Methods, apparatus, systems and articles of manufacture are disclosed for automatic calibration of electronic trailer brake gain. An example apparatus includes a trailer brake gain calibration module programmed to compare a calculated trailer brake torque to at least one of a first or second threshold, adjust a gain value based upon satisfaction of at least one of the first or second threshold, and apply a pressure to a trailer brake based on the gain value.

A overrun brake system includes a gas spring with a gas-tight cylinder and a piston with holes allowing gas to slip through so that the pressure is the same on both sides. Since the free end of the piston has a larger area than the side where the piston rod is located, the gas spring will act as a compression spring. To prevent the overrun brakes from being activated during reversing, the gas spring has a solenoid controlled valve receiving current from the reverse light circuit and closing the flow of gas through the piston when the towing unit's gear is set into reverse. When the gear is set into forward position the solenoid loses its current and a mechanical return spring opens the valve, so that the overrun brakes may act normally again.

Methods, apparatus, systems and articles of manufacture are disclosed for automatic calibration of electronic trailer brake gain. An example apparatus includes a trailer brake gain calibration module programmed to compare a calculated trailer brake torque to at least one of a first or second threshold, adjust a gain value based upon satisfaction of at least one of the first or second threshold, and apply a pressure to a trailer brake based on the gain value.

This electric braking device transmits power generated by an electric motor to a pressing member and causes pressing force to be generated by the pressing member with respect to a friction member. The electric braking device includes a lock mechanism. A locked state (in which movement of a locked section in a direction in which pressing force decreases is impossible) is achieved in the lock mechanism by: performing supplied power amount reduction control in which the amount of power supplied to the electric motor is reduced while a locking member is maintained in a lockable position; causing the locked section to move in the direction in which pressing force decreases; and causing the locking member and the locked section to engage. When performing supplied power amount reduction control, the amount of power supplied is first reduced by a large reduction gradient and then reduced by a small reduction gradient.

A overrun brake system includes a gas spring with a gas-tight cylinder and a piston with holes allowing gas to slip through so that the pressure is the same on both sides. Since the free end of the piston has a larger area than the side where the piston rod is located, the gas spring will act as a compression spring. To prevent the overrun brakes from being activated during reversing, the gas spring has a solenoid controlled valve receiving current from the reverse light circuit and closing the flow of gas through the piston when the towing unit's gear is set into reverse. When the gear is set into forward position the solenoid loses its current and a mechanical return spring opens the valve, so that the overrun brakes may act normally again.

This electric braking device transmits power generated by an electric motor to a pressing member and causes pressing force to be generated by the pressing member with respect to a friction member. The electric braking device includes a lock mechanism. A locked state (in which movement of a locked section in a direction in which pressing force decreases is impossible) is achieved in the lock mechanism by: performing supplied power amount reduction control in which the amount of power supplied to the electric motor is reduced while a locking member is maintained in a lockable position; causing the locked section to move in the direction in which pressing force decreases; and causing the locking member and the locked section to engage. When performing supplied power amount reduction control, the amount of power supplied is first reduced by a large reduction gradient and then reduced by a small reduction gradient.