JPS6352979B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for compressing molding sand and molding a mold by applying pressure due to explosive combustion of a flammable gas mixture to the surface of molding sand filled in a flask.

As described above, in the method of molding a mold by compressing foundry sand using the pressure of an explosion, it is necessary to stabilize the combustion state of the flammable gas mixture and to increase the rate of combustion propagation. Therefore, stirring blades are installed in the cover member that defines an airtight hollow chamber on the surface of the molding sand into which the mixed gas is charged, to stir the mixed gas, stabilize the combustion state, and increase the combustion propagation speed. A mounted device has been proposed, but this device has the problem of a complicated structure.

The present invention has been made in view of the above circumstances, and is a mold making device equipped with a device that stabilizes the combustion state of a combustible mixed gas supplied into an airtight hollow chamber on the surface of molding sand and increases the combustion propagation speed. The purpose is to provide equipment. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Reference numeral 1 denotes a table installed via leg members (not shown). A model plate 2 is fixedly installed on the table 1, and a model part 3 of the model plate 2 is opened on the model plate 2 in the vertical direction. A taller flask 4 is placed with a seal member 5 interposed therebetween. 6 is a cover member for closing the upper end opening of the flask 4;
It is disposed directly above the flask so that it can be raised and lowered via a conventional means such as a downward cylinder (not shown), and is configured to airtightly close the upper end opening of the flask 4 via the seal member 8 when it is lowered. There is. and,
A box body 9 is fixed to the outer surface of the cover member 6 to form a flame chamber 10, and the flame chamber 10 communicates with the recess 7 through a small hole 11 transparently provided in the cover member 6. has been done. In addition, the box body 9 includes an igniter 12.
is inserted through the igniter 12, and a conducting wire 13 is provided at the base end of the igniter 12.
One end of the DC power supply 14 is connected via the
The other end of the DC power source 14 is connected to the box 9 via conductive wires 15, 16 and a switch 17, and when the switch 17 is turned on, the igniter 12 sparks within the flame chamber 10. In addition, the box body 9
A supply port 18 is provided in the wall of the
includes an on-off valve 19, a communication pipe 20, and a flow rate adjustment valve 2.
A compressed air source 22 is connected via 1;
The communication pipe 20 includes a branch pipe 23 and a flow rate adjustment valve 24.
A fuel cylinder 25 is connected thereto.

As shown in the figure, the structure configured in this way is as follows.
The molding sand S for green molding is filled into the flask 4 placed on the model plate 2, and the cover member 6 is lowered by the extension operation of a cylinder (not shown), so that the upper end opening of the flask 4 is sealed with a sealing member. 8 and the cover member 6, and a sealed space is defined on the surface of the molding sand S. And the flow rate regulating valves 21, 2
4 is appropriately adjusted and when the on-off valve 19 is opened, a mixed gas of fuel gas and air having a predetermined mixing ratio is supplied into the flame chamber 10 and the recess 7.

Under this condition, the on-off valve 19 is opened for a required period of time to supply a mixed gas of fuel gas and air into the flame chamber 10 and the recess 7, and the switch 17 is turned on to spark the igniter 12. Then, the fuel gas in the flame chamber 10 is combusted, and a flame is ejected from the small hole 11 into the recess 7. Due to the ejection of this flame, the fuel gas in the recess 7 is ignited reliably and stably, and combustion occurs. It spreads quickly and explodes and burns instantly, and as a result, the pressure within the recess 7 increases, compressing and hardening the foundry sand S. After the molding sand S has hardened, the cover member 6 is raised by a shortening operation of a cylinder (not shown), and then the hardened molding sand S is removed from the mold by raising the built-in molding flask 4, and is removed from another empty molding flask 4.
General molding operations such as placing the model on the model board 2 are performed, and one cycle is completed.

In the above embodiment, the flame chamber 10 is defined on the outer surface of the cover member 6, but it may be defined on the outer surface of the ceiling wall of the cover member 6 or within the recess 7. Further, although the table 1 is fixed and the cover member 6 is raised and lowered, the table 1 is raised and lowered and the cover part 6 is raised and lowered.
may be fixed. Furthermore, although the supply device for the mixed gas of fuel gas and air is connected to the box 9, it may be connected to the cover member 6 or to the box 9 and the cover member 6, respectively.

Furthermore, the air in the recess 7 may be used to burn the mixed gas, thereby omitting the blowing from the compressed air source 22. Further, the mixed gas may be any flammable mixed gas that causes explosive combustion.

As is clear from the above description, the present invention defines a flame chamber by fixing a box body equipped with an ignition means to a blast generating container having an explosion chamber, and a flame chamber is formed through a small hole. A supply device for flammable gas mixture is connected to at least one of the explosion chamber and the box, so that when the mixed gas in the flame chamber is ignited, flames are ejected from the small holes into the explosion chamber. Therefore, the mixed gas in the explosion chamber is reliably and stably ignited, and it explodes and burns at a high propagation speed. It has excellent effects such as improving stable ignition and combustion propagation speed.

[Brief explanation of the drawing]

The drawing is a partially sectional front view showing an embodiment of the present invention. 2: Model board, 6: Cover member, 7: Recess, 9:
Box body, 10: Flame chamber, 11: Small hole, 12: Igniter, 14: DC power supply, 22: Compressed air source, 25:
fuel cylinder.

Claims (1)

[Claims] 1. In a mold making device that compresses foundry sand by applying pressure due to explosive combustion of a flammable mixed gas to the surface of foundry sand, a blast generating container having an explosion chamber is
A box body equipped with an ignition means is fixed to define a flame chamber, and the flame chamber is communicated with the explosion chamber through a small hole, and at least one of the box body and the blast generating container is provided with a combustible material. A mold making device characterized in that a device for supplying reactive gas to the flame chamber and the explosion chamber is connected in communication.