[0001] This .patent application for an industrial utility model, concerns a knapsack type
bag with a closing seal, in plastic or paper material. Closing of this bag is automatically
effected by pulling the string which enables the said bag to be gripped and more specifically
placed on the shoulders like a knapsack.
[0002] The model, according to the invention, is absolutely brand new and can be included
in the range of plastic or paper bags in which purchased goods are normally consigned
nowadays. It is manufactured, following current production techniques, from a tubular
sheet, closed at one end underneath a supporting base, which actually makes up the
bearing structure of the bag, which is provided with suitable closing and/or gripping
means at its open edges.
[0003] In certain models of so-called drawstring bags, the closing and gripping means are
both made up of a string which is passed through holes especially made along the upper
edge of the bag, which closes and curls up when the said string is pulled.
[0004] This string is long enough for the ends to be externally hooked to the bag at a particular
fixing point placed on the outside of the bag base. In this case, the bag can be carried
on the shoulder.
[0005] The aim of this invention is to create a new bag model, characterized in that the
said closing and support string is hooked to the base, in such a way that it can act
as a double strap allowing the bag to be placed on the shoulders tike a kind of knapsack.
A closing seal is also provided which is automatically closed at the bag's open edges,
each time the said string is pulled by the user and under the weight of the full bag
itself.
[0006] According to this model, the bag, as far as its shape is concerned, is one of the
type of shopping bags which .are conventionally manufactured like normal bags, in
which the base is obtained by folding a tubular sheet longitudinally, in two different
dihedrals transversally opposite each other which both start at the same central plane,
and by welding the end of the tubular sheet along a diametrical line. In this way
the base comes to an end at a sharp edge and if the bag is empty it has a squashed
shape, which when full takes on the form of a parallelepiped with a quadrangular base.
[0007] For the first time ever, this invention requires that a seal be applied at the opening
of the bag, which goes over the top of the two opening edges of the bag and clamps
them one against the other under pressure each time a string is pulled, the ends of
which are knotted externally at the base of the bag at two distinct, well-spaced points,
after first being threaded through three pairs of holes made for this very purpose
on the abovementioned closing seal and on the two open edges of the bag.
[0008] For further clarity of explanation, the description of the invention continues with
reference to the attached drawings, reproduced for illustrative and not restrictive
purposes, in which:
- Figure 1 is an axonometric schematic representation of the bag according to the
invention, seen from one side;
- Figure 2 is an axonometric schematic representation of the bag according to the
invention, seen from the opposite side to Fig. 1;
- Figure 3 is an axonometric schematic representation of another preferred embodiment
of the bag, according to the invention, seen from one side;
- Figure 4 is an axonometric, schematic representation of the version in Figure 3,
seen from the opposite side to Figure 3.
[0009] With reference to figures 1 and 2, it can be noted that the knapsack type bag (1),
in its preferred form of embodiment, is made up of a single sheet (2), in plastic
or paper material, preferably already tubular, internally provided with a reinforcement
sheet (3) at its base, and with a closing seal (4) at the opening which is externally
glued to the top edge of one of the sides (la) of the bag (1) and folded over and
above the top edge of the other side (lb) beside and opposite the first side.
[0010] In the upper part of the bag, pairs of corresponding through holes are made into
which a string (5) is threaded. The ends of this string are knotted at two distinct
and well-spaced points at the base of the side (la) at which point two through holes
are made which are crossed by the two ends of the string (5). These are then made
to pass through corresponding holes provided on the support base (3) and on the sheet
(2) which is folded and glued underneath the base (3).
[0011] The string (5) is also threaded through the closing seal (4), the flap of which has
two holes on it, with identical center distance and arrangement to those along the
top edges of the sides (la) and (lb) of the bag (1), so that when the string (5) is
pulled the closing seal is automatically shut against the outside of the top edge
of the side (lb) which is squashed together with the closing seal, along the top edge
of side (la).
[0012] On the attached drawings, number (6) shows normal support strips which are usually
applied along the open edges of the bag so as to make it more difficult for the sheet
(2) to be torn where the holes are for the threading through of the string (5).
[0013] In figures 3 and 4, a simplified version of the model according to the invention
is represented, using the same axonometric views and the same reference numbers, in
which the closing seal (4) has .been eliminated, while maintaining the knapsack type
arrangement of the bag which is a characteristic of the model in question.
1) Knapcack type bag, with closing seal, in plastic or paper material, the base of
which is obtained by folding a tubular sheet (2) longitudinally, according to two
transversally opposite dihedrals which both start on the same central plane and by
welding the end of the tubular sheet along a diametrical line. Said bag is characterized
in that it has a string (5) the ends of which are knotted at two distinct, well-spaced
points at the base of one side (le) of the bag (1) at which there are through holes
also on the support base (3) with which the bottom of the bag is traditionally reinforced.
The abovementioned string (5) is threaded through two pairs of corresponding holes,
each pair being made along the top edge of the two sides (1a) and (lb) of the bag
(1) which are beside and opposite each other, so that when the string (5) is pulled
the bag (1) is automatically closed, by means of the fact that the top edges of the
said sides (la) and (lb) are brought together and shut. 2) Knapsack type bag with
closing seal, in plastic or paper material, according to the previous claim, characterised
in that it has a closing seal (4) applied on the outside of the top edge of one side
(la) of the bag (1) and folded over and above the other top edge of the other side
(lb) of the bag (1). On the flap of this closing seal (4), there are two holes with
identical center distance and arrangement to those along the two open edges of the
bag (1) so that the string (5) can also be threaded through the said seal, which is
automatical-1y closed and squashed against the outside of the top edge of the side
(lb) as soon as the string (5) is pulled.