Braking system

A braking system that pressurizes a hydraulic fluid in accordance with driver's braking operation to exert a pressure braking force on a vehicle, the braking system comprising:

• a brake pedal that is operated by the driver;
• an operating pressure apply unit that applies an operating pressure to the hydraulic fluid in accordance with driver's operation of the brake pedal;
• a first system that supplies the pressurized hydraulic fluid to a right front wheel cylinder provided for a right front wheel and a left rear wheel cylinder provided for a left rear wheel;
• a second system that supplies the pressurized hydraulic fluid to a left front wheel cylinder provided for a left front wheel and a right rear wheel cylinder provided for a right rear wheel;
• a right-front holding valve that is provided upstream of the right front wheel cylinder within the first system;
• a left-rear holding valve that is provided upstream of the left rear wheel cylinder within the first system;
• a left-front holding valve that is provided upstream of the left front wheel cylinder within the second system;
• a right-rear holding valve that is provided upstream of the right rear wheel cylinder within the second system;
• a first connecting line that connects an upstream side of the right-front holding valve and the left-rear holding valve within the first system to any one of a position between the left-front holding valve and the left front wheel cylinder or a position between the right-rear holding valve and the right rear wheel cylinder;
• a second connecting line that connects an upstream side of the left-front holding valve and the right-rear holding valve within the second system to any one of a position between the left-rear holding valve and the left rear wheel cylinder or a position between the right-front holding valve and the right front wheel cylinder;
• a first changeover valve that is provided in the first connecting line;
• and
• a second changeover valve that is provided in the second connecting line, wherein the first connecting line connects, when the first changeover valve is open, an upstream side of the right-front holding valve and the left-rear holding valve within the first system to a position between the left-front holding valve and the left front wheel cylinder, and the second connecting line connects, when the second changeover valve is open, an upstream side of the left-front holding valve and the right-rear holding valve within the second system to a position between the left-rear holding valve and the left rear wheel cylinder, or
• the first connecting line connects, when the first changeover valve is open, an upstream side of the right-front holding valve and the left-rear holding valve within the first system to a position between the right-rear holding valve and the right-rear wheel cylinder, and the second connecting line connects, when the second changeover valve is open, an upstream side of the left-front holding valve and the right-rear holding valve within the second system to a position between the right-front holding valve and the right-front wheel cylinder.