JPS6011589B2 - Vertical die casting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The disclosed technology belongs to a technology that can ensure complete integrity in the process of filling molten metal in vertical die casting.

Therefore, this invention is a vertical die-casting bag,
Relating to a vertical die-casting device in which molten metal is poured into a sleeve with a gate closed, and then the gate is opened and molten metal is filled into a cavity from a moat through the cooperative action of a pressurized plunger and a counter plunger. In particular, in the lowering process of the pressurized plunger after supplying V, the lower mold sleeve corresponding to the upper mold sleeve is lowered by the lifting device to open the gate, and the molten metal flows through the lagoon by its own weight into the cavity. After the predetermined amount is filled, the pressure plunger and counter plunger work together to fill the cavity with molten metal in two stages at a predetermined distance, and the runner is placed inside the cavity in order to increase the gravity filling rate at the initial stage of casting. This invention relates to a vertical die-casting device formed in an obliquely tapered shape.

<Prior art> As is well known, die-casting is widely used in various castings due to its precision and other advantages, but among these, vertical die-casting equipment is widely used due to its small amount of gas entrainment. It has been adopted.

As shown in Fig. 1, the vertical die casting equipment that has been commonly used up until now has an upper die 1 and a lower die 2.
In many cases, a runner 4 is connected to a cavity 3 formed by fastening, and a sprue 6 is formed by a sleeve 5 forming the runner 4, and a counter plunger 7 is set so as to close a gate 9 with a counter sill 8. and molten metal 1
0 is supplied, and in this state, the pressurizing plunger 12 is pressed down by the pressurizing cylinder 11, and the counter plunger 7 is lowered by working with the counter cylinder 8, and the molten metal 10 is poured from the opened runner 4 into the cavity 3. I try to fill it inside. In this case, it is desirable that the specific gravity of the molten metal 10 be high in order to obtain a sound cast product with no entrained gas or moat boundaries in the Rakuyo 10 filled into the cavity 3.

Therefore, when filling the cavity 3 with the hot water 10, the timing of pressurizing the pressurizing plunger 2 against the molten metal 10' in the sleeve 5 is delayed, and the molten metal 10 is poured into the cavity 3 only by lowering the counter plunger 7 from beginning to end. If it is allowed to flow in, there is a risk that it will cause a moat, etc., resulting in an unwholesome product. <Problems to be Solved by the Invention> Therefore, in order to deal with this, the gate 9 is closed by the counter plunger 7 in the initial state as described above, and only after the pressurizing plunger 12 starts pressurizing the port hot water 10. The counter plunger 7 is lowered, but in this case, the pressurizing plunger 12 is lowered relatively faster than the counter plunger 7 in consideration of the filling speed, and the set speed is set to be faster.

Therefore, before the descending counter plunger 7 passes through the gate 9, that is, before the gate is fully opened, pressure is applied to the molten metal 10 by the pressure plunger 12, and the molten metal 10 flows into the cavity 3 from the gate area. Since the molten metal is spouted as appropriate, the molten metal splatter adheres to the inside of the cavity 3 before filling is completely completed and solidifies early, resulting in the formation of a molten metal boundary without being fully fused with the subsequent filled molten metal.

Furthermore, since the filled molten metal is not filled in the same manner, the gas is disturbed in the cavity, and the gas is drawn in, which also leads to the formation of an unsound product.

The purpose of this invention is to solve the problems of the vertical die-casting equipment based on the prior art described above, and to eliminate the molten metal from flying in the cavity, and to create a sound die-casting machine without gas entrainment or moat boundaries. It is an object of the present invention to provide an excellent vertical die-casting apparatus which makes it possible to obtain a cavity product and which benefits the field of sun-filling application in the foundry industry.

