MOTOR MODULE AND HYBRID TRANSMISSION ASSEMBLY OF A VEHICLE

Abstract

The invention relates to a motorized module (60) for driving and slowing down an intermediate shaft of a hybrid transmission assembly, said motorized module comprising: - at least one reversible electric machine (61) attached to a protective casing (62), - a connection device (70) arranged to connect the at least one reversible electric machine (61) to the intermediate shaft (26), and - a speed reducer (100) arranged kinematically between the at least one reversible electric machine and the connection device (70), the connection device (70) comprising: - a connection shaft (71) rotatable relative to the protective casing along a main axis (X),- a dog clutch (80) supported by the connecting shaft (71) and arranged to rotationally lock the connecting shaft with the protective casing in a first operating state or rotationally couple the connecting shaft with an output pinion (108) of the speed reducer (100) in a second operating state. (Fig. 1),

Description

Title of the invention: MOTORIZED MODULE AND hybrid TRANSMISSION assembly of a vehicle Technical field of the invention

[0001] The invention relates to a hybrid transmission assembly intended to be positioned between an engine, for example a thermal engine, and a set of one or more drive wheels of a vehicle. It relates in particular, although not exclusively, to such an assembly intended to equip a heavy goods vehicle, that is to say a road vehicle of more than 3.5 tonnes, in particular a road tractor, or a carrier. The invention also relates to a motorized module capable of being integrated within the hybrid transmission assembly. state of the prior art

[0002] Vehicle transmission assemblies of the gearbox type are known, comprising a primary shaft intended to be driven by a thermal engine of the vehicle, a secondary shaft intended to drive drive wheels of the vehicle and an intermediate shaft capable of being coupled to the output shaft and to the input shaft by gear trains corresponding to different speed ratios.

[0003] Document EPI592590 A1 teaches using a gearbox brake coupled to the intermediate shaft of the gearbox to brake the intermediate shaft during transient gear ratio change phases, which makes it possible to promote synchronization of the gearbox and thus reduce the duration of the transient gear ratio change phases.

[0004] Document DE102005043703 A1 discloses a reversible electric machine that is permanently coupled to the intermediate shaft of a transmission assembly. The reversible electric machine is thus capable of operating in current generator mode to decrease the speed of the intermediate shaft or in motor mode to increase the speed of the intermediate shaft during transient gear change phases in order to promote synchronization of the gearbox. In this document, the reversible electric machine is always linked to the intermediate shaft and thus generates a drag torque increasing the fuel consumption of the main engine.Furthermore, in the event of a malfunction of the reversible electric machine or when the battery has reached its maximum charge such that using the reversible electric machine to brake the intermediate shaft would risk damaging it, it is then no longer possible to brake the intermediate shaft of the gearbox during the transient phases of gear changes, which poses safety problems in particular. Statement of the invention

[0005] An idea underlying the invention is to propose a motorized module for driving and slowing down an intermediate shaft of a hybrid transmission assembly which makes it possible to overcome the drawbacks of the state of the art by allowing the use of a reversible electric machine to synchronize the gear changes of the gearbox without increasing the consumption of the main engine or impairing the safety of the vehicle.

[0006] To do this, according to a first aspect of the invention, a motorized module is proposed for driving and slowing down an intermediate shaft of a hybrid transmission assembly, said motorized module comprising:

[0007] - at least one reversible electrical machine attached to a protective casing,

[0008] - a connection device arranged to connect the at least one machine reversible electric to the intermediate shaft, and

[0009] - a speed reducer arranged kinematically between the at least one machine reversible electric and connection device,

[0010] the connection device comprising:

[0011] - a connection shaft movable in rotation relative to the protective casing according to a main axis X,

[0012] - a dog clutch supported by the connecting shaft and arranged to lock in rotating the connecting shaft with the protective housing in a first operating state or rotatingly coupling the connecting shaft with an output pinion of the speed reducer in a second operating state, and

[0013] - a multi-disc type wet clutch kinematically linked to the shaft of connection including:

[0014] - a torque input disc carrier partially supporting a mul assembly discs and arranged to be rotatably connected to the intermediate shaft, and

[0015] - an actuation system for configuring the wet clutch either in a engaged position, either in a disengaged position or in a torque sliding position,

[0016] and wherein the wet clutch configured in its engaged position couples the connecting shaft to the intermediate shaft when the dog clutch is in the second operating state, or the wet clutch configured in its torque slip position slows the intermediate shaft relative to the protective housing when the dog clutch is in the first operating state.

[0017] The interposition of such a connection device between the reversible electric machine and the intermediate shaft makes it possible to envisage operating modes such as those described in the state of the art when the wet clutch is engaged, and additional operating modes in which the reversible electric machine can be decoupled, either because it is not required for the operation of the hybrid transmission assembly or because it is used for other purposes, for example for driving another rotating member. Furthermore, decoupling the electric machine relieves the load on the rotor guide bearings of the electric machine, thereby increasing their service life.

[0018] Thus, thanks to the wet clutch, the reversible electric machine can be uncoupled from the intermediate shaft outside of the transient phases of gear change, which makes it possible to reduce the consumption of the main engine.

[0019] Also, by placing the dog clutch in a first operating state, the wet clutch is capable of acting as a gearbox brake without stressing the reversible electric machine, in particular in the event of failure of the reversible electric machine or when the battery powering the reversible electric machine has reached its maximum charge. The wet clutch is also capable of acting as a gearbox brake when the battery fails.

[0020] Advantageously, the wet clutch and the dog clutch may be axially aligned and concentric to reduce axial compactness.

[0021] Preferably, the wet clutch and the dog clutch can be operated independently. It is thus possible to reduce the operating times of the motorized module depending on the operating state of the vehicle.

[0022] The reversible electrical machine may in particular be a permanent magnet synchronous machine, an asynchronous machine, a variable reluctance electrical machine or a variable reluctance synchronous electrical machine, known as synchro-reluctant.

[0023] The reversible electrical machine may in particular be supplied with a nominal voltage of 48 volts, said electrical machine comprising a stator and a rotor having an output shaft which can rotate around a rotor axis R.

[0024] According to a characteristic of the invention, the dog clutch may comprise a sliding dog clutch sleeve mounted to slide axially on the connection shaft and which comprises internal axial splines adapted to mesh with external axial splines of the connection shaft.

[0025] Preferably, in a neutral phase of operation of the dog clutch, the sliding sleeve completely covers the external axial splines of the connecting shaft without meshing with the output pinion of the speed reducer and the protective casing. In this neutral phase of operation, there is complete disconnection of the motorized module with the gearbox of the hybrid transmission assembly.

[0026] Advantageously, the dog clutch sliding sleeve may have a substantially cylindrical shape around the main axis X, a first axial end of the sliding sleeve is shaped into a first series of sliding splines capable of meshing with the protective casing and a second axial end of the sliding sleeve is shaped into a second series of sliding splines capable of meshing with the output pinion of the speed reducer.

[0027] Preferably, the output pinion of the speed reducer may comprise a series of axial dog teeth oriented radially outwards and arranged to cooperate with the second series of sliding gear splines.

[0028] Advantageously, the protective casing may comprise a series of teeth carried by a crown and arranged to cooperate with the first series of sliding gear splines.

[0029] Preferably, the crown can be carried or attached to an inner face of the protective casing.

[0030] According to an alternative embodiment of the invention, the first series of sliding sleeve grooves and the second series of sliding sleeve grooves may be contiguous and axially aligned to form a single set of internal axial grooves of the sliding sleeve.

[0031] According to another variant embodiment of the invention, the first series of sliding gear splines and the second series of sliding gear splines are radially offset.

[0032] Preferably, the multi-disc type wet clutch may comprise a torque output disc carrier rotatably connected to the connecting shaft by spline, by shrink fit or by screwed assembly.

[0033] Alternatively, the torque output disc carrier and the connecting shaft may form a single part.

[0034] Advantageously, the multi-disc type wet clutch may comprise a multi-disc assembly consisting of a first set of discs engaged with splines of the torque input disc carrier, and a second set of discs engaged with splines of the torque output disc carrier.

[0035] According to one embodiment, the multi-disc assembly of the wet clutch can be pressed axially by an annular-shaped actuating piston, coaxial with the connecting shaft, the actuating piston being guided axially within a pressure chamber formed directly or indirectly in the protective casing.

[0036] Advantageously, the actuating piston may comprise on its free end located outside the pressure chamber a support bearing which presses on the multi-disc assembly, for example a radial bearing or a ball bearing, making it possible to decouple in rotation the multi-disc assembly from the protective casing when the dog clutch is in the second operating state.

[0037] According to another embodiment, the multi-disc assembly of the wet clutch can be pressed axially by an annular-shaped actuating piston, coaxial with the connecting shaft, the actuating piston being guided axially within a pressure chamber formed directly or indirectly in the connecting shaft.

[0038] Advantageously, the actuating piston can press directly on the multi-disc assembly, in particular on the end disc of the second set of discs engaged with the grooves of the torque output disc holder.

[0039] In all of the above, the pressure chamber of the actuating piston may be supplied with a fluid, for example air or oil.

[0040] Preferably, the output pinion of the speed reducer can guide the connection shaft in rotation by means of a guide bearing arranged axially at least partially within the dog clutch.

[0041] According to a characteristic of the invention, a portion of the protective cover can be interposed axially between the wet clutch and the dog clutch, the portion being for example a wall made from the same material as the protective cover or a support plate attached to the protective cover.

[0042] Preferably, the connection device can be arranged kinematically between the speed reducer and the intermediate shaft, which avoids driving the speed reducer continuously.

[0043] According to a particularly advantageous embodiment, the motorized module comprises a power take-off member, kinematically linked to the reversible electric machine, preferably via the speed reducer. The module thus integrates a power take-off function. It is then possible to envisage driving the power take-off by the reversible electric machine without using the main engine of the vehicle, which makes it possible to achieve rotation speeds very significantly higher than 1000 rpm, for example higher than 1500 rpm, and where appropriate up to 5000 rpm.

[0044] The speed reducer may advantageously comprise a gear train or a belt reducer. In this way, the speed reducer makes it possible to adapt the rotational speed of the electric machine to the needs of the hybrid transmission assembly.

[0045] Advantageously, the torque input disc holder may comprise a connecting interface arranged to be rotationally connected to the intermediate shaft. The connecting interface may be, for example, a splined shaft section, a splined sleeve or a shaft provided with a key.

[0046] Preferably, the motorized module comprises a protective casing having the function of protecting the reversible electric machine, the speed reducer and the connection device, the reversible electric machine being either housed in the protective casing or fixed to the protective casing. The connection interface with the intermediate shaft can either be housed in the casing or protrude outside the casing.

[0047] According to a characteristic of the invention, the speed reducer can comprise:

[0048] - a drive shaft supporting drive toothed wheels capable of being driven by the output shaft of the reversible electric machine;

[0049] - a complementary shaft capable of being driven by complementary toothed wheels mentaries, each drive gear wheel being kinematically linked to a corresponding complementary gear wheel so as to form a pair of gears; and

[0050] - the output pinion of the speed reducer kinematically linked with the com shaft additional;

[0051] wherein a coupling device, disposed between the drive gears and the complementary gears, selects a first pair of gears to obtain a first reduction ratio or a second pair of gears to obtain a second reduction ratio from a neutral position.

[0052] According to one embodiment, the motorized module may comprise at least one additional reversible electrical machine for driving the intermediate shaft kinematically linked to the speed reducer. In this case, the drive shaft comprises a common drive toothed wheel meshing with the output pinions of the rotor of the reversible electrical machines.

[0053] According to another aspect of the invention, the latter relates to a hybrid transmission assembly for driving a vehicle, comprising: • a dry-operating clutch mechanism intended to be driven by a main engine of the vehicle; • a friction clutch disc with primary rotation axis XI capable of being driven by the main engine depending on the engaged or disengaged operating position of the clutch mechanism; • a gearbox comprising: • one or more primary toothed wheels driven in rotation by the friction clutch disc along the primary axis of rotation XI, • a secondary shaft intended to drive a set of one or more drive wheels of the vehicle, • several secondary gear wheels capable of being coupled to the secondary shaft, • an intermediate shaft to which intermediate gear wheels are rotationally secured, the primary gear wheel(s) and the secondary gear wheels each meshing permanently with a corresponding gear wheel among the intermediate gear wheels, and • the motorized module incorporating all or part of the characteristics mentioned above, in which the torque input disc holder is attached to the intermediate shaft coaxially, and wherein the at least one reversible electric machine rotates the intermediate shaft when the wet clutch is configured in its engaged position and when the dog clutch is in the second operating state.

[0054] Preferably, the speed reducer may comprise a first gear train connecting the reversible electric machine to the output pinion via a first reduction ratio by actuating a coupling device according to a first position and a second gear train connecting the reversible electric machine to the output pinion via a second reduction ratio by actuating the coupling device according to a second position.

[0055] Advantageously, the coupling device may comprise a neutral position in which neither of the first nor second gear trains is rotated.

[0056] Preferably, the second reduction ratio of the second gear train may be between 8 and 12 in order to allow the main motor to be started by the torque supplied by the reversible electric machine when the dry-operating clutch mechanism is in the engaged operating position combined with the wet clutch configured in its engaged position and the dog clutch being in the second operating state. Thanks to this second reduction ratio, the main motor is restarted by means of the high torque available at the end of the speed reducer with a low rotational speed.

[0057] Advantageously, the first reduction ratio of the first gear train may be between 4 and 6 in order to allow synchronization of one of the secondary gears with the secondary shaft when the dry operating clutch mechanism is in the disengaged operating position combined with the wet clutch configured in its engaged position and the dog clutch being in the second operating state.

[0058] Preferably, the gearbox may comprise at least one dog clutch positioned kinematically between one of the secondary toothed wheels and the secondary shaft and capable of coupling the secondary shaft to the associated secondary toothed wheel, said dog clutch being engaged when the rotation speeds of the secondary toothed wheel and the secondary shaft are synchronized by driving or slowing down the intermediate shaft thanks to the activation of the reversible electric machine, and said dog clutch being disengaged when the reversible electric machine starts the main engine.

[0059] According to one embodiment, the hybrid transmission assembly may further comprise a power take-off member, capable of being driven at least by the reversible electric machine. It is then possible to envisage driving the power take-off by the reversible electric machine without using the main engine of the vehicle, which makes it possible to achieve rotation speeds significantly higher than 1000 rpm, by example above 1500 rpm, and where appropriate up to 5000 rpm. Various types of connection can be considered.

[0060] Advantageously, the power take-off member can be securely connected in rotation to the output pinion of the speed reducer, the power take-off member being coaxial with the connection shaft.

[0061] Preferably, the reversible electrical machine may have an axis of revolution parallel to the main axis X of the connection shaft, preferably distant from the main axis X of the connection shaft.

[0062] According to an operating phase, the power take-off member is permanently kinetically connected to the reversible electric machine and is kinetically connected to the intermediate shaft via the connection device. This operating phase will be preferred when it is expected that the main vehicle engine will always be used for driving the power take-off member, the reversible electric machine being used only for additional power. If it is nevertheless desired to uncouple the main engine, the dry-operating clutch mechanism will be disengaged or the coupling mechanism located between the main engine and the primary gears will be opened.

[0063] According to one embodiment, the reversible electric machine has an axis of revolution parallel to an axis of revolution of the intermediate shaft, one or more of the following characteristics being achieved: • the axis of revolution of the reversible electric machine is distant from the axis of revolution of the intermediate shaft; • the axis of revolution of the reversible electric machine is distant from an axis of revolution of the primary toothed wheels; • the axis of revolution of the reversible electric machine is distant from an axis of revolution of the secondary shaft.

[0064] According to one embodiment, the gearbox may comprise a transmission casing delimiting a cavity for housing the primary gear wheels, the secondary gear wheels and the intermediate gear wheels, the protective casing of the motorized module being attached to the transmission casing.

[0065] According to one embodiment, the hybrid transmission assembly comprises a set of one or more primary shafts capable of being driven by the main engine of the vehicle, each of the primary gears being integral with an associated primary shaft of the set of one or more primary shafts or capable of being coupled to an associated primary shaft of the set of one or more primary shafts. Preferably, one or more of the following features are provided: • the primary gears and the secondary gears are coaxial; • one or more dogs provide coupling between the gears secondary to the secondary shaft; • one or more synchronizers provide a coupling between each of the primary gears and an associated primary shaft capable of being driven by the vehicle's main engine. brief description of the figures

[0066] Other characteristics and advantages of the invention will emerge on reading the description which follows, with reference to the appended figures.

[0067] [Fig-1] [Fig.l] illustrates a hybrid transmission assembly comprising a motorized module according to a first embodiment.

[0068] [Fig.2] [Fig.2] illustrates the motorized module according to the first embodiment of [Fig.l].

[0069] [Fig.3] [Fig.3] illustrates a motorized module for a hybrid transmission assembly according to a second embodiment.

[0070] For clarity, identical or similar elements are identified by identical reference signs throughout the figures. DETAILED description of embodiments

[0071] Figures 1 and 2 illustrate a hybrid transmission assembly 1 for driving a vehicle according to a first embodiment of the invention, comprising a primary shaft 12 intended to be driven by a main engine 14 of the vehicle, for example a heat engine, a secondary shaft 16 intended to drive a set of one or more drive wheels of the vehicle, and a gearbox 18.

[0072] The connection of the main engine 14 to the primary shaft 12 comprises a slip clutch mechanism 20 for coupling a friction clutch disc 21 to the main engine 14. The friction clutch disc 21 is rotatably connected to the primary shaft 12 of the gearbox 18. The connection of the secondary shaft 16 to the wheels of the vehicle may include one or more drive axles. The friction clutch disc 21 comprises a torque output hub connected directly to the primary shaft 12 by means of splines.

[0073] The clutch mechanism 20 is controlled by a clutch actuator (not shown) integrated into the gearbox 18. The clutch mechanism 20 is for example of the single-disc type operating in a dry environment.

[0074] The gearbox 18, housed inside a cavity 22 of a transmission casing 24, comprises an intermediate shaft 26 to which intermediate toothed wheels 28, 30, 32, 34, 36 are rotationally secured. Two primary toothed wheels 38, 40 coaxial with the primary shaft 12, each form a gear train with a corresponding toothed wheel 28, respectively 30, among the intermediate toothed wheels. The meshing of the gear trains 38, 28 and 40, 30 between wheels primary gears 38, 40 and the corresponding intermediate gears 28, 30 are permanent. A three-position double synchronizer 41 allows either of the primary gears 38, 40 to be coupled to the primary shaft 12, and provides a neutral position in which neither of the primary gears 38, 40 is coupled to the primary shaft 12.

[0075] Secondary gear wheels 42, 44, 46, coaxial with the secondary shaft 16, also each form a gear train with a corresponding gear wheel 32, 34, 36, respectively, among the intermediate gear wheels, one of the gear trains being reversing and comprising an intermediate wheel 48 for producing a reverse gear. The meshing of the gear trains formed by the secondary gear wheels 42, 44, 46 and the corresponding intermediate gear wheels 32, 34, 36 is permanent. A three-position dog clutch without synchronizers 50, positioned between two of the secondary wheels 44, 46, makes it possible either to couple one or the other of the two associated secondary wheels 44, 46 to the secondary shaft 16, or, in an intermediate neutral position, to keep the associated secondary toothed wheels 44, 46 decoupled from the secondary shaft 16.

[0076] In this embodiment, the axis of revolution XI of the primary shaft 12 is aligned with the axis of revolution of the secondary shaft 16, which makes it possible to use the primary end gear wheel 40 alternately as a primary wheel, associated with the primary shaft 12 by the synchronizer 41, or as a secondary wheel associated with the secondary shaft 16. For this purpose, a three-position dog clutch 52 without synchronizers, positioned between the primary end gear wheel 40 and the secondary wheel 42, makes it possible to couple either the primary end gear wheel 40 or the secondary wheel 42 to the secondary shaft 16, and also makes it possible, in an intermediate neutral position, to keep the primary end gear wheel 40 and the secondary wheel 42 decoupled from the secondary shaft 16.

[0077] This creates a gearbox 18 with six forward gears and potentially two reverse gears, which can, if necessary, be coupled at the output of the secondary shaft 16 to an epicyclic gear train (not shown) in order to obtain a twelve-speed gearbox.

[0078] Remarkably, the hybrid transmission assembly 1 is equipped with a motorized module 60 comprising a reversible electric machine 61 for driving and slowing down the intermediate shaft 26, said electric machine comprising a stator and a rotor having an output shaft that can rotate about a rotor axis R. In this example, the reversible electric machine 61 powered by a battery 43 is attached to a protective casing 62 of the motorized module.

[0079] The motorized module 60 also comprises:

[0080] - a connection device 70 arranged to connect the electrical machine re- reversible 61 to intermediate shaft 26, and

[0081] - a speed reducer 100 arranged kinematically between the electric machine reversible and the connection device,

[0082] the connection device 70 comprising:

[0083] - a connection shaft 71 movable in rotation relative to the protective casing 62 along a main axis X,

[0084] - a dog clutch 80 supported by the connecting shaft and arranged to lock rotating the connecting shaft 71 with the protective casing 62 in a first operating state or rotatingly coupling the connecting shaft 71 with an output pinion 108 of the speed reducer in a second operating state, and

[0085] - a wet clutch 90 of multi-disc type kinematically linked to the shaft of connection including:

[0086] - a torque input disc holder 92 partially supporting a mul assembly 91 discs and arranged to be rotatably connected to the intermediate shaft, and

[0087] - an actuation system 95 for configuring the wet clutch 90 either in an engaged position, either in a disengaged position or in a torque slip position.

[0088] In the connecting device 70, the wet clutch 90 and the dog clutch 80 are axially aligned and concentric. The wet clutch 90 and the dog clutch 80 can be actuated independently. In particular, the wet clutch 90 is pneumatically actuated.

[0089] More precisely, the multi-disc assembly 91 of the wet clutch can be pressed axially by an annular-shaped actuating piston 96, coaxial with the connecting shaft 71. In the present case, the actuating piston 96 is guided axially within a pressure chamber 97 formed directly in the protective casing 62. The actuating piston 96 comprises on its free end located outside the pressure chamber 97 a support bearing 98 pressing on the multi-disc assembly. The support bearing 98 is here a ball bearing making it possible to decouple in rotation the multi-disc assembly 91 from the protective casing 62 when the dog clutch 80 is in the second operating state.

