Cross-Reference to Related Applications

This patent application claims priority of Italian Patent Application No. 102021000015452 filed on June 14, 2021, the entire disclosure of which is incorporated herein by reference.

Technical Field of the Invention

The present invention concerns a cross member assembly of a chassis for a heavy vehicle, in particular a heavy vehicle with, at least in part, electric traction.

The present invention finds its preferred, although not exclusive, application in electric traction trucks. Reference will be made to this application by way of example below.

State of the Art

Heavy vehicles such as trucks are more and more electrified in order to reduce the use of internal combustion engine in view of their polluting emissions. The electrification foresees the presence of electrical machines configured to provide torque to the wheels of the vehicle and related batteries configured to store electrical energy to be used/provided by the electric machines.

The batteries are usually carried by the chassis of the vehicle and tends to occupy all the useful spaces. In view of the preceding, other elements such as inverters or electronic control unit needs to be displaced with respect to the batteries.

However, such displacement implies longer electrical connections with consequent increase of costs and needs of complex assembly operation.

Furthermore, longer electrical cable connections increases the possibilities of failures and loss of electrical efficiency. Therefore, the need is felt to improve the existing disposition of electrical groups for vehicles with electric traction.

An aim of the present invention is to satisfy the above mentioned needs in a cost effective and optimized way. Subject and Summary of the Invention

The aforementioned aim is reached by a chassis and a vehicle as claimed in the appended set of claims.

Brief Description of the Drawings

For a better understanding of the present invention, a preferred embodiment is described in the following, by way of a non-limiting example, with reference to the attached drawings wherein:

