Despite the growing popularity of cars withautomatic gearbox, the classic mechanics are still in high esteem among many drivers. It is more reliable than automatic transmission. But during operation the driver is constantly forced to work with the clutch pedal. This gives some inconvenience, especially in traffic. So there was a hydromechanical transmission. The principle of its work and the device will be considered in our today's article.
Those drivers who do not want to work withclutch, give preference to this particular transmission. Hydromechanical gearbox performs several functions at once. It combines the clutch and the classic box.
Hydromechanical gearbox assemblypresupposes the presence of a hydraulic transformer. This element, depending on the design features, can be two-, three- and multi-shaft. Now manufacturers use a planetary automatic hydromechanical gearbox.
How does the CVT work?
On trucks and large buses more oftena multi-shaft transmission is used. To switch gears, multi-plate clutches are used here. For their work, lubrication is necessary. The oil of a hydromechanical gearbox differs significantly in consistence from "mechanics". In the latter case, it is more dense. In order to include the first and the back speed on hydromechanics, gear couplings are used. This design allows you to smoothly transfer torque from the flywheel to the wheels.
Now this is more common hydromechanical gearbox.
How the Planetary Transmission Works
Its algorithm of work is extremely simple.The gears are switched on the planetary hydromechanical transmission using friction clutches. Also, to smooth the blows when switching to a lower one, a special brake band is used. It is during the operation of the "brake" that the torque transmission force is reduced. But at the same time the switching speeds are smoother than the analogue ones.
At the heart of the planetary transmission is a hydraulic transformer. This element is located between the engine and the gearbox. GDF consists of several components:
- The gear wheel.
In the people this element is called a "bagel" because of its characteristic shape.
Features of the design of the planetary gearbox
Planetary hydromechanical gearboxconsists of the drive shaft on which the articulated gear is located. Also, there are satellites rotating on separate axes. These elements are meshed with the inner teeth of the box and the ring gear. Transmission of torque is due to the action of the brake band. She brakes the ring gear. As the car accelerates, their speed increases. The driven shaft, which perceives the transmission of the torque from the master, is engaged.
As for the coefficient of efficiency, it is an order of magnitude lower than in the global PPC.
Maintenance and repair of hydromechanical gearbox
When using this transmission, it is necessaryfollow the oil level. This fluid here is working. It is the oil that uses the turbines to transfer the torque. On mechanical boxes, it simply lubricates rubbing gears. Manufacturers recommend replacing the oil on hydromechanical boxes every 60 thousand kilometers. It is worth noting that in the design of such a checkpoint has its own filter. It also changes when this time is reached. Operation at a low level of oil threatens to stall and overheat the transmission.
How to extend the resource
To extend the service lifehydromechanical box, it is necessary to monitor the oil level. If it is insufficient, the box overheats. The operating temperature should not exceed 90 degrees. Modern cars are equipped with an oil pressure sensor. The control lamp caught fire, do not ignore it. In the future, this can provoke a breakdown of the torque converter.
So, we found out what thehydromechanical gearbox. As you can see, with proper maintenance it will be as reliable as mechanical. In this case, the driver does not have to constantly squeeze the clutch.