[0090] The wet clutch 90 of the multi-disc type comprises a torque output disc carrier 93 rotatably connected to the connecting shaft 71 by splines and a multi-disc assembly 91 consisting of a first set of discs 91a engaged with splines of the torque input disc carrier 92, and a second set of discs 91b engaged with splines of the torque output disc carrier 93. Thus, when the pressure chamber 97 is supplied with pressurized fluid, the actuating piston 96 moves towards the multi-disc assembly so that the friction discs 91a, 91b are pinched together and the torque is thus transmitted between the connecting shaft 71 and the intermediate shaft 26. The torque input disc carrier 92 is kinematically connected to the intermediate shaft 26 via a connecting interface 64, which may for example be constituted by a splined shaft section or a splined sleeve.

[0091] According to an operating phase of the motorized module 60, the wet clutch 90 configured in its engaged position couples the connection shaft 71 to the intermediate shaft 26 when the dog clutch 80 is in the second operating state.

[0092] According to another operating phase of the motorized module 60, the wet clutch 90 configured in its sliding position under torque slows down the intermediate shaft 26 relative to the protective casing 62 when the dog clutch 80 is in the first operating state.

[0093] In order to alternately switch from a first operating state to a second operating state, the dog clutch 80 of the connection device 70 comprises a sliding dog sleeve 82 mounted to slide axially on the connection shaft 71 and which comprises internal axial splines 83 adapted to mesh with a pinion 71b made of the same material as the connection shaft 71. The pinion 71b comprises in particular external axial splines 71a which cooperate with the sliding dog sleeve 82. The dog clutch can be actuated using an actuating fork 5 represented partially or directly by an electric actuator. The actuating fork 5 comprises in particular arms which engage in an annular groove formed on the external periphery of the sliding dog sleeve 82.

[0094] In a neutral operating phase of the dog clutch 80, the sliding sleeve 82 completely covers the external axial splines 71a of the connection shaft 70 without meshing with the output pinion 108 of the speed reducer and the protective casing 62. In this neutral operating phase, there is complete disconnection of the motorized module 60 with the gearbox 18 of the hybrid transmission assembly.

[0095] As illustrated in [Fig.2], the sliding sleeve 82 for dog clutching has a substantially cylindrical shape around the main axis X. A first axial end 84 of the sliding sleeve is shaped into a first series of sliding splines 84a capable of meshing with the protective casing 62 and a second axial end of the sliding sleeve 85 is shaped into a second series of sliding splines 85a capable of meshing with the output pinion 108 of the speed reducer.

[0096] In a complementary manner, the output pinion 108 of the speed reducer comprises a series of axial dog teeth 108a oriented radially outwards and arranged to cooperate with the second series of sliding gear splines. 85a. Similarly, the protective casing 62 comprises a series of teeth 62a carried by a crown 63 and arranged to cooperate with the first series of sliding gear splines 84a. The crown 63 is here attached to an inner face of the protective casing 62.

[0097] In this first embodiment, the first series of slider splines 84a and the second series of slider splines 85a are contiguous and axially aligned to form a single set of internal axial splines of the slider sleeve.

[0098] In order to ensure good centering between the components constituting the connection device 70, the output pinion 108 of the speed reducer guides the connection shaft 71 in rotation by means of a guide bearing 110 arranged axially at least partially within the dog clutch 80.

[0099] A control unit (not shown) makes it possible to control the reversible electric machine 61 and the connection device 70. To this control unit are connected sensors for measuring the speed of revolution of the intermediate shaft 26 and for measuring a characteristic speed of revolution of the reversible electric machine 61, which may be a speed of the output shaft of the reversible electric machine 61 or a speed of revolution of an element of the associated speed reducer 100. This control unit may be integrated into a robotic control of the gearbox 18 which controls the opening and closing of the synchronizers 41, the dog mechanisms 50, 52, and where appropriate the clutch mechanism 20 operating dry, to respond to a torque or speed setpoint.

[0100] As illustrated in [Fig.l], the motorized module 60 further comprises a protective casing 62 for housing the speed reducer 100 and the connection device 70. In this example, the reversible electrical machine 61 is fixed to the protective casing 62. The reversible electrical machine 61 has an axis of revolution parallel to the axis of revolution of the connection interface 64 and distant from the axis of revolution of the connection interface 64.

[0101] The motorized module 60 is preferably arranged outside the main cavity 22 of the gearbox housing 24, which makes it possible to offer this subassembly as optional equipment on a conventional gearbox.

[0102] Optionally, the hybrid transmission assembly 1 may comprise a power take-off member 65, capable of being driven at least by the reversible electric machine as can be seen in [Fig.l]. The power take-off member 65 is integrally connected in rotation to the output pinion 108 of the speed reducer, the power take-off member being coaxial with the connection shaft 71.

[0103] As an illustration, a reversible electric machine 61 can be provided powered at a nominal voltage of 48 volts, with the possibility of choosing between two reduction ratios between the output of the rotor of the electric machine and the connection device 70, depending on whether one wishes to favor a high torque or a high rotation speed at the output of the speed reducer 100. For this, the speed reducer 100 comprises:

[0104] - a drive shaft 101 supporting drive toothed wheels Z2, Z4, Z6 capable of being driven by the output shaft of the reversible electric machine;

[0105] - a complementary shaft 102 capable of being driven by complementary toothed wheels Z3, Z5, Z7, each drive gear wheel being kinematically linked to a corresponding complementary gear wheel so as to form a gear pair; and

[0106] - the output pinion 108 of the speed reducer kinematically linked with the shaft complementary ;

[0107] In this speed reducer, the drive shaft 101 comprises a drive toothed wheel Z2 meshing with the output pinion of the rotor of the reversible electric machine 61. The output pinion 108 of the speed reducer is meshed with the complementary toothed wheel Z7 of the complementary shaft 102. The drive and complementary shafts 101, 102 are coaxial with the output shaft of the reversible electric machine 61 with rotation axis R.

