JPS61182900A - Compression forming device of granular body and its formation - Google Patents

Abstract

PURPOSE:To obtain a formed body made uniform in density distribution by forming granular bodies packed in a square hollow part by providing the granular bodies with equidisplacement compressing from four sides at the same time with the aids of pressure blocks. CONSTITUTION:A box-shaped granular-body housing part blocked by a lower blocking body 8 is formed at the lower end-surface of a square hollow part 6 formed with four pressure-blocking pieces 5 by raising a lower ram 9. Next, the granular-body housing part is blocked by an upper blocking body 1 after charging the granular bodies into the housing part. Next, the four pieces 5 and advanced along the sides of a square hollow hole 3a in the arrow directions by actuating hydraulic cylinders 7 to reduce the volume of hollow part 6 in order to obtain a formed body by compressing the granular bodies into the desired outside dimensions. Thereafter, the pressure blocks 5 are retreated by raising the blocking body 1 and actuating the hydraulic cylinders 7 reversely. Then, the formed body is discharged from the hollow part 6 by lowering the body 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a compression molding apparatus for powder and granular materials and a method thereof, and particularly relates to a compression molding apparatus and molding method for powder and granular materials for obtaining a compact having a uniform density. .

[Conventional technology]

Conventionally, compression molding of granular materials has been carried out using a compression molding apparatus using an upper punch, a lower punch, and a die. The operating state of the molding section of this compression molding apparatus will be explained in the order of steps with reference to cross-sectional views of FIGS. 4(a) to 4(d). First, a required amount of powder A is filled from the upper opening into the powder storage section formed by the center hole 10a of the die 10 and the upper end surface 11a of the lower bunch 11 that fits into the center hole 10a and the center hole 10a. do(
Figure 4-)). Next, the upper punch 12 descends and fits into the center hole 10a of the die from above, compressing the granular material A from above (FIG. 4(b)). Next, the lower punch 11 is raised to compress the granular material A from the lower surface to a desired external dimension to form a molded object B (FIG. 4(C)).

Next, the upper bunch 12 is raised and the tip of the upper punch 12 is pulled up and extracted from the center hole 1 (la) of the die IO.Next, with a slightly delayed operation, the lower punch 11 in the center hole 10a is raised. The molded body B is discharged from the die 10 (Fig. 4(d)).Then, the lower bunch 11 is discharged from the die 10 as shown in Fig. 4(a).
) to end the compression molding operation of the powder and granular material.

[Problem that the invention seeks to solve]

The powder molding apparatus and the molding method thereof constructed by performing such a series of operations have the following drawbacks.

(a) Compression molding is performed from two directions, namely compression from the upper surface by the upper punch 12 and compression from the lower surface by the lower punch 11, but the density distribution of the compact B in the compression molding direction is Body B had a high density near the top and bottom, and a low density in the center, making it impossible to obtain a molded body with a uniform density distribution. In order to overcome these drawbacks, compression molding apparatuses using compression molding methods such as the isostatic method have been developed, but they also have the drawback of not being suitable for mass production.

←) Also, when discharging the molded body B from the center hole 10a of the die 10, the side surface of the molded body B and the center hole 10 of the die lO
Friction marks are generated on the side surface of the molded body B due to friction with the side wall of the molded body B.

[Means for solving problems]

An object of the present invention is to provide a compression molding apparatus for powder and granular materials and a molding method thereof, which eliminates such conventional disadvantages.

The apparatus for compression molding powder and granular material and the molding method thereof according to the present invention are arranged so that the compression molding apparatus and the molding method for powder and granular materials contact each of the four sides of the square hollow hole of the frame body, engage with each other, and move back and forth along each side, and form a square hollow hole in the center of the frame body. It is characterized by having four pressurizing block pieces forming a rectangular hollow part, and a closing part consisting of a pair of upper and lower movable plate bodies that temporarily close the openings on the upper and lower surfaces of the rectangular hollow part.

〔Example〕

Hereinafter, the present invention will be explained with reference to the drawings.

1 and 2 are a longitudinal sectional view and a plan view, respectively, of a molding section of a compression molding apparatus according to an embodiment of the present invention.

