COOLING/INTERMODAL CONTAINER, METHOD OF ASSEMBLING A COOLING/INTERMODAL CONTAINER AND EXTRUDER HEAD
20210309451 · 2021-10-07
Inventors
Cpc classification
B29C70/845
PERFORMING OPERATIONS; TRANSPORTING
B29C48/34
PERFORMING OPERATIONS; TRANSPORTING
B65D90/08
PERFORMING OPERATIONS; TRANSPORTING
International classification
B65D90/08
PERFORMING OPERATIONS; TRANSPORTING
B29C48/34
PERFORMING OPERATIONS; TRANSPORTING
Abstract
The invention relates to a cooling container e.g. a refrigerated cargo box of a truck or trailer, a railway container, an intermodal container or a shipping container comprising panels to be connected, having at least one connection between panels (10, 40) comprising a layer of overmoulding material (14), where a panel (10, 40) at least partially is covered on a first side (100) and a second side (200) by the overmoulding material (14). The invention further relates to a method of assembling a cooling container e.g. a refrigerated cargo box of a truck or trailer, a railway container, an intermodal container or a shipping container comprising panels to be connected, where at least one panel (10, 40) is provided with an overmoulding zone (11) comprising a layer of overmoulding material (14) covering at least partially a first side (100) and a second side (200) of the panel (10, 40). The invention also relates to an extruder head for applying a layer of a fluid overmoulding material, a container comprising panels (10, 40) comprising a layer of overmoulding material (14).
Claims
1. A cooling container for a refrigerated cargo box of a truck or trailer, a railway container, an intermodal container or a shipping container comprising panels to be connected, characterized by at least one connection between the panels comprising a layer of overmoulding material, where at least one of the panels is at least partially covered on a first side and a second side by the overmoulding material.
2. A cooling container according to claim 1, where the overmoulding material is a polymer.
3. A cooling container according to claim 1, where the at least one panel is perforated, letting the overmoulding material on the first side of an edge of the at least one panel merge with the overmoulding material on the second side of the edge of the at least one panel.
4. A cooling container according to claim 3, where the at least one panel is perforated in a pattern of elongate holes.
5. A cooling container according to claim 3, where the at least one panel is perforated in a pattern of circular holes.
6. A cooling container according to claim 3 where the at least one panel is perforated by holes arranged in more than one row.
7. A cooling container according to claim 3, where the at least one panel is perforated by holes arranged in a first and a second row, where the second row is displaced in relation to the first row in such a way that a centre or middle of a hole in the second row is placed aligned with a middle distance between holes placed in the first row.
8. A cooling container according to claim 7, where the holes arranged in the second row are displaced in relation to the first and a third row.
9. A cooling container according to claim 1, where the overmoulding material is placed on the at least one panel along an edge of the at least one panel.
10. A cooling container according to claim 1, where at least one of the panels is made of metal.
11. A cooling container according to claim 1, where at least one of the panels is made of a polymer material.
12. A cooling container according to claim 1, where at least one of the panels is made of a composite material.
13. A cooling container according to claim 1, where the at least one connection is a corner connection between a side panel and a roof panel.
14. A method of assembling a cooling container for a refrigerated cargo box of a truck or trailer, a railway container, an intermodal container or a shipping container comprising panels to be connected, characterized in that at least one of the panels is provided with an overmoulding zone comprising a layer of overmoulding material covering at least partially a first side and a second side of the at least one panel.
15. The method according to claim 14, where the overmoulding material flows through holes in the at least one panel during application and is distributed on each side of the at least one panel.
16. The method according to claim 14, where perforations or holes are provided to the overmoulding zone before overmoulding the zone with the overmoulding material.
17. The method according to claim 14, where an inner side panel and a roof panel are joined to a corner profile by gluing or plastic welding.
18. The method according to claim 14, where one of an inner side panel or a roof panel is bended before or after the panels are provided with a layer of overmoulding material to provide parallel and overlapping overmoulding zones before joining the inner side panel and the roof panel by gluing or plastic welding.
19. The method according to claim 14, comprising bending one of an inner side panel or a roof panel providing parallel and overlapping overmoulding zones before joining the inner side panel and the roof panel by overmoulding.