[0108] The change of gear ratio within the motorized module is carried out using a coupling device 120 arranged between the drive toothed wheels Z4, Z6 and the complementary toothed wheels Z3, Z5.

[0109] To obtain a first reduction ratio RI, a first pair of gears Z5, Z6 is selected by axially moving a coupling member of the coupling device 120 from a neutral position. The first reduction ratio RI of the first gear train may be between 4 and 6 in order to allow the synchronization of one of the secondary gears with the secondary shaft 16 of the gearbox 18 when the dry-operating clutch mechanism 20 is in the disengaged operating position combined with the wet clutch 90 configured in its engaged position and the dog clutch 80 being in the second operating state.

[0110] This first reduction ratio RI makes it possible to envisage several operating modes of the hybrid transmission assembly 1.

[0111] A first use is for the transient phases of changing the gear ratio of the gearbox 18. During these transient phases, the reversible electric machine 61 makes it possible to adapt the speed of revolution of the intermediate shaft 26 to the synchronization requirements during the switching of the dog mechanisms 50, 52 or the synchronizers 41, the electric machine being able to be used alternately. as an electric motor to increase the speed of revolution of the intermediate shaft 26 or as an electrodynamic brake to reduce this speed. This adaptation of the speed of the intermediate shaft 26 makes it possible to reduce the dog clutch or synchronization times, without having to resort to a gearbox brake.

[0112] However, during transient phases, when a gear ratio is engaged within the gearbox 18, the reversible electric machine 61 can be used in a current “generator” mode, to recharge a battery of the vehicle, or to modulate the slowing down of the transmission kinematic chain when the main thermal engine 14 of the vehicle enters an engine braking regime. The reversible electric machine 61 can be used in a “regenerative” mode to recharge the battery with free energy, when descending or during deceleration. Still when a gear ratio is engaged within the gearbox 18, the electric machine 6 1 powered by a battery of the vehicle, can be used in an “engine torque assistance” mode for an additional power supply for the traction of the vehicle.

[0113] Occasional use of the reversible electric machine 61 for purely electric traction of the vehicle can also be envisaged by opening the clutch 20 or the synchronizers 41 to decouple the main motor 14 or the primary shaft 12, while keeping one of the dog mechanisms 50, 52 engaged.

[0114] According to another mode of operation of the hybrid transmission assembly 1, when the wet clutch 90 is in the engaged position and the dog clutch 80 is in the second operating state, the main engine 14 of the vehicle can be used, if necessary in conjunction with the reversible electric machine 61, to drive the power take-off member 65.

[0115] In the case where a high-power reversible electric machine is used, for example an electric machine supplied with a nominal voltage of between 300 Volts and 800 Volts, the reversible electric machine 61 can be used in a purely electric traction mode of the vehicle. In such an operating mode, the dry-operating clutch mechanism 20 is in the disengaged operating position.

[0116] To obtain a second reduction ratio R2, a second pair of gears Z3, Z4 is selected by axially moving a coupling member of the coupling device 120 from a neutral position. The second reduction ratio R2 of the second gear train may be between 8 and 12 in order to allow the main engine to be started by the torque supplied by the reversible electric machine 61 when the dry-operating clutch mechanism 20 is in the combined engaged operating position with the wet clutch 90 configured in its engaged position and the dog clutch 80 being in the second operating state. operation.

[0117] This second reduction ratio R2 makes it possible to envisage a particularly advantageous operating mode of the “start-stop” type in which the main motor 14 automatically cuts out when the vehicle is stationary, and when the driver wants to start off again, he only has to press the accelerator pedal for the engine to restart. The main motor 14 is restarted via the high torque available at the end of the speed reducer 100 with a low rotation speed. This second reduction ratio R2 also applies to the “freewheeling” mode when the vehicle is momentarily rolling on its inertia, without the need for engine braking and in which the main motor 14 automatically cuts out. When the driver wants to accelerate, the main motor 14 is restarted via the high torque available at the end of the speed reducer 100 with a low rotation speed.

[0118] The coupling device 120 also includes a neutral position in which neither of the first nor second gear trains is rotated.

[0119] The connection device 70 can also be used to interrupt the connection between the intermediate shaft 26 and the reversible electric machine 61 when the latter is not useful, so as to limit the drag torque of the electric machine 61 and to reduce fuel consumption.

[0120] We will now describe in more detail the operating phases of the connection device 70 for which the dog clutch 80 is in the first operating state. As a reminder, the first operating state occurs when the dog clutch sliding sleeve 82 engages the series of teeth 62a carried by the crown 63 of the protective casing 62. The crown 63 is made directly from the protective casing. In this case, the torque output disc holder 93 is fixed in rotation relative to the protective casing 62.

[0121] The wet clutch 90 is then controlled in sliding under torque by applying a pressure within the pressure chamber 97 sufficient to bring the discs 91a, 91b of the multi-disc assembly into contact without completely blocking the rotation of the torque input disc carrier 92. Thus, it is possible to slow down the intermediate shaft 26 relative to the protective casing 62. The connection device 70 then acts as a gearbox brake without stressing the reversible electric machine 61. This operating phase may in particular be used in the event of failure of the reversible electric machine 61 or when the battery 43 associated with the reversible electric machine 61 has reached its maximum charge so that the use of this electric machine to brake the intermediate shaft 26 would risk damaging the battery 43.

[0122] Also, the wet clutch 90 can be controlled in slippage under torque, during the transient phases of gear change of the gearbox 18, to brake the intermediate shaft 26.

[0123] In [Fig. 3] a second embodiment of the invention is illustrated, which differs from the previous one by the use of a hydraulically controlled multi-disc type wet clutch 90.

