Brake device for vehicle

A brake device for a vehicle, comprising:

• a housing unit having first and second surfaces respectively facing in mutually opposite directions and respectively having first and second openings with a through-hole extending therebetween;
• a motor unit disposed on the first surface of the housing unit and configured to provide a rotational force;
• a cylinder unit longitudinally extending from within the motor unit into the through-hole of the housing unit, the cylinder unit having a first end portion surrounded by the motor unit and a second end portion protruding outwardly from the second surface of the housing unit via the second opening of the housing unit;
• a bearing unit disposed in the second end portion of the cylinder unit;
• a screw shaft disposed within the cylinder unit and configured to axially rotate in response to receiving the rotational force from the motor unit, the screw shaft having a first coupling portion coupled to the motor unit, a second coupling portion coupled to the bearing unit, and a body portion longitudinally extending between the first and second coupling portions;
• a nut unit coupled to the screw shaft through a ball member and configured to reciprocate in an axial direction of the screw shaft in response to receiving axial rotating of the screw shaft;
• and
• a piston unit coupled to the nut unit and configured to move in conjunction with the nut unit,
• wherein the bearing unit supports an axial load by the piston unit during hydraulic pressure formation of the cylinder unit.