High pvd coating machine, coating machine is currently the most widely used equipment for making vacuum conditions. Its related components and components: mechanical pump, booster pump, oil diffusion pump, condensation pump, vacuum measurement system.The following is a detailed introduction to the composition and working principle of each part.
  1. Vacuum main body - vacuum chamber
       According to the different requirements of the processed products, the size of the vacuum chamber is also different. At present, the most widely used ones have diameters of 1.3M, 0.9M, 1.5M, 1.8M, etc. The chamber is made of stainless steel, and it is required to be rust-free and solid. There are connection valves in each part of the vacuum chamber, which are used to connect the pumps.
       2. Auxiliary extraction system
       This exhaust system is composed of "diffusion pump + mechanical pump + Roots pump + cryogenic cold trap + polycold"
       The exhaust process is as follows: the mechanical pump first pumps the vacuum chamber to a low vacuum state less than about 2.0*10-2PA, which provides the premise for the subsequent vacuuming of the diffusion pump, and then when the diffusion pump pumps the vacuum chamber, the mechanical pump cooperates with oil diffusion The pumps are connected in series to complete the pumping action in this way.
       The exhaust system is an important part of the vacuum system of the coating machine. It mainly consists of three parts: mechanical pump, booster pump (mainly introduces Roots pump), and oil diffusion pump.
       Mechanical pump: also called backing pump, mechanical pump is the most widely used low vacuum pump. It uses oil to maintain the sealing effect and relies on mechanical methods to continuously change the volume of the suction cavity in the pump, so that the pumped container The volume of the gas inside is constantly expanding to create a vacuum.
       There are many kinds of mechanical pumps, commonly used four types are slide valve type (this is mainly used in large equipment), piston reciprocating type, fixed vane type and rotary vane type (this is currently the most widely used, this article mainly introduces).
       pvd coating machine mechanical pumps are often used to extract dry air, but cannot extract high oxygen content, explosive and corrosive gases, mechanical pumps are generally used to extract permanent gases, but for water vapor Doesn't work well, so it doesn't pump moisture. The main components in the rotary vane pump are stator, rotor, shrapnel, etc. The rotor is inside the stator but has a different axis from the stator, like two inscribed circles. There are two shrapnels in the rotor slot, and a spring in the middle of the two shrapnels. It is ensured that the shrapnel is tightly attached to the inner wall of the stator.