Mitsubishi Heavy Industries Limited

Yuichi Ohtani

Ikuo Okada

Takashi Akaba

Sachio Shimohata

Susumu Miki

Tatsuya Ohira

Osamu Noda

Naoaki Ikeda

Provided is a directional solidification casting apparatus capable of heightening a cooling effect when molten material poured in a mold is directionally solidified. A mold () disposed around a predetermined area is drawn out from a heating chamber () heated above a melting temperature of metals for producing a casting (), and molten metals () held in a cavity () of the mold () are directionally solidified. The directional solidification casting apparatus () comprises a driving rod () by which the mold () is drawn out from the heating chamber (), a gas nozzle () through which a cooling gas is jetted from inside a predetermined area where the mold () is disposed so as to rapidly cool the mold (), and a gas nozzle () through which a cooling gas is jetted from outside the predetermined area where the mold () is disposed so as to rapidly cool the mold (). A baffle () that does not move even when the driving rod () moves up and down is additionally provided. The baffle () blocks radiant heat emitted from the heating chamber ().

Method and apparatus for directionally solidified casting

A nonlinear optical crystal device, a wavelength conversion element, is surrounded with a heat sink having cooling fins. Cartridge heaters for uniformly heating the nonlinear optical crystal device are arranged in the heat sink, and the temperature of the cartridge heater is regulated by a heater controller. Laser light is input into the nonlinear optical crystal device, and delivered therefrom after its wavelength is converted into a shortened wavelength. When the repetition frequency of laser light is high, heating by the heaters is stopped, and cooling is effected with the heat sink. When the repetition frequency of laser light is low, heating by the heaters is carried out to maintain the temperature of the nonlinear optical crystal device to be a temperature at which a conversion efficiency is satisfactory.

Laser wavelength converter

Growing community of inventors

Takasago, Japan

Yuichi Ohtani