《农业机械》杂志1994年第10期第27页“小四轮拖拉机液压系统故障一例”一文中,对柱塞式液压油泵驱动轴承损坏的原因进行了分析。该文认为轴承损坏是由于柱塞上方油压过高所致。笔者认为不是由于油压过高,而是由于钢球2(见右图)卡入了柱塞4的上平面与泵油腔5的顶面之间,现分析如下。如图所示,钢球2、挡销3和柱塞4的轴向孔(钢球球座)三者构成吸油单向阀。挡销折断后,该单 “Agricultural Machinery” magazine No. 10, 1994, p. 27 “small four-wheel tractor hydraulic system failure case ” article, the plunger hydraulic pump drive bearing damage is analyzed. This article considers bearing damage due to excessive oil pressure above the plunger. I believe that not because of the oil pressure is too high, but because the ball 2 (see right) stuck in the upper surface of the plunger 4 and the pump chamber 5 between the top surface, are analyzed as follows. As shown in the figure, the steel ball 2, the stopper pin 3 and the axial hole of the plunger 4 (steel ball seat) constitute the suction check valve. After the pin is broken, the single