Patent ID: 9447830
Filing Date: 2016-09-20
CPC Classification: F16D

Claim Text:
1. An electric brake actuator operatively connectable to a vehicle brake to operate the vehicle brake, the electric brake actuator comprising: a first electric motor having a first motor output shaft rotated by operation of the first electric motor to produce a first driving force and a first motor output gear fixed to the first motor output shaft; a second electric motor having a second motor output shaft rotated by operation of the second electric motor to produce a second driving force and a second motor output gear fixed to the second motor output shaft; an actuator output rotatable about an output axis and operatively connectable to the vehicle brake to operate the vehicle brake; and a differential operatively connected to both the first motor output gear and the second motor output gear and the actuator output to transfer the first and second driving forces to the actuator output by way of the differential, wherein an effective gear ratio between the first motor output gear and the actuator output is different from an effective gear ratio between the second motor output gear and the actuator output, the differential comprises a planetary gear set having a sun gear meshed with a plurality of planet gears and a ring gear meshed with the plurality of planet gears, the first motor output gear is operatively connected to a first intermediate gear fixed to the sun gear to transfer the first driving force to the sun gear, and the second motor output gear is operatively connected to a second intermediate gear fixed to the ring gear to transfer the second driving force to the ring gear, an effective gear ratio between the first motor output gear and the first intermediate gear is equal to an effective gear ratio between the second motor output gear and the second intermediate gear, and the electric brake actuator further comprises a first cycloidal speed reducer having a first reducer input rotatable about a first reducer axis and operatively connected to the first motor output gear to receive the first driving force, and a first reducer output rotatable about the first reducer axis and operatively connected to the first intermediate gear to transfer the first driving force to the first intermediate gear; and a second cycloidal speed reducer having a second reducer input rotatable about a second reducer axis and operatively connected to the second motor output gear to receive the second driving force, and a second reducer output rotatable about the second reducer axis and operatively connected to the second intermediate gear to transfer the second driving force to the second intermediate gear.