Patent Description:
Currently, backpacks having a bag for housing various objects and with a number of straps for hanging them upon the shoulders, so that the bag is positioned against the back, are widely known.

Specifically, document <CIT> describes a set for a backpack that includes a pair of straps, a pair of right-angled webbing rings and a clasp. The right-angled webbing rings enable the straps to be adjusted across the chest of the user by pulling the extremities of the strap that are around the waist of the user and fastening the clasp. The right-angled webbing rings keep the tension of the straps on the chest of the user when the clasp is loosened, which prevents the package from sliding down the back of the user. The straps are crossed and tied together.

Document <CIT> describes embodiments of a bag, such as a backpack, having a self-adjustable carrying strap system and methods to manufacture said bag. Essentially, the bags described in this document compress a connector plate that connects to each strap, although it is explicitly described that each strap can freely move through the plate with respect to the other strap.

The previous documents do not have features directly aimed at improving the ergonomics of the backpack, and improving the comfort of carrying the same by the user.

Document <CIT> describes a lightweight ergonomic backpack load carrying system adapted to anatomically distribute a backpack load from the shoulders of a user onto the waist region thereof. The backpack load carrying system includes a waist support contoured to fit the waist of a user. A waist support frame extends from the waist support to a return connection. A backpack support frame extends from the return connection forming an acute angle to the waist support frame. A securing mechanism is adapted to secure the backpack load carrying system onto a backpack. Another example of a prior art backpack is disclosed in <CIT>.

This document describes the problem of the lack of ergonomics of backpacks of the state of the art and contains a technical analysis of the forces that are applied to the body of a user of non-ergonomic backpacks. However, the solution proposed in this document to solve said problem is totally different from that of the present application, since it proposes a device to be used in combination with conventional, non-ergonomic backpacks.

The backpack object of this invention exhibits features that enable a large portion of the load carried by the user of the backpack to be applied in the area of the middle dorsal region substantially located at the centre of the back and on the interscapular area in the upper dorsal spine, and in the area where the dorsal region curves toward the cervical region of the user. Due to said curve and in particular to the features of the fastening straps of the bag of the backpack and to the special configuration of the area where the straps connect to the upper end of the bag, said area of the middle dorsal region receives a great portion of the load, partly unloading the load upon the shoulders of the user, which receive said load through the backpack straps in the form of a first component of rear traction and a second component of weight, and the frontal portion of the user which, by means of said straps, receives a third component of the load in the form of frontal traction.

By enabling the load to be better distributed along the portions of the body that contact the straps of the backpack, the use of the backpack of the invention can improve the posture of the user and inhibit the generation of musculoskeletal pains and other adverse effects associated with the use of non-ergonomic backpacks.

The backpack of this invention is defined by claim <NUM>, comprising: a bag having one frontal side to rest against the back of the user, and a number of supporting straps, of adjustable length, comprising: a front section attached to a lower area of the corresponding side of the bag; an intermediate section forming an area for resting upon the shoulders of the user, and a rear section attached to an upper end of the bag.

According to the invention, the rear sections of the straps converge toward a crossing area located between the upper end of the bag and the intermediate section for resting upon the shoulders of the user.

Said rear sections of the straps are attached to the upper end of the bag by means of a connecting end section, with a convergent-divergent configuration in the downward direction, and the lower end of which is partially housed inside the bag and attached to the frontal side of said bag.

The divergence of said connecting end section toward the area where it attaches to the bag enables said connecting end section to exhibit at the bottom a width suitable for balancing the weight of the backpack on the middle plane of the body and specifically on the crossing area, avoiding an imbalance or offset of the bag toward one or the other side of the body of the user.

The convergence of the rear sections of the straps toward the aforementioned area where they cross and the distance of said crossing area, in an ascending vertical direction, with respect to the upper end of the bag due to the interposition of the connecting end section, enables a significant portion of the weight of the backpack to be applied to the interscapular area in the upper dorsal spine, which gives the backpack an ergonomic and easy-to-carry nature.

To achieve this ergonomic advantage, the backpack must be positioned correctly with respect to the body of the user; to do so and according to the invention, a feature of the invention is that the straps have in the intermediate section a number of centring marks for the area for resting upon the shoulders of the user.

Adapting the position of said centring marks upon the shoulders of the user is easily carried out by varying the length of the straps with respect to the lower area of the sides of the bag, where the backpack has conventional clasps, suitable for the adaptable coupling of the straps.

In this way, a balanced distribution of the total weight of the backpack on the different areas for resting against the body of the user is achieved.

One feature of the invention is that the connecting end section for connecting the straps to the upper end of the bag has a height portion comprised between <NUM> and <NUM> inside the bag, which enables a strong connection between both elements to be established, by means of different conventional means: sewing, gluing, riveting or the like.

Other optional dimensional features aimed at achieving a correct positioning of the backpack on the body and the aforementioned ergonomic advantages are:.

It is worth mentioning that the connecting end section, responsible for connecting the rear sections of the straps to the upper end of the bag, can exhibit different configurations and be formed: either by an extension of the straps forming the frontal, intermediate and rear sections, or by an independent part, generally X-shaped, which defines the crossing area and which is attached by the upper flanges thereof to the rear sections of the straps and by the lower flanges thereof to the upper end of the bag.

