JPH0478379B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is used for closed forging in which a material is sealed in the space between an upper mold and a lower mold, and a punch is inserted into the space to form the material. This relates to a mechanical hydraulic double-acting press.

[Prior Art] Double acting presses for performing this type of closed forging include hydraulic presses and mechanical presses.

In the case of hydraulic presses, there are two methods: one that relies on the hydraulic pressure of a hydraulic pump for working energy, and the other that temporarily stores potential energy in an accumulator and releases it all at once during work.

However, in the former method, there is a practical limit to the capacity of the pump, making it difficult to increase the speed and forcing an unrealistic waste of a large amount of energy.
The noise of the oil passing through the valve and the noise of the hydraulic pump are louder than the noise of a mechanical press (which has the same capacity as a hydraulic press).

Furthermore, the latter method requires a complex control system, and in addition, synchronization of the die and punch is impossible if the double-acting press is at high speed.

Next, in the case of a mechanical press, work energy is stored in the form of flywheel rotational energy, which is extracted at any time by a clutch and brake and used for work. Such a mechanical press has high speed and excellent controllability.

However, when configuring a double-acting press, the structure becomes complicated, and it is difficult to combine the presses into a realistic size, especially when the pressing force is high relative to the size, such as a forging press.

Furthermore, mechanical presses require a complicated mechanism for die height adjustment and do not have an effective means for releasing the stakes.

[Purpose of the invention] This invention was proposed in view of the above-mentioned circumstances, and its purpose is to combine the advantages of hydraulic presses and mechanical presses, such as high speed and no need for slide adjustment (die height adjustment), and to To provide a mechanical-hydraulic double-action press for double-action forging, in which a forging material can be easily moved in and out between dies, and the driving force of an inner punch to the material can be freely selected.

[Structure of the Invention] A mechanical-hydraulic double-action press according to the present invention includes an upper slide that moves forward and backward by mechanical means, an upper mold attached to the upper slide, and a lower part of a frame opposite to the upper slide. a lower slide fitted into the cylinder;
pressure adjusting means for maintaining the closing pressure of the upper and lower molds in order to retract the lower slide in response to the movement of the upper slide; a lower mold attached to the lower slide; an inner ram that penetrates the lower mold and the lower slide and is fitted into the cylinder; a fluid blocking means that blocks the flow of fluid from the cylinder; It is equipped with a hydraulic drive source that generates hydraulic pressure to move the ram, lower slide, and lower mold upward.

[Example] The present invention will be described below based on an illustrative example.

As shown in FIGS. 1 to 4, an upper slide 3 that moves up and down by mechanical means 2 is provided at the top of the frame 1, and a lower slide 4 that moves up and down by hydraulic pressure is provided at the bottom of the frame 1. It is being

Mechanical means 2 is a normal drive mechanism (not shown)
a gear 5 driven by a gear 5, a crankshaft 6 having a cam 6A and rotatably attached to the frame 1, and an eccentric body eccentrically and rotatably attached to the cam 6A and rotatably attached to the upper slide 3. 7, the crankshaft 6
The rotation of the eccentric body 7 caused by the rotation of the upper slide 3 causes the upper slide 3 to move up and down with a predetermined stroke along a suitable guide (not shown).

An upper mold 10 is attached to the lower surface of the upper slide 3 which is moved up and down by mechanical means 2.

Further, the lower slide 4 includes a
A penetrating hole is formed along the sliding direction of the
A rod-shaped inner ram 14 is provided to pass through the hole.

An inner punch 11A is attached to the tip of the inner ram 14, and a lower mold 11B is attached to the upper surface of the lower slide 4, which has a hole through which the inner punch 11A can pass. The lower slide 4 is fitted into a cylinder 8 formed at the bottom of the frame 1, and the inner ram 14 is fitted into a cylinder 9 formed independently below the cylinder 8 of the frame 1. It descends independently depending on the pressure.

