JPS6023089Y2 - Vertical injection device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vertical injection device for injecting molten metal into a casting sleeve in a vertical die casting machine.

As a type of die-casting machine, a vertical die-casting machine with the injection and mold clamping directions perpendicular is disclosed in Japanese Patent Application Laid-Open No. 52-184, for example.
It is known from Publication No. 27.

This die-casting machine is equipped with a base platen fixed to the floor, etc., and a moving platen supported by tie bars installed upright on the base platen.The base platen has a fixed mold, and the moving platen has a movable mold. Installed individually.

Furthermore, an injection device for molten metal is installed in the pit below the pace platen, and during casting operations, after the mold is clamped, the ladle pours the molten metal into the casting sleeve of this injection device, and pours it into the fixed mold. Injection is performed by pressing.

However, since the casting sleeve in a conventional device of this type is integrally formed with a cylindrical body, there is a drawback that the injection speed slightly changes due to thermal expansion that varies depending on the position in the axial direction.

This will be explained using FIG. The figure shows a state in which the plunger tip P is in the lowered position, that is, in a state in which molten metal can be injected.

When molten metal is injected into this hole, as shown exaggerated in the same figure,
The casting sleeve S is located in the A part where the heat of the molten metal deforms in the radial direction, the B part where the influence of the molten metal heat is small and almost no deformation occurs, the upper part is located in the A part which is subject to deformation, and the lower part is located in the part A which is deformed. Because it is located in the B part, which is not affected by both parts, there is also the C part, which is affected by both.

Therefore, when the plunger tip P is raised in this state, molten metal remains between the inner wall surface of the A portion of the casting sleeve S and the circumferential surface of the plunger tip P, which makes the subsequent movement of the plunger tip P unsmooth. do.

In other words, not only does the injection speed vary due to galling between the plunger tip P and the solidified residual molten metal, but also
This causes a problem that the injected molten metal vibrates.

Such a phenomenon is particularly noticeable when the plunger tip P passes through a portion C that has been complicatedly deformed.

Furthermore, the casting sleeve is attached to the upper end of the docking frame that moves up and down below the fixed mold, and as extremely high temperature molten metal is repeatedly injected into this, this heat is transferred to the docking frame. On the other hand, the temperature of the molten metal often decreases as the heat is taken away by the docking frame, which often affects the quality of the product.

The present invention was developed in view of the above points, and includes dividing the cast sleeve into two sleeves, an upper and lower sleeve, at a position below the lower limit upper surface of the plunger tip, and interposing a heat insulating material in this divided portion. The present invention provides a vertical injection device that enables smooth injection by connecting the sleeves with a coupling, and prevents thermal deformation of the docking frame, etc. and deterioration of the quality of the cast product due to a drop in the temperature of the molten metal. be.

Hereinafter, its configuration and the like will be explained in detail with reference to embodiments shown in the drawings.

FIG. 1 is a sectional view of the injection device according to the present invention, and FIG. 2 is a sectional view of the upper end of the docking frame.

In these figures, a vertical die casting machine 1 includes a base platen 2 fixed to the floor, and a moving platen (not shown) that moves up and down along tie bars 3 erected on the base platen. A fixed mold 4 is mounted on the platen 2, and a movable mold 5 is mounted on the moving platen.

Further, in a pit provided below the base platen 2, an injection device, generally designated by the reference numeral 6, is provided.

The injection cylinder 7 of the injection device 6 has a lower end pivotally supported on the floor of the pit, and a piston 8 that is slidably moved up and down by a hydraulic device (not shown) is installed inside the cylinder 7. .

A docking frame 10 is provided above the injection cylinder 7 and is moved up and down by a dotting ram 9. At its upper end, a plunger tip 12 at the upper end of a plunger 11 is integrally attached to the piston 8.
is pivotally supported so that it can slide freely.

A casting sleeve 13 is attached to the upper end of the docking frame 10.

This cast sleeve 13 includes an upper sleeve 13a located above, a lower sleeve 13b located below and detachably fixed to the docking frame 10, and a heat insulating material interposed between these sleeves 13a and 13b. 14 and a coupling 16 that connects these three members 13a, 13b, and 14.

Then, the casting sleeve 13 is attached to both the upper and lower sleeves 13a, 1.
The position where the upper sleeve 13a is separated into the upper sleeve 13a is set so that the lower surface of the upper sleeve 13a is located below the upper surface of the plunger tip 12 at the lower limit.

Note that the position at which this cast sleeve is separated is preferably the middle position of portion C shown in FIG.

That is, the distance E from the lower limit upper surface position of the plunger tip P to the above-mentioned position varies depending on the diameter of the plunger tip P, but it is appropriate that the distance E is 1/3 to 1/20 of the diameter of the plunger tip.

