JP3791329B2 - Easy-to-open cans and can lids - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an easy-opening can having a partial opening or a full-opening, and more particularly to an easy-opening can provided with a pressure confirmation unit, its can lid, and a can bottom.
[0002]
[Prior art]
In recent years, canned foods (for example, agricultural and fishery products, processed foods, sauces, soups, etc.) are required to have easy opening as with beverage cans, and easy-opening can lids have been attached. Some of these easy-open food cans maintain the internal pressure of the can in a negative pressure state. The negative pressure can is kept sealed until the consumer opens it, and is kept in a negative pressure state at the distribution stage.
[0003]
[Problems to be solved by the invention]
However, in the case of easy-open cans, since the score is formed on the can lid, if the retort sterilization or handling at the distribution stage is not appropriate, the score may crack and the sealing performance may be impaired. .
However, conventional easy-to-open cans have no confirmation means for confirming whether the internal pressure is appropriate, and it is difficult to judge even if there is a poor sealing performance.
[0004]
On the other hand, easy-opening can lids require easy opening of the lid, but negative pressure cans generally have a tendency to be difficult to open because the can lid warps inward as a whole. . As countermeasures, measures such as providing a recess under the tab portion of the tab or providing a projection on the panel portion under the tab to float the tab are taken.
However, if the depth of the concave or convex portion is increased to increase the distance between the tab and the panel portion, other can lids may get stuck between the tab and the panel during manufacture and transportation of the can lid. There has been a problem that the concave portion comes into contact with another lid and is easily damaged.
[0005]
The present invention has been made to solve the above-mentioned problems of the prior art, and the purpose of the present invention is to make it easy to visually recognize whether sealing is being performed from the outside, and also by sounding when opening. An object of the present invention is to provide an easy-to-open can, its can lid, and a bottom of the can that can be checked for sealing performance, have no problems in manufacturing damage and transportability, have good finger gripability, and are easy to open.
[0006]
[Means for Solving the Problems]
To achieve the above object, the present invention comprises a can body and a can lid that is fastened and fixed to the upper end opening of the can body, and the can lid surrounds a planned opening area. And an easy-open can provided with a tab for breaking the score,
The can lid is elastically deformed inward by the negative pressure inside the can body before opening, and is provided with a pressure confirmation portion that generates sound by elastic recovery at the same time as opening, so that the tab portion of the tab is placed on the pressure confirmation portion A gap is formed between the pressure check part, which is fixed by winding and elastically deformed inward by negative pressure, and the tab pick part, and in the free state, the tab pick part and the pressure check part are in close contact with each other. It is characterized by.
[0007]
The pressure confirmation part includes a step part protruding upward from the peripheral part of the panel part of the can lid, and a button part formed to protrude from the upper surface of the step part. It is characterized by closely contacting the button part with no gap.
In addition, the pressure confirmation portion includes a step portion that protrudes upward from the peripheral portion of the panel portion of the can lid, and a button portion that is formed to protrude on the upper surface of the step portion. The positional relationship is set so as to contact the edge of the button portion in a free state .
[0008]
In addition, in a can lid of an easy-opening can comprising a lid body provided with a score surrounding the planned opening area, and a tab attached to the lid body to break the score,
The lid body is provided with a pressure confirmation portion that elastically deforms inside by the negative pressure inside the can body before opening, and elastically recovers at the same time as opening, and the tab portion of the tab is placed on the pressure confirmation portion. A gap is formed between the pressure check part, which is fixed by winding and elastically deformed inward by negative pressure, and the tab pick part, and in the free state, the tab pick part and the pressure check part are in close contact with each other. It is characterized by.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below based on the illustrated embodiments.
FIG. 1 shows an easy opening can having a full opening according to an embodiment of the present invention.
The easy-open can 1 includes a bottomed cylindrical can body 2 having a can bottom (not shown) and a can lid 3 that is fastened and fixed to an upper end opening of the can body 2.
