如果气门关闭不严，发动机就不能发挥出全部的功率。
If the valves do not close fully the engine will not develop full power.
气门关闭，活塞在气缸内上移，压缩空气燃烧混合物。
The intake valve closes and the piston moves up in the cylinder, compressing the fuel mixture.
怠速转速控制逻辑是用于控制节气门关闭后的发动机转速。
The purpose of the idle speed control logic is to control engine speed at closed throttle.
由于进气门关闭、排气门也已关闭，现在活塞上部的空间被密封了。
The space above the piston is now sealed due to the inlet valve closing and the exhaust valve having already closed.
在压缩行程，活塞向上运动，进气门和排气门关闭，活塞压缩混合气。
On the compression stroke, the piston moves up. The intake valve and exhaust valve close. The piston compresses the air-fuel mixture.
在作功行程，进气门和排气门关闭，火花塞点燃混合气，活塞向下移动。
On the power stroke, the intake valve and exhaust valve close. The spark plug ignites the air-fuel mixture, the piston moves down.
当活塞到达进气行程的下止点时，随着空气燃油的混合气进入气缸，进气门关闭。
When the piston reaches the bottom of the intake stroke, the intake valve closes, trapping the air-fuel mixture in the cylinder.
本文介绍了一种基于可变位置液压张紧器机构实现控制进气门关闭相位角的电控可变配气相位系统。
A new developed electrical control VVT system is presented which USES a tensioner with variable working position to change the intake valve-closing Angle.
气门不过是装在阀杆上加工精细的金属塞而已。当气门就位时（向上移动阀口）时，即可将气门关闭。
The valves are nothing more than accurately machined metal plugs (on long stems) that close the openings when they are seated (have moved up into the openings).
进气冲程在活塞位与气缸顶部（进气门开启，排气门关闭）时开始，在活塞到达其行程的底部时结束。
The intake stroke starts with the pistonat the top of the cylinder (intake valve open and exhaust valve closed) and stops with the pistonat the bottom of its travel.
详细阐述了液压张紧器式可变配气相位机构的设计，并通过试验获得了最佳气门关闭角的提前与滞后角度。
This paper presents a new design of hydro extender VVT mechanism. The best matching inlet valve closing timing for advancement and retarding is achieved by the experiments.
推荐可变压缩比（VCR）方案、可变废气再循环率（EGR）方案、可变排气门关闭时刻方案，以及废气再循环滚流分层充气方案等。
Schemes of variable compression ratio (VCR), variable exhaust gas recirculation (EGR), variable exhaust valve timing, and EGR with stratification by tumble charge flow are recommended.
结果表明，通过调节排气门关闭正时，适当增大缸内残余废气量，可显著改善起动过程初始着火循环的着火燃烧性能和提高起动过程缸内燃烧的稳定性。
The results show that a proper increase of residual gas fraction could promote ignition and combustion stability of first firing cycle significantly during cold start.
这意味着操作机构必须离阀门足够远以允许阀门通过气门弹簧使其完全关闭。
This means that the operating mechanism must be able to move sufficiently far enough away from the valve to allow the valves to be fully closed against its seat by the valve spring.
然而气门达到全开位置需要一定时间，完全关闭也需要一定时间。
However, it takes some time for the valve to open to its full position. It also takes time for it to close tightly.
在上止点前打开进气门并在下止点增大气缸内的油气混合物之后关闭。
Opening the intake valve before TDC and closing it after BDC increase the fill of air-fuel mixture in the cylinder.
弹簧处于“压缩”状态时，意味着弹簧试图伸展，气门受弹簧作用而处于关闭状况。
The spring is under compression, which means that it tries to expand and therefore spring-loads the valve in the closed position.
在发动机中，凸轮轴上的凸轮控制进气门和排气门的开启和关闭。
In the engine, cams on the CAM shaft cause the intake and exhaust valves to open.
计算分析了进排气门实际关闭相位，并根据低压示功图中气门落座冲击引起的干扰信号间接确定发动机运转时的实际关闭相位。
The actual valve closing phases have been calculated, analyzed and determined in accordance with the interference signals caused by valve seating impulse in the low pressure indicator diagram.
气门杆上的弹簧使气门保持在气门座上(关闭状态)。弹簧的下端抵在气缸盖上。
A spring on the valve stem tends to hold the valve on its seat (closed). The lower end of the spring rests against the cylinder head.
所以阀门能完全关闭，气门间隙在操作机构内是必须的。
So that the valves can close fully some clearance is needed in the operating mechanism.
当这发生时，气门弹簧紧紧地关闭气门口，叫做气门座。
As this occurs, valve springs pull the valve tightly closed against its opening, called the valve seat.
但是像进气门一样，排气门需要时间到达充分打开和关闭的位置。
But like the inlet valve, the exhaust valve needs time to reach the full-open position, it also needs time to reach the full-closed position.
气门杆上的弹簧使气门保持在气门座上(关闭状态)。
A spring on the valve stem tends to hold the valve on its seat (closed).
通过对模糊控制器的设计，计算出EQ6 10 0汽油机在不同工况下的排气门提前开启角和进气门滞后关闭角的模糊控制值。
The fuzzy control values of the optimized exhaust lag angle and intake advance angle of the EQ6100 engine are calculated by designing the fuzzy controller.
通过对模糊控制器的设计，计算出EQ6 10 0汽油机在不同工况下的排气门提前开启角和进气门滞后关闭角的模糊控制值。
The fuzzy control values of the optimized exhaust lag angle and intake advance angle of the EQ6100 engine are calculated by designing the fuzzy controller.
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