On the other hand, separate hydraulic drive sources 12 and 13 are connected to the opposite side (lower part) of the cylinders 8 and 9 to the piston rod via piping 12A and 13A, respectively.
The lower slide 4 and inner ram 14 are moved toward the upper slide 3 side.

In the middle of the pipe 12A, a pressure adjusting means such as a relief valve or an intensifier is provided which can set the outflow pressure from the cylinder 8 side to an appropriate setting pressure, and the lower slide 4 is moved by the upper slide 3. When the inner ram 14 is pressed down, the closing pressure is maintained at a predetermined pressure.
The lower slide 4 can be moved back independently from the lower slide 4. In addition, a fluid blocking means such as a solenoid valve or the like is provided in the middle of the pipe 13A, and when the lower slide 4 is pushed down by the upper slide 3, the inner ram 14 blocks the fluid flow. A valve ensures that the lower slide 4 remains in place even when lowered.

By changing the closing pressure of the cylinder 8 of the slide 4, it is possible to change the ratio of the clamping force of the molds 10, 11B and the driving force of the inner punch 11A, and the impact of the inner punch 11A on the material. You can freely set the loading force.

For example, if the press has a capacity of 400T, adjust the relief valve etc. to increase the clamping force of molds 10 and 11B.
When setting it to 300T, the driving force of inner punch 11A is
If the mold clamping force is 200T, the driving force will be 200T.

FIG. 3 shows the state in which the forging material is charged into the lower mold 11B and the upper mold 10 is in contact with the lower mold 11B, and FIG. 4 shows the upper and lower molds 10, 11.
B descends with the mold clamped, and inner punch 1
1A is about to be inserted into the space between the upper and lower molds 10 and 11B. FIG.

Note that the lower slide 4 and the inner ram 14
When moving upward toward the slide 3, the slides 4 and inner rams 14 rise in synchronization with each other, and when forming is completed, the slides 4 and inner rams 14 descend to facilitate the insertion and removal of the forged product.

In the above configuration, one press cycle is performed as follows.

The forging material is charged into the lower die 11B.

A pressure medium is introduced into the lower portions of the cylinders 8 and 9 to raise the inner ram 14 and the lower slide 4 to a predetermined position, for example, to a position where the lower mold 11B is near the upper mold 10 almost simultaneously.

By mechanical means 2 (rotating the crankshaft 6) the upper slide 3 is lowered.

Even when the upper mold 10 reaches the lower mold 11B, the upper slide 3 continues to descend, so the lower slide 4 receives a downward force and is pushed down. At this time, the pressure medium in the lower part of the cylinder 8 is pushed out, but it is pushed down while keeping the pressure constant by a relief valve or intensifier with an appropriate set pressure in the middle of the piping, so the set closing load of the upper and lower molds 10, 11B can be obtained.

The mold 10 is closed due to the lowering of the upper slide 3,
When 11B descends, the inner ram 14 provided through the lower slide 4 moves the molds 10 and 11B.
the inner ram 14
The inner punch 11A attached to the inner punch 11A starts punching into the forging material in the closed mold.
That is, when the lower slide 4 descends, the pressure medium charged into the lower part of the cylinder 9 of the inner ram 14 has its circuit cut off by means such as a solenoid valve, and the escape route is blocked.
4 is unable to descend and remains in place.
Therefore, the inner punch 11 for the forged material
The driving force A is generated by the downward force of the upper slide 3.

Closed forging is thus started.

Eventually, the upper slide 3 reaches the bottom dead center, stops descending, and starts ascending.

On the other hand, the pressure medium is allowed to flow into the piston rod side (upper part) of the cylinders 8 and 9, and the pressure medium is allowed to flow out from the side opposite to the piston rod (lower part) of the cylinders 8 and 9, thereby lowering the lower slide 4 and the inner ram 14.

When the upper slide 3 reaches the top dead center, a brake is applied to the crankshaft 6 and the upper slide 3 stops.

