JPH09122993A - Dry process isostatic pressure molding device and dry process isostatic pressure molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to shorten restoration time and to improve molding efficiency by introducing compressed air into a rubber mold for molding at the time of taking out a molding by restoring the rubber mold for molding, thereby accelerating the restoration of the rubber mold for molding and the outflow of a pressure medium. SOLUTION: The supply of the compressed air is executed by allowing the pressure medium to flow out of itself from a pressure medium outlet 30 and/or pressure medium inlet to drop the pressure after the end of pressurization, then removing a top punch 11 and inserting a compressed air introducing pipe 45 into a hole part 13 disposed at a pressure vessel 2. The inside wall of the hole for fitting and mounting the top punch 11 to the pressure vessel 2 is provided with an aperture to supply the compressed air in order to save the labor for removing the top punch 11 and inserting the compressed air introducing pipe 45 at the time of supplying the compressed air. The restoration of the rubber mold for molding at the time of a pressure reduction is rapidly executed in such a manner, by which the molding efficiency is improved.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a dry hydrostatic pressure molding apparatus and a dry hydrostatic pressure molding method for molding, for example, ceramic powder, metal powder, or the like.

[0002]

2. Description of the Related Art Generally, dry isostatic pressing (hereinafter referred to as CIP molding) comprises powder filling, pressurization, depressurization, and molding removal, and is suitable for molding ceramic powder, metal powder, and the like. Used for.

The molding process by CIP molding will be described with reference to FIGS. 7 to 10 by taking as an example the molding of a bottomed cylindrical body. First, as shown in FIG. 7, molding powder A such as ceramic powder or metal powder is inserted and filled into the molding space 8 in the pressure container 2 via the powder supply nozzle 1. Here, the pressure vessel 2
Has a molding space 8 formed therein with a columnar mandrel 3, a cylindrical molding rubber die 4, and a bottom punch 9 that supports the mandrel 3 from below. A pressure medium sealing rubber 5 that surrounds the molding rubber die 4 is provided on the outer peripheral side. A pressure medium inlet / outlet 6 is provided in the pressure vessel 2. Reference numeral 7 denotes a seal rubber holder.

The molding powder A inserted and filled in the molding space 8 in the pressure container 2 is obtained by inserting the top punch 11 having the top rubber stopper 10 into the upper part of the pressure container 2 and then, as shown in FIG.
As shown in FIG. 3, the pressure medium seal rubber 5 and the molding rubber mold 4 are pressurized by the pressure medium flowing from the pressure medium inlet / outlet 6 from the high pressure pump (not shown) via the pressure booster (not shown). Via compression molding. After the compression molding is finished, as shown in FIG. 9, the pressure medium is caused to flow out from the pressure medium inlet / outlet 6 to restore the molding rubber die 4, and then the top punch 11 is raised as shown in FIG. At the same time, the bottom punch 9 is lowered to take out the bottomed cylindrical molded body 12 from the pressure container 2.

In the conventional CIP molding as described above, as a method of restoring the molding rubber mold deformed by the pressure during molding, the pressure medium is utilized by utilizing the difference between the pressure of the pressure medium and the atmospheric pressure. The method of letting it flow out naturally was adopted. In other words, due to the pressure medium flowing out, the pressure applied to the molding rubber die becomes smaller than the elastic force of the molding rubber die, and the restoration of the molding rubber die proceeds.

[0006]

However, under natural outflow, when the difference between the pressure of the pressure medium and the atmospheric pressure becomes small due to the progress of outflow, the outflow speed becomes small, and therefore the molding rubber mold is completely restored. It took a long time to complete the molding, which was an obstacle to improving the molding efficiency. As a method of shortening the time required for restoration, it is possible to use a rubber mold for molding with a large elastic force, but in this case, since the rubber mold for molding is rapidly detached from the molded body, it is necessary to release the stress. There is an inconvenience that cracks occur in the molded body. On the other hand, when the filling of the molding powder is started to start the next molding at the time when the restoration is not sufficiently performed, the volume of the molding rubber mold is smaller than that at the time of complete restoration. However, the upper end of the powder in the molding rubber die rises, which hinders the mounting of the top punch, and the powder filling amount must be changed.

