JPH04371327A - Method and device for forming by detonation hydraulic pressure - Google Patents

Abstract

PURPOSE:To form by converting a detonation gas pressure to a hydraulic pressure and pressing a member to be formed against a die by means of the hydraulic pressure. CONSTITUTION:A combustion chamber 1 is set as the cross-sectional area becomes gradually smaller from one end part 1A as a flame progresses, a convergent part having the minimum cross-sectional area is formed at the other end part 1B, and the liquid level of a hydraulic chamber 12 is located at the opening of the other end part 1B. As the flame inside the combustion chamber 1 progresses, the cross-sectional area of the combustion chamber is made smaller, and a pressure is built up to be extremely high at the other end part 1B. This high pressure is converted to a liquid inside the hydraulic chamber. A forming chamber 13 is provided in communication with the hydraulic chamber, and a forming die 16 supporting the member P to be formed is stored in the forming chamber 13.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding method using detonation hydraulic pressure, which can easily obtain high impact hydraulic pressure, and an apparatus therefor.

0002

[Prior Art] Three-dimensional forming, which is performed by applying hydraulic pressure to the other side of a workpiece such as a plate supported by a mold, is an instantaneous but extremely high-pressure forming process. In some cases, it may be preferable to Conventionally, several methods are known for such molding using hydraulic pressure.

For example, first of all, a bullet is fired into a pressurizing liquid such as water to generate an impact liquid pressure in the liquid.
An impact hydraulic pressure generator has been proposed in JP-A-01-157725, which applies this pressure to a member to be formed, such as a plate material, and presses the member into a mold for three-dimensional forming.

[0004] Secondly, there is also known an explosive molding device that generates impact water pressure by burning explosives in water, and uses the pressure to press a thin plate as a molded member against a mold to perform three-dimensional molding. ing. This equipment is mainly used for molding large parts.

Thirdly, a piston accelerated by gas pressure or the like collides with the surface of a pressurizing liquid contained in a container to generate an impact liquid pressure.
There is also known an apparatus in which a member to be molded is pressed against a mold using the hydraulic pressure and molded. The apparatus is used for molding relatively small parts.

[0006]

However, the above-mentioned methods of forming using impact hydraulic pressure using the first to third apparatuses have the following common or individual problems. 1. The whole or part of the inner wall of the container is directly exposed to high temperature and high pressure fields. 2. Using dangerous and expensive explosives. 3. To make a loud noise. 4. Due to the danger involved, there are restrictions on where it can be installed. 5. It is difficult to significantly change the ultimate pressure. 6. Not suitable for repeated operation over short periods of time. 7. Requires large-scale equipment. 8. Moving parts such as pistons must be replaced. 9. 10. The pressure lasts for a long time, causing great damage to the mold. Solid matter remaining in the hydraulic chamber. 11. The structure of the device is complex, making maintenance and inspection difficult. 12. Only one impact water pressure can be obtained in one shot.

That is, in the first method described above, 1
~6,8,9~12, 1~7,9,10 in the second method
, 12, and in the third method 1, 4 to 9, 11, 12
It has the following disadvantages.

[0008] The present invention solves the problems caused by the conventional methods described above, and provides a detonation hydraulic molding method that is safe, can be repeatedly operated in a short time, and can perform molding at high speed, and an apparatus therefor. The purpose is to

[0009]

[Means for Solving the Problems] According to the present invention, the above-mentioned object is firstly achieved by converging detonation waves generated by igniting a combustible air-fuel mixture as they progress in a forming method using detonation hydraulic pressure; This is achieved by transmitting the high pressure obtained at the convergence part to a liquid and converting it into liquid pressure, and using the liquid pressure to press the member to be molded into a mold through a membrane or directly to mold it.

[0010] The apparatus for carrying out the above method includes a combustion chamber whose cross-sectional area becomes smaller from one end to the other, an ignition chamber which receives fuel supply and is provided with an ignition plug, and an ignition a plurality of guiding paths having equal path lengths that branch out from the combustion chamber and communicate with one end of the combustion chamber; a hydraulic pressure chamber connected to an opening at the other end that is the smallest cross-sectional area of the combustion chamber; The molding chamber is provided with a molding chamber that communicates with the molding chamber, and the molding chamber houses a molding die that supports a molded member that receives hydraulic pressure either through a membrane or directly.

