Clutches And Brakes Flashcards
What are the 3 ways transmission of torque can take place?
- Friction
- Electromagnetic flux
- Mechanical lock up
What are the 5 actuation methods of clutches and brakes?
- Hydraulics
- Pneumatics
- Mechanical
- Electrical
- Self actuated
What are the 2 types of magnetic and electromagnetic designs?
- Magnetic particle
- Eddy current
How are magnetic particle designs engaged?
By energizing a coil that creates lines of Flux
How are eddy current clutches and brakes engaged?
With DC current and there has to be relative motion/shaft rotation
What is the most common type of clutch and brake for general purpose starting and stopping?
Friction type
What is the oldest and most basic of clutching methods?
Mechanical lock up
Advantage of a square jaw clutch?
Provides instant positive engagement in either direction of rotation (Bidirectional)
What are the 2 disadvantages of a square jaw clutch?
- No slippage 2
- Running engagement is only possible up to 10 rpm
Multiple tooth clutches are a refinement of what type of clutch?
Square jaw clutch
What does over running mean?
That it can drive in one direction and free wheel in the other
Explain wrap spring clutches?
The are unidirectional and drive in one direction and free wheel in the other.
Explain Sprag clutches?
They’re overrunning, unidirectional, they are just like a ratchet or a 10 speed bike, they will drive in one direction and when the rotation is reversed, they will slip
One way clutches are also know as what?
Back stopping clutches
Explain ramp and roller clutches?
Unidirectional, similar to a Sprag clutch and if the outer race is mounted stationary the unit will free wheel in one direction and lock in the other (back stopping)
