String trimmer head configuration and method

摘要

A bidirectional trimmer head assembly and the method of configuring the trimmer head assembly. The trimmer head assembly has a housing that attaches to a string trimmer machine. A spool is provided inside the housing. The spool rotates about an axis of rotation. The spool can move longitudinally along the axis of rotation between a first position and a second position. A ratcheting mechanism is provided between the trimmer head housing and the spool. When the spool is in one position, the ratcheting mechanism enables the spool to continuously rotate about the axis of rotation in the direction of or in the direction opposite that in which the trimmer head assembly spins to allow the spool to be fed out or dispensed regardless of the direction of rotation of the trimmer housing. The ratchet mechanism in a second postion prevents the spool from rotating relative to the housing.

主权项

1. A method of configuring a bidirectional trimmer head assembly for use with a trimmer, comprising:
providing a trimmer head housing having an upper end and having a wall defining an interior chamber for receiving a spool; providing said upper end with a lock for rotationally locking the trimmer head housing to a trimmer shaft for rotating 360 degrees about a trimmer central axis of the trimmer head housing and for rotating said bidirectional trimmer head housing in the clockwise direction about the trimmer central axis when said trimmer rotates in said clockwise direction and for rotating said trimmer head housing in the counterclockwise direction about the trimmer central axis when the trimmer shaft rotates in the counterclockwise direction; providing said trimmer head housing with string openings defined therein for admitting trimmer line from the interior chamber to the area outside of the trimmer head housing; providing said spool with a hub formed about a spool central axis of the spool and with a top flange that radially extends from said hub in a first plane that is perpendicular to said spool central axis, said spool being configured to rotate selectively in both said clockwise and counterclockwise direction about said spool central axis independent of said trimmer head housing rotation direction when said spool is not in interfering alignment with the trimmer housing; providing said trimmer head assembly with a bidirectional ratchet mechanism between said trimmer head housing and said spool, said ratchet mechanism comprising a top flange on said spool having a plurality of spaced cog projections that extend therefrom, and a plurality of ramp projections on said cylindrical housing that extend into said interior chamber of said trimmer head housing; biasing said spool into a first spool axial position spaced apart axially from said trimmer upper end wherein said cogs and said ramps are axially aligned within the interior chamber such that rotation of said spool relative to the trimmer head housing in a first direction within said interior chamber to a first rotation position causes at least one of said cogs to strike at least one of said ramps preventing further rotation of the spool relative to the trimmer head housing in the first direction, and wherein rotation of said spool relative to the trimmer head housing in a second direction opposite said first direction within said interior chamber to a second rotation position causes at least one of said cogs to strike at least one of said ramps preventing further rotation of the spool relative to the trimmer head housing in the second direction of the spool relative to the trimmer head housing when said spool is in said first spool axial position.