Hydraulic unit for brake system

A hydraulic unit comprising:

• a main reservoir tank configured to accommodate a pressurized medium;
• a hydraulic block having a reservoir bore configured to communicate with the main reservoir tank, a cylinder bore in which a master cylinder connected to a brake pedal is provided, a motor bore in which a motor configured to generate liquid pressure by being operated by an electrical signal outputted in response to a displacement of the brake pedal is provided, a hydraulic flow path, and a valve bore in which a valve configured to control a flow of the pressurized medium through the hydraulic flow path is provided;
• and
• an electronic control unit configured to control operations of the motor and the valve on the basis of information on the displacement of the brake pedal,
• wherein the motor bore is provided on a first surface of the hydraulic block,
• wherein a housing of the electronic control unit is provided on a second surface of the hydraulic block that is a surface opposite to the first surface,
• wherein the main reservoir tank comprises:
• a coupling part provided on a third surface that defines a front side surface between the first surface and the second surface;
• an extension part provided in a direction corresponding to a longitudinal direction of the housing;
• and
• a connection part configured to allow the coupling part and the extension part to communicate with each other, and is provided to surround a front side surface of the housing.