Patent ID: 7581334
Filing Date: 2009-09-01
Classification: F26B

Abstract:
1. A drying apparatus for supplying a dryer booth with hot air for drying comprising: a gas burner indirect heat exchanger, wherein a turn down ratio thereof may be controlled; a blower for sending said hot air, heated by said gas burner indirect heat exchanger, to said dryer booth, the blower having an input side and an output side; a blowing duct, disposed between said gas burner indirect heat exchanger and said dryer booth, to guide said hot air sent by said blower to said dryer booth; an exhaust duct for exhausting hot air from the dryer booth; an exhaust blower disposed in the exhaust duct; a first circulating duct, disposed between the exhaust duct and the blowing duct to guide exhausted hot air from the dryer booth back again to the dryer booth, and a second circulating duct that connects to the blowing duct on an upstream side of the gas burner indirect heat exchanger and to the exhaust duct on a downstream side of the exhaust blower; wherein: the blower is disposed in the blowing duct between said gas burner indirect heat exchanger and said dryer booth and directly receives the hot air, heated by said gas burner indirect heat exchanger, on the input side, and the first circulating duct connects to the blowing duct on a downstream side of the blower.