JP2002248557A - Semi-solidified casting method and machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semi-solidified casting method and machine wherein a specific amount of part taken from semi-solidified metal is supplied into a molding machine. SOLUTION: Semi-solidified metal M kept in a semi-solidifying unit 1 is charged from a discharging port 131a into the weighing hole 21 of a receiving member 20. The charged semi-solidified metal is cut from the remainder by the receiving member 20 itself and the specific amount of the semi-solidified metal m is weighed. Then the semi-solidified metal m is supplied into the molding machine 3. The rotational move of the receiving member 20 repeats the charging stage where the semi-solidified metal M is charged by making the weighing hole 21 communicate with the discharging port 131a, the cutting stage where the communication of the weighing hole 21 with the discharging port 131a is finished and the specific amount of the semi-solidified metal is cut from the remainder by the opening end 21 a of the weighing hole 21, and the discharging stage where the semi-solidified metal m in the weighing hole 21 is discharged. It is preferable to design the discharging port 131a to be blocked by the outer circumferential surface 20a when the weighing hole 21 does not communicate with the discharging port 131a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semi-solid casting method for casting a molten metal in a semi-solid state, and a semi-solid casting apparatus for performing the casting method.

[0002]

2. Description of the Related Art In a semi-solid casting method in which a metal in a semi-solid state (hereinafter, also referred to as a "semi-solid metal") is supplied to a mold and cast, a molten metal (molten metal) is supplied to the mold. Compared with the method, the temperature of the material at the time of supply is low, and since the part of the material is solidified and dispersed uniformly, the latent heat of solidification is small, so the heat load on the mold is small and the whole is uniform There is an advantage that a perfect product (molded product) can be obtained.

In the above-mentioned semi-solid casting method, a predetermined amount of semi-solid metal corresponding to the volume of a molding die or the like is supplied to a molding device (a sleeve of a die casting device or the like). At this time, in order to accurately control the supply amount to the molding device, prepare a semi-solid metal larger than the amount used for one casting,
From this, it is desirable that the above-mentioned predetermined amount of semi-solid metal is weighed, fractionated from the remaining semi-solid metal, and supplied to the forming apparatus. In the case where semi-solid casting is performed a plurality of times continuously, a large amount of semi-solid metal (for example, an amount corresponding to several to ten castings) is prepared to some extent, and the semi-solid metal bath is removed from the semi-solid metal bath. By fractionating a certain amount of semi-solid metal and supplying it to the molding device, effects such as improvement of manufacturing efficiency and reduction of quality variation can be expected. In the following, the metal material divided for each predetermined amount used for one casting is also referred to as “billet”.

[0004]

However, since the state of the semi-solid metal changes greatly depending on the temperature change, it is difficult to divide a predetermined amount by a simple means such as scooping out like a conventional molten metal. difficult. The semi-solid metal has a higher viscosity than the molten metal, and furthermore, it is difficult to handle, for example, it is in a jelly state in a stationary state and cannot be dropped by its own weight from a sorting container or the like. Therefore, a method of once solidifying a semi-solid metal prepared from a molten metal, cutting the solidified metal into a billet, and reheating the billet to a semi-molten state and supplying the billet to a molding apparatus is often used. ing. However, this method requires energy for reheating the billet and equipment for the same.

On the other hand, JP-A-7-32113 discloses that
Once the semi-solid metal (Reometal) prepared by the Leomaker is transferred to a preheated heat-insulating container,
A die casting method of rheometal which transfers the container to a molding apparatus and then tilts the container to supply it to the molding apparatus is disclosed. However, in the embodiment described in the above publication, the “slide valve” provided at the lower part of the rheometer to control the discharge amount of the rheometal causes the remaining leometal transferred into the heat-insulating container to remain (the rheometal in the leomaker). ). Therefore, a mechanism for controlling the amount of discharged rheometal by time, weight, and the like, and controlling the slide valve according to the amount of discharged metal is required, and the apparatus becomes complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a semi-solid casting method and a semi-solid casting apparatus, in which a predetermined amount of semi-solid metal is fractionated from a semi-solid metal and supplied to a forming apparatus.

[0007]

According to a first aspect of the present invention, there is provided a semi-solid casting method comprising the steps of: discharging a part of a semi-solid metal held in a semi-solid apparatus into an outlet of the semi-solid apparatus; From the filling into the weighing hole of the receiving member, then, by moving the receiving member, the semi-solid metal in the weighing hole is cut from the rest by the receiving member itself and a predetermined amount of the semi-solid metal is weighed,
Thereafter, the semi-solid metal in the weighing hole is supplied to a forming device.