[0011]

[Operation] In the present invention, molding is carried out in the following manner. ■ First, the combustion chamber, guideway, and ignition chamber, which are in communication with each other, are filled with a combustible gas mixture at a nearly stoichiometric ratio. ■ Next, ignite it in the ignition chamber. ■ When ignited, the flame travels through the combustion chamber through a guide path due to detonation. At this time, since each guide path has the same path length, the flames of each guide path reach one end of the combustion chamber at the same time. (2) In the combustion chamber, the flame propagates toward the other end, but since the cross-sectional area of the combustion chamber decreases toward the other end, the flame pressure increases and reaches its maximum value at the other end. A hydraulic chamber is connected to the opening at the other end, and the liquid level faces the opening, so the pressure is transmitted to the liquid within the hydraulic chamber. (2) The pressure of the liquid in the hydraulic pressure chamber presses the molded member on the mold against the mold through the membrane body or directly, and molding is performed by press working.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view of a first embodiment of the apparatus of the present invention. In the figure, reference numeral 1 denotes a combustion chamber, which has a conical shape facing downward, and has a cross-sectional area that is maximum at the upper end 1A and minimum at the lower end 1B, forming a converging section.

The inner wall of the upper end 1A of the combustion chamber 1 is curved slightly upward, and a plurality of hole-shaped guide passages 2 communicate therewith. The plurality of guide paths 2 are converged upward into a disc-shaped dispersion chamber 3. An ignition chamber 4 extending upward is connected to the dispersion chamber 3 in communication. An ignition plug 5 operated by an ignition device 6 is provided in the upper part of the ignition chamber 4, and is connected to a fuel supply source 9 and an oxidizer supply source 10 via flowmeters 7 and 8, respectively. . Note that 11 is a pressure gauge for checking the pressure inside the ignition chamber 4.

The lower end 1B of the combustion chamber 1 is open, a hydraulic pressure chamber 12 is connected thereto, and a molding device 13 using hydraulic pressure is provided directly below the lower end 1B. A liquid such as water as a pressure medium is concentrated in the hydraulic pressure chamber 12, and the liquid level is at the lower end 1B of the combustion chamber 1 as shown in the figure.
The intervening surface may face directly or may be formed of a strong and easily deformable membrane. A pipe 14 for air venting is connected to the hydraulic pressure chamber 12 via a valve, and a liquid supply device 15 such as water for hydraulic pressure is connected via the valve.

The molding device 13 has a replaceable mold 16 therein whose upper surface has a three-dimensional shape for molding. If necessary, the forming device 13 can also hold the periphery of a plate material or the like P as a member to be formed between the flanges of the two, for example, between the hydraulic pressure chamber 12 and the hydraulic pressure chamber 12. A vacuum pump device 17 is connected to the molding device 13 for passing through the mold 16 and communicating with the upper space thereof to evacuate the space. The vacuum pump device 17
is also connected to the ignition chamber 4 described above.

In the apparatus of this embodiment, generation of high hydraulic pressure and molding using this are performed as follows. (1) First, the plate material P to be formed is set on the mold 16. (2) Next, the ignition chamber 4, dispersion chamber 3, guide path 2, and combustion chamber 1 are brought to a predetermined degree of vacuum by the vacuum pump device 17. At the same time, the space between the mold 16 and the plate material P is also suctioned to a predetermined degree of vacuum. ■ After that, the hydraulic chamber 12 is filled with liquid such as water, and the ignition chamber 4, dispersion chamber 3, guideway 2, and combustion chamber 1 are filled with flammable gas at a nearly stoichiometric mixing ratio. source 9 and oxidizer source 10. (2) After completing such settings, the ignition plug 5 is activated by the ignition device 6. In the ignition chamber 4, ignition causes a detonation, and the flame passes through the dispersion chamber 3 and the guide path 2 to the upper end 1 of the combustion chamber 1.
Propagated to A. At this time, since the distances of the plurality of guideways 2 are set to be equal, the flames of the plurality of guideways 2 reach the upper end portion 1A at the same time. ■ Inside the combustion chamber 1, the flame advances from the upper end 1A to the lower end 1B, but since the cross-sectional area of the combustion chamber 1 gradually decreases downward, the pressure rises and becomes extremely high at the lower end 1B. becomes. - Since the surface of the liquid in the hydraulic pressure chamber 12 faces the opening of the lower end 1B of the combustion chamber 1, the high pressure is propagated from the liquid surface into the liquid, through the membrane or Forming is performed by directly pressing the plate material P against a mold 16 of a forming device under equal pressure. (2) Thereafter, by taking out the plate material as a molded product and repeating the steps (1) to (3) above, molding can be performed one after another.

