US 12,078,172 B2
Multi-stage screw compressor
Takeshi Tsuchiya, Tokyo (JP); Kotaro Chiba, Tokyo (JP); Toshiaki Yabe, Tokyo (JP); and Shigeyuki Yorikane, Tokyo (JP)
Assigned to Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
Appl. No. 18/278,431
Filed by Hitachi Industrial Equipment Systems Co., Ltd., Tokyo (JP)
PCT Filed Mar. 2, 2022, PCT No. PCT/JP2022/008872
§ 371(c)(1), (2) Date Aug. 23, 2023,
PCT Pub. No. WO2022/202163, PCT Pub. Date Sep. 29, 2022.
Claims priority of application No. 2021-048480 (JP), filed on Mar. 23, 2021.
Prior Publication US 2024/0141896 A1, May 2, 2024
Int. Cl. F04C 23/00 (2006.01); F04C 18/08 (2006.01); F04C 18/16 (2006.01); F25B 1/047 (2006.01)
CPC F04C 23/001 (2013.01) [F04C 18/08 (2013.01); F04C 18/084 (2013.01); F04C 18/16 (2013.01); F25B 1/047 (2013.01); F04C 2240/20 (2013.01); F05B 2260/4031 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A multi-stage screw compressor comprising:
a plurality of stages of compressor bodies that compress a gas in sequence, wherein
each stage of the plurality of stages of compressor bodies has a pair of screw rotors that are housed revolvably in a casing in a mutually meshing state,
each of the screw rotors includes a rotor lobe section, the rotor lobe section having a suction-side end face and a discharge-side end face at one end and another end in an axial direction and having a twisted lobe extending from the suction-side end face to the discharge-side end face, and
each of the screw rotors in a compressor body of at least one certain stage, excluding a compressor body of a first stage positioned at an upstream end, among the plurality of stages of compressor bodies is configured such that lead increases from a suction side in the axial direction of the rotor lobe section toward a discharge side, the lead representing a length of advance in the axial direction for each revolution of the twisted lobe.