[0001] The present invention relates to a schoolbag or backpack of the type having at least
one over-the-shoulder carrying strap and more particularly the invention provides
a jointed structure which rigidifies the backpack when in use and reduces its bulk
when in storage.
[0002] Backpacks or rucksacks, equipped with a pair of shoulder straps or with a diagonal
sling strap, are convenient and popular receptacles for luggage allowing travelers
to carry in reasonable comfort whatever belongings they wish to take on their journey.
Both hands of the traveler are left free and a load which would be tiring to carry
by hand in a suitcase is carried more easily by the back. Backpacks are in extensive
use by school-age children, who use them not only as school bags and lunch carriers,
but also as status symbols. Manufacturers, being aware of this potential, produce
brightly colored school bags with many zip-closed compartments, padding to increase
comfort by eliminating load concentration, and further added features and decoration
to attract young customers. By use of light-weight materials the total weight of the
bag is kept to about 1 - 2 kg, depending on size.
[0003] Basically a good quality school bag consists of a semi-rigid back wall anchoring
the shoulder straps, a semi-rigid base at right angles to the back, and a flexible
container taking up the volume defined by the back over the base.
[0004] Bags are available which are completely flexible and these of course present no space
problem. However such bags are not considered to be of good quality because the load
on the back of the wearer is not distributed correctly, and the lack of a base that
is at least semi-rigid results in inconvenience during loading and in distortion of
books during use.
[0005] While of low weight, the backpack with a rigidified base is bulky and presents a
problem for manufacturers and wholesalers who need to store large quantities before
the start of a new school year. Transport, particularly for export, is also expensive
for the same reason. Perhaps the most pressing reason to overcome the problem of bulk
is the reluctance of retailers to stock sufficient quantities and different styles,
colors and sizes. There are different styles for boys and girls. On the one hand,
at retail outlets there is fierce competition for shelf and display space, yet sales
depend on retailers being able to carry enough stock to meet the demands of a child
who has decided that he wants, for example, a green, size 3 school bag decorated with
space invaders.
[0006] Although no directly similar prior art could be found, the following disclosures
are indicative of the nearest related work to the subject of the invention.
[0007] In US Patent no. 4,356,942 Hayes discloses a rucksack with an internal rigid frame,
attached to an external plate. The plate allows different width spacing for the shoulder
straps.
[0008] A backpack capable of being collapsed into a satchel orientation is disclosed by
Fresco in US Patent no. 5,609,278. The backpack has an upper and a lower compartment,
and can be secured over the wheel sides of a bicycle in pannier orientation.
[0009] A school bag which can be expanded is seen in US Design Patent Des.377,415. A zipper
extending around three sides of the bag can be opened to extend bag thickness.
[0010] It is therefore one of the objects of the present invention to provide a method of
compacting a school bag of the backpack type in order to reduce required storage volume
when not in use.
[0011] It is a further object of the present invention to achieve back rigidity and bulk
reduction while adding no more than 200 grams weight to an average size school bag.
[0012] The present invention achieves the above objects by providing a school bag or backpack
of the type having a back, a bottom, a flexible receptacle and at least one over-the-shoulder
carrying strap, further provided with a bi-stable structure comprising a rigidifying
back element articulated to a rigidifying base to allow stable upright positioning
on a horizontal surface while loading and unloading the contents of the backpack,
the bi-stable structure being inserted into the backpack during manufacture. The structure
is made to assume a first stable position in which the rigidifying base is folded
back against the rigidifying back element and when thus disposed in the backpack to
retain the bottom thereof folded up towards the back of the backpack reducing the
bulk thereof, and a second position in which the two rigidifying members define a
substantially stable right-angle configuration therebetween thereby to also maintain
such a configuration between the back and the bottom of the backpack.
[0013] In a preferred embodiment of the present invention there is provided a school bag
or backpack wherein the rigidifying base is attached to the bottom of the backpack.
[0014] In a most preferred embodiment of the present invention there is provided a school
bag or backpack wherein the rigidifying back element and the rigidifying base are
of substantially U-shaped configuration and wherein the two spaced-apart arm ends
of a first of the elements and the two spaced-apart arm ends of the second element
are respectively interconnected by a pair of articulating joints.
[0015] The invention will now be described in connection with certain preferred embodiments
with reference to the following illustrative figures so that it may be more fully
understood.
[0016] With specific reference now to the figures in detail, it is stressed that the particulars
shown are by way of example and for purposes of illustrative discussion of the preferred
embodiments of the present invention only and are presented in the cause of providing
what is believed to be the most useful and readily understood description of the principles
and conceptual aspects of the invention. In this regard, no attempt is made to show
structural details of the invention in more detail than is necessary for a fundamental
understanding of the invention, the description taken with the drawings making apparent
to those skilled in the art how the several forms of the invention may be embodied
in practice.