In the figure, reference numeral 1 denotes a flat upper blocker that closes the upper part of the rectangular hollow part 6, and is connected in a suspended state to an upper ram 2 disposed in a frame 4 at the upper center of the compression molding apparatus. Drooping. At the bottom of the upper closure body 1 is a square hollow hole 3 in the center.
A frame body 3 having a shape a is supported and fixed to a pedestal 4. The hollow hole 3a of this frame 3 has a cross section obtained by cutting one non-right angle of a right-angled isosceles triangle, which is obtained by dividing the square hollow hole 3a into four equal parts by two diagonal lines, at a point within half of the opposite side of the right angle. Four pressurizing block pieces 5 each having a shape are housed in a square hollow hole 3a with their perpendicular opposite sides in close contact with each other so as to be slidable along the sides. is forming. 7, the tip 7a is placed outside the frame 3.
One or more hydraulic cylinders are supported and fixed by penetrating the frame 3 from the 11th side, and the working end 7b is a pressurizing cylinder.

It is connected to one or a several pieces of the strip 5. Reference numeral 8 denotes a flat plate-shaped lower closing body for closing the lower part of the rectangular hollow portion 6, and is connected and fixed in an upright state to lower rams arranged on four frames at the lower part of the frame body 3.

Next, FIG. 1 shows the operating state of the molding section of the apparatus of the present invention.

The steps will be explained in order with reference to FIG. 2 and FIGS. 3(a) to 3(d).

First, raise the lower ram 9 and remove the four pressure block pieces 5.
The lower closing body 8 is brought into close contact with the lower end surface of the rectangular hollow part 6 previously formed in the center of the frame 3 to close it,
A box-shaped powder storage section is formed (FIG. 3(a)). Next, the powder and granules are injected and filled into the powder and granule container from the upper opening using a known powder filling mechanism (not shown), and then the upper ram 2 is lowered to fill the upper end surface of the rectangular hollow part 6 with the upper ram 2. The upper part is closed by bringing the closing body 1 into close contact with each other (FIG. 3(b)). Next, operate the hydraulic cylinder 7 to pressurize the four units.

The pressure block piece 5 is moved forward along the side of the square hollow hole 3a in the direction of the arrow (Fig. 2), and the pressurizing block piece 5 to which the operating end 7b of the hydraulic cylinder 7 is not connected is also linked to form a square shape. The volume of the rectangular hollow part 6 is gradually reduced by moving along the sides of the hollow hole 3a, and the powder and granular material A is compressed to a desired external dimension to form a molded body B (third Diagram (C)
). Thereafter, the upper closing body 1 is raised to open the upper surface of the rectangular hollow portion 6, and then the hydraulic cylinder is operated in the opposite direction to move the pressurizing block piece 5 backward in the direction opposite to the arrow (FIG. 2). Next, in a slightly delayed operation, the lower closing body 8 is lowered to open the lower surface of the rectangular hollow part 6, and the molded body B is also discharged from the rectangular hollow part 6, thereby completing a series of steps of compression molding operation of the granular material. (Fig. 3(d)).

〔Effect of the invention〕

As described above, the present invention has the following effects.

The powder and granules filled in the middle rectangular hollow part are compressed with equal displacement simultaneously from all four directions toward the center by the pressurizing block pieces, so that a molded product with a uniform density distribution can be obtained. .

(il) When the molded body is discharged from the square hollow part, the molded body does not come into contact with the side wall of the square hollow part, so the molded body has the advantage that no friction occurs.

[Brief explanation of drawings]

1 and 2 are a longitudinal cross-sectional view and a plan view, respectively, of a molding section of a compression molding apparatus of the present invention. FIG. 6 is a cross-sectional view showing the operating state of the molding section of the second compression molding device in the order of steps. 1: Upper blocker, 2: Upper ram, 3: Frame, 3a: Hollow hole, 4: Frame, 5: Pressure block piece, 6: Square hollow part,
7 two hydraulic actuation cylinders, 7a: tip, 7b: working end, 8: lower blocker, 9: lower ram, lO: die, 1
0a: Hole, 11: Lower punch, 11a: Upper end surface, 12: Upper punch, A: Powder, B: Molded body. 8 z diagram ((2)
(b) Figure 3 ′ 〒-I2 ((1) tb) (C)
and Zuno@, 4z

Claims (2)

[Claims] (1) four pressurizing block pieces that closely fit and engage each of the four sides of the square hollow hole of the frame and move back and forth along each side to form a square hollow in the center of the frame; A compression molding apparatus for powder and granular material, characterized in that the device has a closing section consisting of a pair of upper and lower movable platens that temporarily closes openings on the upper and lower surfaces of the rectangular hollow section. (2) closing the lower surface of the square hollow part formed by the four pressurizing block pieces in the center of the square hollow hole of the frame body with a movable platen body to form a powder storage part; Filling the granular material storage section with powder and granules, and after closing the upper surface of the rectangular hollow section with a movable platen, moving the four pressurizing block pieces in conjunction to reduce the volume of the rectangular hollow section. A method for compression molding a powder or granular material, the method comprising the step of compression molding the powder or granule.