System intended to equip an electric vehicle comprising at least one sound generation module

Abstract

The invention relates to a system intended to equip an electric vehicle (1) comprising: - at least one sound generation module (2) configured to generate sound vibrations having at least one frequency and one amplitude; - a control unit (37) for controlling said sound generation module (2), said control unit (37) being configured to, at least in a sound generation mode: - receive a variable (38) representative of a rotation speed Vmot of an electric motor (9) of the electric vehicle (1) and a variable (39) representative of an acceleration setpoint Sacc of the electric vehicle (1);and - control the sound generation module (2) as a function of the variable (38) representative of the speed Vmot and the variable (39) representative of the acceleration setpoint Sacc so as to vary the frequency of the sound vibrations as a function of the variable (38) representative of the speed Vmot and the amplitude of the sound vibrations as a function of the variable (39) representative of the acceleration setpoint Sacc. Figure to be published: 13;

Description

Title of the invention: System intended to equip an electric vehicle comprising at least one sound generation module Technical field

[0001] The invention relates to the field of electric vehicles.

[0002] It relates more particularly to a system intended to equip an electric vehicle, such as a two-wheeled electric vehicle for example, and comprising a sound generation module, to an electric vehicle comprising such a system and to a method for controlling a sound generation module. Technological background

[0003] Without an audible warning system, electric vehicles are almost completely silent, which presents a danger to pedestrians, cyclists and more generally to all other road users. Thus, it is necessary to equip electric vehicles with audible warning devices.

[0004] Document EP2540600 discloses a two-wheeled electric vehicle equipped with such an audible warning device and proposes various embodiments thereof. Some do not require an electrical power supply and are based on the principle of Helmotz resonators or vibrating reeds. Others provide for the use of a loudspeaker.

[0005] However, these audible warning devices are not entirely satisfactory. Indeed, they do not allow the sound environment of a thermal vehicle, and in particular a motorcycle, to be reproduced in a credible manner. However, it proves particularly advantageous to have a sound generation device allowing the sound environment of a thermal vehicle to be reproduced as faithfully as possible both to guarantee the effectiveness of the alert function for other road users and to ensure better driving sensations, in particular by offering the driver a better sensory perception of the vehicle's driving conditions. Summary

[0006] An idea at the basis of the invention therefore consists of proposing a system intended to equip an electric vehicle and comprising a sound generation module for an electric vehicle which is particularly simple and is capable of reproducing more faithfully the sound environment of a thermal vehicle.

[0007] Thus, according to one embodiment, the invention provides a system intended to equip an electric vehicle comprising: - at least one sound generation module configured to generate sound vibrations having at least one frequency and one amplitude; - a control unit for controlling said sound generation module, said control unit being configured to, at least in a sound generation mode: - receive a variable representative of a rotation speed Vmot of an electric motor of the electric vehicle and a variable representative of an acceleration setpoint Sacc of the electric vehicle; and - control the sound generation module as a function of the variable representing the speed Vmot and the variable representing the acceleration setpoint Sacc so as to vary the frequency of the sound vibrations as a function of the variable representing the speed Vmot and the amplitude of the sound vibrations as a function of the variable representing the acceleration setpoint Sacc.

[0008] Thus, the control unit varies the frequency of the sound vibrations as a function of the engine speed and varies the amplitude of the sound vibrations as a function of the acceleration of the vehicle, which makes it possible to reproduce more faithfully the sound environment of a thermal vehicle while providing the driver with sensory indications on the driving conditions of the vehicle.

[0009] According to embodiments, such a system may comprise one or more of the following features.

[0010] According to one embodiment, the system comprising two sound generation modules configured to generate sound vibrations having at least one frequency and one amplitude, the control unit being configured to, at least in a particular operating mode of the electric vehicle, control the sound generation modules as a function of the variable representative of the speed Vmot and the variable representative of the acceleration setpoint Sacc in such a way that the frequency of the sound vibrations generated by one and the other of the two sound generation modules varies as a function of the variable representative of the speed Vmot and that the frequencies of the sound vibrations generated by the two sound emitting members have a difference of between 0 Hz, not included, and 30 Hz.

[0011] Such a difference in frequency between the vibrations generated by the two sound generation modules introduces a sound effect, called "beating", which makes it possible to inform the driver and / or other road users of a particular operating mode of the electric vehicle.

[0012] According to one embodiment, the or each sound generation module comprises: - an air circulation duct having an air intake inlet and an air exhaust outlet and configured to conduct an air flow in a flow direction and a flow direction oriented from the air intake inlet to the air exhaust outlet; and - a sound emission member which is pivotally mounted along a pivot axis intersecting the flow direction, said sound emission member comprising at least minus one edge; and - an actuator which is arranged to pivot said sound emitting member around the pivot axis so as to create flow disturbances in the air flow, generating the sound vibrations when the edge moves in the flow direction; the control unit being configured to: - determine a speed setpoint Vact as a function of said variable representative of the speed Vmot; and - control the actuator by means of said speed setpoint Vact.

[0013] Thus, the sound generated by such a sound generation module is more authentic because it is of mechanical and not synthetic origin. Such a sound emission member is therefore capable of faithfully reproducing the sound environment of a thermal vehicle.

[0014] Furthermore, for the same electrical power and a similar size to that of a loudspeaker, such a sound emitting member generates sound vibrations, without distortion and with a higher sound volume. This advantage is even more marked for low frequencies which have the longest range. The sound generation module of the aforementioned type therefore makes it possible to more effectively warn other road users of the arrival of the electric vehicle.

