CN115891614A

CN115891614A - Hybrid drive system for vehicle

Info

Publication number: CN115891614A
Application number: CN202310078607.0A
Authority: CN
Inventors: 葛海龙; 王健; 徐斌; 周健; 佘晓东; 范玉川; 郑钻玺; 齐方庭
Original assignee: SAIC Motor Corp Ltd
Current assignee: SAIC Motor Corp Ltd
Priority date: 2023-02-08
Filing date: 2023-02-08
Publication date: 2023-04-04

Abstract

A hybrid drive system for a vehicle without any clutch is disclosed, wherein an engine, a TM motor and an ISG motor are rigidly coupled through a gearbox. The gearbox comprises an engine input shaft, a TM motor shaft, an ISG motor shaft, a first intermediate shaft and an output shaft; two transmission gears are realized between the engine input shaft and the first intermediate shaft through two parallel gear pairs, and gear shifting is realized through a single synchronizer; the ISG motor shaft is coupled with the engine input shaft through a gear set; a differential is arranged on the output shaft; the TM motor shaft is coupled with the differential mechanism through a gear set; the first intermediate shaft is coupled to the differential through a gear set. The dynamic property and the fuel economy performance of the whole vehicle can be improved.

Description

Hybrid drive system for vehicle

Technical Field

The present invention relates to a vehicle hybrid drive system.

Background

Among various new energy vehicles, a hybrid vehicle is recognized as one of the most potential new energy vehicles due to good power performance, high fuel efficiency, low exhaust emission and long driving range. Hybrid vehicles have been one of the directions studied by large vehicle enterprises since their advent. Although the technical routes of the families are different, the idea of combining two power sources into one is unfeasible. The existing hybrid power vehicle power assembly has the defects of large occupied space, low matching efficiency of an engine and a motor, poor fuel economy and the like.

Various dual-motor hybrid drive systems exist in which optimal combinations of power and economy may be achieved through combined control of two motors and an engine. However, the existing dual-motor hybrid power driving system still has the disadvantages of high dual-motor cost, complex transmission mechanism structure, difficulty in realizing compact layout and the like.

Therefore, by designing an innovative assembly framework, a hybrid power system with excellent comprehensive performance and cost advantage is developed, and the hybrid power system has important development value.

Disclosure of Invention

For the reasons described above, it is an object of the present invention to provide a dual motor hybrid drive system for a vehicle having better overall performance and lower cost.

According to an aspect of the present invention, there is provided a hybrid drive system for a vehicle, including:

an engine, a TM motor, an ISG motor as a power source; and

a transmission for transmitting the output power of the power source;

the vehicle hybrid power driving system is free of any clutch, and the engine, the TM motor and the ISG motor are rigidly coupled through the gearbox;

the gearbox comprises an engine input shaft, a TM motor shaft, an ISG motor shaft, a first intermediate shaft and an output shaft;

two transmission gears are realized between the engine input shaft and the first intermediate shaft through two parallel gear pairs, and gear shifting is realized through a single synchronizer;

the ISG motor shaft is coupled with the engine input shaft through a gear set;

a differential is arranged on the output shaft;

the TM motor shaft is coupled with the differential through a gear set;

the first intermediate shaft is coupled to the differential through a gear set.

In one embodiment, a first final gear is provided on the first intermediate shaft, and the first final gear meshes with a differential reduction gear as an input of the differential.

In one embodiment, the engine input shaft is provided with a first-gear driving gear and a second-gear driving gear, and the first intermediate shaft is provided with a first-gear driven gear and a second-gear driven gear which are respectively engaged with the first-gear driving gear and the second-gear driving gear; the synchronizer is arranged on the engine input shaft between the first gear driving gear and the second gear driving gear, or arranged on the first intermediate shaft between the first gear driven gear and the second gear driven gear.

In one embodiment, an ISG motor driving gear is disposed on the ISG motor shaft and is engaged with the first gear driving gear or the second gear driving gear, or is engaged with an ISG motor driven gear separately disposed on the engine input shaft, so that the ISG motor shaft is rigidly coupled to the engine input shaft, so that the engine can be speed-regulated by using the ISG motor.

In one embodiment, the TM motor shaft is provided with a TM motor drive gear. The TM motor driving gear is meshed with the first-gear driven gear or the second-gear driven gear; or the TM motor driving gear is meshed with a TM motor driven gear independently arranged on the first intermediate shaft; or the TM motor driving gear is meshed with the differential speed reduction gear.

In one embodiment, the gearbox further comprises a second intermediate shaft, and a TM motor driven gear and a second main reduction gear are arranged on the second intermediate shaft; the TM motor is characterized in that a TM motor driving gear is arranged on a TM motor shaft, the TM motor driving gear is meshed with the TM motor driven gear, and the second main reduction gear is meshed with the differential reduction gear.

In one embodiment, the gearbox further comprises a parking gear wheel, the parking gear wheel being provided on the first intermediate shaft or on the TM motor shaft.

In one embodiment, the engine input shaft is connected to the engine shaft through a damper.