In the first embodiment, said connecting end section comprises: - a crossing area, wherein the rear sections of the straps are superimposed in an oblique direction, forming the aforementioned angle of <NUM>° to <NUM>°, and connected to each other, either by means of sewing, gluing, riveting or any other suitable technique, and - a number of end branches formed by a number of extensions of the rear sections that exceed said crossing area.

In this embodiment, it is envisaged that the end branches of the straps are connected to each other by means of a transversal strap section that defines, together with said end branches, a triangular surface with a central hole. The purpose of this transversal strap section is to reinforce the area where the straps connect to the upper end of the bag of the backpack.

According to one embodiment of the invention, the generally X-shaped independent part defines the area where they cross and has the lower flanges thereof connected, defining a continuous triangular lower area. As in the previous case, this continuous triangular area has the purpose of reinforcing the independent part in the area where it connects to the upper end of the bag of the backpack.

According to one embodiment of the invention, the end branch and the rear section of the strap corresponding to one same side, left or right, of the backpack, define a second angle of convergence between each other, toward the area where they cross, comprised between <NUM>° and <NUM>°. In this way, the correct positioning of the backpack against the body and the aforementioned ergonomic advantages are further improved. It is important to note that the sum of the angle of convergence and the second angle of convergence can be <NUM>° or different.

As a complement to the description provided herein, and for the purpose of helping to make the features of the invention more readily understandable, the present specification is accompanied by a set of drawings which, by way of illustration and not limitation, represent the following:.

In <FIG> and <FIG>, the ergonomic backpack comprises: a bag (<NUM>) having one frontal side (<NUM>) to rest against the back of the user, and a number of straps (2a, 2b) of adjustable length, for hanging from the shoulders of the user.

Said straps (2a, 2b) comprise: a front section (<NUM>) attached to a lower area of the corresponding side (12a, 12b) of the bag (<NUM>) by means of a number of clasps (<NUM>) suitable for adjusting the length thereof; an intermediate section (<NUM>) forming an area for resting upon the shoulders of the user, and a rear section (<NUM>) attached to an upper end (<NUM>) of the bag (<NUM>) by means of sewing, riveting, gluing or any other technique that enables a strong and lasting attachment to be provided.

The rear sections (<NUM>) of the straps (2a, 2b) converge toward a crossing area (<NUM>) located between the upper end (<NUM>) of the bag and the intermediate section (<NUM>) for resting upon the shoulders of the user.

The aforementioned rear sections (<NUM>) of the straps are attached to the upper end (<NUM>) of the bag (<NUM>) by means of a connecting end section, generically referenced as (T) in the different embodiments thereof.

Said connecting end section (T) exhibits a convergent-divergent configuration in the downward direction, with the lower end thereof partially housed inside the bag (<NUM>) and attached to the frontal side (<NUM>) of said bag (<NUM>).

The straps (2a, 2b) and the connecting end section (T) for connecting to the upper end (<NUM>) of the bag (<NUM>) are configured to enable a large portion of the load carried by the user to be applied in the area of the middle dorsal region, substantially located at the centre of the back and on the interscapular area in the upper dorsal spine, and in the area where the dorsal region curves toward the cervical region of the user, as shown schematically in <FIG> with the representation of the components of the forces acting on that specific area. This achieves an ergonomics that provides the user with a high level of comfort when carrying the backpack.

The straps (2a, 2b) have in the intermediate section (<NUM>) centring marks (<NUM>) for the area for resting upon the shoulders of the user. The correct positioning of the centring marks (<NUM>) upon the shoulders of the user is adapted by varying the length of the straps (2a, 2b) in the area where they attach to the clasps (<NUM>).

This adaptation enables the user to correctly position the backpack to achieve the aforementioned ergonomics and comfort, since in the event that the centring marks (<NUM>) are excessively moved backwards or forwards with respect to the shoulders, a variation of the distribution of the forces and of the areas for resting against the body occurs, and consequently a decrease or loss of the ergonomics intended by the invention.

In order to obtain said ergonomics, the straps and the rear connecting area for connecting to the bag must have certain dimensional features, referenced in <FIG>.

Specifically, the connecting end section (T) has a height portion (h1) comprised between <NUM> and <NUM> inside the bag (<NUM>).

The rear sections (<NUM>) of the straps (2a, 2b) define an angle (b) of convergence between them toward the crossing area (<NUM>) comprised between <NUM>° and <NUM>°, thereby guaranteeing the correct positioning thereof against the interscapular area in the upper dorsal spine of the user; the crossing area (<NUM>) where they cross is distanced from the upper end (<NUM>) of the bag (<NUM>) by a height (h2) comprised between <NUM> and <NUM> and the distance (d) between the centring marks (<NUM>) upon the shoulders and the area (<NUM>) where they cross is comprised between <NUM> and <NUM>.

