Introduction Of Heavy Truck Gearbox

Introduction to Heavy Truck Gearbox

Sinotruk’s new gearbox is a new structure Heavy Truck Gearbox developed by China heavy truck group company by absorbing the advanced technology of mature Heavy Truck Gearbox at home and abroad, which has the characteristics of simple structure, reliable performance and low failure rate.

The gearbox is divided into 9 gears and 16 gears, a total of 24 variants, according to the clutch separation method is divided into push type and pull type two;According to the Heavy Truck Gearbox control mechanism is divided into single rod and double rod two kinds, in which the single rod is used for shift straight pull rod operation, double rod for soft shaft operation;
According to the output flange is divided into 165 flat Φ and Φ 180 end tooth two;According to whether there is a force extractor is divided into force extractor with and without force extractor two.
The transmission consists of a front-facing 5-speed main Heavy Truck Gearbox and a rear-mounted secondary transmission.
The main transmission adopts double shaft structure, the auxiliary transmission adopts planetary gear mechanism, the main transmission is manually operated, and the auxiliary transmission is pneumatic operated, with 9 forward gears and 1 reverse gears.In the main transmission, one shaft (input shaft) and one shaft gear are connected by splines (see Figure 1), and two shafts (main shaft) are connected.

Heavy Truck Gearbox Assembly

The main box of the Heavy Truck Gearbox adopts sliding meshing sleeve for shifting, and the auxiliary box adopts the internationally popular lock ring synchronizer.
The synchronizing ring of the synchronizer adopts the form of steel-based molybdenum spray, which has the characteristics of large friction force and long service life.
A 16-gear transmission is a differential transmission added at the front end of the Heavy Truck Gearbox, which is equivalent to adding a two-gear front auxiliary transmission.There is a preselective valve handle on the gearbox shift ball head.
Press or lift the preselective valve handle according to the road conditions before shifting, and then step on a foot to clutch, then you can change to the corresponding gear.With a 16-speed transmission, the engine can easily work in the low fuel consumption area.

How Work Of Heavy Truck Gearbox

The gearbox assembly in a heavy truck is a critical component responsible for transmitting power from the engine to the wheels while allowing the driver to select different gears for various driving conditions. Here’s how it works:

Input Shaft: The gearbox assembly begins with the input shaft, which is connected to the engine’s crankshaft. As the engine rotates, it transfers rotational power to the input shaft.
Gear Sets: Inside the gearbox, there are multiple gear sets arranged in different configurations. These gear sets consist of gears of varying sizes, known as pinions and gears, which mesh together to transmit power.
Gear Selection: The driver selects the desired gear ratio using the gear shift lever or selector mechanism inside the cab. This action engages different gear sets within the gearbox to achieve the desired speed and torque output.
Clutch Mechanism: In manual transmission trucks, a clutch mechanism is used to disengage the gearbox from the engine during gear changes. When the clutch pedal is depressed, it disengages the clutch, allowing the driver to shift gears smoothly. Releasing the clutch pedal re-engages the clutch, transmitting power from the engine to the gearbox again.
Output Shaft: The output shaft is connected to the differential, which distributes power to the truck’s wheels. As the gears inside the gearbox rotate, they transfer power from the input shaft to the output shaft, adjusting the speed and torque output as needed based on the selected gear ratio.
Synchronization: In modern transmissions, synchronization mechanisms ensure smooth gear shifting by matching the speeds of the gears before engagement. This minimizes wear and tear on the gearbox components and provides a smoother driving experience.
Overdrive and Underdrive: Some heavy truck gearboxes may also feature overdrive and underdrive gears, which allow for higher or lower gear ratios than standard gears. These additional gear options provide flexibility for driving in different conditions, such as highway cruising or heavy hauling.

Overall, the gearbox assembly in a heavy truck plays a crucial role in translating engine power into vehicle motion while providing the driver with control over speed and torque output. Proper maintenance and care of the gearbox are essential to ensure smooth operation and longevity of the truck’s drivetrain system.