JPS5918137B2 - Method for manufacturing outer shell with tension ring for easy-open container lids - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an outer shell for an easy-to-open container lid 5, which is composed of an outer shell having a tension ring and an inner sealing member, and more particularly, to a cylindrical skirt portion with a tension ring integrally formed in the circular panel portion and a pair of lines of weakness extending from opposite ends of the ring toward a free edge of the skirt portion;
The present invention relates to a method of manufacturing an outer shell for an easy-open container lid.

Recently, an outer shell 2 and a shell 1b as shown in FIG. 1a have been used as easy-to-open container lids for containers such as bottles or cans.
A lid composed of an inner sealing member 4 as shown in the figure has been proposed (for example,
(Please refer to the specification and drawings of Publication No. 9, or the specification and drawings of Japanese Utility Model Application No. 53-2766 or 53-2767 filed by the present applicant). The outer shell 2 has a top or circular panel portion 6 and a skirt portion 8 with a tension ring 10 formed in the circular panel portion 6 by stamping and bending.
are integrally formed, and ten pairs of weakened lines 12 for cutting are formed on the skirt portion 8 from both ends (i.e., continuous pieces) of the tension ring 10.
is extending. The inner seal member 4, which has a recess in its center, is fitted into the outer shell 2 and fixed in place by a suitable gasket material.
The inner and outer openings 14 and 16 of the tension ring 10 of the circular panel section 6 are closed. The method for manufacturing the outer shell for the easy-open container lid as described above is to first punch and bend a flat metal material to form the tension ring 10 and its inner and outer openings 14.
and 16, then a pair of weakened lines are formed, and the thus formed metal material is then drawn to form a circular panel portion 6 in which the tension ring 10 is formed.
Attempts have been made to form a shell with a cylindrical skirt 8.

However, in such a conventional manufacturing method, since the openings 14 and 16 are formed prior to the drawing process,
During the drawing process, cracks or cracks may occur near both ends of the outer opening 16 of the tension ring 10, particularly at the weakened line 12, or the shape of the outer arcuate opening 16 of the tension ring 10 may be considerably distorted. It has been found that there are important problems to be solved, such as the appearance of the outer shell being significantly impaired. The present invention has been made in view of the above-mentioned facts.The main purpose of the present invention is to develop a new manufacturing method that can produce a desired outer shell without causing the above-mentioned problems. It is to provide. As a result of extensive research, the inventor of the present invention has discovered the slit forming process necessary to form a tension ring. Prior to the bending process, the metal material is drawn to form a shell having a cylindrical skirt part of a predetermined depth in the circular panel part. Since it is not fully formed, it will weaken even if some force is applied. It has been found that the above-mentioned problem can be skillfully solved without causing any damage to the wire.

That is, according to the present invention, the easy-to-open package has a circular panel portion and a cylindrical skirt portion, a tension ring is integrally formed with the circular panel portion, and a pair of weakened lines extends from both ends of the ring. A method for manufacturing an outer shell for a mold container lid, comprising: (a) at least one set of lance slits having at least two discontinuities located at a predetermined distance in the circumferential direction in a flat metal material; (b) forming a pair of weakened lines extending a predetermined distance from the vicinity of the lance slit toward the center of the disc-shaped portion in the lance slit at a predetermined interval in the circumferential direction; (c) an aperture punching step of punching out an opening of a predetermined size in the disk-shaped portion of the lance slit; and (d) at least the lance slit forming step of (a) above. and a drawing step of drawing the disc-shaped portion in the lance slit to form a shell having a cylindrical skirt portion of a predetermined depth such as a circular panel portion after the weakening line forming step described above; (e) At least after the drawing process of (d) above, the pair of weakening lines is attached to the circular panel portion at a predetermined distance radially outward from the opening from near the inner end of one of the pair of weakening lines. After the slit forming step of forming a slit extending along the opening to near the other inner end of the wire, (f) the opening punching step of above (c), and the slit forming step of above (e), the circular a bending step of forming a tension ring by bending a portion of the panel portion between the opening and the slit;
After the bending step, a shell cutting step of cutting the shell formed in the lance slit from the metal material is provided.

Hereinafter, an embodiment of the manufacturing method of the present invention will be described in detail with reference to FIGS. 2 to 9, which schematically illustrate one embodiment. Second
In the embodiment illustrated in FIGS. 9-9, first a set of internal circular lance slits 22, which are known per se, are formed in an e.g. rectangular metal blank 20 (FIG. 2).

