PROTECTIVE CONTAINER FOR THE STORAGE AND/OR TRANSPORT OF FRAGILE OBJECTS AND MANUFACTURING METHOD

Abstract

A container for objects comprises an outer casing with walls defining an internal volume and padding inserted into the internal volume of the casing. The outer casing is made of thermoformed plastic material, and the padding consists of a shaped foam shell, of a shape and size adapted to the shape and size of the internal volume of the casing. A method of manufacturing the object container comprises: providing at least one sheet of a thermoformable plastic material; thermoforming the at least one sheet of thermoformable plastic material to form an outer casing of the container; forming a padding consisting of a shaped foam shell, of a shape and size adapted to the shape and size of an internal volume of the outer casing of the container; inserting the padding into the internal space of the outer casing of the container.

Claims

1. A container for objects, comprising: an outer casing with walls defining an inner volume; a padding inserted in the inner volume of the casing, wherein said outer casing is made of thermoformed plastic material, and said padding consists of a shaped foam shell, with a shape and dimensions adapted to the shape and dimensions of the inner volume of the casing.

2. A method of manufacturing a container for objects, comprising: providing at least one sheet of a thermoformable plastic material; thermoforming the at least one sheet of thermoformable plastic material to create an outer casing of the container; forming a padding consisting of a shaped foam shell, with a shape and dimensions adapted to the shape and dimensions of an inner volume of the outer casing of the container; inserting the padding into the inner space of the outer casing of the container.

3. The container or the method of manufacturing a container according to claim 1, wherein the material of the outer casing of the container is a thermoplastic polymer selected from: acrylonitrile-butadiene-styrene, polystyrene, polycarbonate, polyethylene terephthalate glycol.

4. The container or the method of manufacturing a container according to claim 1, wherein said foam shell is made of polyurethane rubber.

5. The container or the method of manufacturing a container according to claim 1, wherein said outer casing comprises a first casing part and a second casing part coupled or which can be coupled to each other, each of said first casing part and second casing part being made of thermoformed plastic material.

6. The container or the method of manufacturing a container according to claim 5, wherein the first casing part and/or the second casing part comprise respective ribs at least on a respective wall of dimensions prevailing in relation to the other respective walls.

7. The container or the method of manufacturing a container according to claim 5, comprising hinge means mounted to said first and second casing parts for the hinged coupling of the first and second casing parts.

8. The container or the method of manufacturing a container according to claim 7, wherein the hinge means comprise at least one lid-holding hinge.

9. The container or the method of manufacturing a container according to claim 8, wherein the hinge means comprise a flat hinge.

10. The container or the method of manufacturing a container according to claim 5, wherein said padding comprises a first foam shell, of shape and dimensions adapted to the shape and dimensions of an inner volume of the first portion of casing, and a second foam shell, of shape and dimensions adapted to the shape and dimensions of an inner volume of the first portion of casing.

11. The container or the method of manufacturing a container according to claim 1, comprising corners, preferably made of metal, applied to respective edges of the casing.

12. The container or the method of manufacturing a container according to claim 5, comprising closing means mounted on the first and second part of the casing operable to ensure maintenance of the casing in a closed condition.

13. The container or the method of manufacturing a container according to claim 1, comprising gripping means by a user.

14. The container or the method of manufacturing a container according to claim 13, wherein said gripping means comprises a handle.

15. The container or the method of manufacturing a container according to claim 1, wherein the casing and the padding comprise respective visual inspection means to allow a visual inspection of the inside of the container without the need to open it.

16. The container or the method of manufacturing a container according to claim 10, wherein the first and/or second foam shell comprises a protective film comprising a blend of Polystyrene or any petroleum-based polymer produced through the polymerization of styrene monomers and polyethylene or any other thermoplastic polymer obtained from the polymerization of ethylene.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0041] Features and advantages of the present invention will be clearer from the following detailed description of its possible embodiments, provided by way of example and not limitation, to be read with reference to the attached drawings in which:

[0042] FIG. 1 shows, in lateral-front perspective view, a container in accordance with an exemplary embodiment of the present invention, in open condition;

[0043] FIG. 1.1 is a cross-section of a first foam shell with a protection film according to embodiments of the invention;

[0044] FIG. 2 shows, in perspective view from behind, the container of FIG. 1;

[0045] FIGS. 3A and 3B show, in a lateral-front perspective view and, respectively, in a rear angular perspective view, the container of the previous figures, in closed condition;

[0046] FIG. 4 shows, in front perspective view, an outer casing or body of the container of the previous figures, in open condition;

[0047] FIG. 5 shows, in perspective view, two parts of an internal padding for the outer casing of FIG. 4;

[0048] FIGS. 6A and 6B show a first part of the two internal padding parts of FIG. 5, in angular perspective from above and below respectively;

[0049] FIGS. 7A and 7B show a second part of the two internal padding parts of FIG. 5, in angular perspective from above and below respectively.

