DESIGN AND EXPERIMENT OF HIGH LEVEL UNLOADING LARGE GRAIN COLLECTION BOX FOR FRESH CORN COMBINED HARVESTER

In response to the problems of low unloading height, small collection tank capacity, and high ear damage rate during grain collection in the fresh corn combine harvester, a large collection tank with buffering and shock absorption mechanism and high unloading height was designed based on the 4YX-6 fresh corn combine harvester, which is a fully hydraulic driven fresh corn combine harvester. The device mainly consists of a box body, a buffering and shock-absorbing mechanism, a grain unloading extension mechanism, an electro-hydraulic system, etc. According to the agronomic requirements for fresh corn cultivation, the volume of the grain collection tank is designed to be 10 m3. According to the height range of the grain receiving truck during the harvest of fresh corn, the unloading stroke height of the grain collection box is designed to be 2.9 m~4.4 m. To achieve synchronization of lifting and flipping actions during high-level unloading, a synchronous series hydraulic system is designed. Conduct force analysis on the drop of fruit ears to the bottom of the grain collection box and design a buffering and shock-absorbing mechanism. The designed grain collection box was installed on the 4YX-6 fresh corn combine harvester for field experiments, with ear damage rate and unloading time as performance indicators. The results showed that the ear damage rate ranged from 0.5% to 0.8%, the unloading time was from74 s to 126 s,and there were no safety issues such as deformation or tilting of the device during operation. The ear damage rate met the standards, and the working performance was stable, meeting the operational requirements.