JPH10118794A - Feeder in powder molding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a feeder in a powder molding apparatus capable of uniformly filling a raw material powder into a hole formed in an upper surface formed in a die, and increasing the speed of filling the raw material powder. I do. SOLUTION: The feeder 21 has a hopper 23 connected to a feeder main body 22 having an opening 22A on a lower surface thereof through a flexible raw material powder supply pipe 24. The raw material powder supply pipe 24 is connected to a supply pipe connection opening 25 provided on the rear wall 22B of the feeder body 22. And
On the rear wall portion 22B of the feeder body 22, a piezoelectric vibrator 27 is vertically arranged from the outside below the supply pipe connection opening 25.
It is mounted in several places. The piezoelectric vibrator 27 is controlled by a control means so as to vibrate for a predetermined time when the feeder main body 22 advances.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a feeder for supplying powder in a powder molding apparatus.

[0002]

SUMMARY OF THE INVENTION In powder metallurgy,
A raw material powder mainly composed of metal is formed by a powder forming apparatus into a green compact, and the green compact is heated in a sintering furnace to produce a sintered body. FIG. 7 shows an example of a conventional powder molding apparatus.
This will be described with reference to FIG. The mold 1 of the powder molding apparatus includes a die 3 fixed to a die plate 2, a core rod 4, a lower punch 5, and an upper punch 7 held by an upper punch holder 6.
Are located in the die 3. The lower punch 5 has a cylindrical shape and is fitted between the die 3 and the core rod 4 from below. The upper punch 7
Has a cylindrical shape and is fitted between the die 3 and the core rod 4 from above. Thus, a cavity 8 is formed in the die 3, that is, between the die 3, the core rod 4, and the upper punch 7 and the lower punch 5. In the figure, 9 is a flange protruding below the lower punch, 10 is a die fixing frame provided between the die 3 and the die plate 2, and 11 is a fixing frame provided between the die fixing frame 10 and the die plate 2. It is.

[0003] In the die 3 forming the cavity 8 of such a mold 1, the raw material powder P
The feeder 12 is connected to a feeder body 13 via a flexible raw material supply pipe 15 to which a hopper 14 is connected to the upper rear part of the feeder body 13. The feeder main body 13 has an opening 13A on the lower surface thereof.
7 is larger than the outer circumference. A feeder lever 16 is connected to a rear portion of the feeder body 13, and a drive mechanism (not shown) is connected to the feeder lever 16.
Are connected, and the feeder body 13 is moved forward and backward on the die plate 2 and the die 3 by the driving mechanism. In addition, the raw material powder supply pipe 15 is connected to a supply pipe connection opening 17 provided on the upper rear center of the feeder body 13.

When powder is formed, the feeder body 13 is advanced to a position above the lower punch 5 with the upper punch 7 raised and separated from the die 3 as shown in the figure. The raw material powder P is supplied from the stored hopper 14 into the feeder body 13 via the raw material powder supply pipe 15.
At the same time, the feeder body 13 reciprocates once or several times back and forth at a position above the opening 3A formed between the die 3, the core rod 4 and the lower punch 5.
Raw material powder P is supplied from inside 13 into opening 3A. When the filling of the raw material powder P into the opening 3A is completed, the feeder body 13 retreats and comes off the position above the opening 3A.
Then, the upper punch 7 descends and is fitted between the die 3 and the core rod 4, and the die 3 descends,
The raw material powder is compressed and solidified between the die 3 and the core rod 4 by the lower punch 5 and the upper punch 7 to form a green compact. Thereafter, the upper punch 7 is raised, and the die 3 is further lowered, and the green compact is extracted from the die 3 by the lower punch 5. Further, as described above, as the feeder body 13 advances for powder supply, the compact is discharged by the feeder body 13. Such a molding cycle is repeated.

In the feeder of the conventional powder molding apparatus as described above, the raw material powders P supplied to the feeder body 13 are held in a pile as shown in FIG. The raw material powder P easily causes bridging, making it difficult to fill the raw material powder P into the opening 3A formed in the die 3 at the time of molding, and forming a void or the like in the raw material powder P filled in the opening 3A. Sometimes. This tendency becomes more remarkable as the powder molding speed increases, which hinders the improvement of the molding speed. Further, the raw material powder P is biased to the rear side of the feeder main body 13 and a gravitational force G which presses the raw material powder remaining in the raw material powder supply pipe 15 is also applied. When the part and the rear part are compared, the front part tends to be less likely to be filled with the raw material powder P. For this reason, the density of the obtained cylindrical green compact may be uneven,
There is a problem that an error occurs in dimensions.

