Abstract: An A.C. alternator includes laminated stator core with an tubular frame formed from a plate member which is wrapped tightly about the core and with the opposed end edges of the frame plate welded to the core. The stator laminations having a square perimeter with the corners rounded with a radius of the final core diameter. The corner portion are further provided with a control welding notch and a plurality of circumferentially distributed openings. The laminations are stacked in rotated relation to form the core with a true constant diameter. Each lamination is rotated in the same direction of rotation for 120 degrees relative to the adjacent laminations. The multiple openings in the corner portions are constructed and arranged such that the rotating laminations aligned the similar openings and define a plurality of unobstructed axial cooling passages. The laminations are rotated to establish skewed elongated slots, central notches and air flow openings.

Abstract: A generator exciter for an A.C. sychronous alternator has a rotor secured to the alternator shaft and a compact high power stator. The stator core is a square laminated core. Eight straight sided poles terminate in a concave end defining a circular rotor opening. A first set of four poles is circumferentially spaced to the diametrical four sides of the core. The poles are a minimum length, and of a width approximately equal to twice the depth of the outer square side portions. A second set of four poles are located at the four corners of the core. The second poles are the same width as the first poles but are significantly longer. Each square corner portion significantly enlarges the outer connecting portion and includes a core mounting opening. Precision prewound coils of the same width and of a length slightly less than the pole length are placed on each pole. A generally stepped construction with a slight enlargement between adjacent poles defines recesses of the width of the coils.

Abstract: A permanent magnet generator has a laminated rotor mounted to the driven shaft of a power alternator. The rotor is cylindrical and includes 10 circumferentially distributed elongated axial slots and 10 rotor teeth. Iron-boron-neodymium rare earth magnets are secured within each of the slots, radially and similarly polarized. The magnet and teeth define a consequent 20 pole rotor with a minimum number of magnets. The rare earth magnets are epoxy bonded within each of the corresponding slots. Each slot has a rectangular cross-section with slightly flared sides. The epoxy extends between the recess surfaces and the magnets. The flared sides improve the flux distribution. The outer radial ends of the magnets spaced inwardly of the rotor teeth prevent mechaical damage to the magnets. The outside maximum dimension of the PMG stator is slightly less than the inner diameter of the exciter stator for convenient removal through the bore of the exciter.