JPS582730B2 - Glasses lid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is mainly applied to the current 18L golden cap cans, aluminum end cans, etc., which have a lid with a lid or clinch lid. The present invention provides an improved method for forming the eye metal part of such a can.

The eyelid part of conventional cans of this kind has a single curl, and a wire is wound around the curled part to facilitate processing and at the same time maintain its strength.

However, this method is disadvantageous in terms of economy and productivity because it requires wire and wiring work.

Also, in terms of strength, considering the deformation of the eyelet due to actual clinching with the lid, it is necessary to increase the strength against the tensile stress applied to the eyelet in the horizontal direction. If a wire is used that has not been processed to be completely seamless, the above-mentioned defects may be eliminated, but the strength of this area cannot be expected to increase much, and normal stress (compressive stress) ), even if the increase in strength is quite significant, it would be excessive strength for this type of can, and when considering these things, it is unlikely to be optimal in terms of strength. It is impossible.

As a tentative measure to improve the eye area of this kind of can as described above, we developed a clinching press-lid can with a double curled eye rim and adopted it as a golden cap can for 18L cans. As a result, a method that is rational not only in terms of economy and productivity but also in terms of strength has been developed.

However, in recent years, goal camps have been used repeatedly as two-open cans and three-open cans. It became necessary to further improve the strength of the parts, and in order to meet this need, the triple curl golden cap can of the present invention was developed.

Note that the definition of double and triple curls is that the thickness of the plate near the fitting part with the pusher cover is two or three layers, and therefore, as for the number of turns, one and a half double curls are also included as triple curls. It is something that

The present invention consists of a first step of punching the eyelid material placed on a conveyor or the like and sent intermittently to a burring height sufficient for triple curling, and a vertical compression spring and a radial direction. A second step of punching the first curl by interposing a split die that positively corrects the buckling phenomenon of the curled portion by means of a horizontally acting compression spring; a third step of punching the second curl; The gist of the invention is a method for processing a lid for a push-top can, which comprises a fourth step of punching a third curl, and is characterized by forming a triple curl on the lid.

In the embodiments of the present invention shown in the drawings, those shown in FIGS. 1 to 4 are schematic explanatory diagrams, and 1 is the lid material, 2 is the upright flange portion thereof, 3 is the punch portion, and 4 is the split mold. , 5 is a first curl part, 6 is a second curl part, and 1 is a third curl part.

FIG. 5 is a schematic diagram of the punch in the first step of the present invention, FIG. 6 is a schematic diagram of the punch in the second step (immediately before curl formation), and FIG. 7 is a schematic diagram of the same punch (first curl formation In the figure, 8 is a vertical compression spring, and 9 is a radial compression spring.

In FIG. 1, a hole is first drilled in the center of the flat part where the eyelet lid is to be formed, and then burring is performed to form the rising flange portion 2.

FIG. 2 shows a process of performing single curling, which facilitates curling in the subsequent process.

During molding, since the upright flange portion 2 is long,
Buckling occurs due to forming force, making forming difficult.

Therefore, the split mold 4 is molded after holding the upright flange 17 in a circumferential shape.

In FIG. 3, the single curl is further crushed to form a double curl, and this is because it is difficult to form the final curl shape all at once.

FIG. 4 shows the process of further crushing the double curls to form the final triple curls to complete the product.

In Fig. 5, the upper mold comes down and first forms the eyelet lid, but holes are made in the flat part with the punch cutter 10 and die cutter 11, and then the upper mold comes down and the punch part 3 and the die cutter are formed. -11, the upright flange portion 2 is formed.

In Figure 6, the upper mold comes down and before the first curl punch curls the upright flange, the pressure ring 13
is pushed down toward the housing lock by the vertical compression spring 8, and the housing block 4 is compressed inward by the operation of the pressure ring 13, and the entire outer wall of the upright flange 2 is compressed by the horizontal compression spring. It is held down by the housing block 4 with a force of 9.

