Initially rotary lobe blower were designed as twin lobe, two shaft gas compressors. Two parallel installed rotors with identical lobe profils are rotating inside the housing in opposite directions. As they rotate, gas is drawn into the space between each lobe and the casing where it is trapped, transported and discharged by the rotation. For each of the two lobes, this process is being repeated twice per full rotation. The disadvantage of this solution was a high pulsation at the discharge and high noise level. The developement of a three lobe system was the consequence, reducing the volume of the discharge per pulse and increasing the frequence of pulses by 30% at the same speed. So the problem of pulsation was reduced, but at the same time the volumetric efficiency was also reduced!






