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Variable-cylinder compressors
The pistons are displaced by a variable-angle
oscillating plate.
This angle depends on the energy requirements
and the pressure and temperature at the inlet and
in the compressor shell.
The greater the need for cold, the larger the cylin-
drical capacity (maximum plate angle).
LP
HP
Maximum capacity
Minimum capacity
LP
HP
Variable-cylinder compressors offer a number of
advantages:
g
Reduced vehicle energy consumption
g
No surges when starting and stopping
g
Smooth changes in the can temperature
The flow is regulated by changing the stroke of the
pistons by varying the angle of the oscillating plate.
g
The angle of the plate is determined by the
pressure inside the compressor housing.
g
The position of the oscillating plate is controlled
by a valve.
g
This valve may be controlled internally using a
pressure-sensitive element, or by an external
electrovalve controlled by an electronic control
unit (ECU)
Minimum capacity
LP
HP
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