トラクタ駆動輪のすべり沈下について (第2報)

接地圧, 接地長, すべり率およびすべり沈下量の関係

抄録

The aim of this study is to find out the transient phenomenon of slip sinkage of the drive wheel in operation with drawbar pull.
In this paper, the following items were found experimentally and discussed:
1) Relation between the silppage, s and the potential sinkage h₀ which is the sinkage at the steady state running of vehicle.
2) Transient phenomenon of slip sinkage of the driving wheel.
3) Relation between the contact length of the driving wheel, the contact pressure and the sinkage.
Results are summarized as follows:
1) A transient phenomenon of the slip sinkage of a driving wheel can be simulated approximately as equations (2) and (7). They are
dh/dt=K (h₀-h) (2)
dh/dt=K₁h (h₀-h) (7)
2) Relation between the potential sinkage h₀ and the slippage s when the initial static sinkage is not considered, can be exprssed as
h₀=0.57s+3.44 (19)
3) Coefficients K and K₁ are related to the slippage respectively as follows:
K=-0.15s+13.06 (20)
K₁=-0.4 (s/75-1.0) (21)
K and K₁ decrease with an increment of slippage s.
4) The contact length was almost constant in spite of an increment of sinkage. The ratio α/β is proportioanal to the sinkage (h_s+h₀) when the initial static sinkage h_s is considered. This is the reason why the angle α increases when the wheel sinks.
5) The maximum contact pressure has a negative linear relation to the sinage (h_s+h₀) because the increase of sinkage promotes the slippage of the driving wheel and it results in the increase of an angle α.