(1) The overall structure of the pump

The layout structure of the pump body of the vacuum pump determines the overall structure of the pump.

The vertical structure of the inlet and outlet is set horizontally, and it is more convenient to assemble and connect the pipeline.However, the center of gravity of the pump is high, and the stability is poor during high - speed operation, so this type is mostly used

for small pumps.

The inlet of the horizontal pump is on the top, and the exhaust is on the bottom.Sometimes in order to facilitate the installation and connection of the vacuum system pipes, the exhaust port can be connected from the horizontal direction, that is, the inlet and exhaust directions are perpendicular to each other.At this time, the exhaust port can be opened from the left or in two directions.Except

for connecting one end of the exhaust pipe, the other end is blocked or connected to the bypass valve.This pump has a low center of gravity and good stability at high speeds.Generally, large and medium - sized pumps adopt this structure.

The two rotor shafts of the pump are installed perpendicular to the horizontal plane.The assembly gap of this structure is easy to control, the rotor is easy to assemble, and the pump occupies a small area.However, the center of gravity of the pump is high and the gears are inconvenient to disassemble, and the lubrication mechanism is relatively complicated.

(2) Pump transmission mode

The two rotors of the vacuum pump are operated relatively synchronously through a pair of high - precision gears.The driving shaft is connected to the motor through a coupling.There are two main types of transmission structure layout: one is that the motor and gear are placed on the same side of the rotor as shown in the figure.The driven rotor is directly driven by the gear on the motor end, so that the torsional deformation of the active rotor shaft is small, the gap between the two rotors will not change due to the large torsional deformation of the drive shaft, so the gap between the rotors is running Even during the process.The biggest shortcomings of this transmission method are: a.There are three bearings on the driving shaft, which increases the difficulty of processing and assembly of the pump, and it is also inconvenient to disassemble and adjust the gear;

b.The overall structure is uneven, and the center of gravity of the pump is biased toward the motor and gear Box side.