In one embodiment, the power transmission line from the engine to the output shaft comprises the two parallel gear pairs between the engine input shaft and the first countershaft enabling two transmission gears, so that the engine has two gears; the power transmission line from the ISG motor to the output shaft also comprises the two parallel gear pairs between the engine input shaft and the first intermediate shaft for realizing two transmission gears, so that the ISG motor also has two gears; the gears in the gear set between the TM motor shaft and the differential are arranged in series such that the TM motor has a single gear.

In one embodiment, the vehicle hybrid drive system is configured to have the following modes of operation:

the TM pure electric driving mode is characterized in that the TM motor drives the vehicle to drive in the forward direction;

a TM reverse drive mode, in which the vehicle is driven in reverse by the TM motor only;

the pure engine first gear driving mode, wherein the vehicle is driven by the engine in the first gear to drive in the forward direction;

the pure engine two-gear running mode is characterized in that the vehicle is driven to run in the forward direction only by the engine in the two gears;

the ISG motor first gear running mode is characterized in that the ISG motor drives the vehicle to run in the forward direction in the first gear;

the ISG motor is in a two-gear running mode, wherein the ISG motor drives the vehicle to run in the forward direction only in the two gears;

a series mode in which the vehicle is driven to run forward or reverse by only the TM motor while the ISG motor is driven to generate power by the engine so as to charge the vehicle battery;

the braking energy recovery mode is that an output shaft drives a TM motor used as a generator to rotate and generate electricity, and braking energy is recovered;

an idle charging mode, in which the engine drives the ISG motor to generate electricity, and the generated electricity charges the vehicle battery;

a start engine mode in which the SG motor drives the engine from a stopped state to a started state;

a first parallel mode, wherein the vehicle is driven to run forwards by the first gear of the engine and the single gear of the TM motor;

and a second parallel mode, wherein the vehicle is driven by the two gears of the engine and the single gear of the TM motor to run forwards.

In one embodiment, in the first or second parallel mode, the ISG motor is engaged in driving, and power of the ISG motor is combined with power of the engine on the engine input shaft, so that the ISG motor drives the vehicle in the same gear as the engine.

In one embodiment, the vehicle hybrid driving system further comprises a controller that controls operations of the engine, the TM motor, the ISG motor, and the transmission, wherein the controller controls a shift operation in a manner that:

balancing the torque of the engine to 0Nm by the ISG motor;

reversing the synchronizer from one of the two transmission gears to a neutral gear;

the rotation speed of the engine is adjusted by using the ISG motor to be within the gear shifting speed difference range of the synchronizer;

the synchronizer is brought from neutral into the other of said two transmission gears.

According to the basic principle of the present invention, the engine, the TM motor and the ISG motor are used as power sources in the hybrid drive system of the vehicle, and the drive system does not include a clutch, which is completely different from the scheme that the ISG motor needs to be used in combination with one or two clutches, which is generally recognized in the prior art. Compared with the traditional technology of combining an ISG motor and a clutch, the driving system has the advantages that the power switching time is short, and the gear shifting speed is high; rigid connection, no efficiency loss; the clutch and the clutch actuating mechanism are axially omitted, so that the axial length is reduced, the cost is low, and the weight is light.

The invention can regulate the speed of the engine by controlling the ISG motor, and completely solve the problem of power interruption when the automatic gearbox shifts gears by the alternate work of the motor and the engine. When the hybrid parallel driving mode runs, whether the ISG motor participates in driving can be selected according to requirements. The hybrid power driving system has a simple and compact structure, can meet the requirements of pure engines, pure electric and hybrid power running, and can greatly improve the dynamic property and the fuel economy performance of the whole vehicle.

Drawings

Fig. 1 is a layout view of a hybrid drive system of a vehicle according to an embodiment of the invention.

FIG. 2 is a schematic diagram of the engine, TM motor and ISG motor gear combination mode of the driving system.

Fig. 3 is a schematic diagram of power transmission routes in the TM electric only travel mode and the TM reverse travel mode of the drive system.

Fig. 4 and 5 are schematic diagrams of power transmission routes of the drive system in the engine-only two-gear running mode respectively.

Fig. 6 and 7 are schematic diagrams of power transmission routes of an ISG motor of the drive system in a first-gear driving mode.

Fig. 8 and 9 are schematic diagrams of power transmission routes of two gears of the engine and the ISG motor in a parallel mode of the driving system and a gear of the TM motor in combination respectively.

Fig. 10 is a schematic diagram of a power transmission route in the series mode of the drive system.

Fig. 11 is a schematic diagram of a power transmission route in a braking energy recovery mode of the drive system.

Fig. 12 is a schematic diagram of a power transmission route in an idle charge mode of the drive system.

Fig. 13 is a schematic diagram of the power transmission route in the engine start mode of the drive system.

Fig. 14 to 17 are layout views of a hybrid drive system for a vehicle according to some modified embodiments of the present invention.

Detailed Description

The invention belongs to the related technology of vehicle hybrid power assemblies, and relates to a vehicle hybrid power driving system in general which is an original electromechanical coupling configuration of a highly integrated, double-source and two-gear interactive power gear shifting scheme. The driving system comprises an engine, a TM motor and an ISG motor which are used as power sources, and is free of a clutch, effective combination of the motors under two gears and the engine is achieved through switching of a synchronizer, and gear shifting without power interruption is achieved.

