Hybrid transmissions, systems, and vehicles

Abstract

The present application belongs to the field of automobile power transmission technology, and particularly relates to a hybrid power transmission, a system and a vehicle. The hybrid power transmission comprises a two-gear transmission mechanism, an input shaft, a first output shaft, a second output shaft, a first gear pair and a second gear pair, the input shaft is in transmission connection with the first output shaft and the second output shaft through the first gear pair or the second gear pair, a P1 motor has a P1 motor shaft, the P1 motor shaft is in transmission connection with the input shaft through an idler shaft, a P3 motor has a P3 motor shaft, and the P3 motor shaft is in transmission connection with the first output shaft and the second output shaft. The present application is arranged through the functional separation of the P1 motor and the P3 motor, and is integrated with the two-gear transmission mechanism and an electronic cog differential lock, so that the front axle driving force can still be maintained in the power feeding state, and the gear switching is adapted to different vehicle speed working condition requirements in the engine direct drive mode, without relying on a complex energy management control strategy to adapt to the full scene operation requirements of hard off-road.

Description

Technical Field

[0001] This invention belongs to the field of automotive powertrain technology, and particularly relates to hybrid transmissions, systems and vehicles. Background Technology

[0002] In a single-motor hybrid transmission solution, only one motor is integrated into the transmission, which must simultaneously perform both power generation and driving functions. When the power battery is depleted, the motor must switch to power generation mode to replenish the battery. As a result, the front axle loses its motor driving force and cannot coordinate with the rear axle drive system, making it impossible to achieve all-scenario four-wheel drive mode when the battery is depleted.

[0003] In the dual-motor single-speed hybrid transmission solution, the two motors respectively handle power generation and driving functions, which alleviates the four-wheel drive problem to some extent when the battery is depleted. However, in this solution, the transmission ratio is fixed and cannot be adjusted when the engine is in direct drive. Under low-speed off-road conditions, the fixed transmission ratio cannot provide sufficient output torque to meet the off-road requirements; under high-speed cruising conditions, the same transmission ratio causes the engine operating point to deviate from the economic range, resulting in higher fuel consumption. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides a hybrid transmission, system and vehicle. By functionally separating the P1 motor and P3 motor and integrating a two-speed transmission mechanism with an electronic dog clutch differential lock, the front axle driving force can still be maintained in the power depletion state. At the same time, in the engine direct drive mode, the gear switching can adapt to different vehicle speed conditions. It can adapt to the all-scenario operation requirements of hardcore off-road vehicles without relying on complex energy management control strategies.

[0005] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions: The first aspect of the present invention provides a hybrid power transmission.

[0006] Hybrid transmissions, including: A two-speed transmission mechanism, comprising an input shaft, a first output shaft, a second output shaft, a first gear pair, and a second gear pair, wherein the input shaft is connected to the first output shaft and the second output shaft via the first gear pair or the second gear pair; P1 motor, the P1 motor having a P1 motor shaft, the P1 motor shaft being connected to the input shaft via an idler wheel shaft, the P1 motor being used to convert mechanical energy into electrical energy for power generation; The P3 motor has a P3 motor shaft, which is connected to a first output shaft and a second output shaft. The P3 motor is used to convert electrical energy into mechanical energy to drive the vehicle.

[0007] As an optional technical solution, dual electric control is also included, which is used to independently control the P1 motor and the P3 motor; The dual electric control system includes P1 electric control and P3 electric control. P1 electric control is electrically connected to P1 motor, and P3 electric control is electrically connected to P3 motor.

[0008] As an alternative technical solution, the dual electronic control is electrically connected to the power battery. The electrical energy generated by the P1 motor is stored in the power battery via the P1 electronic control, and the electrical energy stored in the power battery is output to the P3 motor via the P3 electronic control.

[0009] As an alternative technical solution, a shifting system is also included, wherein the transmission ratio of the second gear pair is less than the transmission ratio of the first gear pair.

[0010] As an alternative technical solution, a differential is also included, wherein the differential is connected to the first output shaft and the second output shaft, and the two output ends of the differential are respectively connected to the left drive shaft and the right drive shaft.

[0011] As an alternative technical solution, an electronic dog clutch differential lock is also included. The electronic dog clutch differential lock is connected to the differential and is used to lock the differential so that the output speeds on both sides of the differential are kept consistent.

[0012] As an optional technical solution, a shifting system is also included, which is connected to a two-speed transmission mechanism and is used to switch the transmission state between the first gear pair and the second gear pair and realize the switching between N gear, first gear and second gear. The shifting system includes a shift motor, a shift hub, and a shift fork. The shift motor drives the shift hub to rotate, and the shift hub drives the shift fork to shift the two-speed transmission mechanism between N gear, first gear, and second gear.

[0013] As an alternative technical solution, an electronic oil pump is also included, which is connected to the mechanical transmission part of the two-speed transmission mechanism and is used to actively lubricate the two-speed transmission mechanism. The electronic oil pump integrates a drive motor and a controller. The controller controls the drive motor to drive the electronic oil pump through independent software, so as to provide lubricating oil to the mechanical transmission part of the two-speed transmission mechanism.

[0014] A second aspect of the present invention provides a hybrid power transmission system.

[0015] A hybrid power transmission system, comprising: An engine and a dual-mass flywheel, wherein the dual-mass flywheel is connected to the output end of the engine; As described in the first aspect, the input shaft of the hybrid transmission is connected to the dual-mass flywheel drive; The power battery is electrically connected to the P1 motor and P3 motor in the hybrid transmission. And a drive shaft, which is connected to the output of the differential in the hybrid transmission for transmitting power to the wheels.

[0016] A third aspect of the present invention provides a vehicle.

[0017] A vehicle including a hybrid transmission system as described in the second aspect.

