Theory of Operation

The V5 is a variable displacement compressor that can match the automotive air conditioning demand under all conditions without cycling. The basic compressor mechanism is a variable angle wobble-plate with five axially oriented cylinders. The center of control of the compressor displacement is a bellows actuated control valve located in the rear head of the compressor that senses compressor suction pressure. The wobble-plate angle and compressor displacement are controlled by the crankcase-suction pressure differential. When the A/C capacity demand is high, the suction pressure will be above the control point; the valve will maintain a bleed from crankcase to suction; no crankcase-suction pressure differential; and the compressor will have maximum displacement. Then the A/C capacity demand is lower and the suction pressure reaches the control point, the valve will bleed discharge gas into the crankcase and close off a passage from the crankcase to the suction plenum. The angle of the wobble-plate is controlled by a force balance on the five pistons. A slight elevation of the crankcase-suction pressure differential creates total force on the pistons resulting in a movement about the wobble-plate pivot pin that reduces the plate angle.

The compressor has a unique lubrication system. The crankcase-suction bleed is routed through the rotating wobble-plate for lubrication of the wobble-plate bearing. The rotation acts as an oil separator, which removes some of the oil from the crankcase-suction bleed, rerouting it to the crankcase where it can lubricate the compressor mechanism.

Up to 4 oz. of oil can collect in the crankcase. Therefore, it is important when replacing a compressor that the oil in the old compressor crankcase be drained thru the drain plug and measured (discard after recording amount).

All replacement compressors will be shipped with 8 oz. of oil in the crankcase, the oil must be drained and retained. Then replace the oil in the same amount as previously recorded from the old compressor.