Clutches And Brakes Flashcards
3 types of electric and magnetic clutches
Hysteresis
Magnetic particle
Eddy current clutch
What is a hysteresis clutch
Uses a eltromagnetic coil on the input and a hardened steel cup positioned on the output shaft
Do electromagnetic clutches ever have contact
No
3 type of positive contact clutches
Sqaure jaw
Spiral jaw
Multiple tooth
Can positive clutches be engaged at high speeds
No
Can u spin a sqaure jaw in only one direction
No it’s bidirectional
At what speed can a square jaw clutch be disengaged
Any speed as long as it’s not transmitting high torque
What material are used on the friction clutch faces
Non metallic
Metallic
Or both
Which face plate is harder, pressure plate or friction lining
Pressure plate
Two types of radial friction clutches
Expanding shoe clutch
Contracting shoe clutch
What are expanding shoe clutches
Shoes that are connected to the shaft and expand outwards to engage
Usually have a lever to engage
Two advantages of a contracting shoe clutch
Engage and disengage quickly
Variety of sizes and used for very high horse power
3 types of axial friction clutches
Single friction
Multiple disc friction
Cone
At what angles are cone clutches kept at
10 to 15 degrees
3 basic types of couplings
Rigid
Flexible
Special purpose
What are rigid couplings
Provide a fixed union between two shafts
Why are sleeve couplings used
For low speeds and low torque
What is a compression coupling
Grips shaft using tapered sleeves in tapered hubs
What should be the failure point in a coupling
The key
When are rigid couplings used
Heavy load and torque
Easy removal and installation
When are flange face couplings used
Connect shafts of the same diameter or of shafts with different diameters
Where are threaded couplings used
Vertical pumps
Shaft must be spinning same direction as threads
What’s is the most common coupling
Flexible coupling
3 ways a flexible coupling are classified
Mechanical flexibility
Material flexibility
Combination