[0018] The above one or more technical solutions have the following beneficial effects: This invention provides a hybrid transmission, system, and vehicle. Through the division of labor between the P1 and P3 motors, with the P1 motor dedicated to power generation and the P3 motor dedicated to driving, their functions do not interfere with each other. This allows the P1 motor to generate electricity while the P3 motor continues to drive the front axle even when the battery is depleted, enabling all-scenario four-wheel drive in conjunction with the rear axle drive system. This fundamentally solves the structural defect of front axle loss of driving force when a single-motor hybrid transmission is depleted. The two-speed transmission mechanism switches between a high-ratio first gear pair and a low-ratio second gear pair. In engine direct drive mode, the high ratio is engaged at low speeds to obtain greater output torque, improving off-road capability. At high speeds, the low ratio is engaged to keep the engine operating in its economical speed range, improving fuel economy, thus achieving a harmonious balance between low-speed high torque and high-speed fuel efficiency. An integrated electronic locking differential further locks the differential, ensuring consistent wheel speeds and significantly improving vehicle passability under extreme off-road conditions.

[0019] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0021] Figure 1 This is a schematic diagram of the vehicle architecture in one or more embodiments of the present invention that utilizes the hybrid transmission system; Figure 2 This is a schematic diagram of the overall structure of the hybrid power transmission in one or more embodiments of the present invention; Figure 3 This is a schematic diagram of the power flow direction of the P3 motor driven in pure electric drive mode in one or more embodiments of the present invention; Figure 4This is a schematic diagram of the power flow direction in the series drive mode in one or more embodiments of the present invention; Figure 5 This is a schematic diagram of the power flow direction in the engine direct drive mode in one or more embodiments of the present invention; Figure 6 This is a schematic diagram of the power flow direction when the engine and P3 motor are driven simultaneously in parallel drive mode in one or more embodiments of the present invention. Figure 7 This is a schematic diagram of the power flow in one or more embodiments of the present invention under the engine direct drive and P1 charging mode.

[0022] Explanation of reference numerals in the attached figures: 10—Engine; 20—Dual-mass flywheel; 30—Power battery; 40—P1 generator; 41—P1 motor shaft; 42—Idler shaft; 43—Input shaft; 44—Second gear pair; 45—First gear pair; 50—P3 drive motor; 51—P3 motor shaft; 52—First output shaft; 53—Second output shaft; 60—Differential; 70—Wheel. Detailed Implementation

[0023] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0024] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0025] The powertrain systems of hybrid off-road vehicles have long faced two irreconcilable core contradictions: Firstly, how to maintain all-scenario four-wheel drive capability when the power battery is depleted; Secondly, how to simultaneously satisfy low-speed off-road capability and high-speed fuel economy in engine direct drive mode.

[0026] Regarding the first contradiction, the root cause of existing single-motor hybrid solutions lies in the mutual exclusivity of motor functions—a single motor cannot simultaneously output driving torque while generating electricity, causing the front axle to inevitably lose driving force when the power is cut off. This contradiction cannot be overcome at the physical level through optimization of control strategies; it can only be fundamentally solved by increasing the number of motors and achieving functional separation.

[0027] Regarding the second contradiction, the root cause of the existing dual-motor single-speed solution lies in the fixed transmission ratio—a single gear cannot simultaneously adapt to the two drastically different operating conditions of low-speed high torque and high-speed low torque. The engine's operating point deviates from the maximum torque range at low speeds and from the economic range at high speeds, and performance loss is unavoidable under both conditions. Only by introducing a multi-speed transmission mechanism can the engine operate within a suitable speed range at different vehicle speeds by switching the transmission ratio.

[0028] In addition, hardcore off-road vehicles also face the problem of severely uneven traction between the left and right wheels in extreme terrains such as deserts, mud, and rocks. In such conditions, the differential function of the differential becomes a negative factor that hinders passage. A differential lock is needed to force the left and right wheels to maintain the same speed and ensure that power is effectively transmitted to the wheel with better traction.

[0029] Based on the above analysis, this invention proposes a longitudinally mounted two-speed dual-motor hybrid power transmission assembly. By dividing the work of the two motors into a dedicated power generation P1 motor and a dedicated drive P3 motor, and combining the integrated design of a first / second gear transmission mechanism and an electronic dog clutch differential lock, the three core technical problems mentioned above are systematically solved.

[0030] Example 1 This embodiment provides a hybrid transmission adapted to the front axle drive system of rugged off-road vehicles. It is equipped with an engine, power battery, and rear axle drive system, achieving a comprehensive goal of all-scenario four-wheel drive, low-speed high-torque off-road capability, and high-speed fuel economy. Its core improvement objective is to maintain front axle drive force even when the battery is depleted by functionally separating the P1 and P3 motors, combined with a two-speed transmission mechanism and an electronic locking differential. Simultaneously, in engine direct drive mode, it adapts to different vehicle speed conditions through gear shifting, meeting the all-scenario operational needs of rugged off-road vehicles without relying on complex energy management control strategies.

[0031] The hybrid transmission in this embodiment follows the design principle of "functional separation and structural integration" in its overall concept. Functional separation means that the power generation function and the drive function are independently undertaken by the P1 motor and the P3 motor, respectively. Electrically, they are connected to the power battery through dual electronic controls, and mechanically, they are connected to the transmission mechanism through their respective transmission paths. The two sets of functional paths are physically independent and do not interfere with each other.

[0032] The term "structural integration" refers to integrating the two-speed transmission mechanism, shifting system, electronic dog-clutch differential lock, TCU, and electronic oil pump all into a single transmission housing, forming a highly integrated hybrid-specific transmission assembly that maximizes functional density within a limited engine compartment space. This overall concept fundamentally determines the technological advantages of this invention in three dimensions: electric-powered four-wheel drive, gear shifting, and off-road locking.