DETAILED DESCRIPTION OF EMBODIMENTS

[0050] A container according to an exemplary and non-limiting embodiment of the present invention is shown in the figures.

[0051] The container according to the embodiment shown and which will be described by way of a non-limiting example, indicated in its entirety with the reference 100, is similar to a suitcase or briefcase.

[0052] The container 100 has the shape of a parallelepiped, in particular a rectangular parallelepiped. In embodiments, the edges (corners and vertices) of the container 100 are rounded.

[0053] The container 100 comprises an outer casing 101, which defines a body of the container 100. The walls of the outer casing 101 delimit an inner space or volume of the container 100.

[0054] The outer casing, or body, 101 of the container 100 comprises two casing parts or body parts. The two parts of casing 101 comprise a first casing part 103 and a second casing part 105.

[0055] The first and second casing parts 103, 105 are coupled or can be coupled with each other.

[0056] One of the two parts of the casing 101, for example the first casing part 103, can be intended to constitute a bottom of the container 100, and the other part of the casing 101, for example the second casing part 105, can be intended to constitute a lid of the container 100. The first and second casing parts 103,105 are comparable to two half-shells which, when coupled, define a shell.

[0057] In the exemplary case of a container of parallelepiped shape, in particular a rectangular parallelepiped, such as the container 100 of the example described herein, the two casing parts, first 103 (bottom of the container 100) and second 105 (lid of the container 100) each have the shape of a hollowed parallelepiped.

[0058] The first casing part 103 (bottom of the container 100) comprises a bottom wall 107, generically quadrangular (rectangular or square), surrounded by four perimeter walls which rise from the bottom wall 107 substantially perpendicular to it and which, with the bottom wall 107, delimit an inner volume of the first casing part 103. The four perimeter walls comprise a front wall 109, along a first longitudinal side of the bottom wall 107, a rear wall 111, along a second longitudinal side of the bottom wall 107 opposite the first longitudinal side, and two lateral walls 113, which join the front 109 and rear 111 walls running along opposite transverse sides of the bottom wall 107.

[0059] The second casing part 105 (lid of the container 100) comprises a top wall 115, generally quadrangular (rectangular or square), surrounded by four perimeter walls which extend from the top wall 115 substantially perpendicular to it and which, with the top wall 115, delimit an internal volume of the second casing part 105. The four perimeter walls comprise a front wall 117, along a first longitudinal side of the top wall 115, a rear wall 119, along a second longitudinal side of the top wall 115 opposite the first longitudinal side, and two lateral walls 121, which join the front 117 and rear 119 walls running along opposite transverse sides of the top wall 115.

[0060] The first casing part 103 and the second casing part 105 can be coupled together at their respective open side (opposite to the bottom wall 107 of the first casing part 103 and to the top wall 115 of the second casing part 105), to obtain a single casing divided into two parts (for example, substantially in half).

[0061] When the first casing part 103 and the second casing part 105 are coupled, the respective bottom wall 107, top wall 115 and perimeter walls 109, 111, 113, 117, 119, 121 delimit a respective portion of the inner volume of the container 100.

[0062] The coupling between the first casing part 103 and the second casing part 105 of the container 100 is such as to make it possible to open the outer casing 101 to allow access to the inner volume of the container 100.

[0063] In embodiments of the present invention, the first casing part 103 and the second casing part 105 can be of substantially equal dimensions to each other, in particular they can have equal heights, so that the inner volume portions of the container 100 delimited by the walls of one and the other of the first casing part 103 and the second casing part 105 are substantially equal to each other. Alternatively, in embodiments of the present invention, the first casing part 103 and the second casing part 105 can be of different dimensions from each other, in particular they can have different heights; for example, the part of the casing (first casing part 103 in the example) intended to constitute the bottom of the container 100 can have a greater height than the part of the casing (second casing part 105 in the example) intended to constitute the lid of the container 100. The sizing of the first and second casing parts depends, for example, on the nature of the objects that the container 100 is intended to contain.

