The motorised window has a motor whose axle has a drum about which a wire is rolled or unrolled to move the window. The axle has a flange and between this flange and the end of the axle are splines which mate with matching splines on the inner surface of a central hole in the drum. The drum has a number of spring hooks which grip the flange when the drum is placed on the shaft so that it cannot slide axially. The shaft is driven by a gear mating with a worm on the motor shaft.
