JPH07150202A - Feeder of powder molding press - Google Patents

Abstract

PURPOSE:To prevent the intrusion of the raw material powder which is ought to exist upper to the lower part of a green compact and to pack the respective raw material powders uniformly transversely and longitudinally into a die in two-layer molding by packing two kinds of the raw material powders to two layers, upper and lower, into the die. CONSTITUTION:A first powder chamber 24 and a second powder chamber 25 are segmented and formed by arraying these chambers on the right and left into a feeder box 22. This feeder box 22 is advanced to position the first powder chamber 24 above the hole 1a of the die 1 and to pack the first raw material powder P1 therein. Next, the feeder box 22 is moved horizontally to position the second powder chamber 25 above the hole 1a of the die 1 and to pack the second raw material powder P2 therein. The feeder box 22 is thereafter retreated as it is. The feeder box moves transversely and longitudinally respectively at the time of packing the respective raw material powders, by which the uniform packing is executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder molding press feeder used in powder metallurgy.

[0002]

2. Description of the Related Art In powder metallurgy, a raw material powder containing a metal as a main component is compression molded by a powder molding press to obtain a green compact, which is then heated and sintered in a sintering furnace. Be seen. In addition, in such powder metallurgy, a two-layer material is also manufactured using two kinds of raw material powders.

An example of a conventional powder molding press for two-layer molding will be described with reference to FIG. This Figure 4
Particularly, it shows an outline of a die and a feeder for filling the raw material powder into the die. The die is for molding a cylindrical green compact G, and the die 1 is used as a die member.
And a core rod 2, a lower punch 3 and an upper punch 4. The die 1 is fixed to a die plate 6,
It has a vertical hole 1a and forms the outer peripheral surface of the green compact G. The core rod 2 is positioned coaxially inside the die 1 and forms the inner peripheral surface of the green compact G, and the position relative to the die 1 is fixed. The lower punch 3 is slidably fitted between the die 1 and the core rod 2 from below and in the vertical direction, and forms the lower end surface of the green compact G. The upper punch 4 is slidably fitted between the die 1 and the core rod 2 from above and in the vertical direction, and forms the upper end surface of the green compact G.

The feeder 11 is provided with a feeder box 12 whose lower surface is opened. Although not shown, the feeder box 12 slides only in the front-rear direction on the die plate 6 and the die 1 by transmitting power from a motor. A first powder chamber 14 and a second powder chamber 15 are formed in the feeder box 12 side by side by a partition wall 13. The lower surface opening of each powder chamber 14 and 15 is larger than the upper surface opening of the hole 1a of the die 1. In addition, the hose connecting portion 1 is provided on the upper surface of the feeder box 12 so as to face the powder chambers 14 and 15, respectively.
6 and 17 are provided. One end of each hose 18, 19 is connected to each of these hose connection parts 16, 17,
Although not shown, the other ends of the hoses 18 and 19 are connected to hoppers, respectively.

Next, the operation of the above configuration will be described. This powder molding press is of the withdrawal type, and the filling type is suction filling. In the first powder chamber 14 on the rear side of the feeder box 12, from the hopper to the first
The raw material powder P1 is supplied, and the second raw material powder P2 is supplied into the second powder chamber 15 on the front side from another hopper. Then, at the time of filling, as shown by the solid line in FIG.
With the upper surface of the die 1 and the upper surface of the lower punch 3 aligned, that is, with the lower punch 3 blocking the entire hole 1a of the die 1, the feeder box 11 advances (arrow A) and its second powder chamber 15 passes through the hole 1a of the die 1, the first powder chamber
14 is located above the hole 1a of the die 1. In this state, as the die 1 rises, the lower punch 3 lowers relative to the die 1 as shown by the chain line, and as a result,
From the first powder chamber 14 into the hole 1a of the die 1, the first raw material powder P1
Is sucked. Then, as shown in FIG. 4B, the feeder box 11 is retracted (arrow B), and the second powder chamber 15 is located above the hole 1a of the die 1. In this state,
As the die 1 further rises, as shown by the chain line, the lower punch 3 further lowers relative to the die 1, and accordingly, the lower punch 3 moves from the second powder chamber 15 into the hole 1a of the die 1. The raw material powder P2 of 2 is sucked. Thus, die 1
Inside the hole 1a, two kinds of raw material powders P1 and P2 are filled in two layers, upper and lower.

