Simplified bump-feed type cutting head assembly for flexible line trimmers
US5020223A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1989 |
| Grant date | Jun 4, 1991 |
| Priority date | — |
| Expiry date | Nov 2, 2009 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01D34/4163
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A compact, light weight, structurally simplified bump-feed type cutting head for a flexible line trimmer is formed from only six components--a hollow cylindrical hub having an open lower end; an annular cover member releasably securable over the lower hub end; a threaded arbor press-fitted into the hub to secure it to the trimmer drive shaft for rotation therewith; a hollow tubular release button member slidably extended through the central cover member opening and axially movable between downwardly extended and upwardly retracted positions; a line storage spool rotatable carried by the release button member within the hub; and a cylindrically coiled compression spring captively retained within the release button and biasing it toward its downwardly extended position. During high speed rotation of the hub about its axis, an outer end portion of flexible line coiled on the spool and passing outwardly through a hub side aperture is whirled through a transverse cutting plane to trim adjacent vegetation. When the outer line end becomes worn away, incremental line feedout is achieved simply by tapping the release button on the ground to activate a line escapement structure defined by co…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.