An object of the present invention is to solve these problems and to provide a feeder in a powder molding apparatus capable of uniformly filling a raw material powder in a hole formed in an upper surface formed in a die. . Another object of the present invention is to provide a feeder in a powder molding apparatus that can speed up filling of raw material powder.

[0007]

The feeder in the powder molding apparatus according to the first aspect of the present invention has an opening on the lower surface and has a feed pipe connected to a feed pipe connecting opening at an upper or rear feed pipe connecting opening. The raw material powder is supplied to the feeder main body, and the feeder main body advances on the die, fills the opening powder formed in the die with the raw material powder, and then retreats, wherein the feeder main body or the Vibration means is provided at the connection base end of the raw material powder supply pipe.

[0008] When filling the raw material powder into, for example, a cylindrical opening hole formed in the die, the feeder body is advanced toward the opening hole on the die, and the raw material is fed from the supply pipe into the feeder body. While supplying the powder, the feeder body is reciprocated back and forth on the die, and the raw material powder is dropped into the opening hole from inside the feeder body and filled.
At this time, by vibrating the feeder main body or the raw material powder supply pipe by the vibrating means, air and the like in the raw material powder supplied into the feeder main body can be removed and the raw material powder can be loosened. Therefore, a defective filling of the raw material powder or a bridge does not occur, and the molding speed can be improved. In addition, the raw material powder is degassed and loosened, and the gravity which presses the raw material powder remaining in the raw material supply pipe is dispersed and uniformly filled in the opening hole, so that the density of the obtained green compact is Can be stabilized.

Further, in the feeder in the powder molding apparatus according to the second aspect, the vibrating means is provided on a rear wall portion below a supply pipe connection opening of the feeder body. By adopting such a configuration, the raw material powder supplied into the feeder main body tends to be biased to the rear side, and particularly in this rear portion, a bridge is easily generated. The effect can be exhibited efficiently.

Further, in the feeder according to the third aspect of the present invention, the vibrating means is a piezoelectric vibrator. Since this piezoelectric vibrator is small, it can be easily attached to the feeder main body, has a large degree of freedom in its installation location and number, and is suitable for efficiently transmitting minute vibrations to the feeder main body.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the mold 1 of the powder molding apparatus has the same configuration as that shown in FIG. 7 described above, and includes a die 3, a core rod 4, a lower punch 5, and an upper punch holder 6 fixed to a die plate 2. The upper punch 7 is held and forms an opening 3 </ b> A opened on the upper surface between the die 3, the core rod 4, and the lower punch 5 in the die 3, and further, between the upper punch 7 and the lower punch 5. The cavity 8 is formed.

On the other hand, the feeder 21 in the present embodiment
A hopper is attached to the feeder body 22 having an opening 22A on the lower surface.
23 is connected via a flexible raw material powder supply pipe 24. The raw material powder supply pipe 24 is connected to the feeder body.
It is connected to a supply pipe connection opening 25 which is provided at the center upper side of the rear wall 22B and which is inclined downward and forward. Further, a feeder lever 26 is connected to the feeder body 22, and a drive mechanism (not shown) is connected via the feeder lever 26. Thus, the feeder main body 22 is linearly moved back and forth by the driving mechanism on the die plate 2 and the die 3 as shown by arrows. As shown in FIGS. 1 and 2, piezoelectric vibrators 27 as vibrating means are attached to the rear wall portion 22B of the feeder main body 22 at two locations above and below the supply pipe connection opening portion 25 from outside. . The piezoelectric vibrator 27 is detachably connected to a connector (not shown) by a cord 28, and this connector is connected to a power supply output and control means by a telescopic cord. Is controlled to vibrate for a certain period of time.

The operation of the above configuration will be described. At the time of powder molding, the feeder body 22 is advanced to a position above the lower punch 5 on the die plate 2 and the die 3 with the upper punch 7 raised and separated from the die 3. When the feeder body 22 moves forward, the die 3
And the core rod 4 is lowered, and the upper surfaces of the die 3 and the core rod 4 and the upper surface of the lower punch 5 are at the same height. Thereafter, the die 3 and the core rod 4 are raised.
An opening 3 </ b> A opened upward is formed between the die 3 and the core rod 4 and the lower punch 5. Then, the raw material powder P is supplied from the hopper 23 in which the raw material powder P is stored into the feeder main body 22 via the raw material powder supply pipe 24.
At the same time, as shown in FIG. 3, the feeder main body 22 reciprocates back and forth once to several times on the die 3 at a position above the opening 3A formed between the die 3 and the core rod 4 and the lower punch 5. I do. At this time, by activating the piezoelectric vibrator 27 to finely vibrate the feeder main body 22 itself, the raw material powder P in the feeder main body 22 can be degassed as shown in FIG. Is eliminated. In addition, it is possible to fill the opening 3A by loosening the raw material powder P and dispersing the gravitational force G from the raw material powder remaining in the raw material powder supply pipe 24. When the filling of the raw material powder P into the opening 3A is completed as described above, the feeder main body 22 retreats and comes off the position above the opening 3A. Subsequently, the descending upper punch 7 is fitted to the die 3 and the die 3 descends, and the raw powder P is compressed and hardened by the lower punch 5 and the upper punch 7 to form a green compact. You. Thereafter, the upper punch 7 is raised, and the die 3 is further lowered, and the green compact is extracted from the die 3 by the lower punch 5. Such a molding cycle is repeated.

