Construction Machine

A construction machine comprising:

• a first engine;
• a second engine;
• a plurality of bidirectionally variable displacement first hydraulic pumps driven by the first engine;
• a plurality of bidirectionally variable displacement second hydraulic pumps driven by the second engine;
• a plurality of hydraulic actuators;
• an operation device for instructing operation amounts of the plurality of hydraulic actuators;
• a plurality of selector valves selectively connecting the plurality of first hydraulic pumps and the plurality of second hydraulic pumps to any one of the plurality of hydraulic actuators;
• and
• a controller controlling the plurality of first hydraulic pumps, the plurality of second hydraulic pumps, and the plurality of selector valves according to an input from the operation device, wherein
• the controller includes
• an engine load computing section that computes a total of estimated maximum demanded power of first hydraulic pumps connected to the plurality of hydraulic actuators among the plurality of first hydraulic pumps as an estimated maximum load on the first engine, and that computes a total of estimated maximum demanded power of second hydraulic pumps connected to any of the plurality of hydraulic actuators among the plurality of second hydraulic pumps as an estimated maximum load on the second engine,
• an actuator/engine allocation computing section that, at a time of connecting first or second hydraulic pumps that are not connected to any of the plurality of hydraulic actuators among the plurality of first hydraulic pumps and the plurality of second hydraulic pumps to any one of the plurality of hydraulic actuators, allocates second hydraulic pumps that are not connected to any of the plurality of hydraulic actuators among the plurality of second hydraulic pumps to the one hydraulic actuator in a case in which the estimated maximum load on the first engine is heavier than the estimated maximum load on the second engine, and allocates first hydraulic pumps that are not connected to any of the plurality of hydraulic actuators among the plurality of first hydraulic pumps to the one hydraulic actuator in a case in which the estimated maximum load on the second engine is heavier than the estimated maximum load on the first engine, and
• a command generation section that generates command signals to the plurality of first hydraulic pumps, the plurality of second hydraulic pumps, and the plurality of selector valves according to a computing result of the actuator/engine allocation computing section.