The transmission consists of two parts: a torque converter 3 and a gearbox 4. One end of the torque converter is directly connected to the diesel engine, and the other end is directly connected to the gearbox 4. This compact structure and reliable connection is currently the most commonly used and most common connection method for wheel loaders at home and abroad. Others include the transmission as a whole separate from the diesel engine, or the torque converter is directly connected to the diesel engine but separately from the gearbox, and the transmission shaft is connected between them.
The transmission is composed of a twin-turbo hydraulic torque converter and a planetary power shift transmission. The gearbox has two planetary rows, one forward and one backward, plus a direct gear (II gear), for a total of two forward and one reverse three gears. The structure is simple, the gears are few, and the single-lever operation is completely realized. The torque converter has two turbines, and the two turbines are directly transmitted to the input shaft (gear) of the gearbox, which is a light-load transmission state for each gear. One turbine is transmitted to the input shaft of the gearbox through the overrunning clutch. When the torque of each corresponding gear increases and the speed decreases until the overrunning clutch is combined, the two turbines participate in the work at the same time, which is the low-speed and high-torque state of the corresponding gear. It is automatically realized by the speed of the overrunning clutch. In fact, the transmission has 4 forward gears and 2 reverse gears, because each gear has a high and low speed automatic shift. Therefore, the transmission shows its advantages in this respect, and has better maneuverability than ordinary multi-speed and multi-lever transmissions. But it also has a major disadvantage. The twin-turbo torque converter is less efficient than a simple three-element torque converter and has a greater power loss. At present, such fixed-shaft gearboxes have not yet adopted electronic technology, so they are all operated by ordinary multiple levers.
The current third-generation products, such as Liugong’s ZL50G, use a three-element torque converter produced by the "ZF" company and a four-speed forward, three-reverse fixed-shaft transmission. The three-element torque converter has high efficiency. It adopts single-handle electro-hydraulic gear shift controlled by a microcomputer semi-automatically, and a quick switch button (KD button) for I and II gears is added during operation. Each operating cycle only needs to move the handle back and forth once and press the KD button once, which is simple, fast, comfortable and labor-saving to operate, thereby greatly improving the operating efficiency. The selection of this product lies in its variable speed control system.
automatic tray loading machine