A stitcher comprises a main frame (1) which can perform jump-stitching operation. A jump-stitching hole (3) and a groove (4) for holding ribs of an umbrella are provided on the main frame . A clutch is provided between a motor (5) and a transmission mechanism in the main frame (1) . A clutch control lever (6) for controlling the clutch is controlled by an electromagnet (7) .The electromagnet is connected in series with a time relay (8) , an dot operated-switch (9) and a power supply . A production line can be built in such a manner that several stitchers can be arranged in turn , and the different needle boards are provided for the respective stitcher based on the product technological requirements . The advantages of the stitcher are high production efficiency , high product quality and low cost.