, a method of forming by pressing the roll from the inside of the mouth and neck, etc. After forming the screw by an appropriate method, leave the lower part of the screw forming part by a predetermined width In this state, the lower part is pressed from the outside to form a small diameter cylindrical part, so that the lower part of the screw forming part is formed into an annular bead part.
[0035]
For the bead part and the small-diameter cylindrical part below it, when a metal pill fur proof cap is attached to the mouth-and-neck part by the capper, the roller of the capper enters the small-diameter cylindrical part and the lower end wall of the cap (for breaking By deforming the lower end of the belt-like part at the bottom of the perforation and pressing the lower end wall of the cap against the lower side wall (lower step) of the bead part, the cap is placed in a pill fur-proof state (when opened) Is a state in which the perforation is broken so that the fact can be seen in appearance).
[0036]
For the cans that have been molded with the neck and neck as described above, in the neck and flange molding process, the neck-in process and the flange process are sequentially performed on the lower end opening end of the body part opposite to the mouth and neck part. Then, in the bottom lid winding process, the bottom lid of another member is double-tightened and fixed to the flange formed at the lower end opening of the can by a seamer (can lid clamping machine). The bottom lid is made of, for example, an aluminum alloy in which a mixed resin film of a polybutylene terephthalate resin and a polyethylene terephthalate resin having a thickness of 0.02 mm is thermally fused on both sides ( 5182-H39), a bottom lid having a thickness of 0.285 mm and a diameter of 62.6 mm is used.
[0037]
By the way, in the manufacture of the bottle-shaped can as described above, as shown in FIG. 4, in the first step of the screw / curl forming process, after forming into a bottomed cylindrical shape, two times of mouth drawing are performed. The open neck of the bottle-shaped can is opened by trimming the tip (the upper end small diameter portion) of the mouth and neck of the unopened mouth and neck. An embodiment of the trimming cutter device of the present invention used for trimming will be described below.
[0038]
FIG. 5 shows the overall structure of a trimming cutter device for trimming an unopened mouth-and-neck portion of a bottle-shaped can. FIGS. 6 (A) and 6 (B) show the trimming cutter device of this embodiment. FIG. 7A and FIG. 7B show a state when the mouth and neck are trimmed by the trimming cutter device of the comparative example.
[0039]
As shown in FIG. 5, the trimming cutter device 10 for trimming the unopened mouth-and-neck portion of the bottle-type can passes through the inside of the mouth-and-neck portion 4 from the opening portion at the end of the body portion 3. And an outer cutter 12 that moves in the cutting direction (direction orthogonal to the axial direction of the mouth-and-neck portion 4) on the outer side of the mouth-and-neck portion 4, with a predetermined clearance. The offset inner cutter 11a at the inner cutter corner and outer cutter 12a at the outer cutter corner sandwich the side wall of the distal end portion (upper end small diameter portion) of the mouth-and-neck portion 4 for shearing.
[0040]
That is, in the trimming cutter device 10 of the present embodiment, the inner cutter 11 inserted inside the mouth-and-neck portion 4 is fixedly supported on the distal end portion of the rotating shaft 13 that is inserted into the can and positioned at the axial center of the can body. The outer cutter 12 that moves in the cutting direction outside the mouth-and-neck portion 4 is fixed to a rotating shaft 14 that reciprocates in the cutting direction (direction perpendicular to the axial center direction of the mouth-and-neck portion 4). The corner 11a at the tip of the inner cutter 11 is the inner blade of the round blade, and the corner 12a at the tip (the side facing the inner cutter 11) of the outer cutter 12 is the outer blade of the round blade.
[0041]
Then, the inner cutter 11a and the outer cutter 12a are a rotary shear formed by two rotating round blades, and the axial direction of each cutter is sandwiched between the side walls of the mouth and neck portion 4 to be cut. The outer blade 12a is moved in the cutting direction (direction perpendicular to the axial direction of each cutter) with respect to the inner blade 11a which is arranged in an offset state with a predetermined clearance and whose position is fixed in the can. It is installed to do.
[0042]
In such a trimming cutter device 10, in the comparative example, as shown in FIG. 7A, the blade side surfaces extending along the side walls of the mouth neck 4 from the blade edges 11 a and 12 a of the cutters 11 and 12 are both provided. In contrast to the cylindrical surface parallel to the side wall of the mouth-and-neck part 4, in this embodiment, as shown in FIG. 6A, the side walls of the mouth-and-neck part 4 from the cutting edges 11a and 12a of the cutters 11 and 12, respectively. In the inner cutter 11, the side surface of the blade extending along the inner cutter 11 is formed to be a conical surface that is inclined so as to be separated from the side wall of the mouth neck portion 4 as it is away from the blade edge 11a. The conical surface is inclined so as to approach the side wall of the neck 4.
[0043]
In addition, about the inclination | tilt angle of the blade side surface of each cutter 11 and 12, from the viewpoint of prevention of a deformation | transformation of the mouth-and-neck part 4 and generation | occurrence | production of a film hair, in the inner cutter 11a of an inner cutter corner part, In the range of 5 to 11 degrees (for example, 8 degrees) with respect to the axial direction of the neck 4, and in the outer cutter 12 a at the corner of the outer cutter, the axial direction of the cutter 12 (the axial direction of the mouth neck 4) Is preferably in the range of 1 to 5 degrees (for example, 3 degrees).
[0044]
According to such a trimming cutter device 10 for a bottle-shaped can of this embodiment, when shearing with the inner cutter 11 of the inner cutter 11 and the outer cutter 12 of the outer cutter 12 sandwiching the side wall of the neck portion 4, As shown in FIG. 6B, even if the support shaft of the inner cutter 11 is bent by the pressing force of the outer cutter 12, the pressing force of the outer cutter 12 causes the side wall of the neck 4 to be moved to the inner blade 11 a of the inner cutter 11. In the pressed state, the side wall of the mouth and neck portion 4 can be sheared without releasing the pressing force for shearing in the direction in which the cutter clearance widens, thereby preventing the occurrence of film hair due to variations in the cutter clearance. be able to.
[0045]
In the trimming cutter device as shown in the comparative example, the support shaft of the inner cutter 11 is bent by the shear pressing force of the outer cutter 12 as shown in FIG. A part of the pressure works as a force in the direction in which the inner blade 11a and the outer blade 12a escape (the direction in which the clearance widens), so that the cutter clearance varies, and as a result, noticeable film hair is generated. It becomes.
[0046]
As mentioned above, although one embodiment of the trimming cutter device for bottle type cans of the present invention was described, the present invention is not limited to the above embodiment. For example, the bottle type can to be used is described above. It is not limited to what is specifically shown in the embodiment, and the specific structure of the trimming cutter device (for example, the support structure of the outer cutter and the inner cutter) is also the structure shown in the figure. Needless to say, the design can be changed as appropriate.
[0047]
【The invention's effect】
According to the trimming cutter device for a bottle-shaped can of the present invention as described above, when trimming the mouth and neck part whose both sides are covered with the thermoplastic resin layer, the film hair is conspicuous from the thermoplastic resin layer. Occurrence can be prevented, and the mouth and neck of the can can be finished in a clean state without film hair without requiring a process for removing the film hair again after that.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional side view showing an example of a bottle-shaped can manufactured using a trimming cutter device of the present invention.
2 is an explanatory side view showing a manufacturing process for manufacturing the bottle-shaped can shown in FIG. 1. FIG.
FIG. 3 is a cross-sectional explanatory view showing a state of molding of the neck and neck in the top dome molding process in the manufacturing process of the bottle-shaped can shown in FIG. 2;
4 is an explanatory side view showing two mouth-drawing moldings in the top dome molding process in the manufacturing process of the bottle-shaped can shown in FIG. 2 and subsequent trimming of the mouth-and-neck portion. FIG.
5 is a cross-sectional side view showing the entire trimming cutter device used for trimming the mouth and neck shown in FIG. 4; FIG.
6A and 6B are side views illustrating a trimming cutter device according to an embodiment of the present invention, wherein (A) the state of the inner blade and the outer blade before driving, and (B) the state of the inner blade and the outer blade immediately before cutting, respectively. Figure.
7A and 7B are side explanatory views showing (A) the state of the inner blade and the outer blade before driving, and (B) the state of the inner blade and the outer blade just before cutting, respectively, regarding the trimming cutter device of the comparative example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Bottle type can 2 Body part 3 Shoulder part 4 Mouth neck part 10 Trimming cutter apparatus 11 Inner cutter 11a Inner blade (blade edge of inner blade)
12 Outer cutter 12a Outer blade (outer blade edge)

