JP3837961B2 - Simple opening can lid, tab forming method and tab forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a simple opening can lid, a tab forming method thereof, and a tab forming apparatus.
[0002]
[Prior art]
Conventionally, in a can lid manufacturing line, a tab is stamped and formed from a metal strip coil through a plurality of processes. First, a hole having a required shape is formed in the strip coil at a position corresponding to a tab hole (such as a finger hole). Formed sequentially, then punched out the outer shape of the tab material with an annular cut line excluding the connecting piece of the required width, suitably shaped in a concavo-convex shape etc. with the tab material connected to the coil with the connecting piece, and the periphery The required tab forming process such as curling is performed, and finally the connecting piece is cut to complete the tab.
[0003]
The peripheral edge of the tab is curled inside to prevent the sharp punching peripheral edge from being exposed to the outside and to ensure the strength of the tab, but the connecting piece with the coil is cut as described above. In order to perform the curl molding before this, the curling must be performed while leaving the connecting piece, and the curl is discontinuous by the width of the connecting piece at the position of the connecting piece. Therefore, the curled edge is exposed on both sides of the connecting piece cutting position. And since the connecting piece cutting part is bent so that the cutting tip edge faces inward after being cut from the coil, the connecting piece cutting part is displaced inward from the curled surface, so In other words, the curled edge is exposed so that it can be easily touched with the hand and becomes an edge, and touching the part with the hand is a disadvantage.
[0004]
[Problems to be solved by the invention]
On the other hand, in the can lid production line, about 150 to 300 produced can lids are usually automatically stacked, and in that state, the can lids are packed in a rod shape or boxed as they are, and are carried out to the can production line or the can production line. And in the can production line or the seamer of the can production line, one can lid is automatically cut out from the bottom of the can lid stack and wound around the can body. When the can lid is in a stacked state, the tab attached to the lower can lid is in contact with the back of the panel of the can lid stacked on the can lid, so that the can lid can be stacked, packaged, transported, or opened. If impact or vibration is applied to the stacked can lids at the time of packing or cutting, the edges near the connecting piece cutting part including the curled edge of the tabs rub against the panel back surface of the upper can lid, There were problems such as scratching the painted surface.
[0005]
Therefore, the present invention is intended to solve the above-described problems of the prior art, without touching the finger near the connecting piece cutting portion including the curled edge of the tab without causing irritation, It is an object of the present invention to provide a can lid having a tab processed so as not to cause scratches or the like on the painted surface of the can lid stacked on the can, and a tab forming method and a tab forming apparatus therefor.
[0006]
[Means for Solving the Problems]
The simple opening can lid of the present invention is a simple opening can lid in which a tab is riveted to the surface of the can lid panel, and the tab leaves a connecting piece cutting portion whose peripheral portion is a connecting portion with a metal strip coil. And a predetermined circumferential width and a top surface in the axial direction at a location where the curled edge of the base piece peripheral curl portion facing both sides of the connecting piece cutting portion and the connecting piece cutting portion is located. By adopting a configuration characterized in that a recess having a required depth is formed, the above-mentioned problems can be solved.
[0007]
The concave portion has a circumferential width of 1.0 to 5.0 mm and an axial depth of 0.05 to 0.60 mm, more preferably a circumferential width of 1.0 to 3.0 mm and an axial depth. Is preferably in the range of 0.05 to 0.30 mm. The size of the concave portion requires that the circumferential width is at least equal to or greater than the range including the connecting piece cutting portion and the curled edge, and if the depth in the axial direction is shallow, the effect is small. Therefore, the above range is a practical range in which the above object can be effectively achieved.
[0008]
Further, the tab forming method of the simple opening can lid of the present invention for obtaining the simple opening can lid is a tab forming method of the simple opening can lid in which the tab is rivet-fixed to the can lid panel surface. are stamped through a plurality of steps, the tab remodeling process tab peripheral portion formed by curled molded inward, leaving the connecting pieces cut portion which has been a connection portion between the metal strip coil, the connecting piece cutting portion And forming a recess having a predetermined circumferential width and a required depth from the upper surface in the axial direction at a position where the curled edge of the proximal peripheral curl portion facing both sides of the connecting piece cutting portion is formed. The peripheral curl portion is characterized by crushing and processing the back surface portion facing at least the can lid panel opening surrounded by the score. The score is inadvertently destroyed in the distribution process or the like by crushing at least the back surface portion of the base peripheral edge curl portion of the tab facing the opening portion defined by the score on the can lid panel surface. This is desirable because it can effectively prevent things.
