JPH05156311A - Method and device for dry isotropic pressing - Google Patents

Abstract

PURPOSE:To provide a dry isotropic pressing device with the compacting reactive force held by a die (container) itself. CONSTITUTION:This device is provided with a die cavity 10 to be filled with a material 8 to be treated, a container 9 capable of supporting the compacting reactive force, lids 2 and 3 pierced with the holes 11 and 12 for supporting the end of the inserted container 9 and through which the container 9 is freely passed with the material 8 confronted with a rubber forming die 6 and a conveyor 13 for moving the container 9 filled with the material 8 in the cavity 10 outside the pressure vessel 1 into and out of the rubber forming die 6 of a rubber die 7 through the holes 11 and 12.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a dry isotropic molding method and apparatus.

[0002]

2. Description of the Related Art A liquid such as water is used as a pressure medium and is usually 1000
The technology of molding by applying a high isotropic pressure of kgf / cm ² or more to an object to be treated such as powder is the cold isostatic pressing method (hereinafter referred to as CI
Of these CIPs, the dry method (dry back method) of pressurizing with isotropic pressure of a hydraulic medium through a rubber mold previously incorporated in a pressure vessel is known as a so-called rubber press. There is.

As one of the rubber presses, Japanese Patent Publication Sho
There is a technique disclosed in Japanese Patent Laid-Open No. 45-41355, in which a pair of rubber molds having a mold cavity on a mating surface are provided in a molded rubber mold in a pressure vessel by a pair of push rods so that the rubber molds can be freely inserted and removed.

[0004]

In the technique disclosed in the above publication, since the mold cavity for the object to be processed is formed by the abutting surfaces of the pair of rubber molds, the molding reaction force during molding is reduced. Since it acts on the push rod via the rubber mold, a separate device for supporting this molding reaction force was required. Also, since there is only one mold cavity defined by a pair of rubber molds,
Only one molded product could be obtained in one molding process, which was very inefficient.

Further, since the pair of rubber molds defining the mold cavity are elastically deformed and cannot support the molding reaction force, there is a risk of inducing cracks in obtaining a thin molded product. Therefore, an object of the present invention is to solve the above-mentioned problems by allowing the molding reaction force to be received by the housing itself of the object having the mold cavity.

[0006]

According to the present invention, a rubber mold 7 composed of a pressure rubber mold 5 and a molding rubber mold 6 is incorporated into a pressure vessel 1 having lids 2 and 3 capable of carrying an axial force. In order to achieve the above-mentioned object in a dry isotropic molding method in which an object 8 to be processed is pressure-treated with a hydraulic medium isotropically through a mold 7,
The following technical measures are taken.

That is, according to the first aspect of the present invention, the mold cavity 10 of the container 9 having the mold cavity 10 for filling the object 8 to be processed and capable of supporting the molding reaction force,
After filling the object to be treated 8 outside the pressure vessel 1, the rubber mold 7
In the molding rubber mold 6 at
The container 9 filled in 10 was inserted by inserting the lids 2 and 3 through the lids 2 and 3 so that the object to be treated 8 came into contact with the molded rubber mold 6 and moving in the axial direction of the container.
After that, isotropic pressure is applied to the pressure rubber mold 5 in the rubber mold 7 to subject the object 8 in the mold cavity 10 to pressure treatment.

The present invention also has lids 2 and 3 capable of bearing axial force.
A pressure vessel 1 having a pressure rubber die 5 and a rubber die 7 composed of a pressure rubber die 5 and a molding rubber die 6 and incorporated in the pressure vessel 1. In order to achieve the above-mentioned object, the following technical means is taken in a dry type isotropic pressure molding apparatus for performing pressure treatment with isotropic pressure by a hydraulic medium.

That is, the present invention according to claim 2 has the mold cavity 10 for filling the object to be processed 8 and the container 9 capable of supporting the molding reaction force. The container 9 can be inserted and removed in the axial direction of the container while being in contact with the molded rubber mold 6, and the support holes 11 and 12 for supporting the end of the inserted container 9 are provided through the lids 2 and 3. Equipped with a pressure vessel
1 Container 9 with mold cavity 10 filled with material 8 to be processed outside
It is characterized in that it is provided with a conveying means 13 for inserting / removing into / from the molding rubber die 6 of the rubber die 7 through the support holes 11 and 12.

