Patent ID: 11230819

Abstract:
To provide a construction machine that can improve the energy efficiency in a leveling operation in which an arm crowding operation and a boom raising operation are performed simultaneously. A controller (30) controls a first regulator (60a) according to the maximum value among target displacement volume (Qa1) of a first hydraulic pump (1) that is based on a boom raising operation amount (Pi1), and target displacement volume (Qa2) of the first hydraulic pump (1) that is based on an arm crowding operation amount (Pi2) of an arm operation device (18) if the boom raising operation amount (Pi1) of a boom operation device (17) is smaller than a predetermined operation amount, or if a delivery pressure (P2) of a second hydraulic pump (2) is equal to or higher than a predetermined pressure, and controls the first regulator (60a) according only to the target displacement volume (Qa1) of the first hydraulic pump (1) that is based on the boom raising operation amount (Pi1) if the boom raising operation amount (Pi1) is equal to or larger than the predetermined operation amount, and the delivery pressure (P2) of the second hydraulic pump (2) is lower than the predetermined pressure.