JP2003181624A - Apparatus and method for supplying molten metal as well as die casting machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for supplying a molten metal capable of melting and supplying a necessary mount of a metal material at each casting in the apparatus for continuously casting. <P>SOLUTION: The apparatus for supplying the molten metal comprises a container 330, a closed chamber 320 surrounding a periphery of the container, a melting coil 350 for melting the metal material M housed in the container 330 by induction heating to the molten metal, a sheathed thermocouple 920 as a temperature detecting means for detecting a temperature of the molten metal in the container 330, and a controller 400 for controlling supplying or shutting off of a current to the coil 350 and deciding a shutting-off time of the current to the coil 350 based on the temperature of the molten metal in the container 330, detected by the thermocouple 920 so that the temperature of the molten metal becomes a set temperature. <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 applied to a casting apparatus such as a die casting machine, a molten metal supply method, and a die casting machine equipped with this molten metal supply apparatus.

[0002]

2. Description of the Related Art A die casting machine is, for example, a pair of a fixed die and a movable die, a fixed die plate and a movable die plate which respectively hold the fixed die and the movable die, and a tie bar which is extended to form a fixed die. It is equipped with a mold clamping device for clamping the moving mold, an injection device for injecting molten metal into a cavity formed between the fixed mold and the moving mold, a hot water supply device for supplying molten metal to the injection device, and the like. There is. In such a die casting machine, while the fixed mold and the movable mold are clamped by the mold clamping device, the molten metal is supplied to the sleeve of the injection device by the hot water supply device, and the plunger fitted to the sleeve is driven. Thus, a die cast product is cast by injecting and filling molten metal into the mold cavity. The molten metal is supplied to the sleeve of the injection device by, for example, pumping a sufficient amount of metal material previously melted in a melting furnace using a ladle to pump the amount required for casting,
This is carried out by carrying this 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, a technique of melting a sufficient amount of a metal material required for one casting and supplying it to the sleeve instead of melting a sufficient amount of the metal material in the above-mentioned melting furnace is disclosed in Japanese Patent Publication No. 59-38867. It is disclosed in the publication. According to the technique disclosed in Japanese Patent Publication No. 59-38867, powdery or granular metal materials are supplied into a plurality of crucibles, which are melted by induction heating and conveyed to a hot water supply port of a die casting machine for injection. It is a thing. However, in the above technique, since the metal material is melted and conveyed in the atmosphere, the time in which the metal material is exposed to the atmosphere is long, the molten metal is easily solidified, and easily oxidized. Therefore, a film is formed on the surface of the molten metal, and this film remains in the crucible, so that the amount of the molten metal supplied to the die casting machine tends to vary.

The present invention has been made in view of the above problems, and an object thereof is a melting apparatus capable of melting and supplying a necessary amount of metal material for each casting in a casting apparatus for continuously casting. To provide a metal supply device. Another object of the present invention is to provide a die casting machine to which the above molten metal supply device is applied.

[0006]

A molten metal supply apparatus of the present invention is a molten metal supply apparatus for melting and supplying a metal material to a casting apparatus for each casting, and the molten metal supply apparatus is provided at a predetermined position with respect to the casting apparatus. A container arranged, a material supply means for supplying a metal material to the container for each casting, a heating means for heating and melting the metal material contained in the container to form a metal melt, and a metal melt in the container To supply the molten metal to the casting apparatus, temperature detecting means for detecting the temperature of the molten metal in the container, and a predetermined amount of electric current to the heating means, which is detected by the temperature detecting means. And a temperature control means for determining the timing of shutting off the current to the heating means based on the temperature of the molten metal in the container.

[0007] Preferably, the temperature control means is the temperature of the molten metal in the container detected by the temperature detection means, which is lower than a set temperature by a temperature determined based on the detection delay characteristic of the temperature detection means. When the low temperature is reached, the current to the heating means is cut off.

The temperature detecting means has a radiation thermometer for detecting the temperature of the molten metal based on the amount of infrared rays emitted from the molten metal in the container.

Preferably, the radiation thermometer further comprises gas supply means for supplying an inert gas into the closed chamber,
The detection surface is provided so as to face the introduction path of the inert gas.

The temperature detecting means may have a sheath thermocouple provided so as to be immersed in the molten metal in the container.

[0011] Preferably, the sheath further comprises a shield lid for opening and closing the opening of the container to prevent the metal material from scattering outside the container when the metal material contained in the container is heated. The thermocouple is installed on the shielding lid so that the shielding lid comes into contact with the molten metal in the container in a state where the opening of the container is closed.

The molten metal supply method of the present invention supplies a required amount of metal material to a container arranged at a predetermined position with respect to a casting apparatus for each casting, and heats the metal material supplied into the container. Is heated and melted to form a molten metal, the temperature of the molten metal in the container is detected by a temperature detecting means, and the detected temperature of the molten metal in the container is higher than a set temperature based on the detection delay characteristic of the temperature detecting means. When the temperature reaches a temperature lower by the temperature determined by the above, the electric current to the heating means is shut off, and the molten metal is flown out of the container and supplied to the casting apparatus.

The die casting machine of the present invention holds a pair of molds, opens and closes the molds, and clamps the molds, and a metal material melted in a cavity formed by the clamped molds. A die casting machine having an injection device for injecting and filling, and a molten metal supply device for injecting molten metal into the hot water supply port of the sleeve of the injection device,
The molten metal supply device includes a container arranged directly above the hot water supply port of the sleeve, a material supply means for supplying a metal material to the container for each casting, and a heating and melting of the metal material contained in the container. A heating means for converting the molten metal into a molten metal, a molten metal supply means for causing the molten metal in the container to flow toward the hot water supply port, a temperature detecting means for detecting the temperature of the molten metal in the container, and the heating means. Supply a certain amount of current,
The current to the heating means when the temperature of the molten metal in the container detected by the temperature detection means reaches a temperature lower than the set temperature by the temperature determined based on the detection delay characteristic of the temperature detection means. And a temperature control means for shutting off.

In the present invention, the metal material is supplied to the container by the material supply means for each casting, and then the metal melt is formed by induction heating. In this state, the drive shaft of the molten metal supply mechanism is rotated to tilt the container, and the molten metal is supplied to the casting apparatus through the inlet opened by the opening / closing means. In order to maintain a constant quality of the cast product, it is necessary to set the temperature of the molten metal supplied to the casting device to a preset temperature. That is, if the temperature of the molten metal supplied to the casting apparatus varies, the behavior of the molten metal also varies. Therefore, it is necessary to control the temperature of the molten metal. However, a large amount of energy must be applied to the metal material in a short time in order to continuously supply the metal material to the container for each casting, and the temperature of the metal material supplied to the container is short time. Since it changes drastically, it is difficult to detect the temperature of the molten metal and perform feedback control to make the temperature of the molten metal follow the set temperature. The present invention employs open loop control for melting and heating the metal material in the container by supplying a current to the induction heating means, and shuts off the current to the induction heating means based on the detected temperature of the molten metal. As a result, the molten metal in the container is controlled to the set temperature. Further, in the present invention, a radiation thermometer or a sheath thermocouple with a relatively small detection delay is used as the temperature detection means, and in addition, the supply and interruption of the current to the induction heating means are controlled in consideration of these detection delays. This enables more accurate temperature control.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a top view showing a configuration of a die casting machine according to an embodiment of the present invention. In FIG. 1, a die casting machine 1 includes a mold clamping device 100 and an injection device 200.
And a molten metal supply device 2. Mold clamping device 10
0 includes a fixed die plate 110, a movable die plate 120, and a link housing 130, which are respectively installed on the base frame BF. The fixed die plate 110 is fixed on the base frame BF,
The fixed die 101 is attached to the fixed die plate 110. On the back side of the fixed die plate 110, contact plates 111, 112 and 11 to be described later are provided.
3 is provided.

The movable die plate 120 is provided on the base frame BF so as to face the fixed die plate 110, and is movable in the mold opening / closing direction indicated by arrows A1 and A2. A moving die 102 that forms a cavity C with the fixed die 101 is attached to the moving die plate 120.

The link housing 130 is installed on the base frame BF.
0 is fixed die plate 1 by four tie bars 150
It is connected with 10. The tie bar 150 has an end portion on the fixed die plate 110 side fixed to the fixed die plate 110 and penetrates the movable die plate 120. Also,
A thread portion (not shown) is formed at an end portion of the tie bar 150 on the link housing 130 side, and a nut member (not shown) rotatably held by the link housing 130 is screwed into the thread portion. By rotating the four nut members in synchronization, the link housing 130 can move along the tie bar 150. On the back surface side of the link housing 130, the four nut members are rotated in synchronization, so that the link housing 13
A drive mechanism 131 for adjusting the position of 0 is provided.
The drive mechanism 131 drives a toggle mechanism 140 described later, in addition to adjusting the position of the link housing 130.

