Two-section continuously variable transmission device for tractor and vehicle

Abstract

The present invention relates to the technical field of tractor transmissions, and more specifically, to a two-range continuously variable transmission for tractors and a vehicle thereof. The transmission comprises: a first motor and a second motor, respectively disposed at the front and rear ends of a transmission shaft; a double-linked planetary gear mechanism, disposed on the transmission shaft and located between the first and second motors, the double-linked planetary gear mechanism comprising a splitter planet carrier, left planetary gears, right planetary gears, a left sun gear, and a right sun gear; and two wet clutches, a first wet clutch and a second wet clutch, disposed on the transmission shaft and located behind the double-linked planetary gear mechanism, respectively used to control power transmission between a high-speed range and a low-speed range, controlling the engagement and disengagement of the first and second wet clutches to achieve uninterrupted power shifting between the two ranges. The transmission can shift gears without disconnecting the power supply, thus preventing normal vehicle travel and interrupting operation.

Description

Technical Field

[0001] The present invention relates to the technical field of tractor transmission devices, and in particular to a two-section continuously variable transmission device for a tractor and a vehicle. Background Art

[0002] Agricultural tractors are essential machinery in agricultural production, and the performance of their powertrains directly impacts operational efficiency and operator experience. Continuously variable transmission technology, a key technology for improving tractor performance, has undergone multiple stages of development. Early CVTs primarily employed hydrostatic transmission units, achieving stepless speed regulation through a combination of a hydraulic pump and a hydraulic motor. While this solution met basic requirements, it suffered from limitations such as low transmission efficiency and system complexity. Advances in power electronics have led to the emergence of transmissions that utilize generators and electric motors to achieve stepless speed regulation. These solutions are categorized as single-range and dual-range (two-range) in terms of speed regulation. However, most of these solutions are based on the existing hydrostatic transmission architecture, resulting in a complex and bulky transmission structure and a high reliance on mechanical transmission technology. In particular, dual-range CVTs often employ an AMT (automatic mechanical transmission) mechanism for range shifting. This shifting method requires power disconnection during the shift process, causing the vehicle to lose speed while driving or even stall during operation, severely impacting operational efficiency and operator experience. Summary of the Invention

[0003] The object of the present invention is to provide a two-section continuously variable transmission device for a tractor, which can shift gears in sections of the vehicle without disconnecting the power, without affecting the normal driving of the vehicle and without causing interruption of operation.

[0004] Another object of the present invention is to provide a vehicle that can shift gears in sections without disconnecting the power supply, which will not affect the normal driving of the vehicle and will not cause operation interruption.

[0005] The technical solution of the present invention is achieved as follows:

[0006] A two-section continuously variable transmission device for a tractor, comprising a gearbox and a gearbox shaft, wherein the input end of the gearbox shaft is connected to the output end of an engine for transmission, and further comprising:

[0007] At least two motors, namely a first motor and a second motor, which are respectively arranged at the front and rear ends of the gearbox shaft;

[0008] a double planetary gear mechanism, disposed on the gearbox shaft and located between the first motor and the second motor, the double planetary gear mechanism comprising a splitter planet carrier, a left planetary gear, a right planetary gear, a left sun gear, and a right sun gear;

[0009] There are two wet clutches, namely a first wet clutch and a second wet clutch. The first wet clutch and the second wet clutch are respectively arranged on the transmission shaft and located behind the double planetary gear mechanism. The first wet clutch and the second wet clutch are used to control the power transmission in the high-speed section and the low-speed section respectively. By controlling the engagement and disengagement of the first wet clutch and the second wet clutch, power shifting between the two sections is achieved without interruption of power transmission.

[0010] Furthermore, it also includes a battery module, and the battery module is electrically connected to the first motor and the second motor.

[0011] Furthermore, the two-section continuously variable transmission device has a mechanical speed change mode;

[0012] When the engine is started and the first motor is in the low-speed lock state, the vehicle is in the mechanical transmission mode, and the power transmission route is:

[0013] If the first wet clutch is locked, power is transmitted from the engine to the splitter planetary carrier, then to the left sun gear through the left planetary gear, and finally to the drive wheel through the second wet clutch;

[0014] If the second wet clutch is locked, power is transmitted from the engine to the splitter planetary carrier, then to the right sun gear through the right planetary gear, and finally to the drive wheel through the first wet clutch.

