JPH05285625A - Injection molding device for metallic formed body - Google Patents

Abstract

PURPOSE:To carry out a series of molding processes in which a semi-solidified slurry is manufactured from an ingot to be injection molded in one device. CONSTITUTION:A material supplying chamber 3 connected to an injector at its end side is vertically divided by a first shutter 35 and a second shutter 36 into an ingot introducing chamber 31, a heating chamber 32 and a heat retaining chamber 33 and a chopping chamber 34 is provided below the heat retaining chamber 33. The ingot is heated in the heating chamber 32 to be semi-solidified state and the ingot W is chopped by a chopper 58 in the chopping chamber 34. While the above processes are carried out, the inside of each chamber is in an inert atmospheric state by a vacuum pump 62 and an inert gas bomb 63 to prevent the oxidation of materials of Mg alloy and the like. A screw 7 is provided below the chopping chamber 34 to make a semi-solidified slurry and to inject it into a metallic mold.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an injection molding machine for a metal molded body, in which a series of molding processes from the production of a semi-solidified slurry to the injection molding are carried out in one apparatus.

[0002]

2. Description of the Related Art Conventionally, there has been known a device in which an ingot-shaped metal material is crushed by a crusher, a semi-solidified slurry is formed, and this is injected into a mold by an injection machine. For example, Japanese Patent Application Laid-Open No. 3-258452 disclosed by the present applicant
No. was proposed as such a device, and in this device, after supplying an ingot-shaped metal material to a supply chamber, argon gas was circulated in the chamber to maintain an inert atmosphere and a semi-molten state at a predetermined temperature. The ingot in the semi-molten state is then crushed by a crusher and fed into the heating cylinder of the injection machine, and at the same time the semi-solidified slurry is formed by the rotating stirring action of the screw in this cylinder to form the mold. I'm trying to eject. The material supply chamber is made to have an inert atmosphere in order to prevent contamination with impurities by avoiding contact with air when the metal material to be handled is a metal that is easily oxidized, such as an aluminum alloy or a magnesium alloy. is there. Then, each of these steps is continuously performed in one device to eliminate the need for incidental equipment, prevent impurities from being mixed into the metal material, and improve the durability of the screw of the injection machine.

[0003]

However, in the case of the above apparatus, since the heating and holding of the ingot-shaped metal material and the crushing by the crusher are processed in a single chamber, the next shot is performed when the material is crushed. There was a problem that the material could not be supplied and heated and the productivity could not be improved. That is, as described above, it is necessary to maintain the inert atmosphere state of the material supply chamber in order to avoid mixing of impurities due to oxidation, and the chamber cannot be opened while the material being crushed remains. is there.

[0004]

In order to solve such a problem, the present invention divides a material supply chamber connected to one end side of an injection machine into at least two chambers by a partition member, and an ingot is provided upstream of a material supply path. A heating chamber for heating and holding the metal material in the shape of a ring is provided, and a crushing chamber for crushing the metal material in the shape of an ingot is provided on the downstream side. The partition member is openable / closable in a direction orthogonal to the metal material supply path.

[0005]

By dividing the material supply chamber into two or more chambers, even if the work for supplying the next shot ingot to the heating chamber and heating and holding the same while the ingot is being crushed in the crushing chamber is not performed in the crushing chamber. The active atmosphere state can be maintained. Therefore, cycleability is enhanced. By opening and closing the partition member in the direction orthogonal to the supply path, it can also serve as a stopper for the ingot. Moreover, when the supply path is vertical, for example, the ingot can smoothly fall freely into the crushing chamber. Can be done.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an injection molding device for metal molded articles of the present invention will be described with reference to the accompanying drawings. FIG. 1 is an enlarged view of a material supply chamber, which is a main part of the present invention, and FIG. 2 is an overall view of an injection molding apparatus.

First, the general outline of the injection molding apparatus will be described with reference to FIG.

The injection molding machine of the present invention comprises a mold 2 connected to one end side of the injection machine 1 and a material supply chamber 3 connected to the other end side of the injection machine 1, and an ingot supplied from the material supply chamber 3 The metal material W in the shape of a circle is processed to form a semi-solidified slurry, which is then injected into the mold 2.

The injection machine 1 has a heating cylinder 6 supported by a cylinder holder 5 on a support 4, a kneading screw 7 provided in the heating cylinder 6, and a plunger machine connected to the tip of the heating cylinder 6. A plunger tip 12 is slidably provided in a ceramic sleeve 11 of a plunger sleeve 10 of the plunger machine 8.

