Dual-clutch transmission reverse gear control method and vehicle

Abstract

This application provides a reverse gear control method for a dual-clutch transmission, belonging to the field of transmission control. When a synchronizer is shared between the reverse gear and a preset forward gear, if the synchronizer is not successfully synchronized with the reverse gear (i.e., reverse gear engagement fails), the synchronizer is controlled to move in the opposite direction. This allows the synchronizer to first synchronize with the preset forward gear, thus fine-tuning the synchronizer's position. Then, the connection between the synchronizer and the preset forward gear is disconnected, and an attempt is made to synchronize the synchronizer with the reverse gear again. Because the synchronizer's position is fine-tuned using the preset forward gear corresponding to the reverse gear first, the success rate of synchronization between the synchronizer and the reverse gear is increased, thus improving the success rate of engaging reverse gear.

Description

Technical Field

[0001] This application relates to the field of transmission control, and in particular to a method for controlling the reverse gear of a dual-clutch transmission and a vehicle thereof. Background Technology

[0002] Dual-clutch transmissions have gained popularity among automakers due to their advantages such as fast gear shifting speed, and more and more models are choosing to be equipped with dual-clutch transmissions.

[0003] Synchronizers, as a crucial component of transmissions, synchronize the positions of two gears about to mesh, preventing gear grinding. Double-cone synchronizers can increase the synchronizing torque, allowing for better gear engagement. However, to reduce manufacturing and assembly costs, dual-clutch transmissions often use single-cone synchronizers for reverse gear, which provide a smaller synchronizing torque compared to double-cone synchronizers.

[0004] Due to the special gear ratio of the reverse gear, a large shifting force is required to engage reverse gear. If there is a large difference in position between the reverse synchronizer and the reverse gear, especially when the temperature is low and the lubricating oil viscosity is low, the synchronizing torque provided by the single-cone reverse synchronizer may not be sufficient to synchronize the difference, resulting in jamming and inability to engage reverse gear. Summary of the Invention

[0005] In view of this, this application provides a reverse gear control method for a dual-clutch transmission, which can improve the success rate of engaging reverse gear:

[0006] On the one hand, this application provides a method for controlling the reverse gear of a dual-clutch transmission, the method comprising:

[0007] When a command to engage reverse gear is received, the synchronizer is controlled to move closer to the reverse gear, and the synchronizer and the reverse gear are monitored to ensure that they are successfully synchronized.

[0008] When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0009] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0010] Alternatively, the method may also include:

[0011] When it is detected that the synchronizer and reverse gear are not synchronized, the number of synchronization failures is accumulated from zero, and it is determined whether the number of synchronization failures is greater than the preset number.

[0012] When it is determined that the number of synchronization failures is not greater than the preset number, the synchronizer is first separated from the reverse gear and then moves towards the reverse gear again.

[0013] When it is determined that the number of synchronization failures exceeds the preset number, the synchronizer is controlled to move away from the reverse gear and towards the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The connection between the synchronizer and the preset forward gear is disconnected, and the synchronizer is controlled to move towards the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0014] Alternatively, after disconnecting the synchronizer from the preset forward gear and controlling the synchronizer to move towards the reverse gear, the method further includes:

[0015] Monitor whether the synchronizer and reverse gear are successfully synchronized.

[0016] When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0017] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0018] Alternatively, the method may also include:

[0019] When a command to engage reverse gear is received, the synchronizer is controlled to move closer to the reverse gear, and the synchronizer and the reverse gear are monitored to ensure that they are successfully synchronized.

[0020] When it is detected that the synchronizer and the reverse gear are not synchronized and the oil temperature is lower than the preset temperature, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0021] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0022] Optionally, the preset forward gear corresponding to the preset forward gear is an even-numbered gear.

[0023] On the other hand, this application provides a vehicle including a transmission controller, a synchronizer, a reverse gear, and a preset forward gear gear, wherein the transmission controller is configured to:

[0024] When a command to engage reverse gear is received, the synchronizer is controlled to move closer to the reverse gear, and the synchronizer and the reverse gear are monitored to ensure that they are successfully synchronized.