Claims (2)

In the manufacturing process of a bottle-shaped can where the neck and neck, shoulder and body are integrally molded from a coated metal sheet with both sides of the metal sheet covered with a thermoplastic resin layer, the tip of the unopened mouth and neck is cut. One inner cutter that is supported by the tip end portion of the shaft provided in a cantilever shape and is inserted into the inside of the mouth and neck portion through the can from the opening end portion of the trunk portion , With one outer cutter that moves outside the mouth and neck, shearing with the inner blade at the corner of the inner cutter and the outer blade at the corner of the outer cutter offset by a predetermined clearance, sandwiching the side wall of the mouth and neck In the trimming cutter device, the blade side surface extending from the blade edge of each cutter along the mouth-neck side wall is inclined so as to be separated from the side wall of the mouth-neck part as it is away from the blade edge in the inner cutter, and in the outer cutter Trimming cutter device for bottle-shaped cans, characterized in that it is inclined so as to approach the side wall of the neck as the distance from the. The blade side surface of the inner cutter at the corner of the inner cutter is inclined within a range of 5 to 11 degrees with respect to the axial direction of the mouth-and-neck portion, and the blade side surface of the outer cutter at the corner portion of the outer cutter is in the axial direction of the mouth-and-neck portion 2. The trimming cutter device for a bottle-shaped can according to claim 1, wherein the trimming cutter device is inclined within a range of 1 to 5 degrees with respect to the angle.

Images