[0015] Furthermore, such a sound generation module is particularly simple, which ensures in particular a long service life and better resistance to vibrations at a lower cost.

[0016] Finally, electric vehicles of the state of the art generally comprise a cooling device equipped with a fan which generates sound vibrations and whose rotation speed is not controlled according to the driving conditions of the vehicle but according to the temperature of the components of the vehicle to be cooled. Therefore, in such a case, the sound vibrations generated by the fan are likely to mislead the driver or road users about the driving conditions of the electric vehicle. Thus, a sound generation module of the aforementioned type makes it possible to conceal or transform the sound vibrations generated by such a fan.

[0017] According to one embodiment, the sound emission member is housed inside the air circulation duct, is arranged opposite the air intake inlet or opposite the air intake inlet.

[0018] According to one embodiment, the value of the speed setpoint Vact is between a minimum value Vact_min and a maximum value Vact_max.

[0019] According to one embodiment, the value of the speed setpoint Vact is determined by means of at least one function Vact = fi(Vmot).

[0020] According to one embodiment, fl is a strictly increasing, linear or No.

[0021] According to one embodiment, the actuator is an electric motor configured to drive the sound emission member in rotation around said pivot axis.

[0022] According to one embodiment, the system comprises two sound generation modules configured to generate sound vibrations having at least one frequency and one amplitude and each comprising a sound emission member and an actuator arranged to pivot said sound emission member; the control unit being configured to, at least in a particular operating mode of the electric vehicle: - determine two speed setpoints Vacti and Vact2 for the actuator of one and the other of the two sound generation modules as a function of said variable representing the speed Vmot; and - controlling the actuator of one and the other of the two sound generation modules respectively by means of one and the other of two speed instructions Vacti and Vact2; the speed instructions Vacti and Vact2 having a difference such that a gap between the frequencies of the sound vibrations generated by the two sound emission members is between 0 Hz, not included, and 30 Hz.

[0023] According to one embodiment, the sound generation module comprises a flow control device which is housed in the air circulation duct and is configured to regulate the flow of air circulating inside the air circulation duct, and the control unit is configured to: - determine a Q deb instruction as a function of said variable representing the acceleration instruction Sacc; and - control the flow rate control device by means of said setpoint Q deb

[0024] According to one embodiment, the flow rate control device comprises a fan, said fan being controlled by means of said setpoint Q deb. Such a fan thus makes it possible to ensure a sufficient air flow to generate a sound, whatever the driving conditions, i.e. even when the vehicle is stationary. It also makes it possible to increase the amplitude of the sound vibrations generated.

[0025] According to one embodiment, the fan is an axial fan.

[0026] According to another embodiment, the fan is a radial fan.

[0027] According to one embodiment, the value of the setpoint Q deb is between a minimum value Q_deb_min and a maximum value Q_deb_max.

[0028] According to one embodiment, the value of the setpoint Q deb is determined by means of at least one function Q deb = f2 (Sacc) with Sacc: a positive or negative acceleration setpoint Vact>.

[0029] According to one embodiment, f2 is a strictly increasing function, linear or No.

[0030] According to one embodiment, the control unit has at least: - a sound generation mode in which the control unit controls the sound generation module as a function of the variable representing the speed Vmot and the variable representing the acceleration setpoint Sacc; and - a silent mode in which the control unit controls the sound generation module so as not to generate sound vibrations or to generate sound vibrations at frequencies inaudible to the human ear.

[0031] According to one embodiment, the control unit is configured to: - receive a variable representative of the operating mode of the sound generation module selected by the driver; and - activate silent mode when the value of said variable corresponds to a selection of silent mode by the driver.

[0032] According to one embodiment, the control unit is configured to: - receive a location variable containing information representative of a position of the electric vehicle; and - enable or disable silent mode based on the location variable.

[0033] According to one embodiment, the sound generation module comprises a fixing device suitable and intended for fixing said sound generation module to an electric vehicle. The sound generation module is therefore suitable for being mounted on the vehicle and for being dismantled, which in particular facilitates maintenance operations.

[0034] According to one embodiment, the fixing device is a reversible fixing device.

[0035] According to one embodiment, the air intake inlet is positioned on a front face of the sound generation module, said front face being intended to be directed towards the front of the electric vehicle. This promotes the admission of air into the air circulation duct under the effect of the movement of the vehicle.

[0036] According to one embodiment, the air intake inlet has a section which decreases according to the direction of flow.

[0037] According to another embodiment, the air intake inlet is positioned on an external lateral face of the sound generation module, said external lateral face being intended to be directed laterally towards the outside of the electric vehicle. The air flow circulating in the air circulation duct is thus decorrelated from the speed of the electric vehicle.

[0038] According to one embodiment, the module comprises a fairing and at least a portion of the air circulation duct and the actuator are housed inside the fairing. The fairing thus makes it possible to protect the actuator as well as at least a portion of the air circulation duct duct and in particular that equipped with the emission member. sound.

[0039] According to one embodiment, the invention also provides an electric vehicle comprising a system of the aforementioned type.

[0040] According to embodiments, such an electric vehicle may comprise one or more of the following characteristics.

[0041] According to one embodiment, the electric vehicle is a vehicle intended to be ridden, for example, an electric motorcycle.

[0042] According to one embodiment, the electric vehicle comprises a frame and the sound generation module is fixed to said frame.

