portions 70 the patch pocket p whose upper edge is folded is positioned on the putting surface 24l so that the upper edge touches the positioning surface 24a of the gage plate 24 the patch pocket p thus positioned on the gage plate 24 is folded by a process to be explained below and is overlapped on the cloth w in the invention a hollow 50 is provided on the machine table 14 to be faced to the double folded portion 80 the hollow 50 has a depth capable of holding the double folded portion 80 with the gage plate 24 when the folded portion 70 is held between the gage plate 24 and the machine table 14 the depth of the hollow 50 is adjustable in order to hold any double folded portions regardless of their varied thickness the adjustability is provided by a movable hollow bottom plate that may be moved upwardly or downwardly by means such as a screw adjustment or a cam not shown the hollow 50 has a width and a length capable of not exposing the double folded portion 80 when the double folded portion 80 is held between the gage plate 24 and the hollow 50 further the hollow 50 has an inclined guide portion 53 at the side of the sewing machine 11 so that the bottom surface of the hollow 50 slopes upwardly towards the surface of the machine table 14 further a stopper 100 which extends in the x direction is fixed by screws 110 to the bottom surface of the hollow 50 so that the upper surface of this stopper 100 lies in the same plane as the machine.