GB720082A - Improvements relating to sifters - Google Patents

Abstract

720,082. Securing impellers on shafts. MULLER, A., and MULLER, E. R. Dec. 3, 1951 [May 24, 1950]. No. 12982/50. Class 80 (2). [Also in Groups II and XXX]. In a sifting apparatus comprising a fixed cylindrical sieve 17 and a rotary impeller 29 in which the supply from the hopper 23 is controlled by a rotating, automatically adjustable spreader cone 33 (see Group II) the main driving shaft 26 is reduced at its upper end to be a sliding fit within a sleeve 37 supporting the cone 33 and a plate 27 which carries the impeller is bored to fit the main diameter of the shaft 26 and is provided with a recess to accommodate a circular plate 48. The plate 48 fits over the reduced portion of the shaft 26 and has two diametrically opposed slots 49. A driving pin 50, preferably of square crosssection, passes through the reduced part of the shaft 26 and the slots 49 allow the plate 48 to pass over the pin 50. A driving plate 30 is bolted to the plate 27 and holds the plate 48 in position, a taper pin 51 through the plates 27, 48, 30 preventing relative movement between the plates. The plate 30 has an aperture of the same size as the reduced portion of shaft 26 and has two diametrically opposed quadrants 52 removed to form driving dogs which engage with the pin 50. To place the impeller in its working position the plate 27 is slid on to the upper portion of shaft 26 and rotated until the slots 49 coincide with the pin 50, and the plate 27 then falls downwardly until the plate 48 makes contact with the main part of shaft 27. The plate 27 is then rotated through 90 degrees until the driving pin 50 abuts the sides D of the dogs, and the pin 50 then prevents upward movement of the impeller. The lower end of the sleeve 37 is provided with projections 53, Fig. 12, which rest between the driving pins 50 and faces E of the dogs, and prevent rotation of the impeller relative to the shaft 26 as long as the sleeve is in position.