Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/02—Valve drive
  • F01L1/026—Gear drive
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/02—Valve drive
  • F01L1/022—Chain drive
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B75/00—Other engines
  • F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
  • F02B75/18—Multi-cylinder engines
  • F02B75/24—Multi-cylinder engines with cylinders arranged oppositely relative to main shaft and of "flat" type
  • F02B75/243—Multi-cylinder engines with cylinders arranged oppositely relative to main shaft and of "flat" type with only one crankshaft of the "boxer" type, e.g. all connecting rods attached to separate crankshaft bearings
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
  • F01B1/00—Reciprocating-piston machines or engines characterised by number or relative disposition of cylinders or by being built-up from separate cylinder-crankcase elements
  • F01B1/08—Reciprocating-piston machines or engines characterised by number or relative disposition of cylinders or by being built-up from separate cylinder-crankcase elements with cylinders arranged oppositely relative to main shaft and of "flat" type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
  • F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
  • F01L1/02—Valve drive
  • F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
  • F01L1/047—Camshafts
  • F01L1/053—Camshafts overhead type
  • F01L2001/0537—Double overhead camshafts [DOHC]
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B75/00—Other engines
  • F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
  • F02B75/18—Multi-cylinder engines
  • F02B2075/1804—Number of cylinders
  • F02B2075/1808—Number of cylinders two
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B75/00—Other engines
  • F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
  • F02B75/18—Multi-cylinder engines
  • F02B75/24—Multi-cylinder engines with cylinders arranged oppositely relative to main shaft and of "flat" type

