GB584825A - Improvements in or relating to suction cleaners - Google Patents

Abstract

584,825. Vacuum cleaners. HOOVER, Ltd. Jan. 25, 1945, Nos. 2010 and 2011. Convention dates, Jan. 28, 1944, and March 23, 1944. [Classes 8 (i) and 8 (ii)] In a suction cleaner comprising an initial dust separator 15 shown as a whirl chamber and a final separator or filter 57 cleaned by a nozzle 66 which receives its suction from the initial separator and delivers the collected dust thereto during a filter-cleaning period, the motor has two rotating parts, e.g., the rotor and stator one of which drives the fan 19 and the other drives the filter-cleaning nozzle. The motor shaft is supported by a bearing 38 in a double wall 13 separating the fan and motor, and a second bearing 39 on the motor frame casing 41 which is rotatably carried by a bearing structure 47 on the wall 13; current is supplied through a switch 53. Air which has passed through the filter flows out through ports 61 in a second wall 14 and an exhaust port 62 in the cover to which port a blowing tool can be connected. The casing 41 is supported at its rear end by the conduit 67 of the filter nozzle, rotatable in a bearing, and its rate of rotation is slowed down by a gear 77 engaging a gear 78 on a shaft which through linkage is caused to oscillate a vane, having a small aperture, within a casing 89 containing air or liquid, and constituting a dashpot. Normally rotation is prevented by a pin engaging the gear 77, but when by the rise of pressure within the filter a diaphragm is actuated, it releases this pin, and at the same time opens a valve 74 to connect the nozzle with the conduit 73 leading to the first separator 15. The release of the pin allows rotation of the stator and the initial movement is caused to release a spring switch to increase the motor speed by cutting out a part of the field winding. In another form, reduction gear is provided between the frame 41 and the filter nozzle. In a third form, current is conveyed to the rotatable stator by coil springs attached to the stator and to fixed terminals, and in normal operation the springs hold the stator against rotation. When the diaphragm within the filter is moved by rise of pressure due to clogging of filter, it operates a switch to move the' motor connections to high-speed position in which the stator is rotated winding the springs, the switch being returned to low-speed position by a pin on a rotary part controlling a solenoid circuit to limit the cleaning movement to a single complete rotation. A piston dashpot contrcls the speed of the filter cleaning nozzle.