Abstract: A control system for construction machinery, includes a hydraulic pump, first and second actuators connected to the hydraulic pump through first and second parallel lines respectively, first and second control valves installed in the first and second parallel lines respectively and configured to control operations of the first and second actuators, first and second spool displacement adjusting valves configured to control displacement amounts of the spools of the first and second control valves, and a control valve control portion configured to output the control signal, and configured to limit a maximum allowable value of the manipulation signal for the first actuator to a value selected by the operator and limit a spool displacement amount of the second control valve according to the limited manipulation signal for the first actuator when the manipulation signal for a multiple operation of the first and second actuators is received.

Abstract: The present disclosure relates to a hydraulic system of construction machinery and a method of controlling the hydraulic system. The hydraulic system of construction machinery and the method of controlling the hydraulic system according to the present disclosure assign a weighted value for each operation, preliminarily distribute a (available torque that can be used) value that an engine can provide, through torque weighted values for each operation, and calculate surplus torque and deficient torque by comparing a preliminary distributable torque value to required torque. The surplus torque is provided for an operation in which torque is deemed to be deficient. Thus, the hydraulic system of construction machinery and the method of controlling the hydraulic system according to the present disclosure can sufficiently use available torque that can be used so that an operator can achieve a desired level of performance during the operation.

Abstract: Disclosed are a device and a method for controlling a hydraulic pump in a construction machine, the method including: checking whether a dynamic characteristic of an engine deviates from a predetermined permissible range when a load is applied to the hydraulic pump and a pump load reaches pump torque required by the hydraulic pump; when the dynamic characteristic of the engine deviates from the predetermined permissible range, applying a pump load to the hydraulic pump so as to increase the pump torque to predetermined torque with a predetermined change rate; collecting information which is generated when the pump load is applied; generating a new torque change rate map by generating a torque change rate for each load section based on the information collected in the information collecting step; and updating an existing torque change rate map to the new torque change rate map generated in the map data generating step.

Abstract: Disclosed are a construction machine and a method of controlling a construction machine. The construction machine includes: a first pump and a second pump; an engine which provides available torque to the first pump and the second pump; a first joystick and a second joystick which control actuators operated by a working fluid discharged from the first pump and the second pump; a joystick operation amount acquiring unit which acquires operation amounts of the first joystick and the second joystick; and a control unit which adjusts a torque distribution ratio with respect to the first pump and the second pump in accordance with the operation amounts of the first joystick and the second joystick when a sum of required torque of the first pump and required torque of the second pump is higher than the available torque.

Abstract: A control system for construction machinery includes a first hydraulic pump, first and second actuators connected to the first hydraulic pump through first and second hydraulic lines respectively, first and second control valves installed in the first and second hydraulic lines respectively and configured to control operations of the first and second actuators, and a controller configured to adjust a spool displacement amount of the first control valve according to an amount of working oil to be supplied to the first actuator when the first actuator performs a single or multiple operation by self-load.

Abstract: In a method of controlling a main control valve of an excavator, when speeds of a boom cylinder and an arm cylinder is increased by handling a boom joystick and an arm joystick, a second arm control spool between a first hydraulic pump and the arm cylinder may be closed. A first boom control spool between the first hydraulic pump and the boom cylinder may be opened to supply a first flux generated from the first hydraulic pump to the boom cylinder. A second boom control spool between a second hydraulic pump and the boom cylinder may be closed. A first arm control spool between the second hydraulic pump and the arm cylinder may be opened to supply a second flux generated from the second hydraulic pump to the arm cylinder.

Abstract: The present disclosure relates to an apparatus for controlling a hydraulic pump for a construction machine. The apparatus for controlling the hydraulic pump for the construction machine according to the present disclosure includes: a hydraulic pump control device configured to generate first and second pump commands for controlling first and second hydraulic pumps so that the first and second hydraulic pumps generate pump torque corresponding to a request value; and a torque controller configured to generate first and second corrected pump commands, which are the corrected first and second pump commands, by a torque inclination map generated by reflecting a dynamic characteristic of an engine, and to provide the first and second corrected pump commands to the first and second hydraulic pumps.

Abstract: Disclosed are a hydraulic system for construction equipment and a method of controlling the same, and the hydraulic system for construction equipment includes: a plurality of pressure control-type hydraulic pumps driven by an engine provided in construction equipment; an actuator driven by working oil discharged from the hydraulic pump; a closed center-type main control valve provided between the hydraulic pump and the actuator, and bypassing a virtual flow rate; and a controller configured to control the hydraulic pump by receiving the bypassed virtual flow rate from the main control valve.

Abstract: The present disclosure relates to a hydraulic system for a construction machine, and more particularly, to a hydraulic system for a construction machine including a plurality of actuators, in which each of the actuators includes a pump/motor, is operated under a control of a corresponding pump/motor, and stores working oil in an accumulator or receives the working oil supplemented from the accumulator in accordance with a difference between a flow rate entering the actuator and a flow rate discharged from the actuator.

Abstract: The method for controlling the hydraulic system of construction machinery according to the present disclosure includes an engine speed prediction step, in which a variable rated engine speed, which varies within a range larger than a fixed rated engine speed and smaller than a high idle engine speed for the fixed rated engine speed and a virtual engine speed, which is to be input later, are predicted to output a virtual engine speed value predicted before an actual engine speed is input. Accordingly, when an operation load is applied, pump torque may initially have a margin, and even though an engine speed is decreased due to the operation load, it is possible to prevent an engine speed decrease phenomenon in which the engine speed becomes remarkably smaller than the rated engine speed.

