SEED
Guides
Clutches
Environment
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2.3 Method of actuation
Actuation may be manual, automatic or semi-automatic. It is an important part of clutch design to consider this carefully. The folowing list gives the common methods of control.
- Manual - actuated by an operator, usually pulling a lever or working a mechanical linkage
- Automatic - centrifugal force or magnetic forces
- Hydraulic and pneumatic - fluid pressure drives the actuating mechanism
- Electromagnetic - an electromagnetic actuator is used
The method chosen will depend on the power sources available. Remote actuation over a very long distance would be best suited to an electrical system. Hydraulic and pneumatic actuation should only be considered when they are readily available. Extra hardware such as transformers, valves, etc., may be needed. These items increase system cost and require extra design time. Manual control or over-ride may be necessary. Where large actuation forces are used, servo-mechanisms or high mechanical advantage levers must be designed.