JP2002160733A - Easily openable can, and can lid and can bottom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easily openable can and its can lid and can bottom wherein whether sealing is surely conducted or not is easily confirmed visually from the outside, hermetic condition can be confirmed by sound when it is opened, which has no problem in damage and a transportability when it is manufactured, and has an excellent finger hooking property. SOLUTION: In this easily openable can, a pressure confirmation part 7 which is elastically deformed inward by a negative pressure of the inside part of a can body 2 before it is opened and is elastically restored and sounds at the time when it is opened is provided in a can lid 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an easy-open can having a partial opening or an entire opening, and more particularly to an easy-open can having a pressure checking portion, a can lid and a can bottom.

[0002]

2. Description of the Related Art In recent years, food cans (for example, agricultural and marine products,
Even processed foods, sauces, soups, etc.) are required to have easy opening like a beverage can, and an easy opening can lid is attached. Some of these easy-to-open food cans maintain the internal pressure of the can at a negative pressure. This negative pressure can is kept hermetically sealed until the consumer opens it, and is kept in a negative pressure state at the distribution stage.

[0003]

However, in the case of easy-open cans, since scores are formed on the can lid, if the retort sterilization or handling in the distribution stage is not appropriate, the score will crack and the seal will be closed. The property may be impaired. However, the conventional easy-open can has no means for checking whether the internal pressure is appropriate, and it is difficult to determine even if there is a poor sealing property.

On the other hand, easy-open can lids are required to be easy to open, but especially in negative pressure cans, since the can lid is warped inward as a whole, the tabs are inferior to fingers and tend to be difficult to open. was there. In order to cope with this, countermeasures such as providing a concave portion below the tab portion of the tab, and providing a convex portion on the panel portion below the tab to float the tab are taken. However, if the depth of the concave portion or the convex portion is increased to increase the distance between the tab and the panel portion, another can lid or the like may be stuck between the tab and the panel during manufacturing and transport 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.
It is easy to see from the outside whether sealing is done securely, and it is possible to confirm the sealing performance by pronouncing when opening, and there is no damage or transportability during manufacturing, and it is easy to open with good finger grip An object of the present invention is to provide an open can, its can lid and a can bottom.

[0006]

According to the present invention, there is provided a can body comprising: a can body; and a can lid which is fixedly wound around an upper end opening of the can body. In the easy-open can provided with a score surrounding the expected opening area on the lid and a tab for breaking the score,
The can lid is provided with a pressure check unit which is elastically deformed inward by the negative pressure inside the can main body before opening and is elastically restored at the same time as opening. Further, it is preferable that the tab of the tab is attached so as to be placed on the pressure checking unit.

[0007] A can lid of an easy-open can according to the present invention includes a lid body having a score surrounding a region to be opened, and a tab attached to the lid body and breaking the score. In the above, the lid body is provided with a pressure confirming portion which is elastically deformed inward by a negative pressure inside the can body before opening, and is elastically restored at the same time as opening to produce sound.

Further, the can bottom of the easy-opening can of the present invention is provided on the bottom of the can bottom of the easy-opening can provided with the easy-opening can lid. It is characterized in that a pressure confirming portion is provided which is elastically deformed and opened and elastically restored at the same time as opening.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment. FIG. 1 shows an easy-open can having an entire opening according to an embodiment of the present invention. This easy opening can 1
Is a can body 2 having a bottomed cylindrical shape having a can bottom (not shown), and a can lid 3 which is fixedly fastened to an opening at an upper end of the can body 2.
And The can lid 3 has a lid body 4 and tabs 6 for breaking the score 5 for full opening formed in the lid body 4.
And The lid body 4 has a disk-shaped panel portion 41.
And a peripheral wall portion 42 rising from the peripheral edge of the panel portion 41
Extending outward from the peripheral wall portion 42 to extend the can body 2.
And a winding curl portion 43 that is tightened together with the tightening flange 21.
It is formed on the outer peripheral edge of the panel portion 41, and almost the entire surface of the panel portion 41 is opened.