The periphery of the plunger sleeve 12 is covered with a heat-retaining heater 13, and a heat insulating material 14 is further provided around it.
Is provided. In addition, a plurality of thermocouples for temperature control are provided at predetermined locations on the plunger sleeve 12.

On the other hand, a resistance heating coil 16 and a heat insulating material 17 are also provided around the heating cylinder 6, and an attachment 19 surrounded by a ceramic attachment 18 is provided on the tip side so that the slurry has a tapered tip. The supply port 20 is formed. The slurry supply port 20 opens toward the inner peripheral surface of the ceramic sleeve 11. The heating cylinder 6 is also provided with a plurality of temperature adjusting thermocouples.

The kneading screw 7 has a stop valve 2 at the tip.
3, the stop valve 23 has a diameter larger than the minimum tip end diameter portion of the slurry supply port 20 so that the slurry supply port 20 can be closed when moving forward, and the rear end portion side is provided with a screw. It is connected to a rotation motor 24 and is rotatable. The screw rotation motor 24 is mounted on the support base 4 via a slide guide 25 and is slidable forward and backward (left and right in the drawing).

The spiral groove of the kneading screw 7 is provided at least in front of the material supply chamber 3, and the material supply chamber 3 communicates with the upper part of the rear end of the spiral groove.

By the way, the rear end side of the kneading screw 7 extends further rearward from the screw rotation motor 24 through a coupling and is connected to a screw forward / backward movement cylinder unit 26. Therefore, the operation of the cylinder unit 26 for screw forward / backward movement causes the kneading screw 7 to move.
And the screw rotation motor 24 moves back and forth.

On the rear end side of the heating cylinder 6, a sealing portion 27 is formed by combining a sliding portion with the kneading screw 7 with a rotary sliding seal and a dust seal as shown in FIG.
In addition, a metal packing and a metal seal are used at predetermined locations to prevent contact with the outside.

A ceramic plate 28 is provided at the joint between the support base 4 and the cylinder holder 5, a cooling coil 29 is provided on the support base 4 side, and a cooling coil is also provided on the rear end side of the heating cylinder 6. 29 is provided for cooling. This is because the cylinder holder 5 is heated more than a normal injection molding machine, so that adverse effects on other devices and the like are avoided.

Now, regarding the structure of the material supply chamber 3,
It will be described with reference to FIG.

The material supply chamber 3 is divided from above into an ingot introduction chamber 31, a heating chamber 32, a greenhouse chamber 33, and a chop chamber 34, and a space between the introduction chamber 31 and the heating chamber 32 is a first shutter 35 as a partition member. And the second shutter 36 is provided between the heating chamber 32 and the greenhouse 33.
It is said that it can be blocked by.

That is, the first and second shutters 35,
The open / close cylinder unit 37 can be moved back and forth horizontally by the open / close cylinder units 37 and 38, and is opened / closed in the direction orthogonal to the material supply path formed in the vertical direction.

The introduction chamber 31 is provided with an ingot insertion hatch 41 on the upper part of the casing 40, and the inside of the chamber is kept at a predetermined temperature by a resistance heater 42 surrounding the casing 40. And this resistance heater 4
The periphery of 2 is covered with a heat insulating material 43.

In addition, the ingot insertion hatch 41 includes:
An open / close cylinder unit 44 for opening / closing vertically is connected, and a slide shaft 45 slidable up / down with respect to the insertion hatch 41 is provided.

At the lower end of the slide shaft 45,
An ingot holder 46 that supports the lower portion of the ingot W is provided to be connected to the lower end of a rotary shaft 47 that further penetrates the center of the slide shaft 45, and a holding frame 49 is provided to the middle portion of the slide shaft 45. The rotary knob 48 provided on the upper end of the rotary shaft 47 rotates the rotary shaft 47 and the ingot holder 46. The ingot holder 46 is used to transfer the ingot W onto the second shutter by lowering the ingot W into the heating chamber 32 and rotating the lower surface of the ingot W to a position where the lower surface of the ingot W comes off as described later. Is.

Also, the insertion hatch 41 and the casing 40.
And the sliding joints between the first and second shutters 35 and 36 and the casing 40, the rotary joints, etc., are all sealed by a metal packing or a metal seal for sealing. Same as each room.

Next, the heating chamber 32 is a chamber for heating the ingot W, and is provided with a ceramic sleeve 51 around which an induction heating coil 50 is wound.

