Abstract: A system capable of appropriately cooling a generator and a power cable connected to the generator, disposed in a hot section of a turbo-fan engine, regardless of a rating of the engine is provided. The system includes: a junction box; a bypass air duct that supplies, to the junction box, air extracted from a portion of a bypass flow path of the engine on a side further downstream than a fan outlet; a core air duct that supplies, to the junction box, air extracted from a portion of a core flow path of the engine on a side further upstream than a compressor outlet; and a cooling air duct that extends from the junction box to a space for accommodating the generator, and valves capable of being independently controlled to open and close are provided at downstream ends of the bypass air duct and the core air duct.

Abstract: A system capable of appropriately cooling a generator and a power cable connected to the generator, disposed in a hot section of a turbo-fan engine, regardless of a rating of the engine is provided. The system includes: a junction box; a bypass air duct that supplies, to the junction box, air extracted from a portion of a bypass flow path of the engine on a side further downstream than a fan outlet; a core air duct that supplies, to the junction box, air extracted from a portion of a core flow path of the engine on a side further upstream than a compressor outlet; and a cooling air duct that extends from the junction box to a space for accommodating the generator, and valves capable of being independently controlled to open and close are provided at downstream ends of the bypass air duct and the core air duct.

Abstract: A work vehicle includes a drive source, a travel device, a hydraulic pump, a work implement, a traction force detector, a lift force detector and a controller. The traction force detector is configured to detect traction force of the work vehicle. The lift force detector is configured to detect lift force for raising the work implement. The controller is configured to compare a predetermined threshold and a ratio between the lift force and the traction force, and to execute traction force reduction control for reducing the traction force when an increase in the lift force is required.

Abstract: A work vehicle includes a controller. The controller is configured to determine whether low-load conditions indicating that the work vehicle is in a low-load state are satisfied. The controller is configured to control an engine so that an upper limit value of an output torque of the engine when the low-load conditions are satisfied is made less than when the low-load conditions are not satisfied. Also, the controller is configured to vary a reduction amount of the upper limit value of the output torque of the engine when the low-load conditions are satisfied, in accordance with variation in at least one of vehicle speed, vehicle acceleration, and engine-rotation-speed acceleration, and in accordance with variation in engine rotation speed.

Abstract: A work vehicle includes a controller. The controller is configured to determine whether low-load conditions indicating that the work vehicle is in a low-load state are satisfied. The controller is configured to control an engine so that an upper limit value of an output torque of the engine when the low-load conditions are satisfied is made less than when the low-load conditions are not satisfied. Also, the controller is configured to vary a reduction amount of the upper limit value of the output torque of the engine when the low-load conditions are satisfied, in accordance with variation in at least one of vehicle speed, vehicle acceleration, and engine-rotation-speed acceleration, and in accordance with variation in engine rotation speed.

Abstract: A work vehicle includes a drive source, a travel device, a hydraulic pump, a work implement, a traction force detector, a lift force detector and a controller. The traction force detector is configured to detect traction force of the work vehicle. The lift force detector is configured to detect lift force for raising the work implement. The controller is configured to compare a predetermined threshold and a ratio between the lift force and the traction force, and to execute traction force reduction control for reducing the traction force when an increase in the lift force is required.

Abstract: In an engine load control device of a work vehicle, an output of an engine is transmitted to a hydraulic actuator via a variable displacement type hydraulic pump. A controller is configured to calculate, based on a target rotational speed of the engine detected by a target rotational speed detecting portion and an actual rotational speed of the engine detected by an actual rotational speed detecting portion, a variation rate per unit time of a difference between the detected results, and to adjust the maximum absorbing torque of the hydraulic pump according to the magnitude of the variation rate.

Abstract: A fluid tank includes a tank main body that contains a fluid and a bubble removing device that is provided inside the main body and removes bubbles in the fluid. The main body includes a partition and a delivery port through which the fluid is fed to outside. The bubble removing device has an outflow port through which the fluid from which the bubbles have been removed flows to the inside of the main body and a bubble exhaust port through which the bubbles which have been removed are discharged to the inside of the main body. The delivery port is provided adjacent to the outflow port relative to the partition. The partition partitions the inside of the main body into a side in which the outflow port and the delivery port are provided and a side of the bubble exhaust port.

Abstract: In an engine load control device of a work vehicle, an output of an engine is transmitted to a hydraulic actuator via a variable displacement type hydraulic pump. A controller is configured to calculate, based on a target rotational speed of the engine detected by a target rotational speed detecting portion and an actual rotational speed of the engine detected by an actual rotational speed detecting portion, a variation rate per unit time of a difference between the detected results, and to adjust the maximum absorbing torque of the hydraulic pump according to the magnitude of the variation rate.

