JPH07214274A - Vertical die casting method and device - Google Patents

Abstract

PURPOSE:To obtain an highly strong die cast product that is dense and without blow holes by arranging between a lower die and an upper die a slide core capable of opening and closing horizontally and thereby casting molten metal into a shaped cavity from a vertical lower part. CONSTITUTION:A slide core 23 in a closed state is arranged between a lower die 11 and the upper die 12 capable of opening and closing vertically, which can be opened and closed horizontally by cylinder 24 and is constituted of a cavity 21 and a gate 22 for casting molten gate at a vertical split face part 20 from the top side. Then, the die is clamped; the molten metal is flowed into a casting sleeve 17, which is provided in the through hole 15 fixed in the lower die 11, by a plunger 16 for pressurizing, and flowed inside the entire cavity 21 through a molten metal passage 18, gate hole part 22a, gate branch part 22b and groove part 22c. At this time, the casting sleeve 17, molten metal passage 18 and the gate 22 are in the vertically lower part of the cavity 12; therefore, the casting is performed in the state where the flow of the molten metal as well as the discharge of gas is satisfactory, and the transmission of pressure is also sufficient.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die casting method and apparatus, for example, an I-shaped or H-shaped cross section.
It is also suitable for obtaining cast products such as shapes.

[0002]

2. Description of the Related Art Conventionally, it has been known that in casting by a vertical die casting machine, a gas discharged from a die cavity can be discharged well at the time of casting, so that a cast product having properties relatively close to forging can be obtained. However, if you want to obtain die-cast products with I-shaped or H-shaped cross-sections or similar cross-sectional shapes,
Conventionally, for example, as shown in FIG. 5, a lower die 1 and an upper die 2 which can be opened and closed in the vertical direction are used, and a casting sleeve 4 is placed on the lower die 1 at a position laterally displaced from below the cavity 3. Die casting was performed using a device that was fixedly provided. Further, the gate 6 that connects the molten metal passage 5 that also functions as a feeder port above the casting sleeve 4 and the cavity 3 is arranged in the lateral direction.

[0003]

In the above-mentioned conventional apparatus, the gate 6 is arranged laterally, and the molten metal passage 5 and the gate 6 which are also feeders intersect at a right angle. Since the molten metal inlet 3a also intersects at a right angle and is designed to be cast from one lateral direction, the casting pressure by the pressing action of the plunger tip 7 in the casting sleeve 4 is sufficient for the molten metal in the cavity 3. I could not communicate. In addition, gas escape was poor, and the flow of molten metal was not good. As a result, it was not possible to obtain a die-cast product having desired compactness and strength.

[0004]

The present invention is intended to eliminate such drawbacks. As a mold structure, a slide core for splitting left and right is provided in addition to an upper die and a lower die, and a split surface is provided on the split surface. By installing the runner, the flow of the hot water is improved, the gas is eliminated, and the pressure can be transmitted sufficiently. That is, in the present invention, a slide core having a cavity and a gate portion for molten metal casting provided on a vertical dividing surface portion from the upper side is provided between a lower mold and an upper mold so as to be horizontally openable and closable. A vertical die-casting device was used, in which a passage for molten metal casting was provided in the vertical direction in the lower die located below the gate of the closed slide core, so that die casting was performed.

[0005]

[Function] Between the lower mold and the upper mold that can be opened and closed in the vertical direction, a slide core having a cavity and a gate for pouring molten metal is closed from the upper side on a vertical dividing surface part that can be opened and closed horizontally. After arranging in a state and clamping, the molten metal is cast vertically downward from above into the cavity through the molten metal casting passage and the gate directly below the gate in the lower die. In this case, since the molten metal pouring passage, which also serves as a feeder port, and the gate and the center of the cavity are aligned vertically, the flow of molten metal is good, the gas is discharged well, and pressure transmission is sufficient. In this way, a dense, nest-free, high-strength die-cast product is obtained.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In one embodiment of the present invention shown in FIGS. 1 to 4, 11 is a horizontal lower mold, 12 is a horizontal upper mold which can be opened and closed in the vertical direction, and the lower mold 11 is a horizontal mold. It is fixed to a fixed platen 13, and the upper die 12 is fixed to a horizontal movable platen 14 which can be opened and closed vertically.

A through hole 15 is provided in the center of the stationary platen 13, and a casting sleeve 17 having a plunger tip 16 slidably provided therein is provided in the through hole 15 from below so as to be freely inserted and removed. The upper end portion of the casting sleeve 17 can be docked from below to the lower end portion of the vertical molten metal passage 18 in the central portion of the lower mold 11. 1
Reference numeral 9 denotes a plunger which is integrated with the plunger tip 16 and is vertically moved by an injection cylinder (not shown).

