Transmission arrangement e.g. for tractor or construction machine

摘要

The gear transmission comprises a power shift gearbox (1) and a load shifting gearbox (2), with the latter providing direction change under different gear ratios. The clutches (12, 13) for the load shifting gearbox are hydraulically operated and have an additional control mode to momentarily disengage the clutch during the gear change in the power shift gearbox. This improvement is applied via a control switch (19) on the gearshift (8), pressed by the driver to ensure smooth gear change at higher speeds e.g. when travelling along roads. The additional control mode only applies to the higher gear ratios and is blocked for the lower ratios. It is only operated when the switch is pressed. The length of time the clutches are disengaged is preset and is independent of the length of time the switch is pressed. The control is a once only operation and is linked to the gear shift operation.