In a vehicle hybrid system, if an ISG motor is adopted, the ISG motor is usually connected with the output end of a crankshaft of an engine, and an original flywheel can be eliminated. Depending on the actual situation, one or two clutches are provided between the engine and the gearbox. In the prior art, it is generally considered that if a single clutch is arranged between an ISG motor and a transmission, the ISG motor is mainly used for assisting, generating and starting an engine, and the ISG motor generally cannot drive a vehicle alone; if a single clutch is arranged between the engine and the ISG motor, the ISG motor can be used for driving the vehicle independently, can also assist power and generate electricity, but cannot start the engine; if a double clutch is arranged among the engine, the SG motor and the gearbox, the ISG motor can be used for driving the vehicle independently, starting the engine and parking a vehicle battery for power generation. In summary, in the prior art, it is generally recognized that an ISG motor needs to be used in conjunction with a clutch.

In the vehicle hybrid power driving system of the present invention, an engine, a TM motor, and an ISG motor are used as power sources, but the system does not employ any clutch. Possible embodiments of the present invention are described below with reference to the accompanying drawings.

Fig. 1 shows a hybrid drive system for a vehicle according to an embodiment of the present invention, which mainly includes: an engine 1, a TM motor (main driving motor) 2 and an ISG motor (integrated starting and power generation integrated machine) 3 which are used as power sources; a transmission case 100; a controller 200. The output ends of the engine 1, the TM motor 2 and the ISG motor 3 are connected with the transmission 100, wherein the engine shaft 4 of the engine 1 is connected to the transmission 100 through the damper 5, and the motor shafts of the TM motor 2 and the ISG motor 3 can be directly connected to the transmission 100. The transmission 100 transmits output motions of the engine 1, the TM motor 2, and the ISG motor 3 to vehicle drive wheels. The controller 200 controls the operation of the engine 1, the TM motor 2, the ISG motor 3, and the transmission 100.

The gearbox 100 comprises the following shafts that are position-fittingly connected to the casing of the gearbox 100: the engine comprises an engine input shaft 6, a TM motor shaft 7, an ISG motor shaft 8, a first intermediate shaft 9, a second intermediate shaft 10 and an output shaft 11. The shafts are spatially parallel to each other and at least the body is located within the tank.

The engine input shaft 6 is connected to the engine shaft 4 through a damper 5.

The TM motor shaft 7 may be an external rotating shaft connected to the motor shaft of the TM motor 2, or an integral part of the motor shaft of the TM motor 2. Also, the ISG motor shaft 8 may be an external rotation shaft connected to the motor shaft of the ISG motor 3, or an integral part of the motor shaft of the ISG motor 3.

A differential 12 is provided on the output shaft 11 and is in the form of two differential half shafts leading to two drive wheels of the vehicle.

The engine input shaft 6 is provided with a first gear driving gear 13 and a second gear driving gear 14. The first gear driving gear 13 and the second gear driving gear 14 are fixedly connected to the engine input shaft 6 so as to rotate along with the engine input shaft 6.

The first intermediate shaft 9 is provided with a first-gear driven gear 15 and a second-gear driven gear 16 which are respectively engaged with the first-gear driving gear 13 and the second-gear driving gear 14. The first-gear driven gear 15 and the second-gear driven gear 16 are respectively sleeved on the first intermediate shaft 9 through bearings. The first intermediate shaft 9 is also provided with a parking gear 17 and a first main reduction gear 18. The parking gear 17 and the first final reduction gear 18 are both secured to the first intermediate shaft 9 so as to rotate with the first intermediate shaft 9.

A synchronizer 19 is provided between the first-stage driven gear 15 and the second-stage driven gear 16 on the first countershaft 9. The synchronizer 19 is controlled by the controller 200. The synchronizer 19 is not engaged with any of the first-gear driven gear 15 and the second-gear driven gear 16 in the neutral position (neutral). The synchronizer 19 can be shifted to engage with or disengage from any one of the first-gear driven gear 15 and the second-gear driven gear 16, so that any one of the first-gear driven gear 15 and the second-gear driven gear 16 is fixed to and separated from the first counter shaft 9.

The ISG motor shaft 8 is provided with an ISG motor driving gear 20 which is fixedly connected to the ISG motor shaft 8 so as to rotate along with the ISG motor shaft 8. Also, the ISG motor drive gear 20 meshes with the first gear drive gear 13. According to an alternative, the ISG motor drive gear 20 meshes with the secondary drive gear 14.

The TM motor shaft 7 is provided with a TM motor drive gear 21 which is fixedly attached to the TM motor shaft 7 so as to rotate with the TM motor shaft 7.

The second intermediate shaft 10 is provided with a TM motor driven gear 22 and a second main reduction gear 23. The TM motor driven gear 22 and the second final drive gear 23 are both attached to the second countershaft 10 so as to rotate with the second countershaft 10. The TM motor driven gear 22 is engaged with the TM motor driving gear 21.

A differential reduction gear 24, which is an input of the differential 12, meshes with both the first final reduction gear 18 and the second final reduction gear 23.