[0025] When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0026] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0027] Alternatively, the transmission controller may also be configured as follows:

[0028] When it is detected that the synchronizer and reverse gear are not synchronized, the number of synchronization failures is accumulated from zero, and it is determined whether the number of synchronization failures is greater than the preset number.

[0029] When it is determined that the number of synchronization failures is not greater than the preset number, the synchronizer is first separated from the reverse gear and then moves towards the reverse gear again.

[0030] When it is determined that the number of synchronization failures exceeds the preset number, the synchronizer is controlled to move away from the reverse gear and towards the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The connection between the synchronizer and the preset forward gear is disconnected, and the synchronizer is controlled to move towards the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0031] Alternatively, the transmission controller may also be configured as follows:

[0032] After disconnecting the synchronizer from the preset forward gear and controlling the synchronizer to move closer to the reverse gear, monitor whether the synchronizer and the reverse gear are successfully synchronized.

[0033] When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0034] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0035] Alternatively, the transmission controller may also be configured as follows:

[0036] When a command to engage reverse gear is received, the synchronizer is controlled to move closer to the reverse gear, and the synchronizer and the reverse gear are monitored to ensure that they are successfully synchronized.

[0037] When it is detected that the synchronizer and the reverse gear are not synchronized and the oil temperature is lower than the preset temperature, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0038] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0039] Optionally, the preset forward gear corresponding to the preset forward gear is an even-numbered gear.

[0040] The reverse gear control method for dual-clutch transmissions provided in this application, when a synchronizer is shared between the reverse gear and a preset forward gear, if the synchronizer is not successfully synchronized with the reverse gear (i.e., the reverse gear fails to engage), the synchronizer is controlled to move in the opposite direction. This allows the synchronizer to first synchronize with the preset forward gear, thus fine-tuning the synchronizer's position. Then, the connection between the synchronizer and the preset forward gear is disconnected, and an attempt is made to synchronize the synchronizer with the reverse gear again. Because the position of the synchronizer is first fine-tuned using the preset forward gear corresponding to the reverse gear, the success rate of synchronizing the synchronizer with the reverse gear is increased, thus improving the success rate of engaging reverse gear. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 A flowchart of a dual-clutch transmission reverse gear control method provided in an embodiment of this application;

[0043] Figure 2 Another flowchart of the reverse gear control method for a dual-clutch transmission provided in the embodiments of this application;

[0044] Figure 3 This application provides an architectural diagram of the vehicle as an embodiment.

[0045] Figure 4 Another architectural diagram of the vehicle provided in the embodiments of this application;

[0046] Figure 5 Another architectural diagram of the vehicle provided in this application embodiment. Detailed Implementation

[0047] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0048] Due to cost pressures, dual-clutch transmissions often use a single-cone structure for the reverse gear synchronizer. This results in a low synchronizing torque for reverse gear, while requiring a large shifting force, leading to jamming or inability to engage reverse. This problem is especially common in northern winters when low temperatures and low lubricant viscosity result in insufficient lubrication, making the first start of the vehicle more prone to this issue.

[0049] The purpose of this invention is to effectively solve the problem of being unable to engage reverse gear in winter by modifying the software control strategy and changing the reverse gear control process without increasing the cost per vehicle, thereby reducing complaints from end consumers and improving the product's reputation.

[0050] This application provides a method for controlling the reverse gear of a dual-clutch transmission, which is implemented by the transmission controller, such as... Figure 1 As shown, the method includes steps S101, S102, and S103, wherein:

[0051] In step S101, when a reverse gear engagement command is received, the synchronizer is controlled to move toward the reverse gear, and the synchronizer and the reverse gear are monitored to see if they are successfully synchronized.

[0052] In step S102, when it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and towards the preset forward gear, so that the synchronizer and the preset forward gear are synchronized.

