Control mechanism for electric control gear shifting of hybrid tractor

Abstract

The utility model relates to a control mechanism for electric control gear shifting of a hybrid tractor. The control mechanism comprises a control module, a gear shifting mechanism, an executing mechanism and a control panel. The control module comprises a gear shifting control program, the gear shifting mechanism comprises a meshing sleeve, a gear shifting gear and a transmission shaft, the gear shifting gear is rotationally connected to the transmission shaft, the meshing sleeve is slidably connected to the transmission shaft, and meshing structures are arranged between the meshing sleeve and the transmission shaft and between the meshing sleeve and the gear shifting gear and used for achieving synchronous transmission of the transmission shaft and the gear shifting gear. The executing mechanism is used for controlling the meshing sleeve to axially move on the transmission shaft; the control program is used for selecting a gear shifting gear according to a signal of the control panel, controlling the meshing sleeve to move through the executing mechanism to achieve gear shifting, if meshing is not successful, meshing is executed again after resetting, and if meshing is not completed within preset time, a gear engaging failure signal is sent, and the rotating speed of the speed change mechanism is adjusted till meshing is completed.

Description

TECHNICAL FIELD

[0001] The utility model relates to a control mechanism for electric control gear shifting of hybrid tractor. BACKGROUND

[0002] In the field of modern agricultural machinery, the power of wheeled tractors is continuously increasing, which significantly improves their working range and operating speed. In order to achieve the best match between the power and economy of tractors, the tractors need to be able to automatically select the appropriate gear according to the engine operating conditions and load changes. Currently, high-power tractors abroad generally use electronic control automatic gear shifting technology, such as Deere's 8000 series, Fint's 900 series, etc. These models have realized efficient and accurate gear shifting and improved operating efficiency and driving comfort, thanks to their advanced electronic control systems.

[0003] In contrast, most high-power wheeled tractors developed domestically use a main clutch plus a mechanical gear shifting transmission box, or a wet type main clutch plus a power gear shifting transmission box. These transmission boxes usually use a mechanical double lever control method, which has the advantages of strong carrying capacity, multiple gears, and wide speed ratio range, and is suitable for various operating requirements. However, in some complex operating conditions, mechanical gear shifting operation can easily lead to misshifting, thereby affecting the driving safety of the tractor. In addition, if the driver cannot accurately grasp the gear shifting timing, it will affect the fuel economy and power performance of the tractor, resulting in reduced operating efficiency. At the same time, frequent manual gear shifting also increases the labor intensity of the driver and affects the comfort of long-time operation. Therefore, the existing mechanical gear shifting method still has a lot of room for improvement in terms of accurate gear shifting, driving convenience, and fuel economy. UTILITY MODEL CONTENTS

[0004] The utility model aims at solving the above technical deficiencies and provides a control mechanism for electric control gear shifting of hybrid tractor.

[0005] A control mechanism for electric control gear shifting of hybrid tractor, comprising a control module, a gear shifting mechanism, an execution mechanism, and a control panel. The control module includes a gear shifting control program. The gear shifting mechanism includes a meshing sleeve, a gear shifting gear, and a transmission shaft. The gear shifting gear is rotationally connected to the transmission shaft, and the meshing sleeve is slidingly connected to the transmission shaft. A meshing structure is provided between the meshing sleeve, the transmission shaft, and the gear shifting gear. The meshing sleeve is used to realize synchronous transmission of the transmission shaft and the gear shifting gear. The execution mechanism is used to control the axial movement of the meshing sleeve on the transmission shaft.

[0006] The control program is used to perform the following steps:

[0007] Step 1: Select the gear shifting gear that needs to be engaged according to the signal transmitted by the control panel.

[0008] Step two: the engagement sleeve is moved by the actuator to synchronize the transmission shaft and the corresponding shift gear;

[0009] Step three: if the engagement is not successful, the engagement sleeve is reset by the actuator, and the engagement action is re-executed, and the above process is repeated until the engagement sleeve is engaged with the shift gear;

[0010] Step four: if the engagement is not completed within the preset time, a gear engagement failure signal is sent, the speed of the transmission mechanism is adjusted, steps three and four are repeated until the engagement sleeve is engaged with the shift gear.

