Operation of the CTX automatic transmission
Pic. 12.9. Stepless automatic transmission CTX: 1 - steel multi-link tape; 2 - a pair of secondary conical disks; 3 - downshift; 4 - compensating gear; 5 - speedometer drive; 6 - main gear; 7 - planetary gear; 8 - drive shaft; 9 - reverse gear clutch; 10 - forward gear clutch; 11 - a pair of primary conical disks
The distinguishing feature of the CTX automatic transmission is its steel multi-link belt: it transmits the power from the engine between two axially adjustable conical discs not by traction, but by sliding (pic. 12.9). The steel multi-link belt consists of hundreds of high-strength steel links with an extremely wear-resistant surface. The transmission connects the input (primary) gearbox shaft with output (secondary) shaft of the gearbox, while it moves in pairs, in front of each other, conical discs (tapered steel chain discs). Depending on the road situation, the discs are hydraulically pressed against each other and moved apart. In response to pressure differences, the steel strip moves lower into the pair of tapered discs of the input shaft, for example, at the beginning of a vehicle movement. Because of this, its radius on the input shaft becomes smaller if the tape moves on a pair of conical disks «up» - its radius becomes larger.
How the CTX Automatic Transmission Changes Gear Ratio
1. The small belt radius on the primary conical discs and the large belt radius on the secondary conical discs result in the maximum gear ratio required for smooth starting of the vehicle.
2. The large belt radius on the primary conical discs and the small belt radius on the secondary cone discs result in the lowest gear ratio for optimum engine speed for highway driving.
3. In the range of these gear ratios, an infinite number of gear ratios are possible. At the same time, the hydraulic control unit of the CTX gearbox automatically selects a gear ratio in which the engine always works with the best efficiency.
4. The transmission of torque when starting off is transmitted by a hydraulic multi-plate clutch. As with all existing automatic transmissions, it tends to creep/sluggish. As soon as the crankshaft of the engine increases the speed, the clutch is disengaged and further drive is carried out without jerks in the system of conical discs.
5. For forward and reverse movement, a single-stage planetary gear is located between the engine flywheel and the conical disc system. Depending on the position of the gear selector, it determines the direction of movement.
6. Moving forward «forward gear clutch» connected to the power circuit of the planetary gear and the input shaft. So without mechanical losses, the planetary gear rotates as a single unit.
7. Reverse enabled «reverse gear clutch» with a force lock, it securely fixes the wheel with internal planetary gear teeth, while the planetary gears rotate the sun wheel located on the shaft of the primary conical disks in the direction of reverse rotation.
PRACTICAL ADVICE
Features of the operation of the automatic transmission CTX Fiesta
After repair, never start the engine with a gearbox without working fluid - the steel multi-link belt and conical discs will run dry, which will lead to their intense wear. If the battery of a Fiesta with CTX automatic transmission is dead, it is not possible to start the engine by towing the vehicle: when the engine is not running, the hydraulic clutch does not connect the engine crankshaft to the gearbox. You can start the engine only from the battery of another car. Therefore, there should always be a set of wires in the trunk.
When towing, first set the selector lever to the position «N»
If it is necessary to tow a Fiesta with an automatic CTX transmission, be sure to set the selector lever to the position «N», the maximum towing speed must not exceed 50 km/h. Vehicles with automatic transmission cannot be towed more than 80–100 km because the drive lubrication is insufficient. In doubtful cases, it is necessary to transport the car on a platform.
Visitor comments