JPH0890160A - Vibrating method of vibrating table for filling molding sand - Google Patents

Abstract

PURPOSE: To secure the sufficient filling density of molding sand in a hole even in the case of forming the hole in the X-axial direction in a lost foam pattern or a self-curing mold, in the molding of the lost foam pattern casting or the self-curing mold. CONSTITUTION: A table 3 is arranged to be freely vibrated on a machine base through springs, and two sets of vibrating motors 4, 4 or 4', 4' having a horizontal axis in the lower part or the side surface of this table 3 and rotating in the same direction are fitted. A molding flask placed and fixed on the table 3 is simultaneously vibrated in two directions of the vertical direction (Z-axis) and the horizontal direction (X-axis) by rotating two vibrating motors which are properly selected so that their unbalanced wt. are synchronized with each other mechanically or electrically.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to the disappearance model casting or the self-hardening mold making in one horizontal direction or two horizontal directions.
The present invention relates to a method of vibrating a vibration table for filling foundry sand, which can secure a sufficient sand packing density in these holes even if holes are formed in the axial direction.

[0002]

2. Description of the Related Art The vanishing model casting method can be said to be an excellent casting method which has many advantages over conventional casting methods. However, in order to obtain high-quality cast products, the vanishing model made of foamed products placed in the flask should not be deformed, and the hollow part of the vanishing model should be filled with molding sand and disappeared when the molten metal is poured. It is required that the molding sand be filled with the air permeability that allows the generated gas to escape sufficiently with a strength that does not cause wall movement of the model.

Therefore, conventionally, the molding sand is filled by placing and fixing the molding frame on the vibration table and vibrating the vibration table and the molding frame. That is, as shown in FIGS. 4 and 5. A table 3 is arranged horizontally and swingably on a machine base 1 via springs 2 and, and two vibration motors 4 and 4 having a horizontal axis parallel to the Y axis are attached to the lower surface of the table 3. By rotating the vibration motors 4 and 4 in mutually opposite directions to vibrate the table 3 and the casting frame 5 mounted and fixed on the table 3 in the Z-axis direction, the periphery of the vanishing model 6 is filled with the foundry sand 7. Vibrating device configured as described above. Alternatively, as shown in FIGS. 6 and 7, in addition to the vibrating device, two vibrating motors 8 having a vertical axis parallel to the Z axis are additionally fixed to both sides of the table 3, and the vibrating motors are attached. 8 and 8 are rotated in opposite directions to vibrate the table 3 and the casting frame 5 in two directions of the Z-axis direction and the X-axis direction, so that the periphery of the vanishing model 6 is filled with the foundry sand 7. A vibrating device is used.

However, in the conventional vibration device described above, when the vanishing model 6 has holes in the horizontal 1-axis direction or the horizontal 2-axis direction, it is possible to secure a sufficient sand packing density in these holes. It has the drawback that it cannot. This can be confirmed by the following experiment by the present inventor.
The filling experiment was performed using the experimental apparatus shown in FIG. That is, the experimental device has a side length W of 300 m.
The test piece 9 is installed inside the flask 5 having a height m and a height H of 400 mm, and the periphery thereof is filled with the molding sand 7. The test piece 9 is made of a transparent acrylic resin and has a main tube portion 9A having a uniform inner diameter (d1 = 25 mmφ) and a main tube portion 9A.
Having an axis C2 that is orthogonal to the axis C1 of the main branch 9A and having a uniform inner diameter (d2 = 15 mmφ) and a length (L
= 90 mm), the axial line C1 of the main pipe portion 9A is oriented vertically, and the branch pipe portion 9B
The axis C2 of B from the top surface 7A of the foundry sand 7 to a predetermined depth (D
= 225 mm) and the upper end of the main pipe portion 9A is projected from the top surface 7A of the molding sand 7. Table 1 shows the measurement results when such an experimental apparatus is mounted and fixed on the table 3 of the first conventional example by the conventional standard type vibration apparatus as shown in FIGS. 4 and 5, and the vibration time is set to 30 seconds. Shown in
Further, the same experimental device is mounted and fixed on the table 3 of the second conventional example by a vibration device in which two vibration motors 8 and 8 are additionally fixed to the first conventional example as shown in FIGS. Table 2 shows the measurement results when fixed at 30 seconds.

[0005]

[0006]

In the conventional vibration device corresponding to Table 1, it was confirmed that the casting sand 7 did not flow in the X-axis direction. This means that when the disappearance model 6 has a hole in the X-axis direction,
It shows that it is not possible to secure a sufficient sand packing density in this hole. Further, it is shown that even the conventional vibration device corresponding to Table 2 cannot expect the inflow amount of sand in the X-axis direction.

[0008]

The problem to be solved by the present invention is that when a vanishing model has a hole in the X-axis direction, the state of sand inflow into this hole is poor, and it is sufficient in the hole. That is, it is impossible to secure a high packing density of molding sand.