[0007]

Means for Solving the Problems The present invention has been made in view of such circumstances, and an object of the present invention is to restore a molding rubber die by decompressing after completion of molding in a short time. It is an object of the present invention to provide a dry hydrostatic pressure molding apparatus and a dry hydrostatic pressure molding method.

That is, according to the present invention, after molding powder is filled in the molding space in the molding rubber mold, the molding is performed by applying hydrostatic pressure from the outer peripheral side of the molding rubber mold with a pressure medium. The following is a dry hydrostatic pressure molding apparatus that restores the molding rubber mold by removing the pressure medium from the outer peripheral side of the molding rubber mold to take out the molded body. Provided is a dry hydrostatic pressure molding apparatus having a compressed air supply means for supplying.

The above-mentioned dry hydrostatic pressure molding apparatus further includes a pressure container for accommodating a molding rubber die, a top punch fitted and fitted in a hole provided in an upper portion of the pressure container,
With a vent for introducing compressed air into the rubber mold for molding, the vent has an opening in the inner wall of the hole of the pressure container, and penetrates the pressure container diagonally above the opening, The top punch has a seal member for closing a gap between the inner peripheral surface of the hole and the outer peripheral surface of the top punch,
By moving the top punch so that the sealing member is located above the vent hole, the molding space is connected to the compressed air supply means via the vent hole in a state where the hole is closed by the top punch. It is preferable that the top punch is moved so that the sealing member is located below the ventilation hole so that the communication between the ventilation hole and the molding space is blocked. Further, it is preferable that the above-mentioned dry hydrostatic pressure molding apparatus has a pressure medium suction means for removing the pressure medium from the pressure medium inlet and / or the pressure medium outlet provided in the pressure container.

Further, according to the present invention, a rubber mold for molding,
With a pressure container to accommodate it, after filling the molding space in the molding rubber mold with molding powder, molding is performed by applying hydrostatic pressure from the outer peripheral side of the molding rubber mold with a pressure medium, A dry hydrostatic pressure molding apparatus for recovering a molding rubber mold by removing a pressure medium from the outer peripheral side of the molding rubber mold to take out a molded body. Alternatively, there is provided a dry hydrostatic pressure molding apparatus having pressure medium suction means for removing the pressure medium from the pressure medium outlet. It is preferable that the above-mentioned dry hydrostatic pressure molding apparatus includes a compressed air supply means for supplying compressed air into the molding rubber die.

Further, according to the present invention, there is provided a dry hydrostatic pressure molding method in which molding is performed using the dry hydrostatic pressure molding apparatus. In the dry hydrostatic pressing method described above, the pressure applied to the molding rubber mold by a pressure medium 5 kgf / cm ² or more, when it is in the range of 40 kgf / cm ² or less, it is preferable to perform the suction removal of the pressure medium . Also, the pressure applied to the molding rubber mold by a pressure medium 5 kgf / cm ² or more, when it is in the range of 40 kgf / cm ² or less, the supply to the molding rubber mold of the compressed air line is preferred.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The CIP molding apparatus of the present invention includes compressed air supply means for supplying compressed air into a molding rubber die. When restoring the molding rubber die by letting out the pressure medium, by introducing compressed air into the molding rubber die, restoration of the molding rubber die and outflow of the pressure medium can be promoted. The time required to restore the mold can be shortened. Further, it is difficult to judge whether or not the restoration of the molding rubber die is completed by the conventional restoration by spontaneous outflow of the pressure medium, but in the present invention, the extent that the molding rubber die swells slightly beyond the restoration. If compressed air is introduced after the compressed air is introduced up to this point, there is also an advantage that such a judgment becomes unnecessary. As the compressed air supply means, for example, a compressor or the like is used. The pressure of compressed air depends on the elastic strength (elastic property) of the rubber mold for molding, but it is 4 kgf /
cm ² or more.

The compressed air is supplied, for example, as shown in FIG. 1, after the pressurization is completed, the pressure medium is allowed to spontaneously flow out from the pressure medium outlet 30 and / or the pressure medium inlet 31 to reduce the pressure,
The top punch 11 is removed, and the compressed air introduction pipe 45 is inserted into the hole portion 13 provided in the pressure vessel 2.

Further, the CIP molding apparatus of the present invention preferably has a vent for supplying compressed air into the molding space. It is preferable that the vent has an opening in an inner wall of a hole provided for fittingly fitting the top punch to the pressure container, and penetrates the pressure container obliquely above the opening.

With such a configuration, the compressed air is supplied in a state where the top punch is moved upward so that the vent hole and the molding space are communicated with each other. Further, the molding is performed in a state where the top punch is moved downward and the communication between the vent hole and the molding space is blocked. Therefore, when supplying compressed air,
The work of removing the top punch and inserting the air introduction pipe can be omitted, and the molding cycle can be shortened.
Further, since the pressure can be reduced with the top punch attached, there is an advantage that impurities can be prevented from being mixed into the molding space.

Further, the above CIP molding apparatus preferably has a seal member on the outer peripheral surface of the top punch. By providing the seal member, the inner peripheral surface of the hole provided in the pressure container and the outer peripheral surface of the top punch can be kept airtight, so that the pressure of the compressed air can be effectively exerted, and the rubber mold The time required for restoration can be further shortened. The sealing member needs to be provided so as to be located above these openings in a state where the vent hole and the molding space are in communication with each other. Further, it is preferable that the seal member is provided over the entire circumference. As the seal member, a hard resin seal ring or the like is preferably used.

FIG. 2 shows an example of a CIP molding apparatus provided with the above-mentioned vent hole and seal member. In the CIP molding apparatus 14 of FIG. 2, a cylindrical molding rubber die 4 is disposed inside the pressure vessel 2, and a top punch 11 and a bottom punch 9 are provided above and below the molding rubber die 4, respectively. Is provided. The molding space 8 is formed by the inner peripheral surface of the molding rubber die 4, the lower end surface of the top punch 11, and the upper surface of the bottom punch 9. On the outer peripheral surface of the molding rubber die 4,
A pressure medium sealing rubber 5 is arranged so as to surround the molding rubber die 4.

The pressure vessel 2 is composed of a main body 2a and a lid portion 2b, and the top punch 11 is fitted and attached in a hole 13 provided in the lid portion 2b. Vent 16 for lid 2b
Which has openings 26, 18 in the upper end surface 24 of the lid 2b and the inner wall of the hole. A seal ring 19 is provided on the outer peripheral surface of the top punch 11 over the entire circumference.

The vent 16 is connected to a compressed air supply means 22 such as a compressor via a high pressure valve 44.

On the other hand, in order to accelerate the restoration of the molding rubber die, it is effective to provide the CIP molding apparatus with a pressure medium suction means for forcibly removing the pressure medium from the outer peripheral side of the molding rubber die. The suction of the pressure medium is performed via a pressure medium inlet and / or a pressure medium outlet provided in the pressure vessel. As the pressure medium suction means, for example, a vacuum pump, an ejector or the like is used.

FIG. 3 shows an example of a CIP molding apparatus provided with the pressure medium suction means. CIP molding apparatus 1 of FIG.
4, the pressure medium tank 32 is connected to the pressure medium inlet 31 via the high pressure pump 33, the pressure booster 34, and the first high pressure valve 35, and the pressure medium outlet 3 via the third high pressure valve 36.
It is connected to 0 and forms a closed loop. Further, a line having the ejector 39 and the second high pressure valve 40 is provided in parallel with the line passing through the third high pressure valve 36.

Furthermore, if the pressure medium suction means is used together with the compressed air supply means, the time required to restore the molding rubber die can be further shortened, which is effective.

FIG. 4 and FIG. 5 show an example of a CIP molding apparatus that uses both pressure medium suction means and compressed air supply means.

The CIP molding device 14 shown in FIG.
The CIP molding apparatus of FIG. 3 and the CIP molding apparatus of FIG. 3 are combined. In addition, the CIP molding device 14 shown in FIG.
Has a configuration in which the CIP molding apparatus of FIG. 2 and the CIP molding apparatus of FIG. 3 are combined.

