Sewing machine six motion work feeding mechanism

A work feeding mechanism for a sewing machine having a work supporting bed with an axis along its length, a throat plate having a set of mutually orthogonal feed dog accommodating slots defining mutually perpendicular directions of work feeding along the surface of said bed, said directions comprising a longitudinal direction of feeding extending in a direction transverse to the axis along the length of said bed, and a lateral direction of fabric feeding perpendicular to said longitudinal direction, an elongated feed bar carried beneath said bed and extending substantially along the length of said work supporting bed, a feed dog bracket pivotally supported at one extremity of said feed bar including a feed dog having a set of mutually orthogonal work engaging teeth positioned to be accommodated within said feed dog accommodating slots and slidable means for supporting said feed dog on said bracket wherein said feed dog is constrained to slide along a line extending parallel to said axis of said bed,

• gimbal means having a vertical axis pivot, said gimbal means fastened to said feed bar and supporting the extremity of said feed bar opposite the extremity having said feed dog pivotally fastened thereto to permit said feed dog to be driven in said longitudinal direction transversely across said bed and in a direction above and below said throat plate,
• a feed bar drive mechanism operable in timed relation to said sewing machine for imparting oscillations to said feed bar about said gimbal means in mutually perpendicular directions, including said longitudinal direction transversely across said bed to provide work advancing and return movements to said feed dog, and in said direction above and below said throat plate to raise said feed dog to a position above said throat plate during work advancing movement and to drop said feed dog below said throat plate during the return movement thereof,
• means driven by said feed bar drive mechanism for imparting oscillatory motion to said feed dog along said line constrained by said slidable means and extending parallel to said axis of said bed, and
• adjustable control means responsive to electrical signals for varying the amplitude and direction of oscillatory motion imparted to said slidable means by said oscillatory drive means.