JPS5835028A - Method and tool for forming double curled part - Google Patents

Abstract

PURPOSE:To form a double curled part nearly without applying an axial load to a can drum, by carrying out double curling while supporting an annular recessed part formed of the can drum under a cover hook lower end part closely to it by support rolls. CONSTITUTION:An annular recessed part 25 is provided to a can drum 21 which has a flange at an opening part. The bottom part circumferential edge part 29a of an end member having a curl part 27 is formed in a shape to be engaged with the upper part 25b of said annular recessed part 25. Said end member 26 is inserted into an opening end 22, and while said part 25b and bottom part circumferential edge part 29 are clamped by the projecting circumferential surface 30a of the 1st support roll and the engagement part 34b of a chuck 34, preliminary curling is performed by the 1st curling roll 31. Then, while the 2nd support roll 32 engages the annular recessed part 25, a double curled part 37 which completely corvers a cover hook is formed by the 2nd curling roll 33.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and a tool for forming a double seam portion, and more particularly to a method for forming a double seam portion in which almost no axial load is applied to the can body, and a tool used for forming the double seam portion. Regarding tools.

In the conventional double seaming method, as shown in FIG. After placing the curled part 4 of the can body 1 (or the bottom part) and fitting the chamfer 6 into the lid part 3 having the recessed mother tongue part 5, while supporting the lower part of the can body l with a lifter (not shown), As shown in FIG. 1(b), the curled part 4 and flange part 2 are pressed between the first seaming roll 7 and the chamfer 6, so that the end 4a of the curled part is directed upward and downward. A preliminary seaming portion 8 is formed by entering the inner side of the flange portion 2, and then a portion 4a' (corresponding to the curled portion end 4a) is formed by a second seaming roll 9.
The part 2' corresponding to the cover hook (usually called the cover hook) and the flange part 2 (usually called the dehook) are
This is done by forming a double seam 10 in close contact with each other through a sealing gland layer (not shown). In addition, in the double seaming part 10, the panel part 5 of the end member 3
The rising portion 11 from the periphery is usually called a chuck wall. As described above, in the conventional double seaming method, especially in the process of forming the preliminary seaming part 8, the axial component force applied to the flange part 2 is supported to prevent the flange part 2 from escaping and In order to ensure the length of the dehook 2', a fairly large axial load (for example, 9 to 150) is applied to the can body 1, and therefore the conventional double seaming method is applied to the can body made of a material with low axial load resistance. If you try to apply this, the can body will buckle and you will not be able to obtain a satisfactory product. Therefore, the thickness of the can body must be set to a predetermined value (for example, approximately Q, 10 m for steel such as tin-plated steel, 0, 13 m for aluminum alloy, etc., due to constraints from the axial load applied during double seaming).
) (even if it is thinner than the specified value above, problems such as deformation due to external impact will not occur in the case of sealed cans with internal pressure higher than atmospheric pressure), therefore, the thickness of the can body can be reduced. It has been difficult to reduce the thickness and reduce costs. Also, for the same reason, relatively thin plasti 2212
It has been difficult to apply the conventional double seaming method to can bodies made of paper materials or laminates thereof (including laminates with metal foil). Therefore, although the double-sealed part has the advantage of superior reliability in airtightness, the conventional double-sealed method cannot form the part of the can body mentioned above. The problem was that it was difficult.

The present invention aims to solve the problems of the prior art described above.

In order to achieve the above object, the present invention provides a method for forming a double-sealed part by an open end of a can body and an end member, in which a double-sealed part that is opposite to the lower end of the cover hook of the double-sealed part to be formed is provided. An annular recess is formed below the open end portion, and the end member having a bottom peripheral portion having a shape corresponding to the soil surface of the annular recess is inserted into the open end portion to form an annular recess. The upper surface of the recess and the bottom periphery are engaged, and the annular recess and the bottom periphery are held between the support roll that engages the annular recess and the chuck that engages the bottom periphery.
The present invention provides a method for forming a double seam portion that performs double seam fastening.

Furthermore, the present invention provides a tool for forming a double-sealed part by an open end of a can body and an end member, the tool facing the lower end of the cover hook of the double-sealed part to be formed. a support roll that is engageable with an annular recess formed below and close to the open end portion; and a support roll that is retainable to a bottom periphery of the end member having a shape corresponding to the upper surface of the annular recess; The present invention provides a tool for forming a double seam portion, which is characterized by being equipped with a chuck.

The present invention will be described below with reference to drawings showing embodiments.

Reference numeral 21 in FIG. 2 shows an example of a can body to which the present invention is applied, which is formed by drawing and ironing a metal plate blank such as a tin-plated steel plate or an aluminum alloy plate. A flange portion 23 is formed at the edge of the open end portion 22 of the can body 21. The main body portion 24 of the can body 21 is relatively thin (for example, in the case of a tin-plated steel plate, the thickness is 0.10 mm).
w or less, if made of aluminum alloy 0. j3+a
+ or less), if the axial load strength is low, use a flange forming method that applies relatively small axial load, such as the Suginijig method (for example, as disclosed in Japanese Utility Model Publication No. 46-19409). It is desirable to do something. Reference numeral 25 denotes an annular recessed portion having an arcuate cross section extending in the circumferential direction, and is formed by a known method such as a crystallization method or a pulping method using a split mold. The annular recess 25 has an open end portion 22a whose upper end 25a faces the lower end 38a of the cover hook 38 of the double seam portion 37 to be formed (see FIG. 8).
(the distance between the portion 22a and the upper end 25a is the distance between the first seaming roll 31, the lower protrusion 31b and the second seaming roll 31, which will be described later).
It is formed to be slightly larger than the thickness of the lower protrusion 33b of the seaming roll 33, preferably about 0.1 to 1.0 tea), and to be located below it.

The end member 26 (lid) shown in FIG. 3 is for sealing the can body 21 shown in FIG. ), 28 is a wall portion, and 29 is a bottom portion. The peripheral edge 29a of the bottom portion 29 has a shape corresponding to the upper surface 25b of the annular recess 25 (the inner surface between the innermost portion 25e and the upper end 25m of the annular recess 25). That is, the cross section has an arcuate shape concave inward. FIG. 4 shows a state in which the end member 26 is inserted into the can body 21, and in this state, the upper surface 25b of the annular recess 25 and the bottom peripheral edge 2911 of the end member 26 are in almost complete contact, and the flange Part 2
The height of the wall portion 28 is determined such that the tip of the wall portion 3 and the inner surface of the curled portion 27 are almost in contact with each other.

In the present invention, in order to prevent an axial load from being applied to the main body part 24 during double seaming, especially when forming a preliminary seaming part, a support roll that engages with the annular recess 25 of the can body 21 is used. Double seaming is performed while holding the annular recess 25 and the bottom peripheral edge 29a by the chuck that engages with the bottom peripheral edge 29& of the end member 26.

In FIG. 5, which is a schematic plan view of the double seaming tool of the present invention, 30 is a first support roll, 31 is a first seam roll, 32 is a second support roll, 33 is a second seam roll, 34 is a chuck, and 35 is a lifter. The chuck 34 has a peripheral wall portion 34 as shown in FIG.
An engaging part 34b having a shape corresponding to the bottom peripheral edge 29a of the end member is formed below the shaft 34a (the outer diameter is approximately 11 times the inner diameter of the wall 28 of the end member), and is connected to the shaft 34c via the shaft 34c. Although it is rotated by a drive mechanism that does not move, vertical movement is not performed. The first support roll 30 and the second support roll 30
The support roll 32 has protruding circumferential surfaces 30a and 32a of a profile corresponding to the annular recess 25, respectively, and can be approached and approached along the same level with respect to the chuck 34 by a mechanism (not shown, for example a cam mechanism or a linkage mechanism). It is configured so that it can be separated. and chuck 34
As shown in FIGS. 6 and 8, the chuck is arranged so that the engaging portion 34b of the chuck and the circumferential surface 30a are in contact with each other. The shaft 30b of the first support roll and the shaft 32b of the second support roll are rotatably supported by a support (not shown). First seaming roll 31
The second seaming roll 33 has almost the same structure as the conventional seaming roll, and has seaming recesses 31a and 33a, respectively.
It is equipped with Furthermore, during the seaming work, the chuck 34. 1st
The chuck 34. The second four-troll 32 and the second seaming roll 33 are arranged so that their respective axes are located on the same plane. The lifter 35 is rotatably supported coaxially with the chuck 34 on a support (not shown), and is movable up and down by a drive mechanism (not shown).
Double seaming is performed using the above tools as follows. First, the end member 2 is attached to the can body 21 as shown in FIG.
6, place the can body 21 on the lifter 35,
Raise the lifter to remove the retaining portion 34b of the chuck 34.
is engaged with the bottom peripheral edge 29a of the end member. At this time, the first support role 30. Second support roll 32. and the first seaming roll 31. The second seaming roll 33 is located at a distance from the chuck 34. Next, the first support roll 30 and the second support roll 32 (the first support roll 30 may be the only one) are brought close to the chuck 34, and their circumferential surfaces 30a and 32a (the curved surface 301L may be the only one) are engaged with the annular four part 25. let FIG. 6 shows this state.

