Clutch assembly based on electromagnet adsorption control

Abstract

According to the clutch assembly based on electromagnet attraction control, a plurality of electromagnets are pre-buried in a large-mass flywheel or a pressing disc, and a plurality of steel plates are arranged on the surface, opposite to the pressing disc, of a driven disc in the circumferential direction. When a driver steps on the clutch pedal, the electromagnet is electrified to generate strong adsorption force, so that the relative sliding of the driven disc and the pressure disc in the separation stage is reduced, and the friction loss and the heat accumulation are obviously reduced. By means of the design, stability and reliability are improved in the clutch separation process, and the service life of the driven disc and related parts is effectively prolonged. After a driver loosens the clutch pedal, the electromagnet is powered off and retracts backwards under the action of the internal reset spring, the diaphragm spring enables the pressure plate to return and be separated from the driven plate, and the system returns to a normal non-adsorption state. The clutch assembly is reasonable in structure, can realize quick control, is suitable for various automobile and mechanical transmission fields, and has positive significance in reducing the maintenance cost and prolonging the service life of the clutch assembly.

Description

Technical field:

[0001] The present invention belongs to the technical field of automobile transmission system, and relates to a clutch assembly that uses electromagnets to implement nonlinear adsorption control in the clutch engagement state and the process of transitioning from separation to engagement. By arranging electromagnets on the pressure plate and arranging corresponding steel plates on the friction plate of the driven plate, the electromagnets generate controllable adsorption force, improve the smoothness of the clutch power transmission process, reduce the relative sliding and wear between the pressure plate and the driven plate, and improve the service life and working quality of the clutch. Background technology:

[0002] As a crucial component in the automotive powertrain, the clutch is mainly responsible for the connection and separation of power between the engine and the gearbox. The traditional clutch system relies on a diaphragm spring or a coil spring mechanism to separate or engage the driven plate and the pressure plate when the driver steps on or releases the clutch pedal. When the clutch is engaged again after being separated, or when the load changes after being engaged for a long time, there is often a certain amount of relative slip between the pressure plate and the driven plate. This slip will cause local high heat and increased wear on the friction plate, thereby shortening the service life of the clutch and affecting the smoothness of the vehicle's shifting and starting.

[0003] In actual driving, when the driver releases the clutch pedal, the clutch transitions from the disengaged state to the engaged state. This process is accompanied by the dynamic behavior of the pressure plate approaching the driven plate and gradually restoring the friction contact. If the engagement speed and method of the pressure plate and the driven plate cannot be effectively controlled at this time, relatively high-speed sliding will occur in an instant, the friction plate will heat up rapidly, and the wear will increase. At the same time, while maintaining normal driving conditions (i.e., no pedal is pressed, and the clutch is engaged stably), load changes, road conditions, or engine output fluctuations can also cause small but frequent relative sliding. These long-term accumulated micro-wear will reduce the overall reliability of the clutch.

[0004] Existing improvements mostly focus on optimizing friction materials (such as high temperature wear-resistant friction plates), strengthening heat dissipation structures or improving diaphragm spring characteristics, but it is difficult to fundamentally solve the problem of relative sliding during the meshing and meshing transition stages. If an auxiliary control force can be applied between the driven plate and the pressure plate during this process to make them fit more smoothly, friction heating and wear will be significantly reduced. This is exactly the goal to be achieved by the present invention. Summary of the invention:

[0005] The innovation of the present invention is to use electromagnetic adsorption force to actively control the clutch engagement process and the tiny relative slip in the engagement state. When the driver releases the clutch pedal and transitions from the disengaged state to the engaged state, a number of electromagnets located on the pressure plate are energized to generate a magnetic field, and correspondingly, a number of steel plates are provided on the surface of the driven plate friction plate. Under the nonlinear control strategy, the electromagnet current gradually increases, and the adsorption force is slowly released according to the set curve, so that the driven plate and the pressure plate are adsorbed and approached in a flexible manner, reducing the relative slip and impact between the two during the engagement process. This kind of flexible linkage is like adding an "invisible gripper" to pure mechanical contact, making the clutch engagement smoother and more stable.

[0006] When the clutch pedal is not pressed, the electromagnet can maintain a moderate current to keep the driven plate and the pressure plate in a closer linkage, thereby reducing intermittent relative slip caused by power fluctuations. In this state, even if the engine torque changes, it will not cause sudden high-speed slipping of the friction plate, greatly reducing the accumulation rate of wear.

