Mitsubishi MELSEC-F, Training Manual

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Positioning Control The World of Positioning Control 1
1-2
1.2 Diversified actuators
• A power source which moves an element in a system is called actuator. A unit which detects
a position of a work piece or moving part is called sensor.
• Diversified actuators and sensors, from simple ones to enhanced ones, are used in
positioning.
• This paragraph describes representative types, their features and weak points.
Pneumatic
• Air source and high grade piping are
required.
• High torque is not available.
• Multi-point positioning is complex and
very difficult to achieve.
• Change in positioning is difficult.
Brake motor
• Positioning mechanism is simple.
• Repeatability is poor.
• Change in positioning is difficult.
(When optical sensors or limit switches are
used for stop)
Clutch brake
• Frequent positioning is available.
• Life of friction plate is limited.
• Change in positioning is difficult.
(When optical sensors or limit switches are
used for stop)