Hybrid Transmission with a Biased Motor

Abstract

A hybrid transmission for a motor vehicle, the motor vehicle being provided with a combustion engine (1) and an offset electric traction machine (2) on the same line, the hybrid transmission comprising two concentric main shafts (3, 4), a countershaft (5) and a transfer shaft (6), the two concentric main shafts being respectively connected to the combustion engine and the electric machine (2) without a disconnect clutch, the countershaft being connected to the vehicle wheels by a differential (7), the transfer shaft being for transmitting the movement of the main shaft (3) to the countershaft (5) and for coupling these main shafts (3, 4), characterized in that the hybrid transmission only comprises three main idler gears (8, 9, 10) associated with the combustion engine (1) and at least one main gear (14) attached to the main shaft (4) connected to the electric traction machine (2), wherein the first two idler gears (8, 9) rotate around the main shaft (3) connected to the combustion engine, and the third idler gear (10) rotates around the transfer shaft (6).

Description

Field of the Invention

[0001] The present invention relates to the field of hybrid transmissions for motor vehicles, which motor vehicles comprise on the one hand a combustion engine and on the other hand an electric machine.

[0002] More specifically, the subject of the present invention is a hybrid transmission for a motor vehicle provided with a combustion engine and an electric traction machine offset on the same line, the hybrid transmission comprising two concentric main shafts, a countershaft and a transfer shaft, the two concentric main shafts being connected respectively to the combustion engine and the electric machine without a disconnect clutch, the countershaft being connected to the vehicle wheels by means of a differential, and the transfer shaft serving to transmit the movement of the main shafts to the countershaft and to couple the main shafts. Background Art

[0003] The published document FR 3 022 495 discloses a hybrid transmission with an offset electric machine, the hybrid transmission comprising two concentric main shafts, the two concentric main shafts comprising a solid main shaft connected to an internal combustion engine ICE, and a hollow main shaft connected to an offset electric machine EM at the opposite end of the transmission. The transmission comprises a countershaft supporting differential drive gears. The transmission also comprises a transfer shaft permanently connected to the solid main shaft. The transfer shaft transmits the movement of the main shafts to the countershaft at a certain transmission ratio, but does not directly drive the differential.

[0004] Reference Figure 1 states that the "electric traction structure" of this first transmission consists of two electric transmission ratios EV1 and EV2 provided by the meshing of two "electric fixed gears" of the hollow main shaft with two "electric idle gears" rotating on the countershaft.

[0005] The "combustion engine traction structure" of this first transmission consists of four combustion engine transmission ratios ICE1, ICE2, ICE3 and ICE4 associated with two idle gears of the combustion engine main shaft and two idle gears of the transfer shaft. The transmission ratios ICE2 and ICE4 descend directly from the main line on two fixed gears of the countershaft. The transmission ratios ICE1 and ICE3 use the transfer shaft and descend again on the countershaft through the gears of the transmission ratio EV2 or ICE4. Finally, the transmission receives torque from a second electric machine HSG, which torque descends on the transfer shaft via a connecting gear train.

[0006] The transmission has two electric transmission ratios EV1 and EV2, and four combustion engine transmission ratios ICE1, ICE2, ICE3 and ICE4.

[0007] These transmission ratios, and their hybrid combinations, make it possible to adapt the traction motor to optimize the overall energy performance.

[0008] However, during the acceleration process, the change between the two electric transmission ratios EV1 and EV2 means an interruption of torque, which is unpleasant for some users accustomed to the customary comfort of automatic transmissions without torque interruption (such as dual-clutch transmissions or continuously variable transmissions (CVT) or single-ratio electric vehicles). Summary of the Invention

[0009] The present invention aims to benefit from the increase in the battery's charge storage capacity and the improvement of the motor's performance in order to overcome the drawbacks of known transmissions. The present invention enables the transmission to avoid the criticism related to the above-mentioned discomfort, which is mainly related to the poor quality of certain gearshifts.

[0010] Accordingly, the proposed transmission only includes three main idler gears associated with the combustion engine and at least one main gear fastened to the main shaft connected to the electric traction machine. Among the three main idler gears, the first two gears rotate around the main shaft connected to the combustion engine, and the third gear rotates around the transmission shaft.