[0053] The preset forward gear and reverse gear share a synchronizer, with the preset forward gear and reverse gear located at opposite ends of the synchronizer.

[0054] In step S103, the connection between the synchronizer and the preset forward gear is disconnected, and the synchronizer is controlled to move towards the reverse gear so that the synchronizer and the reverse gear are synchronized.

[0055] In some optional embodiments, the method further includes:

[0056] When it is detected that the synchronizer and reverse gear are not synchronized, the number of synchronization failures is accumulated from zero, and it is determined whether the number of synchronization failures is greater than the preset number.

[0057] When it is determined that the number of synchronization failures is not greater than the preset number, the synchronizer is first separated from the reverse gear and then moves towards the reverse gear again.

[0058] When it is determined that the number of synchronization failures exceeds the preset number, the synchronizer is controlled to move away from the reverse gear and towards the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The connection between the synchronizer and the preset forward gear is disconnected, and the synchronizer is controlled to move towards the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0059] In some optional embodiments, after disconnecting the synchronizer from the preset forward gear and controlling the synchronizer to move towards the reverse gear, the method further includes:

[0060] Monitor whether the synchronizer and reverse gear are successfully synchronized.

[0061] When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0062] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0063] In some optional embodiments, the method further includes:

[0064] When a command to engage reverse gear is received, the synchronizer is controlled to move closer to the reverse gear, and the synchronizer and the reverse gear are monitored to ensure that they are successfully synchronized.

[0065] When it is detected that the synchronizer and the reverse gear are not synchronized and the oil temperature is lower than the preset temperature, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0066] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0067] In some optional embodiments, the preset forward gear corresponding to the preset forward gear is an even number of gears.

[0068] The reverse gear control method for dual-clutch transmissions provided in this application, where the reverse gear and a preset forward gear share a synchronizer, detects that the synchronizer and the reverse gear are not synchronized successfully, i.e., the reverse gear cannot be engaged. The synchronizer is then controlled to move in the opposite direction, first synchronizing with the preset forward gear, thus fine-tuning the synchronizer's position. Then, the connection between the synchronizer and the preset forward gear is disconnected, and an attempt is made to synchronize the synchronizer and the reverse gear again. Because the preset forward gear corresponding to the reverse gear is used to fine-tune the synchronizer's position first, the success rate of synchronizing the synchronizer and the reverse gear is increased, thus improving the success rate of engaging reverse gear.

[0069] This application also provides another method for controlling the reverse gear of a dual-clutch transmission, which is implemented by the transmission controller, such as... Figure 2 As shown, the method includes steps S201, S202, S203, S204, and S205, wherein:

[0070] In step S201, when a reverse gear engagement command is received, the synchronizer is controlled to move toward the reverse gear, and the synchronizer and the reverse gear are monitored to see if they are successfully synchronized.

[0071] In some optional embodiments, the preset forward gear corresponding to the preset forward gear is an even number of gears.

[0072] Therefore, the pre-set clutches for both forward and reverse gears are even-numbered clutches. When a reverse gear engagement command is received, the even-numbered clutches are engaged. Correspondingly, odd-numbered clutches are also provided for engaging 1st, 3rd, and 5th gears. Since most automatic transmission vehicles currently use a drive-by-wire system for gear shifting, the gear lever is not directly mechanically connected to the transmission's internal mechanisms. The driver's operation of the gear lever only triggers the shift command, rather than directly driving the transmission's internal mechanisms. After the shift command is triggered, the transmission controller receives the command and then controls the corresponding internal mechanisms to complete the shift. Specifically, when the transmission controller receives the reverse gear engagement command, it controls the synchronizer to move closer to the reverse gear and monitors whether the synchronizer and the reverse gear are successfully synchronized. Here, the synchronizer refers to the one used for reverse gear.

[0073] A synchronizer consists of a gear sleeve and a conical surface. The transmission controller controls the movement of the synchronizer by controlling the movement of the synchronizer's gear sleeve through a shift fork, thereby ultimately achieving engagement or disengagement with the gear of a specific gear.

