JPH0740494Y2 - Powder production equipment - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder producing apparatus for producing metal powder by a gas atomizing method, and more particularly to a powder producing apparatus capable of easily aligning a melt nozzle and a gas jet nozzle.

[0002]

2. Description of the Related Art As a device for producing a metal powder, a powder producing device using a gas atomizing method has been conventionally known. This apparatus stores a metal sample in a melting crucible, melts it by induction heating, and injects it into a lower injection chamber from a molten metal nozzle provided at the bottom of the melting crucible. At this time, an inert gas is jetted at a high speed from a gas jet nozzle provided at the lower end of the molten metal nozzle, and the molten metal jetted from the molten metal nozzle is made into metal powder by a gas atomizing method.

[0003]

In the conventional powder production apparatus configured as described above, a ready-made gate valve that is generally used as a gate valve for opening and closing the opening of the gas jet nozzle is used. Next, it hindered the miniaturization of the device. Further, there is a problem that it is difficult to airtightly separate the melting part and the upper injection chamber by the gate valve, and the metal sample is oxidized. .

The present invention has been made in view of the above points, and provides a powder production apparatus capable of miniaturizing a gate valve for opening and closing a lower opening of a gas jet nozzle and further making a melting portion a high vacuum. The purpose is to

[0005]

In order to achieve the above object, the present invention relates to a gas atomizing method in which a metal sample in a melting crucible is melted by induction heating and a melt nozzle is provided at the bottom of the melting crucible. In a powder production apparatus for producing a metal powder by injecting with, a melting part for housing the melting crucible, and a high-pressure gas attached to the lower part of the melting part and on the outer periphery of the molten metal nozzle protruding from the lower part of the melting part. A gas jet nozzle for injecting the gas jet nozzle, a gate valve slidably mounted along the lower surface of the gas jet nozzle for opening and closing a central hole of the gas jet nozzle, and a fluid cylinder for driving the gate valve to open and close. In addition, the output shaft of the fluid cylinder and the gate valve are engaged via a tapered surface.

[0006]

According to the above construction, since the gate valve is opened and closed by the fluid cylinder, the opening and closing mechanism of the gate valve can be made small and simple. Further, by advancing the output shaft of the fluid cylinder, the gate valve can be raised through the tapered surface, and the gate valve can be brought into close contact with the lower surface of the gas jet nozzle. As a result, by closing the gate valve during melting of the metal sample, it is possible to create a high vacuum in the melting chamber and prevent oxidation of the sample.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the powder producing apparatus of the present invention will be described below with reference to the drawings.

1 to 3 show the configuration of an embodiment of the present invention. FIG. 2 shows a schematic configuration of the powder production apparatus according to this example. An upper injection chamber 2 is fixed on the gantry 1, and a lower injection chamber 3 is provided below the upper injection chamber 2 so as to be in close contact therewith. The lower injection chamber 3 is supported by a carriage 4, and a recovery pot 5 for recovering the manufactured powder is detachably attached to the lower end of the lower injection chamber 3. The upper injection chamber 2 is provided with a front view window 6, a hot water receiving mechanism 7, and an internal lighting device 8, and a melting portion 9 is attached to the upper portion.

A gas jet nozzle 10 to be described later is provided between the melting section 9 and the upper injection chamber 2, and a gas release valve 11 is connected to the upper injection chamber 2. A melting chamber 12 is provided above the melting unit 9, and the inside of the melting chamber 12 is evacuated by a vacuum exhaust device 13. In addition, in the melting chamber 12, a sample addition rod 14 for adding a metal sample and a shelving rod 15 are added.
And are attached. Reference numeral 16 shown in FIG. 2 is a surge tank, and reference numeral 17 is a compound meter.

FIG. 3 shows a detailed structure of the melting portion 9. A coil 22 for induction heating is wound around the outer cylinder 21 of the melting section 9, and a melting crucible 24 is placed on a bottom plate 23 inside the outer cylinder 21 via a carbon sheet 25. . Also the outer cylinder 21
Of the melting crucible 24, the bottom plate 23, and the upper wall of the upper injection chamber 2 are concentrically provided with holes 24a, 23a and 23a, respectively. 2a is formed. The molten metal nozzle 27 is attached to the holes 24a and 23a, and the gas jet nozzle 10 is attached to the hole 2a.

The upper end surface of the molten metal nozzle 27 is formed with a concave portion 27a having an inverted conical shape of about 90 degrees, and the cylinder 18 shown in FIG.
Thus, the molten metal nozzle 27 is opened and closed by the stopper 28 that is driven up and down via the rod 19. Also melt nozzle 27
The lower end of is fitted into the central hole 10a of the gas jet nozzle 10, and a large number of unillustrated injection holes are concentrically formed on the outer periphery of the central hole 10a of the gas jet nozzle 10. Then, an inert gas such as Ar supplied through the pipe 29 passes through the jet nozzle 10 and is jetted from the jet holes.

The outer circumference of the gas jet nozzle 10 is fitted to the inner circumference of the hole 2a of the upper injection chamber 2 via the O-ring 30 so as to be slidable in the axial direction and airtight. Further, between the gas jet nozzle 10 and the shoulder of the melt nozzle 27, elastic kaool packing 31 is sandwiched. Further, the lower end of the molten metal nozzle 27 is fitted in the center hole 10a of the gas jet nozzle 10, and the center hole 10a is expanded in diameter downward. Then, the gas jet nozzle 10 is attached to the upper injection chamber 2 by a bolt 32 after being positioned as will be described later. The bolt 32 is fixed to the upper injection chamber 2 by screwing, and the gas jet nozzle 10 is movable in the axial direction with respect to the bolt 32. Further, the bolt 33 controls the rising end of the gas jet nozzle 10.

