Abstract: A sewing machine includes, and can have attached thereto, a synchronizing apparatus by which a presser foot bar and a feed foot bar, and the respectively connected presser foot and feed foot, are lifted and lowered in synchronization with the vertical reciprocation of a needle bar to which a stitching needle is connected. A lift body is pivoted to both the presser foot bar and the feed foot bar. The lift body has an arcuate surface against which a roller connected to the needle bar acts to pivot the lift body alternately about the two connections. This provides appropriate lifting and lowering of the presser foot bar and the lift foot bar during a stitching cycle.

Abstract: A sewing machine drive assembly having one or more pulleys and drive belts also includes a mechanism for enhancing traction between a belt and a pulley to resist slippage under maximum power to be coupled through the drive assembly from a motor to the crankshaft of the sewing machine. The traction enhancing mechanism includes a support member and belt engagement members connected to the support member at respective locations so that the belt mounted on the pulley with which the mechanism is associated is deflected inwardly.

Abstract: An apparatus is disclosed which is to be connected to a domestic sewing machine for converting it into one capable of sewing heavier materials and sewing materials having edgewise designs so that the designs are maintained in alignment. The converted machine can also be capable of having an adjustable amount of hook throw. This apparatus includes a member which pivotally connects a needle bar and a feed foot to the sewing machine. The apparatus also includes a member which pivots the connecting member back and forth in a feed direction and a reverse feed direction. So that the workpiece being sewn by the machine will not slip during pivoting in the reverse feed direction, the apparatus also includes a clamp element for retaining the workpiece against a workpiece supporting surface during this time. Additionally the apparatus includes a mechanism which lowers and raises a feed dog when the connecting member has been pivoted to the substantial extremes of the feed direction and reverse-feed direction.

Abstract: An apparatus for limiting the displacement of a presser bar reciprocatingly mounted in a frame of a sewing machine is disclosed to include a contact member for contacting the presser bar after the presser bar has moved a predetermined distance. The apparatus further includes a latch member, having the contact member associating therewith, for releasably engaging the frame of the sewing machine so that the contact member is prevented from moving in the same direction as the presser bar. So that the latch member may be disengaged from the frame, the present invention also includes a mechanism for decoupling the latch member. The apparatus further includes a mechanism for positioning the latch member so that different portions of the contact member overlie the path of movement of the presser bar during different portions of a stitching cycle.

Abstract: An apparatus is disclosed which is to be connected to a domestic sewing machine for converting it into one capable of sewing heavier materials and sewing materials having edgewise designs so that the designs are maintained in alignment. The converted machine can also be capable of having an adjustable amount of hook throw. This apparatus includes a member which pivotally connects a needle bar and a feed foot to the sewing machine. The apparatus also includes a member which pivots the connecting member back and forth in a feed direction and a reverse feed direction. So that the workpiece being sewn by the machine will not slip during pivoting in the reverse feed direction, the apparatus also includes a clamp element for retaining the workpiece against a workpiece supporting surface during this time. Additionally the apparatus includes a mechanism which lowers and raises a feed dog when the connecting member has been pivoted to the substantial extremes of the feed direction and reverse-feed direction.

Abstract: The present invention is directed to apparatus for attachment to a conventional sewing machine to convert the sewing machine to one having a top and bottom workpiece feed mechanism whereby workpieces of extra thickness can be fed through the mechanism and stitched by the machine. The apparatus of the present invention includes a frame adapted to be attached to a side of the sewing machine, a vertically positioned tubular member pivotally attached to the forward end of the frame so that the member is free to move horizontally but not vertically, a feed foot bar telescopically mounted within the tubular member so that the feed foot bar is free to move vertically and is moved horizontally with the movement of the tubular member, and a feed foot attached to the feed foot bar positioned above the sewing machine work supporting surface adjacent the sewing machine feed dog disposed therein.