[0074] Specifically, sensors can be used to determine whether the synchronizer and reverse gear are successfully synchronized. Position sensors can be used to determine if the synchronizer or reverse gear is rotating, thus determining whether they are successfully synchronized. Torque sensors can also be used to determine if the torque of the synchronizer, reverse gear, even-gear clutch, or engine has changed, thus determining whether they are successfully synchronized.

[0075] In step S202, when it is detected that the synchronizer and the reverse gear are not synchronized successfully, the number of synchronization failures is accumulated from zero, and it is determined whether the number of synchronization failures is greater than the preset number.

[0076] In some optional embodiments, the preset number of times can be 2.

[0077] When it is determined that the number of synchronization failures is not greater than the preset number, that is, when the judgment result of step S202 is "no", step S203 is executed, controlling the synchronizer to first separate from the reverse gear and then move towards the reverse gear again. Then, steps S201 and S202 are repeated again to monitor whether the synchronizer and the reverse gear are successfully synchronized. When it is detected that the synchronizer and the reverse gear are not successfully synchronized, the number of synchronization failures is accumulated from zero, and it is determined whether the number of synchronization failures is greater than the preset number.

[0078] Understandably, since friction is established between the synchronizer's conical surface and the reverse gear each time the synchronizer attempts to synchronize with the reverse gear, the relative position between the synchronizer and the reverse gear can be changed. Therefore, even if the synchronizer fails to synchronize with the reverse gear the first time, the relative position between the synchronizer and the reverse gear still changes, and the relative position will change towards synchronization. In this case, the synchronizer can be controlled to first separate from the reverse gear and then move towards the reverse gear again. Even if the synchronizer and the reverse gear attempt to synchronize again, there is a certain chance that the synchronizer will successfully synchronize with the reverse gear on the second attempt.

[0079] When it is determined that the number of synchronization failures is greater than the preset number, that is, when the judgment result of step S202 is "yes", step S204 is executed to control the synchronizer to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other.

[0080] The preset forward gear and reverse gear share a synchronizer, with the preset forward gear and reverse gear located at opposite ends of the synchronizer.

[0081] The preset forward gear can be 4.

[0082] Understandably, if the synchronizer and reverse gear fail to synchronize twice, it indicates that the relative positional difference between them may be too large. Due to the specific gear ratio of the reverse gear, the shifting force required to engage reverse is also relatively high. A single-cone synchronizer can provide relatively low synchronizing torque, especially at low temperatures and with low lubricating oil viscosity. In such cases, the synchronizing torque may be insufficient to synchronize the large relative positional difference between the synchronizer and the reverse gear, causing jamming and preventing engagement of reverse. Due to the special structure of a dual-clutch transmission, the reverse gear shares a synchronizer with the preset forward gears. The preset forward gears are located at opposite ends of the synchronizer, and the preset forward gears can be 2nd, 4th, or 6th gear. Because the gear ratios of 2nd, 4th, or 6th gears are different from those of reverse gear, the shifting force required to engage 2nd, 4th, or 6th gear is relatively smaller than that required to engage reverse gear. Therefore, when reverse gear cannot be engaged, the synchronizer is controlled to move away from the reverse gear and towards the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. That is, the preset forward gear that shares a synchronizer with reverse gear is engaged first, which causes the synchronizer to rotate and adjust its position.

[0083] In step S205, the connection between the synchronizer and the preset forward gear is disconnected, and the synchronizer is controlled to move towards the reverse gear so that the synchronizer and the reverse gear are synchronized.

[0084] Understandably, when reverse gear cannot be engaged, the synchronizer first moves away from the reverse gear and towards the preset forward gear, synchronizing with it. This involves engaging the preset forward gear that shares a synchronizer with reverse, causing the synchronizer to rotate and adjust its position. After using the preset forward gear that shares a synchronizer with reverse to rotate and adjust its position, the synchronizer is highly likely to match the position of the reverse gear, thus achieving successful synchronization.

