It absolutely was initial launched in 1939 for vehicles. It is made up of the fluid coupling and 3 planetary gears. They collectively make three forward and one particular reverse pace. There's no clutch for engagement and disengagement in the motor. Bevel gearboxes have spiral and straight tooth shapes. https://andersonqrrom.ambien-blog.com/40226431/the-2-minute-rule-for-gearbox