| 摘要 |
FIELD: machine building.SUBSTANCE: impeller of Francis type includes rim 1 with rotation symmetry about rotation axis Z of impeller and bent blades 21, 22, which are rigidly attached to rim 1, each of which includes external peripheral edge 212, 222 and internal central edge 211, 221. Connection points B, Bof rim 1 with internal central edges 211, 221 of blades 21, 22 are located on one and the same circle Ccentred relative to above mentioned axis Z. Connection points A, Aof rim 1 with external peripheral edges 212, 222 of blades 21, 22 are located at least on two different circles C, Ccentred relative to axis Z.EFFECT: reduction of the cost of composite elements of devices owing to limiting their dimensions by reducing the action on them of radial stresses under unsteady conditions.11 cl, 4 dwg |
