Deceleration starter
A starter with a gear reducer installed between the armature shaft of the starter and the drive gear is called a deceleration starter.
The power of a series-excited DC motor is proportional to the torque and speed of the motor. It can be seen that when the engine speed is increased while the torque is decreased, the starter power can be kept unchanged. Therefore, when a high-speed, low-torque series-excited DC motor is used as the starter, under the condition of the same power, the volume and weight of the starter can be greatly reduced. However, the torque of the starter is too low to meet the requirements for starting the engine. For this reason, when a high-speed, low-torque DC motor is used in the starter, a gear reducer is installed between the motor’s armature shaft and the drive gear, which can reduce the motor’s speed and increase its torque.
The gear reducer of the deceleration starter has three different forms: external meshing type, internal meshing type and planetary gear type.