[0015] Furthermore, the two-section continuously variable transmission has a pure electric drive mode;

[0016] When the engine is turned off and the battery module is fully charged, the vehicle is in the pure electric drive mode, and the power transmission route is:

[0017] If the second wet clutch is locked, the first motor draws power from the battery module and transmits it to the double planetary gear mechanism through the ring gear. The power is then transmitted from the left planetary gear to the left sun gear and then to the drive wheel through the second wet clutch.

[0018] If the first wet clutch is locked, the first motor draws power from the battery module and transmits it to the double planetary gear mechanism through the ring gear. The power is then transmitted from the right planetary gear to the right sun gear and then to the drive wheel through the first wet clutch.

[0019] The second motor draws electricity from the battery module to provide power and torque supplementation according to the power requirements of the entire vehicle.

[0020] Furthermore, the two-section continuously variable transmission device has a kinetic energy recovery mode. When the vehicle is in the kinetic energy recovery mode, the first motor and the second motor are both in a power generation state. The power transmission route in the kinetic energy recovery mode is opposite to the power transmission route in the pure electric drive mode, so as to convert the vehicle's kinetic energy into electrical energy and store it in the battery module.

[0021] Furthermore, the two-section continuously variable transmission device has a hybrid continuously variable transmission mode of oil-electric parallel flow;

[0022] The engine is started, and the vehicle is in the oil-electric parallel flow hybrid continuously variable transmission mode, and the power transmission route is:

[0023] If the second wet clutch is locked, the engine power is divided into two paths through the split planetary carrier, one of which is transmitted to the left sun gear through the left planetary gear, and the other is transmitted to the first motor through the ring gear, and stepless regulation is achieved by adjusting the speed of the first motor;

[0024] If the first wet clutch is locked, the engine power is divided into two paths through the split planetary carrier, one of which is transmitted to the right sun gear through the right planetary gear, and the other is transmitted to the first motor through the ring gear. Stepless regulation is achieved by adjusting the speed of the first motor.

[0025] Furthermore, the first motor, the second motor, the double planetary gear mechanism, the first wet clutch and the second wet clutch are arranged inside the gearbox.

[0026] A vehicle is a tractor, comprising the two-section continuously variable transmission device for a tractor.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention designs a compact two-section continuously variable transmission device for tractors, which uses a double-linked planetary gear mechanism and two wet clutches (a first wet clutch and a second wet clutch). When the vehicle shifts between the high-speed section and the low-speed section, the first wet clutch and the second wet clutch operate simultaneously. Through brief simultaneous sliding, power is not interrupted during the gear switching process, thereby achieving stepless adjustment of the two speed change sections without affecting the normal driving of the vehicle or causing operation interruptions, ensuring smooth operation of the vehicle. The overall layout is simple and compact, the number of gears is small, and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 Schematic diagram of the structure of a two-section continuously variable transmission device in embodiment 1 of the present invention;

[0031] Figure 2 Schematic diagram of the structure of a two-section continuously variable transmission device in embodiment 2 of the present invention.

[0032] In the picture:

[0033] 1-Engine; 2-First motor; 3-Second motor; 4-Dual planetary gear mechanism;

[0034] C1-first wet clutch; C2-second wet clutch;

[0035] 5-Battery module; 6-Gearbox shaft. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0038] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0039] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" and the like indicate positions or locations based on the positions shown in the accompanying drawings, or the positions or locations in which the inventive product is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and to simplify the description, and are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0040] Furthermore, terms such as "horizontal," "vertical," and "overhanging" do not necessarily imply that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0041] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0042] The following embodiments of the present invention are described in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0043] Example 1

[0044] Traditional agricultural tractors use hydrostatic transmission or generator + electric motor stepless speed regulation technology. Although these technologies can achieve stepless speed change, they have the following problems:

[0045] 1. Complex structure and bulky size: It requires complex mechanical and hydraulic components, which causes the entire gearbox to take up a large space.

