Vernier-adjustment means for vacuum sweepers having step-adjustable nozzle height
US4078275A · kind A · utility
Inventor
Key dates
| Filing date | Nov 5, 1976 |
| Grant date | Mar 14, 1978 |
| Priority date | — |
| Expiry date | Nov 5, 1996 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA47L5/34
- WIPO fieldFurniture, games
- WIPO sectorOther fields
Abstract
An upright-type vacuum sweeper has a motor-driven fan in a housing supported by a pair of front wheels on an axle which is vertically adjustable to vary the nozzle height relatively to a floor surface. A ratchet member having two parallel arcuate sets of teeth constitutes in part a lever for effecting the relative movement. A foot-depressible spring-returnable vertically disposed plunger carries a pawl-type escapement element which reciprocates between the sets of teeth to permit stepwise lowering by gravity of the housing and thus the sweeper nozzle. A foot-depressible ratchet-swinging lever provides one-stroke elevation of the housing. Novelly an adjustable screw is positioned to limit downward movement of the housing to provide a vernier adjustment in the low end of the nozzle-adjustment range to facilitate pushing the sweeper, especially over short-nap floor coverings which have been found to produce bothersome frictional resistance to sweeper movement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.