VVT-I. (Adjustable gas distribution phases) VVTL-I.(Adjustable gas and motion distribution phases) is designed to increase power and maintain an active state. VVT-I system Variable Valve Timing Intelligent - changing phases of gas distribution) allows you to smoothly change the phases of the gas distribution in accordance with the operating conditions of the engine. This is achieved by turning the camshaft inlet valves regarding the graft shaft in the range of 40-60? (at the corner of the corner of the crankshaft). As a result, the moment of starting opening of the intake valves and the amount of overlapping time (that is, the time when the exhaust valve is not yet closed, and the intake is already open).
Actuating mechanism VVT-I. It is placed in the camshaft pulley - the drive body is connected to an asterisk or gear pulley, a rotor - with a camshaft. The oil is supplied from one or another side of each of the rod petals, forcing it and the shaft itself is turned. If the engine is drunk? H, then the maximum delay angle is set (that is, an angle corresponding to the latest opening and closing of the inlet valves). To immediately after launch, when the pressure in the oil line is still not enough to effectively control VVT-I., there were no shocks in the mechanism, the rotor connects to the housing of the locking pin (then the pin is pressed by the oil pressure). Control VVT-I performed using the valve VVT-I. (OCV - Oil Control Valve). At the signal of the control unit, the electromagnet through the plunger moves the main spool, the airfold oil in one direction or another direction. When the engine is drunk? H, the spool moves the spring in such a way that the maximum delay angle is set. In the technology of the regulated system of the phase of gas distribution ( VVT-I.) A modern computer is used to change the operation of intake valves, depending on the motion conditions and engine load.
When closing the exhaust valve closure time and the opening time of the ink valves, the engine characteristics can be changed so that the desired engine torque is provided during its operation. This is yes? T is the best results in two areas: powerful acceleration and greater savings. In addition, more complete combustion of fuel at a higher temperature reduces environmental pollution.
Starting from the moment the Toyota was created VVT-I. The technology has opened the opportunity to consistently change the time, providing optimal engine operation under any conditions. That is why there is no need to set the time of operation of the valves, trying to prepare the engine in advance to the specified driving conditions. Or, in other words, your engine works equally smoothly in both the city and mountain alpine roads. Multiclapped technology Toyota VVT-I Used in many models of Toyota, including Toyota Corolla, Toyota Avensis, Toyota RAV4
VVT-I D4 Motor technology with direct injection, a new Singo-like Toyota nozzle increase combustion efficiency. Engine Toyota VVT-I (The adjustable gas distribution phase system) was enhanced with a small, but very effective idea. The fuel is now injected directly into each cylinder through a new slit nozzle. Work of a sliding nozzle Direct injection ? This is a small, but important improvement in your engine: increased fuel pulverization to achieve uniform combustion. The compression level is increased to 11.0 (compared with 9.8 in the engine VVT-I.). The fuel is no longer stopped on the nozzles with a cold engine, as a result of which the amount of carbon is reduced, and this means a cleaner and efficient engine. Engine VVT-I D4 8% more efficient than the winning awards and a very economical engine VVT-I.. VVTL-I. (Adjustable gas distribution phases and movement). Even? More power and ability to react with higher revolutions per minute. New Technology Toyota. VVTL-I. (Adjustable gas and motion distribution phases system) is based on the innovative and winning award valve management system VVT-I.. But what is different from not? VVTL-I.? Here is used? The cam mechanism, which not only changes the time, but also the magnitude of the inlet and exhaust valve. Electronic control device Toyota (ECU) It works on the principle - to increase the amount of air incoming and exiting at high engine speeds. It lifts four valves over the cylinder, so that it is increased by volume? M of the air falling into the combustion chamber, and the volume of exhaust products. An increased volume of air at high engine speeds (above 6000 rpm), means higher power, better combustion and reduction of environmental pollution. In engine VVTL-I.there are also many design innovations designed for life on the highway: the cylinder block is made of aluminum alloy, and the walls of the cylinders are made using technology MMC (METAL MATRIX COMPOSITE)to increase wear resistance. In addition, engineers Toyota. Created pistons with high performance, trying to extend the engine service time as well as improve the interaction between cylinders and pistons.