[0046] 2. Dependence on traditional mechanical gearbox technology: High reliance on existing mechanical gearboxes increases costs and maintenance difficulties.

[0047] 3. Power interruption during gear shifting: Currently, most two-stage continuously variable transmissions on the market use an AMT (automatic mechanical transmission) mechanism. Power must be disconnected during gear shifting, which can cause the vehicle to slow down or even stop while driving, affecting operating efficiency.

[0048] To address these issues, the present invention proposes a new design concept: a dual-planetary convergence mechanism combined with two wet clutches to achieve a two-section continuously variable transmission while supporting multiple operating modes, as follows:

[0049] Reference Figure 1 A two-section continuously variable transmission device for a tractor includes a gearbox and a gearbox shaft 6, wherein the input end of the gearbox shaft 6 is connected to the output end of the engine 1 for transmission, and further includes:

[0050] At least two motors, namely a first motor 2 and a second motor 3, are respectively arranged at the front and rear ends of the gearbox shaft 6, and the two motors are respectively used to achieve power output and energy recovery in multiple working modes;

[0051] a double planetary gear mechanism 4, disposed on the transmission shaft 6 and located between the first motor 2 and the second motor 3, the double planetary gear mechanism 4 comprising a splitter planet carrier, a left planetary gear, a right planetary gear, a left sun gear, and a right sun gear;

[0052] A first wet clutch C1 and a second wet clutch C2 are disposed on the transmission shaft 6 and located behind the double planetary gear mechanism 4. The first wet clutch C1 and the second wet clutch C2 are used to control power transmission in the high-speed section and the low-speed section, respectively. By controlling the engagement and disengagement of the first wet clutch C1 and the second wet clutch C2, power shifting between the two sections is achieved without interruption of power transmission.

[0053] A battery module 5 , wherein the battery module 5 is electrically connected to the first motor 2 and the second motor 3 .

[0054] The present invention realizes two-section continuously variable transmission through a compact design, the core of which lies in the following points:

[0055] 1. Double planetary gear mechanism 4:

[0056] This structure is equivalent to an "intelligent transfer case", which can divide the power of engine 1 into two paths and transmit it to different gear sets.

[0057] By controlling the two wet clutches (the first wet clutch C1 and the second wet clutch C2), the low-speed section and the high-speed section can be switched to achieve stepless speed change.

[0058] 2. Two motors work together:

[0059] There are two motors in the system (the first motor 2 and the second motor 3), which can work independently or in coordination.

[0060] For example, in pure electric drive mode, the motor can draw electricity directly from the battery to drive the vehicle; in kinetic energy recovery mode, the motor can also generate electricity and store energy in the battery.

[0061] 3. Four working modes:

[0062] Mechanical transmission mode: Engine 1 is started, the motor is locked, and the vehicle operates using traditional mechanical transmission.

[0063] Pure electric driving mode: Engine 1 is turned off and the vehicle is driven entirely by battery power.

[0064] Kinetic energy recovery mode: Use the motor to convert the vehicle's kinetic energy into electrical energy and store it.

[0065] Hybrid mode: Engine 1 and the electric motor work together to provide stronger power output.

[0066] 4. Power shifting without interruption:

[0067] When switching between low-speed and high-speed sections, the coordinated action of the two wet clutches ensures that power will not be interrupted during the gear shifting process, improving driving experience and work efficiency.

[0068] The following details the four working modes:

[0069] (1) Mechanical speed change mode

[0070] When the engine 1 is started and the first motor 2 is in the low-speed lock state, the vehicle is in the mechanical transmission mode, and its power transmission route is:

[0071] If the first wet clutch C1 is locked, power is transmitted from the engine 1 to the splitter planetary carrier, then to the left sun gear through the left planetary gear, and finally to the drive wheel through the second wet clutch C2, completing power transmission in the low-speed range.

[0072] If the second wet clutch C2 is locked, power is transmitted from the engine 1 to the split planetary carrier, then to the right sun gear through the right planetary gear, and finally to the drive wheel through the first wet clutch C1, completing power transmission in the high-speed section.