The toggle mechanism 14 having a first link 141 and a second link 142 is provided in the link housing 130.
0 is provided. Although not shown, the first link 141 and the second link 142 are provided in two sets up and down, the first link 141 is a linear link, and the second link 142 is an angled link.
One end of the first link 141 has a movable die plate 120.
Is rotatably connected to the second link 142 and the other end is rotatably connected to the second link 142. The second link 142 is rotatably connected to the first link 141, and is also rotatably connected to a link housing 130 and a moving member (not shown) movably provided in the mold opening / closing directions A1 and A2. A screw shaft (not shown) rotated by a servomotor included in the drive mechanism 131 is screwed into the moving member (not shown). The toggle mechanism 140 operates by directly moving a moving member (not shown) by the driving mechanism 131, and moves the moving die plate 120 in the mold opening / closing direction A1 or A2. In addition, the fixed mold 101 and the movable mold 102 are clamped in a state where the first link 141 and the second link 142 are completely extended linearly and self-locked.

The injection device 200 is a fixed mold 1 that is clamped.
The molten metal is injected and filled in the cavity C formed between 01 and the moving mold 102. Injection into cavity C,
A solid casting of the molten metal results in a die cast product. The injection device 200 includes a cylindrical sleeve 20 provided on the back side of the fixed die plate 110.
6, a plunger tip 205 fitted to the inner circumference of the sleeve 206, a plunger rod 204 having one end connected to the plunger tip 205, and a plunger rod 2
A cylinder device 201 that expands and contracts a piston rod 202 connected to the other end of the cylinder 04.

The sleeve 206 communicates with the cavity C. The sleeve 206 has a hot water supply port 206a, through which molten metal is supplied from a molten metal supply device 2 described later. The cylinder device 201 has a built-in piston, and a piston rod 202 and a plunger rod 2 connected to the piston.
04 and 04 are connected by a coupling 203.
The cylinder device 201 is hydraulically driven.

The plunger tip 205 is connected to the plunger rod 204, and moves inside the sleeve 206 when the cylinder device 201 is driven. The plunger tip 205 moves toward the fixed mold 101 side in the sleeve 206 to which the molten metal is supplied, so that the molten metal is injected and filled in the cavity C.

The molten metal supply device 2 melts the metal material supplied for each casting from the metering supply mechanism section 51 for supplying a required amount of metal material for each casting, and the melted metal. The melting mechanism unit 11 for injecting the material into the hot water supply port 206a of the sleeve 206 is provided. Dissolution mechanism 1
1 is an embodiment of the dissolving and supplying means of the present invention, and the metering and supplying mechanism section 51 is an embodiment of the metering and supplying means of the present invention. The melting mechanism unit 11 and the metering supply mechanism unit 51 are connected to each other, and these are provided on the movable plate 5.
Two guide rails 6 are installed on the upper surface of the movable plate 5. The guide rail 6 is the sleeve 2 described above.
It is arranged along the tube axis of 06. The molten metal supply device 2 is movable along the guide rail 6 in the directions of arrows C1 and C2.

The movable plate 5 is installed on the support base 3. On the frame of the support base 3, two guide rails 4 are installed along a direction orthogonal to the tube axis of the sleeve 206 described above. The movable plate 5 is movable along the guide rail 4 on the support base 3 in the directions of arrows B1 and B2. Therefore, the molten metal supply device 2 is movable in the directions of arrows C1 and C2 and the directions of arrows B1 and B2.

FIG. 2 shows the molten metal supply device 2 shown in FIG.
FIG. 7 is a diagram showing a state in which is moved to the back side of the fixed die plate 110. When casting is performed in the die casting machine 1, the molten metal supply device 2 is moved to the fixed die plate 110 from the fixed die plate 110 in a state where the melting mechanism portion 11 of the molten metal supply device 2 shown in FIG. Lock in place.

Specifically, the molten metal supply device 2 is connected to the arrow B.
1 to move the melting mechanism 11 to the contact plates 111, 11 provided on the back surface of the fixed die plate 110.
After reaching the position opposite to Nos. 2 and 113, the molten metal supply device 2 is moved in the direction of the arrow C2 to contact the contact plate 11.
Each side surface of the dissolution mechanism section 11 is pressed against 1, 112, 113.

The contact plate 112 is arranged in a direction orthogonal to the tube axis of the sleeve 206, and the contact plates 111 and 1 adjacent to the contact plate 112 are arranged.
13 are inclined at a predetermined angle with respect to the contact plate 112. Contact plates 111, 112, 11
By pressing the melting mechanism section 11 against 3, the positioning of the molten metal supply device 2 with respect to the fixed die plate 110 is performed.

Fixed die plate 1 of molten metal supply device 2
Fixing to 10 is performed by a pushing rod 30 shown in FIG. The length of the pushing rod 30 can be adjusted, and one end of the pushing rod 30 is pivotally connected to the frame of the molten metal supply device 2. The pushing rod 30 is oriented along the tube axis direction of the sleeve 206, and the other end of the pushing rod 30 is connected to the injection device 200.
The other end of the pushing rod 30 is pressed against the frame FL by facing the frame FL on the side and adjusting the length. As a result, the movement of the molten metal supply device 2 is restricted, and the molten metal supply device 2 is fixed to the back surface of the fixed die plate 110.

FIG. 3 is a view showing a concrete structure of the molten metal supply apparatus 2 described above, and is a view including a sectional view in a part of the molten metal supply apparatus 2 viewed from the back side of the fixed die plate 110. Is. As shown in FIG. 3, the base frame BF of the mold clamping device 100 includes a support base 50 installed on a base BS.
0, and the fixed die plate 110 is arranged at a predetermined height from the base BS.

On the other hand, the upper surface of the supporting table 3 on which the molten metal supplying device 2 is installed is located higher than the upper surface of the supporting table 500 of the base frame BF, and as described above, the guide rail 4 is attached to the supporting table 3. Is installed. The support base 3 has
The stairs 60 for ascending and descending the support table 3 in order to perform various operations on the molten metal supply apparatus 2 on the support table 3.
0 is set. A handrail 601 is provided on this staircase 600.
Is provided.

In FIG. 3, the molten metal supply device 2 is on the rear side of the fixed die plate 110 and is on the sleeve 206.
In addition to the above-mentioned dissolution mechanism section 11 arranged immediately above and the measurement supply mechanism section 51 connected to this dissolution mechanism section 11,
It has a capacitor housing section 300 installed below the metering and supplying mechanism section 51, and a control apparatus 400 installed below the support base 3 for performing various controls of the molten metal supply apparatus 2.

Metering and Supply Mechanism Section FIG. 4 is a cross-sectional view showing a specific structure of the metering and supply mechanism section 51. The metering and supplying mechanism section 51 includes a storage section 60, a metering section 70, a buffer section 80, and an introducing section 90.

The accumulating portion 60 accumulates the metal material before melting and supplying it to the sleeve 206. This storage unit 60 is
A hopper 61 and a lid 62 are provided. The hopper 61 is
It has a conical outer shape and has a space for housing 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 is attached to a support member 69c fixed to the upper surface of the case 300c of the capacitor housing portion 300.
Fixing members 69a, 6 for fixing the outer circumference of the lower end of the hopper 61
It is fixed by 9c.

The metal material M accumulated in the hopper 61 is, for example, a metal used for casting such as an aluminum alloy or a magnesium alloy in the form of elongated grains. The grain length is preferably about 2 to 7 mm, for example. The use of the granular metal material M makes it easier to accurately measure a relatively small amount of metal material, as compared with, for example, the case of cutting an ingot-shaped metal material. Also, when the metal material used for casting is granular, the surface of the material is always oxidized, so even if a granular metal material is used, if the grain length is made too short, the oxidized surface area will become large. However, if the grain length is made too large, accurate measurement becomes difficult.
Therefore, it is preferable to set the grain length in the above range.

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 to the outer periphery of the upper end of the hopper 61 to cover the opening of 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.

