【作者】 柳恩芬；

【导师】 张心明； 张玉海；

【作者基本信息】 长春理工大学 ， 机械工程， 2007， 硕士

【摘要】 中心阀式制动主缸是配备装有ABS自动防抱死制动系统的汽车部件。早期主要配置较高档的轿车。90年代中期以后，国内许多中档轿车也开始大面积配置ABS系统。但由于我国轿车工业和相关零部件产业与国际先进水平还有很大差距，中心阀主缸产品在2000年以前国内还没有任何厂家生产。 普通的制动主缸是补偿孔式结构，存不工作时主缸的高压腔通过其缸壁的补偿孔与油杯相通，保证供油。制动时推杆推动活塞向前运动，带动皮碗向前通过补偿孔后形成密封腔，产生液压。每次建压皮碗就通过补偿孔一次，不利于皮碗的耐久使用。 中心阀主缸结构上完全区别于普通主缸的密封方式，是在活塞中心设置一个阀门机构，该机构由装入活塞内的中心阀弹簧、中心阀芯、阀体部件和装在活塞上的弹簧座组成。在非工作时，阀门处于常开状态，使高压腔与低压腔相通。制动时推杆推动活塞向前运动，而中心阀芯在中心阀弹簧的作用下相对活塞及阀体部件向后运动，使阀门关闭，产生液压。在ABS作用下液压随着轮速传感器的信号不断调整液压，以防车轮抱死。 中心阀制动主缸较补偿孔主缸改善了畅通性、灵活性和可靠性，提高了使用寿命。但其加工难度较大，成本较高。更多还原

【Abstract】 Central Valve (hereinafter referred to "CV") type Brake Master Cylinder is designed for automobile equipped with Anti-Block System (hereinafter referred to ’"ABS"). At the very beginning, CV Master Cylinder was mainly installed on high-end cars. From middle of 1990’s on, some local mid-end cars begin to be equipped with ABS, but there exists big gap between Chinese car industry as well as relevant parts and international advanced. So CV master cylinder has not been put into product yet round China before 2000.Common design of brake master cylinder has a hole. At released position, the hole connects working chamber to brake fluid reservoir so as to provide brake fluid. At brake position, pushrod moves forward together with piston, till seal cup passed the hole, high pressure built up in the working chamber. Each pressure building needs seal cup passing the hole, it will reduce seal cup’s working life.Sealing of CV master cylinder features totally different with that of common master cylinder, a valve unit, consisting of a central valve spring inside of piston, a central valve, valve body and a spring seat against the piston. At released position, the central valve always keeps open, working chamber connecting to supply chamber. At brake position, pushrod against the piston moves forward, the central valve moves backward relatively to the piston and valve body by force of the central valve spring, thus central valve is closed, so hydraulic pressure is built up in the working chamber. Under the influence of ABS, the said hydraulic pressure is regulated according to signal from wheel speed sensor to prevent a wheel is blocked.Compared with common design, CV master cylinder features good fluid thoroughness, smoothness and reliability, thus owns longer working life. Owing to its complicated manufacturing process, so central valve is more expensive.更多还原