[0011] In the first embodiment, the third idler gear meshes with a fixed gear on the main shaft connected to the electric traction machine.

[0012] In the second embodiment, the third idler gear meshes with one of the first two idler gears.

[0013] Thanks to these modifications, the increased compactness of the motor can be utilized to improve, on the one hand, the performance of the transmission in terms of efficiency and quality, and on the other hand, the quality of gearshifts. With the present invention, it is also possible to limit the number of gearshifts by eliminating the lower combustion engine transmission ratio and the second electric transmission ratio. Brief Description of the Drawings

[0014] The present invention will be better understood by reading the following description of non-limiting embodiments of the invention with reference to the accompanying drawings, in which:

[0015] - Figure 1 A previously known transmission is shown,

[0016] - Figure 2 A first embodiment of the present invention is shown,

[0017] - Figure 3 Its transverse arrangement is shown,

[0018] - Figure 4 Is the matrix of its parallel combustion and electric hybrid kinematic model,

[0019] - Figure 5 Its series hybrid mode is shown,

[0020] - Figure 6Shows its electric - combustion connection structure,

[0021] - Figure 7 Shows its electric connection structure,

[0022] - Figure 8 Shows its hybrid traction structure,

[0023] - Figure 9 Shows the use of the transmission on a rechargeable hybrid vehicle,

[0024] - Figure 10 Shows its use on a non - rechargeable hybrid vehicle,

[0025] - Figure 11 Shows the second embodiment of the present invention,

[0026] - Figure 12 Relates to its electric - combustion connection structure,

[0027] - Figure 13 Relates to its electric connection structure,

[0028] - Figure 14 Relates to its shaft - lowering structure, and

[0029] - Figure 15 and Figure 16 Shows its use on a rechargeable hybrid vehicle (PHEV) or a non - rechargeable hybrid vehicle (HEV). Detailed Description

[0030] Figure 1 The hybrid transmission for a motor vehicle provided with a combustion engine 1 and a drive motor 2 comprises two concentric main shafts 3, 4 which are connected without a disengaging clutch to the crankshaft (not shown) of the combustion engine 1 (ICE) and to the main electric traction machine 2EM. The hybrid transmission comprises a countershaft 5 and a transfer shaft 6 which is connected to the vehicle wheels via a differential 7, the transfer shaft being for transmitting the movement of the solid main shaft 3 to the countershaft 5 and for coupling the main shafts 3, 4. The solid main shaft 3 is connected to the front end of the crankshaft 1a of the combustion engine ICE via a filtering system 21 (vibration - damping hub, dual - mass flywheel DMF or similar element). The transmission is also coupled to a second electric machine 16HSG which is connected to the transfer shaft 6 via an intermediate gear 19a.

[0031] This transmission has three couplings:

[0032] - The first coupling C2 - 4Th enables the engagement of the first combustion - engine gear ratio ICE2 and the fourth combustion - engine gear ratio ICE4 on the main line,

[0033] - The second connector C1-2EV enables two electric transmission ratio gears EV1, EV2 to be joined on the secondary line, and

[0034] - The third connector C1-3Th enables the first combustion engine transmission ratio ICE1 and the third combustion engine transmission ratio ICE3 to be joined on the transmission shaft.

[0035] Figure 2 The same arrangement is shown again in part. Also involved is a hybrid transmission for a motor vehicle, which is provided with a combustion engine 1 and an electric traction machine 2 offset on the same line. The hybrid transmission includes: two concentric main shafts 3, 4; a secondary shaft 5; and a transmission shaft 6. The two concentric main shafts are respectively connected to the combustion engine and the electric machine 2 without a disconnect clutch. The secondary shaft is connected to the vehicle's wheels through a differential 7. The transmission shaft is used to transmit the movement of the main shaft 3 to the secondary shaft 5 and to join the main shafts 3, 4.