There are at least two inner circular lance slits 22 (two in the illustrated case) located at a predetermined interval in the circumferential direction.
2) discontinuous portions 24. Next, a pair of outer circular lance slits 26 having a diameter somewhat larger than the diameter of the inner circular lance slits 22 is formed concentrically with the inner circular lance slits 2.2 (FIG. 3).

This outer circular lance slit 26 also has at least two (in the illustrated case, two) located at a predetermined interval in the circumferential direction.
2) discontinuous portions 28. Each of the discontinuities 28 of the outer circular lance slit 26 is located circumferentially intermediate the discontinuities 24 of the inner circular lance slit 22, so that in the case shown, the discontinuities 28 of the inner circular lance slit 22 24 and the discontinuity 2 of the outer circular lance slit 26
8 are alternately located at 90 degree intervals. The lance slits 22 and 26 as described above prevent the peripheral edge 32 of the metal material 20 from deforming due to the drawing process when the disc-shaped portion 30 inside the inner circular lance slit 22 is later drawn. (Generally, when performing the manufacturing process automatically and continuously, the metal material 20 is processed using the peripheral edge 32 of the metal material 20 or one or more guide holes formed therein. When the peripheral edge 32 of the metal material 20 is deformed, it becomes impossible to accurately perform the feeding and positioning of the metal material 20), and also the disk of the metal material 20. This is necessary in order to accurately perform the drawing process itself of the shaped portion 30.

In the illustrated case, two sets of circular lance slits 22 and 26 are formed on the inner and outer sides, but for example, the metal material 2
What is the drawing depth of the drawing process for the disc-shaped part 30 of 0? If the diameter is relatively shallow, the desired purpose can be achieved by forming only one set of circular lance slits. If the lance slits are relatively deep, three or more sets of concentric circular lance slits may be formed as necessary. Furthermore, although each set of lance slits is shown as having a generally circular shape, the lance slits may be of a spiral shape or the like as is well known to those skilled in the art. Following the above lance slit forming step (FIGS. 2 and 3), in the illustrated embodiment, a circular opening 34 is punched in the center of the disc-shaped portion 30 of the metal material 20 (opening punching). process) and form a pair of weakened lines 36 (weakened line forming process) (Fig. 4)
. Circular aperture 34 forms an aperture located inside a later formed tension ring, and a pair of lines of weakness 36 constitute lines of weakness for cutting the shell. A pair of weakening lines 36 are formed at intervals in the circumferential direction and extend a predetermined distance from the vicinity of the inner circular lance slit 22 toward the center of the disc-shaped portion 30. The so-called score or metal material 3 cut across only a part of the
In addition, in the illustrated embodiment, a linear weakening line 36 is formed, but the form of the weakening line is not limited to this. For example, a curved line of weakening can be formed, or the shape of a pair of weakening lines can be made to be different from each other.
Following the above-described opening punching step and weakening line forming step (FIG. 4), the disk-shaped portion 30 of the metal material 20 is drawn to form a circular panel portion 38 and a cylindrical skirt portion 4 of a predetermined depth.
0 (drawing step, FIG. 5). During this drawing process, the disk-shaped portion 30 of the metal material 20
is formed into a shell as described above, and due to the influence of the drawing process, the annular portions 42a, 4 between the inner circular lance slit 22 and the outer circular lance slit 26 are formed into a shell as described above.
2b, 42c and 42d are considerably modified, as can be readily seen from FIGS. 4 and 5. However, since the annular portions 42a, 42b, 42c, and 42d are easily deformed, the peripheral edge 32 of the metal material 20 is substantially prevented from being deformed due to the drawing process.
And is Ciel drawn accurately to the desired shape? guaranteed. After the above-mentioned drawing process (Fig. 5), an arcuate slit 44 is formed at a predetermined distance in the radial direction from the circular opening 34 formed by the above-mentioned aperture punching process (Fig. 4). Forming step, 6th
figure).

In the illustrated embodiment, the slit 44 extends from the vicinity of one inner end of the pair of weakened lines 36 to the pair of weakened lines 36.
The opening has an arcuate shape that extends along the circular opening 34 to near the other inner end of the opening 6 and has a predetermined width. Following such a slit forming step (FIG. 6), the arc-shaped portion 46 remaining between the circular opening 34 and the slit 44 having an arc-shaped opening shape is shaped into a substantially U-shape (U-shape). (Fig. 7) so that both legs of the U-shaped portion extend toward the inside of the shell, that is, upward in FIG. (Figure 8)
In this way, a tension ring 48 having a substantially hollow circular or elliptical cross section and an arcuate or circular shape as a whole is formed (bending step).

