# MEC Overdrive Unit

## 創新系統

The Overdrive Unit, "MEC", includes a set of epicyclical gears that represent an application of a simple epicyclic arrangement of the type used in a motor vehicle overdrive.

## 一般說明

The Overdrive Unit, "MEC", includes a set of epicyclical gears that represent an application of a simple epicyclic arrangement of the type used in a motor vehicle overdrive.

A simple epicyclic set consists of:

• Sun gear that rotates together with the input shaft.
• Planet gears whose carrier can rotate.
• Ring gear that rotates together with the output shaft.

In the "MEC" unit the power reaches the epicyclic gear through the central sun gear, that is to say, the input shaft is joined to the central sun pinion and the output power is obtained at the output shaft because it is joined to the ring.

This unit allows the student to study the reduction ratios of overdrive, as well as torque conversion.

## 練習和指導練習

### 手册中包含的指导实践练习

1. To study the overdrive speed.
2. To demonstrate the operation of an epicyclic gears system to obtain the overdrive speed.
3. To determine the angular displacement at the input and output and to compare it with the overdrive reduction ratio calculated.
4. To determine the minimum effort required at the input to raise a load at the output in an overdrive reduction ratio.
5. Power transmission: checking the ratio between input torque and output torque for an overdrive reduction ratio.