Sliding member and oil pump
AssigneeSumitomo Electric Industries, Ltd.
InventorKatsuyoshi Kondoh
Life of this patent
Estimating the term…
Abstract
An outer rotor and an inner rotor are formed of sintered aluminum alloy. The sintered aluminum alloy contains 0.5 wt % to 11 wt % of aluminum nitride. Porosity of the sintered aluminum alloy for outer rotor is 3 vol % to 15 vol %. Porosity of the sintered aluminum alloy for inner rotor is 2 vol % to 10 vol %. Outer rotor and inner rotor are set in a pump case. A rotary driving shaft formed of steel is inserted to a through hole of inner rotor. A press fit member is inserted at a press fit surface of inner rotor and rotary driving shaft. Accordingly, sliding members formed of sintered aluminum alloy which reduces seizure and abrasive wear of the inner and outer rotors can be provided, and in addition, an oil pump of which wear and damage at the inner rotor inner diameter surface is suppressed, can be provided.
Claims25
A pair of sliding members sliding over each other, wherein one of the sliding members is formed of an aluminum alloy containing 5 wt % to 30 wt % of silicon,
- the other one of the sliding members is formed of a sintered aluminum alloy containing 0.1 wt % to 3.5 wt % of nitrogen, and
- said nitrogen exist in said sintered aluminum alloy as aluminum nitride.
An oil pump, comprising:
- a pump case;
- an outer rotor having on its inner peripheral surface teeth of which shape is based on any of trochoid curve, involute curve and hypo-cycloid curve, fixed in said pump case;
- an inner rotor to be engaged with the inner peripheral surface of said outer rotor, the inner rotor having on its outer peripheral surface teeth of which shape is based on any of trochoid curve, involute curve and hypo-cycloid curve and having a through hole at the center;
- a rotary driving shaft formed of steel inserted to said through hole;
- wherein
- said outer rotor is formed of an aluminum alloy containing 5 wt % to 30 wt % of silicon,
- said inner rotor is formed of a sintered aluminum alloy containing 0.1 wt % to 3.5 wt % of nitrogen,
- said nitrogen existing in said sintered aluminum alloy as aluminum nitride, and
- a wear resistant member is inserted at a fitting surface between said inner rotor and said rotary driving shaft formed of steel.
Dependencies are inferred from the claim text.