[Judgement of oil level]
When sufficient oil is in the crankcase, both of inner and outer electrodes are immersed in the oil through which current flows across the electrodes. The sensor judges that oil in the crankcase is sufficient. When oil level goes down and the inner electrode is exposed to the air due to consumption of oil, no current flow between the electrodes as air is considered to be electrically nonconductive. The sensor in this case judges that oil is insufficient.
[Decision of oil shortage]
Oil level at the electrodes may go down momentarily probably due to the engine being slanted or affected by vibration even if a sufficient oil is in the crankcase. For that reason, the sensor has an electronic timer circuit to prevent it from interpreting as short of oil when amount of oil is sufficient. The sensor has been designed so that the engine is to be stopped only when
[Automatic stop of engine]
When the sensor decides as
5-4-4 BLOCK DIAGRAM OF THE CIRCUIT
Power circuit
Igniter
Inner pole
Oil
Outer pole
| Detection |
| Deley circuit |
| Stopping |
| circuit |
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| circuit | |
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Engine ground
Fig.
1 Power circuit | This rectifies a part of power to the igniter and regulates it to supply the stabi- |
| lized power to necessary circuits. |
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