| 摘要 |
<p>A double arm type hydraulic excavator(200) has two work fronts (A, B) composed respectively of arms (12a, 12b), of booms (10a, 10b), and of working tools (20a, 20b) and vertically pivotably mounted on both left and right sides of the front part of an upper rotation body (3). If ?c is an arm average angle that is the average of the angles ?a, ?b of the arms (12a, 12b) relative to the booms (10a, 10b) of the two work fronts (A, B), N is an unstable region in which the arm average angle ?c is greater than a predetermined threshold value ?c2, and M is a stability limit region that is a region set adjacent to the inner side of the unstable region, and if the arm average angle ?c is in the stability limit region M, then a drive signal is decreased to reduce the operating speeds of the arms (12a, 12b). By this, even if outputs of the two work fronts (A,B) are increased, degradation in the stability of the machine is minimized.</p> |