Then, the ceramic sleeve 51 is
The induction heating coil 50 is, for example, a ceramic such as silicon nitride, alumina, sialon, zirconia, or the like, and the induction heating coil 50 is a copper pipe extending from the coil outlet 52 of the casing 40 to the outside. I am trying to introduce.

The second shutter 36 slides along the lower end of the ceramic sleeve 51, and is made of ceramic in consideration of the influence of induction heating.
Further, the shaft 53 coupled to the shutter 36 is also connected to the rod of the opening / closing cylinder unit 38 via the joint 54 as a ceramic shaft.

The greenhouse 33 is a chamber for preventing the temperature from decreasing until the heated ingot W is chopped, and the chamber height is longer than the other two chambers, and a temporary stock chamber for materials, Alternatively, it is considered to also serve as a supply amount adjusting chamber.

The material is normally supplied by free fall from above, but in order to make the fall smooth, the upper side of the casing 40 has a funnel shape, and a resistance heater 55 is wound around the casing 40 in the narrowed lower portion. Has been. And the circumference is covered with the heat insulating material 56.

The chop chamber 34 is a chamber for cutting and crushing the ingot W having a reduced deformation resistance and supplying the ingot W to the kneading screw 7 below. 58 is provided.

The biaxial chopper 58 has a pair of rotating bodies having mutually opposite spiral blades, and the rotating bodies are rotated in opposite directions so that the spiral blades are meshed in a non-contact state and the ingot W is moved downward. It is crushed so as to be drawn into. The biaxial chopper 58 rotates in synchronization with the kneading screw 7, and when stopped, the ingot W
Also serves as a stopper.

The chop chamber 34 is also heated and kept warm by the resistance heater 59 in order to avoid a temperature drop.
In some cases, the rotation axis of the chopper 58 is doubled,
A rod-shaped heater may be placed inside, and a ceramic bearing may be used as the bearing at this time.

Further, the chopper 58 is driven by a hydraulic pressure or an electric motor, but its installation position is far away from the device in order to avoid heat damage, and a heat insulating material is used in the middle of the power transmission system.

By the way, the introduction chamber 31 and the heating chamber 32
An inert atmosphere mechanism 61 is connected to.

The inert atmosphere mechanism 61 is used in the introduction chamber 3
1. a vacuum pump 62 for sucking air from the heating chamber 32,
Gas cylinder 63 for filling the same chamber 31, 32 with an inert gas
And a pipe line 66 that communicates with the introduction chamber 31 and the heating chamber 32 via the three-way valve 64, the leak valve 65a, and the other valve 65b, and the like. It is designed to be filled with an inert gas.

As the inert gas, for example, argon, nitrogen, carbon dioxide or the like is used.

The operation of the above injection molding apparatus will be described.

First, when the injection molding machine is ready, the vacuum pump 62 is actuated to evacuate the greenhouse chamber 33, the chop chamber 34, the heating cylinder 6 chamber, and the like through the introduction chamber 31 and the heating chamber 32. An inert gas is supplied from the gas cylinder 63 to make the inside of the apparatus an inert atmosphere.

After that, the first shutter 35 that has been open until then is closed, the introduction chamber 31 is opened to the atmosphere through the leak valve 65a, and the opening / closing cylinder unit 44 lifts the ingot insertion hatch 41 and the ingot holder 46.

Subsequently, when the ingot W of, for example, magnesium alloy is set in the ingot holder 46 by a manual work or an automatic carrier, the open / close cylinder unit 44 is opened.
Is lowered and the insertion hatch 41 is closed again. Then, the leak valve 65a is also closed.

Then, the introduction chamber 31 is driven by the vacuum pump 62.
The inside pressure is reduced, but at this time, the inside of the introduction chamber 31 is heated within the range of 100 ° C. to 300 ° C. by the heater 42, and the water adhering to the surface of the ingot W is evaporated and discharged together with the air.

After that, the first shutter 35 is opened while maintaining the depressurized state as it is or by introducing an inert gas into an inert atmosphere.

Here, the slide shaft 45 descends, and the ingot W on the ingot holder 46 is inserted into the ceramic sleeve 51 of the heating chamber 32. When the insertion is completed, the rotary knob 48 rotates the rotary shaft 47 and the ingot holder 46 to release the lower surface support of the ingot W. Therefore, the ingot W is transferred onto the second shutter 36.

After that, the ingot holder 46 is raised, the first shutter 35 is closed, and heating of the ingot W is started. At the same time as this heating, the procedure for introducing the next shot of ingot W can be performed in the introducing chamber 31.

The ingot W is heated under the conditions set in advance by a test, for example, until the ingot W reaches the semi-solidified region with a predetermined power, frequency and time.

