Field of the invention

The present invention refers to the field of in-vehicle man-machine interfaces and, precisely, of systems for selecting a vehicular traction mode of a hybrid or multimodal vehicle.

Discussion of the prior art

Hybrid vehicles comprise an internal combustion engine and an electric motor connected to the driveline.

In hybrid vehicles, the electric motor cooperates with the internal combustion engine to drive the vehicle by recovering energy under braking or contributing to the torque during propulsion.

Multimodal vehicles are defined as hybrid vehicles which, in addition to the functions described above, can also operate in "purely electric" traction mode, that is to say, with the internal combustion engine deactivated, and in "recharge" mode in which the vehicle is propelled by the internal combustion engine, while the electric generator recharges the batteries.

Clearly, the appropriate commands must be provided on the vehicle's dashboard in order to switch from one mode to the other. Increasingly often these controls are included in specific menus and sub-menus of the on-board computer. Therefore, upon entering an area in which purely electric traction is permitted, the driver must access the menus of the on-board computer to set said mode.

For the sake of convenience, in the following description the terms "purely electric mode" or "purely electric traction mode" will be used to refer to a type of traction in which the internal combustion engine is completely deactivated and the terms "fuel mode" or "fuel traction mode" to indicate traction that envisages the activation, albeit not continuously, of the internal combustion engine. Summary of the invention

The purpose of the present invention is to provide a selection system of a purely electric traction mode of a hybrid or multimodal vehicle that is extremely intuitive and easy to operate.

The idea at the basis of the present invention is to incorporate certain controls in the manual gearbox lever in order to switch from any fuel mode, in which the internal combustion engine is active, albeit not stably or cyclically, to a purely electric mode and vice versa. In particular, the idea is to implement an engagement position of the gearbox control lever that simultaneously selects neutral and the purely electric traction mode.

According to a preferred embodiment of the invention, said engagement position is implemented as an extension of the gear selection travel obtained by overcoming a barrier.

The overtravel position is engaged by overcoming a barrier, preferably by raising a sliding sleeve fitted to the gearbox lever. Alternatively, the barrier is overcome by exerting an axial pressure on the gearbox lever.

According to a preferred embodiment of the invention, there is a push-button on the knob of the gearbox lever which, if pressed during a step of disengagement of said overtravel engagement position, prevents the reactivation of said fuel mode and keeps the purely electric mode enabled. Such method of operation is particularly advantageous when the driver intends to engage the electric reverse gear.

The object of the present invention is a selection system of a vehicular traction mode of a hybrid or multimodal vehicle as claimed in claim 1.

Another object of the present invention is a method of selection of a vehicular traction mode of a hybrid and/or multimodal vehicle.

A further object of the present invention is a hybrid and/or multimodal land vehicle.

The claims describe preferred embodiments of the invention and form an integral part of the present description .

Brief description of the drawings

Further purposes and advantages of the present invention will become clear from the following detailed description of a preferred embodiment (and alternative embodiments) thereof and from the accompanying drawings which are merely illustrative and not limiting, in which: figure 1 shows a gear selection pattern of the gearbox according to the present invention;

figure 2 illustrates a preferred transmission layout implemented in combination with the present invention,

figure 3 shows a support for a gearbox lever and a respective sleeve for implementing the present invention, according to a preferred embodiment thereof.

In the figures the same reference numerals and letters indicate the same parts or components.

Within the scope of the present description, the term "second" component does not imply the presence of a "first" component. Such terms are simply used for the sake of clarity and should not be considered as limiting the scope of the invention.

Detailed description of embodiments of the invention

Figure 1 illustrates a gear selection grid or pattern of a gearbox control-lever configured according to the present invention .

The horizontal line, generally transversal to a longitudinal extension of the vehicle, which permits the selection of gears 1,2 or 3,4 or 5,6, is usually referred to as the "selection travel" and is indicated by the letters LC, while the transverse lines, normally parallel to the longitudinal extension of the vehicle, are called "first gear 1, "second gear 2", etc.

Figure 1 shows a dashed square inside which are the gears from 1 - 6 (or from 1 - 5) , while the reverse gear R and the symbol eD are outside said square. This means that both the reverse gear R and the engagement position eD can only be reached by overcoming a left barrier SB and a right barrier DB, respectively. The concept of barrier and overtravel associated with overcoming the respective barrier is known in the prior art. Thus, in figure 1 it is immediately apparent that the engagement of the reverse gear requires an overtravel to the left and a subsequent forward (or backward) selection travel parallel to the longitudinal extension of the vehicle, while the selection of the position eD only requires an overtravel to the right, without then moving the lever forwards or backwards. There are substantially two known types of barriers for engaging the reverse gear, namely those that require the application of an axial pressure on the gearbox lever and those that involve lifting a sliding sleeve C on the gearbox lever that can usually be reached with the fingers while the holding the palm of the same hand on a portion of the knob .

This precaution prevents the accidental selection of the reverse gear, in order to avoid serious damage to said gearbox .

It must be clear that the method of engagement of the reverse gear is not relevant for the purpose of the present invention. This is only described in order to clarify the aspects it has in common with the engagement eD which is the idea at the basis of the present invention.

According to the present invention the position eD is engaged by overcoming a barrier, preferably of the type with a sliding sleeve C on the gearbox lever L.

According to the present invention, the engagement of the position eD, which is substantially continuous and aligned with the selection travel LC, does not engage any gear of the gearbox, which is left in neutral. Said engagement simultaneously closes an electric contact SS which disables all of the vehicle's fuel traction modes so that only the purely electric mode can be enabled.

According to a preferred embodiment of the invention, on the knob P of the gearbox lever L, shown in figure 2, there is also a normally-open switch associated with a monostable push-button S.

During the operation of the vehicle in fuel traction mode, said push-button enables cycling between two or more different fuel traction modes, which are preferably indicated from time to time on an appropriate display on the vehicle's dashboard.

The concept of cycling is well known to the person skilled in the art, and means that an operating mode can be selected by repeatedly pressing the push-button to select the desired mode. Thus, said push-button S located on the knob of the gearbox lever can be used for example to select "recharge" mode before reaching an area with limited access to traffic in order to store electric power and then, bringing the lever in the position eD, that is overcoming said barrier, the vehicle can be switched to purely electric traction mode.

It is clear that the driver does not need to access complex menus of the on-board computer, but can switch to the purely electric traction mode and vice versa by means of a simple gesture to operate a control device that is frequently used. According to a preferred embodiment of the invention, the vehicle driveline comprises a controllable clutch or coupling CL, preferably of the dog clutch type, located on a transmission shaft T downstream of the gearbox G, that is to say, between the gearbox and a driving axle W and an electric motor generator MG connected to said transmission shaft, downstream of the clutch or coupling, so that the electric motor generator can propel the vehicle without also making the second shaft of the gearbox rotate.

It is apparent that this clutch or coupling CL has nothing to do with the main clutch that disconnects the drive shaft of the internal combustion engine E from the first shaft of the gearbox G.

According to said preferred embodiment of the invention, the engagement of the position eD determines an automatic disengagement of said clutch or coupling.

According to a further preferred embodiment of the invention which is combined with tthose described above, when the push ^¬ button on the gearbox lever knob is held down, reactivation of the fuel mode and re-engagement of said clutch CL or of said coupling is prevented while switching from the position eD to reverse gear, and the purely electric mode is maintained.

Another electric contact is also at least associated with the reverse gear portion, to detect the respective engagement and enable the reversal of the direction of rotation of the motor generator MG.

Therefore, owing to the fact that the knob on the gearbox lever is held down during the disengagement of the position eD until the reverse gear is engaged, the purely electric traction mode is not changed and at the same time a signal is sent to the control unit of the electric motor generator to reverse the direction of rotation of said electric motor generator. Vice versa, if the position eD is disengaged without pressing the push-button S, the previously set fuel mode is re ^¬ activated.

For example, if the previously set mode was "recharge", when the position eD is disengaged, the clutch or coupling CL is reengaged and the internal combustion engine E is re-started. Advantageously, the driver continues to use the gearbox even in the purely electric traction mode, in the same way as in the fuel mode, even though the mechanical functions of the gearbox have absolutely no effect on the traction because said clutch or coupling CL is disengaged.

It is apparent that the operations performed by the driver on the gearbox lever and on the push-button are monitored by a vehicle processing unit VEH which may or may not differ from the processing unit that controls the internal combustion engine ECU.

The arrangement described herein applies to left-hand drive vehicles, but the pattern PT can be implemented symmetrically to that illustrated in figure 1, for right-hand drive vehicles. Figure 3 illustrates a support SP, which is a further object of the present invention, for the gearbox lever L according to a preferred embodiment of the invention. The drawing shows the barriers SB and DB implemented by means of longitudinal profiles parallel to one another which interfere with the sleeve C described above, one to engage the reverse gear and the other to engage the portion of overtravel eD.

Thus, whereas the known supports comprise a single barrier, generally arranged on the side facing towards the driver's leg, according to the present invention, the gearbox lever support comprises two barriers, one on each side.

The present invention may advantageously be implemented by means of a computer program comprising coding means to implement one or more steps of the method, when such program is run on a computer. Thus, the scope of protection includes said computer program and also computer readable means comprising a recorded message, said computer readable means comprising program code means designed to implement one or more of the steps of the method, when said program is run on a computer.

From the above description it will be possible for the person skilled in the art to implement the object of the invention without the need for any additional construction details. The elements and the characteristics illustrated in the different preferred embodiments, including the drawings, may be combined without departing from the scope of protection of the present application. That described in the description of the prior art serves merely to ensure a better understanding of the invention and does not constitute a declaration concerning the existence of that described. Moreover, unless specifically excluded in the detailed description, what is described in the description of the prior art is to be considered in combination with the features of the present invention, thus forming an integral part of the present invention. None of the features of the alternative embodiments are essential. Therefore, the individual features of each preferred embodiment or drawing may be combined with the other embodiments that are described.