An electric brake device for a vehicle, including: a rotation body that rotates with a wheel; a friction member; and an actuator including (a) a piston configured to come into engagement with the friction member, (b) two electric motors each as a drive source, and (c) a motion converting mechanism configured to convert a rotating motion of each of the two electric motors into an advancing and retracting movement of the piston, the actuator being configured such that the piston is advanced to push the friction member against the rotation body so as to generate a braking force and the piston is retracted to move the friction member away from the rotation body so as to cancel the braking force.

A launch control method for a vehicle may include a step of increasing clutch torque of a clutch according to a decrease in braking pressure, a step of maintaining a current level of the clutch torque for a first reference duration, a step of gradually reducing the clutch torque within a range which is lower than the first reference torque level and is equal to or greater than a second reference torque level which is lower than the first reference torque level, a step of gradually increasing the clutch torque until the clutch torque reaches a third reference torque level which is higher than the first reference torque level, and a step of bringing the control to a stop when a state in which a clutch slip is less than a predetermined critical synchronous slip is maintained for a predetermined critical synchronization duration or longer than the predetermined critical synchronization duration.

A multi-axle drive device and method for operating a multi-axle drive device. The multi-axle drive device is provided with a synchronization clutch present in an operational connection between a first output shaft and a connecting shaft and at least one disconnecting clutch present in an operational connection between the connecting shaft and a second output shaft. The synchronization clutch and the disconnecting clutch are opened in a first operating state and closed in a second operating state. At the same time, with an intended change from the second operating state to the first operating state, the synchronization clutch is maintained at least partially opened and the separation clutch is maintained closed, so that, when a first operating mode is carried out, the disconnecting clutch is opened, and when a second operating mode is carried out, the synchronization clutch is closed again.

Provided is a control device for a four-wheel drive which can maintain driving stability while restraining noise and vibration. A control device includes: a second control device that, when at least one of front wheel has slipped, engages a dog clutch after rotating a propeller shaft by a rotational force transmitted via first and second friction clutches; and a third control device that, if a predetermined condition is satisfied when the front wheels are not slipping, engages the dog clutch after rotating the propeller shaft by the rotational force transmitted via the first and second friction clutches. The time required to synchronize the dog clutch by the third control device is longer than that required to synchronize the dog clutch by the second control device.

A method to control a road vehicle for the execution of a standing start; the control method comprises the steps of: engaging a gear in a transmission while a corresponding clutch is open; progressively closing the clutch causing the clutch to transmit a torque that causes the rotation of at least a pair of drive wheels; determining a target slip of the drive wheels; cyclically determining a real slip of the of the drive wheels; and continuously modulating the torque transmitted by the clutch during the closing of the clutch based of a difference between the target slip of the drive wheels and the real slip of the of the drive wheels.

A launch control method for a vehicle may include a step of increasing clutch torque of a clutch according to a decrease in braking pressure, a step of maintaining a current level of the clutch torque for a first reference duration, a step of gradually reducing the clutch torque within a range which is lower than the first reference torque level and is equal to or greater than a second reference torque level which is lower than the first reference torque level, a step of gradually increasing the clutch torque until the clutch torque reaches a third reference torque level which is higher than the first reference torque level, and a step of bringing the control to a stop when a state in which a clutch slip is less than a predetermined critical synchronous slip is maintained for a predetermined critical synchronization duration or longer than the predetermined critical synchronization duration.

A driving force distribution control device mounted on a four-wheel drive vehicle is provided. A coupling mechanism controller connects a drive shaft with an auxiliary driving wheel and sets a fastening force as a first fastening force, when an increase rate in an accelerator opening becomes more than a given value and a vehicle speed is below a given first speed, and changes the fastening force from the first fastening force to a second fastening force, when a slip of at least one of main driving wheels is detected after the fastening force is set to the first fastening force, and before a given time period has lapsed from the setting of the fastening force, or before the vehicle speed becomes faster than a given second speed. The second fastening force at least immediately after the change of the fastening force is a value larger than the first fastening force.

A drive system for an axle of a motor vehicle comprises at least one drive unit, a drive shaft driven by the drive unit, a first output shaft comprising a first wheel and a second output shaft comprising a second wheel, and a first clutch connecting the drive shaft to the first output shaft, and a second clutch connecting the drive shaft to the second output shaft, and furthermore, a control unit for regulating the clutches. In a stable first driving condition, the clutches are regulated such that a total locking power of the two clutches corresponds at least or substantially to a drive torque generated by the drive shaft; wherein a method comprises at least the following steps: a) determining an unstable second driving condition in which at least one first wheel has a first slip or a second wheel has a second slip; and b) modifying at least one locking ratio of the clutch connected to the at least one slipping wheel, wherein the first clutch has an adjustable first locking ratio and the second clutch has an adjustable second locking ratio.

An electric brake device for a vehicle, including: a rotation body that rotates with a wheel; a friction member; and an actuator including (a) a piston configured to come into engagement with the friction member, (b) two electric motors each as a drive source, and (c) a motion converting mechanism configured to convert a rotating motion of each of the two electric motors into an advancing and retracting movement of the piston, the actuator being configured such that the piston is advanced to push the friction member against the rotation body so as to generate a braking force and the piston is retracted to move the friction member away from the rotation body so as to cancel the braking force.

A method to control a road vehicle for the execution of a standing start; the control method comprises the steps of: engaging a gear in a transmission while a corresponding clutch is open; progressively closing the clutch causing the clutch to transmit a torque that causes the rotation of at least a pair of drive wheels; determining a target slip of the drive wheels; cyclically determining a real slip of the of the drive wheels; and continuously modulating the torque transmitted by the clutch during the closing of the clutch based of a difference between the target slip of the drive wheels and the real slip of the of the drive wheels.