Manual method of gear shifting is still widely used in cars. The mechanical box of gear shifting is intended for change of torque of the engine. This knot of the car received the name because of the corresponding mechanical nature of control of the switching device.
Instruction
1. The mechanical transmission has the step device as torque in it changes not smoothly, and steps. One step is the two gear wheels connected among themselves. All steps transfer the rotating effort with accurately established speed which is defined by transfer number. Understand the relation of quantity of teeths of the conducted gear to number of these elements at the leader as it.
2. Transmissions on number of steps are divided into four-, five-step and so on. In modern cars mechanical boxes with five steps are most often used. These devices can also incorporate two or three shafts. Two shafts in a box can be met on cars with the front drive. Three shafts are applied generally by rear-driven cars.
3. The mechanical scheme of the most popular transmission of three-shaft type includes primary (leading), intermediate and secondary (conducted) shafts. On shafts place a set of gear wheels together with devices for synchronization. Also the mechanism of change of transfers is a part of a box. All details are established in the case called a case.
4. Connection with coupling is reached at the expense of the leading shaft which has vents for a clutch plate and the corresponding gear wheel for torque transmission. Parallel to a main shaft in a three-shaft box is located intermediate, supplied with the block of gears. The secondary shaft is on one axis with primary for what the bearing installed from a face is used. Gears of the conducted and intermediate shafts are in reliable gearing.
5. The synchronizers which are strictly linked to the conducted shaft help to level angular speeds of gears between shafts. These devices have special vents, and therefore can move in the longitudinal direction. As a rule, supply with synchronizers all transfers of boxes of mechanical type.
6. Directly on the case of a box the mechanism of switching of steps usually fastens. It consists of forks, sliders and a control lever. To prevent simultaneous inclusion of different transfers, the blocking device is used. In modern mechanical boxes control of process of switching can be remote.
7. The case unites all elements of the mechanical scheme, protecting them from damages and hit of foreign objects. It is required also for storage of lubricant substances. The most reliable cases of mechanical transmissions produce from magnesian or aluminum alloy.