[0043] According to one embodiment, the system comprises two sound generation modules fixed to the frame, laterally on either side of said frame.

[0044] According to one embodiment, the air exhaust outlet of the sound generation module is directed towards one or more components of the electric vehicle selected from an electric motor, an electrical energy storage unit, a controller, one or more electronic cards, interconnection bars, a reducer, a gearbox and an air / liquid heat exchanger. In general, the exhaust outlet can be directed towards any component of the electric vehicle generating thermal energy.

[0045] Therefore, the sound generation module has a dual functionality since it allows, in addition to its sound generation function, to provide a thermal cooling function.

[0046] According to one embodiment, the electric vehicle comprises an air / liquid heat exchanger which is housed inside the air circulation duct, is positioned opposite the air exhaust outlet or opposite the air intake inlet.

[0047] Finally, according to another aspect, the invention also relates to a method for controlling at least one sound generation module intended for an electric vehicle; said sound generation module being configured to generate sound vibrations having at least one frequency and one amplitude, said method comprising the following steps: - receive a variable representative of a rotation speed Vmot of an electric motor of the electric vehicle and a variable representative of an acceleration setpoint Sacc of the electric vehicle; - control the sound generation module as a function of the variable representing the speed Vmot and the variable representing the acceleration setpoint Sacc so as to vary the frequency of the sound vibrations as a function of the variable representing the speed Vmot and the amplitude of the sound vibrations as a function of the variable representing the acceleration setpoint Sacc.

[0048] According to one embodiment, the control method is implemented to control two sound generation modules having a frequency and a sound volume, and the two sound generation modules are controlled as a function of the variable representing the speed Vmot and the variable representing the acceleration setpoint Sacc in such a way that the frequencies of the sound vibrations generated by the two sound emission members have a difference of between 0 Hz, not included, and 30 Hz. Brief description of the figures

[0049] The invention will be better understood, and other aims, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes, with reference to the appended drawings.

[0050] [Fig-1] [Fig. 1] is a partial front view of an electric motorcycle comprising two sound generation modules, according to a first embodiment, arranged laterally on either side of the electric motorcycle.

[0051] [Fig.2] [Fig.2] is a partial, perspective, three-quarter front view of the electric motorcycle of [Fig.l].

[0052] [Fig.3] [Fig.3] is a partial, side view of the electric motorcycle of [Fig.l].

[0053] [Fig.4] [Fig.4] is a sectional view of one of the sound generation modules re presented in Figures 1 to 3.

[0054] [Fig.5] [Fig.5] is a perspective view of the sound generation module, which is positioned on the left side of the electric motorcycle shown in figures 1 to 3 and representing its attachment device to the frame of the electric motorcycle.

[0055] [Fig.6] [Fig.6] is a detailed view of the sound emission organ of the module of sound generation of [Fig.4].

[0056] [Fig.7] [Fig.7] represents, by way of example, six other variant embodiments of the sound-emitting organ.

[0057] [Fig.8] [Fig.8] is a partial, side view of an electric motorcycle equipped with sound generation modules according to a second embodiment.

[0058] [Fig.9] [Fig.9] is a perspective view of the sound generation module which is positioned on the left side of the electric motorcycle shown in [Fig.8], and representing in particular its air exhaust outlets and its attachment device to the frame of the electric motorcycle.

[0059] [Fig. 10] [Fig. 10] is a schematic sectional view of the sound generation module according to the second embodiment shown in Figures 8 and 9.

[0060] [Fig. 11] [Fig. 11] is a schematic representation of the principle of sound generation by a sound-emitting member which is rotated around a pi- axis voting.

[0061] [Fig. 12] [Fig. 12] is a schematic representation of the principle of sound generation by a sound-emitting member which oscillates around an equilibrium position by pivoting around a pivot axis.

[0062] [Fig. 13] [Fig. 13] is a schematic representation of a control unit for controlling a sound generation module. Description of the embodiments

[0063] By convention, the term electric vehicle, within the meaning of this document, is understood to mean: - a vehicle with exclusively electric propulsion, i.e. whose propulsion is ensured solely by means of one or more electric motors; or - a hybrid propulsion vehicle having at least one operating mode in which propulsion is provided solely by means of one or more electric motors.

[0064] Although the invention can be used for any type of electric vehicle, it is more particularly intended for an electric vehicle intended to be ridden by its driver, for example a two-wheeled electric vehicle, such as an electric motorcycle.

[0065] With reference to Figures 1 to 3, an electric motorcycle 1 equipped with sound generation modules 2 according to a first embodiment is described below. The electric motorcycle 1 comprises, in particular, two wheels 3, 4, one at the front and the other at the rear, a frame 5, a fork 6 pivotally mounted on the frame 5 and connecting the front wheel 3 to the frame 5 as well as a handlebar 7 secured to the fork 6. The electric motorcycle 1 also comprises an electrical energy storage unit, such as a battery 8, an electric motor 9 connected to the electrical energy storage unit 8 and a transmission system 10 coupling the electric motor 9 to the rear wheel 4.

[0066] Several control devices, not shown, such as a pedal or accelerator handle and a brake, are connected to a controller 11 which is connected to the battery 8 and to the electric motor 9. According to an advantageous embodiment, the controller 11 as well as the control devices and the various sensors equipping the electric motorcycle 1 are connected to each other by a bus, for example of the CAN type. The controller 11 is configured to control the electric motor 9 according to the setpoint signals delivered by the control devices and in particular according to an acceleration setpoint. According to one embodiment, the controller 11 is also configured to implement regenerative braking, that is to say to control the electric motor 9 so that it exerts a resistive torque and thus acts as an electric generator, when the brake is actuated and consequently the acceleration setpoint is negative.