[0033] The hybrid power transmission provided in this embodiment includes: P1 motor, the P1 motor having a P1 motor shaft, the P1 motor shaft being connected to the input shaft via an idler wheel shaft, the P1 motor being used to convert mechanical energy into electrical energy for power generation; The P3 motor has a P3 motor shaft, which is connected to a first output shaft and a second output shaft. The P3 motor is used to convert electrical energy into mechanical energy to drive the vehicle. A two-speed transmission mechanism includes an input shaft, a first output shaft, a second output shaft, an intermediate shaft, a first gear pair, and a second gear pair. The input shaft is connected to the first output shaft and the second output shaft via the first gear pair or the second gear pair. The shifting system is connected to the two-speed transmission mechanism and is used to switch the transmission state between the first gear pair and the second gear pair and realize the switching between N gear, first gear and second gear; An electronic jaw differential lock, connected to the differential, is used to lock the differential so that the output speeds on both sides of the differential are kept consistent. The TCU is connected to the shift system via a signal and is used to control the shift system to perform shifting actions. An electronic oil pump is also included, which is connected to the mechanical transmission part of the two-speed transmission mechanism to actively lubricate the two-speed transmission mechanism.

[0034] In some embodiments, the shifting system includes a shift motor, a shift hub, and a shift fork. The shift motor drives the shift hub to rotate, and the shift hub drives the shift fork to shift the two-speed transmission mechanism between N gear, first gear, and second gear.

[0035] In some embodiments, the electronic oil pump integrates a drive motor and a controller. The controller controls the drive motor to drive the electronic oil pump through independent software to provide lubricating oil to the mechanical transmission part of the two-speed transmission mechanism.

[0036] In some embodiments, the hybrid transmission further includes dual electronic control units, which are electrically connected to the P1 motor and the P3 motor respectively, for independently controlling the P1 motor and the P3 motor; the dual electronic control units are electrically connected to the power battery, and the electrical energy generated by the P1 motor is stored in the power battery via the dual electronic control units, and the electrical energy stored in the power battery is output to the P3 motor via the dual electronic control units.

[0037] In some embodiments, the transmission ratio of the second gear pair is less than that of the first gear pair. Under low-speed conditions, the input shaft is connected to the first output shaft and the second output shaft via the first gear pair. Under high-speed conditions, the input shaft is connected to the first output shaft and the second output shaft via the second gear pair.

[0038] In some embodiments, the hybrid transmission has a pure electric drive mode, a series drive mode, an engine direct drive mode, a parallel drive mode, and an engine direct drive combined with electric supplementation mode. The power flow direction is switched by the TCU coordinating the shift system, the working state of the P1 motor and the P3 motor.

[0039] In simple terms, this invention relates to a longitudinally mounted two-speed dual-motor hybrid power transmission assembly, providing an arrangement scheme with advantages in economy, passability, and space utilization. From the perspective of the entire vehicle, the system applied in this invention mainly includes an engine 10, a generator 40, a drive motor 50, a battery 30, and a two-speed transmission mechanism, wherein the transmission mechanism mainly includes an input shaft 43 and a first output shaft 52 and a second output shaft 53.

[0040] The various working modes are briefly summarized below: (1) such as Figure 3 The diagram shows the working principle in pure electric drive mode. The power battery 30 outputs electrical energy to the P3 drive motor 50. The P3 motor converts the electrical energy into mechanical energy and then transmits it through the P3 motor shaft 51 to the first output shaft 52 to the second output shaft 53. Finally, it transmits the energy to the differential assembly 60 and outputs it to the wheel ends to enable the vehicle to move.

[0041] (2) such as Figure 4 The diagram shown illustrates the working principle in series mode. In this mode, the engine 10 transmits mechanical energy to the input shaft 43 via the dual-mass flywheel 20, and then to the P1 motor shaft 41 via the idler shaft 42. This drives the P1 motor 40 to generate electricity, which is stored in the power battery 30. The power battery 30 then outputs electrical energy to the P3 drive motor 50. The P3 motor converts this energy into mechanical energy, which is then transmitted through the P3 motor shaft 51 to the second output shaft 53 via the first output shaft 52. Finally, the energy is transmitted to the differential assembly 60 and output to the wheel ends to enable vehicle movement.

[0042] (3) such as Figure 5The diagram shows the working principle of the engine in direct drive mode. The engine 10 transmits mechanical energy to the input shaft 43 through the dual-mass flywheel 20. At low speeds, the mechanical energy is transmitted to the first output shaft 52 and the second output shaft 53 through the first gear pair, and then to the differential assembly 60, which outputs the energy to the wheels to enable vehicle movement. At high speeds, the mechanical energy is transmitted to the first output shaft 52 and the second output shaft 53 through the second gear pair, and then to the differential assembly 60, which outputs the energy to the wheels to enable vehicle movement.

[0043] (4) such as Figure 6 The diagram shows the working principle in parallel mode. The engine 10 transmits mechanical energy to the input shaft 43 through the dual-mass flywheel 20, and then transmits the mechanical energy to the first output shaft 52 and the second output shaft 53 through a two-speed gear pair, and then to the differential assembly 60. At the same time, the power battery 30 also outputs electrical energy to the P3 drive motor 50. After the P3 motor converts the energy into mechanical energy, it transmits the energy through the P3 motor shaft 51 to the second output shaft 53 via the first output shaft 52, and then to the differential assembly 60. The two power sources drive the wheels simultaneously to drive the vehicle.

[0044] (5) such as Figure 7 The diagram shows the working principle of the engine directly drawing mechanical energy and converting some mechanical energy into electrical energy stored in the power battery. The engine 10 transmits mechanical energy to the input shaft 43 through the dual-mass flywheel 20. At low speeds, the mechanical energy is transmitted to the first output shaft 52 and the second output shaft 53 through the first gear pair, and then to the differential assembly 60, which outputs the energy to the wheels to enable vehicle movement. At high speeds, the mechanical energy is transmitted to the first output shaft 52 and the second output shaft 53 through the second gear pair, and then to the differential assembly 60, which outputs the energy to the wheels to enable vehicle movement. At the same time, some mechanical energy is transmitted to the P1 motor shaft 41 through the idler shaft 42, which drives the P1 motor 40 to generate electricity and store it in the power battery 30.

[0045] Regarding the practical implementation of the specific structure: P1 motor 40 is located on the engine side of the gearbox. Its rotor shaft, namely P1 motor shaft 41, extends along the longitudinal axis of the gearbox. The output end of P1 motor shaft 41 meshes with the gear on idler shaft 42. Idler shaft 42 then meshes with the corresponding gear on input shaft 43, thus forming a transmission path of "P1 motor shaft 41 → idler shaft 42 → input shaft 43".

[0046] The core function of the idler shaft 42 here is to adjust the transmission ratio and coordinate the rotation direction, so that the speed of the P1 motor 40 and the speed of the input shaft 43 can form a reasonable matching relationship, while ensuring that the P1 motor 40 can generate electricity efficiently at an appropriate speed when driven by the engine 10.

[0047] When P1 motor 40 is working normally, it is in the generator state. The motor 10 drives its rotor to rotate through the input shaft 43 and the idler shaft 42, converting mechanical energy into electrical energy and storing it in the power battery 30. Under special working conditions, P1 motor 40 can also switch to electric state briefly to assist the engine 10 in starting or to provide short-term torque supplement.

[0048] P3 motor 50 is located on the output side of the gearbox, and its rotor shaft, namely P3 motor shaft 51, extends along the longitudinal axis of the gearbox. The output end of P3 motor shaft 51 is connected to the first output shaft 52 and the second output shaft 53.

[0049] The first output shaft 52 and the second output shaft 53 together transmit the driving torque of the P3 motor 50 to the differential 60, which then distributes the power to the left and right drive shafts, and finally outputs it to the wheels 70.

[0050] The P3 motor 50 is one of the main drive sources of this transmission. It directly drives the vehicle in pure electric drive mode and parallel drive mode. Its position and direct transmission connection with the output shaft system ensure efficient transmission of drive torque and reduce efficiency loss caused by intermediate transmission links.

[0051] The two-speed transmission mechanism is the core transmission structure of this invention. It consists of three sets of gear shafts: an input shaft 43, an intermediate shaft, a first output shaft 52, and a second output shaft 53. It includes two sets of transmission gear pairs: a first-speed gear pair 45 and a second-speed gear pair 44.

[0052] The second gear pair 44 has a relatively small transmission ratio, which is suitable for high-speed cruising conditions. When the engine 10 is driven by the second gear pair 44, the output shaft speed is high and the torque is moderate. The engine operating speed is in the economic range and the fuel consumption rate is low.

[0053] The first gear pair 45 has a relatively large transmission ratio, which is suitable for low-speed off-road conditions. When the engine 10 is driven by the first gear pair 45, the output shaft speed is low but the torque is greatly amplified, which can provide sufficient low-speed driving force to overcome the driving resistance caused by complex terrains such as deserts and mud, and significantly improve the vehicle's off-road passability.

[0054] The two gear pairs are switched by the shifting system under the control of the TCU to realize the two-speed transmission function in the engine direct drive mode.

[0055] The shifting system consists of three core components: the shift motor, the shift hub, and the shift fork. The shift motor is mounted on the outside of the gearbox housing, and its output shaft is connected to the shift hub. The shift hub is a cylindrical component with a specific cam profile, and its outer circumference is provided with guide grooves. One end of the shift fork is embedded in the guide groove, and the other end engages with the synchronizer or engagement sleeve in the transmission mechanism.

[0056] When the TCU issues a shift command, the shift motor drives the shift hub to rotate at a preset angle. The cam profile of the shift hub guides the shift fork to move axially. The shift fork pushes the synchronizer or engagement sleeve to slide on the input shaft 43, thereby completing the switching between the first gear pair 45 and the second gear pair 44, as well as the engagement process from neutral (N) to first or second gear.

[0057] This shifting method, in which the shifting motor drives the shifting drum, which in turn drives the shifting fork, has advantages over traditional hydraulic shifting, including faster response, higher control precision, and lower energy consumption. It is especially suitable for use in off-road conditions where frequent shifting is required.

[0058] As the control core of the shifting system, the TCU collects vehicle information such as vehicle speed signal, engine speed signal, and accelerator pedal opening signal. Based on the preset shifting strategy, it determines the optimal shifting time and sends precise angle control commands to the shifting motor to ensure a smooth and rapid shifting process.

[0059] The electronic dog-clutch differential lock and differential 60 are integrated within the transmission housing. Its core working principle involves electronically locking the two half-shaft gears of the differential 60 into a synchronized rotation state, thus disabling the differential function and ensuring that the left and right drive shafts rotate at the same speed. Under normal driving conditions, the electronic dog-clutch differential lock is unlocked, and the differential 60 operates normally, allowing the left and right wheels to rotate at different speeds to meet the kinematic requirements of vehicle cornering. Under off-road conditions, when the driver activates the differential lock via a control switch, the electronic control unit drives the dog-clutch mechanism to engage, forcibly locking the output ends of both sides of the differential 60. At this time, the left and right wheels rotate at the same speed, ensuring that even if one wheel is suspended in the air or stuck on a low-traction surface, power can still be effectively transmitted to the other wheel with traction, ensuring the vehicle can successfully extricate itself from difficult situations.

[0060] Compared to friction plate differential locks, the toothed clutch structure has the advantages of large locking torque, reliable locking, and simple structure, making it suitable for high-intensity use scenarios in hardcore off-road vehicles.

[0061] The electronic oil pump is integrated into the gearbox housing and consists of a small drive motor, the pump body, and a dedicated controller. The controller precisely controls the drive motor through an independent software program. The drive motor drives the pump body to rotate, drawing lubricating oil from the oil pan and distributing it through oil passages to the lubrication points of each transmission component of the gearbox, thereby achieving active lubrication of the gear pairs and bearings on the input shaft 43, intermediate shaft, first output shaft 52, and second output shaft 53.

[0062] Compared to traditional passive lubrication methods that rely on gear splash lubrication, the electronic oil pump active lubrication solution can ensure sufficient lubrication supply even when the transmission is operating at low speeds and gear splash lubrication is insufficient. This effectively reduces wear on transmission components and extends the transmission's service life, which is especially important for ensuring transmission reliability under frequent low-speed off-road conditions. The electronic oil pump controller operates through independent software and communicates with the TCU and vehicle control system. It can dynamically adjust the lubricating oil supply based on the transmission's operating status, such as temperature, speed, and operating mode, reducing the electronic oil pump's energy consumption while ensuring adequate lubrication.

