油膜測定に関する一寄与

抄録

In connection with our research on oiliness we measured the thickness of oilfilm and the breaking load of the film. The measuring method is as follows.
We measured the capacity of the condenser which is composed of lubricating oil and two metal plates with the oil in between. By elementary formula we calculated the thickness of the oil from the capacity. So we came to know the relation between the load on the metals and the thickness of oil and also the load which will break the oil film.
At the appendix we show how to make relate this result to our research on oiliness. It is as follows.
Lubricating oil has two different natures which serve to lubrication: -viscosity and oiliness. The relation between lubricating ability and viscosity is almost clarified by many previous reserches, but the relation between lubricating ability and oiliness still remains unexplained. Generally, the following definition on oiliness described in many books is believed to be correct: -“Oiliness is the nature gives the difference to frictional coefficient which does not arise from viscosity under the same condition.”
Lubricating ability at the condition of boundary friction should be measured by the ability of oil covering metal against tearing force to it, not the matter of friction. So this definition does not touch the essential nature of it, we need essential one.
We give a new definition on it from this viewpoint as follows:-“Oiliness is the nature of covering metal by physical and chemical binding force of oil and the metal.”We give the idea how to show the tendency of the magnitude of oiliness and how to measure the magnitude. By measuring the breaking load for given metals and oils at every temperature, we can plot the temperature-breaking load diagram.
This shows the tendency of the magnitude of oiliness, because the breaking of oil film by frictional force is similar to the breaking by dead load. We can choose the best lubricating oil from the diagram for given metals. This is the relation.