The supply of compressed air into the molding rubber die and the suction removal of the pressure medium from the outer peripheral side of the molding rubber die reduce the pressure applied to the molding rubber die due to the natural outflow of the pressure medium. cm ² or more, it is preferable to carry out when in the range of 40 kgf / cm ² or less. Otherwise, the molding rubber mold may be rapidly detached from the molded body, and cracks may occur in the molded body due to release of stress.

[0026]

Hereinafter, the present invention will be described in more detail with reference to the illustrated embodiments, but the present invention is not limited to these embodiments.

Using the above CIP molding device, an outer diameter of 4
A bottomed cylindrical molded body having a size of 7.0 mm, an inner diameter of 42.7 mm and a height of 435 mm was produced. This molded body is used as a β-alumina tube for a sodium-sulfur battery.

FIG. 6 shows the configuration of the CIP molding device used for molding. In the CIP molding device 14, a cylindrical molding rubber die 4 and a cylindrical mandrel 3 are arranged inside the pressure vessel 2, and the top punch 11 and the top punch 11 are respectively provided above and below the molding rubber die 4. A bottom punch 9 is provided. Top punch 11 has top rubber stopper 10
Is attached. The molding space 8 is a rubber mold 4 for molding.
Is formed by the inner peripheral surface of the mandrel 3, the peripheral surface of the mandrel 3, the lower end surface of the top rubber plug 10, and the upper surface of the bottom punch 9. A pressure medium sealing rubber 5 is arranged on the outer peripheral surface of the molding rubber die 4 so as to surround the molding rubber die 4. The molding rubber mold 4 and the top rubber plug 10 are made of urethane rubber and have a hardness of 70 ° in Hs (A).

The pressure vessel 2 comprises a main body 2 a and a lid portion 2 b, and the top punch 11 has a hole portion 13 provided in the lid portion 2 b.
It is fittedly fitted inside. Vent 1 for lid 2b
6, which has openings 18 and 26 in the upper end surface 24 of the lid 2b and the inner wall of the hole 13. A seal ring 19 is provided on the outer peripheral surface of the top punch 11 in the circumferential direction. The ventilation port 16 has a high pressure valve 44 and an air dryer 4.
It is connected to the compressor 43 via 2.

The pressure medium tank 32 is connected to the pressure medium inlet 31 via the high pressure pump 33, the pressure booster 34, and the first high pressure valve 35, and is connected to the pressure medium outlet 30 via the fourth high pressure valve 36. And form a closed loop. Further, a line having the pressure reducing control device 37 and the third high pressure valve 38, and a line having the ejector 39 and the second high pressure valve 40 are provided in parallel with the line passing through the fourth high pressure valve 36.

Molding was performed as follows. First, the molding powder was filled into the molding space 8. Top punch 1
The bottom punch 9 having the mandrel 3 attached thereto was attached to the lower portion of the pressure vessel 2 in a state where 1 was removed. A powder metering and feeding device (not shown) was installed above the hole 13, and 420 g of powder weighed in advance was filled into the molding space 8 through the hole 13.

Next, pressure was applied. A state in which the top punch 11 is attached to the hole 13 and the pressure container 2 is housed in a press frame (not shown), and then the pressure medium outlet 30 is closed by the second to fourth high pressure valves 40, 38, 36. Then, the high pressure pump 33
The pressure medium was injected from the pressure medium inlet 31 using the pressure booster 34. Increase the pressure from normal pressure to 2000 kgf / cm ² ,
It was held at 2000 kgf / cm ² for 3 seconds. The press frame includes the top punch 11 and the bottom punch 9
Are used to prevent the protrusion from the pressure vessel 2 due to the molding pressure.

