Control valve apparatus of power shovel

A control valve apparatus of a power shovel, comprising:

• a first hydraulic circuit system communicating with a first pump port connected to a first pump;
• a second hydraulic circuit system communicating with a second pump port connected to a second pump;
• a first working control valve provided in the first hydraulic circuit system to control a first working actuator;
• a second working control valve provided in the second hydraulic circuit system to control a second working actuator;
• and
• a second-working-actuator acceleration control valve provided in the first hydraulic circuit system and connected to the first working control valve in parallel,
• wherein the second-working-actuator acceleration control valve includes
• a pair of pilot chambers, one pilot chamber receiving a pilot pressure for switching the first working control valve, the other pilot chamber receiving a pilot pressure for switching the second working control valve, and
• a flow channel that guides a pressure fluid from the first pump port to an entrance port side of the second working control valve, and
• the second-working-actuator acceleration control valve is switchable between a first priority position in which a pressure fluid is guided to the first working control valve with a higher priority than the second working control valve by virtue of the pilot pressure of the one pilot chamber and a second priority position in which a pressure fluid is guided to the second working control valve with a higher priority than the first working control valve by virtue of the pilot pressure of the other pilot chamber.