[0011] Further, the engagement sleeve, the transmission shaft and the shift gear are engaged through a spline structure.

[0012] Further, the actuator includes a motor, a rocker arm, a shift fork shaft, a shift fork foot and a shift fork sleeve, the motor is connected to one end of the rocker arm, the other end of the rocker arm is connected to the shift fork sleeve, the shift fork sleeve is slidably connected to the shift fork shaft, and the outer side of the shift fork sleeve is provided with a pair of shift fork feet connected to the engagement sleeve.

[0013] Further, a displacement sensor is arranged in the actuator.

[0014] Further, a bearing is arranged between the shift gear and the transmission shaft.

[0015] Further, the control module includes a controller, and the controller includes:

[0016] Vehicle control unit (VCU): receiving operation signals and forwarding them to the TCU;

[0017] Transmission control unit (TCU): according to the instruction signal from the VCU, combining the feedback of the position sensor, controlling the forward and reverse rotation of the motor, so as to realize the shift of the gear;

[0018] Speed control unit (RCU): in the case of incomplete gear engagement, the RCU receives the signal sent by the TCU to adjust the speed of the transmission mechanism.

[0019] Further, the control module further includes a display screen, and the display screen is used to display the gear shifting state information.

[0020] Advantages: compared with the prior art, the utility model has the following advantages:

[0021] The gear shifting control program of the utility model is based on the cooperative work of VCU (vehicle control unit), TCU (transmission control unit) and RCU (speed control unit), and full-automatic control of gear shifting is realized. The driver only needs to press the gear shifting button, and the system can automatically perform the gear shifting operation without manual intervention, which greatly improves the convenience and work efficiency of gear shifting.

[0022] The shift control program can monitor the shift state in real time and accurately control the forward / reverse rotation of the shift motor based on the feedback from the motor position sensor, ensuring the synchronized action of the shift lever, shift fork, and engagement sleeve. If the shift fails, the system will automatically reset and retry the shift, avoiding the problem of shift jam caused by mismatched engagement.

[0023] After the shift fails, the shift control program sends a signal to the RCU (Rotary Control Unit) to adjust the speed of the transmission mechanism, making the gear set rotate to a new angle to optimize the engagement conditions. Then, the system automatically re-executes the shift operation, which can continue until the shift is successful, effectively improving the success rate of the shift.

[0024] The program automatically performs the neutral detection before ignition and after engine shutdown. If the gear is not in neutral, the system will immediately perform the neutral reset operation to ensure the tractor is in a safe state when starting or shutting down, preventing accidental movement of the vehicle caused by misoperation and improving safety.

[0025] The shift control program uses CAN bus architecture, and the TCU can obtain shift instructions in real time and interact with shift motor, position sensor, display screen and other modules to ensure accurate and efficient shift operation. In addition, the shift state can be displayed in real time on the display screen, allowing the driver to intuitively monitor the current gear state and improve the visualization of the operation.

[0026] The shift control program can dynamically adjust the shift execution strategy based on current gear, target gear, gear set speed, shift motor position and other parameters. For example, in low-speed or high-load working conditions, the program can optimize the shift timing to avoid shift impact, improve shift smoothness, and improve the driving experience and power transmission efficiency of the vehicle.

[0027] Compared with traditional mechanical shift, the shift control program reduces the impact and friction between gears by precisely controlling the engagement process, reduces the mechanical wear of the shift mechanism, and prolongs the service life of the equipment. At the same time, the system can monitor the shift motor and engagement state in real time, provide early warning of potential faults, and reduce maintenance costs.

[0028] The shift control program can adapt to different tractor transmission structures and support multiple shift modes (manual shift, automatic shift, etc.), which can be adjusted according to different work requirements to improve the flexibility and adaptability of the system. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a flowchart of the shift control program. DETAILED DESCRIPTION

[0030] In order to deepen the understanding of the utility model, the utility model will be further described in combination with embodiments and drawings below, and the embodiments are only used to explain the utility model and do not constitute the limitation on the protection scope of the utility model.