Next, decompression was started to restore the molding rubber mold 4. First, the fourth high-pressure valve 36 is opened closes the pressure medium inlet 31 in the first high-pressure valve 35, by natural outflow of pressure medium, 200 kgf from 2000kgf / cm ² / cm ²
The pressure was reduced to Next, the fourth high pressure valve 36 is closed and the third high pressure valve 38 is opened, and the pressure reducing control device 37 is used to
The pressure was reduced from 0 kgf / cm ² to 20 kgf / cm ² .
The decompression control device 37 is used to control the decompression rate, and operates at a pressure of 350 kgf / cm ² or less. Next, the third high pressure valve 38 was closed and the second high pressure valve 40 was opened, and the ejector 39 started suction of the pressure medium. When the pressure level reaches 0 kgf / cm ² , the pressure vessel 2 is taken out of the press frame, the top punch 11 is moved so that the seal ring 19 is located above the ventilation hole 16, and the molding space 8 is formed through the ventilation hole 16. Compressed air was introduced therein.

Finally, the molded body was taken out. The molded body was taken out by removing the top punch 11 and moving the bottom punch 9 downward 5 seconds after starting the introduction of compressed air. Then, the introduction of compressed air was stopped. The suction of the pressure medium was continued until the top punch 11 was attached to the pressure container 2 after the powder filling in the next cycle.

By performing the molding using the above CIP molding apparatus, the time required for the entire molding cycle could be shortened by about 15 seconds as compared with the conventional case. That is, in the past, since it took a long time to restore the molding rubber die, it was not possible to move to the next molding cycle immediately after taking out the molded body, and the waiting time of about 15 seconds was provided. When it was used, it was not necessary to provide a waiting time, and it was possible to shorten it by 15 seconds. Whether or not the restoration is completed depends on whether the upper end of the molding powder in the molding space contains the pressure container in the press frame when the molding powder of the required weight for molding is filled and the top punch is closed. It was judged whether it was within the range that can be done. That is, when the restoration is insufficient, the volume of the molding space becomes small, and the upper end of the molding powder rises, the top punch does not close sufficiently, and the powder cannot be accommodated in the press frame.

[0036]

According to the present invention, since the CIP molding apparatus has the compressed air supply means or the pressure medium suction means, the rubber mold for molding can be restored in a short time when the pressure is reduced, and the molding efficiency is improved. be able to. Further, by using these together, the restoration time of the rubber mold for molding can be further shortened.

When the compressed air supply means is provided, the ventilation port is further formed by penetrating the pressure vessel and having an opening on the inner wall of the hole provided in the pressure vessel for fittingly mounting the top punch. By providing, when supplying compressed air,
The work of removing the top punch and inserting the air introduction pipe can be omitted, and the molding cycle can be further shortened. Further, by providing a seal member on the outer peripheral surface of the top punch that closes the gap between the inner peripheral surface of the hole and the outer peripheral surface of the top punch, the inner peripheral surface of the hole provided in the pressure vessel and the outer periphery of the top punch are provided. Since the surfaces can be kept airtight, the pressure of the compressed air can be effectively exerted, and the time required to restore the molding rubber die can be further shortened.

[Brief description of the drawings]

FIG. 1 is a cross-sectional explanatory view showing an example of a CIP molding apparatus of the present invention.

FIG. 2 is a cross-sectional explanatory view showing another example of the CIP molding apparatus of the present invention.

FIG. 3 is a cross-sectional explanatory view showing still another example of the CIP molding apparatus of the present invention.

FIG. 4 is a cross-sectional explanatory view showing still another example of the CIP molding apparatus of the present invention.

FIG. 5 is a cross sectional explanatory view showing still another example of the CIP molding apparatus of the present invention.

FIG. 6 is a cross sectional explanatory view showing still another example of the CIP molding apparatus of the present invention.

FIG. 7 is an explanatory sectional view showing a powder filling step of a conventional CIP molding method.

FIG. 8 is a cross-sectional explanatory view showing a pressing step of a conventional CIP molding method.

FIG. 9 is a cross-sectional explanatory view showing a pressure reducing step of a conventional CIP molding method.

FIG. 10 is a cross-sectional explanatory view showing a molded body removing step of a conventional CIP molding method.