[0067] The electric motorcycle 1 comprises two sound generation modules 2 which are fixed to the frame 5, laterally on either side thereof. Note however that, in other embodiments, not shown, the electric vehicle may comprise only one sound generation module 2 or even more than two. The sound generation modules 2 may also be placed in any other position than those shown in FIGS. 1 to 3.

[0068] Figures 4 and 5 represent one of the sound generation modules 2 equipping the electric motorcycle of Figures 1 to 3. The sound generation module 2 comprises a fairing 12 inside which is housed, at least partially, an air circulation duct 13. The air circulation duct 13 has an air intake inlet 14 and an air exhaust outlet 15. The air circulation duct 13 makes it possible to conduct an air flow in a direction and a flow direction, shown diagrammatically by the arrow referenced F1 in [Fig.4]. In this embodiment, the air intake inlet 14 is positioned on the front face of the sound generation module 2, i.e. on a face directed towards the front of the electric motorcycle 1 when the sound generation module 2 is fixed to the frame 5. This arrangement is advantageous in that it promotes the admission of air into the air circulation duct 13 under the effect of the movement of the electric motorcycle 1.The air intake inlet 14 advantageously has a convergent shape, that is to say that its section decreases in the direction of air flow.

[0069] Advantageously, the sound generation module 2 further comprises a flow rate control device which is configured to control the flow rate of air circulating inside the air circulation duct 13. In the embodiment shown, the flow rate control device comprises a fan 18 for ensuring forced air circulation in the air circulation duct 13. Such a fan 18 proves to be particularly advantageous in that it makes it possible to ensure a sufficient air flow rate to generate a sound, even when the electric motorcycle is stationary and in that it makes it possible to act on the amplitude of the sound vibrations, as will be explained later. The fan 18 is here of the axial type, that is to say that it sucks in and discharges the air parallel to its axis of rotation.

[0070] Alternatively or additionally, according to another embodiment not shown, the flow rate regulation device comprises a flow rate regulation valve.

[0071] Furthermore, the sound generation module 2 comprises a sound emission member 17 which is shown in detail in [Fig. 6]. The sound emission member 17 is pivotally mounted along a pivot axis X which is intersecting, and preferably perpendicular, to the flow direction. The sound emission member 17 is here housed inside the air circulation duct 13. However, according to other embodiments lisation not illustrated, the sound emission member 17 may have another positioning, for example opposite the air intake inlet 14 or opposite the air exhaust outlet 15, as long as this positioning allows it to be placed in the air flow.

[0072] The sound emission member 17, which is shown in detail in [Fig. 6], has a disc shape whose section is slightly smaller than that of the corresponding section of the air circulation duct 13. The sound emission member 17 here has two edges 19, 20, arranged on either side of the pivot axis X and each connecting the two circular faces of the disc. The sound generation module 2 also comprises an actuator which is housed inside the fairing 12 and is arranged to pivot the sound emission member 17 around the aforementioned pivot axis X. In the embodiment shown, the actuator is an electric motor 21 which makes it possible to drive the sound emission member 17 in rotation around said pivot axis X. Advantageously, the sound generation module 2 further comprises an encoder 22 coupled in rotation to the electric motor 21 or to the sound emission member 17.The encoder 22 thus delivers a signal representative of the relative position of the sound emission member 17. The encoder 22 is also housed inside the fairing 12.

[0073] The operating principle of such a sound emitting member 17 is explained in relation to [Fig. 11]. When the sound emitting member 17 is rotated about the axis X, the two edges 19, 20 move alternately, in the direction of flow (corresponding to the direction of the arrow F1), and in the opposite direction. Each time an edge moves in the direction of flow (the one referenced 20 in [Fig. 11]), it is in a leaky state. As soon as an edge 19, 20 is in a leaky state, it generates disturbances in the flow, through the air circulation duct 13, and more particularly Van Karman vortices. Such disturbances have the effect of generating sound vibrations whose frequency depends on the speed of rotation of the sound emitting member 17 and the number of edges 19, 20 which it comprises.The amplitude of the sound vibrations depends on the air flow circulating in the air circulation duct 13.

[0074] According to an alternative embodiment, illustrated in [Fig. 12], the sound emitting member 17 does not perform a complete rotation around the pivot axis X but oscillates on either side of an equilibrium position, shown in dotted lines in [Fig. 12]. Thus, the edge 19 of the sound emitting member 17 generates sound vibrations: - when it moves over a first angular range al, arranged on one side of the equilibrium position, in a first direction, represented by the arrow F2 corresponding to a movement of the edge 19 in the flow direction Fl; and - when it moves in a second angular range a2, arranged on the other side of the equilibrium position, in a second direction, represented by the arrow F3, opposite to the first, and also corresponding to a displacement of the edge 19 in the direction of flow Fl.

