Vehicle with auxiliary axle

Abstract

The invention relates to a vehicle (1) with a main drive axle (2) and an auxiliary axle (3), comprising: a multi-plate clutch (6, 12) arranged at least between a wheel hub (4) and a cardan shaft (5, 11), the multi-plate clutch (6, 12) being oil-lubricated and cooled, the multi-plate clutch (6, 12) being designed for coupling and decoupling the auxiliary axle (3) such that, in the decoupled state, the cardan shaft (5, 11), the transmission (7) and / or the electric machine (8) for the auxiliary axle (3) are deactivated, the multi-plate clutch (6, 12) being operated in the decoupled state in a slip mode such that no torque is transmitted via the multi-plate clutch (6, 12).

Description

Technical Field

[0001] The technical field of this invention describes a vehicle having a main axle and an auxiliary axle. Background Technology

[0002] Existing technologies include a variety of techniques and solutions for controlling drive axles and clutch systems in vehicles. Torque distributors, differential systems, and clutches, which enable torque distribution and efficiency improvements, are specifically described here.

[0003] DE 11 2013 005 384 T5 describes an electric drive module for an electric vehicle, comprising a power motor, a reduction gear unit, a differential unit for connecting the axle and the wheels, and a separation mechanism that selectively couples or decouples the reduction gear unit from the differential unit to prevent torque transients and torque reversal.

[0004] DE 10 2021 132 368 A1 describes a wheel release clutch including a housing, an axially movable clutch sleeve with teeth for connecting a hub and a half-shaft, and a drive ring for moving the clutch sleeve between an engaged position and a disengaged position.

[0005] CN105172573A describes a control system, a control method, and a vehicle with an all-wheel hybrid drive system. The drive system includes a front axle unit with a front motor, an internal combustion engine, and a front axle transmission, and a rear axle unit with a rear motor. Summary of the Invention

[0006] The purpose of this invention is to provide a vehicle having a main drive axle and an auxiliary axle, and a method for vehicle control that enables efficient torque transmission and regulation.

[0007] This invention relates to a vehicle having a main drive axle and an auxiliary axle, wherein at least one plate clutch is arranged on the auxiliary axle between a wheel hub and a universal joint. This corresponding plate clutch is oil-lubricated and cooled, and is designed to couple or decouple the auxiliary axle from the corresponding wheel hub. When the auxiliary axle is decoupled from the corresponding wheel hubs on both sides, the auxiliary axle is in a decoupled state, thereby stopping the universal joint, the transmission, and / or the motor of the auxiliary axle, wherein the universal joint is mechanically connected to the transmission and / or the motor. Therefore, in the decoupled state, the plate clutch operates in a slip / slip (Schlupf) manner, thereby not transmitting torque through the plate clutch.

[0008] The main drive axle, such as the rear axle, refers to the primary drive axle of a vehicle, providing most of the driving force and driven by the main drive unit (e.g., an electric motor). The auxiliary axle, such as the front axle, is an additional drive axle that is activated under specific operating conditions, such as to support traction or to enhance performance, wherein the auxiliary axle is driven by a second drive unit (e.g., a second electric motor). A plate clutch is a mechanical component that transmits or interrupts torque between rotating elements, characterized by having multiple friction surfaces, i.e., friction plates. These friction plates are alternately connected to the drive side and the input side, thus, by activating the plate clutch, i.e., by coupling the auxiliary axle to the corresponding hub or wheel associated with that hub, a controlled force lock (Kraftschluss) is generated. This force lock is transmitted via oil located between the two friction surfaces of the plate clutch, for example, in the form of a turbine or fan. The advantage of using oil lubrication in a plate clutch is that force transmission occurs through oil without physical contact, and therefore the friction plates do not wear or only wear slightly.

[0009] Oil lubrication refers to the use of a special lubricant, such as transmission fluid or engine oil, injected between the friction plates to provide force transmission. In addition, oil also acts as a heat carrier, dissipating the heat generated during the operation of the plate clutch.

[0010] Cooling of a plate clutch can be active or passive, aiming to maintain the internal temperature of the clutch at an optimal level. Active cooling is achieved by circulating lubricating oil via an oil pump. During this process, the oil is guided through external or internal cooling circuits, where it transfers heat to the cooling system. In the case of passive cooling, heat is dissipated through natural convection or through the surface of the plate clutch housing equipped with cooling elements.

[0011] Slip-operation means that a plate clutch allows relative movement between the connected components, thus preventing force lock-in.

[0012] The advantage of this invention is improved vehicle efficiency because the auxiliary axle does not consume unnecessary energy in the decoupled state, as the universal joint and transmission do not need to move accordingly. Furthermore, slip adjustment prevents overload of the plate clutch.

[0013] Advantageously, in addition to a first plate clutch located on one side of the auxiliary axle between the wheel hub and the universal joint, a second plate clutch can be located on the opposite side of the auxiliary axle between the second wheel hub and the second universal joint. This second plate clutch is disengageable, causing the universal joint, transmission, and / or motor to stop in the disengaged state.

