Inking unit of a printing unit, printing unit and method for operating a printing unit

A printing unit of a printing machine for simultaneous multicolor printing, comprising:

• at least one transfer cylinder, a plurality of forme cylinders that cooperate with the at least one transfer cylinder, and an inking unit for each forme cylinder with which inking unit each said forme cylinder cooperates for its inking, the inking unit having at least one first inking unit roller, a second inking unit roller, and a third inking unit roller, which third inking unit roller is spaced at a distance from the first inking unit roller;
• a pivot drive to pivot the second inking unit roller between a first position in contact with the first inking unit roller and a second position in contact with the third inking unit roller, the pivot drive having a drive train including a drive means which is mechanically independent of a rotation of printing unit cylinders and of a rotation of additional inking unit rollers provided in the printing unit;
• an adjustment means to remotely set a contact force of the second inking unit roller relative to at least one of the first and the third inking unit rollers by one of predefining and modifying a setpoint value of a driving force of the drive means by operation of the adjustment means;
• wherein the drive means is one of a linear drive and a rotary drive which is actuated by applying a compressed fluid to the drive means, to pivot the second inking unit roller between both the first position in contact with the first inking unit roller and the second position in contact with the third inking unit roller by the application of the compressed fluid to the drive means and wherein the contact force of the second inking unit roller relative to the at least one of the first and the third inking unit rollers can be set by one of setting and varying a pressure level of the compressed fluid applied to the drive means;
• and
• wherein the pivot drive is prestressed by a torsion bar spring whereby, when the drive means is one of detached and switched to a resistance-free mode, a force which is counter to an acceleration of the second inking unit roller, which is induced by gravity, is introduced into the drive train of the pivot drive by the torsion bar spring.

A method for operating a printing unit having at least one first inking unit roller, and having a second inking unit roller which can pivot between a first position in contact with the first inking unit roller and a second position in contact with a third inking unit roller, which third inking unit roller is spaced at a distance from the first inking unit roller and, wherein the second inking unit roller is pivoted by a drive train including a drive means, including pivoting the second inking unit roller when it is acted upon by the drive means that is embodied as one of a compressed fluid actuated linear drive and a rotary drive, to pivot the second inking unit roller between both the first position in contact with the first inking unit roller and the second position in contact with the third inking unit roller by the application of the compressed fluid to the drive means and which drive means is remotely adjustable with respect to an output side driving force for one of setting and varying a contact force of the second inking roller relative to one of the first and third inking unit rollers by one of predefining and modifying a setpoint valve of the output side driving force of the drive means and prestressing the drive means using a torsion bar spring whereby, when the drive means is one of detached and switched to a resistance-free mode, using the torsion bar spring for introducing a force counter to an acceleration of the second inking unit roller, which is induced by gravity, into the drive train of the drive means.