20. An extruder head for applying a layer of a fluid overmoulding material, the extruder head comprising an inlet for supply of overmoulding mass to the extruder head and a chamber for applying overmoulding material to an elongate member, characterised in that the extruder head is provided with an entrance formed to receive a plate or panel on which panel a layer of overmoulding mass is applied, forming a strip of overmoulding material on the panel.
21. An extruder head according to claim 20, where the extruder head is provided with one or more guides for guiding the panel during application of a strip of overmoulding material on the panel.
22. An extruder head according to claim 20, where the strip of overmoulding material is applied around an edge of the panel.
23. An extruder head according to claim 20, where the strip of overmoulding material is applied on a first side of the panel through holes in the panel and forming a strip of overmoulding material on a second side of the panel.
24. An intermodal container, truck or railway waggon comprising a pair of side walls, a ceiling, an end wall, a floor and a door opening, the side walls comprising wall panels and the ceiling comprising roof panels, where the wall panels and/or the roof panels are joined together by the at least one connection according to claim 1.
25. A method of assembling a container by use of the method according to claim 1.
Description
[0062] The above and other features and advantages of the present invention will become readily apparent to those skilled in the art by the following detailed description of exemplary embodiments thereof with reference to the attached drawings, in which:
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[0082] Various embodiments are described hereinafter with reference to the figures. Like reference numerals refer to like elements throughout. Like elements will, thus, not be described in detail with respect to the description of each figure.
[0083] It should also be noted that the figures are only intended to facilitate the description of the embodiments.
[0084] They are not intended as an exhaustive description of the claimed invention or as a limitation on the scope of the claimed invention. In addition, an illustrated embodiment needs not have all the aspects or advantages shown.
[0085] An aspect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiments even if not so illustrated, or if not so explicitly described.
[0086] Throughout, the same reference numerals are used for identical or corresponding parts.
[0087] A cooling container such as a refrigerated cargo box of a truck or trailer, a railway container, an intermodal container or a shipping container 1 shown in
[0088] In a transition between the sidewalls 5 and the roof panel 40 inside the container 1, inner top corner connections 8, 9 are provided.
[0089] In order to avoid riveting in connections between panels and in the inner top corner connections 8, 9 in the container 1, a new solution comprises overmoulding of panels or of parts of an inner top corner connection 8, 9.
[0090] This is achieved by at least one connection between panels 10, 40 comprising a layer of overmoulding material 14, where a panel 10, 40 at least partially is covered on a first side 100 and a second side 200 by the overmoulding material 14.
[0091] The sidewalls 5 are provided with inner side panels 10. The inner side panels 10 are provided with an overmoulding zone 11, which zone is placed along an edge 12 of the side panel 10. In the overmoulding zone 11 of the side panel one or more row of holes 13 is formed. Examples of inner side panels 10 are shown in
[0092] The purpose with the one or more rows of holes 13 is to secure a good attachment of an overmoulding material 14 to the ovemoulding zone 11 of the side panel 10.
[0093] When the panel 10, 40 is perforated, it is possible for the overmoulding material 14 on the first side 100 of an edge 12 of the panel 10, 40 to merge with the overmoulding material 14 on the second side 200 of the edge 12 of the panel 10, 40 through holes 13 of the perforation.
[0094] In
[0095] The feature that the overmoulding material 14 flows through the holes 13 in the inner panel 10 during application and is distributed on each side of the inner panel 10 before it hardens ensures a very good attachment of the overmoulded material 14 to the inner panel 10.
[0096] In a similar way it is possible to provide the roof panel 40 with an overmoulding zone 11, which zone is placed along an edge 12 of the roof panel 40 to be placed adjacent to another roof panel or adjacent to the inner side panels 10. Hereby an overmoulding zone 11 is provided at each side being the first and second side of the roof panel 40, the overmoulding zone pointing towards an inner side panel 10. In the overmoulding zones 11 of the roof panel one or more rows of holes 13 are formed.
[0097] The overmoulding zones 11 of the inner side panels 10 and the roof panel 40 can in an embodiment be joined by a corner profile 15.
[0098] The inner side panels 10 and the roof panel 40 can be metal plates and the holes 13 can be provided by punching, drilling or by other material removing machining processes.
[0099] The corner profile 15 can be made of polymer or another suitable plastic material. The material being used for the corner profile 15 is suitable for bonding with the material used as overmoulding material 14.
