Two-speed electric vehicle transmission device

Abstract

Transmission device for electric vehicle with two gear ratios The invention relates to a device (1) essentially comprising a rotational movement input stage (5), with an input shaft (5') kinematically connected to the electric motor (2) of the vehicle concerned, an intermediate torque transmission stage (6) comprising an intermediate shaft (6') and a rotational movement output stage (7), with a member (7') kinematically connected to at least one pair of wheels (4) to be driven.The input stage (5) is configured to provide selective torque transmission and for this purpose comprises at least one coupling member (10) which can be switched in a controlled manner between two positions or two states, for example by translational movement along the axis of rotation (AE) of this stage, and at least one clutch (11) which is configured to selectively establish a rotational securing connection between a toothed wheel (8'), mounted freely in rotation on the input shaft (5'), and this shaft (5'), this connection being complementary to that which can be established by the at least one coupling member (10). Figure to be published with the abstract: Fig. 1A.

Description

Title of the invention: Transmission device for electric vehicle with two speed ratios

[0001] The present invention relates to the field of transmission of movement in a vehicle between the engine and the wheels of the latter, and has as its subject a transmission device for an electric vehicle with two speed ratios, an axle integrating this device, as well as a vehicle equipped with such a device and such an axle.

[0002] Transmission devices for vehicles with internal combustion engines or for hybrid vehicles are well known. They generally have a relatively complex construction because, in connection with thermal propulsion, they must provide at least three or four gears and ensure gear changing possibilities. In the case of a hybrid vehicle, it is also necessary to allow switching between operation in thermal mode and operation in electric mode.

[0003] For electric vehicles, the transmission device is most often limited to a permanent kinematic chain, of the geared assembly type with speed reduction, between the motor and the wheels, the variation in speed of the motor making it possible to vary the forward speed of the vehicle and the inversion of the power supply making it possible to have a reverse gear.

[0004] There is, however, a demand in relation to electric vehicles for high output torque (transmitted to the wheels) and high maximum speed.

[0005] However, these two requirements are fundamentally contradictory with regard to the operating mode and performance of electrical machines. Indeed, a maximum output torque implies a minimum reduction ratio (therefore a maximum reduction in the rotational speed between the motor output and the wheel drive), whereas a maximum speed implies a maximum reduction ratio (therefore a minimum reduction, or even an increase, in the rotational speed between the motor output and the wheel drive).

[0006] Furthermore, there is also a demand to be able to kinematically disconnect the electric motor from the vehicle wheels.

[0007] The present invention aims to respond at least to the first, and preferably also to the second, aforementioned request(s), by advantageously proposing a solution with optimal efficiency, in particular in permanent mode, simple and economical, and substantially without interruption of torque during variations / changes of speed.

[0008] This object is achieved by the invention thanks to a transmission device for a vehicle electric, providing a torque transmission path by meshing, between the engine of said vehicle and at least one of its wheels,

[0009] this device essentially comprising a rotational movement input stage, with an input shaft kinematically connected to the electric motor of the vehicle concerned, an intermediate torque transmission stage, preferably with modification of the rotational speed, comprising an intermediate shaft and a rotational movement output stage, with a member kinematically connected to at least one pair of wheels to be driven, such as a shaft, a pinion or a toothed wheel, and

[0010] the input shaft, the output member and the intermediate shaft having respective axes of rotation parallel to each other, at least one meshing connection existing between the input shaft and the intermediate shaft, on the one hand, and between the intermediate shaft and the output member, on the other hand.

[0011] According to a first aspect of the invention, the aforementioned transmission device is characterized in that the input shaft comprises two first toothed wheels mounted free to rotate on this shaft and the intermediate shaft comprises two second toothed wheels mounted fixed on this shaft, each first toothed wheel meshing respectively with a second toothed wheel and each pair of mutually meshing wheels having its own transmission ratio,

[0012] in that the input stage is configured to provide selective torque transmission and for this purpose comprises at least one coupling member which can be switched in a controlled manner between two positions or two states, for example by translational movement along the axis of rotation of this stage, the or each coupling member being configured to secure in rotation one of the two first toothed wheels with the input shaft, this selectively depending on the position or state of said or each coupling member, and

[0013] in that the input stage comprises a clutch associated with one of the first two toothed wheels, preferably the one establishing a torque transmission with the highest resulting rotational speed for the intermediate shaft, this clutch being configured to selectively establish a rotational securing connection between this first toothed wheel and the input shaft, this connection being complementary to that capable of being established by the at least one coupling member.

[0014] According to a second aspect of the invention, the aforementioned transmission device is characterized in that the input shaft comprises two first toothed wheels mounted fixedly on this shaft and the intermediate shaft comprises two second toothed wheels mounted freely in rotation on this shaft, each first toothed wheel meshing respectively with a second toothed wheel and each pair of wheels mutually en- gears with a clean transmission ratio,

[0015] in that the intermediate stage is configured to provide selective torque transmission and for this purpose comprises at least one coupling member which can be switched in a controlled manner between two positions or two states, for example by translational movement along the axis of rotation of this stage, the or each coupling member being configured to secure in rotation one of the two second toothed wheels with the intermediate shaft, this selectively depending on the position or state of said or each coupling member and

[0016] in that the intermediate stage comprises a clutch associated with one of the two second toothed wheels, preferably the one establishing a torque transmission with the highest resulting rotational speed for the intermediate shaft, this clutch being configured to selectively establish a rotational securing connection between this second toothed wheel and the intermediate shaft, this connection being complementary to that capable of being established by the at least one coupling member.

[0017] It is noted that in its two aforementioned aspects, the invention proposes entirely similar solutions based on the same basic inventive concept, with the only difference being that the roles of the input stage and the intermediate stage are simply reversed. Indeed, the selective transmission of torque and the presence of a clutch are associated with the input stage in the first aspect of the invention and are associated with the intermediate stage in the second aspect.

[0018] The invention also relates to an axle for the propulsion or traction of an electric vehicle, this axle integrating a transmission device according to one of the two aspects of the invention mentioned above.

[0019] The invention will be better understood from the following description, which relates to preferred embodiments in relation to the two aspects of the invention, given as non-limiting examples, and explained with reference to the appended schematic drawings, in which:

[0020] [Fig. 1 A] is a schematic and symbolic representation of a first mode of production of a transmission device in relation to the first aspect of the invention;

[0021] [Fig.lB] is a schematic and symbolic representation of a second embodiment of a transmission device in relation to the second aspect of the invention;

[0022] [Fig.2A] is a constructive variant of the transmission device of [Fig.1A], and,

[0023] [Fig.2B] is a constructive variant of the transmission device of [Fig.1B].

[0024] Figures 1 and 2 illustrate schematically and in accordance with the two aspects of the invention, a transmission device (1) for an electric vehicle, providing a torque transmission path by meshing, between the engine (2) of said vehicle and at least one of its wheels (4), preferably two mounted on an axle provided with a differential (3').

[0025] This device (1) essentially comprises a stage (5) for input of rotational movement, with an input shaft (5') kinematically connected to the electric motor (2) of the vehicle concerned, an intermediate stage (6) for transmission of torque, preferably with modification of the rotational speed, comprising an intermediate shaft (6') and a stage (7) for output of rotational movement, with a member (7') kinematically connected to at least one pair of wheels (4) to be driven, such as a shaft, a pinion or a toothed wheel,

[0026] The input shaft (5), the output member (7) and the intermediate shaft (6') have respective axes of rotation (AE, AS, AI) parallel to each other, and at least one meshing connection exists between the input shaft (5) and the intermediate shaft (6'), on the one hand, and between the intermediate shaft (6') and the output member (7), on the other hand, with permanent or selective transmission of movement / torque depending on the case as indicated below.

[0027] In accordance with a first aspect or embodiment of the transmission device (1) according to the invention, having the aforementioned common arrangements and shown in the form of two variants in FIGS. 1A and 2A, the input shaft (5) comprises two first toothed wheels (8 and 8') mounted freely in rotation on this shaft (5) and the intermediate shaft (6') comprises two second toothed wheels (9 and 9') mounted fixedly on this shaft (6'), each first toothed wheel (8, 8') meshing respectively with a second toothed wheel (9, 9') and each pair of mutually meshing wheels having its own transmission ratio (RI, R2).

