KR100689168B1 - Method and apparatus for injection foaming molding - Google Patents

Abstract

A method for the injection foaming molding of a light alloy wherein a melt(2) of a light alloy containing a thickener and a blowing agent decomposing at a high temperature to generate a gaseous component in respectively specified percentages is held at a temperature lower than the decomposition temperature of the blowing agent and then is agitated to allow the thickener and the blowing agent to disperse, a predetermined amount of the melt is measured for the injection into a mold (24) and then is injected into the mold (24) to produce a foaming molded article of the light alloy, characterized in that the temperature of the melt (2) is adjusted to a temperature higher than the decomposition temperature of the blowing agent and also the foaming of the melt is inhibited by pressuring at least immediately before the injection; and an apparatus for practicing the method. <IMAGE>

Description

Injection foam molding method and injection foam molding apparatus {METHOD AND APPARATUS FOR INJECTION FOAMING MOLDING}

The present invention relates to an injection foam molding method and an injection foam molding apparatus for molding a molten light alloy to mold a foamed molded article.

What is shown below about the conventional manufacturing method of foam metal. As Method 1, there is one described in Japanese Patent Publication No. Hei 1-51528. This is caused by adding a thickener and a foaming material to the molten metal and stirring it, heating the temperature of the entire mold to a temperature equal to or higher than the melting point of the foaming metal, ending stirring to start foaming, and a large number of bubbles generated by decomposition of the foaming material by heat. Expands, releases the air in the mold to the outside, and the foam metal fills the entire inside of the mold to block the inside of the mold to keep the mold in a sealed state. One cell structure is formed and the foamed metal is cooled and solidified in the mold.

Also, as Method 2, there is one described in US Patent No. 2983597. This is a method in which a metal hydride is mixed with a molten metal to be decomposed and foamed by generation of hydrogen gas. In addition, the second alloyed molten metal is supplied from the screw in the middle while extruding the mixture of the metal hydride with the molten metal in the molten metal by the screw at a gas decomposition temperature or lower, and continuously foamed by generation of the decomposition gas. .

As Method 3, there is one described in Japanese Patent Laid-Open No. 2002-511526. This is a method of compressing the foaming material and the metal powder, heating the half finished material in the mold to foam it in the melting temperature range, and then cooling the obtained molded article.

As Method 4, there is one described in Japanese Patent Laid-Open No. 9-241780. This is a solution of the problem of adding a foaming material to the molten metal, generating hydrogen and foaming, and mixing the foaming material with metal powder and compression molding, and then heating and foaming in a mold. Titanium hydride having a weight ratio of 0.1 to 5% was added to the above metals, stirred, and uniformly dispersed. The molten metal was poured into the mold, the molten metal of the mold was reheated to 630 ° C. or higher, the molten metal was foamed, and then cooled and solidified. It is a method of obtaining a foaming metal.

However, the manufacturing method of the foaming metal of the above-mentioned methods 1-4 has the problem as shown below. In the method 1, since molten metal is heated and stirred in a mold, it requires time for heating and at the same time, since the same mold is used for cooling after foaming, there is a problem in productivity. In addition, in order to make a large molded article, a large mold is required, and in the case of a large mold, heating and cooling are as much as heat conduction heat transfer from the wall surface, and when further cooling, it is made of a metal having excellent heat insulating properties as a foam. Unnecessarily time consuming results.

In Method 2, it is possible to continuously form a metal body by foaming with hydrogen gas in the same manner as in Method 1, but in this method, there is no function to inject into a mold, and a molded article of a desired three-dimensional shape or a molded article of a complicated shape cannot be formed. . In addition, in order to maintain a constant mixing ratio of the molten metal and the foaming material such as titanium hydride and magnesium hydride, since only the screw rotation speed can be controlled, it is unstable, so that the supply amount of the foaming material cannot be maintained constantly, and the foaming rate is stable. It doesn't work. Therefore, there exists a problem that the nonuniformity of product quality (foam state) becomes large.

In the method 3, in order to obtain a uniform foamed body, it is necessary to mix powder uniformly, and to do so, it becomes time-consuming and expensive. Moreover, although it is possible to obtain a three-dimensional shaped article, there are problems that it is difficult to control the temperature and temporal control of foaming and melting of the metal powder by gas decomposition, and to obtain a foamed molded article having a uniform cell.

In Method 4, molding of a three-dimensional shape is possible, but since the molten metal is reheated to 630 ° C or higher in the mold as in the problem of Method 1, there is a problem in production efficiency due to time. In addition, it is necessary to raise the temperature of the mold to 630 ° C. or higher, which makes the mold expensive. In addition, when a large mold is used, it is difficult to control the temperature of the molten metal in the mold, and there is a problem that the variation in quality becomes large.

An object of this invention is to provide the injection foam molding method and injection foam molding apparatus of the light alloy which can make the difference of foaming state between each batch small, and have high productivity.

The injection molding method of the light alloy of the present invention holds a molten alloy of a light alloy containing a thickener and a foaming material decomposed at a high temperature to generate a gas component at a predetermined ratio, at a temperature below the decomposition temperature of the foaming material, and subsequently After the molten metal is stirred to disperse the thickener and the foaming material, a predetermined amount for injection into the mold is measured and injected into the mold to form a foamed molded body of the light alloy. At least immediately before the injection, the temperature is adjusted above the decomposition temperature of the foamed material, and foaming is suppressed in a pressurized state.

Since the thickening material and foaming material are added to a molten metal in predetermined | prescribed ratio previously, the difference of foaming state between each batch becomes small. In addition, although the foaming material is decomposed immediately before injection, since the volume in the metering portion is in a constant state, foaming of the molten metal is suppressed, and the molten metal is pressed. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

In addition, the injection molding method of the light alloy of the present invention is to hold a molten material and the molten alloy of the light alloy to which the gas-decomposed decomposition material is added at a predetermined ratio by a predetermined ratio at a temperature below the decomposition temperature of the foam material The molten metal is introduced into an injection molding apparatus having a stirring function, a weighing function, and an injection function, and the molten metal is stirred to disperse the thickener and the foam material, and then a predetermined amount for injection into the mold is weighed, and then injected into the mold. Injection molding of a light alloy to form a foamed molded article of a light alloy, wherein the molten metal is temperature-controlled above the decomposition temperature of the foamed material at least immediately before the injection, and foaming is suppressed in a pressurized state. will be.

The thickener and the foaming material are added to the molten metal in a predetermined ratio in advance, held at a temperature below the decomposition temperature of the foaming material, and then introduced into the injection molding apparatus and stirred in the injection molding apparatus. The difference in foaming state between batches becomes small. Moreover, although the foaming material decomposes just before injection, since the volume in a metering part is a fixed state, foaming of a molten metal is suppressed and a molten metal becomes a pressurized state. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

In addition, the injection molding method of the light alloy of the present invention is characterized in that the temperature of the molten metal is less than the decomposition temperature of the foamed material when the molten metal is stirred.

By keeping the temperature of the molten metal below the decomposition temperature of the foaming material during stirring, it is possible to uniformly disperse the foaming material in the molten metal without decomposition.

In addition, the injection molding method of the light alloy of the present invention is dispersed by stirring the melt of the light alloy to which a predetermined amount of thickener is added, dispersing the thickener, while supplying a predetermined ratio of an inert gas as a foaming material into the molten metal and stirring the inert gas. After dispersing the gas, a predetermined amount is measured to inject the molten metal into the mold, and the injection molding method of the light alloy to form a foamed molded body of the light alloy by injecting the molten metal, supplying at least the inert gas to the molten metal After that, the foaming is suppressed by being in a pressurized state until the injection is performed.

By melt-dispersing the molten metal to which the thickener is added, supplying a predetermined amount of inert gas into the molten metal, and stirring and dispersing it evenly with a screw, a foamed molded article having a substantially uniform cell structure can be formed. In addition, since the inside of the metering section is pressurized before injection is performed, foaming of the inert gas in the molten metal is suppressed. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

Moreover, the injection foam molding method of the light alloy of this invention is characterized in that the said pressurized state is produced by the pressing force which arises by performing the said stirring with a screw.

