Field of the invention

the present invention relates to the suitcases market. In the present description and the claims which follow, the term "suitcase" is intended to refer in general to a container of predetermined shape intended for transporting personal effects or other objects on journeys in a protected fashion.

More particularly, but not exclusively, the invention relates to suitcases intended to be transported predominantly by pulling or pushing, commonly called "trolleys". Prior art

Known suitcases are normally made of rigid materials or soft materials. In the first case, the material itself allows the desired shape and bearing structure to be conferred on the suitcase, whereas in the second case, if the suitcase is required substantially to keep a predetermined shape and to have a bearing structure, additional, rigid reinforcing members or frames, usually made of plastic materials, wood or metal must be used.

Suitcases made of rigid material are sturdy and assure maximum protection to their contents. However, they weigh a considerable amount and, specifically because of the rigid structure, there are more subject to permanent damage, such as scratches, abrasions etc following knocks or other external stresses. Such damage has a negative impact on the aesthetic appearance of the suitcase and, in the worst cases, may also compromise the functional capacity thereof.

Suitcases made of a soft material with additional reinforcing members are generally lower in weight than suitcases of equal capacity made of rigid material and, due to the greater resilience of the materials used, are less subject to permanent damage due to knocks. However, the weight of the suitcases is still negatively influenced by the need to use additional, rigid reinforcing members. Furthermore, these reinforcing members may be subject to deformation or tears which can compromise the functional capacity of the suitcase.

The weight reduction, while representing a primary objective in suitcase manufacture, cannot - particularly in suitcase types such as trolleys - be disassociated from maintaining a stability of form and structural rigidity adequate to guarantee the functional capacity of the suitcase itself. Summary of the invention

The aim of the present invention is to provide a suitcase, in particular a trolley, having an improved structure which, while ensuring a stability of form and structural rigidity comparable to those of known suitcases made of soft material and equipped with additional reinforcing structure, enables a reduction in weight to be obtained by comparison with this type of known suitcases.

This aim is achieved by means of a suitcase according to claim 1 , as well as by means of a shell for a suitcase body in accordance of claim 9 and a cut piece of flexible material for making said shell in accordance with claim 10.

In to a first aspect, the invention therefore relates to a suitcase with a suitcase body at least partially formed by a shell comprising a first main surface and at least three lateral surfaces extending at an angle from sides of said first main surface, wherein:

said first main surface and said at least three lateral surfaces belong to a single cut piece of flexible sheet-like material, and

said first main surface and said at least three lateral surfaces are shaped and said at least three lateral surfaces are at least partially joined to one another so that said shell forms a self-supporting structure.

Advantageously, due to use of a suitcase body at least partially formed by a shell configured in such a way as to present characteristic self-supporting features even if made of flexible material, it is possible to avoid, or at least considerably limit, the use of additional rigid reinforcing structures for conferring on the suitcase the desired stability of form and structural rigidity, with a consequent appreciable reduction in weight.

The suitcase of the invention therefore combines all the advantageous features typical of suitcases of the known art made of soft material with an additional reinforcing structure - in particular the possibility of absorbing knocks without sustaining permanent damage, and a stability and structural rigidity such as to permit substantial shape retention -, at an extremely contained weight.

The weight reduction obtainable by means of the present invention is especially advantageous in the case of suitcases intended for use characterised by mainly direct propulsion on the part of the user, and over long distances, such as, in particular, trolleys and/or suitcases which satisfy the requirements for use as hand baggage in air travel.

Preferred features of the suitcase of the invention are the subject of dependent claims 2-8, the content of which is included here in its entirety for reference.

In a second aspect, the invention relates to a shell for a suitcase body of a suitcase, comprising a main surface and at least three lateral surfaces extending at an angle from sides of said first main surface, wherein:

said main surface and said at least three lateral surfaces belong to a single cut piece of flexible sheet-like material, and

- said main surface and said at least three lateral surfaces are shaped and said at least three lateral surfaces are at least partially joined to one another so that said shell forms a self-supporting structure.

Such a shell enables all the advantageous features described above with reference to the first aspect of the invention to be conferred on a suitcase.

In a further aspect, the invention relates to a cut piece of flexible sheet-like material shaped to form a shell having the above-mentioned features.