[0073] (2) Pure electric drive mode

[0074] When the engine 1 is turned off and the battery module 5 is fully charged, the vehicle is in the pure electric drive mode. The two motors can directly drive the vehicle and reverse the vehicle by reversing. The power transmission route is:

[0075] If the second wet clutch C2 is locked, the first motor 2 draws power from the battery module 5 and transmits it to the double planetary gear mechanism 4 through the ring gear. The power is then transmitted from the left planetary gear to the left sun gear and then to the drive wheel through the second wet clutch C2.

[0076] If the first wet clutch C1 is locked, the first motor 2 draws power from the battery module 5 and transmits it to the double planetary gear mechanism 4 through the ring gear. The power is then transmitted from the right planetary gear to the right sun gear and then to the drive wheel through the first wet clutch C1.

[0077] The second motor 3 draws power and torque from the battery module 5 according to the power requirements of the vehicle. The two motors draw power directly from the battery module 5 to drive the vehicle, and then reverse the motor to achieve reverse movement.

[0078] (3) Kinetic energy recovery mode

[0079] When the vehicle is in the kinetic energy recovery mode, the first motor 2 and the second motor 3 are both in the power generation state. The power transmission route in the kinetic energy recovery mode is opposite to the power transmission route in the pure electric drive mode (the details are not repeated here). The energy during vehicle deceleration is converted into electrical energy and stored in the battery module 5, so that the kinetic energy of the vehicle is converted into electrical energy and stored in the battery module 5.

[0080] (4) Hybrid continuous variable transmission mode

[0081] Engine 1 is started, the vehicle is in the oil-electric parallel flow hybrid continuously variable transmission mode, and the power transmission route is:

[0082] If the second wet clutch C2 is locked, the power of the engine 1 is divided into two paths through the split planetary carrier. One path is transmitted to the left sun gear through the left planetary gear, and the other path is transmitted to the first motor 2 through the ring gear. By adjusting the speed of the first motor 2, stepless regulation is achieved.

[0083] If the first wet clutch C1 is locked, the power of the engine 1 is divided into two paths through the split planetary carrier, one of which is transmitted to the right sun gear through the right planetary gear, and the other is transmitted to the first motor 2 through the ring gear. Stepless regulation is achieved by adjusting the speed of the first motor 2.

[0084] In the oil-electric parallel hybrid continuously variable transmission mode, by adjusting the speed of the first motor 2, the output speed can be steplessly adjusted while the speed of the engine 1 remains unchanged. The excess power can be converted into electrical energy by the first motor 2 and stored in the battery module 5.

[0085] It should be noted that the basic principles of oil-electric parallel flow hybrid are:

[0086] Hybrid powertrain technology is a hybrid technology that effectively combines the power of the engine 1 and the electric motor to achieve efficient operation through energy management strategies. In this mode, the vehicle can choose from the following drive modes based on actual operating conditions:

[0087] 1. Motor drive only: Suitable for low speed, starting stage or situations where the vehicle needs to be temporarily moved, saving fuel and avoiding frequent hot starts.

[0088] 2. Engine 1 only: Suitable for road transfer conditions, giving full play to the efficiency advantage of Engine 1.

[0089] 3. The motor is driven together with the engine 1: This is suitable for scenarios that require high torque output (such as sudden increase in field load and climbing).

[0090] The application of a continuously variable transmission (CVT) further optimizes power transmission efficiency, enabling the engine 1 and the motor to work together under optimal working conditions.

[0091] In parallel flow mode, the motor and engine 1 may drive the vehicle simultaneously, as follows:

[0092] (1) High load conditions

[0093] When the vehicle is under high load (such as when suddenly loading a field, climbing a slope, or driving with a heavy load), the control system instructs engine 1 and the electric motor to output power simultaneously. This "parallel" mode significantly improves the vehicle's dynamic performance and meets instantaneous high power demands.

[0094] (2) Energy optimization mode

[0095] In some cases, to maximize fuel economy, the system may allow Engine 1 and the motor to drive the wheels together, but the division of labor is different: Engine 1 is responsible for providing basic power, and the motor supplements the additional required torque to prevent Engine 1 from entering an inefficient working range.

