Motorcycle Starter Motor Valve Timing Technology Overview
Motorcycle Starter Motor valve timing technology overview
1, valve timing technology overview
The opening and closing of the engine's intake and exhaust valves is usually indicated by the crank angle, known as the valve timing angle. From the valve timing diagram (see), it can be seen that the intake valve opens (α) and delayed off (β) during the intake air (light gray) from the top dead center to the lower punctual. When the engine is completed, the piston moves from the bottom dead center to the top dead center (dark gray), and the exhaust valve opens (γ) and delayed off (δ) in advance. When the engine is running at a very high speed, the four-stroke engine is only a few thousandths of a working stroke, and such a short time often causes the engine to enter the air, and the exhaust is not clean, resulting in a power drop.
Therefore, in order to solve this problem, the general engine are used to extend the intake and exhaust valve opening time, increase the gas out of the capacity to improve the inlet and exhaust valve working conditions, in order to improve the performance of the engine.
Technology is in recent years has been gradually applied to modern cars on a new technology, the use of intelligent variable valve timing technology engine at low speed, the valve overlap angle is relatively small, so that the valve ahead of the opening and delay off The time is longer; then in the case of high speed, the valve overlap angle becomes larger, so that the valve ahead of the opening and delay the closure of the time shortened, so that the engine in all conditions can get sufficient intake, thereby increasing The engine work efficiency, but also to the engine in the low turn when there is sufficient torque output, high speed can have a more powerful power output, so that the engine torque output more stable, more linear curve.
2, the engine intelligent variable valve timing system composition and working principle
2.1VVT-i system components
VVT-i system consists of the following four parts:
1) sensors, crankshaft position sensors, intake manifold air pressure sensors, throttle position sensors, water temperature sensors and camshaft position sensors are responsible for collecting engine load conditions and feedback information to the ECU.
2) The electronic control unit ECU and ECU store the best valve timing parameter value. The ECU collects the sensor information and compares it with the predetermined parameter value to calculate the correction parameter and issue the instruction to control the camshaft timing hydraulic control valve.
3) camshaft timing hydraulic control valve, according to the ECU command to control the position of the oil tank valve, that is, to change the hydraulic flow, the advance, lag, keep the same signal command to select the variable valve timing controller to the different oil On the road.
Out of the advantages of this system, the development trend.
4) variable valve timing controller, installed in the exhaust camshaft, known as the blade variable valve timing controller, installed in the intake camshaft, known as the spiral groove variable valve timing Controller. The two structures are somewhat different but have the same effect.