JP2002283035A - Low pressure casting die cooling method, and device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low pressure casting die cooling method and a device thereof in which the cooling time can be shortened compared with that of the natural cooling, the productivity can be improved thereby, the local cooling can be performed compared with water cooling (cooling only with water), and the increase in the cost of a die can be suppressed. SOLUTION: (1) A low pressure casting die cooling method and a device thereof in which a part 25 to be cooled of a low pressure casting die 20 is locally cooled with mist from a side surface facing a cavity 21 of the die. (2) A low pressure casting die cooling method and a device thereof in which parts corresponding to a bolt hole part and a root part of a wheel out of the low pressure casting die 20 for casting a casting wheel is locally cooled with mist from an opposite surface facing the cavity 21 of the die.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cooling mist of a low pressure casting mold.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3 or 4, cooling of a low-pressure casting mold is performed by air (FIG. 3) or water alone (FIG. 4).
I was going. In the air cooling, a cooling air passage 3 is provided on the side of the mold 1 opposite to the cavity 2, and the air is sent into the cooling air passage 3 for cooling. In the water-only cooling, cooling water is sent from a passage 6 to a portion 5 of the mold 4 to be cooled to be cooled.

[0003]

However, the conventional mold cooling has the following problems. With air cooling, the cooling capacity is too low to achieve the desired cooling capacity. for that reason,
It took time to cool the mold, and there was a limit in increasing productivity. With water alone, the cooling capacity is too high,
Although used as an indirect cooling member for a cooling plate in which a channel is dug, the only way to provide a channel at a position distant from the casting and cool the mold as a whole was to take the local cooling. Also, when cooling the mold directly, it is limited to mold parts where the mold temperature rises extremely, and even in this case, it is necessary to dug the back side and use a metal seal, which requires strict processing accuracy, The mold cost was very high. An object of the present invention is to reduce the cooling time as compared with air cooling, to increase productivity, to perform local cooling as compared with water cooling (water alone cooling), and to suppress an increase in die cost. An object of the present invention is to provide a method and a device for cooling a casting mold.

[0004]

The present invention to achieve the above object is as follows. (1) A method of cooling a low-pressure casting mold in which a required cooling portion of the low-pressure casting mold is locally mist-cooled from a side opposite to a cavity of the mold. (2) The low-pressure casting mold according to (1), wherein a portion corresponding to the bolt hole and the base of the wheel in the low-pressure casting mold for casting the casting wheel is locally mist-cooled from the side opposite to the cavity of the mold. Cooling method. (3) a low-pressure casting mold that forms a cavity inside;
A low-pressure casting mold cooling device, comprising: a mist spray nozzle for locally spraying a mist from a side opposite to a cavity of the mold toward a portion requiring cooling of the mold. (4) The low-pressure casting die according to (3), wherein the mist injection nozzle is arranged so as to face a side opposite to a cavity of a portion corresponding to a bolt hole portion and a base portion of the wheel in a low-pressure casting die for casting a casting wheel. Mold cooling device.

In the cooling method of the low-pressure casting mold of (1) and (2) and the cooling device of the low-pressure casting mold of (3) and (4), mist cooling is used instead of the conventional air cooling and water cooling. Therefore, the cooling capacity is high and the required cooling area of the mold can be cooled in a short time, and the productivity can be increased.Moreover, the required cooling area of the mold can be locally cooled, and it is necessary to dig a channel in the mold. Therefore, an increase in die cost can be suppressed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method and an apparatus for cooling a low-pressure casting mold according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, a low-pressure casting mold cooling apparatus 10 according to an embodiment of the present invention includes a low-pressure casting mold 20 having a cavity 21 formed therein, and cooling of the low-pressure casting mold 20 from the side opposite to the cavity 21. A mist spray nozzle 30 for locally spraying mist toward the part 25.

The low-pressure casting mold 20 is, for example, a low-pressure casting mold for an aluminum alloy wheel for an automobile. In the case of a wheel low-pressure casting mold, the mold 20 includes an upper mold 22, a lower mold 23, a horizontal mold 24, and the like. In the case of a wheel low-pressure casting mold, the required cooling portion 25 of the mold 20 includes a base portion (intersection between the rim and the disc) corresponding portion 26 and a bolt hole corresponding portion 2.
7, an outer peripheral corresponding portion 28, and the like. The cooling required portion 25 of the mold 20 is a portion corresponding to a thick portion (a portion that is difficult to cool) of the wheel. The cooling required portion 25 of the mold 20 is locally cooled to uniformly solidify the entire wheel. I do.

The mist spray nozzle 30 may have any structure as long as it generates and sprays mist (fine particles of water) from water and air. For example, it is possible to use a mist generation nozzle having a structure in which water is sent to each mist injection nozzle 30 by the water pipe 31 and air is sucked from the air pipe 32 by each mist injection nozzle 30 to convert the water into mist. Since the mist sprayed from the mist spray nozzle 30 reaches the surface of the mold at the opposing part, the latent heat of vaporization (540 cal / g) is taken from the surface of the mold and vaporized.
The cooling capacity is much greater than water alone cooling and air cooling, and instantaneous cooling and local cooling are possible.

