An automatic gear shifting control method under an agricultural machine operation mode

Abstract

This invention provides an automatic gear shifting control method for agricultural machinery in operation mode. The cab includes: a "gear shift lever" for selecting forward, neutral, and reverse driving modes; a "high / low gear switch" for selecting high and low gears; an "accelerator pedal" and a "hand throttle lever" for the driver to control vehicle speed and meet power requirements. The "hand throttle lever" is used for engine speed control during field operations, preventing speed fluctuations caused by the driver's inability to maintain a stable accelerator pedal opening for extended periods. In tractor field operation mode, the method utilizes the "hand throttle lever" signal as one of the reference signals for the automatic transmission's gear shifting control strategy and incorporates a "gear hold" mode and exit mechanism to ensure the automatic transmission shifts gears appropriately according to the driver's intentions to meet operational needs. This maintains an ideal gear position based on operational requirements, ensuring stable operating speed.

Description

Technical Field

[0001] This invention belongs to the field of agricultural machinery transmission technology, specifically relating to an automatic gear shifting control method in agricultural machinery operation mode. Background Technology

[0002] Tractors can undertake tasks such as transportation and traction in agricultural production activities. As the number of agricultural implements that can be assembled increases, the types of operations that can be completed gradually increase, greatly improving agricultural production efficiency.

[0003] Currently, the vast majority of tractors in my country are equipped with manual transmissions. Their inherent structure leads to complex shifting operations and a high degree of reliance on driver skill, severely impacting the quality and efficiency of tractor operation. By adding a control system and gear-shifting actuators, they can be converted into an electromechanical automatic transmission (AMT), automating the gear-shifting process. Due to its advantages such as high transmission efficiency, reliable operation, low cost, and good production continuity, it is an ideal solution for automating agricultural machinery.

[0004] Tractors, when combined with different agricultural implements, can perform operations such as deep plowing, rotary tilling, fertilizing, sowing, and harvesting in the fields. The diversity of their operating conditions, the randomness of their working environment, and the complexity of their operating states mean that tractor shifting strategies differ somewhat from those of automobiles. Therefore, automobile shifting strategies cannot be directly applied to the automatic shifting of tractors. Summary of the Invention

[0005] This invention addresses the need for strict speed control within a range when tractors are performing field operations to ensure work quality. It proposes an automatic gear shifting control method for agricultural machinery operation modes, which maintains an ideal gear according to operational requirements, thereby ensuring stable operating speed.

[0006] To achieve the above-mentioned technical features, the objective of this invention is as follows: an automatic gear shifting control method in an agricultural machinery operation mode, wherein the cab is equipped with: The gear lever is used to select the driving mode: forward, neutral, and reverse. The "high / low range switch" is used to select between high and low ranges. The accelerator pedal and throttle lever are used by the driver to control the vehicle speed and meet the vehicle's power requirements. The "hand throttle push lever" is used for engine speed control during field operations to prevent vehicle speed fluctuations caused by the driver's inability to maintain a fixed opening of the "accelerator pedal" for an extended period of time. In the tractor-operated field mode, the method uses the "hand throttle push lever" signal as one of the reference signals for the automatic transmission shift control strategy, and designs a "gear hold" mode and exit mechanism to ensure that the automatic transmission gears switch reasonably according to the driver's intentions to meet the operational needs.

[0007] The specific steps of the method are as follows: Step 1, Begin; Step 2, System self-check; Step 3: Start the engine and prepare for driving; Step 4: Determine if the gear shift lever is in neutral; if yes, the clutch disengages and power is interrupted, and continue to determine if the gear shift lever is in neutral; if no, proceed to step 5. Step 5, start the vehicle; Step 6: Determine if the "accelerator pedal" signal is greater than the "hand throttle lever" signal; if so, implement automatic gear shifting according to the system strategy, and continue to determine if the "accelerator pedal" signal is greater than the "hand throttle lever" signal; if not, proceed to Step 7. Step 7, implement "gear hold" mode; Step 8: Determine if the engine speed is less than the set value; if not, return to step 6; if yes, proceed to step 9. Step 9: Disengage the clutch, allow the engine to idle, prompt the driver to manually intervene and select the target low gear based on the vehicle speed in real time; then return to step 4.

[0008] The specific method of step 6 is as follows: The driver starts the engine as usual, operates the "gear lever" to select the forward or reverse mode of the vehicle, and after starting, performs normal automatic gear shifting operation according to the set gear shifting strategy through the "accelerator pedal" opening signal and the current "vehicle speed" until the ideal gear and vehicle speed suitable for this operation are obtained.

