To prevent the increase of wear and internal leakage by drawing each gear to one side and inclining each gear in a gear type fluid pump.
A drive gear 30 of an external gear and a driven gear 31 of an internal gear are arranged in a gear chamber formed in a housing H so that each both side surfaces rotatably slide with both inside surfaces of the gear chamber. Operating oil sucked from a suction passage 21 is delivered from a delivery passage 26. A spiral groove 31a for reducing a sliding resistance between the side surface of the driven gear and the inside surface of the gear chamber is formed between the outer circumference of the driven gear and the inner circumference of the gear chamber rotatably sliding with outer circumference of the driven gear. The spiral groove makes the operating oil disposed between the driven gear and the inside surface of the gear chamber which is a side where the driven gear is separated move between the driven gear and the inside surface of the gear chamber which is a side where the driven gear is pressed. A similar spiral groove 30b may be formed between the inner circumference of the drive gear and the outer circumference of a supporting member for supporting the driven gear.
| JP6887976 | Oil pump |
| JP6115817 | Positive displacement pump |
MATSUO AKIRA
SHIBAYAMA YOSHINORI
