Internal combustion engine with variable flow rate oil pump apparatus, and motorcycle incorporating same

An internal combustion engine comprising:

• a crankcase;
• a crankshaft disposed in said crankcase;
• a variable flow rate oil pump apparatus including a pump body having a plurality of oil pumps arranged on a shared drive shaft,
• said plurality of pumps comprising coaxially arranged first and second oil pumps;
• said first and second oil pumps having pump rotors interlockingly arranged with said crankshaft for rotation thereof;
• and
• a rod-shaped oil passage switching valve arranged in discharge ports of said first and second oil pumps in said pump body;
• wherein said oil passage switching valve and said shared drive shaft of said first and second oil pumps are arranged such that an axial direction of said oil passage switching valve and an axial direction of the drive shaft of said first and second oil pumps are arranged parallel to an axial direction of said crankshaft;
• and
• wherein said first and second oil pumps and said oil passage switching valve are arranged so as to overlap each other in the axial direction of said crankshaft.

A motorcycle comprising an internal combustion engine, said internal combustion engine comprising:

• a crankcase;
• a crankshaft disposed in said crankcase;
• a variable flow rate oil pump apparatus comprising first and second oil pumps having pump rotors interlockingly arranged with said crankshaft for rotation thereof;
• a rod-shaped oil passage switching valve arranged in discharge ports of said first and second oil pumps;
• wherein said oil passage switching valve and said drive shaft of said first and second oil pumps are arranged such that an axial direction of said oil passage switching valve and an axial direction of the drive shaft of said first and second oil pumps are arranged parallel to an axial direction of said crankshaft;
• and
• wherein said first and second oil pumps and said oil passage switching valve are arranged so as to overlap each other in the axial direction of said crankshaft.