摘要:
Disclosed are various needle-based devices for individualizing single fibers and other entities from a fibrous mass, particularly for testing purposes. In one embodiment, an accelerated pin drafting machine has a plurality of combing elements which sequentially pierce a fiber mat and move within a drafting zone with increasing distance between adjacent combing elements. The accelerated pin drafting machine in turn feeds a fiber individualizer. In another embodiment, a comb-like needle sampler is provided which moves past a perforated plate such that portions of fibrous material protruding through the perforations are loaded onto the needle sampler. An elastomer clamping feedroll moves against the needles to clamp the sample, and then rotates to gradually feed fibers from the sampler. As an alternative to the elastomer clamping feedroll, a clamping block presses against the needles, and the needles are slowly retracted to gradually release fibers. In a third embodiment, fibers protruding through a perforated plate are loaded onto a single needle, and the ends of the fibers are drawn into an airstream moving through a passage defined by a housing on either side of a fiber plate. The fiber plate subsequently engages the needle to clamp fibers in position and the housing retracts to expose the fiber plate for fiber preparation. Thereafter, a roll or apron feeds individual fibers from the fiber plate.