JPH0536307B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention reduces tearing force after initial opening,
This invention relates to a vent-type Fluid Easy Open can lid with improved can opening performance. [Prior Art] Easy-open can lids can be opened using the pulling force of a fingertip, without requiring any tools such as a can opener. Because of this convenience, they are now widely used as food cans, carbonated beverage cans, beer cans, etc. These easy-open can lids are classified into partial-open can lids that open a portion of the can lid (hereinafter referred to as partial easy-open can lids) and full easy-open can lids that open the entire can lid. Ru. With partial easy-open can lids, when the can lid is opened by pulling the tension knob fixed to the opening piece, the apex of the opening piece on one side of the tension knob is pulled and lifted, and opening begins. is,
The opening is completed by continuing to pull the tension tab further. On the other hand, in the Flu Easy Open can lid, the tip of the opening piece to which the tension knob is fixed is once bent inside the can body.
Opening begins. Then, by pulling up this opening piece, the opening operation is continued and the entire can body is opened. In this way, the initial opening format is different between the partial easy-open can lid and the full easy-open can lid. In addition, with Flu Easy-Open can lids, the radius of curvature of the apex shape on the side where opening starts is larger than that of Partial Easy-Open can lids, making it difficult for stress to concentrate at the beginning of opening, resulting in poor initial opening performance. Inferior. Since the opening piece of a full easy-open can lid is larger than that of a partial easy-open can lid, the tearing force after initial opening is much greater. For this reason, the full easy-open can lid has inferior can opening performance compared to the partial easy-open can lid. Various studies have been conducted to improve the opening performance of this Fluid Easy Open can lid.
For example, by forming the breakage score on the line of the opening score carved on the periphery of the can lid, the remaining thickness of this part can be made smaller than the remaining thickness of the opening score, and the initial It is proposed in Japanese Utility Model Application Publication No. 57-43239 to make it a destructive part. In this way, by thinning a portion of the opening score line, initial can opening performance can be improved. In addition, in the publication of JP-A No. 52-94291,
Initial opening performance is improved by defining the distance between the nose and the closest opening score. These measures facilitate the task of initiating the opening of the can lid by triggering the pull tab. However, no effective means has been proposed so far for reducing the tearing force after the initial opening. [Problem to be solved by the invention] By the way, the ease or difficulty of opening that a person feels when opening an easy-open can lid is determined by the initial opening performance at the beginning of opening, as well as the initial opening performance. It is also greatly influenced by the amount of force used when tearing the can lid from the can body. For example, even if a can has excellent initial opening properties, if the tearing force is large, the impact and vibrations generated when tearing the can lid will be transmitted to the can body, causing the contents to spill out. It's possible. In particular, in the case of Fluid Easy Open can lids, the opening piece that is separated from the can body is large, so the tearing force is large. Therefore, an object of the present invention is to improve the openability of Flueasy-open can lids by reducing this tearing force. [Means and effects for solving the problems] In order to achieve the object, the Flueasy-Open can lid of the present invention has an opening score carved on the periphery of the can lid, and an opening score in the vicinity of the scored opening. In a flue-easy-open can lid in which a vent score is carved on the side opposite to the opening score with respect to the fixed part of the tension knob provided on the lid, beads having a component along the tearing direction are formed on both sides of the vent score. It is characterized by Here, the distance a in the tearing direction X between the upper end of the vent score and the starting end of the bead is 4
It is preferable to make it less than mm. Further, the end portion of the bead is preferably provided within a range of 25 mm or less from the upper end portion of the vent score in the tearing direction X. Furthermore, the bead can be formed on both sides of the vent score with an angle θ between −10 and 60 degrees with respect to the tear direction X. FIG. 1 shows a vent-type flu easy-open can lid according to the present invention. An opening score 2 is engraved on the periphery of the can lid 1. A fixing part 4 in which a tension knob 3 is attached to the can lid 1 is formed near a part of the opening score 2.
A vent score 5 is carved on the side opposite to the opening score 2 with respect to the fixed portion 4. By triggering this tension knob 3,
First, the part of the vent score 5 closest to the fixed part 4 is broken, and the vertex of the opening score 2 closest to the fixed part 4 becomes the opening starting point 6, and there is a gap between the vent score 5 and the opening score 2. certain opening piece 7
The initial opening is completed by folding the part inside the can and fully raising the pull tab 3. In the present invention, beads 8 having components along the tearing direction X are formed symmetrically on both sides of the vent score 5 with the fixed portion 4 as the center. By this bead 8, the opening piece 7 between both sides of the vent score 5 of the opening piece 7 and the opening score 2
The bending rigidity increases, and it is bent at the bending line 9 indicated by the dashed line. Therefore, the force when pulling the tension knob 3 is concentrated and transmitted to the opening score 2, and the opening is performed over a wide range. As a result, the initial opening width W becomes large, and at the same time, the length of the arm for applying a bending moment at the time of tearing can be ensured. On the other hand, when the bead 8 is not formed, the rigidity of the opening piece 7 between the opening score 2 and the vent score 5 is the weakest, so as shown in FIG. Bending line 9 shown by
It can be bent at part a. As a result, the initial opening width W becomes smaller than that shown in FIG. 1, and the arm length for applying a bending moment cannot be ensured. The size of the initial opening width W has a large effect on the subsequent tearing force of the opening piece 7. That is, when tearing the opening piece 7 from the can body after the initial opening, the larger the initial opening width W, the longer the distance along the tearing direction becomes longer, and the bending moment that is attempted to be caused by bending the opening piece 7 becomes larger. Thereby, the tearing force required to separate the opening pieces 7 can be reduced. At this time, the distance a between the upper end of the vent score 5 and the starting end 8a of the bead 8 along the tearing direction
is preferably 4 mm or less. Moreover, it is preferable that the distance b between the upper end of the vent score 5 and the terminal end 8b of the bead 8 along the tearing direction X is 25 mm or less. Here, the distance to the upper end of the vent score refers to the distance from the flat part of the vent score in FIGS. 1 and 2, and the distance from 5a in FIG. 3. When the distance a exceeds 4 mm or the distance b exceeds 25 mm, the tension knob 3 is triggered to break the vent score 5, and the apex of the opening score 2 closest to the fixed part 4 is opened to start opening. At this time, even though the bead is attached, the bead 8 is bent and the initial opening width W cannot be increased. In addition, in order to stably exhibit the effects of the present invention, it is preferable that the lower limit of the distance b is 3 mm. Furthermore, the angle θ between the bead 8 and the tearing direction
is preferably in the range of -10 to 60 degrees. However, if the angle θ is negative, the bent score is 5.
This means that the beads 8 are provided on the opening piece 7 at an angle of inclination such that they intersect on the downstream side of the tearing direction X. When this angle θ exceeds 60 degrees, the effect of increasing the rigidity of the opening piece 7 portion between the vent score 5 and the opening score 2 is lost, and as a result, the initial opening width W cannot be increased. Further, when the angle θ becomes more negative than −10 degrees, the effect of stably widening the initial opening width W is lost. The material of the can lid to which the present invention is applied is not particularly limited, and the following materials can be used as well as the commonly used tin plate and aluminum plate. (1) Non-ferrous metal materials such as iron and iron alloys, or aluminum and aluminum alloys (2) Metal materials that have undergone surface treatment such as plating or painting on the metal materials in (1) above (3) (1) and / or a composite metal material made by bonding an organic material such as a resin to the metal material in (2) in a layered manner (4) a composite metal material in which dissimilar metal materials in (1) and/or (2) above are bonded in a layered manner; , the flueasy open can lid of the present invention is
It can also be applied to a safety type can lid that prevents injury from the cut end of the can and the opened opening piece. [Example] As the can lid 1, a 301 type (31/16 inch) Flueasy Open can lid was manufactured using T-4 tin plate with a plate thickness of 0.23 mm. The can lid is engraved with a vent score 5 with a remaining score thickness of 70 μm and an opening score 2 with a remaining score thickness of 50 μm. Furthermore, a bead 8 having a component along the tear direction X under the conditions shown in Table 1 was given a vent score of 5.
formed on both sides. These can lids 1 and conventional can lids without beads were opened and the initial opening width W and tearing force were investigated, and the results are shown in Table 1.