By means of the engagement of the first gear driving gear 13 and the second gear driving gear 14 on the engine input shaft 6 with the first gear driven gear 15 and the second gear driven gear 16, respectively, on the first intermediate shaft 9, two different transmission ratios are provided, so that the engine 1 can transmit rotary motion and torque to the output shaft 11 in two gears (and then via the first final reduction gear 18 and the differential reduction gear 24) via these two pairs of gears. At the same time, the ISG motor drive gear 20 on the ISG motor shaft 8 meshes with the first gear drive gear 13 (it is of course also possible to design it to mesh with the second gear drive gear 14), so that the ISG motor 3 can also transmit rotational motion and torque to the output shaft 11 in two gears via these two pairs of gears. Further, the TM motor 2 transmits the rotational motion and the torque to the output shaft 11 in a single gear through a TM motor driving gear 21, a TM motor driven gear 22, a second main reduction gear 23, and a differential reduction gear 24 in this order on the TM motor shaft 7.

The drive system of the invention does not comprise any clutch. The engine 1 is coupled to the gearbox 100 via an engine input shaft 6. The TM motor 2 and the ISG motor 3 are connected into the gearbox 100 through a corresponding TM motor shaft 7 and an ISG motor shaft 8. The ISG motor 3 and the engine 1 are rigidly coupled to the first gear driving gear 13 (or the second gear driving gear 14) through an ISG motor driving gear 20. No clutch is provided between the ISG motor 3 and the engine 1. The power of the ISG motor 3 meets the power of the engine 1 on the engine input shaft 6, and then is transmitted downstream through the two-gear pair.

The engine 1, the TM machine 2, the ISG machine 3 can be used for hybrid parallel drive of a vehicle, possible gear combinations being shown in fig. 2. When the ISG motor 3 is not involved in vehicle driving, the following gear combinations can be realized:

the first gear of the engine 1 is combined with the single gear-first gear of the TM motor 2;

the second gear of the engine 1 is combined with the first gear of the TM motor 2.

When the ISG motor 3 participates in vehicle driving, the following gear combination can be realized:

the first gear of the ISG motor 3 + the first gear of the engine 1 is combined with the first gear of the TM motor 2;

the second gear of the ISG motor 3 + the second gear of the engine 1 is combined with the first gear of the TM motor 2.

The drive system of the invention can generally implement the following modes of operation:

TM pure electric driving;

TM reverse gear driving;

pure engine first gear running;

the pure engine runs at two speeds;

the ISG motor runs in the first gear;

the ISG motor runs in two gears;

a first parallel mode: the engine is in first gear + (the ISG motor is in first gear, and the participation can be selected) + TM single-gear running;

second parallel mode: the engine is in the second gear plus (the ISG motor is in the second gear, and the engine can selectively participate in plus TM single-gear running;

a series mode;

recovering braking energy;

charging at an idle speed;

the engine is started.

These modes are controlled by the controller 200. These operation modes are described in sequence with reference to fig. 3 to 13, in which the power transmission line is indicated by a chain line with an arrow in each figure.

The TM pure electric travel mode is depicted in fig. 3, in which the vehicle is driven to travel only by the TM motor 2. The synchronizer 19 is now in the neutral position (neutral) and is not engaged with either of the first-gear driven gear 15 and the second-gear driven gear 16.

In the TM pure electric running mode, the power of the TM motor 2 is transmitted to the differential 12 through the TM motor shaft 7, the TM motor drive gear 21, the TM motor driven gear 22, the second intermediate shaft 10, the second main reduction gear 23, and the differential reduction gear 24 in this order, and is finally output through the output shaft 11, driving the vehicle to run in the forward direction.

The power transmission line in the TM reverse travel mode is the same as that shown in fig. 3 except that the controller 200 controls the TM motor 2 to rotate in reverse to drive the vehicle in reverse.

The engine-only first gear driving mode is depicted in fig. 4, in which the synchronizer 19 is shifted toward the first gear driven gear 15 to engage with the first gear driven gear 15, so that the first gear driven gear 15 is secured with the first countershaft 9. The power of the engine 1 is transmitted to the differential 12 through the damper 5, the engine input shaft 6, the first gear driving gear 13, the first gear driven gear 15, the first intermediate shaft 9, the first main reduction gear 18 and the differential reduction gear 24 in sequence, and is finally output through the output shaft 11 to drive the vehicle to run in the forward direction.

The engine-only two-gear drive mode is depicted in fig. 5, in which the synchronizer 19 is shifted towards the two-gear driven gear 16 into engagement with the two-gear driven gear 16, so that the two-gear driven gear 16 is secured to the first countershaft 9. The power of the engine 1 is transmitted to the differential 12 through the damper 5, the engine input shaft 6, the second gear driving gear 14, the second gear driven gear 16, the first intermediate shaft 9, the first main reduction gear 18 and the differential reduction gear 24 in sequence, and is finally output through the output shaft 11 to drive the vehicle to run in the forward direction.

A pure ISG motor first gear driving mode is depicted in fig. 6, in which the synchronizer 19 is shifted towards the first gear driven gear 15 to engage with the first gear driven gear 15. The power of the ISG motor 3 is transmitted to the differential 12 through the ISG motor shaft 8, the ISG motor driving gear 20, the first gear driving gear 13, the first gear driven gear 15, the first intermediate shaft 9, the first main reduction gear 18 and the differential reduction gear 24 in sequence, and finally output through the output shaft 11 to drive the vehicle to run in the forward direction.

