低波动三缸单作用往复泵采用的曲拐凸轮轴以3个相位差120°的特制凸轮改变了活塞的运动规律，使活塞运动达到理想要求。对低波动三缸单作用往复泵曲拐凸轮轴进行优化设计时，在满足泵活塞运动规律和强度条件下，以凸轮体积最小原则设计凸轮，建立优化设计数学模型。对曲拐凸轮轮进行了受力分析，在按弯、扭联合作用进行疲劳强度校核时，截面内力计算不应少于36个点。这种优化设计是一种经济实惠的设计方法，可使同参数泵结构紧凑、外形美观、重量轻。 Low fluctuation three-cylinder single-action reciprocating pump used crank camshaft with three phase difference 120 ° special cam changed the movement of the piston, the piston movement to achieve the desired requirements. To optimize the design of low-fluctuation triplex single-acting reciprocating pump crankcock camshaft, the optimal design mathematical model is established based on the principle of minimum cam volume under the condition of the law and intensity of pump piston movement. The force analysis of the crank cam is carried out. When checking the fatigue strength according to the combined effect of bending and twisting, the internal force of the section should not be less than 36 points. This optimized design is a cost-effective method of design that allows the same parameter pump to be compact, attractively shaped and lightweight.