Abstract
Almost all of Japanese agricultural fields are small and narrow. In addition to that, autumn rain falls frequently in tomato harvesting season. So the use of large size automatic harvesters mounted fruit-pickup-mechanism, for example those developed in the United States, are unsuitable for Japanese fields.
To save labour and also facilitate the harvesting of processing tomato fruits, a small size harvester (Type SK) was jointly developed by the Research Farm of Shinshu University and the Research Institute of Kagome Co., Ltd. in 1992.
1) The new harvester consists of a crawler tractor, fruit separater, hopper, bar conveyer, reverse turn flat belt conveyer, sorting table and a weighing device.
The full length, width, and height of the harvester are 3600, 1745, and 1445mm respectively.
2) After cutting the tomato stem with sickle or garden scissors, the entire plants are lifted by hand onto the fruit separater.
Separated and collected fruits are carried by the bar conveyer to the reverse turn flat belt conveyer for the removal of foreign matters. After then, the fruits roll down to the sorting table. One to three persons standing around the table, sort out inferior fruits. Finally, the selected matured fruits fall into a container placed on the weighing device.
3) Results from field experiments indicate that, 203.8kg/man/hour of matured fruits were harvested using the developed harvester.
This was 1.8 times higher in comparison with hand picking of fruits. The mechanical harvester engages 2 to 7 persons. But the output per person is almost the same regardless of the number of persons engaged.
4) In manual harvesting, fruit containers and others were frequently lifted up by hand while carrying, weighing and loading. The total weight of these amount to 6.66 times that of the harvested fruit weight. By using the reported harvester, the weight was reduced by 55.6%.
5) Although manual operations are still necessary, the small sized harvester described in this report, resulted in a remarkable improvement in harvest work. Its usefulness was highly prized by the tomato growers and consequently 51 machines have been manufactured between 1992 and 1994.
To further increase its efficiency, it is desirable to do more studies to come out with appropriate varieties and cultural methods.