[Explanation of symbols]

1 ... powder feeding nozzle, 2 ... pressure vessel, 3 ... mandrel,
4 ... molding rubber mold, 5 ... pressure medium sealing rubber, 6 ... pressure medium inlet / outlet, 7 ... seal rubber holder, 8 ... molding space, 9
... Bottom punch, 10 ... Top rubber plug, 11 ... Top punch, 12 ... Molded body, 13 ... Hole portion of pressure vessel lid, 14 ... CIP molding device, 16 ... ..Vents, 18 ...
Vent opening, 19 ... Seal ring, 22 ... Compressed air supply means, 23 ... Suction means, 24 ... Upper end surface of lid,
26 ... Vent opening, 29 ... Powder metering and feeding device, 3
0 ... Pressure medium outlet, 31 ... Pressure medium inlet, 32 ... Pressure medium tank, 33 ... High pressure pump, 34 ... Intensifier, 35 ... First
High pressure valve, 36 ... Fourth high pressure valve, 37 ... Decompression control device, 3
8 ... Third high pressure valve, 39 ... Ejector, 40 ... Second
High pressure valve, 42 ... Air dryer, 43 ... Compressor, 44 ... High pressure valve, 45 ... Compressed air introduction pipe, 46 ...
・ Lid, 47 ... Pressure gauge.

Claims (8)

[Claims] 1. Molding is performed by filling molding space in a molding rubber mold with molding powder, and then applying hydrostatic pressure from the outer peripheral side of the molding rubber mold with a pressure medium, and subsequently molding the molding. A dry hydrostatic pressure molding apparatus that restores the molding rubber mold by removing the pressure medium from the outer peripheral side of the molding rubber mold and takes out the molded body, and supplies compressed air into the molding rubber mold. A dry hydrostatic pressure molding apparatus comprising a compressed air supply means. 2. A molding rubber mold and a pressure container for accommodating the molding rubber mold. The molding space in the molding rubber mold is filled with molding powder, and the pressure medium is supplied from the outer peripheral side of the molding rubber mold. Molding is carried out by applying hydrostatic pressure to the molded rubber mold, and then the pressure medium is removed from the outer peripheral side of the molding rubber mold to restore the molding rubber mold and take out the molded body. A dry hydrostatic pressure molding apparatus comprising a pressure medium suction means for removing a pressure medium from a pressure medium inlet and / or a pressure medium outlet provided in the pressure vessel. 3. The dry hydrostatic pressure molding apparatus according to claim 2, further comprising compressed air supply means for supplying compressed air into the molding rubber mold. 4. A pressure vessel for accommodating the molding rubber die, a top punch fitted in a hole provided in an upper portion of the pressure vessel in a fitting manner, and introducing compressed air into the molding rubber die. The vent hole has an opening in the inner wall of the hole of the pressure container, and penetrates the pressure container diagonally above the opening, and the top punch is the hole. Has a sealing member that closes the gap between the inner peripheral surface of the top punch and the outer peripheral surface of the top punch, and moves the top punch so that the sealing member is located above the vent hole, and thereby the hole portion. Is closed by the top punch, the molding space is communicated with the compressed air supply means through the ventilation hole, and the top punch is moved so that the sealing member is located below the ventilation hole. The dry hydrostatic pressure molding apparatus according to claim 1, wherein the communication between the vent hole and the molding space is interrupted by the setting. 5. The dry hydrostatic pressure molding apparatus according to claim 4, further comprising pressure medium suction means for removing the pressure medium from a pressure medium inlet and / or a pressure medium outlet provided in the pressure vessel. 6. A dry hydrostatic pressure molding method, wherein molding is performed using the dry hydrostatic pressure molding apparatus according to any one of claims 1 to 5. 7. A pressure applied to the molding rubber mold by a pressure medium 5 kgf / cm ² or more, when it is in the range of 40 kgf / cm ² or less, the dry isostatic according to claim 6 for sucking and removing the pressure medium Press forming method. 8. A pressure applied to the molding rubber mold by a pressure medium 5 kgf / cm ² or more, when it is in the range of 40 kgf / cm ² or less, 6 also claim to supply into the molding rubber mold of the compressed air 7. The dry hydrostatic pressure molding method according to 7.