JPS63281953A - Easy open can lid excellent in can opening property - Google Patents

Abstract

PURPOSE:To smoothly open a can by lowering both of initial can opening force and initial tearing force, by providing a machining part locally weakening the rigidity in an opening piece tearing direction and a single or plural machining parts lowering bending rigidity to an opening piece. CONSTITUTION:The machining part 8 provided to the place close to the fixing part 5 of a non-opening piece part 6 is formed by locally reducing the non- opening piece part in a V-shape, a U-shape or a groove shape. The machining part 8 is provided to the region shown by a shaded part surrounded by the straight line 12 passing the center of the fixing part 5 and crossing a tearing direction 9 at a right angle, straight lines 10 starting the intersecting point 13 with a score 2 and inclined by + or -15 deg. in the tearing direction 9 with respect to the straight line 12 to extend to the left and right, the straight lines 11 passing the apex 3a of an opening piece 3 and inclined in the direction opposite to the tearing direction with respect to the straight line crossing the tearing direction 9 at a right angle and extending from the apex part 3a of the opening piece 3 to the left and right, and the score 2. As a result, the can opening force is concentrated to an opening start point and the initial can opening force is lowered to a large extent and a can opening property becomes well.

Description

DETAILED DESCRIPTION OF THE INVENTION [Second Industrial Fields of Application] The present invention relates to a partial opening lid (hereinafter referred to as an easy-open can lid) whose opening piece can be opened and torn as desired with a small force.

[Conventional technology]

The easy-open can lid allows the can lid to be opened using the pulling force of the fingertips without the need for tools such as a can opener. Taking advantage of this advantage, it is now used in a wide range of applications such as food cans, carbonated beverage cans, and beer cans.

In order to improve the openability of this easy-open can lid, various proposals regarding can lids have been made. For example, an easy-open can lid has been proposed in JP-A-58-149251, which has a main score engraved on the can lid and an auxiliary score adjacent to the main score.

In addition, Japanese Patent Publication No. 49-40679 discloses that an auxiliary part extending outward from a part of the main score of the area where the tension knob is first broken by pulling it up is approximately parallel to the longitudinal axis of the tension knob. An easy-open can lid with a score has been proposed. Even if the main score is broken by pulling up the tension picker, this auxiliary score will not be broken. However, by providing the auxiliary score perpendicularly to the portion of the main score that is to be broken first, opening becomes easier and a certain improvement in can opening performance is observed.

[Problem that the invention seeks to solve]

The difficulty a person feels when opening an easy-open can lid is greatly influenced by the amount of force applied at the beginning of opening and the subsequent tearing force. For example, if the initial can opening force is low and the subsequent tearing force is low, the easy-open can lid will be much easier to open. However, when using the above-mentioned auxiliary score, although the desired can-opening force is slightly reduced, it is still far from being sufficient.

Therefore, in order to facilitate the opening of this easy-open can lid, the present inventors installed a horizontal auxiliary score on the non-opening side of the lid body adjacent to the peripheral part of the fixed part provided with the tension knob via the score. He developed an engraved version and filed an application as Utility Model Application No. 1983-40595. .

An object of the present invention is to provide an easy-open can lid that allows flexible can opening by further reducing the intended opening force of the easy-open can lid and the subsequent tearing force of the opening piece. shall be.

[Means for solving problems]

In order to achieve the purpose of the easy-open can lid of the present invention, the easy-open can lid has an opening piece surrounded by scores and has a tension knob fixed thereto, and is machined to locally weaken the rigidity in the tearing direction of the opening piece. The opening piece is characterized in that a portion is provided on one side of the non-opening portion near the fixed portion, and one or more machined portions for reducing bending rigidity are provided on the opening piece.

Here, the machined part provided on one side of the non-opening part is defined by starting from an area extending from a straight line passing through the center point of the fixed part and perpendicular to the tearing direction of the opening piece to the apex of the opening piece, and perpendicular to the tearing direction. It can be opened in the direction of the arrow and extended horizontally within a range of ±15 degrees either continuously or discontinuously. This machined portion includes a thin wall portion formed by machining a non-opening side portion into a V-shape, a U-shape, or a groove shape.

On the other hand, the machined part provided on the opening piece includes a continuous or discontinuous linear, two-curved, V-shaped or inverted V-shaped score along the direction crossing the tearing direction of the opening piece, and a thin wall. There are parts, wavy parts, beads, etc. Alternatively, it may be provided in the opening piece as a single thin wall portion or a plurality of depressions.

Furthermore, it is preferable that the distance between the apex of the opening piece and the outer periphery of the fixed portion of the tension knob piece be 0.4 square inches or less.

