Brake apparatus for vehicle

A brake apparatus for a vehicle, comprising:

• a drive unit configured to generate a rotational force in a first rotational direction or a second rotational direction opposite to the first rotational direction;
• a piston unit configured to move forward or backward in response to receiving the rotational force from the drive unit;
• a transfer gear unit configured to transfer, to the piston unit, the rotational force from the drive unit;
• a parking gear unit configured to rotate along with the transfer gear unit, the parking gear unit including a parking protrusion;
• a locking unit facing the parking gear unit and including a parking drive unit and a locking member, the parking drive unit being configured to move the locking member into engagement with the parking protrusions of the parking gear unit to limit a rotation of the parking gear unit;
• and
• an unlocking unit configured to enable the locking member of the locking unit to be moved apart from the parking protrusion of the parking gear unit in response to the rotational force being generated in the second rotational direction from the drive unit,
• wherein:
• the parking drive unit is configured to slidably move in a direction parallel to the reciprocal axis of the locking rod, and
• the unlocking unit is connected to the parking drive unit and configured to longitudinally expand or contract to selectively press the parking drive unit toward the parking gear unit.