[0031] A kind of control mechanism of hybrid tractor electric control gear shifting, including control module, gear shifting mechanism, actuating mechanism, control panel.Control module includes gear shifting control program, gear shifting mechanism includes engagement sleeve, gear shifting gear, transmission shaft, gear shifting gear is rotatably connected on transmission shaft, engagement sleeve is slidably connected on transmission shaft, engagement sleeve is equipped with engagement structure between transmission shaft and gear shifting gear, engagement sleeve is used to realize synchronous transmission of transmission shaft and gear shifting gear, actuating mechanism is used to control engagement sleeve and moves on transmission shaft axial.

[0032] In this embodiment, control module receives signals from control panel, and executes gear shifting control program.Firstly, the system determines target gear shifting gear according to received gear shifting instruction.Then, actuating mechanism drives engagement sleeve to move along transmission shaft axial, so that engagement sleeve and target gear shifting gear complete engagement, and then realize synchronous motion of transmission shaft and gear shifting gear.If engagement fails, actuating mechanism will automatically control engagement sleeve to reset, and repeat engagement action until successful engagement.If still unsuccessful within preset time, control module sends gear hanging failure signal, and adjusts the speed of speed change mechanism to optimize gear engagement conditions, and tries to engage again until successful.

[0033] This embodiment realizes automatic gear shifting of tractor by electric control gear shifting mode, avoids gear impact and engagement problems that may occur in traditional mechanical gear shifting process, improves gear shifting stability and reliability.In addition, the control mechanism can automatically adjust the speed of speed change mechanism when gear shifting fails, improve gear shifting success rate, reduce human intervention, improve driving comfort and work efficiency.

[0034] In other embodiments, gear shifting control program can use different algorithms to optimize gear shifting logic, for example, introduce adaptive gear shifting strategy, automatically adjust gear shifting timing according to engine load and working environment.In addition, actuating mechanism can use hydraulic drive structure to replace motor drive scheme to adapt to gear shifting system with larger torque demand.

[0035] In a possible embodiment, the engagement sleeve, transmission shaft and gear shifting gear are engaged through spline structure.

[0036] Spline structure improves engagement accuracy and stability, so that engagement sleeve can reliably slide along transmission shaft, and form stable torque transmission path at gear shifting gear.Through the design of precision machined spline, gear slippage and vibration that may occur during gear shifting can be effectively reduced, and the stability of power transmission is improved.

[0037] The spline structure makes the engagement more reliable, reduces the wear between gears, improves the smoothness of shifting, and prolongs the service life of the shifting mechanism. In addition, this structure can maintain good transmission efficiency under high load conditions, improving the vehicle's power performance.

[0038] In other embodiments, the spline structure can adopt various shapes such as straight spline, involute spline or circular spline to adapt to different shifting load requirements. At the same time, wedge coupling or other high-precision positioning structures can be used to replace the spline connection to improve the rigidity and service life of the system.

[0039] In one possible embodiment, the actuator includes a motor, a rocker arm, a shift fork shaft, a shift fork foot, and a shift fork sleeve. The motor is connected to one end of the rocker arm, the other end of the rocker arm is connected to the shift fork sleeve, the shift fork sleeve is slidingly sleeved on the shift fork shaft, and the outer side of the shift fork sleeve is provided with a shift fork foot connected to the engagement sleeve.

[0040] When the shifting command is issued, the control module sends a signal to the actuator, the motor drives the rocker arm to move, the rocker arm drives the shift fork sleeve to slide along the shift fork shaft, the shift fork foot pushes the engagement sleeve to move axially along the transmission shaft, and finally the engagement of the target gear is achieved. If the engagement fails, the motor will control the rocker arm to return to its original position and re-execute the shifting action.

[0041] The actuator has a compact structure and clear transmission path. Through motor drive and lever mechanism amplification, it can realize fast and stable shifting. Compared with traditional mechanical shifting, this mechanism can reduce human operation errors, improve the automation level and execution precision of shifting.

