b the guide surfaces 27 28 of the closing doctor blade 13 are cut out or recessed between the holding webs 25 26 so that the moved out guide surfaces 27 28 cannot become glued into the longitudinal slot 22 by the ink fig3 a and 3b show a chamber doctor 29 having an ink chamber 30 defined by a chamber doctor body 31 a working doctor blade 32 and a closing doctor blade 33 the working doctor blade 32 is fastened to a holder 34 which is swivelably supported at the chamber doctor body 31 by bearing pins 35 the closing doctor blade 33 is received in a holder 36 which is likewise swivelably supported at the chamber doctor body 31 by bearing pins 37 in this embodiment the working doctor blade 32 and the closing doctor blade 33 are pressed against and readjusted toward the inked cylinder 2 by work cylinders 38 39 for this purpose the work cylinders 38 39 act at the holders 34 36 and rest against the chamber doctor body 31 in this instance a side surface of the working doctor blade 32 serves as a sealing surface 40 which forms a gap seal together with a sealing edge 41 of the chamber doctor body 31 in order to seal the holder 36 relative to the chamber doctor body 31 a seal 42 which works together with a sealing surface 43 of the holder 36 is recessed into the chamber doctor body 31 the sealing surface 43 advantageously has a curvature with the radius around the swivel point of the holder 36 bearing pin 37 in this embodiment the chamber doctor 29 need not be moved away from the inked cylinder in order.