[0100] As an example, an overmoulding zone 11 can be placed e.g. 50 mm from an edge of the inner side panel 10 or the roof panel 40. In the overmoulding zone 11, a pattern of perforations is made in shape of two rows of elongate holes. This embodiment is illustrated in
[0101] This zone of perforated plate is overmoulded with an overmoulding material 14 in such a way that in this zone there is overmoulded material 14 on both sides of the plate or panel 10, 40 and the overmoulding material 14 on the two sides is mechanically connected through the perforations or holes 13 in the panels 10, 40 as indicated in
[0102] The solution can also be used to join wall panels 10 to other wall panels 10 and roof panels 40 to other roof panels 40.
[0103] An inner side panel 10 provided with a such overmoulded zone 11 at the edge and another inner side panel 10 provided with a similar overmoulded zone 11 at the edge can be connected by welding the overmoulded zones 11 at the edges together as illustrated in
[0104] In a further embodiment, the overmoulding of two plates being inner side panels 10 may take place at the assembly stage, so the need for separate welding process is eliminated. This is illustrated in
[0105] Here the overmoulding zones 11 of the panels 10 overlaps each other, at least partially.
[0106] The panels mentioned in relation to
[0107] An inner side panel 10 provided with a such overmoulded zone 11 at the edge and a roof panel 40 provided with a similar overmoulded zone 11 at the edge can be connected by welding the overmoulded zones 11 at the edges together as illustrated in
[0108] When using welding as a joining method, the corner profile 15 and the overmoulded material 14 is heated locally, a welding zone is established and the two materials will be joined together forming a weld or a welding seam 16.
[0109] In an embodiment, the overmoulding material 14 is a polymer.
[0110] Welding of polymer-to-polymer can be performed by alternative standard methods for welding polymer. In the above-described embodiments the preparation of parts by overmoulding the edges is separated from a process of assembly of the inner side panel 10 and the roof panel 40, which is an extra welding process at an assembly line. Welding of the polymer parts can be performed by use of resistance welding/fusion welding, where a conductive mesh is placed in between the two polymer parts where melting of the polymer is performed by heating up the mesh by electric current in the mesh.
[0111] Welding can also be carried out by use of other heat sources and by use of additional material or filler material.
[0112] In a further embodiment, the overmoulding of two plates being an inner side panel 10 and a roof panel 40 may take place at the assembly stage, so the need for separate welding process is eliminated. This is illustrated in
[0113] In an embodiment, as shown in
[0114] The inner side panel 10 and the roof panel 40 are connected by welding to the corner profile 15. The welding process in the different embodiments can be carried out by manual welding using a handheld heating source, by a robot or by use of resistance welding/fusion welding, where a conductive mesh is placed in between the two polymer parts being the overmoulding material 14 and the corner profile 15, where melting of the polymer is performed by heating up the mesh by electric current in the mesh placed where the welding seam 16 is to be established.
[0115] In an embodiment the connection between the overmoulding material 14 and the panel 10, 40 can be enhanced by providing a bend 17 to the edge 12 of the panel 10, 40. This bend 17 can be used alone or in combination with the perforations, further enhancing the connection between the overmoulding material 14 and the panels 10, 40.
[0116] Parameters having influence in relation to the strength of the connection is material properties for the panels 10, 40 and the properties for the polymer materials 14.
[0117] Another parameter having influence in relation to the strength of the connection is distribution pattern of holes 13 in the overmoulding zone 11 or perforated zone. A parameter describing a two dimensional view of the perforations 13 can be percentage of area of the panel 4, 10, which is removed when making the holes 13.
[0118] In case the panel 10, 40 is made of metal, an acceptable percentage of removed area will be in a range from 5% up to removed area of 90%, or more typical in the range from 10%-50%. At the lower end of the range, the connection becomes weaker due to a limited cross-sectional area of polymer material 14 caused by low number of holes or perforations 13.
[0119] Another parameter describing the distribution of perforations 13 in a lengthwise direction or row having influence on the strength of the connection, is a relationship α=l/p, where l is a distance between two neighbouring holes 13 of the perforations in a row and p is the period for the perforated pattern, also being a distance between centres of two neighbouring holes 13 in a row.
[0120] A distance between lines going through centres of holes 13 in two neighbouring rows is d. These paremeters is shown in
[0121] It is an aim to adapt the strength of the polymer material 14 in the holes 13 to be balanced with the strength of the perforated panel 10, 40.
