GB571584A - Improvements in or relating to suction cleaners - Google Patents

Abstract

571,584. Suction cleaners. HOOVER, Ltd. Feb. 25, 1944, No. 3511. Convention date, April 26, 1943. [Classes 8 (i) and 8 (ii)] In a fan suction cleaner of the type comprising a preliminary separator or whirling chamber 12, Fig. 1, a final separating chamber 31 containing a filter bag 32, and a filter cleaning nozzle which returns dirt to the preliminary chamber or inlet port, the filter cleaning nozzle is caused to move over the filter in response to movement of casing or main cleaning nozzle. Step by step rotation of the filter cleaning nozzle is effected by pawl and ratchet 74, 58. The ratchet is fixed to the bushing of the nozzle arm 47 and the pawl is carried by a bell-crank lever 71 pivotally mounted on a bracket 72 on an inner casing wall 54. The upper arm of the lever is bracketed to lower plate 66 of bellows 61 connected by conduit 67 to the main inlet 23.,; where pressure changes cause the lower bellows plate to reciprocate and the filter cleaning nozzle to rotate. Such pressure changes are induced by a rocking plate 76 pivotally,.mounted in the main nozzle 10 admitting additional air on each reversal of direction of movement of the main nozzle. In a modification, Figs. 8 and 9, the ratchet 58 is rotated by a spring loaded pawl 86 carried by a spring controlled armature 82 of a solenoid 81 energised by a bob-weight operated switch located between the outer casing 1 and the preliminary separator 12 and actuated by movement of the cleaner.