3.2.1. General information

The transmission will transform a torque transferred from the engine, on size and the direction. It is necessary for ensuring optimum speed and passableness of the car, high profitability of operation of the engine and car movement by a backing. Besides, the transmission separates the engine and transmission during a stop and car parking, and also at its movement by inertia with working engine.

All models with mechanical transmission are equipped with a five-speed transmission united in one knot with differential and the main transfer. The torque from the engine is transferred through a transmission and the main transfer to differential which, in turn, distributes it between power shafts.

The five-step mechanical transmission is equipped with the mechanism of synchronization of all transfers.

Fig. 3.24. Cross-section section of a mechanical transmission of the Mazda 3 car: 1–leading gear wheel of the 1st transfer; 2–leading gear wheel of the 2nd transfer; 3–leading gear wheel of the 3rd transfer; 4–leading gear wheel of the 4th transfer; 5–leading gear wheel of the 5th transfer; 6–backing gear wheel; 7–a conducted gear wheel of the 1st transfer; 8–a conducted gear wheel of the 2nd transfer; 9–a conducted gear wheel of the 3rd transfer; 10-a conducted gear wheel of the 4th transfer; 11-a conducted gear wheel of the 5th transfer; 12-synchronizer coupling (backing gear wheel); 13-intermediate gear wheel of a backing; 14-differential

Fig. 3.25. A transmission in the block with the main transfer: 1–epiploon (differential); 2–sensor of a speedometer of the car; 3–a mechanical transmission in the block with the main transfer; 4–switching mechanism; 5–transmission oil