Patent ID: 6505790
Filing Date: 2003-01-14
Classification: B60R

Abstract:
A pretensioner cooperating with a webbing reel shaft axially extending from a seatbelt retractor webbing reel, that upon activation pretensions seatbelt webbing wound about the reel, the pretensioner comprising:a housing containing a first rectangular passage longitudinally extending within said housing, the passage having a first end and a second end, and, the housing further containing a first end of the webbing reel shaft; a first clutch segment and a second clutch segment fixed and spaced radially outwardly of said first end of said retractor shaft prior to pretensioner activation, each segment in circumferential opposition to the other segment wherein said shaft rotates independently of said segments prior to pretensioner activation and said segments grip said shaft upon pretensioner activation; a geared clutch sleeve fixed radially outwardly of the segments, said sleeve having an inner surface in flush communication with the periphery of said first and second segments wherein said clutch sleeve exerts compressive and rotary torque upon the segments upon pretensioner activation; a geared pulley in geared engagement with said clutch sleeve wherein said pulley exerts a rotary torque upon said clutch sleeve upon pretensioner activation; a strap comprising a first end fixed to said housing, an intermediate portion extending from said first end and across said first passage, and a second end extending from said intermediate portion and spooled about and fixed to said pulley wherein said strap exerts a rotary torque upon said pulley upon pretensioner activation; an actuator positioned within the first end of said passage for tensioning the strap upon pretensioner activation and thereby exerting a torque on the pulley; a gas generant composition, ignitable to activate the pretensioner and release sufficient force to drive the actuator through said second passage; and an initiator contained within said housing and ignitably communicating with said gas generant composition for igniting said gas generant composition, whereby upon ignition of said gas generant and upon linear motion of said actuator, tensioning of the strap is thereby effected, resulting in rotary advancement of the pulley, the clutch sleeve, the segments, the webbing reel shaft, and the webbing reel, thereby winding the reel and tensioning the seatbelt webbing thereon.