Bag tying apparatus

Bag tying apparatus for tying up a gathered neck of a bag with a tie, comprising:

• a tie wrapping plate moveable linearly over a predetermined stroke and having a stepped groove extending in the moving direction of the wrapping plate, the stepped groove having a narrow section for receiving a gathered neck of a bag, and an elongated recess running across the stepped groove, the elongated recess having a bottom on which to receive a tie material;
• a pleating mechanism disposed above and behind said wrapping plate in the moving direction thereof and for clamping the open end of the bag into pleats and for then gathering the pleated open end of the bag into a gathered neck,
• a cutter disposed on one side of said wrapping plate and being movable together with said wrapping plate so as to cut a tie of a predetermined length from said tie material on said bottom of said elongated recess during the initial stage of the moving stroke of said wrapping plate, said tie being bent into a U-shape as the gathered neck of the bag comes into said narrow section of the stepped groove during the final stage of the moving stroke of said wrapping plate;
• and
• a tie twisting mechanism arranged above said wrapping plate, said tie twisting mechanism including a twist shaft which is rotatable but immovable in the axial direction thereof, said twist shaft having upper and lower end portions, a pair of twist hooks secured to a lower end portion of the twist shaft and engageable with the ends of the U-shaped tie, and a toothed disc secured to the upper end portion of the twist shaft, the twist hooks being adapted to twist the ends of the U-shaped tie when the toothed disc is rotated, to thereby tie up the gathered neck of the bag.