Abstract: There is disclosed a machine for selectively sewing four different kinds of buttonholes, i.e. (1) with an eye, (2) without an eye, (3) with a wedge bar tack, and (4) without a wedge bar tack. The machine accomplishes all of these different types of sewing with the use of only two shaped cams permanently arranged in the machine, the first of such cams being for sewing the eye, and the second of such cams being for sewing the bar tack. The machine has a support plate for the workpiece, such support plate being coupled with one end of a first two-armed lever the second end of which is formed as a pivot of a second two-armed lever whose first end is disengageably connected with the first cam. The second end of the second two-armed lever is disengageably connected with the second cam by way of further members comprising a rod which is rendered immobile in the disengaged position with respect to the overarm of the sewing machine.

Abstract: There is disclosed mechanism for controlling the workpiece pressure grippers of buttonhole bar tacker sewing machines, such machines having means for selectively cutting the buttonhole either before or after the sewing operation. The controlling mechanism comprises a first disengaging member for controlling the pressure grippers, and a second disengaging member for selectively starting and stopping the machine. The two disengaging members are disposed in the path of rotary motion of at least one part coupled in the motion both with the device for driving the workpiece support plate of the machine and with the cam which controls the cutting knife of the machine.