[0014] Advantageously, the plate clutch can be integrated into a closed housing that allows lubricating oil to circulate for cooling and lubrication of the friction plates.

[0015] A sealed housing refers to a structure that completely surrounds a plate clutch, creating a controlled environment for lubrication and cooling, and sealing it against external influences such as dust, dirt, or water. This sealed housing ensures a controlled environment in which lubricating oil can be effectively distributed and the temperature maintained constant.

[0016] This ensures efficient heat dissipation and lubrication, thereby improving the performance and durability of the plate clutch.

[0017] Advantageously, the plate clutch can be designed to compensate for the speed difference between the wheels of the auxiliary axle, thereby replacing the function of the torque distributor and / or differential.

[0018] A torque distributor is a device that variably distributes torque between the wheels or axles of a vehicle. A differential allows for speed differences between wheels, especially during cornering. Speed ​​differences between the wheels of an auxiliary axle are compensated for in several ways by a plate clutch. One possibility is to operate the plate clutch in a controlled slip manner, where the friction surfaces allow limited relative movement between the drive sides. This allows the wheels to reach different speeds, for example, during cornering, without the need for a mechanical differential. Furthermore, the clamping force acting on the friction plates can be dynamically adapted to load conditions. Here, the clamping force is changed via hydraulic or electric actuators, achieving higher slip at lower clamping forces, which is particularly advantageous in sharp corners or situations with varying ground traction. Moreover, the adjustment of the plate clutch can be adaptively performed by an electronic control unit that analyzes vehicle state parameters such as vehicle speed, wheel speed, and steering angle. Based on this, real-time control of the plate clutch slip ensures optimal torque distribution, thus completely replacing the function of a torque distributor or differential.

[0019] This eliminates the need for additional mechanical components, thus reducing vehicle weight and complexity.

[0020] Advantageously, the control of the plate clutch can be performed by an electronic control unit that takes into account parameters such as wheel speed, vehicle speed and / or driving mode.

[0021] The electronic control unit is a system that processes sensor information and sends control commands to actuators to regulate vehicle functions.

[0022] Therefore, the control of the plate clutch can be flexibly adapted to the vehicle's operating conditions, thereby optimizing efficiency and functionality.

[0023] Advantageously, the control of the plate clutch can be performed in such a way that the decoupling of the auxiliary axle is performed automatically under certain operating conditions, such as in a low power demand mode, where the vehicle is driven only by the main drive axle.

[0024] Low power demand mode refers to the operating state of a vehicle with only the minimum energy requirement, such as when driving downhill or idling.

[0025] This further reduces the vehicle's energy consumption, thereby increasing its driving range.

[0026] Advantageously, the plate clutch can also be equipped with a temperature sensor for detecting the internal temperature of the plate clutch, wherein the plate clutch is adjusted in such a way that once the temperature exceeds a threshold, the plate clutch is switched to slip operation mode to avoid overheating.

[0027] A temperature sensor is a component that measures system temperature and transmits this information to the control unit. Plate clutches with temperature sensors are designed to avoid overheating by adapting their operating mode to thermal conditions. The temperature sensor is positioned directly near the friction plates or within the clutch housing and continuously measures the temperature. This temperature data is transmitted to the electronic control unit (ECU), which analyzes the data in real time. When the detected temperature exceeds a predefined threshold, the control unit triggers adjustment of the plate clutch. In this case, the clamping force on the friction plates is reduced via hydraulic or electric actuators, causing the plate clutch to switch to slip mode. This mode allows the friction plates to slide relative to each other without full force engagement, significantly reducing heat generated by friction. Simultaneously, this operating state aids in heat dissipation because the lubricating oil surrounding the friction plates efficiently carries away excess heat. This adjustment mechanism allows the clutch function to dynamically adapt to thermal conditions without significantly limiting vehicle functionality. Once the temperature drops below the threshold, the plate clutch automatically switches back to normal operating mode. In this way, overheating that could damage the lifespan or reduce the performance of the plate clutch is avoided. This prevents the plate clutch from overheating, thus ensuring the safety and durability of the system.

[0028] It should be understood that the features described above and below can be used not only in the combination described accordingly, but also in other combinations or individually without departing from the framework of the present invention. Attached Figure Description

[0029] The present invention is schematically illustrated in the accompanying drawings by way of embodiments according to the invention, and will be further described with reference to the drawings. Hereinafter shown:

[0030] Figure 1 A schematic diagram of a vehicle according to an embodiment of the present invention is shown.

