JPS63152540A - Metallic vessel with small double rolled section - 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 (Industrial Application Field) This invention relates to a metal container having a double seam, especially a small double seam.
The present invention relates to a deep drawn can having a heavy seam portion.

(Prior Art) The double seam portion of a conventional metal container has a shape whose cross section is shown in FIG. 1 is a can body, and 2 is a lid.

Conventionally, in order to maintain the rigidity and sealing of the seaming part, the body hook B was 1.90 to 2.10 Bm, and the cover hook C was 1.8 Bm.
0~2.0Oom, seaming height A is 3.00~3.40n
Normally, this is done within a range of about a.

Recently, there has been a severe demand for resource conservation and cost reduction for metal containers, and to achieve this, it is necessary to reduce the amount of metal used to manufacture metal containers. For this purpose, it is necessary to reduce the thickness of the can body, the thickness of H, and the diameter of the blank from which the body hook and can lid are made.

However, there are the following difficulties in meeting these requirements using conventional techniques.

To perform double seaming, flange 3 should be tightened as shown in Figure 2.
The M2 with the curled portion 4 formed thereon is placed on the can body 1 with the curled portion 4 formed thereon, and the curled portion 4 and the flange 3 are deformed by rotating the M2 with the lifter and chuck applying force in the axial direction of the can and pressing the roll 5. I'll let it happen.

The length of the body hook B can be adjusted depending on the magnitude of the pressing force (sealing load) in the direction of the can axis. However, if the seaming is performed with a small seaming load, the body hook B will become shorter, but the shape of the cover hook will not change, the lower clearance D will only increase, and the overlap F will become smaller, resulting in double seaming. The characteristic sealing property is lost.

In order to obtain a sufficient body hook B to ensure an overlap F that does not impair sealing performance, a seaming load above a certain level is required, but the buckling strength in the axial direction of the can body is greater than this seaming load. If it is weaker, the can will not be able to withstand it and will buckle. Therefore, in order to obtain the buckling strength of the can, the wall thickness of the can body and the shape of the can are restricted.

Table 1 shows the occurrence of can body buckling due to changes in body hook length due to changes in seaming load and changes in can body wall thickness.

Table 1 The buckling column shows the number of times buckling occurred when 1000 cans were rolled up in the upper left corner. The * mark on the top row, that is, the wall thickness Q, 1
3 nm and a load of 130 kg indicate a conventional example.

In addition, when tightening, the curled portion 4 of the can lid undergoes diameter reduction processing, but if the thickness of one can lid is reduced, it cannot withstand the lateral stress during diameter reduction, resulting in buckling. As a result, wrinkles occur in the cover hook portion, impairing the sealing performance.

Furthermore, if an attempt is made to reduce the material used by reducing the blank diameter of the lid, the cover hook C will become shorter and the overlap F will become shorter.
becomes small, impairing sealing performance.

(Problems to be Solved) This invention finds the optimal shape of the can body and can lid within the above constraints, and seams them under the most suitable conditions. The objective is to obtain a can body having a seam portion with sufficient overlap using a small body hook and a cover hook.

(Means for solving the problem) As mentioned above, in order to reduce the amount of metal used, the plate thickness of each can body is reduced, and in order to prevent the can body from buckling due to the weight of the one seam part, the seaming load is increased. It is necessary to make it smaller than before. This reduction in the seaming load simultaneously shortens the body hook B and the required flange length K, making it possible to reduce the amount of metal used to manufacture the can body.

Table 2 Table 2 shows the flange length K and seaming load to obtain a reduced body hook. If the flange length becomes too short, the necessary seaming load becomes too large, and the Even at a plate thickness of 0.13mm, buckling of the can body occurs. On the other hand, in order to reduce the seaming load, it is advantageous to have a large flange length K, but as described later, if the flange length is large, the cover hook length C that is commensurate with the reduced body hook can be adjusted. It is no longer possible to use can lids with the reduced blank diameter required to achieve this goal.

In order to obtain a sufficient overlap F with the short body hook B as described above, the blank diameter of the lid is made small and the seaming height A of one seam is made small.

Clearances D and E must be made small to obtain a seamed portion in which cover hook C is small but overlap F is relatively large. If a can lid with the same large blank diameter as before is placed on a can body with a shortened length K of the flange 3 as described above and then tightened, not only will the original objective of reducing costs not be achieved, but the cover hook C is too large compared to body hook B, and the proper 2
This is because a heavily seamed portion cannot be obtained.

