JPS59174448A - Easy open cover - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an easy-to-open lid that can be opened by tearing an annular score portion defining an openable panel portion using a tab.

Conventionally, there has been known a cap 1 of the type shown in FIG. 1, which is a cap of a relatively small diameter (for example, about 30 wn in diameter), which has a cap body 2 and a tab 3 for sealing a small diameter bottle opening. There is. The cap body 2 is made of a thin metal plate such as an aluminum (alloy) plate, and has a sunken top plate 4.
, a circumferential annular protrusion 5 surrounding the top plate 4, and a skirt portion 6 hanging down from the outer edge 5a of the circumferential annular protrusion 5.

On the outer surface of the top plate 4, an annular score portion 8 defining an open tongue 7 is formed along the inner edge 5b of the peripheral annular protrusion 5.

A rivet portion 9 for fixing the knob tab 3 is formed in the opening/gunnel portion 7 in proximity to the first portion 8a of the score portion 8, which is the initial cutting portion.

(2) The knob tab 3 is equipped with a ring-shaped knob part 3a and a nose part 3b for initially cutting the first part 8a of the score part, and is fixed to the rivet part 9 via the joint nozzle 3C. ing. Since the top plate 4 has a small diameter, the portion 3a1 of the knob 3a facing the nose portion 3b is close to the second portion 8b of the score portion 8 facing the first portion 8a. As shown in FIG. 3(,), the score portion 8 is formed to have a trapezoidal cross section.

The score portion 8 of the conventional high-opening lid 1 of this type was formed to have a substantially equal residual thickness t (FIG. 3(a)) along the entire circumference. In this case, the smaller the remaining thickness, the smaller the force required to open the opening.
(55 μm or less in the case of 7 mm), pinholes are likely to occur in the score portion 8 and the sealing performance is likely to be impaired, and as shown in FIG. This creates a problem in that the score portion 8' is likely to be formed, and the score portion 8 is also likely to be cut during the work of fixing the tab 3.

Further, as shown in FIG. 4, the opening is opened by inserting a finger into the knob 3a, pulling up the knob 3a of the knob tab 3 in the direction of arrow A, and pressing down the nose part 3b. This is done by cutting the vicinity of the first part 8a, then pulling the knob 3a in the direction of arrow B, tearing off the remaining score part 8, and finally separating the second part 8b. If the remaining thickness is uniformly thin, the tearing and separation described above will occur almost simultaneously and instantaneously, and the momentum of that time will make it easy to tear (
Since the second portion 8b of the score portion and the portion 3a1 of the knob portion are close to each other, the following problem occurs.

On the other hand, if the remaining thickness becomes large (for example, 80 μm or more in the case of an original thickness of 0.27 mm), opening becomes difficult, and in extreme cases, opening becomes impossible. Therefore, the range of selection of the remaining thickness is narrow, and if the remaining thickness falls outside of the appropriate range due to work conditions, etc., the above-mentioned troubles are likely to occur.

It is an object of the present invention to solve the problems of the prior art described above.

To achieve the above object, the present invention provides a high-opening lid that is opened by tearing an annular score defining an opening panel with a tab, and a first portion of the annular score defining the opening panel. A fastener for securing the knob tab is formed adjacent to the knob, and the knob tab has a ring-shaped knob portion and a nose portion for initially cutting the first portion of the annular score portion. a portion of the knob facing the nose portion is adjacent to a second portion of the annular score portion opposite to a first portion of the annular score portion; The present invention provides a high-opening lid characterized in that the remaining thickness of the second portion of the score portion is also thicker than the remaining thickness of the first portion.

More preferably, the remaining thickness of the annular score portion is in the following order: a portion near the first portion, a portion intermediate between the portion near the first portion and the portion near the second portion, and a portion near the second portion. , which provides a high-opening lid that becomes thicker in stages.

The present invention will be explained below.

The high opening lid 1 of the present invention is similar to the conventional high opening (5) lid 1 except that the remaining thickness of the score portion 8 varies in the circumferential direction. That is, the first part 8 shown in FIG.
The residual thickness of the portion 10 near a (center angle α) is uniformly the smallest (for example, in the case of an aluminum (alloy) plate with an original thickness of 0.27 mm, material JIS 5000 series, and tempered H19, preferably about 60 μm), and The remaining thickness of the portion 12 (central angle θ) near the portion 8b of 2 is uniformly the largest (preferably about 90 μm in the above case), and the intermediate portion 1 between the portion 10 and the portion 12
1 (center angle β) is uniformly the intermediate thickness between the portions 10 and 12, preferably about 70μ in the above case.
m). The preferable ranges of central angles α, β and θ are 70 to 130 degrees, 65 to 130 degrees, respectively.
and 30 to 100 degrees (however, α+2β+θ=36
0 degrees).

Therefore, the nose portion 3 of the portion 10 near the first portion 8a
The initial cut by b is easily made.

Moreover, there is no risk of pinholes occurring in the score section 8 or formation of defective deformed score sections 8', and there is no risk of the score section 8 being cut during work.

After the tearing starts, the tip of the tearing part reaches the score part (6) until the distance between the opposing parts of 8 reaches the maximum length (
In other words, the position 11a corresponds to α=180 degrees.

11b) requires a relatively large tearing force if the remaining thickness is uniform in the circumferential direction, but in the case of the present invention, the remaining thickness of the intermediate portion 11 including position 118.11b Since it is relatively thin, tearing occurs smoothly with relatively little force.

On the other hand, when the tip of the tearing part passes positions 11a and 11b,
If the residual thickness is uniform in the circumferential direction, the force required for tearing is reduced, but in the case of the present invention, the tearing force is reduced in the vicinity of the second portion 8b.
As the residual thickness of 2 becomes relatively thick, tearing and separation proceed smoothly, and at the final stage of opening, the opening/gunnel part 7 separates from the top plate 4, resulting in injury to hands and fingers. There is no risk of this occurring.

The present invention is not limited to the above embodiments,
For example, the score portion may have a shape other than a circle, such as a teardrop shape. Alternatively, the high-volume lid may be of a type that is joined to the container body through a cap (7) by double seaming.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a high-volume palate (if the remaining thickness of the score part is uniform in the circumferential direction, it is a conventional high-volume palate) which is an embodiment of the present invention, and FIG. 2 is a plan view of ■Longitudinal cross-sectional view along the line, Figure 3 (
a) is a longitudinal sectional view taken along the line ■-■ in Fig. 2, showing the cross-sectional shape of the score part; Fig. 3(b) is a longitudinal sectional view of the main part showing an example of a defective deformed score part; Fig. 4. is a longitudinal sectional view showing the lid in Figure 1 while it is being opened, Figure 5 is a perspective view showing the relationship between the opening/gunnel and fingers after opening, and Figure 6 is the score section of the lid in Figure 1. FIG.

Claims (2)

[Claims] (1) In an allusion palate that is opened by tearing an annular score portion that defines an aperture/gunnel portion according to a knob tab, a portion of the annular score portion adjacent to the first portion of the annular score portion is placed in the opening tongue portion. A fastener is formed for securing the tab, the tab having a ring-shaped tab and a nose for initially cutting the first portion of the annular score. , the portion of the knob facing the nose portion is close to the second portion of the annular score portion opposite to the first portion of the annular score portion; The residual thickness of the part is thicker than the residual thickness of the first part. (2) The residual thickness of the annular score portion is in the vicinity of the first portion,
Claim No. 1: The difference according to claim 1, in which the thickness increases stepwise in the order of the intermediate portion between the vicinity of the first portion and the vicinity of the second portion, and the portion adjacent to the second portion. palate.