Improved connection for a vehicle frame of a public transport vehicle

Abstract

Chassis (1) for a public transport vehicle extending along a longitudinal axis (A), comprising a plurality of elements (E) connected together via a connecting system (10, 20), such elements (E) being made of different materials. [Fig. 3] Figure 3

Description

Title of the invention: Improved connection for a vehicle frame of a public transport vehicle. Technical field

[0001] The present innovation relates to an improved connection for a vehicle frame.

[0002] The present innovation finds its preferred, though not exclusive, application in public transport vehicles such as buses. Reference is made to this application by means of the example below. Context of innovation

[0003] Public transport vehicles, such as buses, and vehicles in general, are provided with a frame / chassis which defines one of the structural parts of the vehicle.

[0004] The vehicle body and certain functional systems are fixed to such a frame.

[0005] In order to provide sufficient strength, the bus chassis is made of steel bars that are welded together to define a lattice structure that shapes the frame. Such a frame usually defines a roof and a pair of side walls. Optionally, part of the floor may also be defined by the frame.

[0006] Welding between the bars clearly provides a strong and fixed connection between them. However, welding also entails certain disadvantages.

[0007] First, welding can only be carried out between the same or similar materials. Indeed, welding between different metals such as steel or aluminum is difficult or only tolerated using very special techniques and alloys that exponentially increase manufacturing costs.

[0008] Secondly, welding is a complex and time-consuming operation, and at least a minimum thickness of the parts to be welded is necessary to reduce the risk of thermal deformation and to allow for welding. This required thickness is, however, oversized relative to the structural needs of the frame, thus increasing the weight, cost, and fuel consumption of the vehicle.

[0009] Thirdly, it is well known that the welded joint area is more susceptible to corrosion, such as rust, and consequently to the formation of cracks that can lead to damage. Therefore, constant maintenance is necessary, and special operations such as cataphoresis are required after welding.

[0010] Therefore, the existing frame, in order to allow access for welding and in order to reduce the welding material, has a shape, as illustrated in Figures 1 and 2, which describes a frame 1' of the prior art.

[0011] Such a frame 1' comprises a roof 2' and a pair of side walls 3' extending perpendicularly to the roof 2'. Both the roof 2' and the walls 3' are made via a lattice structure defined by a plurality of elements 4'. With reference to [Fig. 2], the roof 2' is made via a pair of longitudinal elements 5' made substantially as single pieces all extending along the longitudinal axis A' of the frame 1'.

[0012] Such a pair of longitudinal elements 5' is connected in a transverse direction with respect to the longitudinal axis A' by a plurality of transverse bars 6' spaced along the longitudinal axis A' and by a plurality of inclined bars 7' passing through the longitudinal elements 5' and the transverse bars 6'. In particular, the inclined bars 7' are positioned to define a plurality of rhombuses along the direction of the axis A'. Other connecting elements 8' are placed between the inclined bars 7' and the longitudinal elements 5' to reinforce the overall structure.

[0013] Clearly, the above structure proves to be heavy and complex but allows the use of the welding technique between the different elements of the frame 1'.

[0014] In addition to what is presented above, the energy / gasoline required for the welding operation for the elements composing a frame defining a roof of a public transport vehicle is not negligible in the overall manufacturing cost for the production of the vehicle.

[0015] In view of the above, there is a need to propose a frame which has the same structural properties as existing frames without the disadvantages related to the welding technique.

[0016] One aim of the present innovation is to satisfy the above-mentioned needs in a cost-effective and optimized manner. Summary of the innovation

[0017] The above-mentioned purpose is achieved by a frame 1 for a public transport vehicle extending along a longitudinal axis A, comprising a plurality of elements E connected together via a connection system 10, 20, said elements E being made of different materials, in which said frame 1 comprises: a pair of longitudinal lateral elements 2 extending parallel to said longitudinal axis A, said longitudinal lateral elements 2 being made by connecting together, via said connecting system 10, 20, a plurality of elements E; a plurality of transverse bars 3 extending transversely to said longitudinal axis A, said transverse bars 3 being made by connecting together, via said connecting system 10, 20, a plurality of elements E; a plurality of inclined bars 5, 6 connected, in an operational manner, between at least one of said cross bars 3, said longitudinal lateral elements 2 and said internal longitudinal bar 4, in which said inclined bars 5, 6 are made by a single element E connected, at the level of its ends, to at least one of said cross bars 3, said longitudinal lateral elements 2 and said internal longitudinal bar 4.

