CN110792765B - Self-learning control method and system for gear position of gearbox - Google Patents
Self-learning control method and system for gear position of gearbox Download PDFInfo
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- CN110792765B CN110792765B CN201810871432.8A CN201810871432A CN110792765B CN 110792765 B CN110792765 B CN 110792765B CN 201810871432 A CN201810871432 A CN 201810871432A CN 110792765 B CN110792765 B CN 110792765B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/02—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing characterised by the signals used
- F16H61/0202—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing characterised by the signals used the signals being electric
- F16H61/0204—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing characterised by the signals used the signals being electric for gearshift control, e.g. control functions for performing shifting or generation of shift signal
Abstract
The invention relates to a self-learning control method and a self-learning control system for gear positions of a gearbox, which comprise the following steps: 1) controlling a gear selection motor to drive a gear shifting point to move towards a gear to be learned, and recording the current position of the gear shifting point when the gear selection motor is locked; 2) controlling a gear selection motor to drive a gear shifting finger to move a set small distance from the current position to the direction far away from the gear to be learned; after the set small distance is moved, continuously controlling a gear selection motor to keep driving the gear shifting to move in a direction away from the gear to be learned; 3) and if the rotating speed of the motor is zero in the process of moving or after the set short distance, considering that the locked rotor in the step 1) reaches the limit position of the gear to be learned, and considering that the recorded position in the step 1) is the limit position of the gear to be learned. The invention can accurately distinguish the two states before and after the tooth, can effectively judge whether the single learning is successful, and can ensure the accuracy of the self-learning of the gears.
Description
Technical Field
The invention relates to a self-learning control method and a self-learning control system for gear positions of a gearbox, and belongs to the field of self-learning of gearboxes.
Background
Currently, with the rapid development of new energy passenger cars, AMTs have gradually become an important component of new energy passenger cars. At present, an electric control electric gear shifting mechanism is used more, and the position of a gear shifting finger is fed back by an electric gear shifting multipurpose displacement sensor at present at all times to serve as the eye of an AMT controller. The control system needs to accurately know the feedback value of the displacement sensor corresponding to each gear (hereinafter referred to as the calibration position of each gear) and the feedback value of the sensor corresponding to the current gear shifting finger position to realize normal and effective gear shifting. However, due to the problem of production consistency, it is often impossible to manually calibrate the calibration position of each gear for each gearbox, so that the control system is required to automatically identify these values.
At present, the common method is that a control system controls a gear shifting motor to rotate forwards or reversely, as shown in a two-gear AMT gear schematic diagram shown in fig. 1, the gear shifting motor rotates to drive a lead screw, so that a gear shifting finger 1 moves towards a 1-gear direction and a 2-gear direction respectively, the gear shifting motor is blocked, namely the gear shifting finger reaches a 1-gear position or a 2-gear position, and a voltage value fed back by a displacement sensor at the moment is regarded as a calibration position of the 1-gear or the 2-gear.
Due to the problem of the gear meshing structure of the gearbox, the phenomenon that the gearbox is damaged or the learning is unsuccessful due to improper gear top teeth and gear shifting motor torque output in the self-learning process can often occur.
Disclosure of Invention
The invention aims to provide a self-learning control method and a self-learning control system for gear positions of a gearbox, which are used for solving the problem of unsuccessful learning, such as damage of the gearbox and the like, caused by improper torque output of gear top teeth and a gear shifting motor in the self-learning process of the gearbox.
In order to achieve the above object, the scheme of the invention comprises:
the invention discloses a self-learning control method for gear positions of a gearbox, which comprises the following steps of:
1) controlling a gear selection motor to drive gear shifting to point to the direction of a gear to be learned to move, and recording the current position of the gear shifting finger when the gear selection motor is locked;
2) controlling a gear selection motor to drive a gear shifting finger to move from the current position to the direction far away from the gear to be learned;
3) and if the rotating speed of the motor is detected to be zero, recording the current position of the gear shifting finger as the limit position of the gear to be learned.
The invention can accurately distinguish the two states before and after the tooth, can effectively judge whether the single learning is successful, and can ensure the accuracy of the self-learning of the gears.
Further, in the step 3), if the rotation speed of the motor is detected not to be zero, it is judged that gear top teeth appear, and gear position self-learning is conducted again.