The can lid 3 includes a lid body 4 and a tab 6 for breaking the entire opening score 5 engraved in the lid body 4. The lid body 4 is a disk-shaped panel portion 41, a peripheral wall portion 42 that rises from the peripheral edge of the panel portion 41, and extends outward from the peripheral wall portion 42 to be tightened together with the winding flange 21 of the can body 2. The entire opening score 5 is formed on the outer peripheral edge of the panel portion 41 so that almost the entire surface of the panel portion 41 is opened.
[0010]
The panel portion 41 of the can lid 3 is provided with a pressure confirmation portion 7 that is elastically deformed inward by the negative pressure inside the can body 2 before opening, and that elastically recovers as soon as it opens.
The pressure confirmation unit 7 includes a circular step portion 71 that protrudes upward from the peripheral portion of the panel portion 41, and a button portion 72 that is formed to protrude from the upper surface of the step portion 71. The step portion 71 and the button portion 72 are formed concentrically, and elastically deform so that the button portion 72 is reversed downward (inside the can) with the edge of the step portion 71 as a fulcrum.
[0011]
The tab 6 has an oval shape and is fixed by a rivet portion 61 in a planned opening area surrounded by the score 5 of the panel portion 41. The tab 6 is arranged so that the longitudinal direction thereof is along the diameter line of the panel portion 41, the tab tip portion 62 that breaks the score 5 is in the vicinity of the score 5, and the knob portion 63 for causing the tab 6 is the center of the panel portion 41. Arranged on the side. The rivet portion 61 is located near the tab tip portion 62 between the tab tip portion 62 and the knob portion 63. The knob 63 has a ring shape and is provided with a finger hooking hole 63a.
[0012]
The knob 63 is disposed on the pressure checker 7.
In this example, the tip of the knob portion 63 extends to the center position of the panel portion 41, and the arcuate knob portion tip 63 b partially overlaps the button portion 72 and the step portion 71. The knob | pick part front-end | tip 63b is piled up so that the substantially center position of the small diameter button part 72 may be crossed.
The tab 6 is rivet-fixed to the periphery of the panel portion 41 that is one step lower than the pressure confirmation portion 7 in the free state, so that the knob portion 63 rides on the step portion 71 and the button portion 72 of the pressure confirmation portion 7 that is one step higher, The tip 63b of the knob is in close contact with the button part 72 without a gap.
[0013]
When the inside of the can becomes negative pressure, as shown by a two-dot chain line in the figure, the button portion 72 of the pressure confirmation portion 7 is displaced downward by the differential pressure inside and outside the can, and between the button portion 72 and the knob tip 63b. A gap g is generated. In this case, the knob 63 is supported by being in contact with the edge of the stepped portion 71, and a stable gap g is formed.
By providing the pressure confirmation unit 6 in this way, it is possible to confirm a sealing failure by visually recognizing the protruding state of the pressure confirmation unit 6, and it is also possible to confirm by a feeling of pushing the pressure confirmation unit 6 by hand.
Furthermore, when the sealing performance is good, when the tab 6 is raised and the score 5 is initially broken, the negative pressure in the can is released, and the button portion 72 of the pressure confirmation portion 7 is suddenly elastic to the original shape. It returns and pronounces “pong”, and it can be judged by ear that the sealing performance is good.
[0014]
In particular, since the tab 63 is configured so that the tab 63 is engaged with the pressure check portion 7, the protruding state of the button portion 72 of the pressure check portion 7 can be confirmed with reference to the tab knob 63, and sealing is achieved. It is easy to visually check whether the state is maintained. For example, when the button portion 72 is in contact with the tab knob portion 63 and there is no gap, the sealing performance is impaired. When the button portion 72 is separated from the tab knob portion 63 and there is a predetermined gap, Therefore, the sealing property is maintained.
[0015]
Moreover, when opening, since the clearance gap g is made under the tab knob | pick part 63, fingering property improves and it becomes easy to open. Accordingly, the gap g between the tab knobs 63 is preferably large enough to be hooked by a finger, and the shape and thickness of the pressure confirmation unit 7 are set so as to be a predetermined size according to the internal pressure of the can. The Further, since the stepped portion 71 upper surface of the button portion 72 of the pressure check unit 7 is not a recess at the time of manufacture of the can lid 3, the tab grip portion 63 to contact with other can lids during manufacture and transport of the can lid 3 etc. is hardly caught between the tab 6 and the panel portion 41, never scratched in contact with other can lids.