[0007] The control strategy of the present invention emphasizes nonlinearity and damping design. Nonlinear control refers to dynamically adjusting the current of the electromagnet according to multiple parameters such as pedal stroke, engine speed, transmission load, temperature, and friction plate state, so that the adsorption force curve does not simply increase linearly, but gradually transitions according to actual needs. This can avoid the sudden generation of huge adsorption force at the moment when the electromagnet is just powered on, causing impact and additional wear. The damping design can add elastic parts or buffer pads to the electromagnet body or its mounting structure to provide a rebound or energy absorption path for mechanical contact when the electromagnet approaches the steel plate surface to prevent hard collision.

[0008] It is worth mentioning that the present invention uniformly installs the electromagnet on the pressure plate side. The advantages of this are:

[0009] The pressure plate is the active control end, and its axial movement is driven by a diaphragm spring or a hydraulic mechanism. The electromagnet is installed at the rear or inner annular area of ​​the pressure plate. There is no need to change the flywheel structure, which simplifies the modification difficulty.

[0010] Electromagnets are distributed on the pressure plate, which can directly control the corresponding driven disc friction plate, thereby establishing a clear force transmission channel and achieving nonlinear regulation more accurately.

[0011] The unified installation position makes it easier to replace the electromagnet assembly or calibrate the control module during later maintenance. Technical principle and working process:

[0012] When the vehicle is driving, it is assumed that the engine has been started and is running stably, and the gearbox is in the appropriate gear. At this time, if the driver has not stepped on the clutch pedal, the clutch is already in the meshing state, and the power of the engine is transmitted through the flywheel-driven plate-pressure plate-gearbox shaft. Usually, this is a mechanical rigid connection, but due to load fluctuations and material elasticity, a small amount of micro-slippage may still exist. At this time, the electromagnet of the present invention is passed with a set small current to generate a certain auxiliary adsorption force, which "gently" pulls the driven plate friction plate toward the pressure plate, more firmly presses the friction interface, reduces micro-slippage, and thus reduces the wear accumulation rate.

[0013] When the driver releases the clutch pedal after starting from neutral or disengaged state or shifting gears, the clutch begins to transition from disengagement to engagement. In traditional clutches, this process inevitably leads to sudden friction intensification. In the present invention, when the control module detects that the clutch pedal is gradually released from the depressed state to a certain travel range, the electromagnet nonlinear control strategy is activated: the electromagnet slowly increases the current to make the adsorption force curve rise smoothly. At the same time, the pressure plate moves toward the driven plate under the help of the diaphragm spring or hydraulic power. When the two are close but not completely close, the electromagnetic adsorption force begins to work, gently pulling the driven plate toward the pressure plate, so that it establishes contact at a lower relative sliding speed, thereby avoiding the instantaneous generation of large friction.

[0014] During this process, if the friction interface temperature is detected to be too high or the engine speed fluctuates violently, the control module can temporarily reduce the electromagnet current to reduce the adsorption force and further optimize the clutch engagement curve. After the entire meshing is completed, the control module maintains the electromagnet current at a moderate level to ensure the low wear characteristics of the clutch in a stable state.

[0015] When the clutch pedal is pressed again to disengage the clutch, the electromagnet current gradually decreases until the power is cut off, the adsorption force disappears, the driven plate and the pressure plate separate normally, and no obstacles are created for the traditional separation action.

[0016] Nonlinear control and damping design details: Nonlinear control is the key technical point of this invention. The control module has a built-in specific algorithm that can calculate and adjust the electromagnet current in real time according to the following input parameters:

[0017] Clutch pedal travel sensor signal: characterizes the dynamic process of separation and engagement. The change rate and amplitude of the pedal travel are important bases for adjusting the speed and upper limit of the electromagnet current increase and decrease.

[0018] Engine speed and torque signal: obtained through engine ECU data or speed sensor. If the engine speed changes too quickly, the electromagnet adsorption force should be increased to buffer the slip; if the temperature is too high or the torque is overloaded, the adsorption force can be reduced to prevent overheating from causing material performance degradation.

[0019] Temperature sensor: monitors the clutch cavity temperature. When the temperature approaches the safety upper limit, the control module reduces the current, relaxes the auxiliary force of the meshing process, and reduces the system heat load.

