Dynamoelectric machine field assembly

摘要

A field assembly for a dynamoelectric machine, particularly for electric engine cranking motors. The field assembly is comprised of a one piece field frame member formed of a high density compacted atomized iron powder. The one piece frame has a generally tubular configuration and has radially inwardly extending pole portions and outer axially extending grooves radially aligned with the pole portions. The frame carries a plurality of field coils which respectively circumscribe the pole portions of the frame. A pole face plate engages each end of a respective pole portion of the frame and a part of each field coil is located between a face plate and an inner wall of the frame. The pole plates are fixed to the frame by parts extending therefrom which pass through openings formed in the frame that extend between the interior of the frame and the outer frame grooves. These parts are headed over in the area of the grooves to secure the pole plates to the frame. The frame, with assembled field coils and pole plates, is press fitted to a tubular outer motor frame and end frames are secured to the main frame by through bolts that extend through the outer grooves of the field frame.