CONSTANTMESH TYPE TRANSMISSION

In this type of transmission, gears on the upper shaft (mainshaft) are kept in idle rotation on the shaft, while being constantly meshed with the mating gears that are fixed to and rotated together with the lower shaft (countershaft), instead of sliding the gears on the shaft to bring them in mesh as seen in the slide-mesh type transmission. A dog clutch is spline-fitted to the upper shaft and is slided sideward to engage with the splined hub on a gear next to the dog clutch. This allows the gear to come into engagement with the shaft through the dog clutch and, in result, the gear and the shaft rotate together. Therefore, shifting the several stages of gear speeds in this type of transmission can-be performed with the dog clutches arranged between the several couples of gears.

Difficulty on the gearshifting we have noted with the slide-mesh type transmission is greatly lessened with the constantmesh type transmission, although noisy shifting may be sometimes still remained if the considerable difference of peripheral velocities exist between the dog clutch and the gear hub when they are engaged with each other.

The below is a five-speed forward, four-speed reverse, constantmesh type transmission, widely in use for the bulldozers. Two separate gearshift levers are used’, one for changing the forward-and-reverse directions and the other for shifting travel speeds.The below is a five-speed forward, four-speed reverse, constantmesh type transmission, widely in use for the bulldozers. Two separate gearshift levers are used’, one changing the forward-and-reverse directions and the other for shifting travel speeds.

   

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.