GB963498A - Apparatus for closing filled bags - Google Patents

Abstract

963,498. Sewing machines. RALSTON PURINA CO. Oct. 27,1961 [Dec. 13, 1960], No. 38503/61. Heading D1G. In a sewing machine for closing filled bags, the closed mouth of a bag on leaving the sewing position passes between a pair of rolls which are movable apart but which are biased together, the rolls being driven at a speed higher than the speed at which the work is fed past the stitching pring, whereby the thread chain trailing from the bag is held taut and can thereby be engaged with certainty by means adapted to move the thread into engagement with a thread cutter offset from the line of stitching. Filled bags B are passed in succession past the horizontal needle N of a sewing maching 3 which also comprises a feed dog 5 and presser plate 7. Positioned on the outlet side of the sewing machine is a pneumatic jack 11 the plunger 13 of which carries a fork 17 adapted, on actuation of the jack, to move the trailing thread chain C into engagement with a continuouslyoperated thread-cutter blade 9 offset from the line of stitching. The rigidity of paper bags holds the thread chain taut and in alignment with the fork 17, but in order that the chain-cutting device may operate with certainty on collapsible fabric bags, the filled mouth of each bag is passed between a pair of rolls 19, 21 which are driven at a speed about 50% higher than the feeding speed of dog 5. Roll 19 is carried by a shaft 23 journalled in a fixed sleeve 25 and driven via a universal coupling 61 and gears 59 form a shaft 63. Roll 21 is carried by a shaft 33 journalled in a sleeve 35 from which projects an arm 43 provided with a pintle 45 pivoted on a fixed bracket 51. A torsion spring acting on pintle 45 biases roll 21 into engagement with roll 19 and a gear pinion 39 on shaft 33 into member with a gear pinion 37 on shaft 23. Latch means, acting on arm 43, are provided for holding the rolls and pinions disengaged.