ABSTRACT
A synchromesh mechanism is needed because the teeth of the dog clutches would clash if they met at different speeds.
A synchromesh mechanism is needed because the teeth of the dog clutches would clash if they met at different speeds. The system works like a friction-type cone clutch. The collar is in two parts and contains an outer toothed ring that is spring-loaded to sit centrally on the synchromesh hub. When the outer ring (synchroniser sleeve) is made to move by the action of the selector mechanism, the cone clutch is also moved because of the locking keys. The gear speeds up as the cones touch, thus allowing the dog clutches to engage smoothly. A baulking ring is fitted between the cone on the gear wheel and the synchroniser hub. This is to prevent engagement until the speeds are synchronised (Figure 9.5).