The efficiency of the internal combustion engine often depends on the gas exchange process, that is, filling the air-fuel mixture and removal of exhaust gases. As we already know with you, it is engaged in timing (gas distribution mechanism), if correctly and "finely" configure it under certain revs, you can achieve very bad results in the efficiency. Engineers have long been fighting over this problem, it is possible to solve it in various ways, for example, the impact on the valve themselves or the rotation of the camshafts ...
In order for the DVS valve, they always work correctly and were not susceptible to wear, first appeared simply "pushers", then, but it turned out to be little, so manufacturers began the introduction of so-called "phase students" on camshafts.
Why do you need phaserators?
To understand what phase studies and why they are needed, read the useful information to begin. The thing is that the engine is not the same in various revs. For idle and not high revolutions, the "narrow phases" will be ideal, and for high - "wide".
Narrow phases - If the crankshaft rotates "slowly" (idling), the volume and speed of removal of exhaust gases is also small. It is here that the "narrow" phases are perfectly used, as well as the minimum "overlap" (time of the simultaneous opening of intake and exhaust valves) - the new mixture is not pushed into the exhaust manifold, through the open exhaust valve, but also the exhaust gases (almost) do not pass in the intake . This is the perfect combination. If you make a "phasing" - wider, it is with low rotations of the crankshaft, then "testing" can be mixed with incoming new gases, thereby reducing its qualitative indicators, which will definitely reduce the power (the motor will not work unambiguously or even stalls).
Wide phases - When the turns grow, the volume and speed of pumped gases grow accordingly. It is already important here to quickly blow cylinders (from working out) and to drive the incoming mixture into them faster, the phases must be "wide".
Of course, the usual distributional shaft leads the discoveries, namely, his "cams" (peculiar eccentrics), he has two ends - one as if sharp, it stands out, the other is simply made by a semicircle. If the end is sharp - then the maximum opening occurs if the rounded (on the other side) is the maximum closure.
But the full-time distributional shafts - there is no phase adjustment, that is, they cannot expand them or do already, yet engineers set the averaged indicators - something mean between capacity and efficiency. If you fill the shafts into one of the parties, then efficiency, or the engine efficiency will fall. "Narrow" phases will not give the engine to develop maximum power, but "wide" - not work normally to work on small revs.
To regulate depending on the revolutions! This was invented - in fact, it is a phase regulatory system, a simple - phasemators.
Principle of operation
Now we will not climb deep, our task is to understand how they work. Actually, the usual camshaft at the end has a distribution gear, which in turn connects to.
Camshaft with a phase displayer at the end has a slightly different, modified design. Here are two "hydro" or electrofiled couplings, which, on the one hand, also engage in the GRM drive, and on the other hand with shafts. Under the influence of hydraulics or electronics (there are special mechanisms), shifts can occur inside this clutch, thus, it can rotate a little, thereby changing the opening or closing of the valves.
It should be noted that the phase inspector is not always installed on two camshafts immediately, it happens that one is in the inlet or on the graduation, and on the second is just an ordinary gear.
As usual, the process manages, which collects data from various, such as crankshaft positions, hall, engine speed, speed, etc.
Now I suggest you to consider the main designs, such mechanisms (I think you will become more clarified in my head more).
Vvt (VARIABLE VALVE TIMING), KIA-HYUNDAI (CVVT), Toyota (VVT-I), Honda (VTC)
Some of the first were offered to turn the crankshaft (relative to the initial position), Volkswagen, with his VVT system (based on its systems a lot of other manufacturers built its systems)
That it includes:
Phase pazers (hydraulic) are installed on inlet and graft shaft. They are connected to the motor lubrication system (actually it is oil and pumps them into them).