[0036] However, the driveline has developed quite significantly. The new transmission only includes three main idler gears 8, 9, 10 associated with the combustion engine 1. The first two main idler gears 8, 9 rotate around the main shaft 3 connected to the combustion engine 1 ICE. They each enable the establishment of combustion engine transmission ratios ICE2, ICE4, which are "mixable" by combining with the electric transmission ratio EV1. The third idler gear 10 rotates around the transmission shaft 6. Two main gears 11, 14 are fastened to the hollow shaft 4 connected to the electric machine EM. Only the fixed main gear 14 (meshing with the secondary idler gear 12) is dedicated to the pure electric mode of the transmission ratio EV1. The second idler gear 13 on the secondary shaft 5 facing the first idler gear is only dedicated to the hybrid mode Hyb3.

[0037] In two non-limiting embodiments of the present invention described, the transmission can be connected to a second electric machine 16 HSG, the output shaft 18 of which descends on the transmission shaft 6 so as to be able to accumulate its torque together with the torque of the combustion engine. The second electric machine 16 enables a series hybrid mode to be provided, in which the combustion engine 1 drives the secondary electric machine 16 in generator mode so as to generate electrical energy that can be used by the electric traction machine EM to move the vehicle.

[0038] In Figure 2 the third idler gear 10 dedicated to the combustion engine transmission ratio meshes with the fixed gear 11 of the main shaft 4 connected to the traction machine 8. It is possible to establish a hybrid mode on two different combustion engine transmission ratios ICE1 and IC3, especially to establish the mode "Hyb3", which benefits from the reduction by half of the combustion engine transmission ratio ICE3. The transmission shaft 6 carries a fixed gear 20 meshing with the main fixed gear 3a.

[0039] Two idler gears 12, 13 of the secondary shaft 5 mesh with two fixed gears 11, 14 of the hollow main shaft 4 in order to establish an electric transmission ratio EV1 and a combustion engine transmission ratio ICE1, or a hybrid mode Hyb3. When the third idler gear 10 is engaged, the combustion engine torque drops on the hollow main shaft 4. If gear 12 is engaged simultaneously with gear 10, the doubling reduction of the combustion engine torque corresponds to the doubling reduction of the first combustion engine transmission ratio ICE1. This transmission ratio can be hybridized by combining with the electric transmission ratio EV1. In contrast, if gear 13 is engaged on its shaft, the mode Hyb3 is engaged with the third combustion engine doubling reduction transmission ratio ICE3.

[0040] Figure 3 The sectional view of Figure 2 shows the spatial arrangement of the lines of the shaft of and the lines of the gears. From left to right, the line of the differential 7, the line of the secondary shaft 5 can be seen, and then the main line of the combustion engine idler gear 9 with the maximum diameter for the combustion engine transmission ratio ICE4; above the main line, on the left is the transfer line 6, and on the right is the line of the intermediate gear 9 towards the line 18 of the electric machine 16 HSG.

[0041] The proposed new hybrid transmission has eight traction modes:

[0042] - Electric traction mode at the electric transmission ratio EV1,

[0043] - Two combustion engine traction modes at the transmission ratios ICE2 and ICE4, and

[0044] - Five hybrid modes: The first parallel mode “Hyb11” accumulates the torque of the combustion engine at the transmission ratio ICE1 and the electric transmission ratio EV1; the second parallel mode “Hyb3” combines the torque of the electric machine EM with the torque of the combustion engine gears ICE1 - 3 under the gear Hyb3; the third parallel mode “Hyb21” accumulates the torque of the second combustion engine transmission ratio and the torque of the electric transmission ratio; the fourth parallel mode “Hyb41” accumulates the torque of the fourth combustion engine transmission ratio and the torque of the electric transmission ratio; and finally, the series hybrid mode “e - drive 1”, in which the combustion engine supplies energy to the traction machine EM by rotating the second electric machine HSG in the generator mode. In these four parallel hybrid modes, the power of the secondary electric machine HSG 16 can be accumulated with the power of the combustion engine.

[0045] The torque flow established in each of these modes is detailed in Figure 4 :

[0046] - At the top on the left side, the engagement transmission ratio EV1: on the left side is the coupler C1-2EV, the couplers C2-4Th and C1-3Th are in neutral,

[0047] - In the first row, there are three hybrid transmission ratios: mode EV1+ICE1-3, on the left side is the coupler C1-2EV, and the coupler C1-3Th3 is engaged; mode EV1+ICE2, on the left side is the coupler C2-4Th; mode EV1+ICE4, on the right side is the coupler C2-4Th,

[0048] - In the second row, the coupler C1-2EV is in neutral: according to the position of C2-4Th, there are two transmission ratios in the combustion engine mode, IC2 and ICE4,

[0049] - In the third row, the hybrid mode Hyb3: the coupler C2-4Th is in neutral, on the right side is the coupler C1-2EV, and the coupler C1-3Th is engaged.

