Ink jet recording apparatus of the continuous jet type

An ink jet recording apparatus of the continuous jet type, comprising:

• nozzle means for receiving pressurized ink and forming the received pressurized ink into a uniform ink jet which disintegrates into a train of ink drops;
• recording signal generating means for generating a controlling voltage in response to s recording signal;
• charging means including a controlling electrode at which a recording signal from said recording signal generating means is received for selectively charging an ink drop;
• deflecting means for forming a deflecting electric field perpendicular to an ink jet flying axis to deflect a charged ink drop in a direction perpendicular to the ink jet flying axis;
• separating means for cutting a deflected ink drop but allowing s non-deflected ink drop to pass thereby;
• test signal generating means for generating a controlling signal which varies continuously;
• switch means for selectively coupling one of said recording signal generating means and said test signal generating means to said controlling electrode of said charging means;
• an electrically isolated conductive drop catcher for catching an ink drop which has passed by said separating means;
• current detecting means connected to said conductive drop catcher for detecting electric charge carried to said conductive drop catcher by charged ink drops as an electric current;
• and
• relative position detecting means for measuring a relative positional relationship between the ink jet flying axis and said separating means from a controlling voltage outputted from said test signal generating means and an output of said current detecting means.