Casting device and casting method

Patent metadata

Field	Value
Publication number	US-10286449-B2
Application number	US-201515552695-A
Country	US
Kind code	B2
Filing date	Feb 24, 2015
Priority date	Feb 24, 2015
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

A casting device includes: a split mold for forming a cavity, including a lower mold, a middle mold that slides in a horizontal direction on the lower mold and an upper mold; a split case for forming a chamber, including a lower case to which the lower mold is attached and an upper case to which the upper mold is attached; a chamber suction device that reduces a pressure at least in the chamber through a chamber pipe that is connected to the chamber and extends to an outside of the chamber; and a cavity suction device that reduces a pressure in the cavity through a cavity pipe that is connected to the cavity and extends to the outside of the chamber. The cavity and the chamber are formed when the middle mold is closed on the lower mold and the split case is closed.

First claim

The invention claimed is:

1. A casting device, comprising:
a split mold configured to form a cavity, comprising a lower mold, a middle mold that slides on the lower mold, and an upper mold;
a split case configured to form a chamber, comprising a lower case to which the lower mold is attached and an upper case to which the upper mold is attached, in which the cavity and the chamber are formed when the middle mold is closed on the lower mold and the split case is closed;
a chamber suction device configured to reduce a pressure in the chamber through a chamber pipe that is connected to the chamber and extends to an outside of the chamber; and
a cavity suction device configured to directly reduce a pressure in the cavity through a cavity pipe that is directly connected to the cavity and extends to the outside of the chamber,
wherein the casting device is configured to produce a molded product by filling the cavity formed by the split mold with molten metal held in a holding furnace disposed below the split mold through a stalk with an upper end connected to a sprue of the split mold and a lower end dipped in the molten metal in the holding furnace,
the casting device further comprises a compressor configured to increase the pressure in the holding furnace to supply the molten metal held in the holding furnace at least to the sprue,
the cavity suction device is configured to supply the molten metal supplied at least to the sprue further to the entire cavity, and
the chamber suction device reduces the pressure in the chamber to an achieved chamber pressure, which is lower than an achieved cavity pressure in the cavity achieved through reducing the pressure in the cavity by the cavity suction device.

2. The casting device according to claim 1 , wherein a through hole is formed in a center part of the upper case, the upper mold is fitted in the through hole so as to be integrated with the upper case, and the cavity pipe is constituted by a through hole formed in the upper mold.

3. The casting device according to claim 1 , wherein when the middle mold is closed, the chamber and the cavity are fluidly disconnected.

4. The casting device according to claim 1 , wherein an internal area of the cavity pipe is un-obstructed.

5. The casting device according to claim 1 , further comprising a molten metal sprue arrival sensor for detecting the molten metal reaching the sprue and a controller that controls the cavity suction device based on an input from the molten metal sprue arrival sensor.

6. A casting method which is used to produce a molded product by filling a cavity formed by a split mold with molten metal held in a holding furnace disposed below the split mold through a stalk with an upper end connected to a sprue of the split mold and a lower end dipped in the molten metal in the holding furnace, comprising:
Step (1) of using the split mold configured to form the cavity, the split mold comprising a lower mold, a middle mold that slides on the lower mold and an upper mold, and a split case configured to form a chamber, the split case comprising a lower case to which the lower mold is attached and an upper case to which the upper mold is attached, to close the middle mold on the lower mold and to close the split case so as to form the cavity and the chamber;
after Step (1), Step (3) of reducing a pressure in the chamber to an achieved chamber pressure by means of a chamber suction device through a chamber pipe that is connected to the chamber and extends to an outside of the chamber; and
after Step (1), Step (4) of directly reducing a pressure in the cavity to an achieved cavity pressure by means of a cavity suction device through a cavity pipe that is directly connected to the cavity and extends to the outside of the chamber,
wherein the method further comprises: after Step (1) and before Step (3) and Step (4), Step (2) of increasing a pressure in the holding furnace by means of a compressor to supply the molten metal held in the holding furnace at least to the sprue,
wherein, in Step (4), the molten metal supplied at least to the sprue is supplied further to the entire cavity and the achieved chamber pressure of the pressure in the chamber is lower than the achieved cavity pressure of the pressure in the cavity.

7. The casting method according to claim 6 , wherein in the step (2), a molten metal sprue arrival sensor detects the molten metal reaching the sprue, and in the step (4), a controller controls the cavity suction device based on an input from the molten metal sprue arrival sensor to supply the molten metal supplied at least to the sprue further to the entire cavity.

Assignees

• Nissan Motor

Inventors

• Minamiguchi Satoshi
• OKAMURA Giichirou
• Tsuchiya Shinichi
• Sekiguchi Hiroyuki
• Sugiyama Yuuta
• SCHUBELER Carl

Classifications

• B22D18/06 Primary

  Vacuum casting, i.e. making use of vacuum to fill the mould · CPC title

• B22D18/04 Primary

  Low pressure casting, i.e. making use of pressures up to a few bars to fill the mould · CPC title

• B22C9/062

  Mechanisms for locking or opening moulds · CPC title

• B22C9/06

  Permanent moulds for shaped castings (moulds for ingots B22D7/06) · CPC title