CN201217019Y - Die for Semi-solid Squeeze Casting Aluminum Alloy Piston - Google Patents

Abstract

The utility model provides a die for casting an aluminum alloy piston by semi-solid extrusion. The die comprises an upper die which is provided with a male die, a lower die which is provided with a female die, and a material discharging subassembly which is provided with an ejector rod and a release link. The die is characterized in that heating elements are respectively arranged in the male die of the upper die and the female die of the lower die. The male die and the female die can be respectively preheated, thus solving the problem that due to low temperature, semi-solid slurry solidifies quickly before the male die exerts pressure, which influences the subsequent molding process and leads to poor pressing effect. In the following continuous production, whether to continue to heat can be decided according to the temperature of the die so as to save energy. A high-quality piston casting with stable size without shrinkage porosity and pores can be obtained, and the casting can be processed into a piston product only through a small amount of mechanical machining. The die is high in precision and successfully realizes continuous extrusion casting of semi-solid aluminum alloy pistons.

Description

Die for Semi-solid Squeeze Casting Aluminum Alloy Piston

technical field

The utility model relates to a mold of an aluminum alloy piston for semi-solid extrusion casting.

Background technique

Semi-solid combined high-pressure casting or squeeze casting technology is a new type of part forming technology. Compared with traditional full liquid casting, it has low working temperature, small heat load of mold, finer and more uniform microstructure of products, and fewer defects and segregation. , so the performance is higher, close to all solid state forging. But there is no report on the practical application of semi-solid forming technology on pistons. Among them, the mold is a key technical issue. In ordinary squeeze casting, due to the large difference in the thickness of each longitudinal section of the piston, the shrinkage rate of the liquid aluminum metal from high temperature to the demoulding temperature is very large, which makes the piston casting prone to defects such as shrinkage porosity and pores, and the mold is exposed to heat. The impact is large, which is not good for the service life. The use of semi-solid slurry for squeeze casting can alleviate many of the above difficulties and is conducive to improving the quality and performance of piston castings. But at the same time, due to the lower pouring temperature and fast solidification of the semi-solid slurry, the temperature requirements for the mold are stricter than ordinary casting, and the forming pressure is higher. At the same time, direct squeeze casting has the problem of poor dimensional stability of castings. Therefore, it is absolutely necessary to improve the existing mould.

Contents of the invention

In order to overcome the deficiency that the existing piston mold is difficult to complete semi-solid slurry casting due to low temperature, the utility model provides a semi-solid extrusion casting aluminum alloy piston mold.

The utility model is realized through the following technical proposals: a semi-solid extrusion casting aluminum alloy piston mold, including an upper mold with a convex mold, a lower mold with a concave mold, and an unloading assembly with an ejector rod and a reset rod , which is characterized in that heating elements are respectively provided in the convex mold of the upper mold and the concave mold of the lower mold, so that the semi-solid aluminum alloy is hot-press-cast into a piston with the convex and concave molds with temperature.

The heating element in the punch of the upper die is an electric heating rod, which is longitudinally arranged in the middle of the punch so as to heat the punch.

The heating element on the concave mold of the lower mold is an electric heating wire wound around the outer wall of the concave mold so as to heat the concave mold.

The convex die of the upper die is provided with an upper pressing block, an upper die frame and a guide sleeve in turn, and an upper cover plate is arranged above them, so as to improve the matching accuracy of the upper die and the lower die and ensure the quality of the casting.

A lower mold frame and guide pillars are arranged outside the concave mold of the lower mold, and a lower support plate, a hollow cushion cover and a lower bottom plate are arranged below them in order to improve the matching accuracy of the upper and lower molds and ensure the quality of the casting.

The lower ends of the ejector rod and the reset rod of the unloading assembly are fixed on the fixed plate located in the hollow of the lower mold cushion cover, and the upper ends are respectively placed in the through holes corresponding to the die and the lower mold frame. The lower top plate in the hollow part of the mold cushion cover is connected, and the lower top plate is connected with the ejection cylinder of the extruder, so that under the action of the extruder, the lower top plate and the fixed plate can be pushed up and down in the hollow part of the cushion cover, so that after the casting is ejected Return to the position again, in order to squeeze again usefulness.

Compared with the prior art, the utility model has the following advantages and effects: adopting the above-mentioned scheme, the punch and the die can be preheated separately in advance, which solves the problem that the temperature of the semi-solid slurry is low and solidifies quickly before the punch is pressed. However, problems such as affecting subsequent molding and poor pressure application, and in subsequent continuous production, the temperature of the mold can be used to determine whether to continue heating to save energy. At the same time, high quality with no shrinkage, no porosity, and stable dimensions can be obtained. Piston castings, the obtained castings only need a small amount of machining to form piston products, with high precision, and successfully realized the continuous extrusion casting of semi-solid aluminum alloy pistons.