[0064] The outer casing 101 of the container 100, in the example considered the first casing part 103 and the second casing part 105, is advantageously made of thermoplastic material. The thermoplastic material can be or comprise for example a thermoplastic polymer selected from: ABS (acrylonitrile-butadiene-styrene), polystyrene, polycarbonate, PETG (polyethylene terephthalate glycol). Other known thermoplastic polymers can be used to create the outer casing 101 of the container 100. The choice of the particular thermoplastic polymer to be used can depend on the specific intended use of the container 100. The first casing part 103 and the second casing part 105 are thermoformed pieces in the chosen thermoplastic material.

[0065] In other embodiments, the outer casing 101 of the container 100 can be made, at least partially, of aluminum or an alloy of aluminum.

[0066] The thickness of the walls of the outer casing 101 of the container 100 can for example vary between 1 mm and 10 mm; different thicknesses of the walls of the outer casing 101 (in the example, the walls 107, 115, 109, 111, 113, 117, 119, 121 of the first casing part 103 and of the second casing part 105) are possible, depending on the intended use of container 100.

[0067] The first casing part 103 and the second casing part 105, can be coupled together by hinging at their respective perimeter edges. For example, as shown in the figures, one or more, preferably two lid-holding hinges 125 are mounted in correspondence with the rear wall 111 of the first casing part 103 (bottom of the container 100) and the rear wall 119 of the second casing part 105 (lid of the container). The lid-holding hinges 125 can be fixed, for example with screws and nuts, to the rear walls 111 of the first casing part 103 and 119 of the second casing part 105 of the container 100. In embodiments, in the rear walls 111 of the first casing part 103 and 119 of the second casing part 105 of the container 100, respective recesses configured to accommodate the lid-holding hinges 125 are obtained (for instance by thermoforming the thermoplastic material), so that the latter, once mounted on the first 103 and second 105 parts of the casing, are substantially recessed into the thickness of the rear walls 111 and 119 and substantially level with the outer surface of the rear walls 111 and 119 themselves.

[0068] In embodiments, the lid-holding hinges 125 are configured to allow mutual rotation of the first casing part 103 and the second casing part 105 by an angle between 90 and 180 (with respect to a closing position of the container 100), for instance an angle of approximately 90, and the maintenance of the first casing part 103 and the second casing part 105 in the rotated position; in this way, once the second casing part 105 (lid of the container 100) has been rotated to open the container 100 and make its interior accessible, the second casing part 105, the lid 115, is kept in the container 100 opening position, for example at 90 with respect to the first casing part 103 (bottom of the container 100), without the need for the user to keep the lid of the container 100 in this position, and without having to remove or overturn it completely (rotating the second casing part 105 by 180 with respect to the first casing part 103) on a support plane (for example the plane on which the bottom of the container 100 is placed).

[0069] In embodiments, the lid-holding hinges 125 are positioned relatively close to the ends of the rear walls 111 and 119 of the first 103 and second 105 casing parts, close to the rear edges of the container 100.

[0070] In embodiments, a flat hinge 127 is mounted to the rear walls 111 and 119 of the first casing part 103 and the second casing part 105, between the lid-holding hinges 125, for example by means of rivets. The flat hinge 127 has a reinforcing function and allows easy and homogeneous opening of the container 100, preventing any twisting.

[0071] On the perimeter edge of the front walls 109 and 117, side walls 113 and 121 and rear walls 111 and 119 of the first and second casing parts 103 and 105, coatings are preferably applied comprising profiles 129 shaped with self-centering interlocking (or reversible profile), preferably in aluminum, which in addition to performing protection functions for the user, allow the two casing parts 103 and 105 to fit together perfectly when closed on each other, at the same time giving stability to the entire container 100, protection from external agents, structural robustness to the entire assembly.

[0072] In embodiments, at the corners between the walls 109 and 113, 113 and 111, 117 and 121, 121 and 119, corner inserts 131, for example made of aluminum, are provided to join the sides of the covering profiles 129 and to make to prevent the covering profiles 129 from being stripped when using the container 100 and to improve the aesthetic appearance of the junction of the two casing parts 103 and 105.