[0017] In the drawings:
FIG. 1 is an elevational view of a preferred embodiment of the backpack according
to the invention;
FIG. 2 is an elevational view of the same embodiment in its compacted configuration;
FIG. 3 is a detail view of an embodiment where the bi-stable structure is attached
to the bottom of the backpack;
FIG. 4 is a partially exploded view of the bi-stable structure;
FIG. 5 is an elevational view of the bi-stable structure in its folded configuration;
and
FIG. 6 is a perspective view of the plastic joint housing.
[0018] There is seen in FIGS. 1 and 2 a backpack 10 of the type having a back 12, a bottom
14, a flexible receptacle 16 and a pair of spaced-apart over-the-shoulder carrying
straps 18. Also seen in the figure are a bag cover 20 and zipper closures 22 for bag
compartments.
[0019] A bi-stable structure 24 comprising a rigidifying back element 26 articulated to
a rigidifying base 28 is inserted into the school bag 10 during manufacture. The structure
24 facilitates stable upright positioning on a horizontal surface 30 while loading
and unloading the contents of the backpack.
[0020] In FIG. 1 the two rigidifying members 26, 28 define a substantially stable right-angle
configuration therebetween. Thereby the backpack is also brought to take up and maintain
a right-angle configuration between the back 12 and the bottom 14 thereof.
[0021] When the backpack 10 is empty as seen in FIG. 2, the bi-stable structure 24 can be
made to assume a stable position in which the rigidifying base 28 is folded back against
the rigidifying back element 26. When thus disposed the structure 24 retains the bottom
14 of the backpack folded up towards the back 12 thereof. Thus the bulk of the backpack
is greatly reduced.
[0022] With regard to the rest of the figures, similar reference numerals have been used
to identify similar parts.
[0023] Referring now to FIG. 3, there is seen a detail of backpack 32 wherein the rigidifying
base 28 is attached to the bottom 14 of the backpack. This is achieved in the shown
embodiment by inserting extensions 30 of four thermoplastic feet 32 through apertures
34 in the rigidifying base 28, spacer block 33 and the bottom 14 of the backpack 32.
The upper ends of the extensions 30 are heat-swaged for fast permanent fastening of
the bi-stable structure 24 to the backpack 32. The inner lining 35 of the backpack
covers attachment arrangement.
[0024] FIG. 4 illustrates the details of the bi-stable structure 24. Both the rigidifying
back element 26 and the rigidifying base 28 are of light metal tubing of substantially
U-shaped configuration. The two spaced-apart arm ends of the back element 26 and the
two spaced-apart arm ends of the rigidifying base 28 are respectively interconnected
by a pair of articulating joints 36, which will be further described with reference
to FIG. 6. The back element 26 is provided with solid end pieces 38, a spacer bar
40 stabilizes the structure and a variety of appropriate fasteners 42 interconnect
the components.
[0025] The main components of the bi-stable structure 44 are suitably made of a light-weight
metal alloy such as aluminium. This choice produces a strong structure of total weight
of less than 190 gram. For weight-critical applications, replacement of the aluminium
by magnesium reduces total structure weight to under 140 gram.
[0026] Seen in FIG. 5 is the bi-stable structure 24, described with reference to FIG. 4,
shown here in its folded state.
[0027] Referring now to FIG. 6, there is depicted a detail of an articulated joint 36. The
solid end pieces 38 seen in FIG. 4 are pivoted about the hole 46. An edge lip 48 is
positioned to press against - but to allow passage of the solid end pieces 38, when
the structure is between folded and deployed at 90 degrees. At the end positions (folded
and deployed) no rotational resistance is exerted. The friction provided by the edge
lip 48 is augmented by side friction pads 50, which press against the sides of the
end pieces 38.
[0028] It is realized that there are many other types of detent devices which could be used
for retaining the structure in the two required positions until a substantial torque
is applied to move the arms out of their existing orientation. Nevertheless it is
considered that the joint described in the present specification is advantageous as
providing low weight and low costs.
[0029] It will be evident to those skilled in the art that the invention is not limited
to the details of the foregoing illustrative embodiments and that the present invention
may be embodied in other specific forms in the limit of the appended claims.
1. A school bag (10) or backpack of the type having a back, a bottom, a flexible receptacle
and at least one over-the-shoulder carrying strap, further provided with a bi-stable
structure (24) comprising a rigidifying back element (26) articulated to a rigidifying
base (28) to allow stable upright positioning on a horizontal surface while loading
and unloading the contents of said backpack (10), said bi-stable structure being inserted
into said backpack during manufacture, and which structure is made to assume a first
stable position in which said rigidifying base (28) is folded back against said rigidifying
back element (26) and when thus disposed in said backpack to retain the bottom (14)
thereof folded up towards said back (12) of said backpack reducing the bulk thereof,
and a second position in which said two rigidifying members define a substantially
stable right-angle configuration therebetween thereby to also maintain such a configuration
between said back (12) and said bottom of said backpack.
2. A school bag or backpack (10) according to claim 1, wherein said rigidifying base
(28) is attached to said bottom (14) of said backpack.
3. A school bag or backpack (10) according to claim 1, wherein said rigidifying back
element (26) and said rigidifying base (28) are of substantially U-shaped configuration
and wherein the two spaced-apart arm ends of a first of said elements and the two
spaced-apart arm ends of the second element are respectively interconnected by a pair
of articulating joints (36).
