Design of a Liquid Pump with New Claw Rotors

This thesis develops a new type of liquid pump by using new claw rotors. Firstly, a patented new claw rotor is presented. The rotor profile is defined by parameters such as rotor radius, pitch radius, claw depth, contact angle and number of claws. Then, a new type of liquid pump using this new claw rotor is designed. Main components of the claw pump include a pair of claw rotors with five claws for transferring the liquid, a pair of gears for maintaining the two rotors with the same rotational speeds but with different directions, and a supporting housing for both the rotors and gears. Performances of the claw pump, such as specific flow rate, leakage and power consumption, can be predicted from design parameters of the rotor profile. Performances of the claw pump are also compared with those of lobe pumps and gear pumps to show the design advantages of claw pumps over the other two pumps. Finally, a prototype of the claw pump is manufactured, and performances, including flow rate, pressure head, rotational speed and power consumption, are measured. Performances of two similar traditional centrifugal liquid pumps and a gear pump are also measured for comparison with those of the claw pump. From the measured results, it shows that the proposed new claw pump has better performances than those of the traditional centrifugal pumps and gear pumps.