Pneumatic pump dealers, two rotors through a pair of high-precision gear relative synchronous operation, to achieve the double rotation of the vacuum pump. The main shaft and the motor are connected by a coupling. There are mainly two kinds of driving structure: the motor and gear are placed on the same side of the rotor, and the gear at the end of the motor directly drives the rotor, so that when the torsional deformation of the rotor spindle is small.

The gap between the two rotors will not change due to the large torsional deformation of the main shaft, so that the gap between the rotor and the main shaft can run evenly. There are three bearings on the driving shaft, which makes it difficult to process and assemble the pump. Moreover, it is not convenient to disassemble and adjust the gear; b. The overall structure is uneven, and the center of gravity of the pump is shifted to one side of the motor and gearbox.

In the vacuum pump, the overall structure of the pump is determined by the arrangement of the pump body. The air inlet and outlet of vertical structure are set horizontally, which makes the installation of connecting pipes more convenient. However, due to its high center of gravity and poor stability at high speed, the pump is mostly used for small pumps. The air inlet of the horizontal pump is above and the air outlet is below. In the vacuum system, sometimes for the convenience of installation and connection, the exhaust port can be connected from the horizontal direction.

That is to say, the intake and exhaust directions are perpendicular to each other. At this time, the exhaust port can be opened from the left and right directions. In addition to connecting one end of the exhaust pipe, the other end can block or cut off the bypass valve. The pump has low center of gravity, fast working speed and good stability. Usually large and small pumps use this structure. The two pump rotor shafts are installed perpendicular to the horizontal plane.

The installation clearance of the structure is easy to control, the rotor is easy to install, and the occupied space of the pump is small. However, the center of gravity of the pump is high, the disassembly and assembly of the gear is inconvenient, and the lubrication mechanism is more complex. The rotor has good geometric symmetry, so the vibration is small and the operation is stable. There are gaps between the rotors and between the rotor and the casing, so there is no need for lubrication, and the friction loss is small, which can greatly reduce the transmission power and achieve the purpose of high-speed operation.