| 摘要 |
<P>PROBLEM TO BE SOLVED: To securely prevent an engine from being stopped when an abrupt high hydraulic pressure load is applied thereto. <P>SOLUTION: When an operator abruptly operates a loader operation lever upward while operating a steering wheel, the hydraulic pressure loads of a steering hydraulic pump 7 and a loader hydraulic pump 8 are abruptly increased. Accordingly, the hydraulic pressure loads move to a line for high hydraulic pressure load shown by Tp1. The engine 1 tries to increase a torque to match with the high hydraulic pressure load Tp1 (point V1 on regulation line FL), as shown by C1, the rise of the torque of the engine does not follow up the abrupt rise of the hydraulic pressure load (time delay occurs), and the actual rotational speed Nr of the engine 1 becomes equal to or less than a threshold Nc, a controller 18 performs a control to lower the absorbing torques of variable displacement hydraulic pumps 7, 8, and 9 when it determines that the engine rotational speed Nr detected by an engine rotational speed detection sensor 1a lowers to a threshold Nc or below. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