The thickener and the foamed material added in a predetermined amount to the molten metal are agitated and dispersed, and the inside of the weighing unit can be pressurized by a pressing force by a screw for discharging the molten metal to the front of the barrel. Therefore, foaming of the foaming material in a molten metal can be suppressed.

In addition, the injection molding method of the light alloy of the present invention is that the injection amount of the molten metal is reduced by the amount of foam relative to the mold content, and the pressure is released to foam the molten metal in the mold to obtain a molded foam. It is characterized by.

By injecting the molten metal into the mold by reducing the injection amount of the molten metal by the amount of foam, it is not necessary to perform mold opening at the time of foaming, and the size and shape of the foamed molded product can be precisely controlled.

In addition, the injection molding method of the light alloy of the present invention is injected by the injection amount of the molten metal in an amount equivalent to the mold content, and the foam is blown by releasing the pressurized state by opening the mold by the volume of the foamed powder. It is characterized by obtaining a foam molding.

Since the pressure is rapidly released by opening the mold at approximately the same time as the injection or after the injection, the molten metal can spread evenly to the details inside the mold to form a foamed molded article having a complicated shape.

In addition, the injection molding method of the light alloy of the present invention is temperature-controlled to below the decomposition temperature of the foamed material molten metal of the light alloy to which the thickening material and the foamed material that decomposes at a high temperature to generate a gas component by a predetermined ratio, the temperature is adjusted below The molten metal is supplied into a barrel provided with a screw that is rotatably and retractable, and the screw is rotated to stir the molten material to disperse the thickening material and the foamed material, and then, while the screw is rotated, the molten metal is retracted. It measures in the metering part formed in front, and heat-controls the said molten metal so that it may become more than the decomposition temperature of the said foam material at least immediately before injection, and the molten metal in the metering part whose volume is in a constant state by stopping retraction of the said screw. Pressurizes to suppress its foaming and advance the screw As to the injection of the molten metal into the mold it is characterized in that to obtain a molded foam article.

In the molten alloy of the light alloy to be supplied into the barrel, the thickener and the foaming material are previously added at a predetermined ratio, so that the thickener and the foaming material are uniformly dispersed in the kneading portion in the barrel. And since the molten metal is injected after measurement, the difference in foaming state between each batch becomes small. In addition, decomposition of the foam material occurs immediately before the injection, but the volume is brought to a fixed state by stopping the screw, and foaming of the molten metal is suppressed, and the molten metal is in a pressurized state. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

In addition, the injection molding method of the light alloy of the present invention is a light alloy by an injection foam molding apparatus having a barrel provided with a screw therein and a cylinder having a plunger therein, which communicates with the front through a communication flow path in the barrel. (A) a thickener and a foaming material which decomposes at a high temperature to generate a gas component are added at predetermined ratios, and the molten alloy of the light alloy held by adjusting the temperature below the decomposition temperature of the foaming material is held in the barrel; (B) a stirring step of dispersing the thickening material and the foaming material by stirring the molten metal by rotating the screw in the barrel; and (c) the plunger is retracted to move forward in the cylinder. A metering step of introducing and measuring the molten metal from the barrel through the communicating flow path to the metering unit generated; (d Pressurizing the molten metal by generating a gas component in a metered portion whose volume is constant by adjusting the temperature so that the molten metal is equal to or higher than the decomposition temperature of the foamed material at least immediately before injection, and stopping the retraction of the plunger. A pressurization step of suppressing the foaming in the state and (e) injection of the molten metal in which the foaming is suppressed in the pressurizing step is injected into the mold communicating with the inside of the cylinder from the front of the cylinder by advancing the plunger to foam molding. It consists of a foaming process.

The thickener and the foaming material are added to the molten metal in a predetermined ratio in advance, held at a temperature below the decomposition temperature of the foaming material, and then introduced into the injection molding apparatus and stirred in the injection molding apparatus. The difference in foaming state between batches becomes small. In addition, decomposition of the foam material occurs immediately before the injection, but the volume is brought to a fixed state by the stop of the plunger, the foaming of the molten metal is suppressed, and the molten metal is in a pressurized state. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

In addition, the injection molding method of the light alloy of the present invention is to hold a molten material and the molten alloy of the light alloy to which the gas-decomposed decomposition material is added at a predetermined ratio by a predetermined ratio at a temperature below the decomposition temperature of the foam material Injection molding of light alloy to stir the molten metal to disperse the thickener and foam material, and then to measure a predetermined amount for injecting the molten metal into a mold, and to inject the molten metal into a mold through an injection nozzle to form a light alloy foamed molded article. The molten metal is heated at least above the decomposition temperature of the foamed material at least immediately before the molten metal is injected into the mold.

Since the thickening material and foaming material are added to a molten metal in predetermined | prescribed ratio previously, the difference of foaming state between batches becomes small. In addition, since the injection molten metal is heated at least above the decomposition temperature of the foamed material at least immediately before injection into the mold, it is not necessary to reheat the mold above the decomposition temperature of the foamed material, and the cooling time of the mold is also shortened, thereby improving productivity.

In addition, the injection molding method of the light alloy of the present invention is characterized in that the molten metal is heated above the decomposition temperature of the foamed material when passing through the nozzle.

Since the thickening material and foaming material are added to a molten metal in predetermined | prescribed ratio previously, the difference of foaming state between batches becomes small. In addition, when the injection molten metal passes through the nozzle, the temperature is raised above the decomposition temperature of the foamed material, so that the mold does not need to be reheated above the decomposition temperature of the foamed material, and the cooling time of the mold is also shortened, thereby improving productivity.

The injection molding apparatus for light alloy of the present invention is supplied with a molten material and a light alloy of a light alloy to which a thick material and a foam material which decomposes at a high temperature to generate a gas component are supplied thereto, and the molten metal is rotatably provided by stirring means. A tubular member which is stirred to disperse the thickener and the foam member, and a metering unit which is installed in the tubular member so as to be retracted and withdrawn so as to cooperate with the tubular member at the tip of the tubular member to measure the molten metal, When the gas component is generated so that the movable member for injecting the molten metal in which the gas component is generated in the mold communicating with the metering portion and the molten metal in the state in which the metering is completed to hold the molten metal under pressure and suppress the foaming Hold the position of the movable member against an increase in the internal pressure of the cylindrical member of the It is characterized by including the position holding means.

According to such a structure, since what added the thickening material and foaming material to the molten metal previously in a predetermined ratio can be supplied to a cylindrical member, the difference of the foaming state between each batch becomes small. In addition, although the foaming material is decomposed immediately before the injection, the position holding means can hold the position of the movable member, and the volume of the metering portion in the cylindrical member can be kept constant so that foaming of the molten metal can be suppressed. The molten metal can be put in a pressurized state. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

Further, the light alloy injection foam molding apparatus of the present invention is characterized in that the position holding means is an electromagnetic valve capable of blocking the entry and exit of oil into the hydraulic cylinder provided in the hydraulic circuit of the hydraulic cylinder for advancing and moving the movable member.

According to such a structure, advancement of the movable member can be controlled easily. For this reason, the position of a movable member can be controlled according to the foaming state of a foam material, and it can make it easy to hold a molten metal in a pressurized state.

In addition, the injection molding apparatus of the light alloy of the present invention is characterized in that the movable member is composed of a stirring screw rotatable.

According to such a structure, it becomes possible to disperse | distribute the thickener and foam material in the molten metal supplied in the cylindrical member equally.

Further, the light alloy injection foam molding apparatus of the present invention comprises a barrel in which the tubular member stirs the molten metal, a cylinder connected to the molten metal to introduce and measure the stirred molten metal, and the movable member is provided in the cylinder. It is characterized by being a plunger.

According to such a structure, since what added the thickening material and foaming material to the molten metal in a predetermined ratio can be supplied to a cylindrical member, the difference of foaming state between each batch becomes small.

In addition, the injection molding apparatus for light alloy of the present invention is supplied with a thick material and a molten light alloy to which a foam material which decomposes at a high temperature to generate a gas component is supplied, and the molten metal is heated from below the decomposition temperature of the foam material to a decomposition temperature or more. A barrel having an adjustable temperature adjusting means and capable of generating a gas component therein by adjusting the molten metal to a temperature higher than the decomposition temperature of the foaming material by the temperature adjusting means; A screw configured to rotate the molten metal to disperse the thickener and the foamed material, and to retreat to cooperate with the barrel to form a metering portion at the tip of the barrel, and to advance the melt melted from the barrel into the mold by advancing; In the state of completion of weighing, To hold it, characterized in that against an increase in internal pressure of the barrel at the time when said gas component generated to suppress the foaming, which comprises a position holding means for holding the position of the screw in.

