Cam Cam Benz variable valve lift system Camtronic

With the the automotive environmental tide and there is a growing focus on small-displacement, the overall trend of the turbocharged engine, Mercedes-Benz has finally in 2012, adding in its M270 engine variable valve lift technology: Camtronic. The aspect of the system in the working principle and many other depot variable valve lift technology similar, but Benz system more compact structure, and system operation is relatively more simple. This is undoubtedly a more suitable "land is" gold "engine compartment space and also have a large degree of freedom in the compact car's engine layout.

Camtronic variable valve lift technology has the following characteristics:

1, a variable stroke:

Market third-generation A-Class, a total of three models of gasoline and 4 diesel engine, a total of seven engine version. All gasoline engine equipped with turbocharging and direct injection technology, output horsepower to 112hp, 156hp and 211hp, torque range from 200-350Nm.

Less powerful 1.6L gasoline engine with an additional double-clutch gearbox, the most horsepower gasoline engine is still mounted on the A250. The generation of A-Class cancel the configuration of the torque converter, Benz plans in their new 1.6L engine is put to use the two-stage throttle valve, and the intake side of the valve lift mechanism, instead of the previous fully variable valve lift technology. By a servo motor (actuator) mobile camshaft two slide cam member, so that by switching different cam, different cam angle control different valve opening degree to meet the intake air requirement

2, a three-stage camshaft design:

Camshaft itself consists of three parts: an actuator and two cam side movable block pushes on the valve movement. Two movable blocks, respectively, at both ends of the actuator, a control valve of the twelve cylinders and another one to control the three-cylinder valve. The cam surface of a width of only half of the conventional cam, the roller rocker also responsible for driving the valve open, so the width of the space required is the same as the same with the previous.
3, more energy efficient:

Why make such a big effort to re-develop a system? Other manufacturers have launched fully variable valve technology for a long period of time, a BMW, for example, as early as in 2001, has variable valve system loaded on its 4-cylinder engine. Mercedes advantage of this system lies in its structure is not only simple, but also cost savings. On the other hand, Mercedes-Benz, said that the 10% increase in economic Camtronic system in part load case than before the traditional system. NEDC test, the engine using Camtronic system than before the old variable valve liter the process engine emissions decreased 3.5%. In the case of low-speed and light load, Camtronic open only a small valve, the closing time of the intake valve is earlier, the intake air throttle valve, even at low load conditions to maintain a full-open state, so to avoid the typical throttling losses. The system is such that the maximum torque under the speed provided by the turbine can be obtained even if the output timing of the low-twist. Need high power output, the valve is opened to the maximum, need according to load, throttle back to conventional control mode at the same time through the turbo supercharger value.