JPS5925584Y2 - Mold equipment for molten metal forging - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a mold device for molten metal forging that solidifies molten metal under pressure within a product cavity.

The applicant of the present invention has previously developed a device of this type that includes at least one pair of split molds that divide the mold body in vertical cross section, and a product cavity located horizontally or at the joint surface of the split molds, and a product cavity located at the center of the split molds. A runner is formed on the outside of the product cavity and extends from the bottom of the product cavity to the spout above, and the runner is formed in the product cavity with the air in the product cavity replaced with an inert gas in advance. We proposed a system in which the molten metal could be poured from the bottom side of the runner without exposing it to air, but in this method, the joint surface where the runner was formed was distorted by the heat of the molten metal flowing inside the runner. occur unevenly,
This is accompanied by the inconvenience of warping of the split mold and poor mold clamping.

The purpose of the present invention is to provide an apparatus that eliminates such inconveniences, and is composed of at least one pair of split molds 2, 2 that divide a mold body 1 in vertical cross section, and the joint surface 2 , which is located in the center and forms a product cavity 3 and a runner 5 which is located on the outside of the product cavity 3 and extends from the bottom of the product cavity 3 to the pouring spout 4 above. A trough 6 is formed on the joint surface, located on the outer side opposite to the part where the runner 5 is formed, extends upward from the bottom of the product cavity 3, and has an internal volume approximately equal to that of the runner 5. It consists of

The illustrated mold device is for obtaining an engine piston, and includes an upper core mold 7 inserted into a product cavity 3 and a lower pressure pan 19 inserted into a through hole 8 in the bottom of the mold body 1. Equipped with

The runner 5 is formed in the form of a slit in order from the pouring spout 4 toward the communication part with the product cavity 3, as shown in FIGS. 3 to 5. The flow rate is gradually reduced so that the molten metal flows quietly into the product cavity 3, and at the same time, as the width of the runner 5 becomes narrower, the oxides mixed into the molten metal are absorbed into the inner wall of the runner 5. It is now possible to attach and remove.

The hot water reservoir 6 is formed in the shape of a slit with an intermediate part over its entire length so that its internal volume is approximately equal to that of the runner 5.

In the drawings, reference numeral 10 indicates a lid provided on the upper surface of the mold body 1, and the lid 10 is in an open position where a through hole 11 bored therein communicates with the pouring spout 4, and in an open position where the through hole 11 and the pouring spout 4 are connected to each other. When the core mold 7 moves downward, it is pressed against the upper surface of the mold body 1.

Next, to explain its operation, first, with the split molds 2 and 2 butted against each other, the core mold 7 is loosely inserted into the product cavity 3 from above, and the lid body 10 is rotated to the open position and poured from the pouring port 4. Inject inert gas.

As the inert gas, gases such as nitrogen, carbon dioxide, argon, and sulfur hexafluoride, which have a higher specific gravity than air, are used.
The air inside the product cavity 3 is replaced by the inert gas flowing into the product cavity, and then molten metal is poured from the pouring port 4.
The molten metal flows into the bottom of the product cavity 3 through the runner 5, and the product cavity 3 is filled with the molten metal while being cut off from contact with air.

At this time, distortion occurs due to the heat of the molten metal on the joint surface on one side of the split molds 2 and 2 that formed the runner 5, but according to the present invention, distortion is caused in the pool 6 formed on the joint surface on the other side. Since the inflow of molten metal causes distortion evenly on the joint surface on the other side, warping of the split molds 2, 2 is prevented as much as possible, and no mold clamping failure occurs.

Thereafter, the lid body 10 is rotated to the closed position, the core mold 7 is completely inserted into the product cavity 3, and the pressure punch 9 is moved upward to solidify the molten metal in the product cavity 3 under pressure.

In this way, according to the present invention, on the joint surface of the split molds 2, 2,
A runner 5 is located on the outside of one side of the product cavity 3, and a runner 5 is located on the outside of the other side and extends upward from the bottom of the product cavity 3, similar to the runner 5, and is generally referred to as runner 5. A pool 6 with the same internal volume is formed, and the molten metal flowing into the pool 6 creates a strain on the joint surface on the other side that is equal to the strain generated on the joint surface on the - side, causing cracking. Type 2
This has the effect of preventing warpage of .degree.2, ensuring good mold clamping, and reliably solidifying the molten metal in the product cavity 3 under pressure.

[Brief explanation of drawings]

Figure 1 is a cutaway side view of an example of the device of the present invention, and Figure 2 is a side view of one example of the device of the present invention.
The plan view taken along the line ■I-■■ in the figure, Figures 3 to 5 are
It is an enlarged sectional view taken along line III-III to line ■-■ in the figure. 1...Mold body, 2...Split mold, 3...
...Product cavity, 4...Pouring spout, 5.
...Hot water path, 6...Hot water pool.

Claims (1)

[Scope of utility model registration request] It consists of at least one pair of split molds 2, 2 that divide a mold body 1 in a vertical cross section, and a product cavity 3 located at the center of the joint surface 2 and a product cavity 3 located at the center of the joint surface 2, and a product cavity 3 located at the outside of the product cavity 3. The pouring spout 4 is located above the bottom of the product cavity 3.
In the type for fertilizing a runner 5 that extends from the bottom of the product cavity 3, the joint surface 1 is located on the outer side opposite to the part forming the runner 5 and extends upward from the bottom of the product cavity 3. A molten metal forging mold device comprising a molten metal pool 6 whose internal volume is approximately equal to that of the runner 5.