According to such a structure, the molten metal to which the thickener and foaming material were added previously can be supplied in a barrel, and it can be disperse | distributed reliably, and the difference of the foaming state for every injection becomes small. In addition, it is possible to easily adjust the temperature of the molten metal in the barrel, to control the state of the foamed material in the molten metal, and to make the difference in the foamed state between the respective batches smaller. In addition, the temperature can be adjusted so that the foam material is decomposed immediately before injection, and the volume of the metered portion in the barrel can be kept constant by means of the position holding means of the screw, so that foaming of the molten metal can be suppressed, and the molten metal is pressurized. You can do Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

In addition, the injection molding apparatus of the light alloy of the present invention is supplied with a molten metal and a light alloy of a light alloy to which a foam material which decomposes at a high temperature to generate a gas component is supplied, and the molten metal is temperature-controlled to be below the decomposition temperature of the foam material. A barrel including a temperature adjusting means and a screw rotatably provided therein to disperse the thickening material and the foamed material, and connected to the barrel to heat the melted temperature above the decomposition temperature of the foaming material. A cylinder having an adjustable second temperature adjusting means and a retractable portion installed inside the cylinder to retreat to cooperate with the cylinder at the tip of the cylinder to retreat and to advance the molten metal measured in the cylinder; The plunger to be injected into the mold from the And a position holding means for holding the position of the plunger against the increase in the internal pressure of the cylinder when the gas component is generated so as to hold the molten metal in a pressurized state and suppress the foaming. It is.

According to such a structure, the molten metal to which the thickener and foaming material were added previously can be supplied in a barrel, and it can be disperse | distributed reliably, and the difference of the foaming state for every injection becomes small. In addition, although the foaming material is decomposed immediately before the injection, the position holding means can hold the position of the movable member, and the volume of the metering portion in the cylindrical member can be kept constant so that foaming of the molten metal can be suppressed. The molten metal can be put in a pressurized state. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection to reach every corner of the mold, whereby the transferability of the mold is improved, and molding of a foamed molded article having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved. In addition, it is possible to accurately measure the molten metal by the cylinder. For this reason, the difference of the injection amount of the molten metal between each batch of injection molding becomes small, and a molded article can be formed with high precision.

In addition, the injection molding apparatus for a light alloy of the present invention is supplied with a molten alloy of a light alloy to which a thickening material and a foaming material which decomposes at a high temperature to generate a gas component are supplied thereto, and the stirring means is rotatably provided therein. By advancing the tubular member for stirring the molten metal to disperse the thickener and the foamed material, and the retractable part installed in the tubular member so as to retreat, the metering part for cooperating with the member to measure the molten metal is moved forward. And a movable member for injecting molten metal through an injection nozzle in a mold communicating with the metering unit, and nozzle heating means capable of raising the temperature above the decomposition temperature of the foamed material when the molten metal passes through the nozzle.

According to such a structure, the molten metal and foaming material which were added previously can be supplied in a barrel, and it can disperse | distribute it reliably, and the difference of foaming state for every injection becomes small. In addition, since the molten metal is injected through the injection nozzle, the injection pressure can be increased. In addition, since the foam is decomposed to generate gas components when the molten metal passes through the nozzle, i.e., just above the decomposition temperature of the foam just before injection into the mold, the melt is foamed at once in the mold immediately after injection, thereby foaming the mold temperature. There is no need to heat above the decomposition temperature of the ash, thereby improving productivity.

BRIEF DESCRIPTION OF DRAWINGS Fig. 1 is an overall explanatory diagram showing an example of an embodiment of an injection foam molding apparatus for a light alloy of the present invention.

FIG. 2 is an overall explanatory diagram showing an example of an embodiment of an injection foam molding apparatus for a light alloy of the present invention. FIG.

FIG. 3 is a diagram showing an essential part of an example of an embodiment of the light alloy injection molding apparatus of the present invention, and for explaining the molding process.

FIG. 4 is a diagram showing a main part of an example of an embodiment of the light alloy injection molding apparatus of the present invention, and for explaining the molding process.

FIG. 5 is a diagram showing an essential part of an example of an embodiment of the light alloy injection molding apparatus according to the present invention, and illustrating the molding process.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described based on drawing. 1 shows an example of an embodiment of the present invention. As shown in FIG. 1, the injection foam molding apparatus 1 which concerns on the example of this embodiment is comprised from the injection molding apparatus 3 and the mold clamping apparatus 17. As shown in FIG.

The injection molding apparatus 3 is provided with a supply port 8 through which a molten material of a light alloy to which a thick material and a foaming material which decomposes at a high temperature to generate a gas component is supplied, and a stirring means 4 rotatably provided. The cylindrical member A which stirs the molten metal supplied from (8), and disperse | distributes a thickening material and a foaming material, and a cylindrical member is provided in the front-end | tip of the cylindrical member A by retreating and being installed so that it can move forward and backward in this cylindrical member A. FIG. The movable member B which injects the molten metal which the gas component generate | occur | produced in the metal mold 24 which communicates with the metering part 6 by advancing and forming the metering part 6 which measures a molten metal in cooperation with (A), and Position to hold the position of the movable member B against the increase in the internal pressure of the cylindrical member A when the gas component generate | occur | produces in this completed state so that a molten metal can be hold | maintained in a pressurized state and the foaming can be suppressed. Find holding means (C) And. The barrel 7 for stirring the molten metal, which is the tubular member A, is provided with a temperature adjusting means 10 for controlling the temperature of the molten light 2 supplied to the molten alloy 2 and the molten light 2 supplied to the injection part 9. It is prepared. Moreover, the injection part 9 which injects the molten metal 2 measured by the measurement part 6 in the metal mold | die 24 is provided in the front-end | tip part of the barrel 7.

In addition, as shown in Fig. 1, since the barrel 7 is substantially vertical, the molten metal 2 of the light alloy supplied is reliably moved downward in the kneading section 5 by its own weight.

Moreover, the L-shaped flow path 11 is formed in the above-mentioned injection part 9, The flow path of the molten alloy 2 of light alloy is vertical at the time of kneading stirring, and horizontal at the time of injection. Therefore, even when the injection molding apparatus 3 and the mold clamping apparatus 17 are connected as shown in FIG. 1, the installation area of the injection foam molding apparatus 1 can be made as small as possible.

This injection foam molding apparatus 1 is provided with the nozzle part 13 provided with the valve means 12 in the front-end | tip of the L-shaped flow path 11 provided in the lower end part of the barrel 7. As shown in FIG. This tip portion is in contact with the mold 24 which slides horizontally by the mold clamping device 17 and opens and closes.

In addition, the hopper 14 of the structural members of the injection foam molding apparatus 1 receives the molten light alloy melted in the melting furnace which is not shown in figure, and stores it in a molten state, and the opening part of the lower end of this hopper 14 is the barrel 7 It is connected to the supply port 8 of the upper part of (). Moreover, the hopper 14 is provided with temperature control means, such as a heating heater. By this temperature control means, it becomes possible to control the molten metal 2 in the hopper 14 to a fixed temperature above the liquidus temperature and below the foaming temperature of a foam, or to control above the decomposition temperature of a foam. .

Moreover, the hopper 14 is equipped with the feeder for quantitatively supplying the thickening material and foaming material added to the molten alloy 2 of light alloy. By this feeder, powder thickener and foaming material can be quantitatively supplied to reduce the difference in foaming state between the batches. Moreover, you may supply the molten alloy of the light alloy which added the thickening material and foaming material the predetermined amount directly to the hopper 14.

In addition, a well-known thing, such as calcium, can be used for the thickener added to the molten alloy 21 of a light alloy. Well-known metal hydrides, such as titanium hydride, can be applied to a foam material. Titanium hydride produces gas decomposition around 640 ° C. In addition, the liquidus temperature in the case where the light alloy is an AL alloy is 630 ° C, and the liquidus temperature or more described later indicates 630 ° C or more, and the molten metal temperature is changed by the temperature adjusting means 10 of the barrel, for example, 630 ° C. By holding at 占 폚, the titanium hydride can be stirred and dispersed without decomposing.

