可变气门配气相位和气门升程电子控制系统VTEC技术解析

可变气门配气相位和气门升程电子控制系统VTEC技术解析

the camshaft and rocker arms, but unlike ordinary engine is the number and control method of cam and rocker arm. Medium and low speed with a small angle of the cam, two valve timing and lift different at low speed, this time a valve lift is very small, almost do not participate in the intake process, the air intake channel basically the equivalent of two valve engine, but due to the flow direction of an intake air barrier gas cylinder center, so it can produce intake eddy current, strong for low speed, especially in the cold car conditions conducive to improving the mixture uniformity, increases the burning rate and decrease the effect of wall surface chilling effect and clearance, making the combustion more fully, thereby improving the economy, and significantly reduce HC and CO emissions; and at high speeds. Through to VTEC solenoid valve to control the hydraulic oil, so that the two intake rocker arms are connected as a whole and the intake cam from the opening of the longest and largest lift to drive the valve, this time two inlet valve according to the cam profile synchronization. Compared with the low speed operation, greatly increasing the inlet flow area and opening duration, so as to improve the power of the engine at high speed. This two kinds of entirely different performance curve of output, Honda engineers so that they are implemented in the same engine, and vividly described as "the usual soft driving" and "wartime intense driving".

But VTEC system for gas distribution phase change is still the stage, that is to say the change with gas phase only at a speed jump, but not in a speed range of continuous variable. In order to improve the performance of VTEC system, Honda constantly innovate, introduced the i-VTEC system.

Simply put, the i-VTEC system is based on VTEC, added a called VTC (Variable timing control "variable timing control device") -- a group of inlet valve camshaft timing variable control mechanisms, i.e. i-VTEC=VTEC VTC. At this point, the exhaust valve timing and overlapping time open is variable, controlled by VTC, into the VTC mechanism so that the engine can have suitable gas distribution phase in large range of speed, which improves the performance of the engine to a large extent.

A typical VTC system by the VTC actuator, VTC oil control valve, all kinds of sensors and ECU components. The VTC actuator, VTC oil control valve can generate action according to the ECU signal, the phase of inlet camshaft continuous change. VTC makes the valve overlap time more accurately, ensure the intake valve and exhaust valve, the best lap time, can improve engine power 20%.