PURPOSE: To clear the oil supply state of one of oil supply nozzles and to pre vent the pretending supply of oil, by respectively connecting the oil supply nozzles to two hoses connected to one flowmeter to provide two display meters and further providing a control apparatus for stopping the display output of the display meter of one oil supply nozzle during the use of the other oil supply nozzle.

CONSTITUTION: Oil supply nozzles N1, N3 are connected to a flowmeter 13 through hoses M1, H3 and a control apparatus 2 outputs an operation signal to a motor MO13 on the basis of the signals from nozzle switches NSW 1, NSW 2 and a flow rate pulse oscillator R13 and allows display meters I1, I3 to respectively light to output display signals displaying the oil supply amounts of oil supply nozzles N1, N3. Further, during the use of the oil supply nozzle N1 or N3, the display output to the display meter I3 or I1 corresponding to the other oil supply nozzle N3 or N1 is stopped. Therefore, for example, during the use of the oil supply nozzle N1, that is, at the time when the nozzle switch NSW 1 is turned ON, the display output to the display meter I3 is stopped and, therefore, it can be cleared that the oil supply nozzle N1 is used and the pretending supply of oil by the nozzle N3 can be prevented.