[0020] Wear status and historical data: The control strategy can be optimized long-term through the friction plate thickness sensor (optional) or periodic maintenance data.

[0021] In terms of damping design, elastic washers or micro damping springs are arranged at the junction of the electromagnet and the pressure plate, or in the sleeve of the electromagnet body. When the electromagnet is energized and close to the surface of the steel plate, these elastic elements can absorb part of the energy to prevent hard impact. The effect of this mechanical buffer is particularly significant within a small distance, which can convert possible hard contact into flexible contact, further reducing the probability of impact on the friction interface.

[0022] Structure and material selection:

[0023] The electromagnetic coil of the present invention is made of highly heat-resistant insulating materials, such as high-temperature resistant enameled wire, to adapt to the working temperature of up to 200°C or even higher in the clutch environment. The shell material can be made of high-strength alloy steel or heat-resistant stainless steel to maintain stability under high-speed rotation and thermal expansion and contraction conditions.

[0024] The steel plate is about 4mm thick and made of high-strength alloy steel. The surface can be rust-proofed and strengthened. The distribution of the steel plates is the same as the number of electromagnets, generally 3 to 6 groups, evenly distributed in the circumferential direction of the friction plate surface of the driven disc, thereby ensuring uniform distribution of adsorption force and reducing eccentric force and vibration.

[0025] The pressure plate is an existing component in the traditional clutch. To install the newly added electromagnet, several mounting holes or grooves need to be processed on its inner circumference to embed the electromagnet assembly. At the same time, corresponding wiring and insulation measures are added to ensure that the current is transmitted from the vehicle power supply through the control module to the electromagnet without external interference.

[0026] Implementation and performance verification:

[0027] A mid-sized sedan was set up for testing: Compared with the traditional clutch, when the driver starts from idle, the process of releasing the clutch pedal is improved under the scheme of the present invention. The traditional scheme often generates more friction heating and shaking at the moment of contact, while the electromagnet of the present invention slowly increases the adsorption force, gently pulling the driven plate toward the pressure plate, significantly reducing instantaneous wear. Measured data shows that after multiple starts, the temperature rise of the friction plate is reduced by about 15%-20% compared with the traditional scheme, and the wear is reduced by about 25%. In long-term tests, the service life of the clutch is extended by about 30%, and the driver feedback shows that the shifting and smoothness are significantly improved.

[0028] The invention also demonstrates its value in re-acceleration under high-speed driving or long-distance driving conditions. When the road slope changes or the engine torque pulsation causes micro-slipping, the electromagnet can be properly energized to reduce the sliding amplitude, thereby reducing the fatigue and loss of the friction plate.

[0029] Feasibility and industrialization prospects:

[0030] The present invention only needs to add several electromagnets and steel plate components, as well as control modules and sensors, and appropriately improve the pressure plate structure on the basis of the traditional clutch. The material and manufacturing process requirements do not exceed the current automotive parts production capacity. With the maturity of automotive electronic control technology and the reduction of costs, the present invention has a good industrialization prospect. Its advantages include:

[0031] Significantly improve clutch durability, reduce replacement frequency and maintenance costs;

[0032] Improve the driving experience, especially the starting and gear shifting smoothness for novice drivers;

[0033] Suitable for various types of vehicles, including passenger cars, commercial vehicles, trucks, buses and special vehicles;

[0034] It can be integrated with other electronic control systems of the vehicle (such as CAN bus, ECU) to further improve the level of intelligence.

[0035] Extensions and variations:

[0036] Without departing from the spirit and basic principles of the present invention, the number of electromagnets, the magnitude of the adsorption force, the control strategy and the damping scheme can be adjusted. For example:

[0037] For heavy-loaded vehicles, the number of electromagnets can be increased, or higher-strength steel plates can be used to achieve stronger adsorption control.

[0038] Use adaptive control algorithms and artificial intelligence or machine learning to continuously optimize nonlinear control models to adapt to different driver habits and road conditions.

[0039] Temperature and strain sensors are integrated into the electromagnet to dynamically monitor and feedback the working status of the electromagnet and friction plate, allowing the control module to distribute current more accurately. Description of the drawings:

[0040] Figure 1 The figure is a schematic diagram (schematic) of a clutch assembly in an embodiment of the present invention. In the figure: 3 to 6 electromagnets (3) are preset along the circumferential direction on the pressure plate (1), and 3 to 6 steel plates (4) are arranged at corresponding positions on the driven plate friction plate (2). An elastic washer (not numbered) can be arranged between the pressure plate (1) and the electromagnet (3) as a damping element, and the control module and the sensor are not drawn in detail in the figure. The actual structure can be changed and optimized according to the vehicle requirements.

