Ô tô Camry 3.5Q - Phần 1 Phần 1 (Tài liệu bằng tiếng anh) gồm: - Kết cấu thân xe - Kết cấu phần điện - CHASSIS - Kích thước xe - Động cơ xe
EGENGINE– 2GR-FE ENGINE285EG18Intake CamshaftsExhaust CamshaftsTiming Chain (Primary)Timing Chain (Secondary)ValveValve Spring SheetValve SpringValve Spring RetainerRoller Rocker ArmHydraulicLash AdjusterValve Guide BushEG-73JVALVE MECHANISM1.GeneralDEach cylinder of this engine has 2 intake valves and 2 exhaust valves. Intake and exhaust efficiency isincreased due to the larger total port areas.DThis engine uses roller rocker arms with built-in needle bearings. This reduces the friction that occursbetween the cams and the areas (roller rocker arms) that push the valves down, thus improving fueleconomy.DA hydraulic lash adjuster, which maintains a constant zero valve clearance through the use of oil pressureand spring force, is used.DThe intake camshafts are driven by the crankshaft via the primary timing chain. The exhaust camshaftsare driven by the intake camshaft of the respective bank via the secondary timing chain.DThis engine uses a dual VVT-i (Variable Valve Timing-intelligent) system, which controls the intake andexhaust camshafts to provide optimal valve timing according to driving conditions. With this adoption,lower fuel consumption, higher engine performance, and fewer exhaust emissions have been achieved.For details of dual VVT-i control, refer to page EG-110. ENGINE – 2GR-FE ENGINE285EG19VVT-i ControllersNo.2 Camshaft (Exhaust)No.1 Camshaft (Intake)No.3 Camshaft (Intake)Indented R portion of cam (Profile)Cam with indented RNo.4 Camshaft (Exhaust)VVT-i ControllersTiming RotorVVT-i ControllersTiming Rotor285EG20Chain Tensioner (Secondary)Chain Tensioner (Primary)BallBallSpringPlungerSecondaryChainChain Tensioner (Secondary)Chain Tensioner (Secondary)SecondaryChainIdle SprocketChainDamperPrimaryChainTiming Chain Oil JetChainSlipperMain SpringSpringPlungerCamCam SpringEG-742. CamshaftD The camshafts are made of cast iron alloy.D An oil passage is provided on the intake and exhaust camshaft in order to supply engine oil to the VVT-isystem.D A VVT-i controller has been installed on the front of the intake and exhaust camshaft to vary the timingof the intake and exhaust valves.D Together with the use of the roller rocker arm, the cam profile has been designed with an indented R(radius). This results in increased valve lift when the valve begins to open and finishes closing, helpingto achieve enhanced output performance.3. Timing Chain and Chain TensionerD Both the primary and secondary timing chains use roller chains with a pitch of 9.525 mm (0.375 in.).D The timing chain is lubricated by an oil jet.D The primary chain uses one timing chain tensioner and each of the secondary chains for the right and leftbanks uses one timing chain tensioner.D Both the primary and secondary chain tensioners use a spring and oil pressure to maintain proper chaintension at all times. They suppress noise generated by the timing chains.D The chain tensioner for the primary chain is the ratchet type with a non-return mechanism. EGENGINE – 2GR-FE ENGINE285EG21Water PumpWater Pump GasketTiming Chain CoverWater Pump Swirl ChamberView from Front SideTiming Chain CoverOil Pump HousingOil Pump ChamberOil Pump RotorView from Back Side285EG22PlungerOilPassageCheck BallCheck Ball SpringPlunger SpringOilPassageHydraulicLash AdjusterCamRoller Rocker ArmService TipValve clearance adjustment is not necessary because a hydraulic lash adjuster is used in this model.EG-754. Timing Chain CoverThe timing chain cover has an integrated construction consisting of the cooling system (water pump andwater passage) and the lubrication system (oil pump and oil passage). Thus, the number of parts has beenreduced to reduce weight.5. Hydraulic Lash AdjusterD The hydraulic lash adjuster, which is located at the fulcrum of the roller rocker arm, consists primarily ofa plunger, plunger spring, check ball, and check ball spring.D The engine oil that is supplied by the cylinder head and the built-in spring actuate the hydraulic lashadjuster. The oil pressure and the spring force that act on the plunger push the roller rocker arm againstthe cam, in order to adjust the valve clearance that is created during the opening and closing of the valve.As a result, engine noise is reduced. . of dual VVT-i control, refer to page EG -1 1 0. ENGINE – 2GR-FE ENGINE285EG19VVT-i ControllersNo.2 Camshaft (Exhaust)No .1 Camshaft (Intake)No .3 Camshaft (Intake)Indented. Spring RetainerRoller Rocker ArmHydraulicLash AdjusterValve Guide BushEG-73JVALVE MECHANISM1.GeneralDEach cylinder of this engine has 2 intake valves and 2 exhaust