Abstract: A fluid tank includes a tank main body that contains a fluid and a bubble removing device that is provided to an inside of the tank main body and removes bubbles contained in the fluid. The tank main body includes a partition that partitions the inside of the tank main body to at least two sides and a delivery port through which the fluid is fed to an outside. The bubble removing device has an outflow port through which the fluid from which the bubbles have been removed flows to the inside of the tank main body and a bubble exhaust port through which the bubbles which have been removed are discharged to the inside of the tank main body. The delivery port is provided adjacent to the outflow port relative to the partition. The partition partitions the inside of the tank main body to a side in which the outflow port and the delivery port are provided and a side of the bubble exhaust port.

Abstract: A hydraulic excavator is equipped with one or more downsizing scheme including at least one of: (i) a bubble removing device for removing bubbles in hydraulic fluid, (ii) a hydraulic tank including a main tank and a variable capacity tank arranged separately from each other, and (iii) a variable capacity tank or hydraulic tank which is fitted to the rear surface of the upper cover of the seat-side block. Thus, the lateral section of the seat can be ultimately downsized to provide a large space around the seat. Then, unlike the prior art, a canopy or a cab of a larger hydraulic excavator can be securely arranged on the upper swing body of a small hydraulic excavator. Since such large parts can be commonly used with large hydraulic excavators, it is possible to significantly reduce the cost of the hydraulic excavator.

Abstract: A hydraulic excavator is equipped with one or more downsizing scheme including at least one of: (i) a bubble removing device for removing bubbles in hydraulic fluid, (ii) a hydraulic tank including a main tank and a variable capacity tank arranged separately from each other, and (iii) a variable capacity tank or hydraulic tank which is fitted to the rear surface of the upper cover of the seat-side block. Thus, the lateral section of the seat can be ultimately downsized to provide a large space around the seat. Then, unlike the prior art, a canopy or a cab of a larger hydraulic excavator can be securely arranged on the upper swing body of a small hydraulic excavator. Since such large parts can be commonly used with large hydraulic excavators, it is possible to significantly reduce the cost of the hydraulic excavator.

Abstract: A fluid tank fluid is provided which includes a bubble removing device provided therein to remove bubbles from the fluid. The bubble removing device includes a cyclone chamber for generating a swirling current in the fluid flowing therethrough to separate bubbles from the fluid. At least one outflow port is provided through which the fluid from which the bubbles have been separated flows from the cyclone chamber. And an exhaust port is provided through which the bubbles separated from the fluid are driven from the cyclone chamber.

Abstract: A hydraulic excavator is equipped with one or more downsizing scheme including at least one of: (i) a bubble removing device for removing bubbles in hydraulic fluid, (ii) a hydraulic tank including a main tank and a variable capacity tank arranged separately from each other, and (iii) a variable capacity tank or hydraulic tank which is fitted to the rear surface of the upper cover of the seat-side block. Thus, the lateral section of the seat can be ultimately downsized to provide a large space around the seat. Then, unlike the prior art, a canopy or a cab of a larger hydraulic excavator can be securely arranged on the upper swing body of a small hydraulic excavator. Since such large parts can be commonly used with large hydraulic excavators, it is possible to significantly reduce the cost of the hydraulic excavator.

Abstract: A hydraulic excavator is equipped with one or more than one downsizing scheme of arranging a bubble removing device for removing bubbles in hydraulic fluid, using a hydraulic tank including a main tank (51) and a variable capacity tank (52) arranged separately from each other and/or fitting the variable capacity tank (52) to the rear surface of the upper cover. Thus, the lateral section of the seat can be ultimately downsized to provide a large space around the seat. Then, unlike the prior art, a canopy or a cab of a large hydraulic excavator can be securely arranged on the upper swing body of a small hydraulic excavator. Since such large parts can be commonly used with large service vehicles, it is possible to significantly reduce the cost of the service vehicle.

Abstract: A cyclone type bubble removing device 30 is arranged in a hydraulic tank 1. Therefore, it is no longer necessary to secure a space for installing a bubble removing device 30 outside the tank 1 and hence the space dedicated to the hydraulic system can be reduced. Since the bubble removing device 30 is fitted to the inside of the hydraulic tank 1 in advance, it does not need to be installed separately somewhere in the hydraulic circuit so that the installing operation can be performed quickly. Additionally, the outflow ports 322 for causing hydraulic fluid from which bubbles have been removed to flow out and the exhaust port 333 for expelling bubbles are arranged separately so that it is possible to expose the exhaust port 333 to the drain space 127. Thus, if the hydraulic tank 1 is rocked to a large extent, the hydraulic fluid coming out of the outflow ports is not mixed with bubbles and hence bubbles can be eliminated reliably.