JP2713111B2 - Detonation molding method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for improving the function of impact molding by adding a molding step by static high pressure to a molding method and apparatus utilizing gas detonation due to detonation. It relates to a device for that.

[0002]

2. Description of the Related Art An apparatus applicable to both static pressure molding and impact pressure molding to which the present invention is applied has not yet been found.
Numerous studies have been conducted on the technology of static pressure molding or impact pressure molding alone since ancient times, and there is a track record as an actual production facility. In particular, as for a static pressure forming device, a device using hydraulic pressure has been widely used.

On the other hand, impact molding apparatuses are used only in part because explosives are often used, but an impact hydraulic molding technique is known as a typical technique. For example, a bullet is injected into a liquid such as water for pressurization to generate an impact liquid pressure in the liquid, and the pressure is applied to a member such as a plate material to press the member into a mold to form a three-dimensional molding. An impact hydraulic pressure generator as proposed in Japanese Patent Application Laid-Open No. 01-157725, an impact water pressure is generated by burning an explosive in water, and a molding device for three-dimensionally forming a thin plate with the pressure, Impact liquid pressure is generated by colliding a piston accelerated at high speed by gas pressure or the like against the liquid surface of the pressurizing liquid stored in the container,
There is a device that performs three-dimensional molding under the pressure.

However, in these devices,
The shape or size of the hydraulic chamber needs to be determined in consideration of the behavior of the energy source (explosive, high-speed projectile), the degree of freedom is very small, the duration of pressure is long, and the relative pressure in the hydraulic chamber is relatively small. In addition to common problems such as simultaneous application of impact pressure over a wide range, the need to consider installation restrictions or safety considerations due to the danger, etc., it also has unique problems .

[0005] In order to solve these problems, the applicant has proposed a detonation hydraulic pressure forming method and apparatus disclosed in, for example, Japanese Patent Application Laid-Open No. 04-371327.

In this apparatus, the combustion chamber has an inverted conical shape, and the cross-sectional area is set so as to gradually decrease from one end as the flame progresses, and the converging portion has a minimum passage cross-sectional area at the other end. Is formed, and the liquid surface of the hydraulic chamber faces the opening at the other end. As the flame in the combustion chamber progresses, the cross-sectional area of the combustion chamber becomes smaller and the pressure rises, and the pressure at the other end becomes extremely high. This high pressure is converted to the liquid pressure of the liquid in the hydraulic chamber. If a processing chamber having a mold is provided in the hydraulic chamber, and a workpiece such as a plate material is disposed on the mold, the workpiece is processed into a predetermined shape by the hydraulic pressure. Can be. The hydraulic chamber may be a resilient chamber having a rubber-like elastic body instead of the liquid.

[0007]

Here, for example, when it is desired to subject a workpiece to static pressure molding and then perform impact pressure molding, in the prior art, the above-described process is performed using two static pressure molding apparatuses and an impact pressure molding apparatus. It is not only necessary to carry out the process separately, it is not only time-consuming to put the work into and out of each molding device, but also high equipment cost and running cost, cycle time cannot be set short, and danger in equipment operation In addition, there are problems such as an increase in machining accuracy, and a reduction in machining accuracy due to resetting of the workpiece, and the like, and it is difficult to actually apply the method.

Further, the following problems can be cited as problems of the conventional detonation hydraulic forming apparatus itself.

When the speed at which the workpiece is deformed by receiving the impact pressure (deformation speed) becomes equal to or higher than the sound velocity in the gas in contact with the front surface of the workpiece, the speed is reduced during molding. The gas in front of the workpiece is compressed, and this becomes the deformation resistance of the workpiece (particularly, in the case of thin plate forming, this phenomenon has a significant effect on the formability). Since the pressure strongly depends on the propagation distance of the shock wave, it is essentially impossible to avoid the influence of the shape and installation position of the sample.

However, simply adding a hydraulic (static) pressure applying device for increasing the pressure to the detonation hydraulic forming device has the following problem. Can not get.

[0011] Even if an attempt is made to increase the pressure in the hydraulic chamber by applying a static external force to the liquid in the hydraulic chamber of the detonation hydraulic forming apparatus, the pressure is increased because the converging portion of the combustion chamber remains open. The elastic body does not rise because it escapes to the side (even when the elastic body is filled in the hydraulic chamber, a phenomenon similar to that in the case of a liquid occurs above the pressure level at which the elastic body is plastically deformed).

As a measure against the above, for example, it is conceivable to install a valve at the converging portion of the combustion chamber. However, since the valve itself is directly exposed to high temperature and high pressure, a valve having a general structure and material cannot withstand repeated use. I can't.

