Abstract: In a cooling structure for a construction machine, to appropriately install a condenser of an air conditioning system in a machine room to thereby ensure a superior cooling ability for a radiator and a oil cooler, while cooling the condenser, open air sucked by a fan through the intake ports cools a condenser, an oil cooler and a radiator successively, following which it is discharged to the outside through exhaust ports. The oil cooler is erected parallel to the radiator, while the condenser is inclined so as to extend from a portion near a lower end of the uppermost intake port formed in a side wall of an engine cover to a position near a lower end of the side-facing surface of the oil cooler.

Abstract: A cooling structure for a construction machine is disclosed to minimize the occurrence of a turbulent flow of air, provide a better cooling ability, and reduce surroundings noise. A recess is formed in a portion of an engine cover above a front portion of an engine, and exhaust ports are formed in a slope of the recess on the same side as a fan. A space having a proper size is thereby defined among a portion of the engine cover, which is positioned radially outside the fan, the exhaust ports and the fan. That portion of the engine cover constitutes a first guide for guiding the cooling air just after having passed the fan, as a laminar flow, to the exhaust ports, and an opposite slope of the recess constitutes a second guide for guiding the cooling air discharged through the exhaust ports as a laminar flow.

Abstract: A traveling control system for a hydraulically driven vehicle enables the vehicle to travel at a higher speed and also enables a vehicle body to be braked appropriately when the vehicle descends a slope with a travel control valve kept in its neutral position. The traveling control system includes pressure switches for detecting an operative state of a travel control valve, a detection line for detecting a shift position of a transmission, and a controller, a solenoid valve, load lines, a shuttle valve and a control line for cooperatively increasing the capacity of a travel motor upon the detection of that the travel control valve is in its neutral position and also the transmission is shifted to a high-speed gear. A timer function of the controller allows the capacity of the travel motor to be increased after the elapse of a predetermined time after the detection of that the travel control valve is in the neutral position.