[0075] Returning to Figures 2 to 5, it can be seen that the air circulation duct 13 comprises, downstream of the sound emission member 17, an optional outlet director portion 23, which projects from the fairing 12 and which thus makes it possible to position the air exhaust outlet 15 opposite one or more components to be cooled of the electric motorcycle 1, i.e. the temperature of which must be maintained below a threshold. Thus, the sound generation module 2 has a dual functionality since it makes it possible, in addition to its sound generation function, to ensure cooling of one or more components of the electric motorcycle 1. In addition, the activity of the fan 18 is likely to benefit simultaneously the two aforementioned functions, which makes it possible to further improve the overall energy efficiency.

[0076] Advantageously, the air exhaust outlet 15 is directed towards one or more components of the electric vehicle chosen from: the electric motor 9, an electrical energy storage unit, the controller 11, one or more electronic cards, interconnection bars, a reducer and a gearbox. For example, in [Fig.4], the air exhaust outlet 15 is directed opposite the electric motor 9.

[0077] In an alternative or complementary embodiment, not shown, the electric motorcycle 1 comprises an air / liquid heat exchanger which is connected to a hydraulic cooling circuit, equipped with a pump, and making it possible to ensure cooling of the aforementioned components of the electric vehicle. The air / liquid heat exchanger is housed inside the air circulation duct 13, is positioned opposite the air exhaust outlet 15 or even opposite the air intake inlet 14.

[0078] Furthermore, each of the sound generation modules 2 comprises a fixing device 24, an exemplary embodiment of which is partially shown in [Fig. 5]. The fixing device 24 is intended to ensure the fixing of said sound generation module 2 to the frame 5 of the electric motorcycle 1. Advantageously, the fixing device 24 is a reversible fixing device. It is thus possible to easily mount and dismount the sound generation modules 2, in particular for maintenance or replacement purposes. In the embodiment shown, the fixing device 24 comprises, on the side of the frame 5 of the electric motorcycle 1, two retaining pins 25, and, on the side of the sound generation module 2, two receiving cradles 26 which are each intended to receive one of the two retaining pins 25 when the sound generation module 2 is fixed to the frame 5 of the electric motorcycle 1. As an example, patent application EP2779868 discloses examples of retaining pins 25 and receiving cradles 26, capable of being used for such an application.

[0079] Furthermore, the fixing device 24 also comprises, on the side of the frame 5 of the electric motorcycle 1, a V-lock type locking device 27 comprising a V-shaped female element, and on the side of the sound generation module 2, a male element, not visible, also V-shaped, which is received in the female element when the sound generation module 2 is fixed to the frame of the electric motorcycle 1. The locking device also comprises, on the side of the frame 5 of the electric motorcycle 1, a movable bolt, not visible, which is capable of assuming a locked state in which it engages in a housing of the male element in order to lock the male and female elements to each other. The locking device further comprises an unlocking button 44 which is associated with a mechanism of the locking device and is thus capable of moving the movable bolt to an unlocking position when said locking button 44 is actuated.Note that the aforementioned fixing device is described above only as an example. It is thus possible to reverse the arrangement of the aforementioned elements, that is to say to fix the female element and the receiving cradles on the side of the frame of the electric motorcycle 1 and the male element and the retaining pins 25 on the side of the sound generation module 2 or even to use any other type of fixing device.

[0080] [Fig.7] illustrates different variants of sound emission members 17 that may be used. It can thus be observed that the shape of the sound emission member 17 is likely to vary significantly, as long as it has at least one edge 19, 20 on its periphery. Thus, the sound emission member 17 may extend only in one plane like that of [Fig.6] but may have an alternative shape, to that of a disc, for example, a rectangular shape (case a) or a triangular shape (case b). The sound emission member 17 may also extend in a multitude of planes and thus have numerous edges 19, 20 (case c). This makes it possible, for the same rotation speed of said sound emission member 17, to increase the frequency of the sound vibrations.The sound emission member 17 may also comprise several portions 28, 29, positioned one above the other and extending along two planes intersecting one another (case d), which also makes it possible to increase the frequency of the sound vibrations. Finally, it is also possible to use sound emission members 17 having complex shapes, inscribed in a sphere, and the edges 19, 20 of which do not extend in planes including the pivot axis (cases e and f).

[0081] Figures 8 to 10 illustrate sound generation modules 2 according to a second embodiment. As in the previous embodiment, each sound generation module 2 comprises an air circulation duct 13 and an inlet air intake. However, the air intake inlet 14 is not positioned on the front face of the sound generation module 2 but on an external lateral face, i.e. directed laterally towards the outside of the electric motorcycle 1. Such an arrangement makes it possible in particular to decorrelate the air flow circulating in the air circulation duct 13 from the speed of the electric motorcycle 1.

[0082] Furthermore, the flow control device comprises a radial type fan 18, also referred to as a “centrifugal fan”, i.e. it sucks in air axially and discharges it radially relative to its axis of rotation. Such a radial type fan 18 makes it possible to achieve higher pressures than an axial fan, such as that of the first embodiment.

[0083] The air circulation duct 13 comprises a Y-shaped portion which divides it into two branches 30, 31 each leading towards a respective air exhaust outlet 32, 33. One of the branches 31 comprises a flow regulating member 34 which makes it possible to vary the distribution of the air flow between the two branches 30, 31. The presence of several air exhaust outlets 32, 33 makes it possible to direct the outgoing air flow onto several components to be cooled and / or onto several different zones of the same component. In the embodiment shown in [Fig. 8], the air exhaust outlets 32, 33 are directed towards the battery 8.

