Complex dry vacuum pump having Roots and screw rotors

摘要

Disclosed is a complex dry vacuum pump including a root rotor and a screw rotor, which allows a process chamber of an apparatus for manufacturing a semiconductor and a display to be in a vacuum state, and discharges gaseous material and/or process by-products which are generated in a process chamber to the exterior. The complex dry vacuum pump including a root rotor and a screw rotor, includes: a housing having an interior receiving space, a suction opening on one side of the housing, and a discharge opening on the other side of the housing; first and second root rotors which are located in the interior receiving space of the housing and are the first and second root rotors being installed in such a manner as to be engaged with each other; first and second screw rotors which are located in the interior receiving space of the housing and are installed in such a manner as to be engaged with each other adjacent to the first and second root rotors; first and second power transmission shafts extending through each center of the first and second root rotors and the first and second screw rotors; first and second gears connected with the first and second power transmission shafts, respectively, while being engaged with each other; and a motor having a rotor connected with the first power transmission shaft in such a manner that the rotator can be rotated in an interior of a stator, the stator having a coil wound in the stator and being included in an interior of a case, wherein the first and second root rotors include three lobes, respectively, and molding material is molded in the stator so as to protect the coil from various by-products flowing in the interior of the housing. As mentioned above, the complex dry vacuum pump including a root rotor and a screw rotor according to the present invention, can keep high gas compression transfer efficiency so as to form a vacuum of a process chamber of an apparatus for manufacturing a semiconductor and a display or keep high gas compression transfer efficiency when gaseous material and/or process by-products, which are generated in the process chamber, are discharged. Furthermore, balance between the root rotor and the screw rotor can be kept so as to prevent vibration and noise which are generated in the vacuum pump, and molding material is molded so as to allow a stator coil to be separated and prevent various by-products from flowing from the vacuum pump. Therefore, there is no difficulty in being assembled or manufactured, and loss of power of a motor can be prevented, thereby providing a high efficiency motor.