[0124] In this second embodiment, the torque output disc holder 93 and the connection shaft 71 form two half-casings fixed to each other and together defining an internal space in which a multi-disc assembly 91 is housed which is intended to transmit the torque between the connection shaft 71 and the intermediate shaft 26.

[0125] The multi-disc assembly 91 comprises a plurality of annular discs 91a, made of steel for example, which are integral in rotation with the torque output disc holder 93 and mounted to slide axially relative to the latter. To do this, each disc 91a comprises on its external periphery an external toothing which is engaged with the internal toothing formed inside a cylindrical skirt of one of the half-casings 93, 71. The multi-disc assembly further comprises a plurality of friction discs 91a which are interposed between the discs 91b. The friction discs 91a are integral in rotation with the torque input disc holder 92 with axial translation freedom. To do this, the torque input disc holder 92 has external teeth and each friction disc 91a has, on its internal periphery, internal teeth which are engaged with the corresponding external teeth.Each friction disc 91a has friction linings arranged on each of its faces, front and rear.

[0126] Furthermore, the actuating piston 96 is mounted axially movable inside the internal space of the connection shaft 71. The actuating piston 96 comprises, on its external periphery, a seal 99 which cooperates in a sealed manner with the cylindrical skirt of the half-casing 71 so as to define a pressure chamber 97 with variable volume between the actuating piston 96 and the bottom 71d of the half-casing 71. Furthermore, the bottom 71d of the half-casing 31 has a channel 71e, visible in [Fig. 3], which is connected to a hydraulic circuit equipped with a pump, not shown, by means of a channel 62c formed in the protective casing 62.

[0127] As illustrated in [Fig.3], a portion 62b of the protective cover is axially interposed between the wet clutch 90 and the dog clutch 80, the portion 62b being a wall made from the same material as the protective cover in which the channel 62c is formed.

[0128] When the variable volume pressure chamber 97 is supplied with pressurized fluid, the actuating piston 96 moves towards the multi-disc assembly so that the friction discs 91a are pinched between the discs 91b and that the torque is thus transmitted between the connecting shaft 71 and the intermediate shaft 26.

[0129] Conversely, when the hydraulic fluid is expelled from the variable volume pressure chamber 97, the actuating piston 96 moves away from the multi-disc assembly so that the friction discs 91a and the discs 91b return to a disengaged position in which they are axially spaced apart from each other.

[0130] In this second embodiment, the connection device 70 uses the architecture described in the first embodiment of the invention.

[0131] Naturally, the examples shown in the figures and discussed above are given for illustrative purposes only and are not limiting. It is explicitly provided that the different embodiments illustrated can be combined with each other to propose others.

[0132] As indicated previously, the use of a second reversible electric machine is optional in all embodiments. The reduction gear train may be replaced by any other reduction mechanism, in particular an epicyclic train, or a belt or chain reduction mechanism. The input and output members of the reduction mechanism may be coaxial, parallel or in another orientation. The axis of revolution of the rotor of the reversible electric machine may be coaxial with the axis of revolution of the intermediate shaft, or parallel and at a distance from the axis of revolution of the intermediate shaft or in another orientation. The reversible electric machine 61 is preferably integrated into the protective casing of the motorized module but may alternatively be attached to the protective casing.

[0133] All of the embodiments according to the invention have the following advantages:

[0134] - The position of the motorized module 60 within the hybrid transmission assembly 1 optimizes gearshift speed management within the gearbox. For upshifting, the 48-volt powered 60 motorized module replaces the conventional intermediate shaft brake disclosed in EPI592590 AL. For downshifting, the motorized module accelerates the intermediate shaft. To enable fast and efficient synchronization of the gearbox dog clutches, double declutching is no longer necessary. Gearshift time is reduced by 35%.

[0135] - The “regenerative” mode allows the battery to be recharged with free energy, downhill or during deceleration.

[0136] - The current "generator" mode can be used at any time to recharge the battery with energy from the internal combustion engine.

[0137] - The “engine torque assistance” mode optimizes the operation of the engine at internal combustion, in particular by reducing the rotation speed over the range of speed operated by the internal combustion engine.

[0138] - The “start-stop” mode in the starting phase or the “wheel forward” mode free” is available without using a standard starter.

[0139] All these different operating modes are available thanks to the connection device 70 according to the invention with reduced operating times.

Claims

Claims

1. Motorized module (60) for driving and slowing down an intermediate shaft of a hybrid transmission assembly, said motorized module comprising: - at least one reversible electric machine (61) attached to a protective casing (62), - a connection device (70) arranged to connect the at least one reversible electric machine (61) to the intermediate shaft (26), and - a speed reducer (100) arranged kinematically between the at least one reversible electric machine and the connection device (70), the connection device (70) comprising: - a connection shaft (71) movable in rotation relative to the protective casing (62) along a main axis (X), - a dog clutch (80) supported by the connecting shaft and arranged to lock the connecting shaft (71) in rotation with the protective casing in a first operating state or to couple the connecting shaft (71) in rotation with an output pinion (108) of the speed reducer (100) in a second operating state, and - a wet clutch (90) of the multi-disc type kinematically linked to the connecting shaft (71) comprising: - a torque input disc carrier (92) partially supporting a multi-disc assembly (91) and arranged to be rotationally connected to the intermediate shaft (26), and - an actuation system (95) for configuring the wet clutch (90) in either an engaged position, a disengaged position, or a torque slip position, and wherein the wet clutch (90) configured in its engaged position couples the connecting shaft (71) to the intermediate shaft (26) when the dog clutch (80) is in the second operating state, or the wet clutch (90) configured in its torque slip position slows the intermediate shaft (26) relative to the protective housing (62) when the dog clutch (80) is in the first operating state.

2. Motorized module (60) according to claim 1, in which the multi-disc assembly (91) of the wet clutch is pressed axially by an actuating piston (96) of annular shape, coaxial with the connecting shaft (71), the actuating piston (96) being guided axially within a pressure chamber (97) formed directly or indirectly in the protective casing (62).

