Patent attributes
An embodiment of the present invention relates to construction machinery comprising: a first hydraulic pressure line which is connected to a main control valve and one side of a swing motor; a first valve arranged on the first hydraulic pressure line; a first pressure detection member which detects the pressure of the hydraulic oil passing through the first hydraulic pressure line between the first valve and the main control valve; a fourth pressure detection member which detects the pressure of the hydraulic oil passing through the first hydraulic pressure line between the swing motor and the first valve; and a control unit which calculates the flow rate of the hydraulic oil discharged from the swing motor on the basis of the pressure of the hydraulic oil detected by the first pressure detection member and the pressure of the hydraulic oil detected by the fourth pressure detection member.
