Method relating to a threaded inner sleeve for generator magnet

A method for axially and radially constraining a magnet of a motor or a generator comprising:

• threading an inner sleeve with male threads on an inner sleeve first end and an inner sleeve second end;
• attaching said inner sleeve around at least a portion of a rotor of said motor or said generator;
• threading a first stub shaft and a second stub shaft with female threads matable with said male threads;
• threadably attaching a first stub shaft to an inner sleeve first end;
• threadably attaching a second stub shaft to an inner sleeve second end;
• fitting a magnet against said inner sleeve between said first stub shaft and said second stub shaft;
• shrink fitting an outer sleeve around said magnet, said first stub shaft, and said second stub shaft;
• the outer sleeve having a coefficient of thermal expansion different from that of the inner sleeve whereby the inner and outer sleeves produce increasing radially compressive force on the magnet as a result of an increase in operating temperature of the motor or generator;
• and
• turning at least one of said first stub shaft and said second stub shaft along said male thread of said inner sleeve to axially constrain said magnet by moving said first stub shaft toward said second stub shaft, with said magnet therebetween.

A method for providing a continual compressive force on a magnet during operation of a motor or a generator comprising:

• threading an inner sleeve with male threads on an inner sleeve first end and an inner sleeve second end;
• attaching said inner sleeve around at least a portion of a rotor of said motor or said generator;
• threading a first stub shaft and a second stub shaft with female threads matable with said male threads;
• threadably attaching a first stub shaft to an inner sleeve first end;
• threadably attaching a second stub shaft to an inner sleeve second end;
• fitting a magnet against said inner sleeve between said first stub shaft and said second stub shaft;
• turning at least one of said first stub shaft and said second stub shaft along said male thread of said inner sleeve to axially constrain said magnet by moving said first stub shaft toward said second stub shaft, with said magnet therebetween;
• and
• radially constraining the magnet with a shrink-fitted outer sleeve that has a coefficient of thermal expansion different from that of the inner sleeve so that increase of operating temperature motor or generator produces a corresponding increase in radial force between the outer sleeve and the magnet.