JPS6239060B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method suitable for compressing and solidifying granular materials such as metal powder and casting sand.

For example, metal powder has poor fluidity and high frictional resistance, so when the metal powder is filled into a die and compressed to solidify, the state of filling the die is extremely poor. Therefore, in order to compress and solidify metal powder into a complex shape, it is necessary to apply a pressure of 8 tons/cm ² or more to the die, and as a result, the equipment is large, rigid, heavy, and expensive. It's summery.

The present invention was made in view of the above circumstances, and
The purpose is to provide a method that can densely fill a split model or the like with granular material such as metal powder without applying vibrations, and can compress and solidify the granular material at a relatively low pressure. Hereinafter, embodiments of the present invention will be described in detail based on the drawings. The one shown in FIG. 1 is for solidifying metal powder, and is placed on a fixed table 2 with an opening 1 of an appropriate size, and a lid member 4 with pores 3, 3 through which fluid can flow. of,
Place the pores 3, 3 above the opening 1,
A cylindrical split frame body 5 is placed on the lid member 4.
Load it by closing its bottom opening with
A predetermined metal powder M is put into the space formed by the lid member 4 and the frame body 5, and then the upper end opening of the frame body 5 is hermetically closed with the cover member 6 and the seal member 7. The interior of the cover member 6 is communicated via a conduit 8 and an on-off valve 9 to a high-pressure liquid generator 10 that generates high-pressure water or the like of about 100 kg/cm ² . In this way, the upper end opening of the frame 5 is covered by the cover member 6.
When the opening/closing valve 9 is opened and a high-pressure liquid is supplied into the hollow chamber 11 formed on the upper surface of the metal powder M by closing it with a The water then flows through and is discharged to the outside. As the high-pressure liquid flows through the metal powder M, each layer in the height direction of the metal powder M receives a force from the layer immediately above it and a downward force corresponding to the pressure gradient, and as a result, the metal powder M becomes denser. It is filled, compressed and fixed.

Thereafter, the on-off valve 9 is closed to stop the supply of high-pressure liquid, the cover member 6 is removed, and the solidified metal powder M is extracted from the frame 5, dried, and further sintered to form the metal powder. A sintered body is obtained.

In addition, an antioxidant is added when the metal powder dislikes oxidation, and a binder is added when strength is required.

Next, what is shown in Fig. 2 is a case where a mold is made by solidifying casting sand, and an opening 21 of an appropriate size is used.
On a fixed table 22 equipped with
is placed above the opening 21, and the model plate 2 is placed on top of the opening 21.
A predetermined casting flask 25 is placed on top of the casting flask 25, and casting sand S coated with starch and bentonite is poured into the space formed by the model plate 24 and the flask 25. Cover member 26 and seal member 2
7 to close airtight. Note that cover member 2
6 has a conduit 28 and an on-off valve 29, and has a capacity of 50 kg/
High-pressure liquid generator 3 that generates high-pressure water of about ² m2
0, and to a compressed air source 33 via a conduit 31 and a three-way directional valve 32. In this way, in the hollow chamber 34 formed on the upper surface of the casting sand S by closing the upper end opening of the flask 25 with the cover member 26, an on-off valve 29 is provided.
When the open high pressure liquid is supplied, the high pressure liquid is applied to the casting sand S, the vent plaque, the small hole 23 and the opening 21.
It penetrates in order and is discharged to the outside. In this case as well, as in the previous example, the high-pressure liquid flows through the casting sand S, so that the pressure of the liquid in the casting sand S has a pressure gradient in the height direction, so that each layer in the height direction in the casting sand S receives a force from the layer directly above it and a downward force according to the pressure gradient, and as a result, the casting sand S is densely packed and compressed. Next, after closing the on-off valve 29 to stop the supply of high-pressure liquid, the switching valve 32 is operated to supply compressed air to the hollow chamber 34, and the liquid that has permeated into the casting sand S by flowing through the casting sand S is removed. do. Thereafter, the residual compressed air in the hollow chamber 34 is discharged by operating the switching valve 32, the cover member 26 is removed, the flask 25 is raised, and the mold is removed to obtain a desired mold.

In the second embodiment, after high-pressure liquid is made to flow through the casting sand S, compressed air is made to flow through it to remove the permeated liquid from the mold.
If there is no problem with the remaining liquid, you may omit this step. Further, any liquid may be used, and a liquid to which a binder may be added may be used.

As is clear from the above description, the present invention is directed to a hollow part of a split model having a plurality of drainage holes or a space formed by a model plate having a plurality of drainage holes and a frame. A granular material such as metal powder or casting sand is introduced into the granular material, and a high-pressure liquid is supplied to the surface of the granular material to cause the liquid to flow through the granular material to drain the model or the model plate. Since this is a powder solidification method in which the powder is discharged through holes and thereby solidified, the high-pressure liquid flows through the powder and granules, thereby allowing the split model to be heated without causing vibration. It is possible to pack powder and granules at high density. Moreover, since the granular material is directly subjected to a downward force by the high-pressure liquid, excellent effects such as the ability to compress and solidify the granular material to a desired hardness even with a relatively low pressure are achieved.

[Brief explanation of the drawing]

The drawings show an apparatus for carrying out the method of the invention, FIG. 1 being a longitudinal sectional view of the first embodiment, FIG.
The figure is a longitudinal sectional view of the second embodiment. 3: Pore, 4: Lid member, 5: Frame, 23: Small hole, 24: Model plate, 25: Casting flask.

Claims (1)

[Claims] 1. Particles such as metal powder, casting sand, etc. are placed in the cavity of a split model with multiple drainage holes or in the space formed by the model plate with multiple drainage holes and the frame. and supplying high-pressure liquid to the surface of the granular material to cause the liquid to flow through the granular material and be discharged from the drain hole of the model plate, thereby solidifying the granular material. A method for solidifying powder and granular materials.