| 摘要 |
PURPOSE:To enable transferring amount of fluid corresponding to combustion amount to be mechanically simply varied in a fluid transferring system of a rotary drive body provided with vanes by permitting the vanes to hold a vane angle corresponding to a temperature in the shape change corresponding to the temperature of an alloy memorizing the shape of the vane. CONSTITUTION:A plurality of vanes 5 constituted from thermally reversible shape memorizing alloy such as Cu, Bu system, etc. at the inner end of a support 6 of a rotary drive body 4 are fixedly combined with each other at their root portions such that their vane angles are adjusted by bending the shape meomorizing alloy correspondingly to the temperature variation. When the rotary drive body 4 as an exhaust fan 15 applied to forced exhaust system gas appliance 1 transfers exhaust, the vanes 5 are set to the best condition of blowing efficiency in the maximum combustion to reduce the combustion amount. When exhaust temperature is lowered along with the reduction of the combustion amount, the vanes 5 are inclined forward so that the blowing efficiency is set to be degraded in response to the reduction of temperature. |