According to a second aspect of the present invention, there is provided a semi-solid casting method according to the first aspect, wherein the receiving member is a rotating body having the weighing hole opened in an outer peripheral surface thereof. A filling step of connecting the weighing hole and the discharge port to fill the weighing hole with semi-solid metal, and terminating the communication between the weighing hole and the discharge port and opening an end of the weighing hole in the weighing hole. The cutting step of cutting the semi-solid metal from the rest and the discharging step of discharging the semi-solid metal in the weighing hole and supplying it to the molding device are repeatedly performed, and the weighing hole and the discharge port are communicated. When not present, the discharge port is closed by the outer peripheral surface.

The semi-solid casting apparatus according to claim 3 is
A semi-solidification device that holds a metal in a semi-solid state, and a portion of the semi-solid metal in the semi-solidification device is filled into a weighing hole of a receiving member, and then the semi-solidified metal in the weighing hole is moved by moving the receiving member. The receiving member itself cuts the remaining portion and weighs a predetermined amount of the semi-solid metal, then forms a weighing device for discharging the semi-solid metal in the weighing hole, and forms the semi-solid metal discharged from the weighing device. And a molding device that performs the molding.

According to a fourth aspect of the present invention, in the semi-solid casting apparatus according to the third aspect, the receiving member has an outer peripheral surface capable of closing an outlet of the semi-solid apparatus, and the outer peripheral surface has the weighing device. It is a rotating body having an opening.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The semi-solidification apparatus can prepare (hold) a semi-solid metal in an amount larger than an amount used for at least one casting. The semi-solid metal may be prepared directly from the molten metal, or may be a solid prepared from the molten semi-solid metal and then re-melted.
From the viewpoint of energy efficiency, it is preferable to use a semi-solid metal prepared directly from the molten metal. The semi-solid metal may be prepared by mixing two or more metals in a semi-solid state so that a solid phase appears instantaneously.

The semi-solidification apparatus preferably includes a heating means such as a high-frequency heating element and an electric heater in order to adjust the temperature of the metal to a predetermined solid-liquid coexisting temperature range to obtain an appropriate semi-solid state. Further, the semi-solidification device is an electromagnetic stirrer,
It is preferable to provide a stirring means such as a mechanical stirrer using a stirring propeller. By performing the adjustment of the semi-solid metal under agitation, the semi-solid structure can be homogenized, and the semi-solid metal having a fine and / or spherical dendrite structure can be adjusted. Further, it is preferable that the semi-solidification device includes a pressurizing unit for performing the preparation of the semi-solidified metal under pressure. By adjusting the semi-solid metal under pressure, shrinkage cavities due to solidification shrinkage of the metal can be prevented, and healthy (without defects such as voids) semi-solid metal can be reliably adjusted, and the predetermined amount can be adjusted. It is possible to accurately sort and supply a sound semi-solid metal to the forming apparatus.

The number of weighing holes provided in the receiving member may be one, or may be two or more. When the receiving member has two or more weighing holes, it is preferable that these weighing holes are provided at equal intervals (for example, at a constant rotation angle if the weighing holes are opened on the outer periphery of the rotating body). . This receiving member is preferably formed of a heat insulating material such as ceramics in order to suppress a temperature change of the semi-solid metal collected in the weighing hole. Further, a temperature adjusting means such as a high-frequency heating element may be provided around the weighing hole. An air vent communicating with the bottom of the weighing hole may be provided inside the receiving member or on the wall surface of the weighing hole. Thus, the back pressure at the time of discharging the semi-solid metal in the weighing hole is reduced, so that the discharge of the semi-solid metal (supply to the molding device) can be performed easily and reliably. Further, when filling the weighing hole with the semi-solid metal, the air in the weighing hole can be released to the outside, so that the filling property of the semi-solid metal into the weighing hole is improved.

The "movement" of the receiving member may be a movement for transporting the entire receiving member in a specific direction, for example, or a movement for rotating the receiving member about an axis (rotational movement). In the present invention, it is preferable that a rotating body such as a disk or a column is used as the receiving member, and the opening of the weighing hole is moved with respect to the discharge port by rotating the rotating body. The semi-solid metal filled in the weighing hole is cut from the remaining semi-solid metal by the “receiving member itself” by the movement of the receiving member. Therefore, it is not necessary to drive a separate member (such as a slide valve) for this cutting, so that the apparatus configuration and its control are easy. In addition,
In order to enhance the cutting ability of the semi-solid metal by the receiving member, a cutting blade may be provided at the open end of the weighing hole.