[0085] Understandably, if the synchronizer and reverse gear are still not synchronized after step S205, you can re-execute the operation of first engaging a preset forward gear that shares a synchronizer with reverse gear, and then try engaging reverse gear.

[0086] In some optional embodiments, after disconnecting the synchronizer from the preset forward gear and controlling the synchronizer to move towards the reverse gear, the method further includes:

[0087] Monitor whether the synchronizer and reverse gear are successfully synchronized.

[0088] When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0089] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0090] It is understood that the reverse gear control method for dual-clutch transmissions provided in this application is mainly used to solve the problem of failing to engage reverse gear when the temperature is low and the lubricating oil viscosity is low. However, if the problem of failing to engage reverse gear still occurs when the temperature and lubricating oil viscosity are normal, it indicates that there may be other problems with the transmission. Therefore, in order to accurately locate the situation of low temperature and low lubricating oil viscosity, in some optional embodiments, the method further includes:

[0091] When a command to engage reverse gear is received, the synchronizer is controlled to move closer to the reverse gear, and the synchronizer and the reverse gear are monitored to ensure that they are successfully synchronized.

[0092] When it is detected that the synchronizer and the reverse gear are not synchronized and the oil temperature is lower than the preset temperature, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The preset forward gear and the reverse gear share a synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer.

[0093] Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

[0094] The reverse gear control method for dual-clutch transmissions provided in this application, when a synchronizer is shared between the reverse gear and a preset forward gear, if the synchronizer is not successfully synchronized with the reverse gear (i.e., the reverse gear fails to engage), the synchronizer is controlled to move in the opposite direction. This allows the synchronizer to first synchronize with the preset forward gear, thus fine-tuning the synchronizer's position. Then, the connection between the synchronizer and the preset forward gear is disconnected, and an attempt is made to synchronize the synchronizer with the reverse gear again. Because the position of the synchronizer is first fine-tuned using the preset forward gear corresponding to the reverse gear, the success rate of synchronizing the synchronizer with the reverse gear is increased, thus improving the success rate of engaging reverse gear.

[0095] This application also provides a vehicle, such as... Figure 3 As shown, the vehicle includes an odd-gear clutch 1, an even-gear clutch 2, a reverse gear 3, a synchronizer 4, and a preset forward gear 5. The vehicle also includes an engine 6, wheels 7, and a transmission controller, wherein the transmission controller is configured as follows:

[0096] When a command to engage reverse gear is received, the synchronizer 4 is controlled to move toward the reverse gear 3, and the synchronizer 4 and the reverse gear 3 are monitored to see if they are successfully synchronized.

[0097] In some optional embodiments, the preset forward gear 5 corresponds to an even-numbered forward gear.

[0098] Therefore, the pre-set forward and reverse gears are both even-numbered clutches (2). When a reverse gear engagement command is received, even-numbered clutches (2) are engaged. Correspondingly, odd-numbered clutches (1) are also provided for engaging 1st, 3rd, and 5th gears.

[0099] Because most automatic transmission vehicles currently use a drive-by-wire system for gear shifting, the gear lever and the mechanical structure within the transmission are not directly mechanically connected. The driver's operation of the gear lever only triggers the shift command, rather than directly driving the mechanical structure within the transmission. After the shift command is triggered, the transmission controller receives the command and then controls the corresponding mechanical structure within the transmission to complete the shift. Specifically, when the transmission controller receives the command to engage reverse gear, it controls synchronizer 4 to move closer to the reverse gear 3 and monitors whether synchronizer 4 and reverse gear 3 are successfully synchronized. Here, synchronizer 4 refers to the synchronizer used for reverse gear.

[0100] Synchronizer 4 includes a toothed sleeve and a conical surface. The transmission controller controls the movement of synchronizer 4 by controlling the movement of the toothed sleeve of synchronizer 4 through a shift fork, thereby ultimately achieving engagement or disengagement with the gear of a specific gear.

