Automatic torque converter: photo, principle of operation, malfunctions, automatic transmission torque converter replacement

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:41

Recently, cars with automatic transmissions have begun to be in great demand. And no matter how much motorists say that automatic transmission is an unreliable mechanism that is expensive to maintain, statistics say the opposite. Every year there are fewer cars with manual transmission. The convenience of the "machine" was appreciated by many drivers. As for expensive maintenance, the most important part in this box is the automatic transmission torque converter. A photo of the mechanism and its device are further in our article.

Characteristic

In addition to this element, the design of an automatic transmission includes many other systems and mechanisms. But the main function (this is the transmission of torque) is performed by the automatic transmission torque converter. In common parlance, it is called a "donut" due to the characteristic shape of the structure.

It is worth notingthat on automatic transmissions for front-wheel drive cars, the automatic transmission torque converter includes a differential and final drive. In addition to the function of transmitting torque, the donut absorbs all vibrations and shocks from the engine flywheel, thereby smoothing them to a minimum.

Design

Let's look at how the automatic transmission torque converter works. This element consists of several nodes:

• Turbine wheel.
• Lockup clutch.
• Pump.
• Reactor wheel.
• Freewheels.

All these mechanisms are placed in a single case. The pump is directly connected to the engine crankshaft. The turbine mates with the gears of the gearbox. The reactor wheel is placed between the pump and the turbine. Also in the design of the “donut” wheel there are blades of a special shape. The operation of an automatic transmission torque converter is based on the movement of a special fluid inside (transmission oil). Therefore, the automatic transmission also includes oil channels. In addition, it has its own radiator. What it is for, we will consider a little later.

As for the clutches, the blocking clutch is designed to fix the position of the torque converter in a certain mode (for example, "parking"). The freewheel is used to rotate the reactor wheel in the opposite direction.

The principle of operation of the automatic transmission torque converter

How does this element work in the box? All actions of the "donut" are carried out in a closed cycle. So, the main working fluid here is the “transmission”. It is worth noting that it differs in viscosity and composition from those used in mechanical boxes. During the operation of the torque converter, lubricant flows from the pump to the turbine wheel, and then to the reactor wheel.

Thanks to the blades, the liquid begins to rotate faster inside the donut, thereby increasing the torque. When the crankshaft speed increases, the angular velocity of the turbine and impeller equalize. The fluid flow changes its direction. When the car has already gained sufficient speed, the "donut" will only work in fluid coupling mode, that is, it will only transmit torque. When the speed of movement increases, the GTF is blocked. In this case, the clutch is closed, and the transmission of torque from the flywheel to the box is carried out directly, with the same frequency. The element disengages again when shifting to the next gear. This is how the smoothing of the angular velocities occurs again until the moment when the speed of rotation of the turbines is not equal.

Radiator

Now about the radiator. Why is it separately displayed in automatic transmissions, because such a system is not used on the “mechanics”? Everything is very simple. On a mechanical gearbox, the oil only performs a lubricating function.

At the same time, it is only half filled. The fluid is contained in the transmission pan and the gears are wetted in it. In an automatic transmission, the oil performs the function of transmitting torque (hence the name "wet clutch"). There are no friction discs here - allenergy goes through turbines and oil. The latter is constantly moving in channels under high pressure. Accordingly, the oil needs to be cooled. For this, such a transmission is provided with its own heat exchanger.

Faults

The following transmission failures are distinguished:

• GTP malfunction.
• Brake band and friction clutch failure.
• Faulty oil pump and control sensors.

How to identify a breakdown?

It is quite difficult to find out which element is out of order without dismantling the box and disassembling it. However, it is possible to predict a serious repair by several signs. So, if there are malfunctions of the automatic transmission torque converter or brake band, the box will “kick” when switching modes. The car starts to twitch if you put the handle from one mode to another (and when the foot is on the brake pedal). Also, the box itself enters emergency mode. The car only moves in three gears. This suggests that the box needs serious diagnostics.

As for the replacement of the torque converter, it is carried out with the complete dismantling of the box (the drive shafts, the "bell" and other parts are disconnected). This element is the most expensive component of any automatic transmission. The price of a new gas turbine engine starts at $ 600 for budget car models. Therefore, it is important to know how to properly use the box in order to delay repairs as much as possible.

How to save PPC?

It is believed that the resource of this transmission is an order of magnitudelower than mechanics. However, experts note that with proper maintenance of the unit, you will not need to repair or replace the automatic transmission torque converter. So, the first recommendation is a timely oil change. The regulation is 60 thousand kilometers. And if at the manual transmission the oil is filled for the entire period of operation, then in the “machine” it is the working fluid. If the grease is black or has a burning smell, it needs to be replaced immediately.

The second recommendation concerns compliance with temperature regimes. Do not start driving too early - the temperature of the box oil should be at least 40 degrees. To do this, move the lever through all modes with a delay of 5-10 seconds. So you warm up the box and prepare it for operation. It is undesirable to drive in cold oil, as well as in very hot. In the latter case, the liquid will literally burn (when replacing, you will hear the smell of burning). The automatic transmission is not suitable for drifting and hard use. Also, do not turn on the neutral gear on the go, and then turn on the “drive” again. This will break the brake band and a number of other important elements in the box.

Conclusion

So, we found out what an automatic transmission torque converter is. As you can see, this is a very important node in the box. It is through it that torque is transmitted to the box, and then to the wheels. And since the oil here is the working fluid, it is necessary to follow the regulations for its replacement. So the box will delight you with a long resource and smooth switching.