FIG. 2 specifically explains the detonation hydraulic pressure in this embodiment using numerical values. The figure shows the results of pressure measurement near the liquid level facing the other end 1B of the combustion chamber 1. When the gas pressure at the center of the combustion chamber was 370,000 atm, the liquid pressure was generated for about 15 μsec. During that time, primary and secondary waves were obtained. The primary wave is 3200kgf/cm2
, the secondary wave was 3500 kgf/cm2. In addition,
This pressure can be easily adjusted by adjusting the gas pressure (amount) and mixture ratio filled into the combustion chamber.

Next, a second embodiment of the present invention will be explained based on FIG. In the figures, parts common to those of the previous embodiment shown in FIG. 1 are given the same reference numerals, and their explanations will be omitted.

In this embodiment, the combustion chamber 1' is formed in a horizontal shape that expands in the radial direction. The combustion chamber 1' has a cross-sectional area that decreases toward the center due to the upper wall surface of a portion of a substantially spherical surface that swells downward. On the upper wall surface, an appropriate number of grooves 1'C are formed radially toward the center,
A combustion chamber 1' communicates with a hydraulic chamber 12 at the center.

The apparatus of this embodiment is convenient in cases where the size of the apparatus cannot be increased. The operation is the same as in the previous embodiment, and the flame flows from the guide path 2 to the combustion chamber 1.
After reaching the peripheral part 1'A, which is one end of ', it advances toward the center part 1'B, which is the other end. During its progression, the pressure becomes extremely high as the cross-sectional area decreases. The high pressure is then propagated to the liquid in the hydraulic chamber 12, and the molding device 13 presses the plate material P against the mold 16 to perform molding.

[0022]

[Effects of the Invention] Since the present invention is configured as described above,
With this method, compared to conventional methods, it is possible to perform impact hydraulic molding with a steep rise and excellent properties at a lower cost and more easily. Since the method is dependent on

Furthermore, since the device of the present invention does not use gunpowder unlike the conventional bullet-driving type and explosive type, the device is not subject to any restrictions on settings, and it is capable of continuously generating impact hydraulic pressure. This has the effect that it can be used in mass production systems.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of a hydraulic pressure waveform in the device of FIG. 1;

FIG. 3 is a sectional view of the device of the second embodiment.

[Explanation of symbols]

1 Combustion chamber 1’　Combustion chamber 1A One end (upper end) 1’A　One end (periphery) 1B Other end (lower end) 1’B Other end (center) 2 Taxiway 4 Ignition chamber 5. Spark plug 12 Hydraulic pressure chamber 13 Molding room (molding equipment) 16 Molding mold P　Part to be formed

Claims (2)

[Claims] Claim 1: A detonation wave generated by igniting a flammable air-fuel mixture is converged as it progresses, and the high pressure obtained at the convergence part is transmitted to the liquid and converted into liquid pressure, and the membrane body is moved by the liquid pressure. A molding method using detonation hydraulic pressure, in which the part to be molded is pressed into a mold either through or directly. 2. A combustion chamber whose cross-sectional area decreases from one end to the other; an ignition chamber that receives fuel and is provided with an ignition plug; and one end of the combustion chamber that branches off from the ignition chamber and extends. a plurality of guiding passages having equal path lengths communicating with the combustion chamber, a hydraulic pressure chamber connected to an opening at the other end of the combustion chamber that is the smallest cross-sectional area, and a molding chamber communicating with the hydraulic pressure chamber; A molding device using detonation hydraulic pressure, in which a molding die supporting a molded member that receives hydraulic pressure directly or through a membrane body is housed in a molding chamber.