- Figure 1 is a rear view of an electrical group making part of the cross member assembly according to a first embodiment of the invention; - Figure 2 is a top view of the electrical group of figure 1; - Figure 3 is a rear view of the cross-member assembly comprising the electrical group of figure 1; - Figure 4 is a rear view of an electrical group making part of the cross member assembly according to a first embodiment of the invention; - Figure 5 is a top view of the electrical group of figure 4; - Figure 6 is a rear view of the cross-member assembly comprising the electrical group of figure 4; - Figure 7 is a rear view of an electrical group making part of the cross member assembly according to a first embodiment of the invention; - Figure 8 is a top view of the electrical group of figure 7; - Figure 9 is a rear view of the cross-member assembly comprising the electrical group of figure 7; - Figure 10 is a rear view of an electrical group making part of the cross member assembly according to a first embodiment of the invention; - Figure 11 is a top view of the electrical group of figure 10; and - Figure 12 is a rear view of the cross-member assembly comprising the electrical group of figure 10. Detailed Description of Preferred Embodiments of the Invention The attached figures discloses different embodiment of a cross member assembly 1 according to the invention for a heavy vehicle. In all embodiment, the cross member assembly 1 essentially comprises an electrical group 2 and a fixing plate 3. As can be better appreciated by figures 3, 6, 9 and 12, the fixing plate 3 can be fixed to a chassis 6 of the vehicle, in particular in a transversal direction with respect to a longitudinal axis of the chassis 6. In particular, the chassis 6 comprises a first, left, side member 7 and a second, right, side member 8 parallel one with respect to the other and symmetrically placed with respect to axis A. As per se known, each side member 7, 8 has a C-shaped profile and comprises an upper wall 7a, 8a a lower wall 7b, 8b and a lateral wall 7c, 8c. Each side member 7, 8 therefore defines a space 7’, 8’ vertically delimited between upper and lower walls 7a, 8a, 7b, 8b, transversally delimited by lateral wall 7c, 8c and opened towards the opposite side member. The fixing plate 3 extends transversally with respect to axis A and cooperates with side members 7, 8 to allows its fixation to these latter. In particular, the fixing plate comprises a pair of terminal portions 3b cooperating at contact with side members 7, 8 and an intermediate portion 3a longitudinally comprised between the pair of terminal portions 3b. In particular, the terminal portions 3b are housed within the spaces 7’, 8’ and are fixed to the respective side members, in known manner, e.g. by screws. Both the intermediate portion 3a and the terminal portion 3b comprises a longitudinal wall 3’ and an upper wall 3’’ and the terminal portions 3b further comprises respective lateral walls 3’’’. In particular, fixing plate 3 defines a space 9 vertically delimited by upper wall 3’’ and opened towards ground and laterally delimited by lateral walls 3’’’. The space 9 is configured to house the above mentioned electrical group 2. In particular, at least part of the electrical group 2 is shield by the longitudinal wall 3’ that protects the electrical group from the environment. The electrical group 2 advantageously comprises at least one inverter 11’, 11’’, a power distribution unit 12 and an electrical energy converter 13. In particular, the at least one inverter 11', 11'' may be fixed to fixing plate 3 via mechanical connection means, e.g. via threaded means such as screws. Preferably, also power distribution unit 12 and electrical energy converter 13 are further fixed side members 7, 8. In detail, the power distribution unit 12, or PDU as known, comprises at least a connector module configured to allow the electrical connection with cables to the batteries/electrical machines (not shown) of the vehicle. Similarly, the electrical energy converter 13 comprises at least a connector module configured to allow the electrical connection with cables to the batteries/electrical machines (not shown) of the vehicle. The electrical energy converter 13 is preferably a HV AC converter. The power distribution unit 12 is fixedly carried to the inverter 11’, 11’’ housing via first connection means 15 and similarly the electrical energy converter 13 is connected via second connection means 14. First and second connection means 14, 15 are preferably mechanical connection means, e.g. walls connected to the respective elements via threaded connection and configured to allow the passage of electrical cables within. The power distribution unit 12 and the electrical energy converter 13 is connected to the at least one inverter 11’, 11’’ according to the space that is available on the vehicle and, partially, in space 9. Similarly, the at least one inverter 11’, 11’’ is housed in the space 9 according to the need of space available on the vehicle. Preferably, the space 9 is opened towards a front portion of the vehicle and the electrical group 2 extends vertically towards ground. According to a first embodiment, shown in figure 1, the electrical group 2 comprises two inverters 11’, 11’’ disposed one above the other along a vertical direction. Both the power distribution unit 12 and the electrical energy converter 13 comprises three modules 12’, 12’’, 12’’, 13’, 13’’, 13’’’ disposed one above the other along the vertical direction and comprising two connectors each, one above the other always in the vertical direction. In particular, the connectors extends in longitudinal direction. Both the power distribution unit 12 and the electrical energy converter 13 are directly connected via, respectively, two mechanical connection means 14, 15, namely an upper and a lower connection means to the inverters 11’, 11’’. In particular the connection means may be provided as part of the metal boxes that defines the inverters 11’, 11’’, the power distribution unit 12 and the electrical energy converter 13. Such part of metal boxes may be connected together via mechanical connection means, e.g. threaded means such screws, preferably further glued to isolate the electrical components In vertical direction both the power distribution unit 12 and the electrical energy converter 13 extends similarly as the two inverters 11’, 11’’. Making reference to figure 2, the power distribution unit 12 is substantially coplanar in its rear portion with the two