Similarly to rotary vane and rotary lobe pumps, the claw pumps are based on a static compression system. Within the compressor housing (C) two rotors (E, F) turn in opposite directions without contact observing a very tight clearance. They are synchronized by a precision gear. The gas is sucked into the compression chamber once the claw moves over the suction connection (B) and the axial suction channel inlet (D). The gas is moved from the suction side to the pressure side by the rotors rotation, where it is compressed by the volume reduction between rotors until the lower rotor uncover the discharge channel (G). The pre-compressed gas is discharged by the pressure connection (H). The heat generated by the vacuum process is removed by cooling air which is sucked in between the pump housing (C) and a silencing cover (A).
*This description does not take into account the approach of each manufacturer to the technology, but represents a generalized description that tries to include the basic operating principle.