Patent · US Expired

Bump-feed trimmer

US4419822A · kind A · utility

26Cited by
4References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 12, 1982
Grant dateDec 13, 1983
Priority date
Expiry dateJan 12, 2002

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA01D34/4163
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A bump-feed monofilament string trimmer has a sleeve-like escapement member (52) axially slidable on a drive member (42) and nested in a spool member (66) which holds a coil (71) of cutting filament. Axially downwardly extending fingers (84) of the escapement member (52) engage in window-like slots (92) in a downwardly extending dome-like protrusion (16) of the spool member (66) to prevent relative rotation between the two members (52,66). The fingers (84) have external screw threaded portions (86) which extend through the slots (92) and are engaged by a nut (18) which releasably secures the spool member (66) to the escapement member (52). The driving member has teeth (88) which normally drivingly engage with an upper series of internal clutch teeth (58) of the escapement member, and temporarily engage with a lower series of clutch teeth (102, 104) when the dome-like protrusion (16) is "bumped" on the ground, whereby discrete lengths of cutting filament are let out from the spool member (66).

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