Claw Rotor A dry mechanical vacuum pump (also referred to as a claw pump) has two conjugate claw rotors in the pump housing. Like Roots vacuum pumps, the rotor is driven by a pair of synchronized, high-precision gears that rotate and hold the phase. The rotor profile is composed of six sections of cycloidal and circular arcs. There is no gap between the rotors and between the rotors and the pump casing, leaving a slight gap. Gas inlet and exhaust ports are located in the end face of the pump housing, respectively, by the two rotor end face periodic periodic opening and closing valve with the regulatory role. Claw rotor dry mechanical vacuum pump machine type is divided into vertical and horizontal two. The horizontal structure is represented by DP80 type mechanical vacuum pump developed by British Edward Company with a Roots rotor plus three-stage claw rotors. The Roots rotor is a high vacuum suction stage and the claw rotor is a compression exhaust stage so arranged to achieve a large pumping rate at low inlet pressure. The ultimate pressure up to 1Pa below. This structure of the pump is characterized by low center of gravity machine, all levels of rotor and the gap between the separator easy to adjust. In order to obtain a greater pumping speed at low pressure, the pump Roots suction level should be done 50% larger than the claw exhaust level. In order to prevent the pump from generating "overpressure" between the groups during the rough pumping, a larger transmission space is provided between the roots and the middle claw-type stage as a pressure buffer space. In addition you can install interstage pressure relief valve to ensure reliable work. In order to assist in the extraction of water vapor, a gas ballast valve is provided at the pump's discharge level. Pump drive type and Roots vacuum pump the same. Through the above analysis we can see that the claw rotor dry mechanical vacuum pump has the advantages of Roots vacuum pump and rotary vane vacuum pump.