JPS58116973A - Low-pressure casting device - Google Patents

Abstract

PURPOSE:To reduce the generation of defective products by providing plural gates communicating from an inflow part for molten metal with cavities spacially, providing heat insulating material layers on the outside circmferential surface and pressong auxiliary pressurizing plates to the inner sides of the cavities by the pressurizing force of the molten metal. CONSTITUTION:Gates 16 communicating with cavities 13 of dies from an inflow part 15 for molten metal are provided spacially, and heat insulting material layers are provided on the outside circumferential surfaces thereof. Auxiliary pressurizing plates 22 are stuck in the recesses of the dies 18 between the gates 16 by means of pressurizing bushings 19, springs 20 and supporting means 21. Molten metal is forced roughly uniformly from the part 15 thrugh the gates 16 into the cavities 13. In this stage, the pressurizing force of the molten metal is exerted upon the bushings 19, and presses the plates 22 via the springs 20, thus the molten metal in the cavities 13 is pressurized uniformly. The layers 17 contribute to solidifying of the molten metal in the gates 16 after solidification of the molten metal in the cavities 13 and to reduction in the remaining molten metal in the gates. Thus the generation of defective cast products is decreased and yield is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a low-pressure casting apparatus, and more particularly to a low-pressure casting apparatus in which layer portions provided at 1161 points communicating from a molten metal inflow portion (pool portion) to a mold cavity are integrated. related to

Conventionally, a low-pressure casting apparatus is formed of an upper mold body 1 and a lower mold body 2, as shown in FIG. 6 and consecutive d
has been done. Therefore, the molten metal passing through the stalk is
The light is adjusted to the area indicated by a thin diagonal line in the figure. In this case, the setting f of 45
IIT-Har is a rounding machine that is constrained by the relationship with the shape of a cracked product, and low-pressure trout compensation 1 = more hesitant - C: The applied pressure does not act uniformly on the mold, resulting in product defects. As shown in Figure 2, the product removed from the mold has a 5 (10,000*
spring.

Furthermore, after the 111th part is hardened in the equipment for one part in the area, the product is taken out from the mold. Since it is too tangled compared to the vertical direction of the part, the -include 1 kuru ρ・★<t'.

Yumei Moto's objective is to reduce the occurrence of product defects by 11/18, and to reduce the write cycle to 541m, which will result in 111 shipments.

The first method of the present invention is to provide a plurality of weirs communicating from the 4EIhft entrance to the main entrance, separated from each other, and to provide a layer of heat insulating material around the outer periphery of these weirs. 2, a plurality of weirs communicating from the molten metal inflow part to the cavity are provided in a nine-shaped configuration, spaced apart from each other, and a heat insulating material layer is provided around the outer periphery of these weirs, and at least a part of the cavity surface of the mold is covered with the molten metal. An auxiliary pressure plate is provided that is pressed against the inside of the cavity by the pressure of the molten metal that is press-fitted from the inlet.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 3, the upper shoe body 11 and the lower shoe body! A core 14 is installed in a cavity 13 formed by 2 and 2. The S* drifter section 15 communicates with the capacity 13 via three weirs 16. A heat insulating material layer 17 is provided around the outer periphery of each base 16, and recesses are formed in the portions of the mold 18 between the respective scoops 16, and pressure bushings 19 are fitted into these recesses so as to be freely insertable. ing.

One end of a spring 2o is fixed to the bottom side of the pressure bushing 19, and the other end of the spring 2o is fixed to an auxiliary pressure &22 via a support 21.

In such a low-pressure casting apparatus, the molten metal press-ined from the stalk by the pressurizing means of the low-pressure casting machine is molten metal inflow i@
After staying at 11s, it passes through each group 16 and is applied to 19, so the pressurizing bush 19 moves while being inserted into the cavity 1311I. Due to this movement of the pressure bush 19, the auxiliary pressure plate 22 is pressed into the cavity 13 via the spring 20.

Due to the action of the auxiliary pressure plate 22, the four hot water in the cavity 13 are almost uniformly pressurized over a wide range on the lower surface side.

Also, since @16 is divided into multiple parts, each weir 16
The cross-sectional area of the flow path is small, or the insulation material Nl17 is provided around the outside of the weir 16, so f8#I! is inside the cavity 13. When I is press-fitted, solidification of the molten metal within the salt 16 can be avoided.

Also, during the period of solidifying the molten metal in the cavity 13, the species 16
Since it is kept warm by the heat insulating layer 17, it does not solidify immediately, but solidifies after the molten metal in the cavity 13 solidifies. Further, even when the molten metal in the weir 16 portion solidifies or solidifies, the molten metal in this portion does not solidify completely because the capacity of the molten metal flow portion Is is large. Therefore, the pressurization is stopped (exhaust: #! The unsolidified molten metal in the molten metal inlet passes through the stalk and returns to the furnace. As a result, the shaved product/fi removed from the mold is shown in Figure 4. The amount of weir residue 23 decreases.

As described above, the present invention has the following effects.

In the first invention, weirs can be arranged in any shape and number;
It is possible to apply pressure directly to parts of the product that are likely to be defective, and there is also a degree of freedom in the placement of the product. Since the molten metal inflow part (9 parts of the hot water pool) that communicates with multiple weirs can be made larger, the remaining part of the weir after the product is removed from the mold can be made smaller, which contributes to energy saving. 7'! :,L.

The heat insulating material layer provided around the outer circumference of the weir can appropriately delay the solidification period of the molten metal in the weir section relative to the solidification period of the molten metal in the cavity, thereby shortening the casting time. Furthermore, since solidification of the molten metal occurs sequentially from the upper part of the cavity to the weir, it is possible to prevent product defects due to directional solidification.

In the second invention, in addition to the effect of the first invention, the pressurizing force of the molten metal in the molten metal flow part acts efficiently and uniformly on the pressurizing of the molten metal in the chamber, thereby preventing the occurrence of product defects. This can be further prevented.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the main part of a conventional low-pressure casting device, Fig. 2 is a cross-sectional view showing the shape of the weir residue rough material produced by the apparatus of Fig. 1, and Fig. 3 is a cross-sectional view of the main part showing an example of the present invention. Figure 4 shows the weir f! by the device shown in Figure 3. 49 is a cross-sectional view showing the shape of the rough material 6゜11...Upper mold body 12...Upper mold body 13.
... Cavity 14 ... Core - 15 ... Molten metal flow part 16 ... Weir 17 ... Insulating material layer
19...Pressure bushing 20...Spring 2
2...Auxiliary pressure plate 23...Remaining weir Figure 1

Claims (1)

[Claims] (Characterized in that 11 melt #11 are provided with 4 numbered parts communicating from the inflow part to the mold cavity, respectively, separated from each other, and a heat insulating material layer is provided around the outer periphery of these parts.) (2) fJl communicating from the molten metal inlet to the mold cavity
45! Weirs are provided in nine positions, spaced apart from each other, and a layer of heat insulating material is provided around the outside of these weirs.
A low-pressure casting apparatus, characterized in that an auxiliary pressure plate is provided on at least a part of the circumferential surface of the cavity, the auxiliary pressure plate being pushed out into the cavity by the pressurizing force of the molten metal press-fitted from the molten metal inlet.