[0009] In step 6, when the driver manipulates the "hand throttle lever" to output an engine throttle opening signal that is greater than the "accelerator pedal" signal, the "hand throttle lever" controls the engine speed. At this time, the automatic transmission control system also implements the "gear hold" mode according to the signal, which is a control strategy that keeps the current gear in place without shifting, in order to reduce the vehicle speed fluctuation caused by speed adjustment during gear shifting, thereby affecting the quality of operation.

[0010] In step 6, if the driving resistance from the ground changes randomly during the operation, the engine and operating system will make adaptive adjustments to cope with the change while maintaining the gear position.

[0011] In step 6, if the engine speed drops significantly due to high running resistance and reaches the set lower limit, the clutch should be disengaged in time to avoid stalling. The gear should be downshifted according to the current vehicle speed while the engine keeps idling. At the same time, the instrument panel and buzzer should prompt the driver to intervene manually in order to exit the "gear holding" mode.

[0012] In step 6, the driver can operate the accelerator pedal and reduce the opening of the throttle lever to intervene in time. When the throttle pedal output signal is greater than the throttle lever output signal, it means that the "gear holding" mode can be exited. At this time, the automatic transmission control system re-engages the clutch to drive in a low gear suitable for the current vehicle speed. The driver controls the vehicle operation through the accelerator pedal and implements automatic gear shifting control to select the best gear. During this period, the driver should operate the throttle lever back to the initial position until the current complex situation is overcome. Then, the driver can operate the throttle lever again to return to the "gear holding" mode to drive at a stable operating speed.

[0013] The present invention has the following beneficial effects: This invention makes full use of the tractor's unique "hand throttle push lever" signal to implement the "gear holding" function, effectively avoiding the adverse effects of speed fluctuations caused by gear shifting on the working speed during operation. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Figure 1 This is a flowchart of the control method of the present invention. Detailed Implementation

[0016] The following is a further explanation of specific implementation methods.

[0017] Example 1: Taking the current target tractor as an example, it uses a diesel engine as the power source, and the automatic transmission system is equipped with a six-speed main transmission and high and low gear auxiliary transmissions. It is also equipped with two wet clutch systems to control forward and reverse travel, so it can achieve the transmission requirements of 12 forward gears and 12 reverse gears during operation.

[0018] The cab is equipped with a gear shift lever for selecting forward, neutral, and reverse driving modes; a high / low gear switch for selecting high and low gears; and the driver can control the vehicle's power demand through the accelerator pedal and the hand throttle lever. The hand throttle lever is mainly used for engine speed control during field operations to prevent speed fluctuations caused by the driver's inability to maintain a stable accelerator pedal opening for extended periods.

[0019] Based on this, the present invention proposes an automatic gear shifting control method in agricultural machinery operation mode, which is described in detail below: The specific steps of the method are as follows: Step 1, Begin; Step 2, System self-check; Step 3: Start the engine and prepare for driving; Step 4: Determine if the gear shift lever is in neutral; if yes, the clutch disengages and power is interrupted, and continue to determine if the gear shift lever is in neutral; if no, proceed to step 5. Step 5, start the vehicle; Step 6: Determine if the "accelerator pedal" signal is greater than the "hand throttle lever" signal; if so, implement automatic gear shifting according to the system strategy, and continue to determine if the "accelerator pedal" signal is greater than the "hand throttle lever" signal; if not, proceed to Step 7. Step 7, implement "gear hold" mode; Step 8: Determine if the engine speed is less than the set value; if not, return to step 6; if yes, proceed to step 9. Step 9: Disengage the clutch, allow the engine to idle, prompt the driver to manually intervene and select the target low gear based on the vehicle speed in real time; then return to step 4.

[0020] Furthermore, the specific method of step 6 is as follows: the driver starts the engine as usual, operates the "gear lever" to select the forward or reverse mode of the vehicle, and after starting, through the "accelerator pedal" opening signal and the current "vehicle speed", performs normal automatic gear shifting operation according to the set gear shifting strategy until the ideal gear and vehicle speed suitable for this operation are obtained.

[0021] Furthermore, in step 6, when the driver manipulates the "hand throttle lever" to output an engine throttle opening signal that is greater than the "accelerator pedal" signal, the "hand throttle lever" implements engine speed control, i.e. vehicle speed control. At this time, the automatic transmission control system also implements the "gear hold" mode synchronously according to the signal, i.e., the control strategy of maintaining the current gear without shifting, so as to reduce the vehicle speed fluctuation caused by speed adjustment during the shifting process, thereby affecting the quality of operation.

[0022] Furthermore, in step 6, if the driving resistance from the ground changes randomly during the operation, the engine and operating system will make adaptive adjustments to cope with this during the gear holding period.

[0023] Furthermore, in step 6, if the engine speed drops significantly due to high running resistance and reaches the set lower limit, in order to avoid stalling, the clutch is disengaged in time, and the gear is downshifted according to the current vehicle speed while the engine is kept idling. At the same time, the instrument panel and buzzer prompt the driver to make human intervention in order to exit the "gear holding" mode.