In FIG. 7, the upper mold has come down further than in the state shown in FIG. 6, and the compressive force of the vertical compression spring 8 and the horizontal compression spring 9 increases, so that the holding force of the housing block 4 also increases, and the second curl occurs. The punch comes down and the first curl is formed.

Next, to explain the triple processing method of the present invention in detail (see Figs. 8 to 13), assuming that the diameter and curl radius of the eye metal part after molding in the present invention are the same, In the case of triple curling, it is necessary to make the burring height H in the initial molding step larger than that in double curling.

However, considering economic efficiency with a rigid tool, the height H that can be burred in one step is, for thin plates with a thickness of 0.5 or less, when the pilot hole diameter is 2R and the burring diameter is 2R1. , about 10 when H≦CR1-R (C is R/t) 30
), and even if burring is done at the limit height,
It does not become a real triple curl.

Therefore, it can be seen that in order to increase H and to facilitate the first curling in the next step, the burring tool should satisfy the following conditions.

x=(0.18~0.25)ty=(o.t3~0.17)H (However, in one-step purling process) The vertical flange with a large upright amount obtained in this way has a Under conditions where the shape and dimensions are exactly the same as in the case of double or single curls, it is impossible to form triple curls or more using the conventional curl method.

In general, in areas where curling is difficult, such as t/R2) 0.15, the process up to the final curl is performed in several stages to facilitate curling and when relatively precise finished dimensions are required. A splitting method is used, but when there are many double or triple folds, the first curl as a pre-process is equal to the number of turns, and the final curl is R3, which is R2 minus the board thickness. Conventionally, this type of molding could not be used because the degree of processing became more severe and the buckling phenomenon became more pronounced.

In order to solve these problems, we devised a mold that has the function of actively correcting the buckling phenomenon that occurs during curling.

In other words, by applying compressive force horizontally in the radial direction with split molds installed around the entire periphery of the flange, the buckling that occurs and increases as the curl of the flange tip progresses due to the lowering of the upper mold is forcibly suppressed. It was designed to allow curling to be performed.

If the first curl is successfully rolled in in this way, by dividing the processing into several stages, taking into account the degree of processing up to the final curl R2, it is possible to easily create triple or multiple curls using the conventional curl method. Curl formation as described above becomes possible.

17 and 18 are explanatory diagrams of FIG. 14, and are schematic diagrams showing the direction of the load that enlarges and deforms the curled portion in the direction of the arrow.

Thus, according to the present invention, triple curls can be extremely easily formed on the eyelet lid using a relatively simple device, and a truly effective and appropriate processing method can be provided.

[Brief explanation of drawings]

1 to 4 are schematic illustrations of the present invention, FIG. 5 is a schematic diagram of a punch in the first step of the present invention, FIGS. 6 and 7 are schematic diagrams of a punch in the second step, and FIG. Figure to 1st
Figure 3 is a drawing for detailed explanation of the present invention, Figure 14 is a graph of a tensile strength comparison test between the triple curl of the present invention, a conventional double curl, and a jointed wire-containing curl. Figure 15 is a graph of Figure 5. A plan view corresponding to the overall view, FIG. 16 is a sectional view taken along the line AA in FIG. 15, FIG. 17 is an explanatory view related to FIG. Metal lid material, 2 is a rising flange part, 3 is a punch part, 4 is a split mold, 5 is a first curl part, 6 is a second curl part, 7 is a third curl part, 8 is a vertical compression spring, 9 is a radial compression spring;
10 is a punch cutter, 11 is a die cutter, 12 is a first curl punch, and 13 is a pressure ring.

Claims (1)

[Claims] 1. The first step is to punch the eyelid material placed on a conveyor etc. and sent intermittently to a burring height sufficient to perform triple curling, and then press a compression spring in the vertical direction and horizontally in the radial direction. The split mold is compressed inward by the working compression spring, and the entire circumference of the outer wall of the rising flange is pressed by the side wall of the split mold, thereby positively correcting the buckling phenomenon of the curled part. It consists of a second step of punching the first curl using a mold, a third step of punching the second curl, and a fourth step of punching the third curl to form a triple curl on the lid. A method for processing lids for push-top cans.