On the lower side of the horizontal lower surface of the upper mold 12, a pair of two cavities 21 having an I-shaped cross section and a gate 22 for molten metal casting are provided on the vertical dividing surface 20 from above. The slide core 23 is provided so as to be slidable in the horizontal direction and openable and closable. Reference numeral 24 is a cylinder for opening and closing the slide core 23, and 25 is a piston rod.
4 is attached to the flange portion 12a at the end of the upper die 12. The lower portions of both side surfaces of the slide core 23 are tapered so that they are engaged with the taper portion of the inner surface of the upper portion of the lower mold 11, and the horizontal portion of the lower surface of the slide core 23 is also horizontal to the inner surface of the lower die 11. It is designed to be pressed against the section. Reference numeral 26 designates a pin which serves as a key for preventing the closed slide core 23 from opening. The cylinder 26, which is not shown in the figure, inserts / removes the slide core 23 into / from the hole 23a in the upper part of the slide core 23 from the upper mold 12 side. It is supposed to be done.

The upper horizontal portion 21a of the horizontally long cavity 21 having an I-shaped cross section is formed between the lower surface of the upper mold 12 and the upper surface of the slide core 23. Slide core 23
The gate 22 formed on the divided surface 20 of the slide core 23 is provided at the center of the divided surface 20 of the slide core 23 from below, and can be halved. When the slide core 23 is closed, a truncated cone is formed. -Shaped gate hole portion 22a, a gate branch portion 22b extending from the upper part of the gate hole portion 22a toward both sides in the longitudinal direction of the cavity 21 along the dividing surface 20, and from above the gate branch portion 22b. A plurality of grooves 2 extending vertically toward the bottom of the cavity 21.
And 2c. The gate hole 22a is
The diameter is about half the inner diameter of the casting sleeve 17 and the outer diameter of the plunger tip 16.

Below the gate hole 22a formed in the center of the lower part of the split surface 20 of the slide core 23, a melt passage 18 formed in the shape of a vertical through hole in the center of the lower mold 11 is located. ing. As shown in FIG. 3, the lower portion of the molten metal passage 18 has the same inner diameter as the inner diameter of the casting sleeve 17, but the upper portion of the molten metal passage 18 has an inner diameter portion 18a slightly larger than the inner diameter of the casting sleeve 17. Further, a shallow large-diameter portion 18b is formed on the upper surface of the lower mold 11 above the inner diameter portion 18a. Reference numeral 27 is a wire mesh which is arranged in the large diameter portion 18b for each casting.

The operation of this embodiment will be described below. First, in the mold open state, both slide cores 23 are closed by the action of the cylinder 24 from the state shown in FIG. At this time, the split surfaces 20 of both slide cores 23 are pressed against each other to form a desired cavity 21. When the slide core 23 is closed, the slide core 2
The pin 26 is lowered and the tip end is inserted into the hole 23a of the slide core 23 so that 3 does not open accidentally. In this state, the metal net 27 is placed in the upper large diameter portion 18b of the molten metal passage 18.

Next, the movable platen 14, the upper mold 12 and the closed slide core 23 are lowered by the action of a cylinder (not shown) to perform mold clamping. On the other hand, on the outside of the fixed platen 13, the molten metal is poured into the casting sleeve 17 in which the plunger tip 16 is retracted, the state is maintained, and the casting sleeve 17 is inserted from the lower side of the through hole 15. , Casting sleeve 1
The upper end of 7 is pressed against the lower portion of the molten metal passage 18 of the lower mold 11 to be docked. Plunger tip 16 in this state
And the molten metal is cast into the cavity 21. The state at this time is as shown in FIG.

When pouring, the molten metal in the pouring sleeve 17 in the vertical state passes through the molten metal passage 18 directly above and enters the gate hole 22a in the vertical state immediately above, and from there, the gate branch 22b. And spreads in the lateral direction, and flows into the entire cavity 21 through a large number of vertical grooves 22c. In this case, since the molten metal flows relatively downward from the bottom to the top, the flow of the molten metal is good and the cavity 2
The gas in 1 is cast in a good state. Further, in this case, in the molten metal passage 18, since the inner diameter of the inner diameter portion 18a is slightly larger than the inner diameter of the casting sleeve 17 or the outer diameter of the plunger tip 16, oxides generated along the inner wall surface of the casting sleeve 17 are generated. A large amount of the cylindrical chill layer is destroyed at the inner diameter portion 18a or by hitting the lower surface of the slide core 23 around the gate hole portion 22a and stored in the inner diameter portion 18a. Of course, the gate hole 22a has a smaller diameter than the outer diameter of the plunger tip 16, and, for example, as shown by the alternate long and short dash line in FIG.
Since it is located at an inner position of about 45 degrees from the outer peripheral surface of the upper end of the plunger tip 16 which is in the ascending limit position during casting, the range where the chill layer accumulates is wide, and the chill layer is inside the gate hole 22a. The chill layer and the oxide film are prevented from entering the cavity 21 and the casting product.

