JP3383881B2 - Sand mold surface heating device for casting method of thin complex products with sand mold - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to relates to a sand mold surface heating device of the casting how thin complex shaped articles by sand mold.

[0002]

2. Description of the Related Art Conventionally, casting a casting product such as a stainless cast steel or an aluminum alloy having an extremely thin complex shape having a thickness of about 3 mm or less with a normal sand mold has been difficult due to the difficulty of the molten metal flow. It is considered to be almost impossible, and the production of this kind of shaped product is performed by precision machining, welding of complicated drawing members, or by the known lost wax casting method in the case of relatively mass production. There was a way.

[0003]

However, as is well known, the manufacturing method by machining or drawing requires extremely high cost, and it is prohibited to deal with general products, and the lost wax method is also a wax. However, the cost is not suitable for small and medium-volume production which is usually required.

The present invention has been made in view of the above situation, and as a result of years of experimental research conducted by the present inventors, a conventional inexpensive sand mold produces a good casting surface with almost no wrinkles. It is intended to provide a sand mold heating apparatus of the resulting casting how.

[0005]

A solution for the] Therefore, in the present invention, by the provision of the following sections (1) or (2) sand-type heating apparatus of casting how thin complex shaped articles by sand mold shown in the object Is to achieve.

( 1 ) A propane gas heat source, a combustion chamber thereof, a hot air tank for the combustion gas, and a hot air blower for supplying the hot air from the hot air tank into a predetermined sand mold, and part of the hot air tank. Is a suction hose connection for sucking the gas in the runner, which is pressed and released by pouring the sand mold when the combustion is stopped, from the feeder port of the sand mold by the hot air blower when the combustion is stopped to release it to the outside. A sand mold surface heating device for a method of casting a thin-walled complex-shaped product by a sand mold, characterized by having a portion.

( 2 ) In the method for casting a thin-walled complex-shaped product with a sand mold as described in the above item ( 1 ), the hot air uses electric means by a power source instead of a propane gas heat source and its combustion chamber. Sand type surface heating device.

[0008]

The adoption of the action / effect] above present onset Ming mold heating device, hot water wrinkles were problems of the prior art also little, a product having a good casting surface, conventional the shaving,
We have made it possible to produce small and medium lots at a far cheaper cost than either of the products made by welding of drawn products or the lost wax casting method.

For this reason, the thin-walled composite of the sand mold according to the present invention is used.
The sand type surface heating device of the casting method for miscellaneous products is, for example, a small lot product made by carving out conventional stainless steel material, a small lot product made by welding of stainless steel plate, or a prototype before the metal model production of precision casting, Furthermore, it is ideal for prototypes prior to the actual production of precision casting.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings .

First, referring to FIGS. 1 and 2, the steps of the method for manufacturing a sand-shaped thin-walled complex-shaped product according to the present invention will be described.
FIG. 1 shows a cross-sectional view of the sand mold surface heated, and FIG. 2 shows a cross-sectional view of the sand mold in a pouring preparation state. Also in Figure 3, it engages the present invention
Of a sand mold surface heating device for use in carrying out a casting method
Each (a) a side view of a schematic diagram of an embodiment, showing the (b) a plan view.

(Structure of Sand Mold) In FIG. 1, reference numeral 1 denotes a sand mold for casting which is composed of an outer mold 1a and a core (inner mold) 1b of a relatively small and thin product having a complicated shape. 2 is the pouring spout, 2a is the pouring spout lid, 3 is a so-called "weir" part, and 4 is the sprue spout. 5 is
It is a mold surface thermometer provided outside the sand mold 1, and the insertion detection bar 6 can be inserted from the outside into the inner surface adjacent portion of the outer mold 1a to detect the surface temperature thereof.

(Sand Mold Heating) The sand mold 1 is usually air-dried or appropriately heat-dried, and will be described later with reference to FIG. 3, for example, immediately before pouring a molten metal fluid (hereinafter abbreviated as “hot water”) from the spout 2. Sand type heating device 2
One flexible hot air blow pipe 21 of 0 is connected via the hot air supply lid member 8 on the feeder port 4 having the hot air adjusting valve 8,
Surface temperature of the inner and outer sand molds 1b and 1a is 180 ± 10 ℃
Heat to

(Pressurized Gas Suction) Next, as shown in FIG. 2, the hot air supply lid 7 is removed,
Instead of this, a sand mold lid 9 is attached on the feeder port 4.

The sand mold lid 9 is provided with a cylindrical up-water prevention member 10 in the center thereof to prevent the hot water from being sucked by the filter member 10a of the suction port 10b at the bottom and to be pressed by pouring the hot water. In order to promptly inhale and discharge the generated gas to facilitate smooth bathing, a suction pipe 11 made of the same material as the mold product material (hot water) is provided above the gas, as will be described later with reference to FIG. 3 (b), for example. The gas is simultaneously sucked by a hot air blower (rotary blower) 26, which is connected to a part of the hot air tank 25 of the sand mold heating device 20 which is in a non-heated state and driven by an attached motor 27.

