PURPOSE: To simplify a sealing structure by installing each turning shaft in two scrolls, being intercombined, housed in a pump casing, while setting up a passage, being interconnected to a sealed space between both these scrolls, in one side of these turning shafts, and interconnecting this passage to a vacuum chamber.
CONSTITUTION: In this vacuum pump, a driving scroll 9 and a driven scroll 14 with spiral bodies 9b, 14b alternated with each other are housed in an inner casing 6 locked to the inside of an outer casing 51 free of rotation. Each belt pulley is installed in a driving shaft 10 and a driven shaft 16 installed in these scrolls 9, 14, and they are interlocked and rotated by motive power of a motor 4 via belts 31, 32 or the like. In this case, an exhaust port 54 and a coolant gas supply port 55 being opened to the inside and outside of the inner casing 6 are installed in the outer casing 51. In addition, a vacuum chamber 58 provided with an inlet port 59 is installed in the outer casing 51, and this vacuum chamber 58 is interconnected to a sealed space 15 between both these scrolls 9 and 14 via a passage piercing through the driven shaft 16.
SEKIYA SHIN
NISHIDA MITSUHIRO
