Casting apparatus and method for producing castings using it

Patent metadata

Field	Value
Publication number	US-9950363-B2
Application number	US-201415025600-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Sep 30, 2013
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

A casting apparatus for producing a casting by pouring a metal melt into a gas-permeable casting mold by gravity, comprising: a gas-permeable casting mold comprising a cavity including a sprue composed of a tubular portion and a cup portion having a larger diameter than that of the tubular portion to receive the metal melt, a runner constituting a flow path of the metal melt supplied through the sprue, and a product-forming cavity to be filled with the metal melt sent through the runner; a means for pouring the metal melt into the sprue by gravity; a gas-blowing unit comprising a gas-ejecting member to be connected to the sprue; and a mechanism for moving the gas-ejecting member; the gas-ejecting-member-moving mechanism placing the gas-ejecting member at a position just above the tubular portion and not interfering with gravity pouring of the metal melt, and moving it downward for connection to the tubular portion; the gas-blowing unit having blowing a gas to fill the product-forming cavity with the metal melt.

First claim

What is claimed is:

1. A casting apparatus for producing a casting by pouring a metal melt into a gas-permeable casting mold by gravity, comprising:
a gas-permeable casting mold comprising a cavity including a sprue composed of a tubular portion and a cup portion having a larger diameter than that of the tubular portion to receive the metal melt, a runner constituting a flow path of the metal melt supplied through the sprue, and a product-forming cavity to be filled with the metal melt sent through the runner;
a means for pouring the metal melt into the sprue by gravity;
a gas-blowing unit comprising a gas-ejecting member to be connected to the sprue; and
a mechanism for moving the gas-ejecting member;
the gas-ejecting-member-moving mechanism placing the gas-ejecting member at a position just above the tubular portion and not interfering with gravity pouring of the metal melt, and moving it downward for connection to the tubular portion; and
the gas-blowing unit blowing a gas to fill the product-forming cavity with the metal melt, wherein the cup portion extends in one direction from the tubular portion.

2. The casting apparatus according to claim 1 , wherein the gas-ejecting member is placed by the gas-ejecting-member-moving mechanism such that a gas-ejecting port of the gas-ejecting member is below an upper edge of the cup portion.

3. The casting apparatus according to claim 1 , wherein the gas-ejecting member is placed by the gas-ejecting-member-moving mechanism such that a gas-ejecting port of the gas-ejecting member comes into contact with the metal melt residing in the cup portion.

4. The casting apparatus according to claim 1 , wherein the gas-ejecting member is a tapered nozzle capable of being inserted into the tubular portion.

5. The casting apparatus according to claim 1 , wherein the pouring means enables a stream of the pouring metal melt to move between a position just above or near the tubular portion and a position away from the tubular portion within a region of the cup portion.

6. The casting apparatus according to claim 1 , wherein the cup portion has a racetrack shape.

7. The casting apparatus according to claim 1 , wherein the cup portion becomes gradually shallower as separating from the tubular portion.

8. The casting apparatus according to claim 1 , further comprising a means for detecting a surface of the metal melt residing in the sprue, and outputting the detected signal; and a gas-ejecting-member-position-controlling means for receiving the signal output from the melt-surface-detecting means, and driving the gas-ejecting-member-moving mechanism to move the gas-ejecting member according to the signal.

9. A method for producing a casting comprises the steps of:
pouring a metal melt by gravity into a gas-permeable casting mold comprising a cavity including a sprue composed of a tubular portion and a cup portion having a larger diameter than that of the tubular portion to receive the metal melt, a runner constituting a flow path of the metal melt, wherein the cup portion extends in one direction from the tubular portion supplied through the sprue, and a product-forming cavity to be filled with the metal melt sent through the runner; and then blowing a gas into the cavity of the gas-permeable casting mold from a gas-ejecting member of a gas-blowing unit, to fill the product-forming cavity with the metal melt; wherein
the gas-ejecting member is placed at a position just above the tubular portion and not interfering with gravity pouring of the metal melt, and moved downward to the sprue for connection to the tubular portion after gravity-pouring ends.

10. The method for producing a casting according to claim 9 , wherein the gas-ejecting member is placed such that a gas-ejecting port of the gas-ejecting member is below an upper edge of the cup portion.

11. The method for producing a casting according to claim 9 , wherein the gas-ejecting member is placed such that a gas-ejecting port of the gas-ejecting member comes into contact with the metal melt residing in the cup portion.

12. The method for producing a casting according to claim 9 , further comprising the steps of placing a stream of the metal melt poured from a pouring means just above or near the tubular portion at an early stage of a pouring step, and moving the stream away therefrom within a region of the cup portion at an late stage of the pouring step.

13. The method for producing a casting according to claim 9 , further comprising the step of controlling the position of the gas-ejecting member of the gas-blowing unit according to a surface position of the metal melt residing in the sprue.

Assignees

• Hitachi Metals Ltd

Inventors

• Kawabata Masahide
• Iwanaga Toru
• Suehara Kiyoshi
• Morita Yutaka
• Kokubo Masafumi

Classifications

• B22D41/58

  with gas injecting means · CPC title

• B22D27/13 Primary

  making use of gas pressure · CPC title

• B22D18/04

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

• B22D27/09

  by using pressure · CPC title

• B22D18/02 Primary

  Pressure casting making use of mechanical pressure devices, e.g. cast-forging (B22D18/04 takes precedence) · CPC title