[0063] The dual-controller system serves as the core of electrical control for P1 motor 40 and P3 motor 50. It includes two independent controllers corresponding to P1 motor 40 and P3 motor 50 respectively. The two controllers are integrated into the same controller housing to save space, but they are independent of each other in terms of electrical and software aspects and do not interfere with each other.

[0064] The dual-controller is connected to the high-voltage bus of the power battery 30. When the P1 motor 40 generates electricity, the P1 controller in the dual-controller rectifies the AC power output of the P1 motor 40 into DC power and stores it in the power battery 30. When the P3 motor 50 is driven, the P3 controller in the dual-controller inverts the DC power output of the power battery 30 into AC power and drives the P3 motor 50 to rotate.

[0065] The two controllers can work independently at the same time. That is, while P1 motor 40 is generating electricity, P3 motor 50 is driving it, and the two do not affect each other. This is the electrical basis for the invention to achieve all-scenario four-wheel drive in the power-off state.

[0066] The following is a detailed description of the five operating modes of the hybrid transmission in this embodiment: The pure electric drive mode is suitable for urban driving conditions with a fully charged battery (30% charge) and low vehicle speeds, or for low-speed off-road crawling conditions. In this mode, engine 10 stops, the shift system places the two-speed transmission mechanism in neutral (N), disconnecting the transmission path between engine 10 and the transmission mechanism, and P1 motor 40 idles or stops. The power battery 30 outputs electrical energy to P3 motor 50, which converts this energy into mechanical energy. This mechanical energy is then transmitted via P3 motor shaft 51, first output shaft 52, and second output shaft 53. From there, the power is transmitted to differential 60, which distributes the power to the left and right drive shafts, ultimately driving the wheels 70 to rotate and enabling vehicle movement. In pure electric drive mode, the entire power transmission process is engine-free, resulting in zero emissions and low noise, making it suitable for low-speed urban driving scenarios. In off-road low-speed crawling conditions, the characteristics of P3 motor 50 allow it to output near-peak torque at low speeds, providing strong low-speed driving force. Combined with the rear axle drive system, this enables four-wheel drive crawling with excellent off-road capability.

[0067] The series drive mode is suitable for situations where the power battery is low on charge and needs to be replenished to drive the vehicle. In this mode, engine 10 starts and transmits mechanical energy to input shaft 43 via dual-mass flywheel 20. The power on input shaft 43 is transmitted to P1 motor shaft 41 via idler shaft 42, driving the rotor of P1 motor 40 to rotate. P1 motor 40 converts mechanical energy into electrical energy, which is stored in power battery 30 via dual electronic control or directly supplied to P3 motor 50. Simultaneously, power battery 30 outputs electrical energy to P3 motor 50. P3 motor 50 converts electrical energy into mechanical energy, which is then transmitted via P3 motor shaft 51 through first output shaft 52 to second output shaft 53, and finally to differential 60 to drive wheels 70. In series drive mode, all mechanical energy of engine 10 is used to drive P1 motor 40 to generate electricity. There is no mechanical connection between engine 10 and wheels 70. Engine 10 can operate within its optimal efficiency speed range, unconstrained by vehicle speed, which improves fuel economy. In this mode, the shift system places the transmission mechanism in N gear, cutting off the transmission path from engine 10 to the output shaft via the transmission mechanism, ensuring that all the power of engine 10 is converted into electrical energy through P1 motor 40.

[0068] Engine direct drive mode is suitable for high-efficiency transmission scenarios that require the engine to directly drive the vehicle, including medium-high-speed driving and specific off-road conditions: In this mode, the P3 motor 50 is not working or is idling. The engine 10 transmits mechanical energy to the input shaft 43 through the dual-mass flywheel 20. The TCU determines the optimal gear based on the current vehicle speed and controls the shift system to perform the corresponding shift action. In low-speed off-road conditions, the TCU controls the shift system to switch the transmission mechanism to first gear. The power on the input shaft 43 is transmitted to the first output shaft 52 and the second output shaft 53 via the first gear pair 45. The large gear ratio of the first gear pair 45 reduces the output speed of the engine 10 and amplifies the torque, allowing the wheels 70 to obtain greater driving torque, meeting the needs of low-speed off-road passability. In highway driving conditions, the TCU controls the shift system to switch the transmission mechanism to second gear. The power on the input shaft 43 is transmitted to the first output shaft 52 and the second output shaft 53 via the second gear pair 44. The small gear ratio of the second gear pair 44 allows the engine 10 to drive the vehicle at a higher speed at a lower speed. The engine 10's operating point falls into the economic speed range, and the fuel consumption rate is significantly reduced. The two-speed transmission mechanism, through precise gear shifting controlled by the TCU, optimizes the operating point of the engine 10 under different vehicle speed conditions, effectively balancing low-speed passability and high-speed economy.

[0069] Parallel drive mode is suitable for scenarios requiring maximum driving force output, such as high-speed overtaking, heavy-load hill climbing, or off-road hill climbing. In this mode, the engine 10 and the P3 motor 50 simultaneously output driving force, and the two power sources converge in the output shaft system to jointly drive the wheels 70. Specifically, the engine 10 transmits mechanical energy to the input shaft 43 through the dual-mass flywheel 20. The TCU-controlled shift system switches the transmission to first gear, and the power on the input shaft 43 is transmitted to the first output shaft 52 and the second output shaft 53 via the first gear pair 45. At the same time, the power battery 30 outputs electrical energy to the P3 motor 50, which converts the electrical energy into mechanical energy, which is transmitted from the P3 motor shaft 51 to the second output shaft 53 via the first output shaft 52. The mechanical torque transmitted from the engine 10 via the first gear pair 45 and the mechanical torque transmitted from the P3 motor 50 via the P3 motor shaft 51 are superimposed and combined on the first output shaft 52 and the second output shaft 53 to form a combined output torque that far exceeds that of a single power source. This torque is transmitted to the wheels 70 via the differential 60, providing the vehicle with strong driving force. The parallel drive mode fully leverages the peak performance advantages of the hybrid system and is the performance guarantee mode for this transmission under extreme operating conditions.

