JPS5934459B2 - molding sand cooling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In the present invention, the sand forming the mold is removed from the casting,
This is related to the position where it is quickly cooled.

The sand that forms the mold reaches a high temperature when poured, and maintains a temperature of 100°C or higher even when the casting is taken out, so kneading and molding properties deteriorate at this temperature, causing the mold to deteriorate. This may lead to defects in the product and, in turn, to the product.

Therefore, after the casting is taken out and before the mold is formed again, the sand must be cooled down to 10°C or less above room temperature. To this end, various cooling devices are used as shown below. There is.

That is, (1) as shown in Fig. 1, a spiral feeding blade is provided inside a horizontally long cylinder to stir and push the sand, and at the same time air is blown into the cylinder to bring the sand and air into contact; This cools the sand.

(2) As shown in Figure 2, sand is supplied onto an air permeable belt conveyor and air is blown from below the belt conveyor.

■ As shown in Figure 3, stirring blades are installed above the belt conveyor that transports sand to stir the sand on the belt conveyor, thereby bringing the sand into contact with air and cooling it.

■ As shown in Figure 4, a punching plate is attached to a vibrating conveyor, and air penetrates from the bottom to the top when the sand is conveyed on the punching plate.

etc.

However, in either case, since the sand is cooled by making good contact with the air, the cooling time is long, and the equipment becomes extremely large and inconvenient.

The device of the present invention utilizes the latent heat of vaporization of water to shorten the cooling time and downsize the device, thereby eliminating the above-mentioned drawbacks.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The molding sand cooling device of the present invention will be described below with reference to the accompanying drawings showing one embodiment.

The device of the present invention has a hood 1 as shown in FIGS. 5 and 6.
a sand lifting device γ provided within the sand lifting device γ; an agitation device 10 and a projection device 11 provided spaced apart from each other within the sand lifting device γ; a conveying device 12 for supplying sand into the lifting device γ;
It consists of a moisture supply device 13 that supplies moisture to the sand fed on the conveying device 12.

The hood 1 is a box with a sand outlet 2 having a narrow width at the bottom.A window hole 3 through which the transport device 12 passes through and an air intake hole 4 are provided on one side wall of the box body, and a window hole 3 and an air intake hole 4 are provided on one side wall of the box body. A ventilation hole 5 communicating with a dust collector (not shown) is provided at the upper end to form an air supply device, and a belt conveyor 6 for transporting sand is provided directly below the sand outlet 2.

The sand lifting device γ has a window hole 8 of a predetermined size in the center of the mutually opposing circular side walls of a hollow cylindrical box provided horizontally.
is bored, and blades 9 of a length facing in the direction of centripetal force and not facing the window hole 8 are protruded from the cylindrical side wall at predetermined intervals,
Moreover, it is connected to an appropriate drive source (not shown) so that it is always rotated in one direction at a predetermined speed.

Both the agitation device 10 and the projection device 11 are made up of a plurality of blade plates projecting in a projecting shape, and are connected to a drive source (not shown) so that they can be rotated in the same direction as the sand lifting device T. The stirring device 10 is provided at a lower position toward the rotational force inside the sand lifting device γ (rightward in the case of clockwise rotation), and the projection device 11 is installed at a lower position toward the opposite side of the stirring device 10. It is being

The conveying device 12 is a belt conveyor, the terminal end of which is located directly above the stirring device 10, and a detection device (not shown) for detecting the weight, volume, temperature, etc. of sand is provided at a predetermined position of the conveying device 12. It is set up.

The moisture supply device 13 is similar to a shower, and automatically supplies moisture to the sand on the conveying device 12 in response to an output signal from the detection device (not shown).

The operation of the molding sand cooling device having the above structure is as follows.

After taking out the casting, the molding sand 14, which is at a high temperature of 100° C. or higher and forming the mold, is placed on the conveying device 12 and transported to the sand lifting device T, where a weight scale, sand height detector, and temperature sensor are used. A detection device (not shown) detects the weight, volume, temperature, etc. of the sand, and the moisture supply device 13 is operated in accordance with the output of the detection device to supply an appropriate amount of moisture to the molding sand 14. .

[It is preferable to supply approximately 3% (by weight) of water to the sand.

] The molding sand 14 containing an appropriate amount of water falls from the terminal end of the conveying device 12 onto the stirring device 10 as a sea lump;
The sand is scattered by the blades of the stirring device 10 and is evenly dropped onto the cylindrical side wall of the sand lifting device 1 without clumping in one place.

The sand lifting device 1 is always rotated in one direction,
Moreover, since the blades 9 are provided to protrude inward, the sand dropped onto the cylindrical side wall is lifted up to above the projection device 11 and then dropped toward the projection device 11.

When falling toward the projection device 11, the molding sand 14 becomes a lump, but the projection device 1 is constantly rotating.
The area of contact with the air that is scattered into the interior of the sand lifting device 1 by the blade plate 1 and headed for the dust collector from the air suction hole 4 through the ventilation hole 5 increases.

Therefore, the sand and air do not only spread over a wide area and exchange heat efficiently, but also promote the evaporation of the moisture supplied into the molding sand 14, and efficiently utilize the latent heat of evaporation of the moisture. It is possible to cool the molding sand 14 to below room temperature +10°C.

The molding sand 14 whose moisture has completely evaporated is lighter than the molding sand 14 containing water and has less adhesive strength.
The sand accumulates near the center of the sand lifting device γ (upper part in the drawing).
It overflows from the window holes 8, 8, falls into the hood 1, falls from the sand outlet 2 onto the belt conveyor 6, and is sent to the kneading section or the molding section (not shown) by the belt conveyor 6. The molding sand cooling device of the present invention as described above has the following effects.

■ Since the sand supplied with moisture is brought into contact with air, the sand not only exchanges heat with the air, but also cools the sand with the latent heat of vaporization of the moisture, so the cooling efficiency of the sand is significantly increased.

■ Since a projection device is installed in the sand lifting device, the sand is repeatedly lifted and scattered while moisture is attached, and is cooled in a short time by making good contact with the air.

■ Since the sand is repeatedly lifted and scattered within the sand lifting device, the device can be made smaller.

[Brief explanation of the drawing]

1 to 4 are simplified diagrams showing a conventional example, and FIG. 5 is a central vertical sectional side view showing an embodiment of the molding sand cooling device of the present invention.
FIG. 6 is a sectional view taken along line VI-VI in FIG. 1...Hood, I...Sand lifting device, 10...Agitation device, 11...Projection device, 12...Transportation device, 13. ...Moisture supply device.

Claims (1)

[Claims] 1. A box-shaped hood with a narrow sand outlet at the bottom, with a window hole and an air intake hole on one side wall, and an access hole on the other side wall, and a belt conveyor placed directly below the sand outlet. ,
Next, a window hole is bored in the center of the mutually opposing circular side walls of the cylindrical box, and at the same time, blades of a length facing in the direction of centripetal force and not facing the window hole are placed at predetermined intervals on the cylindrical inner wall. A protruding sand lifting device is rotatably installed horizontally in the hood, and a plurality of radially protruding blade plates are provided at the lower part of the sand lifting device, and the stirring device is rotatable by a drive source. 1. A molding sand cooling device characterized in that a projecting device is provided in parallel with a projecting device, and the tip of a transporting device provided with a moisture supply device is arranged so as to face inside the sand lifting device of the hood.