The panel portion 41 of the can lid 3 is provided with a pressure check portion 7 which is elastically deformed inward by the negative pressure inside the can main body 2 before opening, and returns elastically at the same time as opening. ing. The pressure checking unit 7 includes a circular step 71 protruding above the peripheral part of the panel 41, and a button part 72 formed on the upper surface of the step 71. The step portion 71 and the button portion 72 are formed concentrically, and are elastically deformed so that the button portion 72 is inverted downward (inside of the can) with the edge of the step portion 71 as a fulcrum.

The tab 6 has an elliptical shape and is fixed by a rivet 61 to an opening area surrounded by the score 5 of the panel 41. The tab 6 is disposed so that its longitudinal direction is along the diameter line of the panel portion 41, the tab tip portion 62 for breaking the score 5 is located near the score 5, and the knob 63 for causing the tab 6 is located at the center of the panel portion 41. Located on the side.
The rivet portion 61 is located closer to the tab tip 62 between the tab tip 62 and the knob 63. The knob 63 has a ring shape and is provided with a finger hole 63a.

The knob 63 is disposed so as to cover the pressure checking unit 7. In this example, the tip of the knob 63 extends to the center position of the panel 41, and the arc-shaped tip 63 b of the arc partially overlaps the button 72 and the step 71. The knob distal end 63b is overlapped so as to substantially cross the center of the small-diameter button 72. Tab 6
Since the rivet is fixed to the peripheral portion of the panel portion 41 which is one step lower than the pressure confirmation portion 7 in the free state, the knob portion 63 rides on the step portion 71 and the button portion 72 of the pressure confirmation portion 7 which is one step higher, and the tip of the arc-shaped knob portion. 63b is in close contact with the button 72 without any gap.

When the inside of the can becomes a negative pressure, the button 72 of the pressure confirming unit 7 is displaced downward due to the differential pressure between the inside and the outside of the can, as indicated by a two-dot chain line in the figure, and the button 72 and the tip 63b of the knob.
And a gap g is generated between them. In this case, the knob 63 is supported in contact with the edge of the step 71, and a stable gap g is formed. By providing the pressure checking unit 6 in this manner, it is possible to check the sealing property failure by visually checking the protruding state of the pressure checking unit 6, and it is also possible to check by touching the pressure checking unit 6 by hand. Furthermore, when the sealing property is good, when the tab 6 is caused and the score 5 is initially broken, the negative pressure in the can is released and the button 72 of the pressure check section 7 is rapidly elastically restored to the original shape. I came back and pronounced pong,
It can be judged by ear that the sealing property is good.

In particular, the knob 63 of the tab 6 is
, The projected state of the button portion 72 of the pressure confirming portion 7 can be confirmed based on the tab knob 63, and it is easy to visually recognize whether or not the sealed state is maintained. . For example, when the button 72 is in contact with the tab knob 63 and there is no gap, the sealing property is impaired. When the button 72 is separated from the tab knob 63 and there is a predetermined gap, there is no gap. Thus, the hermeticity is maintained.

Further, when the opening is formed, the gap g is formed below the tab knob 63, so that the finger can be easily gripped and the opening is facilitated. Therefore, it is preferable that the gap g between the tab knobs 63 is large enough to be hooked by a finger, and the shape and thickness of the pressure checking unit 7 are set so as to have a predetermined size according to the internal pressure of the can. You. Further, since the button 72 on the upper surface of the step 71 of the pressure checking unit 7 is not concave when the can lid 3 is manufactured, the button 72 contacts the tab knob 63,
Alternatively, since the interval is small, another can lid or the like is unlikely to be caught between the tab 6 and the panel portion 41 during the production and transport of the can lid 3, and does not come into contact with the other can lid and is not damaged.

Further, the pressure confirmation section 7 may not be provided at the center, but 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 end portion 63b contacts the edge of the button portion 72. In this way, in the free state, the knob end portion 63b is hidden by the button portion 72, and it is possible to completely prevent another can lid from entering during transportation. Further, the visibility of the poor sealing property is improved. The position of the pressure checking unit 7 may be such that the knob 63 of the tab 6 covers a part of the pressure checking unit 7, and does not have to be on the button 72.

