Abstract: A furnace includes: a furnace body; a housing rotary body including a plurality of side walls, a plurality of housing chambers partitioned by the side walls and disposed circumferentially in multiple stages, each including multiple housing chambers, and a space disposed in the central portion of the housing rotary body to provide a donut shape in plan view; a rotary driving device for rotating the housing rotary body; a heating device for heating the air inside the furnace body; a first and a second partition wall which together partition the inside of the furnace body into the first and the second zone; a first flow passage communicating a blowout port of the fan with outer circumference sides of the housing chambers in the first zone; and a second flow passage communicating outer circumference sides of the housing chambers in the second zone with a suction port of the fan.

Abstract: A vortex chamber includes an outer circumference wall, a container, an annular shoal portion provided between the container and the outer circumference wall so as to encircle the outer circumference of the container, and a dam portion protruding upward from the upper surface of the outer circumference of the container so as to partition the container from the shoal portion. An undried nonferrous metal block is fed into the shoal portion, the block having such a size that is not completely submerged into the molten metal in the shoal portion. The fed nonferrous metal block is gradually melted to have a reduced volume of small pieces and particles of nonferrous metal, which are re-circulated in the shoal portion, flown over the dam portion, and dropped into the container, thereby forming a vortex in the container in which remaining small pieces and particles submerged into the molten metal are melted.

Abstract: A vortex chamber includes an outer circumference wall, a container, an annular shoal portion provided between the container and the outer circumference wall so as to encircle the outer circumference of the container, and a dam portion protruding upward from the upper surface of the outer circumference of the container so as to partition the container from the shoal portion. An undried nonferrous metal block is fed into the shoal portion, the block having such a size that is not completely submerged into the molten metal in the shoal portion. The fed nonferrous metal block is gradually melted to have a reduced volume of small pieces and particles of nonferrous metal, which are re-circulated in the shoal portion, flown over the dam portion, and dropped into the container, thereby forming a vortex in the container in which remaining small pieces and particles submerged into the molten metal are melted.

Abstract: A furnace includes: a furnace body; a housing rotary body including a plurality of side walls, a plurality of housing chambers partitioned by the side walls and disposed circumferentially in multiple stages, each including multiple housing chambers, and a space disposed in the central portion of the housing rotary body to provide a donut shape in plan view; a rotary driving device for rotating the housing rotary body; a heating device for heating the air inside the furnace body; a first and a second partition wall which together partition the inside of the furnace body into the first and the second zone; a first flow passage communicating a blowout port of the fan with outer circumference sides of the housing chambers in the first zone; and a second flow passage communicating outer circumference sides of the housing chambers in the second zone with a suction port of the fan.

Abstract: A recess is formed on the periphery of each of through-holes that go through a rim cavity, and the outer surface of a rim part is cut while a seal member for sealing the through-hole is positioned on the recess. It is thereby possible to stably manufacture a vehicle wheel in which swarf tends not to remain inside the rim cavity. Furthermore, it is not necessary to avoid the seal member for sealing the through-hole when cutting the outer surface of the rim part, and the outer surface of the rim part can be cut without any distinction having to be made between the periphery of the through-hole and the rest of the outer surface. Any increase in manufacturing costs can be minimized.

Abstract: A recess is formed on the periphery of each of through-holes that go through a rim cavity, and the outer surface of a rim part is cut while a seal member for sealing the through-hole is positioned on the recess. It is thereby possible to stably manufacture a vehicle wheel in which swarf tends not to remain inside the rim cavity. Furthermore, it is not necessary to avoid the seal member for sealing the through-hole when cutting the outer surface of the rim part, and the outer surface of the rim part can be cut without any distinction having to be made between the periphery of the through-hole and the rest of the outer surface. Any increase in manufacturing costs can be minimized.