| 摘要 |
<p>500,079. Sewiag-machines. SIGODA, V. J. Jan. 21, 1938, No. 2102. [Class 112] [Also in Group VIII] A pinking-device for a sewing-machine comprises a cutting member rotatable in the plane of the fabric at one side of the stitchforming devices. In the form shown, a ring 26, with cutting teeth 27 on its top face, is mounted on roller bearings eccentrically in a carrier 17 which is rotatably adjustable on the base-plate of the machine at one side of the throat-plate 12. Inside the ring is a disc 21 rotatably mounted in the carrier 17 and oscillated by an arm 34 connected to the feed-operating mechanism of the machine ; the disc 21 carries friction pawls 38 which engage a ridge 35 on the cutting ring 26 to rotate the latter intermittently in one direction, backward movement of the ring 26 being prevented by a similar pawl 40 carried by a part 41 integral with the carrier 17. The distance of the cut edge of the fabric from the line of stitching is varied by rotating the carrier 17 by means of a hand-operated pinion 44 engaging teeth on the periphery of the carrier ; the carrier may be held in an adjusted position by a clamping nut 45. The fabric is pressed on the cutting teeth by a roller 48 carried on an arm 49 which is pivotally mounted in a base 51 and pressed down by means of a screw 52 carried by an arm fixed to the pivot pin; the base 51 is adjustable on the base-plate of the machine in accordance with the position of the cutting ring. In a modification the cutting ring is replaced by a disc carried by a spindle rotatable in the carrier 17, and the spindle has a one-way clutch connection with the arm 34 and a reverse-movement-preventing connection with a fixed part. An undulating edge may be produced on the fabric by rotating the pinion 44 continually by connecting it to the feed mechanism in a similar manner to the cutting disc ; the pinion 44 is then carried by an arm which can be moved to bring it into or out of engagement with the carrier at will, a locking tooth on the arm engaging the carrier when the pinion is disengaged from it to produce a straight edge. The fabric may be fed to the stitching and cutting devices through a folding- device adjustably mounted on the base-plate.</p> |
