JPH06240301A - Method and device for filling powder in compacting powder - Google Patents

Abstract

PURPOSE:To fill a powder in a die without forming a bridge in the production of sintered parts. CONSTITUTION:A powder 4 is dropped into a die 1, and a lid member 6 is fixed with ifs hole 6a positioned directly above a core 2. The core 2 is then raised until its upper end face is flush with the upper end face of the die 1, hence the powder 4 on the core 2 is extruded from the hole 6a, and the cavity enclosed by the die 1, core 2 and lower punch 3 is filled with the powder 4. The powder on the upper end faces of the lid member 6 and die 1 is removed, and the powder 4 is compacted by the upper punch 5 and lower punch 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder filling method and apparatus for powder molding in the manufacturing process of sintered parts, and more particularly to a powder filling method and apparatus suitable for manufacturing ring-shaped parts.

[0002]

2. Description of the Related Art In the process of manufacturing a sintered part, powder is filled in a die and pressure-molded. When press-molding a ring-shaped part, the outer periphery is partitioned by the die, the bottom is partitioned by the lower punch, and the inner periphery is partitioned by the core. Molded.

When molding such a ring-shaped component, the powder was filled by dropping it between the core and the die as shown in Japanese Utility Model Laid-Open No. 62-101697.

[0004]

When the die is filled with the powder by the above-mentioned method when forming a thin ring-shaped part, a bridge may be formed due to a narrow gap between the core and the die. A component that is formed by compression-molding powder and sintering it in a state where bridges are formed and voids are defective.

Even in the case of a relatively thick ring-shaped part, in the case of a magnetic field press for applying a magnetic field during powder compression in order to manufacture an anisotropic magnetic material, a die, a core, etc. form a magnetic path. It is made of magnetic material, and these have residual magnetism, and powder of magnetic material is adsorbed to form a bridge easily.

The present invention has been made to solve the above problems, and an object thereof is to form a powder without forming a bridge when molding a thin ring-shaped component or an anisotropic magnetic material ring-shaped component. The purpose is to provide a means for filling the body.

[0007]

The powder filling method in powder molding according to the present invention is performed by dropping powder into a space where an outer peripheral surface is formed by a die and a bottom is formed by a lower punch and a core. With the lid member having a hole having the same shape as the above, the core is lifted in the state where the lid member is brought into close contact with the upper end surface of the die at a position directly above the core, the outer peripheral surface is formed by the die, and the bottom is punched by the bottom punch. The powder is filled in a ring-shaped space where the inner peripheral surface is formed by the core.

Further, the powder filling apparatus for powder molding of the present invention fills the powder in a ring-shaped space where the outer peripheral surface is formed by the die, the bottom is formed by the lower punch, and the inner peripheral surface is formed by the core. In the powder filling device for filling, a lid member having a hole having the same shape as the outer periphery of the core is separated from the opening of the void and a position where the hole covers the opening of the void and is located directly above the core. Between the upper end surface of the die and the upper end surface of the die when the hole of the lid member is directly above the core. It is configured so that it can rise to a certain position.

[0009]

According to the powder filling method in the powder molding of the present invention, the core is lowered when the powder is dropped into the die, and the powder accumulated in the die is not supported by the core and a void is generated. Hateful.

When the core rises so as to form the inner peripheral surface of the ring-shaped part, the lid member is on the powder, and the hole of the lid member located right above the core has the same shape as the outer periphery of the core. Therefore, only the powder right above the core is discharged out of the die.

In this way, the ring-shaped void having the outer peripheral surface formed by the die, the bottom formed by the lower punch, and the inner peripheral surface formed by the core is filled with the powder without voids.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are sectional views showing a powder filling device in powder molding which is a first embodiment of the present invention. Reference numeral 1 shown in the drawing is a die for press-molding the powder 4 in the manufacturing process of the sintered part, and is supported by a die holder of a press (not shown).

Reference numeral 3 denotes a ring-shaped lower punch, a part of the outer peripheral surface of which is fitted in the hole 1a of the die 1. Reference numeral 2 denotes a core, which is vertically moved by an air cylinder (not shown) while being fitted in the inner peripheral surface of the lower punch.

