Claims
- 1. An induction melting furnace for heating a melt and discharging a metered amount of the melt, the induction melting furnace comprising:
a melt chamber for heating the melt in the melt chamber; a meter chamber having an outlet, the interior of the melt chamber connected by a connecting passage to the interior of the meter chamber to allow a flow of the melt from the melt chamber to the meter chamber; an at least one induction coil at least partially surrounding the melt chamber and meter chamber; a means for controlling the flow of the melt through the connecting passage; and a means for controlling the discharge of the melt through the outlet, whereby when the meter chamber is filled with the melt and the means for controlling the flow of the melt through the connecting passage prevents flow of the melt from the melt chamber to the meter chamber, the means for controlling the discharge of the melt through the outlet allows the discharge of the melt in the meter chamber.
- 2. The induction melting furnace of claim 1 wherein a magnetic field created by a flow of an ac current in the at least one induction coil inductively heats the melt chamber whereby the heat induced in the melt chamber heats the melt in the melt chamber by conduction.
- 3. The induction melting furnace of claim 1 wherein a magnetic field created by a flow of an ac current in the at least one induction coil inductively heats the melt in the melt chamber.
- 4. The induction melting furnace of claim 1 further comprising a means for adjusting the interior volume of the meter chamber.
- 5. The induction melting furnace of claim 1 further comprising a means for providing a continuous supply of a feedstock to the melt chamber.
- 6. The induction melting furnace of claim 1 wherein the means for controlling the flow of the melt through the connecting passage comprises a first stopper that seats on a surface region of the connecting passage to prevent the flow of the melt from the melt chamber to the meter chamber, and the means for controlling the discharge of the melt through the outlet comprises a second stopper that seats on a surface region of the outlet to prevent the discharge of the melt in the meter chamber.
- 7. The induction melting furnace of claim 6 further comprising:
a first stopper rod attached to the first stopper, the first stopper rod connected to a means for raising and lowering the first stopper to unseat the first stopper from the surface region of the connecting passage, or seat the first stopper on the surface region of the outlet passage, respectively; and a second stopper rod attached to the second stopper, the second stopper rod connected to a means for raising and lowering the second stopper to unseat the second stopper from the surface region of the outlet passage, or seat the second stopper on the surface region of the outlet passage, respectively, the second stopper rod disposed in an interior passage within the first stopper rod and the first stopper, whereby the first stopper can be raised or lowered independently from the raising or lowering of the second stopper.
- 8. The induction melting furnace of claim 7 further comprising a supply of a gas to a space formed between the first stopper rod and the second stopper rod, whereby the gas flows through the space and into the melt in the melt chamber in a region around the first stopper with sufficient pressure to rise through the melt when the first stopper is unseated from the surface region of the connecting passage, and the gas flows into the meter chamber when the first stopper is seated on the surface region of the connection passage.
- 9. The induction melting furnace of claim 7 further comprising a supply of a gas to the connecting passage with sufficient pressure whereby the gas rises through the melt in the melt chamber when the first stopper is unseated from the surface region of the connecting passage, and the gas flows into the meter chamber when the first stopper is seated on the surface region of the connection passage.
- 10. A method of heating a melt and discharging a metered amount of the melt, the method comprising the steps of:
placing the melt in a melt chamber at least partially surrounded by an induction coil; flowing an ac current through the induction coil; connecting the melt chamber to a meter chamber with an connecting passage to allow a flow of the melt into the meter chamber to fill the meter chamber with melt; closing the connecting passage to prevent the flow of the melt from the melt chamber into the meter chamber; and opening an outlet of the meter chamber to allow the discharge of a metered amount of the melt from the meter chamber.
- 11. The method of claim 10 further comprising the steps of:
supplying a gas to the volume over the surface of the melt in the melt chamber by bubbling the gas through the melt in the melt chamber when the connecting passage is opened to allow the flow of the melt from the melt chamber into the meter chamber; and supplying the gas to the volume over the surface of the melt in the meter chamber when the connecting passage is closed.
