JPS6096332A - Drawing die for press machine - Google Patents

Abstract

PURPOSE:To decrease driving power by receiving the descending of an upper die by the hydraulic piston of a lower die blank holder and rising a lower punch piston by the expelling oil thereof thereby decreasing the descending stroke of the upper die by half and increasing the drawing depth. CONSTITUTION:The upper die 5 of an upper die 2 is lowered to lower the hydraulic oil generating piston 14 of a lower die blank holder 12. The expelling oil thereof is fed through a passage 16 to the hydraulic chamber 9 of a freely liftable punch 7 to rise the punch 7. If the total area of the piston 14 is approximately equal to the area of the punch 7 piston, the punch 7 ascends by as much as the descending distance of the upper die 5 by which the descending stroke of the upper die is decreased by half and the initial deep drawing is accomplished. Energy consumption is thus reduced and the working time is shortened.

Description

Detailed Description of the Invention The present invention relates to a drawing die for a press machine. Conventionally, in a drawing die generally used in a press machine, the maximum drawing depth is the same as the drawing depth in a single-shot press. This is V2 of the stroke of the press slide because it requires the height to be pulled out from the mold, and transfer presses also require a stroke for the press slide to move up and down while transporting the molded product pulled out from the mold to the next process. This is 3/8 of the slide stroke. Therefore, the press machine is large in size relative to the drawing depth, requiring a large floor area and a large amount of cost.

The purpose of the present invention is to eliminate these drawbacks and increase the maximum drawing depth without increasing the stroke of the slide by making the punch in the lower mold freely move up and down and pushing it up using the movement of the slide of the press. A press machine that can do the same work with a smaller press, consumes less energy, and saves factory floor space and costs.
The purpose is to provide a model. Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, the structure of the drawing die is shown.

The upper mold (1) is attached to the slide (2) of the press, the lower mold (3) is attached to the press bolster (4), and the right half is with the slide (2) at the bottom dead center (lower limit), and the left half is with the slide (2) at the bottom dead center (lower limit). Half shows a state in which the slide (2) is near the top dead center (ascent limit). The upper die (1) is provided with an upper die (5) having a center hole for drawing, and the knockout (6) is movable up and down in the center hole of the upper die (5), and its lower limit is regulated to fit. However, it is urged downward and is always at the lower limit, with its lower surface coinciding with the lower surface of the upper die (5). The lower die (3) is provided with a punch (7) that faces the upper die (5) and cooperates with it to perform drawing, and the small diameter piston at the bottom of the punch (7) is connected to the lower die set (8). The lower limit is regulated and conforms to the hydraulic chamber (9) so that it can be raised and lowered freely.

Q - An air cylinder 00) is provided on the bottom surface of the lower die set (8) concentrically with the punch (7), and the piston rod of the piston (old version) that fits this moves up and down the bottom plate of the hydraulic chamber (9) in an airtight manner. It freely passes through and is connected to the punch (7). A blank holder (12) is provided on the outer periphery of the punch (7) so as to be able to move up and down and is regulated so that its upper surface coincides with the punch (7) at the upper limit. At a position that receives the lower surface of the blank holder (121), a plurality of hydraulic pressure generation pistons 04, which can be raised and lowered in a hydraulic chamber (I3) provided in the lower die set (8) and whose upper limit is regulated, are provided. . The hydraulic pressure generating piston 04) is urged upward by a spring (151) provided between the lower plate of the hydraulic chamber (13), and its upper surface is brought into contact with the lower surface of the blank holder (12I). Dai 7...) (81 hydraulic chamber (9) and hydraulic chamber (13)
It is communicated with by a passage (16). Punch (7)
) are provided with air holes α powder that open on the top surface and the bottom of the sides to make it easier to pull out the formed product (circle) from the punch (7) after drawing.Hydraulic chamber Q
One of the 31 is provided with an oil supply hole (I91) that opens on the side of the lower die set (8).Air cylinder 0
The cylinder chamber 0) is provided with an air supply hole (20) that opens on the side surface of the lower die set (8). Punch (7)
And the piston circle for generating hydraulic pressure has a hydraulic chamber (9) and (
131 air vent holes (21) and (22) are provided and are normally closed.

Oil is supplied to the oil supply hole (191) through a check valve (2) that closes toward the tank (23).Oil is supplied to the lower part of the tank (23), air is supplied to the upper part, Air supply hole (20
) is supplied with air from the upper part of the tank (23+).Air is supplied to the upper part of the tank (23) at a constant pressure of pK9f/c!L from the compressed air source (2 glazes) via the pressure regulating valve (to). has been done.

