Patent ID: 6347455
Filing Date: 2002-02-19
Classification: A01D

Abstract:
A head for a string trimmer of the type which receives lengths of string introduced from outside the head, comprising:a base portion; a cover portion removably secured to the base portion to form a trimmer head body having a central axis of rotation; a plurality of spaced openings provided in said head body radially of said central axis for receiving respective lengths of string introduced within the head body from outside said body; a plurality of openings on an upper surface of the cover portion, each being aligned with a respective one of said radially spaced openings; a plurality of slidable members positioned within respective ones of the openings on the upper surface of the cover portion, each slidable member being movable towards and away from the central axis of the head body; a plurality of springs, each associated with a respective one of the slidable members to normally urge the slidable members towards the respective radially spaced openings in the head body; a plurality of pairs of clamping members mounted within the head body, each pair underlying a respective slidable member; a plurality of camming arrangements, each operatively joining a respective slidable member with its associated pair of clamping members and being operative to separate its associated clamping members when the slidable member is moved towards the central axis of rotation of the head body and to allow the clamping members to move towards one another when the slidable member moves towards its respective radially spaced opening in response to force applied to the slidable member by its associated spring, the clamping members being configured to engage respective lengths of string within the head body and to clamp said string with increased force in response to centrifugal force occurring when the head is rotated about said central axis of rotation.