[0024] Furthermore, in step 6, the driver can manipulate the accelerator pedal and reduce the opening of the throttle lever to intervene in a timely manner. When the throttle pedal output signal is greater than the throttle lever output signal, it indicates that the "gear holding" mode can be exited. At this time, the automatic transmission control system re-engages the clutch to drive in a low gear suitable for the current vehicle speed. The driver controls the vehicle operation through the accelerator pedal and implements automatic gear shifting control to select the optimal gear. During this period, the driver should manipulate the throttle lever back to the initial position until the current complex situation is overcome. Then, the driver can manipulate the throttle lever again to return to the "gear holding" mode to drive at a stable operating speed.

Claims

1. An automatic shift control method in an agricultural machine work mode, characterized by, The driver's cab is equipped with: The gear shift lever is used to select the driving mode: forward, neutral, and reverse. "High / low speed switch" is used to select between high and low speeds; The accelerator pedal and throttle lever are used by the driver to control the vehicle speed and meet the vehicle's power requirements. The "hand throttle push lever" is used for engine speed control during field operations to prevent vehicle speed fluctuations caused by the driver's inability to maintain a fixed opening of the "accelerator pedal" for an extended period of time. In the tractor farmland operation mode, the method uses the "hand throttle push lever" signal as one of the reference signals for the automatic transmission shift control strategy, and designs a "gear hold" mode and exit mechanism to ensure that the automatic transmission gears switch reasonably according to the driver's intentions to meet the operation requirements. The specific steps of the method are as follows: Step 1, Begin; Step 2, System self-check; Step 3: Start the engine and prepare for driving; Step 4: Determine if the gear shift lever is in neutral; if yes, the clutch disengages and power is interrupted, and continue to determine if the gear shift lever is in neutral; if no, proceed to step 5. Step 5, start the vehicle; Step 6: Determine if the "accelerator pedal" signal is greater than the "hand throttle lever" signal; if so, implement automatic gear shifting according to the system strategy, and continue to determine if the "accelerator pedal" signal is greater than the "hand throttle lever" signal; if not, proceed to Step 7. Step 7: Implement "gear hold" mode; Step 8: Determine if the engine speed is less than the set value; if not, return to step 6; if yes, proceed to step 9. Step 9: Disengage the clutch, allow the engine to idle, prompt the driver to manually intervene and select the target low gear based on the vehicle speed in real time; then return to step 4. In step 6, when the driver manipulates the "hand throttle lever" to output an engine throttle opening signal that is greater than the "accelerator pedal" signal, the "hand throttle lever" controls the engine speed. At this time, the automatic transmission control system also implements the "gear hold" mode according to the signal, which is a control strategy that keeps the current gear in place without shifting, in order to reduce the vehicle speed fluctuation caused by speed adjustment during gear shifting, thereby affecting the quality of operation.

2. The automatic gear shift control method in the agricultural machine work mode according to claim 1, characterized in that, The specific method of step 6 is as follows: The driver starts the engine as usual, operates the "gear lever" to select the forward or reverse mode of the vehicle, and after starting, performs normal automatic gear shifting operation according to the set gear shifting strategy through the "accelerator pedal" opening signal and the current "vehicle speed" until the ideal gear and vehicle speed suitable for this operation are obtained.

3. The automatic gear shifting control method in an agricultural machinery operation mode according to claim 1, characterized in that, In step 6, if the driving resistance from the ground changes randomly during the operation, the engine and operating system will make adaptive adjustments to cope with the change while maintaining the gear position.

4. The automatic gear shifting control method in an agricultural machinery operation mode according to claim 1, characterized in that, In step 6, if the engine speed drops significantly due to high running resistance and reaches the set lower limit, the clutch should be disengaged in time to avoid stalling. The gear should be downshifted according to the current vehicle speed while the engine keeps idling. At the same time, the instrument panel and buzzer should prompt the driver to intervene manually in order to exit the "gear holding" mode.

5. The automatic gear shifting control method in an agricultural machinery operation mode according to claim 1, characterized in that, In step 6, the driver can operate the accelerator pedal and reduce the opening of the throttle lever to intervene in time. When the throttle pedal output signal is greater than the throttle lever output signal, it means that the "gear holding" mode can be exited. At this time, the automatic transmission control system re-engages the clutch to drive in a low gear suitable for the current vehicle speed. The driver controls the vehicle operation through the accelerator pedal and implements automatic gear shifting control to select the best gear. During this period, the driver should operate the throttle lever back to the initial position until the current complex situation is overcome. Then, the driver can operate the throttle lever again to return to the "gear holding" mode to drive at a stable operating speed.

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