Abstract Based on the fact that normal gear pump has defects of poor quality flow and imbalanced radial force， the design of a new type of balanced cosine gear pump with outer gear was presented. This new type of cosine gear pumps not only retain the general structural features of normal gear pumps， but also have good flow quality，high power density，balanced radial force of center wheel and can suffer large displacement as well. The effect of the center gear's tooth number on the pulse rate of pump flow was researched. Results show that the flow pulse rate of new cosine gear pump is only one third of normal cosine gear， which improves the quality of the gear pump's flow. Therefore， this new type of gear pump can expand application of gear pump， and has some research and application value．
TANG Liang-Bao, CHEN Ji-Jun. Research on the structure and performance of balanced external cosine gear pump. Chinese Journal of Engineering Design, 2010, 17(4): 312-316.