Next, we will discuss the effect. Tank (2~ to compressed air source (
C) from the pressure regulating valve (20 constant pressure pKqf/crl
, when 9f/7 air is supplied to about 2, the air supply hole (20
) Air is supplied to the air cylinder 10), and the piston (11) is urged downward to lower the punch (force) to its lower limit.On the other hand, the pressure oil in the tank (231) is supplied to the check valve (24). The oil is filled into the hydraulic chamber (13) through the passage 06), and into the hydraulic chamber (9) through the passage 06).For the first time, the air bleed hole eυ, (221) is opened to bleed the air and then closed.

Here, the pressure receiving surface of the piston part of the punch (7) 2Ao-,
Pressure receiving area of hydraulic pressure generating piston (14) = A1, number =
N.

Pressure receiving area of piston 01) of air cylinder 00) = A2
Then, A2 is made slightly larger than Ao so that the punch (7) can be held at the lower limit. The most commonly used case is Ao = Al x N, that is, the upper die (
5) makes equal the height at which the hydraulic pressure generating piston α is pushed down via the blank holder α and the height at which the punch (7) is pushed up by the generated hydraulic pressure. Ao and A】XN
The relationship between these heights can be changed by changing the area ratio.

6- Also, by setting A, o

In the state shown in the left half of Figure 1, when a blank is fed onto the blank holder 02 and the slide (2) descends, the blank is sandwiched between the blank holder (I2) and the upper die (5) and a creasing force is applied. Punch in state (force and upper die (
5) and the drawing process is performed in cooperation with the above. At this time, the wrinkle pressing force and the squeezing force are equal due to the above-mentioned area relationship.

When the upper die (5) pushes down the hydraulic pressure generating piston 04) via the blank holder (12), the hydraulic pressure chamber (13) is pressed down.
The pressure oil in ) cannot return to the tank (23) due to the action of the check valve (24), so it flows into the hydraulic chamber (9) through the passage (16), causing the piston 01) of the air cylinder 10) to flow. Overcome the downward biasing force and raise the punch (7). Since the upper die (5) and the punch (7) move relative to each other, the lowering height of the upper die (5) is only 1/2 of the drawing depth, and in the case of a single-shot press. The maximum drawing depth can be increased to 2/3 of the stroke of the slide (2), or in the case of a transfer press to 1/2 of the stroke of the slide (2). However, it is assumed that the transfer press is transported at a crank angle of 300° to 60°. At the bottom dead center, the state shown in Figure 1 is reached, and after that, when the slide (2) rises, it descends due to the biasing force of the punch (the force is from the old piston), and the pressure oil in the hydraulic chamber (9) flows into the hydraulic chamber 03). The hydraulic pressure generating piston 04) is raised to the upper limit by the urging force of the pressure oil and the urging force of the spring (15).

At this time, push up the blank holder (12) and molded product 08.
) is removed from the punch (blank holder α2) and the molded product (18) is carried out.

When the oil starts to leak, it is automatically replenished from the tank (23).

As is clear from the above description, according to the present invention, (1)
The maximum drawing depth can be increased. (2) Since the stroke of the slide used for drawing is small and the area near the bottom dead center is used, the energy consumption is reduced to about 1/2 of that of the conventional method. (3) In addition, the timing of transportation can be adjusted to allow for a smaller clamp stroke. (4)
If the drawing depth is the same, it can be processed with a small press, saving floor space and overhead costs. There are great practical effects and benefits such as 0

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of the embodiment and a necessary circuit diagram. 0 1 is an upper mold, 2 is a slide, 3 is a lower mold, 4 is a bolster, 5
is the upper die, 6 is the knockout, 7 is the punch, 8 is the lower die set, 9 is the hydraulic chamber, 10 is the 9-air cylinder, 11 is the piston, 12 is the blank holder, 13 is the hydraulic chamber, 14 is A piston for generating hydraulic pressure, 15 a spring, 16 a passage, 17 an air hole, 18 a molded product,
19 is an oil supply hole, 20 is an air supply hole, 21 is an air vent hole, 22 is an air vent hole, 23 is a tank, 24 is a check valve, 25 is a compressed air source, and 26 is a pressure regulating valve. Patent applicant Representative of AIDA ENGINEERING Co., Ltd.
Meeting 1) Keinosuke 10-

Claims (1)

[Claims] A punch is provided on the lower die facing the upper die so as to be freely raised and lowered, and has a total pressure receiving area that is a certain ratio to the pressure receiving area of the piston portion of the punch, and is placed at a position to receive the blank holder of the lower die. 1. A drawing die for a press machine, comprising: a hydraulic pressure generating piston; and a passage communicating hydraulic chambers in which the hydraulic pressure generating piston and the punch are housed, respectively.