JPS60154860A - Low-pressure multi-casting method - Google Patents

Abstract

PURPOSE:To obtain many castings with one casting machine by pouring a molten metal into cavities through the respective sprue pipes corresponding to the number of the cavities, sealing the molten metal by rotation or linear movement of the sprue pipes and retaining the pressure by using the liners provided to the wall surfaces of dies. CONSTITUTION:Sprue pipes 11 of the number corresponding to the number of cavities are connected to forming dies 1, 2 and after a molten metal 12 is poured into the dies 1, 2 through the pouring holes 13 of the pipes 11, the pipes 11 are rotated 90 deg. to seal the molten metal 12 in the dies 1, 2. The horizontal liner 3 and drag liner 4 disposed to the wall surfaces of the dies 1, 2 are pressed to retain the pressure of the molten metal 12. Water is passed through cooling holes 8 in order to solidify the molten metal 12 packed in a gate 7 then the solidified castings are removed from the dies 1, 2 by ejector pins 10 after the pipes 11 are separated. The many castings are thus cast with the less number of the casting machine.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a multi-low pressure casting method with excellent strip production efficiency.

(Prior art) In the conventional low-pressure casting method, a relatively small pressure (o, o5 ~ [1.8 kg/
α2) is added to the gas body, the molten metal is pushed up through the hot water supply pipe in the opposite direction to gravity, and the molten metal is poured into a mold that is placed in close contact with the hot water supply pipe, after which it is maintained at a predetermined pressure for a certain period of time, e.g. about 4 to 6 minutes. After applying pressure and ensuring solidification time, it is evacuated and the molten metal from the annulus is returned.

After cooling, the solidified product was demolded.

When performing low-pressure casting using such a process, one low-pressure casting machine is required for one mold, as the crucible and mold are connected to the molten metal in multiple ways. Unless the previous shot is demolded, the primary work cannot be performed. Therefore, manufacturing many types of cast products requires a large number of equipment, which requires a huge investment in equipment. Another problem was that the work efficiency was low, resulting in low productivity and the need for a large number of workers.

(Objective of the Invention) The present invention is intended to solve the above-mentioned problems in the prior art, and its purpose is to be able to manufacture many types of cast products with a small number of casting machines, and to improve work efficiency. The objective is to provide a multi-low pressure casting method.

(Structure of the Invention) In other words, 1. The multi-low pressure casting method of the present invention includes a connecting step of connecting a sprue pipe having a number of holes for injecting molten metal corresponding to the number of cavities of the mold to the mold, and a step of connecting the sprue pipe to the mold. a pouring process of injecting the molten metal into the mold through the hole in the pipe; a sealing process of rotating or linearly moving the sprue pipe to seal the molten metal in the mold; and a molten metal sealed in the mold. a pressure holding step in which the metal is pressed by a suppressing means such as a nest placed on the wall surface of the mold; a weir cooling step in which the molten metal in the ring between the mold and the joint is cooled and solidified; It is characterized by comprising a separation step of separating the sprue pipe, and a demolding step of taking out the cooled and solidified cast product from the mold.

The sprue pipe is manufactured using a material that is stable against the molten metal, such as various ceramics, so as to have the necessary strength.

The size and shape are optimally selected depending on the type of e-4j product, but usually a cylindrical shape with one end closed is used.

A hole having a desired size and shape is bored in the side or bottom surface of the sprue pipe, taking into account the amount and speed of injection of the molten metal.

The number and position of holes are determined by considering the number of cavities communicating with the joint, the strength of the sprue pipe, etc. Molten metal is injected into the mold containing the core, if desired, through the holes of the sprue pipe. In order to seal the molten metal in the mold, K rotates the sprue pipe by a predetermined angle or moves it linearly, for example, up and down, so that the entrance of the molten metal into the mold is blocked by the sprue pipe wall surface. On the other hand, the above-mentioned sealing steps may be performed simultaneously or sequentially.

Next, in order to make the molten metal in the mold healthy, appropriate pressure is applied to the feeder by means of restraints such as mannequins placed at predetermined positions on the mold wall. The molten metal filled in the ring part between the molds is cooled and solidified by cooling with water, oil, air, nitrogen, etc. through cooling holes provided inside the mold, and the body is heated to 6tE.Then, the sprue pipe is removed from the joint. Separate and further cool the mold to take out the solidified cast product and core from the mold. .

(Example) The present invention will be explained in further detail by the following example. Note that the present invention is not limited to the following examples.

FIG. 1 is a sectional view showing the state of the mold waiting for casting before the sprue pipe is connected. In the figure, 1 is an upper molding die, 2 is a lower molding die, and 3 is a side insert.