[0015]

The present invention will be described below in detail with reference to examples. First Embodiment (1) Outline of Apparatus A semi-solid casting apparatus according to a first embodiment is shown in FIG. The semi-solid casting apparatus prepares a semi-solid metal from a molten metal, and a semi-solid apparatus 1 for holding the semi-solid metal M, and a semi-solid metal m of a quantity used for one casting. And a forming device 3 for forming the semi-solid metal m discharged from the weighing device 2.

The semi-solidifying apparatus 1 includes a molten metal crucible 11, a molten metal supply path 12 connected to the molten metal crucible 11, and a semi-solidified metal to which a required amount of molten metal is supplied from the molten metal crucible 11 through the molten metal supply path 12 as needed. And a holding unit 13. The semi-solid metal holding part 13 is a cylindrical body 131 connected to the molten metal supply path 12.
And a high-frequency heater (heating means) 13 provided inside the wall surface of the cylinder 131 to adjust the temperature of the metal in the cylinder 131
2 and an electromagnetic stirrer (stirring means) 133 installed on the outer periphery of the cylinder 131 to stir the metal in the cylinder 131.
The lower portion 131a of the cylinder 131 functions as an outlet for supplying the semi-solid metal M in the cylinder 131 to the weighing device 2.

The weighing device 2 includes a receiving member 20 formed of a heat insulating material such as ceramics. This receiving member 20 is a disk-shaped rotating body, and its outer peripheral surface 20
A cylindrical weighing hole 21 opening at a is provided. The capacity of the weighing hole 21 is smaller than the amount of the semi-solid metal M held in the cylindrical body 131. The receiving member 20 is rotatably supported below the outlet 131 a of the semi-solidification device 1. As shown in FIG. 3, the mounting position of the receiving member 20 is such that the outer peripheral surface 20 a
1a functions as a bottom lid for sealing (however, as shown in FIG. 1, the discharge port 131a of the semi-solidification device 1 and the weighing hole 21).
Except when they are contacted).

The molding device 3 includes an injection sleeve 31 to which the semi-solid metal m in the weighing hole 21 is supplied from the weighing device 2.
And a plunger 32 for injecting the semi-solid metal m in the injection sleeve 31 and a molding die 33 for molding the injected semi-solid metal m into a predetermined shape. The supply port 311 of the injection sleeve 31 is located immediately below the receiving member 20.

(2) Operation of Apparatus The procedure for performing semi-solid casting using this semi-solid casting apparatus will be described. As shown in FIG. 3, the molten metal in the molten metal crucible 11 is supplied into the cylindrical body 131 through the molten metal supply path 12, where it is cooled to a predetermined solid-liquid coexisting temperature range, and is kept warm by the high-frequency heating body 132. You. At this time, by stirring the metal in the cylinder 131 with the electromagnetic stirrer 133, it is possible to obtain the semi-solid metal M having a finer and more spherical dendrite structure. At this stage, the receiving member 20 is in the rotational position where the weighing hole 21 and the discharge port 131a are not connected, and the discharge port 131a
Is closed by the outer peripheral surface 20a.

By rotating the receiving member 20 in the direction of arrow A, as shown in FIG.
1a, the semi-solid metal M is discharged from the outlet 131a.
From its own weight and fills the weighing holes 21 (filling stage). Next, when the receiving member 20 is further rotated,
As shown in FIG. 2, the connection between the weighing hole 21 and the discharge port 131a is cut off. At this time, the semi-solid metal m filled in the weighing hole 21 is removed from the remaining portion (in the cylindrical body 131) by using the momentum of rotation of the receiving member 20 between the opening end 21a of the weighing hole 21 and the discharge port 131a. From the remaining semi-solid metal M) (cutting stage). As a result, a predetermined amount of semi-solid metal m corresponding to the volume of the weighing hole 21 is weighed, and
It is collected in one. Further, the discharge port 131a is connected to the outer peripheral surface 20.
It is closed again by a.

