Displacement control

Displacement control

The displacement is changed by the different sloping of the connecting rod holder plate (1), which takes place by changing the balance of the pressures - thus of the forces - acting on the plate itself.

This balance is changed by the opening of the diaphragm valve (4) according to the following logic:

• with high intake pressure (Pa) the valve (4) stays shut; the main action on the plate (1) pivoted in (2) is by the reaction forces of the pistons P1, which cause a clockwise movement M1 applied at the fulcrum of the plate, which remains in the most inclined position.
• if the Pa falls, the difference in the pressure at the diaphragm opens the valve (1); this generates a thrust pressure on the shaft (3) which involves a resulting P2 which causes a counterclockwise movement M2 which tends to turn the plate (4) towards a more vertical position, i.e. a gradual reduction of the displacement.

COMPRESSOR - 2.0 T.S. 16v Engine

This compressor is a NIPPONDENSO TV14SC with variable displacement: the change in this parameter is carried out automatically by the compressor in relation to the load (difference in the pressure up and downstream of it): a special valve controls the opening of a by-pass which shuts off part of the fluid from the compression stroke; the displacement can be reduced to 17% of the maximum rate.

Adjustment takes place on the inlet pressure:

• a low inlet pressure will make the system reduce the displacement. This happens for instance when the cooling cycle is working in the best conditions : high engine rpm (and of the compressor), high thermal exchange at the condenser etc.; (without a compressor with this variable configuration the compressor would cut in and out continuously);
• a high inlet pressure, on the other hand, increases the displacement to its maximum value. This happens for instance with low engine rpm and high requirements for "cold".