[0101] Specifically, sensors can be used to determine whether synchronizer 4 and reverse gear 3 are successfully synchronized. A position sensor can be used to determine whether synchronizer 4 or reverse gear 3 has rotated, thus determining whether they are successfully synchronized. A torque sensor can also be used to determine whether the torque of synchronizer 4, reverse gear 3, even-gear clutch 2, or the engine has changed, thus determining whether synchronizer 4 and reverse gear 3 are successfully synchronized.

[0102] When it is detected that synchronizer 4 and reverse gear 3 are not synchronized, synchronizer 4 is controlled to move away from reverse gear 3 and towards the preset forward gear 5, so that synchronizer 4 and the preset forward gear 5 are synchronized (e.g., Figure 4 As shown), the preset forward gear 5 and reverse gear 3 share a synchronizer 4, and the preset forward gear 5 and reverse gear 3 are located at opposite ends of the synchronizer 4.

[0103] Disconnect the synchronizer 4 from the preset forward gear 5, and control the synchronizer 4 to move closer to the reverse gear 3, so that the synchronizer 4 and the reverse gear 3 are synchronized (e.g., Figure 5 (As shown).

[0104] In some optional embodiments, the transmission controller is also configured to:

[0105] When it is detected that synchronizer 4 and reverse gear 3 are not synchronized, the number of synchronization failures is accumulated from zero, and it is determined whether the number of synchronization failures is greater than the preset number.

[0106] In some optional embodiments, the preset number of times can be 2.

[0107] When it is determined that the number of synchronization failures is not greater than the preset number, the synchronizer 4 is first separated from the reverse gear 3, and then moves towards the reverse gear 3 again.

[0108] Understandably, since friction is established between the synchronizer 4 and the reverse gear 3 each time the synchronizer 4 attempts to synchronize with the reverse gear 3, the relative position between the synchronizer 4 and the reverse gear 3 can be changed. Therefore, even if the synchronizer 4 and the reverse gear 3 fail to synchronize on the first attempt, the relative position between the synchronizer 4 and the reverse gear 3 still changes, and the relative position will change towards synchronization. In this case, the synchronizer 4 can be controlled to first separate from the reverse gear 3 and then move towards the reverse gear 3 again. Even if the synchronizer 4 and the reverse gear 3 attempt to synchronize again, there is a certain chance that the synchronizer 4 and the reverse gear 3 will be successfully synchronized on the second attempt.

[0109] When it is determined that the number of synchronization failures is greater than the preset number, the synchronizer 4 is controlled to move away from the reverse gear 3 and closer to the preset forward gear 5, so that the synchronizer 4 and the preset forward gear 5 are synchronized with each other. The connection between the synchronizer 4 and the preset forward gear 5 is disconnected, and the synchronizer 4 is controlled to move closer to the reverse gear 3, so that the synchronizer 4 and the reverse gear 3 are synchronized with each other.

[0110] The preset forward gear can be 4.

[0111] Understandably, if synchronizer 4 and reverse gear 3 fail to synchronize twice, it indicates that the relative positional difference between synchronizer 4 and reverse gear 3 may be too large. Due to the special gear ratio of reverse gear 3, the shifting force required to engage reverse is also relatively large. The single-cone structure of synchronizer 4 provides relatively small synchronizing torque, especially at low temperatures and with low lubricating oil viscosity. The synchronizing torque provided by synchronizer 4 may be insufficient to synchronize the large relative positional difference between synchronizer 4 and reverse gear 3, resulting in jamming and inability to engage reverse. Due to the special structure of a dual-clutch transmission, reverse gear 3 shares a synchronizer 4 with the preset forward gear 5. The preset forward gear 5 and reverse gear 3 are located at opposite ends of synchronizer 4, and the preset forward gear can be 2nd, 4th, or 6th gear. Because the gear ratios of 2nd, 4th, or 6th gears are different from those of reverse gear 3, the shifting force required to engage 2nd, 4th, or 6th gears is relatively smaller than that required to engage reverse gear. Therefore, when reverse gear cannot be engaged, the synchronizer 4 is controlled to move away from the reverse gear 3 and closer to the preset forward gear 5, so that the synchronizer 4 and the preset forward gear 5 are synchronized with each other. That is, the preset forward gear of the synchronizer 4 is first engaged, which shares the same synchronizer 4 as reverse gear, thereby enabling the synchronizer 4 to rotate and adjust its position.