[0009]

SUMMARY OF THE INVENTION According to the present invention, a casting sand filling table having a casting frame detachably fixed to the upper surface thereof is disposed on a machine base so as to be swingable via a spring, and Two vibration motors that project downward or to the side and have parallel horizontal axes and that rotate in the same direction are mechanically synchronized by a belt or the like, or the action of an electrical signal The unbalanced weights of the two vibration motors are rotated in the same phase in synchronization with each other. Even if the vanishing model has holes in the X-axis direction, the filling density of the foundry sand is sufficient. In addition to the above, the purpose of ensuring a uniform filling density of the foundry sand at each position in the flask was achieved.

[0010]

[Operation] According to the present invention, the unbalanced weights of the two vibration motors, which are respectively attached to the lower portion or the lateral side of the table, are rotated in synchronization with each other, so that the table moves vertically and horizontally in one direction ( For example, even if the vanishing model has a hole in the X-axis direction formed by vibrating simultaneously in two directions (for example, the X-axis direction), a sufficient filling density of the foundry sand can be secured in this hole, It is possible to secure a uniform packing density of foundry sand at each position.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a front view of the present invention, and FIG. 2 is a plan view of FIG. It should be noted that the same or corresponding portions as those of the conventional example will be described by attaching the same reference numerals. In FIG. 1 and FIG. 2, a table 3 is arranged on a machine base 1 via springs 2 and 2 so as to be swingable horizontally, and each table 2 has a horizontal axis parallel to the Y-axis at the bottom or side thereof. The vibration motors 4, 4 or 4 ', 4'of the table are attached, and when these vibration motors 4, 4 or 4', 4'are mechanically synchronized, they are connected and rotated by timing belts 9, 9 ', etc. . In the case of electrical synchronization, the phase difference detecting devices 10 and 10 'detect the phase difference of the unbalanced weights of the vibration motors and send the signals to the phase difference controlling devices 11 and 11'. Further vibration motors 4, 4 or 4 ',
A synchronizing signal is sent to 4'to synchronize the vibration motors 4, 4 or 4 ', 4'. The casting sand 5 is placed and fixed on the table 3 and is filled with casting sand 7. The vanishing model 6 is installed inside the casting sand 7. In such a configuration, the vibration motors 4 and 4 that are appropriately selected
Alternatively, when 4 ′ and 4 ′ are synchronously continuously rotated in the same direction for a certain period of time, the table 3 and the flask 5 mounted and fixed on the table 3 are moved in the vertical direction (Z axis) and the horizontal 1 direction (X axis). Two
Vibrate simultaneously in the directions.

As an experimental example, the experimental apparatus shown in FIG. 8 is mounted and fixed on the table 3 shown in FIGS. 1 and 2, and the rotation direction of the vibration motors 4, 4 or 4 ', 4'is limited to a fixed direction. Table 3 shows the measurement results when the vibration time was set to 30 seconds.
Shown in

[0013]

In Table 3, it was confirmed that the height of inflow in the X-axis direction was significantly increased as compared with the measurement result of the first conventional example (Table 1). This proves that even if the vanishing model has holes in the X-axis direction, it is possible to secure a sufficient packing density of the molding sand 7 in the holes.

Incidentally, in the above-mentioned embodiments, description is made by applying to the filling of molding sand in vanishing model casting.
Even when the present invention is applied to the molding of a self-hardening mold, the same action and effect as those of the above-mentioned embodiment can be obtained.

[0016]

As described above, according to the present invention, two vibration motors which are attached to the lower part or the side of the table with a horizontal axis parallel to each other and which are appropriately selected are mechanically connected by a belt or the like. Or by the action of an electrical signal 2
By rotating the unbalanced weights of the table vibration motors in the same phase, the table vibrates simultaneously in two directions, vertical and horizontal, and the vertical and horizontal vibration forces become equal. Even if a horizontal uniaxial hole is formed in the self-hardening mold, a sufficient filling density of the molding sand can be secured in this hole.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a plan view showing a second embodiment of the present invention.

FIG. 4 is a front view showing a first conventional example.

FIG. 5 is a plan view of FIG.

FIG. 6 is a front view showing a second conventional example.

FIG. 7 is a plan view of FIG.

FIG. 8 is a perspective view of an experimental device.

[Explanation of symbols]

 1 Machine Stand 2 Spring 3 Table 4, 4'Vibration Motor 5 Casting Frame 6 Disappearance Model 7 Foundry Sand 8 Vibration Motor 9, 9'Timing Belt 10, 10 'Phase Difference Detector 11, 11' Phase Difference Controller

Claims (2)

[Claims] 1. A casting sand filling table, to which a casting frame is detachably fixed on the upper surface, is swingably arranged on a machine base via a spring, and is projected parallel to the lower portion or side of the table. Attaching two vibration motors that have a horizontal axis and that rotate in the same direction are mechanically synchronized by a belt or the like, and rotate the unbalance weights of the two vibration motors in the same phase. A vibration method for a vibration table for filling foundry sand. 2. A molding sand filling table having a molding frame detachably fixed to the upper surface thereof is swingably arranged on a machine base via a spring, and the molding sand filling table extends parallel to the lower portion or side of the table. The phase difference detection device detects the phase difference between the unbalanced weights of the two vibration motors that are attached with a horizontal axis and rotate in the same direction, and this is electrically synchronized by the phase difference control device. A method of vibrating a vibrating table for filling foundry sand, which is controlled and rotated in the same phase.