JPS5847520A - Forming method of di can - Google Patents

Abstract

PURPOSE:To form a projecting type stepped shape to a side corresponding to a side wall of a can and a cover of the can, by drawing a bottom part of the can to a projecting type stepped shape so as to be smaller than the inside diameter, and also executing redrawing so that it becomes smaller than said inside diameter. CONSTITUTION:When forming a DI (deep-drawing and squeezing working) can, a bottom part of a drawn can 7 of an inside diameter A is drawn to a projecting type stepped shape so as to be smaller than A, and it is drawn by denoting its inside diameter as B and in the ratio of a range of A/B=1.20-2.61. Also, this drawn can is used, passes through dies of 3a, 3b and 3c in an ironing press, and is squeezed to a can having prescribed side wall thickness. A punch of a diameter ratio B/C=1.00-1.63 of the inside diameter B of the projecting type stepped part and a diameter C of the redrawn part goes forward in the direction of a die 8, a punch 6 is redrawn by the die 8 at the final stroke, and is formed to the projecting type stepped shape.

Description

[Detailed Description of the Invention] The present invention is based on DI (Draw & Ironing:
In other words, it relates to a method for forming cans (deep drawing and ironing).

In conventional DI cans, the side of the can and the bottom of the can were melted with acid at the same time, but the present invention is characterized in that the side wall of the can and the side directly corresponding to the can are formed with a convex step. It is.

A detailed explanation will be given below with reference to the drawings.

FIG. 1 shows a conventional method for forming the bottom of a DI can.

The can 2 that has passed through several stages of dies passes through the final die 3C and is finished into a can with a predetermined side wall thickness. The punch 1 continues to move forward in the direction of the dome-shaped tool 4 until the can bottom 5 is formed into a dome-shaped shape between the dome-shaped tool 4 and the punch 1. After forming the can into a dome shape, the punch 1 moves back in the opposite direction to the direction in which it moved forward, and moves on to the punching process for the next can. The present invention attempts to perform convex stepped molding by utilizing the process of molding the dome shape.

FIG. 2 is a diagram showing details of the convex stepped molding of the DI can of the present invention. The squeeze can 7 is a squeeze can that has been formed with steps in advance in a step before squeezing the DI can. The inside of a squeeze can when used for heather invention.

The ratio of the diameter A and the interior B of the convex stepped section is A/B = 1
．． It is in the range of 20-261. Using this squeeze can, 3a, 3b, 3 in the ironing press
It passes through a die c and is squeezed into a can with a predetermined side wall thickness. Thereafter, the punch with the diameter ratio B/C = 1.00 to 1.63 between the inner diameter 13 of the convex stepped portion and the diameter C of the constricted portion continues to move forward in the direction of the die 8, and on the final stroke, the punch 6 It is drawn again with a die 8 and formed into a shape with convex steps 11. The 0 dimension of the die 8 is a diameter that takes into account ten board thicknesses, ten clearances, etc.

Next, examples will be shown.

Tin plate used for convex stepped molded cans Thickness: 0.3 2 mm Plating amount: 5
6f/Go tempering degree T-1 Tools and can used for drawing and ironing A=67.83 關/B=26n'I C=16m+* A/B X B/C= 4.25 Re-drawing under the above conditions The height of the part with diameter C, h =
A 6 tl, convex stepped 11 DI can was obtained.

FIG. 3 shows the final stroke of the punch, which is redrawn with the die 8, and the bottom of the DI can is formed into a convex stepped shape.

According to the present invention, the convex stepped molding of the bottom of the DI can can be produced by a drawing and ironing process.

Furthermore, at present, the maximum pressure resistance of the bottom of the DI can is 7 to 8, and if the pressure is higher than that, it will buckle and break. If the shape is narrowed down to a convex stepped shape, and the plate thickness is the same as that of a normal dome shape, it is possible to obtain two to three times the pressure resistance. In addition, by forming into a convex stepped shape, it has the advantage of being easier to drink because the mouth is smaller than the easy-open cans, which are the main purpose of DI cans. When carrying around, you don't have to touch the spout much, so it's more hygienic than the current easy-open cans.
. In addition, by forming a convex step, a screw plug can be used by threading the small diameter part, a crown can be used by curling, and a lid can be covered with foil. Additionally, since the pressure resistance is increased, it can also be used in cans that require higher pressure than current applications.

The opposite side of the DI can, which is molded with convex steps, is trimmed and filled with the contents using the normal DI can manufacturing method.
Tighten the side that corresponds to the normal lid part as the bottom part.

It is also possible to draw or redraw the bottom of the squeezed can to form a stepped convex shape, but since the DI can is long, the stroke required for processing is long and productivity is poor.

There is also a method of forming a convex stepped shape with the final diameter at the time of cup forming (before ironing), and then ironing it to make a convex stepped D and I can, and another process after forming the DI can. Immediately after ironing, the first step forming is performed, and in a separate process, drawing is performed again to produce a convex stepped molded can having the ratio of the present invention. There are various methods, materials, and a method of making a convex stepped DI can by one processing step, but these are methods that can be easily inferred from the two inventions.

[Brief explanation of drawings]

The method shown in Figure 1 is currently commonly used. FIG. 2 is a diagram showing a method for forming the bottom of a DI can, and FIG. 2 is an arrangement diagram of punches and dies when forming a stepped convex can bottom according to the first invention. FIG. 3 is a diagram showing the final stroke of the punch when forming a can bottom with a convex step. 1. Normally used ironing punch 2 Normally ironed can 3a, 1st stage die 3b, 2nd stage die 3C0, 3rd stage die, final die for ironing process 4,
Normally used doming punch 5 Normal DI
dome-shaped bottom part 6 of the can; panoch 7 for forming the bottom of the can with convex steps;
Drawn can 8 for forming a can bottom with a convex step Die 9 for forming a can bottom with a convex step A bottom of a draw can that has been previously formed into a convex step to form a can bottom with a convex step 10 Ironing can 11 with a convex stepped molded can bottom;
One can bottom molded with convex steps. Day 1 Figure 2 Figure 3

Claims (1)

[Claims] In a convex stepped molded can in which the bottom of the drawn can of 1 mo A is drawn into a convex stepped shape smaller than A, and the inner diameter is the same, and the inner diameter of the drawn can is C, which is the inner diameter of 14 B, which is further drawn again, By squeezing at a ratio in the range of A/B = 1.20 to 261, and re-drawing at a ratio in the range of B/C = 1.00 to 1.63 in the subsequent ironing process, (Tota + drawing ratio 1 .20 to 4.25) D I is characterized by drawing the bottom of the can into a convex step 1-1 shape and using it as the lid side.
Formation of l fir l13 force method.