Manufacturing method and composite powder metal rotor assembly for circumferential type interior permanent magnet machine

A method of making a powder metal rotor for a circumferential type interior permanent magnet machine, the method comprising:

• filling an inner annular region of a disk-shaped die with a soft ferromagnetic powder metal in solid particulate form;
• filling a plurality of discrete first regions within an outer annular region of the die with a non-ferromagnetic powder metal in solid particulate form so as to leave spaces between each discrete first region;
• filling a plurality of discrete second regions in the outer annular region between the first regions with a soft ferromagnetic powder metal in solid particulate form so as to maintain a radially inner circumferentially extending space between each discrete first region;
• pressing the solid particulate form powders in the die to form a compacted powder metal disk;
• sintering the compacted powder metal disk;
• and
• providing permanent magnets in the radially inner circumferentially extending spaces between the discrete first regions of the outer annular region in an arrangement of alternating polarity to form a composite powder metal disk having an inner annular magnetically conducting segment and an outer annular permanent magnet segment of a plurality of alternating polarity permanent magnets separated by magnetically non-conducting barrier segments and radially embedded by magnetically conducting segments.

A method of making a powder metal rotor for a circumferential type interior permanent magnet machine, the method comprising:

• filling an inner annular region and a plurality of first portions of an outer annular region of a disk-shaped die with a soft ferromagnetic powder metal in solid particulate form,
• pressing and sintering the soft ferromagnetic powder metal in the die to form a compacted and sintered inner annular magnetically conducting segment and a plurality of compacted and sintered outer magnetically conducting segments;
• filling a plurality of second portions in the outer annular region of the die with a non-ferromagnetic powder metal in solid particulate form, the second portions being in alternating relation with the outer magnetically conducting segments;
• pressing the non-ferromagnetic powder metal in the die to form a plurality of compacted magnetically non-conducting barrier segments;
• sintering the compacted magnetically non-conducting barrier segments and the compacted and sintered inner annular and outer magnetically conducting segments;
• and
• providing circumferentially extending permanent magnets in a plurality of radially inner fourth portions in the outer annular region between the magnetically non-conducting barrier segments in an arrangement of alternating polarity to form a composite powder metal disk having an inner annular magnetically conducting segment and an outer annular permanent magnet segment of a plurality of alternating polarity permanent magnets separated by magnetically non-conducting barrier segments and radially embedded by magnetically conducting segments.

A method of making a powder metal rotor for a circumferential type interior permanent magnet machine, the method comprising:

• filling an inner annular region and a plurality of first portions of an outer annular region of a disk-shaped die with a soft ferromagnetic powder metal;
• pressing and sintering the soft ferromagnetic powder metal in the die to form a compacted and sintered inner annular magnetically conducting segment and a plurality of compacted and sintered outer magnetically conducting segments;
• filling a plurality of second portions in the outer annular region of the die with a non-ferromagnetic powder metal, the second portions being in alternating relation with the outer magnetically conducting segments;
• filling a plurality of third portions in the outer annular region of the die with a non-ferromagnetic powder metal, the third portions radially extending through an intermediate portion of each first portion;
• pressing the non-ferromagnetic powder metal in the die to form a plurality of compacted magnetically non-conducting barrier segments and bridge segments;
• sintering the compacted magnetically non-conducting barrier and bridge segments and the compacted and sintered inner annular and outer magnetically conducting segments;
• and
• providing circumferentially extending permanent magnets in a plurality of radially inner fourth portions in the outer annular region between the magnetically non-conducting barrier segments in an arrangement of alternating polarity to form a composite powder metal disk having an inner annular magnetically conducting segment and an outer annular permanent magnet segment of a plurality of alternating polarity permanent magnets separated by magnetically non-conducting barrier segments and radially embedded by magnetically conducting segments with intermediate magnetically non-conducting bridge segments.

A method of making a powder metal rotor for a circumferential type interior permanent magnet machine, the method comprising:

• filling a plurality of discrete first regions within an outer annular region of a disk-shaped die with a non-ferromagnetic powder metal so as to leave spaces between each discrete first region;
• filling a plurality of discrete second regions in the outer annular region between the first regions with a soft ferromagnetic powder metal so as to maintain a radially inner circumferentially extending space between each discrete first region while maintaining a radially extending unfilled region through each discrete second region and filling the radially extending unfilled regions with a non-ferromagnetic powder metal;
• pressing the powders in the die to form a compacted powder metal disk;
• sintering the compacted powder metal disk;
• and
• providing permanent magnets in the radially inner circumferentially extending spaces between the discrete first regions of the outer annular region in an arrangement of alternating polarity to form a composite powder metal disk having a plurality of alternating polarity permanent magnets separated by magnetically non-conducting barrier segments and radially embedded by magnetically conducting segments with intermediate magnetically non-conducting bridge segments.

A method of making a powder metal rotor for a circumferential type interior permanent magnet machine, the method comprising:

• filling an inner annular region of a disk-shaped die with a soft ferromagnetic powder metal;
• filling a plurality of discrete first regions within an outer annular region of the die with a non-ferromagnetic powder metal so as to leave spaces between each discrete first region;
• filling a plurality of discrete second regions in the outer annular region between the first regions with a soft ferromagnetic powder metal so as to maintain a radially inner circumferentially extending space between each discrete first region while maintaining a radially extending unfilled region through each discrete second region and filling the radially extending unfilled regions with a non-ferromagnetic powder metal;
• pressing the powders in the die to form a compacted powder metal disk;
• sintering the compacted powder metal disk;
• and
• providing permanent magnets in the radially inner circumferentially extending spaces between the discrete first regions of the outer annular region in an arrangement of alternating polarity to form a composite powder metal disk having an inner annular magnetically conducting segment and an outer annular permanent magnet segment of a plurality of alternating polarity permanent magnets separated by magnetically non-conducting barrier segments and radially embedded by magnetically conducting segments with intermediate magnetically non-conducting bridge segments.

A method of making a powder metal rotor for a circumferential type interior permanent magnet machine, the method comprising:

• filling an inner annular region of a disk-shaped die with a soft ferromagnetic powder metal;
• filling a portion of the inner annular region in a desired pattern with a non-ferromagnetic powder metal;
• filling a plurality of discrete first regions within an outer annular region of the die with a non-ferromagnetic powder metal so as to leave spaces between each discrete first region;
• filling a plurality of discrete second regions in the outer annular region between the first regions with a soft ferromagnetic powder metal so as to maintain a radially inner circumferentially extending space between each discrete first region;
• pressing the powders in the die to form a compacted powder metal disk;
• sintering the compacted powder metal disk;
• and
• providing permanent magnets in the radially inner circumferentially extending spaces between the discrete first regions of the outer annular region in an arrangement of alternating polarity to form a composite powder metal disk having an inner annular magnetically conducting segment with an inner magnetically non-conducting insert and an outer annular permanent magnet segment of a plurality of alternating polarity permanent magnets separated by magnetically non-conducting barrier segments and radially embedded by magnetically conducting segments.