Furthermore, the present invention according to claim 3 provides the invention according to claim 2.
An elastically deformable ring body 14 is fitted to the mold surface of the mold cavity 10 in the container 9. Further, the present invention according to claim 4 is characterized by including a partition member 15 for partitioning the mold cavity 10 in the container 9 of claim 2 in the insertion direction of the container 9 and in the axial direction of the container. Is.

Further, the present invention according to claim 5 provides the invention according to claim 3.
The ring member 14 and the partition member 15 of claim 4 are provided.

[0012]

According to the present invention, powder such as ceramics or other object to be processed is placed inside the mold cavity 10 outside the pressure vessel 1.
The object 9 to be processed is inserted into the molding rubber mold 6 of the rubber mold 7 through the container 9 filled with 8 and filled with the object 8 to be processed by the transporting means 13 through the movement in the axial direction of the container.

After that, by applying an isotropic pressure by a hydraulic medium to the pressure rubber mold 5 in the rubber mold 7, the object to be processed is
Although 8 is pressure-treated, the container 9 itself bears the molding reaction force. When the predetermined pressurizing process is completed, the container 9 in which the molded processed body is stored is pulled out from the pressure vessel 1 via the carrying means 13.

In the above description, the molding reaction force during molding is the container
Since the mold cavities 10 are provided by a plurality of mold cavities 10, the production efficiency can be improved. Further, by fitting the elastic ring body 14 in the mold cavity 10, even if the outer diameter of the molded body is increased by springback after depressurization, the amount of springback is compensated by the reduction of the ring body 14 to form the molded body. Makes it easy to remove the body.

Further, by providing the mold cavity 10 with the partition member 15, the thin molded body can be molded without causing cracking.

[0016]

Embodiments of the present invention will be described in detail below with reference to the drawings. In FIGS. 1 to 3 showing the first embodiment, a cylindrical pressure vessel 1 has its vessel axis centered horizontally. The pressure vessel 1 is supported by a frame or the like (not shown), and lids 2 and 3 are fitted to both open ends of the pressure vessel 1 via seals or the like (not shown).

Axial force acts on the lids 2 and 3 during molding,
In the illustrated example, this axial force is a rectangular frame-shaped press frame 4 that can be engaged and disengaged at a position radially off the container axis.
It is possible to carry by providing. However, the axial force carrying action may be carried out by screwing the lids 2 and 3 onto the open end of the container as shown in FIG.

In the pressure vessel 1, a rubber mold 7 consisting of a pressure rubber mold 5 and a molding rubber mold 6 inserted therein is incorporated. In the molding rubber mold 6 of the rubber mold 7, Container (mold) 9 for powder such as ceramics and other objects to be treated 9
Fitting hole 7A that can be inserted and removed via movement in the container axial direction
Is formed. The container 9 has a flat plate shape with a rectangular cross section, and is formed with three mold cavities 10 each having a plane circular shape in the figure. The mold cavity 10 can be filled with an object 8 to be treated outside the pressure vessel 1. ing.

As shown in FIG. 3, the housing 9 has a molding isotropic pressure P.
Although the molding reaction force P1 can be carried by the container 9 itself, the container 9 is inserted into and removed from the rubber mold 7, and the lids 2, 3
In order to support both ends by the support, support holes 11 and 12 having a rectangular cross section are formed around the container axes of the lids 2 and 3. A transfer means 13 is provided outside the pressure vessel 1, and in this embodiment, the transfer means 13 is provided with a charging 13A and a withdrawing 13B that are distributed, and the object 8 to be treated is placed outside the pressure vessel 1. Filled container 9
Can be loaded and unloaded via movement in the axial direction of the container.

The conveying means 13 may be of any type such as a belt conveyor or a dolly, and it may be one for both loading and withdrawing. Next, the operation of the first embodiment will be described. The object to be treated 8 is filled in the mold cavity 10 of the container 9 outside the pressure vessel 1. Even if this charging is performed on the charging 13A of the conveying means 13, the charging is performed at a place other than this.
It may be placed on 13A, and in any case, it is advantageous to fill with a thin sheet material as an underlay.