[Effect]

The present inventors conducted various experiments in order to develop an easy-open can lid that lowers the initial can opening force and allows the subsequent tearing of the opening piece to be performed flexibly with a small force.As a result, In an easy-open can lid having an opening piece surrounded by a score and having a tension knob fixed to it, a machined part that locally weakens the rigidity of the opening piece in the tearing direction is provided on one side of the non-opening part near the fixed part of the tension knob. form,
In addition, if machined parts that reduce the bending rigidity of the opening piece are formed at predetermined intervals on the opening piece, when the tension knob is pulled up to start opening, the initial opening force is significantly reduced compared to conventional cans, and the opening force continues to increase. During the tearing process of the apertured piece, the apertured piece continuously bends, and the tearing force decreases. In this way, both the initial can-opening force and the tearing force are reduced, so that the can-opening operation can be performed smoothly. The present invention was completed based on this knowledge.

〔Example〕

Hereinafter, the features of the present invention will be specifically explained using examples with reference to the drawings.

FIG. 1 shows an easy-open can lid in one embodiment of the present invention.

A score 2 is engraved on this easy-open can lid 1, and a portion surrounded by the score 2 becomes an opening piece 3. A protrusion is press-molded in a part of this opening piece 3, and after fitting the hole of the tension knob piece 4 into the protrusion, the protrusion is caulked to form a fixed part 5 to which the tension knob piece 4 is attached. are doing. Note that, along with the score 2, an auxiliary score 7 can also be provided on the non-opening side portion 6 of the easy-open can lid 1.

In this embodiment, when pulling up the tension knob 4 to start opening at a location close to the fixed part 5 of the non-opening side portion 6, the rigidity of the opening piece 3 in the tearing direction 9 is locally weakened. A machining section 8 is provided for this purpose.

FIG. 2 shows several examples of the cross-sectional shape of this machined part 8. The non-opening side portion 6 is locally thinned to have a V-shape in FIG. 2A, a U-shape in FIG. 1C, and a groove shape in FIG. As a result, the rigidity of the non-opening side portion 6 around the fixed portion 5 is reduced.

, and the cross-sectional shape of the machined part 8 in this example is as follows:
Various other shapes can be adopted without being restricted to that shown in FIG. For example, the cross-sectional shape may be any shape as long as it can be locally thinned by combining these, such as a groove-like shape with a V-shape added thereto. Further, it is preferable that the residual thickness t of 8 from the mechanical part is equal to or greater than the residual thickness of score 2.

The position where the machined portion 8 is provided on the non-opening half-section 6 and the direction in which the machined section 8 is carved are important in reducing the rigidity in the tearing direction 9 of the non-opening half-section 6 near the fixed portion 5.

First, the position where the machined part 8 is provided is set in the range surrounded by the slope lines 10 and 11, as shown in FIG. This inclined line 10 starts from the intersection 13 of the score 2 and a straight line 12 passing through the center of the fixed part 5 and perpendicular to the tearing direction 9.
This is a straight line that is inclined in the tearing direction 9 with respect to the straight line 12 and extends left and right. The other inclined line 11 is the apex 3 of the opening piece 3
This is a straight line that is inclined in a direction opposite to the tearing direction 9 with respect to a straight line 14 that passes through a and is perpendicular to the tearing direction 9, and extends left and right from the apex 3a of the opening piece 30. And these slope lines 1
The angle θ formed between lines 12 and 14 between lines 12 and 14 is 15 degrees. That is, the machined portion 8 according to the present invention is provided in the hatched area surrounded by the slope line 10.11 and the score 2 in FIG.

Regarding the starting point 8a of the machined part 8, as shown in FIG. The distance d to 3a is O≦d≦! maintain a relationship. Preferably, 0≦d≦2/3 Il. here,
The starting point 8a of the machined part 8 does not have to be connected to the score 2. If it is not connected to score 2, the distance a between the starting point 8a of 8 and score 2 is determined by the mechanical part as 1.
It is preferable to keep it to 5 fins or less.

Next, regarding the engraving direction of the machined part 8, either the machined part 8 is carved along the direction perpendicular to the tearing direction 9, or
Alternatively, the angle ψ formed by the engraving direction of the machined portion 8 with respect to the orthogonal direction is set in the range of -15 degrees≦ψ≦+15 degrees. This inclination angle ψ is more preferably -12.5 degrees to +
The range is 12.5 degrees.

FIG. 5 shows the influence of this slope angle ψ on the initial can opening force. As is clear from this figure, the inclination angle ψ is approximately 20
When the angle of inclination is ψ≦±15 degrees, the effect of reducing the initial can opening force appears, and this effect becomes noticeable when the angle of inclination is ψ≦±15 degrees. Further, when the inclination angle ψ is less than ±12.5 degrees, the initial can opening force becomes the smallest. Note that this example uses T with a plate thickness of 0.23111 m.
-4 Make an easy-open can lid using tinplate material, and reduce the remaining thickness of score 2 and the remaining thickness of machined part 8 to 65.
This figure shows the influence of the inclination angle ψ in the case of captivity.