In addition, the hopper 14 is filled with an inert gas 18 such as Ar supplied by the inert gas supply device 16, and the hot water surface of the molten alloy 2 of light alloy is filled with the inert gas 18. Is sealed. The position holding means C is provided in the upper end of the barrel 7 which is the cylindrical member A. As shown in FIG. This position holding means C is comprised by the drive motor 19 and the screw hydraulic cylinder 21 connected to this drive motor 19. As shown in FIG.

The drive shaft of this drive motor 19 is provided with a through-spline hole, and the spline shaft provided in the upper part of the screw 4 rotatably inserted in the barrel 7 is inserted, and the transmission of rotational drive force and It is adapted to allow the axial movement of the screw 4. ,

The upper part of the drive motor 19 is connected with the screw hydraulic cylinder 21 which has the cylinder rod 20 which retracts to an up-down direction. The screw 4 is connected to the cylinder rod 20 of this screw hydraulic cylinder 21, and the lower end part is arrange | positioned by the cantilever so that it may become a free end in the barrel 7. As shown in FIG. For this reason, the cylinder rod 20 of the screw hydraulic cylinder 21 is projected downward, and the stirring blade of the screw 4 is advanced (moved downward) via the drive motor 19 to the lower end in the barrel 7. The molten light 2 of the accumulated light alloy is passed through the L-shaped flow path 11 and can be injected into the mold 24 via the nozzle portion 13.

Moreover, the metering part 6 is formed in the lower part of the barrel 7 when the screw hydraulic cylinder 21 for this screw is operated and the screw 4 which is the movable member B is moved axially upward. This metering part 6 can be set suitably by the amount of retraction of the screw hydraulic cylinder 21 used as a capacity required for obtaining a molded article. In addition, the valve means 12 of the nozzle part 13 is in the closed state except at the time of injection. In addition, it is possible to apply the same thing to the valve means 12 mentioned later.

The outer peripheral surfaces of the barrel 7 and the injection part 9 are covered with the temperature adjusting means 10. The temperature adjusting means 10 is composed of a plurality of heating heaters separated in the vertical direction. And the temperature of the molten alloy 2 of the light alloy in the barrel 7 can be adjusted to at least 2 system by this heating heater. Thereby, temperature control can be performed in the up and down of the barrel 7, and the decomposition | disassembly of the foam material in the molten metal 2 can be controlled.

The mold clamping device 17 includes a link housing 26 mounted on the base 25, a fixing plate 28 fixed to the housing 26 via a tie bar 27 in a horizontal direction, and the fixing plate. The fixed mold 24b fixed to the 28, the movable panel 29 penetrated and slidably supported with respect to the tie bar 27, and the movable mold 29b slide to a horizontal direction with respect to the fixed mold 24b, and are movable so that opening and closing is possible. A moving mold 24a fixed to the cabinet 29 is provided. The mold clamping cylinder 30 is fixed to the center of the outer surface of the link housing 26, and the tip of the cylinder rod 31 of the mold clamping cylinder 30 is connected to the center of the movable plate 29. The link housing 26 and the movable panel 29 are connected to each other by a plurality of links 32 which are folded when they approach and are arranged in a substantially straight line in the horizontal direction.

An extrusion cylinder 33 is provided on a side of the movable housing 29 on the link housing 26 side, and the extrusion rod 34 of the extrusion cylinder 33 penetrates the movable cabinet 29 to move the mold 24a. Is connected to the product protruding mechanism. Accordingly, in the mold clamping device 17, the cylinder rod 31 of the mold clamping cylinder 30 is projected to extend the link 32 in a straight line, and the link 32 is tensioned. The moving mold 24a can be strongly pressed against the fixed mold 24b. In addition, mold release of the product is performed by projecting the extrusion rod 34 of the extrusion cylinder 33 to operate the product protrusion mechanism.

Since the molten alloy 2 of the light alloy is foamed at once in the mold 24 after the injection by the injection foam molding apparatus 1 as described above, the molten metal 2 extends to every corner of the mold 24 and is transferred to the mold 24. The properties are good, and the molding of a complicated molded foam can be achieved. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

Next, the operation | movement of the injection foam molding apparatus 1 which concerns on the example of this embodiment, and the injection foam molding method of the light alloy by it is demonstrated.

First, the molten alloy 2 of the light alloy introduced into the hopper 14 is transferred from a melting furnace (not shown) by means of a mechanical or electronic pump or the like. The melting furnace may be any kind, and a high frequency induction furnace or an electromagnetic induction furnace may be used. The molten alloy 2 of the light alloy in the hopper 14 is maintained at a uniform temperature by being temperature-regulated above the liquidus temperature and below the decomposition temperature of the foamed material by temperature control means such as a heating heater provided in the hopper 14. Further, the thickener and the foamed material are quantitatively supplied to the molten light 2 of the light alloy by a feeder (not shown) provided in the hopper 14. Thereby, the difference of foaming state between each arrangement can be made small. Moreover, the stirring means which stirs the molten metal 2 of the light alloy in the hopper 14 can be provided as needed, and agitation action can be given. In addition, oxidation of the molten metal can be prevented by providing the above-described inert gas supply device 16 in the hopper 14.

Next, the molten alloy 2 of the light alloy introduced into the hopper 14 is supplied to the upper portion of the barrel 7 in a gas-sealed state, and is heated to the liquidus temperature of the molten alloy 2 of the light alloy by a heating heater or higher. The temperature is adjusted and held below the decomposition temperature, and the screw 4 is rotated in the kneading section 5 in the barrel 7 to stir the molten light 2 of the light alloy to disperse the thickener and the foam. Therefore, the foamed material is powdery because the foamed material is kept below the foaming temperature during stirring, so that the foamed material can be uniformly dispersed.

In addition, when the molten metal 2 to which only the thickener is added is supplied into the barrel 7, the thickener is provided by installing an inert gas metering device (not shown) in the barrel 7 corresponding to the kneading section 5. At the time of stirring and dispersing, an inert gas which is a foam material is supplied to the molten metal so that the inert gas can be uniformly dispersed in the molten metal 2.

When stirring the molten metal 2 in the kneading part 5, when the molten alloy 2 of the light alloy is extruded downward in the barrel 7 by the extrusion force accompanying the rotation of the screw 4, A load is applied on the axial top. On the other hand, a constant back pressure is set in the screw hydraulic cylinder 21 constituting the position holding means, and when the internal pressure withstanding this back pressure occurs in the barrel 7, the predetermined position at which the screw 4 is set in accordance with the molded product volume Retreat by moving upward in the axial direction. And the molten metal 2 of the light alloy is measured by the metering part 6 between the screw 4 and the L-shaped flow path 11. In the present embodiment, the screw 4 retreats due to an increase in the internal pressure of the barrel 7 generated by the screw 4 while rotating, but the screw 4 stops rotation and retracts by the hydraulic cylinder 21 for the screw. May be any of those which are retracted by the screw hydraulic cylinder 21 while rotating. In addition, it is preferable to provide a backflow prevention means such as a check ring at the distal end of the screw 4, and by providing it, the metering part 6 according to the molded product volume while smoothly flowing the molten alloy 2 of the light alloy downward when retreating. ) Is weighed. In addition, at the time of metering, the nozzle part 13 of the L-shaped flow path 11 is closed by the valve means 12.                 

After the measurement is completed in this way, at least immediately before injection, the molten metal 2 is temperature-controlled so as to be heated up to the decomposition temperature of the foam material in the metering section 6 by a heating heater, and at the same time, the volume of the molten metal is stopped by stopping the retreat of the screw 4. The dissolution of the foamed material is promoted in the metering section 6 which is in a constant state, thereby bringing the molten metal 2 into a pressurized state and suppressing the foaming. Moreover, since the molten metal 2 can pressurize the inside of the metering part 6 by the extrusion force by rotation of the screw 4, it suppresses the foaming of the foamed material heated up to the decomposition temperature of the foamed material by the heating heater. It is possible.

