Standard progression

When the spindle speed are arranged in geometric progression then the ratio between the two adjacent speeds is known as step ratio or progression ratio.

Step ratio

Preferred basic series

Design of gear box

1. Selection of Spindle speed:

Find the standard step ratio by using the relations,

2. Structural formula

It can be selected based on the number of speed:

3. Ray Diagram

The ray diagram is the graphical representation of the drive arrangement in general from. In other words, The ray diagram is the graphical representation of the structural formula.

The basic rules to be followed while designing the gear box as Transmission ration (i):