In this way, by defining the starting point 8a and the carving direction of the machined part 8 and carving it near the fixed part 5 of the non-opening side part 6, the tearing direction 9 in the non-opening part 6 near the fixed part 5 can be reduced. The bending rigidity of the can is locally weakened, and as a result, the can opening force is concentrated at the opening starting point, and the initial can opening force is significantly reduced. In other words, the initial can-opening force at the time of initial can-opening decreases,
Can opening properties are extremely good.

FIG. 6 shows several examples of the shape of the machined portion 8 when viewed from above. That is, the machined part 8 is one in which a single thin part having a V-shaped or U-shaped cross section is linearly provided in a direction perpendicular to the tearing direction 9 as shown in FIG.
C) with multiple similar straight thin-walled parts,
As shown in Figure 2(C), the cross-sectional shape is a groove with a wide thin part (see Figure 2(C)), and as shown in Figure 2(d), the starting point 8a of the machined part 8 is scored 2. The starting point 8 of the machined part 8 as shown in FIG.
A is separated from the score 2 and provided discontinuously, a machined part 8 is made into a wide thin part with a groove-shaped cross section as shown in (f) in the same figure, and a A machined portion 8 having a curved shape or the like is adopted.

Furthermore, in the present invention, a plurality of machined parts that reduce the bending rigidity of the opening piece 3 are provided at predetermined intervals on the opening piece 3. FIG. 7 shows several examples of machined parts provided on this opening piece 3. The figure (a) shows a machined part 8 on the opening piece 3. The figure (c) shows the machined part 8. is V-shaped, as shown in the same figure (
C) is an inverted V-shaped machining m8. It has been established that
The figure (6) shows the arc-shaped machined part 8. FIG. 3(e) shows an arc-shaped machined part 81 separated at the center of the opening piece 3. These machined parts 81 may be either continuous lines or broken lines. Further, the machined portion 81 can be formed by any of a score, a thin wall portion, a wavy portion, or a bead. Furthermore, as shown in FIG.
It is also possible to provide the machined portion 81 as a single recess extending over the entire opening piece 3, as shown at 80.

The mutual spacing between the machined parts 81 is preferably 2 to 5I1 m from the viewpoint of reducing the bending rigidity of the opening piece 3. 8. From the front of the machine. When maintaining the mutual spacing within this range, the part of the aperture piece 3 whose bending rigidity is reduced by one machining part 81 becomes continuous with that by the other machining part 81, and the part of the aperture piece 3 whose bending rigidity is reduced by one machining part 81 becomes continuous, and Machining department 8. The tear force under the paper ensures the effect. When this mutual distance exceeds 5, the tearing force varies greatly along the tearing direction 9, making it impossible to tear the opening piece 3 with a stable force. In addition, when the distance between the machined parts 81 is less than 21111, the stiffness of the opening piece 3 becomes unnecessarily weak, and in some cases, the opening piece 3 may be partially torn off.

In addition, a V-shaped or inverted V-shaped machining section 8. When providing a V-shaped side, the angle θ (8th
(see figure) is preferably 45 degrees or less. If this angle θ exceeds 45 degrees, the machined portion 8 causes a decrease in rigidity that makes it easier for the opening piece 3 to bend around the X-x axis.
1 becomes smaller.

By doing so, when opening the can by pulling up the tension tab 4 and tearing the opening piece 3, the initial can-opening force is reduced, and the force required for subsequent tearing is also reduced.

FIG. 9 is a graph showing the transition of the can opening force from the start of opening to the complete opening when the opening piece 3 is removed. In the figure, the solid line A shows the case when the easy-open can lid of the present invention is opened, and the broken line B shows the case when the conventional easy-open can lid is opened. As is clear from this figure, when the present invention is used, both the initial can opening force and the tearing force are reduced, proving that the can can be opened more easily than the conventional can lid.

In addition to reducing the can-opening force and the variation of the can-opening force in this way, the distance a between the apex 3a of the opening piece 3 and the outer periphery of the fixed part 5 (see FIGS. 8 and 10) ) can further reduce the force required to start opening the can.

That is, when the distance a between the apex 3a of the opening piece 3 and the outer periphery of the fixed part 5 is set to 0.4 N or less, preferably 0.3 W or less, the initial can opening force decreases rapidly as shown in FIG. . This is because by reducing the distance a, the influence of the highly rigid fixed portion 5 is transmitted to the apex 3a of the opening piece 3, and the apex 3
This is thought to be due to the fact that the stress concentration at point a becomes more localized.

