JP2003164960A - Casting device, supplying device for material of molten metal and method for supplying material of molten metal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To be able to shorten a casting cycle in a device and a method capable of melting and supplying a required amount of metal material for each casting. <P>SOLUTION: The device is provided with a material supply mechanism 851 supplying a metal material at each one casting to a container 330 for melting the metal material located on the fixed position against a sleeve 360. This material supply mechanism 851 has a storage section 60 storing the metal material, a measuring section 70 feeding the metal material by the amount required for one-time casting from the storage section 60, a gas supply source 66 supplying an inert gas to the storage section 60 to place the metal material under the inert gas atmosphere, and a gas heating device 930 heating the inert gas supplied from the gas supply source 66 to previously heat the stored metal material into the temperature within a range where the metal material is not molten. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten metal supply apparatus and method applied to a casting apparatus such as a die casting machine.

[0002]

2. Description of the Related Art The supply of molten metal to a sleeve of an injection device in a conventional die casting machine is performed by, for example, pumping a sufficient amount of metal material previously melted in a melting furnace by using a ladle to pump a required amount for casting. Is carried to the hot water supply port of the sleeve.

[0003]

By the way, when the molten metal is supplied by the above method, the melting furnace melts a large amount of metal and thus has a large surface area. Therefore, the thermal efficiency due to the release of heat to the atmosphere is high. However, there was a disadvantage that the required cost increased due to such reasons as the decrease in temperature and the need to maintain heat in the molten state at all times. Further, there is a disadvantage that the molten metal may be scattered during the transportation of the molten metal by the ladle, and the environment of the site where the die cast product is manufactured is likely to be deteriorated. Further, when not all the metal melted in the melting furnace is used for casting, there is a disadvantage that the electric power cost required for melting is wasted. Further, when the metal material is melted and conveyed in the atmosphere, it is likely to solidify due to heat dissipation and to be easily oxidized, so that there is a disadvantage that the quality of the die cast product is likely to be deteriorated. On the other hand, Japanese Patent Publication No. 59-38867 discloses a technique of melting a sufficient amount of metal material for one casting and supplying it to a sleeve instead of melting a sufficient amount of metal material in the above melting furnace. It is disclosed. The technique disclosed in Japanese Patent Publication No. 59-38867 discloses that a powder or granular metal material is provided in a plurality of crucibles, which is melted by induction heating, and is conveyed to a hot water supply port of a die casting machine and injected. Is. However, in the above technique, since the melting of the metal material is performed for each casting, the time required for one melting has a great influence on the time of the casting cycle, and the shortening of this melting time is a major factor in improving productivity. It was a challenge.

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a molten metal supply device for melting and supplying a required amount of metal material for each casting, and performing the casting. It is an object of the present invention to provide a molten metal supply apparatus and method capable of shortening the melting time of a metal material in the method and improving productivity. Still another object of the present invention is to provide a molten metal supply apparatus and method capable of suppressing the deterioration of the quality of cast products due to the oxidation of metal materials.

[0005]

The molten metal supply apparatus of the present invention is a molten metal supply apparatus which melts and supplies a metal material to a casting apparatus for each casting, and the molten metal supply apparatus is a predetermined apparatus for the casting apparatus. In the container for melting the metal material arranged at the position of, having a material supply means for supplying the metal material for each casting, the material supply means, a storage portion for storing the metal material, A metering unit that sends out an amount of a metal material required for one casting from the accumulating unit, a gas supply unit that supplies an inert gas to the accumulating unit and places the metal material in an inert gas atmosphere, And a gas heating unit that heats the inert gas supplied to the storage unit by the gas supply unit to preheat it to a temperature that does not melt the metal material stored in the storage unit.

[0006] Preferably, the material supplying means holds the metal material sent from the measuring section releasably until it can be supplied to the container, and the metal held by the temporary holding section. And heating means for heating the material.

In the molten metal supply method of the present invention, the metal material accumulated in the accumulating portion is weighed for each casting, and a required amount of the metal material is placed in a predetermined position with respect to the casting apparatus. A molten metal supply method for supplying a molten metal in the container to a molten metal by heating and melting the metallic material in the container, and supplying the molten metal in the container to the casting apparatus. At the same time, the inert gas is heated to a temperature in a range in which the metal material accumulated in the accumulating portion is not melted.

Preferably, each time the metal material supplied to the container is supplied to the container, the metal material is temporarily held in a temporary holding unit provided between the accumulation unit and the container,
The metal material is further heated by the temporary holding unit until it is ready to be supplied to the container, and is supplied to the container.

