Shift control method, device, system, controller and storage medium

Abstract

The application discloses a gear shifting control method, device, system, controller and storage medium, to solve the technical problem that the existing gear bypass scheme may cause power interruption during gear shifting. The method part includes: when detecting a downshift demand from the current gear to the first gear, oiling the odd shaft clutch corresponding to the second gear; changing the input torque of the transmission from the even shaft to the odd shaft; controlling the engine speed to rise from the clutch speed corresponding to the current gear to the clutch speed corresponding to the second gear, and unloading the even clutch; after the even clutch completes unloading, controlling the first gear to perform fork gear engagement; after the fork gear engagement of the first gear is completed, oiling the even clutch; when detecting that the engine speed control is completed and the even clutch oiling is completed, exchanging the torque of the second gear and the first gear to switch to the first gear.

Description

Technical Field

[0001] This application relates to the field of vehicle gear shifting technology, and in particular to a gear shifting control method, device, system, controller, and storage medium. Background Technology

[0002] Currently, there is a trend towards higher gears in transmissions. Traditional dual-clutch transmissions require more space for layout. Considering the space constraints, gear reversal can achieve more gears within the same layout space by reusing gears. Therefore, gear reversal is a good solution for higher gears in transmissions.

[0003] The inventors discovered that the traditional solution directly uses a power interruption shift control method, which results in a power interruption during shifting. In order to avoid severe shocks during shifting, the conditions for using the bypass gear must be restricted, that is, the gear can only be shifted into when the input torque is relatively small. This severely limits the frequency of using the bypass gear, and thus seriously affects the economy of the transmission. Summary of the Invention

[0004] This application provides a shift control method, device, system, controller, and storage medium to solve the technical problem that existing gear shifting schemes can cause power interruption during gear shifting.

[0005] A shift control method, comprising:

[0006] When a downshifting requirement to coast from the current gear to the first gear is detected, the odd-numbered shaft clutch corresponding to the second gear is filled with oil. The first gear is the next gear after the current gear, and the second gear is the next gear after the first gear.

[0007] Once the odd-numbered shaft clutch is detected to be filled with oil to the target engagement point, the input torque of the transmission is switched from the even-numbered shaft to the odd-numbered shaft.

[0008] After the transmission input torque is switched from the even-numbered shaft to the odd-numbered shaft, the engine speed is controlled to increase from the clutch speed corresponding to the current gear to the clutch speed corresponding to the second gear, and the even-numbered clutch is unloaded.

[0009] After the even-numbered clutches have finished unloading oil, the first gear is controlled to engage the shift fork.

[0010] After the shift fork is engaged in the first gear, the even-numbered clutch is filled with oil.

[0011] When it is detected that the engine speed adjustment is completed and the even-numbered clutch is fully charged, the torque is exchanged between the second gear and the first gear to switch to the first gear.

[0012] In one embodiment, the step of filling the odd-numbered shaft clutch corresponding to the second gear with oil includes:

[0013] Fill the odd-numbered shaft clutch corresponding to the second gear with oil until it is half-engaged.

[0014] In one embodiment, the conversion of the transmission's input torque from an even-numbered axis to an odd-numbered axis includes:

[0015] The pressure of the even-numbered clutches is reduced to the half-engagement point at a certain slope.

[0016] The pressure of the odd-numbered clutch is increased from the half-engagement point at a certain slope to the target pressure point, so as to transfer the input torque of the transmission from the even-numbered shaft to the odd-numbered shaft.

[0017] In one embodiment, controlling the engine speed to increase from the clutch speed corresponding to the current gear to the clutch speed corresponding to the second gear includes:

[0018] A target engine speed curve is preset for coasting down from the current gear to the first gear;

[0019] By adjusting the clutch pressure of the second gear in a closed loop, the engine speed changes according to the engine target speed curve, thereby increasing the engine speed from the clutch speed corresponding to the current gear to the clutch speed corresponding to the first gear.

[0020] In one embodiment, after exchanging torque between the second gear and the first gear, the method further includes:

[0021] Release the clutch oil pressure on the odd-numbered shaft corresponding to the second gear.

[0022] In one embodiment, the method further includes:

[0023] When the vehicle experiences a power downshift from the current gear to the second gear, the engine speed is adjusted and the odd-numbered clutches are filled with oil.

[0024] When the engine speed reaches the clutch speed corresponding to the second gear, and the odd-numbered shaft clutch is fully lubricated, the open-loop control torque exchange control between the current gear and the second gear is applied to switch from the current gear to the second gear.

[0025] In one embodiment, the method further includes:

[0026] When the vehicle experiences a power downshift from the current gear to the target gear, torque control is applied to the odd-numbered shaft clutch and the even-numbered shaft clutch, and the engine speed is controlled to run at the target speed, where the target gear is the gear below the second gear.

[0027] Once it is detected that the two odd-numbered shaft clutches and the even-numbered shaft clutches have completed torque control and the engine speed has been adjusted, the current gear is disengaged and the target gear is engaged.