Then, after the feeder box 11 is further retracted and separated from the die 1, as shown in FIG. 4 (c),
The descending upper punch 4 is fitted into the die 1 from above, and the die 1
The raw material powders P1 and P2 in the inside are pressed from above and compressed. Also,
As the die 1 descends, the lower punch 3 pressurizes and compresses the raw material powders P1 and P2 in the die 1 from below. Thus
Two layers of green compacts G are formed in the axial direction. Then die 1
Is further lowered, the lower punch 3 pushes up the powder compact G in the die 1 to extract it. Further, the upper punch 4 rises from that time. Furthermore, the green compact G extracted
The feeder box 12 that has advanced in the next cycle
Paid out by.

[0007]

However, in the above-mentioned conventional feeder 11, since the two powder chambers 14 and 15 are formed in the front and rear in the feeder box 12 which moves only in the front-rear direction, the following problems occur. Was occurring. First, the first raw material powder P1 is filled first, that is, on the lower side.
Before that, since the second powder chamber 15 of the feeder box 12 passes over the lower punch 3, at that time, the second raw material powder P2 is placed on the lower punch 3 and originally the first raw material is used. The second raw material powder P2 is mixed in the lower part of the green compact G which should be made of the powder P1. In particular, as shown in FIG. 5, in general, the tip surface of the punch 3 is formed with a concave slope 3a for holding the raw material powder at the corner portion of the green compact G which is likely to collapse. Although the second powder chamber 15 passes over the lower punch 3 with the upper surfaces of the die 3 and the die 1 aligned with each other, the raw material powder P2 is easily caught on the lower punch 3 by being caught by the concave slope 3a. is there.

Further, generally, the packing density of the raw material powders P1 and P2 becomes high in the vicinity of the surface of the feeder box 12 facing the moving direction, but since the feeder box 12 moves only in the front-back direction, FIG. As shown by cross-hatching, the density of the front and rear portions of the hole 1a of the die 1 is high, while the density of the left and right portions is low, and the raw material powders P1, P2
Cannot be filled uniformly.

The present invention is intended to solve such a problem, and when the two kinds of raw material powders are filled in the mold in the upper and lower two layers, the raw material powder to be positioned above is the green compact. An object of the present invention is to provide a feeder for a powder molding press which can prevent the raw material powder from being mixed into the lower part and can uniformly fill each raw material powder in the front, rear, left and right directions.

[0010]

In order to achieve the above object, the present invention provides a feeder of a powder molding press for filling two kinds of raw material powder into upper and lower two layers in a hole of a mold member,
A feeder box that slides on the mold member, in which a first powder chamber and a second powder chamber each having a lower surface opening larger than an upper surface opening of the hole of the mold member are laterally arranged side by side A forward-backward moving mechanism for moving the feeder box in the front-rear direction, a position where the first powder chamber overlaps the hole of the mold member, and a second powder chamber where the feeder box overlaps the mold member. It has a left-right movement mechanism that moves it left and right between the position where it overlaps with the hole.

[0011]

In the feeder of the powder molding press of the present invention, when the two kinds of raw material powders are filled into the holes of the die member in the upper and lower two layers, first, the feeder box is advanced on the die member, and the feeder box is moved forward. The first powder chamber of the above is located on the hole of the mold member. In this state, the first raw material powder is filled into the holes of the mold member from the first powder chamber. Then,
The feeder box is moved laterally to position its second powder chamber over the hole in the mold member. In this state, the second raw material powder is filled into the holes of the mold member from the second powder chamber. Then, the feeder box is retracted and separated from the hole of the mold member. With this configuration, the second powder chamber does not pass over the hole of the mold member before the first raw material powder is filled, and the second raw material powder to be positioned above is the green compact. Does not mix into the bottom. Further, since the feeder box moves in the front-rear direction and in the left-right direction at the time of filling each raw material powder, each raw material powder is uniformly filled in the front-rear direction and the left-right direction.