4. A school bag or backpack (10) according to claim 1, wherein said rigidifying back
element (26) and said rigidifying base (28) are made of a light-weight metal alloy.
5. A school bag or backpack (10) according to claim 4, wherein said metal is aluminium.
6. A school bag (10) according to claim 1, wherein the total weight of said bi-stable
structure (24) is less than 190 gram.
1. Schultasche (10) oder Rucksack des Typs, der eine Rückseite, einen Boden, einen flexiblen
Aufnahmeraum und wenigstens einen über der Schulter getragenen Riemen besitzt und
ferner versehen ist mit einer bistabilen Struktur (24), die ein versteifendes Rückenelement
(26) umfasst, das an einer versteifenden Basis (28) angelenkt ist, um eine stabile
aufrechte Positionierung auf einer horizontalen Oberfläche zu ermöglichen, wenn die
Inhalte des Rucksacks (10) eingeladen und ausgeladen werden, wobei die bistabile Struktur
während der Herstellung in den Rucksack eingesteckt ist und wobei die Struktur so
beschaffen ist, dass sie eine erste stabile Position einnimmt, in der die versteifende
Basis (28) gegen das versteifende Rückenelement (26) zurückgeklappt ist und sie, wenn
so im Rucksack angeordnet, dessen Boden (14) nach oben zur Rückseite (12) des Rucksacks
umgeklappt hält, um sein Volumen zu verringern, und eine zweite Position einnimmt,
in der die zwei versteifende Elemente zwischen sich eine im Wesentlichen stabile rechtwinklige
Konfiguration definieren, wodurch eine solche Konfiguration zwischen der Rückseite
(12) und dem Boden des Rucksacks ebenfalls aufrechterhalten wird.
2. Schultasche oder Rucksack (10) nach Anspruch 1, bei der die versteifende Basis (28)
am Boden (14) des Rucksacks befestigt ist.
3. Schultasche oder Rucksack (10) nach Anspruch 1, bei dem das versteifende Rückenelement
(26) und die versteifende Basis (28) eine im Wesentlichen U-förmige Konfiguration
besitzen und bei dem die zwei beabstandeten Armenden eines ersten der Elemente und
die zwei beabstandeten Armenden des zweiten Elements durch ein Paar Gelenke entsprechend
miteinander verbunden sind.
4. Schultasche oder Rucksack (10) nach Anspruch 1, bei dem das versteifende Rückenelement
(26) und die versteifende Basis (28) aus einer Metalllegierung mit geringem Gewicht
hergestellt sind.
5. Schultasche oder Rucksack (10) nach Anspruch 4, bei dem das Metall Aluminium ist.
6. Schultasche (10) nach Anspruch 1, bei der das Gesamtgewicht der bistabilen Struktur
(24) geringer als 190 Gramm beträgt.
1. Sac d'écolier (10) ou sac à dos du type comportant un dos, un fond, un réceptacle
souple et au moins une sangle de portage passant par-dessus l'épaule, muni de plus
d'une structure bistable (24) comprenant un élément rigidifiant le dos (26) articulé
sur une base rigidifiante (28) pour permettre un positionnement vertical stable sur
une surface horizontale lors du vidage et remplissage du contenu dudit sac à dos (10),
ladite structure bistable étant insérée dans ledit sac à dos pendant la fabrication,
et laquelle structure étant réalisée pour prendre une première position stable dans
laquelle ladite base rigidifiante est repliée contre ledit élément de dos rigidifiant
(26) et lorsqu'elle est ainsi disposée dans ledit sac à dos pour maintenir le fond
(14) replié vers ledit dos (12) dudit sac à dos réduisant sa masse, et une seconde
position dans laquelle les deux dits éléments rigidifiants définissent une configuration
sensiblement stable à angle droit entre eux pour également maintenir ladite configuration
entre ledit dos (12) et ledit fond dudit sac à dos.
2. Sac d'écolier ou sac à dos (10) selon la revendication 1, dans lequel ladite base
rigidifiante (28) est fixée sur ledit fond (14) dudit sac à dos.
3. Sac d'écolier ou sac à dos (10) selon la revendication 1, dans lequel ledit élément
de dos rigidifiant (22) et ladite base rigidifiante (28) ont une configuration sensiblement
en forme de U et dans lequel les deux extrémités de bras espacées entre elles d'un
premier desdits éléments et les deux extrémités de bras espacées entre elles du second
élément sont respectivement reliées entre elles par une paire de joints d'articulation
(36).
4. Sac d'écolier ou sac à dos (10) selon la revendication 1, dans lequel ledit élément
de dos rigidifiant (26) et ladite base rigidifiante (28) sont réalisées en un alliage
métallique de poids léger.
5. Sac d'écolier ou sac à dos (10) selon la revendication 4, dans lequel ledit métal
est de l'aluminium.
6. Sac d'écolier (10) selon la revendication 1, dans lequel le poids total de ladite
structure bistable (24) est inférieur à 190 grammes.