MOTOR

摘要

A motor includes an attachment portion, a first circuit board, and a second circuit board. The attachment portion is fixed to a frame of an apparatus to be driven by the motor. The first circuit board is located axially below coils and axially above the attachment portion. End portions of conducting wires defining the coils are connected to the first circuit board. The second circuit board is located axially below the attachment portion. An AC to DC conversion portion is mounted on the second circuit board. In addition, the attachment portion is arranged between the first and second circuit boards.

主权项

1. A brushless DC motor configured to convert an alternating current to a direct current and to generate a torque with resulting direct current, the motor comprising:
a stationary portion fixed to a frame of an apparatus to be driven by the motor through a support member; and a rotating portion configured to rotate about a central axis extending in a vertical direction relative to the stationary portion; wherein the rotating portion includes:
a shaft extending along the central axis;a rotor holder including a top plate portion extending around the shaft, and a cylindrical wall portion extending axially downward from an outer end portion of the top plate portion; anda magnet fixed to an inner circumferential surface of the wall portion directly or through a yoke; the stationary portion includes:
a bearing portion configured to rotatably support the shaft;a housing including a cylindrical bearing holding portion configured to hold the bearing portion;a plurality of coils arranged in a circumferential direction radially outside the housing and radially inside the magnet;an attachment portion fixed to each of the housing and the support member either directly or indirectly through another member; anda circuit portion electrically connected to the coils; the circuit portion includes:
a plate-shaped first circuit board located axially below the coils and axially above the attachment portion, and to which end portions of conducting wires defining the coils are connected;a plate-shaped second circuit board located axially below the attachment portion, and arranged to have an AC to DC conversion portion mounted thereon; andan electrical connection portion configured to electrically connect the first and second circuit boards to each other; the first circuit board includes a through hole or a cut-out defined therein; the housing extends in the vertical direction through the through hole or the cut-out; the second circuit board includes:
a first region axially aligned with the first circuit board;a second region axially aligned with the through hole or the cut-out; anda third region which does not axially overlap with any of the first circuit board, the through hole, or the cut-out; and the support member is fixed to the third region.