Vacuum cleaning with powered brush roll
US4847944A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 30, 1988 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Sep 30, 2008 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA47L9/0455
- WIPO fieldFurniture, games
- WIPO sectorOther fields
Abstract
A vacuum cleaner having a powered brush roll with a one-piece thread guard and mounting portion. The thread guard is a molded thermoplastic element which encloses the adjacent end of the brush roll and the bearing mounted in such adjacent end. The thread guard provides a skirt extending around the adjacent end of the brush roll and is held against rotation with the brush roll by a mounting portion. The mounting portion of the thread guard provides a sound-deadening mounting structure for the brush roll. The skirt is initially sized to frictionally fit the adjacent end of the brush roll and, after initial relative rotation between the skirt and the brush roll, provides a zero clearance fit to prevent string, thread and other debris from entering the bearing zone. During initial operation, the heat softens the thermoplastic material of the skirt, causing it to wear away and deform until frictional contact is eliminated and a free running condition occurs. The frictional contact is eliminated when a zero clearance fit is provided. The brush roll body is wood, which tends to change dimensionally with changes in ambient humidity. If the brush roll body expands slightly during the use of…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.