| 摘要 |
748,574. Suction cleaners. HOOVER, Ltd. Oct. 16, 1953 [Oct. 17, 1952], No. 28572/52. Class 8(1). Nozzle height adjusting means for a vacuum cleaner of the handle propelled type in which wheels 11 are mounted on the ends 24 of a cranked shaft 25 and one end 24 rests on a cam 28 having a number of depressions 31 at varying radial distances from the axis of rotation 29, comprises a ratchet 41 secured to the cam 28 and a pawl 40 fixed to a spring 35 secured to the housing at one end and carrying a pedal 37 at the other. Depressing the pedal 37 stresses the spring 35 and causes the pawl 40 to engage the next tooth on the ratchet 41. On releasing the pedal the spring 35 rotates the ratchet and cam and the end 24 engages another of the depressions 31. In a modification the spring 35 is replaced by a coil spring which carries a hook which engages a face ratchet formed on the cam. |
