JPH0663657A - Opposed hydraulic forming machine - Google Patents

Abstract

PURPOSE:To accurately perform pressure control and to attain a high speed for forming by providing a hydraulic control cylinder in a part of the hydraulic chamber of an opposed hydraulic forming machine. CONSTITUTION:A blank 20 is held on a die 6 by a blank holder 15, and a punch 18 is lowered for abutting on the blank 20 to perform drawing. Water 8 in the same volume as the punch 18 and the blank 20 plunging into the hydraulic chamber 4 is moved to a lower hydraulic chamber 5B through a port 10. Consequently, a movable ring 9 inside the pressure control chamber 5 is pushed up. The ring being directly connected to a cylinder device 11 structured in the lower part, a hydraulic pressure or a gas pressure is supplied to or drained from the lower chamber 11C of the cylinder device 11 so as to control the load over the movable ring 9, and the hydraulic chamber 4 is controlled for a prescribed pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an opposed hydraulic forming machine used for deep drawing a metal plate, for example.

[0002]

2. Description of the Related Art Generally, in order to form a metal plate into a predetermined shape, a means for pressing the metal plate with a pair of concave and convex molds is used. However, in order to obtain a deep-drawn product without cracks, all of the molds must be processed with high precision. For this reason, conventionally, for example, a method for forming a metal thin plate by opposing hydraulic pressure, which is found in Japanese Patent Publication No. 57-7809, has been provided.

This conventional structure is composed of a die having a hydraulic chamber, a blank holder which can be brought into contact with the die, and a punch which can be thrust into the hydraulic chamber through the blank holder. And a through hole for discharge is formed. Then, with the thin metal plate positioned between the die and the blank holder, the punch passed through the blank holder is brought into contact with the thin metal plate, the thin metal plate is narrowed down into the hydraulic chamber, and the liquid in the hydraulic chamber is passed through. The product is discharged from the hole and the opposing hydraulic pressure is applied to form the desired product with a complicated shape.

[0004]

However, in the above-mentioned conventional molding method, the pressure control of the hydraulic chamber is important and is also related to the blank holder pressure. In order to avoid breakage at the die shoulder or punch shoulder, the punch is used. Complex control by stroke is required. In addition, high-speed molding is required for high-mix low-volume production, but in conventional hydraulic circuit systems, turbulent flow occurs when the flow velocity of liquid discharged from the hydraulic chamber exceeds 3 to 5 ^M / _S. Since the waste heat in the pipe was large, the pressure loss was large, and accurate control was not possible at high speeds.

An object of the present invention is to provide a counter-hydraulic molding machine in which pressure control can be performed easily and accurately, and high-speed molding can be easily realized.

[0006]

In order to achieve the above object, an opposed hydraulic forming machine of the present invention comprises an opposed hydraulic device, a blank holder and a punch, and the opposed hydraulic device is a die on an upper part of a main body. In addition to forming a pressure chamber with an open upper surface in the center, a pressure adjusting chamber is formed on the outside of this pressure chamber via a partition wall, and a movable body that can be moved up and down is provided in this pressure adjusting chamber. Below the movable body, the hydraulic chamber and the pressure adjusting chamber are configured to communicate with each other, and a pressure setting device that interlocks with the movable body is provided outside the counter hydraulic device.

[0007]

According to the structure of the present invention, the blank holder is raised, the material is set on the die, and then the movable body is lowered by the operation of the pressure setting device. It can be moved to a hydraulic chamber to bring the water level in the hydraulic chamber to a predetermined position. In this state,
Lower the blank holder and press the material on the die with the specified load. The material can then be gradually drawn by lowering the punch.

While performing such drawing, the movable body is raised by the operation of the pressure setting device so that the hydraulic chamber has a predetermined hydraulic pressure in accordance with the punch stroke.
The liquid in the hydraulic chamber is moved to the pressure adjusting chamber. That is,
The movable body in the pressure adjusting chamber can be raised according to the amount of drawing processing. Therefore, even if the punch enters the hydraulic chamber at high speed, there is no problem in controlling the flow rate of the hydraulic chamber.

