Gearbox Case analysis

In a gearbox, the transmission path is such that power enters the first shaft through couplings, splines, etc. This power is transmitted from the input shaft to the secondary through two engaged gears. Depending on the gear ratio, the gearbox has different numbers of gears and shafts. The mentioned power enters the output shaft through the last gear and exits the last shaft of the gearbox by couplings, pulleys, splines, etc. Gears and shafts are rotating parts and need to be connected to the gearbox housing by bearings. The bearing is responsible for bear the loads and transferring it to the housing. The housing or gearbox casing is also fastened to the chassis.

Gearbox case has basic functions in gearboxes, which include:

• Maintain and support the position of the gears
• Place the lubricant and prevent entering contaminants and foreign objects
• Reduce noise emission and vibrations of gear engagement
• Packing and assembling the components together so that the center of mass is as low as possible

In designing and analyzing the case of a gearbox, factors such as material, geometry, fastening position to the chassis, screws connecting different parts of the case and the loads applied are very important.

The mounting bases must be strong enough to transfer the reaction forces to the mounting chassis and be able to absorb and eliminate shocks. In gearboxes where the motor is mounted directly on the housing, the gearbox housing must also be able to withstand the torque applied by the engine. Some gearbox cases are multi-part and are connected with screws. The use of positioning pins is necessary in such cases and the connected surfaces are machined. Also, some gearbox case are in one piece and Monoblock. In addition to the main parts of a case, covers are also very important in withstanding the forces applied.

In summary, a gearbox housing must be inspected for the following conditions and the requirements must be met:

1. Strength against contact forces in the place of bearings and screws
2. Suitable resistance to deformation in order to maintain the alignment of the shafts
3. Has a proper lubrication and sealing system
4. Low weight
5. Proper manufacturability

Another service of the Gearkade is the design and analysis of the gearbox case. In this process, by applying loads to the case and determining the material for it, the strength of the case is determined in different places and its weaknesses that do not have sufficient safety factor are extracted and strengthened.

Also, by determining the deformation of different parts of the case, the areas whose deformation disturbs the performance of the two-gear engagement are found and strengthened. Exaggerated images of the case show a better view of what happened in the design.

In addition to the above, it is possible to analyze the gearbox case in terms of vibrations, and by analyzing the vibrational frequencies, changes can be made to improve the vibration of the gearbox case.

Another important analysis of the gearbox case is the temperature analysis of different points. With this study, changes can be made in places where the temperature is higher than the allowable limit to improve the thermal of the gearbox case. In such a report, which can also be displayed graphically, the increase in temperature at the bearings is quite obvious and can be improved.

In Gearkade design of Gears, shafts and bearings are performed, and gearbox cases are determined and comprehensive analyzes of their strength, deformation, temperature and vibrations are performed.