GB810909A - Centrifugal blowers - Google Patents

Abstract

810,909. Centrifugal blowers. ELECTROLUX CORPORATION. June 11, 1957 [June 13, 1956], No. 18364/57. Class 110 (1). A centrifugal blower comprises an impeller rotatably mounted in a housing having an axially located outlet and stationary vanes between the impeller periphery and the outlet, each vane being of spiral profile from the outer end through a major portion of its length and changing to a substantially radial profile adjacent the inner end. Fig. 1 shows a blower for a suction cleaner comprising a first stage impeller 22 within a casing 30 and a second stage impeller 24 within a casing 26, the two casings being held together and to the frame 10 of the driving motor by tie-bolts 34. Interstage guide vanes 52, Figs. 1 and 3, are fastened to the front of the casing 26 and to a disc 60 by means of lugs such as 54 which are passed through slots and bent over. Each vane 52 is of spiral form over most of its length, but is bent into the radial direction at its inner end 56 to facilitate the change of the air flow into the axial direction at the inlet to the impeller 24. The cast outlet guide vanes 68 are similarly shaped to facilitate change of air flow into the axial direction. The air cools the motor as it passes through it to discharge openings 74. The impellers 22, 24 comprise spiral vanes secured between side discs by bent-over lugs.