Abstract: In a hydraulic excavator, in a rear part of an upper rotating body mounted on a lower traveling body is disposed an engine room, and in a front surface of a partition wall for partitioning the front surface side of the engine room from the exterior is provided a step serving as a foothold for opening and closing a bonnet and performing maintenance work. On the lower side of the step, a duct for exhausting the air within the engine room to the exterior is formed in a state that the step serves as an upper surface wall of the duct.

Abstract: On the premise that a partition wall for defining an engine room is provided on the left side of a rear portion of an upper frame the partition wall constituting an upper rotating body and that an engine and a cooler are disposed in the engine room, a front support frame which supports a front portion of the cooler is connected to a rear surface of the partition wall in a state of surface abutment against the rear surface, whereby the support frame also serves as a support pillar for the partition wall, the partition wall also serves as a stay for the prevention of transverse vibration of the support frame, and the use of a sealing member for filling up a gap between the partition wall and the support frame can be omitted.

Abstract: To improve soundproof performance on an air intake side of a cooling structure of a construction machine without enlarging an air intake chamber. An air intake chamber is provided on the air intake side of a heat exchanger in an engine room, and a first air intake port is formed in a top face of the air intake chamber. In the air intake chamber, a duct independently formed as a shield member is disposed so as to partition the air intake chamber into two chambers, and also such that the core surface of the heat exchanger is enclosed airtightly from the surrounding atmosphere. A second air intake port is formed in the duct; thereby, the air intake chamber is constituted in a doubled duct structure, and air sucked from the first air intake port is guided through an air intake passage to the core surface of the heat exchanger, the air intake passage being bent so as to be roughly L-shaped.

Abstract: On the front surface side of a cooler, a filter mounting portion provided with a filter abutment surface with which a filter is brought into abutment from the front side of the filter mounting portion is provided. The front end side of the filter pushed in from a maintenance port is pressed onto an elastic body formed of a plate spring and provided in the filter mounting portion. Thereby, by a pressing force F1 serving as a component force of a restoring force F of the elastic body, the filter is pressed onto the filter abutment surface, and by a position fixing force F2, the filter is pushed rearwards so as to ensure an engagement state of an engaging claw and an engaging hole.

Abstract: Problem: To improve a soundproof performance on an air intake side of a cooling structure of a construction machine without enlarging an air intake chamber. Solution: An air intake chamber (16) is provided on the air intake side of a heat exchanger (15) in an engine room (12), and a first air intake port (17) is formed in a top face of the air intake chamber (16). In the air intake chamber (16), a duct (18) independently formed as a shield member is disposed so as to partition the air intake chamber (16) into two chambers (16a), (16b), and also in a manner such that the core surface (15a) of the heat exchanger (15) is enclosed airtightly from the surrounding atmosphere.

Abstract: On the front surface side of a cooler, a filter mounting portion provided with a filter abutment surface with which a filter is brought into abutment from the front side of the filter mounting portion is provided. The front end side of the filter pushed in from a maintenance port is pressed onto an elastic body formed of a plate spring and provided in the filter mounting portion. Thereby, by a pressing force F1 serving as a component force of a restoring force F of the elastic body, the filter is pressed onto the filter abutment surface, and by a position fixing force F2, the filter is pushed rearwards so as to ensure an engagement state of an engaging claw and an engaging hole.

Abstract: An engine, a cooling fan and a heat exchanger are disposed within an engine room covered with a cover member, while an intake chamber is formed on an intake side of the heat exchanger. A first intake port is formed in an upper chamber wall of the intake chamber and a duct is disposed on a front face side of a heat exchanger core surface in the intake chamber. In a cooling structure of a construction machine which premises the above construction, a front face portion of the duct is inclined in a direction in which the sectional area of an intake passage formed between the duct front face portion and a side face portion of the cover member becomes maximum at the upper portion and decreases gradually toward the lower portion, and a second intake port is formed in a lower half of the front face portion.

Abstract: In a hydraulic excavator, in a rear part of an upper rotating body mounted on a lower traveling body is disposed an engine room, and in a front surface of a partition wall for partitioning the front surface side of the engine room from the exterior is provided a step serving as a foothold for opening and closing a bonnet and performing maintenance work. On the lower side of the step, a duct for exhausting the air within the engine room to the exterior is formed in a state that the step serves as an upper surface wall of the duct.

Abstract: On the premise that a partition wall for defining an engine room is provided on the left side of a rear portion of an upper frame the partition wall constituting an upper rotating body and that an engine and a cooler are disposed in the engine room, a front support frame which supports a front portion of the cooler is connected to a rear surface of the partition wall in a state of surface abutment against the rear surface, whereby the support frame also serves as a support pillar for the partition wall, the partition wall also serves as a stay for the prevention of transverse vibration of the support frame, and the use of a sealing member for filling up a gap between the partition wall and the support frame can be omitted.