The pure ISG motor two-gear drive mode is depicted in fig. 7, in which the synchronizer 19 is shifted towards the two-gear driven gear 16 into engagement with the two-gear driven gear 16. The power of the ISG motor 3 is transmitted to the differential 12 through the ISG motor shaft 8, the ISG motor driving gear 20, the first gear driving gear 13, the engine input shaft 6, the second gear driving gear 14, the second gear driven gear 16, the first intermediate shaft 9, the first main reduction gear 18 and the differential reduction gear 24 in sequence, and finally output through the output shaft 11 to drive the vehicle to run in the forward direction.

The first parallel mode is depicted in fig. 8: engine first + TM single drive (ISG motor first is optional). Wherein the synchronizer 19 is shifted toward the first-gear driven gear 15 to engage with the first-gear driven gear 15. The power of the engine 1 is transmitted to the differential reduction gear 24 through the damper 5, the engine input shaft 6, the first-gear drive gear 13, the first-gear driven gear 15, the first intermediate shaft 9, and the first main reduction gear 18 in this order. Meanwhile, the power of the TM motor 2 is transmitted to the differential reduction gear 24 through the TM motor shaft 7, the TM motor driving gear 21, the TM motor driven gear 22, the second intermediate shaft 10, and the second main reduction gear 23 in this order. The power of the engine 1 and the power of the TM motor 2 are transmitted to the differential 12 through the differential reduction gear 24, and finally output through the output shaft 11, thereby driving the vehicle to travel in the forward direction.

In the parallel mode, if the ISG motor 3 is required to be driven, the power of the ISG motor 3 sequentially passes through the ISG motor shaft 8 and the ISG motor driving gear 20 to reach the first gear driving gear 13, the first gear driving gear 13 and the power of the engine 1 converge, and then are transmitted to the differential reduction gear 24 through the first gear driven gear 15, the first intermediate shaft 9 and the first main reduction gear 18, and then converged and transmitted to the differential 12 with the power of the TM motor 2, and finally output through the output shaft 11.

A second parallel mode is depicted in fig. 9: the engine runs in two gears and TM single gear (the ISG motor runs in two gears is an option). Wherein the synchronizer 19 is shifted toward the second-stage driven gear 16 to engage with the second-stage driven gear 16. The power of the engine 1 is transmitted to the differential reduction gear 24 through the damper 5, the engine input shaft 6, the second gear drive gear 14, the second gear driven gear 16, the first intermediate shaft 9, and the first final reduction gear 18 in this order. Meanwhile, the power of the TM motor 2 is transmitted to the differential reduction gear 24 through the TM motor shaft 7, the TM motor driving gear 21, the TM motor driven gear 22, the second intermediate shaft 10, and the second main reduction gear 23 in this order. The power of the engine 1 and the power of the TM motor 2 are transmitted to the differential 12 through the differential reduction gear 24, and finally output through the output shaft 11, thereby driving the vehicle to travel in the forward direction.

In the parallel mode, if the ISG motor 3 is required to be driven, the power of the ISG motor 3 sequentially passes through the ISG motor shaft 8, the ISG motor driving gear 20, the first gear driving gear 13, and the engine input shaft 6 to reach the second gear driving gear 14, then is converged with the power of the engine 1 at the second gear driving gear 14, then is transmitted to the differential reduction gear 24 together through the second gear driven gear 16, the first intermediate shaft 9, and the first main reduction gear 18, then is converged with the power of the TM motor 2 to be transmitted to the differential 12, and finally is output through the output shaft 11.

The series mode is depicted in fig. 10, where the synchronizer 19 is in the middle position. The power of the TM motor 2 is transmitted to the differential 12 through the TM motor shaft 7, the TM motor driving gear 21, the TM motor driven gear 22, the second intermediate shaft 10, the second main reduction gear 23, and the differential reduction gear 24 in order, and is finally output through the output shaft 11 to drive the vehicle to run in the forward direction (or not). On the other hand, the power of the engine 1 is transmitted to the ISG motor 3 through the damper 5, the engine input shaft 6, the first gear driving gear 13, the ISG motor driving gear 20, and the ISG motor shaft 8 in sequence, the ISG motor 3 is driven to rotate by the engine 1 as a generator to generate electricity, the generated electricity charges a vehicle battery (not shown), and the TM motor 2 drives the vehicle to travel in the forward or reverse direction as described above using the electricity of the battery (TM pure electric travel).

Fig. 11 depicts braking energy recovery with synchronizer 19 in the neutral position. When the vehicle decelerates, the output shaft 11 drives the differential 12 to rotate, the rotation is transmitted to the TM motor 2 through the differential reduction gear 24, the second main reduction gear 23, the second intermediate shaft 10, the TM motor driven gear 22, the TM motor driving gear 21 and the TM motor shaft 7 in sequence, the TM motor 2 used as a generator is driven to rotate and generate electricity, and the braking energy is recovered.

Fig. 12 depicts the idle charge mode, wherein the synchronizer 19 is in the neutral position. When the battery is low, the power of the engine 1 is transmitted to the ISG motor 3 through the damper 5, the engine input shaft 6, the first gear driving gear 13, the ISG motor driving gear 20 and the ISG motor shaft 8 in sequence, the ISG motor 3 is used as a generator and driven by the engine 1 to rotate so as to generate electricity, and the generated electricity charges the vehicle battery.