If you disassemble the coupling, then inside there is a special asterisk of an outdoor case, which is still connected to the rotor shaft. The housing and the rotor when pumping oil can be shifted relative to each other.
The mechanism is fixed in the block head, it has channels for lining oil to both couplings, the streams are controlled by two electro-hydraulic distributors. By the way, they are also fixed on the body of the block head.
In addition to these distributors in the system, there are many sensors - the frequency of the crankshaft, the load on the engine, the temperature of the coolant, the position of the distribution and knees of the shafts. When you need to rotate correct the phases (for example, high or low speed), the computer reading data gives orders to feed oils into the coupling, they open and oil pressure begins to pump the phase beams (thus they turn to the desired direction).
Idling - Turning occurs in such a way that the "intake" camshaft provided a later discovery and later closing of the valves, and the "graduation" unfolds so that the valve closes much earlier before the piston approach in the upper dead point.
It turns out that the amount of exhaust mixture decreases almost to a minimum, and it practically does not interfere with the intake tact, it favorably affects the operation of the motor at idle, its stability and uniformity.
Middle and high speed - Here is the task to give maximum power, therefore "turning" occurs in such a way as to delay the opening of the exhaust valves. Thus, it remains the pressure of the gases on the workstop tact. Ink, in turn, open after reaching the piston of the upper dead point (NTC), and closes after NMT. Thus, we, as it were, we obtain the dynamic effect of "recovery" of the engine cylinders, which carries an increase in power.
Maximum torque - How it becomes clear, we need to fill cylinders as much as possible. To do this, it is necessary to open much earlier and, accordingly, much later to close the inlet valves, save the mixture inside and prevent it from the output back to the intake manifold. "Graduation", in turn, closes with some advance to VTC to leave a small pressure in the cylinder. I think it is understandable.
Thus, there are now many similar systems, of which are the most common Renault (VCP), BMW (Vanos / Double Vanos), KIA-HYUNDAI (CVVT), Toyota (VVT-I), Honda (VTC).
But these are not perfect, they can only shift the phases in one or the other side, but cannot really "narrow" or "expand" them. Therefore, more advanced systems are beginning to appear.
Honda (VTEC), Toyota (VVTL-i), Mitsubishi (Mivec), Kia (CVVL)
To additionally adjust the lift of the valve, there were even more advanced systems, but the company was Honda, with its motor Vtec.(VARIABLE VALVE TIMING AND LIFT ELECTRONIC CONTROL). The essence is that in addition to changing the phases, this system can more lift the valve, thereby improving the filling of cylinders or removal of exhaust gases. Honda now has a third generation of such engines that absorbed both VTC systems (phase studies) and VTEC (valve raising) immediately, and now it is called - Dohc. i- Vtec. .
The system is even more complicated, it has advanced camshafts in which there are combined cams. Two ordinary on the edges, which are pressed on the rocker in the usual mode and the average more advanced cam (high-profile), which turns on and presses the valve to say after 5,500 revolutions. This design is available on each pair of valves and rocker.
How does it work Vtec? Approximately 5500 rpm The motor operates in normal mode, using only the VTC system (that is, the phase beams). The medium cam is not closed with two others around the edges, it simply rotates empty. And when achieving high revolutions, the ECU gives an orders to turn on the VTEC system, it starts to pump the oil and the special pin is pushed forward, it allows you to close all three "cam" immediately, the highest profile starts working - now it is he who gives a couple of valves that are designed Group. Thus, the valve is lowered much more, which makes it possible to additionally fill the cylinders with a new working mixture and take the larger amount of "testing".
It is worth noting that VTEC stands on intake and graduation shalads, this gives a real advantage and increase in power at high revs. The increase in approximately 5 - 7% is a very good indicator.