Description of drawings

Fig. 1 is the structural representation of the utility model.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described.

As shown in Fig. 1, the mold of the semi-solid extrusion casting aluminum alloy piston provided by the utility model is composed of an upper mold, a lower mold and a discharge assembly, wherein the upper mold includes an upper cover plate 1 and a parallel one located below the upper cover plate 1 The punch 2, the upper mold frame 4, the upper pressure block 7 and the guide sleeve 9 are arranged sequentially from the inside to the outside. The center of the punch 2 is provided with a longitudinal electric heating rod 3; the lower mold includes a lower bottom plate 19 and bottom-up Cushion 15, support plate 14, lower mold frame 13, guide post 8 and middle die 10 placed on lower base plate 19, electric heating wire 11 is wound around the outer wall of die 10; 15 The lower top plate 18 and the fixed plate 17 in the hollow 16, the reset rod 12 and the lower end of the ejector rod 20 are fixed on the fixed plate 17, the upper end of the reset rod 12 is placed in the corresponding through hole of the lower mold frame 13, and the ejector rod 20 The upper end of the upper end of the die is placed in the corresponding through hole of the die, and the lower top plate 18 is connected with the ejection cylinder 21 of the extruder, so that the lower top plate 18, the fixed plate 17 and its reset rod 12, and the ejector can be pushed out under the action of the ejection cylinder 21. The rod 20 moves up and down in the hollow 16 of the cushion cover. Its working process is: first heat the male mold 2 and the concave mold 10 to the required temperature through the respective heating elements 3 and 11, and after spraying the release agent, pour the semi-solid slurry into the concave mold 10, and then let the upper The mold is pressed down, and the guide post 8 enters the guide sleeve 9, which ensures the matching accuracy of the upper and lower molds. At the same time, the punch 2 is inserted into the die 10 to squeeze the semi-solid slurry, and gradually press the slurry back to the die. 10, when the punch 2 reaches the position, the excess semi-solid slurry overflows from the discharge trough 5 at the upper end of the die 10, and the remaining slurry is sealed in the die 18 by the front end of the upper pressing block 4 At this time, the spring 6 is still in a stretched state, which pre-presses the slurry. As the punch 2 is further pressed down, the spring 6 is compressed, the upper cover plate 1 and the punch 2 are in direct contact, and the slurry in the die 10 The pressure of the material increases rapidly until the lower end of the guide sleeve 9 is in direct contact with the upper surface of the lower mold frame 13, the pressure application process stops, and the pressure holding starts. Break out, the spring 6 recovers the state of free expansion, and the upper mold goes up to exceed the height of the piston casting, and then stops. Start the lower oil cylinder 21 of the extruder to move upward, push the unloading assembly to move upward, and eject the piston casting 22 through the ejector rod 20 . After that, without pouring the semi-solid slurry, the entire upper mold is pressed down in idling, contacts and pushes the reset rod 12 to move down, so that the unloading assembly is reset, the upper mold is moved up, and the paint is sprayed to prepare for the next extrusion. After several pistons are produced, the temperature of the punch and die rises, and the heating device stops heating.

Claims (6)

1, a kind of mould of semisolid extrusion casint all-aluminium piston comprises the counterdie of the patrix of being with punch and band die, and the discharge component of band knock-pin and release link, it is characterized in that being respectively equipped with heating member in the punch of patrix and on the die of counterdie.

2, the mould of semisolid extrusion casint all-aluminium piston according to claim 1 is characterized in that the heating member in the described patrix punch is an electrically heated rod, vertically is located at the punch middle part.

3, the mould of semisolid extrusion casint all-aluminium piston according to claim 1 is characterized in that the heating member on the described counterdie die is an electric heating wire, is around on the outer wall of die.

4, the mould of semisolid extrusion casint all-aluminium piston according to claim 1 is characterized in that the punch of described patrix is provided with upper holder block outward successively, goes up framed and guide pin bushing, and their top is provided with upper cover plate.

5, the mould of semisolid extrusion casint all-aluminium piston according to claim 1 is characterized in that the die of described counterdie is provided with low mold frame and guide pillar outward, and their below is provided with lower supporting plate, hollow cushion cover and lower shoe successively.

6, the mould of semisolid extrusion casint all-aluminium piston according to claim 1, the knock-pin and the release link lower end that it is characterized in that described discharge component all are fixed on the fixed head that is arranged in counterdie cushion cover vacancy, the upper end places respectively in the through hole of die and low mold frame correspondence, the fixed head below links to each other with the lower roof plate that is arranged in counterdie cushion cover vacancy, and lower roof plate links to each other with the extruder liftout tank.

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