The container 9 filled with the object to be treated 8 is a conveying means.
It is inserted through the support hole 11 of the lid 2 via 13, and one end is supported by the support hole 11 and the insertion end is supported by the support hole 12. After that, by applying an isotropic pressure by the hydraulic medium to the pressure rubber mold 5, the mold cavity 10 is subjected to the isotropic pressure P through the molding rubber mold 6.
The object 8 to be treated therein is pressure-treated, and the molding reaction force P1 is carried by the container 9 itself.

When the predetermined pressurizing process is completed, the container 9 is drawn out of the pressure vessel 1 via the carrying means 13 after depressurization, and the molded process body is taken out from the mold cavity 10. 4 to 6 show a second embodiment, in which a ring member 14 made of elastically deformable rubber or the like is fitted to the mold surface of the mold cavity 10 and a partition member 15 is provided.

Here, the ring body 14 compensates the amount of spring back of the molded body after depressurization by reducing the ring body 14 to facilitate removal from the mold cavity 10, and at the same time, the ring body 14 By setting the inner / outer diameter ratio to 1.05 or less, the displacement in the tangential direction is small and cracking of the molded body does not occur. Specifically, in FIG. 5, D ₀
Is the outer diameter of the mold cavity 10, D is the inner diameter of the ring body 14, and D ₁
Is the outer diameter of the treated body after molding, H is the height before molding, H ₁ is the height after molding, and the outer diameter D ₁ is the springback amount (ratio) after depressurizing the molded body, and D> It must be D ₁ (1-α).

Assuming that the ring body 14 is not shrunk, a target object having a volume shrinkage ratio β is formed in the mold cavity 10 having an outer diameter D and a height H, and the outer diameter D ₁ and the height H ₁ are obtained. β × D ² × H = D ₁ ² × H ₁ = (D × (1-α)) ² × H ₁ ≈
It becomes D ² (1-2 α) H ₁ . However, since α = 1% or less, (1-α) ² = 1−
2α On the other hand, (D ₀ ² −D ² ) × H = (D ₀ ² −D ₁ ² ) H ₁ = {D ₀ ² −D
² (1-2α)} H _{1 From} the relational expression above, if D ₀ / D = K, then K ² = (1-β) / (1-β / 1-2α).

For example, when the ceramic powder is compressed, since α≈0.01 β = 0.6, K = 1.016. On the other hand, empirically, if it is about 5% or less, it is considered that K = 1.04 to 1.02, because even if the rubber mold shrinks in the tangential direction of the molded product, it does not affect cracking. Further, in order to improve the molding shape and to swing the ring body 14 toward the inner diameter side, a recess 16 is formed in the peripheral portion of the mold cavity 10 of the container 9.

Except for the above points, parts common to the first embodiment described with reference to FIGS. 7 to 14 show a third embodiment, which is provided with a plate-like partition member 15 for partitioning the mold cavity 10 into two stages in the vertical direction with respect to the insertion direction of the container 9 and the axial direction of the container. Thereby, two-stage molding can be performed, and since the partition member 15 serves as a so-called mold surface, a molded body with high dimensional accuracy can be obtained.

The partition member 15 may be fixedly mounted in the molded rubber mold 6 as shown in the drawing, or may be mounted on the container 9 itself, and the mold cavity partitioned by the partition member 15 into upper and lower parts. The upper and lower parts 10 may have the same shape or different shapes. Since the other points are common to the above-described embodiment, common parts are indicated by common symbols.

In each of the above embodiments, the mold cavity 10 may have a tooth shape as shown in FIG. 16, and as shown in FIG. 17, it has a so-called core mold 10A to obtain a ring-shaped molded body. The shape may be arbitrary.

[0029]

The present invention is as described above, and according to the method of the present invention according to claim 1, the molding reaction force is received by the container, and the pressing direction acts in the direction perpendicular to the molding under the same conditions. Therefore, the difference between the cracked portions is eliminated, and a molded product with good dimensional accuracy can be obtained. According to the device of the present invention according to claim 2, since the molding reaction force is carried by the container itself, a reaction force supporting device for receiving the reaction force is not required, and the pressure processing device has a simple structure and is inexpensive. Can be provided.