At a substantially central portion of the lid 62, a level detector 64 is provided.
And a gas introduction pipe 65. The level detector 64 is connected to the sensor amplifier 67, and detects the distance L between the level detector 64 and the upper surface of the metal material M housed in the hopper 61 in a non-contact manner, and outputs a detection signal to the sensor amplifier 67, for example. To 67. As the level detector 64, for example, a length measuring sensor using light, ultrasonic waves, or the like can be used. The sensor amplifier 67 is connected to the control device 400 described above, amplifies the detection signal of the level detector 64, calculates the distance L based on the amplified signal, and outputs this to the control device 400. Control device 400
Then, the remaining amount of the metal material M stored in the hopper 61 is determined based on the distance L. When the control device 400 determines that the inside of the hopper 61 is empty, it outputs an alarm, for example.

The gas introduction pipe 65 guides an inert gas G such as nitrogen gas or argon gas supplied from a gas supply source 66 provided outside the hopper 61 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 to the metering unit 70 and the buffer unit 80 through the supply port 61a at the bottom of the hopper 61.
And is introduced into the introduction unit 90.

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.
2 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 72 is a rotary shaft 7 having a circular cross section.
3 and a coil spring 74 fitted and fixed to the outer circumference of the rotary shaft 73. The rotating shaft 73 is
A tip portion projects from the cylinder 71, and the tip portion is rotatably supported by a bearing BR provided in the buffer portion 80. The rear end of the rotary shaft 73 is rotatably held by a bearing BR held by a support member 69c via a flange member 77, and is connected to a rotary shaft 76a of a servo motor 76 via a coupling. Has been done. The end of the cylinder 71 is sealed by the flange member 77 and the bearing BR held by the flange member 77.

The coil spring 74 is, for example, a wire material made of metal such as iron formed into a spiral shape at a substantially constant pitch, and has an inner diameter that fits into the outer diameter of the rotary shaft 73. . Both ends of this coil spring 74 are
For example, it is connected to the rotating shaft 73 by welding.

The reason why the screw 72 is constructed as described above is that the manufacturing cost can be greatly reduced as compared with the case where a screw is manufactured by cutting a bar material to form a spiral groove. Is.

The servo motor 76 is fixed to the support member 69c and is connected to the servo driver 79.
The servo driver 79 receives the control command 79s from the control device 400 and controls the rotation of the servo motor 76.

When the screw 72 is rotated in a predetermined direction, the metal material M supplied into the cylinder 71 is conveyed in the direction indicated by the arrow J in FIG. 4, and is sent to the buffer section 80 through the tip opening of the cylinder 71. This screw 7
The carry amount of 2 is determined according to the rotation amount of the screw 72.

Therefore, in the weighing unit 70, the control device 4
00 is a servo driver 79 for issuing a control command for instructing the rotation of the screw 72 that conveys the amount of the metal material M required for casting.
Measurement is performed by outputting to.

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 from the measuring unit 70 therein. The upper end side opening is closed by the closing member 85, and the lower end side opening 81a is inside. 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 is the control device 400 described above.
In response to the control command from, the supply of the compressed air supplied from the air source 87 to the air cylinder 82 is controlled, and the piston rod 83 is driven in the directions of arrows K1 and K2.

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 released from the buffer section 80 and falling by its own weight into the melting mechanism section 11. The introduction pipe 91 is connected to the lower end of the cylindrical member 81 by, for example, welding, and the connection between the lower end of the cylindrical member 81 and the introduction pipe 91 is sealed. Further, the introduction pipe 91 is arranged obliquely vertically downward and guides the metal material M falling from the buffer section 80 directly to a container in the melting mechanism section 11 described later.

As described above, the metering and feeding mechanism section 5
The transport path of the metal material M of the storage unit 60, the measuring unit 70, the buffer unit 80, and the introduction unit 90 of No. 1 is sealed from the outside, and the inert gas G is supplied from the storage unit 60 to allow the metal material M to pass through. Are measured and transported under an inert gas atmosphere.

Dissolving Mechanism Section FIG. 5 is a view of the dissolving mechanism section 11 seen from above, FIG. 6 is a sectional view taken along the line EE of the dissolving mechanism section 11 shown in FIG. 5, and FIG. 3 is a horizontal cross-sectional view of the melting mechanism section 11 shown in FIG. As shown in FIG. 5, the melting mechanism unit 11 includes a closed chamber 320 provided on the base plate 325.
The base plate 325 has a flange portion 325a connected to a predetermined portion of the capacitor housing portion 300 described above by a fastening means such as a bolt.

As shown in FIG. 6, the closed chamber 320 includes a base plate 325, a side plate 320a fixed to the base plate 325 by welding, and an upper plate 320b fixed to the upper end of the side plate 320a by welding. A substantially closed space 3 which is basically constructed and is surrounded by a base plate 325, side plates 320a and an upper plate 320b.
22. As shown in FIG. 6, the closed chamber 320 is provided with the sleeve 2 in a state in which it is arranged at a predetermined position on the back surface of the fixed die plate 110 of the die casting machine 1.
It is arranged directly above the hot water supply port 206a of 06.

The above-mentioned introduction pipe 91 is connected to the side plate 320a by welding, and the inside of the introduction pipe 91 and the closed space 322 of the closed chamber 320 communicate with each other. Introductory pipe 91
The connecting portion between the side plate 320a and the side plate 320a is sealed.

As shown in FIG. 6, in the closed chamber 320,
A container 330, a shielding lid 360, and a shutter member 370 are provided. A melting coil 350 is provided below the closed chamber 320. Furthermore, the closed chamber 32
A heating device 380 is installed on the upper plate 321 of No. 0.

The container 330 is arranged at a position capable of accommodating the metal material M guided by the introduction pipe 91 and falling into the closed chamber 320. The container 330 has an open upper end,
A cup-shaped accommodating portion 330a capable of accommodating the metal material M,
A pouring part 33 extending laterally continuously from the accommodating part 330a
It has 0b.

The container 330 is made of an electrically insulating and highly heat resistant material. Examples of the material for forming the container 330 include ceramics. Container 33
A coating material is applied to the inner peripheral surface of No. 0 to prevent the adherence of molten metal. Examples of the anti-adhesive agent include paints containing materials such as boron nitride, zinc oxide, magnesium oxide and the like. Since this paint peels off as the metal in the container 330 is repeatedly melted, it is necessary to apply the paint periodically.

The lower portion of the housing portion 330a of the container 330 passes through an opening 324 formed in the base plate 325,
It projects below the base plate 325.

The melting coil 350 surrounds the portion of the container 330 protruding below the base plate 325.
It is attached to the base plate 325. Melting coil 3
Reference numeral 50 is a pipe material 351 made of a copper alloy formed into a spiral shape. Cooling water CW is supplied to the inside of the pipe material 351. The periphery of the melting coil 350 is covered with an electric insulating member 353 such as ceramics. The electric insulating member 353 is formed into a truncated cone shape capable of sealing the opening 324 formed in the base plate 325 of the closed chamber 320. A cover 352 that covers and holds the periphery of the electrical insulating member 353 is fixed to the lower surface of the base plate 325 with bolts. By fixing the cover 352 to the lower surface of the base plate 325, the opening 324 of the base plate 325 is sealed by the electrically insulating member 353.

The melting coil 350 is, for example, several tens kHz when the metal material M contained in the container 330 is melted.
A high-frequency current of about a degree is supplied, and an induction current is induced in the metal material M. The Joule heat of this induced current heats and melts the metal material M. By supplying a high frequency current to the melting coil 350, the opening 32 of the base plate 325 is formed.
Induced current can be induced along the circumference of 4.
Therefore, a part of the periphery of the opening 324 of the base plate 325 is formed of an insulating material such as ceramics so as to block the induced current.

The container 330 is supported by a rotating shaft 392, and can be tilted in the direction of arrow K by rotating the rotating shaft 392 from the arrangement shown in FIG. The rotating shaft 392 is formed of a metal having high heat resistance such as stainless steel. On the other hand, the pouring part 3 of the container 330 of the base plate 325
The hot water supply port 2 of the sleeve 206 is provided on the lower side of the front end of 30b.
An opening 323 is formed so as to be located directly above 06a. The metal material M melted in the container 330 is poured into the sleeve 206 through the opening 323 and the hot water supply port 206a when the container 330 is tilted by the rotation of the rotating shaft 392.

As shown in FIG. 7, the container 330 and the rotating shaft 392 are connected via a support 390. A plurality of bolts are used to fasten the support 390 and the container 330. The supporting member 390 is the pouring unit 3 of the container 330.
The side of 30b is held, and the fitting member 391 is connected to the end of the support 390. The fitting member 391 is made of highly heat resistant metal such as stainless steel. A plurality of bolts are used to fasten the support 390 and the fitting member 391.

