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A current-driven electromagnet is a traction electromagnet that converts electrical energy into a magnetic force to drive a guide rod and do work externally.  When the current is energized, the current-receiving electromagnet generates magnetic force through the solenoid electromagnetic coil, drives the moving iron core inside the coil, drives the guide rod to move along the axial direction, drives the current-receiving parts connected with the guide rod earring, and completes the on-off action of the current.  After power off, the magnetic force disappears and the guide rod is reset by spring.