Axially shiftable sheet gripper assembly

An axially shiftable sheet gripper assembly for a sheet transfer drum of a sheet fed rotary printing machine, said sheet gripper assembly comprising:

• a plurality of sheet gripper fingers carried on a controllable sheet gripper shaft and engageable with a sheet gripper abutment surface;
• an axially shiftable sheet gripper carriage on which said sheet gripper shaft and said sheet gripper abutment surface are arranged, said axially shiftable sheet gripper carriage being shiftable axially in a groove in said sheet transfer drum, said groove extending generally parallel to an axis of rotation of said sheet transfer drum;
• and
• means for effecting said axial shifting of said carriage in said groove, said means including a control disk having a portion secured to a fixed pivot axis which lies on a side face of said control disk facing a side surface of said sheet transfer drum and having a free portion which is pivotable about said fixed pivot axis toward and away from said side surface of said sheet transfer drum, said means further including a control roller carried on said axially shiftable sheet gripper carriage, said control roller being in rolling contact with said side face of said control disk whereby pivoting of said control disk about said fixed pivot axis moves said side face of said control disk toward and away from said side surface of said sheet transfer drum to effect said axial shifting of said sheet gripper carriage in said groove.