[0096] (3) Recovering braking energy

[0097] During deceleration or braking, the motor can act as a generator to recover energy and store it in the battery. If the driver continues to depress the accelerator pedal, the system may reactivate engine 1 and the motor to drive together.

[0098] In this embodiment, the first motor 2 , the second motor 3 , the double planetary gear mechanism 4 , the first wet clutch C1 , and the second wet clutch C2 are disposed inside the transmission.

[0099] In summary, this invention addresses the complex structure, high cost, and power interruption associated with existing two-stage continuously variable transmission technology for tractors. It provides a small, compact, low-cost, and power-shifting solution. Furthermore, it supports multiple operating modes to meet the needs of diverse scenarios, demonstrating high practical value and market competitiveness.

[0100] Example 2

[0101] Reference Figure 2 A two-section continuously variable transmission device for a tractor includes a gearbox and a gearbox shaft 6, wherein the input end of the gearbox shaft 6 is connected to the output end of the engine 1 for transmission, and further includes:

[0102] A double planetary gear mechanism 4 is provided on the transmission shaft 6, and the double planetary gear mechanism 4 includes a splitter planet carrier, a left planetary gear, a right planetary gear, a left sun gear, and a right sun gear;

[0103] The first wet clutch C1 and the second wet clutch C2 are arranged on the transmission shaft 6 and are located behind the double planetary gear mechanism 4. The first wet clutch C1 and the second wet clutch C2 are used to control the power transmission in the high-speed section and the low-speed section respectively. By controlling the engagement and disengagement of the first wet clutch C1 and the second wet clutch C2, power shifting between the two sections is achieved without interruption of power transmission.

[0104] At least two motors, namely a first motor 2 and a second motor 3, are respectively arranged outside the gearbox, the first motor 2 is connected to the front end of the gearbox shaft 6 through a first transmission assembly, and the second motor 3 is connected to the rear end of the gearbox shaft 6 through a second transmission assembly;

[0105] A battery module 5 , wherein the battery module 5 is electrically connected to the first motor 2 and the second motor 3 .

[0106] The two-section continuously variable transmission device has a mechanical speed change mode, a pure electric drive mode, a kinetic energy recovery mode and a hybrid continuously variable speed change mode;

[0107] Among them, when the engine 1 is started and the first motor 2 is in a low-speed lock state, the vehicle is in the mechanical transmission mode; when the engine 1 is turned off and the battery module 5 is sufficiently charged, the vehicle is in the pure electric drive mode; when the vehicle is in the kinetic energy recovery mode, the first motor 2 and the second motor 3 are both in a power generation state, converting the vehicle's kinetic energy into electrical energy and storing it in the battery module 5; when the vehicle is in a hybrid continuously variable transmission mode, it is used to effectively combine the power of the engine 1 and the motor.

[0108] In summary, compared with Example 1, this embodiment is still based on the same technical principles and also has four operating modes. The difference is that in this embodiment, the two motors are externally located and parallel to the gearbox shaft 6. This solution is suitable for situations where the axial space of the gearbox is limited or there is insufficient space along the gearbox shaft 6.

[0109] Example 3

[0110] A vehicle is a tractor, comprising the two-section continuously variable transmission device for a tractor.

[0111] The beneficial effects of the technical solution of the present invention are:

[0112] Compared with the existing technical solutions, the present invention has the following significant advantages:

[0113] 1. Small size and compact structure: Due to the use of a double planetary gear mechanism 4 and two wet clutches, the overall design is more concise, reducing the number of gears and the size.

[0114] 2. Low cost: Simplified mechanical structure, reduced manufacturing and maintenance costs.

[0115] 3. Uninterrupted power during gear shifting: This solves the problem of power interruption during gear shifting in traditional transmissions and improves operation continuity.