[0042] In other embodiments, the rocker arm can be of different lengths or shapes to optimize the efficiency of shifting torque transmission. At the same time, the shift fork structure can be replaced by a linear drive mechanism to improve the shifting accuracy. In addition, a hydraulic actuator can be used to meet the higher load shifting requirements.

[0043] In one possible embodiment, a displacement sensor is provided in the actuator.

[0044] Working principle

[0045] The displacement sensor is used to detect the position of the shift fork shaft or the shift fork sleeve in real time and feed back the data to the control module. The control module judges the engagement state according to the feedback information and adjusts the motor control strategy when the engagement is not complete to optimize the shifting execution process.

[0046] By introducing the displacement sensor, the shifting execution can be monitored in real time, the shifting accuracy and reliability can be improved, the engagement sleeve can be prevented from being stuck or failing to shift, and the intelligent level of the vehicle can be further improved.

[0047] In other embodiments, the displacement sensor can employ different detection technologies, such as photoelectric sensors, Hall sensors, or LVDT sensors, to improve detection accuracy and adaptability. At the same time, a force sensor can be used to detect the engagement torque to assist in shift control.

[0048] In one possible embodiment, a bearing is provided between the shift gear and the transmission shaft.

[0049] The bearing is used to reduce the rotational friction of the shift gear on the transmission shaft, ensuring that the shift gear can rotate freely under low resistance to achieve smoother power transmission.

[0050] Using a bearing reduces friction between the shift gear and the transmission shaft, improves the smoothness of shifting, and reduces wear, improving the reliability and durability of the transmission mechanism.

[0051] In other embodiments, ball bearings, needle bearings, or sliding bearings can be selected to meet the shifting requirements of different load conditions.

[0052] In one possible embodiment, the control module includes a controller, which includes a vehicle control unit (VCU), a transmission control unit (TCU), and a rotational speed control unit (RCU).

[0053] The VCU receives operation signals and forwards them to the TCU, which controls the shift actuator according to the instructions of the VCU, while combining the feedback of the displacement sensor to optimize the shift action. When the shift fails, the RCU receives the TCU signal and adjusts the rotational speed of the transmission mechanism to optimize the engagement conditions.

[0054] This control system improves the intelligence and automation level of shifting, reduces human intervention, and improves the success rate of shifting and driving comfort.

[0055] In one possible embodiment, the control module further includes a display screen for displaying shift status information.

[0056] The display screen provides intuitive feedback on the shift status, improving the user's perception of the vehicle's status and facilitating maintenance and fault diagnosis.

[0057] Working process: The operator sends a shift signal through the gear mode selection button on the control panel. This signal is first transmitted to the vehicle control unit (VCU). The VCU sends corresponding shift instructions to the transmission control unit (TCU) based on the current operating conditions. After receiving the instructions, the TCU combines the feedback information from the position sensor inside the shift motor and controls the forward / reverse rotation of the shift motor through the H-bridge circuit.

[0058] After the shift motor rotates, it drives the shift lever to adjust its position. At the same time, the shift lever drives the shift fork through the shift fork shaft, and finally pushes the engagement sleeve along the transmission shaft to mesh with the 1 / 2 gear set of the target gear, completing the gear shift.

[0059] Before ignition or after extinguishing, the VCU will automatically send a neutral command to the TCU. If the current gear is not in the neutral state, the TCU will control the shift mechanism according to the command to automatically return the gear to the neutral position. At this time, the gear information will be displayed in real time on the display screen, ensuring that the driver can intuitively obtain the current shift state.

[0060] When the tractor needs to shift during operation, the driver presses the shift button, and the shift command is transmitted to the VCU. The VCU combines the current working conditions and sends the shift command to the TCU again. After receiving the signal, the TCU controls the H-bridge circuit output signal by reading the feedback information of the shift motor position sensor, driving the shift motor to rotate forward or reverse.

[0061] After the motor rotates, the shift lever moves to the target position, and the adjustment of this position depends on the target gear pressed and the current gear. The real-time position information of the shift lever will be displayed on the diagnostic page of the display screen, making it easy for the operator to monitor the shift execution status.