And the molten metal 2 is injected into the metal mold 24 by opening the valve means 12 of the nozzle part 13, and advancing the screw 4, and the molten metal 2 in which foaming was suppressed was barrel 7 The molded article is molded by rapidly foaming in the mold 24 having a lower pressure than the one in the cylinder.

When the injection amount of the molten alloy 2 of the light alloy to be injected into the mold 24 is measured and injected at the same amount as the mold 24 content, when the injection into the mold 24 is carried out, the moving mold 24a is injected after injection. By opening by the volume of foaming powder, the pressure of a gas component is open | released at once, the molten metal 2 of light alloy is foamed in the slide direction, and the foamed molded object which foaming cell was uniformly disperse | distributed can be obtained. In addition, when the molten alloy 2 of the light alloy is injected into the mold 24, a skin layer is formed on the surface where the molten metal 2 and the mold 24 contact each other.

As such, the molten alloy 2 of the light alloy is injected into the mold 24, and the pressure of the gas component in which expansion is limited in the molten alloy 2 of the light alloy is rapidly increased by opening the mold 24 at approximately the same time as or after the injection. Since it is open, the molten metal 2 of the light alloy foamed to the detail inside the mold 24 is spread evenly enough to form a foamed molded article having a complicated shape.

In addition, when the injection amount of the molten alloy 2 of the light alloy to be injected into the mold 24 is reduced by the amount of foam relative to the volume of the mold (here, the molded article volume), the injection of the gas component at once in the mold 24 after injection is performed. The pressure is released, and the molten alloy 2 of the light alloy is foamed to obtain a foamed molded article in which the foamed cells are uniformly dispersed.

Thus, by reducing the injection amount of the molten alloy 2 of the light alloy to be injected into the mold 24 by the amount of foam, the size and the shape of the foamed molded body are not affected by the stopping accuracy and parallelism of the mold when the mold is opened. Can be controlled with high precision.

In the molten alloy 2 of the light alloy to be supplied into the barrel 7 by the injection foam molding method using the above-mentioned injection foam molding apparatus 1, since the thickener and the foaming material are added in a predetermined ratio, The fluctuation can be made small. Since the thickener and the foamed material are uniformly dispersed in the kneading portion 5 in the barrel 7, a molded article in which the foamed cells are uniformly dispersed can be obtained. Since it is injected in this way, the difference of foaming state between each batch becomes small.

In addition, immediately before injection, the foam material is decomposed to generate a gas component. However, the volume of the metering section 6 is fixed due to the stoppage of the screw 4, and thus the expansion of the melt (expansion of the gas component) is suppressed. The molten metal 2 of the light alloy can be filled to every corner of the mold 24 by opening and foaming the pressure in the mold 24 immediately after injection. Therefore, the transferability of the metal mold | die 24 becomes favorable, productivity improves, and the shaping | molding of foamed molded object of a complicated shape is also attained. In addition, by reducing the inside of the mold by a decompression means such as a vacuum pump, it is possible to further improve the transferability and formability of the foamed molded article having a complicated shape.

Next, another embodiment of the injection foam molding apparatus of the present invention will be described with reference to FIG. As shown in Fig. 2, in the injection foam molding apparatus 40 according to the embodiment, the injection section 9 of the injection foam molding apparatus 1 described above is a horizontal plunger type, and the barrel 7 is described above. Similarly, it consists of two members of the vertical shape.

FIG. 2 is an overall explanatory diagram showing an injection foam molding apparatus 40 for light alloy according to the embodiment. This injection foam molding apparatus 40 is a horizontal plunger type of the injection part 9 of the above-mentioned injection foam molding apparatus 1 as shown in FIG. 2, The barrel 7 and the mold clamping apparatus 17 are shown. ) Is approximately the same configuration as described above. In addition, the above-mentioned thing can be applied to the molten metal, foaming material, a thickening material, etc. of a light alloy.

This light alloy injection foam molding apparatus 40 has a supply port 58 to which a molten material 2 of light alloy, to which a thickening material and a foaming material which decomposes at a high temperature and generates a gas component, is added at a predetermined ratio. , A kneading portion 45 for agitating the molten metal 2 by means of a screw 44 provided to be rotatable and retracting therein to disperse the thickener and the foamed material, and a storage portion 46 formed by the screw 44 retreating. Can move back and forth along the axis of the cylinder 42 inside the cylinder 42 connected from the front via the barrel 47 having a stirring function composed of a) and the communication flow path 41 provided at the lower end of the barrel 47. With the plunger 48, the plunger 48 is retracted so that the metering portion 49 is formed in the front of the cylinder 42, and the plunger 48 is advanced to eject the molten alloy 2 of the light alloy, An injection molding apparatus 43 composed of a plunger injection machine 50 having an injection function, Plunger-type fastening with the mold (24) foaming the extruded molten metal (2) from the injector (50) and a device (17). Moreover, the temperature adjusting means 51 which controls temperature of the molten alloy 2 of the light alloy supplied from the supply port 58 into the barrel 47, and the molten alloy 2 of the light alloy supplied to the plunger injection machine 50 is provided.

Moreover, the nozzle part 52 provided with the valve means 12 is provided in the front-end | tip part of the plunger injection machine 50 of this injection foam molding apparatus 40. As shown in FIG. The distal end portion is in contact with the mold 24 which is slid horizontally by the mold clamping device 17 and opened and closed.

The hopper 53 of the structural member of this injection foam molding apparatus 40 uses the same thing as the hopper 14 mentioned above, and temperature control means, such as a feeder and a heating heater, is provided.

In addition, the structure of the barrel 47 is also the same structure as the injection foam molding apparatus 1 which concerns on the above-mentioned embodiment, and as shown in FIG. 2, the cylinder rod which advances and retreats to an up-down direction in the upper part of the drive motor 54 is shown. A screw hydraulic cylinder 56 having a 55 is connected, and a screw 44 is connected to the cylinder rod 55 of the screw hydraulic cylinder 56 via a drive motor 54. For this reason, the lower end part in the barrel 47 is made by protruding the cylinder rod 55 of the screw hydraulic cylinder 56 downward, and advancing (moving downward) the stirring blade of the screw 44 via the drive motor 54. FIG. The molten alloy 2 of the light alloy accumulated in the is supplied into the cylinder 42 of the plunger injection machine 50 via the communication flow passage 41.                 

Moreover, this screw hydraulic cylinder 56 is comprised so that the storage part 46 may be formed in the lower part in the barrel 47 when it moves to the axial direction upward. Moreover, it has a stroke enough to move the communication flow path 41 from the position which forms this storage part 46 to the position which can be closed.

As shown in FIG. 2, the outer circumferential surface of the cylinder 47 of the barrel 47 and the plunger injection machine 50 is covered with the temperature adjusting means 51. As shown in FIG. The temperature adjusting means 51 is composed of a plurality of separated heaters. By controlling this heating heater, at least the molten alloy 2 of the light alloy in the barrel 47 can be temperature-controlled below the decomposition temperature of the foamed material added thereto, and at least the molten alloy 2 of the light alloy in the cylinder 42. ), The foaming material added to this can be temperature-controlled beyond the temperature which produces | generates a gas component.

The plunger injection machine 50 is connected to the barrel 47 via the communication flow path 41 formed in the lower end part of the barrel 47. This plunger injection machine 50 has the cylinder 42 which has the nozzle part 52 provided with the valve means 12 in front, and the plunger 48 which can move back and forth inside the cylinder 42. As shown in FIG. The plunger 48 is driven by the hydraulic force of the hydraulic cylinder 57 for plunger. The metering part 49 is formed in the front part of the cylinder 42 when this plunger 48 retreats. The volume of this metering section 49 can be appropriately set by the amount of retraction of the plunger 48 so as to be the capacity required for obtaining a molded article. In addition, the plunger hydraulic cylinder 57 moves the communication flow path 41 connected near the distal end of the cylinder 42 to the position where the plunger 48 is advanced by moving forward from the position at which the metering section 49 is formed. Have enough strokes. Moreover, the plunger 48 is provided so that the communication flow path 41 may be closed when injection is completed. As a result, the molten alloy 2 of the light alloy for the next injection molding can be supplied into the barrel 47 immediately after the injection. In addition, the valve means 12 of the nozzle part 52 is in the closed state except at the time of injection | pouring. As the valve means 12, nozzle blocking may be used by a mechanical or spring shut-off valve provided at the nozzle tip.