Although it is possible in principle to pressurize the hydraulic chamber or the repressing chamber by pressurizing with gas from the combustion chamber side, the equipment cost rises at 10 atm or more because the high pressure gas control method is applied. In addition, there are restrictions on installation and operation of equipment.

The present invention solves the problems associated with the conventional method and apparatus, and provides an explosion utilizing gas converging detonation that can easily and safely perform static pressure molding and impact molding with one apparatus. It is an object of the present invention to provide a molding method and apparatus by roar.

[0015]

SUMMARY OF THE INVENTION According to the present invention, there is provided a molding method, comprising: a direct or exchangeable membrane for impact high pressure due to convergent detonation generated by igniting a combustible mixture in a combustion chamber. In a method of transmitting a pressure fluid or an elastic pressure through a body or a fluid to a pressure medium to generate an impact hydraulic pressure or an elastic pressure and pressing a workpiece to a molding die to form the workpiece, the method includes applying an external static high pressure to the pressure medium, This is achieved by applying a high impact high pressure.

Alternatively, the impact high pressure due to convergent detonation generated by igniting the combustible air-fuel mixture in the combustion chamber is transmitted to the pressure medium directly or via a replaceable membrane or fluid to reduce the impact hydraulic pressure or the elastic pressure. In the method of generating the workpiece and pressing the workpiece to a molding die, the method is also achieved by applying a high static pressure from outside after applying a high impact pressure to the pressure medium.

Further, with respect to an apparatus for carrying out the above method, a combustion chamber in which the cross-sectional area of the passage decreases from one end to the other end, an ignition chamber which receives fuel and is provided with an ignition plug, A plurality of guide paths having the same path extending from the ignition chamber and communicating with one end of the combustion chamber, and the opening and closing of the opening by opening and closing near the opening at the other end which is the minimum passage sectional area of the combustion chamber. A block body is installed, and on the downstream side,
A pressure chamber in which a liquid and an elastic body are accommodated as a pressure medium, a molding chamber connected to the pressure chamber to accommodate a workpiece therein, and a static external force applied to the liquid in the pressure chamber. This is achieved by providing a static pressure applying device.

[0018]

According to the present invention having such a structure, the pressure obtained by gas detonation is converged to become a high-impact pressure and propagated into the pressure chamber. Works. Before or after the application of the impact pressure, the opening between the combustion chamber and the pressure chamber is closed with a block, and an external force is applied to the liquid in the pressure chamber to apply a static high pressure to the workpiece in the pressure chamber. Thus, the forming of the workpiece can be performed. The static pressure molding and the impact pressure molding are carried out by a control device in consideration of the pattern (order, number of times, and the like) of the material to be processed, the thickness of the workpiece, the shape of the molding die, and the like.

Thus, both impact pressure molding and static pressure molding can be performed by one apparatus, and the workpiece is subjected to impact pressure molding after impact pressure molding, or impact molding after static pressure molding, or These patterns are applied repeatedly.

[0020]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view of the apparatus according to the first embodiment of the present invention, and FIG. 2 is an enlarged longitudinal sectional view of a pressure chamber and a molding chamber of the apparatus shown in FIG. As shown in FIG.
The combustion chamber 1 has an inverted conical shape narrowing downward, and the cross-sectional area of the passage in the cross section is maximum at the upper end 1A and minimum at the lower end 1B to form a converging portion. ing.

The inner wall of the upper end portion 1A of the combustion chamber 1 is slightly curved upward, and a plurality of hole-shaped guide paths 2 communicate therewith. The plurality of guide paths 2 are converged on the upper side into a dispersion space 3 having a disc shape. An ignition chamber 4 extending upward is communicatively connected to the dispersion chamber 3. An ignition plug 5 operated by an ignition device 6 is provided at an upper portion of the ignition chamber 4, and a fuel supply source 9 and an oxidant supply source 10 are connected via flow meters 7 and 8, respectively. . Reference numeral 11 denotes a pressure gauge for checking the pressure in the ignition chamber 4.

As shown in FIG. 2, at the lower end 1B of the combustion chamber 1, there is provided a retractable block body 20 for forming or closing an opening, and a drive unit 21 for moving the block body. And a passage 1 for supplying a sealing liquid or discharging an excess liquid to the opening.
4 and 14 'are provided. A pressure chamber 12 is connected to the opening, and a molding chamber 13 using an impact pressure is provided immediately below the pressure chamber 12. The pressure chamber 12 accommodates a liquid or rubber-like elastic body G as a pressure medium, and further includes a static pressure applying device 1 such as a pump in a space below the elastic body G.
The liquid E for applying a static pressure applied by the reference numeral 5 is stored. A molding chamber 13 for accommodating a mold 16 for supporting the plate material P as a workpiece is provided below the molding chamber 13.