[0112] Furthermore, by using the preset forward gear 5, which shares a preset forward gear position with the reverse gear 4, to make the synchronizer 4 rotate, and after adjusting the position of the synchronizer 4, the synchronizer 4 can most likely match the position of the reverse gear 3, so that the synchronizer 4 and the reverse gear 3 can be successfully synchronized with each other.

[0113] Understandably, if the synchronizer 4 is rotated by using the preset forward gear 5 that shares a synchronizer 4 with the reverse gear, the position of the synchronizer 4 is adjusted, and an attempt is made to synchronize the synchronizer 4 with the reverse gear 3, but synchronization between the synchronizer 4 and the reverse gear 3 is still not successfully achieved, then the operation of first engaging the preset forward gear that shares a synchronizer 4 with the reverse gear and then trying to engage the reverse gear can be performed again.

[0114] In some optional embodiments, the transmission controller is also configured to:

[0115] After disconnecting the synchronizer 4 from the preset forward gear 5 and controlling the synchronizer 4 to move closer to the reverse gear 3, monitor whether the synchronizer 4 and the reverse gear 3 are successfully synchronized.

[0116] When it is detected that synchronizer 4 and reverse gear 3 are not synchronized, synchronizer 4 is controlled to move away from reverse gear 3 and closer to preset forward gear 5, so that synchronizer 4 and preset forward gear 5 are synchronized with each other. Preset forward gear 5 and reverse gear 3 share a synchronizer 4, and preset forward gear 5 and reverse gear 3 are located at opposite ends of synchronizer 4.

[0117] Disconnect the synchronizer 4 from the preset forward gear 5, and control the synchronizer 4 to move closer to the reverse gear 3, so that the synchronizer 4 and the reverse gear 3 are synchronized.

[0118] In some optional embodiments, the transmission controller is also configured to:

[0119] When a command to engage reverse gear is received, the synchronizer 4 is controlled to move toward the reverse gear 3, and the synchronizer 4 and the reverse gear 3 are monitored to see if they are successfully synchronized.

[0120] When it is detected that synchronizer 4 and reverse gear 3 are not synchronized, and the oil temperature is lower than the preset temperature, synchronizer 4 is controlled to move away from reverse gear 3 and closer to the preset forward gear 5, so that synchronizer 4 and preset forward gear 5 are synchronized with each other. Preset forward gear 5 and reverse gear 3 share a synchronizer 4, and preset forward gear 5 and reverse gear 3 are located at opposite ends of synchronizer 4.

[0121] Disconnect the synchronizer 4 from the preset forward gear 5, and control the synchronizer 4 to move closer to the reverse gear 3, so that the synchronizer 4 and the reverse gear 3 are synchronized.

[0122] When using the vehicle provided in this application, if a synchronizer 4 is shared between the reverse gear and a preset forward gear, and it is detected that the synchronizer 4 and the reverse gear 3 are not successfully synchronized (i.e., the reverse gear cannot be engaged), the synchronizer 4 is controlled to move in the opposite direction. This allows the synchronizer 4 to first synchronize with the preset forward gear 5, thereby fine-tuning the position of the synchronizer 4. Then, the connection between the synchronizer 4 and the preset forward gear 5 is disconnected, and an attempt is made to synchronize the synchronizer 4 and the reverse gear 3 again. Because the position of the synchronizer 4 is fine-tuned first using the preset forward gear 5 corresponding to the reverse gear 3, the success rate of synchronizing the synchronizer 4 and the reverse gear 3 is increased, thus improving the success rate of engaging the reverse gear.

[0123] In this application, it should be understood that the terms “first”, “second”, etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.

[0124] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only.