By the injection foam molding apparatus 40 described above, at least immediately before injection, the gas component is generated in the molten metal 2 and the foaming of the molten metal 2 is suppressed. Since it can foam, since the molten metal 2 extends to every corner of the metal mold | die 24, the transfer property to the metal mold | die 24 becomes favorable, and productivity improves. In addition, molding of a foamed molded article having a complicated shape can be achieved. In addition, the maintenance of the apparatus can be easily performed by configuring the barrel 47 and the injection portion with two members.

Subsequently, an operation of the injection foam molding apparatus 40 according to the embodiment and a method of injection foam molding of the light alloy thereby will be described.

The molten alloy 2 of light alloy is thrown into the hopper 53 similarly from the above-mentioned melting furnace. Then, a thickening material and a foaming material which generates gaseous gas by gas decomposition at high temperature are added to the molten metal 2 at a predetermined ratio, and the decomposition temperature of the foaming material is not less than the liquidus temperature by the temperature control means of the hopper 53. Adjust the temperature to below. In this way, the supply stroke which supplies the molten metal 2 of the light alloy with temperature adjustment into the barrel 47 is performed. In addition, the thickener and the foaming material added to the molten metal 2 may be added to the hopper 53 by the feeder, or the molten material 2 to which the predetermined amount of the thickener and the foaming material are added to the hopper 53 may be added. good.

Next, the molten metal 2 is supplied to the upper part of the barrel 47, and by each temperature adjusting means 51, the molten metal 2 is temperature-controlled and held at or above the liquidus temperature and below the decomposition temperature of the foam material. In the mixing process 45 in the barrel 47, the screw 44 is rotated to uniformly disperse the thickener and the foam in the stirring step of stirring the molten metal 2. In addition, in the case where the molten metal 2 to which only the thickener is added is supplied into the barrel 47, an inert gas metering supply device (not shown) is provided to the barrel 47 corresponding to the kneading unit 45, thereby increasing the volume of the molten metal. When the point mixture is stirred and dispersed, the inert gas serving as the foaming material is supplied to the molten metal 2 at a predetermined ratio, so that the inert gas can be uniformly dispersed in the molten metal 2.

At this time, the plunger 48 of the plunger injection machine 50 is advanced to the position which closes the communication flow path 41, as shown in FIG. Then, by retreating while the screw 44 in the barrel 47 rotates, a reservoir 46 is formed between the screw 44 and the communication passage 41 instead of the metering portion 6 described above, and the reservoir ( First weigh in 46). At this time, the reservoir 46 is adjusted by the amount of retraction of the screw 44 so as to have a volume larger than the amount of molten metal to be injected. In addition, the screw 44 may stop revolving and retreat, or may retreat while rotating. In addition, it is possible to provide the above-mentioned countercurrent prevention means in the front-end | tip part of the screw 44. FIG.

Next, the communication flow passage 41 is opened, and the plunger 48 of the plunger injection machine 50 is retracted, and then from the barrel 47 via the communication flow passage 41 to the metering portion 49 generated in front of the cylinder 42. A metering stroke for introducing and measuring the molten metal 2 is performed. This metering stroke retracts the plunger 48 as shown in FIG. 4 and advances (moves downward) the screw 44 in the barrel 47. And the metering part which forms the molten alloy 2 of the light alloy in front of the cylinder 42, acting the pressing force by the screw 44, while retracting until the plunger 48 will be set to the predetermined position according to the molded product volume. The secondary measurement is performed by press-fitting while applying positive pressure to 49.

In this way, the thickener and the foaming material are previously added to the molten metal 2 at a predetermined ratio and held at a temperature below the decomposition temperature of the foaming material, and then introduced into the injection molding apparatus 43 and in the injection molding apparatus 43. By stirring, the thickener and the foaming material are uniformly dispersed, and the difference in foaming state for each injection becomes small.

Next, when the measurement by press-in is completed, the communication flow path 41 is closed by the screw 44 as shown in FIG. 5, and the back flow of the molten alloy 2 of the light alloy from the measurement part 49 is prevented. . In addition, the nozzle part 52 of the front-end | tip part of the cylinder 42 of the plunger injection machine 50 is closed by the valve means 12 at the time of a measurement.

In this way, after completion of the secondary metering, the temperature is adjusted by the respective temperature adjusting means 51 so that the molten metal 2 is equal to or higher than the decomposition temperature of the foamed material at least immediately before the injection, and the stop of the retraction of the plunger 48 is achieved. The pressurization step of suppressing the foaming is performed by bringing the molten metal 2 into a pressurized state by promoting decomposition in the metering section 49 where the volume is in a constant state. That is, as the temperature adjusting means 51 raises the molten alloy 2 of the light alloy to the temperature at which the foamed material decomposes in the metering section 49, the foamed material gradually starts decomposition to generate gas components, but the plunger 48 Since the increase in volume is suppressed by back pressure of), foaming of the molten metal 2 is suppressed in a pressurized state.

Next, the injection foam which injects and foams the molten metal 2 in which foaming is suppressed in a pressurization process in the metal mold 24 which communicates with the inside of the cylinder 42 in front of the cylinder 42 by advancing the plunger 48. A process is performed and molding of a molded object is performed.

In addition, when injecting into the mold 24, the injection amount of the molten light 2 of the light alloy to be injected into the mold 24 is measured and injected in the same amount as the mold 24 contents as in the above-described method, and the mold is foamed. The method of obtaining a foamed molded body by opening it, and the method of obtaining a foamed molded body in a fixed volume mold by injecting the injection amount of the molten light 2 of the light alloy to be injected into the mold 24 by the amount of foaming can be applied.

Although the foaming material decomposes | disassembles and gaseous component generate | occur | produces just before injection | pouring by the injection foam molding method using the above-mentioned injection foam molding apparatus 40, the volume is fixed by the stop of the plunger 48, and the molten metal 2 Since the foaming (expansion of gas components) is suppressed, the molten metal 2 extends to every corner of the mold 24 by opening and foaming the pressure in the mold 24 immediately after injection, thereby transferring the mold 24. The properties are good, and molding of a complicated molded foam can be achieved. In addition, as in the above-described embodiment, by depressurizing the inside of the mold by the decompression means, the transferability and the moldability of the foamed molded article having a complicated shape can be further improved.

In addition, in the case where a predetermined ratio of inert gas is supplied to the molten metal 2 as a foaming material by the inert gas metering supply device (not shown) using the injection foam molding apparatuses 1 and 40 as described above. Similarly, after stirring in the kneading sections 5 and 45 of the barrels 7 and 47 to disperse the inert gas, a predetermined amount is measured and injected into the mold 24 to inject the molten metal 2 into the mold 24. Injection When the temperature is raised by the temperature adjusting means 10 and 51 before the injection into the mold 24, the expansion of the gas component is promoted. However, in the injection foam molding apparatus 1, the injection foam molding apparatus 1 is stopped by the retraction stop of the screw 4. In 40, the increase in volume is suppressed by the retraction stop of the plunger 48, and in such a pressurized state, foaming of the molten metal 2 (expansion of gas components) is suppressed. The valve means 12 of the nozzle parts 13 and 52 are opened, and the screw 4 and the plunger 48 are advanced, and the molten alloy 2 of the light alloy is injected into the mold 24, thereby acting on the molten metal 2. Molding of the molded body is performed by opening and pressing the applied pressing force at once.

In this way, even when an inert gas is used for the foaming material, the inert gas is supplied into the molten metal 2 at a predetermined ratio and uniformly dispersed, so that the foamed molded article having a small uniform difference in foaming state for each injection can be formed. have.

The case where Ar gas is supplied from a barrel as a foam material using the injection foam molding apparatus 40 which provided the above-mentioned inert gas fixed-quantity supply apparatus in the barrel is further demonstrated.

As described above, a predetermined amount of thickener is added to the molten alloy 2 of the light alloy supplied from the melting furnace to the hopper 53. At this time, the temperature is adjusted above the liquidus temperature by the temperature control means of the hopper 53.