At this time, by controlling the operation of the pressure setting device while controlling the operation amount of the pressure setting device while detecting the operation amount, the pressure of the pressure adjusting chamber can be set and molding can be performed with an arbitrary counter hydraulic pressure. Further, by controlling the liquid volume of the hydraulic chamber by the pressure setting device, the volume can be reduced to 1/10 to 1/20, and as a result, the pressure setting device side can reduce the hydraulic system even in high-speed molding. Can be applied, the position of the movable body can be easily detected, and the water level of the hydraulic chamber can be easily adjusted. Then, by detecting the position of the movable body and the punch stroke, it is possible to grasp the molding state of the molded product,
The pressure control (load control) on the material can be performed, which facilitates the processing of deep drawing molded products or complex molded products.

Then, when the desired drawing process is completed,
By further raising the movable body by the operation of the pressure setting device and reducing the residual pressure in the pressure adjustment chamber to zero, raising the punch and the blank holder, and gradually lowering the movable body by the reverse operation of the pressure setting device, By moving the liquid from the pressure adjusting chamber to the hydraulic chamber, the drawn product can be lifted by buoyancy and taken out.

[0011]

An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 is an opposed hydraulic device, and a main body 2 thereof is formed in a bottomed cylindrical shape with an open upper surface. A cylindrical partition wall 3 is provided in the main body 2, whereby a hydraulic chamber 4 having an open upper surface is formed inside the partition wall 3 and a pressure adjusting chamber 5 is formed outside the partition wall 3. There is. A ring-shaped die 6 is provided between the upper portion of the main body 2 and the partition wall 3, and water 8 which is an example of a liquid is filled in the hydraulic chamber 4 including the central through hole 7 of the die 6. ing.

A movable ring 9, which is an example of a movable body, is provided in the pressure adjusting chamber 5 so as to be movable up and down. The movable ring 9 divides the pressure adjusting chamber 5 into an upper open chamber 5A and a lower hydraulic chamber 5B. Be divided. The lower hydraulic chamber 5B and the hydraulic chamber 4 are communicated with each other through a plurality of ports (through holes) 10 formed in the lower portion of the partition wall 3.

A cylinder device 11, which is an example of a pressure setting device, is interlocked with the lower portion of the movable ring 9. The cylinder device 11 is composed of a cylinder body 11A, an upward piston rod 11B, and the like, most of which is located below the counter hydraulic device 1 and the piston rod 11B is inserted through the bottom wall of the body 2. After that, it is connected to the lower part of the movable ring 9.

Hydraulic pressure or gas pressure is supplied to or discharged from the lower chamber 11C of the cylinder device 11. A detection device 12 for detecting the throttle amount (movement amount) by the cylinder device 11 is provided, and the detection device 12 is attached to the rack plate 13 provided on the fixed part side and the piston rod 11B and the rack plate 13 is provided. The encoder 14 and the like have a pinion that meshes with the teeth of the.

Reference numeral 15 denotes a blank holder which can be opposed to the die 6 and is formed in a ring shape with a through hole 16 in the center. The upper part of the blank holder 15 is connected to a cylinder type actuator 17 for raising and lowering the blank holder 15 and maintaining the lowered position. Central through hole 7 of the die 6
A punch 18 is vertically movable through the through hole 16.

The deep drawing in the above embodiment will be described below. First, the blank material (material) 20 is set on the die 6 in a state where the blank holder 15 and the punch 18 are raised by the operating device 17. Next, the movable ring 9 is lowered by the contraction movement of the cylinder device 11, whereby the water 8 in the lower hydraulic chamber 5B is moved (flowed) to the hydraulic chamber 4 through the port 10 and is moved in the hydraulic chamber 4. Set the water level in place.

In this state, the blank holder 15 is lowered by the operating device 17 to hold the blank material 20 on the die 6 with a predetermined load. Then, the punch 18 is lowered, and as shown in the left half of FIG. 1, the punch 18 is brought into contact with the upper surface of the blank 20 through the through hole 16 and the central through hole 7.
By lowering, the blank material 20 is gradually drawn as shown in the right half of FIG.