[0018] In detail, said materials include metals and plastic / polymers and preferably include different metals and different plastics / polymers.

[0019] Furthermore, the frame 1 may include an internal longitudinal bar 4 extending parallel to said longitudinal axis A and is transversely included between said longitudinal lateral elements 2, said internal longitudinal bar 4 being made by connecting together, via said connecting system 10, 20, a plurality of elements E.

[0020] In particular, said inclined bars 5, 6 are arranged relative to each other in order to define rhombuses along said longitudinal axis A.

[0021] Furthermore, said connection system 10, 20 includes at least one mask 10', 20' comprising at least one first wall 10a and a second wall 10b configured to be fixed to said at least one pair of elements E in order to fix the latter together.

[0022] In detail, said at least one mask 10', 20' is connected to said element E via fastening means 11 or by gluing.

[0023] The innovation also relates to a vehicle comprising a frame 1, as summarized above. Brief description of the drawings

[0024] For a better understanding of the present innovation, a preferred embodiment is described in the following section, by means of a non-limiting example, with reference to the accompanying drawings, in which:

[0025] [Fig.1] Fig.1 is a schematic perspective view of a bus frame, as known in the art;

[0026] [Fig.2] The [Fig.2] is a schematic top view of a bus frame, as known in the art;

[0027] [Fig.3] The [Fig.3] is a schematic top view of a bus frame, according to the innovation;

[0028] [Fig.4] The [Fig.4] is a schematic exploded perspective view of a part of the bus frame, including a coupling according to a first embodiment of the innovation;

[0029] [Fig.5] The [Fig.5] is a schematic perspective view of another part of the bus frame, comprising a coupling according to a first embodiment of the innovation;

[0030] [Fig.6] The [Fig.6] is a schematic exploded view of a part of the bus frame comprising a coupling according to a second embodiment of the innovation;

[0031] [Fig.7] Fig.7 is a schematic perspective view of another part of the bus frame comprising a coupling according to a second embodiment of the innovation; and

[0032] [Fig.8] [Fig.9] [Fig. 10] Figures 8 to 10 are perspective views of examples of coupling elements according to the first and second modes of embodiment of the innovation. Detailed description of the innovation

[0033] The [Fig.3] describes a frame 1 comprising a plurality of elements E connected in a reticular manner via a connection system 10, 20 according to the innovation and as further described in more detail.

[0034] Figures 4 and 5 describe two construction arrangement variants of a first embodiment of a connection system 10 for connecting the various elements E mentioned above of the frame 1 mentioned above.

[0035] In such an embodiment, the connection system 10 comprises a pair of fixing masks 10', 10" connected together by fixing means 11 housed inside the openings 12 made in the fixing masks 10', 10".

[0036] Each pair of masks 10', 10" comprises a main plate 10a and a pair of side walls 10b extending from at least a portion of the perimeter of the main plate 10a. The main plate 10a and the side walls 10b are formed to allow cooperation in contact with the particular geometric arrangement of the walls of the elements E which need to be connected together and define the openings 12 mentioned above.

[0037] With reference to [Fig.4], a connection system 10 is disclosed, configured to allow connection between four elements E, namely a main element Ea and three secondary elements Eb, Ec, Ed. In the disclosed embodiment, the secondary elements Eb, Ec, Ed and the main element Ea are contained in the same plane and the secondary elements Eb, Ec, Ed extend away in different directions from the main element Ea.

[0038] Consequently, the main plate 10a of the embodiment of [Fig.4] has a main longitudinal part configured to cooperate with the main element Ea and the three secondary parts extending from the main longitudinal part, configured to cooperate with the secondary elements Eb, Ec, Ed.

[0039] The side walls 10b extend substantially from the entire perimeter of the main plate 10a, except at the corners where the side walls 10b are separated or joined by a part of a joint 10c which is preferably curved.

[0040] The openings 12 are made on the radial ends of the masks 10', 10" on each side wall 10b and the central plate 10a and are aligned linearly with each other along a radial and circumferential direction with respect to the center of the mask 10', 10".

[0041] The fastening means 11 are preferably rivets or any equivalent fastening means such as screws or bolts.

