Method and device for feeding printed products using alternating acceleration and deceleration phases

A device for feeding printed products from a stack to a collecting conveyor, the device comprising:

• a) a rotating drum having grippers for pulling a printed product from a the stack at a first location at a first preselected speed and releasing the printed product to the collecting conveyor at a second location at a second preselected speed;
• b) a variable-speed drive for driving the rotating drum having grippers so as to accelerate the rotating drum having grippers between the first and second locations while the gripper grips the printed product the rotating drum rotating at the second preselected speed greater than the first preselected speed;
• and
• c) a controller controlling the variable-speed drive and the collecting conveyor.

A method for transferring printed products comprising the steps of:

• pulling a printed product from a stack using a rotating drum having grippers, the rotating drum rotating at a first preselected speed;
• accelerating the rotating drum together with the grippers using a servo motor after pulling the printed product from the stack to a maximum speed while the gripper grips the printed product;
• releasing the printed product from the rotating drum having grippers to a collecting conveyor while the rotating drum having grippers is rotating at a second preselected speed greater than the first preselected speed;
• decelerating the rotating drum together with the grippers using the servo motor to the first preselected speed for pulling a next printed product from the stack;
• and
• controlling the servo motor and the collecting conveyor via a controller.

A method for transferring printed products between a stack and a collecting conveyor, comprising the steps of:

• pulling a printed product from the stack using a rotating drum having grippers, the rotating drum rotating at a first preselected speed;
• accelerating the rotating drum together with the grippers using a servo motor after pulling the printed product from the stack to a maximum speed while the gripper grips the printed product;
• releasing the printed product from the rotating drum having grippers to the collecting conveyor, while the rotating drum having grippers is rotating at a second preselected speed greater than the first preselected speed;
• decelerating the rotating drum together with the grippers using the servo motor to the first preselected speed for pulling a next printed product from the stack;
• operating the rotating drum having grippers at an average speed over acceleration and deceleration, between pulling the printed product from the stack and pulling the next printed product from the stack, such that release of each printed product is in a preselected synchronization to operation of the collecting conveyor;
• and
• controlling the servo motor and the collecting conveyor via a controller.