Electric motor with optimum core dimensions

A dynamoelectric machine comprising:

• a shell;
• a stator assembly comprising a laminated core having a cylindrical bore therein and being operatively associated with the shell;
• stator winding means operatively positioned relative to the stator core;
• and a rotor comprising a laminated core, said rotor core having a plurality of equally circumferentially spaced semi-closed slots extending radially proximate the outer periphery of the core, the slots defining areas for receiving conducting means therein, wherein the ratio of rotor slot depth to rotor sot opening width is from about 10.8 to about 12.5.

A lamination for use in a generally cylindrical stator core in a dynamoelectric machine having a shell comprising;

• a flat, annular plate of ferromagnetic material comprising a plurality of poles and a yoke extending about the periphery of the plate, said plate having a given outer diameter and a generally circular bore opening having a predetermined inner diameter determined by the distance between oppositely facing poles which extend inwardly from the outer periphery of the lamination;
• a plurality of apertures, positioned in the plate proximate the outer periphery thereof and centered with respect to each pole, for accommodating attachment means;
• means, positioned in the plate, for operatively connecting together a plurality of like laminations to form a stator core;
• and
• wherein the ratio of the stator pole neck minimum width to two times the yoke thickness is from about 0.81 to about 0.91.

A dynamoelectric machine comprising:

• a stator comprising:
• a shell;
• a stator core positioned within and operatively associated with the shell, said stator core comprising a plurality of ferromagnetic stator laminations that collectively define a number of stator poles and a central bore in the stator core;
• stator winding means operatively positioned about each of the stator poles;
• each stator lamination comprising:
• a flat annular plate of ferromagnetic material comprising an annular yoke having a preselected outer diameter, poles extending radially inwardly from the yoke with faces of the poles defining a generally circular bore opening of a predetermined inner diameter, the inner diameter being determined by the distance between diametrically oppositely facing pole faces;
• a plurality of holes operatively positioned in the yoke proximate to the outer periphery thereof, and centered with respect to each pole for receiving attachment means therethrough;
• and
• a rotor comprising:
• a plurality of ferromagnetic rotor laminations, the outer peripheries of which establish a rotor outer diameter, each of the rotor laminations having a plurality of equally circumferentially spaced semi-closed conductor receiving slots, having a preselected depth, extending radially proximate the outer periphery of the laminations, wherein the ratio of the number of slots in the rotor to the rotor outer diameter, in inches, is greater than 14.

A dynamoelectric machine comprising:

• a shell;
• a stator assembly having at least four poles operatively positioned in the shell, the stator assembly comprising a stack of ferromagnetic stator laminations having a plurality of poles that each have generally the same geometric shape, and a cylindrical bore formed therein;
• said stator assembly also having a plurality of sets of stator windings with a stator winding accommodated on each pole;
• each stator lamination comprising:
• a flat annular plate of ferromagnetic material having a predetermined outer diameter and a generally circular bore opening of a preselected inner diameter, the inner diameter being determined by the distance between the opposing poles which extend inwardly from the outer periphery of each lamination;
• at least one connection means for each pole operatively positioned in the plate proximate the outer periphery thereof and centered with respect to each pole for receiving attachment means therethrough;
• a plurality of interlocking means operatively positioned in the plate for interlocking the plurality of laminations together to form a stator core;
• and
• a rotor comprising a plurality of ferromagnetic laminations that form a core, each of the laminations having a plurality of equally circumferentially spaced semi-closed slots extending radially proximate the outer periphery of the lamination, the slots defining areas for receiving at least two conducting means therein, and wherein the ratio of the number of rotor lamination slots to the rotor lamination outer diameter, in inches, is about 15,75.