CN-122014848-A - Method and computer program product for adjusting the position of a fork of a vehicle gearbox

Abstract

The invention provides a method and a computer program product for adjusting the shifting fork position of a vehicle gearbox. The method comprises the steps of monitoring the distance between a shifting fork and a reference point, wherein the reference point is the center position between a first gear and a second gear, comparing the distance with a first distance threshold, and reducing torque transmitted by the two-gear gearbox if the distance is smaller than the first distance threshold. According to the method provided by the invention, the shifting fork component deviating from the full-tooth-width engagement position can be quickly adjusted back to the full-tooth-width engagement position, so that the transmission of the vehicle can transmit the torque as large as possible from the motor to the wheel end of the vehicle, and meanwhile, the unexpected gear-releasing fault of the vehicle is avoided.

Inventors

• WU JIAPENG
• QIU HAIQIANG

Assignees

• 博世动力总成有限公司

Dates

Publication Date

20260512

Application Date

20241111

Claims (20)

1. 1. A method of adjusting a shift fork position of a vehicle transmission, the vehicle transmission being a two-speed transmission comprising a first gear and a second gear, the shift fork being configured for engagement with the first gear or the second gear, the method comprising: Monitoring the distance between the shifting fork and a reference point, wherein the reference point is the center position between the first gear and the second gear; comparing the distance to a first distance threshold; and if the distance is smaller than the first distance threshold value, reducing the torque transmitted by the two-gear gearbox.
2. 2. The method according to claim 1, wherein the method further comprises: comparing the distance to a second distance threshold that is less than the first distance threshold; If the distance is less than the first distance threshold but above the second distance threshold, reducing the torque transferred by the two speed gearbox comprises reducing the torque transferred by the two speed gearbox to a constant first torque.
3. 3. The method according to claim 2, wherein the method further comprises: Comparing the distance to a third distance threshold that is less than the second distance threshold; Reducing the torque transferred by the two speed gearbox if the distance is less than the second distance threshold but above the third distance threshold comprises reducing the torque transferred by the two speed gearbox to a second torque, wherein the second torque gradually decreases as the distance decreases and the maximum value of the second torque is equal to the first torque.
4. 4. A method according to claim 3, wherein the second torque decreases from the first torque to 0 as the distance decreases.
5. 5. The method of claim 3, wherein the step of, And when the distance is smaller than the second distance threshold value but is above the third distance threshold value, the second torque applied in the process of gradually rising the torque transmitted by the two-gear gearbox is smaller than the second torque applied in the process of gradually falling the torque transmitted by the two-gear gearbox.
6. 6. A method according to claim 3, characterized in that the method further comprises: comparing the distance to a fourth distance threshold that is less than the third distance threshold; If the distance is less than the third distance threshold but above the fourth distance threshold, reducing the torque transferred by the two speed gearbox comprises reducing the torque transferred by the two speed gearbox to a constant third torque, the third torque being equal to a minimum of the second torque.
7. 7. The method of claim 6, wherein the step of providing the first layer comprises, The third torque is equal to 0.
8. 8. The method of claim 6, wherein the method further comprises: and if the distance is smaller than the fourth distance threshold, controlling the shifting fork to re-shift, wherein the shifting fork is moved to the reference point first and then moved back by a distance larger than the first distance threshold.
9. 9. The method according to claim 1, wherein the method further comprises: starting timing and continuously monitoring the distance between the shifting fork and the reference point after reducing the torque transmitted by the two-gear gearbox; And if the distance is still smaller than the first distance threshold after a preset time period, controlling the shifting fork to re-shift, wherein the shifting fork is moved to the reference point and then moved back by a distance larger than the first distance threshold.
10. 10. The method according to claim 8 or 9, characterized in that the method further comprises: and before controlling the shifting fork to re-shift, sending an alarm to a driver, and not releasing the alarm until the distance is greater than or equal to the first distance threshold value.
11. 11. The method of claim 6, wherein the first distance threshold is equal to 8.5mm, the second distance threshold is equal to 7.5mm, the third distance threshold is equal to 7.2mm, and the fourth distance threshold is equal to 6.6mm.
12. 12. A method of adjusting a shift fork position of a vehicle transmission, the transmission comprising a gear, the shift fork being configured for engagement with the gear, the method comprising: monitoring the engagement between the fork and the gear, and And if the distance between the shifting fork and the gear is larger than or equal to a fifth distance threshold value, reducing the torque transmitted by the gearbox.
13. 13. The method of claim 12, wherein monitoring engagement between the fork and the gear comprises: and selecting any reference point, and determining the positions of the gear and the shifting fork relative to the reference point, so as to determine the distance between the gear and the shifting fork.
14. 14. The method according to claim 12, wherein the method further comprises: And if the distance between the shifting fork and the gear is larger than or equal to the fifth distance threshold value but smaller than a sixth distance threshold value, reducing the torque transmitted by the gearbox to be a constant first torque.
15. 15. The method of claim 14, wherein the method further comprises: And if the distance between the shifting fork and the gear is larger than or equal to the sixth distance threshold value but smaller than a seventh distance threshold value, reducing the torque transmitted by the gearbox to a second torque, wherein the second torque gradually decreases along with the increase of the distance, and the maximum value of the second torque is equal to the first torque.
16. 16. The method of claim 15, wherein the method further comprises: And if the distance between the shifting fork and the gear is larger than or equal to the second distance threshold value but smaller than an eighth distance threshold value, reducing the torque transmitted by the gearbox to a constant third torque, wherein the third torque is equal to the minimum value of the second torque.
17. 17. The method according to claim 15, wherein in the case where the distance between the fork and the gear is greater than or equal to the sixth distance threshold but less than a seventh distance threshold, the second torque applied during the gradual increase of the torque transmitted by the gearbox is less than the second torque applied during the gradual decrease of the torque transmitted by the gearbox.
18. 18. The method of claim 16, wherein the method further comprises: And if the distance between the shifting fork and the gear is greater than or equal to the eighth distance threshold, controlling the shifting fork to re-engage, wherein the shifting fork is moved to a neutral position and then moved back to the gear, so that the distance between the shifting fork and the gear is smaller than the fifth distance threshold.
19. 19. The method according to claim 12, wherein the method further comprises: starting timing and continuously monitoring the distance between the shifting fork and the gear after reducing the torque transmitted by the gearbox; And if the distance is still greater than or equal to the fifth distance threshold after a predetermined period of time, controlling the shifting fork to re-shift, wherein the shifting fork is moved to a neutral position and then moved back to the gear so that the distance between the shifting fork and the gear is less than the fifth distance threshold.
20. 20. A computer program product comprising a computer program comprising instructions, characterized in that when the instructions are caused by a processor the processor implements the method according to any of claims 1-19.

