Valve train mainly for camshaft and its drive
by：Jet Power 2020-11-28
Valve train mainly for camshaft and its drive. Including the servo arm, push rod, rocker arm shaft and t clamp, etc. Valve drive can ensure the open and close according to certain distribution phase intake valve and exhaust valve, and ensure adequate opening. 1. The structure of the camshaft camshaft is one of the key parts of a direct impact on engine performance. In recent years, the company through the improvements on the camshaft, make the diesel engine performance has improved a leap, formed the current 6 bt series diesel engine camshaft in two forms, namely big camshaft and small two kinds of CAM shaft. Large CAM shaft journal for 63. 5 mm, small CAM shaft journal is 5. 8mm。 Camshaft and divided into Ⅰ due to some changes in the structure of diesel engine, Ⅱ, Ⅲ, Ⅳ, Ⅴ, Ⅵ type, the current domestic Ⅰ type. Due to the large camshaft injection duration is shorter, higher injection pressure, burning more completely, can improve combustion efficiency, reduce exhaust temperature and can eliminate the CAM shaft bending deformation, therefore in recent years the production of 6 bt series diesel engine has fully adopted the camshaft. China's production of chongqing K6 series diesel engine camshaft in the cylinder block at the top. This makes the push rod is the shorter of the 6 bt series diesel engine, light weight, improves the rigidity of valve-train, reduce the inertia. 6 bt series diesel engine camshaft is 7 journal of whole support structure. The camshaft with a total of 18 CAM, there are six composed of pieces of circular arc of the injector drive CAM, 12 control inlet and exhaust valves open and close the peach CAM, the front of the CAM shaft is equipped with timing gear, direct and crankshaft timing gear, clearance of 0. 10 to 0. 40mm。 The camshaft thrust device has two kinds, one kind is thrust plate, axial driving to 0. 03 ~ 0. 13mm； The other is a camshaft bearings, clearance of 0. 20 ~ 0. 33mm。 Camshaft there are seven axle strength, each CAM shaft strength have ring and cylinder wall of the middle oil think, engine oil from oil duct to lubrication camshaft. CAM shaft bushing diameter is the same, but there are two kinds of wall thickness. Is a kind of thin wall bushing, wall thickness 1. 59mm； The other is a thick wall bushing ( Large camshaft models with thick wall bushing) And 2 wall thickness. 38mm。 The camshaft ( Big camshaft type) Seven bushing with three kinds of specifications, as shown in figure 3 - 16. On the seventh bushing has a positioning hole, when installation should be down, on the oil hole on cylinder body.