The material of the can lid 3 may be any of aluminum-based and steel-based materials. As for the thickness of the panel, it is effective to reduce the thickness of the panel in order to facilitate elastic deformation by negative pressure.
Therefore, it is desirable to laminate a PET (PET) film to protect the lid material because the molding pressure of the PET becomes large.

FIG. 3 (A) shows an example of a mold for the pressure checking portion of the can lid. That is, the upper die 101,
At the center of the lower die 102, an upper punch 103 and a lower punch 104 for forming the pressure checking portion 7 are assembled. The upper punch 103 has an upper punch body 105 having an annular pressing surface, and a guide portion 106 extending above the upper punch body 105. The pressing surface of the upper punch body 105 is It is retracted upward by a predetermined dimension δ with respect to the mold closing surface 101a. Upper punch body 105
Press surface forms the upper surface of the step portion 71 of the pressure checking portion 7, and the back surface 103a of the upper punch body 103 and the upper die 10
Spacer 107 interposed between the inner end face 101b and the inner end face 101b
The overhang amount can be adjusted.

On the other hand, the lower punch 104 has a lower punch main body 108 having an annular pressing surface facing the upper punch main body 105, a guide portion 112 extending below the lower punch main body 108, and a lower punch 104. A core 109 inserted into a central recess of the main body 108. Lower mold 102
Is an annular member, which is slidably fitted to the central fixed base 110, and the lower punch 104 is mounted on the fixed base 110. The pressing surface on the upper surface of the lower punch body 108 is
When the lower mold 102 is at the lowermost position, the mold closing surface 1 of the lower mold 102
02a protrudes by a predetermined dimension. The pressurizing surface on the upper surface of the lower punch main body 108 and the pressurizing surface on the lower surface of the upper punch main body 103 cause the panel portion of the intermediate molded body 3A to protrude upward while being pressed from above and below to form the step 71.

Using this molding die, a pressure checking section is molded as follows. First, the can lid intermediate formed body 3A before forming the pressure checking portion is placed on the lower mold 102. This intermediate molded body 3
The position of A is determined by the curl support portion 102b that supports the flange-shaped curl portion 43 of the can lid 3. When the upper mold 101 is lowered, the pressing surface of the upper mold 101 comes into contact with the flat surface around the panel portion of the intermediate molded body 3A, and the upper mold 1
01 and the lower mold 102, and when further lowered in this state, the panel part of the intermediate molded body 3A is pressed against the upper surfaces of the lower punch body 108 and the core 109, and the inclined part of the step 71 is formed. You.

In the above-mentioned mold, the upper punch 103 is formed as a tool steel pad. As shown in FIG. 3B, the pressing surface of the upper punch 103 is formed by a flexible urethane pad 111. However, the shape of the pressure checking unit 7 may be determined by the shape of the upper surface of the lower punch 104. In this case, the lower end surface of the core 109 and the lower punch body 10
A spacer 112 is provided between the upper surface of the core 109 and the bottom surface 108a of the recess 8 so that the amount of protrusion of the upper surface of the core 109 from the upper surface of the lower punch body 108 can be adjusted. The button part 72 of the pressure confirmation part 7 is molded by the core 109. The above-described pressure confirmation section is formed before the tab 6 is attached, and the tab 6 is attached after the pressure confirmation section is formed.

In the above embodiment, the example in which the pressure checking section 7 is provided on the can lid 3 has been described, but the pressure checking section 7 may be provided on the bottom of the can. FIG. 4 shows a can bottom of the easy opening can according to the embodiment of the present invention. That is, the can bottom 20
Reference numeral 3 denotes a can body 2 which is fixedly fastened to a lower end opening of a can body 201 of an easy-opening can, and an easy-open can lid (not shown) is fixedly fastened to an upper end opening of the can body 201. You.