In this way, one cycle ends.

[Effects of the Invention] The double-action press according to the present invention has the above-described configuration, has both the advantages of a mechanical press and a hydraulic press, and has the following effects.

(i) By making the lower slide and inner ram cylinders separate and setting the closing pressure of the lower slide cylinder to an appropriate setting pressure, it is possible to freely set the driving force of the inner punch into the forged material. .

This allows forging to be performed without being limited to the shape of the molded product.

(ii) A high-speed double-acting press can be obtained compared to a hydraulic press.

(iii) In a mechanical press, the stroke amount is the maximum gap between the upper and lower dies, so if a larger gap between the dies is required (a wider gap is required when removing the forged material with a robot, etc.) ), it is necessary to lengthen the frame itself to lengthen the press stroke, but in this application, in addition to the stroke amount of the upper slide, the lower slide and inner ram descend, so the dimension between the upper and lower molds is wider. This makes it easy to take the forging material in and out between the dies.

(iv) By housing the lower slide and inner ram in the press frame, it is possible to easily realize a double-acting forging press, which is almost impossible to design as a mechanical press in terms of space.

(v) Since the lower slide and inner ram are fitted into the cylinder so that they can move up and down, the stick problem that is a drawback of mechanical presses does not occur, and even if it occurs, the lower part of the lower slide and inner ram inside the cylinder does not occur. It can be easily released by letting the oil escape and lowering the lower slide and inner ram.

(vi) The pressure oil supplied to the cylinders 8 and 9 does not require a large amount of pressure to form a forged material, and the pressure oil supplied to the lower die 11B, the slide 4 and the inner ram 1
It is sufficient to have the pressure to lift the dead weight of 4.
Therefore, a low-pressure hydraulic pump may be used as long as the pressure is high enough to lift each member upward.
Moreover, when maintaining the closing pressure, the amount of oil that passes through pressure regulating means such as a relief valve or intensity ear is small, and the noise generated from the hydraulic pump or valve, which is a problem with hydraulic presses, can be reduced.

(vii) Slide adjustment (die height adjustment) required for mechanical presses is not required.

(viii) A hydraulic drive source that moves the lower slide and inner ram toward the upper slide, since the pressurizing force required for closed forging and the driving force of the punch into the forging material can be performed only by the pressurizing force of the upper slide. The power needed to move each of them to a predetermined position is sufficient and is economical.

[Brief explanation of the drawing]

FIGS. 1 and 2 are a vertical sectional view and a partially sectional side view showing a double-acting press according to the present invention, and FIGS. 3 and 4 are sectional views showing a forging process. DESCRIPTION OF SYMBOLS 1... Frame, 2... Mechanical means, 3... Upper slide, 4... Lower slide, 5... Gear,
6...Crankshaft, 6A...Cam, 7...
Eccentric body, 8, 9...Cylinder, 10...Upper mold,
11A...Inner punch, 11B...Lower mold,
12, 13...hydraulic drive source, 14...inner ram.

Claims (1)

[Claims] 1 Upper slide 3 that advances and retreats by mechanical means
and an upper mold 10 attached to the upper slide 3.
a cylinder 8 formed at the lower part of the frame 1 facing the upper slide 3; a lower slide 4 fitted into the cylinder 8; and a mechanism for retracting the lower slide 4 in response to movement of the upper slide. a pressure adjusting means for maintaining the closing pressure of the upper and lower molds; a lower mold 11B attached to the lower slide 4; a cylinder 9 formed downwardly by the cylinder 8 at the lower part of the frame 1; penetrates the mold 11B and the lower slide 4, and
an inner ram 14 fitted into the cylinder 9;
It includes a fluid blocking means for blocking the flow of fluid from the cylinder 9, and hydraulic drive sources 12 and 13 that generate hydraulic pressure for moving the inner ram 14, the lower slide 4, and the lower mold 11B upward. A mechanical hydraulic double-acting press characterized by: