JPH07115100B2 - Manufacturing method of press fit flange for drum can - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a drum can press-fitting flange arranged in a drum can.

[Conventional technology]

Conventionally, a press fit flange for a drum can placed on a drum can is formed by drawing a plate material into a container with a flange as shown in FIG. 5 (a), and then as shown in FIG. Punching is performed, and thereafter, as shown in (c), the tubular portion of the container is formed by molding, and as shown in (d), the flange portion of the container is trimmed into an octagonal shape. Has been done.

The press-fitted flange for the drum can thus pressed is, as shown in FIG. 6, an end portion on the bottom side of the tubular portion 11.
After cutting 13 by cutting, the inner diameter portion 15 on the bottom side is cut to a predetermined size, and finally screwed to manufacture.

[Problems to be Solved by the Invention]

However, in such a conventional manufacturing method, after pressing, it is necessary to cut the bottom end 13 of the tubular portion 11 by cutting, and also to cut the bottom inner diameter portion 15 to a predetermined size. However, there is a problem in that a cutting machine such as a lathe is required, and the loss of material increases, which increases the manufacturing cost.

Therefore, it is conceivable to form the inner diameter portion 15 on the bottom side of the tubular portion 11 into a predetermined dimension by a general ironing process. In this case, the wall thickness reduction rate of the tubular portion 11 is 35 to 50. Since it exceeds the range of%, the following problems occur.

That is, in general, the surface angle of the bottom side end surface of the tubular portion 11 is 15
If the ironing is performed within the range of degrees, buckling occurs in the tubular portion 11 to deteriorate the quality, and as the surface angle approaches 0 degrees, the buckling phenomenon becomes remarkable and the machining becomes impossible. It is necessary to perform the ironing process in a plurality of times within a range where buckling does not occur, and in this case, there is a problem that the material needs to be annealed or lubricated such as a bonder.

The present invention has solved the above problems, and the inner diameter of the bottom portion of the tubular portion of the drum can press-fitting flange has a predetermined dimension by a single ironing process without causing buckling in the tubular portion. It is an object of the present invention to provide a method for manufacturing a press fit flange for a drum can that can be molded into a cylinder.

[Means for Solving the Problems]

The method for manufacturing the drum can press-fitting flange according to the present invention, the plate material is drawn into a flanged container shape, the bottom part of the container is punched, and then the cylindrical part of the container is formed by molding, and further In a method for manufacturing a drum can press-fitting flange for trimming a flange portion of a container, at the time of forming the tubular portion, at the bottom opening end surface of the tubular portion, the inner diameter side is angled from 15 degrees to 60 degrees toward the flange side. A material side taper surface that is inclined by is formed in advance, and then, in the tubular portion, from the material side taper surface side, toward the position facing the material side taper surface in the same direction as the material side taper surface. A punch having a taper surface on the punch side that is inclined at an angle of 15 to 60 degrees is inserted, and the bottom side of the tubular portion is ironed.

[Action]

In the method for manufacturing the drum can press-fitting flange of the present invention, at the time of forming the tubular portion, the bottom side opening end surface of the tubular portion, the material side of which the inner diameter side is inclined at an angle of 15 to 60 degrees toward the flange portion side. A taper surface is formed in advance, and then, from the material side taper surface side, at a position facing the material side taper surface, in the same direction as the material side taper surface, at an angle of 15 to 60 degrees. A punch having an inclined punch side taper surface is inserted, and the bottom side of the tubular portion is ironed.

〔Example〕

 Hereinafter, details of the method of the present invention will be described with reference to the drawings.

In the method for manufacturing the press fit flange for the drum can according to the present invention,
Almost the same as already described using the figure, after drawing the plate material into a container with a flange, punching the bottom of the container,
After that, the tubular portion of the container is raised by molding, and the flange portion of the container is trimmed to press the drum can press-fitting flange.

Thus, in the method for manufacturing the drum can press-fitting flange of the present invention, as shown on the right side of FIG. 1, when the tubular portion 21 is formed, the bottom opening end face of the tubular portion 21 has an inner diameter side flange portion.
A material side taper surface 25 that is inclined at an angle of 15 to 60 degrees toward the 23 side is formed in advance. The left side of FIG. 1 shows a conventional tubular portion, which is longer than the tubular portion 21 of the present invention by a length l.

After that, as shown in FIG. 2, the cylindrical portion 21 is moved from the material-side tapered surface 25 side to a position facing the material-side tapered surface 25 in the same direction as the material-side tapered surface 25. From degree
A punch 29 having a punch-side tapered surface 27 inclined at an angle of 60 degrees is inserted, and as shown on the right side of FIG.
The inner diameter portion 31 on the bottom side is ironed and molded into a predetermined size.

FIG. 4 shows an example of a die structure for ironing the inner diameter portion 31 on the bottom side of the tubular portion 21, and the right side of the figure shows the state when the upper die is in contact with the material. Indicates the state at the end of ironing.

In the figure, reference numeral 33 indicates an upper die set fixed to the lower surface of the slide, and the die 35 is fixed to the lower surface of the upper die set 33.

On the other hand, in the figure, reference numeral 37 indicates a lower die set fixed to the upper surface of the bolster.
A punch 29 is fixed to the upper surface of 37.

