Binding Performance of Binder (II)
Factorial Analysis of Sheaf Properties
1973 Volume 34 Issue 4 Pages 344-352
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1973 Volume 34 Issue 4 Pages 344-352
The four kinds of factorial experiments (The Experiment I-IV designed by the split-plot method with fixed and random effect models) were carried out in the fields to obtain the fundamental data which would enable to simplify the design of binding mechanisms of the binder when the physical properties of stalks and sheaves were taken into account.
In this paper, the specific value P shown by expression (3) was defined to express the tightness of the bound sheaf. And at the results of measuring values of Experiment I, the weight of sheaf (w), the breadth (d) and length (d′) of binding cross-section of sheaf, the twine length of binding sheaf (L), its tension in d′ direction (T) and those composite variables which concerned with P were analyzed by the use of the variance analysis and the correlation methods.
Those results were summarized as follows;
1. The weight of sheaf was affected by the field conditions as well as the other various factors.
2. The natural drying of sheaves was affected by sheaf sizes. And it had direct effects upon the value of T.
3. T decreased rapidly until 60-55% of the water contents of sheaf and at 47-43% of the water contents of sheaf (10 days after), 18-16% of the inicial twine tension were remained.
4. The remaining rate of twine tension (KT) was larger with small sheaf sizes than the big sizes, and affected by physical properties of twine more than the sheaf sizes.
5 If the twine brake was set at constant for the three kinds of tested twine, W and L increased with the sheaf sizes respectively, but the differences among the kinds of twine were not significant.
6. T and the shape of binding cross-section of sheaf were affected by the physical properties of straws and twine.
7. It seemed that the compressibility of straws in a sheaf was influenced by the stress relaxation and elongation of twine and the coefficient of friction and the imaginary contacting area between the twine and stalks. But its effects were very small as the effects of water contents and sizes of sheaf.
In the next papers, we shall be analyzed the relationship retween the tightness of bound sheaf and the binding mechanisms of binder by the use of P calculated by the results of Experiment I.
