Motor, turbocharger and assembly method turbocharger

A motor comprising:

• a housing that is cylindrical;
• a stator located inside the housing;
• and
• a motor rotor that rotates inside the stator, wherein
• the housing comprises an inner peripheral surface including:
• a first inner peripheral surface formed over a predetermined length from a first end side of the housing toward a second end side of the housing so as to have a constant inner diameter;
• and
• a second inner peripheral surface formed at a portion near the second end of the housing with respect to the first inner peripheral surface,
• a first stator fixing section which fixes the stator is formed in the first inner peripheral surface of the housing,
• a second stator fixing section which has a smaller inner diameter than the first stator fixing section is formed at a position spaced from the first stator fixing section in the axial direction of the housing, in the second inner peripheral surface of the housing
• the stator includes:
• a stator body having a core wound around a coil;
• and
• a stator case storing the stator body,
• the stator case has an end formed with a flange section protruding toward an outer peripheral side,
• the stator case has an outer peripheral surface including:
• a first outer peripheral surface formed over a predetermined length shorter than the first inner peripheral surface of the housing from a side close to the flange section so as to have a constant outer diameter;
• and
• a second outer peripheral surface formed so as to have an outer diameter smaller than the first outer peripheral surface,
• a first fixed section fitted to the first stator fixing section of the housing is formed in the first outer peripheral surface of the stator case,
• a second fixed section which has a smaller outer diameter than the first fixed section and which is fitted to the second stator fixing section of the housing is formed at a position spaced from the first fixed section in the axial direction of the stator, in the second outer peripheral surface of the stator case,
• an entire length in a longitudinal direction of the first outer peripheral surface of the stator case radially faces to be fitted to the first inner peripheral surface of the housing,
• the housing further comprises a radially contracted surface which is between the first inner peripheral surface and the second inner peripheral surface, and which is formed in a tapered shape such that an inner diameter of the radially contracted surface gradually reduces from the first inner peripheral surface toward the second inner peripheral surface,
• the stator case further comprises a radially contracted surface which is formed between the first outer peripheral surface and the second outer peripheral surface, and which is formed in a tapered shape such that an outer diameter of the radially contracted surface gradually reduces from the first outer peripheral surface toward the second outer peripheral surface,
• between a first fitting section, which is comprised of the first stator fixing section and the first fixed section, and a second fitting section, which is comprised of the second stator fixing section and the second fixed section, a large clearance section having a larger clearance between the inner peripheral surface of the housing and the outer peripheral surface of the stator than the first fitting section and the second fitting section is formed, the large clearance section being a space which is surrounded by the first outer peripheral surface of the housing, the radially contracted surface of the housing, the second outer peripheral surface of the stator case, and the radially contracted surface of the stator case.