To enhance airtightness in a pump chamber of a Roots pump.
A rotor 23 has a movable wall 33 on one opening side of through holes 291, 301, and a movable wall 34 on the other opening side of the through holes 291, 301. Fitting protrusion parts 371 of the movable walls 33, 34 are slidably fitted into the through hole 291, and fitting protrusion parts 372 are slidably fitted into the through hole 301. The movable walls 33, 34 are slidable in a direction of an axis 171 of a rotating shaft 17. Compression springs 41, 42 of coil shape are held in the through holes 291, 301. The compression springs 41, 42 bring an end face 373 of the movable wall 33 into pressure contact with a chamber forming end face 163 of an end wall 16, and bring an end face 373 of the movable wall 34 into pressure contact with a chamber forming end face 123 of a front housing 12.
| JP2001304161 | IMPROVED VACUUM PUMP |
| JP2591722 | [Name of device] Blower device |
KAGAMI MASANAO
YAMADA KAZUO
FUJII TOSHIRO
Makoto Onda
Next Patent: DRIVE SOURCE PROVIDED WITH COMPRESSION MECHANISM COMPRESSING FLUID BY USING OUTPUT OF ELECTRIC MOTOR...