Stepping motor
First Claim
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1. A stepping motor comprising:
- a rotor having a plurality of magnetic poles along its circumferential direction;
one stator base arranged near the rotor;
a pair of magnetic yokes fixed on the stator base and arranged to face the magnetic poles of the rotor;
a pair of excitation coils mounted on the pair of magnetic yokes respectively and exciting the pair of magnetic yokes respectively in response to drive pulses which have phase difference; and
a pair of stator magnetic polar portions integrally formed with the stator base, for forming magnetic paths together with the magnetic yokes respectively, wherein, when an angle between the pair of magnetic yokes around a center of the rotor is α
, angles between the pair of magnetic yokes and the stator magnetic polar portions are β
1 and β
2 respectively, and an angle between the pair of stator magnetic polar portions is γ
, and if a number of magnetic poles of the rotor is N, K is an integer, a is an odd number, and b is 0 or 1, each of the angle α and
angles β
1 and β
2 is less than 180° and
obtained from formulas of
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Accused Products
Abstract
A stepping motor including a rotor having a plurality of magnetic poles, one stator base arranged near the rotor, a pair of magnetic yokes fixed on the stator base and arranged to face the magnetic poles of the rotor, a pair of excitation coils for exciting the pair of magnetic yokes respectively in response to drive pulses which have phase difference, and a pair of stator magnetic polar portions integrally formed with the stator base. The stepping motor is constructed to form magnetic paths together with the number of magnetic turns of the excitation coils without increasing the size of the magnetic yokes, thereby enhancing operations and reliability.
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Citations
8 Claims
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1. A stepping motor comprising:
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a rotor having a plurality of magnetic poles along its circumferential direction;
one stator base arranged near the rotor;
a pair of magnetic yokes fixed on the stator base and arranged to face the magnetic poles of the rotor;
a pair of excitation coils mounted on the pair of magnetic yokes respectively and exciting the pair of magnetic yokes respectively in response to drive pulses which have phase difference; and
a pair of stator magnetic polar portions integrally formed with the stator base, for forming magnetic paths together with the magnetic yokes respectively, wherein, when an angle between the pair of magnetic yokes around a center of the rotor is α
, angles between the pair of magnetic yokes and the stator magnetic polar portions are β
1 and β
2 respectively, and an angle between the pair of stator magnetic polar portions is γ
,and if a number of magnetic poles of the rotor is N, K is an integer, a is an odd number, and b is 0 or 1, each of the angle α and
angles β
1 and β
2 is less than 180° and
obtained from formulas of - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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Specification