Abstract: A method is provided for compensating for the flow rate of a variable capacity-type hydraulic pump such that, when a manipulation lever is manipulated, a discontinuous section, which has no change in the discharge flow rate of the hydraulic pump, is eliminated.

Abstract: A method is provided for compensating for the flow rate of a variable capacity-type hydraulic pump such that, when a manipulation lever is manipulated, a discontinuous section, which has no change in the discharge flow rate of the hydraulic pump, is eliminated.

Abstract: A priority function control apparatus for a construction machine and a control method thereof are disclosed, which enable an operator to set the order of preference or the extent of preference of an optional device in the case where a work is done through replacement of the optional device attached to an excavator.

Abstract: An apparatus and method for controlling a control valve, and a method for controlling a discharge flow rate of a hydraulic pump for a construction machine are disclosed, which can control a spool shifting speed of a directional valve and a discharge flow rate of a hydraulic pump in accordance with a hydraulic fluid temperature in winter season with below zero temperatures.

Abstract: Disclosed is a system for controlling a hydraulic pump in a construction machine which can reduce the discharge flow of the hydraulic pump in proportion to the load pressure of the hydraulic pump to enhance operability by the driver. The present invention provides the system for controlling the hydraulic pump in the construction machine, which is characterized by detecting the discharge pressure of the hydraulic pump and the operation activity of an operation lever, and comparing the detected discharge pressure of the hydraulic pump and a predetermined pressure value, and when the detected discharge pressure exceeds the predetermined pressure value, the maximum dischargeable flow of the hydraulic pump is reduced in proportion to the difference between the detected pressure and the predetermined pressure value.

Abstract: Disclosed is a method of controlling the flow rate of a hydraulic pump, which controls the discharge flow rate in proportion to a manipulated amount of a manipulation lever operated by a user even when the discharge pressure of the hydraulic pump is varied.

Abstract: A hydraulic pump control system provided in a construction machine such as an excavator is provided. According to the hydraulic pump control system, a loss of a flow rate is reduced by initially supplying hydraulic fluid as much as necessary from a hydraulic pump to a hydraulic motor in order to accelerate a swing movement of an upper frame against a lower traveling structure or to make an upper swing structure swing.

Abstract: A priority function control apparatus for a construction machine and a control method thereof are disclosed, which enable an operator to set the order of preference or the extent of preference of an optional device in the case where a work is done through replacement of the optional device attached to an excavator.

Abstract: A hydraulic system for a construction machine is provided, which enables a user to set or release a preferential function when an excavation work or leveling work using an excavator is performed.

Abstract: A flow control system for a hydraulic pump of a construction machine that can variably control a discharge flow rate of the hydraulic pump in accordance with load pressure generated by a hydraulic actuator. According to the system, the discharge pressure of the hydraulic pump and the operation rate of the operation lever for the hydraulic actuators is detected, and standard load pressures of the respective hydraulic actuators are set. If the discharge pressure of the hydraulic pump is higher than preset load pressures of the hydraulic actuators, the discharge flow rate of the hydraulic pump is reduced in proportion to the operation rate in accordance with degrees of loads generated by the hydraulic actuators. If the discharge pressure of the hydraulic pump is lower than the standard load pressures of the hydraulic actuators, the discharge flow rate of the hydraulic pump is controlled in proportion to the operation rate.

Abstract: Disclosed is a method of controlling the flow rate of a hydraulic pump, which controls the discharge flow rate in proportion to a manipulated amount of a manipulation lever operated by a user even when the discharge pressure of the hydraulic pump is varied.

Abstract: The present invention pertains to a hydraulic pressure control device of a variable displacement type hydraulic pump for construction equipment, wherein operable sections of operation systems are formed in a wide manner while the hydraulic pump discharges a relatively small flow rate compared with the operation amount of the respective operation systems in the case of complex operations, so as to improve the pressure loss and the fuel ratio of the hydraulic pump. The device includes a flow rate controller, which is preferably connected to an operation amount detecting means and a swash plate control device, and receives operation signals from the operation system of a control device that are detected by the operation amount detecting means so as to control the discharge flow rate of the hydraulic pump.

Abstract: Disclosed is a system for controlling a hydraulic pump in a construction machine which can reduce the discharge flow of the hydraulic pump in proportion to the load pressure of the hydraulic pump to enhance operability by the driver. The present invention provides the system for controlling the hydraulic pump in the construction machine, which is characterized by detecting the discharge pressure of the hydraulic pump and the operation activity of an operation lever, and comparing the detected discharge pressure of the hydraulic pump and a predetermined pressure value, and when the detected discharge pressure exceeds the predetermined pressure value, the maximum dischargeable flow of the hydraulic pump is reduced in proportion to the difference between the detected pressure and the predetermined pressure value.

Abstract: A hydraulic pump control system provided in a construction machine such as an excavator is provided. According to the hydraulic pump control system, a loss of a flow rate is reduced by initially supplying hydraulic fluid as much as necessary from a hydraulic pump to a hydraulic motor in order to accelerate a swing movement of an upper frame against a lower traveling structure or to make an upper swing structure swing.

Abstract: A flow control system of a hydraulic pump for a construction machine is provided, which can variably control a discharge flow rate of the hydraulic pump in accordance with load pressure generated by a hydraulic actuator such as a boom cylinder. According to the flow control system of a hydraulic pump, the discharge pressure of the hydraulic pump and the operation rate of the operation lever for the hydraulic actuators is detected, and standard load pressures of the respective hydraulic actuators are set.