[0009]
In the tab opening device for a simple opening can lid of the present invention, an upper die and a lower die for pressing the base end peripheral curl of the tab from the upper side and reforming are arranged in a tab reforming station, The tab has a recess-forming mold surface projecting by a predetermined height for forming a recess on the upper surface of the base end peripheral curl portion of the tab. It is desirable that the lower die has a mold surface that crushes and processes the back surface portion of the base end peripheral curl portion of the tab facing the opening of the can lid panel surrounded by the score substantially flat. . Further, in the case of a tab applied to a can lid provided so that the base end peripheral curl portion of the tab intersects the reinforcing rib formed on the can lid panel surface, the lower die is the back surface of the tab base peripheral curl portion It is desirable to have a rib relief mold surface.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 shows a steion tab that is a tab according to an embodiment of the present invention. The steion tab 1 according to the present embodiment is the same as the conventional tab in that the peripheral portion 2 is curled except for the connecting piece cutting portion 3 separated from the metal strip coil. And a concave portion 5 that is recessed by a circumferential width h and an axial depth t is formed at a location where the curled edge 4 of the base end peripheral curled portion 9 facing both sides of the connecting piece cutting portion is formed. There is. The shape of the recess 5 is shown enlarged in the plan enlarged view of FIG. 1B and the side enlarged view of FIG. As the size of the recess, a width h of 1.0 to 5.0 mm and a depth t of about 0.05 to 0.6 mm can be adopted. Desirable values are 0 mm and a depth t of about 0.05 to 0.3 mm. In FIG. 1, 6 is a rivet hole, 7 is a rivet mounting / fixing portion defining hole, and 8 is a finger engagement hole.
[0011]
By thus connecting piece cutting unit 3 and the curled edges 4,4 facing sides of the connecting piece cutting portion recessed by a predetermined length points circumferentially located, mosquitoes Lumpur when overlapped cover It is possible to effectively prevent the end edges 4 and 4 from coming into contact with the back surface of the can lid panel overlaid thereon, and to effectively generate scratches on the back surface of the can lid panel. In addition, even if the tab is touched, the connecting piece cutting portion and the curl edge are not directly touched, and the stimulation caused thereby can be avoided, and a safer can lid can be obtained.
[0012]
Next, an embodiment of the tab forming method will be described.
FIG. 3 shows a processing state in a part of the process when two rows of tabs are simultaneously punched and formed from the belt-like metal coil in the width direction. The punching of the tab is performed through a plurality of processes, and a hole having a required shape formed in the tab such as a finger hole is sequentially formed in the metal strip coil 10 and then has an annular cut line 12 excluding the connecting piece 11 having a required width. The outer shape of the tab material is punched out, the tab material 13 is connected to the coil 10 by the connecting piece 11, and is appropriately formed into a concavo-convex shape and the periphery is subjected to tab forming processing such as curl forming, and finally The connecting piece 11 is cut and separated from the strip coil to complete the tab.
[0013]
FIG. 3 shows the processing state of the tab material in the curl forming station A, the tab reforming station B, the tab hole reforming station C, and the tab cutting station D through a plurality of stations in order from the left. In each of these stations, tools for performing each processing are arranged up and down, and the processing is sequentially performed by the coils 10 being intermittently fed at a constant pitch.
[0014]
In the tab reforming station B, an upper die 15 and a lower die 25 as shown in FIGS. 4 to 7 are arranged so that the concave portion 5 can be formed on the outer periphery of the tab at the same time as the tab reforming process. . The upper die 15 has a base end peripheral curl part reforming mold 16 for reforming the base end peripheral curl part 9 near the connecting piece side from the rivet hole 6, and the connecting piece 11 is removed from the outer peripheral part of the mold. A projecting portion 17 is formed so that the inner peripheral edge 18 is engaged with the outer peripheral side portion of the base end peripheral curl portion 9 so as to be fitted downward between the annular cut line 12 and the tab peripheral portion. A base end peripheral curl reforming upper mold surface 19 is formed for pressurizing and reaming the end peripheral curl 9 from above. The protruding portion 7 is formed with a tab relief groove 20 having a required width so that the connecting piece cutting portion 3 of the tab material is positioned so as not to cut the connecting piece.
[0015]
On the other hand, in order to form the concave portion 5 in the base end peripheral curl portion 9, the base end peripheral curl portion reform upper mold surface 19 and the concave portion forming mold surface 22 projecting in substantially the same shape as the concave portion. It consists of a combination with a mold surface portion 21 indicated by a broken line in FIG. Further, as shown in FIG. 7, the lower die 25 has a base end peripheral curl reforming lower mold surface 26, and the lower mold surface 26 is in a state where the tab is riveted to the can lid panel surface. In order to prevent the lower surface of the end edge curl portion 9 from contacting the score portion formed on the lid panel surface and giving an impact to inadvertently breaking the score, at least the can lid panel opening surrounded by the score The mold surface is such that the back surface portion of the proximal end peripheral curl portion 9 that faces the surface is crushed substantially flat. Moreover, in this embodiment, since the base end peripheral curl part 9 of a tab is applied to the can lid attached so that the rib formed in the can lid panel surface may be crossed, it is tab so that a tab may not pressurize a rib. Convex rib relief groove mold surfaces 27 and 28 for forming rib relief grooves are provided on the lower surface of the base end peripheral curl portion. In the case of a can lid in which the base end peripheral curl portion 9 does not cross the rib, the rib relief groove mold surfaces 27 and 28 need not be provided.
