19-07-2014, 04:04 PM
Constant mesh Gearbox
Transmission
The word transmission means the mechanism that transmits the power from the engine crank shaft to the rear wheels.
Constant mesh gearbox
All the gear are in constant mesh with the corresponding gears on the layshaft. The gears on the splined main shaft are free
The dog clutch are provided which are free to slide on the main shaft.
The gears on the lay shaft are fixed.
Double Declutching with Constant mesh Gearbox
For the smooth engagement of the dog clutches it is necessary that the speed of the clutch shaft, layshaft and main shaft gear must be equal.
Therefore to obtain lower gear, the speed of clutch shaft, layshaft and the main shaft gear must be increased.
By Double declutching this can be done.
Advantage of Constant mesh Gearbox over Sliding mesh Gearbox
Wear of dog teeth on engaging and disengaging is reduced because here all the teeth of the dog clutches are involved compared to only two or three teeth in the case of sliding gears.