US 11,939,891 B2
Internal combustion engine with camshaft valve phase variation device
Walter Mariotti, Pontedara (IT)
Assigned to PIAGGIO & C. S.P.A., Pontedara (IT)
Appl. No. 17/641,727
Filed by PIAGGIO & C. S.P.A., Pontedera (IT)
PCT Filed Sep. 11, 2020, PCT No. PCT/IB2020/058451
§ 371(c)(1), (2) Date Mar. 9, 2022,
PCT Pub. No. WO2021/048801, PCT Pub. Date Mar. 18, 2021.
Claims priority of application No. 102019000016271 (IT), filed on Sep. 13, 2019.
Prior Publication US 2022/0298932 A1, Sep. 22, 2022
Int. Cl. F01L 1/344 (2006.01); F01L 1/02 (2006.01); F01L 1/047 (2006.01); F01L 1/053 (2006.01); F01L 1/26 (2006.01); F02D 13/02 (2006.01)
CPC F01L 1/344 (2013.01) [F01L 1/02 (2013.01); F01L 1/022 (2013.01); F01L 1/026 (2013.01); F01L 1/047 (2013.01); F01L 1/053 (2013.01); F01L 1/26 (2013.01); F02D 13/0215 (2013.01); F01L 2001/0537 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An internal combustion engine of a motor vehicle having a ridable seat, said internal combustion engine comprising: a drive shaft, a first camshaft which controls a plurality of suction valves and a second camshaft which controls a plurality of relief valves, at least a first centrifugal device for varying a timing of valves of a first one of said plurality of suction valves and said plurality of relief valves, with respect to said drive shaft, wherein said first centrifugal device comprises:
a driving disc mounted idle on one of said first camshaft and said second camshaft which controls said first one of said plurality of suction valves and said plurality of relief valves, said driving disc rotating about a rotational axis of said one of said first camshaft and said second camshaft;
a driven disc which is integral with said one of said first camshaft and said second camshaft;
a plurality of drive elements for transmitting a motion between said driving disc, and said driven disc, wherein said driving disc, said driven disc and said plurality of drive elements are configured so as to cause a relative rotation of said driven disc with respect to said driving disc when a rotational speed of said driving disc and the driven disc exceeds a predetermined threshold,
a distribution system which mechanically connects said drive shaft with said driving disc so as to cause a rotation thereof; and
a first gear which is integral with said driving disc mounted on one of the first camshaft and the second camshaft, and a second gear mounted on a second one of said first camshaft and the second camshaft so that a rotation of said second gear directly or indirectly causes the rotation of said second one of said first camshaft and said second camshaft, wherein said second gear directly meshes with said first gear so that the rotation of said driving disc causes the rotation of said second one of said first camshaft and said second camshaft which controls a second one of said plurality of suction valves and said plurality of relief valves, and in that said distribution system comprises a first distribution wheel keyed onto said drive shaft, a second distribution wheel which is integral with said driving disc, and a flexible drive element which connects the first distribution wheel and the second distribution wheel so that the rotation of said drive shaft is transferred to said driving disc.