When the receiving member 20 is further rotated, as shown in FIG. 3, when the opening of the weighing hole 21 comes directly above the supply port 311 of the injection sleeve 31, as shown in FIG.
Is dropped by its own weight, is discharged from the weighing hole 21, and is supplied to the injection sleeve 31 (discharge stage). Then, the semi-solid metal m in the injection sleeve 31 is filled into the mold 33 by the plunger 32 and molded to obtain a semi-solid cast part as a product. On the other hand, after the connection between the weighing hole 21 and the discharge port 131a is cut off, the molten metal is replenished from the molten metal crucible 11 to the cylindrical body 131, and the weighing hole 21 and the discharge port 131a are next connected by the rotation of the receiving member 20. In the meantime, the semi-solid metal for the next casting is adjusted from the remaining semi-solid metal M and the newly supplied metal M ′, and held in the cylinder 131. Thereafter, by repeating this procedure continuously, a predetermined amount of semi-solid billet can be supplied to the molding apparatus 3 and a semi-solid cast part can be manufactured from this semi-solid billet. The receiving member 20 is preferably used after preheated to the same temperature as the semi-solid metal M.

(Second Embodiment) FIG. 4 shows a semi-solid casting apparatus according to a second embodiment. Note that the same reference numerals are used for components having substantially the same structure as in the first embodiment described above, and redundant description is omitted. The semi-solidification device 1 includes a pressurizing piston (pressurizing means) 14 slidable in the cylindrical body 131 and configured to pressurize the metal supplied from the melt crucible 11 to the cylindrical body 131. The pressurizing piston 14 also has a function of shutting off the molten metal supply path 12 and the cylindrical body 131 during the pressurization. By causing the metal supplied into the cylindrical body 131 to be in a semi-solid state while being pressurized by the pressurizing piston 14, it is possible to prevent the occurrence of a "shrinkage cavity" due to the coagulation and contraction of the metal. Therefore, a more solid semi-solid metal M (containing no defects such as vacancies) can be adjusted as compared with the case where the pressurization is not performed. Also, by discharging the semi-solid metal M from the discharge port 131a under the pressure of the pressurizing piston 14, the semi-solid metal M can be surely reached to every corner of the weighing hole 21.
Can be filled. As described above, by using the semi-solidification device 1 including the pressurizing unit, the quantity (capacity) of the semi-solid metal m collected by the weighing device 2 can be made more accurate.

Further, the receiving member 20 is
And a piston 23 whose one end is in contact with the outer periphery 22a of the cam 22 and moves up and down in the weighing hole 21 according to the rotational position of the receiving member 20.
And a movable bottom cover 24 attached to the other end of the piston 23
And built-in. In this embodiment, the cam 22 is attached so that the piston 23 is at the top dead center position when the opening of the weighing hole 21 comes to the right. At this top dead center position, as shown in FIG. 5, the semi-solid metal m in the weighing hole 21 is extruded to the outside by the movable bottom cover 24 and supplied to an injection sleeve (not shown) of the molding device 3. According to this mechanism, as in the first embodiment, the semi-solid metal m is placed in the weighing hole 2.
Unlike the method in which the semi-solid metal m in the weighing hole 21 can be mechanically discharged at an arbitrary angle unlike the method of dropping from the weight 1 to the injection sleeve 31 and supplying it to the injection sleeve 31, the installation position of the molding device 3 can be freely set. It has the advantage of increasing the degree.

In the above embodiment, no means is provided for actively adjusting the temperature of the semi-solid metal m in the weighing hole 21. For example, as shown in FIG.
A heating means such as a high-frequency heating body 71 may be provided in a portion located inside the weighing hole 21 inside the weighing hole 21. Thereby, until the semi-solid metal m cut from the semi-solid device 1 is supplied to the forming device 3, a change in the state (temperature, solid phase ratio, etc.) of the semi-solid metal m can be suppressed. .

In the above embodiment, the weighing hole 21 has a simple cylindrical hole shape. For example, as shown in FIG. 7, the weighing hole 21 has a groove 811 extending in the axial direction on the outer periphery of the cylindrical shape, and the lower end of the groove 811 has Notch 812 leading to inside of cylinder
As shown in FIG. 8, the air vent 8 communicating with the bottom is formed by using a nested structure in which the inner cylinder 81 is fitted into a cylindrical hole provided in the receiving member 20 as shown in FIG.
It may be a weighing hole 82 provided with 11a. By providing the air vent 811a, when the semi-solid metal m is discharged from the weighing hole 82, the back pressure of the semi-solid metal m is reduced, so that the viscous semi-solid metal m is easily discharged. The semi-solid metal M is weighed from the semi-solid apparatus 1 into the weighing holes 82.
When filling the air vent, air in the weighing hole 82 is
Since the semi-solid metal M can be reliably filled to the corners of the weighing hole 82, the weighing accuracy of the semi-solid metal m is improved.