The casting apparatus of the present invention is a material for supplying a metallic material to a casting apparatus main body and a container arranged at a predetermined position with respect to the casting apparatus main body for melting the metallic material for each casting. The material supply means includes a storage part for storing the metal material, a metering part for sending out the metal material in an amount necessary for one casting from the storage part, and a storage part for storing the metal material. A gas supply means for supplying an active gas to place the metal material in an inert gas atmosphere, and a metal accumulated in the accumulation part by heating the inert gas supplied to the accumulation part by the gas supply means. And a gas heating means for preheating the material to a temperature within a range that does not melt it.

[0010] Preferably, the material supplying means holds the metal material sent from the measuring section releasably until it can be supplied to the container, and the metal held by the temporary holding section. Heating means for heating the material.

In the present invention, the heated inert gas is supplied to the metal material stored in the storage section to heat the metal material. As a result, the preheating of the metal material and the prevention of oxidation are simultaneously performed. Further, in the present invention, the required amount is measured from the metal material accumulated in the accumulation part, and the metal material after the measurement is temporarily held and then put into the container. At this time, if the temperature of the metal material before weighing is too high, it will be softened, so that weighing cannot be performed properly. Therefore, in the present invention, the metal material is heated to a relatively low temperature before weighing, and the temporarily held metal material after weighing is heated to a relatively high temperature. With such a configuration, it is possible to appropriately measure the metal material and reduce the time required for melting the metal material supplied to the container. Further, by heating the metal material in advance before temporarily holding it, the metal material can be quickly heated to a desired temperature in the temporary holding portion.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the structures of a casting apparatus and a molten metal supply apparatus according to an embodiment of the present invention. In FIG. 1, the molten metal supply device 1 is
It has a container 330 and a material supply mechanism 851.

The container 330 is arranged at a predetermined position with respect to the hot water supply port 360h of the sleeve 360 of the die casting machine body (not shown). An RF coil 350 for melting is provided on the outer periphery of the container 330. Container 330
Has an opening 330h at the bottom.
30h is opened and closed by a lid 340 provided on the container 330. A required amount of metal material is supplied to the container 330 from the material supply mechanism 851 for each casting. The metal material supplied to the container 330 is melted by induction heating by supplying a high frequency current to the melting RF coil 350. Container 3
The molten metal in 30 is supplied to the sleeve 360 of the die casting machine by opening the lid 340. Container 33
0 is formed of a heat resistant material such as ceramics.

The material supply mechanism section 851 includes a storage section 60,
The measuring unit 70, the buffer unit 80, the introducing unit 90, the preheating RF coil 650, the gas supply source 66, and the gas heating device 930 are included. The material supply mechanism section 851 is an embodiment of the material supply means of the present invention.

The accumulating portion 60 accumulates the metal material before melting and supplying. The storage unit 60 includes a hopper 61 and a lid 62. The hopper 61 has a conical outer shape and has a space for accommodating the metal material M therein. The upper end of the hopper 61 has a circular opening, and the lower end has a supply port 61a for feeding the metal material M. In addition, the hopper 61 has a support member 6 fixed to the upper surface of the support base 300.
A fixing member 6 for fixing the outer periphery of the lower end portion of the hopper 61 to 9c.
It is fixed by 9a and 69b. The metal material M accumulated in the hopper 61 is, for example, a long and thin granular metal such as an aluminum alloy or a magnesium alloy used for casting.

The lid 62 has a peripheral wall portion 63 on the outer peripheral edge of a circular metal plate, and the peripheral wall portion 63 is fitted on the outer periphery of the upper end of the hopper 61 to cover the opening at the upper end of the hopper 61. A ring-shaped seal member 62a is provided on the inner periphery of the peripheral wall portion 63 of the lid 62 to seal between the outer peripheral surface of the upper end of the hopper 61 and the inner peripheral surface of the peripheral wall portion 63. The opening at the upper end of the hopper 61 is sealed by the sealing member 62a.

A remaining amount detector 64 is provided at a substantially central portion of the lid 62.
And a gas introduction pipe 65. Remaining amount detector 6
4 is connected to the sensor amplifier 67, for example,
The distance L between the upper surface of the metal material M housed in the hopper 61 and the remaining amount detector 64 is detected in a non-contact manner, and a detection signal is output to the sensor amplifier 67. As the remaining amount detector 64, for example, a length measuring sensor using light, ultrasonic waves, or the like can be used.

