A printing device having a detachable printwheel coupling means which includes a motor driven drive plate which is formed with a cantilevered spring finger and an aligning slot disposed on the side opposite the spring finger. The spring finger carries at its free end an alignment pin which automatically engages a radially offset cam surface located in a recess formed in the hub of a printwheel when the drive plate rotates relative to the printwheel. The printwheel hub also includes a drive pin which engages the aligning slot when the printwheel and drive plate abut under the urging of a pressure plate. The device inhibits angular and radial movement between the drive plate and the printwheel.