Method for controlling driving speed of construction machinery

Abstract

Disclosed is a method for controlling a driving speed of construction machinery for preventing a sudden change in the driving speed during a combined operation for operating a work device while driving an excavator. The method for controlling the driving speed of the construction machinery, according to one embodiment of the present invention, relates to the method for controlling the driving speed of the construction machinery comprising a lower driving body, a turning device for turning an upper turning body with respect to the lower driving body, a driving device, the work device, an electronic proportional valve for controlling the discharge flow rate of a hydraulic pump, and a controller. The method comprises: a first step of detecting the amount of operation of the driving device, the work device, and the turning device according to the operation of same; a second step of calculating a required working oil flow rate corresponding to the amount of operation of the driving device, the work device, and the turning device; a third step of reducing the required working oil flow rate of the driving device calculated in the second step, according to a ratio set by a driver, so that an independent maximum driving speed of the driving device can be reduced by the setting by the driver; and a fourth step of combining the required working oil flow rates calculated in the second step and the third step, and outputting a control signal to the electronic proportional valve so that the combined flow rate is discharged from the hydraulic pump.

1 . A traveling speed control method for a construction machine including a lower traveling structure, a swing apparatus configured to swing an upper swing structure with respect to the lower traveling structure, a traveling apparatus, a working apparatus, an electronic proportional valve configured to control a discharge flow rate of hydraulic fluid discharged from a hydraulic pump, and a controller, the traveling speed control method comprising:
 a first step of detecting the manipulation amounts of the traveling apparatus, the working apparatus, and the swing apparatus according to the manipulation of the traveling apparatus, the working apparatus, and the swing apparatus;   a second step of calculating required flow rates of hydraulic fluid, which correspond to the manipulation amounts of the traveling apparatus, the working apparatus, and the swing apparatus;   a third step of decreasing the required flow rate of hydraulic fluid of the traveling apparatus, which is calculated in the second step in accordance with a ratio set by an operator so that a separate maximum traveling speed of the traveling apparatus can be decreased by an operator's setting; and   a fourth step of outputting a control signal to the electronic proportional valve so that the required flow rates of hydraulic fluid, which are calculated in the second and third steps, are combined and the combined flow rates of the hydraulic fluid is discharged from the hydraulic pump.   
     
     
         2 . The traveling speed control method according to  claim 1 , wherein a determination means determines whether the traveling apparatus, the working apparatus, and the swing apparatus are manipulated based on an electrical signal value that is output by the manipulation of an electric joystick or a secondary pressure value that is output by the manipulation of a hydraulic joystick. 
     
     
         3 . The traveling speed control method according to  claim 1 , wherein any one of an on/off function switch, a potentiometer, a display device, and a cluster, which are installed in a cabin of the machine is used as a setting means capable of reducing the separate maximum traveling speed of the traveling apparatus by the operator's setting.