What is Backlash in Gears?
Backlash is the amount of clearance between the teeth of two mating gears. It is the looseness of the fit between the two gears.
The purpose of backlash is to provide room for expansion and contraction of gears due to temperature changes. It also allows for self-alignment of meshed gears which provides smoother running without excessive friction or binding.
Types of Backlash
- Radial Backlash – This is the most common type of backlash and refers to the amount of clearance between the teeth of two meshed gears when they are rotated in the same direction.
- Axial Backlash – This type of backlash refers to the amount of clearance between the teeth when the gears are rotated in opposite directions.
- Lead Backlash – This type of backlash refers to the amount of clearance between the teeth when the gears are driven in opposite directions at different speeds.
How to Control Backlash
- Increasing the quality or hardness of the gear materials.
- Increasing the number of teeth in the gear set.
- Installing adjustable shims between the gear teeth to reduce backlash.
- Installing thrust washers between the gear set.
- Using double helical gear sets.
Backlash in gear sets can cause excessive noise and vibration. Additionally, excessive backlash can cause the gears to slip and impact the performance and reliability of the gear set. To ensure the best performance and reliability, it is important to minimize the backlash in gear sets.