【摘要】 为降低能耗．减少污染．满足现代车辆对发动机冷却系统结构尺寸和噪声的要求，最新的方法之一是应用电液比例技术控制发动机冷却风扇的转速。分析对比了多种电液比例技术控制风扇转速的方案，并重点介绍了比例压力阀控制方案的原理及特征。更多还原

【Abstract】 In order to lower energy consumption , reduce pollution and satisfy the demand of modern motor vehicle for constructional size and noise of engine cooling system,one of the newest method is to control the turning speed of engine cooling fan with proportioning technology of elec tricity and hydraulics. Various fan speed control schemes of proportioning technology of electricity and hydraulics are analized and compared. Principle and characteristics of proportional pressure valve control scheme is emphatically introduced.更多还原