GB1066053A - Improvements relating to cross-flow machines for inducing flow of fluids - Google Patents

Abstract

1,066,053. Transverse-flow fans and pumps. HOOVER Ltd. April 22, 1964 [April 22, 1963], No. 15857/63. Heading F1C. In a transverse-flow fan or pump including a cylindrical rotor having blades extending parallel to its axis and mounted to rotate about its axis, and a divider extending the length of the rotor between a peripheral outlet region and a peripheral inlet region, the divider is formed so that at least some sections of it in planes parallel to the axis deviate from a straight line parallel to the axis. Fig. 1 shows a transverseflow fan comprising a vortex guide 15 separating the inlet region 17 from the outlet region 19, and a cowling 20 extending partially around the rotor 10. To reduce noise due to a compression or suction impulse occurring each time a rotor blade 14 passes the leading edges 18 and 21 of the vortex guide 15 and cowling 20, these edges are inclined or distorted so that the impulse occurring at one point along the length of the blade does not occur simultaneously with those at other points. In this purpose, the leading edges 18 and 21, when viewed in the direction of the arrows A and B respectively, may have a contour comprising one or more helices 32, Fig. 4, four such helices being shown. Instead of helices, shallow circular segments or a sinuous curve similar to a sine curve may be used. The shapes can be inverted. Preferably, the range of angular displacement of points on the contour is at least equal to the angular displacement between adjacent rotor blades.