The fitting member 391 has, for example, a polygonal fitting hole such as a hexagon, and the rotary shaft 39 is provided in this fitting hole.
The second end portion 392a is fitted. The cross section of the tip portion 392a is a polygon that matches the fitting hole of the fitting member 391. The fitting member 391 is not fastened to the rotary shaft 392, and is removed by moving in the axial direction from the tip of the rotary shaft 392. That is, the container 330 can be removed from the rotation shaft 392 by moving it in the axial direction of the rotation shaft 392. The container 3 has such a configuration.
This is for facilitating the removal of the container 330 from the rotation shaft 392 when the above-mentioned paint is applied to 30 or when the container 330 is replaced due to damage or the like. Further, if the container 330 and the rotating shaft 392 are connected using a fastening member such as a bolt, the bolt may not be released due to the influence of heat.

Removing the container 330 from the rotary shaft 392,
An opening 326 is formed in the side plate 320a of the closed chamber 320 so as to be taken out of the closed chamber 320, as shown in FIG. A lid plate 320c for opening and closing the opening 326 is attached to the outside of the opening 326. The lid plate 320c is made of the same material as the side plate 320a. As shown in FIG. 8, the cover plate 320c has two elongated holes 320d formed at the upper end. These elongated holes 320d are locked to pins 320p provided so as to project from the surface of the side plate 320a of the closed chamber 320. That is, the lid plate 320c is not fastened to the side plate 320a. Therefore, at the time of maintenance, the lid plate 320c can be safely and easily removed even if the closed chamber 320 has a high temperature.

On the other hand, the outer surface of the cover plate 320c is pressed against the contact plate 113 of the fixed die plate 110 with the closed chamber 320 installed on the back surface of the fixed die plate 110. As a result, the cover plate 320c is opened 32
It is fixed at 6.

A seal member is provided on the surface of the cover plate 320c or around the opening 326 to seal the space between the cover plate 320c and the opening 326. Lid plate 320c
By providing the sealing member between the cover plate 320c and the periphery of the opening 326, when the cover plate 320c is pressed against the contact plate 113, the cover plate 320c and the opening 326 are sealed. As the sealing member, for example, a member having heat resistance such as glass fiber cloth is used.

Since the container 330 is not fixed in the axial direction of the rotating shaft 392, it is necessary to regulate the movement of the container 330 in the axial direction of the rotating shaft 392. Therefore, as shown in FIG. 7, a contact pin 399 is provided on the side plate 320a near the container 330 in a direction that is coaxial with the rotation shaft 392 and faces the rotation shaft 392. The contact pin 399 is removably inserted into a through hole formed in the side plate 320a, and the cover plate 3
By attaching 20c to the opening 326, the structure is immovable. Open the cover plate 320c with the opening 326.
The tip of the contact pin 399 is attached to the container 33.
By abutting 0, the axial movement of the rotation shaft 392 of the container 330 is restricted. The contact pin 399 can be pulled out by removing the cover plate 320c. After pulling out the contact pin 399, the container 330 is attached to the rotary shaft 39.
When pulled out in the axial direction of 2, the container 3 is opened through the opening 326.
The 30 can be taken out of the closed chamber 320.

As shown in FIG. 7, the rotary shaft 392 has a rear end portion projecting outside the sealed chamber 320, and the side plate 320.
It is rotatably supported by a slide bearing 393a held by a bearing holder 393 fixed to the outside of a.
The sliding bearing 393a is used, so that the sealed chamber 320 becomes extremely high in temperature due to heat due to melting of the metal material, heat of the heating device 380 to be described later, and the like, so that a bearing such as a ball bearing using a lubricant cannot be used. Because. Rotating shaft 392
Is connected to a servomotor 395 fixed to the outside of the closed chamber 320 via a gear train.

FIG. 9 shows a rotary shaft 392 and a servo motor 39.
FIG. 5 is a diagram showing a connection relationship with No. 5. As shown in FIG. 9, the rotary shaft 392 and the servo motor 395 are connected by a gear train 394 including a gear 394a connected to the shaft end of the rotary shaft 392 and a gear 394b connected to the output shaft 395a of the servo motor 395. Has been done. By the gear train 394, the rotation shaft 392 and the output shaft 395 of the servo motor 395
By connecting with a, heat conduction from the rotary shaft 392 to the servo motor 395 can be suppressed. That is, the contact area between the tooth flanks of the gear 394a and the gear 394b is sufficiently small, and the contact area between the rotary shaft 392 and the output shaft 395a is sufficiently smaller than that in the case where they are connected by a coupling.
Therefore, heat conduction from the rotary shaft 392 to the output shaft 395a can be suppressed, and damage to the servo motor 395 due to heat can be prevented. Further, in the transmission mechanism using a chain, a sprocket, and the like, a mechanical transmission error increases due to a temperature rise, but the gear train 394 hardly causes a transmission error even if the temperature rises. Therefore, the container 330 can be positioned at an accurate position. The gear 39
Ratio of the number of teeth Z2 of 4b and the number of teeth Z1 of the gear 394a Z2 /
Z1 is set to 1 or less.

The servo motor 395 is connected to the servo driver 396, as shown in FIG. The servo driver 396 is connected to the control device 400, and receives a control command from the control device 400 to control the rotation speed and the rotation position of the servo motor 395. That is, the control device 400 controls the inclination speed and the inclination posture of the container 330.

The heating device 380 heats the atmosphere in the closed chamber 320, the container 330 and the closed chamber 320 itself to promote the melting of the metal material M in the container 330 by induction heating, and the metal melted in the container 330. It is provided to suppress heat release from the material M and prevent solidification. The heating temperature of the heating device 380 is about the melting point of the metal material M or higher. As shown in FIG. 6, the heating device 380 is fixed to the upper plate 320b so as to cover the opening 321 formed in the upper plate 320b of the closed chamber 320. This heating device 380 includes a plate-shaped resistance heating element 382 held by a case 381, and the resistance heating element 382.
And the heating wire 383 embedded inside. The case 381 is fastened to the upper plate 320b of the closed chamber 320 with bolts.

The heating wire 383 is connected to the AC power source 386 via the connection terminal 385 as shown in FIG. The AC power supply 386 is connected to the control device 400 and supplies an alternating current to the heating wire 383 in response to a command from the control device. It is also possible to use a DC power supply instead of the AC power supply 386.

The resistance heating element 382 is arranged above the container 330, and the lower surface of the resistance heating element 382 is substantially parallel to the opening of the container 330. The resistance heating element 382 generates heat when electric current is supplied to the heating wire 383. When the resistance heating element 382 generates heat, the container 330, the closed chamber 32
The atmosphere in 0 and the closed chamber 320 itself are heated.

As shown in FIGS. 5 and 6, the heating device 3
At 80, a thermometer 375 and a gas supply pipe 376 are provided. The thermometer 375 is used for the housing portion 33 of the container 330.
0a and through the through hole 382h penetrating the resistance heating element 382, the temperature of the metal material M melted in the housing portion 330a of the container 330 is detected in a non-contact manner. A radiation thermometer is used as the thermometer 375. The radiation thermometer receives infrared rays emitted from the molten metal material M through the through holes 382h and detects the amount of the infrared rays. The thermometer 375, as shown in FIG.
The sensor amplifier 391 is connected to the thermometer 375.
The detected signal is amplified and the temperature of the metal material M is detected based on this signal. Further, the sensor amplifier 391 is connected to the control device 400, and the detected temperature is controlled by the control device 4.
Output to 00. The control device 400 controls, for example, the supply and interruption of the current to the melting coil 350 based on the input detected temperature. The specific temperature control by the control device 400 will be described later.

The gas supply pipe 376, as shown in FIG.
Through the inside of the resistance heating element 382, the above-mentioned thermometer 375
Is communicated with the through hole 382h. As shown in FIG. 5, a gas supply source 377 is connected to the gas supply pipe 376. The gas supply source 377 supplies, for example, an inert gas G such as argon gas or nitrogen gas. The inert gas G supplied from the gas supply source 377 is introduced into the sealed chamber 320 through the gas supply pipe 376. The inert gas G prevents the metal material M dissolved in the container 330 from being oxidized. Further, the inert gas G is supplied at a pressure higher than the atmospheric pressure in order to prevent the air from flowing into the closed chamber 320.

