Unlike the better balanced straight-six or even the ultra-smooth V-12 engine, the humble four-cylinder generates an up and down vibration with a frequency of twice the crankshaft's rotational speed.

不像运行起来比它更稳定的直列六缸引擎或者极其流畅的V - 12引擎，卑微的四缸引擎会以一种比自身机轴转速高两倍的频率产生一上一下的振动。

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In this paper, the vibration mechanic at model for a no-base, V-type positon air compressor is deduced, some elementary problems of design and calculation of damping system are expounded.

本文导出了无基础V型活塞式空气压缩机振动的力学模型，阐述了减振系统设计计算的基本问题。

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The machines have four types of functional heads: vibration cutting head, creasing wheels, V-cutter, high speed milling Router, with drawing pen.

机器有四个功能头：振动刀切割头、压折线轮、V型切割头和高转速铣刀头。

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