Patent ID: 6928741

Claim:
A cutting head for rotary trimmers using at least one fixed length of flexible line as a cutting implement comprising: a housing defining an annular wall portion, a perimeter wall portion axially spaced from said annular wall portion and having at least one opening therein, a line support wall adjacent each said opening and extending inwardly therefrom, at least a portion of said wall having a wear resistant surface, a channel extending radially inwardly from each said opening along said support wall for receiving a length of flexible line therein, a post adjacent each said channel proximate said opening in said perimeter wall portion of said housing; a line engagement cam mounted on each said post for pivotal movement about a central axis of said post, each cam being configured so as to be symmetrical about said central axis and defining a plurality of line engaging pointed teeth spaced along an end surface of the cam from an outermost tooth to an innermost tooth such that said teeth generally project from said outermost tooth to said innermost tooth into each said channel at increasing angles of inclination with respect to the wear resistant surface of said support wall and at decreasing distances from said surface; and a spring member operatively connected with each said cam for urging said curvilinear surface on said cam in a first direction toward said opening.