[0050] Figure 5 The series hybrid mode is shown, in which the combustion engine rotates the motor HSG in the generator mode, and the motor EM itself provides the traction for the vehicle.

[0051] The "combustion-electric connection structure" (HSG-ICE) of the transmission is shown in Figure 6 It. This connection structure consists of three lines of shafts, which kinematically connect the auxiliary motor HSG to the combustion engine ICE:

[0052] - The input shaft 18 of the motor HSG,

[0053] - The connecting shaft 17, and

[0054] - The solid main shaft 3, on which a fixed gear 3a is assembled.

[0055] The solid main shaft 3 also supports the DMF 21 and the coupling system C2-4Th of the idle gears I8 and 9. The connection structure HSG-ICE also meshes with the transmission shaft 6 via the main gear 3a, and the main gear meshes with the gear 17a of the connecting shaft 17 connected to the gear 18a to ensure the synchronization with the idle gear ICE1-3, disengaging the engagement assistance and the "boost" function by means of the coupling system C1-3Th.

[0056] This structure ensures the following functions:

[0057] - Starting the combustion engine ICE via the electric motor HSG through a triple gear set ("triplet") 18a, 17a, 3a (instead of the quadruple gear set in the previous architecture),

[0058] - By means of the HSG, synchronize the rotational speed of the combustion engine ICE with the rotational speed of the idler gear engaged at each transmission ratio.

[0059] - Eliminate the inertial torque through the auxiliary motor HSG to assist in disengaging the gears.

[0060] - Ensure the "boost" function of the driving demand by inputting additional torque at the engaged transmission ratio through the second motor HSG and immediately inputting the vehicle's acceleration during the rapid depression of the accelerator pedal.

[0061] - Recharge the battery using the available combustion engine torque that is not useful for towing the vehicle to rotate the motor (HSG) in generator mode; in this case, the power is transmitted through the triple gear set via shafts 3, 17, 18 (improving the efficiency of the transmission compared to the quadruple gear set of the previous transmission), and

[0062] - Limit the impact torque level during sudden blockage of the powertrain through peak torque limitation by the DMF 21.

[0063] The "electric traction structure" of the transmission is shown in Figure 7 The hollow main shaft 4, which is connected to the motor EM and concentric with the solid shaft 3, carries two fixed gears:

[0064] - The fixed gear 14 of the electric transmission ratio EV1 engages with the first idler gear 12 of the countershaft 5, and

[0065] - The fixed gear 11 in the triple gear set 10, 11, 13 allows two hybrid modes Hyb11 and Hyb3 to be engaged.

[0066] The two idler gears 12 and 13 are "engageable" on their shaft 5 by means of the coupling system C1EV-H3. The total reduction ratio of approximately 10 at the transmission ratio EV1 enables ensuring a good performance level for "starting" from a standstill, with an acceleration of 1 m / s 2 on a 12% slope and a maximum operating speed Vmax ≥ 130 kilometers per hour (km / h) at 12,000 revolutions per minute (rpm) of the motor EM. The electric traction structure ensures the following functions:

[0067] - The vehicle starts from a stationary state in all reasonably foreseeable slope, grip, and vehicle mode conditions.

[0068] - Depending on the available energy in the battery and the depression of the accelerator pedal, the vehicle is towed at a maximum of approximately 130 km / h in pure electric or hybrid mode (inputting combustion engine torque).

[0069] Refer to Figure 8, the "hybrid traction structure" of the transmission is as follows:

[0070] - The first hybrid mode Hyb1-1 is obtained by engaging the gear ICE1-3 with the sliding sleeve C1-3Th and engaging the gear EV1 with the sliding sleeve CEV1-H3, and

[0071] - The hybrid mode Hyb3 is achieved by engaging the gear 10 with the sliding sleeve C1-3Th and engaging the gear 13 with the sliding sleeve CEV1-H3.