Brief description of the drawings

Further features and advantages of the present invention will be clearer from the following detailed description of a preferred embodiment thereof, which description is provided here in what follows by way of non-limiting illustration, with reference to the attached drawings, wherein:

- Fig. 1 is a diagrammatic prospective view of a suitcase according to the invention;

- Fig. 2 is a diagrammatic prospective view of a shell forming part of the suitcase body of the suitcase in Fig. 1 ;

- Fig. 2a is a diagrammatic front view of the shell of Fig. 2;

- Fig. 2b is a diagrammatic top view of the shell of Fig. 2, and

- Fig. 3 is a diagrammatic planar view of a cut piece of flexible material shaped to manufacture the shell of Fig. 2.

Detailed description of a preferred embodiment of the invention

In Fig. 1 reference numeral 1 indicates overall a suitcase according to the present invention. By way of non-limiting example, the suitcase 1 shown in Fig. 1 is in particular a trolley.

The trolley 1 comprises a suitcase body 2, partially formed by a shell 10 of flexible material, shown in greater detail in Figs. 2, 2a e 2b.

As can be seen in particular in Fig. 2, the shell 10 comprises a first main surface 101 and at least three lateral surfaces 102, 103 and 104 extending at an angle of from sides of the first main surface 101.

In accordance with a primary aspect of the invention, the first main surface 101 and three lateral surfaces 102, 103 and 104 are of a piece with one another and belong to a single cut piece of flexible sheet-like material, shown in Fig. 3, and the conformation of these surfaces together at the at least partial join of the three lateral surfaces 102, 103 and 104 are such by which the shell 10 forms a self- supporting structure.

As already mentioned above, these features of the shell 10 enable a suitcase body to be manufactured that has adequate stability of form and structural rigidity and is at the same time extremely light.

The first main surface 101 preferably has a quadrilateral shape and the three lateral surfaces 102, 103 and 104 comprise a first and a second lateral surface 102, 103 extending at an angle, preferably forming substantially a right angle, from opposing sides of the first main surface 101 , and a third lateral surface 104 extending at an angle, preferably forming substantially a right angle, from a side of the first main surface 101 between said two opposing sides. The third lateral surface 104 is at least partially joined, at its opposing free sides, respectively to free sides of said first and second lateral surfaces 102, 103, adjacent to said third lateral surface 104.

The lateral surfaces 102, 103 preferably have a substantially rectangular shape. Alternatively, to satisfy particular structural or aesthetic requirements during manufacture of the suitcase body 2, the lateral surfaces 102, 103 may also have a substantially trapezoidal or even triangular shape, with one oblique side arranged opposite respective sides of said surfaces that are in common with the first main surface 101.

The lateral surface 104 preferably has a substantially rectangular shape.

These features of the shell 10 are particularly appropriate for manufacturing suitcase bodies of substantially parallelepipedal shape.

In a preferred embodiment of the invention, the shell 10 comprises a second main surface 105, opposed to the first main surface 101 , extending at an angle, preferably forming substantially a right angle, from a free side of the third lateral surface 104 opposed to a side of the lateral surface 104 itself, which is in common with the first main surface 101 , and the second main surface 105 is joined, at its opposing free sides, to portions of free sides, adjacent to said second main surface, of said first and second lateral surfaces 102, 103, respectively.

The second main surface 105 is preferably of a piece with the third lateral surface 104 and therefore forms part of the same cut piece of flexible sheet-like material to which the first main surface 101 and three lateral surfaces 102, 103 and 104 belong.

The presence of the second main surface 105 advantageously increases the structural stability of the shell 10, and in particular of the third lateral surface 104, which in this way is bound to all three surfaces of the shell 10 along the whole of its own perimeter. The structural stability of the lateral surface 104 is particularly important when the shell 10 is used to manufacture a suitcase of the trolley type and such a surface defines a base surface of the trolley, as in the example embodiment shown in Fig. 1. Indeed, in this case it is important to ensure that the planarity of the base surface is maintained, because wheels for pulling the trolley are typically applied to said surface, which wheels must, for correct operation, remain always co-planar during use.