As mentioned above, the connecting end section (T) for connecting the straps (2a, 2b) to the upper end (<NUM>) of the bag (<NUM>) can exhibit different configurations, in any case maintaining, in the downward direction, a converging shape up to the crossing area (<NUM>) and a diverging shape, of increasing width, below said crossing area (<NUM>).

In the exemplary embodiment shown in <FIG>, said connecting end section (T) for connecting to the bag (<NUM>) comprises: a crossing area (<NUM>), wherein the rear sections (<NUM>) of the straps are superimposed in an oblique direction and connected to each other, and a number of end branches (<NUM>) formed by extensions of the rear sections (<NUM>). Said end branches (<NUM>) exceed the crossing area (<NUM>) toward the lower area and, as shown in <FIG>, penetrate the upper end (<NUM>) of the bag (<NUM>), attaching to the frontal side (<NUM>) of the bag by any suitable means to provide a strong and lasting attachment.

Said end branches (<NUM>) can be separated, by way of an inverted V as shown in <FIG>; be connected to each other by means of a transversal strap section (<NUM>) that defines together with said end branches (<NUM>) a triangular surface with a central hole, as shown in <FIG>.

The function of this transversal section (<NUM>) is to provide additional reinforcement in the area where the connecting end section (T) connects to the bag of the backpack, as shown in <FIG> and <FIG>.

In the embodiment variant shown in <FIG>, the connecting end section (T) is formed by an independent part (<NUM>), generally X-shaped, which defines the crossing area (<NUM>) and which is attached by the upper flanges (<NUM>) thereof to the rear sections (<NUM>) of the straps (2a, 2b) and by the lower flanges (<NUM>) thereof to the upper end (<NUM>) of the bag (<NUM>).

In the embodiment variant shown in <FIG>, the connecting end section (T) for connecting to the bag is also formed by an independent part (<NUM>), generally X-shaped, with the particularity that the lower flanges thereof are connected, defining a continuous triangular lower area (<NUM>), the purpose of which is to reinforce the independent part (<NUM>) in the area where it connects to the bag (<NUM>).

It is worth mentioning that both the straps (2a, 2b) and the connecting end section (T), in the different configurations thereof, can be formed by a textile material, or leather, or plastic or polymer or combinations thereof, and exhibit a monolayer or multilayer structure, including intermediate areas padded with foam, or air, or any other material with a shock-absorbing effect.

Likewise, it is important to mention that <FIG> shows the end branch (<NUM>) and the rear section (<NUM>) of the strap corresponding to one same side, left or right, of the backpack, defining a second angle (a) of convergence between them, toward the crossing area, comprised -in a very specific first embodiment- between <NUM>° and <NUM>°. In other even more preferred embodiments, the second angle (a) is between <NUM>° and <NUM>°.

Likewise, it should be mentioned that in a very preferred embodiment, the height portion (h1) is between <NUM> and <NUM>, the angle (b) of convergence is between <NUM>° and <NUM>°, the height (h2) is between <NUM> and <NUM>, the distance (d) is between <NUM> and <NUM>. This further improves the ergonomics of the backpack. In another even more preferred embodiment, which complies with the previous one, the second angle (a) is additionally between <NUM>° and <NUM>°.

A number of numerical parameters of a first specific ideal example, a second specific ideal example and a third specific ideal example of the ergonomic backpack, are indicated in the following table:.

Claim 1:
An ergonomic backpack, comprising: a bag (<NUM>) having one frontal side (<NUM>) to rest against the back of the user, and a number of supporting straps (2a, 2b) of adjustable length, comprising: a front section (<NUM>) attached to a lower area of a corresponding side (12a, 12b) of the bag (<NUM>); an intermediate section (<NUM>) forming an area for resting upon the shoulders of the user, and a rear section (<NUM>) attached to an upper end (<NUM>) of the bag (<NUM>); wherein the rear sections (<NUM>) of the straps (2a, 2b) converge toward a crossing area (<NUM>) located between the upper end (<NUM>) of the bag and the intermediate section (<NUM>) for resting upon the shoulders of the user; said rear sections are attached to the upper area of the bag (<NUM>) by means of a connecting end section (T), with a convergent-divergent configuration in the downward direction, and the lower end of which is partially housed inside the bag (<NUM>) and attached to the frontal side (<NUM>) of said bag (<NUM>); wherein:
- the connecting end section (T) comprises a number of end branches (<NUM>) formed by a number of extensions of the rear sections (<NUM>) that exceed the crossing area (<NUM>), wherein the rear sections (<NUM>) of the straps are superimposed in an oblique direction and connected to each other, and a number of end branches (<NUM>) formed by a number of extensions of the rear sections (<NUM>) that exceed said crossing area (<NUM>), and wherein the end branches (<NUM>) of the straps (2a, 2b) are connected to each other by means of a transversal strap section (<NUM>) that defines together with said end branches (<NUM>) a triangular surface with a central hole; or
- the connecting end section (T) is formed by an independent part (<NUM>), generally X-shaped, which defines the crossing area (<NUM>) and which is attached by upper flanges (<NUM>) thereof to the rear sections (<NUM>) of the straps (2a, 2b) and by lower flanges (<NUM>) thereof to the upper end (<NUM>) of the bag (<NUM>).