However, 5TIr as much as possible! n or more, preferably 10y
It is desirable that it be about r+m or more.

On the other hand, the fixed mold 4 has a fixed sleeve 2 which fits into the casting sleeve 13 when the docking frame 10 is raised.
0 is inserted.

A tilting device 15 for tilting the injection cylinder 7 within the notch of the base platen 2 as shown by the chain line in FIG. 1 is provided on the side of the injection device 6 formed in this manner.

In the die casting machine 1 configured as above,
With the dotting frame 10 being lowered, the movable mold 5 is lowered together with the moving platen to close the mold, and then the injection cylinder 7 and the dotting frame 10 are
The molten metal is poured into the casting sleeve 13 by tilting them together.

Then, the injection cylinder 7 is vertically erected, the docking frame 10 is raised, and the upper end of the casting sleeve 13 is inserted into the fixed sleeve 20 of the fixed mold 4.

At the same time, when the piston 8 is raised, the plunger tip 12 at its tip pushes up the molten metal and forces it into the cavity formed by the fixed mold 4 and the movable mold 5.

After a predetermined period of time has elapsed, the mold is opened and the product is taken out, thereby completing the casting operation.

In such casting work, the casting sleeve 13
As extremely high-temperature molten metal is injected into the casting sleeve 13, the casting sleeve 13 is heated, but this consists of an upper sleeve 13a which thermally expands in the radial direction, and a lower sleeve 13a where the lower half of the plunger tip 12 is located and where no thermal expansion occurs. Since the upper sleeve 13a is divided into upper and lower parts in the axial direction, the upper sleeve 13a thermally expands uniformly at any position in the axial direction.

Therefore, if the diameters of both the upper and lower sleeves 13a and 13b are determined in consideration of this thermal expansion, unnecessary gaps between the plunger tip 12 and the inner wall of the sleeves and complicated deformation can be avoided. do not have.

This is because the inner diameter of the upper sleeve 13a can be set in advance to be slightly smaller than the inner diameter of the lower sleeve 13b so that it becomes the same as the inner diameter of the lower sleeve 13b during thermal expansion when the molten metal enters.

Further, since the heat insulating material 14 is interposed on the upper surface of the plunger chip 12, that is, below the lower surface of the molten metal, the heat of the molten metal is not directly conducted to the docking frame 10.

Further, since heat conduction is blocked by the heat insulating material 14, the heat of the molten metal is not removed by the docking frame 10.

Further, since the upper sleeve 13a in particular is worn out by high heat, it normally needs to be replaced about once a month, but since it is connected by the coupling 16, it can be easily replaced.

As is clear from the above description, according to the present invention, the casting sleeve is divided into upper and lower sleeves at a position below the upper surface of the plunger chip at the lower limit position, and the two sleeves are connected by a coupling. Since a heat insulating material is interposed between the upper and lower sleeves, the parts are divided into a part where thermal expansion occurs and a part where no thermal expansion occurs, so that the gap between the plunger tip and the cast sleeve can be maintained strictly.

Therefore, it is possible to prevent variations in the injection speed and vibrations of the molten metal caused by the molten metal remaining on the inner wall surface of the sleeve as in the prior art, and it is possible to obtain a homogeneous, high-quality finished product.

Further, since the heat of the molten metal poured into the casting sleeve is not conducted to the docking frame, thermal deformation of the docking frame can be prevented.

Furthermore, since the molten metal does not lose its heat to the dotting frame, the high temperature is maintained and the quality of the cast product is not degraded.

Another advantage is that only the upper sleeve, which is subject to severe wear and tear due to repeated heating, can be easily replaced.

[Brief explanation of drawings]

1 and 2 show an injection device for a vertical die-casting machine according to the present invention, FIG. 1 is a sectional view thereof, FIG. 2 is a sectional view of the upper end of the docking frame, and FIG. It is a sectional view for explaining a deformed state of a casting sleeve. 1... Vertical die casting machine, 4...
Fixed mold, 6...Injection device, 10...
Docking frame, 12...Plunger tip, 13...Cast sleeve, 13a...
...Upper sleeve, 13b...Lower sleeve,
11...Insulation material, 16...Coupling.

Claims (1)

[Scope of utility model registration request] The casting sleeve 13 installed at the upper end of the docking frame 10 that moves up and down below the fixed mold 4 is divided into an upper sleeve 13a and a lower sleeve 13b at a position slightly below the upper surface of the plunger tip 12 at its lower limit position.
These upper and lower sleeves 13a, 13 are formed by
A vertical injection device characterized in that a heat insulating material 14 is interposed between the upper and lower sleeves 13a and 13b, and a coupling 16 connects the upper and lower sleeves 13a and 13b.