[0026]

According to the semi-solid casting method and apparatus of the present invention, a semi-solid metal used in one casting is fractionated from the semi-solid metal prepared (held) in the semi-solid apparatus. The semi-solidified billet is supplied to a molding device. Since the process of cutting the semi-solid metal filled in the weighing hole from the remaining portion (the semi-solid metal remaining on the semi-solidification device side) is performed by the receiving member itself, the operation of the slide valve described in the above publication is separately performed. There is no need for control, and there is no risk of malfunction such as sticking of the slide valve. Further, the amount (volume) of the semi-solid metal separated from the semi-solid metal in the semi-solid apparatus can be controlled by the capacity of a weighing hole provided in the receiving member. Thus, a mechanism for managing the amount of discharged semi-solid metal from the semi-solidified apparatus by time, weight, and the like, and a mechanism for controlling the amount of discharged metal can be omitted, so that the apparatus configuration and its control are simple.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a filling stage in a semi-solid casting apparatus according to a first embodiment.

FIG. 2 is a schematic sectional view showing a cutting stage in the semi-solid casting apparatus of the first embodiment.

FIG. 3 is a schematic sectional view showing a discharge stage in the semi-solid casting apparatus of the first embodiment.

FIG. 4 is a schematic sectional view showing a filling stage in the semi-solid casting apparatus of the second embodiment.

FIG. 5 is a schematic sectional view showing a discharging stage in the semi-solid casting apparatus according to the second embodiment.

FIG. 6 is a schematic sectional view showing a receiving member provided with a temperature adjusting device.

FIG. 7 is a perspective view showing an inner cylinder used for forming a weighing hole provided with an air vent.

8 is a sectional view taken along line VIII-VIII in FIG.

[Explanation of symbols]

Reference Signs List 1; semi-solidifying device, 11; molten metal crucible, 13; semi-solid metal holding portion, 131; cylinder, 131a; outlet, 132; high-frequency heating body (heating means), 133; electromagnetic stirrer (stirring means), 14; Pressurizing piston (pressurizing means), 2; weighing device, 20; receiving member, 20a; outer peripheral surface, 21;
21a; open end, 3; molding device, 31; injection sleeve,
311; Supply port, 33; Mold, M; Semi-solid metal in semi-solid apparatus, m; Sorted semi-solid metal.

Claims (4)

[Claims] 1. A part of semi-solid metal held in a semi-solidifier is filled into a weighing hole of a receiving member from an outlet of the semi-solidifier, and then the half of the weighing hole in the weighing hole is moved by moving the receiving member. A semi-solid casting method characterized in that the solidified metal is cut from the remainder by the receiving member itself, a predetermined amount of the semi-solid metal is weighed, and then the semi-solid metal in the weighing hole is supplied to a molding device. 2. The receiving member is a rotating body having the weighing hole opened in an outer peripheral surface thereof, and the weighing hole is connected to the discharge port by rotation of the receiving member, so that the weighing hole is semi-solidified. A filling step of filling the metal, a cutting step of terminating the communication between the weighing hole and the discharge port, and cutting the semi-solid metal in the weighing hole from the remainder by an open end of the weighing hole, The discharging step of discharging the solidified metal and supplying it to the molding apparatus is repeatedly performed, and the discharging port is closed by the outer peripheral surface when the weighing hole and the discharging port are not connected. 2. The semi-solid casting method according to 1. 3. A semi-solidification device for holding a metal in a semi-solid state, a part of the semi-solid metal in the semi-solidification device is filled into a weighing hole of a receiving member, and then the weighing is performed by moving the receiving member. The semi-solid metal in the hole is cut from the remainder by the receiving member itself, a predetermined amount of the semi-solid metal is weighed, and thereafter, a weighing device for discharging the semi-solid metal in the weighing hole, and the weighing device is discharged from the weighing device. A molding apparatus for molding semi-solid metal, and a semi-solid casting apparatus comprising: 4. The semi-solid casting apparatus according to claim 3, wherein said receiving member is a rotating body having an outer peripheral surface capable of closing an outlet of said semi-solid apparatus and said weighing hole being opened in said outer peripheral surface. .