Studies on harvesting machines (XI)

Cutting resitance for crop stems (3)

Abstract

In order to design harvesting Machines, we have to know the power and the minimum velocity for cutting of crop stemes.
We have reported the cutting resistance of one stem of crops, which was measured by EI-1 type testing machine.
Now, we manufactured EI-2 type testing implement (fig. 1) and found the minimum cutting velocity to have one stem cut by the sliding knife section.
(1) The minimum cutting velocity showed a trend to decrease as the wedge angle of the knife section decreased when inclined angle of the knife section was constant and the sliding knife section cut a piece of crop stem.
(2) There was optimum inclined angle of the knife section getting the minimum velocity, the wedge angle being constant.
(3) The minimum cutting velocity for crops was as follows;
Rice stem>Wheat>Milk vetch
Cutting by the knife section; 2-4m/s
Cutting by the knife section with ledger plate; 0.7-1.7m/s
(4) The static cutting resistance of one stem of crcps using the knife section with ledger plate was as follows (inclined angle was 30°);