JP2004025259A - Casting apparatus and method with metallic mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the bending of a product caused by the shrinkage of a feeder head part at the opening time of metallic molds, related to a casting apparatus with the metallic molds. <P>SOLUTION: In the apparatus 10 with the metallic molds, in which the mutually faced metallic molds 17, 18 can be closed/opened and the cast product is formed by cooling and solidifying molten metal poured into a cavity 31 with both metallic molds 17, 18 closed, a cooling means 40 for cooling the feeder head part 2 connected with the product 1 is arranged in the metallic mold 17 where the product 1 is left with both metallic molds 17, 18 opened. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a mold casting apparatus and method.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a mold casting apparatus, there is a mold casting apparatus in which opposing dies can be clamped / unmolded and a molten metal poured into a cavity in a state where both dies are clamped is cooled and solidified to form a cast article. A cast article is composed of a product part, a riser, a runner, and the like that constitute a product. The riser shrinks when the molten metal poured into the cavity in a mold-clamped state of the two molds shrinks and melts. In order to prevent shrinkage cavities from forming, the molten metal is supplied to the shrinkage cavities to form a sound casting.
[0003]
[Problems to be solved by the invention]
In the mold casting apparatus, the riser is constantly replenishing hot water when the molten metal in the cavity solidifies, so the volume of the riser is large enough to supply enough hot water. The solidification end timing of the feeder is set to be later than the solidification end timing of the molten metal in the cavity. For this reason, the heat capacity of the feeder part is large, and therefore, after the mold is opened, the feeder part ends solidification later than the product, and the product is pulled toward the feeder part at the connection part with the feeder part. There is a risk of bending.
[0004]
In particular, when a hollow part is formed in a product using a mold in which a core is placed in a cavity, such as a bottom case of a front fork for a motorcycle or a power cylinder of a power steering for an automobile, the product is heated by a feeder. When the hollow portion is provided in the vicinity of the connecting portion with the feeder, the cross-sectional area of the product at the connecting portion with the feeder becomes much smaller than the cross-sectional area of the feeder, and the above-described bending of the product is likely to occur.
[0005]
An object of the present invention is to prevent a product from being bent due to shrinkage of a feeder unit when a mold is opened in a mold casting apparatus.
[0006]
[Means for Solving the Problems]
The invention according to claim 1 is a mold casting apparatus for forming a cast article by allowing opposite molds to be mold-clamped and mold-openable, and cooling and solidifying a molten metal poured into a cavity in a mold-clamped state of both molds. The cooling means for cooling the feeder portion connected to the product is provided in the mold in which the product remains in the open state of both the molds.
[0007]
According to a second aspect of the present invention, in the first aspect, a core is further arranged in the cavity.
[0008]
According to a third aspect of the present invention, in addition to the first or second aspect, the cooling means comprises an air blowing device, and further includes an electromagnetic valve which starts blowing air from the air blowing device when the mold is opened. It was done.
[0009]
The invention of claim 4 is a mold casting method using the mold casting apparatus according to any one of claims 1 to 3, wherein the mold is opened after pouring the mold into the cavity and the feeder. The feeder is cooled by the cooling means.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a front view showing a mold casting apparatus, FIG. 2 is a front view showing a mold, and FIG. 3 is a cross-sectional view showing a mold opening state of a portion along line III-III in FIG.
[0011]
The mold casting apparatus 10 is for casting a long hollow article such as a bottom case of a front fork for a motorcycle or a power cylinder of a power steering for an automobile, and a base 12 provided on a gantry 11 as shown in FIG. The supporting frame 13 and the fixed frame 14 are fixed on the upper frame, and the moving frame 16 is slidably supported by a tie bar 15 provided so as to connect the supporting frame 13 and the fixed frame 14. A mold 17 is mounted on the fixed frame 14, and a mold 18 is mounted on the movable frame 16. The movable frame 16 is moved toward and away from the fixed frame 14 along the tie bar 15 by a mold clamping cylinder 19 supported on the support frame 13. By doing so, the molds 17 and 18 can be closed / opened.
[0012]
The mold casting apparatus 10 forms a cavity 31 (FIGS. 2 and 3) in a state in which the molds 17 and 18 are clamped, and the metal core 20 made of iron or the like can be arranged in the cavity 31. The core 20 forms a hollow portion of a hollow elongated article. A guide bar 21 is fixed to the lower surface of the base 12, and an elevating table 22 guided by the guide bar 21 can be moved up and down by a core elevating cylinder 23 (not shown) provided on the upper surface of the base 12. The core 20 is connected to a core mounting member 24 fixed to the elevating platform 22, guided by a core guide member 25 fixed to the dies 17, 18, and moved up from the standby position to the working position by being lifted. 31. In the working position, the core 20 is centered and supported by a center pin 27 which is moved up and down by a center cylinder 26.
[0013]
