Chain guard, tensioning oil cylinder and assembly

The present invention discloses a flow regeneration system for an excavator boom with a potential energy recovery device, belonging to the technical field of engineering machinery equipment. It includes a boom hydraulic cylinder, a three position four way servo valve, a controller, an overflow valve, an electromagnetic flow valve, a one-way valve, a variable displacement pump, a fuel tank, and an engine; The controller is electrically connected to servo valves, electromagnetic flow valves, and variable displacement pumps; The three position four way servo valve is sequentially connected to the directional valve and hydraulic motor; The hydraulic motor is coaxial connected with the generator, and the output end of the generator is electrically connected to the supercapacitor; The outlet pressure of the hydraulic motor is controlled by an electromagnetic flow valve through the motor one-way valve; Connect the directional valve to the oil tank; The controller is electrically connected to the directional valve, generator, and hydraulic motor. The present invention can achieve the optimal energy-saving state of the excavator during the boom lowering process, reduce energy loss in the hydraulic system, improve energy utilization rate, and extend the service life of the excavator.

目前，面对当今世界的能源危机和环境的恶化，节能减排已经成为工业技术发展的一个重要方向。挖掘机在土方施工中存在着能耗高、能源利用率低的缺点。挖掘机动臂进行着往复的运动，需要频繁的制动和举升，大部分势能都消耗在多路阀口上，不仅造成能源浪费，大量的势能转化成热能，增加了燃料的消耗，而且容易引起液压系统发热，降低元件的寿命。用于挖掘机动臂的节能方案主要有流量再生和势能回收两种，多数挖掘机上动臂采用了流量再生回路，以提高工作装置的作业速度，改善复合操纵性能，使液压系统的能耗降低。但是在动臂下降过程中利用节流阀（电磁流量阀）调节动臂液压缸下降的速度时， 较多的能量浪费在了节流阀口上，能量利用率较低。随着混合动力挖掘机的发展，势能回收技术逐渐成为动臂节能的一个重要技术分支，但是单独利用液压马达回收动臂下降的势能时，动臂液压缸下腔的能量仍需要主泵提供，能量综合效率并不高。 发明内容