Load sensing device for electric brake

An actuator for an electric brake of a vehicle having a caliper assembly driven by a motor, comprising:

• a gear train for transferring torque from the motor to the caliper assembly to brake the vehicle, the gear train including an input gear and a sun gear having a slip-fit connection with one another;
• a load sensing device for sensing relative rotation between the sun gear and the input gear in response to rotation of the motor during a braking operation, comprising:
• a torsion spring having a base rotatable with the sun gear and arms fixed to the input gear;
• and
• a magnetic position sensor aligned with the torsion spring for detecting deflection thereof indicative of the relative rotation;
• and
• a controller connected to the load sensing device and configured to adjust the torque applied to the gear train in response to receiving signals from the load sensing device indicative of the relative rotation.

A method of controlling a caliper assembly of a vehicle, comprising the steps of:

• applying current to a motor for actuating the caliper assembly to initiate a braking operation;
• monitoring relative rotation between a sun gear and an input gear in a gear train as torque is generated from the motor to a spindle, monitoring the relative rotation including:
• determining rotation of a first magnetic position sensor rotatable with the sun gear;
• determining rotation of a second magnetic position sensor rotatable with the motor;
• and
• comparing the determined rotations to one another to monitor relative rotation between the sun gear and the input gear;
• and
• adjusting the current applied to the motor until the monitored relative rotation reaches a predetermined amount.