一、前言内燃机的气阀弹簧应能在整个机器转速范围内提供足够的力使推杆和凸轮始终保持接触。当然,这个力也不能太大,否则推杆和凸轮之间的接触应力会过高。对气阀弹簧的基本要求是一旦断裂或卸载,它都不应变得太松以致使推杆和凸轮之间失去应有的接触力。 I. INTRODUCTION Internal combustion engine valve spring should be able to provide sufficient force throughout the machine speed range so that the pushrod and cam always remain in contact. Of course, this force can not be too large, otherwise the contact stress between the push rod and the cam will be too high. The basic requirement for a valve spring is that it should not become too loose in the event of breakage or unloading so that the proper contact force between the push rod and the cam is lost.