1. Field of the Invention
This invention relates to an apparatus for feeding flat products such as newspaper inserts, sheets or signatures into pockets or other areas of a machine, and more particularly to an improved feeder having accelerator and decelerator devices to improve feeding speed and efficiency.
2. Description of the Related Art
Typically, in a newspaper insert machine such as one shown in U.S. Pat. No. 4,723,770 or in U.S. Pat. No. 5,823,320, paper inserts or other flat products are placed in a stationary stack, and are fed by an automatic feeder one at a time from the bottom of the stack down into pockets moving beneath the feeder. Such feeders typically employ a rotating drum within the feeder to pull sheets from the bottom of the stack and feed them into the pockets.
There are several challenges that must be overcome in this arrangement to achieve very high speeds together with accurate and efficient paper handling. First, the product must be transferred as quickly as possible from a stationary stack to a moving pocket. When the product is being transferred vertically, the force of gravity is used to assist in product transfer. But gravity is not enough. Just letting the product fall into the pocket does not enable transfer speeds at the desired high rate. An additional mechanical pushing or pulling force is also needed. Next, the product, which in the case of thin, highly flexible paper inserts, must be transferred while keeping the product as straight as possible to maximize transfer speeds while minimizing crumpling or warping. Then, once the product has been transferred to the pocket or other area, it must not be allowed to “crash” into, crumple or jam inside the pocket, or to “bounce” out of the pocket after transfer.
Thus, there is a need for an accelerating device to grab and “shoot” the product down into the pocket or other parts of the machine as fast as possible. At the same time, there is also a need for a decelerating device adjacent to the accelerating device to slow down the product just before the product(s leading edge is about to reach the bottom of the pocket, to prevent the product from bouncing out of the pocket or crumpling within the pocket.