To provide an electric root type pump capable of directly cooling an electric motor from inside by efficiently cooling a driving rotor to cool the electric motor from a rotor motor through a driving shaft.
The driving rotor 27 is formed with a recessed part 27d in one end surface 27c crossing the axial direction of the driving shaft 21 and facing an end wall 13b of a first housing 13, and is formed with a driving rotor inner passage 27e communicated with the recessed part 27d through the inside of the driving rotor 27 along the axial direction of the driving shaft 21. The end wall 13b is formed with a suction port 31 communicated with the recessed part 27d and for sucking hydrogen off gas into a rotor chamber 15 at a position on the same shaft with the driving shaft 21. Further, an end surface 14a of a second housing 14 is formed with a groove 50 communicating the driving rotor inner passage 27e with a driving side pump chamber P1.
KAGAMI MASANAO
KATO HIROAKI
YAMADA KAZUO
Makoto Onda
Next Patent: SCROLL COMPRESSOR AND REFRIGERATION AIR CONDITIONER