The structure in which the inert gas G is supplied into the closed chamber 320 through the through hole 382h for the thermometer 375 is such that the detection surface of the thermometer 375 faces the introduction path of the inert gas G. This is to prevent the metal melted in the container 320 from evaporating and adhering to the detection surface of the thermometer 375. That is, since the inert gas G is blown out from the through hole 382h toward the container 330 side, the evaporated metal cannot enter the through hole 382h.

As shown in FIG. 7, the shielding lid 360 is arranged in the vicinity of the container 330 and is fixed to the rotating shaft 361. The rotation of the rotating shaft 361 opens and closes the opening of the container 330. When a high frequency current is passed through the melting coil 350 while the granular metal material M is supplied to the container 330, an induced current flows through the metal material M. On the other hand, the melting coil 35
Due to the electromagnetic force generated between the magnetic field generated by 0 and the induced current flowing in the metal material M, the granular metal material M violently moves and tries to be ejected from the container 330. Therefore, when the metal material M is induction-heated in the container 330,
The container 330 is shielded by the shield lid 360, and the metal material M
Are prevented from squirting out of the container 330. The shield lid 36
Since a space is formed between the horizontal plate 360a of 0 and the housing portion 330a of the container 330, the granular metal material M can move in this space. Therefore, the shield lid 360
Has a shape projecting into the accommodating portion 330a so that the space between the horizontal plate 360a and the accommodating portion 330a is as narrow as possible and the movement of the metal material M in the container 330 is restricted as much as possible. It is also possible.

As shown in FIG. 6, the shielding lid 360 includes a horizontal plate 360a made of a flat plate member for covering the upper portion of the housing portion 330a of the container 330, and a horizontal plate 360a at one end of the horizontal plate 360a. And a vertical plate 360b made of a flat plate member for blocking the gap between the pouring part 330b and the containing part 330a. Shield lid 3
The horizontal plate 360a and the vertical plate 360b of 60 are made of a highly heat-resistant material such as ceramics.

The rotary shaft 361 that supports the shielding lid 360 is
As shown in FIG. 7, it is rotatably supported by a slide bearing 362a held by a bearing holder 362 fixed to the side plate 320a. The slide bearing 362a is used
This is because the hermetically sealed chamber 320 becomes extremely hot and thus a bearing such as a ball bearing using a lubricant cannot be used.
A gear 342 is connected to the end of the rotary shaft 361 that projects from the closed chamber 320. Gear 342
Engages with a gear 341 connected to the output shaft 340a of the rotary actuator 340 fixed to the base plate 325. As shown in FIG. 5, the rotary actuator 340 is connected to the pneumatic pressure source 337 via the control valve 336. The control valve 336 receives the control command from the control device 400 and controls the supply of air pressure from the air pressure source 337 to the rotary actuator 340. As a result, the rotary actuator 340 is rotationally controlled.

Shutter member 370 opens and closes opening 323 located directly above hot water supply port 206a of sleeve 206. That is, the shutter member 370 closes the opening 323 and prevents air from flowing into the sealed chamber 320 when the metal material M is melted in the container 330. The shutter member 370 is
When the metal material M melted in the container 330 is supplied to the hot water supply port 206a of the sleeve 206, the opening 323 is opened to secure the flow path of the metal material M.

As shown in FIG. 7, the shutter member 370 is supported by the tip of the connecting rod 371. The connecting rod 371 is attached to the base plate 3 by the slide bearing 387.
It is movably supported in a direction parallel to 25. The rear end of the connecting rod 371 is connected to the piston rod 372a of the air cylinder 372. Air cylinder 372
Is connected to an air source 374 via a control valve 373, as shown in FIG. The control valve 373 receives the control command from the control device 400 and receives the air source 37.
The supply of compressed air from No. 4 to the air cylinder 372 is controlled. As a result, the piston rod 372a of the air cylinder 372 expands and contracts.

When the piston rod 372a contracts, the shutter member 370 opens the opening 323, and when the piston rod 372a extends, the shutter member 37 extends.
0 closes the opening 323. When the shutter member 370 closes the opening 323, the shutter member 370 is provided with a pressing member 3 provided at a position facing the shutter member 370.
Abut 89. The shutter member 3 of the pressing member 389
The surface that abuts 70 is an inclined surface, and the inclined surface presses the shutter member 370 toward the opening 323 side. The shutter member 3 is pressed by the pressing member 389.
By pressing 70 toward the opening 323 side, the opening 323 is sufficiently sealed.

FIG. 10 is a diagram showing the connection relationship between the capacitor housed in the capacitor housing unit 300 and the melting coil 350. As shown in FIG. 10, the capacitor 302 is installed in the case 301 of the capacitor housing portion 300.

The capacitor 302 is a capacitor that is connected in parallel with the melting coil 350 to form a resonance circuit. This capacitor 302 is, for example,
The capacitor has a relatively large capacity of about 13 μF, and has a larger size than the melting coil 350.

The case 301 is installed under the metering and supplying mechanism section 51. In the metering and supplying mechanism section 51, the metal material M is supplied to the container 330 of the melting mechanism section 11 by dropping the metal material M by its own weight. For this reason, it is necessary to install the metering and supplying mechanism section 51 at a position higher than the melting mechanism section 11. As a result, a space is formed below the metering and supplying mechanism section 51. Capacitor 3 in this space
02 is installed, and the capacitor 302 is the melting coil 35.
It is adjacent to 0.

At the connection terminal 303 of the capacitor 302,
Two rigid copper plates 304 and 305 are connected to each other, and the copper plates 304 and 305 and the capacitor 302 are connected.
And are electrically connected to. Copper plates 304 and 305
Are arranged in parallel and extend from the case 301 to a position close to the melting coil 350. On the surfaces of the copper plates 304 and 305, a pipe material 351 made of copper or a copper alloy that constitutes the melting coil 350.
Is brazed. As a result, the melting coil 35
0 and the copper plates 304 and 305 are integrally connected. Further, the capacitors 302 and the melting coil 350 are electrically coupled by the copper plates 304 and 305.

Cooling water CW is supplied from a cooling water supply source 310 from one end of the pipe material 351 brazed to the copper plates 304 and 305, and this cooling water CW circulates through the pipe material 351 and flows out from the other end. . The cooling water CW is supplied to the pipe material 351 in order to prevent the pipe material 351 from being melted due to the temperature rise of the dissolution mechanism section 11.

FIG. 11 is a functional block diagram showing an example of the configuration of the supply system of the high frequency current to the melting coil 350. As shown in FIG. 11, the melting coil 350 is connected in parallel with the capacitor 302, so that the resonance circuit 3
Make up twelve. An inverter 314, a smoothing reactor 315, a rectifier circuit 316, and an AC power supply 317 are connected to the resonance circuit 312.

The AC power supply 317 supplies an AC current to the rectifier circuit 316. The rectifier circuit 316 rectifies the AC current supplied from the AC power supply 317, and smoothes the reactor 315.
Supply to. The smoothing reactor 315 has a rectifying circuit 316.
Smoothes the ripple contained in the DC current supplied from
It is supplied to the inverter 314.

The inverter 314 is a smooth reactor 31.
The current supplied from No. 5 is converted into an alternating current having a required frequency and supplied to the resonance circuit 312. In addition, the inverter 314
Is connected to the control device 400,
The operation is controlled in accordance with the control command from. The control device 400 uses, for example, the resonance circuit 3 based on the temperature of the molten metal in the container 330 detected by the thermometer 375.
Control the supply of alternating current to 12.

In the resonance circuit 312, in order to stably and efficiently dissolve the granular metal material M supplied to the container 330, the oscillated frequency is required to be as stable as possible. To be done. The frequency oscillated by the resonance circuit 312 is determined by the melting coil 350 and the capacitor 3
If the inductance between 0 and 02 fluctuates, it fluctuates sensitively. If the frequency oscillated by the resonance circuit 312 varies,
The penetration depth of the induced current induced in the metal material M into the metal material M fluctuates, the temperature of the metal material M does not rise stably, and the time required for melting the metal material M is increased for each casting. Vary. For example, when the melting coil 350 and the capacitor 302 are connected by a twisted pair cable, the melting coil 3 is deformed due to the deformation of the twisted pair cable.
The inductance between the capacitor 50 and the capacitor 302 easily fluctuates.

In this embodiment, the melting coil 350 and the capacitor 302 are brought close to each other, and the melting coil 350 and the capacitor 302 are connected by the copper plates 304 and 305, whereby the inductance between the melting coil 350 and the capacitor 302 is reduced. Of the resonance circuit 31
The frequency oscillated by 2 can be stabilized. When the melting coil 350 and the capacitor 302 are separated from each other, the melting coil 350 and the capacitor 302 are separated from each other by the copper plate 30.
In reality, it is difficult to connect them with 4, 305, but in the present embodiment, the melting coil 350 and the capacitor 3 are connected.
Since it has a structure that can minimize the distance to 02, it is possible to connect by the copper plates 304 and 305.

