A vehicle brake control device, comprising:
- a vacuum booster which assists operation force inputted to a brake operating member in accordance with differential pressure between a negative pressure chamber and a variable pressure chamber when the brake operating member is operated;
- a master cylinder in which hydraulic pressure corresponding to the operation force assisted by the vacuum booster is generated;
- a wheel cylinder provided for a wheel in which inner hydraulic pressure increases as the hydraulic pressure in the master cylinder increases;
- and
- a brake adjusting mechanism configured to adjust the hydraulic pressure in the wheel cylinder even when the brake operating member is not operated,
- wherein
- the vehicle brake control device is applied to a vehicle in which brake force applied to the vehicle is increased by an increase in hydraulic pressure in the wheel cylinder,
- the vehicle brake control device further comprising:
- an assistance control unit which performs brake assistance processing of increasing the hydraulic pressure in the wheel cylinder by a target increase amount based on assistance limit pressure by allowing the brake adjusting mechanism to operate when the vacuum booster reaches assistance limit in a situation in which the brake operating member is operated;
- and
- a target increase amount setting unit which, when determining that emergency braking is requested from an operation mode of the brake operating member, makes the hydraulic pressure in the master cylinder at that point in time the assistance limit pressure and sets the target increase amount based on the assistance limit pressure,
- the assistance control unit performs the brake assistance processing when it is determined that the emergency braking is requested,
- wherein
- the vehicle brake control device is configured such that, in a case where the hydraulic pressure in the master cylinder at a point in time when the vacuum booster reaches the assistance limit predicted from the negative pressure in the negative pressure chamber is made negative pressure conversion hydraulic pressure, the negative pressure conversion hydraulic pressure increases as the negative pressure in the negative pressure chamber is higher,
- the vehicle brake control device comprising:
- a target hydraulic pressure setting unit which increases target hydraulic pressure as a difference obtained by subtracting the assistance limit pressure from the negative pressure conversion hydraulic pressure at a point in time when it is determined that the emergency braking is requested is larger,
- wherein
- the target increase amount setting unit makes a difference obtained by subtracting the hydraulic pressure in the master cylinder from target hydraulic pressure set by the target increase amount setting unit the target increase amount, and
- the target hydraulic pressure setting unit corrects to decrease the target hydraulic pressure when the negative pressure in the negative pressure chamber increases in a situation in which the brake assistance processing is performed.