[0073] In embodiments, the container 100 is equipped with structural reinforcing elements.

[0074] In particular, the reinforcing elements can comprise formed ribs (by thermoforming the thermoplastic material) in at least one of, preferably in both, the first casing part103 and second casing part105.

[0075] In particular, by way of example and with reference to the container 100 of the embodiment considered here, raised elements can be provided in the two casing parts 103 and 105, for example one or more longitudinal ribs 133 and/or one or more transverse ribs 135 in the bottom wall 107 of the first casing part 103 and/or in the top wall 115 of the second casing part 105.

[0076] The ribs contribute to stiffening and strengthening the structure of the container 100, in particular against torsion and overlapping. The number and/or arrangement of the transverse ribs 133 and/or longitudinal 135 can depend on the dimensions of the container 100 and its intended use.

[0077] The edges of the container 100 are the areas of the container 100 that are generally more fragile and more stressed in the event of a collision.

[0078] In embodiments of the present invention, the reinforcing elements can comprise corners placed in correspondence with one or more edges of the outer casing 101 of the container 100, to make the edges themselves more resistant. For example, corners 137 can be provided in correspondence with one or more, preferably all the edges of the first casing part 103 (bottom of the container 100), and/or corners 139 in correspondence with one or more, preferably all the edges of the second casing part 105 (lid of the container 100).

[0079] In embodiments, the corners 137 and 139 are elements made of metal, for example aluminum, so as not to significantly weigh down the container 100. The corners can be mounted to the respective casing parts 103 and 105 by means of suitable fixing means, for example glue or rivets.

[0080] In embodiments, the corners 137 and 139 are substantially recessed into the thickness of the casing parts 103 and 105 to which they are mounted, so that the corners 137 and 139 are substantially level with the external surfaces of the two casing parts 103 and 105, protruding from them at most by 1 mm or less, so as not to be dangerous for the user when handling the container 100. To this end, in the two casing parts 103 and 105 respective recesses are obtained (by forming the thermoplastic material) at their edges, configured to accommodate the corners 137 and 139.

[0081] On the front side of the container 100, closing means are provided for the container 100 itself. The closing means may comprise one or more, two in the example considered, closures 141, mounted on the front walls 109 and 117 of the first and second casing parts 103 and 105. The closures 141 are for example of the self-releasing lever type, although the type of closure that can be adopted is not restrictive. The closures 141 are operable to ensure that the container 100 remains closed. The closures 141 can also be equipped with respective locks.

[0082] In embodiments, the front walls 109 and 117 of the first and second casing parts 103 and 105 are shaped so as to have niches intended to house the closures 141, so that the latter, when mounted on the casing 101, are substantially level with the external surface of the casing 101.

[0083] In embodiments, for added strength, the closures 141 are mounted to the front walls 109 and 117 of the first and second casing parts 103 and 105 using screws.

[0084] To make transportation easier, the container is advantageously equipped with gripping means by a user. In the exemplary container 100 described and shown, the gripping means comprises a handle 143 on the front side of the container 100. In embodiments, the handle 143 is applied to the front wall 109 of the first casing part 103. In embodiments, the handle 143 is rotatable around a rotation axis parallel to the front wall 109 of the first casing part 103.

[0085] In embodiments, the container 100 is equipped with feet for placing the container 100 on a support surface, also useful for stacking the container 100 on other similar or different containers.

[0086] The stacking feet can comprise first feet 145 for resting the first casing part 103 on a support surface; the first feet, preferably four in number, are applied externally to the bottom wall 107 at the four vertices thereof.

[0087] The stacking feet can also comprise second feet 147 for placing the container 100 vertically. The second feet, preferably four in number, are applied externally to the rear walls 111 and 119 of the first and second casing parts, two to the rear wall 111 of the first casing part 103 and two to the rear wall 119 of the second casing part 105.

[0088] For example, stacking feet can be mounted to the corners of the container 100.

[0089] The stacking feet can protrude from the body of the container (male feet, such as the first and second feet 145 and 147 of the container 100 of the example considered). For stacking the containers on top of each other and to maintain the stability of the stack of containers, it is also possible to provide feet that retract into the body of the container (female feet), externally to the top wall 115 of the second casing part 105.