Definitions

• the present invention relates to the field of twin-cylinder engines, in particular flat-twin-cylinder engines with a camshaft housed in the cylinder head.
• Each engine-engine comprises the cylinder-piston-cylinder head assembly as well as the drive of the distribution.
• Each of these shafts drives the exhaust camshaft by a conical torque.
• Another shaft perpendicular to the intermediate axis and to the axis of the crankshaft, drives the intake cam shaft.
• British Patent GB2392476 describes another example of a multicylinder engine comprising a distribution in the median plane of the cylinders. This solution is incompatible with a two-cylinder engine.
• European Patent EP1717425 discloses an internal combustion engine having several rows of V cylinders, with a mechanism for driving the valves by two shafts.
• the first idler shaft is intended to drive the camshaft of the valves of the first row, by a first belt.
• the second crazy shaft drives the camshaft of the valves of the second row by a second belt.
• This mixed cam drive system allows the cylinder heads to be shorter and more compact.
• An intermediate shaft is driven by the gear crankshaft.
• a chain connects the intermediate shaft to the double gear housed in the cylinder head which in turn drives the camshafts.
• the chains receive guide pads with tensioner.
• the crankshaft drives an intermediate balancing shaft on which are taken the two gears (on both sides of the shaft because to have identical high-engine parts - cylinder, cylinder-, they must be mounted upside down for the rear cylinder) of the distribution,
• the camshafts must rotate at half the speed of the crankshaft. It comes out, with a chain drive, a camshaft sprocket at the head of a diameter double that integral with the crankshaft.
• the diameter of the crankshaft pinion is directly related to the inside diameter of the bearings (pins).
• the architecture includes a cascade of gables. It is quite heavy and complex to mount because it is necessary to adjust the play between pinion taking into account the crushing of all joints ...
• the sprockets can therefore be much smaller than a traditional sprocket.
• the camshaft gears and sprockets of the primary transmission are in two parts with a spring to eliminate play and reduce mechanical noise
• Suzuki has installed a tensioner with a double-step locking screw (left and right on the clamping surface) that keeps the tensioner compressed for mounting.
• the reduced stroke also reduces the height of the cylinders and increases the compactness of the block.
• the object of the present invention is to overcome these drawbacks by proposing, in its most general sense, a two-cylinder engine comprising two separate yokes each having at least one camshaft, the engine further comprising two drive means ensuring the torque transmission between the crankshaft on the one hand and one of the cam shafts on the other hand, characterized in that it comprises a primary stage comprising two counter-rotating shafts, driven by said crankshaft and each driving the crankshaft; one of said transmission means, said two transmission means being made of identical mechanical components.
• each of said drive means has a median longitudinal plane located, relative to the median plane of the engine, opposite the longitudinal plane passing through the crank pin of the engine comprising the cylinder head considered.
• said primary stage comprises a pinion gear driven by a pinion integral with the crankshaft, said idler gear driving a first distribution shaft, the second distribution comprising a pinion driven by a pinion integral with said first distribution shaft.
• each of said transmission means comprises a pinion integral with the distribution shaft, a distribution chain, at least one camshaft driven by a pinion, as well as tensioning means of said chain, said components being identical for each other. both of said dispensing means.
• At least one of said distribution shafts further drives an oil pump.
• At least one of said distribution shafts further causes a water pump.
• the primary stage provides a reduction with a ratio 1 / N
• said drive means provides a reduction with a ratio 1 / M, with N between 1.5 and 2.5 the reduction ratio overall being 1/2.
• the axes of symmetry of said yokes are parallel.
• FIG. 1 represents a three-quarter front view of an engine according to the invention
• FIG. 2 represents a schematic view from above of said engine
• FIG. 3 shows a schematic front view of said engine.
• the engine according to the invention comprises in known manner a high-engine front (1) and high-engine rear (2).
• the high-motors (1, 2) are aligned, to form a twin-cylinder architecture flat inclined at an angle of 25 ° relative to the horizontal axis.
• the connecting rods (5, 6) are offset laterally, symmetrically with respect to the median longitudinal plane of the engine. They support the pistons (7, 8).
• Each high engine (1, 2) comprises an exhaust cam shaft (9, 9 ') and an intake cam shaft (10, 10').
• These cam shafts (9, 10; 9 ', 10') are integral with the sprockets respectively (11, 12; 11 ', 12') driven by a chain respectively (13, 13 ').
• Each of the chains (13, 13 ') is driven upstream by a primary shaft gear (14, 14').
• the tension and the guidance are provided by a fixed pad (15, 15 ') and a movable pad (16, 16').
• the movable pad (16, 16 ') is pressed against the chain (13, 13') by a hydraulic tensioner, not shown.
• admission cam shafts 10 and 10 ' are strictly identical
• the lower engine (3) comprises a crankshaft (4) supporting a distribution sprocket (17).
• This drive gear (17) has 26 teeth. It drives a crazy gear (18) having, in the example described 36 teeth.
• This idler gear (18) itself drives the front shaft gear (19) having N teeth, in the example described 36 teeth.
• This front shaft gear (19) in turn drives the rear shaft gear (20) having the same number of teeth, in the example described 36 teeth.
• the front shaft (21) has a front driving sprocket (14) having N / 2 teeth, in the example described 18 teeth.
• the rear shaft (21 ') comprises a rear driving chain gear (14') having N / 2 teeth, in the example described 18 teeth.
• the chains (13, 13 ') wind up on the drive gears (14, 14') and drive the exhaust (11, 11 ') and intake (12, 12') camshaft gears. front and rear cylinder heads.
• Figure 2 shows a view from above.
• the engine has a longitudinal main longitudinal plane (23), vertical corresponds to the median plane of the motorcycle.
• the piston (7) and the front rod (5) mounted on a crankpin have a longitudinal median plane (24) offset laterally with respect to the longitudinal main median plane (23) by a distance N corresponding to half the thickness of the central flywheel (25) of the crankshaft (4) and the half thickness of the crankpin.
• the piston (8) and the connecting rod (6) rear mounted on a second crankpin have a longitudinal median plane (26) offset laterally, on the opposite side of the longitudinal median plane (24), relative to the longitudinal main median plane (23) d a distance N corresponding to half the thickness of the central flywheel (25) of the crankshaft (4) and the half thickness of the crankpin.
• the longitudinal median plane (27) of the front timing chain (13) is located on the opposite side of the median plane (24) relative to the main median plane (23). This positioning makes it possible to reduce the lateral bulk of the engine and to accommodate the front distribution members in the space available because of the shift of the upper engine-engine with respect to the main median plane (23).
• the longitudinal median plane (28) of the rear timing chain (13 ') is located on the opposite side of the median plane (26) relative to the main median plane (23). This positioning makes it possible to reduce the lateral bulk of the engine and to accommodate the rear distribution members in the space available because of the shift of the upper motor-rear relative to the main median plane (23).
• the counter-rotating front (21) and rear (22) shafts are configured so that the pinions (14, 14 ') are respectively in the planes (27, 28).
• the point of intersection between the axis of the front shaft (14) and the median plane (27) is symmetrical to the point of intersection between the axis of the rear shaft (14 ') and the median plane (28) relative to the center of symmetry of the lower engine defined by the intersection between the axis of the crankshaft (4) and the plane median principal (23).
• the upper front engine (1) is axially symmetrical with the upper engine (2) with respect to an axis (29) included in the main median plane (23). and passing through the axis of the crankshaft (4).
• Figure 3 shows a front view of the engine.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Valve-Gear Or Valve Arrangements (AREA)
• Devices For Conveying Motion By Means Of Endless Flexible Members (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=50639702

Family Applications (1)

Country Status (5)

Families Citing this family (3)

Family Cites Families (21)

• 2014
  • 2014-01-13 FR FR1450234A patent/FR3016402B1/fr active Active
• 2015
  • 2015-01-08 EP EP15702533.9A patent/EP3094844B1/de active Active
  • 2015-01-08 CN CN201580008727.7A patent/CN106030074A/zh active Pending
  • 2015-01-08 JP JP2016563264A patent/JP2017503968A/ja active Pending
  • 2015-01-08 WO PCT/FR2015/050027 patent/WO2015104496A1/fr not_active Ceased

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