Next, the roller 34 is rotated (it may be rotated from the front), the first seaming roll 31 is brought close to the curled portion 27, and the curled portion 27 and the flange portion 23 are connected to the roller 34.
4 to form a preliminary seaming part as shown in FIG. The seaming portion 36 shown in FIG. 7 is in a state immediately before the formation of the preliminary seaming portion is completed. As the flange 23 attempts to escape, an axial force acts on the open end 22. However, the annular recess 25 and the bottom peripheral edge 29
Since a is held and pressed by the first support roll 30 and the chuck 34, the above force does not act on the trunk main portion 24. Next, the first seaming roll 31 moves away, the second seaming roll 33 approaches, and with the second support roll 32 engaged with the annular recess 25, double seaming is performed as shown in FIG. A section 37 is formed.

The present invention is not limited to the above embodiments, and the can body 21 may be made of metal plate, plastic, crate 2 paper (including those impregnated with or coated with wax, plastic, or glue),
Or welding opposite ends of a blank made of a laminate made of a suitable combination of glass sheet or film, paper material, and metal foil.

The can body may have two open ends soldered or glued (including heat-sealed) to form a side joint. Among these, the present invention is particularly suitably applied to can bodies made of thin walls with low axial load resistance or materials with poor rigidity. In addition, the material of the end member 26 (lid, bottom) may be a metal plate (including those with a coating film, a printed film, etc. formed on the surface) or metal foil (based on steel or iron to ensure the seaming strength). In the case of foil used as a material, the thickness is approximately 20 μm or more,
A laminate of aluminum foil (preferably about 50 μm or more in thickness) and a plastic film or sheet is selected depending on the purpose of use.

According to the present invention, double seaming is performed while the annular recess of the can body and the bottom periphery of the end member are held and pressed by the support rolls and chucks. Almost no axial load is applied. Therefore, it is possible to double-seal a can body having a thin wall or a body with low rigidity, which was previously impossible, and this has the effect of reducing material costs or expanding the range of material selection.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of the main part for explaining the conventional double seaming method, and Fig. 1 (,) is a drawing showing the state before double seaming, and Fig. 1 (b) is 1(C) is a drawing showing a state in which a double seaming part is formed; FIG. 2 is a longitudinal section of an example of a can body to which the present invention is applied. 3 is a longitudinal sectional view of an example of the end member to which the present invention is applied; FIG. 4 is a longitudinal sectional view showing the end member of FIG. 3 inserted into the can body of FIG. 2; FIG. 5 is a plan view of one embodiment of the tool of the present invention, FIG. 6 is a vertical sectional view of the main part showing the state before forming the preliminary seaming part using the tool shown in FIG. 5, and FIG. Fig. 8 is a longitudinal cross-sectional view taken along the line ■-■ in Fig. 5, showing a state in which the preliminary seaming part is almost formed; It is a longitudinal cross-sectional view showing a formed state. 2°1... Can body, 22... Open end, 25...
Annular recess, 25b...upper surface, 26... end member, 29
...Bottom peripheral portion, 30...First support roll, 3
2...Second support roll, 34...Chaff, Ri,
37...Double winding tightening part, 38...Copperf, 3
8a...Lower end. . Applicant Kishimoto Sho Figure 1 (0) (b) (c) Figure 3 Figure 2 Figure 4 Figure 5 Figure 6 S1 Figure 7

Claims (2)

[Claims] (1) In the method of forming a double-sealed portion by the open end of the can body and the end member, the cover 7 of the double-sealed portion to be formed is placed at the open end portion opposite to the lower end of the cover 7. forming an annular recess below the annular recess, and inserting the end member having a bottom periphery having a shape corresponding to the upper surface of the annular recess into the open end so that the upper surface of the annular recess and the The bottom peripheral edge is engaged, and the annular recess and the bottom Q-ik first are double wound by the satate roll that engages with the annular recess and the chatter that engages with the bottom peripheral edge. A method of forming a double seam part for tightening. (2) A tool for forming a double-sealed part by an open end of a can body and an end member, the tool facing the lower end of the capperf of the double-sealed part to be formed. The I-draw is engageable with an annular recess formed near and below the open end portion thereof, and is engageable with a bottom periphery of the end member having a shape corresponding to the upper surface of the annular recess. A tool for forming a double seam part, characterized by being equipped with a chuck.