JP3036673B2 - Injection sleeve for die casting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold chamber type injection sleeve for die casting or squeeze casting of non-ferrous metals such as aluminum alloys and zinc alloys.

[0002]

2. Description of the Related Art Conventionally, in a horizontal clamping and horizontal casting type die casting machine, a plunger tip 9 is slidably housed in an injection sleeve 7 having a pouring port 10 at one end, and the other end of the injection sleeve 7 is provided. Is communicated to the product cavity 6 formed between the molds through a gate, and the molten metal 11 in the injection sleeve 7 is filled into the cavity 6 and solidified by the entry of the plunger tip 9. I have.

[0003]

However, such a conventional injection sleeve 7 has the following problems. That is, the air 1 existing above the injection sleeve 7
2 is the air 1 in the injection sleeve 7 when the molten metal 11 is injected.
2 and press-fit into the cavity 6 as it is, resulting in a large number of cavities, deteriorating the strength, pressure resistance, skin and the like of the casting.

The air 12 above the injection sleeve 7 is
As shown in FIG. 7, an air vent hole 13 is provided in the upper part of the injection sleeve 7 to smoothly discharge the air. In particular, if the air vent hole 13 is provided at a position where the plunger tip 9 switches from the low speed to the high speed, there is an advantage that the air 12 in the injection sleeve 7 can be more smoothly discharged. The switching position to the high speed is performed, for example, at a position relatively close to the gate 14 portion, such as gate driving, when a small hot spot is desired inside the molded product even if some hot lines occur outside the molded product. I have.

On the other hand, if it is desired that the molded product has a large number of voids inside the molded product and a glossy one with no hot water on the exterior of the molded product, the position is switched from low speed to high speed as soon as the injection is started, and the position is moved each time. The position of the air vent hole 13 must be changed at the same time with this movement.

When die casting is performed using the molten metal 11 which is relatively easy to solidify, it is necessary to switch from low speed to high speed in a short time from the start of injection (a position away from the gate 14). On the contrary, when the die casting is performed using the molten metal 11 having a slow solidification, it is necessary to switch the position from the low speed to the high speed at a position close to the gate 14, and to move the position of the air vent hole 13. There is a problem that it is practically impossible to replace the injection sleeve 7 each time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and provides an injection sleeve for die casting in which air in the injection sleeve can be freely removed in accordance with a switching position from a low speed to a high speed. The purpose is to do so.

[0008]

In order to achieve the above-mentioned object, the present invention has a pouring port at an upper portion in which a molten metal is cast into a cavity of a clamped mold from a horizontal direction.
An inverted trapezoidal cross section is formed on the upper surface of the inner circumference of the horizontal injection sleeve, which is located at the speed switching position from low to high.
Correspondingly, fitting members having different lengths can be attached to the concave notches , and the fitting members are not mounted through the concave notches.
The air in the injection sleeve was allowed to escape from the pouring port .

[0009]

According to the present invention, a concave notch is provided on the upper surface of the inner circumference of the injection sleeve in accordance with the switching position from the low speed to the high speed at the time of injection, and the fitting members having different lengths are exchanged therein. The remaining recessed part that is not installed becomes an air bleed path, and the upper air of the molten metal in the injection sleeve can be discharged smoothly, so that molded parts with no hot lines or cavities inside and outside of the molded part it can.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an injection sleeve for die casting according to the present invention.

FIG. 1 is a sectional view showing an embodiment of a die casting apparatus having an injection sleeve according to the present invention, FIG. 2 is a sectional view of the injection sleeve when pouring of molten metal is completed, and FIG. 3 is injection at a low speed. FIG. 4 is an explanatory diagram showing the air flow in the sleeve, FIG. 4 is an explanatory diagram showing the air flow in the injection sleeve immediately before switching from low speed to high speed, and FIG. 5 is an explanatory diagram showing the air flow in the injection sleeve at high speed. FIG. 6 and FIG. 6 are cross-sectional views as viewed from A to A in FIG.

In FIG. 1, reference numeral 22 denotes a fixed base 20.
The movable platen 22 is slidably provided in the left-right direction by a hydraulic piston (not shown).

A die base 24 is fixed to one side surface of the movable platen 22, and a movable mold 26 is fixed to the die base 24.

Reference numeral 28 denotes a fixed platen fixed on the fixed base 20, and a fixed mold 30 is fixed to the fixed platen 28.

When the movable mold 26 slides rightward in the drawing and comes into contact with the fixed mold 30, the movable mold 26 and the fixed mold 3
0 and the product cavity 6
And a gate 14 connecting the runner part 32 to the gate.

One end of the injection sleeve 7 is opened in the runner portion 32, and the plunger tip 9 is inserted from the other end of the injection sleeve 7.

Then, the molten metal 11 is injected from a pouring port 10 provided in the injection sleeve 7, and the plunger tip 9 advances to the left in the drawing, so that the molten metal 11 is formed in the runner portion 32, the gate 14, and the product cavity 6. Leads to.

The product cavity 6 and the runner section 32
The push pin 3 fixed to the push plate 36 is located at a position facing
8 and serves to push the product when the movable mold 26 and the fixed mold 30 are opened.

Reference numeral 40 denotes an exhaust valve, and reference numeral 42 denotes a limit switch for detecting a speed switching position of the plunger tip 9 from a low speed to a high speed.