[0016]
Further, the pressure confirmation unit 7 may be arranged to be shifted rearward from the center as shown in FIG.
In this example, the positional relationship is set such that the knob tip 63b contacts the edge of the button portion 72. In this way, in the free state, the knob portion tip 63b is hidden by the button portion 72, and it is possible to completely prevent other can lids from entering during transportation. In addition, the visibility of poor sealing performance is improved.
The position of the pressure confirmation unit 7 may be such that the knob 63 of the tab 6 is applied to a part of the pressure confirmation unit 7, and may not be applied to the button unit 72.
[0017]
The material of the can lid 3 may be aluminum or steel. It is effective to reduce the thickness of the panel so that it can be easily elastically deformed by negative pressure. However, as the thickness of the panel is reduced, the molding pressure of the pressure confirmation unit 7 increases accordingly, so that the lid material is protected. Therefore, it is desirable to laminate a PET (PET) film.
[0018]
FIG. 3A shows an example of a mold for the pressure confirmation part of the can lid.
That is, the upper punch 103 and the lower punch 104 for forming the pressure confirmation portion 7 are assembled at the center of the upper die 101 and the lower die 102.
The upper punch 103 includes an upper punch main body portion 105 having an annular pressure surface and a guide portion 106 extending above the upper punch main body portion 105, and the pressure surface of the upper punch main body portion 105 is the upper die 101. Recessed by a predetermined dimension δ with respect to the mold closing surface 101a. The pressurizing surface of the upper punch main body 105 forms the upper surface of the stepped portion 71 of the pressure confirming unit 7, and is a spacer interposed between the back surface 103a of the upper punch main body 103 and the back end surface 101b of the upper die 101. The overhang amount can be adjusted by 107.
[0019]
On the other hand, the lower punch 104 includes a lower punch body 108 having an annular pressure surface facing the upper punch body 105, a guide 112 extending below the lower punch body 108, and a lower punch body 108. And a core 109 to be inserted into the central recess.
The lower die 102 is an annular member that is slidably fitted to a fixed base portion 110 at the center, and a lower punch 104 is attached to the fixed base portion 110. The pressure surface on the upper surface of the lower punch main body 108 protrudes from the mold closing surface 102a of the lower mold 102 by a predetermined dimension when the lower mold 102 is at the lowest end position.
The stepped portion 71 is formed by projecting upward while pressing the panel portion of the intermediate molded body 3A from above and below by the pressing surface on the upper surface of the lower punch body portion 108 and the pressing surface on the lower surface of the upper punch body portion 103.
[0020]
Using this mold, the pressure confirmation part is molded as follows.
First, the can lid intermediate molded body 3 </ b> A before the pressure confirmation part molding is placed on the lower mold 102. The intermediate molded body 3A is positioned by a curl support portion 102b that supports the flange-shaped curl portion 43 of the can lid 3.
When the upper die 101 is lowered, the pressing surface of the upper die 101 comes into contact with the flat surface portion around the panel portion of the intermediate molded body 3A and is sandwiched between the upper die 101 and the lower die 102, and further lowered in this state. As a result, the panel portion of the intermediate molded body 3A is pressed against the upper surfaces of the lower punch main body portion 108 and the core 109, and the inclined portion of the stepped portion 71 is formed.
[0021]
In the above mold, the upper punch 103 is configured as a tool steel pad. However, as shown in FIG. 3B, the pressure surface of the upper punch 103 is configured by a flexible urethane pad 111, and the pressure is increased. The shape of the confirmation unit 7 may be determined by the shape of the upper surface of the lower punch 104.
In this case, a spacer 112 is provided between the lower end surface of the core 109 and the bottom surface 108a of the central recess of the lower punch main body 108 so that the amount of protrusion from the upper surface of the lower punch main body 108 on the core 109 can be adjusted. By this core 109, the button part 72 of the pressure confirmation part 7 is molded.
