Folder having a retractable covering cam for changing operating mode

A folder for cutting and folding a web of paper comprising:

• a cutting device for cutting sheets from the web;
• a folding cylinder including movable retention devices and movable tucking blades for folding the sheets cut from the web, the cylinder being rotatably moved about an axis thereof;
• a first control cam for controlling the movement of the movable retention devices by contact with first cam followers;
• a second control cam for controlling the movement of the tucking blades by contact with second cam followers;
• at least one covering cam having a configuration for collect operation, the covering cam inhibiting at least one of the first and second control cams, and a configuration for straight operation where the covering cam does not inhibit the first and second control cams;
• and
• a switch for controlling the covering cam and a device for moving the switch between a radially remote position in which the switch guides an element carried by the covering cam radially outwards so the covering cam moves into the configuration for collect operation, and a close position in which the switch guides the element radially inwards so the covering cam moves into the configuration for straight operation;
• the covering cam including two semi-cams being substantially mutually symmetrical relative to the axis of the folding cylinder and radially movable between a retracted position and an extended position,
• the covering cam being in the configuration for straight operation when the semi-cams are in the retracted position and in a configuration for collect operation when the semi-cams are in the extended position.