Stacker device for flat articles stacked on edge, and a postal sorting machine

A stacker device for flat articles stacked on edge, said stacker device comprising at least one support defining a bearing plane suitable for receiving said stack of flat articles being formed along a predefined stacking path, a retaining paddle carried by a first slideway disposed laterally relative to said bearing plane and along which said retaining paddle is mounted to be moveable in translation along said stacking path between an upstream position and a downstream position, and to be retractable manually between a working position in which it extends above said bearing plane to a first working height and interferes with said stacking path so as to receive the surface of a flat article bearing against it and a resting position in which it does not interfere with said stacking path, said retaining paddle being coupled to braking means arranged to oppose movement of said retaining paddle during stacking, said stacker device being characterized in that it includes at least one holding finger suitable for being in a deployed position in which it extends above said bearing plane to a second working height less than said first working height and interferes with said stacking path so as to receive the foot of a flat article bearing against it, said holding finger being carried by a second slideway distinct from said first slideway, disposed laterally relative to said bearing plane on the same side as said first slideway and along which said bearing finger is mounted to be moveable in translation along said stacking path between a rear position and a front position, said holding finger being coupled to return means tending to oppose movement of said holding finger so as to prevent the foot of said flat article from slipping towards the front of said stack, said holding finger and said retaining paddle being arranged to be independent from each other so that said holding finger is suitable for retaining said foot of the flat article even when said retaining paddle is in its resting position, said holding finger in a deployed position being further arranged to be displaced by said retaining paddle in a working position when the latter is moved to its downstream position so that said retaining paddle and said holding finger advance gradually and simultaneously as the stack of said stack of flat articles is being formed behind said retaining paddle.