The method of cooling a low-pressure casting mold according to the embodiment of the present invention comprises a method of locally mist-cooling a required cooling portion 25 of the low-pressure casting mold 20 from the side opposite to the cavity 21 of the mold. When the low-pressure casting mold is the low-pressure casting mold 20 for casting a casting wheel, the method of cooling the low-pressure casting mold is to mold the portions 26 and 27 of the mold 20 corresponding to the bolt hole and the base of the wheel. It is a cooling method in which mist is locally cooled from the side opposite to the cavity 21 of the mold.

Next, the method of cooling the low-pressure casting mold of the embodiment of the present invention and the operation of the apparatus will be described. Taking an aluminum alloy wheel for automobiles as an example of a casting work, it was manufactured by low-pressure casting, and cooling was performed in the case of mist cooling of the present invention and in the case of conventional air cooling and water cooling, and a comparison was made.

The results are shown in the following table. Cooling method Cycle time Cast appearance Remarks The present inventionExample 1 Mist main body 4 min / 1 piece No defect OK Cooling maximum 2 Mist main body 4.5 minutes / 1 piece No defect OK 3 Mainly mist 4.8 min / 1 piece No defect OK Conventional methodAir-cooled 1 Mainly air-cooled 10 minutes / 1 piece No defect OK Maximum cooling Air-cooled 2 Mainly air-cooled 8.5 min / 1 piece Conventional methodWater-cooled 1 Mainly water-cooled 7 minutes / 1 piece No defect OK Water-cooled 2 Mainly water-cooled 3.5 min / 1 Root nest failure occurred Maximum cooling

As can be seen from the above table, the conventional methods of air cooling and water cooling require a cycle time of 10 minutes / 1 piece and 7 minutes / 1 piece in order to produce a good-quality product. If this is done, the cycle time can be shortened, but appearance defects will occur. On the other hand, in the case of the mist-based method of the present invention, good-quality products were produced even when the cooling was maximized, and a cycle time of 4 minutes / 1 piece was possible. From this, it was found that productivity could be increased while maintaining quality. Further, since there is no need to dig a water cooling passage in the mold, the cost of the mold does not increase.

[0013]

According to the low-pressure casting mold cooling method of the first and second aspects and the low-pressure casting mold cooling apparatus of the third and fourth aspects, mist cooling is used instead of conventional air cooling and water cooling.
Cooling ability is high and can cool the mold requiring cooling in a short time,
The cycle time of casting-mold cooling can be shortened, and productivity can be increased. In addition, it is possible to locally cool a part of the mold requiring cooling. Thereby, the condition of the directional solidification can be given to the mold. Further, since the mold is cooled from the side opposite to the cavity, the quality of the casting does not deteriorate. In addition, since it is not necessary to dig a waterway in the mold, it is only necessary to arrange pipes around the mold, and it is possible to suppress an increase in mold cost.

[Brief description of the drawings]

FIG. 1 is a sectional view of an apparatus for performing a method of cooling a low-pressure casting mold according to an embodiment of the present invention.

FIG. 2 is a piping diagram of an apparatus for performing a method for cooling a low-pressure casting mold according to an embodiment of the present invention.

FIG. 3 is a sectional view of a conventional cooling device for a low-pressure casting mold in the case of air cooling.

FIG. 4 is a sectional view of a conventional cooling device for a low-pressure casting mold in the case of water cooling.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Low-pressure casting mold cooling device 20 Low-pressure casting mold 21 Cavity 22 Upper die 23 Lower die 24 Horizontal die 25 Cooling required part 26 Base part (crossing part of rim and disk) corresponding part 27 Bolt hole corresponding part 28 Peripheral part corresponding Part 30 Mist spray nozzle 31 Water pipe 32 Air pipe

Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) B60B 3/06 B60B 3/06 (72) Inventor Yoshimichi Nakamura 5-9, Yonbancho, Chiyoda-ku, Tokyo Topy Industries Co., Ltd. In-company (72) Inventor Yoshiharu Mizushima 5-9, Yonbancho, Chiyoda-ku, Tokyo Topy Industries, Ltd. F-term (reference) 4E093 NB05 VA01

Claims (4)

[Claims] 1. A method of cooling a low-pressure casting mold in which a required cooling portion of the low-pressure casting mold is locally mist-cooled from a side opposite to a cavity of the mold. 2. The low-pressure casting according to claim 1, wherein a portion of the low-pressure casting mold for casting the casting wheel, which corresponds to the bolt hole and the base of the wheel, is locally mist-cooled from the side opposite to the cavity of the mold. Mold cooling method. 3. A low-pressure casting mold comprising: a low-pressure casting mold having a cavity formed therein; and a mist spray nozzle for locally spraying a mist from a side of the mold opposite to the cavity toward a portion requiring cooling of the mold. Cooling device for casting mold. 4. The low-pressure casting die according to claim 3, wherein the mist injection nozzle is arranged so as to face a side opposite to a cavity of a portion corresponding to a bolt hole portion and a base portion of the wheel in a low-pressure casting mold for casting a casting wheel. Cooling device for casting mold.