As described in detail above, the feeder 21 in the powder molding apparatus of this embodiment has the opening 22A on the lower surface, and the raw material powder is inserted into the supply pipe connection opening 25 on the upper center of the rear wall of the feeder body 22. The raw material powder P is supplied to a feeder main body 22 that moves back and forth to which a supply pipe 24 is connected, and the feeder main body 22 advances on the die 3 to feed the raw material powder P into an opening 3A formed in the die 3. Since the feeder body 22 is provided with the piezoelectric vibrator 27 after the filling, the feeder body 22 is advanced toward the opening 3A on the die 3, and the feeder body When the raw material powder is supplied into the main body 22 and the feeder main body 22 is reciprocated back and forth on the die 3, the raw material powder P is dropped from the feeder main body 22 into the opening 3 </ b> A to be filled. The feeder main body 22 is vibrated by operating the feeder main body 22.
Air and the like in the raw material powder P supplied to the inside 22 can be removed, and the raw material powder P can be loosened. As a result, poor filling of the raw material powder P into the opening 3A, bridges, and the like do not occur, and the molding speed can be improved. Further, the raw material powder P is degassed and loosened by the vibration, and the gravitational force G that is pressed from the raw material powder remaining in the raw material powder supply pipe 24 is dispersed. Since the front part and the rear part are uniformly filled, the density of the obtained green compact can be stabilized. In particular, the raw material powder P supplied into the feeder main body 22 is supplied to the rear portion of the feeder main body 22 because the supply pipe connection opening 25 is provided at the rear, and the feeder main body 22 moves forward at the time of powder supply. In this embodiment, the piezoelectric vibrator 27 is provided on the rear wall portion 22B below the supply pipe connection opening 25 of the feeder main body 22. Therefore, the vibration of the piezoelectric vibrator 27 can efficiently exert the degassing and loosening effects of the raw material powder P. Further, in this embodiment, the piezoelectric vibrator 27 is employed as the vibration means, but since the piezoelectric vibrator 27 is small, it can be easily attached to the feeder main body 22, and its installation location and the number of installations are reduced. It can be easily changed, and is suitable for efficiently transmitting minute vibrations to the feeder body 22.

Next, a second embodiment of the present invention will be described with reference to FIGS. Since the feeder of the second embodiment has basically the same configuration as that of the first embodiment,
The same components are denoted by the same reference numerals, and detailed description thereof will be omitted. Although not particularly shown, the mold of the powder molding apparatus in the second embodiment has the same configuration as that of the first embodiment described above. Feeder 21 of the second embodiment
Is a band having a plurality of piezoelectric vibrators 27 as shown in FIG.
27A is wound around the base end 24A of the raw material powder supply pipe 24 connected to the supply pipe connection opening 25.

The operation of the above configuration will be described. At the time of powder molding, the feeder body 22 is advanced to a position above the lower punch 5 on the die plate 2 and the die 3 with the upper punch 7 raised and separated from the die 3. As shown in FIG. 6, when filling the raw material powder into the opening hole 3A, the piezoelectric vibrator is supplied at the time when the raw material powder P is supplied from the hopper 23 storing the raw material powder into the feeder main body 22 through the raw material powder supply pipe 24. Activate 27 and band 27
By finely vibrating the raw material powder supply pipe 24 at the connection base end 24A with the supply pipe connection opening 25 by A, the raw material powder P can be supplied into the feeder body 22 while being degassed. Bridges are eliminated.
At the same time, the feeder body 22 is on the die 3 and
The raw material powder P can be filled into the opening 3A by reciprocating once or several times back and forth at a position above the opening 3A formed between the die 3 and the core rod 4 and the lower punch 5. At this time, since the raw material powder P is supplied into the feeder body 22 in a state of being loosened by the piezoelectric vibrator 27, the molding speed can be improved. In addition, it is possible to distribute the gravitational force G from the raw material powder remaining in the raw material powder supply pipe 24 to fill the opening 3A. As a result, the front and rear portions of the opening 3A are uniformly filled with the core rod 4 as a reference, so that the density of the obtained green compact can be stabilized.

