Device for flexible line vegetation trimmers and other applications
US6272756A · kind A · utility
Inventors
Key dates
| Filing date | Dec 14, 1999 |
| Grant date | Aug 14, 2001 |
| Priority date | — |
| Expiry date | Dec 14, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA01D34/4161
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A cutting head for a rotary flail retains a coil portion of a cutting line on a spool, and feeds a portion of an excess of the cutting line to the spool to adjust the coil portion and thereby restore a length of the distal portion of the cutting line to maintain a cutting circle of desired size. The distal portion of the cutting line is extended by locating the coil portion such that a centrifugal force arising from rotation of the distal portion overcomes a drag force on the coil portion to unwind a precise amount of the coil portion from the spool. A magazine stores the excess of the cutting line, disposed in a helical path defining a helix having an axis which generally coincides with the axis of the spool. The cutting head has no moving parts, high storage capacity and multiple independent automatic line capability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.