Further, in the device of the present invention according to claim 3, by fitting the elastically deformable ring body in the mold cavity,
The molded body can be easily taken out, and the springback amount of the molded body can be compensated to reliably prevent cracking. Also,
In the device of the present invention according to claim 4, it is possible to mass-produce thin compacts by the interposition of the partitioning member and to perform good die finishing. Can have both.

[Brief description of drawings]

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

FIG. 2 is a vertical sectional side view of FIG.

FIG. 3 is a plan view showing the molding behavior of the first embodiment.

FIG. 4 is an overall vertical sectional view showing a second embodiment of the present invention.

5 is an enlarged vertical side view of FIG.

FIG. 6 is a plan view of a container (mold) of a second embodiment.

FIG. 7 is a vertical sectional view showing a third embodiment of the present invention before charging.

FIG. 8 is a vertical sectional side view of FIG.

FIG. 9 is a vertical sectional view of the third embodiment after charging.

10 is a vertical sectional side view of FIG.

11 is a cross-sectional plan view of FIG.

FIG. 12 is a vertical sectional view of the third embodiment during molding.

13 is a vertical sectional side view of FIG.

FIG. 14 is a vertical sectional view of the third embodiment when it is pulled out.

FIG. 15 is a vertical sectional view showing the whole of the fourth embodiment.

FIG. 16 is a plan view showing a second embodiment of the container.

FIG. 17 is a plan view showing a third embodiment of the container.

[Explanation of symbols]

 1 Pressure Vessel 2 Lid 3 Lid 5 Pressure Rubber Mold 6 Molding Rubber Mold 7 Rubber Mold 9 Container 10 Mold Cavity 13 Conveying Means

Claims (5)

[Claims] 1. A rubber mold (7) comprising a pressure rubber mold (5) and a molding rubber mold (6) is incorporated in a pressure vessel (1) having a lid (2) (3) capable of bearing axial force. , The object to be processed through the rubber mold (7)
In a dry isotropic molding method in which (8) is pressure-treated with an isotropic pressure of a hydraulic medium, a mold cavity (1
0) and capable of supporting the molding reaction force
In the mold cavity (10) of (9), place the object to be processed outside the pressure vessel (1).
Molded rubber mold in the rubber mold (7) after filling with (8)
Inside the (6), the container (9) in which the mold cavity (10) is filled with the object to be processed (8) is covered by the lid (2) (3) so that the object to be processed (8) may contact the molded rubber mold (6). ) Is inserted by moving in the axial direction of the container, and then isotropic pressure is applied to the pressure rubber mold (5) in the rubber mold (7) to dispose the object (8) in the mold cavity (10). A dry isotropic molding method characterized by pressure treatment. 2. A pressure vessel (1) having a lid (2) (3) capable of bearing an axial force, a pressure rubber mold (5) and a molding rubber mold (6). With a rubber mold (7) incorporated in
Object to be treated (8) in the molding rubber mold (6) in the rubber mold (7)
A mold cavity (10) for filling an object to be processed (8) in a dry isotropic molding machine that pressurizes an object with an isotropic pressure by a hydraulic medium.
And a container capable of supporting the molding reaction force
(9), the container (9) can be inserted and removed in the axial direction of the container with the object (8) in contact with the molded rubber mold (6), and the end of the inserted container (9). Cover the support holes (11) (12)
(2) A container (9) which is provided by penetrating through (3) and has a mold cavity (10) filled with an object (8) to be treated outside the pressure vessel (1) is provided with the support hole (11) ( A dry isotropic molding apparatus comprising a conveying means (13) which is inserted into and removed from a molding rubber mold (6) of a rubber mold (7) via a (12). 3. A dry isotropic molding, characterized in that an elastically deformable ring body (14) is fitted to the mold surface of the mold cavity (10) of the housing body (9) of claim 2. apparatus. 4. A partition member (15) for partitioning the mold cavity (10) in the container (9) according to claim 2 in the insertion direction of the container (9) and in the axial direction of the container. Dry type isotropic molding machine. 5. A dry isotropic molding apparatus comprising the ring body (14) according to claim 3 and the partition member (15) according to claim 4.