Transfer case high-low gear switching protection device and method, and engineering machinery vehicle

Abstract

The invention relates to a transfer case high-low gear switching protection device, a transfer case high-low gear switching protection method and an engineering machinery vehicle. The transfer case high-low gear switching protection device comprises a transfer case low gear switch, a coil and a switch contact of a transfer case low gear detection relay, a transfer case low gear indicator lamp, a transmission neutral gear detection switch, a transfer case low gear detection switch, a transfer case low gear electromagnetic valve, a vehicle speed controller, and a coil and a switch contact of a speed output relay, wherein the vehicle speed controller controls the coil of the speed output relay to be energized or de-energized according to a current vehicle speed value, and the coil of the speed output relay is energized or de-energized to control the switch contact of the speed output relay to turn on the transfer case low gear switch and the transmission neutral gear detection switch or a power supply, so that when the current vehicle speed value is non-zero, the high-low gear switching operation of the transfer case low gear switch is limited. Thus, transfer case high-low gears are prevented from being operated under the condition that the vehicle speed is non-zero, and the risk of tooth beating caused thereby is avoided.

Description

technical field [0001] The invention relates to the field of vehicle electrical control, in particular to a high-low gear switching protection device and method for a transfer case and a construction machinery vehicle. Background technique [0002] The construction machinery vehicle itself is heavy, and generally has 4 to 6 axles, of which 2 to 4 are drive shafts. The power output by the engine needs to be transmitted to these drive shafts through a transfer case. The transfer case is a gear transmission device, which is fixed on the frame alone, and its input end is connected to the output end of the gearbox through a universal transmission. The transfer case has several output ends, which are connected to the drive through the universal transmission Component connections such as shafts or oil pumps. When the drive shaft is connected to the output end of the transfer case, the dynamic performance of the system can be changed by adjusting the speed ratio of the gear set ins...

AI Technical Summary

Problems solved by technology

[0008] figure 1 The scheme shown can switch between the high and low gears of the transfer case when the transmission is in neutral, but when the vehicle is in neutral but still at speed, there is still the risk of switching between the high and low gears of the transfer case.

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