An intermittent impact type escape device used in high-rise buildings was designed based on escapement principle.The transmission system was composed of a unique designed wirerope antislip mechanism and a reversing gear train.Using the wirerope antislip mechanism,friction between the wirerope and the winding drum was increased effectively to prevent the wirerope relative sliding along the winding drum.The reversing gear train was used to improve rescue efficiency by continually using the device.The control system was used to complete escape wheel periodically “locked to released to rotated to locked” movement,so intermittent movement of main drive chain was realized and personnel could fall intermittently.