Liugong has officially released its new "Direct-Drive" series of large-tonnage wheel loaders, specifically engineered for high-frequency cyclic loading scenarios in mines. Traditional wheel loaders use a "Torque Converter" to transmit engine power to the gearbox. While effective for shock absorption, torque converters suffer from "slippage" (energy loss) during power transmission, especially when the machine is climbing ramps or digging into the pile. This slippage generates significant heat and wastes fuel.
The new Direct-Drive system replaces the torque converter with a "Hydrostatic Drive Unit" (pump-motor combination) directly coupled to the engine flywheel. The core engineering innovation is the "Electronic Anti-Stall Control." In traditional loaders, if the operator floors the accelerator while the bucket is engaged in heavy digging, the engine can stall due to the sudden torque load. The Direct-Drive system uses an ECU to monitor engine RPM. If the RPM drops below the peak torque range, the system automatically reduces the displacement of the hydraulic motor, lowering the torque load on the engine and preventing stalling without the operator lifting the pedal.
Furthermore, the system features "Hydrostatic Braking." When the operator releases the accelerator, the hydraulic motor acts as a pump, pushing fluid back through a relief valve. This provides immense retarding force, significantly reducing the wear on the mechanical service brakes. The system achieves a top speed of 40 km/h, matching traditional machines, but with instant torque response. Field tests in a granite quarry showed a 12% reduction in fuel consumption and a 25% increase in brake lining life compared to conventional torque converter models.