<Means and operations for solving the problems> In order to solve the above-mentioned problems, the structure of the present invention, which is based on the above-mentioned claims, is to first attach a lower mold sleeve to an upper mold sleeve. After joining, the gate is closed, and in this state, the molten metal is supplied by V, and in the process of lowering the pressurizing plunger, the lower mold sleeve is lowered to open the gate, and the set amount of molten metal is applied to the cavity by its own weight. The molten metal is allowed to flow smoothly through the runner, which is formed in a downwardly tapered shape so that the molten metal can flow in. Only when the set amount of molten metal flows in and the flow is uninterrupted, the pressurizing plunger pressurizes the molten metal and works with the counter plunger to pump the molten metal. Technical measures have been taken to ensure filling until the end of casting.

Embodiments - Configuration> Next, embodiments of the present invention will be described below with reference to FIG. 2 and the subsequent drawings.

Note that the same parts as in FIG. 1 will be explained using the same reference numerals. A is a vertical die-casting apparatus according to an embodiment of the present invention, in which an upper mold 1 is clamped with a lower mold 2, a core 13 installed in advance is fixed in a cavity 3, and a die-cast product having an annular hollow part is produced. It is designed to be cast.

The cavity 3 is located below the gate 9 as shown in FIG. The two are connected by a moat 4' that slopes downward.

Further, the wound channel 4' is tapered from the gate 9 to the sprue 6 as shown in FIG.

Thus, the upper mold sleeve 5' is fixed to the upper mold 1, while
A lower die sleeve 5″ is provided to be movable up and down relative to the lower die 2.
is connected to a hydraulic cylinder 14 as a lifting device, and the lower mold sleeve 5'' is brought into close contact with the lower end of the upper mold sleeve 5' at a gate 9 to open and close the gate. A counter plunger 7 is inserted into the inside of ``in a relatively slidable manner, and a counter cylinder 8 is connected to the counter plunger 7.

Further, the pressurizing plunger 12 inserted into the upper die sleeve 5' is connected at its upper portion to the pressurizing cylinder 11.

A dog 16 provided on the shaft 15 is provided on a frame (not shown) or is allowed to come into contact with and pass through a mitt switch 17, and the yield mitt switch 17 is connected to a hydraulic pump actuating device via a relay control (not shown), and is connected to the hydraulic pump actuator 14 through a relay control (not shown). It is connected. For convenience, the cross-sectional area of the sprue is determined to be relatively large, such that the cross-sectional area of the sprue/product volume=0.01 to 0.08.

The pressurizing side hydraulic mechanism of the pressurizing cylinder 11 is configured to be able to determine the relative pressurization of the pressurizing plunger 12 with respect to the counter plunger 7 via a set pressure ratio device (not shown).

<Embodiment - Operation> In the above-described configuration, first, the lower mold sleeve 5'' is raised by the lifting diamond 14, and is brought into close contact with the upper mold sleeve 5'', and the gate 9 is closed.

In this state, a set amount of Rakuyo 10 is supplied into the upper die sleeve 5', and then the pressurizing cylinder 11 is operated to lower the pressurizing plunger 12.

Thus, the dog 16 of the rod 15 of the pressurizing plunger 12
When the pressure plunger 12 reaches the set position of the limit switch 17, the lifting device 14 is activated via the relay control, and the lower mold sleeve 5 is lowered by the set amount until the gate 9 is lowered. opens.

Therefore, since the pressurizing plunger 12 has not yet reached the stage of pressurizing the molten metal 10, the molten metal 1 is downwardly set from the gate 9 at an inclination Q=5o to 4? The molten metal 10 naturally flows smoothly into the cavity 3 through the tapered runner 4' due to its own weight.

In this case, the inflow of the molten metal 10 occurs naturally through the downwardly tapered scar, but in order to optimize the inflow speed and inflow capacity, the cross-sectional area of the sprue/product volume is designed to be 0.02 to 0.05. It is desirable to keep it.