[0084] Furthermore, the sound generation module 2 comprises several sound emission members 17, 35, 36, for example three in the embodiment shown. They may in particular have different shapes, which makes it possible in particular to generate a more complex sound environment. This also makes it possible to act on the sound volume generated by setting more sound emission members in motion to increase it or, on the contrary, by reducing their number to reduce it. This can also be used to transmit to the driver or other road users even more sensory information about the driving conditions of the vehicle.

[0085] In relation to [Fig. 13], a control unit 37 is described for controlling a sound generation module 2, as described above. Such a control unit 37 can be distributed indifferently on each of the sound generation modules 2 or even be centralized on the electric vehicle or on only one of the sound generation modules 2. Any other combination is also possible. Thus, the control unit 37 can in particular be distributed on the electric vehicle 1 and on each of the sound generation modules 2.

[0086] The control unit 37 is configured to control: - the flow regulating member(s), i.e. the fan 18 in the embodiments described above; - the actuator(s) enabling the sound emission member(s) 17, 35, 36 to be moved, i.e. the electric motor 21 for the embodiments described above. above; and - optionally, the flow regulating member 34 to vary the distribution of the flow between two branches 30, 31, in the event that the sound generation module 2 is equipped with it.

[0087] The control unit 37 is connected by a bus to the sensors and control equipment of the electric vehicle. The bus is, for example, of the CAN type, or uses any other communication protocol.

[0088] Thus, the control unit 37 receives at least the following variables: - a variable 38 representative of the speed Vmot of rotation of the electric motor 9; and - a variable 39 representative of the Sacc acceleration instruction of the electric vehicle.

[0089] The variable 38 can be acquired by means of a sensor mounted on the electric motor 9, on one of the wheels 3, 4 or at any location in the transmission chain between the electric motor 9 and the wheels 4.

[0090] Furthermore, according to advantageous embodiments, the control unit 37 receives one or more of the following variables: - a variable 40 representative of a regenerative braking instruction; - a variable 41 representative of the operating mode of the sound generation modules 2; - a variable 42 representative of the operating mode of the electric vehicle; and - a location variable 43 containing information representative of the position of the electric vehicle.

[0091] The control unit 37 controls the actuator of each of the sound generation modules 2, i.e. the electric motor 21, by means of a speed setpoint Vact. In at least one sound generation mode of the sound generation module 2 and a driving mode of the electric vehicle, the speed setpoint Vact is determined as a function of the variable 38 representative of the rotation speed Vmot of the electric motor 9.

[0092] More particularly, the value of the speed setpoint Vact is between a minimum value Vact_min and a maximum value Vact_max and is determined by means of at least one function Vact = fi(Vmot). According to embodiments, fl is a strictly increasing function, linear or not. According to other embodiments, fl may be a sawtooth function comprising a plurality of strictly increasing portions connected by decreasing portions, which makes it possible in particular to simulate gearbox ratio changes.

[0093] According to one embodiment, the control unit 37 determines the value V_Sact of the reference signal Sact by means of two functions Vact = fi(Vmot) and Vact = fi(Vmot), one of which is used when the speed Vmot increases and the other when it decreases.

[0094] The control unit 37 controls the electric motor 21, in a closed loop, as a function of the speed setpoint Vact and the signal delivered by the encoder 22.

[0095] According to one embodiment, the value V_Sact can be determined as a function of the speed Vmot and one or more other variables, such as the acceleration setpoint q ^acc*

[0096] According to one embodiment, the value V_Sact can be determined as a function of the speed Vmot and one or more other variables, such as the acceleration setpoint q ^acc*

[0097] Furthermore, for the sound generation mode of the sound generation module 2 and the driving mode of the electric vehicle, the control unit 37 controls the flow rate regulating member of each of the sound generation modules 2, i.e. the fan 24, by means of a setpoint Q deb. The setpoint Q deb is determined as a function of the variable 39 representative of the acceleration setpoint Sacc of the electric vehicle.

[0098] The setpoint Q deb is between a minimum value Q_deb_min and a maximum value Q_deb_max and is determined by means of at least one function Q deb = f2 (S acc) with Sacc: a positive or negative acceleration setpoint, i.e. corresponding to a deceleration. According to embodiments, f2 is a strictly increasing function, linear or not. f2 can also be a sawtooth function.

[0099] According to one embodiment, the control unit 37 determines the setpoint Q deb by means of two functions Q deb = f2 (Sacc) and Q deb = f'2 (Sacc), with f2 and f'2 increasing functions, one of which is used for positive acceleration setpoints and the other for negative acceleration setpoints, i.e. decelerations.

[0100] According to embodiments, in particular when the air intake inlet 14 is positioned on the front face so that the air flow circulating in the air circulation duct 13 depends on the speed of the vehicle, the flow setpoint Q debest is determined both as a function of the speed of the electric vehicle, and more particularly of the variable 38 representative of the rotation speed Vmot of the electric motor 9, and as a function of the acceleration setpoint Sacc. This makes it possible to take into account the air flow admitted into the air circulation duct 13 due to the movement of the electric vehicle.

[0101] Furthermore, according to one embodiment, in at least one particular operating mode of the electric vehicle, the control unit 37 is configured to deliver to two actuators moving two different sound emission members 17, 35, 36 different speed setpoints Vacti and V^. More particularly, the difference between the speed instructions Vacti and Vact2 is such that the difference between the frequencies of the sound vibrations generated by the two sound emitting members 17, 35, 36 is between 0 Hz (terminal not included) and 30 Hz. Thus, such a difference introduces a sound effect, called "beating", which makes it possible to inform the driver and / or other road users of the particular operating mode of the electric vehicle. According to an advantageous embodiment, such a beating effect is generated as a function of the variable 40 representative of a regenerative braking instruction, and more particularly when regenerative braking is implemented by the controller 11 of the electric vehicle. Note that the two sound emitting members 17, 35, 36 generating such a beating effect can indifferently belong to two different sound generation modules 2 or even belong to the same sound generation module 2.

