10.4.2. Summary
The engine output depends upon the supplied fuel quantity and the engine efficiency. In order
to transform into the effective work of engine by burning the supplied fuel fully, the sufficient
air to burn the fuel should be supplied to the cylinder. Therefore, the engine output is
essentially determined by the size of the cylinder, and for if the air is supplied to the given
volume of cylinder with the air being compressed, the air quantity in the cylinder will Increase
as much to result in that it may burn more fuel. the output will also be able to increase,
Supplying the air by compressing like this into the engine cylinder is called as super charging,
and super charging by means of exhaust gas energy that discharges to the atmosphere is
called as the turbo charging.
10.4.3. Function
10.4.3.1. Turbine
The exhaust gas that is discharged from combustion chamber passes through turbine
housing conveying an energy to turbine wings to give the rotating power, This is called as
the turbine and in order not to influence a bad effect at bearing part, there are the seal ring
and heat dissipator.
10.4.3.2. Compressor
It is connected to the same shaft with the turbine to make a revolving assembly, and receive
the revolving force of turbine, and sends air to the suction manifold by suctioning and
compressing it. This is called as the compressor.
10.4.3.3. Bearing
•
Thrust bearing force is applied to the turbine wheel and an arrangement is made for the
shaft not to shift.
•
Journal bearing (floating bearing) is adopted and it forms the double oil films at the in out
surfaces in comparison to the general stationary type so that the bearing may be able to
rotate independently and consequently the double layers of films act as the damper to
make the slipping speed on the bearing surface less than the rotating speed of shaft so
that the dynamic stability may be obtained.
10.4.3.4. Sealing at Compressor shaft
In order for the compressed intake air and lubricating oil not to leak, a seal plate and a seal
ring are made to the double structures.
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EFM3002I
Turbine wheel
Compressor wheel
Compressor air supply
Exhaust
Exhaust gas inlet
Outlet
EFM3003I
Turbine
Intake air
inlet
Compressor air passage
Compressor
Exhaust gas passage
Exhaust
gas
outlet
Engine
cylinder