Forming Material of Dissolving Mechanism Section Here, the forming material of the constituent parts of the dissolving mechanism section 11 having the above-described configuration will be described. Container 3 of dissolution mechanism section 11
When a metal material is supplied to 30, melted by induction heating, and in addition, the inside of the closed chamber 320 is heated by the heating device 380, the temperature inside the closed chamber 320 is the heat from the melted metal or from the heating device 380. It becomes hot due to heat.
Further, during induction heating, magnetic flux may pass through the closed chamber 320, and the passage of magnetic flux may heat the closed chamber 320. Therefore, the closed chamber 3
The temperature of 20 becomes extremely high near the liquidus line of the metal material supplied to the container 330 or higher. For example, if aluminum or magnesium is used as the metal material, 600
℃ or more reaches up to 700 ℃.

Therefore, the base plate 325, the side plate 320a and the upper plate 320b forming the closed chamber 320 are made of a highly heat-resistant material having a melting point higher than that of the metal material M. Examples of these materials include S
Examples include austenitic stainless steel such as US304. The surfaces of the base plate 325, the side plate 320a, and the upper plate 320b are subjected to a surface treatment by hot dip aluminum plating and then subjected to a secondary diffusion treatment. Specifically, a plate material made of austenitic stainless steel is immersed in molten aluminum for a required time and taken out, and then the molten aluminum is solidified. afterwards,
For example, a secondary diffusion treatment is performed by burying an aluminum-plated plate material in powder containing aluminum as a main component and heating the plate material. Further, since austenitic stainless steel is not a ferromagnetic material, magnetic flux is less likely to concentrate during induction heating, and overheating due to induction heating is smaller than materials such as iron. By using the above-mentioned materials as the material forming the closed chamber 320, the heat resistance of the closed chamber 320 can be improved and the corrosion (oxidation, rust) resistance at high temperatures can be improved.

Rotating shaft 3 connected to the container 330 described above
92 is rotatably supported by a slide bearing 393a held by a bearing holder 393 fixed to the outside of the side plate 320a of the closed chamber 320. In addition, the shield lid 360
The rotary shaft 361 that supports the side plate 320 of the closed chamber 320 is
It is rotatably supported by a slide bearing 362a held by a bearing holder 362 fixed to a. Therefore, when the temperature of the closed chamber 320 becomes high, the sliding bearing 393a and the sliding bearing 362a also become extremely high, and if the material is made of a material having low heat resistance, the rotating shafts 392 and 361 may be burned. Therefore, the slide bearing 393a and the slide bearing 362a are made of ceramics such as aluminum oxide (alumina).

Further, as the temperature of the closed chamber 320 becomes high, the fastening members such as the various bolts used inside and outside the closed chamber 320 also become high in temperature, and the fastening members such as these bolts have poor heat resistance. If it is made of material, it may not be possible to release the fastening of the bolt. Therefore, the above-mentioned fastening member also has heat resistance and corrosion resistance at high temperatures, and in order to maintain the function of the fastening member even at high temperatures, a material that does not generate creep in a high temperature environment is used. As such a material, for example, a material defined in German Standard DIN 1.2888 or stainless steel is used. In addition, it is more preferable to use those that have been subjected to a surface treatment by hot-dip aluminum plating and then subjected to a secondary diffusion treatment.

Next, an example of the operation of the molten metal supply apparatus 2 having the above structure will be described with reference to FIGS.
The operation of the molten metal supply device 2 is controlled by the control device 400. First, the inert gas G is supplied from the gas introduction pipe 65 to the hopper 60 to which the granular metal material M has been supplied, and the metal material M is placed in the atmosphere of the inert gas G. Further, the inert gas G is supplied from the gas supply pipe 376 of the dissolution mechanism section 11 to make the inside of the sealed chamber 320 an atmosphere of the inert gas G. Further, an electric current is supplied to the heating device 380, and the container 3
30, the closed chamber 320, and the atmosphere in the closed chamber 320 are heated to about the melting point of the metal material M or higher.

From this state, the measuring unit 70 of the metering and supplying mechanism unit 51 is operated to measure the amount of the metal material M required for casting and send it to the buffer unit 80.

Next, after the metal material M weighed in the buffer section 80 is held, after the metal material M can be supplied to the container 330, the valve body 84 is lowered and the metal material M is dropped. Let After the drop of the metal material M is completed, the valve body 84 is raised to open the opening 81 of the buffer portion 80.
The introduction pipe 91 side of the closed chamber 320 is closed by closing a.

Metal material M dropped from the buffer section 80
Is guided to the introduction pipe 91 as shown in FIG.
It falls into the accommodating portion 330a of 30.

Then, after the supply of the metal material M to the container 330 is completed, as shown in FIG. 13, the shielding lid 360 is driven to shield the opening of the container 330. The container 33
After the supply of the metal material M to 0 is completed, the measurement for the next casting is started, and the new metal material M is sent to the buffer section 80 again.

After the opening of the container 330 is shielded by the shield lid 360, a high frequency current is supplied to the melting coil 350. The high frequency current supplied to the melting coil 350 is, for example, about 50 kHz.

When a high frequency current is supplied to the melting coil 350, an induced current is induced in the metal material M, and the metal material M
Is heated. At this time, as described above, the metallic material M violently moves due to the electromagnetic force and tries to be ejected from the container 330, but the metallic material M is not scattered from the container 330 by the shielding lid 360. If induction heating is continued in this state, as shown in FIG. 14, the metal material M is melted and becomes a metal melt ML.

Next, after a high-frequency current is supplied to the melting coil 350, when a predetermined time has passed, that is, when the metal material M is melted and is no longer scattered from the container 330, as shown in FIG. Open the lid 360. The reason why the shield lid 360 is opened is to detect the temperature of the molten metal ML.

After the shield lid 360 is opened, when the temperature of the molten metal ML in the container 330 is detected by the thermometer 375, the current supply to the melting coil 350 is controlled based on the detected temperature. . The details of the temperature control will be described later.

Next, when the temperature of the molten metal ML reaches a predetermined temperature, the electric current supply to the melting coil 350 is cut off, and then the shutter member 370 is moved to open the opening 323. After opening the opening 323, the container 330 is tilted as shown in FIG.

When tilting the container 330, the container 33
The tilt speed and tilt attitude of 0 are controlled. Container 3
The tilting speed and tilting attitude are controlled so that all the molten metal ML in 30 is poured into the sleeve 206 with certainty.
For example, when inclining the container 330, the container 330 is rotated at a relatively low speed so that the molten metal ML in the container 330 does not scatter, and after the container 330 is inclined to some extent, the container 330 is rotated at a relatively high speed. Then, the container 330 is again rotated at a relatively low speed before reaching the predetermined tilted posture as shown in FIG. The metal melt ML remaining in the container 330 is poured into the sleeve 206 by slowly rotating the container 330 at a relatively low speed before reaching the predetermined tilted posture.

When the molten metal ML is poured into the sleeve 206, the plunger tip 205 of the injection device 200 is driven to inject and fill the cavity C with the molten metal ML. When the container 330 reaches the predetermined tilted posture, the sleeve 20
After the injection of the molten metal ML into the container 6 is completed, the container 33
0 is returned to the normal posture. After returning the container 330 to the normal posture, when the metal material M can be supplied to the container 330, the metal material M is supplied again from the buffer unit 80 to the container 330, and the same operation as above is performed. I do.

Molten Metal Temperature Control Here, an example of temperature control of the molten metal ML in the container 330 by the control device 400 will be described with reference to FIG. When the high frequency current is supplied to the melting coil 350 after supplying the metal material M into the container 330, the temperature of the metal material M rapidly rises to become the metal melt ML,
The temperature of the metal material M further rises due to the continuous supply of the high frequency current. As described above, in order to melt the metal material M into the molten metal ML, it is necessary to supply a very large amount of energy in a short time. Therefore, the temperature detected by the thermometer 375 is fed back to the control device 400. It is difficult to supply the current for making the temperature of the molten metal ML follow the set temperature to the melting coil 350 on the basis of the deviation between the set temperature and the detected temperature, because it often exceeds the stability limit of the system system. is there. Therefore, in the present embodiment, as described above, the temperature control of the molten metal ML is basically an open loop control that is performed only by supplying and shutting off the current to the melting coil 350.