[0102] According to one embodiment, the control unit 37 has at least two operating modes of the sound generation modules 2, namely at least: - a sound generation mode in which said control unit 37 controls the actuator associated with the sound emission member 17 and the flow rate regulation member of each of the sound generation modules 2 as described previously; and - a silent mode in which the sound emitting member(s) 17 do not generate sound vibrations or at least not at frequencies audible to the human ear.

[0103] Several variants of implementation of the silent mode are possible.

[0104] According to a first variant embodiment, in the silent mode, the actuator associated with the sound emission member 17 is no longer supplied with energy so that the sound emission member 17 is free to pivot around the pivot axis X.

[0105] According to a second variant embodiment, in said silent mode, the control unit 37 controls the actuator according to a position setpoint. In this case, the position of the sound emitting member 17 is fixed, in the silent mode. Advantageously, the position of the sound emitting member 17 corresponding to the aforementioned position setpoint corresponds to that in which the sound emitting member 17 generates the least pressure loss. Therefore, for the sound emitting member 17 described in relation to [Fig. 6], the position setpoint corresponds to an orientation of the plane of the disk which is parallel to the flow direction.

[0106] Finally, according to a third variant embodiment, in said silent mode, the control unit 37 controls the actuator at a constant speed in order to allow the flow of air through the air circulation duct, this speed preferably being sufficiently low so that the frequency of the vibrations generated is below the audible frequency range, i.e. below 20 Hz.

[0107] In such a silent mode, the fan 18 remains active in order to ensure the function of cooling of the electric vehicle equipment. Thus, the flow rate setpoint Q_deb is no longer determined according to the variable 39 representing the acceleration setpoint Sacc of the electric vehicle but according to one or more parameters representative of the temperature of the equipment to be cooled.

[0108] According to one embodiment, the silent mode is one of the operating modes of the sound generation modules 2 which is capable of being selected by the driver. Thus, the control unit 37 activates this silent mode when the value of the variable 41 representative of the operating mode of the sound generation modules 2 corresponds to a selection of the silent mode.

[0109] According to an alternative or complementary embodiment, the control unit 37 is configured to activate or deactivate the silent mode depending on the location variable 43.

[0110] According to one embodiment, the location variable 43 comprises coordinates representative of the position of the electric vehicle in the terrestrial reference frame. In this case, the control unit 37 determines the active or inactive state of the silent mode by means of a remote or local database establishing a relationship between position coordinates in the terrestrial reference frame and the active or inactive state of the silent mode.

[0111] According to another embodiment, the electric vehicle comprises one or more spatial detection sensors, chosen from cameras, LIDARS, radars and ultrasonic sensors and a signal processing unit configured to process the signals collected by the spatial position sensor(s) and assign to the location variable 43 a value representative of the position and / or the nature of the objects in the environment of the vehicle. For example, the processing unit can be configured to identify an urban area so that the control unit activates the silent mode, in an urban area, for example during the night. In such a case, the electric vehicle 1 comprises a clock.

[0112] According to one embodiment, the silent mode is also activated as a function of the variable 42 representative of the operating mode of the electric vehicle. Thus, the control unit 37 can be configured to activate the silent mode as a function of the value of the variable 42 representative of the operating mode of the electric vehicle, for example when the latter corresponds to a mode of recharging the battery 8.

[0113] According to an alternative embodiment, the control unit 37 is configured to control the sound generation modules 2 so that they produce a specific sound for an operating mode of the electric vehicle, for example when it is in the battery 8 recharging mode.

[0114] Furthermore, when the sound generation modules 2 are equipped with two branches each leading to an air exhaust outlet 32, 33, one of which is equipped with a sound emission member 36 and a flow regulation member 34 which makes it possible to vary the distribution of the air flow between the two branches 30, 31, as in the embodiment described above in relation to [Fig. 10], said flow regulation member 34 can be controlled by the control unit 37 as a function of the variable 39 representative of the acceleration setpoint Sacc of the electric vehicle.

[0115] By way of example, the control unit 37 can be configured to control the flow regulating member 34 so as to: - increase the air flow in the branch in question, and consequently the sound volume generated by the sound emitting member 36 when the acceleration setpoint Sacc increases; or - on the contrary, reduce the air flow when the Sacc acceleration setpoint decreases.

[0116] Some elements represented, in particular the control unit, can be produced in different forms, in a unitary or distributed manner, by means of hardware and / or software components. Usable hardware components are specific ASIC integrated circuits, FPGA programmable logic networks or microprocessors. Software components can be written in different programming languages, for example C, C++, Java or VHDL. This list is not exhaustive.

[0117] Although the invention has been described in connection with several particular embodiments, it is quite obvious that it is in no way limited thereto and that it includes all the technical equivalents of the means described as well as their combinations if these fall within the scope of the invention, as defined by the claims.

[0118] The use of the verb “comprise”, “comprendre” or “include” and its conjugated forms does not exclude the presence of other elements or other steps than those stated in a claim.