Fig. 13 depicts the start engine mode, wherein the synchronizer 19 is in the neutral position. When the vehicle is started or the vehicle is switched from the pure electric drive working condition to the hybrid drive working condition, the ISG motor 3 can be used as a starter of the engine 1. The power of the ISG motor 3 is transmitted to the engine 1 through the ISG motor shaft 8, the ISG motor drive gear 20, the first gear drive gear 13, the engine input shaft 6, and the damper 5 in this order, and the engine 1 is changed from a stopped state to a started state.

It is understood that, if necessary, the driving system of the present invention may also be connected to the ISG motor 3 (first gear or second gear) as an assist force in the TM electric-only running mode of the TM motor 2.

The following describes the shift operation of the engine 1. As described above, the corresponding gear of the engine 1 is achieved by engagement of the synchronizer 19 with one of the first-gear driven gear 15 and the second-gear driven gear 16. In the engine-only driving mode, if the rotation speed of the engine 1 is not suitable for the current gear and a gear shift is required, the controller 200 may perform an automatic gear shift operation. Firstly, controlling an ISG motor 3 to balance the torque of the engine 1 to 0Nm sequentially through an ISG motor shaft 8, an ISG motor driving gear 20, a first gear driving gear 13, an engine input shaft 6 and a shock absorber 5, and shifting a synchronizer 19 to be separated from a currently engaged first gear driven gear 15 or a second gear driven gear 16 (gear backing); then, the rotation speed of the engine 1 is adjusted by the ISG motor 3 through the power line, and after the rotation speed is adjusted to be within the range of the shift speed difference of the synchronizer 19, the synchronizer 19 is shifted to be engaged with the second-gear driven gear 16 or the first-gear driven gear 15 on the other side (gear shifting), so that the gear shifting of the engine 1 is realized. Such a shift operation of using the ISG motor 3 to speed the engine 1 may also be performed for the hybrid drive mode in which the ISG motor 3 participates. The invention can realize gear selection and shifting by adopting an electric gear shifting mode or a hydraulic gear shifting mode.

In a vehicle hybrid power driving system adopting a clutch, during gear shifting operation, the clutch needs to be disconnected firstly, the synchronizer is withdrawn from neutral, the ISG motor directly enters the gear after the speed of the engine is regulated, and then the clutch is closed to access the power of the engine. The gear shifting operation of the scheme has long power interruption time of the engine.

According to the invention, the ISG motor balances the torque of the engine to 0Nm, the synchronizer is shifted out, the ISG motor directly shifts after speed regulation, the power interruption time of the engine is shorter, and compared with a system adopting a clutch, the gear shifting speed is faster by about 200 ms.

Further, in a hybrid drive system for a vehicle employing a clutch, there is a large loss of efficiency in transmitting torque by slip friction when the clutch is engaged. According to the invention, the driving system is not provided with a clutch, the power sources are rigidly connected, and particularly, the engine 1 and the ISG motor 3 are rigidly coupled through a pair of gears meshed with each other, so that the friction efficiency loss is avoided.

In addition, when the clutch is used, a long axial space is required for arranging the clutch and the clutch actuator, which causes difficulty in layout. According to the invention, a clutch and a clutch actuating mechanism are omitted in the axial direction, and the axial direction can be reduced by about 50mm.

In addition, a set of clutch and clutch actuator is added, and the overall weight and cost of the drive system are increased accordingly. According to the invention, the weight and cost of the clutch and the clutch actuator are eliminated.

It will be appreciated that those skilled in the art, on consideration of the present disclosure, may make various modifications to the technical details described and illustrated herein.

For example, in the embodiment shown in fig. 14, the first-stage driven gear 15 and the second-stage driven gear 16 are fixed to the first countershaft 9. The first gear driving gear 13 and the second gear driving gear 14 are respectively sleeved on the engine input shaft 6 through bearings. Moreover, the synchronizer 19 is modified on the engine input shaft 6, located between the first gear driving gear 13 and the second gear driving gear 14, and is used for engaging with or disengaging from the first gear driving gear 13 and the second gear driving gear 14 to realize a corresponding gear in the two gears. Further, a parking gear 17 is provided on the TM motor shaft 7 instead. The engine input shaft 6 is also fixedly connected with an ISG motor driven gear 25 which is meshed with an ISG motor driving gear 20 on an ISG motor shaft 8. Other aspects of the embodiment shown in fig. 14 are the same as or similar to the embodiment shown in fig. 1 and described with reference to fig. 2-13, and the same foregoing technical effects can be obtained, and will not be described again.

In the embodiment shown in fig. 15, the double countershafts (first countershaft 9, second countershaft 10) are changed to a single countershaft (first countershaft 9). The first gear driving gear 13 and the second gear driving gear 14 are respectively sleeved on the engine input shaft 6 through bearings. The synchronizer 19 is disposed between the first gear driving gear 13 and the second gear driving gear 14 on the engine input shaft 6, and is configured to engage with or disengage from the first gear driving gear 13 and the second gear driving gear 14 to implement a corresponding one of the two gears. The engine input shaft 6 is also fixedly connected with an ISG motor driven gear 25 which is meshed with an ISG motor driving gear 20 on an ISG motor shaft 8.