On the other hand, the radiation thermometer of the thermometer 375 is known as a thermometer having a relatively good response, but there is still a detection delay of several tens to several hundreds of msec. Therefore, for example, when the high-frequency current is supplied to the melting coil 350 after the metal material M is supplied into the container 330, the actual temperature RT of the molten metal ML and the detected temperature of the thermometer 375 as shown in FIG. An error occurs between DT and DT.
In FIG. 16, when the time when the temperature DT detected by the thermometer 375 reaches the set temperature ST of the molten metal ML is t ₂ ,
The actual temperature RT of the molten metal ML at the time point t ₂ is higher than the set temperature ST by ΔT. Therefore, at time t ₂ , if the supply of the high frequency current to the melting coil 350 is cut off, the metal melt ML of the set temperature ST cannot be supplied to the sleeve 206 of the die casting machine 1.

[0111] In this embodiment, as shown in FIG. 16, in advance considering that there is a detection delay in the detection characteristics of the thermometer 375, only the detection delay time tlag than time t ₂ before the time t ₁ The supply of the high frequency current to the melting coil 350 is cut off. The detected temperature DT of the thermometer 375 at this time point t ₁ is lower than the set temperature ST by Ta. That is, the temperature Ta is determined in advance based on the detection delay time tlag of the thermometer 375, and the temperature Ta is detected at the time t ₁ when the temperature DT detected by the thermometer 375 reaches a temperature Ta lower than the set temperature ST. The supply of the high frequency current to the coil for use 350 is cut off. By performing such temperature control, the molten metal ML supplied to the sleeve 206 of the die casting machine 1 is accurately controlled to the set temperature ST, and deterioration of product quality due to variations in molten metal temperature is less likely to occur. .

As described above, according to the present embodiment, in the die casting machine 1, the molten metal ML is supplied to the sleeve 206 by the above-described operation, so that die casting products are continuously cast in a constant cycle. be able to. Further, according to the present embodiment, since the granular metal material M is accurately measured in advance and melted, it is possible to supply the metal melt ML required for casting of the die cast product without excess or deficiency, and as a result, The quality can be improved. Further, according to the present embodiment, since the metal material is supplied and melted in the inert gas atmosphere, the metal material is less likely to be oxidized and the quality of the die cast product can be improved.

Further, according to the present embodiment, by enclosing the container 330 in the closed chamber 320 and heating the atmosphere in the closed chamber 320, the melting rate of the metal material can be improved, and it is possible to cope with a fast casting cycle. . Further, according to the present embodiment, the container 330 is surrounded by the closed chamber 320, and
By heating the atmosphere inside, solidification of the melted metal material can be prevented, and as a result, the quality of the product can be improved.

Further, according to the present embodiment, a current having a stable frequency can be stably supplied to the melting coil 350.
The metal material can be efficiently melted by induction heating, the time required for melting can be shortened, and the time required for melting can be suppressed from varying between castings.
Further, according to this embodiment, when the molten metal ML melted in the container 330 is poured into the sleeve 206, the container 3
Since the rotational speed control and the rotational position control of 30 are possible, the molten metal ML can be reliably poured into the sleeve 206. Further, since the rotational position of the container 330 can be accurately controlled, even if the volume of the closed chamber 320 is made as small as possible, the collision between the container 330 and the closed chamber 320 can be reliably prevented.

Furthermore, since the rotation position and rotation speed of the container 330 can be controlled accurately, it is also possible to adjust the amount of the molten metal ML to be poured from the container 330 into the sleeve 206. For example, by controlling the rotational position of the container 330 so that a part of the molten metal ML always remains in the container 330, it is possible to suppress the occurrence of violent motion of the granular metal material at the start of induction heating. You can

Further, according to the present embodiment, from the state where the melting mechanism section 11 of the molten metal supply device 2 is arranged on the back surface of the fixed die plate 110, the melting mechanism section 11 is moved to a position separated from the fixed die plate 110. It is movable. Therefore, it is possible to easily maintain the container 330 and the like in the closed chamber 320 of the dissolution mechanism section 11.

Second Embodiment FIG. 17 is a sectional view showing the structure of the melting mechanism section of the molten metal supply apparatus according to the second embodiment of the present invention. Note that, in FIG. 17, the same reference numerals are used for the same components as those of the melting mechanism unit 11 according to the above-described first embodiment. The components other than the melting mechanism section of the molten metal supply apparatus according to this embodiment are the same as those of the molten metal supply apparatus according to the first embodiment described above.

The melting mechanism 900 according to the present embodiment replaces the above-mentioned shield lid 360 with the upper plate 3 of the closed chamber 320.
A shield lid 910 that is opened and closed by a cylinder device 960 fixed on the 20b is provided. Cylinder device 96
0 is a connecting member 950 on the upper plate 320b of the closed chamber 320.
Is fixed through. The sealed chamber 320 is sealed by the connecting member 950. This cylinder device 960
Includes a piston rod 961 which expands and contracts in the vertical direction as indicated by arrows P1 and P2.
1 is driven in the sealed chamber 320 by, for example, compressed air.

The shield lid 910 is fixed to the tip of the piston rod 961 along the horizontal direction. The shielding lid 910 is provided on the container 3 according to the expansion and contraction of the piston rod 961.
The opening 330c of 30 is opened and closed.

A sheath thermocouple 920 is fixed to the lower surface of the shielding lid 910 along the vertical direction. The sheath thermocouple 920 is a thermocouple in which a thermocouple wire is inserted inside a metal protective tube (sheath) and hermetically filled with powder of an inorganic insulating material such as high-purity magnesium oxide. It has characteristics such as excellent insulation, airtightness, and responsiveness, and withstanding long-term use in a high temperature environment. The sheath thermocouple 920 has
From the viewpoint of detection responsiveness, those whose diameter is as small as possible,
For example, it is preferable to use one having a size of about 1 mm. The thermocouple wire 920a of the sheath thermocouple 920 is drawn out of the cylinder device 960 through the inside of the piston rod 961 and is connected to the above-described sensor amplifier 970. The sensor amplifier 970 amplifies the detection signal of the sheath thermocouple 920 and inputs it to the control device 400 described above. The control device 400 controls the molten metal temperature based on the input detected temperature as in the first embodiment described above.

FIG. 17 shows a state in which the metal material M is supplied to the container 330. From this state, as shown in FIG. 18, after the shielding lid 910 is processed toward the container 330 and the opening 330c of the container 330 is closed, and then the supply of the high frequency current to the melting coil 350 is started, The metal material M in 330 is melted and becomes the metal melt ML.
Since the sheath thermocouple 920 projects downward from the lower surface of the shielding lid 910, the tip of the sheath thermocouple 920 is in a state of being immersed in the molten metal ML.

Molten metal M detected by the sheath thermocouple 920
The detected temperature of L is input to the control device 400 through the sensor amplifier 970. In the same manner as described with reference to FIG. 16, the control device 400 considers the detection delay of the sheath thermocouple 920 and sets the detected temperature of the molten metal ML to the set temperature ST.
When the temperature reaches a temperature lower by a temperature corresponding to the detection delay of the sheath thermocouple 920 than that, the supply of the high frequency current to the melting coil 350 is cut off.

After the supply of the high frequency current to the melting coil 350 is cut off, the shield lid 910 is raised to a position where it does not interfere with the container 330, and the molten metal ML in the container 330 is poured into the sleeve 206 of the die casting machine 1. .

As described above, according to the present embodiment, with the above configuration, it is possible to bring the sheath thermocouple 920 into direct contact with the molten metal ML and detect the temperature of the molten metal ML. The molten metal ML controlled to the set temperature can be stably supplied to the sleeve 206 of the die casting machine 1.

Third Embodiment FIG. 19 is a sectional view of a melting mechanism portion of a molten metal supply apparatus according to still another embodiment of the present invention. The molten metal supply apparatus according to the present embodiment has the same configuration as that of the above-described first embodiment except the configuration of the melting mechanism section. Further, in FIG. 19, the same reference numerals are used for the same components as those of the melting mechanism section 11 according to the first embodiment.

The melting mechanism 511 shown in FIG.
20 and the melting coil 3 arranged around the container 520
50 and an opening / closing mechanism 550.

The container 520 is made of a cylindrical member having an accommodation space 520a capable of accommodating the metal material M therein. This container 520 has an opening 520d at the bottom, and this opening 520d is arranged above the hot water supply opening 206a of the sleeve 206. Around the hot water supply port 206a of the sleeve 206, a hopper 525 for preventing the molten metal from scattering.
Is provided.