A lifter 39 is arranged surrounding the punch 29. The lifter 39 is biased upward by a cushion pin 41, and the lower end of the cushion pin 41 is in contact with the upper surface of the cushion pad 43.

Further, a lifter guide stopper 45 for preventing the lifter 39 from moving upward is arranged outside the lifter 39, and the lifter guide stopper 45 is fixed to the upper surface of the lower die set 37.

Further, a lift pin 47 is arranged by inserting the lower die set 37 and the lifter 39, and the upper end of the lift pin 47 is in contact with the flange portion 23 of the material 51.

The lift pin 47 is biased upward by a spring 53, and the lower end of the lift pin 47 has a cushion pad 43.
Is in contact with the upper surface of.

In the die for ironing configured as described above, the material 51 is moved downward against the lift pins 47 by the downward movement of the slide, and is formed on the bottom opening end surface of the tubular portion 21 of the material 51. The material-side taper surface 25 abutted on the punch-side taper surface 27 formed on the punch 29, and further by moving the material 21 downward, the inner diameter of the tubular portion 21 is ironed.

Thus, in the method for manufacturing the drum can press-fit flange of the present invention, at the time of forming the tubular portion 21, the bottom opening end surface of the tubular portion 21, the inner diameter side is 15 degrees to 60 degrees toward the flange portion 23 side. A material-side taper surface 25 that is inclined at an angle α is formed in advance, and then the material-side taper surface 25 is formed on the tubular portion 21 from the material-side taper surface 25 side to a position facing the material-side taper surface 25.
Insert a punch 29 having a punch side taper surface 27 inclined at an angle β of 15 ° to 60 ° in the same direction as the cylindrical portion 21
Since the bottom side is ironed, the inner diameter of the bottom side of the cylindrical part 21 of the press fit flange for drum can is formed into a predetermined size by one ironing without buckling the cylindrical part 21. It becomes possible to do.

As a result, it is not necessary to cut the inner diameter of the tubular portion to a predetermined size as in the conventional case, a cutting machine such as a lathe is not required, and material loss can be reduced.

Then, according to the method of the present invention, without buckling the tubular portion 21, the wall thickness reduction rate over a wide range up to about 70%,
It becomes possible to perform ironing.

In the method of the present invention, the angle α of the material-side tapered surface 25
The angle of 15 to 60 degrees is limited to the taper surface on the material side.
This is because if the angle of 25 is smaller than 15 degrees, buckling of the material 51 is likely to occur, and if it is larger than 60 degrees, ironing becomes difficult.

Similarly, the angle of the punch side taper surface 27 is limited to an angle of 15 degrees to 60 degrees, because if the angle of the punch side taper surface 27 is smaller than 15 degrees, the material 51 may buckle. This is because ironing becomes difficult when the angle becomes larger than 60 degrees.

In the method of the present invention, it is needless to say that the angle α of the material side taper surface 25 and the angle β of the punch side taper surface 27 do not necessarily have to be the same.

(Effects of the Invention) As described above, in the method for manufacturing the drum can press-fitting flange of the present invention, at the time of forming the tubular portion, the bottom opening end face of the tubular portion, the inner diameter side is 15 degrees toward the flange portion side. The material side taper surface that inclines at an angle of 60 degrees is formed in advance, and then the same as the material side taper surface from the material side taper surface side to the position facing the material side taper surface on the tubular part. Since the punch with the punch side taper surface that is inclined at an angle of 15 to 60 degrees in the direction is inserted and the bottom side of the cylindrical part is ironed, the bottom part of the cylindrical part of the drum can press-fit flange is There is an advantage that the side inner diameter can be formed into a predetermined size by a single ironing process without causing buckling of the tubular portion.

[Brief description of drawings]

FIG. 1 shows a material formed by molding, the right side of the figure shows the case of the method of the present invention, and the left side of the figure shows the conventional case. FIG. 2 is an explanatory view showing a state in which a punch is inserted into the material shown in FIG. FIG. 3 is an explanatory view showing a material ironed by the method of the present invention. FIG. 4 is a vertical sectional view showing a die structure for ironing. FIG. 5 is an explanatory view showing a conventional method for manufacturing a press fit flange for a drum can. FIG. 6 is an explanatory view showing cutting of the end face and the inner diameter of the tubular portion. [Explanation of symbols for main parts] 21 …… Cylindrical part 23 …… Flange part 25 …… Material side taper surface 27 …… Punch side taper surface 29 …… Punch.

Claims (1)

[Claims] 1. A drum can for drawing a plate material into a container with a flange, punching out the bottom of the container, then starting up the cylindrical portion of the container by molding, and further trimming the flange of the container. In the method for manufacturing a press-fitting flange for molding, at the time of forming the cylindrical portion, a material-side tapered surface in which the inner diameter side is inclined at an angle of 15 to 60 degrees toward the flange portion side is formed in advance on the bottom opening end surface of the cylindrical portion. After that, the material is tapered from the side of the material side taper surface to the tubular part at a position facing the material side taper surface in the same direction as the material side taper surface at an angle of 15 to 60 degrees. A method for manufacturing a press-fitting flange for a drum can, which comprises inserting a punch having a punch-side taper surface and ironing the bottom side of the tubular portion.