Studies of Cherry Harvesting by Shaking Small Limbs

日本的工艺樱桃产量约为4000吨/年。所有这些都是手工采摘的。由于劳动力短缺的问题，人们希望采用机械收割。1994年，我们尝试用商用日本杏摇壶摇樱桃树的小树枝来收获樱桃。然后诱导出许多无茎果实。1995年，我们对振动筛进行了改进，使其产生更大的冲程（8cm），并进行了现场试验。结果表明：该方法果实收获率高，落果多为带柄。收获后立即加工得到的产品几乎没有损坏。1996年，我们将一个大冲程产生箱转移到动臂底部，并在动臂顶端安装了夹子而不是钩子，这样一个人就可以连续地进行收获作业。现场试验发现，采收时应在成熟前期进行机械采收，采收过程中，振动筛产生的振动几乎不可能传递到细长的枝条上，采收过程中几乎不破坏树皮。为了研究樱桃果实的可拆卸性，进行了振动试验和拉力试验。在6 ~ 8 cm行程的振动试验中，获得了带柄的果实。而无柄果实则是由每个离核都有许多果实和叶片的体系产生的。在拉拔试验中，由于果实质量较小，茎与茎之间的分离力（SS力）小于茎与果实之间的分离力（SF力）。但当质量变大时，SF力约为SS力的三分之一。当樱桃果实被拉向与茎相反的方向时，分离力变得非常低。通过对枝条修剪、训练方法和栽培方法的改进，将使振动工艺樱桃采收具有实际应用价值。

Process-cherry production in Japan is about 4,000t/year. All of these are harvested by hand picking. Because of the problem of shortage of laborers, a mechanical harvesting has been desired.In 1994, we tried to harvest cherry fruits by shaking small limbs of cherry trees using commercial Japanese apricot shakers. Then many stalkless fruits were induced.In 1995, we modified the shaker so that it may generate a larger stroke (8cm) and field test was conducted. The results obtained showed that the fruits harvesting percentage was high and most of the dropped fruits were with their stalks. The products, obtained by processing immediatly after harvesting, were with little damage.In 1996, we transfered a large stroke generating case to the bottom of the boom and set the clamp instead of the hook at the tip of the boom, thereby a single man could perform harvesting operations consistently.In field test, it was found that a mechanical harvesting should be done in pre-stage of maturity, the vibration generated by the shaker could hardly be transmitted to the slender limb and the bark hardly was damaged during the harvesting operations.A vibrating test and a pulling test were carried out in order to investigate the detachable properties of cherry fruits. In the vibrating test with 6 to 8 cm of stroke, fruits with stalk were obtained. But the stalkless fruits were resulted from the system which had many fruits and leaves per the spur. In the pulling test, the detachment force between spur and stalk (SS force) was lower than that between stalk and fruit (SF force), as the fruit mass was smaller. But when the mass became larger, SF force was about one third of SS force. As a cherry fruit was pulled in the opposite direction of stalk, the detachment force became extremely low.By improving the pruning and training methods of branches and the methods of cultivation, the vibrational process-cherry harvesting will be able to be used practically.