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MECHANICAL ACTUATION METHOD
Figure 11.3: Schematics symbol of mechanical actuation method
Various mechanical devices are used to control a direction control
valve, e.g., roller, plunger, roller tappet, spring, etc. The roller tappet
is pushed in by a cam or a similar device and pressed on the spool. A
very common mechanical actuator is a plunger. With a roller at its top,
the plunger can be actuated by a cam which can be attached to the
cylinder. The mechanical actuation is used the shifting of a directional
control valve must occur at the time cylinder reaches a specific
position. A spring is very often used to reset the valve position for both
manually and mechanically actuated valves described below.
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