[0041] By installing the electromagnet on the pressure plate and arranging a steel plate on the friction plate of the driven plate, the electromagnetic adsorption force is used for nonlinear control and damping buffering when the clutch is in the engaged state and in the critical stage of transition from separation to engagement, which effectively reduces relative slip and friction heat, greatly prolongs the service life of the clutch and improves driving comfort.

[0042] The present invention provides a highly potential improvement path for the traditional clutch, achieving significant performance improvement at a relatively low cost and with moderate structural modification, and has positive significance for the design of future intelligent and durable transmission systems.

Claims

1. A clutch assembly based on electromagnet adsorption control, comprising a pressure plate (1) and a driven plate friction plate (2), characterized in that: A plurality of electromagnets (3) are evenly distributed along the circumferential direction on the inner side of the pressure plate (1), and the electromagnets (3) are powered and regulated by an on-board power supply and a control module; A plurality of steel plates (4) are arranged along the circumferential direction on the surface of the driven disc friction plate (2) opposite to the pressure plate (1), and the positions of the steel plates (4) correspond one to one with the electromagnets (3); When the clutch is in an engaged state (the driver does not step on the clutch pedal) or transitions from a disengaged state to an engaged state (the driver gradually releases the clutch pedal), the electromagnet (3) is energized to generate a controllable adsorption force, so that the relative sliding between the driven disc friction plate (2) and the pressure plate (1) is reduced, thereby reducing friction heat and wear; The output force of the electromagnet (3) is regulated by a nonlinear control module and combined with appropriate damping means to avoid excessive impact during the adsorption process of the electromagnet (3); When the clutch is pressed down again to separate, the electromagnet (3) is powered off or the current is reduced, so that the pressure plate (1) and the driven plate friction plate (2) are separated smoothly without affecting the normal separation process of the clutch.

2. The clutch assembly according to claim 1, characterized in that: The number of the electromagnets (3) is 3 to 6, and the number of the steel plates (4) corresponds to the same number of the electromagnets (3) and is evenly distributed in the circumferential direction.

3. The clutch assembly according to claim 1 or 2, characterized in that: The adsorption force of the electromagnet (3) is designed according to the maximum transmission torque and reserve coefficient of the clutch, and can be adjusted in stages or continuously through the nonlinear control strategy of the control module, so as to gradually release the adsorption force during the clutch engagement or engagement transition stage to avoid instantaneous impact.

4. The clutch assembly according to any one of claims 1 to 3, characterized in that: The control module is connected to a clutch pedal position sensor, an engine speed sensor and a temperature sensor. When the driver releases the clutch pedal, the control module gradually increases the current of the electromagnet (3) according to the pedal travel signal, and maintains a moderate adsorption force after reaching a stable meshing state. When the temperature is too high or the working conditions are harsh, the control module can reduce the current and the adsorption force to prevent overheating or abnormal wear of the friction plate.

5. The clutch assembly according to any one of claims 1 to 4, characterized in that: The electromagnet (3) is made of high temperature resistant insulating material and a high performance coil to ensure good magnetic response and stability under high temperature conditions.

6. The clutch assembly according to any one of claims 1 to 5, characterized in that: The damping means comprises adding a buffer washer or an elastic element to the mounting structure of the electromagnet (3) to provide mechanical buffering when the electromagnet (3) is close to the surface of the steel plate (4) to reduce the impact of actual contact.

7. The clutch assembly according to any one of claims 1 to 6, characterized in that: The steel plate (4) has a thickness of about 4 mm and is made of high-strength steel. The surface treatment may be performed as required to ensure good wear resistance and long service life in the electromagnetic adsorption state.

8. The clutch assembly according to any one of claims 1 to 7, characterized in that: The control module can be built-in with a nonlinear algorithm or a model predictive control strategy to ensure that the adsorption characteristics of the electromagnet (3) under different working conditions (low-speed starting, normal driving, emergency) can be flexibly adjusted, thereby always maintaining the best meshing quality and the lowest wear rate of the clutch system.

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