[0122] As an example can be mentioned that for a panel 10, 40 made in a high strength material such as High Grade Stainless Steel, the value for a may be relative low as the relative small cross-sectional area of steel needed to outbalance the strength of the significant larger cross-section of the polymer material 14, however for an aluminium panel 10, 40, the value for α need to be 0.5 or higher for the cross-section of aluminium plate material 10, 40 to outbalance the polymer material 14.
[0123] Thickness dimension of the overmoulded polymer 14 is also one factor to consider, the thicker the layer 14 is on the side opposite to the welding 16, the higher strength the connection may have.
[0124] As an example, for panels 10, 40 of material thickness in the range of 0.5 mm to 1.5 mm and with dimensions for the perforated holes 13 in the range of 5 mm to 15 mm, the thickness of the polymer 14 on the side opposite to the welding connection 16 can be in the range of 0.5 mm to 5 mm and more typically 1 mm to 3 mm.
[0125] The strength of the corner connection 8, 9 depends on the material properties for the polymer material chosen and of the size and shape of the perforations 13, being circular holes, polygonal, quadrilateral or rectangular holes or combinations of these shapes of holes 13. Typical suitable polymer materials are polypropylene(PP) and PP blends, however many alternative types of polymer and polymer blends can be chosen for a specific design to fulfil the requirements for strength, visual impression, biocompatibility, regulations for food transport equipment etc. By optimization of the area of the perforations 13, the shapes of the perforations 13 and the properties of the polymer material, the strength of the new corner connection typically exceeds the strength of a comparable rivet based connections by factor of 2 to 5.
[0126] A cooling container e.g. a refrigerated cargo box of a truck or trailer, a railway container, an intermodal container or a shipping container comprising panels to be connected can be assembled according to a method where at least one panel 10, 40 is provided with an overmoulding zone 11 comprising a layer of overmoulding material 14 covering at least partially a first side 100 and a second side 200 of the panel 10, 40.
[0127] In an embodiment of the method the overmoulding material 14 flows through holes 13 in the panel 10, 40 during application and is distributed on each side of the panel 10, 40.
[0128] In an embodiment of the method, perforations or holes 13 are provided to the overmoulding zone 11 before overmoulding the zone 11 with the overmoulding material 14.
[0129] In an embodiment of the method an inner side panel 10 and a roof panel 4 are joined to a corner profile 15 by gluing or plastic welding.
[0130] In an embodiment of the method one of an inner side panel 10 or a roof panel 40 is bended before or after the panels are provided with a layer of overmoulding material 14 to provide parallel and overlapping overmoulding zones 11 before joining the inner side panel 10 and the roof panel 40 by gluing or plastic welding.
[0131] In an embodiment, the method comprises bending one of an inner side panel 10 or a roof panel 40 providing parallel and overlapping overmoulding zones 11 before joining the inner side panel 10 and the roof panel 40 by overmoulding.
[0132] The cost for production of the new corner connection 8, 9 is significantly reduced compared to similar comparable alternative corner connections, as the material costs is reduced by use of polymer only for the connection and as the cost for assembly of the corner connection is reduced. The reduced cost for assembly is much related to the reduced number of parts to be assembled and to the fact that the polymer overmoulding process may be a relative simple direct extrusion process with limited use of labour hours.
[0133] Performing the overmoulding process by direct extrusion of the overmoulding material 14 together with the edge 12 and overmoulding zone 11 of the panel 10, 40 being led through an extrusion crosshead 18.
[0134] Such extruder equipment and extrusion process is standard equipment also typically used for welding polymer parts together. Therefore, only shape of internal flow channels in the extruder head and shape of exit of the extruder head has to be adapted specifically for actual design/shape of the applied overmoulding material 14 (layers of polymer) on to the overmoulding zone 11 of the inner side panel 10. Examples of an extruder crosshead 18 is shown in
[0135] The overmoulding process can be carried out using an extruder head 18 for applying a layer of a fluid overmoulding material to the panel 10, 40, where the extruder head 18 comprises an inlet 20 for supply of overmoulding mass 19 to the extruder head 18 and a chamber for applying overmoulding material 14 to an elongate member, where the extruder head 18 is provided with an entrance formed to receive a plate or panel 10, 40 on which panel 10, 40 a layer of overmoulding mass 19 is applied, forming a strip of overmoulding material 14 on the panel 10, 40.
