Electronic parking brake

An electronic parking brake comprising:

• a drum which rotates with a wheel of a vehicle;
• brake shoes installed at two sides in the drum to brake the drum;
• a wheel cylinder configured to push the brake shoes to bring the brake shoes into contact with an inner circumferential surface of the drum;
• and
• an actuator which generates driving power for driving of the wheel cylinder,
• wherein the actuator includes a driving motor which generates the driving power for braking of the drum and a transmission shaft which transmits the driving power of the driving motor to the wheel cylinder, and
• the electronic parking brake further comprises a first helical gear part having a transmission gear provided on the transmission shaft and a driven gear formed on the wheel cylinder and engaged with the transmission gear provided on the transmission shaft, a second helical gear part configured to transmit the driving power of the driving motor to the transmission shaft and the second helical gear part which transmits the driving power transmitted through the transmission shaft to the wheel cylinder,
• a housing is provided outside the actuator;
• and
• wherein the housing includes a first housing surrounding the driving motor and one side of the transmission shaft and a second housing surrounding the wheel cylinder and the other side of the transmission shaft,
• wherein the transmission shaft comprises, a first shaft packaged within the first housing and connected to the driving motor;
• and
• a second shaft packaged within the second housing and connected to the wheel cylinder, wherein the second shaft is fixedly coupled to the first shaft.