JPS5834223B2 - Method and equipment for filling molten metal in vertical die casting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for filling molten metal in vertical die casting.

The relationship between the upper die g and the lower die of a conventional vertical die casting machine is as follows:
For example, as shown in Fig. 1, in the method of pouring molten metal into the upper sleeve f using that device, a counter plunger is used to prevent the poured molten metal a from directly flowing into the cavity b. The runner d is sealed with the tip C, and the counter plunger tip C is lowered in accordance with the movement of the upper plunger e to fill the cavity b with the molten metal a.

Therefore, the molten metal a falls freely during the operating stroke of the counter plunger tip C.

Therefore, the freely falling molten metal a flows into the cavity b through the runner d while scattering.

At that time, if the molten metal that is pressurized by the upper plunger e and flows in later is too slow, the droplets and molten metal that flowed in earlier will solidify and be unable to fuse with the molten metal that flows in later, resulting in formation of molten metal. This would be undesirable.

Furthermore, if the movement of the upper plunger e is made faster relative to the movement of the counter plunger tip C, pressure is applied to the molten metal a by the upper plunger e before the tip C leaves the upper sleeve f. A situation arises.

In such a case, the area through which the molten metal a passes increases continuously and is ejected at high speed, so that the initial molten metal droplets flow into the cavity b and solidify.

Therefore, it becomes impossible to fully fuse with the molten metal that has flowed in later, resulting in a molten metal boundary.

As described above, in vertical die casting using the counter plunger type, it is unavoidable that turbulence of the molten metal occurs due to the operating timing and operating stroke of the counter plunger, and casting defects such as hot spots in the product are likely to occur. Become.

The present invention eliminates the above-mentioned drawbacks of the conventional ones, and
In other words, it is possible to prevent the scattering and advance phenomenon of molten metal passing through a runner etc. and the discontinuous phenomenon of flow when the molten metal is heated. For an example thereof, see FIGS. 2 and 3. I will explain.

FIG. 2 is a longitudinal sectional elevational view showing the state in which molten metal is poured into the sleeve by the method of the present invention, and FIG. 3 is a longitudinal sectional elevational view showing the state after the molten metal is poured.

In Figures 2 and 3, 1 is the upper mold, 2 is the lower mold, and 3
is an upper sleeve, and pouring is performed from pouring port 4.

At this time, the lower sleeve 5 rises and the upper end of the sleeve 5 comes into contact with the lower end of the upper sleeve 3, so that the molten metal poured into the sleeve flows through the runner 10 and the lower end of the upper sleeve 3, as shown in FIG. There is no access to cavity 9.

A counter core 6 is fixed to the lower mold 2, serves as a guide shaft when the lower sleeve 5 slides up and down, and has a post-pressing tip 7 built therein so as to be movable up and down.

The upper surface of this chip 7 is flush with the upper end surface of the counter core 6 located below the parting surface of the mold,
The upper plunger tip 8 descends and fills with molten metal, and when the oil pressure of the hydraulic cylinder 11 that moves the tip 8 reaches a set value or more, or after a certain period of time, the upper plunger tip 8 is moved upward by the hydraulic cylinder 13 and fills with molten metal. This allows you to do more.

The lower sleeve 5 is moved up and down by a hydraulic cylinder 12.

As the upper plunger tip 8 moves, it is actuated downward by the signal from the limit switch 14, and the molten metal flows into the runner 10.
and the cavity 9 is filled.

Furthermore, to explain the filling method of the present invention, a lower sleeve 5 that is vertically slidable is attached to the lower end of the upper sleeve 3, which is provided at a position where the lower end almost coincides with the parting surfaces of both the upper and lower molds 1 and 2. The runner 10 to the cavity 9 is brought into contact with the upper end of the
is placed in a closed state, and the fixed counter core 6 whose upper end is located below the parting surface of both the upper and lower molds 1 and 2 and which has a built-in post-pressurizing tip 7 that can be slid up and down. Molten metal is poured into the upper sleeve 3 with the upper surface of the post-pressurizing tip 7 substantially aligned with the upper end.

This situation is just shown in FIG.

Next, the upper plunger tip 8 is appropriately lowered, the lower sleeve 5 is lowered to open the runner 10, and the cavity 9 is filled with molten metal, and finally, the post-pressurizing tip 7 is raised. The above-mentioned light test ends.

This situation is just shown in FIG.

As described above, according to the molten metal filling method of the present invention, the position of the poured molten metal in the sleeve does not change until it reaches the runner into the cavity, and the amount of descent of the lower sleeve is smaller than that of the conventional counter. than the amount of descent of the plunger tip.
Since the number of molten metals is much smaller, there is no scattering or advance phenomenon of the molten metal passing through the runner when the runner is open, and discontinuous flow phenomenon can also be avoided. Casting defects such as melting holes caused by the lowering of the jar tip are significantly reduced, and in addition, the filling is completed by raising the post-pressurizing tip located below the parting surface of the mold, which improves solidification. The amount of shrinkage can be adequately replenished.

Furthermore, the apparatus of the present invention has a simple structure and can reliably carry out the filling method of the present invention.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional elevational view showing an example of a conventional vertical die-casting device, Fig. 2 is a longitudinal sectional elevational view showing an embodiment of the present invention in a state in which molten metal is poured, and Fig. 3 is a molten metal light beam. It is a longitudinal sectional elevation view showing the rear state. 1... Upper mold, 2... Lower mold, 3... Upper sleeve, 4
...Pouring spout, 5...Lower sleeve, 6...Counter core, 7...Post-pressurizing tip, 8...Upper plunger tip, 9...Cavity, 10...Run runner , 11
, 12, 13... Hydraulic cylinder 14... Limit switch.

Claims (1)

[Scope of Claims] 1. The upper end of the lower sleeve, which is slidable up and down, is brought into contact with the lower end of the upper sleeve, which is provided at a position where the lower end almost coincides with the parting surface of the mold, to supply hot water to the cavity. At the same time, the upper end of a fixed counter core, the upper end of which is located below the parting surface of the mold and has a built-in post-pressing chip that can be slid up and down, is placed. The molten metal is poured into the upper sleeve with the upper surfaces of the post-pressurized tips almost aligned, and then the upper plunger tip is lowered appropriately and the lower sleeve is lowered to open the runner. filling the cavity with the molten metal;
Finally, the method for filling molten metal in a vertical die-casting device is characterized in that the post-pressurizing tip is raised to finish the process. 2. An upper sleeve whose lower end is provided at a position that almost coincides with the parting surface of the mold, an upper plunger tip that presses the molten metal in the upper sleeve from above, and an upper plunger tip that is located below the upper sleeve and that pushes the molten metal into the cavity. A lower sleeve that can be slid up and down to open and close the runner, a fixed counter core that is installed so that its upper end is below the parting surface of the mold, and a built-in 1. A vertical die-casting device, characterized in that it is equipped with a post-pressurizing tip that is provided so as to be slidable up and down.