JPS626894B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molding sand supply device suitable for filling a model box with molding sand.

Generally, molding sand is filled into the model box by the blowing method, but in order to prevent the model box from being opened by blowing pressure, a clamping device is required, and the model box itself is Since the model box had to be able to withstand blowing pressure, it was difficult to make the model box using a wooden mold.

The present invention has been made in view of these problems, and does not require a clamping device for the model box.
Moreover, it is an object of the present invention to provide a molding sand supply device that can be used satisfactorily even in a wooden model box.

The configuration of the present invention will be explained below based on the embodiment shown in FIG.

Reference numeral 1 denotes a model box with a concave cavity 2 on the top surface, and on the top surface of the model box 1, a trapezoidal cross section is formed between the inner walls of the bottom, and a ventilation groove serving as an air passage is provided in the center. Hollow crosspiece members 4 with holes 3 are installed vertically and horizontally at approximately equal intervals, and each ventilation groove is connected to the other, and a vent plug (Fig. A sand supply box 6 is provided with a plurality of ventilation holes 5 (not shown) in which the ventilation holes 5 and the tapered sand supply holes 7 formed between the opposing walls of the crosspiece member 4 are communicated with the cavity part 2, respectively. It is placed there. Further, a vacuum pump 8 is connected to the wall surface of the sand supply box 6 through a pipe 9, an on-off valve 10, and a tank 11 so as to communicate with the ventilation groove 3. 12 is foundry sand stored in the sand supply box 6.

Next, the operating state will be explained. In the state shown in FIG. 1, after closing the on-off valve 10 and operating the vacuum pump 8 to reduce the pressure inside the tank 11, the on-off valve 10
When opened, the cavity 2 is made negative pressure through the ventilation groove 3 and the ventilation hole 5, and the molding sand 12 in the sand supply box 6 is released.
is sucked and filled into the cavity 2 through the sand supply hole 7. At this time, since negative pressure is applied to the inside of the cavity 2 from above, the upper part of the cavity 2 is also well clogged with sand, so that the molding sand is evenly filled in the upper and lower parts. A mold with uniform hardness can be obtained.

Next, another embodiment of the present invention will be described based on FIG.

Components having the same configuration as those of the embodiment shown in FIG.

Reference numeral 13 denotes a model stand that is equipped with a decompression chamber 14 inside and has a ventilation hole 15 in its upper surface to communicate with the decompression chamber 14. On the upper surface of the model table 13, there is a cavity portion that is formed vertically and penetrated through the molds. A vertically divided model box 17 having a cavity 16 formed therein is placed with the cavity 16 communicating with the ventilation hole 15.

Further, on the upper surface of the model box 17, a sand supply box 6 containing foundry sand 12 is placed with the sand supply hole 7 and the ventilation hole 5 communicating with the cavity portion 16. Further, on the wall surface of the model stand 13, one end of a pipe 18 connected in the middle of the pipe 9, which communicates with the decompression chamber 14 and whose other end connects between the on-off valve 10 and the tank 11, connects an on-off valve 19. It is connected through.

Next, the operation of the embodiment shown in FIG. 2 will be explained. In the state shown in FIG. 2, the on-off valves 10 and 19
When the on-off valves 10 and 19 are opened after the vacuum pump 8 is operated to reduce the pressure inside the tank 11, the inside of the cavity 16 is opened from above through the ventilation groove 3 and the ventilation hole 5, and the depressurization chamber is opened. 14. Negative pressure is applied from below through the ventilation holes 15, so
The cavity 16 is made to have a negative pressure, and the molding sand in the sand supply box 6 is sucked and filled into the cavity 16 from the sand supply hole 7 . At this time, negative pressure will be applied to the cavity 16 from above and below, so even if the model has a shape that makes it difficult to clog the upper and lower parts with sand, the upper and lower parts will be sufficiently filled with sand. .

In short, the present invention provides hollow crosspiece members with openings on the top surface and ventilation grooves that serve as air passages between the inner wall surfaces of the bottom portions, which are installed at approximately equal intervals, and each ventilation groove is provided in communication with each other. In addition, the sand supply box has a ventilation hole in its lower surface that communicates with the ventilation groove, and an on-off valve, a tank, and a vacuum pump are sequentially connected to the wall of the sand supply box, which communicates with the ventilation groove, so that the upper part of the cavity is connected to the sand supply box. Therefore, the molding sand is uniformly filled in the upper and lower parts of the cavity, and a good mold can be expected.Moreover, there is no need for a clamping device for the model box, and even a wooden model box can be used. It has various excellent effects such as being fully usable, and its effects on this type of industry are significant.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the invention, and FIG. 2 is a sectional view showing another embodiment of the invention. 3: Ventilation groove, 4: Cross member, 5: Ventilation hole, 6: Sand supply box, 8: Vacuum pump, 10: Open/close valve, 11:
tank.

Claims (1)

[Claims] 1 Hollow crosspiece members with openings on the top surface and with ventilation grooves for air passages are installed at approximately equal intervals between the inner walls of the bottom, with each ventilation groove communicating with the other. A foundry sand supply device characterized in that an on-off valve, a tank, and a vacuum pump are sequentially connected to a wall of a sand supply box having a ventilation hole in communication with the ventilation groove. .