(Operation) Although the cast product of the embodiment of the present invention as described above has been described as a comparatively small product, a predetermined sand mold heating and gas suction may not be performed depending on the size or the complexity of the shape. Needless to say, as in the present embodiment, it is possible to feed hot air or suck the pressing gas through a plurality of inlets instead of a single inlet.

[0017] [an embodiment of a heating apparatus] Next, an embodiment of a sand mold surface heating apparatus 20 used in the present invention production process. The sand-type heating device of the present embodiment is characterized in that it can be used not only for heating but also for sucking the pressure gas at the time of pouring.

The schematic structure will be described with reference to FIGS. 3 (a) and 3 (b). (A) is a side view and (b) is a plan view.

(Structure) In FIG. 3, reference numeral 20 denotes a sand-type surface heating device of the present embodiment, and a plurality (four in the illustrated example) of flexible hot air blowers 2
1 is provided.

The present apparatus comprises a propane gas cylinder 23 as a heat source, a burner chamber 24, a hot air tank 25 for storing high temperature air of about 300 ° C., and a high temperature of the propane gas cylinder 23 as a heat source on a carriage supported by four transportation wheels 22. A hot air blower (rotary blower) 26 for sending air under pressure, an electric motor 27 for driving the hot air blower 26, a hot air pipe 28, a switchboard 29, and the like are provided.

Inside the burner chamber 24, the left and right gas burners 30 are provided, the left and right gas regulators 31 are provided with the respective gas regulating fans 31a, and the temperature between the burner chamber 24 and the hot air tank 25 is increased. A sensor 32 and an on-off valve 33 are provided. In addition, the switchboard 29 has a temperature controller 3
4 and a thermometer 35.

The sand-type heating device 20 has a plurality (four in the illustrated example) of flexible hot air blast pipes 21 each having a pressure gauge 21a branched from the hot air pipe 28. Alternatively, the connection portion of the suction hose 36 capable of simultaneously supporting the heating of a plurality of sand molds and connecting to the pressing gas suction pipe 11 required at the same time as the pouring shown in FIG. By being provided in a part of the tank 25 and provided with an opening / closing valve 37, an air cleaner 38 for sucking gas, a suction pressure gauge 39, etc., the present apparatus 20 is provided with both necessary functions in the casting method.

(Other Embodiments) The apparatus of the present embodiment employs relatively inexpensive propane gas as a heat source for heating, but the present invention is not limited to this, and it is also possible to use electric heat. Of course, it doesn't matter.

[0024]

As described above, according to the present invention,
When casting a thin-walled complex-shaped product with a sand mold, prior to pouring the molten metal, both surfaces of the sand mold's outer mold and inner mold are preheated to a predetermined temperature range, and at the same time, the gas pressed by the melt is sucked As a result, the conventional sand mold has enabled casting with a good casting surface free from wrinkles, which was not possible with the conventional method.

For this reason, particularly at the time of relatively small lot production, it is extremely low cost in place of the conventional machining process or partial drawing process, or the lost wax method which is expensive and unsuitable for small and medium volume production. It became possible to deal with it.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a heating state of a sand mold surface of an example.

FIG. 2 is a cross-sectional view of the sand mold of the embodiment in a pouring preparation state.

FIG. 3 is a schematic configuration diagram of a sand mold surface heating device of an embodiment,
(A) Side view, (b) Plan view

[Explanation of symbols]

1 sand mold 1a External type 1b Core (internal type) 2 gate 2a Faucet 3 weirs 4 riser 5 Surface thermometer 6 Insertion detection bar 7 Hot air supply lid 8 hot air regulating valve 9 sand mold lid 10 Water rising prevention member 10a filter member 10b suction port 11 Suction pipe 20 Sand type surface heating device 21 Flexible hot air blower 22 wheels 23 Propane gas cylinder 24 burner room 25 hot air tank 26 hot air blower 27 motor 28 hot air tube 29 switchboard 30 gas burner 31 Gas regulator (left and right) 31a Gas adjustment fan 32 Temperature sensor 33 on-off valve 34 Temperature controller 35 thermometer 36 Suction hose 37 on-off valve 38 Suction air cleaner 39 Suction pressure gauge

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B22C 9/12 B22D 23/00 B22D 18/06

Claims (2)

(57) [Claims] 1. A propane gas heat source, a combustion chamber for the propane gas, a hot air tank for the combustion gas, and a hot air blower for supplying the hot air from the hot air tank into a predetermined sand mold, and a part of the hot air tank. A suction hose connection portion for sucking the gas in the runner, which is pressed and released by pouring the sand mold when the combustion is stopped, from the sand mouth of the sand mold by the hot air blower when the combustion is stopped to release the gas to the outside A sand mold surface heating device for a method of casting a thin-walled complex-shaped product by a sand mold, comprising: Wherein said hot air, propane gas heat source, instead of the combustion chamber, sand the surface of the casting method of the thin-walled complex shape product according to claim 1 sand type, wherein the employing the electrical means by power Heating device.