Under the action of variation magnetic field, the permanent magnet moving-coil drives the plunger pump to move up and down and lift oil up to ground.

通过动力电缆给井下直线电机供电后产生交变磁场，永磁体动子在交变磁场作用下带动泵柱塞上下往复运动，从而达到举升抽油的目的。

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Nonetheless, with total disregard for his own safety, he called for his men to quickly move back to cover positions as he charged the enemy over exposed ground and under overwhelming enemy fire in order to provide protective fire for his team.

WHITEHOUSE: Medal of Honor for Staff Sergeant Robert J. Miller