[0070] The engine direct drive and charging mode is suitable for scenarios where the power battery has a low charge level (30%) and needs to be charged while driving. In this mode, the engine 10 transmits mechanical energy to the input shaft 43 via the dual-mass flywheel 20. The power on the input shaft 43 is transmitted to the first output shaft 52 and the second output shaft 53 via the first gear pair 45 or the second gear pair 44 to drive the vehicle. On the other hand, it is transmitted to the P1 motor shaft 41 via the idler shaft 42 to drive the P1 motor 40 to generate electricity, converting part of the mechanical energy into electrical energy and storing it in the power battery 30.

[0071] In this mode, the power from engine 10 is split, with one part used to drive the vehicle and the other part used to generate electricity for recharging. The distribution ratio between the two is dynamically adjusted by the vehicle control system based on parameters such as current vehicle speed, throttle opening, and battery charge to achieve an optimal balance between driving performance and recharging efficiency. At low speeds, the TCU controls the transmission to engage first gear to maintain sufficient driving torque; at high speeds, the TCU controls the transmission to engage second gear to ensure the engine operates within its economic range, while P1 motor 40 continuously generates electricity. This mode effectively solves the problem of continuous battery drain during long-distance off-road driving, ensuring the range of the hybrid system.

[0072] Of the five operating modes mentioned above, the electronic locking differential can be activated independently in any mode, locking the differential at any time as needed for off-road conditions to force synchronization of the left and right drive shafts and ensure effective transmission of driving force in extreme terrain. The electronic oil pump operates continuously during transmission operation, providing active lubrication to all transmission components, which is particularly important in low-speed, high-torque off-road conditions, effectively preventing gear wear and bearing damage caused by insufficient lubrication.

[0073] The purpose of this invention is to provide a hybrid transmission, a hybrid transmission system, and a vehicle to solve the technical problems in the prior art where a single-motor hybrid transmission cannot achieve all-scenario four-wheel drive when the power battery is depleted, and where a dual-motor single-speed hybrid transmission cannot simultaneously achieve low-speed high-torque passability and high-speed fuel economy.

[0074] By dividing the functions of the P1 motor and the P3 motor, the P1 motor is dedicated to generating electricity and the P3 motor is dedicated to driving. The two functions do not interfere with each other, so that when the power battery is depleted, the P1 motor generates electricity while the P3 motor can still drive the front axle. Together with the rear axle drive system, it can achieve all-scenario four-wheel drive, fundamentally solving the structural defect of the front axle losing driving force when the single motor hybrid box is depleted.

[0075] The two-speed transmission mechanism switches between a first gear pair (high gear ratio) and a second gear pair (low gear ratio). In engine direct drive mode, it engages the high gear ratio at low speeds to obtain greater output torque and improve off-road capability. At high speeds, it engages the low gear ratio to keep the engine operating in the economic speed range and improve fuel economy. This achieves an organic unity between low-speed high torque and high-speed economy.

[0076] The integrated electronic locking differential further locks the differential, ensuring consistent speeds for both left and right wheels, significantly improving vehicle passability under extreme off-road conditions.

[0077] Example 2 This embodiment provides a hybrid transmission system. The hybrid transmission, as described in Embodiment 1, is integrated at the system level with the engine 10, dual-mass flywheel 20, power battery 30, and drive shaft to construct a complete hybrid power transmission system for the front axle of a rugged off-road vehicle.

[0078] The hybrid transmission system of this embodiment includes five core components: an engine 10, a dual-mass flywheel 20, a hybrid transmission, a power battery 30, and a drive shaft. The engine 10 serves as the system's thermal power source, and its output is connected to the input shaft 43 of the hybrid transmission via the dual-mass flywheel 20. The power battery 30 serves as the system's electrical energy storage unit, connected to the dual electronic controls in the hybrid transmission via a high-voltage wiring harness, providing electrical energy to the P3 motor 50 and storing the electrical energy generated by the P1 motor 40. The drive shaft connects the output ends of the differential 60 on both sides, transmitting the power output from the transmission to the left and right wheels 70 of the front axle.

[0079] The dual-mass flywheel 20 plays a crucial role in vibration damping and isolation within this system. During operation, the engine 10 generates periodic torque fluctuations. If these fluctuations are directly transmitted to the transmission input shaft 43, they will cause impact loads on the transmission gear pairs, accelerating gear wear and generating significant transmission noise and vibration. The dual-mass flywheel 20, through its internal spring damping system, effectively attenuates and filters the torque fluctuations from the engine 10 before they are transmitted to the input shaft 43, significantly reducing the dynamic load transmitted to the transmission, protecting the service life of the transmission gear pairs and bearings, and simultaneously improving the overall NVH (noise, vibration, and harshness) performance of the vehicle.

[0080] For hardcore off-road vehicles, the engine 10 frequently operates at low speeds and high loads under off-road conditions, resulting in particularly severe torque fluctuations. The vibration isolation function of the dual-mass flywheel 20 is even more crucial in this scenario. The main mass of the dual-mass flywheel 20 is connected to the crankshaft flange of the engine 10, while the secondary mass is connected to the input shaft 43 of the hybrid transmission via a spline. The two mass blocks are connected by an arc spring and a damping mechanism, forming a torsional vibration system with a specific resonant frequency. This isolates the main excitation frequency of the engine 10 from the operating speed range of the transmission system.

[0081] In the system-level four-wheel drive implementation scheme, the hybrid transmission system in this embodiment serves as the front axle drive unit, forming a full-time four-wheel drive architecture together with the vehicle's rear axle drive system. The front axle is driven by this hybrid transmission system, while the rear axle is driven by an independent drive motor or a conventional driveshaft.