The introducing pipe 91 of the material supply mechanism 51 described in the first embodiment is connected to the upper end of the container 520. The metal material M is supplied into the container 520 through the introduction pipe 91.

The opening / closing mechanism 550 has a lid 551 that opens and closes the bottom of the container 520, and an actuator 552 that drives the lid 551. The lid 551 is disposed so as to face the opening 520d of the container 520, so that the opening 520d
It is composed of a plate-like member capable of closing d. Actuator 55
2 is constituted by, for example, a cylinder device, and the opening 520d of the container 520 is opened / closed by the lid 551 by expanding / contracting the piston rod 552a whose tip is connected to the lid 551.

Like the first embodiment, the melting coil 350 is electrically coupled to the capacitor 302 by the copper plates 304 and 305 arranged in parallel.

In the melting mechanism section 511 having the above structure, first,
The metal material M is supplied through the introduction pipe 91 into the container 520 in which the opening 520d is closed by the lid 551. After that, a high frequency current is supplied to the melting coil 350 to melt the metal material M in the container 520. When the metal material M is melted to form the metal melt ML, the lid 551 is driven and the opening 520d of the container 520 is opened. As a result, the molten metal ML in the container 520 falls by its own weight and is supplied into the sleeve 206 through the hot water inlet 206a.

In each of the above-described embodiments, the case of a so-called cold chamber die casting machine was described as the casting apparatus, but the present invention is not limited to this, but other types of die casting machines, sand casting machines, gravity die casting machines, and low pressure casting machines are used. It is also applicable to devices and the like.

[0133]

According to the present invention, a required amount of metal material can be melted and supplied for each casting to a casting apparatus for continuously casting. Further, according to the present invention, the melting time of the metal material can be shortened, and it becomes possible to suppress the deterioration of the quality of the cast product due to the solidification and the oxidation of the melted metal material before being supplied to the casting apparatus.

[Brief description of drawings]

FIG. 1 is a top view showing a configuration of a die casting machine according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state where the molten metal supply device 2 shown in FIG. 1 is moved to the back side of a fixed die plate 100.

3 is a diagram showing a specific configuration of the molten metal supply device 2, and is a diagram including a sectional view in a part of the molten metal supply device 2 viewed from the back side of the fixed die plate 110. FIG.

FIG. 4 is a sectional view showing a specific configuration of a material supply mechanism section 51.

FIG. 5 is a view of the melting mechanism section 11 seen from above.

6 is a cross-sectional view of the melting mechanism section 11 shown in FIG. 5 taken along the line EE.

7 is a horizontal cross-sectional view of the melting mechanism section 11 shown in FIG.

FIG. 8 is a diagram showing a structure of a cover plate 320c for opening and closing an opening 326.

9 is a diagram showing a connection relationship between a rotary shaft 392 and a servo motor 395. FIG.

10 is a diagram showing a connection relationship between a capacitor housed in a capacitor housing unit 300 and a melting coil 350. FIG.

FIG. 11 is a functional block diagram showing an example of a configuration of a supply system of a high frequency current to a melting coil 350.

FIG. 12 is a diagram for explaining an operation procedure of the molten metal supply device 2.

FIG. 13 is a view for explaining the operation procedure of the molten metal supply device 2 following FIG.

FIG. 14 is a view for explaining an operation procedure of the molten metal supply device 2 following FIG. 13.

FIG. 15 is a view for explaining the operation procedure of the molten metal supply device 2 following FIG.

16 is a graph for explaining an example of temperature control of the molten metal in the container 330 by the control device 400. FIG.

FIG. 17 is a sectional view showing a configuration of a melting mechanism section of a molten metal supply apparatus according to a second embodiment of the present invention.

18 is a diagram showing a state in which the temperature of the molten metal is being detected in the melting mechanism section shown in FIG.

FIG. 19 is a cross-sectional view of a melting mechanism section according to still another embodiment of the present invention.

[Explanation of symbols]

1 ... Die casting machine 2 ... Molten metal supply device 11,511 ... Dissolution mechanism part 51 ... Material Supply Department 60 ... Storage unit 70 ... Weighing unit 80 ... buffer section 90 ... Introduction 91 ... Introduction tube 100 ... Mold clamping device 110 ... Fixed die plate 120 ... Moving die plate 130 ... Link housing 300 ... Capacitor housing 320 ... Closed chamber 330 ... container 350 ... Coil for melting 360 ... Shielding lid 370 ... Shutter member 375 ... Thermometer 520 ... Container 550 ... Opening and closing mechanism 551 ... Lid 552 ... Actuator 900 ... Dissolution mechanism section 910 ... Shielding lid 920 ... Sheath thermocouple 920a ... Thermocouple wire 960 ... Cylinder device 961 ... Piston rod 970 ... Sensor amplifier

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // B22D 41/06 B22D 41/06

Claims (10)

[Claims] 1. A molten metal supply device for melting and supplying a metal material to a casting device for each casting, and a container arranged at a predetermined position with respect to the casting device, and a metal for each casting in the container. A material supply means for supplying a material, a heating means for heating and melting a metal material contained in the container to form a metal melt, and a metal melt supply means for causing the metal melt in the container to flow toward the casting device. A temperature detecting means for detecting the temperature of the molten metal in the container, controlling the supply and interruption of electric current to the heating means, and the temperature of the molten metal in the container detected by the temperature detecting means. A molten metal supply device having a temperature control means for determining the timing of shutting off the current to the heating means so that the temperature of the molten metal becomes a set temperature based on the above. 2. The temperature control means, the temperature of the molten metal in the container detected by the temperature detection means is lower than a set temperature by a temperature determined by the detection delay characteristic of the temperature detection means. 2. The molten metal supply apparatus according to claim 1, wherein the electric current to the heating means is cut off when the temperature reaches the temperature. 3. The molten metal supply according to claim 1, wherein the temperature detecting means has a radiation thermometer that detects the temperature of the molten metal based on the amount of infrared rays emitted from the molten metal in the container. apparatus. 4. A gas supply means for supplying an inert gas into the sealed chamber, wherein the radiation thermometer is provided so that a detection surface faces the introduction path of the inert gas. 3. The molten metal supply device according to item 3. 5. The molten metal supply apparatus according to claim 1, wherein the temperature detecting means has a sheath thermocouple which is provided so as to be dipped in the molten metal in the container. 6. The sheath thermocouple further comprising a shield lid for opening and closing the opening of the container to prevent the metallic material from scattering outside the container when the metallic material contained in the container is heated. 6. The molten metal supply apparatus according to claim 5, wherein the shielding lid is installed on the shielding lid so as to come into contact with the molten metal in the container in a state where the shielding lid closes the opening of the container. 7. A required amount of metal material is supplied for each casting to a container arranged at a predetermined position with respect to a casting apparatus, and the metal material supplied into the container is heated and melted by a heating means to melt the metal. The temperature of the molten metal in the container is detected by the temperature detecting means, and the detected temperature of the molten metal in the container is lower than the set temperature by the temperature determined by the detection delay characteristic of the temperature detecting means. A molten metal supply method in which when a low temperature is reached, the current to the heating means is shut off, and the molten metal is allowed to flow out of the container and supplied to the casting apparatus. 8. The method for supplying molten metal according to claim 7, wherein a radiation thermometer is used as the temperature detecting means, and the temperature of the molten metal is detected based on the amount of infrared rays emitted from the molten metal in the container. 9. A sheath thermocouple is used as the temperature detecting means,
The molten metal supply method according to claim 7, wherein the sheath thermocouple is immersed in the molten metal in the container to detect the temperature of the molten metal. 10. A mold clamping device that holds a pair of molds and opens and closes and molds the molds, and injects and fills a molten metal material into a cavity formed by the molds that have been clamped. A die casting machine having an injection device and a molten metal supply device for injecting molten metal into the hot water supply port of the sleeve of the injection device, wherein the molten metal supply device is arranged directly above the hot water supply port of the sleeve. A container, a material supply means for supplying a metal material to the container for each casting, a heating means for heating and melting the metal material contained in the container to form a metal melt, and a metal melt in the container for supplying the metal A molten metal supply means for flowing out toward the mouth, a temperature detecting means for detecting the temperature of the molten metal in the container, and a predetermined amount of current supplied to the heating means, and the container for detecting the temperature detecting means. Money Die casting machine having a temperature control means for interrupting the current to the heating means when the temperature reaches the temperature amount corresponding low temperature determined based on the detection delay characteristic of the temperature detection means than the set temperature of the molten metal.