The lid member 6 is a hole 6 having the same shape as the outer peripheral surface of the core 2.
a, and the hole 6a can be attached to the upper end surface of the die 1 with the hole 6a positioned right above the core 2. The material of the lid member 6 may be a member such as a resin or a metal plate whose dimensional shape does not change, but a member that is resistant to rust is desirable, and in the case of a magnetic field press, a non-magnetic material is used.
Reference numeral 5 is an upper punch attached to the working rod of the press.

In the above structure, first, the powder 4 is dropped into the hole 1a of the die 1 with the core 2 lowered and the lid member 6 removed as shown in FIG. Next, as shown in FIG. 2, the lid member 6 is positioned and attached at a position where the hole 6a is directly above the core 2.

Next, as shown in FIG. 3, when the upper end surface of the core 2 is raised to the position where the upper end surface of the core 2 is at the height of the upper end surface of the die 1, the powder 4 on the upper portion of the core 2 is extruded from the hole 6a. Then, the powder 4 is filled in the space surrounded by the die 1, the core 2 and the lower punch 3. Next, as shown in FIG. 4, after the powder above the upper end surface of the lid member 6 and the die 1 is removed, the powder 4 is compressed by the upper punch 5 and the lower punch 3.

FIG. 5 shows a powder filling apparatus for powder molding which is a second embodiment of the present invention. In this example, powder 4
Is automatically filled. The powder box 7 is horizontally driven by the cylinder rod 9 with the opening of the powder box 7 turned down to the upper end surface of the die 1. The powder 4 is supplied by the bellows hose 8 attached to the powder box 7.

The lid member 6 is fixed to the powder box 7. The die 1, the core 2, the lower punch 3 and the upper punch 5 are constructed in the same manner as in the first embodiment. The powder 4 is dropped by moving the powder box 7 so that the illustrated shaking stroke range of the powder box 7 moves over the hole of the die 1.

Thereafter, the powder box 7 is stopped at the position where the hole of the lid member is directly above the core 2 as shown in the figure, and the core 2 is raised. Similar to the first embodiment, the powder 4 on the upper portion of the core 2
Is extruded from the hole 6a, and the powder 4 is filled in the space surrounded by the die 1, the core 2 and the lower punch 3.

Next, the powder box 7 is retracted from the moving path of the upper punch 5 to compress the powder 4 by the upper punch 5 and the lower punch 3 in a state where the powder above the core 2 is removed. Is done.

[0021]

As described above, according to the powder filling method of the present invention, even when a thin ring-shaped part is formed in the process of manufacturing a sintered part, the powder is diced without forming a bridge. Can be filled inside.

Also, when the powder is molded by the magnetic field press, a bridge is not formed in the powder of the magnetic material due to the residual magnetism of the die and the core.

[Brief description of drawings]

FIG. 1 is a sectional view showing a powder filling device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing another state of the powder filling device.

FIG. 3 is a sectional view showing still another state of the powder filling device.

FIG. 4 is a sectional view showing still another state of the powder filling device.

FIG. 5 is a sectional view showing a powder filling device according to a second embodiment of the present invention.

[Explanation of symbols]

 1 die 2 core 3 lower punch 4 powder 5 upper punch 6 lid member 7 powder box 8 bellows hose 9 cylinder rod

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kosuke Agawa 2480 Kuno, Odawara-shi, Kanagawa Mikuni Corporation Odawara Plant

Claims (2)

[Claims] 1. A powder is dropped into a space where an outer peripheral surface is formed by a die and a bottom is formed by a lower punch and a core, and a lid member having a hole having the same shape as the outer circumference of the core is provided directly above the core. The core is raised in a state of being closely adhered to the upper end surface of the die at a position where the outer peripheral surface is formed by the die, the bottom is formed by the lower punch, and the inner peripheral surface is formed by the core. Powder filling method in powder molding for filling powder. 2. A powder filling apparatus for filling powder into a ring-shaped space having an outer peripheral surface formed by a die, a bottom formed by a lower punch, and an inner peripheral surface formed by a core. A lid member having a hole is provided movably between a position distant from the opening of the void and a position of covering the opening of the void and the hole being directly above the core; Powder molding in which the upper end surface of the core can be lifted from a position where the upper end surface is substantially at the height of the upper end surface of the lower punch to a position where it is at the upper end surface of the die when Powder filling equipment in.