Patent ID: 6901667
Filing Date: 2005-06-07
Classification: A01D

Abstract:
1. A trimmer head for use in flexible line rotary trimmers of the type adapted to be bumped against the ground to effect the feeding of predetermined lengths of line, said head comprising: a housing circumscribing an interior area and defining an open-ended tubular member extending axially into said area, said tubular member defining an upper portion non-circular in cross-section and a lower portion non-circular in cross-section; a drive bolt for securing said head to the trimmer and defining a head portion and a shaft portion, said head portion being disposed within said upper portion of said tubular member and shaped so as to create an interference fit therewith, said shaft portion projecting from said head portion through said lower portion of said tubular member in said housing; a spool assembly having a common axis of rotation with said housing and defining a cylindrical body portion, a cutting line storage area disposed about said body portion and a bumper for engagement with the ground; a line feeding assembly to provide outward feeding of predetermined lengths of line in response to the striking of said bumper on the ground, said line feeding assembly including a cam member having an upper head portion disposed within said lower portion of said tubular member and shaped so as to create an interference fit therewith and a pair of vertically adjacent, similarly shaped and rotationally offset first and second cams disposed below said upper head portion of said cam member, and a cam follower releasably connected to said spool assembly and defining a plurality of engagement surfaces adapted to selectively engage said cams in predetermined rotational increments in response to the striking of said bumper on the ground, whereby relative rotation is produced between said housing and said spool assembly; and a retainer carried by said shaft portion of said drive bolt adjacent said cam member for securing said cam member and said cam follower to said shaft portion of said drive bolt.