游梁行星轮组合式长冲程抽油机

游梁行星轮组合式长冲程抽油机的设计要点是，在旋转驴头上固接一个与之同轴心的行星齿轮，在机架上固接一个以游梁支点为圆心的齿轮轨同驴头行星齿轮相啮合，使驴头既可随游梁摆动，还可大角度自转，从而有效地增大冲程。导出了这种抽油机的悬点速度、加速度及冲程的计算公式。最后还将这种抽油机同常规游梁抽油机和无游梁长冲程抽油机作了比较。

A Long-Stroke Pumping Unit with Self-Rotating Horsehead

The key point of designing a long-stroke pumping unit with self-rotating horsehead is installing a coaxial planet gear on the horsehead engaging with a circular gear rack(taking the fulcrum of walking beam as its center)fixed on the framework of the unit to enable the horsehead to rotate by itself simutaneously while swinging with the walking beam to increase thestroke length of the unit. The authors work out the equations for the polished rod speed and acceleration and the stroke length, and compare the new unit with the conventional beam Pumping unit and the lollg-stroke Pumping unit without walking beam.