Edge trimmer for sewing machine

摘要

There is an upper lever pivotably supported by an L-shaped arm of a stand positioned on a base or by a bended arm of a stand integral with a holder. One edge of the upper lever is movably fastened to a needle bar of a sewing machine by a needle clamping screw for fastening a needle to the needle bar through a needle clamp body concurrently while the other end thereof is pivotably connected to one of the projected arms of a lower lever through a connecting link. When the upper lever thus constructed oscillates in unison with an up and down motion of the needle bar of the sewing machine, a cutter which is fastened dependingly to the edge of the other projected cylindrical arm of the lower lever shifts up and down with the result that the cutter thereof touches slidably with a shearing edge defined along the front edge of the L-shaped arm portion of the base or a shearing plate fastened to the holder, thereby an edge of cloth materials fed by the feeding device of the sewing machine may be trimmed. The projected cylindrical arm of the lower lever having a cutter at the edge thereof consists of two cylinders one of which is a slidable cylinder provided with a projection of a small diameter which is arranged to fit into or out of a bore of another cylinder by a biasing force curled around the projection of a small diameter whereby the shearing stress between the cutter and the shearing edge may be adjusted.