- 12. The method of claim 10 further comprising the step of adjusting the volume of the meter chamber.
- 13. An induction melting furnace for heating a melt and discharging a metered amount of the melt, the induction melting furnace comprising:
a feed chamber having a sealable supply opening for placing a charge of the melt in the feed chamber, the feed chamber having a sealable delivery opening; a melt chamber for heating the melt in the melt chamber, the melt chamber connected to the feed chamber by the sealable delivery opening, the melt chamber having a melt chamber outlet for discharge of the melt; an at least one induction coil at least partially surrounding the melt chamber; a meter chamber having a meter chamber inlet and a meter chamber outlet, the meter chamber inlet connected to the melt chamber outlet by a connecting passage; a means for opening and closing the connecting passage to control the flow of the melt through the connecting passage; and a means for opening and closing the meter chamber outlet, whereby opening the connecting passage while the meter chamber outlet is closed fills the meter chamber with the melt, and opening the meter chamber outlet while the meter chamber is filled with melt and the connecting passage is closed discharges a metered amount of the melt from the meter chamber through the meter chamber outlet.
- 14. The induction melting furnace of claim 13 wherein a magnetic field created by a flow of an ac current in the at least one induction coil inductively heats the melt chamber whereby the heat induced in the melt chamber heats the melt in the melt chamber by conduction.
- 15. The induction melting furnace of claim 13 wherein a magnetic field created by a flow of an ac current in the at least one induction coil inductively heats the melt in the melt chamber.
- 16. The induction melting furnace of claim 13 wherein the meter chamber is detachably connected to the melt chamber.
- 17. The induction melting furnace of claim 13 further comprising a preheater for preheating the charge prior to placing the charge in the feed chamber.
- 18. The induction melting furnace of claim 13 further comprising a gas system whereby a gas can be selectably supplied to or withdrawn from the feed chamber, selectably supplied to the melt chamber and selectably supplied to or withdrawn from the meter chamber.
- 19. A method of heating a melt and discharging a metered amount of the melt, the method comprising the steps of:
placing the melt in a melt chamber having a melt chamber outlet; surrounding the melt chamber at least partially with a one or more induction coils; flowing an ac current through the one or more induction coils; connecting an inlet of a meter chamber to the melt chamber outlet by a melt chamber outlet valve; connecting an outlet of the meter chamber to a meter chamber outlet value; closing the meter chamber outlet valve and opening the melt chamber outlet value to fill the meter chamber with melt from the melt chamber; and closing the melt chamber outlet valve and opening the meter chamber outlet valve to discharge the metered volume of melt in the meter chamber.
- 20. The method of claim 19 further comprising the steps of:
placing a charge of the melt in a sealable feed chamber, a feed chamber outlet sealable connected to the melt chamber; sealing the feed chamber; and delivering the charge to the melt chamber through the feed chamber outlet.
- 21. The method of claim 20 further comprising the steps of:
injecting a gas into the volume above the melt in the melt chamber; injecting the gas into the feed chamber to approximately the same pressure of the gas injected into the volume above the melt in the melt chamber before delivering the charge to the melt chamber; withdrawing the gas from the feed chamber after delivering the charge to the melt chamber; injecting the gas into the meter chamber when the melt chamber outlet valve is closed and the meter chamber outlet valve is opened to displace the metered volume of melt discharging from the meter chamber; and withdrawing the gas from the meter chamber when the melt chamber outlet valve is opened and the meter chamber outlet valve is closed to permit filling of the meter chamber with melt from the melt chamber.
- 22. The method of claim 20 further comprising the step of preheating the charge before placing the charge in the sealable feed chamber.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/307,200, filed Jul. 23, 2001, and U.S. Provisional Application No. 60/352,979 filed Jan. 30, 2002.
Provisional Applications (2)
|
Number |
Date |
Country |
|
60307200 |
Jul 2001 |
US |
|
60352979 |
Jan 2002 |
US |