| 摘要 |
PURPOSE: To eliminate danger of damaging a drive train by predicting generation of an overspeed condition as a function of speed signals, and adjusting the displacement of a hydraulic motor in accordance with prediction of the overspeed condition. CONSTITUTION: The control means 116 of an overspeed control device 102 reads a mode switch 118, and adjusts the displacement of a hydraulic motor 108 accordingly. When the mode switch 118 is at a low speed position, the control means 116 actuates in a low speed mode, and sets the displacement of the hydraulic motor 108 at the maximum. When the mode switch 118 is at a high speed position, the control means 116 actuates in a high speed mode, and adjusts the displacement of the hydraulic motor 108 both for the low speed and the high speed of the hydraulic motor 108. When a motor speed is increased to a specified value, an overspeed condition is detected. As the overspeed condition is detected, the control means 116 adjusts the motor displacement from the minimum to a specified ratio of the maximum. |
