Thread cutter for button sewing machine, has control mechanism that moves movable knife so that sliding contact of movable knife with stationary knife is enabled when air cylinder makes knife mechanism to swing forward

摘要

An air cylinder (22) makes the knife mechanism to reciprocate between the lower and lateral positions. A control mechanism for opening/closing pivot of the movable knife (14) moves the movable knife in one direction about the axis of rotation, so that the sliding contact of movable knife and stationary knife (16) is enabled when air cylinder causes the knife mechanism to swing forward. The movable knife is moved in another direction to avoid sliding contact with stationary blade when the knife mechanism is made to swing back by air cylinder.