Pulley systems Flashcards
What is a pulley system?
Uses a belt to transmit motion and force from one wheel to another
What is a V belt?
Tightly fits the grooves of the pulley and gives a large surface area
Advantages and disadvantages of a V belt:
Large SA means it’s less likely to slip and allows more torque to be passed through it
Over time they stretch (nylon, cotton, steel core helps to reduce the stretch)
What is a round belt?
Used when small forces are involved or where the belt has a twist
Advantages and disadvantages of a round belt:
Flexible and light
Don’t have a large surface area so they’re prone to slipping
Where are round belts used?
Hoovers and sewing machines (rotary motion)
What is a linked belt?
When it’s impossible to have a continuous belt fitted to a system
Advantages and disadvantages of a linked belt:
If a link breaks only the link needs to be fixed
Not a lot of torque
What is a multi belt?
Multiple V belts work together to produce a high level of torque and it’ll still work if one belt breaks
What is a toothed belt
Has little teeth to prevent slipping
Advantages and disadvantages of a toothed belt:
Prevents slipping and is more accurate, a lot of power and torque
No disadvantages
How does the amount of tension affect the belt?
Tension helps the belt system be more efficient
Too tight -> it won’t work as well
Too slack -> less efficient as there will be slippage
What is a tension pulley?
Can be adjusted to take account the gear reaction when the pulley stretches
