JPS6030545A - Closed forging device - Google Patents

Abstract

PURPOSE:To maintain the specified thickness of a molding by constituting a titled device in such a manner that the pressing force of upper and lower inner punches can be set as desired by relief valves. CONSTITUTION:A thoroughly closed die is formed of a lower die 15, an upper outer punch 6, an upper inner punch 8, a lower outer punch 16 and a lower inner punch 23. The punch 6 and the punch 8 contact with the blank material M in the closed die. When a slide 1 descends, the punch 8 contacts with the material M and receives descending resistance. The punch 8 continues to descend until the punch pressing force set by a relief valve 10 is attained thereby compressing and deforming the material M. A working cylinder 20 extends until the pressure in the liquid chamber in the cylinder 20 attains the punch pressure set with a relief valve 24. The punch 23 is moved upward by the cylinder 20 to compress and deform the material M from below.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a closed forging device for carrying out closed forging. After forming a closed die, the material inside the die is pressure-formed by inserting a punch into the interior of the die.When this closed forging is carried out using a mechanical single-action press, the In order to obtain the double-acting action of closed forging, a double-acting mechanism is incorporated into the mold, etc.

However, in conventional wedge-type double-acting mechanisms and link-type double-acting mechanisms, the size of the closing mold and the entry position of the punch are determined mechanically, which results in uneven product thickness and product accuracy due to the amount of material used. This resulted in problems such as a decrease in the metallurgy and a shortened mold life. In addition, in the conventional spring-type double-acting mechanism in which the lower mold is supported so that it can move up and down with a disc spring within a guide, problems such as wear and seizure between the lower mold and its vertical movement guide tend to occur due to the zero disc spring. As a result, the vertical movement stroke of the lower mold is small, and the push-up load of the lower mold cannot be changed, resulting in problems such as restrictions on the type of steel that can be processed.

(Object of the Invention) The present invention was devised in order to solve the above-mentioned problems of the conventional art. The upper power of the inner punch can be automatically supplied hydraulically by the downward movement of the slide, and variations in material weight can be absorbed by changing the thickness of the hole in the center of the molded product formed by the upper and lower inner punches. The purpose is to provide a closed forging device.

(Structure of the Invention) In the closed forging device of the present invention, an upper die holder body mounted on a slide is provided with an operating cylinder capable of lowering an upper outer punch and an upper inner punch, and each of the operating cylinders is used for setting punch pressure force. A hydraulic circuit equipped with an IJ valve is connected to the lower die holder body mounted on the bed, and an operating cylinder capable of raising the lower inner punch and an upper outer punch capable of being fitted and stopping the lowering of the outer punch are installed. a lower outer punch fitted into the lower mold, and a hydraulic pressure generating device that generates hydraulic pressure by the downward movement of a slide, and the lower inch punch operating cylinder is provided with The device is characterized in that the device is connected to a hydraulic circuit equipped with a relief valve for setting punch pressure force.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

The slide 1 of a mechanical single-acting press has an upper guide holder body 2.
is installed inside the upper die holder main body 2,
two actuating cylinders 5 in which the rams are fitted together so that they can move up and down;
4 is provided. Upper outer ram 5 of operating cylinder 6
An upper outer punch 6 is attached to the lower end of the punch.

An upper inner punch 8 is attached to the lower end of the upper inner ram 7 fitted into the operating cylinder S, and is fitted to the upper outer punch 6 so as to be movable up and down.

The operating cylinders 5 and 4 are provided with hydraulic circuits 11 and 11 respectively equipped with relief valves 9 and 10 for setting the punch pressure force.
12 are connected.

Further, a lower die holder main body 14 is attached to the bed 15 of the mechanical single-action press, and the lower die holder main body 14
A cylindrical lower mold 15 into which the upper outer punch 6 can be inserted and which can stop the upper outer punch 6 is attached to the upper part of the mold.

A lower outer punch 16 is mounted in the lower part of the lower mold 15 so as to be movable upward, and is placed on the bed 15. Inside the lower gooey holder main body 14, there is a discharge cylinder 18 equipped with a non-kout pin 17 that can move the lower outer punch 16 upwardly, and a ram is fitted into the screw □ton 19 of the discharge cylinder 1B and the lower outer punch 16 so as to be able to move vertically. An operating cylinder 20 and a vertical cylinder type hydraulic pressure generator 21 having a ram protruding above the lower guide holder main body 14 are provided.

A lower inner punch 25 is attached to the upper end of the ram 22 of the operating cylinder 20. This operating cylinder 20 includes
A hydraulic circuit 25 provided with the relief valve 24 for setting the punch pressurizing force and the hydraulic pressure generating device 21 are connected.

The same hydraulic pump 26 is used in the hydraulic circuits 11, 12, 25.
Therefore, the insufficient liquid amount is replenished via the check valve 27.

The hydraulic pressure generating device 21 is configured to generate hydraulic pressure by pushing down the ram 29 with the operating rod 2B, which is vertically installed from the upper die holder main body 2, when the slide 1 moves downward.

A hydraulic pump 50 is connected to the discharge cylinder 18 via a pressure reducing valve 51 with relief and an electromagnetic switching valve 52.