The molding of the pressure check part is performed before the tab 6 is attached, and the tab 6 is attached after the pressure check part is formed.
[0025]
In each of the above embodiments, the pressure confirmation portion has a two-stage concentric circular shape, but is not limited to this shape. In short, it is elastically deformed by the negative pressure inside the can and is depressed and elastic when opened. Any structure that recovers and sounds is acceptable.
Moreover, although the can lid having the entire surface opening has been described, it is needless to say that the present invention can be applied to a lid for partial opening.
[0026]
【The invention's effect】
As described above, according to the present invention, it is possible to easily confirm a sealing failure such as a score failure by providing a pressure confirmation portion on the can lid.
[0027]
Further, since it rests on the pressure check portion the knob portion of the tab, the tab and by looking at the distance between the pressure check unit, i.e. by observing the projected state of the pressure check unit relative to the tab grip portion This facilitates visual recognition of whether or not the sealing is maintained.
[0028]
In addition, when the opening is made, a gap is formed under the knob portion, so that the finger holdability is improved and the opening becomes easy. Furthermore, the pressure check unit at the time of manufacture of the can lids, since no raised tabs in close contact with the tab knob portion, the other of the can lids during manufacture and transport of the can lid is not easily caught between the tab and the panel, There is no risk that the tabs or recesses come into contact with other lids and are damaged.
[Brief description of the drawings]
FIG. 1 shows a can lid of an easy-open can according to an embodiment of the present invention. FIG. 1 (A) is a plan view, and FIG. 1 (B) is a cross-sectional view taken along line BB of FIG. It is a line expanded sectional view.
2 shows a modified example of the can lid of FIG. 1, FIG. 2 (A) is a plan view, and FIG. 2 (B) is an enlarged sectional view taken along line BB of FIG. 2 (A). .
3A is a cross-sectional view showing an example of a mold for molding the pressure confirmation portion of the can lid of FIG. 1, showing a mold open state on the left half and a mold closed state on the right half; FIG. 3B is a cross-sectional view showing a modification of the mold shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Easy opening can 2 Can main body 3 Can lid 4 Lid main body 41 Panel part 6 Tab 63 Knob part 63b Knob part tip 5 Score 7 Pressure confirmation part 71 Step part, 72 Button part

Claims (4)

A can body, and a can lid that is fastened and fixed to the upper end opening of the can body. The can lid is provided with a score surrounding the planned opening area and a tab for breaking the score. In easy opening cans,
Before the opening, the can lid is elastically deformed inward by the negative pressure inside the can body, and provided with a pressure confirmation part that sounds elastically at the same time as opening,
The tab portion of the tab is attached to be over the pressure confirmation portion,
It is characterized in that a gap is formed between the pressure check part that is fixed by winding and elastically deformed inward by negative pressure and the tab pick part, and the tab pick part and the pressure check part are in close contact in a free state. Easy opening can. The pressure confirmation part includes a step part protruding upward from the peripheral part of the panel part of the can lid, and a button part formed to protrude from the upper surface of the step part. The easy-open can according to claim 1, wherein the can is in close contact with the button portion without any gap . The pressure confirmation part has a step part that protrudes upward from the peripheral part of the panel part of the can lid, and a button part that is formed to protrude on the upper surface of the step part. 2. The easy-open can according to claim 1, wherein the can is set in a positional relationship so as to contact the edge of the button portion . In a can lid of an easy-open can comprising: a lid body having a score surrounding a planned opening area; and a tab attached to the lid body and breaking the score.
The lid body is elastically deformed inside by the negative pressure inside the can body before opening, and is provided with a pressure confirmation portion that is elastically restored at the same time as opening,
The tab portion of the tab is attached to be over the pressure confirmation portion,
It is characterized in that a gap is formed between the pressure check part that is fixed by winding and elastically deformed inward by negative pressure and the tab pick part, and the tab pick part and the pressure check part are in close contact in a free state. Easy-to-open can lid.

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