inverters 11’, 11’’ and has a longitudinal extension frontwards that is shorter with respect to these Latter. Conversely, the electrical energy converter 13 is places advanced in front direction with respect to the two inverters and is substantially coplanar in its front portion. According to a second embodiment, shown in figure 4, the electrical group 2 comprises two inverters 11’, 11’’ disposed one above the other along a vertical direction. The power distribution unit 12 comprises three modules 12’, 12’’, 12’’’ disposed one above the other along the vertical direction and the electrical energy converter 13 comprises two modules 13’, 13’’ disposed one above the other along the vertical direction. In particular, the three modules 12’, 12’’, 12’’’ of the power distribution unit 12 comprising two connectors each, one above the other always in the vertical direction and the two modules 13’, 13’’ of the electrical energy converter 13 comprises three connectors each disposed one adjacent the other along transversal direction. In particular, all connectors extends along longitudinal direction. Both the power distribution unit 12 and the electrical energy converter 13 are connected via, respectively, two connection means 14, 15, namely an upper and a lower connection means. In vertical direction the power distribution unit 12 extends similarly as the two inverters while the electrical energy converter 13 extends to the same extension of the upper inverter 11’. Accordingly, the connection means 14 provides an extension to reach the lower inverter 11’’. Making reference to figure 5, the power distribution unit 12 is substantially coplanar in its rear portion with the two inverters 11’, 11’’ and has a longitudinal extension frontwards that is shorter with respect to these latter. Conversely, the electrical energy converter 13 is places advanced in front direction with respect to the two inverters and is substantially coplanar in its front portion. According to a third embodiment, shown in figure 7, the electrical group 2 comprises two inverters 11’, 11’’ disposed one above the other along a vertical direction. The power distribution unit 12 comprises three modules 12’, 12’’, 12’’’ disposed one above the other along the vertical direction and the electrical energy converter 13 comprises two modules 13’, 13’’ disposed one above the other along the vertical direction. In particular, the three modules 12’, 12’’, 12’’’ of the power distribution unit 12 comprising two connectors each, one above the other always in the vertical direction and the two modules 13’, 13’’ of the electrical energy converter 13 comprises three connectors one above the other always in the vertical direction. In particular, all connectors of the power distribution unit 12 extends along longitudinal direction while the connector of the second, lower, module 13’’ of the electrical energy converter 13 extends transversally, in detail towards the lower inverter 11’’. Both the power distribution unit 12 and the electrical energy converter 13 are connected via, respectively, two connection means 14, 15, namely an upper and a lower connection means. In vertical direction both the power distribution unit 12 and the electrical energy converter 13 extends similarly as the two inverters 11’, 11’’. Making reference to figure 8, the power distribution unit 12 is substantially coplanar in its rear portion with the two inverters 11’, 11’’ and has a longitudinal extension frontwards that is shorter with respect to these latter. Conversely, the electrical energy converter 13 is places advanced in front direction with respect to the two inverters and is substantially coplanar in its front portion. According to a fourth embodiment, shown in figure 10, the electrical group 2 comprises two inverters 11’, 11’’ disposed one above the other along a vertical direction. The power distribution unit 12 comprises three modules 12’, 12’’, 12’’’ disposed one above the other along the vertical direction and the electrical energy converter 13 comprises two modules 13’, 13’’ disposed one above the other along the vertical direction. In particular, the three modules 12’, 12’’, 12’’’ of the power distribution unit 12 comprising two connectors each, one above the other always in the vertical direction and the two modules 13’, 13’’ of the electrical energy converter 13 comprises three connectors adjacent one to the other in transversal direction. In particular, all connectors extends along longitudinal direction, Both the power distribution unit 12 and the electrical energy converter 13 are connected via, respectively, two connection means 14, 15, namely an upper and a lower connection means. In vertical direction both the power distribution unit 12 and the electrical energy converter 13 extends similarly only as the upper inverter 11’. Accordingly, they are both connected to the lower inverter 11’’ via extensions of the connection means 14, 15. Making reference to figure 11, the power distribution unit 12 is substantially coplanar in its rear portion with the two inverters 11’, 11’’ and has a longitudinal extension frontwards that is shorter with respect to these latter. Conversely, the electrical energy converter 13 is places advanced in front direction with respect to the two inverters and is substantially coplanar in its front portion. In view of the foregoing, the advantages of a chassis according to the invention are apparent. The proposed cross member assembly 1 solves both the function of cross member between side members 7, 8 and of housing for the electrical groups 2. In detail, the proposed structure is configured to allow the fixation of the electrical groups 2 with a wide variety of possible orientation types. Accordingly, it may be used for different vehicles configurations. Since the fixing plate covers main parts of the inverter, the electrical energy converter 13 and the PDU 12, it acts also as protection against hurts coming from the environment. Since the electrical groups 2 are placed in the chassis area, i.e. near to the electrical machines and batteries, there is less need of electrical wires thereby reducing weight of the cables and voltage needed. It is clear that modifications can be made to the described chassis that do not extend beyond the scope of protection defined by the claims. As said, electrical groups may be placed in different orientations according to the vehicular needs. Furthermore, the shapes and cross-sections of the shown elements, or their number, may vary within the claimed limits.