[0028] A controller includes a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the computer program, implements the steps of the shift control method as described in any of the preceding claims.

[0029] A shift control system, characterized in that it includes a controller as described above.

[0030] A readable storage medium storing a computer program, characterized in that, when executed by a processor, the computer program implements the steps of the shift control method as described in any of the preceding claims.

[0031] In one of the solutions provided above, the inventors specifically proposed a shift control method to address the gear shifting issue under the gear shifting bypass scheme. For example, when downshifting from 9th to 8th gear, since both 8th and 9th gears are located on even-numbered axes, a direct, uninterrupted shift from 9th to 8th gear cannot be achieved. The inventors discovered that to achieve a shift without power interruption, a transition gear is needed to facilitate the gear shift. Considering that engaging 9th gear requires 7th gear to be in gear simultaneously, the shifting bypass during the 9th to 8th gear downshift can be achieved using 7th gear. For power downshifting from 9th gear, a 7th gear bypass scheme is used to solve the 9th gear power downshifting problem. That is, when a power downshifting demand arises, the final target gear is engaged through a 7th gear shift, leading to 8th gear. For example, when shifting from 9th to 6th gear, the shift is first initiated through a 7th gear shift. Once 7th gear carries the torque, speed and torque adjustment begin, and through torque closed-loop control, the gear ultimately enters 6th gear. This method enables shifting without power interruption, thus avoiding severe shocks. On the other hand, by avoiding severe shocks, it can also increase the frequency of use of reused gears and improve the economy of the dual-clutch transmission. The following is a detailed description. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the 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.

[0033] Figure 1 This is a schematic flowchart of a shift control method in one embodiment of this application;

[0034] Figure 2 This is a schematic diagram of the gear shifting process from the current gear (9) to the first gear (8) in one embodiment of this application;

[0035] Figure 3 This is another schematic flowchart of the shift control method in one embodiment of this application;

[0036] Figure 4 This is a schematic diagram of the gear shifting process in one embodiment of this application, from the current gear (9) down to the second gear (7) and from the current gear (9) down to the target gear (6);

[0037] Figure 5 This is a schematic flowchart of a shift control method in one embodiment of this application;

[0038] Figure 6 This is a schematic diagram of the shift control device in one embodiment of this application;

[0039] Figure 7 This is a schematic diagram of a control structure in one embodiment of this application. Detailed Implementation

[0040] 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.

[0041] The shift control method provided in this application embodiment can be applied to a shift control system, wherein the shift control system includes a controller and a power system applied to a dual-clutch transmission. The controller may refer to a transmission control unit (TCU), or it may be an on-board controller such as a vehicle controller. This article uses a TCU as an example for illustration.

[0042] This powertrain includes odd-shaft clutches and even-shaft clutches. Currently, there is no proposed shift control method for dual-clutch transmissions with gear shifting that eliminates power interruption. Schemes that directly use power interruption shift control when the working gear (shifting gear) differs from the shifted gear by a certain number of gears will result in power interruption during shifting, severely impacting driving comfort and leading to a poorer user experience or even complaints. Furthermore, to avoid severe impacts, the use of the shifting gear will inevitably be restricted, only being used when torque is relatively low. This severely limits the frequency of gear reuse, thus significantly affecting the fuel economy of the dual-clutch transmission. Therefore, if this problem cannot be solved, high gears in the gear shifting scheme will become useless, and the gear shifting transmission configuration will be difficult to apply in actual production in the passenger vehicle sector.

[0043] The research revealed that the gear shifting scheme requires two gears (the shifting gear and the shifted gear) to be in operation simultaneously. Therefore, to avoid excessive clutch speed and vibration / noise issues caused by both gears being in operation at the same time, the gear ratios between the reused gears in the gear shifting scheme should not differ significantly. This means the constructed shifting gear and the shifted gear should be very close. Typically, for example, the gear ratio difference between the newly constructed shifting gear and the shifted gear is generally less than or equal to two gears. Considering that the shifting process between related gears becomes more complex after gear shifting, the gear shifting configurations of dual-clutch transmissions that can be mass-produced are usually for smaller or larger gears using the shifting scheme.

[0044] For example, suppose a dual-clutch transmission has a configuration where the 9th gear bypasses the 7th gear. That is, when the 7th gear is engaged, a multiplexer fork locks the two input shafts of the dual-clutch transmission, creating a new gear ratio on the other shaft – this is the 9th gear. This multiplexer fork can be combined with other gears to create other gear ratios, and thus other gears, which will not be elaborated here. From this, we can deduce that when the 9th gear fork is engaged, the 7th gear fork must also be in gear. Therefore, the 9th gear (actually a multiplexer fork, referred to as the 9th gear fork below) must be on a different shaft from the 7th gear, meaning the 9th gear fork is on an even-numbered shaft clutch.

