| 摘要 |
PURPOSE:To provide easy starting of an engine in a device, described in the heading, which has two hydraulic pumps by supplying one hydraulic pump connected to the engine with pressure oil from the other hydraulic pump which is driven by a readily started driving device. CONSTITUTION:The second hydraulic pump 9 supplies the first hydraulic pump 3 with pressure oil and a driving device 10 is a small-sized engine which drives the second hydraulic pump 9. In case an engine, when cool, is started, the driving device 10 is first turned and the second hydraulic pump 9 is driven to supply the pressure oil thereof for a pipe passage 3a of a closed circuit. Under the condition, a pilot control valve 16 is controlled to actuate a displacement variable mechanism driving device 4, making the displacement variable mechanism motored by the first hydraulic pump 3. The first hydraulic pump 3 is gradually started and an engine 1 is also started. If a stop valve 6 is closed, an oil pressure circuit toward the hydraulic motor 5 may be cut off, whereby producing no adverse influence on the hydraulic motor 5. |