Abstract: In a method of controlling a main control valve in construction machinery, a first joystick signal for controlling a first control valve device and/or a second joystick signal for controlling a second control valve device are received from one joystick. While one of the first and second control valve devices operates, whether or not a joystick signal for controlling another of the first and second control valve devices is inputted is determined. A weighted value is applied to a threshold of valve operation initiation with respect to a joystick displacement to determine a raised threshold of valve operation initiation. If the inputted joystick displacement satisfies the raised threshold of valve operation initiation, a valve stoke corresponding to the inputted joystick displacement is calculated and outputted.

Abstract: The present disclosure relates to a hydraulic system for construction equipment, and more particularly, to a hydraulic system, in which an actuator is controlled by a pump/motor. The hydraulic system for construction equipment according to the present disclosure includes logic valves in first and second hydraulic lines provided to an actuator, respectively, and when it is desired to operate the actuator in a state where an operation of the actuator is stopped by closing the logic valves, a pressure difference may be resolved by increasing pressure in sections of a pump/motor and the logic valves in advance even if a load is applied to the actuator, and thus the actuator may implement a desired operation without being affected by the load. That is, it is possible to improve operation controllability of the actuator.

Abstract: An exemplary embodiment of the present specification relates to an apparatus for controlling a hydraulic pump for an excavator with respect to a change of an operation mode, the apparatus including: an operating unit configured to generate an operation signal according to an operation of an operator, and including a joystick or a pedal; an oil flow supplying unit configured to supply oil to actuators, in order to drive a plurality of actuators corresponding to the operation signal, and including a plurality of pumps and a plurality of logic valves; and a control unit configured to control the oil flow supplying unit by using a priority algorithm for each operation considering a use frequency and a load of the actuator with respect to a change of a predetermined operation mode according to the operation signal.

Abstract: The present disclosure relates to a hydraulic system of construction machinery and a method of controlling the hydraulic system. The hydraulic system of construction machinery and the method of controlling the hydraulic system according to the present disclosure assign a weighted value for each operation, preliminarily distribute a (available torque that can be used) value that an engine can provide, through torque weighted values for each operation, and calculate surplus torque and deficient torque by comparing a preliminary distributable torque value to required torque. The surplus torque is provided for an operation in which torque is deemed to be deficient. Thus, the hydraulic system of construction machinery and the method of controlling the hydraulic system according to the present disclosure can sufficiently use available torque that can be used so that an operator can achieve a desired level of performance during the operation.

Abstract: Disclosed are a hydraulic system for construction equipment and a method of controlling the same, and the hydraulic system for construction equipment includes: a plurality of pressure control-type hydraulic pumps driven by an engine provided in construction equipment; an actuator driven by working oil discharged from the hydraulic pump; a closed center-type main control valve provided between the hydraulic pump and the actuator, and bypassing a virtual flow rate; and a controller configured to control the hydraulic pump by receiving the bypassed virtual flow rate from the main control valve.

Abstract: The present disclosure relates to a hydraulic system for a construction machine which uses an electric hydraulic pump, and more particularly, to a hydraulic system including an emergency control unit for temporarily driving the construction machine when an electronic control unit controlling the electric hydraulic pumps fails to operate.

Abstract: The present disclosure relates to a hydraulic system for a construction machine having an electronic hydraulic pump, and more particularly, to a hydraulic system which temporarily drives the construction machine when an operation of an electronic control unit controlling an electronic hydraulic pump is abnormal, particularly, when the electronic control unit is not able to perform a control because an operative amount of a joystick input to the electronic control unit is not normally transmitted to the electronic control unit.

Abstract: The present disclosure relates to a method for controlling a hydraulic system of construction machinery. The method for controlling the hydraulic system of construction machinery according to the present disclosure includes an engine speed prediction step, in which a variable rated engine speed, which varies within a range larger than a fixed rated engine speed and smaller than a high idle engine speed for the fixed rated engine speed and a virtual engine speed, which is to be input later, are predicted to output a virtual engine speed value predicted before an actual engine speed is input. Accordingly, when an operation load is applied, pump torque may initially have a margin, and even though an engine speed is decreased due to the operation load, it is possible to prevent an engine speed decrease phenomenon in which the engine speed becomes remarkably smaller than the rated engine speed.

Abstract: The present disclosure relates to an apparatus for controlling a hydraulic pump for a construction machine. The apparatus for controlling the hydraulic pump for the construction machine according to the present disclosure includes: a hydraulic pump control device configured to generate first and second pump commands for controlling first and second hydraulic pumps so that the first and second hydraulic pumps generate pump torque corresponding to a request value; and a torque controller configured to generate first and second corrected pump commands, which are the corrected first and second pump commands, by a torque inclination map generated by reflecting a dynamic characteristic of an engine, and to provide the first and second corrected pump commands to the first and second hydraulic pumps.

Abstract: Disclosed are a device and a method for controlling a hydraulic pump in a construction machine, the method including: checking whether a dynamic characteristic of an engine deviates from a predetermined permissible range when a load is applied to the hydraulic pump and a pump load reaches pump torque required by the hydraulic pump; when the dynamic characteristic of the engine deviates from the predetermined permissible range, applying a pump load to the hydraulic pump so as to increase the pump torque to predetermined torque with a predetermined change rate; collecting information which is generated when the pump load is applied; generating a new torque change rate map by generating a torque change rate for each load section based on the information collected in the information collecting step; and updating an existing torque change rate map to the new torque change rate map generated in the map data generating step.