Webbing locking device

Claim 1

A webbing locking device used in a seatbelt system for clamping an intermediate portion of an occupant restraining webbing in a vehicular emergency, comprising: a frame secured to a vehicle body; a lock lever pivotally supported on said frame by a support shaft; lock means for clampingly locking the intermediate portion of the webbing when said lock lever pivots during a vehicular emergency; a first roller rotatably supported on said lock lever, and placed in a position remote from said support shaft, around which the intermediate portion of the webbing is guided, so that said lock lever is pivoted by said first roller when the tension in the webbing increases; supporting means between said lock lever and axially opposite ends of said first roller for rotatably supporting said first roller on said lock lever and enabling said first roller to move in a radial direction with respect to said first roller; contact means for contacting the outer periphery of said first roller only when said first roller moves in said radial direction, to give a frictional resistance to the rotation of said first roller; and the supporting means comprising a first portion secured to the lock lever, a separate second portion secured to the first roller, and resilient biasing means, the first and second portions normally being resiliently urged by the biasing means toward each other into contact so as to maintain the periphery of the roller away from the contacting means, whereupon when the tension in the webbing exceeds a predetermined value the first and second portions are caused to move relative to each other in a direction that brings the periphery of the first roller toward the contacting means,and the first and second portions are caused to move further apart in opposition to the resilient biasing means; whereby, in the vehicular emergency, the tension in a portion of the webbing clamped by said lock means is reduced by said frictional resistance to rotation of said first roller.