Electric Drive Device and Electric Power Steering Device

An electric drive device comprising:

• a motor housing structured to house an electric motor, wherein the motor housing includes an end face part opposite to an output part of a rotating shaft of the electric motor, and wherein the electric motor is structured to drive a controlled object of a mechanical system;
• and
• an electronic control part arranged at the end face part of the motor housing, and configured to drive the electric motor, wherein the electronic control part includes a control circuit part, a power supply circuit part, and a power conversion circuit part;
• wherein
• the end face part of the motor housing includes a power conversion part heat dissipation region and a power supply part heat dissipation region;
• the power conversion circuit part is mounted to the power conversion part heat dissipation region in a manner to allow generated heat of the power conversion circuit part to be transferred to the power conversion part heat dissipation region;
• the power supply circuit part is mounted to the power supply part heat dissipation region in a manner to allow generated heat of the power supply circuit part to be transferred to the power supply part heat dissipation region;
• the electric drive device further comprises a power conversion circuit part holder attached to a portion of the end face part around the rotating shaft;
• and
• the power conversion circuit part holder includes a resilient function member structured to press and hold the power conversion circuit part on the power conversion part heat dissipation region.

An electric power steering device comprising:

• an electric motor structured to apply a steering assist force to a steering shaft, depending on an output from a torque sensor, wherein the torque sensor is structured to sense a direction of rotation of the steering shaft and a rotating torque applied to the steering shaft;
• a motor housing structured to house the electric motor, wherein the motor housing includes an end face part opposite to an output part of a rotating shaft of the electric motor;
• and
• an electronic control part arranged at the end face part of the motor housing, and configured to drive the electric motor, wherein the electronic control part includes a control circuit part, a power supply circuit part, and a power conversion circuit part;
• wherein
• the end face part of the motor housing includes a power conversion part heat dissipation region and a power supply part heat dissipation region;
• the power conversion circuit part is mounted to the power conversion part heat dissipation region in a manner to allow generated heat of the power conversion circuit part to be transferred to the motor housing via the power conversion part heat dissipation region;
• the power supply circuit part is mounted to the power supply part heat dissipation region in a manner to allow generated heat of the power supply circuit part to be transferred to the motor housing via the power supply part heat dissipation region;
• the electric power steering device further comprises a power conversion circuit part holder attached to a portion of the end face part around the rotating shaft;
• and
• the power conversion circuit part holder includes a resilient function member structured to press and hold the power conversion circuit part on the power conversion part heat dissipation region.