After this bending step (FIGS. 7 and 8), the shell is separated from the metal material 20, for example at the edge of the cylindrical skirt portion 40 of the shell (separation step, FIG. 9).

In this way, the outer shell of the easy-open container lid as shown in the lower part of FIG. 9 is molded. The outer shell as shown in the lower part of FIG. 9 may, if desired, be further curled at the free edge of the cylindrical skirt portion 40 to form the outer shell as shown in FIG. 1a. You can also do that.

Further, such curling processing may be performed simultaneously with the above-described cutting process, and a curl may be formed on the free end edge of the cylindrical skirt portion 40 at the same time as the shell is cut from the metal material 20. 10 to 12 are FIG. 6 (slit forming process), FIG. 7, and FIG. 8 (bending process) in the embodiment as described with reference to FIGS. 2 to 9.
A modification of the process illustrated in FIG.

In the slit forming step shown in FIG. 10, which is performed subsequent to the drawing step (FIG. 5), an aperture punching step (
An arcuate slit 44 formed at a predetermined distance in the radial direction from the circular opening 34 formed by the method shown in FIG. It is formed by a notch in the form of a cutting line extending along the circular opening 34 to near the other inner end. As clearly shown in FIG. 10, both ends of such a slit 44 include a portion 44a extending perpendicularly to the arc-shaped portion, and a portion 44b further extending in an arc-shape from both ends of this portion 44a. It has In the bending step shown in FIG. 11, which follows the slit forming step of forming the slit 44 in the form shown in FIG. In addition to being bent into a generally U-shape (so that the opposite legs of the U extend toward the inside of the shell, i.e. upwardly in FIG. 11), the slit 44 is defined by portions 44a and 44b. The portion 50 is bent substantially perpendicularly to the inside of the shell, and the portion 52, which has the slit 44 as the inner free edge and extends along the slit 44 at a predetermined width, is bent substantially perpendicularly to the inside of the shell.

Thereafter, the circular opening 34 is opened as shown in FIG.
and the slit 44, bending both legs of the substantially U-shaped portion in a direction toward each other, thus forming an arcuate tension ring 48 having a substantially hollow circular or elliptical cross section;
The generally perpendicularly bent portions 50 and 52 on the inside of the shell are bent to curve them toward the circular panel portion 30 of the shell. After the bending process as described above (FIGS. 11 and 12), the cutting process as already explained with reference to FIG. 9 is performed. This shows an embodiment in which slight modifications have been made to the modification shown in FIGS.
In the slit forming step shown in FIG. 13, which is carried out by drawing the drawing step (FIG. 5), the opening punching step (
An arcuate slit 44 formed at a predetermined distance in the radial direction from the circular opening 34 formed by the method shown in FIG. However, both ends of the slit 44 shown in FIG. 13 are curved radially inward at a relatively small curvature, and are smoothly connected to each of the pair of weakened lines 36.

The bending process shown in FIGS. 14 and 15 following the slit forming process of forming the slit 44 in the form shown in FIG. 13 is substantially the same as the bending process shown in FIGS. 11 and 12. It is.

That is, in the bending process shown in FIG. 14, the arc-shaped portion 46 between the circular opening 34 and the slit 44 is
A portion that is bent into a U-shape (so that both legs of the U-shape extend to the inside of the shell, that is, to Hijikata in FIG. 14), has the slit 44 as the inner free edge, and extends along the slit 44 with a predetermined width. 52 at a substantially right angle to the inside of the shell. Thereafter, the circular opening 3 is opened as shown in FIG.
4 and the slit 44 are bent in the direction toward each other, thereby forming an arc-shaped tension ring 48 having a substantially hollow circular or elliptical cross section, and forming an arcuate tension ring 48 on the inside of the shell. The approximately right-angled portion 52 is bent to curve it toward the circular panel portion 30 of the shell. After the bending process as described above (FIGS. 14 and 15), the cutting process is performed as already explained with reference to FIG. Above, Figures 2 to 1
Although three embodiments of the manufacturing method of the present invention have been described in detail with reference to FIG. Modifications can be made.

For example, in the illustrated embodiment, the aperture punching step (
(Fig. 4) is performed at the same time as the weakening line forming process (Fig. 4) and before the drawing process (Fig. 5), but the aperture punching process (Fig. 4) is performed in the drawing process (Fig. 5). It may be performed after the slit forming step (FIG. 6), prior to, simultaneously with, or following the slit forming step (FIG. 6).