[0072] In the hybrid mode Hyb3, the torque of the combustion engine is reduced from the transmission shaft 6 on the countershaft 5 at the second combustion engine transmission ratio ICE3 through a triple gear set, which consists of the third idler gear 10, the fixed gear 11 connected to the main shaft 4 of the electric traction machine 2, and the idler gear 13 of the countershaft 5. Implementing the third combustion engine transmission ratio instead of the second electric transmission ratio of the known transmission enables the release of the reduction that can be achieved in the third combustion engine transmission ratio ICE3 and the fourth combustion engine transmission ratio ICE4, making them more flexible to adapt to the constraints of the dynamic performance and consumption of each vehicle. The "hybrid structure" of the transmission ensures the following functions:

[0073] - In the mode Hyb11, the traction of the vehicle on a steep slope, and

[0074] - In the mode Hyb3, the maximum moving speed of the vehicle is achieved by adding electric torque and combustion engine torque to ensure the maximum acceleration of the vehicle and achieve its maximum power Pmax.

[0075] The combination of these structures within the transmission enables gear shifting without torque interruption, for example, in the following two shift linkages:

[0076] - Hyb21->Hyb3 : Hyb21 -> ICE2 -> Hyb22 -> ZEV2 -> Hyb3, or

[0077] - ICE4->Hyb3 : ICE4 -> Hyb42 -> ZEV2 -> Hyb3.

[0078] Figure 9A preferred usage area for various different modes of a transmission is proposed in a non - limiting manner based on the depression and movement speed of an accelerator butterfly valve, and on a rechargeable vehicle PHEV, there are shift regions according to vehicle speed and accelerator pedal pressure: EV1 (electric transmission ratio), Hyb21 (hybrid ICE2 + EV1 at the second combustion engine transmission ratio), and Hyb41 at the fourth transmission ratio, with or without the addition of a second electric machine HSG. The transmission ratio Hyb3 can also benefit from the addition of the second electric machine HSG.

[0079] Figure 10 Similar indications are given for the case of a non - rechargeable hybrid vehicle HEV.

[0080] Figures 11 to 16 A second embodiment of the transmission is shown, which does not have its "first combustion engine transmission ratio" ICE1. The "electric - combustion connection" structure, "electric connection" structure, and shaft structure are different from the first embodiment.

[0081] The hollow shaft 4 connected to the electric tractor 2 carries a single fixed gear 14 that meshes with the idler gear 12 of the countershaft. The third idler gear 10 meshes with the gear 9 of the transmission ratio ICE4 (which itself meshes with the fixed gear 15 of the countershaft 5) in order to establish the combustion engine transmission ratio.

[0082] This reduction is adapted to benefit from the maximum torque of the electric machine at the speed that allows the combustion engine to ignite. As Figure 12 indicated, the "electric - combustion structure" consists of four lines that kinematically connect the electric machine HSG to the shaft of the combustion engine ICE:

[0083] - the input shaft 18 of the HSG 16,

[0084] - the connecting shaft 19,

[0085] - the transmission shaft 6, which is coupled through its fixed gear 20 to the system (combustion engine transmission ratio ICE3) that couples the idler gear 10, and

[0086] - the solid main shaft 3, which supports the vibration damping system (DMF) 21 and the system for coupling the idler gears 8 and 9 (combustion engine transmission ratios ICE2 and ICE4).

[0087] This structure has the following functions:

[0088] - starting the combustion engine ICE through the electric machine HSG,

[0089] - synchronizing the speed of the combustion engine ICE with the speed of the idler gear to be engaged by means of the HSG,

[0090] - Eliminate the inertial torque through the HSG to help the disengaging gear disengage,

[0091] - Input additional torque at the engaged transmission ratio through the HSG and recharge the battery by using the available combustion engine torque, which is not useful for vehicle traction when the HSG operates in the generator mode.

[0092] - Filter the non-cyclic behavior of the combustion engine ICE through the DMF 21, and

[0093] - Limit the impact torque in case of sudden blockage of the powertrain.