The invention can actively and accurately judge the top tooth phenomenon in single learning, and automatically control and repair the top tooth and carry out self-learning again after the self-learning fails due to the top tooth. The condition that self-learning needs to be repeated for several times to ensure accurate learning in the prior art is changed, and the time consumed by the self-learning of the gearbox is shortened.
Further, the method for judging the occurrence of locked rotor of the gear selecting motor comprises the following steps: and detecting that the current of the gear selecting motor is greater than a set value and the rotating speed of the motor is zero.
The motor locked rotor is determined by detecting the motor current, and whether the motor is locked rotor is judged according to the standard that whether the motor current reaches the locked rotor current, so that the method is simple and reliable.
Further, the manner of implementing the step 2) is as follows: and sending a reverse rotation instruction to the gear selection motor, wherein the reverse rotation instruction enables the gear selection motor to drive the gear shifting finger to move a preset distance from the current position to the direction far away from the gear to be learned, and the preset distance is smaller than the length of the current gear.
The invention also provides a self-learning control method for the gear position of the gearbox, which comprises the following steps:
A. controlling a gear selection motor to drive gear shifting to move towards the direction of a gear to be learned until the gear selection motor is locked;
B. controlling a gear selection motor to drive a gear shifting finger to move from the current position to the direction far away from the gear to be learned;
C. and if the rotating speed of the motor is detected to be zero, the gear selection motor is controlled again to drive the gear to be learned to shift, and when the gear selection motor is locked, the current position of the gear shifting finger is recorded and calibrated to be the limit position of the gear to be learned.
And after the top teeth do not appear or the locked rotor caused by the top teeth is judged and solved, the gear is shifted again and the position is recorded, the gear is guaranteed to reach the limit position of the gear, and the gear position recorded by self-learning is guaranteed to be in a state of leaning against the gear.
Further, in the step C), if the rotation speed of the motor is detected not to be zero, the gear top teeth are judged to appear, and the gear position self-learning is carried out again.
Further, the method for judging the occurrence of locked rotor of the gear selecting motor comprises the following steps: and detecting that the current of the gear selecting motor is greater than a set value and the rotating speed of the motor is zero.
Further, the method for implementing the step B) is as follows: and sending a reverse rotation instruction to the gear selection motor, wherein the reverse rotation instruction enables the gear selection motor to drive the gear shifting finger to move a preset distance from the current position to the direction far away from the gear to be learned, and the preset distance is smaller than the length of the current gear.
The invention also provides a self-learning control system for the gear position of the gearbox, which comprises a controller, wherein the controller is used for executing instructions for realizing the method.
Drawings
FIG. 1 is a schematic diagram of two-gear AMT gears;
FIG. 2 is a flow chart of a self-learning control method for gear positions of a transmission according to embodiment 1 of the invention;
fig. 3 is a flow chart of a self-learning control method for gear positions of a transmission according to embodiment 2 of the invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The two-gear AMT gearbox is taken as an example (but not limited to two gears), but the core of the two-gear AMT gearbox is that the fault phenomenon of the top gear is actively judged and actively solved in the self-learning process, the accuracy and reliability of gear learning are improved, and the problem that the gear top gear causes learning failure or inaccurate gear disengagement is prevented.
Fig. 1 shows a gear diagram of a two-gear AMT transmission, which includes a shift finger 1, a neutral gear 2, a 1-gear 3, and a 2-gear 4. The gear shifting finger 1 is driven and controlled by a gear selecting motor through a meshed gear rack, and can move towards the 1-gear or 2-gear direction, when the gear shifting finger enters the 1-gear, the gear shifting finger is locked in the 1-gear area, and the gearbox is engaged in the 1-gear; when the gear shifting finger enters a 2-gear, the gear shifting finger is locked in a 2-gear area, and the gearbox is engaged in a 2-gear.
When the control system is used for shifting gears, the gear position needs to be known at the moment, the output value of the corresponding sensor needs to be detected, and the calibration of the output value of the corresponding sensor of the corresponding gear in the gear state is the gear position self-learning.
