Method for controlling RPM of engine in hydraulic construction machine

摘要

A method for controlling the RPM of an engine in a hydraulic construction machine. A reference throttle lever position value and a reference engine RPM value are set to allow the engine to have a target output characteristic. A first control arithmetic operation is performed in response to a present throttle lever position value and the set reference throttle lever position value to allow a difference between the present throttle lever position value and the set reference throttle lever position value to be within the range of a mechanical error of an engine throttle control mechanism. A first control signal is generated as a result of the first control arithmetic operation to control the RPM of the engine. Then, a second control arithmetic operation is performed in response to a present engine RPM value and the set reference engine RPM value to allow the present engine RPM value to be approximated to the set reference engine RPM value under the condition that a difference therebetween is within the range of the mechanical error of the engine throttle control mechanism. A second control signal is generated as a result of the second control arithmetic operation to control the RPM of the engine.