It is worth noting, although Honda was first, now similar systems are used on many cars, such as Toyota (VVTL-i), Mitsubishi (Mivec), Kia (CVVL). Sometimes, for example, in KIA G4NA engines, the valve elevator is used only on one camshaft (here only in the inlet).
But this design has its drawbacks, and the most important thing is a stepped inclusion in the work, that is, eat up to 5000 - 5500 and then you feel (fifth point) inclusion, sometimes like push, that is, there is no smoothness, but I would like it!
Smooth inclusion or Fiat (Multiair), BMW (Valvetronic), Nissan (VVEL), Toyota (Valvematic)
You want smoothness please, and here the first in the development was the company (drum fraction) - Fiat. Who would have thought, they first created the Multiair system, it is even more complicated, but more accurate.
"Smooth work" here is applied here on intake valves, and there is no camshaft here at all. It was preserved only at the prom, but it has an impact on the inlet (probably launched, but I will try to explain).
Principle of operation. As I said, there is one shaft here, and it leads both intake and exhaust valves. However, if it is mechanically exposed to "graduation" (that is, it is trite through the cams), then it is transmitted to inlet exposure through a special electro-hydraulic system. On the shaft (for intake) there is something like "cams", which are pressed not on the valve themselves, but on the pistons, but they transmit orders through the electromagnetic valve on working hydraulic cylinders to open or close. Thus, it is possible to achieve the desired opening at a certain period of time and revolutions. With small circulation, narrow phases, with high - wide, and the valve is extended to the desired height, because everything is controlled by hydraulics or electrical signals.
This allows you to make smooth inclusion depending on the engine speed. Now there are also many manufacturers such as many manufacturers, such as - BMW (Valvetronic), Nissan (VVEL), Toyota (Valvematic). But these systems are not perfect until the end, what is wrong again? Actually, there is again the drive of the timing (which takes about 5% of the power), there is a camshaft and throttle, it takes a lot of energy again, respectively steals the efficiency, I would refuse them.
Vvti Toyota What is it and how is it arranged? VVT-I - the constructors of the Toyota autoota control system of gas distribution phases, which have come up with their system of increasing the efficiency of internal combustion engines.
This does not mean that such mechanisms are only at Toyota, but consider this principle on its example.
Let's start with the decryption.
The Abbreviation VVT-I sounds in the original language as Variable Valve Timing Intelligent, which is translated as an intelligent change in the phases of gas distribution.For the first time on the market, this technology is represented by Toyota Ten years ago, in 1996. There are similar systems in all autocontracens and brands, which speaks of their benefits. They are called, however, everything is different, in full swing of ordinary motorists.
What brought VVT-I to the Motor Building? First of all, the increase in power is uniform in the entire range of revolutions. Motors have become more economical, and therefore more efficiently.
The gas distribution phase control or the moment of raising and lowering the valves occurs by turning to the desired angle.
How it is implemented technically, consider further.
Vvti Toyota What is this or how does the VVT-I gas distribution work?
The VVT-I Toyota system is what it is for what, we understood. Time to deepen in its inside.
The main elements of this engineering masterpiece:
- coupling VVT-I;
- solenoid valve (OCV - OIL CONTROL VALVE);
- control block.
The algorithm of all this design is simple. The coupling, which is a pulley with cavities inside and the rotor, fixed on the camshaft, is filled with oil under pressure.
The cavities are somewhat, and for this filling answers the VVT-I valve (OCV) acting by commands of the control unit.
Under the pressure of oil, the rotor together with the shaft can be rotated at a certain angle, and the shaft is already, in turn, determines when climbing and dropping valves.
In the start position, the position of the camshaft of the intake valves provides maximum cravings on low motor revolutions.
With an increase in the speed of rotation, the system turns the camshaft in such a way that the valves open earlier and closed later - it helps to increase the return on high revs.
As we see, the technology of VVT-I, the principle of which considered, is quite simple, but, nevertheless, effective.