[0116] 4. Multiple operating modes: Supports mechanical speed change, pure electric drive, kinetic energy recovery, and hybrid operation to meet different working conditions.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

[0118] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A two-section continuously variable transmission device for a tractor, comprising a gearbox and a gearbox shaft (6), wherein the input end of the gearbox shaft (6) is connected to the output end of the engine (1) for transmission, characterized in that: Also includes: At least two motors, namely a first motor (2) and a second motor (3), which are respectively arranged at the front and rear ends of the gearbox shaft (6); A double planetary gear mechanism (4) is provided on the gearbox shaft (6) and is located between the first motor (2) and the second motor (3), the double planetary gear mechanism (4) comprising a split planet carrier, a left planetary gear, a right planetary gear, a left sun gear, and a right sun gear; Two wet clutches, namely a first wet clutch (C1) and a second wet clutch (C2), the first wet clutch (C1) and the second wet clutch (C2) being respectively arranged on a gearbox shaft (6) and located behind the double-linked planetary gear mechanism (4), the first wet clutch (C1) and the second wet clutch (C2) being respectively used to control power transmission in a high-speed section and a low-speed section, and by controlling the engagement and disengagement of the first wet clutch (C1) and the second wet clutch (C2), power shifting between the two sections is achieved without interruption of power transmission; It also includes a battery module (5), wherein the battery module (5) is electrically connected to the first motor (2) and the second motor (3); When the engine (1) is started and the first motor (2) is in a low-speed locked state, the vehicle is in a mechanical speed change mode, and the power transmission route is: If the first wet clutch (C1) is locked, power is transmitted from the engine (1) to the split planetary carrier, then transmitted to the left sun gear through the left planetary gear, and then transmitted to the drive wheel through the second wet clutch (C2); If the second wet clutch (C2) is locked, power is transmitted from the engine (1) to the split planetary carrier, then transmitted to the right sun gear through the right planetary gear, and then transmitted to the drive wheel through the first wet clutch (C1); When the engine (1) is turned off and the battery module (5) is fully charged, the vehicle is in a pure electric drive mode, and the power transmission route is: If the second wet clutch (C2) is locked, the first motor (2) draws power from the battery module (5) to output power, which is transmitted to the double planetary gear mechanism (4) through the ring gear. The power is then transmitted from the left planetary gear to the left sun gear, and then transmitted to the drive wheel through the second wet clutch (C2); If the first wet clutch (C1) is locked, the first motor (2) draws power from the battery module (5) to output power, which is transmitted to the double planetary gear mechanism (4) through the ring gear. The power is then transmitted from the right planetary gear to the right sun gear, and then transmitted to the drive wheel through the first wet clutch (C1); The second motor (3) draws electricity from the battery module (5) to provide power and torque supplementation according to the power requirements of the entire vehicle; The engine (1) is started, the vehicle is in the oil-electric parallel flow hybrid continuously variable transmission mode, and the power transmission route is: If the second wet clutch (C2) is locked, the power of the engine (1) is divided into two paths through the split planetary carrier, one of which is transmitted to the left sun gear through the left planetary gear, and the other is transmitted to the first motor (2) through the ring gear, and stepless regulation is achieved by adjusting the speed of the first motor (2); If the first wet clutch (C1) is locked, the power of the engine (1) is divided into two paths through the split planetary carrier, one of which is transmitted to the right sun gear through the right planetary gear, and the other is transmitted to the first motor (2) through the ring gear, and stepless regulation is achieved by adjusting the speed of the first motor (2).

2. The two-range continuously variable transmission according to claim 1, characterized in that: The two-section continuously variable transmission device has a kinetic energy recovery mode. When the vehicle is in the kinetic energy recovery mode, the first motor (2) and the second motor (3) are both in a power generation state. The power transmission route in the kinetic energy recovery mode is opposite to the power transmission route in the pure electric drive mode, so as to convert the vehicle's kinetic energy into electrical energy and store it in the battery module (5).

3. The two-range continuously variable transmission according to claim 1, characterized in that: The first motor (2), the second motor (3), the double planetary gear mechanism (4), the first wet clutch (C1) and the second wet clutch (C2) are arranged inside a gearbox.

4. A vehicle, characterized in that: The vehicle is a tractor, and the vehicle comprises the two-section continuously variable transmission for a tractor according to any one of claims 1 to 3.

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