As shown in fig. 2, the self-learning control process of the gear position of the transmission according to the embodiment, taking 1-gear learning as an example, includes the following steps:
a) triggering a self-learning process (the vehicle needs to meet a parking state, and a hand brake is pulled up to ensure safety);
b) the main driving motor (gear selecting motor) gives a torque control command, the target value of the torque is changed, and the fluctuation of the rotating speed of the driving motor in the idle condition within 20-50rpm (low rotating speed) is ensured;
c) controlling a gear selection motor to enable a gear shifting point to move in a 1-gear direction (small torque can be adopted), and recording the current position of a gear shifting finger (output values of corresponding sensors can be detected and recorded as position marks) when the gear selection motor is locked (judged by detecting locked current) and the rotating speed is 0rpm (a set threshold value, such as 10rpm, can also be adopted);
d) and sending a control instruction to the gear selecting motor, and controlling the gear selecting motor to move a small distance in the reverse direction of the 1 gear based on the recorded position (ensuring that if the gear is in the 1 gear, the gear is still required to be in a gear state after the small distance is moved). If the rotating speed of the gear selecting motor is not zero, namely the gear shifting finger moves, the gear shifting finger does not enter a 1-gear range region and is not locked in the 1-gear range region, the fact that faults such as top teeth and the like occur in the process of c) just before, a gear and a rack are blocked, the gear and the rack cannot be successfully engaged in the 1-gear range is indicated, learning fails at the moment, and the process of c) needs to be repeated; if the rotating speed of the gear selecting motor is zero, namely the gear shifting finger is not moved, indicating that the process of the previous step c) is to enter a 1-gear range or reach a 1-gear limit position (the gear shifting finger is locked into the 1-gear range, so that the motor cannot rotate continuously);
e) and c), the position of the gear shifting finger recorded in the step c) is the limit position of the 1 st gear, and the learning is finished.
The learning process of the 2 nd gear is similar to the 1 st gear, and is not described in detail herein.
As shown in fig. 3, the self-learning control process of the gear position of the transmission according to the embodiment, taking 1-gear learning as an example, includes the following steps:
1) triggering a self-learning process (the vehicle needs to meet a parking state, and a hand brake is pulled up to ensure safety);
2) the main driving motor (gear selecting motor) gives a torque control command, the target value of the torque is changed, and the fluctuation of the rotating speed of the driving motor in the idle condition within 20-50rpm (low rotating speed) is ensured;
3) controlling a gear selection motor to enable a gear shift to move towards a 1-gear direction (small torque can be adopted), and stopping moving when the gear selection motor is locked (judged by detecting locked current) and the rotating speed is 0rpm (a set threshold value, such as 10rpm, can also be adopted);
4) and sending a control instruction to the gear selecting motor, and controlling the gear selecting motor to move a small distance in the reverse direction of the 1 gear based on the recorded position (ensuring that if the gear is in the 1 gear, the gear is still required to be in a gear state after the small distance is moved). If the rotating speed of the gear selecting motor is not zero, namely the gear shifting finger moves, the gear shifting finger does not enter a 1-gear range region and is not locked in the 1-gear range region, the faults such as top teeth and the like occur in the process of 3), a gear and a rack are blocked, the gear and the rack cannot be successfully engaged in the 1-gear range, at this time, learning fails, and the process of 3) needs to be repeated; if the rotating speed of the gear selecting motor is zero, namely the gear shifting finger is not moved, indicating that 3) the process is to enter a 1-gear range or reach a 1-gear limit position (the gear shifting finger is locked into the 1-gear range, so that the motor cannot rotate continuously);
5) and continuously controlling the gear selecting motor to drive the gear shifting to move towards the 1-gear direction (the torque can be slightly increased to ensure that the gear shifting finger moves to the 1-gear limit position), and recording the current position as the 1-gear limit position when the gear selecting motor is locked (through locked current detection) and the rotating speed of the driving motor is 0 rpm.
The learning process of the 2 nd gear is similar to the 1 st gear, and is not described in detail herein.
The key of the invention for increasing the self-learning success rate is that in the self-learning process of the gearbox, the probability of faults such as top teeth and the like in the learning process is reduced through the low-speed rotation of the driving motor at the input shaft end of the gearbox.
The key of the gear-shifting failure caused by the conditions of top teeth and the like is that the gear-shifting finger reversely rotates after locked-rotor, the self-learning process is divided into two processes before and after the tooth by taking whether the gear-shifting finger can reversely rotate for a proper distance as a tooth judging basis, the small torque of the gear-shifting motor is used before meshing to avoid the impact of the top teeth, and the larger torque of the gear-shifting motor is used after meshing to ensure that the gear-shifting finger smoothly reaches the limit position.
