Four-cycle engine
AssigneeKawasaki Jukogyo Kabushiki Kaisha
InventorsShinichi Tamba, Yoshiro Yamane
Life of this patent
Estimating the term…
Abstract
A gear 11 on a crankshaft 10 is made to engage with an internal gear 21 having twice the number of teeth of the gear 11, cams 22 are formed on the exterior surface of the internal gear 21, and the cams 22 are connected with valve actuating mechanisms 40 for actuating an exhaust valve 44 and an intake valve 40 to open or close. The gear 11, the internal gear 21, etc. have the function of an oil pump.
Claims8
A four-cycle engine characterized in that a gear on a crankshaft is made to engage with an internal gear having twice the number of teeth of the former gear, cams are formed on the exterior surface of the internal gear, the cams are connected with valve actuating mechanisms for actuating an exhaust valve and an intake valve to open or close, the crankshaft is supported by a crankcase cover of the engine via a first bearing and by a crankcase of the engine via a second bearing, the internal gear is sealed within and directly supported by the crankcase cover and the crankcase, and the first bearing and second bearing are positioned to directly face opposite sides of the gear such that the first bearing and second bearing support the gear and maintain a desired engagement condition between the gear and the internal gear.
A four-cycle engine comprising:
- a crankshaft positioned within a crankcase and a crankcase cover of the engine, said crankshaft including a crankshaft gear with teeth;
- a first bearing positioned between said crankshaft and the crankcase cover such that the crankcase cover supports said crankshaft via said first bearing;
- a second bearing positioned between said crankshaft and the crankcase such that the crankcase supports said crankshaft via said second bearing;
- an internal gear mechanically coupled to said crankshaft gear, said internal gear including twice the number of teeth of said crankshaft gear, said internal gear including cams on an external surface thereof, said cams being mechanically coupled to a valve actuating mechanism of the engine, said internal gear being sealed within and rotatably supported by the crankcase forming an oil pump constructed from the crankshaft gear and said internal gear;
- said first bearing and said second bearing being positioned to directly face opposing sides of said crankshaft gear such that said first and second bearings support said crankshaft gear and maintain a desired engagement condition between said crankshaft gear and said internal gear;
- a first oil route from the oil pump directing oil to the cams;
- and
- a second oil route from the oil pump directing oil to said first bearing.
A four-cycle engine comprising:
- a crankshaft including a crankshaft gear with teeth;
- an internal gearing mechanically coupled to said crankshaft gear, said internal gear including cams on an external surface thereof, the cams being mechanically coupled to a valve actuating mechanism of the engine;
- a crankcase;
- a crankcase cover;
- said crankcase rotatably forming a concavity accommodating and rotatably supporting said internal gearing, the concavity being sealed to provide an oil pump constructed from said internal gearing, the crankshaft gear, and a spacer accommodated within the concavity;
- a first bearing positioned between said crankshaft and said crankcase cover such that said crankcase cover supports said crankshaft via said first bearing;
- a second bearing positioned between said crankshaft and said crankcase such that said crankcase supports said crankshaft via said second bearing;
- said first and second bearings being positioned on opposing sides of the crankshaft gear;
- a first oil route from the oil pump directing oil to the cams;
- a second oil route from the oil pump directing oil to said first bearing;
- and
- a third oil route from the oil pump directing oil to said second bearing.
Dependencies are inferred from the claim text.