At this temperature, the solid fraction of the ingot W is in the range of about 50% to 90%, while the shape of the ingot W is maintained and the chopper 58 does not require an excessive force during chopping. It is preferable to be able to heat to, and in the case of general magnesium alloy (AZ91),
About 564 ° C to 493 ° C is suitable.

The final temperature control of the semi-solidified slurry is
Since it is performed in the heating cylinder 6 of the injection machine, the temperature control width in the heating chamber 32 may be any that can be heated to, for example, a solid phase ratio of 50% or less, and the process control is easy.

When the heating is completed, the second shutter 36 is opened and the ingot W falls into the greenhouse 33 below. Then, as described above, when the two-axis chopper 58 is not operating, the ingot W stands by on the chopper 58, but this chamber is heated at the same temperature as the heating chamber 32, and during standby or during chopping. This prevents the temperature of the ingot W from decreasing.

The second shutter 36 is then closed,
In the heating chamber 32, the next ingot W can be inserted and heated.

When the chopper 58 of the chop chamber 34 operates, the ingot W is finely divided. That is, the heated ingot W has a deformation resistance reduced from about several hundredths to several thousandths, and is torn and crushed and cut by the spiral blades of two counter-rotating rotating bodies. It

Then, the cut metal material is supplied to the kneading screw 7, and the solid dendrite is divided and granulated by the strong stirring action of the screw 7 and the heating from the heating cylinder 6 to form a semi-solidified slurry in the front. Be carried to.

The slurry carried forward enters the inside of the plunger sleeve 10, the screw 7 advances when a predetermined amount is accumulated, the stop valve 23 closes the slurry supply port 20, and the plunger machine 8 injects.

While the ingot is crushed in the chop chamber 34 by the above apparatus, the heating chamber 32
In order to prevent oxidation by heating the next shot ingot and blocking it from the outside during that time, this apparatus can also perform in-line MMC molding, which has been frequently manufactured in recent years.

That is, such MMC (metal matrix composite material)
There is a method such as compocasting in which ceramic particles or the like are placed in a semi-solidified slurry and dispersed while stirring, but a ceramic powder supply port is provided in a screw 7 part or the like directly below the chop chamber 34. This is because the MMC slurry can be easily manufactured in the heating cylinder 6.

Further, MMC in which ceramic particles and the like are dispersed
It is also possible to use an ingot. At this time, MM
C ingots are difficult to machine and the processing cost is extremely high if they are processed into pellets, but if they are in a semi-solid state, the deformation resistance will be sufficiently smaller than at room temperature, and heating and feeding will be done like alloy ingots. Therefore, molding can be performed without increasing the cost.

[0055]

As described above, according to the present invention, since the material supply chamber is divided into at least two chambers so that the ingot can be heated and crushed at the same time, the productivity is extremely high. Further, during this period, by completely shutting off from the outside, impurities such as oxidation are not mixed, and high quality molded products can be manufactured. Further, by opening and closing the partition member so as to be orthogonal to the supply path, when the supply path is formed vertically, for example,
The partition member can serve as a stopper, and the transportation due to its own weight can be smoothly performed.

[Brief description of drawings]

FIG. 1 is an enlarged view of a material supply chamber, which is a main part of the present invention.

[Figure 2] Overall view of the injection molding machine

[Explanation of symbols]

 1 Injection Machine 2 Mold 3 Material Supply Room 31 Introductory Room 32 Heating Room 33 Greenhouse Room 34 Chop Room 35 First Shutter 36 Second Shutter 61 Inert Atmosphere Mechanism W Ingot

Claims (3)

[Claims] 1. An ingot-shaped metal material is supplied from a material supply chamber connected to one end side of the injection machine, and this metal material is made into a semi-solidified slurry and injected into a mold communicating with the other end side of the injection machine. In the injection molding apparatus for a metal formed body, the material supply chamber is divided into at least two chambers by a partition member, and a heating chamber for heating and holding the ingot-shaped metal material is provided on the upstream side of the supply path while the downstream side is provided. An injection molding apparatus for a metal molded body, wherein a crushing chamber for crushing the ingot-shaped metal material is provided in the. 2. The injection molding device for a metal molded body according to claim 1, wherein the partition member is openable and closable in a direction orthogonal to the supply path of the metal material. 3. The injection molding apparatus for a metal molded body according to claim 1, wherein the ingot-shaped metal material is a magnesium alloy or an aluminum alloy, and the heating chamber is in an inert atmosphere.