FR2975051A1 - Vehicle e.g. electric car, has lever moved between one position in which torque applied to aft wheels of vehicle is equal to maximum value percent and another position in which torque applied to wheels is equal to zero percent - Google Patents

Abstract

The vehicle has a gear selection lever (6) allowing a driver to select the following positions that include a neutral position (N), a reverse position (R) for moving the vehicle along reverse direction, and a forward position (D) for moving the vehicle along forward direction. The lever is moved by the driver continuously between a position in which torque applied to aft wheels of the vehicle is equal to 100 percent of maximum value, and another position in which the torque applied to the wheels is equal to zero percent, in the forward position.

Description

The present invention relates to a motor vehicle with an electric motor or a combustion engine coupled to a robotised gearbox, comprising a lever for selecting a motorcycle and a motor for driving a motor. speed allowing the driver to select the following three positions: - position N (neutral), - position R to reverse the vehicle, - position D to advance the vehicle. Motor vehicles with electric motors have difficulty starting on snow or ice. Indeed, an electric motor has a maximum torque from the start, unlike a heat engine in which the torque increases with the speed of rotation. In addition, electric motor vehicles do not include a clutch for dosing the torque by pressing more or less on the accelerator pedal. Thus, when the accelerator is pressed during start-up, the torque exerted by the engine is such that the wheels slip on the snow immediately, making it impossible to start on a climb. The same difficulty arises in the case of vehicles equipped with a heat engine coupled to a robotized box. Indeed, in these, the clutch is controlled, which also makes it difficult to dose the torque transmitted to the drive wheels. The object of the present invention is to overcome these disadvantages. This object is achieved, according to the invention, by means of a motor vehicle with an electric motor or a combustion engine coupled to a robotized gearbox, comprising a speed selection lever allowing the driver to select the following three positions: position N (neutral), - position R for reversing the vehicle, - position D for advancing the vehicle, characterized in that, in position D, the selector lever is movable by the driver continuously, between a first position in the torque applied to the driving wheels of the vehicle is equal to 100% of the maximum value and a second position in which the torque applied to these wheels is equal to 0%. Thus, the driver of a vehicle equipped with an electric motor or a heat engine coupled to a robotized gearbox can dose the torque applied to the drive wheels by moving the gear lever between the two positions above.

As a result, the driver can prevent the drive wheels from slipping on the snow or ice when starting the vehicle or climbing. Preferably, the selection lever is movable between said first and second positions against the action of a return spring. Thus, said return spring can be arranged to return the selection lever to the first position, when the driver releases said lever. Therefore, the driver can decide at any time to release the gear lever so that the engine can apply its maximum torque on the drive wheels. The selection lever may be pivotally mounted between said first and second positions. Thus, this selection lever can be pivotally mounted along an axis transverse to the longitudinal axis of the vehicle, which allows the driver to move in an ergonomic manner. In one embodiment, the selection lever of the selection lever comprises a first branch for the movement of the lever between the position N and the position R, a second branch perpendicular to the first branch for the movement of the lever between the position N and the position D and a third branch perpendicular to the second leg for moving the lever between said first and second positions to vary the torque applied to the wheels between 100% and 0% of the maximum value. Preferably, the motor vehicle comprises an electronic control unit for the position of the accelerator pedal for controlling the torque applied to the wheels and the position of the speed lever, this unit being programmed to multiply the torque applied to the wheels by a factor between 1 and 0, when the selection lever is moved between said first and second positions. According to an advantageous feature of the invention, the selection lever comprises a display means visible by the driver when one of the drive wheels rotates at a higher speed than one of the non-driving wheels, according to a predetermined value. This display means may be a pictogram which illuminates, in case of slippage, to encourage the driver to move the selection lever to reduce the torque applied to the driving wheels. Other features and advantages of the invention will become apparent throughout the description below. In the accompanying drawings, given by way of nonlimiting example: FIG. 1 is a diagrammatic plan view of a motor vehicle equipped with an electric motor showing the various control means of the engine, FIG. top view of the gear selection lever and the gate thereof, the vehicle according to the invention, the lever being in the position N; - Figure 3 is a view similar to Figure 2, the lever being in the position R, - Figure 4 is a view similar to Figure 2 or 3, the lever being in the D position (100% of torque), - Figure 5 is a view similar to Figure 4, the lever being in the position D (0% of the torque), - Figures 6 and 7 are views similar to Figures 4 and 5, the lever being in an intermediate position between 0 and 100% of the torque, - Figure 8 is a side view of selection lever and a sectional view of the selection grid.

FIG. 1 schematically represents a motor vehicle equipped with an electric motor 1 powered by a battery 2. The electric motor 1 is directly coupled to the two rear wheels 3.

The reference 4 designates a power cable which connects the battery 2 to the electric motor 1 via an electronic control unit 5. The vehicle comprises a speed selection lever 6 which will be detailed later, a pedal accelerator 7 which allows the driver to vary the torque applied by the engine 1 on the drive wheels 3 and an electronic control unit 8 for controlling the position of the accelerator pedal 7 and the position of the speed selection lever 6. As shown in Figures 2 to 7, the speed selection lever allows the driver to select the following three positions: position N (neutral), - position R to roll back the vehicle, - position D to advance the vehicle . According to the invention, in the position D, the selection lever 6 is displaceable by the driver continuously, between a first position in which (see FIG. 4), the torque applied to the driving wheels of the vehicle is equal to 100 % of the maximum value and a second position in which (see Figure 5) the torque applied to these wheels is equal to 0%. Figures 6 and 7 show positions of the selection lever 6 intermediate between the two positions above. As indicated in FIG. 8, the selection lever 6 is movable between the first and second positions above against the action of a return spring 9. More precisely, the return spring 9 is arranged to recall the lever of selection 6 to the first position, that is to say that shown in Figure 4, when the driver releases the lever 6. In the example illustrated in Figure 8, the selection lever 6 is pivotally mounted between the first and second positions mentioned above, along an axis 10 transverse to the longitudinal axis X of the vehicle.

In the embodiment illustrated in FIGS. 2 to 7, the selection grid 11 of the selection lever 6 comprises a first branch 12 for the displacement of the lever 6 between the position N and the position R, a second branch 13 perpendicular to the first branch 12 for the movement of the lever 6 between the position N and the position D and a third branch 14 perpendicular to the second branch 13 for the movement of the lever 6 between the first and second positions, mentioned above, in order to vary the torque applied to the wheels 3 between 100% and 0% of the maximum value.

The control unit 8 shown in FIG. 1 controls the position of the accelerator pedal 7 controlling the torque applied to the wheels 3 and the position of the speed lever 6. This case 8 is programmed to multiply the torque applied to the wheels 3 by a factor of between 1 and 0, when the selection lever 6 is moved between the first and second positions, represented respectively in FIGS. 4 and 5. In the example shown in FIGS. 2 to 7, the selection grid 11 comprises display means such as a pictogram 15 which illuminates to warn the driver when one of the driving wheels 3 is rotating at a higher speed than one of the non-driving wheels, by a predetermined value. The device just described works as follows. When the electric vehicle is traveling on a non-slippery road, the selection lever is in the position D shown in FIG. 4. In this position, the torque delivered by the engine 1 is transmitted to the wheels 3 according to the position of the pedal. accelerator 7. This torque can reach 100% of the maximum torque. When the road is snowy or slippery and the lever 6 is in the position shown in Figure 4, the wheels 3 may slip, due to the sudden increase in the torque transmitted to these wheels.

In case of slippage of the driving wheels 3, the pictogram 15 lights up to induce the driver to reduce the torque delivered by the engine. For this purpose, it is sufficient to move the lever 6 to a position close to that indicated in FIG. 5. This displacement of the lever 6 has the effect of reducing the torque to a value between 100% and 0% of that of the torque maximum and therefore avoid wheel spinning 3.

The driver can then release the lever 6 so that it returns to the initial position shown in FIG. 4 and continue on its course, by dosing the torque applied to the wheels 3 only with the accelerator pedal 7. that described above can also be applied to vehicles equipped with a combustion engine coupled to a robotized gearbox which is devoid of a clutch whose control can be actuated by the driver. In this case, the fact of being able to reduce the torque exerted on the wheels by moving the speed selection lever makes it possible to prevent wheel spin when starting the vehicle on a slippery road.

Claims (8)

REVENDICATIONS1. Motor vehicle with an electric motor (1) or a combustion engine coupled to a robotised gearbox, comprising a speed selection lever (6) enabling the driver to select the following three positions: - position N (neutral), - position R for rearranging the vehicle, - position D to advance the vehicle, characterized in that, in the position D, the selection lever (6) is movable by the driver continuously, between a first position in which the torque applied on the driving wheels (3) of the vehicle is equal to 100% of the maximum value and a second position in which the torque applied to these wheels (3) is equal to 0%. 2. Motor vehicle according to claim 1, characterized in that the selection lever (6) is movable between said first and second positions against the action of a return spring (9). 3. Motor vehicle according to claim 2, characterized in that said return spring (9) is arranged to return the selection lever (6) to the first position, when the driver releases said lever (6). 4. Motor vehicle according to one of claims 1 to 3, characterized in that the selection lever (6) is pivotally mounted between said first and second positions. 5. Motor vehicle according to claim 4, characterized in that the selection lever (6) is pivotally mounted along an axis (10) transverse to the longitudinal axis (X) of the vehicle. 6. Motor vehicle according to one of claims 1 to 5, characterized in that the selection gate (11) of the selection lever (6) comprises a first leg (12) for the movement of the lever (6) between the position N and the position R, a second leg (13) perpendicular to the first leg (12) for the movement of the lever (6) between the N position and the D position and a third leg (14) perpendicular to the second leg (13). ) for moving the lever (6) between said first and second positions to vary the torque applied to the wheels between 100% and 0% of the maximum value. 7. Motor vehicle according to one of claims 1 to 6, characterized in that it comprises an electronic control unit (8) for controlling the position of the accelerator pedal (7) for controlling the torque applied to the wheels (3). ) and the position of the speed lever (6), this housing (8) being programmed to multiply the torque applied to the wheels (3) by a factor between 1 and 0, when the selection lever (6) is moved between said first and second positions. 8. Motor vehicle according to one of claims 1 to 7, characterized in that the selection lever (6) comprises a display means (15) visible by the driver when one of the drive wheels (3) rotates. a speed higher than one of the non-driving wheels, according to a predetermined value.