The gas introducing pipe 65 is an inert gas G such as nitrogen gas or argon gas supplied from a gas supply source 66 provided outside the hopper 61 via a gas heating device 930.
Is introduced into the hopper 61. The inert gas G is supplied into the hopper 61 in order to prevent the metal material M contained in the hopper 61 from being oxidized. The inert gas G supplied into the hopper 61 is supplied through the supply port 61a at the bottom of the hopper 61,
It is introduced into the weighing unit 70, the buffer unit 80, and the introduction unit 90.

The gas supply source 66 supplies an inert gas G such as nitrogen gas or argon gas. Gas heating device 930
Heats the inert gas G supplied from the gas supply source 66 and supplies it to the storage unit 60. By heating the inert gas G by the gas heating device 930, the metal material M accumulated in the accumulation unit 60 is placed in the heated inert gas atmosphere, and thus the temperature of the metal material M also rises. At this time, the temperature at which the gas heating device 930 heats the inert gas G is a temperature at which the metal material M stored in the storage unit 60 is not softened.

The temperature of the metallic material M accumulated in the accumulating section 60 is appropriately selected according to the type. When the metallic material M is, for example, an aluminum alloy or a magnesium alloy, 100 ° C. to 300 ° C. It is a range of degrees. This is because aluminum alloys and magnesium alloys do not soften at such temperatures. The reason why the metal material M is not softened is that if the metal material M stored in the storage unit 60 is softened, the metal material M cannot be appropriately supplied to the weighing unit 70, and the weighing unit 70 can perform accurate weighing. This is because there is a possibility that it cannot be performed. That is, it is preferable to heat the metal material M to a temperature at which it can be appropriately conveyed and measured.

The weighing section 70 has a supply port 61a of the hopper 61.
A required amount of the metal material M sent out by its own weight is weighed and sent to the buffer section 80. This weighing unit 70
Is a cylinder 71 supported substantially horizontally by the support member 69c and the screw 7 inserted in the cylinder 71.
4 and.

The cylinder 71 has a supply port 61 of the hopper 61.
It has an opening 71a for communicating a with the inside of the cylinder 71. The metal material M is supplied into the cylinder 71 from the hopper 61 through the opening 71a.

The screw 74 is composed of a spirally formed member, the free end of which is the front end and the rear end of which is
A shaft member 73 rotatably held by a bearing BR held by a support member 69c via a flange member 77.
Are linked to. This shaft member 73 is a coupling 75.
Is connected to the rotary shaft 76a of the servomotor 76 via.

The servo motor 76 is fixed to the support member 69c and is connected to the servo driver 79.
The servo driver 79 receives a control command from an external controller (not shown) and controls the rotation of the servo motor 76.

When the screw 74 is rotated in a predetermined direction, the metal material M supplied in the cylinder 71 is conveyed and delivered to the buffer section 80 through the opening at the tip of the cylinder 71. The carry amount of the screw 74 is determined according to the rotation amount of the screw 74.

Therefore, in the measuring section 70, the control is instructed to the servo driver 79 to rotate the screw 74 which conveys the metal material M in an amount required for casting, thereby performing the measurement.

The buffer section 80 temporarily holds the metallic material sent from the weighing section 70. This buffer section 8
Reference numeral 0 denotes a cylindrical member 81 connected to the support member 69c by a connecting member 78, an air cylinder 82 for expanding and contracting the piston rod 83 inserted in the cylindrical member 81, and a valve body connected to the tip of the piston rod 83. 84.

The cylindrical member 81 has an accommodation space 81s for accommodating the metal material M sent out from the weighing section 70 therein. The opening on the upper end side is closed by the closing member 85, and the inside of the opening 81a on the lower end side. The valve seat surface 81 of the valve body 84 around the circumference
b.

The air cylinder 82 is fixed to the closing member 85, and the piston rod 83 of the air cylinder 82 is inserted into the cylindrical member 81 through the through hole 85a formed in the closing member 85. The air cylinder 82 is connected to an air source 87 via a control valve 86.

The control valve 86 receives the control command from the external control device and controls the supply of the compressed air supplied from the air source 87 to the air cylinder 82 so that the piston rod 83 moves in the directions of arrows K1 and K2. Drive.

The valve element 84 is made of a conical member and has a tapered surface 84a that matches the valve seat surface 81b. The taper surface 84a of the valve element 84 is seated on the valve seat surface 81b when the piston rod 83 moves up in the direction of arrow K1 by the driving of the air cylinder 82. Thereby, the cylindrical member 8
The opening 81a on the lower end side of 1 is closed. When the metal material M is supplied from the measuring unit 70 in a state where the opening 81a on the lower end side of the cylindrical member 81 is closed, the metal material M falls from the tip of the cylinder 71 into the accommodation space 81s, and the metal material M It is held in the accommodation space 81s. Tapered surface 84 of valve body 84
When the piston rod 83 descends in the direction of arrow K2, a is separated from the valve seat surface 81b, and a gap is formed between the tapered surface 84a and the valve seat surface 81b. In the state where the metal material M is held in the accommodation space 81s, the metal material M falls downward of the cylindrical member 81 by its own weight through this gap.