As another embodiment, the present invention may also use the position recorded when a failure such as a tooth top does not occur during locked-rotor as the limit position of the shift position; the motor locked rotor can be judged only through the locked rotor current without detecting the rotating speed.
Claims (7)
1. A self-learning control method for gear positions of a gearbox is characterized by comprising the following steps:
1) controlling a gear selection motor to drive gear shifting to point to the direction of a gear to be learned to move, and recording the current position of the gear shifting finger when the gear selection motor is locked;
2) controlling a gear selection motor to drive a gear shifting finger to move from the current position to the direction far away from the gear to be learned;
3) if the rotating speed of the motor is detected to be zero, the recorded current position of the gear shifting finger is the limit position of the gear to be learned;
and 3) judging that gear top teeth appear if the rotating speed of the motor is detected not to be zero, and re-learning the gear position.
2. The self-learning control method for the gear position of the gearbox as recited in claim 1, wherein: the method for judging the locked rotor of the gear selecting motor comprises the following steps: and detecting that the current of the gear selecting motor is greater than a set value and the rotating speed of the motor is zero.
3. The self-learning control method for the gear position of the gearbox as recited in claim 2, wherein: the mode for realizing the step 2) is as follows: and sending a reverse rotation instruction to the gear selection motor, wherein the reverse rotation instruction enables the gear selection motor to drive the gear shifting finger to move a preset distance from the current position to the direction far away from the gear to be learned, and the preset distance is smaller than the length of the current gear.
4. A self-learning control method for gear positions of a gearbox is characterized by comprising the following steps:
A. controlling a gear selection motor to drive gear shifting to move towards the direction of a gear to be learned until the gear selection motor is locked;
B. controlling a gear selection motor to drive a gear shifting finger to move from the current position to the direction far away from the gear to be learned;
C. if the rotation speed of the motor is detected to be zero, the gear selection motor is controlled again to drive the gear to be learned to shift, and when the gear selection motor is locked, the current position of the gear shifting finger is recorded and calibrated to be the limit position of the gear to be learned;
and C), judging that gear top teeth appear if the rotation speed of the motor is not zero, and re-learning the gear position.
5. The self-learning control method for the gear position of the gearbox as recited in claim 4, wherein: the method for judging the locked rotor of the gear selecting motor comprises the following steps: and detecting that the current of the gear selecting motor is greater than a set value and the rotating speed of the motor is zero.
6. The self-learning control method for the gear position of the gearbox as recited in claim 5, wherein: the mode for realizing the step B) is as follows: and sending a reverse rotation instruction to the gear selection motor, wherein the reverse rotation instruction enables the gear selection motor to drive the gear shifting finger to move a preset distance from the current position to the direction far away from the gear to be learned, and the preset distance is smaller than the length of the current gear.
7. A gearbox gear position self-learning control system, characterized by comprising a controller for executing instructions for implementing the method according to any one of claims 1 to 6.
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| CN201810871432.8A CN110792765B (en) | 2018-08-02 | 2018-08-02 | Self-learning control method and system for gear position of gearbox |
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| CN201810871432.8A CN110792765B (en) | 2018-08-02 | 2018-08-02 | Self-learning control method and system for gear position of gearbox |
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| CN112268697B (en) * | 2020-10-28 | 2022-07-29 | 坤泰车辆系统（常州）有限公司 | Method for testing double-clutch automatic gearbox in segmented mode |
| CN113803461B (en) * | 2021-09-28 | 2023-06-02 | 东风汽车有限公司东风日产乘用车公司 | Gear position determining method, device and equipment based on self-learning and storage medium |
| CN114165582B (en) * | 2021-11-05 | 2023-06-23 | 潍柴动力股份有限公司 | AMT gearbox, AMT gearbox gear self-learning method, device, equipment and medium |
| CN115123176A (en) * | 2022-01-07 | 2022-09-30 | 长城汽车股份有限公司 | Control method and device for gear-to-gear phenomenon of gearbox and vehicle |
| CN117404464B (en) * | 2023-12-13 | 2024-04-09 | 质子汽车科技有限公司 | New energy vehicle gear shifting control method and electronic equipment |
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Address after: 450061 Yutong Road, Guancheng District, Zhengzhou City, Henan Province Patentee after: Yutong Bus Co., Ltd Address before: 450061 Yutong Road, Guancheng District, Zhengzhou City, Henan Province Patentee before: Zhengzhou Yutong Bus Co., Ltd |