In order to ensure, in every case, a broad area of access to the interior of the suitcase body 2, which is made from the shell 10, the second main surface 105 extends in a substantially perpendicular direction to the third lateral surface 104 preferably over no more than 20%, more preferably over no more than 10%, of the maximum length in the same direction of the first main surface 101 .

The shell 10 preferably comprises openings 106 at at least two of the vertices, and preferably at all of the vertices, formed by the first main surface 101 and by the second main surface 105 with the first and third lateral surfaces 102, 104 and with the second and third lateral surfaces 103, 104, respectively. The openings 106 may advantageously be used for the application of wheels and/or of other bearing members on the base surface of the suitcase body 2, as described in greater detail below.

With a particular choice of shape of the contour of the cut piece from which the shell 10 is formed, which shape is described in greater detail below with reference to Fig. 3, it is possible to see that the openings 106 are defined directly while the shell 10 is being manufactured. In particular, the join between the third lateral surface 104 and, respectively, the first and the second lateral surface 102, 103 at the respective adjacent free sides is preferably made at only a central segment of suitable length of said sides, in such a way as to automatically achieve open regions at the above-mentioned corners on the shell 10.

However, it is not excluded that the openings 106 and any further openings may be made in the shell 10 by means of cutting or perforating subsequent to manufacture of the shell 10 itself.

In addition to flexibility, the material used to make the shell 10 should also present good features of resilience, stability to changes in temperature, workability into sheets, and economicalness. Plastic materials are preferred, for example expanded polyethylene (EPE).

The above-mentioned material preferably has a thickness within the range from about 3 mm to about 5 mm.

In order to satisfy particular aesthetic and/or functional requirements, on to one side of the sheet of flexible material used to manufacture the shell 10 a layer of a compatible, different material may be applied, for example a layer of a different plastic material, or even of skin or fabric.

The fixing of sides of the surfaces of the shell 10 intended to be at least partially joined together as described above may be carried out by means of glueing, welding and/or sewing.

Returning to the trolley 1 shown in Fig. 1 , the first main surface 101 of the shell 10 preferably defines a rear wall 21 (not visible in Fig. 1 ) of the suitcase body 2, the lateral surfaces 102 and 103 of the shell 10 define two opposing lateral walls 22 and 23 (only one of which is visible in Fig. 1 ) of the suitcase body 2, and the lateral surface 104 of the shell 10 defines a bottom wall 24 (not visible in Fig. 1 ) of the suitcase body 2. Furthermore, when present, the second main surface 105 of the shell 10 defines an inferior portion 25a of the front wall of the suitcase body 2. The suitcase body 2 is completed by an upper wall 26 and by a cover 25b for access to the interior space of the trolley 1 , partially or totally defining the front wall of the suitcase body 2.

The upper wall 26 and the cover 25b are preferably formed from respective cut pieces of suitable shape of the same flexible material of which the shell 10 is made. The upper wall 26 is associated with to the shell 2 by fixing by means of glueing, welding and/or sewing by its own free borders opposite the third lateral surface 104 of the shell, defining, as mentioned above, the bottom wall 24 of the suitcase body 2. The cover 25b is openably associated with the shell 10 and with the upper wall 26 at free edges thereof opposite the first main surface 101 of the shell 10, defining, as mentioned above, the rear wall 21 of the suitcase body 2. The cover 25b is preferably associated with the shell 10 and with the upper wall 26 by means of a zip closure 27, schematically represented in Fig. 1 by means of a thicker line, which extends preferably along the whole of the perimeter of the cover 25b.

The suitcase body 2 may furthermore comprise, in a conventional fashion, one or more of external pockets on the front wall, in particular on the cover 25b, the lateral walls 22, 23, and/or the rear wall 21. In the embodiment of the trolley 1 shown in Fig. 1 , a pocket 28 is for example present on the cover 25b. The pocket 28 may be fitted with a zip 29 (schematically represented in Fig. 1 by means of a thicker line) or by other conventional closure means.

The trolley 1 preferably comprises at least two, more preferably four wheels 3 (of which only three are visible in Fig. 1 ) on the bottom wall 24 of the suitcase body 2. The wheels 3 are preferably mounted in the openings 106 predisposed for this purpose in the shell 10 as described above. The wheels 3 may advantageously be of the orientatable type. Fixed bearing members may be provided in place of one or more of the wheels 3 or in addition thereto.