[0090] The stacking feet can be made with various compounds and in various sizes, so as to respect and not affect the features of the case as a whole.

[0091] The container may be equipped with visual inspection means of its contents. In the container 100 of the example considered, the visual inspection means include an inspection window 149, comprising an opening in the top wall 115 of the second casing part 105, closed by a sheet of substantially transparent material, for example plexiglass or other suitable material. This can be advantageous as it allows the user to be able to recognize at a glance whether the container houses an object and what object is contained in the container, without having to open it, so as not to run the risk of contaminating the contents. The inspection window can be in a central position of the top wall 115.

[0092] For the internal padding of the container 100, inside each of the first casing part 103 and second casing part 105, a respective first foam shell 151 and second foam shell 153 are inserted, specifically shaped so as to be adapted to the shape and dimensions of the respective first casing part 103 and second casing part 105. The first and second foam shells 151 and 153, are shaped so as to be, on their side intended to adhere to the respective first part 103 and second part 105 of the casing, shaped in a manner complementary to the shape of the surface internal part of this respective part of the casing (for example so as to have ribbing 155 and 157 respectively complementary to the ribs 133 and 135), and, on their opposite side, so as to define seats with a shape and dimensions complementary to the object that the container 100 is intended to contain, so that the object that will be inserted into the container is completely wrapped and protected.

[0093] In embodiments, the first and/or second foam shell 151, 153 can comprise a protective film 152, 154, shown in FIGS. 1 and 1.1.

[0094] The protective film could comprise a blend of a petroleum-based polymer produced through the polymerization of styrene monomers, for instance Polystyrene (PS), and a thermoplastic polymer obtained from the polymerization of ethylene, for instance polyethylene (PE). The blend has a chemical and mechanical resistance higher than standard Polystyrene.

[0095] According to embodiments, the material of the protective film has permanent dissipative properties and is able to protect electronic devices against static electricity.

[0096] According to embodiments, the protective film can have a thickness of 1 to 8 mm.

[0097] Some properties of the material of the protective film are indicated in Table 1.

TABLE-US-00001 TABLE 1 PROPERTY TEST METHOD UNIT VALUE Density ISO 1183-1 gr/10 min 1.5 Determination of the ISO 1133 gr/10 min 6 fluidity index (200 C./5 KG) Determination of Vicat ISO 306 (MET A) C. 99 softening temperature Determination of tensile ISO 527 Mpa 20 properties (tensile stress) Determination of tensile ISO 527 % 80 properties (tensile strain) Tensile Modulus ISO 527 Mpa 1200 Determination of Izod ISO 180/1A KJ/m2 21 impact strength (23 C.) Determination of Izod ISO 180/1A KJ/m2 10 impact strength (30 C.) Fire reaction index UL 94 Class HB (3.00 MM) Surface electrical ANSI20-20/ESD Ohm/sq 10 ELV 8- resistivity measurement STM11.11 10 ELV (Rs) 9 Determination of Shore ISO 868 D 65 hardness

[0098] According to embodiments, the protective film 152, 154 adheres to the respective foam shell. In embodiments, glue or the like can be interposed between the film and the foam shell material.

[0099] In other embodiments, the protective film 152, 154 can be provided on the first foam shell and/or on the second foam shell in a molding step (co-molding). For instance, the first and/or second foam shells can be made by injection molding, and the film can be provided during such molding.

[0100] In other embodiments, the film can be provided in sheet form and properly shaped during the mold forming step of the first and/or second foam shells. The adherence between the film and the first and/or second foam shells can be obtained by high temperature in the molds.

[0101] The first and second cell foams can be made of VORALUX HM 682 Polyol and SPECFLEX NE 286 Isocyanate by DOW. As it is known, VORALUX HM 682 Polyol and SPECFLEX NE 286 Isocyanate is a cold cure TDI based system specially suited to mold flexible foams for furniture market with molded density between 40-80 Kg/m.sup.3.

[0102] In the foam shell 153 to be inserted in the second casing part 105, an inspection opening 159 can be provided in correspondence with the inspection window 149; both the inspection opening 159 and the inspection window 149 are located in correspondence with an area 161 of the first foam shell 151 intended to house the object that must be contained in the container 100.