[0016]
As described above, in the present embodiment, by providing the recess forming mold surface on the upper die in the tab reforming station of the conventional tab forming apparatus, at the same time in the tab reforming process, the base piece peripheral edge curl portion of the tab is cut. The recessed portion 5 having a required depth can be formed from the upper surface in a range including the curled edges facing both sides of the portion and the connecting piece cutting portion, and can be easily performed without increasing the number of steps of the conventional tab forming step. A tab that achieves the above object can be formed.
[0017]
【The invention's effect】
As described above, according to the simple opening can lid of the present invention, from the upper surface to the range including the connecting piece cutting portion and the curled edge facing both sides of the connecting piece cutting portion of the base end peripheral curl portion of the tab. Since the recess of the required depth is formed, touching the proximal edge curl of the tab will not cause irritation and will cause scratches on the back of the can lid panel with the can lid stacked A simple open can lid is obtained.
[0018]
Moreover, according to the tab forming method and the forming apparatus of the simple opening can lid of the present invention, it can be easily applied to the conventional tab forming line simply by changing the mold surface without increasing the number of steps, and the manufacturing cost is increased. The simple opening can lid which achieves the said objective can be obtained without. In addition, the concave portion is formed in the base end peripheral curl portion, and the back surface portion facing the opening of the can lid panel surrounded by at least the score of the base end peripheral curl portion is crushed and processed substantially flat, so that a distribution process or the like is performed. In this case, it is possible to effectively prevent an accident that the tab presses the opening of the can lid and the score is carelessly broken.
[Brief description of the drawings]
1A is a plan view of a tab of a simple opening can lid according to an embodiment of the present invention, FIG. 1B is an enlarged view of a main part thereof, and FIG. 1C is an enlarged side view thereof.
FIG. 2 is a cross-sectional view taken along the line AA of FIG.
FIG. 3 is a plan view showing a processing state in a step of punching and forming a tab from a strip-shaped metal coil.
FIG. 4 is a cross-sectional view showing a processing state in the A station.
FIG. 5 is a bottom view of the upper die.
6A is a view in the direction of the arrow C in FIG. 5, and FIG. 6B is a cross-sectional view taken along the line BB.
FIG. 7 is a plan view of the main part of the lower die.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Steion tab 3 Connection piece cutting | disconnection part 4 Curl edge 5 Recessed part 10 Coil 11 Connection piece 13 Tab material 15 Upper die | dye 16 Base edge peripheral curl part reforming mold 17 Protrusion part 19 Base end peripheral curl part upper mold surface 20 Tab Relief groove 22 Recess mold surface 25 Lower die 26 Base end peripheral curl reform lower mold surface 17, 28 Rib relief mold surface

Claims (5)

It is a simple opening can lid in which a tab is riveted to the can lid panel surface, and the tab is curled on the inside leaving a connecting piece cutting part whose peripheral part is a connecting part with a metal strip coil, A recess having a predetermined circumferential width and a required depth from the upper surface in the axial direction is formed at a position where the curled edge of the base piece peripheral curl portion facing both sides of the connecting piece cutting portion and the connecting piece cutting portion is formed. A simple opening can lid characterized by having.   The simple opening can lid according to claim 1, wherein the recess has a circumferential width of 1.0 to 5.0 mm and an axial depth of 0.05 to 0.60 mm. A tab forming method for a simple opening can lid in which a tab is riveted to the surface of a can lid panel, which is stamped and formed from a metal strip coil through a plurality of steps, and a peripheral portion is a connecting portion with the metal strip coil tab remodeling process tab formed by curled molded inward, leaving the connecting pieces cut portion, locations curled edge of the proximal end peripheral curl portion facing both sides of the connecting piece cutting portion and said connecting piece cutting unit is positioned In addition, a recess having a predetermined circumferential width and a required depth in the axial direction is formed from the upper surface, and at least the back surface portion of the base end peripheral curl portion facing the opening of the can lid panel surrounded by the score is substantially flat. A method for forming a tab of a simple opening can lid, which is crushed into pieces.    A tab forming device for a simple opening can lid in which a tab is riveted to the surface of a can lid panel. The upper die has a recess-forming mold surface that protrudes by a predetermined height for forming a recess on the upper surface of the base end peripheral curl portion of the tab. apparatus.   6. The lower die has a mold surface for crushing and processing the back surface portion of the base end peripheral curl portion of the tab facing the can lid panel opening portion surrounded by at least a score substantially flat. Tab opening device for simple opening can lid.

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