A new flats-delivering device has been invented to improve the straight and parallel alevel of fibers in a friction spinning fram. The principle of the friction spinning based on the flats-delivering device called tapered pipe and open-space flats has been investigated. New concepts of the “curvilinear-transmitting” and the “parallel condensing” have been suggested to explain the theory of the new divice. The transmission experiments of this improved device has also been reported. It was found that this new device could achieve the effect of straighten and paralleled fibers when fibers sucked into the v-zone of the dust drums in a friction spinning fram.