The introduction section 90 has an introduction tube 91 for guiding the metal material M released from the buffer section 80 and falling by its own weight to the container 330. The introduction pipe 91 is a cylindrical member 81.
Is connected to the lower end of, for example, by welding,
The connection between the lower end of the cylindrical member 81 and the introduction pipe 91 is sealed.

The preheating RF coil 650 heats the metal material M, which is weighed and held in the buffer section 80, in a temperature range that does not melt. Specifically, the metal material M is heated in a temperature range below the solidus line. For example, aluminum alloy or magnesium alloy is heated to about 400 ° C. By supplying the preheated metal material M to the container 330, it is possible to shorten the time until the metal material M is melted into the molten metal ML in the container 330.

FIG. 2 is a diagram showing an example of a current supply system for supplying a current to the preheating RF coil 650. As shown in FIG. 2, the preheating RF coil 650 is connected to the induction heating power source 670 via the switching circuit 660, and the melting RF coil 350 is also connected to the induction heating power source 670 via the switching circuit 660.

The switching circuit 660 selectively switches the current supplied from the induction heating power source 670 to the preheating RF coil 650 or the melting RF coil 350 in accordance with a control command from the control device 400.

Next, an example of the order of current supply to the preheating RF coil 650 and the melting RF coil 350 will be described with reference to FIG.

The required amount of the metallic material M in the storage unit 60, which has been heated to a predetermined temperature by the heated inert gas G, is weighed by the weighing unit 70, sent to the buffer unit 80, and temporarily held. The metal material M held in the buffer section 80 is induction-heated by the preheating RF coil 650.
At this time, as long as the metal material M is not dissolved, the accumulating portion 60
Higher than that at, for example, 400
The metal material M is heated up to about ° C. Preferably, the metal material M is heated to the maximum temperature in the range below the solidus line. The temperature in the buffer unit 80 that can be higher than that in the storage unit 60 is that the metal material M is not required to be transported and weighed, and the metal material M can be appropriately charged from the buffer unit 80 toward the container 330. This is because the material M is enough. The metal material M supplied to the buffer unit 80 is
Since the temperature has been raised to the predetermined temperature, the buffer section 80 is quickly heated to the desired temperature. Buffer section 8
The period of preheating at 0 is, for example, while the molten metal material is being poured from the container 330 into the sleeve 360, so the time is limited. Therefore, if the temperature of the metal material M supplied to the buffer unit 80 is low, it may not be heated to a desired temperature in a limited time, but the storage unit 6
By heating the metal material M in such a range that it does not soften at 0, it is possible to heat it to a desired temperature in a limited time.

Metal material M measured from the buffer section 80
When the metal is supplied to the container 330, a current is supplied to the melting RF coil 350 to heat the metal material M, as shown in FIG.

When the melting of the metal material M in the container 330 is completed, the switching circuit 660 switches the supply of current to the preheating RF coil 650 in response to a control command from the control device 400. As a result, the metal material M held in the buffer section 80 is preheated.

When the pouring of the molten metal ML from the container 330 is completed, the supply of the electric current to the preheating RF coil 650 is cut off and the preheating operation of the metal material M is stopped. After that, the preheated metal material M is supplied from the buffer unit 80 to the container 330. Metal material M preheated from the buffer section 80
When the supply of is completed, the electric current is supplied to the melting RF coil 350 again.

As described above, according to this embodiment, by preheating the metal material M before supplying it to the container 330, the time required for melting the metal material M in the container 330 can be shortened. it can. Further, according to the present embodiment, the metal material M is preheated before being supplied to the container 330, so that the low temperature metal material is supplied to the container 330 that is formed of a material such as ceramics and has a high temperature, It is possible to prevent the occurrence of defects such as damage to 330 due to thermal shock. Further, according to the present embodiment, during the induction heating by the melting RF coil 350, the metal material M is measured in the measuring unit 70, the metal material M is sent to the buffer unit 80, and the molten metal ML of the container 330 is poured. The metal material M held in the buffer section 80 is preheated in hot water. Therefore, the operating rate of the induction heating power source 670 can be significantly improved.

