JPH0320067Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to a powder molding press, and particularly to a powder molding press that is capable of producing a plurality of powder molded pressed products at once.

BACKGROUND ART When manufacturing an airtight terminal in which a lead wire is hermetically and insulatively sealed inside a metal outer ring through glass, a glass tablet is manufactured by press-molding fine glass powder in advance. When manufacturing such glass tablets, a powder molding press as shown in FIGS. 1 and 2 is generally used. In the figure, 1
1 is a hopper, and an arm portion 2 is rotatably attached to the lower end of the hopper, and a feeder portion 3 is provided at the tip of this arm portion 2. A shaft 1 is fixed to the base of the arm portion 2, and this shaft 4 is rotatably attached to a base 5. When the shaft 4 is rotated, the arm portion 2 and the feeder portion 3 slide on the table 5 and rotate. A cavity 6 for powder molding is formed on the trajectory of the feeder portion 3 of the table 5, and a lower punch 7 is disposed below the cavity 6, and an upper punch 8 is disposed above the cavity 6 so as to be movable up and down. . Inside the hopper 1, a powder 9 such as fine glass powder is stored.

Next, the procedure for molding this powder will be explained. First, the arm part 2 and the feeder part 3 are placed at the position A shown in two-dot chain line in FIG.
Insert. The powder 9 then flows through the arm portion 2 to the feeder portion 3. In this state, when the shaft 4 is rotated clockwise to move the arm portion 2 and the feeder portion 3 to the solid line position B in FIG. 1, the powder 9 in the feeder portion 3 is filled into the cavity 6. When the arm portion 2 and the feeder portion 3 return to the original position A, the powder 9 is rubbed off at the lower end of the feeder portion 3, and a predetermined amount of the powder 9 remains in the cavity 6. After this, the upper punch 8 descends and the powder 9 in the cavity 6 is removed.
Compression mold. Next, the upper punch 8 is raised, and then the lower punch 7 is raised to project the molded product onto the table 5, and the arm portion 2 and feeder portion 3 are again rotated toward the solid line position B. Then, a plate (not shown) disposed in front of the feeder section 3 in the advancing direction removes the molded product from above the lower punch 7 and stores it from the table 5 into a molded product receiving box (not shown). I will do it. Then, when the feeder section 3 comes to the solid line position B, the powder 9 is filled into the cavity 6 again. Thereafter, such operations are repeated to produce molded products such as glass tablets.

By the way, since the powder molding press described above has only one cavity 6, only one molded product can be obtained in one operation. Therefore, in the case of a molded product having a small shape, as shown in FIG.
7c and upper punches 8a, 8 although not shown
A so-called multi-cavity powder molding press has been considered in which the presses b and 8c are arranged so that a plurality of molded products can be manufactured at once. However, molded products manufactured using such a multi-cavity powder molding press have a drawback of large variations in weight.

The inventor investigated the cause of the above-mentioned weight variation and found the following. That is, the arm section 2 and the feeder section 3 are moving in an arc around the axis 4, and the moving speed of the feeder section 3 is set to be quite high for index up. Therefore, centrifugal force acts on the powder 9 in the feeder section 3, and the outer wall 3 of the feeder section 3
Since the powder 9 is pressed toward the side a, the amount of powder 9 filled in the cavity 7a closest to the outer wall 3a is maximum, and the amount of powder 9 thereafter decreases in the order of cavities 7b and 7c, resulting in variations in the weight of the molded product.

DISCLOSURE OF THE INVENTION Therefore, the main purpose of this invention is to provide a powder molding press with multiple cavities that does not cause weight variations in molded products.

To summarize, this idea can be summarized as follows: Powder is filled into each cavity by setting the flow resistance of the powder to be larger in cavities that are farther away from the center of rotation of the feeder, where the centrifugal force acting on the powder is greater, at locations corresponding to the cavities in the feeder. It is characterized by the provision of powder flow regulating means to make the amount uniform.

In other words, by providing a powder flow regulating means in the feeder section and making the flow of powder into each cavity constant, the amount of powder filled in each cavity can be made constant, thereby making the weight of the molded product uniform. It is possible. Therefore, by using the powder molding press of this invention, not only can a plurality of molded products be manufactured at once, efficiency is improved, but also the weight of the molded products can be made uniform.

BEST MODE FOR CARRYING OUT THE INVENTION FIG. 4 shows an enlarged sectional view of the feeder section 3 and cavities 6a to 6c of a three-cavity powder molding press. FIG. 5 shows an enlarged plan view of the same. The difference from FIG. 3 is that each cavity 6 in the feeder section 3
As an example of a powder flow regulating means in which the flow resistance of the powder 9 is set to be larger in the order of cavities 6a and 6b that are farthest from the center of rotation of the feeder section, circles along the extension line of cavities 6a and 6b are placed at locations corresponding to a and 6b. The reason is that arc-shaped rods 10a and 10b are provided. That is, a rod 10a having a width approximately equal to the diameter of the cavity 6a is placed on the cavity 6a furthest from the center of rotation, and a rod 10b having a width slightly smaller than the diameter of the cavity 6b is placed on the middle cavity 6b. No rod is placed on the cavity 6c closest to the center of rotation.

When powder molding is performed with the above configuration, the flow of the powder 9 is regulated by the rods 10a and 10b within the feeder section 3, and the powder 9 is transferred to each cavity 6a to 6c.
The filling amount becomes constant and a molded product with a uniform weight can be obtained.

The powder flow regulating means can be used not only when rods 10a and 10b of different widths are used as in the illustrated example, but also when rods of the same width are used in cavities 6a and 6.
They may be installed at different heights from b. Alternatively, a perforated plate or a lattice whose porosity becomes smaller as the distance from the center of rotation of the feeder section 3 decreases may be used.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the main part of a conventional single-cavity powder molding press. FIG. 2 is a cross-sectional view of the powder molding press of FIG. 1 taken along the - line. FIG. 3 is an enlarged sectional view of the feeder section and cavity of a conventional multi-cavity powder molding press. FIG. 4 is an enlarged sectional view of the feeder section and cavity of a multi-cavity powder molding press according to an embodiment of the present invention. FIG. 5 is also an enlarged plan view of the feeder section and cavity. 1... Hopper, 2... Arm part, 3... Feeder part, 4... Shaft, 5... Table, 6a to 6c... Cavity, 7a to 7c... Lower punch, 9... Powder, 1
0a, 10b...Powder flow regulating means (rod).

Claims (1)

[Claims for Utility Model Registration] 1. A hopper for storing powder, an arm portion extending diagonally downward from below the hopper, a feeder portion at the tip of the arm portion, and a shaft for rotating the arm portion and the feeder portion; A powder molding press comprising: a plurality of cavities formed on the axis trace of the feeder section; a lower punch disposed below each cavity; and an upper punch disposed above each cavity; Above the location corresponding to the cavity in the feeder section, the powder flow resistance is set to be greater for cavities that are farther from the center of rotation of the feeder section and have a greater centrifugal force acting on the powder, so that the amount of powder filled into each cavity is uniform. A powder molding press characterized by being provided with powder flow regulating means. 2. The powder molding press according to claim 1, wherein the powder flow regulating means is configured by arranging rods that are wider in cavities farther from the center of rotation of the feeder section. 3. The powder molding press according to claim 1, wherein the powder flow regulating means is configured by arranging a rod whose floating height from the cavity is greater as the cavity is farther from the center of rotation of the feeder section. . 4. The powder molding press according to claim 1, wherein the powder flow regulating means is configured by arranging a perforated plate or a lattice whose porosity is smaller as the cavity is farther from the center of rotation of the feeder section. .