Overload Detection in Forklift Hydraulic Systems

The system dynamically adjusts the evaluation of load pressure signals based on the current operational state. When the hydraulic system is in heating mode (pump running, valve open, no actual lifting), the controller recognizes this state and temporarily suspends overload evaluation, allowing high pressure readings during heating without triggering false shutdowns. This dynamic state-based adjustment resolves the contradiction between reliable overload detection and system availability for heating.

The system changes the interpretation threshold of load pressure parameters based on operational context. During heating operations, the same load pressure readings that would normally indicate overload are reinterpreted as acceptable heating conditions. The controller modifies the decision logic by changing the parameter evaluation criteria according to the system state, thereby preventing false overload detection while maintaining heating functionality.

The system maintains continuous monitoring of the heating process and automatically terminates it when the desired temperature is reached or when actual lifting operations begin. This prevents unnecessary energy waste by stopping the heating cycle at the appropriate moment, while still allowing rapid heating when needed. The continuous action is maintained only as long as it serves the heating purpose.

The system converts the potentially harmful effect of opening the pressure relief valve during heating into a beneficial feature. The controlled opening of the pressure relief valve during heating operations is intentionally used to generate the necessary pressure differential to circulate hydraulic fluid and heat it up quickly. The harmful pressure loss is transformed into a useful heating mechanism by controlling when and how the valve opens during the heating cycle.

The system uses feedback from multiple sensors (load pressure sensor, mast position sensor, temperature sensor) to continuously monitor system state and make real-time adjustments. The controller receives feedback about current load, mast extension position, and hydraulic temperature, and uses this information to dynamically control the pressure relief valve and evaluate overload conditions. This multi-parameter feedback system enables timely overload protection while maintaining high load capacity.

The system performs preliminary evaluation of load conditions before actual lifting occurs by monitoring pressure build-up trends and comparing them against expected values for different load scenarios. The controller anticipates potential overload conditions by analyzing the rate of pressure increase and mast position changes, and can prevent overload before it becomes critical. This preliminary action enables early intervention while maintaining maximum load capacity for legitimate operations.