[0136] In an embodiment, the extruder head 18 is provided with one or more guides 21 for guiding the panel during application of a strip of overmoulding material 14 on the panel 10, 40.
[0137] The guide 21 can be a plane edge on which the edge 12 of the panel 10, 40 can be guided when passing through the extruder head 18. The guide can also be a pair of pins or rollers. The guide can also be adjustable as indicated by an arrow in
[0138] In an embodiment of the extruder head 18, the strip of overmoulding material 14 is applied around an edge 12 of the panel 10, 40.
[0139] When overmoulding the edge 12 of the panel 10, 40, one or more guides 21 is placed before the panel 10, 40 reaches the entrance of the extruder head 18. Another guide (not shown) can be placed along a moving path of the panel 10, 40 in a suitable distance from the outlet of the extruder head 18 so the strip or edge of overmoulded material 14 is cooled down enough to let the overmoulded material 14 cure sufficiently not to let the guide scrape off the overmoulded material 14 from the panel 10, 40.
[0140] In this embodiment, the guide 21 can be used to determine the thickness of the overmoulded material 14 provided to the edge 12 of the panel 10, 40.
[0141] In an embodiment of the extruder head 18 the strip of overmoulding material 14 is applied on a first side 100 of the panel 10, 40 through holes 13 in the panel 10, 40 and forming a strip of overmoulding material 14 on a second side 200 of the panel 10, 40.
[0142] When applying the overmoulding material 14 to the inner side panel 10 using the extruder head 18 the edge 12 and the overmoulding zone 11 of the panel 10 is introduced into the head 18 and an overmoulding mass 19 is filled into the extruder head 18 via an inlet 20. Hereafter the overmoulding mass 19 leaves the extruder head 18 through an outlet together with the panel 10 forming the strip of overmoulding material 14. When the material for overmoulding enters the extruder head 18 in fluid condition it flows through the holes 13 in the panel 10 and adheres to both sides 100, 200 of the panel 10. The same apply if the panel is a roof panel 40 or if the panel is an outer panel.
[0143] Overmoulding a zone 11 or a part of a panel 10, 40 with a layer of polymer 14 on the two sides 100, 200 as well as in the holes 13 of the panel 10, 40 forms a mechanical connection between the strip of polymer material 14 and the panel 10, 40. Hereby the inner side panel 10 and the roof panel 40, even if they are metal plates, can be connected mechanically by welding together the two strips of polymer 14. The two polymer strips 14 can be directly welded together or an extra polymer component/an extra polymer profile can be interconnected between the two polymer strips. An extra polymer profile can be a corner profile 15.
[0144] The inner side panel 10 and the roof panel 40 can also be made of polymer plates or composite plates, however the possible ranges for strength and dimensions and shapes of perforations 13 need to be adapted to the actual type of material and thickness of plates.
[0145] The function of the assembly is to mechanically connect the edges 12 of two plates being the inner panels 10, 40 of a container 1 to each other, this mechanical connection having the needed strength and at same time the needed tightness and being hygienic optimal. Hereby the panels 10, 40 are mechanically connected to each other and at the same time, the connection is tight, meaning that there is no need for an additional seal or gasket.
[0146] The solution is also achieved by an intermodal container, truck or railway waggon comprising a pair of side walls, a ceiling, a floor, an end wall and a door opening, the side walls comprising wall panels and the ceiling comprising roof panels, where the wall panels 10 and/or the roof panels 40 are joined together by a connection according to embodiments mentioned above.
[0147] The solution is also achieved by a method of assembling a container by use of the method according to one or more embodiments mentioned above.
[0148] The uniqueness of the polymer based corner connection 8, 9 is that the welded polymer brings high degree of tightness and a smooth surface, which is easy to clean and is hygienic, and at same time the relative limited thickness of the overmoulded polymer strip 14 brings strength and toughness needed for the corner connection 8, 9.
[0149] Regarding tightness, the performance of the connection depends among other things on the type of polymer chosen, as soft polymer will tend to tighten better against the panels than hard polymer.
[0150] Various types of adhesive polymers, either with additional gluing components such as variants of Thermo Plastic Elastomers (TPE) or with additional additives for vulcanizing to the surface of the plates such as Thermo Plastic Vulcanize (TPV) can be used.