Development of VVT-I technology: What else did the Japanese come up with?
There are other varieties of this technology. So, for example, Dual VVT-I manages work not only camshaft inlet valves, but also graduation.
This made it possible to achieve even higher engine parameters. Further development of the idea was called VVT-IE.
Here, the Toyota engineers have completely abandoned the hydraulic method of controlling the camshaft position, which had a number of disadvantages, because for turning the shaft it was necessary that the oil pressure rose to a certain level.
To eliminate this lack, it was possible to eliminate the electric motors - now they turn shafts. That's how.
Thank you for your attention, now you yourself can answer anyone to the question "VVT-I Toyota what it is and how it works."
Do not forget to subscribe to our blog and to new meetings!
· 08/20/2013
This system provides an optimal intake moment in each cylinder for the data of the specific operating conditions of the engine. VVT-I almost eliminates the traditional compromise between the large torque on low revs and high high power. Also, VVT-I provides greater fuel economy and so effectively reduces emissions of harmful combustion products, which disappears the need for exhaust recycling system.
VVT-I engines are installed on all modern Toyota cars. Similar systems are developed and applied by a number of other manufacturers (for example, the VTEC system from Honda Motors). The Toyota VVT-I system replaces the previous VVT system (2-speed hydraulic drive control system) used since 1991 on 20-valve 4A-GE engines. VVT-I has been used since 1996 and manages the moment of opening and closing the inlet valves by changing the transmission between the camshaft drive (belt, gear or chain) and actually camshaft. A hydraulic drive is used to control the position of the camshaft (motion oil under pressure).
In 1998, Dual ("Dual") VVT-I, controlling and intake, and exhaust valves appeared (first installed on the 3S-GE engine on the RS200 Altezza). Also, double VVT-I is used on new V-shaped Toyota engines, for example, on a 3.5-liter V6 2GR-FE. Such an engine is installed on Avalon, RAV4 and Camry in Europe and America, on Aurion in Australia and on various models in Japan, including Estima. Double VVT-I will be used in future Toyota engines, including a new 4-cylinder engine for a new generation Corolla. In addition, dual VVT-I is used in the D-4S 2GR-FSE engine on Lexus GS450H.
Due to the change in the opening of the launch valves and the engine stop, the compression is minimal, and the catalyst is very quickly heated to the operating temperature, which dramatically reduces harmful emissions into the atmosphere. VVTL-I (decoded as Variable Valve Timing and Lift with Intelligence) Based on VVT-I, the VVTL-I system uses camshaft, which also controls the value of the opening of each valve when the engine is operating at high revs. This makes it possible to ensure not only higher revisions and greater engine power, but also the optimal opening of each valve, which leads to fuel economy.
The system is developed in collaboration with Yamaha. VVTL-I engines are installed on modern Toyota sports cars, such as Celica 190 (GTS). In 1998, Toyota began to offer a new VVTL-I technology for a two-string 16-valve engine 2zz-GE (one camshaft controls intake, and the other outlet valves). On each camshaft there are two cams per cylinder: one for low revolutions, and the other for high (with a great opening). On each cylinder - two intake and two exhaust valves, and each pair of valves is driven by one swing lever, which is affected by the camshaft cam. On each lever there is a spring-loaded sliding pusher (the spring allows the pusher to slide freely on a "high-shortest" cam, without affecting the valves). When the engine shaft rotation speed is below 6000 v / m, the "low-speed cam" is affected by the swing lever through a normal roller pusher (see Fig.). When the frequency exceeds 6000 rpm / m, the engine control computer opens the valve, and the oil pressure shifts the heel under each sliding pusher. The stud pushing the sliding pusher, as a result of which it is no longer moving freely on its spring, but begins to transmit a swing lever from the "high-turn" cam, and the valves open more and for more.
Toyota 1ZR-Fe / FAE 1.6 l engine.
