Design and Experiment of ф-type-knots Knotters on Chinese Small Square Balers

Content:Since the knotters on the Chinese rectangular balers areimported from outside of the country, Chinese knotters withindependent intellectual property rights is far away from being closed. In order to harvest a large quantity of straw in a short period onthe small-scale lands of China, basic requirements on the knotters aresummarized. Mathematical model of the knotter is also determineduniquely. Furthermore, theф-type-knots knotter equipped on the Chinese square baler to form theфtype knots is designed. Knottingrate experiments of theф-type-knots knotter on the test bench and in the wheat/maize straws covered fields are carried out to check theknotting performances of the knotter. The parameters of the formedknots are also tested. The experiments results show that theknottingrate of theф-type-knots knotter reaches 100.0% on the test bench without straws, while reaches 99.6% in the wheat straws covered fieldand 100.0% in the maize straws covered field. The average maximum force in the knotting process is 194.7 N in the lab experiment. Thelength out of the knots formed in lab is 15.9%–20.6% lower thanthe knots formed in the field experiment. The breaking force oftheknots formed in the field is 115.9%–167.2% higher than the knots formed in lab due to the higherpreload and interactions withthecompacted bales. Highly relevantrelationships exist between the breaking force ofthe formed knots and the maximum force in theforming process of the knots in the lab experiment. The designed knotter breaks out the embarrassing situation of the domesticknotterswhich don’t have independent intellectual property rights, andpromotes the development of Chinese knotter technology, and themathematical model is helpful for designing new type of knotters.