Patent ID: 6774512
Filing Date: 2004-08-10
Classification: H02K

Abstract:
A claw-pole permanent magnet stepping motor, comprising:a first case unit having a length wherein said first case unit is continuous along its length; a second case unit having a length wherein said second case unit is continuous along its length; said first and said second case units having a total length; a rotor having at least a first and a second permanent magnet; said first and said second case units having a shape supporting said rotor; a third and a fourth arcuate section on each said first and said second case units; a fifth and a sixth side wall section joining each respective said third and forth arcuate sections in a continuous flattened-oval section about said rotor; said third and said forth arcuate sections each having a first diameter; and a ratio of said total length to said first diameter is at least 1:1 a first metal bearing in said first case unit; a second metal bearing in said second case unit; said rotor supported between said first and said second metal bearings; a plurality of magnetic poles on said first and second permanent magnets; a first and a second phase inductor in each respective said first and said second unit case opposite each respective said first and second permanent magnets; said first and said second phase inductors disposed symmetrically in each respective said first and said second case units; and said first and said second phase inductors each formed from at least a first and a second magnetic plate each including multiple claw-poles and a first and a second coil each with a set of connectors, at least one of said claw-poles facing the continuous flattened-oval section of the fifth and sixth side walls whereby said claw-pole permanent magnet stepping motor has a reduced size, eliminates magnetic circuit obstructions, and prevents external flux leakage to allow use with magnetic devices while providing an adequate rotational torque.