Engine Characteristics Toyota 1ZR
| Production | Toyota Motor Manufacturing West Virginia Shimoyama Plant. |
| Engine brand | Toyota 1Zr. |
| Years of release | 2007 |
| Cylinder block material | aluminum |
| Supply system | injector |
| A type | in line |
| Number of cylinders | 4 |
| Valves on cylinder | 4 |
| Piston stroke, mm | 78.5 |
| Cylinder diameter, mm | 80.5 |
| Compression ratio | 10.2 10.7 |
| Engine volume, ccmm | 1598 |
| Engine Power, L.S. / Ob. Min | 126/6000
134/6400 |
| Torque, Nm / Ob.min | 157/5200
160/4400 |
| Fuel | 95 |
| Environmental norms | Euro 5. |
| Engine weight, kg | - |
| Fuel consumption, l / 100 km (for Corolla E140) - city - Rouss - Mixed. |
8.9 5.8 6.9 |
| Oil consumption, gr. / 1000 km | up to 1000. |
| Engine oil | 0W-20 5W-20 5W-30 10W-30. |
| How much engine oil | 4.7 |
| Replacing the oil is carried out, km | 10000
(better than 5000) |
| Engine operating temperature, hail. | - |
| Engine resource, thousand km - According to the plant - on practice |
N.D. 250-300 |
| Tuning - Potential - without loss of resource |
200+ n.D. |
| The engine was installed | Toyota Auris. Toyota Verso. Lotus Elise. |
Motor malfunction and repair 1ZR-FE / FAE
These motors were represented by the public in 2007 and were considered as the successor of the unsuccessful ZZ series. The family consisted of 1.6 liter 1Zr, 1.8 liters. , 2.0 l. , as well as the Chinese 4ZR, a working volume of 1.6 liters. and 5zr 1.8 l. Consider the youngest representative of the main model range - 1ZR, this engine was called upon to replace the motor. In the new 1zr, to reduce loads on the sleeve, the axis of cylinders does not intersect with the crankshaft axis, DUAL VVT-I began to be applied, simply speaking, the system of changing the phases of gas distribution on intake and graduation rates, at the same time appeared the Valvematic system that changes the valve lifting (range 0.9 - 10.9 mm), hydrocomathers appeared and now the adjustment of the valves for 1ZR does not threaten you. According to the new tradition of Toyota, the ZR engine is disposable, in an aluminum unit, without repair sizes, with all the resulting.
Motor modifications Toyota 1ZR
1. 1ZR-FE - the main engine, equipped with a double VVTI, compression ratio 10.2, power 124 hp This engine was combined toyota Corolla and Toyota Auris.
2. 1ZR-FAE - analogue 1ZR-FE, but with Dual-VVTI, Valvematic is used, the compression ratio is increased to 10.7, engine power 132 hp
Malfunctions, problems 1zr and their causes
1. High oil consumption. The problem is characteristic of the first models of Zr, solved by the fill with the viscosity of the W30, instead of 0W-20, 5W-20. If the mileage is serious, then measure the compression.
2. 1Zr engine knock. Noise on medium revolutions? Change the timing chain tensioner. In addition, the drive belt of the generator can also make noise (whistle).
3. Problems with idle. Swimming and other troubles are provoked by the sensor of the throttle position and the dirty throttle valve.
In addition, the pump on 1ZR likes to leak, make noise and ask for a landfill after 50-70 thousand km, often dies the thermostat and the engine refuses to warm up to the operating temperature, can jarny VVTI valve with subsequent car stupidity and power loss. Nevertheless, these problems are not solid and nearby, the 1ZR engine turned out to be not bad, with a normal resource (+ \\ - 250 thousand km) and during stable maintenance, the owner does not deliver problems.
Toyota 1ZR-FE / FAE engine tuning
Turbine per 1zr.
The turbine of the engine Zr is described, on the example of 2ZR and successfully repeats on 1Zr / engine.
