Patent ID: 8567549
Filing Date: 2013-10-29
Classification: B60K,B60L,B60W,E02F,F15B,F16H,Y02T,Y10T

Abstract:
1. A system for controlling engine revolutions for a hybrid construction machine, including an engine, a hydraulic pump which is driven by the engine to drive a hydraulic actuator with discharged hydraulic fluid, a motor-generator which is driven by the engine to generate electricity and to drive the hydraulic pump as a motor supplementing the engine, and an energy storage device which is charged with electric energy generated by the motor-generator and which supplies the electric energy for motor operation of the motor-generator, the system comprising: a torque detection means for detecting an output torque of the hydraulic pump that is required to drive the hydraulic actuator; and hybrid control means for receiving feedback from the torque detection means and for determining from the feedback if a change of output torque of the hydraulic pump exceeds a predetermined level that will cause an unwanted drop in revolution of the engine to occur and, if so, for controlling the motor-generator to supplement output of the engine to prevent the drop.