The thickening material is thus supplied by supplying the temperature-controlled molten metal 2 into the barrel 47 and stirring the molten metal 2 with the temperature adjusting means 51 at a temperature above the liquidus temperature by stirring in the kneading portion 45. Is dispersed. At this time, Ar gas is also disperse | distributed in the molten metal 2 by supplying high temperature Ar gas to the molten metal 2 from an inert gas quantity supply device (not shown). Subsequently, the molten metal 2 is sent out to the reservoir 46 at the lower portion of the barrel 47.

When the addition amount of the thickener added in the molten metal 2 sent to this storage part 46 is small, since the pressure of the molten metal 2 which arises by rotation of the screw 44 in the barrel 47 is small, a screw Pressure to withstand back pressure of 44 is not generated. In such a case, the screw 44 of the kneading part 45 is driven back in the axial direction of the screw hydraulic cylinder 56, and the molten metal 2 is transferred to the reservoir 46 by the weight of the molten metal 2. The pressure is sent to the metering section 49 of the plunger injection machine 50 by forwarding (moving downward) the screw 44, and then the molten metal 2 is transferred to the metering section 49 by the positive pressure. To be sent. Of course, when the addition amount of the thickener is large and the pressure which withstands the screw back pressure in the molten metal 2 by the rotation of the screw 44 generate | occur | produces, the drive by a cylinder is not necessarily required when sending the molten metal 2 to a storage part. not.

In addition, although the measured molten metal 2 is heated up by the temperature adjusting means 51 in the metering section 49 before injection, expansion of the Ar gas contained therein is promoted, but the volume of the molten metal is fixed by stopping the plunger 48. Since foaming is suppressed and foaming is suppressed, the pressure is opened and foamed in the mold 24 immediately after injection, so that the molten metal 2 extends to every corner of the mold 24, so that a foamed molded article in which the foamed cells are uniformly dispersed can be obtained. have.

Next, another embodiment of the injection foam molding apparatus of the present invention will be described. The injection foam molding apparatus which concerns on the example of this embodiment is the same apparatus structure except the point mentioned later with the injection foam molding apparatus 1 or injection foam molding apparatus 40 mentioned above. Therefore, description of the same point is abbreviate | omitted and only a different point is demonstrated.

This injection foam molding apparatus is configured to inject a molten light alloy containing a thickener and a foaming material that decomposes at a high temperature to generate a gas component, and is injected into a mold from an injection nozzle after being weighed. The nozzle heating means which can heat up the temperature of a molten metal above the decomposition temperature of foaming material is provided. Moreover, although well-known heating means, such as a resistance heating heater and an induction heating heater installed in the outer periphery of an injection nozzle, can be used for nozzle heating means, the induction heating heater which can shorten a temperature rising time is more preferable.

In addition, according to the injection foam molding method using the injection foam molding apparatus, a molten material in which a thickener and a foaming material are added in a predetermined ratio is prepared in the same manner as in the above-described embodiment, and the mixture is stirred to uniformly thicken the foaming material and the foaming material. Since it disperse | distributes, the difference of the foaming state for every injection becomes small.

In addition, the molten metal is temperature-controlled below the decomposition temperature of the foamed material at the time of metering, and foaming is suppressed, and the temperature is raised above the decomposition temperature of the foamed material at the time of passing through the injection nozzle immediately before injection into the mold. The gas component generated by decomposing the foaming material (immediately before injection into the mold) causes rapid foaming in the mold after injection. Therefore, it is unnecessary to reheat a mold beyond temperature decomposition of a foam material, and productivity becomes high.

Although the present invention has been described with reference to the embodiments as described above, the present invention is not limited to these forms and can be changed within a range not departing from the technical scope of the present invention.

For example, a shutter member may be provided in the hopper and the supply port portion of the barrel in continuous contact therewith to intermittently supply the molten metal from the hopper to the barrel. By doing in this way, addition of the predetermined ratio of the thickener and foaming material to the molten metal stored in the hopper can be performed easily.

In addition, in the injection foam molding method in the injection foam molding apparatus 40 according to the embodiment, the screw 44 is retracted and first weighed in the storage 46 formed in front of the barrel 47, and then By retracting the plunger 48 and advancing the screw 44 to the metering section 49 generated in the front of the cylinder 42, the molten metal 2 is introduced from the barrel 47 via the communication flow passage 41 to measure the Although it is performed, even if it is made to carry out metering by introducing the molten metal 2 into the metering part 49 which is produced by retracting the plunger 48, rotating without continuing to retract the screw 44 following stirring by the screw 44, good. This eliminates the need for the screw hydraulic cylinder 56, which simplifies the device configuration and eliminates the primary weighing operation.

In addition, pressure detection means such as a pressure gauge or a pressure sensor are provided in the hydraulic circuits of the screw hydraulic cylinders 21 and 56 and the plunger hydraulic cylinder 57, whereby the molten metal is heated up above the decomposition temperature of the foam material. The back pressure generated in the screw or plunger 48 may be detected. By doing in this way, the temperature rise state of the molten metal 2 or the decomposition state of foamed material can be estimated from the change of the back pressure accompanying the temperature rising of the molten metal 2.                 

In addition, by detecting a change in back pressure, the hydraulic cylinder can be pressure-controlled using this detected value as a control variable and used to control the foaming state of the molten metal 2. That is, the molten metal 2 is partially foamed before injection, the partially foamed molten metal 2 is pressurized, further foaming is suppressed, and the molten metal 2 is injected into the mold 24 to unfoamed portion. Can be controlled so that the molten metal 2 before injection (when weighing) is in a desired foaming state in the case of performing control to rapidly foam the mold 24. The molten metal 2 may be partially foamed by the position control of the hydraulic cylinder regardless of the pressure control of the hydraulic cylinder.

In addition, although this invention is described in the above-mentioned preferable embodiment, this invention is not limited only to it. It will be understood that various other embodiments may be made without departing from the spirit and scope of the invention.

In the injection foam molding method and the injection foam molding apparatus of the present invention, since the molten metal is at least temperature-controlled above the decomposition temperature of the foam material at least immediately before injection, and foaming is suppressed in a pressurized state, the difference in the foaming state between the batches Becomes smaller. In addition, although the foaming material is decomposed immediately before injection, since the volume in the metering portion is in a constant state, foaming of the molten metal is suppressed, and the molten metal is pressed. Therefore, the molten metal is foamed by releasing pressure at once in the mold immediately after injection, so that the mold is transferred to every corner of the mold, so that the transferability of the mold is improved, and molding of a molded foam having a complicated shape is possible. In addition, since the mold temperature does not need to be heated above the decomposition temperature of the foam material, productivity is improved.

Claims (23)