When generating an impact pressure, the block 20
When the lower end 1B is to be opened by immersing the lower end 1B, the upper end surface of the pressure medium G may directly face the lower end 1B of the combustion chamber 1 as shown in FIG. The interface may be formed by a liquid or a tough and deformable film body.

On the other hand, when applying a static high pressure to the plate material P and closing the opening 1B by projecting the block body 20, the liquid E in the pressure chamber 12 is pressurized by the static pressure applying device 15 described above. I can do it. Inside the molding chamber 13, a mold 16 having a molding surface for three-dimensional molding formed on its upper surface is exchangeably accommodated. If necessary, the molding chamber 13 can hold, for example, the periphery of a plate material or the like P as a workpiece to be processed between the two flanges, between the pressure chamber 12 and the pressure chamber 12. The molding chamber 13 is connected to a vacuum pump device 17 which penetrates the mold 16 and communicates 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, for example, after the primary molding is performed by applying an impact pressure, the final molding is performed by the static pressure as follows.

First, a plate material P to be processed is placed in a mold 1.
6, the block 20 is pulled back by operating the driving device 21, the lower end 1B is opened, and the liquid is filled from the passage 14 into the opening. At that time, the liquid enters the gap on the peripheral surface of the block body 20 to seal and
Protect 0 from high temperature environment.

Next, the interior of the ignition chamber 4, the dispersion chamber 3, the guide path 2, and the interior of the combustion chamber 1 are set 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 similarly suctioned so as to have a predetermined degree of vacuum.

Thereafter, the pressure chamber 12 is filled with a liquid or an elastic body, and the ignition chamber 4, the dispersion chamber 3, the induction path 2, and the combustion chamber 1 contain a flammable gas having a substantially stoichiometric mixture. The supply source 9 is filled with an oxidant supply source 10.

After the setting is completed, the ignition plugs 5 are simultaneously operated by the ignition chamber 6. A detonation occurs in the ignition chamber 4 due to the ignition, and the flame is propagated to the upper end 1A of the combustion chamber 1 through the dispersion chamber 3 and the guide path 2. At this time, since the paths of the plurality of taxiways 2 are set to be equal to each other, the flames of the plurality of taxiways 2 are simultaneously heated at the upper end 1.
A is reached.

In the combustion chamber 1, the flame proceeds from the upper end 1A to the lower end 1B. However, since the cross-sectional area of the passage of the combustion chamber 1 gradually decreases downward, the pressure increases and the lower end 1B Then, the pressure becomes extremely high.

Since the upper end surface of the pressure medium in the pressure chamber 12 faces the opening of the lower end portion 1B of the combustion chamber 1, the high pressure is transmitted to the pressure medium and is transmitted through the membrane or directly. First, the sheet material P is pressed against the mold 16 in the molding chamber 13 to perform primary molding.

Next, after the drive unit 21 is operated to project the block body 20 to close the opening 1B, the liquid in the pressure chamber 12 is pressurized using the static pressure applying device 15 to statically press the plate material P. After the final molding is performed by applying a high pressure, the pressure of the liquid is reduced to the atmospheric pressure using the static pressure applying device 15. When the block body 20 receives the pressure from the elastic body G of the pressure chamber 12, the block body 20 is pressed by the elastic body G to have a sealing function.

Thereafter, a sheet material as a molded product is taken out, and the above-mentioned steps (1) to (5) are repeated, whereby products can be formed one after another.

The above procedure is for performing static pressure forming after impact pressure forming by detonation, but in order to perform this in reverse, the above steps must be performed prior to the above steps. Whether the static pressure molding is performed before or after the impact pressure molding is appropriately determined depending on conditions such as the material of the workpiece and the workability. For example, if the workpiece is a high-speed ductile material (JIS 5052 H34, SUS 301
In the case of (1), cracks and the like occur if static pressure molding is performed first, so it is better to perform static pressure molding after detonation impact molding. For general materials, static pressure molding may be performed first.

Next, a second embodiment of the present invention will be described with reference to FIG. In the drawing, the same reference numerals are given to the same components as those of the apparatus of the previous embodiment shown in FIG.

In the present embodiment, the combustion chamber 1 'is formed in a horizontal shape extending in the radial direction. The combustion chamber 1 'has a shape in which the cross-sectional area decreases toward the center by the upper wall surface of a part of a substantially spherical surface which bulges downward.

According to the apparatus of this embodiment, it is convenient when the dimensions of the apparatus cannot be increased. The operation is the same as in the previous embodiment. After the flame reaches the peripheral portion 1'A, which is one end of the combustion chamber 1 ', from the guide path 2, the flame travels toward the central portion 1'B, which is the other end. proceed. As it proceeds, the pressure becomes very high as the cross-sectional area decreases. Then, the high pressure is propagated to the pressure medium in the pressure chamber 12. For example, in the molding chamber 13, the plate material P is pressed against the mold 16 to perform primary molding, and the same operation as described above is performed to statically form the plate material. Final molding is performed by applying high pressure.

