齿轮泵无轴向泄漏的新结构研究

Research on New Structure of External Gear Pumps without Axial Leakage

为解决轴向泄漏造成齿轮泵容积效率下降的问题,提出一款无轴向泄漏的新结构,即将普通泵直径小于根圆的滑动轴承结构,变更为直径介于根圆与节圆之间的同步圆盘轴-浮动侧板轴承新结构,两对同步圆盘轴被分别固定在主动齿轮和从动齿轮的前、后两侧。推导出压紧力和压紧力系数、轴向泄漏率的计算公式,并进行实例计算及分析。结果表明:齿轮泵无轴向泄漏结构的压紧力系数为1.18,符合小于1.2的要求;新结构轴向泄漏率仅为原结构的7%,可视为无轴向泄漏;偏心率降低了11%,最小油膜厚度增加了4%,有利于润滑改善;轴宽由15 mm变为10 mm,有利于降低轴向尺寸和轻量化设计。

In order to solve the problem of volume efficiency reduction caused by axial leakage in external gear pumps,an new structure scheme of external gear pump without axial leakage was proposed,in which a new structure of synchronous disc shaft-floating side plate bearing with diameter between the root circle and the pitch circle was used to replace the structure of sliding bearing of ordinary pump with diameter less than the root circle,and two pairs of synchronous disk shaft was respectively fixed on front-end and back-end of driving gear and driven gear.The calculation formula of compression force and compression force coefficient and the axial leakage were derived.an example of calculation and analysis was given.The results show that the compaction force coefficient of the new structure of gear pump without axial leakage is 1.18,which meets the requirement of less than 1.2.The axial leakage rate of the new structure is only 7%of that of the original structure,which can be really regarded as no axial leakage.The eccentricity is reduced by 11%,and the minimum oil film thickness is increased by 4%,which is helpful for lubricating performance improvement.The bearing width is reduced from 15 mm to 10 mm,which is helpful for reducing axial size and lightweight design of gear pumps.