(Function) The upper outer punch 6 and the upper inner punch 8 are each placed at the lower limit position by the actuating cylinder 5.4 held in an extended operating state by the hydraulic circuit 11.12. The operating cylinder 20 is simply supplied with a constant amount of liquid by the hydraulic pressure circuit 25 so that the lower inner punch 25 can be moved upward by the supply of liquid by the hydraulic pressure generating device 21 . Therefore, the lower inner punch 25 is also placed at the lower limit position. In this state, when the single acting press is driven and the slide is moved downward, the upper outer punch 6 and the upper inner punch 8 move downward. It is inserted into the mold 15 and stopped when the upper outer punch 6 engages with the inner peripheral portion of the upper end of the lower mold 15. At this time, a complete closed mold is constructed by the lower mold 15, the upper outer punch 6, the upper inner punch 8, the lower outer punch 16, and the lower inner punch 25, and the upper outer punch 6 and the upper The inner punch 8 makes contact.

When the slide 1 further descends, the pressure in the liquid chamber of the operating cylinder 5 that supports the upper outer punch 6 increases, and the pressure exceeding the punch pressure set by the relief valve 9 is released to the outside by the relief valve 9, and the pressure in the liquid chamber of the operating cylinder 5 that supports the upper outer punch 6 increases. 3 is shortened as the slide 1 is lowered. On the other hand, the upper inner punch 8 comes into contact with the material M and receives downward resistance, and the pressure in the liquid chamber of the actuating cylinder 4 that supports the upper inner punch 8 increases until it reaches the punch pressure set by the relief valve 10. In this case, the upper inner punch 8 continues to descend together with the slide 1, compressing and deforming the material M.

At the same time, as the slide 1 descends, the ram 29 of the hydraulic pressure generator 21 is pushed down by the operating rod 28, and the amount of liquid is supplied from the ram 29 into the liquid chamber of the operating cylinder 20. Pressure is IJ IJ-F valve 2
The lower inner punch 23 is moved upward by the operating cylinder 20, and the lower inner punch 23 is moved upward by the operating cylinder 20, and compresses and deforms the material M from below.

Here, if the material M is made to completely fill the sealed interior by the time the slide 1 reaches the dead center, the pressure in the liquid chamber of the actuating cylinder 4 and the pressure in the liquid chamber of the actuating cylinder 20 (
The pressure in the liquid chamber of the liquid pressure generator 21 rises above the punch pressing force set by the relief valve 10.24, and is released to the outside by the relief valve 10.24, so at this time, the upper inner punch 8 and the lower inner punch The movement of 25 stops.

Therefore, closed forging is performed by the closed type configuration operation and the compressive deformation operation of the material M by the upper inner punch 8 and the lower inner punch 25, and if there is variation in the weight (volume) of the material M, the variation will be Upper and lower inner punch 8, 2
It is absorbed by the thickness of the hole in the center of the molded product formed by 5, and does not affect the thickness of the molded product. Although the pressure decreases, the operating cylinders 5, 4, 20 are replenished with the insufficient amount of liquid by the hydraulic pump 26, so the upper outer punch 6 and the upper and lower inner punches 8.25 are returned to their original positions.

On the other hand, when the amount of working fluid is supplied from the hydraulic pump 50 to the discharge cylinder 18 by the electromagnetic switching valve 32, the discharge cylinder 18
lower outer punch 1 via knockout pin 17
6 moves upward in Shimokanazawa 15, the molded product is ejected from the lower mold 15 by this lower outer 1 (inch 16).After the molded product is ejected, the electromagnetic switching valve 52 is switched in the opposite direction. and return the lower outer punch 16 to its original position O The above is one cycle of closed forging. The thickness of the molded product can be set freely, and the thickness of the molded product can be maintained at a constant value since the thickness of the molded product can be adjusted freely by changing the thickness of the hole in the center of the molded product formed by the upper and lower inner punches. No overload is applied to the mold, and the mold can be retained.Since the material is pressure-formed from above and below using upper and lower inner punches, forming is easy.O Closed forging using existing mechanical single-acting presses is easy. possible to 0

[Brief explanation of drawings]

The drawing is a schematic view showing the closed forging device of the present invention in a closed die configuration. 1. Slide, 2. Upper die holder body, 5.4,2
0...Operating cylinder, 5...Upper outer ram, 6...Upper outer punch, 7...Upper inner ram, 8...Upper inner punch, 9, 10.24--Relief valve, 11, 12.2
5... Hydraulic pressure circuit, 15... Bed, 14... Lower die holder body% 15... Lower die plate, 16... Lower outer punch,
17...Knockout pin, 18...Ejection cylinder. 19...Piston, 21...Hydraulic pressure generator, 22.29
...Ram, 25..Lower inner punch, 26.50..Hydraulic pump, 27..Check valve, 2B..Operation rond.
51--Pressure reducing valve, 52--Solenoid switching valve.

Claims (1)

[Claims] The upper die holder body attached to the slide is provided with an actuation cylinder that can lower the upper outer punch and the upper inner punch, and a hydraulic circuit equipped with a relief valve for setting the punch pressure force is connected to each of the actuation cylinders. The lower gouly holder body attached to the upper part includes an operating cylinder capable of raising the lower inner punch, a lower mold into which the upper outer punch can be inserted and which can stop the lowering of the outer punch, and a lower mold inserted into the lower mold. A hydraulic circuit is provided with an outer punch and a hydraulic pressure generating device that generates hydraulic pressure by the downward movement of the slide, and the lower inner punch operating cylinder is provided with the hydraulic pressure generating device and a relief valve for setting punch pressure force. A closed cold forging device characterized by being connected to.