[0028] Furthermore, this input stage (5) is configured to ensure selective torque transmission and for this purpose comprises at least one coupling member (10, 10') which can be switched in a controlled manner between two positions or two states, for example by translational movement along the axis of rotation (AE) of this stage, the or each coupling member (10, 10') being configured to secure in rotation one of the two first toothed wheels (8, 8') with the input shaft (5'), this selectively depending on the position or state of said or each coupling member (10, 10').

[0029] Furthermore, the input stage (5) comprises a clutch (11) associated with one (8') of the two first toothed wheels (8, 8'), preferably the one establishing a torque transmission with the highest resulting rotational speed for the intermediate shaft (6'), this clutch (11) being configured to selectively establish a rotational securing connection between this first toothed wheel (8') and the input shaft (5'), this connection being complementary to that likely to be established by the coupling member (10) at least present.

[0030] Thanks to these particular additional arrangements essentially related to the input stage (5), the invention makes it possible to achieve the main aim mentioned above.

[0031] According to a first practical constructive variant compatible with this first embodiment (figure 1 A), the transmission device (1) comprises a single selective coupling member (10) which consists of a dog clutch mounted sliding on the input shaft (5') and which is arranged and configured to establish, in a first engaged position, a rotational connection between this shaft (5') and one (8) of the two first toothed wheels (8, 8') and, in a second engaged position, a rotational connection between this shaft (5') and another (8') of said first toothed wheels (8, 8'), these two engaged positions being separated by a neutral position of said member (10) corresponding to a simultaneous absence of connection of the two first toothed wheels (8 and 8') with said shaft (5'). The possibility of a neutral position allows a kinematic disconnection between the motor and the wheels.Still according to this variant, the transmission device (1) also comprises a clutch (11) configured and controlled to selectively establish a rotational securing connection between the first toothed wheel (8') concerned and the input shaft (5'), which is variable and controlled in intensity as a function of the position of the coupling member (10), this clutch (11) advantageously consisting of a friction or sliding clutch. This progressive engagement clutch makes it possible to guarantee the maintenance of the torque during gear changes and to ensure the continuity of transmission of said torque.

[0032] According to a second practical constructive variant compatible with this first embodiment ([Fig.2A]), the transmission device (1) comprises a first selective coupling member (10) which consists of a dog clutch mounted to slide on the input shaft (5') and which is arranged and configured to establish, in a first engaged position, a rotational connection between this shaft (5') and one (8) of the first toothed wheels (8, 8') and, in a second disengaged position, a rotational disconnection between this shaft (5') and this toothed wheel (8).In addition, said transmission device (1) also comprises a second coupling member (10') corresponding to the clutch (11) associated with the other (8') of the first toothed wheels (8, 8') and configured and controlled to selectively establish a rotational securing connection between this other first toothed wheel (8') concerned and the input shaft (5'), this alternately and in an inverse manner with respect to the connection established by the first coupling member (10), this clutch (11) advantageously consisting of a multiple-disc clutch, mounted integral in rotation with one of the input shaft (5') and this other first toothed wheel (8') and being able to be selectively . secured in rotation with the other of the input shaft (5') and this first toothed wheel (8') by a third coupling member (12). In this variant also, the continuity of transmission of the torque is ensured, as well as its progressive transfer, during gear changes. In addition, a simple dog clutch is sufficient and a possible kinematic disconnection can also be achieved.

[0033] In accordance with a second aspect or embodiment of the transmission device (1) according to the invention, having the aforementioned common arrangements and shown in the form of two variants in Figures 1B and 2B, the input shaft (5) comprises two first toothed wheels (8 and 8') fixedly mounted on this shaft (5) and the intermediate shaft (6') comprises two second toothed wheels (9 and 9') mounted free to rotate on this shaft (6'), each first toothed wheel (8, 8') meshing respectively with a second toothed wheel (9, 9') and each pair of mutually meshing wheels having its own transmission ratio (RI, R2),

[0034] In addition, the intermediate stage (6) is configured to ensure selective torque transmission and for this purpose comprises at least one coupling member (10, 10') which can be switched in a controlled manner between two positions or two states, for example by translational movement along the axis of rotation (AI) of this stage, the or each coupling member (10, 10') being configured to secure in rotation one of the two second toothed wheels (9, 9') with the intermediate shaft (6'), this selectively depending on the position or state of said or each coupling member (10, 10').

