Cross section of a compressor
1 - back; 2 - suction hole; 3 - gasket on the back; 4 - valve plate; 5 - reed plate; 6 - clutch winding; 7 - pulley; 8 - drive disk; 9 - pulley bearing; 10 - shaft key; 11 - shaft nut; 12 - front gasket holder; 13 - front gasket; 14 - sealing ring of the front gasket; 15 - front part; 16 - compressor control valve; 17 - high pressure bypass valve.
Compressors of various types are used on cars. The basic methods for overhauling all compressors remain the same.
When carrying out maintenance, do not allow contamination and foreign objects to fall on / or inside the parts and system of the compressor. Before any kind of repair or before removing the compressor, it is necessary to wipe the compressor connectors and its external part. All parts of the compressor must be kept clean at all times, and those parts to be reinstalled must be wiped with trichloroethane, thinner gasoline, kerosene, or similar solvent, and then dried with dry air. For wiping use only matter without lint and fluff.
When you remove the compressor from the machine for maintenance, the remaining oil in the compressor must be pumped out and measured. It will then have to be discarded and new 525 refrigeration oil added to the compressor.
Description of work
The main mechanism of the compressor is a variable angle swashplate which has five cylinders arranged along the axis. Compressor flow is controlled by a bellows-operated control valve located at the rear of the compressor, where its suction pressure is measured. The swashplate angle and the compressor flow are adjusted depending on the pressure difference between the crankcase and the intake manifold. If the conditioned air consumption is high, the suction pressure will be above the set point, the valve will bleed the gas from the crankcase to the manifold, there will be no pressure difference between the crankcase and the intake manifold, and then the compressor displacement will be maximum. If the load on the air conditioning system is lower and the suction pressure reaches the set point, then the exhaust gas will go through the valve into the engine crankcase and close the passage from the crankcase to the suction chamber.
The angle of inclination of the disk depends on the force balance on the five pistons. A slight increase in the pressure difference in the crankcase and in the intake manifold creates a resultant force on the pistons, which sets them in motion around the axis of rotation of the inclined disk, which reduces the angle of the disk. The compressor is equipped with a unique lubrication system. The oil flowing out of the crankcase goes through a rotating swash plate to lubricate the plate bearing. During rotation, part of the oil is separated from the general flow and again sent to the crankcase, where the compressor mechanism is lubricated.
Oil may accumulate in the crankcase. Therefore, when replacing a compressor, it is important to pump oil from the crankcase of the old compressor through the drain hole and measure (throw away the old oil).
All replacement compressors have crankcases filled with oil; this oil must be recovered and stored. Then change the oil in the same amount that was measured on the old compressor.