[0082] When the power battery 30 is fully charged, both the P3 motor 50 and the rear axle drive system are in operation, and the front and rear axles output driving force simultaneously to achieve four-wheel drive mode when fully charged. When maximum driving force is required, the engine 10 can also drive the front axle together with the P3 motor 50 in parallel mode to further enhance the driving force of the front axle and achieve super four-wheel drive performance in coordination with the rear axle.

[0083] When the power battery 30% is depleted, the four-wheel drive maintenance scheme of this system fully demonstrates the core value of the dual-motor division of labor. When the power battery 30% charge drops to a set threshold, the vehicle control system switches to the depleted four-wheel drive mode. When the engine 10 starts, it drives the P1 motor 40 to generate electricity in series mode. The electrical energy generated by the P1 motor 40 is directly transmitted to the P3 motor 50 through dual electronic control. The P3 motor 50 uses the electrical energy generated by the P1 motor 40 in real time to continuously drive the front axle. At the same time, the rear axle drive system continues to work, and both the front and rear axles maintain driving force output, thus maintaining all-scenario four-wheel drive.

[0084] During this process, the balance between the power generation of P1 motor 40 and the driving power of P3 motor 50 is coordinated by the dual-electric control strategy to ensure that P3 motor 50 receives a stable power supply and that the front axle driving force is not interrupted due to power failure. The realization of this power-fed four-wheel drive scheme relies entirely on the physical independence of P1 motor 40 and P3 motor 50 and the independent control capability of the dual-electric control system at the electrical level, which is the core application scenario of the dual-motor division of labor arrangement of this invention.

[0085] In practical applications of rugged off-road vehicles, the hybrid transmission system of this embodiment can intelligently switch operating modes according to different driving conditions. On urban roads, the system prioritizes pure electric drive to reduce energy consumption and emissions. On suburban roads, the system uses engine direct drive combined with battery replenishment, maintaining a 30% charge level in the battery while driving. On off-road terrain, the system flexibly switches between series drive, parallel drive, or engine direct drive modes based on road conditions and driver needs, and activates the electronic locking differential when necessary to ensure vehicle passability in extreme terrain. The entire system's mode switching is uniformly coordinated by the vehicle control system and is transparent to the driver, who only needs to focus on driving operations without manual intervention in switching power modes.

[0086] Example 3 This embodiment provides a vehicle that utilizes a hybrid transmission system as described in Embodiment 2, which is mounted on a hardcore off-road vehicle platform to achieve all-scenario driving capability and comprehensive performance optimization for complex off-road terrain.

[0087] The vehicles in this embodiment include, but are not limited to, rugged off-road SUVs, off-road pickup trucks, and professional off-road vehicles with a longitudinally mounted engine layout. These vehicles share common characteristics: they employ a non-load-bearing body or a reinforced load-bearing body, are equipped with independent or non-independent suspension, have a large ground clearance, and are designed to meet the passability requirements of extreme off-road terrains such as deserts, mountains, mud, and water crossings.

[0088] In typical off-road vehicle usage scenarios, the powertrain faces extremely complex operating challenges. In desert terrain, vehicles need to maintain low speeds on soft sand, where driving resistance is much higher than on hard surfaces, and the coefficient of friction is low, placing high demands on the distribution of driving force between the front and rear axles and the coordinated use of differential locks. In mountainous terrain, vehicles need to start and climb steep slopes, requiring the transmission to provide sufficient low-speed torque, while engine braking is needed when descending. In muddy terrain, the coefficient of friction between the left and right wheels differs greatly, and the differential function in this scenario can cause the driving force of the wheel with better traction to be "stolen," which must be overcome by using a differential lock. In water wading conditions, vehicles need to maintain stable low-speed driving in water, requiring high levels of smoothness and reliability of the driving force.

[0089] The aforementioned extreme operating conditions place comprehensive and stringent demands on the performance of hybrid transmission systems, which are precisely the core application scenarios targeted by this invention.

[0090] The vehicle in this embodiment is equipped with a hybrid transmission system as described in Embodiment 2. The front axle is driven by this hybrid transmission system, while the rear axle is driven by an independent drive system, with the front and rear axles together forming a four-wheel drive architecture. In off-road conditions, the driver can select to activate the electronic locking differential according to the terrain conditions, locking the front axle differential 60° to ensure that the left and right wheels of the front axle rotate at the same speed. Combined with the rear axle differential lock as configured, this achieves a fully locked front and rear axle extreme off-road mode, maximizing the vehicle's passability in extreme terrain.

[0091] In desert off-road conditions, the vehicle typically travels at a low speed continuously. The vehicle control system selects the optimal driving mode based on the charge status of the power battery 30. When the power battery 30 has sufficient charge, the system uses either pure electric drive mode or parallel drive mode. The P3 motor 50 provides smooth low-speed torque output, preventing drive force vibration caused by engine 10 speed fluctuations when driving on sand. When the power battery 30 has insufficient charge, the system switches to series drive mode. The engine 10 drives the P1 motor 40 to generate electricity, and the P3 motor 50 uses the generated electricity to continuously drive the front axle, working in conjunction with the rear axle to maintain four-wheel drive. During continuous desert off-roading, the electronic locking differential can be selectively activated based on the softness of the sand. When the sand is particularly soft and there is a significant difference in traction between the left and right wheels, the differential lock is activated to ensure effective transmission of drive force. The two-speed transmission engages first gear during low-speed desert off-roading, amplifying the output torque through a high gear ratio to provide sufficient low-speed drive force to overcome sand resistance.

[0092] In off-road mountain conditions, vehicles need to start on steep slopes and climb at low speeds, making the demand for low-speed torque extremely prominent. The hybrid transmission system in this embodiment utilizes the first gear of a two-speed transmission mechanism to further amplify the torque output from the engine 10 through a large gear ratio. Combined with the low-speed, high-torque characteristics of the P3 motor 50, this provides the vehicle with sufficient driving force for climbing. When starting on steep slopes, the zero-speed, high-torque characteristics of the P3 motor 50 are particularly prominent. The motor can output near-peak torque at zero speed, enabling the vehicle to start smoothly on steep slopes without slipping – a performance advantage difficult to achieve with traditional engine-transmission systems. During downhill driving, the braking force of the engine 10 and the regenerative braking force of the P3 motor 50 work together to provide sufficient downhill braking force, while simultaneously recovering braking energy to the power battery 30, improving system energy utilization efficiency.