While the drawing process is being performed, the hydraulic chamber 4 is kept at a predetermined hydraulic pressure in accordance with the punch stroke (the volume in which the punch 18 and the blank 20 are projected into the hydraulic chamber 4). So that the cylinder device 11 is extended and the movable ring 9 is raised, whereby the water 8 in the hydraulic chamber 4 is moved.
Is moved to the lower hydraulic chamber 5B through the port 10. That is, the movable ring 9 in the pressure adjusting chamber 5 can be raised according to the drawing amount, and therefore even if the punch 18 enters the hydraulic chamber 4 at high speed, there is a problem in controlling the flow rate of the hydraulic chamber 4. There is no.

At this time, the amount of extension movement of the cylinder device 11 can be detected by the encoder 14 acting on the rack plate 13,
Therefore, by controlling the extension while grasping the detected value, the pressure of the lower hydraulic chamber 5B can be set, so that molding can be performed with an arbitrary counter hydraulic pressure. Further, as described above, the hydraulic chamber 4
By controlling the liquid volume control of the cylinder device 11 with the cylinder device 11, the volume can be reduced to 1/10 to 1/20, and as a result, even in the high speed molding, the conventional hydraulic system has the cylinder device 11.
Applicable on the side. Further, by providing the cylinder device 11, the position of the movable ring 9 can be easily detected, and the water level of the hydraulic chamber 4 can be easily adjusted.

By detecting the position of the movable ring 9 and the punch stroke by the detection device 12, the molding state of the molded product can be grasped, and the pressure control (load control) of the blank holder 15 can be performed. Easily process draw-formed products or complex molded products.

Then, when the desired drawing process is completed,
The movable ring 9 is further raised by the extension movement of the cylinder device 11 to make the residual pressure in the lower hydraulic chamber 5B zero. Then, after raising the punch 18 and the blank holder 15, the movable ring 9 is gradually lowered by the contraction movement of the cylinder device 11 to move the water 8 from the lower hydraulic chamber 5B to the hydraulic chamber 4 and squeeze it. The molded article can be lifted by buoyancy.

[0022]

According to the present invention having the above-mentioned structure, the position of the movable body can be controlled by operating the pressure setting device so that the hydraulic chamber has a predetermined hydraulic pressure during the drawing process. This makes it possible to easily and accurately control the liquid volume in the hydraulic chamber with a pressure setting device, reduce the drainage volume at high pressure, and speed up the counter hydraulic pressure to achieve high-speed molding. Can be easily realized. Further, by providing the pressure setting device, the position of the movable body can be easily detected and the water level of the hydraulic chamber can be easily adjusted.

By detecting the position of the movable body and the punch stroke, the molding state of the molded product can be grasped and the pressure control (load control) on the material can be performed. It is possible to easily process various molded products.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an opposed hydraulic molding machine according to an embodiment of the present invention.

[Explanation of symbols]

 1 Opposed hydraulic device 2 Main body 3 Partition wall 4 Hydraulic chamber 5 Pressure adjustment chamber 5B Lower hydraulic chamber 6 Die 8 Water (liquid) 9 Movable ring (movable body) 10 Port 11 Cylinder device (pressure setting device) 12 Detection device 15 Blank holder 18 Punch 20 Blank material

Claims (1)

[Claims] 1. A counter hydraulic device comprising a counter holder, a blank holder and a punch, wherein the counter hydraulic device is provided with a die at an upper part of a main body and a hydraulic chamber having an open upper surface at a central portion thereof. A pressure adjusting chamber is formed on the outside of the chamber via a partition wall, and a movable body that can be moved up and down is provided in the pressure adjusting chamber, and the hydraulic chamber and the pressure adjusting chamber are connected under the movable body. The counter hydraulic forming machine is characterized in that a pressure setting device interlocking with the movable body is provided outside the counter hydraulic device.