[0119] In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

Claims

Claims

1. System intended to equip an electric vehicle (1) comprising: - two sound generation modules (2) configured to generate sound vibrations having at least one frequency and one amplitude; - a control unit (37) for controlling said sound generation module (2), said control unit (37) being configured to, at least in one sound generation mode: - receive a variable (38) representative of a rotation speed Vmot of an electric motor (9) of the electric vehicle (1) and a variable (39) representative of an acceleration setpoint Sacc of the electric vehicle (1); and - controlling the sound generation modules (2) as a function of the variable (38) representative of the speed Vmot and the variable (39) representative of the acceleration setpoint Sacc so as to vary the frequency of the sound vibrations as a function of the variable (38) representative of the speed Vmot and the amplitude of the sound vibrations as a function of the variable (39) representative of the acceleration setpoint Sacc;said control unit being further configured to, at least in a particular operating mode of the electric vehicle (1), control the sound generation modules (2) as a function of the variable (38) representative of the speed Vmot and of the variable (39) representative of the acceleration setpoint Sacc in such a way that the frequency of the sound vibrations generated by one and the other of the two sound generation modules (2) varies as a function of the variable (38) representative of the speed Vmot and that the frequencies of the sound vibrations generated by the two sound emitting members have a difference of between 0 Hz, not included, and 30 Hz to produce a beating effect.;

2. System according to claim 1, wherein each sound generation module (2) comprises: - an air circulation duct (13) having an air intake inlet (14) and an air exhaust outlet (15) and configured to conduct an air flow in a flow direction and a flow direction (Fl) oriented from the air intake inlet (14) to the air exhaust outlet (15); and - a sound emission member (17) which is pivotally mounted about a pivot axis (X) intersecting the flow direction, said member sound emission member (17) comprising at least one edge (19, 20); and - an actuator which is arranged to pivot said sound emission member (17) around the pivot axis (X) so as to create flow disturbances in the air flow, generating the sound vibrations when the edge (19, 20) moves in the flow direction (Fl) and in which the control unit (37) is configured to: - determine a speed setpoint Vact as a function of said variable (38) representative of the speed Vmot; and - control the actuator by means of said speed setpoint Vact.

3. System according to claim 2, in which the actuator is an electric motor (21) configured to drive the sound emitting member (17) in rotation around said pivot axis (X).

4. System according to claim 3, wherein the control unit (37) is configured to, at least in the particular operating mode of the electric vehicle (1): - determine two speed setpoints Vacti and Vact2 for the actuator of one and the other of the two sound generation modules as a function of said variable (38) representative of the speed Vmot; and - control the actuator of one and the other of the two sound generation modules respectively by means of one and the other of two speed setpoints Vacti and Vact2; the speed setpoints Vacti and Vact2 having a difference such that a gap between the frequencies of the sound vibrations generated by the two sound emission members is between 0, not included, and 30 Hz.

5. System according to any one of claims 2 to 4, wherein the sound generation module (2) comprises a flow control device which is housed in the air circulation duct (13) and is configured to regulate the flow of air circulating inside the air circulation duct (13), and wherein the control unit (37) is configured to: - determine a setpoint Q deb as a function of said variable (38) representative of the acceleration setpoint Sacc; and - control the flow control device by means of said setpoint Q deb

6. The system of claim 5, wherein the flow rate control device comprises a fan (18) and wherein said fan is controlled by means of said setpoint Q deb.

7. A system according to any one of claims 1 to 6, wherein the control unit (37) has at least: - a sound generation mode in which the control unit (37) controls the sound generation module (2) as a function of the variable (38) representative of the speed Vmot and of the variable (39) representative of the acceleration setpoint Sacc; and - a silent mode in which the control unit (37) controls the sound generation module (2) so as not to generate sound vibrations or to generate sound vibrations at frequencies inaudible to the human ear.

8. System according to claim 7, wherein the control unit (37) is configured to: - receive a variable (41) representative of the operating mode of the sound generation module (2) selected by the driver; and - activate the silent mode when the value of said variable (41) corresponds to a selection of the silent mode by the driver.

9. System according to claim 7 or 8, wherein the control unit (37) is configured to: - receive a location variable (43) containing information representative of a position of the electric vehicle (1); and - activate or deactivate the silent mode depending on the location variable (43).

10. An electric vehicle (1) comprising a system according to any one of claims 1 to 9.

11. An electric vehicle (1) according to claim 10, wherein the electric vehicle (1) is a ride-on vehicle.

12. Method for controlling two sound generation modules (2) intended for an electric vehicle (1); said sound generation modules (2) being configured to generate sound vibrations having at least one frequency and one amplitude, said method comprising the following steps: - receiving a variable (38) representative of a rotation speed Vmot of an electric motor (9) of the electric vehicle (1) and a variable (39) representative of an acceleration setpoint Sacc of the electric vehicle (1); - controlling the sound generation modules (2) as a function of the variable (38) representative of the speed Vmot and of the variable (39) representative of the acceleration setpoint Sacc so as to vary the frequency of the sound vibrations as a function of the variable (38) represent- representative of the speed Vmot and the amplitude of the sound vibrations as a function of the variable (39) representative of the acceleration setpoint Sacc; the two sound generation modules (2) being controlled as a function of the variable (38) representative of the speed Vmot and of the variable (39) representative of the acceleration setpoint Sacc in such a way that the frequencies of the sound vibrations generated by the two sound emitting members have a difference between 0 Hz, not included, and 30 Hz.

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