The trolley 1 furthermore comprises retractable pulling means 4 associated with the suitcase body 2. The pulling means are of conventional type and comprise, in the example embodiment shown, a gripping member 41 mounted at the free end of two retractable, possibly telescopic, arms 42. An appropriate place of accommodation (not shown) for fully accommodating the pulling means 4 in retracted configuration is pre-arranged in the suitcase body 2, in particular on the rear wall 21 thereof, in a way known to the person skilled in the field.

The trolley 1 preferably has dimensions such as to be acceptable as hand baggage during transportation by air. In particular, the trolley 1 preferably has dimensions not greater than about 55 cm (height) X about 40 cm (width) X about 25 cm (depth).

Fig. 3 shows a cut piece 200 of flexible sheet-like material shaped for manufacturing the shell 10 described above.

The cut piece 200 is formed from a plurality of fields having a reciprocal shape and position, the shape and position being adapted to permit manufacture of the shell and the pieces being outlined in Fig. 3 by means of dotted lines. It must be borne in mind that such dotted lines are shown for purely illustrative purposes, for better identification of the fields which make up the cut piece 200. In particular, these lines do not necessarily correspond to fold lines in the cut piece 200, these latter possibly being completely absent.

In detail, the cut piece 200 comprises a first main field 201 , preferably quadrilateral in shape, intended to form the first main surface 101 of the shell 10, a first and second lateral field 202, 203 opposed to the first main field 201 , which lateral fields are intended to form respectively opposing lateral surfaces 102 and 103 of the shell 10, and a third lateral field 204 extending from a side of the first main field 201 between said two opposing sides which is intended to form the third lateral surface 104 of the shell 10.

The first and the second lateral field 202, 203 preferably have a substantially rectangular or trapezoidal shape. However, different shapes are not excluded, for example a substantially triangular shape. The third lateral field 204 has a preferably substantially rectangular shape.

Furthermore, the sides of the first main field 201 , of the first lateral field 202 and of the second lateral field which are adjacent to one another and opposed to the third lateral field 204 preferably form a continuous line having a rectilinear or curved, in particular convex, course, as in the example embodiment shown in the drawings. The cut piece 200 preferably also comprises a second main field 205 extending from the free side of the third field 204 opposed to the side of the said lateral field 204 which is in common with the main field 201. The second main field 205 is intended to form the second main surface 105 of the shell 10.

The second main field 205 preferably has a substantially rectangular shape. Also preferably, the side of the second main field 205 which supposed to the side in common with the third lateral field 204 has a concave course. Such a course facilitates the operation of a zip closure which may be applied on such side of the suitcase body 10, as described above.

On the adjacent sides of the first lateral field 202 and of the third lateral field 204, respective projecting flaps 202a and 204a are preferably formed, which flaps are intended to overlap at least partially in the process of forming the shell 0, so as to guarantee an adequate area of contact for joining the first and the third lateral surfaces 101 , 104 of the shell 10.

Analogously, on the adjacent sides of the second lateral field 203 and of the third lateral field 204, respective flaps 203a and 204a' are formed, which flaps are intended to overlap at least partially in the process of forming the shell 10, so as to guarantee an adequate area of contact for joining the second and the third lateral surfaces 103, 104 of the shell 10.

Also preferably, at one end of a side of the first lateral field 202 which is opposed to the side in common with the first lateral field 201 a projecting flap 202b is formed, and on a side of the second main field 205 which is facing towards the first lateral field 202 a corresponding flap 205a is formed. These flaps 202b and 205a are intended to overlap at least partially in the process of forming the shell 10, so as to guarantee an adequate area of contact for joining the first lateral surface 102 with the second main surface 105 of the shell 10.

In an analogous manner, preferably at one end of a side of the second lateral field 203 which is opposed to the side in common with the first main field 201 , a projecting flap 203b is formed, and on a side of the second main field 205 which is facing towards the second lateral field 203 a corresponding flap 205a' is formed. These flaps 203b and 205a' are intended to overlap at least partially in the process of forming the shell 10, so as to guarantee an adequate area of contact for joining the second lateral surface 103 to the second main surface 105 of the shell 10.