JPS6242698B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a model for a gas mold suitable for molding a mold using molding sand containing a gas-hardenable binder.

The applicant of the present invention recently discovered that after filling a model cavity with molding sand containing a gas-hardening binder, a negative pressure is applied from below the model to suck hardening gas into the molding sand. An application has been filed regarding a mold making method in which the foundry sand is hardened and molded by aeration. However, according to this method, in the case of a vertically long and narrow mold, there was a problem that the curing gas was difficult to pass through and the curing time took a long time.

The present invention has been made in view of these problems, and it is an object of the present invention to provide a model for a gas mold that can be easily hardened in a short period of time even if the mold is long and long.

The configuration of the present invention will be explained below based on examples.

1 is a matching model, and the matching model 1 is a pair of left molds 2
and a right mold 2a, a cavity 3 with an opening on the top surface is formed in the back of the left mold 2, and a cavity 3 communicating with the cavity 3 is formed in the cavity surface of the mold 2. A plurality of ventilation holes 4 are provided therein. Further, a hollow cavity 5 is formed in the back of the right mold 2a, and a plurality of ventilation holes 6 are formed in the cavity surface of the mold 2a to communicate with the cavity 5. At the same time, a conduit 7 communicating with the cavity 5 and having the other end connected to a vacuum pump (not shown) is connected to a lower portion of the back surface. Reference numeral 8 denotes a lid member having a gas supply hole 8a at its end, and the member 8 is placed on the upper surface of the model 1 so that the gas supply hole 8a communicates with the cavity 3 of the left mold 2. Reference numeral 9 denotes a flexible film having a hole 9a, and the film 9 is attached to the outer surface of the composite model 1 and the lid member 8 so that the hole 9a is connected to the gas supply hole 8a.
It is covered to match the . 10 is the combined model 1
It is an inverted U-shaped cap placed on the upper surface via a lid member 8 and a film 9, and the cap 10 is placed in communication with the cavity 3 through the hole 9a and the gas supply hole 8a. The cap 10 has a gas generator 11 connected to the inside of the cap 10.
are connected via a conduit 12. 13 is foundry sand containing a gas-hardening binder filled in the cavity portion 1a of the composite model 1.

Next, how to use the device configured as described above will be explained. The cavity portion of the composite model 1 is filled with molding sand 13, and then a lid member 8 is placed on the top surface of the composite model 1 to communicate the gas supply hole 8a to the cavity portion 3.
The molding sand 13 is placed on the molding sand 13, and the film 9 is placed on the outer surface of the combined model 1 and the lid member 8, as shown by the dashed line, and the gas supply hole 8a is inserted into the hole 9a.
In the state shown in Figure 1, which is covered in accordance with
A vacuum pump (not shown) connected in communication with conduit 7
When activated, hardening gas flows from the gas generator 11 through the conduit 12 into the cap 10, and then flows into the molding sand 13 in the cavity through the hole 9a, the gas supply hole 8a, the cavity 3, and the ventilation hole 4. It flows into the molding sand 13, passes through the vent 6, the cavity 5 and the conduit 7, and is absorbed and removed by a deodorizing device (not shown). Further, the film 9 is attracted to the outer surfaces of the mating model 1 and the lid member 8 as shown by the solid line by the suction force leaking from the gap between the mating surfaces.

In this way, when the hardening gas is passed through the molding sand 13 in the cavity for a predetermined period of time, the molding sand 13
3 is hardened and molded to a predetermined hardness. After curing, the cap 10 is removed and a vacuum pump (not shown) is operated to remove and clean the curing gas remaining in the molding sand 13. Thereafter, the composite model 1 is opened and the hardened mold is removed to complete the manufacturing operation.
Thereafter, repeat the above operation.

In short, since the present invention is as described above, even a long and narrow mold can be easily hardened in a short period of time, and it has excellent effects such as being useful for improving productivity, and has a significant effect on this type of industry.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention. 1: combined model, 3, 5: cavity, 4, 6: ventilation hole, 7: conduit.

Claims (1)

[Claims] 1. Forming a cavity in the back of a pair of left and right molds whose split surfaces are vertical so that the molds can be matched, and opening the upper end of one of the cavities,
A conduit that communicates with the cavity and connects to the vacuum device is provided at a lower position on the wall of the other cavity, and ventilation holes are provided in the left and right cavity surfaces to communicate with the cavity, respectively. a lid member that is placed on top of the matched model to close the opening at the upper end of the cavity of the model and to communicate a gas supply hole with the opening/closing opening at the upper end of the cavity;
A model for gas molding consisting of.