This application claims the priority of German Application No. 100 43 338.3 filed Sep. 2, 2000, which is incorporated herein by reference.
This invention relates to a fiber material feeder such as a weighing hopper feeder having a spiked lattice composed of an inclined endless belt which is supported by end rollers and which carries on its outer surface rows of spikes extending over the width of the carrier belt. The spiked lattice delivers fiber material to a weighing bin of a scale.
An exact metering of different fiber material components during fiber preparation is frequently performed by a weighing hopper feeder. As a rule, for each material component a separate weighing hopper feeder is provided. The transport of the material to the scale is preferably effected by a spiked lattice which has rows and columns of spikes which are oriented parallel to the axis of the end rollers of the spiked lattice. The circulating speed of the spiked lattice is varied as a function of the fiber mass in the weighing bin. The reason for such a speed variation is an exact metering at low circulating speeds just prior to reaching the desired weight in the weighing bin. Despite such a measure, the spiked lattice of conventional construction delivers the fiber material in batches to the combing station operating parallel with the spiked lattice. As a result, particularly at high outputs, weighing errors may occur since large, non-uniform fiber quantities may be carried by the spike rows.
It is an object of the invention to provide an improved fiber material feeder of the above-outlined type from which the discussed disadvantages are eliminated and which, in particular, makes possible a significant amelioration of the weighing accuracy with structurally simple means.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the fiber material feeder includes a spiked lattice which has an upper and a lower end roller each having a longitudinal axis. The spiked lattice has an inclined, endless belt supported on the end rollers and a plurality of spikes carried at the outer belt surface and forming a series of consecutive rows extending along the belt width oriented parallel to the roller axes. The spike rows are oriented at an oblique inclination to the roller axes. Further, a drive is provided for circulating the endless belt about the end rollers for advancing fiber material, entrained by the spikes, upwardly toward the upper end roller. A scale including a weighing bin is provided for catching fiber material leaving the belt at the upper end roller.
A sudden, batch-like discharge of the entire fiber material quantity from the spike rows is avoided by arranging the spike rows at an inclination to the rotary axis of the end rolls supporting the belt of the spiked lattice. Thus, the duration of discharge of the fiber material carried on any spike row is lengthened, resulting in a significantly more accurate metering of the fiber material with which the weighing bin is charged. In particular, the invention has the advantage at high output speeds that the operational steps occur more rapidly and the charging rate of the weighing bin is increased.