| 摘要 |
<p>A strand advanceable from a supply spool to a weaving machine of the shuttleless type under variable tension is routed through an adjustable braking mechanism. The braking mechanism includes a flat guide plate along which the strand advances, the strand being contacted at longitudinally spaced portions of the guide plate by means of a succession of angularly depending leaf springs which are carried at longitudinal intervals in an overlying holding member. The input end of the holding member is pivotally supported on a frame member that carries the guide plate, and a helical spring biases the holding member obliquely relative to the underlying guide plate so that the distance between the holding member and the guide plate increases in the direction of advance of the strand. The angle formed by the depending leaf springs from the lower surface of the holding member successively increases, and the length of the depending arms are so chosen that the lower ends of the arms come into substantial registration on the upper surface of the guide plate through the intervening strand. A screw and lock nut mechanism is provided for selectively moving the holding member downwardly toward the guide plate against the force of the helical spring to vary the contact pressure of the resilient arms on the strand and also to increase the differential in contact pressure applied by the successive resilient arms.</p> |
