PURPOSE: To allow an operator riding a revolving body to easily check the running direction of a vehicle by sensing the amount of revolution of the revolving body in the upper part of the vehicle, and thereby displaying the revolving position of the revolving body in the running direction of the vehicle with respect to the direction fore and aft.

CONSTITUTION: A limit switch kick metal piece 6 is fixed to the advancing direction 5 side face of a revolving ring 4a on the vehicle side of a car 4. At a specified spacing obtained by dividing the whole circumference equally, a number of limit switches LS1-LS8 are arranged on a frame 7a of a revolving body 7 facing the ring 4a on vehicle side. Contact signals from limit switches LS1-LS8 are connected with lightup circuits for a number of lamps L1-L8 furnished also at equally divided circumference around the running display at a vehicle running control lever 8. When the revolving body 7 has revolved, for ex., 45 to the right, the switch LS8 is kicked by the metal piece 6 so as to light up the lamp L8. Thereby the running direction of the vehicle is displayed and operation of the lever 8 is facilitated.