[0012]

EXAMPLE An example of the feeder of the powder molding press of the present invention will be described below with reference to FIGS. Since the structure of the mold is the same as that of the conventional one shown in FIG. 4 described above, the corresponding parts are designated by the same reference numerals and the description thereof will be omitted.

A feeder 21 for filling two kinds of raw material powders P1 and P2 into upper and lower two layers in a hole 1a of a die 1 which is a die member is provided with a feeder box 22 having an opened lower surface. In the feeder box 22, a first powder chamber 24 and a second powder chamber 25 are formed side by side by a partition wall 23. The lower surface openings of the powder chambers 24 and 25 are larger than the upper surface openings of the holes 1a of the die 1, respectively. Also, each powder chamber 24,
Hose connecting portions 26 and 27 are provided on the upper surface of the feeder box 22 so as to face the respective 25. One end of each hose 28, 29 is connected to each of these hose connecting portions 26, 27, and the other end of each of these hoses 28, 29 is connected to a hopper (not shown). The feeder box 22, which slides on the die plate 6 and the die 1, is moved in the front-rear direction by driving the forward-backward moving mechanism 31, and is driven by the left-right moving mechanism 32 to move the first powder chamber. It is adapted to move left and right between a position where 24 overlaps the hole 1a of the die 1 and a position where the second powder chamber 25 overlaps the hole 1a of the die 1.

The structures of the forward / backward moving mechanism 31 and the left / right moving mechanism 32 will be described with reference to FIG. Reference numeral 33 is a frame, and the frame 33 has a pair of parallel left and right arm portions 34. The arm portions 34 are guided by a pair of parallel left and right rails 35 fixed on the die plate 2, so that the frame 33 can move only in the front-rear direction. A drive lever 37 is connected to the rear portion of the frame 33 via a joint 36. This drive lever
37 transmits the power from a motor (not shown) provided in the powder molding press to the frame 33 to drive the frame 33 in the front-back direction.
In addition, the feeder box 22 is supported between the left and right arm portions 34 of the frame 33 via a support rod 41 so as to be movable only in a predetermined range in the left-right direction. Support rod 41
Are fixed to the left and right sides of the feeder box 22 one by one in front and back, and slidably penetrate through the arm portion 34 to be supported. Then, both arm portions 34 define the left limit position and the right limit position of the feeder box 22. Also, the frame 33
At the rear of both arms 34 of the air cylinder 42
Is fixed. The piston rod 43 that moves to the left and right of these air cylinders 42 is the feeder box.
It is connected to a projecting piece 44 provided at the center of the rear surface of 22. That is, both air cylinders 42 form a drive source for moving the feeder box 22 left and right.

Next, the operation of the above configuration will be described. The powder molding press is of the withdrawal type, and the filling method is suction filling. The first raw material powder P1 is supplied from the hopper into the first powder chamber 24 on the right side of the feeder box 22, and the second raw material powder P2 is supplied from the other hopper into the second powder chamber 25 on the left side. To be done. Then, at the time of filling, first, with the feeder box 22 in the left limit position with respect to the frame 33, the feeder box 22 moves forward together with the frame 33 as shown by an arrow C in FIGS. 1 (a) and 2 (a). Then, the first powder chamber 24 on the right side is located above the hole 1a of the die 1. In this state, when the die 1 is raised, the lower punch 3 is lowered relative to the die 1, and as a result, as shown in FIG. 2A, the die 1 is moved from the first powder chamber 24. The first raw material powder P1 is sucked into the hole 1a. Then, as shown by the arrow D in FIG. 1B, the feeder box 22 is moved to the right by the drive of the air cylinder 42, and the second powder chamber 25 is located above the hole 1a of the die 1. In this state, when the die 1 is further raised, the lower punch 3 is further lowered relative to the die 1 as shown by the chain line, and accordingly,
As shown in FIG. 2B, the second raw material powder P2 is sucked into the hole 1a of the die 1 from the second powder chamber 25. Thus
Inside the hole 1a of the die 1, two types of raw material powders P1 and P2 are filled in two layers, upper and lower. Then, as shown by an arrow E in FIGS. 1 (b) and 2 (b), the feeder box 22
Moves backward with the frame 33 and leaves the die 1. After that, the feeder box 22 is moved to the left by the drive of the air cylinder 42 as shown by the arrow F.