In this embodiment, in particular, as shown in FIG. 6, a recess 7b having a predetermined length and a cross section having a reverse trapezoidal shape is formed on the upper surface 7a in the axial direction of the inner circumference of the injection sleeve 7.

The concave notch 7b is formed from the vicinity of the fixed platen 28 of the injection sleeve 7 to the rear end side of the injection sleeve 7, and a fitting member 7c having a trapezoidal cross section can be attached to the concave notch 7b. ing.

The fitting member 7c can be replaced with one having various lengths L in accordance with the type of the molten metal 11 and the desired internal and external initial specifications of the molded product. Reference numeral 44 denotes a holding bolt for fixing the position of the fitting member 7c, and reference numeral 40 denotes an exhaust valve.

Next, the operation of this embodiment will be described.

First, the movable mold 26 is advanced to move the fixed mold 3
0, and mold clamping is performed. Then, the exhaust valve 40 is opened.

Next, a predetermined amount of molten metal is injected from the pouring port 10 of the injection sleeve 7 (FIG. 2).
At low speed (FIGS. 3 and 4), and the limit switch 42
At that point, you move forward at high speed.

By the way, the air 12 in the injection sleeve 7 in correspondence to the speed switching position is long species people that can escape sufficiently from concave portion 7b of the unattached portion of the fitting member 7c to high speed low speed Although the fitting member 7c having the length L can be mounted, the fitting member 7c is generally based on the following concept.
It changes the length of c.

First, generally used Al-Si-C
For relatively slow solidification of the molten metal 11 in the case of using the aluminum alloy of u based ADC 12 (including copper SILUMIN), the limit switch 42 the speed switching position to a high speed from the low speed position approaching the gate 14 Will be detected. For this reason, the fitting member 7c is relatively short.

Next, Al—
In the case where an Mg-based ADC5 or ADC6 (hydronalium) aluminum alloy is used, or in the case of rotor casting using pure Al, the solidification of the molten metal 11 is rapid, so that it takes a relatively short time from the start of injection (a position away from the gate 14). The switching from the low speed to the high speed is performed, so that the fitting member 7c is relatively long.

Molten metal 1 poured into injection sleeve 7
When the plunger tip 9 is filled into the product cavity 6 by the high-speed advance of the plunger tip 9, it is difficult to release the air 12 from the recessed portion 7b of the portion where the fitting member 7c has not been mounted. Since it is open, the air 12 of the remaining injection sleeve 7 is discharged to the atmosphere through the runner part 32, the gate 14, the product cavity 6, and the exhaust passage 46.

After a lapse of a predetermined time (set by the timer), the exhaust valve 40 is closed by moving the rod 9a to the left in FIG. All the molten metal 11 is injected into the product cavity 6.

Thereafter, when the molten metal 11 filled in the product cavity 6 has been solidified, the movable mold 26 is moved leftward in FIG. 1 to open the mold, and the extrusion pin 38 is extruded to form a molded product ( Product). The operations described above are repeated to perform die casting.

[0032]

As is apparent from the above description, the present invention has a pouring port at the upper portion where the molten metal is cast into the cavity of the clamped mold from the horizontal direction.
An inverted trapezoidal cross section is formed on the upper surface of the inner circumference of the horizontal injection sleeve, which is located at the speed switching position from low to high.
Correspondingly, fitting members having different lengths can be attached to the concave notches , and the fitting members are not mounted through the concave notches.
By releasing the air in the injection sleeve from the pouring port, it is possible to freely select the speed switching position from low speed to high speed according to the type of molten metal and the specifications of the inside and outside of the molded product. Since the air can be sufficiently vented, a molded article excellent in strength, pressure resistance, skin and the like can be easily molded.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a die casting apparatus having an injection sleeve according to the present invention.

FIG. 2 is a sectional view of the injection sleeve when pouring of molten metal is completed.

FIG. 3 is an explanatory diagram showing a flow of air in an injection sleeve at a low speed.

FIG. 4 is an explanatory diagram showing a flow of air in an injection sleeve immediately before switching from a low speed to a high speed.

FIG. 5 is an explanatory diagram showing an air flow in the injection sleeve at a high speed.

FIG. 6 is a cross-sectional view as viewed from AA of FIG. 2;

FIG. 7 is a sectional view of a conventional die casting apparatus having an injection sleeve.

[Explanation of symbols]

 Reference Signs List 6 Product cavity 7 Injection sleeve 7a Inner peripheral upper surface 7b Depressed notch 7c Fitting member 9 Plunger tip 10 Pouring port 11 Molten metal 12 Air 13 Air release section 14 Gate 22 Movable platen 26 Movable mold 28 Fixed platen 30 Fixed mold 32 Runner Part 36 Extrusion plate 42 Limit switch

Claims (1)

(57) [Claims] 1. A pouring hole is provided at an upper portion of a mold to which a molten metal is cast into a cavity of a clamped mold from a horizontal direction.
An inverted trapezoidal cross section is formed on the upper surface of the inner circumference of the horizontal injection sleeve, which is located at the speed switching position from low to high.
Correspondingly, fitting members having different lengths can be attached to the concave notches , and the fitting members are not mounted through the concave notches.
An injection sleeve for die casting, wherein air in the injection sleeve is released from a pouring port .