Next, various easy-open can lids were manufactured from T-4 tin plate with a thickness of 0.23 square meters, and the initial can opening force and tearing force were measured. Table 1 shows the results. In the same table, the conventional easy-open can lid with no machined parts and the easy-open can lid with an auxiliary score 7 on the non-opening side part 6 along the tearing direction 9 as shown in FIG. Can lids (Japanese Patent Publication No. 49-40679) are listed as Comparative Examples 1 and 2, respectively. On the other hand, Examples 1 to 7
is an easy-open can lid having the shape shown in FIG.

No. 1 Table Note: Initial opening force and tear force are given in kgf.

As is clear from Table 1, compared to Comparative Examples 1 and 2, the bending rigidity in the opening piece tearing direction 9 of the non-opening one side portion 6 near the fixed portion 5 is locally weakened by the machining part 8, and the opening In the case of Examples 1 to 7 in which the bending rigidity of piece 3 was weakened,
Initial opening force and tearing force are reduced. Therefore, the easy-open can lid of this example could be opened easily without applying a large force.

The material for the easy-open can lid to which the present invention is applied is not particularly limited, and in addition to the tin and aluminum materials commonly used for can lids, the following materials may also be used.

(1) Non-ferrous metal materials represented by iron and iron alloys or aluminum and aluminum alloys ('2J) Metal materials that have been subjected to surface treatment such as plating or painting to the materials in (1) above (3) (1) and/or or (2) a composite metal material in which an organic material such as a resin is bonded in layers to the metal material (4) a composite metal material in which dissimilar metal materials in (1) and/or (2) are bonded in layers; The present invention is also extremely effective when applied to an easy-open can lid in which a long auxiliary score is carved parallel to the score 2.

〔Effect of the invention〕

As explained above, in the easy-open can lid of the present invention, the rigidity of the non-opening one side portion near the fixed portion of the tension knob in the opening strip tearing direction is locally weakened,
Furthermore, since the opening piece has reduced bending rigidity, both the initial can opening force and the subsequent tearing force are significantly reduced. Therefore, an easy-open can lid with extremely excellent can opening properties is obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating an easy-open can lid according to an embodiment of the present invention, FIG. 2 shows various cross-sectional shapes of machined parts provided on one side of the non-opening part, and FIG. 3 shows the machined parts. Fig. 4 shows the starting point of the machined part, Fig. 5 is a graph showing the influence of the inclination angle of the machined part on the initial can opening force, and Fig. 6 shows the starting point of the machined part. Fig. 7 shows several examples of machined parts provided on the aperture piece, and Fig. 8 shows a V-shaped or inverted V-shaped machined part provided on the aperture piece. Fig. 9 is a graph showing the transition of can opening force from the start of opening to complete opening, and Fig. 10 is a graph showing the angle between the apex of the opening piece and the normal line of the X-x axis. FIG. 11 is a diagram for explaining the distance a between the fixed portion and the outer periphery, and FIG. 11 is a graph showing the relationship between the distance a and the initial can opening force. Moreover, FIG. 12 shows a conventional easy-open can lid in which an auxiliary score is provided on one side of the non-opening portion along the tearing direction. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 -30-17:5-15 -125 0 125 1
5 17.530 ()υ inclination angle φ Fig. 6 (a) (b) (C) (d) (e) (f
) (9) Figure 11 0, + 0.2 0.3 0
．． 4 0.5 interval a (mm) Fig. 12

Claims (1)

[Claims] 1. In an easy-open can lid having an opening piece surrounded by scores and having a tension knob fixed to it, a machined part that locally weakens the rigidity in the tearing direction of the opening piece is installed on the non-opening side near the fixed part. An easy-open can lid with excellent can opening properties, characterized in that the opening piece is provided with one or more machined parts that reduce bending rigidity. 2. The machined part provided on one side of the non-opening part is started from the area from the straight line passing through the center point of the fixed part and perpendicular to the tearing direction of the opening piece to the apex of the opening piece, and in the direction perpendicular to the tearing direction. The easy-open can lid according to claim 1, characterized in that the can lid is opened to extend horizontally in a continuous or discontinuous manner within a range of ±15 degrees. 3. Claims characterized in that the machined portion provided on the non-opening one side portion is a thin wall portion formed by machining the non-opening one side portion into a V-shape, U-shape, or groove shape. The easy-open can lid described in item 1. 4. The machined part provided on the opening piece is a continuous or discontinuous linear, curved, V-shaped or inverted V-shaped score or thin wall along the direction intersecting the tearing direction of the opening piece. 2. The easy-open can lid according to claim 1, characterized in that the lid has a wavy portion, a wavy portion, or a bead. 5. The easy-open can lid according to claim 1, wherein the machined portion provided on the opening piece is a single thin-walled portion or a plurality of depressions. 6. The easy-open can lid according to claim 1, wherein the distance between the apex of the opening piece and the outer periphery of the fixed portion of the tension knob is 0.4 mm or less.