[0103] In particular, the first and second foam shells 151 and 153 are made of polyurethane rubber with various compounds depending on the needs of the project. The choice of the particular compound, in particular its characteristics of softness, antistaticity, capacity and weight of the contents, resistance to tears, etc., may depend on the intended use of the container.

[0104] For the manufacture of the container 100, each of the two thermo-formed pieces constituting the first casing part 103 (bottom of the container 100) and the second casing part 105 (lid of the container 100) of the casing 101 of the container 100 is made individually and separately by thermoforming.

[0105] As is known, thermoforming is a technique for hot molding of plastic materials, starting from heated sheets or films, under pressure or vacuum.

[0106] In thermoforming, a mold is first made defining the shape of the piece to be made, then a sheet of the chosen thermoplastic material is heated in an oven at a certain temperature such as to make it flexible, malleable, so as to be able to give it the desired shape when the heated sheet is placed in the mold with the application of vacuum, and takes on the desired shape. After cooling, the semi-finished piece thus obtained is then cut to eliminate residues.

[0107] If the inspection window 149 is to be provided in the second casing part 105, the sheet of substantially transparent material is applied to the relevant opening in the top wall 105.

[0108] The components described previously are applied to the two casing parts 103 and 105 thus formed (for example the reversible profiles, the corner inserts, the corners, the first and second feet, the handle, the closures) and the two casing parts are then hinged by assembling the lid-holding hinges and the flat hinge.

[0109] Subsequently or in parallel, the internal padding of the container is made, in particular the two foam shell first 151 and second 153 are made individually and separately.

[0110] As is known to those skilled in the art, the manufacturing of a foam shell for padding essentially comprises the following steps.

[0111] Two molds are created which define the desired shapes of the two shells 151 and 153 that aredesired. The compound and a release agent is inserted into the molds, the function of which is to prevent the foam from adhering to the walls of the molds.

[0112] Once the appropriate foam has been chosen, its components (for example, a resin and a catalyst) are mixed.

[0113] The mixed foam thus obtained is poured into the previously prepared molds, filling them.

[0114] The foam is then allowed to harden, to form the foam shell.

[0115] Once the foam has hardened, the foam shells are removed from the molds.

[0116] This is followed by a finishing phase, in which any excess foam is eliminated from the foam shells obtained, and possibly a sanding phase of the surfaces of the foam shells, to obtain smooth surfaces.

[0117] Non-limiting examples of materials that can be used to create the outer casing 101 of the container 100 and the internal padding are shown below.

[0118] A suitable thermoplastic material for the production, by thermoforming, of the outer casing 101 of the container 100 is conductive polystyrene from the Universal Polythex company.

[0119] A suitable foam for the creation of the two foam shells of the internal padding of the container 100 is the product called Elastfoam 14112/128 mod. 2 of the BASF company.

[0120] Various modifications to the previously described embodiments are possible, as are other embodiments of the present invention. In particular, the present invention, thanks to the great flexibility offered by the thermoforming techniques of thermoplastic materials and the creation of foam shells, leads itself to the creation of containers of the most disparate shapes and materials, depending on their final use, therefore the example of a container similar to a briefcase described and shown in the figures is not at all restrictive.

REFERENCE LEGEND IN THE FIGURES

[0121] 100 Container [0122] 101 Outer casing (casing) [0123] 103 First casing part [0124] 105 Second casing part [0125] 107 Bottom wall (first casing part) [0126] 109 Front wall (first casing part) [0127] 111 Rear wall (first casing part) [0128] 113 Side walls (first casing part) [0129] 115 Top wall (second casing part) [0130] 117 Front wall (second casing part) [0131] 119 Rear wall (second casing part) [0132] 121 Side walls (second casing part) [0133] 125 Lid-holding hinges [0134] 127 Flat hinge [0135] 129 Reversible profile [0136] 131 Corner inserts for reversible profile [0137] 133 Longitudinal ribs [0138] 135 Transverse ribs [0139] 137 Corners (first casing part) [0140] 139 Corners (second casing part) [0141] 141 Closures [0142] 143 Handle [0143] 145 First feet [0144] 147 Second feet [0145] 149 Inspection window [0146] 151 First foam shell [0147] 152 Protective film of the first foam shell [0148] 153 Second foam shell [0149] 154 Protective film of the second foam shell [0150] 155 Ribbing [0151] 157 Ribbing [0152] 159 Inspection opening