Then, in this way, the feeder box 22
2C, the descending upper punch 4 is fitted into the die 1 from above and the raw material powder in the die 1 is retracted.
Compress P1 and P2 by pressing from above. Further, as the die 1 descends, the lower punch 3 causes the raw material powder P1,
P2 is pressed from below and compressed. Thus, the two layers of green compact G are formed in the axial direction. Thereafter, the die 1 is further lowered, and the lower punch 3 pushes up the green compact G in the die 1 to extract it. Further, the upper punch 4 rises from that time. Further, the extracted green compact G is discharged by the feeder box 22 that has advanced in the next cycle.

According to the configuration of the above-described embodiment, the first powder chamber 24 and the second powder chamber 25 are formed side by side in the feeder box 22, and the feeder box 22 is formed.
It can be moved not only in the front-back direction but also in the left-right direction.
By moving 22 into a U shape, the first raw material powder
Before the filling of P1, the second powder chamber 25 does not pass over the hole 1a of the die 1, and the second raw material powder P2, which should be located above, does not mix into the lower part of the green compact G. . In addition, each raw material powder
When filling P1 and P2, the feeder box 22 moves in the front-back direction and in the left-right direction, respectively, that is, when filling the first raw material powder P1, the feeder box 22 moves.
22 moves to the front C and then to the right D, and when the second raw material powder P2 is filled, the feeder box 22 moves to the right D and then to the rear E.
Therefore, the raw material powders P1 and P2 are uniformly filled in the front, rear, left and right.

In order to fill the raw material powders P1 and P2 more evenly in the front, rear, left and right, the feeder box 22 may be vibrated finely in the front, rear, left and right when the raw material powders P1, P2 are filled. .

The present invention is not limited to the above embodiment, and various modifications can be made. For example,
In the above embodiment, the molding method was the withdrawal method, but the present invention can be applied to other molding methods such as double-press molding. The present invention can be applied to both the filling method and the drop filling. Further, the green compact to be molded is not limited to the cylindrical one. Further, the forward / backward moving mechanism and the left / right moving mechanism of the feeder box are not limited to those in the above embodiment. For example, a universal joint may be used to support the feeder box so that it can move left and right.

[0020]

According to the present invention, the first powder chamber and the second powder chamber are arranged side by side in the feeder box to form partitions, and when the raw material powder is filled, the feeder box is first moved forward and the feeder box is moved forward. The first powder chamber of the box is located on the hole of the mold member, the first raw material powder is filled into the hole of the mold member from the first powder chamber, and then the feeder box is moved laterally. By positioning the second powder chamber above the hole of the mold member, filling the second raw material powder into the hole of the mold member from the second powder chamber, and then retracting the feeder box, The second raw material powder, which should be located at
Further, each raw material powder can be uniformly filled in the front, rear, left and right.

[Brief description of drawings]

FIG. 1 is a schematic horizontal sectional view showing an embodiment of a feeder of a powder molding press of the present invention.

FIG. 2 is a schematic vertical sectional view of the same as above.

FIG. 3 is a plan view of the same.

FIG. 4 is a vertical sectional view showing an example of a feeder of a conventional powder molding press.

FIG. 5 is an enlarged cross-sectional view of the upper and lower punches near the upper end thereof.

FIG. 6 is a plan view showing the same problem.

[Explanation of symbols]

 1 die (die member) 1a hole 21 feeder 22 feeder box 24 first powder chamber 25 second powder chamber 31 back-and-forth moving mechanism 32 left-right moving mechanism P1 first raw material powder P2 second raw material powder

Claims (1)

[Claims] 1. A feeder of a powder molding press for filling two kinds of raw material powder into upper and lower two layers into a hole of a mold member,
A feeder box that slides on the mold member, in which a first powder chamber and a second powder chamber each having a lower surface opening larger than an upper surface opening of the hole of the mold member are laterally arranged side by side A forward-backward moving mechanism for moving the feeder box in the front-rear direction, a position where the first powder chamber overlaps the hole of the mold member, and a second powder chamber where the feeder box overlaps the mold member. A feeder for a powder molding press, which has a left-right movement mechanism that moves left and right between a position where it overlaps with a hole.