Patent · US Expired

Rotatably driven cutterhead for a vegetation cutting apparatus

US4989321A · kind A · utility

24Cited by
4References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 22, 1990
Grant dateFeb 5, 1991
Priority date
Expiry dateJun 22, 2010

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA01D34/4162
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The invention relates to a rotatably driven cutterhead for a vegetation cutter apparatus. The cutterhead includes a housing in which a spool for the cutting filament is rotatably journalled so as to be rotatable relative to the housing. Switching stops are provided which coact with the spool. Latching levers are pivotally mounted in the housing which each have a latching arm which coacts with the switching stops in dependence upon centrifugal force in such a manner that the spool is first in a latched condition and is then in a freely rotatably condition with correspondingly higher centrifugal force. A predetermined length of filament is unwound in the freely rotatably condition of the spool. The latching arm pivots between an outer release position and an inner latching position and is resiliently biased by a spring in the direction of its latching position. A curved guideway is provided for positively guiding the latching arm out of its outer release position into its inner latching position in which the latching lever coacts with inner latching cams to hold the spool in its latched condition. The curved guideway extends inwardly with respect to the drive axis for positively guid…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.