[0031] List of reference numerals in the attached diagram:

[0032] 1 vehicle

[0033] 2 Main drive axle

[0034] 3 Auxiliary axles

[0035] 4-wheel hub

[0036] 5. First universal joint

[0037] 6 First-plate clutch

[0038] 7. Transmission

[0039] 8 motors

[0040] 9 Revolvers

[0041] 10 Right Wheel

[0042] 11 Second universal joint

[0043] 12 Second-plate clutch

[0044] 13 Electronic Control Unit Detailed Implementation

[0045] Figure 1 A schematic diagram of a vehicle 1 having a main drive axle 2 and an auxiliary axle 3 is shown. The auxiliary axle 3 includes a first plate clutch 6 disposed between the wheel hub 4 of the left wheel 9 and a universal joint 5. The first plate clutch 6 is oil-lubricated and cooled and is designed to couple or decouple the universal joint 5 of the auxiliary axle 3 from the wheel hub 4.

[0046] The left wheel 9 is connected to the transmission 7 via the first plate clutch 6 and the first universal joint 5. The plate clutch 6 enables the transmission of torque from the auxiliary axle 3.

[0047] On the right side, the right wheel 10 is connected to the transmission 7 via a second universal joint 11 and a second-plate clutch 12 disposed between the right wheel 10 and the second universal joint 11. This second-plate clutch 12 is also oil-lubricated and cooled, and is designed to couple or decouple the universal joint 11 of the auxiliary axle 3 from the wheel hub 4 of the right wheel 10. When both the first-plate clutch 6 and the second-plate clutch 12 are disengaged, the first universal joint 5, the second universal joint 11, the transmission 7, and the motor 8 cease operation, thereby reducing energy consumption.

[0048] The transmission 7 is centrally located and transmits the driving force of the motor 8 to the universal joints 5 and 11 of the auxiliary axle 3.

[0049] The configuration shown further illustrates that the plate clutches 6 and 12 are designed to compensate for the speed difference between the wheels 9 and 10 of the auxiliary axle 3, thereby replacing the function of the torque distributor or differential. Furthermore, the control of the plate clutches 6 and 12 can be achieved through an electronic control unit 13, which takes into account parameters such as vehicle speed, wheel speed, and driving mode.

Claims

1. A vehicle (1) having a main drive axle (2) and an auxiliary axle (3), the vehicle comprising: At least one plate clutch (6, 12) is disposed between the hub (4) of the auxiliary axle (3) and the universal joint (5, 11), wherein the at least one plate clutch (6, 12) is oil-lubricated and cooled, wherein the at least one plate clutch (6, 12) is designed to couple or decouple the universal joint (5, 11) of the auxiliary axle (3) from the hub (4), wherein when the at least one plate clutch (6, 12) decouples the universal joint (5, 11) of the auxiliary axle (3) from the hub (4), the universal joint (5, 11), the transmission (7) and / or the motor (8) of the auxiliary axle (3) cease to operate, wherein the universal joint (5, 11) is mechanically connected to the transmission (7) and / or to the motor (8), wherein the at least one plate clutch (6, 12) operates in a slipping manner in the decoupled state, such that torque is not transmitted through the at least one plate clutch (6, 12).

2. The vehicle (1) according to claim 1, characterized in that, The plate clutches (6, 12) are integrated into a closed housing that allows lubricating oil to circulate for cooling and lubrication of the friction plates.

3. The vehicle (1) according to any one of the preceding claims, characterized in that, The plate clutches (6, 12) are designed to compensate for the speed difference between the wheels (9, 10) of the auxiliary axle (3) when engaged, thereby replacing the function of the torque distributor and / or differential.

4. The vehicle (1) according to any one of the preceding claims, characterized in that, The control of the plate clutches (6, 12) is performed by an electronic control unit (13) that takes into account parameters such as wheel speed, vehicle speed and / or driving mode.

5. The vehicle (1) according to claim 4, characterized in that, The control settings for the plate clutches (6, 12) are configured such that, under certain operating conditions, such as in a low power demand mode, the auxiliary axle (3) is automatically decoupled, wherein the drive of the vehicle (1) is accomplished solely by the main drive axle (2).

6. The vehicle (1) according to any one of the preceding claims, characterized in that, The plate clutches (6, 12) are also equipped with a temperature sensor that detects the internal temperature of the plate clutches (6, 12) and adjusts the plate clutches (6, 12) in such a way that if the temperature exceeds a threshold, the plate clutches (6, 12) are switched to slip operation to avoid overheating.

7. A method for controlling a vehicle (1) according to any one of claims 1 to 6, comprising the following steps: The driving status parameters, including wheel speed, vehicle speed and / or driving mode, are detected; the detected parameters are analyzed in the electronic control unit (13); and the plate clutches (6, 12) of the auxiliary axle (3) are automatically engaged or disengaged based on the analyzed parameters.

8. The method according to claim 7, characterized in that, The plate clutches (6, 12) operate in a slipping manner during the decoupled state, so that torque is not transmitted through the plate clutches (6, 12).

9. The method according to claim 7 or 8, characterized in that, When the temperature in the disc clutches (6, 12) exceeds a predetermined threshold, the electronic control unit (13) disengages the disc clutches (6, 12) to prevent further heating.

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