Vehicle brake control apparatus
When an ON operation of an electric parking brake apparatus is performed when a vehicle is moving, a vehicle brake control apparatus executes an EPB stop process in order to stop the vehicle by braking force generated by a hydraulic brake apparatus. If a hydraulic brake malfunction wheel, at which the hydraulic brake apparatus cannot generate braking force properly, is detected during a time period from the beginning of the EPB stop process to the stop of said vehicle, the vehicle brake control apparatus makes the hydraulic brake apparatus stop generating braking force at wheels including the hydraulic brake malfunction wheel. Meanwhile, the vehicle brake control apparatus makes the electric parking brake apparatus start generating braking force at a rear wheel. Subsequently, the vehicle brake control apparatus makes the electric parking brake apparatus start generating braking force to the other rear wheel.
1. A vehicle brake control apparatus applied to a vehicle which is equipped with a hydraulic brake apparatus capable of generating braking force at each of four wheels consisting of a pair of right and left front wheels and a pair of right and left rear wheels and an electric parking brake apparatus capable of generating braking force at each of a pair of said rear wheels, comprising:
an operation switch which is disposed at a position where a driver of said vehicle can reach and with which said driver can perform a predetermined ON operation;
a braking control section configured to control hydraulic braking force and EPB braking force, said hydraulic braking force being generated by said hydraulic brake apparatus, and said EPB braking force being generated by said electric parking brake apparatus; and
an EPB stop process execution section configured to execute an EPB stop process when said ON operation is performed while said vehicle is moving, said EPB stop process being a process to generate a predetermined magnitude of said hydraulic braking force at each of said four wheels, and to generate said EPB braking force at each of a pair of said rear wheels after said vehicle stops moving; wherein
said EPB stop process execution section is configured to start executing a specific brake process when at least one of said four wheels is determined to be a hydraulic brake malfunction wheel during a time period from a time point at which said EPB stop process is started to a time point at which said vehicle stops moving, said specific brake process including a first process executed when said specific brake process is started and a second process executed when a predetermined time period elapses after the first process is started, said first process being a process to start generating said EPB braking force at a preceding brake wheel and to stop generating said hydraulic braking force at one or more of hydraulic brake release wheels including said hydraulic brake malfunction wheel, said second process being a process to start generating said EPB braking force at a succeeding brake wheel, said hydraulic brake malfunction wheel being a wheel at which said hydraulic brake apparatus cannot generate the predetermined magnitude of said hydraulic braking force, said preceding brake wheel being one of a pair of said rear wheels, and said succeeding brake wheel being the other of a pair of said rear wheels.
2. The vehicle brake control apparatus according to claim 1 , wherein
said EPB stop process execution section is configured:
to execute a specific brake wheel selecting process when said EPB stop process execution section starts executing said specific brake process, said specific brake wheel selecting process being a process to select, as a specific brake wheel, one from among said four wheels other than said hydraulic brake malfunction wheel, to select, as said hydraulic brake release wheels, the rest of said four wheels other than said specific brake wheel, and to select, as said preceding brake wheel, one of a pair of said rear wheels opposing to said specific brake wheel in the lateral direction of said vehicle; and
to stop generating said hydraulic braking force at said specific brake wheel when said EPB stop process execution section starts generating said EPB braking force to said succeeding brake wheel.
3. The vehicle brake control apparatus according to claim 2 , wherein
said EPB stop process execution section is configured to select, as said specific brake wheel, one of said front wheels which is not determined to be said hydraulic brake malfunction wheel, if at least one of a pair of said front wheels is not determined to be said hydraulic brake malfunction wheel when executing said specific brake wheel selecting process.
4. The vehicle brake control apparatus according to claim 3 , wherein
said EPB stop process execution section is configured to adjust a magnitude of said hydraulic braking force generated at said specific brake wheel such that said magnitude becomes equal to or smaller than a magnitude of said EPB braking force generated at said preceding brake wheel, when executing said specific brake process.
5. The vehicle brake control apparatus according to claim 2 , wherein
said EPB stop process execution section is configured to adjust a magnitude of said hydraulic braking force generated at said specific brake wheel such that said magnitude becomes equal to or smaller than a magnitude of said EPB braking force generated at said preceding brake wheel, when executing said specific brake process.
6. The vehicle brake control apparatus according to claim 1 , wherein
said EPB stop process execution section is configured to select said four wheels as said hydraulic brake release wheels, if all of said four wheels are determined to be said hydraulic brake malfunction wheels.