A rotary vane vacuum pump can be an oil-sealed rotary displacement pump. The pumping program consists of a housing (1), an eccentrically installed 
rotor (2), vanes that move radially under springtime pressure (3) and the inlet and store (4). … The Rotor moves with the aid of a motor attached to it.
Uses. Vane pumps are commonly used as high-pressure hydraulic pumps and in automobiles, including supercharging, power-steering, air conditioning and automatic-transmitting pumps. Pumps for mid-range pressures consist of applications such as carbonators for fountain soft-drink dispensers and espresso coffee machines.
The easiest vane pump has a circular rotor rotating inside a bigger circular cavity. The centers of the two circles are offset, leading to eccentricity. … The action of the vane drives out the same volume of liquid with each rotation. Multistage rotary-vane vacuum pumps can attain pressures only 10 mbar (0.0001 Pa).