GB884218A - Improvements in and relating to radial flow fans - Google Patents

Abstract

884,218. Centrifugal fans. SELBACH, A., AMME, P., and AMME, W., [trading as POLLRICH & CO., PAUL]. June 3, 1959 [June 14, 1958], No. 18930/59. Class 110 (1). In a radial flow fan with a rotatably adjustable spiral casing, a peripheral wall of the casing rests on the base frame of the fan in every position of adjustment. In Fig. 1 a fan casing 1 with a spirally curved wall 3 and an outlet 2 lies partly in a recess of a base frame formed by two transverse section members 5, 6 and two longitudinal section members 7. The easing is supported by the members 5, 6 and is secured to the base frame by releasable clamping members 10 acting on outwardly projecting edges 4 of the casing. All positions of the outlet 2 can be obtained by rotating the peripheral wall on the edges of the members 5, 6. The " lower horizontal " position of the outlet (Fig. 5) is effected since the section member 6 has a smaller height than member 5, and after reversal of the base frame the support edge of member 6 is in a lower position. Intermediate " downwardly inclined " positions of the outlet (Fig. 6) are obtained by removing member 6 and replacing it by support brackets 11 adjustably mounted on the two side walls of the casing and secured to the base frame by the clamping members 10. The " vertically downward " position of the outlet is achieved by securing the rim of outlet 2 to the section members 5, 6 by a frame on the outlet. In Fig. 10 each side wall 9 of the casing is reinforced on the inside by a respective coaxial ring 9<SP>1</SP>, 9<SP>11</SP> of which the one peripheral edge is connected, to the casing side wall directly and the other edge to the casing side wall through the intermediary of a spiral-shaped sheet metal cone 9<SP>111</SP>. The driving motor 17 is secured to two section members 18 which are displaceable on the longitudinal section members 7 so that the tension of the driving belt may be adjusted to suit the varying position of the casing. In the case of fans with large output (Fig. 11) the rotational forces of the rotor are not transmitted through the casing but through a pedestal 19 supporting the bearing means 13 of the fan shaft and secured, independently of the casing, to the base frame, which is extended in the axial direction. The pedestal is displaceable on the base frame transversely the fan axis, and the walls of the pedestal, which carry the displaceable fan bearing 13 and the fan driving motor 17, are inclined to one another in such a manner that in both extreme positions adjustment of the bearing 13, the distance between the motor axis and the fan bearing axis is the same.