Table 3 shows the quality of seaming caused by changes in cover hook C and body hook B.

Table 3 In other words, in the conventional example with the first row cover hook 1.96am and body hook 1.98nn, the overlap F is 0.
．． 76+nm or more, and there was no leakage, but when the body hook was set to 1.68no, the minimum overlap was 0.38+am, and leakage was observed in 21 out of 1000 cans. On the other hand, even in an example in which the body hook is the same as the conventional example and only the cover hook is set to 1.68 mm, the overlap becomes too small and a leak occurs.

According to the purpose of this invention, the body hook B is set at 1°701f.
Table 4 shows the appropriate amount of reduction in the blank diameter of the lid to obtain a proper cover hook C when the cover hook C is shortened to fil.

In other words, when a can lid with the same blank diameter as the conventional one and a reduced amount of 0.5 m is tightened, the overlap F becomes /b even though the cover hook C is large, and leakage occurs.

Needless to say, the reduction in the blank diameter necessary to achieve seaming without leakage naturally results in a reduction in the amount of metal used.

Furthermore, a proper can lid needs to have a reduced blank diameter, as well as an appropriate curl height N and lid outer diameter G.

The fact that the blank diameter is the same and the lid outer diameter G is small means that the outer edge of the lid is largely curled inward, which means that the amount of diameter reduction of the curled portion during seaming can be small. This is advantageous in preventing the occurrence of wrinkles due to buckling of the cover hook portion during diameter reduction processing.

However, if the curl opening diameter J approaches the flange outer diameter H, the tip of the lid will come into contact with the flange when the lid is placed on the can, and in some cases the flange may become deformed, resulting in failure of seaming. occurs. This relationship is shown in Table 5.

In other words, for a can body with a flange length K of 2.55 m, which is the same as the conventional one, if the curl opening J corresponding to a blank reduction amount of 1.0 mm is 64.3 mm or less, seaming failure will occur due to contact with the flange. Flange length K is 2.25mm
Then, no failure due to this contact occurred until the curl opening J reached 63.0 Ilin.

Furthermore, if the above-mentioned accident is to be prevented by increasing the difference between the curl opening diameter J and the flange outer diameter H while keeping the blank diameter constant, the curl thickness N of the lid will inevitably become smaller. If the curl thickness N becomes small, as shown in Fig. 3, when the lids are stacked, the rising portions 6 of the lids will fit tightly together, making it difficult for the seaming device to separate and feed the lids one by one. will occur. In addition, with the can lid with the tab 7, problems such as the tab hitting the inner surface of the upper lid and causing flaws, and insufficient curling making it difficult to tighten the seam properly occur.

Judging from the results in Tables 3 and 5 above, the flange length K is 2.
00 to 2.40 mm and the difference between the mold outer diameter G and the can body inner diameter M is 8.70. It is clear that a combination with a can lid of 1.5 in or less is desirable.

However, in actual production, the difference between the curl opening diameter J and the flange outer diameter H is important as described above, but rather than using this directly as a guideline for control, the difference between the mold outer diameter G
It is convenient to control the diameter by using the 1/2 of the difference between the flange diameter H and the flange outer diameter H.

In that case, the machining distance will be 0.8mm to 1°8m due to the above reasons.
It is desirable that it be within the range of .

Even if the shape of the can body and its corresponding lid are appropriately selected, the shape of the roll used for seaming must be appropriately selected. The seaming is performed by forming the approximate shape of the body hook and cover hook at the 10th rule, and tightening at the 20th rule. However, if the height P of the forming part of the first seaming roll is too large, the seaming height will be too high. As A becomes larger, the overlap F becomes shorter, which not only deteriorates the sealing performance, but also causes poor rolling in of H, causing wrinkles to occur at the tip edge of the curled portion of the lid, and these wrinkles cause flaws on the can body wall. On the other hand, if the height P is small, the end of the can body flange will be obstructed by the lid, and in order to obtain an appropriate body hook, an excessive seaming load will be required, and the thickness of the can body plate will have to be increased.

If the height P of the forming part of the second seaming roll is large, the seaming height A
becomes large, and the overlap F becomes small, making it difficult to maintain sealing performance. Also, if the height P is small, the fourth
As shown in the figure, when the first roll is tightened, a protrusion 8 from the roll occurs at the lower part of the cover hook of the lid, and cracks may also occur in this part.

