General Description
1 - Air-conditioning compressor
2 - Pressure line
3 - Intake line
4 - Condenser, right
5 - Condenser, left
6 - Fluid container/dryer
7 - Expansion valve
Capacity: Refrigerant R 134 a = 850 g
A continuously regulated 7-cylinder swash-plate compressor is used in the air-conditioning system. The displacement is 160 cubic.cm at 100% output. Capacity: Cooling oil = 195 +/- 15 cm ND8.
Functioning
The output of the compressor ranges between 5% and 100%.
The displacement and thus the output change resulting from changes in the swash-plate position (it moves longitudinally along the drive axle).
The higher the required cooling output becomes, the greater the intake pressure is.
The piston stroke is regulated by the high pressure/low pressure ratio.
This new pressure regulation system ensures that the compressor functions continuously in normal operation. The inclined position of the swash-plate is therefore dependent on the crank-chamber pressure and, consequently, on the pressure conditions above and below the piston. The swash-plate is held in its inclined position by springs.
The crank-chamber pressure is determined by the high and low pressure applied via a regulating valve and by a throttle bore.
The delivery volume is therefore determined by the regulating valve. The regulating valve is controlled by a diaphragm in conjunction with the intake pressure and connects the high-pressure end with the crank-chamber.
100% output
The conditions are fulfilled if the engine is at a constantly low speed and/or the temperature is high. The intake pressure is high and closes the regulating valve. The position of the swash-plate is at its most inclined and thus effects the largest delivery volume.
5% output
The conditions are fulfilled if the engine has a constantly high speed (e.g. motorway driving, and/or a low temperature). The intake pressure is relatively low and the regulating valve is open.
The position of the swash-plate is at its least inclined and thus effects the smallest delivery volume.