Pregripper in a sheet-fed printing machine

A pregripper configuration for single-sheet feeding to a rotating cylinder in a sheet-fed rotary printing press, comprising:

• a pregripper pivot arm pivotally mounted at a printing press frame;
• a cam drive, including a cam, a roller lever pivotable about a pivot shaft being fixed relative to the printing press frame, and lever means articulatingly connected between said roller lever and said pregripper pivot arm for transmitting a motion of said roller lever to said pregripper pivot arm;
• a rigid link having a first end articulated at said roller lever and a second end articulated at said pivot arm;
• said roller lever having a roller lever attachment point and said pivot arm having a pivot arm attachment point;
• and
• an initially tensioned spring disposed between said roller lever attachment point and said pivot arm attachment point, said spring extending approximately parallel to said rigid link.