Bag, method, and machine for producing a foam-in-bag dunnage material
A bag for producing a foam-in-bag dunnage material comprises a closed edge portion and, in a non-sealed state of the bag, an open edge portion, the closed and open edge portions delimiting an inner bag volume. The invention proposes that a bag structure of the bag comprises a mixing chamber which is adapted to receive foam precursor substances, which is arranged within the inner bag volume, which is at least partially and initially delimited against the remainder of the inner bag volume, and which in the non-sealed state of the bag is connected to the open edge portion.
1 . Bag for producing a foam-in-bag dunnage material, comprising, in a non-sealed state of the bag, three straight closed side edges and, in the non-sealed state of the bag, one straight and completely open side edge, the closed and open side edges delimiting an inner bag volume, wherein a bag structure of the bag, in the non-sealed state of the bag, comprises a mixing chamber which is adapted to receive foam precursor substances, which is arranged within the inner bag volume, which is at least partially and initially delimited against the remainder of the inner bag volume, the remainder of the inner bag volume, in the non-sealed state of the bag, being formed by one cohesive chamber, wherein the mixing chamber is at least partially and initially delimited against the remainder of the inner bag volume by means of a weld seal connecting two side walls of the bag to each other, the mixing chamber as well as the remainder in the non-sealed state of the bag both being open by both being connected to the one open side edge to allow to introduce the liquid chemical foam precursor substances through the open edge portion into the mixing chamber, wherein in said non-sealed state of the bag, the bag does not comprise any portion of the inner bag volume other than the mixing chamber and the remainder of the inner bag volume.
2 . The bag according to claim 1 wherein the weld seal has a first portion and a second portion, wherein a seal strength of the second portion is lower than a seal strength of the first portion, such that the mixing chamber is initially fully separate from the remainder of the inner bag volume, and such that by breaking the second portion of the weld seal, a fluid connection is created between the mixing chamber and the remainder of the inner bag volume.
3 . The bag according to claim 1 wherein the mixing chamber has, seen from the side, a conical shape or a funnel shape.
4 . The bag according to claim 1 wherein the mixing chamber comprises mixing elements which provide a labyrinth type path for a fluid mixture moving within the mixing chamber.
5 . The bag according to claim 4 wherein at least some mixing elements are formed by point shape connecting portions of the side walls of the bag at which the side walls are connected to each other, by welding.
6 . The bag according to claim 1 wherein, in a sealed state of the bag, the open edge portion is closed by providing a weld seal such that the inner bag volume and the mixing chamber are sealed against an outside of the bag.
7 . Method for producing foam-in-bag dunnage material, comprising the following steps:
a. providing a bag according to claim 1 in a non-sealed state;
b. providing at least two foam precursor substances into a mixing chamber of the bag through a connection of the mixing chamber to the open edge portion;
c. transforming the bag from its non-sealed state into its sealed state wherein the open edge portion is closed such that the inner bag volume and the mixing chamber are sealed against an outside of the bag;
d. providing a mixing action to the foam precursor substances enclosed within the mixing chamber in order to create a mixture of the foam precursor substances; and
e. allowing the mixture to discharge from the mixing chamber into a remainder of an inner bag volume of the bag.
8 . Method according to claim 7 wherein in step c the transformation is carried out by providing a weld seal along the open edge portion.
9 . Method according to claim 8 wherein in step e the mixture is allowed to discharge from the mixing chamber through an outlet into the remainder of the inner bag volume.
10 . Method according to claim 7 wherein in step e the mixture is allowed to expand from the mixing chamber by breaking a second portion of a weld seal delimiting the mixing chamber against the inner bag volume wherein a seal strength of the second portion is lower than a seal strength of an adjacent first portion of the weld seal.