[0125] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

[0126] The above description is only for the purpose of enabling those skilled in the art to understand the technical solution of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for controlling reverse gear in a dual-clutch transmission, characterized in that, The method includes: When a command to engage reverse gear is received, the synchronizer is controlled to move toward the reverse gear, and the synchronizer and the reverse gear are monitored to see if they are successfully synchronized. When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share one synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer. Disconnect the synchronizer from the preset forward gear, and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized. The method further includes: When it is detected that the synchronizer and the reverse gear are not synchronized successfully, the number of synchronization failures is accumulated starting from zero, and it is determined whether the number of synchronization failures is greater than a preset number; When it is determined that the number of synchronization failures is not greater than the preset number, the synchronizer is controlled to first separate from the reverse gear and then move towards the reverse gear again. When it is determined that the number of synchronization failures is greater than the preset number, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The connection between the synchronizer and the preset forward gear is disconnected, and the synchronizer is controlled to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

2. The reverse gear control method for a dual-clutch transmission according to claim 1, characterized in that, After disconnecting the synchronizer from the preset forward gear and controlling the synchronizer to move towards the reverse gear, the method further includes: Monitor whether the synchronizer and the reverse gear are successfully synchronized; When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share one synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer. Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

3. The reverse gear control method for a dual-clutch transmission according to claim 1, characterized in that, The method further includes: When a command to engage reverse gear is received, the synchronizer is controlled to move toward the reverse gear, and the synchronizer and the reverse gear are monitored to see if they are successfully synchronized. When it is detected that the synchronizer and the reverse gear are not synchronized successfully, and the oil temperature is lower than the preset temperature, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share one synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer. Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

4. The reverse gear control method for a dual-clutch transmission according to claim 1, characterized in that, The preset forward gear corresponds to an even-numbered forward gear.

5. A vehicle, characterized in that, The vehicle includes a transmission controller, a synchronizer, a reverse gear, and a preset forward gear. The transmission controller is configured to: When a reverse gear engagement command is received, the synchronizer is controlled to move toward the reverse gear, and the synchronizer and the reverse gear are monitored to see if they are successfully synchronized. When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share one synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer. Disconnect the synchronizer from the preset forward gear, and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized. The transmission controller is also configured to: When it is detected that the synchronizer and the reverse gear are not synchronized successfully, the number of synchronization failures is accumulated starting from zero, and it is determined whether the number of synchronization failures is greater than a preset number; When it is determined that the number of synchronization failures is not greater than the preset number, the synchronizer is controlled to first separate from the reverse gear and then move towards the reverse gear again. When it is determined that the number of synchronization failures is greater than the preset number, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized. The connection between the synchronizer and the preset forward gear is disconnected, and the synchronizer is controlled to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

6. The vehicle according to claim 5, characterized in that, The transmission controller is also configured to: After disconnecting the synchronizer from the preset forward gear and controlling the synchronizer to move closer to the reverse gear, monitor whether the synchronizer and the reverse gear are successfully synchronized. When it is detected that the synchronizer and the reverse gear are not synchronized, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share one synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer. Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

7. The vehicle according to claim 5, characterized in that, The transmission controller is also configured to: When a command to engage reverse gear is received, the synchronizer is controlled to move toward the reverse gear, and the synchronizer and the reverse gear are monitored to see if they are successfully synchronized. When it is detected that the synchronizer and the reverse gear are not synchronized successfully, and the oil temperature is lower than the preset temperature, the synchronizer is controlled to move away from the reverse gear and closer to the preset forward gear, so that the synchronizer and the preset forward gear are synchronized with each other. The preset forward gear and the reverse gear share one synchronizer, and the preset forward gear and the reverse gear are located at opposite ends of the synchronizer. Disconnect the synchronizer from the preset forward gear and control the synchronizer to move closer to the reverse gear, so that the synchronizer and the reverse gear are synchronized.

8. The vehicle according to claim 5, characterized in that, The preset forward gear corresponds to an even-numbered forward gear.

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