US Patent No. 9,636,743


Patent No. 9,636,743
Issue Date May 02, 2017
Title Dual-chambered Molten Metal Holding Furnace For Low Pressure Casting
Inventorship Kiyata Mochizuki, Fujinomiya (JP)
Assignee TOUNETSU CO., LTD., Fujinomiya-Shi (JP)

Claim of US Patent No. 9,636,743

1. A dual-chambered molten metal holding furnace for a low pressure casting, comprising:
a molten metal storage container partitioning a molten metal holding chamber and a pressurizing chamber on an inside thereof
and is formed of a monolithic refractory material;

a cover plate composed of a steel product that covers a bottom surface, a side surface, and a top surface of the molten metal
storage container via a heat insulation layer and/or a fireproof layer around the circumference of the molten metal storage

a molten metal passage opening provided between the molten metal holding chamber and the pressurizing chamber;
a lifting cutoff valve opening and closing the molten metal passage opening; and
tube heaters placed, respectively, in the interior of the molten metal holding chamber and the interior of the pressurizing

wherein the pressurizing chamber comprises a pressurizing part and a molten metal output part which are communicated with
each other at the bottom thereof, a pressurizing pipe and a molten metal output pipe, each of which is a heat-resistant integral
sintered product molded from a material having impermeability or permeability, are mounted inside the pressurizing part and
the molten metal output part, respectively, a part of the molten metal storage container other than the pressurizing part
is opened to the atmosphere via an air passage part positioned above the fixed molten metal surface level position, whereby,
even when pressurized gas enters a material constituting the molten metal storage container from the pressurizing pipe, the
pressurized gas is released to the outside of the furnace using the air passage part so as to prevent release of the gas to
the molten metal and the occurrence of air bubbles in the molten metal.