Patent ID: 7377774
Filing Date: 2008-05-27
Classification: F27B,F27D

Abstract:
1. A change-over apparatus for a cooling gas passage in a vacuum heat treating furnace for cooling a heated article to be treated with a pressurized circulation gas, comprising a cooling chamber surrounding a cooling zone in which the article to be treated is stationarily placed, and a gas cooling and circulating system for cooling and circulating a gas passing through the cooling chamber, wherein the apparatus further comprises: a stationary partition plate partitioning between the cooling chamber and the gas cooling and circulating system, and a slidable shield plate adapted to be slidably driven along an outer surface of the stationary partition plate, the stationary partition plate having a suction opening and a discharge opening which are independently communicated, respectively, with a suction port and a discharge port of the gas cooling and circulating system, the slidable shield plate having a shield part which partially shield the suction opening and the discharge opening of the stationary partition plate, to thereby alternately change over a direction of the gas passing through the cooling chamber.