The can bottom body 204 includes a disc-shaped panel portion 24.
1, a peripheral wall portion 242 hanging downward from a peripheral edge of the panel portion 241, a winding curl portion 243 extending outward from the peripheral wall portion 242 and being wound together with the winding flange 221 of the can body 201; The panel portion 241 is provided with a pressure confirmation portion 207 that elastically deforms inward by the negative pressure inside the can before opening, and returns elastically at the same time as the opening.

The structure of the pressure checking portion 207 is the same as that provided on the can lid 3, and has a circular step 271 projecting downward from the periphery of the panel section 41, and a projection formed on the lower surface of the step 271. Button portion 272 to be operated. The step 271 and the button 272 are formed concentrically.
The button portion 272 is elastically displaced upward (inside of the can) using the edge of the step portion 271 as a fulcrum. Although the illustrated example illustrates a three-piece can bottom, the present invention can be applied to a two-piece can bottom in which the can bottom and the can body are integrally formed.

Further, in each of the above embodiments, the shape of the pressure confirming portion is a two-stage concentric shape. However, the shape is not limited to this shape. Any structure may be used as long as it is elastically restored and sounds when opened. In addition, although the can lid having a full opening has been described, it goes without saying that the present invention can be applied to a lid for a partial opening.

[0026]

As described above, according to the present invention, by providing the pressure check section on the can lid, it is possible to easily check poor sealing properties such as score breakage.

Further, if the tab of the tab is made to engage with the pressure confirming portion, the distance between the tab and the pressure confirming portion can be seen, that is, the projecting state of the pressure confirming portion. Is observed with reference to the tab knob, so that it is easy to visually recognize whether or not the sealed state is maintained.

Further, when the opening is made, a gap is formed below the knob portion, so that the finger can be easily gripped and the opening is made easier. Furthermore, since the pressure check section is not concave during the manufacture of the can lid, the gap between the tab knob and the tab is narrow, and the tab does not rise. And there is no possibility that the tabs or the recesses may come into contact with other lids and be damaged.

Further, if the pressure sensor is provided at the bottom of the can, pressure can be checked without providing a pressure checking section on the can lid.

[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 BB in FIG. 1 (A). It is a line expanded sectional view.

2 shows a modification 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). .

FIG. 3A is a cross-sectional view showing an example of a molding die for molding the pressure checking portion of the can lid of FIG. 1, showing a mold opened state in a left half and a mold closed state in a right half; FIG. 3B is a cross-sectional view showing a modified example of the mold shown in FIG.

FIG. 4 shows the bottom of the easy-opening can according to the embodiment of the present invention. FIG. 4 (A) is a bottom view, and FIG. 4 (B) is BB in FIG. 4 (A). It is a line expanded sectional view.

[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 tip end 5 Score 7 Pressure check part 71 step part, 72 Button part 203 Can bottom 207 Pressure check part 271 step part, 272 Button section

Claims (5)

[Claims] 1. A can body comprising: a can body; and a can lid wound around and fixed to an upper end opening of the can body, wherein the can lid is provided with a score surrounding a region to be opened and the score is broken. In the easy opening can provided with the tab of the above, the can lid is provided with a pressure checking portion which is elastically deformed inward by the negative pressure inside the can main body before opening and is elastically restored at the same time as opening. And easy opening can. 2. The easy-opening can according to claim 1, wherein the tab of the tab is attached so as to hang over the pressure checking part. 3. The easy-opening can according to claim 1, wherein the pressure checking section is provided on the bottom of the can instead of the can lid. 4. A can lid for an easy-open can having a lid body having a score surrounding an opening area and a tab attached to the lid body and breaking the score, wherein the lid body has Is a can lid for an easy opening can, characterized in that a pressure check portion is provided which is elastically deformed inward due to negative pressure inside the can body and is opened and elastically restored at the same time. 5. A can bottom of an easy-open can having an easy-open can lid, wherein the can bottom body is elastically deformed inward by a negative pressure inside the can body before opening, and elastically returns simultaneously with opening. A can bottom of an easy-open can characterized by providing a pressure checking unit for sounding.