[0042] With reference to [Fig.5], a connection system 10 is disclosed, configured to allow connection between two elements E, namely a pair of elements Ef, Eg, connected at their ends in an incidental manner, for example perpendicular to each other.

[0043] Therefore, each mask 10', 10” comprises a main plate 10a and a pair of side walls 10b having substantially the same function as the arrangement of [Fig.4],

[0044] At their longitudinal ends, the masks 10', 10" define the openings 12 which are made on each side wall 10b and the central plate 10a. In the disclosed arrangement, the openings 12 are aligned linearly with each other along a radial and circumferential direction with respect to the center of the mask 10', 10".

[0045] Figures 6 and 7 disclose two alternative construction arrangements of a second embodiment of a connection system 20 for connecting the various elements E mentioned above of the frame 1 mentioned above.

[0046] In such an embodiment, the connection system 20 comprises a plurality of fixing masks 20', 20”, 20”' connected to the elements E by gluing.

[0047] Non-limiting examples of bonding materials are epoxy, acrylic, methane, polyurethane adhesives.

[0048] Each fixing mask 20', 20' ', 20' ' ' comprises at least a first wall 20a and a second wall 20b connected together incidentally, for example orthogonally and formed to follow the geometric arrangement of the elements E connected together.

[0049] The fixing masks 20', 20' ', 20' ' ' can further include a joint portion 20c configured to connect a first and a second wall which are not connected in a perpendicular manner to each other.

[0050] The fixing masks 20', 20”, 20'” may further include a third wall 20d incident with respect to at least one between the first and second walls 20a, 20b.

[0051] The walls 20a, 20b, 20c are configured to cooperate in contact with the elements to be connected by interposition with the glue mentioned above.

[0052] With reference to [Fig. 6], a connection system 20 is disclosed, configured to allow connection between three elements Ei, Eh, Ej via three masks 20', 20", 20"' formed to allow connection of the three elements in the form of a "T", and another connection system 20 is disclosed, configured to allow connection between one of the three elements Ej mentioned above and the three other elements El, Em, En, which extend outward from element Ej, diverging from each other. This other connection system 20 comprises four masks 20', 20", 20"' configured to be fixed to the different sides of the elements Ej, El, Em, En to allow their mutual attachment.

[0053] Figure 7 describes a connection system 20 configured to connect five elements Eo, Ep, Eq, Er, Es. Such a connection system comprises three masks 20', 20", 20" configured to surround different sides of the five elements Eo, Ep, Eq, Er, Es to allow their mutual attachment. In such a case, one of the masks 20' comprises three walls 20a, 20b, 20c, and one of the masks 20" has a first wall 20a that extends over all five elements Eo, Ep, Eq, Er, Es.

[0054] As mentioned, the 10', 20' masks can have different shapes, as illustrated in Figures 8, 9 and 10, which describe different shapes of folded 10', 20' masks.

[0055] An example of the frame 1 which can be arranged via the connection system 10, 20, is shown in [Fig.3]. It should be noted that the frame 1 can constitute the support structure for a roof and side walls of a public transport vehicle, and if necessary for its front and rear walls.

[0056] Such a frame 1 comprises a pair of longitudinal external side elements 2 which are made via a plurality of elements E connected together via the connecting system 10, 20. In the example shown, such longitudinal external sides 2 are made via elements E having different extensions along the longitudinal axis A of the vehicle.

[0057] The external longitudinal lateral elements 2 are connected transversely along the axis A, in particular perpendicularly, via a plurality of cross bars 3 which are made via a plurality of elements E connected together via the connection system 10, 20. In the example shown, such cross bars 3 are made via elements E having different extensions along the transverse direction, mentioned above.

[0058] The frame 1 further comprises an internal longitudinal bar 4 which extends parallel to the lateral elements 2, transversely contained between them and formed by means of a plurality of elements E connected together via the system of connection 10, 20. In the example shown, such an internal longitudinal bar 4 is made via elements E having different extensions along the longitudinal axis A of the vehicle.

[0059] The frame 1 advantageously comprises inclined bars 5, 6, connected, in an operational manner, between at least one of the transverse bars 3, the longitudinal lateral elements 2 and the internal longitudinal bar 4.

[0060] Such inclined bars 5, 6 are generally made in the form of a single element E which is connected, at its end, to the previously mentioned parts of the frame 1, via a connection system 10, 20.