Furthermore, the aperture punching step (FIG. 4) is performed before the drawing step (FIG. 5), prior to the lance slit forming step (FIGS. 2 and 3) and the weakening line forming step (FIG. 4). The aperture punching step (FIG. 4), which may be performed after the step (FIG. 4), can be performed at any time before the bending step (FIG. 7). Further, in the illustrated embodiment, the lance slit forming step (FIGS. 2 and 3) is first performed, and then the weakening line forming step (FIG. 4) is performed, but the lance slit forming step ( The drawing process (Figures 2 and 3) and the weakening line forming process (Figure 4) are different from each other.
As long as it is before (Fig. 5), it can be performed in the reverse order or at the same time.

Additionally, in the illustrated embodiment, the circular aperture 34 and the arcuate slit 44 form a generally arcuate to circular tension ring 48; however, if desired. The shapes of the openings and slits can be appropriately selected so as to form a tensile ring having any shape as a whole, such as an elliptical shape, a rectangular shape, a hexagonal ring, or the like.

Additionally, in the illustrated embodiment, a tension ring 48 is formed at the center of the circular panel portion 38 of the outer shell; 48 can also be formed at the periphery of the circular panel section 38 rather than at its center (ie, eccentrically relative to the center of the circular panel section 38). Furthermore, while the illustrated embodiment utilizes a square metal stock 20 of suitable dimensions for manufacturing a single outer shell, it is possible to perform the outer shell manufacturing process as rapidly and continuously as desired. In order to accomplish this, a continuous strip of metal material unwound from a strip of metal material or a coil of metal material having a predetermined length is progressively fed into each step, and a number of outer shells are formed from such strip of metal material. It is also possible to manufacture them sequentially.

In addition, when using a band-shaped metal material, the width direction dimension of the band-shaped metal material should be suitable for manufacturing two or more outer shells, and the band-shaped metal material should have two or more rows of outer shells. It is also possible to perform each step sequentially (a staggered arrangement is also possible).

[Brief explanation of the drawing]

FIG. 1a and FIG. 1b are sloped surfaces showing the outer shell and inner seal portion of the easy-open container lid, respectively. Figures 2 to 9
The figure is a perspective view schematically showing each step of an embodiment of the manufacturing method of the present invention. Figures 10 to 12 and Figures 13 to 15 are
A slope diagram schematically showing a modification of some of the steps of the embodiment shown in FIGS. 2 to 9? 20... Flat metal material, 22 and 26... Lance slit, 24 and 28... Discontinuous portion, 34... Opening, 3
6...Weakening line, 38...Circular panel part, 40...Cylindrical skirt part, 44...
・Slit, 48...Tension ring.

Claims (1)

[Claims] 1. An easy-to-open type that has a circular panel portion and a cylindrical skirt portion, a tension ring is integrally formed in the circular panel portion, and a pair of weakened lines extends from both ends of the ring. A method of manufacturing an outer shell for a container lid, comprising: (a) at least one set of lance slits having at least two discontinuities located at a predetermined distance in a circumferential direction in a flat metal material; a lance slit forming step to form a lance slit;
(b) Forming weakened lines by forming a pair of weakened lines extending a predetermined distance from the vicinity of the lance slit toward the center of the disc-shaped portion within the lance slit at a predetermined interval in the circumferential direction. (c) an aperture punching step of punching out an opening of a predetermined size in the disc-shaped portion within the lance slit;
(d) At least after the lance slit forming step in (a) above and the weakening line forming step in (b) above, the disc-shaped portion in the lance slit is drawn to a predetermined depth with the circular panel portion. (e) At least after the drawing step of (d) above, a drawing step of forming a shell having a cylindrical skirt portion; a slit forming step of forming a slit extending along the opening from near the inner end of one of the pair of weakening lines to near the other inner end of the pair of weakening lines;
f) After the opening punching step of above (c) and the slit forming step of above (e), bending to form a tension ring by bending the portion of the circular panel portion between the opening and the slit. and (g) a shell cutting step of cutting the shell formed in the lance slit from the metal material after the bending step of (f) above. 2. The method according to claim 1, wherein in the slit forming step (e), the slit is formed by punching an opening having a predetermined width. 3. In the slit forming step in (E) above, the slit is formed by cutting in the form of a cutting line, and in the bending step in (F) above, the slit in the circular panel portion is 2. A method as claimed in claim 1, in which a free edge and a predetermined width extending along the slit are bent inside the shell.