[0039]

As described above, according to the present invention, the function of impact molding utilizing gas convergent detonation and the function of applying static pressure in a pressure chamber using a static pressure applying device with the opening between the combustion chamber and the pressure chamber closed. The function of generating static high pressure and performing static pressure molding can be realized by a single device, and a control device is provided so that these two functions can be formed independently or in conjunction with each other. In addition, compared to the conventional method, the facility cost and the running cost become easier, and there is no work such as relocating the workpiece, so that it is possible to realize an inexpensive, easy, and short-time repetitive operation. .

By the way, when the present invention is viewed from the viewpoint of formability, it is possible to improve deep drawability, which is a drawback of impact molding, by static pressure molding. By performing only deformation or local deformation by impact molding, the problem of residual air in the mold during impact molding and the problem of non-uniformity of pressure distribution based on the difference in shock wave propagation distance can be ignored. As a result, it is possible to perform precision molding.

Further, according to the apparatus of the present invention, as a means for obtaining a static high pressure, a liquid pressure is used instead of employing a gas pressure, and a liquid is disposed only in the vicinity of a workpiece to be subjected to static pressure forming. Since it is enough to perform the operation, it is possible to obtain an effect that the operation can be safely and repeatedly performed in a short time.

Further, according to the apparatus of the present invention, since the static pressure and the impact pressure can be applied in an arbitrary pattern while the work to be processed is set, the dimensional accuracy of the work to be formed (particularly, a thin plate) (Important in the case of molding). In addition, the opening and closing of the opening between the combustion chamber and the pressure chamber is performed by a combination of a resilient metal block and a rubber-like elastic body or a liquid, so that sufficient durability and reliability can be maintained. Also get the effect.

Further, according to the apparatus of the present invention, since explosives are not used as a means for impact molding as in the conventional bullet driving type and explosive type, the apparatus is not restricted in setting, and the apparatus can be used for film formation. If a method of transmitting a pressure wave to the workpiece through the body is adopted, the handling of the workpiece can be facilitated, the processing can be performed continuously, and the effect of being diverted to a mass production system can be obtained. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an apparatus according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a pressure chamber and a molding chamber of the apparatus in FIG.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combustion chamber 1A One end 1B Other end (opening) 2 Guideway 4 Ignition chamber 5 Ignition plug 12 Pressure chamber 13 Molding chamber 15 Static pressure applying device 16 Mold 18 Control device 20 Block body 21 Drive device E Liquid G Elasticity Body P Workpiece

Claims (6)

(57) [Claims] An impact high pressure caused by convergence detonation generated by igniting a combustible mixture in a combustion chamber,
In a method of directly or directly exchanging a film or a fluid through a fluid to a pressure medium to generate an impact hydraulic pressure or an elastic pressure and press a workpiece to a molding die to form the work piece, A method for forming by detonation, comprising applying the high impact pressure after applying a high pressure. 2. An impact high pressure caused by convergence detonation generated by igniting a combustible mixture in a combustion chamber,
In the method of directly or directly exchanging a film or a fluid through a fluid to a pressure medium to generate an impact hydraulic pressure or an elastic pressure and press a workpiece to a molding die to form the workpiece, an impact high pressure is applied to the pressure medium. A detonation molding method characterized by applying a static high pressure from outside later. 3. A combustion chamber having a passage cross-sectional area decreasing from one end to the other end, an ignition chamber provided with an ignition plug receiving fuel supply, and a branch extending from the ignition chamber. A plurality of guide paths having the same path communicating with one end are provided, and a block body is provided near the opening at the other end, which is the minimum passage cross-sectional area of the combustion chamber, and is capable of opening and closing the opening. A pressure chamber for containing a liquid and an elastic body as a pressure medium therein, a molding chamber connected to the pressure chamber for containing a workpiece therein, and applying a static external force to the liquid in the pressure chamber. A detonation molding device with a possible static pressure application device. 4. The molding apparatus according to claim 3, further comprising a control device for setting the application timing by individually or in conjunction with the high impact pressure and the high static pressure. 5. The block body is arranged such that, when the opening is closed by the block body, the elastic body is pressed against the block body as the pressure in the pressure chamber increases, and the pressure chamber is pressed by the elastic body. The molding device by detonation according to claim 3, wherein the device forms a closed state. 6. When forming an opening by immersing a block body,
The molding by detonation according to claim 3, wherein a sealing chamber is provided so as to form a part of the pressure medium and seal around the block body by filling the opening with a sealing liquid. apparatus.