[0061] The inclined bars 5,6 are arranged relative to each other to define a plurality of rhombus shapes along the longitudinal axis A. In particular, such rhombuses can connect, globally, together the longitudinal lateral elements 2, via cross bars 3 and the internal longitudinal bar 4 or simply connect together a plurality of cross bars 3 and the longitudinal bar 4.

[0062] Through the use of the connecting system 10, 20, the elements E can be made of different materials, such as metal or plastic / polymers. In particular, different metals and different plastics / polymers can be used in the same frame 1.

[0063] The operation of the innovation implementation method, as described above, is as follows.

[0064] The frame 1 can be assembled by the connection system 10, 20, in particular by placing masks 10', 20' formed to follow the required connection shape and fixing these by fixing means 11 or by gluing.

[0065] Taking into account the above, the advantages of a connection system and a related framework according to innovation emerge more clearly.

[0066] Thanks to the use of the connection system, welding between the elements of which the frame is composed is avoided.

[0067] Therefore, there is no need to provide sufficient thickness in such elements and there is no need to use specific metals; in particular, a different and lighter material can be used.

[0068] Furthermore, there is no need for specific operations such as cataphoresis to reduce corrosion caused by welding and there is no risk of thermal deformation in the previously mentioned elements always related to welding.

[0069] Furthermore, since no welding is required, there is less energy / gasoline consumption during the manufacture of the roof composed of a frame, as known in art.

[0070] Consequently, the overall manufacturing cost is reduced since the frame assembly is simpler and faster. Indeed, the proposed connection system can be adapted to different geometries and to complex geometries that might be difficult to weld.

[0071] Furthermore, the overall weight of the frame can be reduced. For example, the illustrated frame supplied with components of varying lengths and materials can save approximately 50 kg compared to existing frames.

[0072] In addition to what is mentioned above, the strength of the frame is the same as existing frames or can be further increased due to the new particular geometries that can be provided via such connection systems.

[0073] It is clear that modifications can be made to the described connection system and the related frame, which do not extend beyond the scope of protection defined by the claims.

[0074] As largely explained, the shape and number of masks of the connection system can vary according to the shape and number of elements to be connected together.

[0075] Any material that provides sufficient mechanical resistance for the vehicle field can be used for the masks and frame elements.

[0076] The shape of the frame parts may vary within the limits of the claims below and clearly the dimensions and number of elements of such a frame depend on the use and size of the vehicle.

Claims

Claims

1. Frame (1) for a public transport vehicle extending along a longitudinal axis (A), comprising a plurality of elements (E) connected together, via a connection system (10, 20), said elements (E) being made of materials different from each other, wherein: said frame (1) comprises: a pair of longitudinal lateral elements (2) extending parallel to said longitudinal axis (A), said longitudinal lateral elements (2) being made by connecting together, via said connection system (10, 20), a plurality of elements (E); a plurality of transverse bars (3) extending transversely to said longitudinal axis (A), said transverse bars (3) being made by connecting together, via said connection system (10, 20), a plurality of elements (E);a plurality of inclined bars (5, 6) operatively connected between at least one of said transverse bars (3), said longitudinal lateral elements (2) and an internal longitudinal bar (4), wherein said inclined bars (5, 6) are made with a single element (E) connected at its ends to at least one of said transverse bars (3), said longitudinal lateral elements (2) and said internal longitudinal bar (4).;

2. A frame according to claim 1, wherein said materials comprise metals and plastic / polymers.

3. A frame according to claim 2, comprising different metals and different plastics / polymers.

4. Frame according to any one of claims 1 to 3, comprising an internal longitudinal bar (4) extending parallel to said longitudinal axis (A) and transversely between said longitudinal lateral elements (2), said internal longitudinal bar (4) being produced by connecting together, via said connection system (10, 20), a plurality of elements (E).

5. A frame according to any one of claims 1 to 4, wherein said inclined bars (5, 6) are arranged relative to each other so as to define diamonds along said longitudinal axis (A).

6. Frame according to any one of the preceding claims, wherein said connection system (10, 20) comprises at least one mask (10', 20') comprising at least one first wall (10a) and one second wall (10b) configured to be fixed to at least one pair of elements (E) to fix these latter sets.

7. Frame according to claim 6, wherein said at least one mask (10', 20') is connected to one of the elements (E) via fixing means (11) or by gluing.

8. A vehicle comprising a frame (1) according to any preceding claim.

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