초록 ▼

A permanent magnet rotor for an electronically commutated motor (ECM) has a core, a plurality of magnetizable elements spaced around the core, and a thin-walled retaining shell which has been stretched around the core and magnetizable elements to hold the elements in position. The rotor is made by a

A permanent magnet rotor for an electronically commutated motor (ECM) has a core, a plurality of magnetizable elements spaced around the core, and a thin-walled retaining shell which has been stretched around the core and magnetizable elements to hold the elements in position. The rotor is made by an inventive method which involves axially aligning the core and surrounding magnetizable elements with the retaining shell, and cold-pressing the retaining shell over the core and elements to sandwich the elements between the shell and core. The core and magnetizable elements serve as a mandrel about which the shell is reformed in a cold working operation. Other aspects of the invention include the fixturing apparatus used to align the core and magnetizable elements with the retaining shell, and apparatus which is used to evenly space the magnetizable elements around the core and hold the elements in position during at least a portion of the cold-pressing operation. Additional features of certain embodiments of the rotor of the present invention include end plates axially disposed adjacent the ends of the rotor core and magnetizable elements, and the use of adhesives between the core and magnetizable elements and/or the ends of the core and magnetizable elements and the end plates.

대표청구항 ▼

A permanently magnetizable rotor having a core, a plurality of magnetizable elements disposed about the core, and a retaining shell having a relatively thin annular wall portion surrounding the core and magnetizable elements, said rotor being produced in accordance with a method comprising the steps

A permanently magnetizable rotor having a core, a plurality of magnetizable elements disposed about the core, and a retaining shell having a relatively thin annular wall portion surrounding the core and magnetizable elements, said rotor being produced in accordance with a method comprising the steps of: a. placing the magnetizable elements around the core and temporarily holding the elements in position; b. axially aligning the core and magnetizable elements with said wall portion of said retaining shell; and c. pressing said wall portion of said retaining shell longitudinally over the core and magnetizable elements so that said wall portion is forced to conform to outer contours of the magnetizable elements as said wall portion moves longitudinally over said elements thereby to permanently retain the magnetizable elements in position around the core.