Description

Method and computer program product for adjusting the position of a fork of a vehicle gearbox Technical Field The invention relates to the technical field of vehicle gearboxes, in particular to a method for adjusting the position of a shifting fork of a vehicle gearbox, which aims to ensure that a shifting fork component and a gear are in full-tooth-width joint state and avoid unexpected gear disengagement faults of a vehicle. The invention also relates to a computer program product comprising program instructions for causing a processor to carry out the above method when executed on the processor. Background In a transmission system of a vehicle, torque can be smoothly transmitted from a motor to a wheel end through a fork assembly and a gear only when the fork assembly is fully engaged with a coupling tooth on a certain gear with full tooth width. Once engaged, such as when the fork assembly is not engaged with the coupling teeth on the gear at full tooth width, but is engaged with the coupling teeth on the gear at only partial tooth width, torque that can be transferred will be limited or other measures need to be taken to protect the transmission system. Otherwise, the transmission system is likely to suffer mechanical damage. On the other hand, if no protective action is taken to bring the fork assembly back from the partial-width engaged position to the full-width engaged position during torque transmission, the fork assembly will typically float and get closer to the "neutral" position, causing an unexpected out-of-gear fault. Moreover, the greater the torque transferred, the greater the risk of an unexpected out-of-gear fault. This is dangerous and highly undesirable. The present invention has been made in view of the above background. Disclosure of Invention The present invention provides a method and computer program product for adjusting the shift fork position of a vehicle transmission, which solves one or more of the problems of the prior art. According to the method provided by the invention, the shifting fork component deviating from the full-tooth-width engagement position can be quickly adjusted back to the full-tooth-width engagement position, so that the transmission of the vehicle can transmit the torque as large as possible from the motor to the wheel end of the vehicle, and meanwhile, the unexpected gear-off fault of the vehicle is avoided. In particular, in a first aspect of the invention, a method of adjusting the position of a fork of a vehicle gearbox is proposed, the vehicle gearbox being a two-speed gearbox comprising a first gear and a second gear, the fork being configured for engagement with the first gear or the second gear, wherein the method comprises monitoring a distance between the fork and a reference point, wherein the reference point is a central position between the first gear and the second gear, comparing the distance with a first distance threshold, and reducing torque transmitted by the two-speed gearbox if the distance is smaller than the first distance threshold. In a second aspect of the invention, a method of adjusting a shift fork position of a vehicle gearbox is presented, the gearbox comprising a gear wheel, the shift fork being configured for engagement with the gear wheel, wherein the method comprises monitoring an engagement condition between the shift fork and the gear wheel, and reducing torque transmitted by the gearbox if a distance between the shift fork and the gear wheel is equal to or greater than a fifth distance threshold. In a third aspect of the invention, a computer program product is presented, the computer program product comprising a computer program comprising program instructions, wherein the program instructions, when executed by a processor, cause the processor to carry out the method of the first aspect. In general, the various embodiments of the invention may be combined and coupled in any way possible within the scope of the invention. These and other aspects, features and/or advantages of the present invention will become apparent from and elucidated with reference to the embodiments described hereinafter. Drawings Embodiments of the present invention will now be described, by way of example only, with reference to the following drawings, in which: FIG. 1a schematically illustrates a two-speed gearbox of a vehicle with a fork assembly of the gearbox in a full-face engagement position; FIG. 1b schematically illustrates the two-speed transmission of FIG. 1a with the shift fork assembly of the transmission in a partially engaged position, and FIG. 2 schematically illustrates torque limiting curves applied to a transmission, based on some of which a method of adjusting a shift fork position of a vehicle transmission according to one embodiment of the invention can be implemented. It is to be understood that the drawings are designed solely for the purposes of illustrating certain specific embodiments of the invention and that it shou