JPS6113150Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a molding device for a core used in a mold.

Conventionally, when molding a core used in a mold, a method of filling molding sand by blowing or shunting has been adopted.

However, these methods rapidly blow a large amount of air into the model along with the foundry sand, which increases the pressure inside the model.The model used therefore needs to have a strong structure that can withstand this internal pressure. A large number of vent holes must be provided throughout the entire surface of the model to release internal pressure, making the structure of the model complex. Further, when molding a core with a complicated shape, the pocket and tip of the core are not sufficiently filled with molding sand, which often results in defective products.

This invention was made with the aim of improving this problem by providing a core molding device that can easily mold even complex-shaped cores, and making it possible to efficiently mold high-quality cores. be.

This invention will be described in detail below with reference to an illustrated embodiment. In the figure, 1 is the main body of this device, and a movable base 3 is mounted on the top of a box-shaped base 2 with one end pivoted to the front side of the base 2. A vibration table 5 is installed on this movable table 3 via an elastic support 4. A tilting cylinder 6 whose upper end is connected to the free end side of the movable base 3 is provided below the movable base 3, and the tilting cylinder 6 allows the movable base to
can be tilted upward about 30 degrees around the support shaft 7. Further, a plurality of dovetail grooves 5a are formed on the upper surface of the vibration table 5, and a model (not shown) can be attached to the dovetail grooves 5a. Vibrator 8 that vibrates 5 in the horizontal direction
However, vibrating machines 9 for vibrating the vibration table 5 in the vertical direction are attached to the left and right surfaces, respectively, so that the vibration table 5 can be vibrated in the vertical and horizontal directions.

On the other hand, a pillar 10 is erected from the rear upper surface of the base 2, and a sand hopper 11 is installed on the upper part of the pillar 10 so as to be located above the base 2.
A casting sand quantitative cutting hopper 12 is provided below the sand hopper 11.
The molding sand in the sand hopper 11 can be taken out in the required amount, and the molding sand taken out by the molding sand quantitative cutting hopper 12 is transferred to the funnel 13.
It is dropped into a model (not shown) on the vibration table 5 through the vibration table 5. In addition, reference numeral 14 in the figure is a fluid suction port that is connected to a suction port provided on the model to suck the air inside the model, or blows out air to make the foundry sand flow inside the model. It is connected to the direction switching valve 16. A pipe line 17 from a pressure reducing device (not shown) and a pipe line 18 from a blower (not shown) are connected to the direction switching valve 16, and air is sucked from the flow suction port 14 by a switching lever 19 provided on the front surface of the base 2. It is designed to allow air to be blown out. Note that 20 in the figure is a foot switch for operating the exciters 8 and 9.

For example, when molding the core 21 having the shape shown in FIG. While applying vibrations in the vertical and horizontal directions, the required amount of molding sand is dropped into the model from the molding sand quantitative cutting hopper 12. At the same time, the switching lever 19 switches the direction switching valve 16 to the suction side to suck the air inside the model, and
The movable base 3 is tilted at about 30 degrees by the tilting cylinder 6 so that the tip of the core 21 is lowered. As a result, the molding sand in the model was sufficiently filled up to the tip of the core 21, and a core 21 as shown in FIG. 2 without sand clogging defects was obtained.

By the way, when the model is modeled by applying only vertical and horizontal vibrations without suctioning the air inside the model, defects in sand clogging can be seen in the shaded area in Figure 3, as well as vertical and horizontal vibrations and a slope of about 30 degrees. When this was applied, some defects due to sand clogging were observed in the shaded area in Figure 4. From this, it is clear that the effect of simultaneously performing vertical and horizontal vibration, tilting, and suction is obvious.

Furthermore, when the packing density of the obtained core 21 was compared when the vibration direction and inclination were changed, the results shown in FIG. 5 were obtained. It can be seen from this figure that a core 21 with a higher packing density can be obtained by simultaneously applying vibration and inclination than by applying only vibration to the model. The frequency used in the above example was 1740 Hz, the suction pressure was 1600 Aq, and the suction amount was 4 m ² /mm.

As explained in detail above, this idea sucks the air inside while applying vibration to the model used to make the core.
At the same time, the model is tilted to fill the molding sand inside the model, so even if the core has a complex shape, it can be filled with enough molding sand all the way to the tip. can be easily obtained. Furthermore, since the pressure inside the model does not increase, there is no need for a model with a strong structure, which reduces the price of the model, and since there is no need to provide a large number of vent holes, the structure of the model can be simplified. Especially as cores for microwave curing molds.
Even if the mold is made using a model that has a coating layer, the coating layer will not be damaged, so a core with a smooth surface can be easily obtained.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention; Fig. 1 is an overall view, Fig. 2, Fig. 3, and Fig. 4 are explanatory diagrams of cores molded by different means, and Fig. 5 is an illustration of molding conditions and packing density. It is a bar graph showing the relationship between. 2 is a base, 3 is a movable table, 4 is an elastic support, 5 is a vibration table, 6 is a tilting cylinder, 8 and 9 are exciters, 11 is a sand hopper, and 12 is a hopper for cutting out a fixed quantity of molding sand.

Claims (1)

[Scope of utility model registration request] A movable base 3 is located on the top of the base 2 and can be tilted at any angle by a tilting cylinder 6, and a movable base 3 is mounted on the movable base 3 via an elastic support 4 and can be moved up and down by vibrators 8 and 9. , a vibration table 5 which is vibrated in the left and right directions and a model can be attached to the top surface.
, a sand hopper 11 and a hopper 12 for supplying molding sand into the model, which are located above the vibrating table 5, and a hopper 12 for cutting out a quantity of molding sand, and a suction means for sucking air inside the model from a suction port provided in the model. A core molding device equipped with: