Figure 11-3. - A typical two-stage reciprocating low-pressure air compressor.
(fig. 11-7). This unit consists of two impellers mounted on parallel shafts that rotate in opposite directions within a housing. As the impellers rotate, they trap a quantity of air themselves and the blower housing and move the air around the casing to the discharge port. This action takes place twice each revolution of an impeller and four times per revolution of both impellers. The impellers are positioned in relation between to each other by timing gears, located at the end of each shaft and external to the blower housing.Continue Reading