JPH0214407Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a powder processing and pressure molding apparatus that presses and molds a material powder obtained by mixing and sizing a ferrite magnetic material powder and a binder into a predetermined shape.

FIG. 1 shows a conventional device of this type.

In Fig. 1, a is a female mold, b is an upper press mold and a lower press mold that fit into the empty space of the female mold a and move up and down, and d is a rotatable female mold with a plurality of female molds a disposed on the middle circumference. The disc-shaped support pedestal ``e'' is a hopper in which powdered material is stored, and the upper surface of the support pedestal d comes into sliding contact with the open lower end of the hopper e.

According to this configuration, the support base d rotates and the female mold a
When the hopper comes under the hopper, the material powder f in the female mold a is supplied from the hopper e into the empty space of the female mold a, and as the support d rotates, the material powder f in the female mold a is flattened with the lower surface of the hopper e. Then, the upper press die b descends to a predetermined position and presses the powder f so that the material powder f is molded into a predetermined size. After that, the upper press die b rises,
The lower press mold c also rises to a height where its upper surface coincides with the upper surface of the female mold a, the molded body is pushed out from the female mold a, and the molded body is blown with compressed air from the side and falls into the storage box.

In the above molding process, the material powder f filled in the hopper e is fed into the female mold a by its own weight, so if the amount of material powder in the hopper e changes depending on the amount used, the amount of material powder f filled in the female mold a will be supplied into the female mold a. The amount of material powder fluctuates.

Thus, when the upper press die b and the lower press die c are moved to a certain position and the material powder is pressurized and molded into a certain shape, the mold density changes, and when the molded body is sintered,
For example, there was an inconvenience that the dimensions of a 2.0φ cylinder varied by ±3%.

The purpose of the present invention is to eliminate the above-mentioned disadvantages of conventional devices.In a powder processing pressure molding device of the type that supplies material powder stored in a hopper in a cavity of a female mold, the hopper is It consists of a first hopper section for storing powder and a second hopper section for storing the material powder supplied from the first hopper section and supplying it to the cavity of the female mold, and from the first hopper section to the second hopper section. a supply device for supplying material powder to the second hopper section, and a sensor for detecting the storage level of the material powder disposed at a predetermined position of the second hopper section,
The feeding device is characterized in that it is activated when the sensor detects a drop in the storage level of material powder.

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

In Figures 2 to 4, 1 is female type, 2 ₁ ,
2 ₂ is an upper press mold and a lower press mold that fit into the cavity of the female mold 1 and move up and down, 3 is a rotatable medium plate-shaped support base on which a plurality of female molds 1 are arranged on the circumference; Reference numeral 4 denotes a hopper that stores the material powder 5 and supplies it into the female mold 1, and the hopper 4 receives the supply of the material powder 5 from the first hopper section ₄₁ that stores the material powder 5 and the first hopper section ₄₁ . and a second hopper part ₄₂ for storing the powder 5 and supplying the powder 5 into the cavity of the female mold 1 from the opening at the lower end. 6 is a rotating disk 6 that faces the opening at the lower end of the first hopper part ₄₁ with a gap of about 2 mm in between;
The rotary disk 6 is rotated by a motor 7. Reference numeral 8 denotes a partition plate fixed so as to be in sliding contact with the upper surface of the rotating disk 6 for causing the material powder 5 drawn onto the rotating disk 6 to fall into the second hopper part ₄₂ as it rotates; The plate 8, the rotating disk 6, and the motor 7 constitute a supply device 9 that supplies the material powder 5 from the first hopper section ₄₁ to the second hopper section ₄₂ . 10
₁ and 10 ₂ are a light emitting part and a light receiving part made of, for example, a phototransistor, which are disposed opposite to the tube wall of the second hopper part 4 ₂ , and the storage level of the material powder 5 decreases in both of them, and the light receiving part 10 ₂ When the sensor 10 receives light, the supply device 9 is activated by the output of the sensor 10.

Next, to explain its operation, the second hopper section 4 ₂
With the level of the material powder 5 in the mold as shown in the second figure, the support base 3 rotates and a plurality of female molds 1
The material powder 5 is sequentially supplied from the second hopper part ₄₂ , the upper press die ₂₁ is lowered to a predetermined position and the powder 5 is pressurized, and then the lower press die ₂₂ is moved to the female die 1 in the same way as in the conventional example. The molded body is pushed out from the female mold 1 by rising to the upper surface position, and the molded body is dropped into the storage box by blowing compressed air from the side. As the number of molded bodies increases, the material powder 5 in the second hopper part ₄₂ decreases,
Storage levels decrease. Thus, the light receiving part ₁₀₂ of the sensor 10, which had not received light until now, receives light, and the motor 7 starts rotating due to the output of the sensor 10, and the material powder 5 is transferred to the rotating disk 6 by the partition plate 8.
and falls into the second hopper section ₄₂ . Material powder 5
When the amount of light increases and the storage level reaches the position of the sensor 10, the light to the light receiving part ₁₀₂ is cut off.
The motor 7 is stopped, and the supply of material powder from the first hopper section 4 ₁ to the second hopper section 4 ₂ is stopped.

As a result of repeating the above operations, the level of the material powder 5 in the second hopper part ₄₂ is always kept constant, so that the material powder 5 supplied into the female mold 1 is
The pressure applied to the female mold 1 is always constant, and a constant amount of the sensor 5 is always filled in the female mold 1. Therefore, a molded body having a constant molding density can be obtained. When the molded body is, for example, a pressurized sensor made of a mixture of ferrite magnetic material powder and a binder, the dimensional error of a cylindrical core of, for example, 2.0 mmφ obtained by sintering this is within ±0.5%. It was hot.

In this way, according to the present invention, the hoppa is the first
A supply device configured with a hopper section and a second hopper section, which supplies material powder from the first hopper section to the second hopper section, and detects the storage level of the material powder disposed at a predetermined position in the second hopper section. a sensor, the feeding device being activated when the sensor detects a drop in the predetermined storage level of the material powder;
The amount of material powder supplied from the second hopper part into the cavity of the female mold is always constant, and as a result, the density of the molded product molded by the pressing die is always constant, and when this molded product is sintered, sintering is required. This has the effect of producing a product with less variation in subsequent dimensions.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional powder processing and pressure molding device, Fig. 2 is a cross-sectional view of an embodiment of the present invention, Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2, and Fig. 4 is a cross-sectional view of a conventional powder processing and pressure molding device. A sectional view taken along the line BB in FIG. 2 is shown. 1...Female type, 2 ₁ , 2 ₂ ...Upper press type, lower press type, 3
... Disk-shaped support stand, 4 ... hopper, 4 ₁ ... 1st
Hopper part, 4 ₂ ...Second hopper part, 5...Material powder,
6... Rotating disk, 7... Motor, 8... Partition plate,
9... Supply device, 10... Sensor.

Claims (1)

[Scope of utility model registration request] In a powder processing pressure molding device of the type that feeds material powder stored in a hopper into the cavity of a female mold,
The hopper consists of a first hopper section that stores the material powder and a second hopper section that stores the material powder supplied from the first hopper section and supplies it to the cavity of the female mold, and the first hopper section a supply device for supplying the material powder from the material powder to the second hopper section; and a sensor for detecting the storage level of the material powder disposed at a predetermined position in the second hopper section, A powder processing and pressure molding device, characterized in that the device is activated when a drop in the storage level of the powder is detected.