| 摘要 |
A dump truck includes: an oil-cooling center brake; a first hydraulic pump supplying cooling oil to the center brake a second hydraulic pump supplying cooling oil to the center brake in addition to the cooling oil from the first hydraulic pump; a hydraulic motor driving the second hydraulic pump; a third hydraulic pump supplying hydraulic oil to the hydraulic motor; an open/close valve letting the hydraulic oil bypass the hydraulic motor; and a controller controlling a bypass flow amount at the open/close valve. A capacity of the first hydraulic pump corresponds to a flow amount of the cooling oil required to lubricate a transmission. A capacity of the second hydraulic pump corresponds to a flow amount for compensating the cooling oil from the first hydraulic pump when a brake is off. A capacity of the third hydraulic pump is smaller than the capacity of the second hydraulic pump. |