As shown in FIGS. 2 and 3, the two dies 17 and 18 connect the feeder 32 to the upper end and the lateral side (the portion corresponding to the overlay portion of the product 1) of the cavity 31. A sprue 34 is connected to a sprue 34 via a sprue 33. The molten metal poured into the cavity 31 solidifies to form a product (a hollow elongated article such as a bottom tube) 1. The feeder 32 constantly replenishes the molten metal poured into the cavity 31 in order to prevent the molten metal from shrinking and forming a shrinkage cavity in the product 1 when the molten metal is solidified. The hot water forms a feeder 2 connected to the product 1.
[0014]
The cooling means 40 for cooling the feeder unit 2 connected to the product 1 is provided in the one of the two dies 17 and 18 in which the product 1 remains in the opened state. The cooling means 40 is configured by providing an air blowing device 42 on a cooling insert 41 installed in the mold 17. The air blowing device 42 is arranged such that the air blowing direction of the outlet 43A of the compressed air supply passage 43 formed in the cooling insert 41 is directed toward the feeder 32 of the mold 17, and the electromagnetic valve is provided in the compressed air supply passage 43. 44 (not shown). The solenoid valve 44 is turned on by the output of a sensor that detects the mold opening for a certain period of time when the molds 17 and 18 are opened, opens the valve, and compresses the air from the outlet 43A toward the feeder 32. Spray cooling air.
[0015]
Therefore, the casting operation by the mold casting apparatus 10 is performed as follows.
(1) The core 20 is raised from the standby position to the working position by the core lifting cylinder 23.
[0016]
(2) The core 20 is centered and supported by the center pin 27 of the center cylinder 26.
[0017]
(3) The molds 17 and 18 are clamped by the mold clamping cylinder 19 to form the cavity 31. The core 20 described in (1) above is arranged inside the cavity 31.
[0018]
(4) Pouring the cavities 31 from the gates 34 of both dies 17 and 18 via the runner 33 and the feeder 32.
[0019]
(5) The center pin 27 of the center cylinder 26 is removed from the core 20, for example, 60 seconds after the pouring.
[0020]
(6) After elapse of, for example, 100 seconds from the pouring, the core 20 is lowered to the standby position by the core raising / lowering cylinder 23 and is extracted from the casting 1.
[0021]
(7) After elapse of, for example, 150 seconds from the pouring, the molds 17 and 18 are opened by the mold clamping cylinder 19.
[0022]
(8) As described above, the feeder 32 is cooled by the air blowing device 42 (blow-out port 43A) of the cooling means 40 for a certain period of time starting immediately after or immediately after the mold opening in (7).
[0023]
(9) Take out the product 1 and the feeder unit 2 from the mold 17, and cut the product 1 from the feeder unit 2.
[0024]
According to the present embodiment, the following operations are provided.
(Actions Corresponding to Claims 1 and 4)
{Circle around (1)} In the mold open state, the feeder unit 2 connected to the product 1 remaining in the one mold 17 is cooled by the cooling means 40. Thus, even if the temperature of the feeder unit 2 immediately after opening the mold is higher than the temperature of the product 1 and the heat capacity thereof is large, the temperature of the feeder unit 2 is immediately cooled to be equal to the temperature of the product 1, It is possible to prevent a difference in shrinkage from occurring between the hot water unit 2 and the product 1 and to prevent the product 1 from being bent by being pulled toward the feeder unit 2 at a connection portion with the feeder unit 2.
[0025]
(Actions Corresponding to Claims 2 and 4)
(2) A hollow portion is formed in the product 1 using the die casting apparatus 10 in which the core 20 is disposed in the cavity 31, and the product 1 is provided with the hollow portion in the vicinity of a connection portion with the feeder 2. Thus, even if the cross-sectional area of the product 1 is significantly smaller than the cross-sectional area of the feeder 2 at the connection portion with the feeder 2, bending of the product 1 can be prevented by the above (1).
[0026]
(Actions Corresponding to Claims 3 and 4)
(3) By using the air blowing device 42 and the solenoid valve 44 as the cooling means 40, air can be blown to the feeder unit 2 and cooled at the same time as the mold is opened. 2 can be cooled.
[0027]
As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to the embodiments, and there may be a design change or the like without departing from the gist of the present invention. This is also included in the present invention.
[0028]
【The invention's effect】
As described above, according to the present invention, in a die casting apparatus, it is possible to prevent a product from being bent due to shrinkage of a feeder unit when the mold is opened.
[Brief description of the drawings]
FIG. 1 is a front view showing a mold casting apparatus.
FIG. 2 is a front view showing a mold.
FIG. 3 is a cross-sectional view showing a mold opening state of a portion along a line III-III in FIG. 2;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Product 2 Feeder part 10 Die casting apparatus 17, 18 Die 20 Core 31 Cavity 32 Feeder 40 Cooling means 42 Air blowing device 44 Solenoid valve

Claims (4)

In a mold casting apparatus for forming a molded article by cooling and solidifying a molten metal poured into a cavity in a state where both molds are clamped, the molds being opposed to each other being openable.
A mold casting apparatus characterized in that a cooling means for cooling a feeder portion connected to a product is provided in a mold in which a product remains in a mold opened state of both molds. The mold casting apparatus according to claim 1, wherein a core is disposed in the cavity. 3. The mold casting apparatus according to claim 1, wherein said cooling means comprises an air blowing device, and further comprises an electromagnetic valve which starts blowing air from the air blowing device when the mold is opened. A mold casting method using the mold casting apparatus according to any one of claims 1 to 3,
A mold casting method in which the cooling means cools the feeder portion when the molds are opened after pouring into the cavity and the feeder of both dies.

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