As the crankshaft rotates, the crankpin swings in a circle around the shaft. 隨著(zhù)曲軸的轉動(dòng)，曲柄銷(xiāo)繞主軸作圓周擺動(dòng)。
The former causes forced vibration at the circular frequency of the crank shaft and the latter causes transient vibration at the natural frequency of the press. 慣性力激發(fā)的振動(dòng)是以曲軸轉速為頻率的強迫振動(dòng)，加工力激發(fā)的是以壓機固有頻率為頻率的過(guò)渡振動(dòng)。
Every bike has a serial number near the crank shaft. 每輛自行車(chē)在曲柄軸附近都有一個(gè)序列號。
