GB1396338A - Thread trimming device for sewing machines - Google Patents

Abstract

1396338 Presser foot. Thread cutting SINGER CO 23 Aug 1972 39220/72 Heading D1G The needle thread 24 and underthread 28 are severed by first drawing the needle thread to one side of a hole 44 in a presser foot attachment 10, holding the thread in position, making another stitch and pulling the needle thread further away to draw the underthread through the hole and cutting both threads. The attachment 10 comprises a shank 12 and a presser foot sole 34 on which is slidably mounted a cutting blade 52 presenting an anvil 68 and urged to one side by a spring 70. The shank 12 rotatably mounts a shaft having at one end a knurled drum 130 and at the other a member 80 which supports a striker 84 and the thread drawing pin 82. The member 80 is urged anticlockwise by a spring (94, Fig 3, not shown) to a position where pin 82 is to the right of the needle. When severance is required the operator rotates the drum to move the pin across 'the hole beneath the raised needle to hold the needle thread during the subsequent stitch, a latch (144) within the drum 130 holding the drum in position against the action of the spring (94). Subsequent clockwise rotation of the drum by the operator pulls the bobbin thread through the hole and striker 84 abuts the anvil 68 to slide the blade 52 and sever the thread. The latch (144) is released by the drum motion and the device returned by its spring (94) to the position of Fig 1.