〔Effect of the invention〕

As explained above, in a vent-type Fluid Easy-Open can lid, by forming beads on both sides of the vent score that have a component along the tearing direction, it separates from the can body when the pull tab is pulled. The opening width of the initial opening portion of the opening piece can be increased. Moreover, this initial opening width can be maintained at a stable value by regulating the positions of the starting end and the ending end of the bead. As a result, a wide initial opening width is always obtained, resulting in a flue-easy-open can lid with excellent can opening performance.

[Brief explanation of drawings]

FIG. 1 shows a vent type fluid easy-open can lid of the present invention, FIG. 2 shows a comparative example without a bead, and FIG. 3 shows an enlarged view with a different vent score.

Claims (1)

[Scope of Claims] 1. An opening score is engraved on the periphery of the can lid, and a vent score is engraved on the side opposite to the opening score with respect to the fixed portion of the tension knob provided near the opening score. A vent-type Flueasy-open can lid with excellent can-opening properties, characterized in that beads having a component along the tearing direction are formed on both sides of the vent score. 2. Tear direction X between the upper end of the vent score and the starting end of the bead as described in claim 1
A vent-type flue-easy-open can lid with excellent can-opening properties, characterized in that the distance a between the can and the can is 4 mm or less. 3. A vent-type fluid easy open with excellent can opening performance, characterized in that the end of the bead as described in claim 1 is provided within a range of 25 mm or less from the upper end of the vent score in the tearing direction X. Can lid. 4. A vent-type fluid easy open with excellent can opening properties, characterized in that the bead according to claim 1 is formed with an angle θ between -10 and 60 degrees with respect to the tearing direction X. Can lid.