US 4,907,392 A · Machine for applying twist-type ties

Abstract

A machine for applying a twist-type tie to the neck of a bag has a path and sets of endless belts which come together at a nip along the path to propel a bag neck which passes into the nip forwardly to a typing zone in the path. Here a twist-type ribbon crosses the path and is secured at its end in a holder. An endless chain carries a pusher tab up to the tying zone behind the bag neck, causing the bag neck to gather behind and deflect the ribbon, then pauses, and thereafter resumes its forward motion to drive the bag neck out of the machine. During the pause a bag clamp secures the bag neck against a surface that is along the path and a needle lifts a portion of the ribbon upwardly behind the gathered bag neck and brings that portion of the ribbon to the holder so that the ribbon loops below the bag neck in the form of leading and trailing segments. While the needle is so extended, a twister hook gathers its leading and trailing segments and twists them together. As the tie is completed, the holder shears the trailing segment of ribbon and at the same time grips that segment so the ribbon remains extended across the path. A ribbon stripper moves forwardly from behind the twister hook and clears the severed twist tie from the tying zone as the pusher tab resumes its forward motion.

Claims22

Dependent claims

In a machine for applying a twist-type tie to a bag neck and including ribbon placement means for looping a twist-type ribbon around a gathered bag neck so that the ribbon has two segments which project away from the neck, and twister means for twisting the two segments together, an improved device for holding one segment of the ribbon as the ribbon placement means loops the ribbon around the neck and for severing the other segment as the tie is completed, said device comprising:

spaced apart jaws;
a clamping element movable generally between the jaws to clamp the ribbon alternately between one side of the element and one jaw and the other side of the element and the other jaw;
drive means for moving the clamping element between the jaws;
and a shear plate located below the jaws and having cutting edges positioned along the jaws such that the clamping element will move the ribbon across a cutting edge as it clamps the ribbon against a jaw so as to sever the ribbon, the shear plate during operation of the clamping element being in a fixed position with respect to the jaws, yet being spaced from the jaws so that a gap exists between the shear plate and the jaws in the region of the cutting edges on the shear plate.

1 more element

In a machine for deriving from a ribbon, which extends through a path, a twist-type tie for securing the end of a bag neck in a gathered condition, the machine including a bag drive for directing the neck against the ribbon where it extends through the path, a needle for elevating a portion of the ribbon behind the gathered bag neck so that the ribbon has leading and trailing segments and twist means for twisting the leading and trailing segments together, a holder and shear unit for securing the ribbon at the end of its leading segment and for severing the trailing segment to free the twist tie which is formed from the leading and trailing segments, said holder and shear unit comprising:

a clamping block mounted over the path and having a clamping slot at which the leading segment of the ribbon is secured and into which the needle places the trailing segment, the block having jaws which are present toward each other across the slot;
a clamping element movable through the slot from one jaw to the other for clamping the end of the ribbon against one of the jaws, the clamping element at the slot being narrower than the slot so that the needle can place the trailing segment of the ribbon between the clamping element and one of the jaws;
a fluid operated cylinder connected to the clamping element for moving the element through the slot from one jaw to the other jaw and back again;
and a shear plate located below the block and having a cutout aligned with the slot of the block and also having first and second cutting edges which are presented toward each other across the cutout, the first cutting edge being located along the first jaw and the second cutting edge along the second jaw, with the first cutting edge being offset slightly with respect to the first jaw and the second cutting edge being offset slightly with respect to the second jaw, such that the clamping element will force the ribbon into the first cutting edge and sever it as the element moves toward the first jaw and will force the ribbon into the second cutting edge and sever it as the element moves toward the second jaw.

1 more element

Dependencies are inferred from the claim text.

Machine for applying twist-type ties

Life of this patent

Machine for applying twist-type ties

Life of this patent

Abstract

Claims22