| 摘要 |
PROBLEM TO BE SOLVED: To adopt an impaller which is prepared by cutting easily assembled blades from one plate-like material, to a large-sized blower with high speed rotation. SOLUTION: A plurality of blades 1 are cut from one plate-like material. The blades 1 are wound around and attached to a main plate 2 and a side plate 3. In sich an impeller of a multiblade blower, throttle portions are formed on both sides of the blade 1 when it is cut. The throttle portion is formed within the range on a straignt line connecting the centers of the main plate 2 and the side plate 3 to a center of gravity of each blade 1, under the state that the blade 1 is sound around and fixed to the main plate 2 and the side plate 3. A specified spacing (h) is provided between each end of the cut blade 1 and an attaching portion (b) of the blade 1 to be attached to the main plate 2 and the side plate 3. |
