Roving Frame

A roving frame, also called a speed frame or simplex machine, draws out a carded or combed sliver into roving, a thin, loosely twisted strand of fiber that is wound onto a bobbin and used as the direct feedstock for spinning yarn on a ring spinning frame or a mule. Inside the machine, sliver passes through a series of weighted drafting rollers that stretch it down to the fineness roving requires, after which a rotating flyer twists the strand just enough to hold it together without over-twisting it, before winding it evenly onto a bobbin that builds up in a cone shape as the machine runs. The roving frame emerged in the late eighteenth century as spinning mills mechanized, filling the gap between the carding engine, which produces a thick untwisted sliver, and the spinning frame, which needs a much finer, lightly twisted input, and the same three operations of drafting, twisting and winding that the roving frame performs in one pass remain the standard preparatory stage of ring spinning today.