4 is a lower mold insert, 5 is a core, 6 is a lower mold insert cylinder, 7 is a weir, 8 is a cooling hole, and 9 is a sprue pipe joint.

10 indicates an ejector turbine. 1 for the horizontal insert 3 and the lower mold insert 4: in the retreated position.

FIG. 2 is a cross-sectional view showing the casting state, in which molten metal 12 is filled into the mold through the sprue pipe 11 connected to the sprue joint part 9.

The third picture 1 is a cross-sectional view showing the new process. After filling with molten metal, the inlet pipe 11 is rotated 90 degrees, the position of the pouring hole 13 is changed, and the weir 7 is covered with the wall of the sprue pipe 11.

Furthermore, a horizontal insert 3 is used to press the molten metal sealed inside the mold.
and shows the state in which the lower mold insert 4 has slid. At this time weir 7
7' (Water or air is flowed through the cooling holes 8 to accelerate the solidification of the molten metal.

Also, the melt inside the sprue pipe 11 @12? −j, crucible or f:i
It has returned to the holding furnace (not shown) side.

pP, Figure 4 is a cross-sectional view showing the state where the sprue pipe 10 is separated from the joint 9. At this time, the molten metal in the weir 7 is solidified, but the product part in the mold is not completely solidified. .

Next, the mold is moved to a solidification station, held for a certain period of time to completely solidify, and then moved to a demolding station.
Remove the product. After demolding, move the mold to the core storage station.

After the core is placed in the mold, it is returned to the casting station and the process returns to the beginning.

Figure 5 shows an outline of the casting process.

FIG. 6 is a sectional view of the sprue pipe in FIG. 3 viewed from direction A in the figure, and the two pouring holes 13 are arranged symmetrically with respect to the center.

FIG. 7 is a cross-sectional view showing the pouring process in an embodiment in which a sprue pipe having another shape is used. In this case, the sprue pipe has two pouring holes at the bottom. .

FIG. 8 is a cross-sectional view showing the sealing process of yet another embodiment, in which the molten metal is sealed by moving the sprue pipe linearly (moving vertically in the figure).

<Effects of the Invention> As mentioned above, the multi-low-pressure casting method of the present invention seals the molten metal in the mold by rotating or linearly moving the sprue pipe, and maintains the pressure by a nest etc. arranged on the wall of the mold. Because it is a thing, 1
Multiple molds can be used for one low-pressure casting machine, reducing the number of casting machines required. In addition, the number of manpower required can be reduced accordingly.4 Furthermore, unlike conventional methods, work such as pouring into other molds can be performed continuously during the solidification time of the cast product in one mold. Therefore, the production efficiency is improved, and the production capacity with the same number of casting machines is greatly improved compared to the conventional method.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the state of a mold waiting for casting in an embodiment of the method of the present invention. FIG. 2 is a sectional view showing the pouring process. FIG. 3 is a sectional view showing the same sealing process. FIG. 4 is a cross-sectional view showing the sprue pipe separated, and FIG. 5 is a schematic diagram of the casting process of the method of the present invention. FIG. 6 is a sectional view of the sprue pipe in FIG. 3, viewed from direction A in the figure. FIG. 7 is a sectional view showing the pouring process of another embodiment. Figure @8 is a sectional view showing the sealing process of yet another embodiment. In the figure, 1, 1', 1'...upper mold mold 2, 2', 2
'... Lower mold mold 3... Side insert 4... Lower insert 5... Core 6... Lower insert cylinder 7... Weir 8... Cooling hole 9... Sprue pipe joint 10... Ejector 11. 11', 11'... Sprue pipe 12... Molten metal 1
3... Pouring hole patent applicant Toyota Motor Corporation, j・ 1 +='! :','21ko,-'knee3 7. IJ :i"41.'-J7;, :p 5 1-)j 多kJmi、Isu width goi・inside (1 3 7/

Claims (1)

[Claims] A connecting step of connecting a sprue pipe having holes for injecting molten metal in a number corresponding to the number of cavities of the mold to the mold, and a pouring step of injecting the molten metal into the mold through the holes of the sprue pipe. a sealing step of rotating or linearly moving the sprue pipe to seal the molten metal in the mold; and a sealing step of sealing the molten metal in the mold by suppressing means such as a nest placed on the wall of the mold. a holding pressure step for suppressing, a collecting section cooling step for cooling and solidifying the molten metal in the collecting section between the mold and the joint section, a separation step for separating the molten metal from the joint section, and a cooling and solidifying step for separating the melt from the joint section. A multi-low pressure casting method characterized by comprising a demolding step of ejecting the cast product from the mold.