Electric parking brake control device

An electric parking brake control device that includes:

• lock control means that performs normal lock control for moving a propeller shaft in one direction by causing a motor to rotate in a forward direction, for generating a parking brake force by moving a friction-applying member in connection with movement of the propeller shaft in a direction approaching to a friction applied member mounted on a wheel, and, after generation of the parking brake force, for putting a wheel into a locked state by stopping operation of the motor and by maintaining the parking brake force;
• release control means that performs release control for moving the propeller shaft in an opposite direction to the one direction by causing the motor to rotate in a reverse direction, for reducing a parking brake force by moving the friction-applying member in connection with movement of the propeller shaft in a direction separating from the friction applied member, and, after reduction of the parking brake force, for putting a wheel into a released state by stopping operation of the motor,
• the electric parking brake control device comprising:
• accelerator release control determining means for causing the propeller shaft to be moved to a standby position, which is positioned between a locked position in which the locked state is obtained and a released position in which the released state is obtained, when a vehicle starting operation is performed in the lock control or in the locked state;
• starting state determining means for determining whether a vehicle is in an impossible-to-start state in which a vehicle cannot start travelling after the vehicle starting operation is performed;
• standby cancel release control means for performing the release control to cause the propeller shaft to be moved from the standby position to the released position when the starting state determining means has not determined that the vehicle is in the impossible-to-start state;
• under-impossible-to-start lock control means for performing under-impossible-to-start lock control to generate a parking brake force by moving the propeller shaft in the one direction as a result of the motor being driven and rotated in the forward direction when the starting state determining means determines the vehicle is in the impossible-to-start state;
• and
• non-necessity confirmation determining means for determining whether a non-necessity confirmation state is obtained in which it is unnecessary to perform the under-impossible-to-start lock control, based on whether a state in which a vehicle speed exceeds a specific speed threshold value is maintained for a period of time equal to or longer than a predetermined time threshold value;
• wherein
• the standby cancel release control means causes the release control to be performed to move the propeller shaft from the standby position to the released position when the starting state determining means has not determined that it is impossible to start the vehicle and when the non-necessity confirmation determining means has determined that the non-necessity confirmation state is obtained.