The first intermediate shaft 9 is fixedly connected with a first-gear driven gear 15 and a second-gear driven gear 16 which are respectively meshed with the first-gear driving gear 13 and the second-gear driving gear 14. A first final reduction gear 18 is also fixedly arranged on the first intermediate shaft 9 and is meshed with a differential reduction gear 24 of the differential 12.

And a parking gear 17 and a TM motor driving gear 21 are fixedly connected to a TM motor shaft 7 of the TM motor 2. The TM motor driving gear 21 meshes with the second-gear driven gear 16 (or meshes with the first-gear driven gear 15, or meshes with a TM motor driven gear (not shown) separately and fixedly connected to the first intermediate shaft 9).

Other aspects of the embodiment shown in fig. 15 are the same as or similar to the embodiment shown in fig. 1 and described with reference to fig. 2-13, and the same foregoing technical effects can be obtained and will not be repeated. In addition, the embodiment of figure 15 reduces one intermediate shaft and the corresponding final reduction gear, resulting in a smaller number of parts and a more compact size.

As a modification (not shown) of the embodiment shown in fig. 15), the first-gear drive gear 13 and the second-gear drive gear 14 may be fixedly attached to the engine input shaft 6, the first-gear driven gear 15 and the second-gear driven gear 16 may be respectively journaled on the first counter shaft 9 through bearings, and the synchronizer 19 may be provided between the first-gear driven gear 15 and the second-gear driven gear 16 on the first counter shaft 9. In this modification, the engine input shaft 6 may retain the ISG motor driven gear 25; alternatively, the ISG motor driven gear 25 may be eliminated from the engine input shaft 6, and the ISG motor drive gear 20 may be engaged with one of the first gear drive gear 13 and the second gear drive gear 14.

In the embodiment shown in fig. 16, the ISG motor driving gear 20 of the ISG motor shaft 8 is engaged with the ISG motor driven gear 25 fixedly disposed on the engine input shaft 6, rather than with one of the first gear driving gear 13 and the second gear driving gear 14, so that the first gear driving gear 13 or the second gear driving gear 14 is prevented from being worn at an excessive speed. Other aspects of the embodiment shown in fig. 16 are the same as or similar to the embodiment shown in fig. 1 and described with reference to fig. 2-13, and the same foregoing technical effects can be obtained and will not be repeated.

In the embodiment shown in fig. 17, the second intermediate shaft 10 and the TM motor driven gear 22 and the second main reduction gear 23 thereon are eliminated relative to the embodiment shown in fig. 1, and the TM motor driving gear 21 on the TM motor shaft 7 of the TM motor 2 directly meshes with the differential reduction gear 24 of the differential 12. Other aspects of the embodiment shown in fig. 17 are the same as or similar to the embodiment shown in fig. 1 and described with reference to fig. 2-13, and the same foregoing technical effects can be obtained, and will not be described again. In addition, the embodiment shown in fig. 17 reduces the number of parts and the size of the second intermediate shaft and the two gears on the second intermediate shaft, and is more compact. It will be appreciated that for the embodiment of fig. 14 and 16, it is likewise possible to eliminate the second intermediate shaft 10 and the TM motor driven gear 22 and the second main reduction gear 23 thereon, with the TM motor drive gear 21 directly meshing with the differential reduction gear 24.

Various features of the embodiments described above may be combined with or substituted for one another without departing from the scope of the invention.

Other modifications can be envisaged by the skilled person as a practical matter.

Although the invention is described herein with reference to specific embodiments, the scope of the invention is not intended to be limited to the details shown. Various modifications may be made to these details without departing from the underlying principles of the invention.

Claims

1. A vehicle hybrid drive system, comprising:

an engine (1), a TM motor (2), and an ISG motor (3) as power sources; and

a transmission (100) for transmitting an output power of the power source;

the vehicle hybrid power driving system is free of any clutch, and the engine (1), the TM motor (2) and the ISG motor (3) are rigidly coupled through the gearbox (100);

the gearbox (100) comprises an engine input shaft (6), a TM motor shaft (7), an ISG motor shaft (8), a first intermediate shaft (9) and an output shaft (11);

two transmission gears are realized between the engine input shaft (6) and the first intermediate shaft (9) through two parallel gear pairs, and the gear shifting is realized through a single synchronizer (19);

the ISG motor shaft (8) is coupled with the engine input shaft (6) through a gear set;

a differential (12) is arranged on the output shaft (11);

the TM motor shaft (7) is coupled with the differential (12) through a gear set;

the first intermediate shaft (9) is coupled to the differential (12) via a gear train.

2. The vehicle hybrid drive system according to claim 1, wherein a first final reduction gear (18) is provided on the first intermediate shaft (9), the first final reduction gear (18) meshing with a differential reduction gear (24) as an input of the differential (12).

