Needle bar operated trimmer

Abstract

A holder (3) for replacing the presser foot of a sewing machine comprising a foot plate (3a) attached to a presser bar (1) of the sewing machine (2), and a presser foot sole (8) operatively associated with the holder and being supported in a pendulating and vertically resilient fashion. A fixed blade (5) is adjustably mounted to the foot plate (3a) of the holder (3). A movable blade (9) is fashioned as a two-armed lever and is pivotably supported in a vertical plane. The movable blade (9) operatively engages the lower arm (13a) of a two-armed intermediate toggle joint with a carrier bolt (13). The other arm (13b) of the toggle joint has a curved cam contour (14). A control pin (15) is guided in the curved path of the cam contour (14), said pin being disposed on a control lever (16) supported (16a) at one end by the holder (3). The other end of the control lever is provided with a fork (6a) at the needle bar (6). The device, mounted as a unit by attaching the holder (3) to the presser bar (1) and by simultaneously attaching the fork (16b) to the cross pin (6b), is ready for operation without any further mounting or adjustment. During the reciprocating motion of the needle bar (6), the scissor-like knife (5, 9) cuts the edge of the length of material conveyed over the foot plate (3a) and underneath the pressure foot sole (8). The thus-cut edge can simultaneously be sewed to prevent raveling.

Dependencies are inferred from the claim text.