The molten alloy containing the thick material and the foamed material which decomposes at a high temperature to generate a gas component at a predetermined ratio is held at a temperature below the decomposition temperature of the foamed material, and then the molten material is stirred to form the thickened material and the foamed material. After dispersing, a predetermined amount for injection into the mold is measured, and the injection molding method of light alloy to form a molded foam of light alloy by injection into the mold, The molten alloy is temperature-controlled above the decomposition temperature of the foam material immediately before the injection, and foaming is suppressed in a pressurized state, characterized in that the injection molding molding method of light alloy. 2. The injection foam molding method for light alloy according to claim 1, wherein the molten metal is introduced into an injection molding apparatus having a stirring function, a metering function, and an injection function, and the molten metal is stirred. The injection foam molding method for light alloy according to claim 1, wherein the temperature of the molten metal is less than the decomposition temperature of the foamed material when the molten metal is stirred. 3. The injection foam molding method for light alloy according to claim 2, wherein the temperature of the molten metal is lower than the decomposition temperature of the foamed material when the molten metal is stirred. After dissolving the thickener by stirring a molten light alloy to which a predetermined amount of thickener is added, dispersing the inert gas while supplying a predetermined ratio of an inert gas as a foaming material in the molten metal, and then injecting the molten metal into a mold. In order to measure a predetermined amount, and injected into the mold to form a molded foam of the light alloy is a light alloy injection foam molding method, The foaming is suppressed by supplying the molten metal to the pressurized state after supplying the inert gas until the injection is carried out. The injection foam molding method for light alloy according to claim 5, wherein the pressurized state is caused by a pressing force generated by performing the stirring with a screw. The injection molding of the light alloy according to claim 1, wherein the injection amount of the molten metal is reduced by the amount of foam relative to the mold content, and the molten metal is foamed inside the mold to release the pressurized state to obtain a foamed molded body. Foam molding method. The injection of the light alloy according to claim 2, wherein the injection amount of the molten metal is injected by reducing the amount of foam to the mold content, and the molten metal is foamed inside the mold to release the pressurized state to obtain a foamed molded body. Foam molding method. The injection of the light alloy according to claim 5, wherein the injection amount of the molten metal is injected by reducing the amount of foam to the mold content, and the molten metal is foamed inside the mold to release the pressurized state to obtain a foamed molded body. Foam molding method. 2. The foamed molded product according to claim 1, wherein the injection amount of the molten metal is injected in an amount equal to the mold content, and the foamed product is obtained by foaming the molten metal by opening the mold by the volume of the foamed powder and leaving the pressurized state. Injection foam molding method of light alloy. The foamed molded product according to claim 2, wherein an injection amount of the molten metal is injected in an amount equivalent to a mold content, and the molten metal is foamed by opening the mold by the volume of the foamed powder and leaving the pressurized state to obtain a foamed molded article. Injection foam molding method of light alloy. 6. The foamed molded product according to claim 5, wherein the injection amount of the molten metal is injected in an amount equal to the mold content, and the mold is opened by the volume of the foamed powder to release the pressurized state to foam the molten metal to obtain a foamed molded article. Injection foam molding method of light alloy. The molten alloy of the light alloy to which the thickening material and the foaming material which generate | occur | produces a gas component by decomposing at high temperature is added by the predetermined ratio is temperature-controlled below the decomposition temperature of the said foaming material, and the screw is provided so that the said molten metal can rotate and retreat. After supplying into the barrel and stirring the molten metal by rotating the screw to disperse the thickening material and the foamed material, and retreating while rotating the screw, the molten metal is metered in a metering section formed in front of the barrel, and immediately before injection. The temperature of the molten metal is adjusted to be equal to or higher than the decomposition temperature of the foamed material, the retreat of the screw is stopped, and the molten metal is kept in a pressurized state in a metered portion in which the volume is in a constant state. Injecting the molten metal into a mold by advancing a screw to obtain a foamed molded article Injection foam molding method of light alloy, characterized in that. It is an injection foam molding method of light alloy by the injection foam molding apparatus which has the barrel provided with the screw inside, and communicates from the front via the communicating flow path in the said barrel, and the cylinder provided with the plunger inside, (a) a supplying step in which a thickening material and a foaming material which decomposes at a high temperature to generate a gas component are added at predetermined ratios, and a molten light alloy held in a temperature controlled temperature below the decomposition temperature of the foaming material is supplied into the barrel; (b) a stirring step of dispersing the thickener and the foamed material by stirring the molten metal by rotating the screw in the barrel; (c) a metering step of introducing the molten metal from the barrel through the communication flow path to the metering section where the plunger is retracted and is generated in front of the cylinder; (d) The molten metal is temperature-controlled to be equal to or higher than the decomposition temperature of the foamed material immediately before injection, and the retreat of the plunger is stopped to generate a gas component in a metered portion whose volume is in a constant state to pressurize the molten metal. A pressurization step of suppressing the foaming in a state; (e) An injection foam molding method for a light alloy, comprising: an injection foaming step of injecting a molten metal in which foaming is suppressed in the pressurizing step into a mold communicating with the inside of a cylinder from the front of the cylinder by advancing the plunger and foaming the foam. The molten alloy of the light alloy to which the thickening material and the foaming material which generate | occur | produces a gas component by decomposing at high temperature is added is hold | maintained at the temperature below the decomposition temperature of the said foaming material, and the said molten metal is stirred, and the said thickening material and foaming material are disperse | distributed And then, a predetermined amount for injecting the molten metal into the mold, and then injected into the mold through an injection nozzle to form a light alloy foamed molded article, which is an injection foam molding method of light alloy. Just before the molten metal is injected into the mold, the injection molding method of the light alloy, characterized in that the temperature is raised above the decomposition temperature of the foam. 16. The injection foam molding method for light alloy according to claim 15, wherein the molten metal is heated above the decomposition temperature of the foam when passing through the nozzle. The molten material and the light alloy of the light alloy which added the foaming material which generate | occur | produces a gas component by decomposing at a high temperature inside are supplied, and the said thickening material and foaming material are disperse | distributed by stirring the molten metal according to the stirring means rotatably installed in the inside. With cylindrical member to let you, The molten metal which is installed so as to be able to move forward and backward in the tubular member, and is retracted, forms a metering portion for measuring the molten metal in cooperation with the tubular member at the tip of the tubular member, and advances to the molten metal in which a gas component is generated in the mold communicating with the metering portion. A movable member for injecting Holds the position of the movable member against the increase in the internal pressure of the cylindrical member when the gas component is generated so that the molten metal is held in a pressurized state and the foaming can be suppressed in the state where the measurement is completed. An injection foam molding apparatus for light alloys, comprising: support means. 18. The injection foam molding apparatus for light alloy according to claim 17, wherein the position holding means is an electronic valve capable of blocking entry of oil into a hydraulic cylinder provided in a hydraulic circuit of a hydraulic cylinder for advancing and moving the movable member. 18. The injection molding apparatus for light alloy according to claim 17, wherein the movable member is made of a rotatable stirring screw. 18. The cylindrical member according to claim 17, wherein the tubular member comprises a barrel for stirring the molten metal and a cylinder connected to the molten metal for introducing and measuring the stirred molten metal, wherein the movable member is a plunger provided in the cylinder. Injection foam molding apparatus of light alloy. The molten alloy of the light alloy to which the thickening material and the foaming material which generate | occur | produces a gas component by decomposing at high temperature is added is supplied, and it has the temperature control means which can adjust the molten metal from the decomposition temperature of the said foaming material to the decomposition temperature or more, and said melt A barrel capable of generating a gas component therein by adjusting the temperature of the foamed material to a temperature higher than the decomposition temperature by the temperature adjusting means; Rotating and retracting is installed inside the barrel so as to rotate and stir the molten metal to disperse the thickener and foam material, and retreat to form a metering unit in cooperation with the barrel at the tip of the barrel, and to advance the molten metal measured by advancing. A screw configured to inject into the mold from the barrel, Position holding for holding the position of the screw against the increase in the internal pressure of the barrel when the gas component is generated so that the molten metal is held in a pressurized state and the foaming can be suppressed in the state where the metering is completed. Injection molding apparatus for light alloy, characterized in that it comprises a means. The molten alloy of the light alloy to which the thickening material and the foaming material which generate | occur | produces a gas component by decomposing at high temperature is added, is supplied, and it has a 1st temperature adjustment means which can temperature-control below the decomposition temperature of the said foaming material, and is rotatably installed inside. A barrel for stirring the molten metal with a screw to disperse the thickener and the foamed material; A cylinder having second temperature adjusting means connected to the barrel and capable of adjusting the molten metal above the decomposition temperature of the foamed material; A plunger installed in the cylinder so as to be retracted and retracted so as to cooperate with the cylinder at the tip of the cylinder to measure the molten metal, and to advance the plunger to inject the measured molten metal from the cylinder into the mold; Position holding means for holding the position of the plunger against the increase in the internal pressure of the cylinder when the gas component is generated so that the molten metal can be held in a pressurized state and the foaming can be suppressed in the state where the metering is completed. Injection molding apparatus for light alloys, characterized in that it comprises a. The molten material and the light alloy of the light alloy to which the foaming material which decomposes at high temperature and generate | occur | produces a gas component are added to the inside, and the said molten material is stirred by the stirring means rotatably provided therein, and the said thickening material and foaming material are removed. A cylindrical member to disperse, The movable member which is installed so as to be able to move back and forth in the tubular member and withdraws, forms a metering unit for measuring the molten metal in cooperation with the member at the tip of the tubular member, and moves forward to inject the molten metal through the injection nozzle into the mold communicating with the metering unit. Wow, An injection molding apparatus for light alloys, comprising: nozzle heating means capable of raising a temperature above the decomposition temperature of the foamed material when passing the molten metal through the nozzle;

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