In addition to this, since the wire net 27 is placed in the large diameter portion 18b of the molten metal passage 18 in front of the gate hole 22a, the chill layer which still tries to enter the gate hole 22a is prevented, or Even if it cannot be completely prevented, by reducing the chill layer and oxide layer, the flow of molten metal during casting will not be obstructed, and a good quality cast product can be obtained. At this time, the wire net 27 is pushed up by the molten metal and hits the lower end surface of the gate hole 22a, and becomes somewhat uneven. However, due to the unevenness of the wire net surface, the chill layer or the oxide film is applied from the outer periphery to the gate 22. It is prevented from slipping in.

When the molten metal is filled in the cavity 21,
Although the pressing force due to the action of the plunger tip 16 is partly in the lateral direction at the gate branch portion 22b, but is almost in the vertical direction, it acts on the molten metal in the cavity 21 as a relatively large pushing force, and the cast product. To be precise.

When the casting operation is completed and the casting product 28 is cooled to some extent, the pin 26 is opened after the mold is opened as shown in FIG.
Back to open the slide cores 23 on both sides. At this time, the biscuit part 29 at the lower part of the cast product 28 is grasped or received by a product take-out device (not shown), and the cast product 28 and the biscuit part 29 are taken out of the machine to obtain the cast product 28. And the biscuit portion 29 is cut off. During this time, the plunger tip 19 is retracted, the casting sleeve 17 is lowered, the upper portion of the casting sleeve 17 is moved to the outside of the machine, and pouring is waited for the next cycle.

Although the slide core 23 is slidably provided on the lower surface of the upper mold 12 in the first embodiment, it may be slidably mounted on the upper surface of the lower mold 11 in some cases. You can also

[0018]

As described above, according to the present invention, the vertical die-casting method is used to vertically open and close horizontally between the lower mold and the upper mold which can be opened and closed in the vertical direction. The slide core, which has a cavity and a gate for molten metal pouring from the upper side on the surface, is placed in a closed state, and after mold clamping, the molten metal is cast into the cavity from below through the molten metal pouring passage and gate in the lower mold. In addition, since a device for that purpose is provided, even if a cast product having a cross-sectional shape such as an I-shape or an H-shape is obtained, the resistance in the cavity is relatively lower than below. The molten metal can be cast in this state. As a result, the pushing force can be well transmitted to the molten metal in the cavity, the flow of the molten metal is good, the gas in the cavity is discharged well, and the chill layer and oxide film generated in the molten metal in the casting sleeve are also cavities. It's easy to keep it out,
It is possible to easily and surely obtain a cast product which is dense and has excellent mechanical properties.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing one embodiment of an apparatus for carrying out the method of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is an enlarged view of a part of FIG.

FIG. 4 is a vertical cross-sectional view showing a state when a cast product is taken out in one embodiment of the present invention.

FIG. 5 is a vertical sectional view showing an example of a conventional device similar to the present invention.

[Explanation of symbols]

 1,11 Lower mold 2,12 Upper mold 3,21 Cavity 4,17 Casting sleeve 5,18 Molten metal passage 6,22 Gate 7,16 Plunger tip 20 Dividing surface 23 Slide core 24 Cylinder 27 Wire net 28 Casting product

Claims (2)

[Claims] 1. A slide core, which is horizontally openable and closable, has a cavity and a gate for molten metal casting from the upper side between the lower mold and the upper mold which can be opened and closed in the vertical direction. A vertical die casting method in which the molten metal is placed in a closed state and clamped, and then the molten metal is cast into the cavity from below through the molten metal casting passage and gate in the lower die. 2. A slide core in which a cavity and a gate portion for casting molten metal are provided from above on a vertical dividing surface portion is provided between a lower die and an upper die so as to be openable and closable in a horizontal direction, and is closed. A vertical die casting device in which a passage for molten metal casting is vertically provided in a lower die portion located below a gate portion of a slide core.