What does VTDEO mean, what does vvt mean

VVT stands for Variable Valve Timing System.

VVT is an abbreviation for Variable Valve Timing, also known as the Variable Valve Timing System. Variable Valve Timing (VVT) is a modern automotive engine control technology. The VVT system is mainly composed of electronic control unit (ECU), camshaft, valve, hydraulic controller and oil pump.

In the VVT system, the ECU uses sensors to sense information such as vehicle speed, accelerator pedal position, engine load and temperature to control the engine's intake and exhaust systems and dynamically adjust valve timing and duration. The VVT system can be controlled in different ways, including hydraulic and electronically controlled.

The hydraulic control mode is to control the oil pressure through the hydraulic controller, adjust the phase of the camshaft and the timing of the valve, so as to realize the dynamic adjustment of the valve. The electronic control mode controls the oil circuit through the electric control valve to realize the dynamic adjustment of the valve timing.

The key to the VVT system is the design of the camshaft. The shape and structure of the camshaft affects the opening time and duration of the valve. Depending on the driving situation and road conditions, the VVT system optimizes the timing and duration of the valves by controlling the phase and angle of the camshaft.

Advantages of VVT:

1. Improve fuel economy: VVT technology can dynamically adjust the valve timing and duration according to different driving conditions, so that the combustion efficiency of the engine is higher, thereby reducing fuel consumption and emissions.

2. Improve power output: VVT technology can maximize the combustion efficiency and power output of the engine under different loads, thereby improving the acceleration ability and driving performance of the vehicle.

3. Emission reduction: By dynamically adjusting the valve timing and duration, the VVT technology can optimize the combustion process, reduce exhaust emissions, and reduce environmental pollution.

4. Improve driving comfort: VVT technology can make the engine work more smoothly under different loads, reduce noise and vibration, and improve driving comfort.

5. Increase engine life: Because VVT technology can optimize the combustion process and reduce the load and wear of the engine, it can extend the service life of the engine.

6. Improve the intelligent level of the engine: VVT technology can dynamically adjust the valve timing and duration through the electronic control unit (ECU), realize the intelligent control of the engine, and improve the performance and reliability of the engine.

vt, in English, is the identification of transitive verbs, an abbreviation for transitive verb.

vt.Refers to a transitive verb that can be followed directly by an object.

vi.It refers to an intransitive verb that cannot be followed by an object.

n.Nouns.

adj.refers to an adjective.

adv.Refers to an adverb. Noun noun (abbreviated as n.)

Adjective (abbreviated as adj.)）；The verb verb (abbreviated as v.)）；The preposition proposition (abbreviated as prep.)

Adverb (abbreviated as adv.)）；The conjunction conjunction, abbreviated as conj)。

vt.The meaning of the transitive verb, vtIt is an abbreviated form of transitiveverb in English.

Corresponding to this are:

vi., which means an intransitive verb and is an abbreviated form of intransitiveverb;

v., which means verb and is an abbreviated form of verb.

Extended information: In English, whether it is possible to directly follow the object after pressing a verb can divide verbs into two types: transitive verbs and intransitive verbs.

Words in the dictionary are marked with vtis a transitive verb with viis an intransitive verb.

Transitive verbs refer to verbs that can be objected to nouns, pronouns, and gerunds.

Transitive verbs can be directly followed by objects. Intransitive verbs cannot be followed directly by the object with action (i.e., the object), and if you want to follow the object, you must first add a preposition after it, such as to, of, at, etc., before you can follow the object.

The so-called "transitive", "and" have the meaning of "following, reaching, and relating from the back", and "transitive" means that it needs to take "thing" to complete an action, and this action has an object, and this object is the object to be added after it, that is, the predicate in the usual sense, and the verb that can be directly added to the object after it generally has a passive form; The intransitive verb has no passive form, its action has no object, but only indicates a certain state, and it cannot be directly added as an object, but a preposition needs to be added.

In fact, many verbs are both transitive and intransitive.

For example: begin

shallibegin

atonce?Can I get started right away? (begin as an intransitive verb) shebegan

workingasa

librarian

aftersheleft

school.She became a librarian after graduating. (began).

Variable Valve Timing (VVT) is a technology used in automotive piston engines. VVT technology adjusts the overlap time and timing (some or all of it) in the engine's intake and exhaust systems, reducing fuel consumption and increasing efficiency.

In 1991, the University of Clemson in the United States invented a more advanced intake and exhaust valve continuously variable valve timing and obtained a patent.