As is clear from the second embodiment, the piezoelectric vibrator 27 as the vibrating means does not need to be provided on the feeder main body 22, and is a portion through which the raw material powder P passes in a large amount, that is, the connection of the raw material powder supply tube 24 to the supply tube. It may be wound around the connection base end 24A with the opening 25.

Although the feeder in the powder molding apparatus of the present invention has been described with reference to the accompanying drawings, the present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the feeder of each of the above-described embodiments, the raw material powder heated by using a hopper 23 having a heating means such as an oil heater may be filled in the opening 3A. , A heating means such as a band heater or a cartridge heater can be provided in the feeder body 22. Also,
In the above-described embodiment, the piezoelectric vibrator 27 is used as the vibrating means. However, the present invention is not limited to this, and any device that can vibrate the feeder body 22 may be used. In addition, when the piezoelectric vibrator 27 is installed in the feeder body 22, the installation location is the same as the raw material powder P in the feeder body 22.
It is sufficient that the portion that comes into contact with a large amount is a portion that is effectively vibrated, and may be inside or outside the feeder main body 22. Further, the piezoelectric vibrator 27 may be provided on both the feeder main body 22 and the connection base end 24A of the raw material powder supply pipe 24 in both the first embodiment and the second embodiment.

[0019]

According to a first aspect of the present invention, there is provided a feeder having a feeder body having an opening on a lower surface and a feeder powder supply pipe connected to an upper or rear supply pipe connection opening. The raw material powder is supplied, and the feeder main body advances on the die, fills the raw material powder into the opening hole formed in the die, and then retreats, wherein the feeder main body or the raw material powder supply pipe is provided. Since the vibrating means is provided at the connection base end of the feeder body, the vibrating means vibrates the feeder main body or the raw material powder supply pipe when the raw material powder is dropped from the feeder main body into the opening hole and filled. Accordingly, the molding speed can be improved without the occurrence of poor filling of the raw material powder or bridging. In addition, the gravity of pressing the raw material powder remaining in the raw material supply pipe while being degassed and loosened is dispersed and uniformly filled in the opening holes, so that the density of the obtained green compact is stabilized. Can also be planned.

Further, in the feeder of the powder molding apparatus according to the second aspect, the vibrating means is provided on the rear wall portion below the supply pipe connection opening of the feeder main body, so that the feeder is supplied into the feeder main body. Although the raw material powder tends to be biased toward the rear side, the effect of deaeration and loosening of the raw material powder can be efficiently exhibited by the vibration of the vibration means.

Further, in the feeder in the powder molding apparatus according to the third aspect, since the vibrating means is a piezoelectric vibrator,
It is small in size, easily attached to the feeder main body, has a large degree of freedom in its installation location and number, and is suitable for efficiently transmitting minute vibrations to the feeder main body.

[Brief description of the drawings]

FIG. 1 is an overall sectional view showing a powder molding apparatus having a feeder in a powder molding apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the feeder of the first embodiment as viewed from a rear wall portion side.

FIG. 3 is an overall cross-sectional view showing a powder molding apparatus having a feeder for the powder molding apparatus according to the first embodiment when raw material powder is charged.

FIG. 4 is a schematic view showing a state in which the feeder body in the first embodiment is filled with the raw material powder.

FIG. 5 is a perspective view showing a feeder in a powder molding apparatus according to a second embodiment of the present invention.

FIG. 6 is a schematic diagram showing a state when a raw material powder is filled in a feeder body in the second embodiment.

FIG. 7 is an overall sectional view showing a powder molding apparatus having a conventional feeder.

FIG. 8 is a schematic diagram showing a state of raw material powder in a feeder body of the conventional feeder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Die of powder molding apparatus 3 Die 3A Opening hole 21 Feeder 22 Feeder main body 24 Raw material powder supply pipe 24A Connection base end 25 Supply pipe connection opening 27 Piezoelectric vibrator (vibration means) 27A band (vibration means)

Claims (3)

[Claims] 1. A raw material powder is supplied to a feeder body moving back and forth, having an opening on a lower surface and connected to a supply pipe connection opening at an upper or rear part, and the feeder body moves forward on a die. After filling the raw material powder into the opening hole formed in the die and then retreating, in the feeder of the powder molding apparatus, the vibration means is provided at the connection base end of the feeder body or the raw material powder supply pipe. A feeder in a powder molding apparatus. 2. The feeder according to claim 1, wherein said vibrating means is provided on a rear wall portion below a supply pipe connection opening of said feeder body. 3. The feeder according to claim 1, wherein the vibrating means is a piezoelectric vibrator.