3. Motorized module (60) according to claim 1 or 2, in which the dog clutch (80) comprises a sliding dog clutch sleeve (82) mounted to slide axially on the connection shaft (71) and which comprises internal axial splines (83) adapted to mesh with external axial splines (71a) of the connection shaft (71).

4. Motorized module (60) according to the preceding claim, in which the sliding sleeve (82) for dog clutching has a substantially cylindrical shape around the main axis (X), a first axial end (84) of the sliding sleeve is shaped into a first series of sliding splines (84a) capable of meshing with the protective casing (62) and a second axial end (85) of the sliding sleeve is shaped into a second series of sliding splines (85a) capable of meshing with the output pinion (108) of the speed reducer (100).

5. Motorized module (60) according to claim 4, wherein the output pinion (108) of the speed reducer (100) comprises a series of axial dog teeth (108a) oriented radially outwards and arranged to cooperate with the second series of sliding gear splines (85a).

6. Motorized module (60) according to claim 4 or 5, in which the protective casing (62) comprises a series of teeth (62a) carried by a crown (63) and arranged to cooperate with the first series of sliding gear splines (84a), said crown (63) is carried or attached to an inner face of the protective casing (62).

7. A motorized module (60) according to one of claims 4 to 6, wherein the first series of slider splines (84a) and the second series of slider splines (85a) are contiguous and axially aligned to form a single set of internal axial splines (83) of the slider sleeve (82).

8. Motorized module (60) according to one of the preceding claims, in which the wet clutch (90) of multi-disc type comprises a torque output disc carrier (93) linked in rotation with the shaft of connection (71) by groove, by hooping or by screwed assembly.

9. Motorized module (60) according to the preceding claim, in which the wet clutch (90) of multi-disc type comprises a multi-disc assembly (91) consisting of a first set of discs (91a) engaged with splines of the torque input disc carrier (92), and a second set of discs (91b) engaged with splines of the torque output disc carrier (93).

10. Motorized module (60) according to one of the preceding claims, in which a portion (62b) of the protective cover (62) is interposed axially between the wet clutch (90) and the dog clutch (80), the portion being for example a wall made from the same material as the protective cover or a support plate attached to the protective cover (62).

11. Motorized module (60) according to one of the preceding claims, wherein the speed reducer (100) comprises: - a drive shaft (101) supporting drive toothed wheels (Z2, Z4, Z6) capable of being driven by the output shaft of the reversible electric machine; - a complementary shaft (102) capable of being driven by complementary toothed wheels (Z3, Z5, Z7), each drive toothed wheel being kinematically linked to a corresponding complementary toothed wheel so as to form a pair of gears; and - the output pinion (108) of the speed reducer kinematically linked with the complementary shaft;wherein a coupling device (120), arranged between the drive gears (Z4, Z6) and the complementary gears (Z3, Z5), selects a first pair of gears (Z5, Z6) to obtain a first reduction ratio (R1) or a second pair of gears (Z3, Z4) to obtain a second reduction ratio (R2) from a neutral position.;

12. Hybrid transmission assembly (1) for driving a vehicle, comprising: • a dry-operating clutch mechanism (20) intended to be driven by a main engine (14) of the vehicle; • a friction clutch disc (21) with a primary rotation axis (XI) capable of being driven by the main engine depending on the engaged or disengaged operating position of the clutch mechanism; a gearbox (18) comprising: • one or more primary toothed wheels (38, 40) driven in rotation by the friction clutch disc along the primary axis of rotation (XI), • a secondary shaft (16) intended to drive a set of one or more drive wheels of the vehicle, • several secondary gear wheels (42, 44, 46) capable of being coupled to the secondary shaft (16), • an intermediate shaft (26) to which intermediate gear wheels (28, 30, 32, 34, 36) are rotationally secured, the primary gear wheel(s) (38, 40) and the secondary gear wheels (42, 44, 46) each meshing permanently with a corresponding gear wheel among the intermediate gear wheels (28, 30, 32, 34, 36), and the motorized module (60) according to any one of the preceding claims in which the torque input disc holder (92) is attached to the intermediate shaft (26) coaxially, and in which the at least one reversible electric machine (61) drives the intermediate shaft (26) in rotation when the wet clutch (90) is configured in its engaged position and when the dog clutch (80) is in the second operating state.

13. Hybrid transmission assembly (1) according to the preceding claim, wherein the speed reducer (100) comprises a first gear train connecting the reversible electric machine (61) to the output pinion (108) via a first reduction ratio (RI) by actuating a coupling device (120) according to a first position and a second gear train connecting the reversible electric machine (61) to the output pinion (108) via a second reduction ratio (R2) by actuating the coupling device (120) according to a second position.

14. A hybrid transmission assembly (1) according to claim 13, wherein the second reduction ratio (R2) of the second train gear ratio is between 8 and 12 to allow the main engine to be started by the torque supplied by the reversible electric machine (61) when the dry operating clutch mechanism (20) is in the combined engaged operating position with the wet clutch (90) configured in its engaged position and the dog clutch (80) being in the second operating state.

15. A hybrid transmission assembly (1) according to claim 13 or 14, wherein the first reduction ratio (RI) of the first gear train is between 4 and 6 in order to allow synchronization of one of the secondary gears (42, 44, 46) with the secondary shaft (16) when the dry operating clutch mechanism (20) is in the disengaged operating position combined with the wet clutch (90) configured in its engaged position and the dog clutch (80) being in the second operating state.

16. Hybrid transmission assembly (1) according to one of claims 12 to 15, in which a power take-off member (65) is connected in rotation to the output pinion (108) of the speed reducer (100), the power take-off member (65) being coaxial with the connection shaft (71).

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