In this way, when the molten metal 10 reaches 10% or more due to its own weight, the pressure plunger 12 comes into contact with one part of the molten metal according to the design in a process where the flow of the molten metal is not interrupted, and in cooperation with the counter plunger 7 The molten metal 10 is pressurized and the runner 4
′ starts filling the cavity 3 under pressure. At this time, if the molten metal is violently ejected, the above-mentioned conventional problem will occur. Therefore, in the present invention, the designed filling speed is set to four times or less than the gate speed during filling due to the dead weight, and at that speed, filling is performed at less than twice the gate speed.

By doing this, the filling molten metal 10 is filled in the cavity 3 at a low speed, so there is no formation of flaws or collapse of the gas in the cavity 3, and therefore, a sound die-cast product is obtained without gas entrainment. It will be done.

Further, by simply filling the molten metal 10 into the cavity 3 at a low speed by applying a potential energy difference to the molten metal 10, the runner 4' is formed in an inclined tapered shape, and the flaw 4' is formed in a tapered manner from the gate 9 to the sprue 6. This automatically increases the gravity filling rate at the initial stage of casting, improving casting accuracy.

Furthermore, since the filling is performed at low speed and under low pressure, breakage and galling of the core are less likely to occur, making it possible to use a sand core. Finally, the mold is removed, the product is reset, and the molten metal V supply is recycled. As a result of conducting tests according to the embodiments of the present invention in comparison with the secondary technology, it was found that the pressurizing pressure k applied to the molten metal by the pressurizing plunger on the machine shaft is as shown in Fig. 5.
9/ If p is the specific gravity P of the die-cast product on the vertical axis, it becomes clear that compared to the curve of conventional product C, the product 〇 curve according to this invention produces a much denser paid product. Ta. <Other Embodiments> It goes without saying that the embodiments of this invention are not limited to the above embodiments; for example, the core may be used for undercuts, and the runners may be curved. Various embodiments such as the above are possible.

It is also applicable to complex die casting that does not use a core.

Of course, it is also possible to design the molten metal's own weight filling speed, filling capacity, melt damage contact timing of the pressurizing plunger, pressurizing low pressure force, pressurizing filling speed, etc. as appropriate.
The gate opening/closing means is not limited to the method using the lower mold sleeve, but may also be performed using counter plunger control.

<Effects of the Invention> As described above, according to the present invention, the runner which allows the interior of the upper mold sleeve and the lower mold sleeve to pass through the cavity is formed in a downwardly inclined 7-par shape so that its own weight can flow into the cavity. Since it is tapered from the gate to the sprue, it not only allows the twill to flow smoothly through the runner, but also automatically increases the gravity filling rate at the initial stage of casting, making it possible to simply pressurize with a pressure plunger. Casting accuracy is higher compared to
The excellent effect is that a healthy product with improved layers and no hot water or gas entrainment can be obtained.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of vertical die casting based on the follow-up technology.
Figure 2 and the following are explanatory diagrams of embodiments of the invention of this application,
2 and 3 are vertical die-casting equipment, FIG. 4 is an enlarged explanatory view of the runner, and FIG. 5 is an explanatory view of experimental data. 5'... Upper die sleeve, 5'... Lower die sleeve, to 5... Lower die sleeve, 14...' Lifting device, 9... Gate, 12... ...Pressure plunger, 7
... Counter plunger, 10 ... Molten metal, 4' ... Runway, 6 ... Sprue, 3 ... Capity, A ...
...Vertical die casting equipment. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1 The lower die sleeve installed opposite to the fixed upper die sleeve is operated to open and close the gate via the lifting device, and the molten metal is pumped through the cooperative action of the pressurizing plunger and counter plunger installed in the upper die sleeve and the lower die sleeve. In a vertical die casting device in which the cavity is filled from a gate through a runner and a sprue, the runner that communicates the inside of the upper mold sleeve and the lower mold sleeve with the cavity is tilted downward so that its own weight can flow into the cavity. A vertical die casting device characterized by being formed into a tapered shape and tapering from the gate to the sprue.