[0094] Reference Figure 13 As follows is the "electric connection structure" of the transmission. The electric transmission ratio EV1 is obtained from the fixed gear 14 of the hollow shaft 4 and the idler gear 12 of the countershaft 5; with the aid of the coupling system C1EV, the electric transmission ratio is "engageable". The total reduction ratio of approximately 10 at this transmission ratio enables ensuring a good performance level during vehicle start-up, where the acceleration under load on a 12% slope is 1 m / s 2 and the maximum speed is higher than 130 km / h at 12,000 revolutions per minute (rpm).

[0095] The connection structure ensures the following functions:

[0096] - Start the vehicle under all reasonably foreseeable slopes, grip and vehicle loads,

[0097] - According to the available energy in the battery and the depression of the accelerator pedal, the vehicle traction is up to approximately 130 km / h in pure electric mode or in hybrid mode (inputting the torque of the combustion engine).

[0098] In Figure 14 the corresponding "shaft drop structure" isolated is as follows:

[0099] - The combustion engine torque is transmitted from the combustion engine idler gears 8, 9, 10 to the transmission shaft,

[0100] - The torque is transmitted from the electric traction machine to the idler gear 12 of the transmission ratio EV1,

[0101] - The combustion engine and electric torques are transmitted to the wheels via the countershaft 5 and its drive gear 22. The countershaft 5 supports the fixed gears 23, 15 of the transmission ratios ICE4 and ICE2 and the coupling system C1EV for coupling the transmission ratio EV1; the countershaft 5 also ensures guiding the idler gear 12 of the transmission ratio EV1.

[0102] For Figure 15 the rechargeable hybrid vehicle PHEV or Figure 16of the HEV, Figure 15 and Figure 16 present a simplified (non - limiting) usage matrix that is used to use the transmission ratio based on the depression of the accelerator pedal and the speed of the vehicle.

[0103] In two non - limiting embodiments of the present invention described, the transmission has three idler gears associated with the combustion engine and a main transmission ratio that reduces the power of the electric motor by half. In the first embodiment, the second electric transmission ratio of the transmission is only used in the hybrid mode.

[0104] The combustion engine idler gear 10 arranged on the transmission shaft 6 connects the main combustion engine line and the main electric line. It allows for direct parallel hybridization at the outlets of the two traction sources (combustion engine ICE and electric motor EM). Its combination with the reduction of the main electric shaft (hollow shaft 4) produces a reduction corresponding to the first and third transmission ratios in the combustion engine powertrain.

[0105] The separation of the third transmission ratio ICE3 and the fourth transmission ratio ICE4 is achieved by adjusting the fourth transmission ratio to achieve perfect adjustment of the gearbox, so as to achieve the best consumption on the highway, while the third transmission ratio can be dedicated to the dynamic performance of the vehicle (maximum acceleration and maximum moving speed).

[0106] In the second embodiment described, the transmission does not have a second electric transmission ratio, nor an idler gear connecting the main electric line and the main combustion engine line. The third combustion engine transmission ratio is achieved through a triple gear set that passes through the idler gear of the fourth transmission ratio. This arrangement reduces the shaft volume and its mass of the transmission, while allowing for an efficiency gain. As long as there is no hybrid mode Hyb11, it is sufficient to convert the power of the combustion engine into electrical energy for electric traction in EV1, and this second embodiment shows its full benefits.

[0107] In the two embodiments described, the series hybrid mode "E - drive" enables optimization of the mechanical efficiency of the transmission by using the excess combustion engine torque to recharge the battery.

[0108] In the first embodiment ( Figures 2 to 8 ), the power is transmitted between the combustion engine ICE and the auxiliary motor HSG 16 via a triple gear set 18a, 17a, 3a between the solid main shaft 3, the intermediate shaft 17 (radially offset from the transmission shaft 6), and the shaft 18 of the auxiliary motor 16 in both directions. This arrangement simplifies the powertrain between the combustion engine and the auxiliary motor HSG, because the reduction between the two motors is the result of two meshes instead of three meshes, without passing through the transmission shaft.

[0109] In the second embodiment ( Figures 11 to 14) In this case, this transmission occurs through a four-speed gearset similar to Figure 1 that. In this regard, the architecture of the first embodiment of the transmission has higher performance than the architecture of the second embodiment.

