变量齿轮泵的新机制研究与微圆槽的卸荷能力分析

New Mechanism Research on Variable Delivery Capacity and Special Relief Analysis of a New Simple Micro-circle Groove for External Gear Pumps

为实现功率和排量的同步变化以节省资源,提出一款齿轮泵变量的新机构,该机构原理简单,由变量弹簧力和高压油压力的动态平衡驱动齿轮副有效啮合宽度的自动变化,从而实现泵功率和排量随有效啮合宽度的同步变化;并就其困油性能与困油卸荷进行深入研究和分析,提出具有微圆结构的卸荷槽;最后,进行实例运算和分析。结果表明:微圆卸荷槽具有更大的卸荷面积和卸荷能力;有效啮合宽度越小,困油压力峰值越小,困油性能越好;反之,困油性能越差,但影响不大。

In order to guarantee simultaneous changes of running power and variable delivery capacity for saving resources,new mecha-nism solution of external gear pumps with variable delivery capacity was proposed.The new mechanism was simple.By the dynamic force bal-ance of output oil pressure and spring force for variable delivery capacity,the dynamic effective mesh width of gear pairs was automatically de-termined,then the variable delivery capacity and synchronization running power of external gear pumps along with the dynamic effective mesh width was thoroughly realized.With respect to its trapped-oil performance and trapped-oil relief,the related deep research and analysis were operated,and the new relief groove with micro-circle profile was invented.Finally,an example computation and results analysis were executed.All results show that greater relief area and relief capacity are owned by the new relief groove with micro-circle profile;the smaller the effective mesh width is,the lower the trapped-oil pressure peak is,and the better the trapped-oil performance is;on the other hand,the poorer the trapped-oil performance is,but its degree is not big,etc.