Patent ID: 9253942
Filing Date: 2016-02-09
CPC Classification: A01D

Claim Text:
1. A trimmer head assembly, comprising: a housing having a base and a peripheral wall that extends from said base, wherein said housing defines an interior, and wherein string line openings are disposed in said peripheral wall; a spool positioned within said interior of said housing, said spool having a top flange and a bottom flange; a cam guide formation disposed atop said top flange of said spool, wherein said cam guide formation has pathway walls defining a pathway; a cam arm mounted to said housing at a pivot connection, said cam arm having a cam projection extending therefrom that extends into said pathway of said cam guide formation; and a spring for biasing said cam arm about said pivot connection and into a first orientation, pathway walls include a plurality of ramps, each of said ramps extends from a first ramp end to a radially outward second ramp and said ramp, wherein when said trimmer head housing is rotated in a first direction relative to said cam arm pivot connection, said cam projection follows along a first of said plurality of ramps from said ramp first end to said second ramp end causing said spring to compress and further rotation causes said cam projection to move from said first of said plurality of ramps to a second of said plurality of ramps; and wherein when said trimmer head housing is rotated opposite said first direction relative to said cam arm pivot connection, said cam projection follows along a first of said plurality of ramps from said ramp second end to said first ramp end causing said spring to expand and further rotation causes said cam projection to rest between at said first of said plurality of ramps and a second end of a second of said plurality of ramps, whereby the spring bias of said spring on said cam projection prevents said cam projection from rotating further in said direction opposite said first direction relative to said first of said plurality of ramps; and further including a second cam guide formation disposed on said bottom flange of said spool.