American Society of Mechanical Engineers, Clemson Camshaft Boosts Auto Fuel Economy, Mechanical Engineering-CIME (1991-12-01)), after which BMW Automotive became a close partner with the university's Department of Mechanical Engineering. In 1995, Honda Motors, a leading partner of the British Rover Automobile Group, invented another continuously variable valve timing technology, VVC.

Extended information: Toyota's VVT-i system continuously adjusts valve timing, but not valve lift. Its working principle is: when the engine is converted from low speed to high speed, the electronic computer automatically presses the oil to the small turbine in the intake camshaft to drive the gear, so that under the action of pressure, the small turbine rotates at a certain angle relative to the gear housing, so that the camshaft rotates forward or backward within the range of 60 degrees, so as to change the moment of opening the intake valve, and achieve the purpose of continuously adjusting the valve timing.

VVT (Variable Valve Timing) is a variable valve timing system. The system adjusts the phase of the engine cam through the control and actuation system, so that the opening and closing time of the valve changes with the change of engine speed, so as to improve the charging efficiency and increase the engine power.

How it works. The principle of variable valve timing technology (VVT) is to adjust the intake (exhaust) volume, valve opening and closing time and angle according to the operation of the engine, so that the amount of air entering reaches the best value and improves the combustion efficiency. The advantages are fuel saving and large power-to-lift ratio; The disadvantage is that the torque in the middle section is insufficient.

The crankshaft is driven to rotate by the toothed gearing, so that the valve will form a certain correspondence with the rotation angle of the crankshaft when opening and closing. The flow of gas will change with the speed of the engine, how to make the cylinder at different speeds can get good air intake efficiency? To do this, it is necessary to change the opening and closing times of the valves.

The hydraulic device mounted at the front end of the camshaft allows the camshaft to rotate at a small angle to allow the intake valve to open earlier when the speed increases.

The use of variable valve timing mechanism can improve the performance of the engine. Different engine speeds require different gas distribution timings. This is because:

When the engine speed changes, the effect of using airflow inertia to increase intake and promote exhaust during late valve closure will be different because the intake flow rate and the exhaust gas velocity during the forced exhaust period also change.

For example, when the automobile engine is running at low speed, the inertia of the air flow is small, and if the gas distribution timing remains unchanged at this time, part of the intake air will be pushed out of the cylinder by the piston, so that the air intake volume will be reduced, and the residual exhaust gas in the cylinder will increase. When the engine is running at high speed, the inertia of the airflow is large, if the intake delay angle and valve overlap angle are increased at this time, the air intake volume will be increased and the residual exhaust gas volume will be reduced, so that the engine ventilation process will be perfected.

In short, the valve timing of a four-stroke engine should be that the intake delay angle and valve overlap angle increase with the increase of engine speed.

If the valve lift can also increase with the increase of engine speed, it will be more conducive to obtaining good engine high-speed performance.

Related systems. Variable Valve Timing (OCV VCT).

The OCV VCT consists of a solenoid valve (OCV) and a variable camshaft phase regulator (VCT), which adjusts the engine cam phase so that the air intake can change with the change of engine speed, so as to achieve the best combustion efficiency and provide fuel economy.

VVT is the engine variable valve timing technology (VVT, variable valve timing) principle is to adjust the amount of intake (exhaust), valve opening and closing time, and angle according to the operation of the engine. The amount of incoming air is optimal, and the combustion efficiency is improved. The advantages are fuel saving and large power-to-lift ratio; The downside is that the mid-range rpm torque is insufficient.

VVT-i is an abbreviation for Variable Valve Timing-Intelligent, which means that the intake valve opens and closes to increase the amount of inflation.

According to the instructions of the engine ECU, when the camshaft timing control valve is located in Figure (A), the oil pressure is applied to the left side of the piston, causing the piston to move to the right. Due to the action of the rotating spline on the piston, the intake camshaft is positioned at an angle in relation to the camshaft timing pulley. When the camshaft timing control valve is in the position of Figure (b), the piston moves to the left and rotates in the direction of delay.

In addition, the camshaft timing control valve hand width closes the oil passage and maintains the pressure balance on both sides of the piston, thereby maintaining the valve phase and thus obtaining the ideal valve timing. Improving the charging efficiency is an important measure to improve the power performance of the engine. In addition to supercharging, it is an important way to improve the charging efficiency by reasonably selecting the gas distribution phase that can change with the different engine speeds, and using the inertia and resonance effects of the intake air with the core.

The intake inertia and resonance effects vary with the engine speed, the length of the intake pipe and the size of the pipe diameter. At different speeds, the length of the intake pipe should be different to obtain a good intake inertia effect. Moreover, only by adopting variable valve phase, the variable air intake system can adapt to the requirements of Bi Xingliang at different engine speeds, and can improve the engine performance more comprehensively.