[0035] Furthermore, this intermediate stage (6) comprises a clutch (11) associated with one (9') of the two second toothed wheels (9, 9'), preferably the one establishing a torque transmission with the highest resulting rotational speed for the intermediate shaft (6'), this clutch (11) being configured to selectively establish a rotational securing connection between this second toothed wheel (9') and the intermediate shaft (6'), this connection being complementary to that capable of being established by the coupling member (10) at least present.

[0036] Thanks to these particular additional arrangements essentially related to the intermediate stage (6), the invention makes it possible to achieve the main aim mentioned above.

[0037] According to a first practical constructive variant compatible with this second embodiment ([Fig.lB]), the transmission device (1) comprises a single selective coupling member (10) which consists of a dog clutch mounted to slide on the intermediate shaft (6') and which is arranged and configured to establish, in a first engaged position, a rotational connection between this shaft (6') and one (9) of the first toothed wheels (9, 9') and, in a second engaged position, a rotational connection between this shaft (6') and another (9') of said first toothed wheels (9, 9'), these two engaged positions being separated by a neutral position of said member (10) corresponding to a simultaneous absence of securing of the two second toothed wheels (9 and 9') with said shaft (6'). Still according to this variant, the transmission device (1) also comprises a clutch (11) configured and controlled to selectively establish a rotational securing connection between the second toothed wheel (9') concerned and the intermediate shaft (6'), which is variable and controlled in intensity as a function of the position of the coupling member (10), this clutch (11) advantageously consisting of a friction or sliding clutch.

[0038] According to a second practical constructive variant compatible with this second embodiment ([Fig.2B]), the transmission device (1) comprises a first selective coupling member (10) which consists of a dog clutch mounted to slide on the intermediate shaft (6') and which is arranged and configured to establish, in a first engaged position, a rotational connection between this shaft (6') and one (9) of the two second toothed wheels (9, 9') and, in a second disengaged position, a rotational disconnection between this shaft (6') and this toothed wheel (9).Still within the framework of this second variant, the transmission device (1) also comprises a second coupling member (10') corresponding to the clutch (11) associated with the other (9') of said second toothed wheels (9, 9') and configured and controlled to selectively establish a rotational securing connection between this other second toothed wheel (9') concerned and the intermediate shaft (6'), this alternately and in an inverse manner with respect to the connection established by the first coupling member (10), this clutch (11) advantageously consisting of a multiple-disc clutch, mounted integral in rotation with one of the intermediate shaft (6') and this other second toothed wheel (9') and being able to be selectively secured in rotation with the other of the intermediate shaft (6') and this second toothed wheel (9') by a third coupling member (12).

[0039] The two variants of this second embodiment, which have similar constructive characteristics to the two variants of the first embodiment, also respectively have the same advantages already mentioned previously.

[0040] In the various variants and embodiments mentioned above, the transmission ratios are determined, by determining the respective diameters of the two wheels of each pair of first and second meshing toothed wheels (8 and 9; 8' and 9'), in such a way that the first ratio makes it possible to achieve the desired maximum torque objective and that the second ratio makes it possible to achieve the desired maximum speed objective (this of course in relation to the constructively fixed transmission ratio between the intermediate stage and the output stage).

[0041] In order to allow safe immobilization of the vehicle when stationary (position parking), the transmission device (1) may comprise a device for locking the rotation of the intermediate shaft (6'), either directly or by locking one of the first toothed wheels (8, 8'). For this purpose, the intermediate shaft (6') may be provided with a toothed or ratchet wheel (13) fixedly mounted on this shaft or integral with one of the aforementioned toothed wheels (8, 8') and the rotation of which may be selectively locked by a suitable mechanism controlled directly or indirectly by user command (see for example FR 3 121 409).

[0042] Preferably, and in relation to the type of vehicle concerned, the transmission device (1) comprises electromagnetic actuators for controlling the switching of the coupling member(s) (10, 10') and / or the engagement and disengagement of the clutch (11).

[0043] The invention also relates, as shown in [Fig.lA] and partially in the other figures, to an axle for the propulsion or traction of an electric vehicle, comprising the motor (2) of said vehicle and a shaft (3) carrying a pair of drive wheels (4) of said vehicle, this shaft (3) possibly comprising a differential (3').