3. The vehicle hybrid drive system according to claim 2, wherein a first gear drive gear (13) and a second gear drive gear (14) are provided on the engine input shaft (6), and a first gear driven gear (15) and a second gear driven gear (16) which are respectively engaged with the first gear drive gear (13) and the second gear drive gear (14) are provided on the first countershaft (9);

the synchronizer (19) is arranged on the engine input shaft (6) between the first gear driving gear (13) and the second gear driving gear (14), or arranged on the first intermediate shaft (9) between the first gear driven gear (15) and the second gear driven gear (16).

4. The vehicle hybrid driving system according to claim 3, wherein the ISG motor shaft (8) is provided with an ISG motor driving gear (20) which is engaged with either the first gear driving gear (13) or the second gear driving gear (14) or with an ISG motor driven gear (25) separately provided on the engine input shaft (6), whereby the ISG motor shaft (8) is rigidly coupled with the engine input shaft (6) so that the engine (1) can be speed-regulated by the ISG motor (3).

5. The vehicle hybrid drive system according to claim 3, wherein said TM motor shaft (7) is provided with a TM motor drive gear (21);

the TM motor driving gear (21) is meshed with the first-gear driven gear (15) or the second-gear driven gear (16);

or the TM motor driving gear (21) is meshed with a TM motor driven gear which is arranged on the first intermediate shaft (9) independently;

alternatively, the TM motor drive gear (21) meshes with the differential reduction gear (24).

6. The vehicle hybrid drive system according to any one of claims 2 to 4, wherein the gearbox further comprises a second intermediate shaft (10), the second intermediate shaft (10) being provided with a TM motor driven gear (22) and a second main reduction gear (23);

the TM motor is characterized in that a TM motor driving gear (21) is arranged on the TM motor shaft (7), the TM motor driving gear (21) is meshed with the TM motor driven gear (22), and the second main reduction gear (23) is meshed with the differential reduction gear (24).

7. The vehicle hybrid drive system according to any one of claims 1-4, wherein the gearbox further comprises a parking gear (17), the parking gear (17) being provided on the first countershaft (9) or on the TM motor shaft (7).

8. The vehicle hybrid drive system according to any one of claims 1-4, wherein the engine input shaft (6) is connected to the engine shaft (4) through a damper (5).

9. The vehicle hybrid drive system according to any one of claims 1 to 4, wherein the power transmission line from the engine (1) to the output shaft (11) comprises the two parallel gear pairs between the engine input shaft (6) and the first countershaft (9) that effect two transmission gears, so that the engine (1) has two gears;

the power transmission line from the ISG motor (3) to the output shaft (11) also comprises the two parallel gear pairs between the engine input shaft (6) and the first intermediate shaft (9) for realizing two transmission gears, so that the ISG motor (3) also has two gears;

the gears in the gear set between the TM motor shaft (7) and the differential (12) are arranged in series such that the TM motor (2) has a single gear.

10. The vehicle hybrid drive system of claim 9, wherein the vehicle hybrid drive system is configured to have the following modes of operation:

a TM pure electric driving mode, wherein the TM motor (2) drives the vehicle to drive in the forward direction;

a TM reverse gear driving mode, wherein the vehicle is driven by the TM motor (2) to drive in a reverse direction;

the pure engine first gear running mode is characterized in that the vehicle is driven to run in the forward direction by the engine (1) in the first gear;

the pure engine two-gear running mode is characterized in that the vehicle is driven by the engine (1) in two gears to run in the forward direction;

the ISG motor first gear running mode is characterized in that the vehicle is driven to run in the forward direction only by the ISG motor (3) in the first gear;

the ISG motor is in a two-gear running mode, wherein the ISG motor (3) drives the vehicle to run in the forward direction in the two gears;

a series mode in which the vehicle is driven to run forward or backward only by the TM motor (2) while the ISG motor (3) is driven by the engine (1) to generate electricity to charge the vehicle battery;

the braking energy recovery mode is characterized in that the output shaft (11) drives the TM motor (2) used as a generator to rotate and generate electricity, and the braking energy is recovered;

an idle charging mode, wherein the engine (1) drives the ISG motor (3) to generate electricity, and the generated electricity charges a vehicle battery;

a start engine mode in which the SG motor (3) drives the engine (1) to change the engine (1) from a stopped state to a started state;

a first parallel mode, wherein the vehicle is driven to run in the forward direction by the first gear of the engine (1) and the single gear of the TM motor (2);

and in the second parallel mode, the two gears of the engine (1) and the single gear of the TM motor (2) drive the vehicle to run in the forward direction.

11. The vehicle hybrid drive system according to claim 10, wherein in the first or second parallel mode, the ISG motor (3) participates in driving, and the power of the ISG motor (3) meets the power of the engine (1) on the engine input shaft (6) so that the ISG motor (3) drives the vehicle in the same gear as the engine (1).

12. The vehicle hybrid drive system according to any one of claims 1-4, further comprising a controller (200) that controls the operation of the engine (1), the TM motor (2), the ISG motor (3), the transmission (100), wherein the controller (200) controls a shift operation in the following manner:

balancing the torque of the engine (1) to 0Nm with the ISG motor (3);

reversing the synchronizer (19) from one of the two transmission gears to a neutral gear;

the rotation speed of the engine (1) is adjusted by using the ISG motor (3) to be within the range of the gear shifting speed difference of the synchronizer (19);

the synchronizer (19) is brought from neutral into the other of the two transmission gears.