Patent ID: 6597077
Filing Date: 2003-07-22
Classification: H02K

Abstract:
A two-phase step motor of the type having a stator with 4Â·n stator poles, n being a positive integer, four stator coils being wound around said stator poles in a bifilar winding pattern with first and second stator coils wound as a pair around a first group of every other stator pole in alternating clockwise and counterclockwise directions around each successive pole in that group and with third and fourth stator coils wound as a pair around a second group of every other stator pole, different from the first group, the step motor also having a rotor with a permanent magnet sandwiched between two rotor sections, the eight ends of the four stator coils being connected to a two-phase driver providing two sets of pulses in respective phase &agr; and &bgr; that are 90Â° out of phase from each other so as to drive the rotor in steps, wherein the improvement is characterized in that:the first and third stator coils are connected together in series such that current proceeds in both coils in the same sense around the poles of the stators, and the second and fourth stator coils are connected together in series such that current proceeds in these coils in opposite senses around the poles of the stators.