Further, according to the present embodiment, the storage unit 60
By heating the metal material M in such a range that it does not soften, it is possible to reliably heat the metal material M to the desired temperature in the buffer section 80, and to shorten the time required for melting in the container 330.

In this embodiment, a single preheating RF is used.
Although the case where the coil 650 is provided in the buffer section 80 has been described, a plurality of preheating RF coils may be provided. In addition, the case where the temperature of the metal material M is raised by the heated inert gas G in the storage section 60 and the temperature of the metal material M after measurement is further raised by the preheating RF coil 650 in the buffer section 80 has been described. The invention is not limited to this. For example, the preheating RF coil 65
Even when 0 does not exist and preheating is not performed in the buffer section 80, the time required for melting in the container 330 is shortened by raising the temperature of the metal material M by the inert gas G heated in the accumulation section 60. Is possible.
Further, by preheating the metal material M in the storage unit 60, a low-temperature metal material is supplied to the container 330 that is formed of a material such as ceramics and has a high temperature, and the container 330 is damaged by thermal shock. Can be prevented.

Further, in the above-described embodiment, the case of a so-called cold chamber die casting machine has been described as the casting apparatus, but the present invention is not limited to this type of die casting machine, sand casting apparatus, gravity die casting apparatus, low pressure casting apparatus. Etc. are also applicable.

[0045]

EFFECTS OF THE INVENTION According to the present invention, when a required amount of metal material is supplied to each casting apparatus for continuous casting, oxidation of the metal material is prevented and preheating is performed to shorten the melting time. However, the casting cycle can be shortened.

[Brief description of drawings]

FIG. 1 is a sectional view showing a structure of a molten metal supply apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a current supply system that supplies a current to a preheating RF coil 650.

FIG. 3 is a diagram for explaining an example of a sequence of current supply to a preheating RF coil 650 and a melting RF coil 350.

[Explanation of symbols]

1. Molten metal supply device 60 ... Accumulator 70 ... Weighing unit 80: buffer section 90 ... Introduction 330 ... container 350 ... RF coil for melting 360 ... Sleeve 400 ... Control device 650 ... RF coil for preheating 851 ... Material supply unit 930 ... Gas heating device

Claims (6)

[Claims] 1. A molten metal supply apparatus for melting and supplying a metal material to a casting apparatus for each casting, for melting a metal material arranged at a predetermined position with respect to the casting apparatus. The container has a material supply means for supplying a metal material for each casting, and the material supply means has a storage part for storing the metal material, and an amount required for one casting from the storage part. A metering unit that sends out a metal material, a gas supply unit that supplies an inert gas to the storage unit to keep the metal material in an inert gas atmosphere, and an inert gas that is supplied to the storage unit by the gas supply unit. And a gas heating means for heating the gas in advance to a temperature in a range not melting the metal material accumulated in the accumulating section. 2. The material supply means holds a metallic material sent from the measuring section releasably until it can be supplied to the container, and a metallic material held by the temporary holding section. The molten metal supply apparatus according to claim 1, further comprising heating means for heating. 3. The metal material accumulated in the accumulating portion is weighed for each casting, and a required amount of the metal material is supplied to a container arranged at a predetermined position with respect to the casting apparatus. Is a molten metal supply method of heating and melting the metal material of to form a metal melt, and supplying the metal melt in the container to the casting apparatus, wherein an inert gas is supplied to the accumulating section, and the inert gas is supplied. A method for supplying molten metal, which comprises heating to a temperature in a range that does not melt the metal material accumulated in the accumulating unit. 4. The metal material supplied to the container is temporarily held in a temporary holding unit provided between the accumulating unit and the container each time the metal material is supplied to the container, and the metal material is stored in the container. The molten metal supply method according to claim 3, wherein the material is further heated by the temporary holding unit and supplied to the container until the material can be supplied. 5. A casting apparatus main body, and material supply means for supplying the metallic material to a container for melting the metallic material, which is arranged at a predetermined position with respect to the casting apparatus main body, for each casting. Then, the material supply means stores a storage part for storing the metal material, a metering part for sending out the metal material in an amount necessary for one casting from the storage part, and supplies an inert gas to the storage part. A gas supply means for placing the metal material in an inert gas atmosphere, and a range in which the metal material accumulated in the accumulation part is not melted by heating the inert gas supplied to the accumulation part by the gas supply means. And a gas heating means for preheating to the temperature of 1. 6. The material supply means holds a metallic material sent from the measuring section releasably until the metallic material can be supplied to the container, and a metallic material held by the temporary holding section. The casting apparatus according to claim 5, further comprising heating means for heating.