[0093] In muddy off-road conditions, the electronic dog clutch differential lock plays a crucial role. On muddy surfaces, the difference in traction coefficients between the left and right wheels is significant. Without locking the differential 60, driving force is concentrated on the wheel with lower traction, causing it to spin freely while the wheel with higher traction receives no driving force, leading to the vehicle getting stuck. Activating the electronic dog clutch differential lock forces the output ends of the differential 60 to rotate synchronously, effectively transferring driving force to the wheel with higher traction and propelling the vehicle out of trouble. The high locking torque characteristic of the dog clutch differential lock ensures reliable locking under high-resistance conditions in muddy conditions, preventing slippage due to excessive torque.

[0094] Under highway driving conditions, the vehicle in this embodiment fully utilizes the fuel economy advantages of the two-speed transmission. The vehicle control system switches to engine direct drive mode, and the TCU controls the shifting system to engage the transmission in second gear with a low gear ratio. The engine 10 drives the vehicle at a lower speed, with the operating point falling within the economic speed range, significantly reducing fuel consumption. During high-speed cruising, the P1 motor 40 can selectively generate a small amount of electricity based on the state of charge of the power battery 30 to maintain the power battery 30's charge level and reserve energy for the next stage of off-road driving.

[0095] Vehicles equipped with the hybrid transmission system of this embodiment exhibit significantly improved overall performance in the following dimensions: In terms of off-road capability, the low-speed high torque output capability of the two-speed transmission mechanism, the forced locking function of the electronic dog clutch differential lock, and the continuous maintenance capability of all-scenario four-wheel drive together constitute a powerful off-road capability guarantee system. In terms of fuel economy, the optimized transmission ratio of the two-speed transmission mechanism under high-speed conditions, the free adjustment of the engine operating point in series mode, and the energy recovery of the P3 motor regenerative braking together achieve the comprehensive energy-saving effect of the hybrid system. In terms of reliability, the electronic oil pump active lubrication system ensures that the transmission is fully lubricated under various operating conditions, the dual-mass flywheel effectively isolates engine torque fluctuations, and the large locking torque of the electronic dog clutch differential lock ensures reliable locking under off-road conditions. These triple reliability protection measures significantly extend the service life of the transmission system. In terms of driving experience, the intelligent switching between multiple working modes is transparent to the driver, allowing the driver to focus on off-road driving operations. The system automatically selects and switches the optimal working mode, reducing driving difficulty and enhancing driving pleasure.

[0096] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0097] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A hybrid transmission, characterized in that, include: A two-speed transmission mechanism, comprising an input shaft, a first output shaft, a second output shaft, a first gear pair, and a second gear pair, wherein the input shaft is connected to the first output shaft and the second output shaft via the first gear pair or the second gear pair; P1 motor, the P1 motor having a P1 motor shaft, the P1 motor shaft being connected to the input shaft via an idler wheel shaft, the P1 motor being used to convert mechanical energy into electrical energy for power generation; The P3 motor has a P3 motor shaft, which is connected to a first output shaft and a second output shaft. The P3 motor is used to convert electrical energy into mechanical energy to drive the vehicle.

2. The hybrid transmission as described in claim 1, characterized in that, It also includes dual electronic control, used to independently control the P1 motor and the P3 motor; The dual electric control system includes a P1 electric control and a P3 electric control. The P1 electric control is electrically connected to the P1 motor, and the P3 electric control is electrically connected to the P3 motor.

3. The hybrid transmission as described in claim 2, characterized in that, The dual electronic control system is electrically connected to the power battery. The electrical energy generated by the P1 motor is stored in the power battery via the P1 electronic control system, and the electrical energy stored in the power battery is output to the P3 motor via the P3 electronic control system.

4. The hybrid transmission as described in claim 1, characterized in that, It also includes a gear shifting system, wherein the transmission ratio of the second gear pair is less than the transmission ratio of the first gear pair.

5. The hybrid transmission as described in claim 1, characterized in that, It also includes a differential, which is connected to the first output shaft and the second output shaft, and the two output ends of the differential are respectively connected to the left drive shaft and the right drive shaft.

6. The hybrid transmission as described in claim 5, characterized in that, It also includes an electronic dog clutch differential lock, which is connected to the differential and used to lock the differential so that the output speeds on both sides of the differential are kept consistent.

7. The hybrid transmission as described in claim 1, characterized in that, It also includes a shifting system, which is connected to a two-speed transmission mechanism and is used to switch the transmission state between the first gear pair and the second gear pair and realize the switching between N gear, first gear and second gear; The shifting system includes a shift motor, a shift hub, and a shift fork. The shift motor drives the shift hub to rotate, and the shift hub drives the shift fork to shift the two-speed transmission mechanism between N gear, first gear, and second gear.

8. The hybrid transmission as claimed in claim 1, characterized in that, It also includes an electronic oil pump, which is connected to the mechanical transmission part of the two-speed transmission mechanism and is used to actively lubricate the two-speed transmission mechanism; The electronic oil pump integrates a drive motor and a controller. The controller controls the drive motor to drive the electronic oil pump through independent software, so as to provide lubricating oil to the mechanical transmission part of the two-speed transmission mechanism.

9. A hybrid power transmission system, characterized in that, include: An engine and a dual-mass flywheel, wherein the dual-mass flywheel is connected to the output end of the engine; The hybrid transmission as described in any one of claims 1-7, wherein the input shaft of the hybrid transmission is connected to the dual-mass flywheel drive; The power battery is electrically connected to the P1 motor and P3 motor in the hybrid transmission. And a drive shaft, which is connected to the output of the differential in the hybrid transmission for transmitting power to the wheels.

10. A vehicle, characterized in that, Includes the hybrid transmission system as described in claim 9.

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