[0110] Finally, the development of the driveline does not degrade the dynamic performance levels of the vehicle in terms of traction on slopes during "takeoff" and the maximum speed in electric mode. These modifications mainly consist of eliminating the second electric gear ratio EV2 and the first combustion engine gear ratio ICE1. They make it possible to optimize:

[0111] - The transmission efficiency obtained through a gain in the level of friction on the teeth and the friction of the idler gears on their shafts,

[0112] - The quality of engagement, and thus, the cost of the components and the autonomy of the vehicle,

[0113] - The overall quality of gearshifts, through the suppression of the gearshift EV1-EV2 and its "torque hole", a very perceptible suppression during urban and semi-urban operation in the new electric mode "without gearshifts".

Claims

1. A hybrid transmission for a motor vehicle, the motor vehicle being provided with a combustion engine (1) and an electric traction machine (2) offset on the same line, the hybrid transmission comprising two concentric main shafts (3, 4), a countershaft (5) and a transfer shaft (6), the two concentric main shafts being connected to the combustion engine and the electric traction machine (2) respectively without a disconnecting clutch, the countershaft being connected to the vehicle wheels through a differential (7), the transfer shaft being configured to transmit the movement of the main shaft (3) to the countershaft (5) and to couple these main shafts (3, 4), characterized in that, the hybrid transmission only includes three combustion engine idler gears (8, 9, 10) and at least one main gear (14) fastened to the main shaft (4) connected to the electric traction machine (2), wherein the first two idler gears (8, 9) rotate around the main shaft (3) connected to the combustion engine, and the third idler gear (10) rotates around the transfer shaft (6), the hybrid transmission is connected to an auxiliary motor (16), the output shaft (18) of the auxiliary motor is connected to the transfer shaft (6) through gears so as to be able to accumulate its torque together with the torque of the combustion engine, power is transmitted between the combustion engine (1) and the auxiliary motor (16) in both directions via a triple gear set (18a, 17a, 3a), the triple gear set being located between the main shaft (3) connected to the combustion engine, an intermediate shaft (17) and the output shaft (18) of the auxiliary motor, the intermediate shaft being radially offset from the transfer shaft (6) and from the shaft (18) of the auxiliary motor (16).

2. The hybrid transmission according to claim 1, characterized in that, the third idler gear (10) meshes with a fixed gear (11) of the main shaft (4) connected to the electric traction machine.

3. The hybrid transmission according to claim 1 or 2, characterized in that, the first two idler gears (8, 9) are each capable of establishing a combustion engine transmission ratio (ICE2, ICE4), the combustion engine transmission ratio being mixable by combination with an electric transmission ratio (EV1).

4. The hybrid transmission according to claim 2, characterized in that, the first two idler gears (8, 9) are each capable of establishing a combustion engine transmission ratio (ICE2, ICE4), the combustion engine transmission ratio being mixable by combination with an electric transmission ratio (EV1), the third idler gear (10) is capable of establishing a hybrid mode at two different combustion engine transmission ratios (ICE1 and ICE3).

5. The hybrid transmission according to claim 4, characterized in that, the countershaft (5) carries two idler gears (12, 13), the two idler gears mesh with two fixed gears of the main shaft (4) connected to the electric traction machine, one of the two idler gears is capable of establishing the electric transmission ratio (EV1) and the other is capable of establishing a first combustion engine transmission ratio (ICE1) or a hybrid mode (Hyb3).

6. The hybrid transmission according to claim 5, characterized in that, In this hybrid mode (Hyb3), the torque of the combustion engine (1) is transmitted from the transmission shaft (6) to the countershaft (5) at a second internal combustion transmission ratio (ICE3) via a triple gear set, which includes the third idler gear (10), a fixed gear (11) connected to the main shaft (4) of the electric traction machine (2), and an idler gear (13) of the countershaft (5).

7. The hybrid transmission according to claim 1, characterized in that the hybrid transmission has a series hybrid mode, in which the combustion engine (1) drives the auxiliary motor (16) in generator mode to generate electrical energy, which can be used by the electric traction machine (2) to move the vehicle.

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