Sewing machine with a device for adjusting a pressure applied to a pressure bar and a device for lifting the presser bar

摘要

A sewing machine is disclosed, wherein a downward pressure normally applied to the presser bar may be optionally adjusted in response to a selected pattern of stitches, and further may be reduced when the presser bar is lifted from the lower operative position to the upper inoperative position, and the operation may be performed smoothly and efficiently. More precisely, the sewing machine substantially comprises a presser bar 1 having a presser foot 27 removably mounted to the lower end thereof and being vertically movable with respect to a needle plate by means of a presser bar holder 2 fixedly holding the presser bar 1, a spring 3 for normally giving a downward pressing force to the presser bar and a swingable member 20 which may be swingingly moved around a support pin 20d and has one end 20e operatively connected to the spring 3 and the opposite end 20c pressed against a positioning member 21 which is operated to swingingly move the swingable member 20 to displace the end 20e of thereof with respect to the spring 3 to adjust the pressing force of the spring 3.