For the above reasons, if the forming part height P of the first seaming roll and the second seaming roll is appropriately selected, the seaming height A of the can after the first seaming is 2.9011 m or less.

Even if the cover hook and body hook were shortened, a sufficient overlap portion could be secured and sealing performance could be improved.

The body of one can is a flat plate blank rolled up and soldered.

In so-called 3-piece cans that are bonded together, the thickness of the can body doubles at the seam by the amount of overlap, which causes various problems.This invention therefore applies to seamless can bodies such as DI cans and recent deep-drawn cans. It is recommended to do this, and the following tightening examples are all done using DI.
By can.

(Tightening Example 1) As mentioned above, in actual production, it is convenient to control by I, which is 1/2 of the difference between the lid outer diameter G and the flange outer diameter H, so the following experimental example also uses this method. I am by.

Can body inner diameter = 57mm Flange plate thickness = 0.2mwn Substrate thickness = 0.3mm 1st roll height = 2.3mm 2nd roll height = 2.7mm Sealing load = 100kgf The seaming results when varying I under the above conditions are shown below.

The x mark indicating whether seaming was possible or not indicates that the flange portion was pressed and bent by the lid and double seaming could not be achieved. An X mark indicating whether the seaming is good or bad indicates that there is a problem with the sealing performance due to reasons such as the overlap portion F being too short.

As a result, it was found that the thickness is preferably 0.8 to 1.8 mm.

(Tightening Example 2) This shows the case where the forming part P of the first seaming roll is changed, and I
= 1.5 mm, and the other conditions are the same as in Example 1.

In the table, the X mark for can body buckling indicates that there are some products that cannot withstand the seaming load and has buckled. Indicates that some items have defects.

As a result, it can be seen that P in the range of 2.00 to 2.50 mm is a good enemy.

(Tightening example 3) This shows the case where the height P of the forming part of the second seaming roll is changed, I = 1.5 mm, the height of the 10th roll P = 2.4 m, and other conditions are seaming Same as example 1.

Δ and X marks for sealing indicate cracks in the protruding part of the lid,
This indicates that the amount of overlap is insufficient and there is leakage due to double seaming. The X mark on the protrusion of the lid indicates that the protrusion shown in FIG. 4 will occur.

As a result, it was found that the height P is preferably in the range of 2.40 to 2.90 am.

As a result of the above, seaming with a seaming height A of approximately 2.8 to 2.4 mm can be obtained.

(Effects of the Invention) This invention has the above-mentioned configuration.■ By appropriately selecting the shape of the can body and can lid and the shape of the seaming roll, the thickness and diameter of the can body and can lid can be reduced, and the metal Since it is possible to form a double-sealed part with sufficient sealing performance while reducing the amount, it is possible to save resources and reduce costs.

■ By appropriately selecting the shape of can lids, etc., it is possible to prevent can lids from fitting together and scratching the inner surface when lids are stacked.

(1) By selecting the shape of the can body and lid and the shape of the seaming roll, sufficient sealing can be achieved by the reduced double seaming part without any need to change the conventional seaming device.

It is possible to achieve remarkable effects such as:

[Brief explanation of the drawing]

Figure 1 is a partial cross-sectional view of the seaming part of a can, etc., Figure 2 is a partial cross-sectional view of the seaming part before seaming, Figure 3 is a cross-sectional view when the lids are stacked, and Figure 4 shows the protrusion. FIG. 6 is a partial cross-sectional view of the seaming portion when the seaming occurs. 1: Can body 2: Lid 3: Flange 4: Curl portion 5: Sealing roll 7: Tab 8: Extrusion Patent applicant Toyo Seikan Co., Ltd. Applicant agent Patent attorney Fumio Sato (and 2 others) Figure 1 2121 4th ■

Claims (1)

[Claims] 1) A can body without side seams with a flange length K in the range of 2.00 to 2.40 mm, and an outer diameter in which the difference between the inner diameter M of the can body and the can body is 8.70 mm or less. A metal container having a small double-sealed part characterized by double-sealed with a can lid. 2) I, which is 1/2 of the difference between the diameter H of the flange provided at the seamed part of the can body without side seams and the outer diameter G of the can lid, is 0.
A metal container having a small double-sealed portion, characterized in that the seam height obtained by seaming the can body and can lid in the range of 8 to 1.8 mm is as small as 2.90 mm or less. .