Assessment of the Economic Effectiveness of Optimizing the Transmission of Setra S 417 Passenger Buses

The creation and implementation of technologies aimed at increasing fuel efficiency is becoming the focus of attention of car manufacturers. This may involve improving engines, using less dense materials to build cars, developing efficient transmissions, and implementing alternative energy sources. Changing the gear ratio of the main gear affects the force and speed of rotation of the car's wheels. When reducing the gear ratio (using a higher gear), the torque increases, but the speed of rotation of the wheels, which is used to overcome large obstacles or climb, decreases. Conversely, increasing the gear ratio (using a lower gear) decreases torque but increases wheel speed, resulting in higher speeds on flat surfaces. The effect of changing the gear ratio on fuel performance can be a bit complex. Basically, using a lower gear ratio (higher gear) can help save fuel at high speeds or when driving on level roads, because the engine can run more efficiently at lower rpm. However, in mountain conditions or when driving at low speeds, when more torque is needed, using a higher gear can result in more fuel consumption. The article proposes the reconstruction of the transmission, by replacing the gears of the main transmission, in order to change the gear ratio of the transmission of the Setra S 417 type passenger bus. The vehicle under study is operated at the "TRAVELBUS TERNOPIL" transport enterprise The traction-speed calculation of a bus with a unified transmission was carried out, the fuel-economical characteristic was calculated, and a reduction in the average consumption of fuel and lubricants was established. The effectiveness of the conducted unification was tested in different directions, and it was established that the greatest efficiency was achieved on the expressway. Such unification is not advisable on routes with mountainous terrain.