Third gear

Third gear

The gearbox input shaft E rotates in a clockwise direction.

The crownwheels K1 and K2 are coupled to the input shaft E by the engagement of the clutch C1, clutch carrier drum D and the clutches C3 and C0.

The clutch C3 locks the free wheel F0.

The epicyclic gear sets P1 (S1 - ST1 - K1) and P2 (S2 - ST2 - ST3 - K2) lock onto each other when their transmission ratios are different.

The planet gears ST1, ST2 and ST3, locked, drive the gear train carrier T1 in a clockwise direction at the same speed as the input shaft E (ratio 1:1).

The gear I1 transmits motion to the wheels via the gear I2 and the differential relay shaft U.

Fourth gear

The gearbox input shaft E rotates in a clockwise direction.

The crownwheel K2 is coupled to the input shaft E by the engagement of the multiple disc clutch C1, the clutch carrier drum D and the clutch C0.

The free wheel F0 allows the crownwheel K1 to rotate in a clockwise direction.

The sun gear S2 is locked on the gearbox casing by the engagement of the band brake B1.

The planet gears ST2, driven by the crownwheel K2 via the planet gears ST3, shift onto the locked sun gear S2, rotating the gear train carrier T1 in a clockwise direction.

The clockwise shift of the gear train carrier T1 makes the planet gears ST2 rotate in a clockwise direction on the locked sun gear S2 and the planet gears ST3 in an anti-clockwise direction.

The anti-clockwise rotation of the planet gears ST3 on the crownwheel K2 achieves a further increase in clockwise rotation of the gear train carrier T1.

The result is that the speed of the gear train carrier T1 and the gear I1 is higher than that of the driving crownwheel K2, obtaining 4th gear.