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1 前言汽车起重机的二次下滑现象,即把重物从地面提升停留在空中,当第二次再提升时,重物先下降一段距离后再上升。它影响了汽车起重机的使用范围。本文就如何防止二次下滑现象的方法,谈一点看法。2 二次下滑产生的原因图1是我国目前广泛采用的一种起升油路。其工作原理是,当换向阀1处于中位时,液压泵来油P→0,制动器4处于关闭状态。这时,靠制动器的制动力矩防止重物下滑。当换
1 Introduction The second decline of truck cranes is to lift heavy objects from the ground and stay in the air. When they are lifted again for the second time, the heavy objects first descend and then rise. It affects the use of truck cranes. This article talks about how to prevent the second decline. 2 Reasons for the Second Decline Figure 1 is a hoisting oil road that is currently widely used in China. The working principle is that when the reversing valve 1 is in the neutral position, the hydraulic pump comes to P→0 and the brake 4 is in the closed state. At this time, the braking torque of the brake prevents the weight from falling. When changing