[0044] This axle also comprises a device (1) for transmitting movement between the motor (2) and the aforementioned wheels (4), and this axle is characterized in that said transmission device (1) consists of a device as described previously in relation to the two aspects of the invention, the movement (or torque) input and output members (5 and 7) and the intermediate stage (6) being mounted together in a common casing (not shown), the latter advantageously also housing the motor (2) and possibly the differential (3'). As shown in the figures, the output member (7) of the movement transmission device (1) can advantageously correspond to the input wheel of the differential (3').

[0045] Finally, the invention also relates to an electric motor vehicle, characterized in that it comprises a device (1) for transmitting movement, between its motor (2) and its propulsion or traction wheels (4), this device being advantageously integrated, with this motor (2) and with the shaft (3) carrying these wheels (4), in an axle.

[0046] In relation to the two variants of the first embodiment of the invention, illustrated in Figures 1A and 2A, the two speed ratios are advantageously established as follows:

[0047] - 1st gear ratio (low speed and high torque; transmission ratio RI) is carried out with the dog clutch (10) engaged with the first gear wheel (8) and the clutch (11) open

[0048] -the 2nd gear ratio (high speed and low torque, transmission ratio R2, with R2>R1 and for example R1<1 <R2) est réalisé soit avec le crabot (10) engagé avec la première roue dentée (8’) et l’embrayage (11) ouvert - [Fig. IA]-, soit avec le crabot (10) disengaged and the clutch (10', 11) engaged -[Fig.2A].

[0049] In relation to the embodiment of [Fig.lA], the change from first gear to second gear (without interruption of transmitted torque) advantageously takes place as follows:

[0050] -in the first gear, the torque is transmitted from the engine (2) to the intermediate shaft (6') exclusively by means of the dog clutch (10) engaged with the first toothed wheel (8), the clutch (11) being completely disengaged,

[0051] - the engagement of the clutch (11) is controlled, and the latter increases in capacity with a progressive transfer of the torque passing through the dog clutch (10) to the clutch (11),

[0052] - the dog clutch (10) is disengaged from the first toothed wheel (8) and is in the neutral position (as shown in [Fig.lA]), the entire torque then passes through the clutch (11),

[0053] - the braking of the clutch slip (11) occurs and, during this phase inertia, the sliding speed is gradually brought back to 0,

[0054] - the engagement of the dog clutch (10) with the other first toothed wheel (8') begins (the torque still being mainly transmitted by the clutch),

[0055] - the clutch (11) is controlled to decrease in capacity with a transfer progressive torque passing through the clutch (11) to the dog clutch (10),

[0056] -after finalizing the engagement of the dog clutch (10) with this other first toothed wheel (8'), the torque is exclusively transmitted by the dog clutch (10), the clutch (11) being completely disengaged.

[0057] Thanks to the invention, taken in each of its embodiments described above and illustrated in the figures appended as examples, it is therefore possible to provide a transmission device (1) with a simple and economical structure (in particular not containing a planetary gear set), making it possible to achieve a priori contradictory performance objectives (possibility of having a maximized output torque and a maximized vehicle speed with the same device) and having optimal efficiency in the two possible ratios (no residual dissipated power when a ratio is engaged). In addition, this device does not show any interruption in the transmission of torque from the engine to the wheels during upshifts and downshifts, and advantageously includes a neutral position (complete disengagement) ensuring a disconnection between the engine and the wheels (load limitation when the parking device is engaged).

[0058] Of course, the invention is not limited to the embodiments described and shown in the attached drawings. Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims

Claims

1. Axle for the propulsion or traction of an electric vehicle, comprising the motor (2) of said vehicle and a shaft (3) carrying a pair of drive wheels (4) of said vehicle, this shaft (3) possibly comprising a differential (3'), this axle also comprising a device (1) for transmitting movement between the motor (2) and the aforementioned wheels (4), this device (1) essentially comprising a stage (5) for input of rotational movement, with an input shaft (5') kinematically connected to the electric motor (2) of the vehicle concerned, an intermediate stage (6) for transmitting torque, preferably with modification of the rotational speed, comprising an intermediate shaft (6') and a stage (7) for output of rotational movement, with a member (7') kinematically connected to at least one pair of wheels (4) to be driven, such as a shaft, a pinion or a toothed wheel, the input shaft (5),the output member (7) and the intermediate shaft (6') having respective axes of rotation (AE, AS, AI) parallel to each other, at least one meshing connection existing between the input shaft (5) and the intermediate shaft (6'), on the one hand, and between the intermediate shaft (6') and the output member (7), on the other hand, the input shaft (5) comprising two first toothed wheels (8 and 8') mounted freely in rotation on this shaft (5) and the intermediate shaft (6') comprising two second toothed wheels (9 and 9') mounted fixedly on this shaft (6'), each first toothed wheel (8, 8') meshing respectively with a second toothed wheel (9, 9') and each pair of mutually meshing wheels having its own transmission ratio (RI, R2), the input stage (5) being configured to ensure selective torque transmission and comprising for this purpose at least one coupling member (10, 10') which can be controlled to switch between two positions or two states,for example by translational movement along the axis of rotation (AE) of this stage, the or each coupling member (10, 10') being configured to secure in rotation one of the two first toothed wheels (8, 8') with the input shaft (5'), this selectively depending on the position or state of said or each coupling member (10, 10'), and,

2.

3. in that the input stage (5) comprises a clutch (11) associated with one (8') of the two first toothed wheels (8, 8'), preferably the one establishing a torque transmission with the highest resulting rotational speed for the intermediate shaft (6'), this clutch (11) being configured to selectively establish a rotational securing connection between this first toothed wheel (8') and the input shaft (5'), this connection being complementary to that capable of being established by the coupling member (10) at least present, axle characterized in that the motion or torque input and output stages (5 and 7) and the intermediate stage (6) are mounted together in a common casing, the latter also housing the motor (2) and possibly the differential (3'), and, in that the transmission device (1) further comprises, on the one hand, a device for locking the intermediate shaft (6') in rotation, either directly or by locking one of the first toothed wheels (8, 8'), and, on the other hand, electromagnetic actuators for controlling the switching of the coupling member(s) (10, 10') and / or the engagement and disengagement of the clutch (11). Axle according to claim 1, characterized in that it comprises a single selective coupling member (10) which consists of a dog clutch mounted to slide on the input shaft (5') and which is arranged and configured to establish, in a first engaged position, a rotational connection between this shaft (5') and one (8) of the first toothed wheels (8, 8') and, in a second engaged position, a rotational connection between this shaft (5') and another (8') of said first toothed wheels (8, 8'),these two engaged positions being separated by a neutral position of said member (10) corresponding to a simultaneous absence of securing of the two first toothed wheels (8 and 8') with said shaft (5'), and in that it comprises a clutch (11) configured and controlled to selectively establish a rotational securing connection between the first toothed wheel (8') concerned and the input shaft (5'), which is variable and controlled in intensity as a function of the position of the coupling member (10), this clutch (11) advantageously consisting of a friction or sliding clutch., Axle according to claim 1, characterized in that it comprises a first selective coupling member (10) which consists of a dog clutch