[0062] During the shift process, the motor moves the shift lever, which further drives the shift fork through the shift fork shaft, causing the shift fork to push the engagement sleeve and mesh with the target gear set. Since the gear set is always rotating after the engine starts, once the engagement sleeve successfully meshes, power transmission is achieved, and the gear is engaged.

[0063] The success of the shift is closely related to the rotational speed of the gear set at idle speed. To ensure smooth shifting, the rotational speed needs to be adjusted to an appropriate range so that the shift lever can smoothly push the engagement sleeve into the target position. The driver can preliminarily judge the gear engagement status through the shift lever position information on the display screen, but the final success of the gear engagement should be based on the gear information on the display screen home page.

[0064] If the gear engagement fails, the TCU will control the shift motor to automatically return the shift lever to the zero position and perform the reciprocating movement + zero return action within a limited time to attempt the gear engagement multiple times. If it still fails within the set time, the TCU will send a gear engagement failure signal to the VCU.

[0065] When the VCU receives the gear engagement failure signal, it will further transmit the signal to the rotational speed control unit (RCU). After receiving the signal, the RCU adjusts the rotational speed of the transmission mechanism, causing the gear set to rotate to a new angle to optimize the meshing conditions. After the adjustment is complete, the VCU will send a shift command to the TCU again, and the TCU will attempt to control the motor to rotate and drive the shift mechanism. This process will continue until the shift is successful.

[0066] The whole shift control system adopts CAN bus structure, compared with the traditional independent signal line connection mode, the number of wiring is greatly reduced, and the reliability of the system is improved.

[0067] In addition, the controller, the shift mechanism, the display screen and the like transmit data through the bus, not only the data interaction ability is enhanced, also the collaborative work between each component is more orderly, ensures the intelligentization and automation of the shift operation, improves the overall shift efficiency and driving experience.

[0068] The above only describes the preferred embodiments of the present application, and is not used to limit the present application, any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A control mechanism for electrically controlling gear shifting of a hybrid tractor, characterized by, Including control module, shift mechanism, actuator, control panel, the control module includes shift control program, the shift mechanism includes engagement sleeve, shift gear, transmission shaft, shift gear rotationally connected on transmission shaft, engagement sleeve slidingly connected on transmission shaft, engagement sleeve and transmission shaft, shift gear between being equipped with engagement structure, engagement sleeve is used for realizing transmission shaft and shift gear synchronous transmission, actuator is used for controlling engagement sleeve axial movement on transmission shaft.

2. The control mechanism for electrically controlling gear shifting of a hybrid tractor according to claim 1, wherein The engagement sleeve, transmission shaft and shift gear are engaged through spline structure.

3. The control mechanism for electrically controlling gear shifting of a hybrid tractor according to claim 1, wherein The actuator includes motor, rocker, fork shaft, fork foot and fork sleeve, the motor is connected with one end of the rocker, the other end of the rocker is connected with the fork sleeve, the fork sleeve is slidingly sleeved on the fork shaft, and the outer side of the fork sleeve is provided with a pair of fork feet connected with the engagement sleeve.

4. The control mechanism for electrically controlling gear shifting of a hybrid tractor according to claim 3, wherein The actuator is provided with a displacement sensor.

5. The control mechanism for electrically controlled gear shifting of a hybrid tractor according to claim 1, wherein The shift gear and the transmission shaft are provided with a bearing.

6. The control mechanism for electrically controlled gear shifting of a hybrid tractor according to claim 4, wherein The control module includes a controller, and the controller includes: Vehicle control unit (VCU): receiving operation signal and forwarding it to TCU; Transmission control unit (TCU): according to the instruction signal from VCU, combined with the feedback of position sensor, control the forward and reverse rotation of motor, so as to realize the shift of gear; Speed control unit (RCU): in the case of not completing the gear, RCU will receive the signal sent by TCU, adjust the speed of transmission mechanism.

7. The control mechanism for electrically controlled gear shifting of a hybrid tractor according to claim 1, wherein The control module further includes a display screen, and the display screen is used to display the shift state information.

Images