Patent ID: 6722299
Filing Date: 2004-04-20
Classification: D05B

Abstract:
A CNC controlled buttonhole sewing machine, comprisinga needle (6), which is drivable via an arm shaft (4); an x-y table (7, 7â€²), which is movable by an x drive (8) in an x direction and by a y drive (9) in a y direction, and which supports a first and a second work piece clamp (17a, 17b, 17â€³b), the first and second work piece clamps (17a, 17b, 17â€³b) being mounted for displacement relative to each other, and which comprises a sliding drive (12, 12â€²) for displacement of the work piece clamps (17a, 17b, 17â€³b) from an initial position of spread by a length of spread d into a final position of spread; and a control unit (32) for control of the drives (8, 9, 12, 12â€²) for displacement of the x-y table (7, 7â€²) prior to the start of production of a buttonhole seam (24), wherein the sliding drive (12) at least of the first work piece clamp (17b, 17â€³b) is an electric positioning motor; andwherein the control unit (32) includes a data storage (33) with data stored therein for displacement of the at least one first work piece clamp (17b, 17â€³b) by a given length of spread d.