ITBO20090015A1 - VEHICLE WITH HYBRID PROPULSION - Google Patents

Description

DESCRIPTION

of the patent for industrial invention entitled:

"VEHICLE WITH HYBRID PROPULSION"

TECHNIQUE SECTOR

The present invention relates to a vehicle with hybrid propulsion.

ANTERIOR ART

A hybrid vehicle comprises an internal combustion engine, which transmits the drive torque to the drive wheels by means of a transmission equipped with a gearbox, and at least one electric machine which is mechanically connected to the drive wheels. The electric machine is driven by an electric drive connected to an electric storage system typically consisting of a pack of chemical batteries possibly connected in parallel to one or more supercapacitors.

While the vehicle is running, it is possible: a thermal operating mode, in which the drive torque is generated only by the combustion engine and possibly the electric machine acts as a generator to recharge the electrical storage system, an electric operating mode, in which the combustion engine is off and the engine torque is generated only by the electric machine operating as an engine; or a combined operating mode, in which the driving torque is generated both by the combustion engine and by the electric machine operating as an engine. Furthermore, to increase the overall energy efficiency during all the deceleration phases, the electric car can be used as a generator to realize a regenerative deceleration in which the kinetic energy possessed by the vehicle instead of being completely dissipated in friction is partially converted into electrical energy that is stored in the electrical storage system.

The placement of the storage system inside the vehicle can be very complex, particularly in the case of a high-performance sports vehicle that has very limited interior spaces. In particular, the storage system must possibly be placed near the electric machine and the electric drive to reduce the length of the electrical connection cables (therefore to reduce the weight of the electric cables and the power losses due to the Joule effect in the electric cables themselves), must possibly be placed in a position protected from impacts, must be placed in a position sheltered from heat sources as it cannot withstand high temperatures, and must be arranged in such a way as not to unbalance the balance of the vehicle with its own relevant mass ( in other words, as close as possible to the center of gravity and to the ground to obtain a good dynamic behavior of the vehicle).

In known vehicles, the above-described constraints force the batteries of the storage system to be arranged in non-optimal positions and in any case considerably limit the usable space for the batteries of the storage system; consequently, the capacity of storing electric energy of the accumulation system is limited and consequently also the possibilities of use of the electric machine are reduced.

DESCRIPTION OF THE INVENTION

The object of the present invention is to provide a vehicle with hybrid propulsion, which is free from the drawbacks described above and is at the same time easy and economical to manufacture.

According to the present invention, a vehicle with hybrid propulsion is provided as claimed in the attached claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the attached drawings, which illustrate some non-limiting examples of implementation, in which:

• figure 1 is a schematic plan view with parts removed for clarity of a vehicle with hybrid propulsion made in accordance with the present invention, - • figure 2 is a further schematic view, in plan and with parts removed for clarity of the vehicle of Figure 1;

Figure 3 a schematic side view of the vehicle of figures 1 and 2;

Figure 4 is a transversal section, schematic and with parts removed for clarity of a lower portion of the vehicle of figure 1 along the line XV-XV;

• figures 5-9 are cross sections, schematic and with parts removed for clarity of some construction variants of the lower portion of figure 4; Figure 10 is a schematic plan view with parts removed for clarity of a further variant of the vehicle of Figure 1;

Figure 11 is a cross section, schematic and with parts removed for clarity of a lower portion of the vehicle of figure 1 along the line XI-xi; And

Figure 12 is a transversal section, schematic and with parts removed for clarity of a construction variant of the lower portion of figure 11.

PREFERRED EMBODIMENTS OF THE INVENTION

In figure 1, the number 1 indicates as a whole a vehicle with hybrid propulsion provided with two front wheels 2 and two rear driving wheels 3, which receive the drive torque from a hybrid propulsion system 4.

the hybrid propulsion system 4 comprises an internal combustion thermal engine 5, which is arranged in the front position and is provided with a drive shaft 6, a servo-controlled transmission 7, which transmits the drive torque generated by the internal combustion engine 5 towards the 3 rear driving wheels, and a reversible electric machine 8 (i.e. which can operate both as an electric motor by absorbing electrical energy and generating a mechanical driving torque, and as an electric generator by absorbing mechanical energy and generating electrical energy) which is mechanically connected to the transmission 7 servo-controlled.

The servo-controlled transmission 7 comprises a transmission shaft 9 which is on one side angularly integral with the motor shaft 6 and on the other side is mechanically connected to a gearbox 10, which is arranged in a rear position and transmits motion to the wheels 3 rear drive by means of two half-shafts 11 which receive motion from a differential 12. The reversible electric machine 8 is mechanically connected to the gearbox 10 and is piloted by an electric drive 13 connected to an accumulation system 14 (illustrated in Figure 2), which it is suitable for storing electrical energy and comprises a series of storage devices 15 which in turn comprise chemical batteries and / or supercapacitors.

According to what is illustrated in Figure 2, the vehicle 1 is provided with a frame 16 which directly supports the propulsion system 4 and rests on the front wheels 2 and on the rear wheels 3 through the interposition of respective front suspensions 17 and respective rear suspensions 18. .

According to what is illustrated in Figure 3, the vehicle 1 comprises a body 19 which covers the frame 16, defines a passenger compartment 20 and has at least two doors 21 for accessing the passenger compartment 20 itself. Below each door 21, a respective sill 22 is defined (i.e. the lower part of the sill extending from the end of the front wheel arch to the beginning of the rear wheel arch), in which a longitudinal side member 23 is arranged (illustrated in Figures 2 and 4) of the frame 16 which is therefore arranged at a lateral edge of the frame 16 below a door 21.

According to what is illustrated in Figures 2 and 4, the vehicle 1 comprises a central tunnel 24, which is fixed to the frame 16 to form a structural part of the frame 16, runs centrally and longitudinally from the internal combustion engine 5 to the gearbox 10 and houses the drive shaft 9. Furthermore, the vehicle 1 comprises a platform 25, which is fixed to the frame 16 to constitute a structural part of the frame 16 itself and constitutes a bottom wall of the passenger compartment 20.

The platform 25 comprises two boxed bodies 26, each of which is preferably made by extrusion, has a tubular shape with a rectangular section, and comprises two horizontal base plates 27 parallel to each other and spaced apart which define an internal seat 28 between them, the accumulation devices 15 are housed in the internal seat 28 of each boxed body 26. Each boxed body 26 could also comprise one or more internal walls (not shown), which are arranged between the two sheets 27 perpendicular to the sheets 27 themselves to increase the mechanical strength of the boxed body 26. Above each box-shaped body 27 there is a covering 29, which constitutes a finish of the passenger compartment 20 and in particular constitutes a visible flooring of the passenger compartment 20. It is important to note that the function of the box-shaped bodies 26 is not only that of contain the storage devices 15, but the boxed bodies 26 also have an important structural function, contributing to a not negligible increase in the overall stiffness of the frame 16.

According to what is illustrated in Figure 2, the accumulation system 14 comprises six accumulation devices 15, which are symmetrically distributed inside the two boxed bodies 26; obviously, depending on the characteristics of the vehicle 1, the number and / or arrangement of the storage devices 15 can vary.

As shown in Figure 4, each boxed body 26 is fixed laterally to a respective longitudinal member 23 and centrally to the central tunnel 24 by means of a series of screws 30. According to the embodiment illustrated in Figure 4, each longitudinal member 23 comprises a lateral shelf 31 which protrudes from the longitudinal member 23 itself towards the central tunnel 24 and constitutes a support for the corresponding boxed body 26; furthermore, the central tunnel 24 comprises a pair of central brackets 32, which are arranged on opposite sides of the central tunnel 24 projecting from the central tunnel 24 towards the longitudinal members 23 to form a support for the boxed bodies 26. The screws 30 establish a rigid connection between the shelves 31 and 32 and the boxed bodies 26.

According to a preferred embodiment, each storage device 15 has a parallelepiped shape and has a heating base wall 33, which is horizontal and has no thermal insulation, and a non-heating base wall 34, which is horizontal , is parallel and opposite to the heating base wall 33 and is provided with a layer 35 of thermally insulating material. According to a first embodiment, the non-heating base wall 34 is always turned upwards to be in contact with the upper base plate 27 on which the covering 29 rests (hence the base plate 27 which looks towards the passenger compartment 20) and the heating base wall 33 is always facing downwards to be in contact with the lower base plate 27 which delimits the bottom of the vehicle 1 and which therefore is in contact with the external environment, in this way, the heat produced during use by each storage device 15 does not enter the passenger compartment 20 and is vented downwards, being transmitted to the lower base plate 27 which delimits the bottom of the vehicle 1 and being constantly lapped by the air, it is naturally cooled .

According to a different embodiment, each boxed body 26 is made with a symmetrical one that allows the overturning of the boxed body 26 itself so that the heating base wall 33 can be indifferently disposed upwards (i.e. towards the passenger compartment 20 ) or downwards (i.e. towards the outside); in this way, depending on the season (summer or winter), it is possible to choose whether to arrange the heating base wall 33 downwards to disperse the heat produced during use by the storage device 15 outside (summer season), or whether to arrange the heating base wall 33 upwards to convey the heat produced during use by the storage device 15 inside the passenger compartment 20 (winter season). This embodiment which provides for the summer / winter reversibility of the boxed bodies 26 (therefore of the storage devices 15) maximizes the energy efficiency of the storage devices 15 allowing, when useful, the recovery of the heat produced during use.

According to a possible embodiment, the two boxed bodies 26 which are arranged on opposite sides of a longitudinal axis of the vehicle 1 (i.e. on opposite sides of the central tunnel 24) are made in such a way that to overturn the boxed bodies 26 it is necessary to make a right-left inversion of the box-like bodies 26 themselves; in other words, the box-like body 26 disposed to the right must be moved to the left and vice versa. This embodiment is indispensable when the boxed bodies 26 do not have a rectangular base which allows a high symmetry, but have a trapezoidal base to follow the shape of the frame 16.

To allow the disassembly and subsequent reassembly of the boxed bodies 26, nothing or in any case the minimum indispensable is fixed to the boxed bodies 26. In particular, the seats (not shown) of the vehicle 1 are not rested inferiorly to the boxed bodies 26, but are laterally fixed to the longitudinal members 23 and to the central tunnel 24 and "float" above the boxed bodies 26; this constructive choice is particularly simple when the front seats of the vehicle 1 are arranged in a fixed position while a pedal unit and a steering wheel (not shown) are mounted in an adjustable position to adapt to the height of the driver.

According to a preferred embodiment, each boxed body 26 could comprise a series of vertical fins 36, which are arranged longitudinally (i.e. parallel to the forward direction of the vehicle 1) and project downwards from the lower base plate 27; the function of the fins 36 is to increase the heat exchange between the lower base plate 27 and the external environment by increasing the exchange surface and to create between the fins 36 themselves channels in which to channel the air under the floor 25 to improve the overall aerodynamics of the vehicle 1 (for this last function the fins 36 could also be slightly inclined so as to define channels with variable section). The fins 36 can be rigidly fixed (for example welded) to the lower base plate 27 in the case in which the boxed bodies 26 are fixed (i.e. not removable) or they can be fixed in a detachable way (typically by means of screws) to be once disassembled from the base plate 27 which must be placed in the upper position and reassembled on the base plate 27 which must be arranged in the lower position when the boxed bodies 26 are overturned as described above.

The embodiment illustrated in Figure 5 differs from the embodiment of Figure 4 for the position of the shelves 31 and 32, which constitute a lower support in the embodiment of Figure 4 and constitute an upper attachment point in the embodiment of Figure 5. Consequently, in the embodiment of Figure 4 the boxed bodies 26 must be inserted from above while in the embodiment of Figure 5 the boxed bodies 26 must be inserted from below.

The embodiments illustrated in figures 6 and 7 differ from the embodiment of figure 4 due to the conformation of the platform 25 which provides two boxed bodies 26 in the embodiment of figure 4 and a single boxed body 26 of double width in the embodiments of implementation of figures 6 and 7. in particular, in the embodiment of figure 6 the boxed body 26 is welded to the longitudinal members 23 and to the central tunnel 24 by means of welds 37 (therefore the boxed body 26 cannot be disassembled) while in the embodiment of Figure 6, the boxed body 26 is fixed by means of the screws 30 (therefore the boxed body 26 can be dismantled).

The embodiments illustrated in figures 8 and 9 differ from the embodiment of figure 4 due to the shape of the platform 25 which provides two boxed bodies 26 in the embodiment of figure 4 and a single boxed body 26 of double width in the embodiments of embodiment of figures 8 and 9. in particular, in the embodiments of figures 8 and 9 the boxed body 26 encompasses and is one with the central tunnel 24, - obviously in these embodiments the boxed body 26 is not reversible ( i.e. it is not possible to invert the heating base wall 33 with the non-heating base wall 34) due to an evident lack of symmetry.

According to the different embodiment illustrated in Figures 10 and 11, each boxed body 26 comprises an inlet duct 38, which is arranged in the front position, is regulated by a servo-controlled regulation valve 39, and is adapted to convey a flow of moreover, each boxed body 26 comprises an outlet duct 40, which is arranged in a rear position and is able to extract a flow of air from inside the boxed body 26 itself. Inside each boxed body 26 there is defined an interspace 41, which runs from the inlet duct 38 to the outlet duct 40 and is able to be crossed by a flow of air.

According to the embodiment illustrated in Figure 11, inside each boxed body 26 the function of the interspace 41 is to provide thermal insulation between the storage devices 15 and the upper base wall 27 so as to prevent the heat produced during use by each storage device 15 is transmitted to the passenger compartment 20. Each inlet duct 38 originates from a dynamic air intake which is adapted to collect and convey air while the vehicle 1 is running, while each outlet duct 40 terminates in a vent of air to the outside.

When the regulating valves 39 are closed there is no exchange of air inside the boxed bodies 26, therefore the heat produced during use by the storage devices 15 is vented only downwards through the lower base wall 27 while the air present between the storage devices 15 and the upper base wall 27 heats up progressively, consequently also causing a progressive heating of the upper base wall 27 and therefore of the passenger compartment 20. On the other hand, when the regulating valves 39 are open there is a continuous exchange of air inside the boxed bodies 26, therefore the heat produced during use by the storage devices 15 is vented both downwards through the lower base wall 27, and upwards through the flow of air; consequently, there is no heat transmission from the storage devices 15 to the upper base wall 27 and therefore to the passenger compartment 20.

As described above, by varying the position of the regulation valves 39 it is possible to choose whether the heat produced during use by the storage devices 15 must be partially directed towards the passenger compartment 20 (closed regulation valves 39) or completely vented towards the external (control valves 39 open). Furthermore, in the event of particularly high external temperatures (ie in the case of the summer season in hot climates), thanks to the possibility of internally ventilating the boxed bodies 26, it is possible to avoid excessive overheating of the storage devices 15.

In the variant illustrated in Figure 12, a layer 42 of insulating material is provided, arranged in contact with the upper base wall 27 to prevent in any case the heat produced during use by the storage devices 15 is transmitted to the upper base wall 27 itself and therefore to the passenger compartment 20. In this case, the flow of air that passes through the boxed bodies 26 and exits from the outlet ducts 40 can be used, if required, to heat the passenger compartment 20 directly (i.e. the air that exits from the outlet ducts 40 it is introduced into the passenger compartment 20) or indirectly (ie the heat possessed by the air that emerges from the outlet ducts 40 is transferred to an intermediate element which in turn heats the passenger compartment 20); such intermediate element can be, for example, an air / air heat exchanger which heats the air inside the passenger compartment 20 by using the heat possessed by the air that comes out of the outlet ducts 40. In other words, the boxed bodies 26 are internally cooled by a flow of air which can be used, if required, to heat the passenger compartment 20 (possibly with a forced air recirculation system so that the air that escapes from the outlet ducts 40 it is re-introduced by a fan into the inlet ducts 38).

According to a further embodiment not shown, instead of using an air cooling system for the boxed bodies 26, a liquid cooling system (typically water) is used, which has a number of channels that run inside the boxed bodies 26 in contact accumulation devices 15; the heat subtracted from the liquid inside the boxed bodies 26 can be vented to the outside, for example by means of a radiator or it can be used to heat the passenger compartment 20, for example by means of a water / air heat exchanger.

The vehicle 1 described above has numerous advantages, as it is simple and inexpensive to manufacture, being structurally very similar to a similar existing vehicle and above all it offers an optimal location from all points of view to the storage system 14 (i.e. to the storage devices 15 ). First of all, the storage system 14 is extremely protected against impact, as it is arranged inside the safety cell of the passenger compartment 20.

In the vehicle 1 described above, the storage devices 15 are arranged next to the central tunnel 24, therefore the electric cables connecting the storage devices 15 and the electric drive 13 can run inside the central tunnel 24 with a path devoid of tortuosity, very protected and relatively short.

In the vehicle 1 the storage system 14 is arranged in a position which is not subject to overheating and is easily cooled (as previously mentioned, the lower plates 27 of the boxed bodies 26 are constantly lapped by the air while the vehicle 1 is running) .

Finally, in the vehicle 1 the storage system 14 is arranged very close to the center of gravity and very close to the ground in order not to unbalance the balance of the vehicle 1 with its relevant mass. Furthermore, the arrangement of the accumulation system 14 described above allows the height from the ground of the vehicle 1 to be considerably reduced, which is therefore particularly low.

Claims (2)

CLAIMS 1) Vehicle (1) with hybrid propulsion comprising: a passenger compartment (20), - a frame (16) carrying a floor (25) which forms a rear wall of the passenger compartment (20); at least one pair of driving wheels (3); a reversible electric machine (8) mechanically connectable to the driving wheels (3); an electric drive (13) that drives the electric machine (8); and an accumulation system (14), which is adapted to store electric energy, is connected to the electric drive (13) and comprises at least one accumulation device (15); the vehicle (1) is characterized by the fact that the platform (25) comprises at least one boxed body (26), which is fixed to the frame (16) to form a structural part of the frame (16) itself, has a tubular shape with rectangular section, and comprises two horizontal base plates (27) parallel to each other and spaced apart which define between them an internal seat (28) in which the accumulation device (15) is housed. 2) Vehicle (1) according to claim 1 and in which the frame (16) comprises a pair of longitudinal side members (23) arranged at the two lateral edges of the frame (2); the boxed body (26) is fixed laterally to the longitudinal side members (23). 3) vehicle (1) according to claim 2 and comprising a central tunnel (24), which is fixed to the frame (16) to form a structural part of the frame (16) and runs centrally and longitudinally; the platform (25) comprises two boxed bodies (26) separated and independent from each other and arranged on opposite sides of the central tunnel (24); each boxed body (26) is fixed centrally to the central tunnel (24) and laterally to the longitudinal side members (23). 4) vehicle (1) according to claim 2, in which the boxed body (26) integrates a central tunnel (24), which runs centrally and longitudinally. 5) Vehicle (1) according to one of claims 1 to 4, in which the storage device (15) has a heating base wall (33), which has no thermal insulation, and a base wall (34) non-heating, which is parallel and opposite to the heating base wall (33) and is provided with a layer (35) of thermally insulating material. 6) Vehicle (1) according to claim 5, in which the box-like body (26) is made with a symmetrical element which allows the overturning of the box-like body (26) itself so that the heating base wall (33) can be indifferently facing downwards and therefore towards the outside environment or upwards and therefore towards the passenger compartment (20). 7) Vehicle (1) according to claim 6 and comprising two boxed bodies (26), which are arranged on opposite sides of a longitudinal axis of the vehicle (1) and are made in such a way that to overturn the boxed bodies (26) it is necessary to carry out a right-left inversion of the boxed bodies (26) themselves. 8) Vehicle (1) according to claim 6 or 7, in which the vehicle seats (1) are laterally fixed to longitudinal side members (23) of the frame (16) and to a central tunnel (24) and "float" above the boxed bodies (26). 9) Vehicle (1) according to one of claims 1 to 8, in which the boxed body (26) comprises a series of vertical fins (36), which are arranged longitudinally and project downwards from a sheet (27 ) lower base. 10) Vehicle (1) according to one of claims 1 to 8, wherein the boxed body (26) comprises: an inlet duct (38) adapted to convey a flow of air inside the boxed body (26); an outlet duct (40) adapted to extract a flow of air from the inside of the boxed body (26); a gap (41), which is defined inside the boxed body (26), runs from the inlet duct (38) to the outlet duct (40), and is able to be crossed by a flow of air, and a regulating valve (39) for regulating the flow of air from the inlet duct (38) to the outlet duct (40) through the interspace (41). 11) Vehicle (1) according to claim 10, in which the interspace (41) is arranged between the storage device (15) and an upper base wall (27) of the box-like body (26) to form a thermal insulation between the storage device (15) and the upper base wall (27) so as to prevent the heat produced during use by the storage device (15) from being transmitted to the passenger compartment (20). 12) Vehicle (1) according to claim 11, in which the inlet duct (38) originates from a dynamic air intake which is adapted to collect and convey air while the vehicle is running (1), and the duct (40) outlet ends in a vent of air to the outside. 13) Vehicle (1) according to claim 10, 11 or 12, in which the flow of air that passes through the interspace (41) of the boxed body (26) can be used to heat the passenger compartment (20). 14) vehicle (1) according to one of claims 1 to 8 and comprising a liquid cooling system having a number of channels which run inside the boxed bodies (26) in contact with the storage devices (15); the heat subtracted from the liquid inside the boxed bodies (26) can be vented to the outside or can be used to heat the passenger compartment (20).