A gate valve 34 is provided on the lower surface of the gas jet nozzle 10 so as to be movable along the lower surface. Figure 1
The drive mechanism of the gate valve 34 is shown in FIG. An air cylinder 41 is fixed to the inner surface of the upper portion of the upper injection chamber 2,
The output shaft 42 of 41 is parallel to the upper inner surface of the upper injection chamber 2. The base end of a bar 43 is fixed to the tip of the output shaft 42, and a tapered surface 43a is formed in the middle of the bar 43.
Further, a tapered surface 34a having the same angle is also formed on the lower surface of the gate valve 34, and both tapered surfaces 43a and 34a are fixed after positioning as described later. Further, a tapered surface 43b is also formed at the tip of the bar 43, and slidably engages with a tapered surface 2a formed on the upper injection chamber 2 side and having the same angle. Reference numerals 43c and 43d are relief grooves for both ends of the lower surface of the gate valve 34.

In the powder producing apparatus constructed as described above, the melting crucible 24 containing the metal sample is placed in the melting section 9 which is evacuated by the vacuum evacuation device 13, and the melt nozzle 27 is It is closed by a stopper 28.
When a high frequency voltage is applied to the coil 22, the metal sample in the melting crucible 24 is induction-heated and melted. Next, the molten metal is pressurized in the melting chamber 12 so as to be discharged, and at the same time the gate valve 30 is opened, the molten metal stopper 28 is raised by driving the air cylinder 31, and the initial molten metal discharge timer is used to set the initial molten metal discharge setting. Supply inert gas from 10,
It is injected from the injection hole to the outer periphery of the lower end of the molten metal nozzle 27. As a result, the molten metal becomes a powder by the gas atomizing action, and is recovered in the recovery pot 5 through the injection chambers 2 and 3. The inert gas injected into the upper injection chamber 2 is released to the outside via the gas release valve 11.

When the inert gas is being ejected from the gas jet nozzle 10, the gate valve 34 is retracted in the direction indicated by the arrow A by the action of the air cylinder 41 to release the central hole of the gas jet nozzle 10. When the injection of the inert gas from the gas jet nozzle 10 is stopped, the gate valve 34 moves in the direction of the arrow B by the action of the air cylinder 41, closing the central hole of the gas jet nozzle 10 and blowing air into the melting portion 9. Prevent intrusion. At this time, the O provided on the upper surface of the gate valve 34
The ring 44 comes into contact with the outer periphery of the central hole on the lower surface of the gas jet nozzle 10 and is hermetically sealed.

By moving the relative position of the gate valve 34 and the bar 43 via the tapered surfaces 34a, 43a, the height of the gate valve 34 when the valve is closed can be adjusted. When the bar 43 moves a predetermined stroke in the direction of arrow B,
The tapered surface 2a formed on the upper injection chamber side and the tapered surface 43b formed at the tip of the bar 43 engage with each other, and the gate valve 34 comes into close contact with the lower surface of the gas jet nozzle 10 through the O-ring 44.

According to this embodiment, since the gate valve 34 is driven to open and close by the air cylinder 41 attached to the upper injection chamber 2, the structure of the device can be simplified and downsized. Further, when the gate valve 34 is closed during melting of the metal sample, the gate valve 34 is pushed up to the gas jet nozzle 10 side and comes into close contact therewith, so that the inside of the melting part 9 can be made to have a high vacuum and the sample can be prevented from being oxidized. .

[0018]

As described above, according to the powder manufacturing apparatus of the present invention, the gate valve opening / closing drive mechanism can be made simple and compact. Further, since the gate valve can be brought into close contact with the gas jet nozzle, it is possible to prevent the sample from being oxidized by setting a high vacuum inside the melting portion.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the structure of a gate valve according to an embodiment of the powder manufacturing apparatus of the present invention.

FIG. 2 is a front view showing a schematic configuration of a powder production apparatus according to an embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view showing the configuration of the melting section of FIG.

[Explanation of symbols]

9 Melting part 10 Gas jet nozzle 10a Center hole 24 Melting crucible 27 Molten metal nozzle 31 Kao wool packing (elastic member) 34 Gate valve 41 Air cylinder (fluid cylinder) 42 Output shafts 34a, 43a Tapered surface

Claims (1)

[Scope of utility model registration request] 1. A powder production apparatus for producing a metal powder by melting a metal sample in a melting crucible by induction heating and injecting it by a gas atomizing method through a melt nozzle provided at the bottom of the melting crucible, A melting part for accommodating a melting crucible, a gas jet nozzle attached to a lower part of the melting part, for injecting a high-pressure gas onto the outer periphery of the molten metal nozzle protruding from the lower part of the melting part, and a lower surface of the gas jet nozzle. A gate valve that is slidably mounted and that opens and closes the central hole of the gas jet nozzle; and a fluid cylinder that drives the gate valve to open and close, and the output shaft of the fluid cylinder and the gate valve are tapered. A powder production apparatus characterized in that they are engaged via a surface.