4. slidably mounted on the input shaft (5') and which is arranged and configured to establish, in a first engaged position, a rotational connection between this shaft (5') and one (8) of the first toothed wheels (8, 8') and, in a second disengaged position, a rotational disconnection between this shaft (5') and this toothed wheel (8), and in that it comprises a second coupling member (10') corresponding to the clutch (11) associated with the other (8') of the first toothed wheels (8, 8') and configured and controlled to selectively establish a rotational securing connection between this other first toothed wheel (8') concerned and the input shaft (5'), this alternately and in an inverse manner with respect to the connection established by the first coupling member (10), this clutch (11) advantageously consisting of a multiple-disc clutch,mounted integral in rotation with one of the input shaft (5') and this other first toothed wheel (8') and being able to be selectively secured in rotation with the other of the input shaft (5') and this first toothed wheel (8') by a third coupling member (12). Axle for the propulsion or traction of an electric vehicle, comprising the motor (2) of said vehicle and a shaft (3) carrying a pair of drive wheels (4) of said vehicle, this shaft (3) possibly comprising a differential (3'), this axle also comprising a device (1) for transmitting movement between the motor (2) and the aforementioned wheels (4), this device (1) essentially comprising a stage (5) for input of rotational movement, with an input shaft (5') kinetically connected to the electric motor (2) of the vehicle concerned, an intermediate stage (6) for transmitting torque, preferably with modification of the rotational speed,comprising an intermediate shaft (6') and a stage (7) for outputting rotational movement, with a member (7') kinematically connected to at least one pair of wheels (4) to be driven, such as a shaft, a pinion or a toothed wheel, the input shaft (5), the output member (7) and the intermediate shaft (6') having respective axes of rotation (AE, AS, AI) parallel to each other, at least one meshing connection existing between the input shaft (5) and the intermediate shaft (6'), on the one hand, and between the intermediate shaft (6') and the output member (7), on the other hand, the input shaft (5) comprising two first toothed wheels (8 and 8') fixedly mounted on this shaft (5) and the intermediate shaft (6') comprising, two second toothed wheels (9 and 9') mounted freely in rotation on this shaft (6'), each first toothed wheel (8, 8') meshing respectively with a second toothed wheel (9, 9') and each pair of mutually meshing wheels having its own transmission ratio (RI, R2), the intermediate stage (6) being configured to ensure selective torque transmission and comprising for this purpose at least one coupling member (10, 10') which can be switched in a controlled manner between two positions or two states, for example by translational movement along the axis of rotation (AI) of this stage, the or each coupling member (10, 10') being configured to secure in rotation one of the two second toothed wheels (9, 9') with the intermediate shaft (6'), this selectively depending on the position or state of said or each coupling member (10,10') and the intermediate stage (6) comprising a clutch (11) associated with one (9') of the two second toothed wheels (9, 9'), preferably the one establishing a torque transmission with the highest resulting rotational speed for the intermediate shaft (6'), this clutch (11) being configured to selectively establish a rotational securing connection between this second toothed wheel (9') and the intermediate shaft (6'), this connection being complementary to that capable of being established by the coupling member (10) at least present, axle characterized in that the stages (5 and 7) for input and output of movement or torque and the intermediate stage (6) are mounted together in a common casing, the latter also housing the motor (2) and possibly the differential (3'), and, in that the transmission device (1) further comprises, on the one hand, a device for locking the rotation of the intermediate shaft (6'), either directly,either by blocking one of the first toothed wheels (8, 8'), and, on the other hand, electromagnetic actuators for controlling the switching of the coupling member(s) (10, 10') and / or the engagement and disengagement of the clutch (11).,

5. Axle according to claim 4, characterized in that it comprises a single selective coupling member (10) which consists of a dog clutch mounted to slide on the intermediate shaft (6') and which is arranged and configured to establish, in a first engaged position, a solida-

6.

7. rotational engagement between this shaft (6') and one (9) of the first toothed wheels (9, 9') and, in a second engaged position, a rotational securing between this shaft (6') and another (9') of said first toothed wheels (9, 9'), these two engaged positions being separated by a neutral position of said member (10) corresponding to a simultaneous absence of securing of the two second toothed wheels (9 and 9') with said shaft (6'), and in that it comprises a clutch (11) configured and controlled to selectively establish a rotational securing connection between the second toothed wheel (9') concerned and the intermediate shaft (6'), which is variable and controlled in intensity as a function of the position of the coupling member (10), this clutch (11) advantageously consisting of a friction or sliding clutch. Axle according to claim 4, characterized in that it comprises a first selective coupling member (10) which consists of a dog clutch mounted slidingly on the intermediate shaft (6') and which is arranged and configured to establish, in a first engaged position, a rotational connection between this shaft (6') and one (9) of the two second toothed wheels (9, 9') and, in a second disengaged position, a rotational disconnection between this shaft (6') and this toothed wheel (9), and in that it comprises a second coupling member (10') corresponding to the clutch (11) associated with the other (9') of said second toothed wheels (9, 9') and configured and controlled to selectively establish a rotational securing connection between this other second toothed wheel (9') concerned and the intermediate shaft (6'), this alternately and in an inverse manner with respect to the connection established by the first coupling member (10),this clutch (11) advantageously consisting of a multiple-disc clutch, mounted integral in rotation with one of the intermediate shaft (6') and this other second toothed wheel (9') and capable of being selectively secured in rotation with the other of the intermediate shaft (6') and this second toothed wheel (9') by a third coupling member (12)., Electric motor vehicle, characterized in that it comprises an axle with a motion transmission device (1), according to any one of claims 1 to 6.

Images