[0045] Therefore, when there is a need to downshift from 9th to 8th gear while coasting, since both 8th and 9th gears are on the even-numbered shaft clutch (i.e., coaxial), using a power interruption shift at this time is only suitable when the transmission input torque is close to zero. If a situation with high negative torque occurs, a shift shock will occur, affecting driving comfort. Although traditional transmissions experience relatively few situations with high negative torque, and the shock problem can be mitigated by limiting the usage conditions of this gear, this leads to reduced fuel economy. This problem is particularly difficult to avoid when applied to hybrid transmissions, so a shift control method that can achieve power interruption must be invented.

[0046] When a downshift to 9th gear is required, traditional downshift control methods are no longer applicable because 9th gear is located on an even-numbered axis. A power interruption shift can be used, but this shift mode only works when the transmission input torque is close to zero. If the torque is high, a shift shock will occur, affecting driving comfort. Power downshifts typically involve relatively high torque, so a shift control method that can achieve seamless power interruption must be invented.

[0047] Based on the aforementioned technical problems, the inventors have proposed a shift control method to address the gear shifting problem under the gear shifting bypass scheme. For example, when downshifting from 9th to 8th gear, as mentioned earlier, since both 8th and 9th gears are located on even-numbered axes, a direct, uninterrupted shift from 9th to 8th gear cannot be achieved. The inventors discovered that to achieve a shift without power interruption, a transition gear is needed to connect the gears. Considering that engaging 9th gear requires 7th gear to be in gear simultaneously, the shifting bypass during the 9th to 8th gear downshift can be achieved using 7th gear. For power downshifting from 9th gear, a 7th gear bypass scheme is used to solve the 9th gear power downshifting problem. That is, when a power downshifting demand arises, the final target gear is engaged through a 7th gear shift, leading to 8th gear. For example, when shifting from 9th to 6th gear, the shift is first initiated through a 7th gear shift. Once 7th gear carries the torque, speed and torque adjustment begin, and through torque closed-loop control, the gear ultimately enters 6th gear. This method enables shifting without power interruption, thus avoiding severe shocks. On the other hand, by avoiding severe shocks, it can also increase the frequency of use of reused gears and improve the economy of the dual-clutch transmission. The following is a detailed description.

[0048] Before describing the specific implementation scheme of this application, it is worth noting that, considering some hybrid vehicles, the torque input to the transmission is actually the result of the coupling of the input torque of the motor and the engine. Therefore, the shift control method provided in this application is also suitable for hybrid vehicles with this configuration. For ease of description, the torque and speed at the transmission input end in the following text will be uniformly replaced by the torque and speed of the engine, without specific limitations.

[0049] In one embodiment, please refer to the following: Figure 1 and Figure 2As shown, a shift control method capable of achieving uninterrupted power transmission is provided. Taking the application of this method in a vehicle controller as an example, the method includes the following steps:

[0050] S10: When a downshifting requirement is detected to shift from the current gear (9) to the first gear (8), the odd-numbered shaft clutch corresponding to the second gear (7) is filled with oil;

[0051] Among them, the first gear (8) is the next gear after the current gear (9), the second gear (7) is the next gear after the first gear (8), and the current gear (9) is the construct gear of the second gear (7), that is, the current gear (9) is the bypass gear of the second gear (7).

[0052] It should be noted that, for the sake of easy reading of the scheme, the numbers marked after the current gear, first gear, and second gear are exemplary gears. For example, the current gear (9) represents the 9th gear, the first gear (8) represents the 8th gear, and the second gear (7) represents the 7th gear.

[0053] In this application, when the TCU detects that the current vehicle needs to downshift from the current gear (9) to the first gear (8) according to the shifting rules, it will perform the following shifting process. The shifting process can be divided into four stages according to its characteristics: clutch oil filling, torque exchange, engine speed adjustment and torque exchange. When adjusting the engine speed, it is necessary to unload oil from the even-numbered shaft, fill oil, and disengage the current gear (9) and engage the first gear (8) to complete the shifting.

[0054] For step S10, since the current gear (9) is in gear and the second gear (7) is also in gear, when a downshifting requirement is detected from the current gear (9) to the first gear (8), the clutch filling stage is carried out. The odd-numbered shaft clutch corresponding to the second gear (7) needs to be filled with oil to the target engagement point in order to prepare for the subsequent engagement of the second gear (7).

[0055] In one embodiment, step S10, namely, filling the odd-numbered shaft clutch corresponding to the second gear (7) with oil, specifically includes the following steps: filling the odd-numbered shaft clutch corresponding to the second gear (7) with oil until it reaches the half-engagement point, such as... Figure 2 As shown in the middle B stage, it is to prepare for the subsequent second gear (7) to engage in gear shifting, which is conducive to improving gear shifting efficiency.

[0056] S20: After detecting that the odd-numbered shaft clutch is filled with oil to the target engagement point, the input torque of the transmission is switched from the even-numbered shaft to the odd-numbered shaft.

[0057] When the TCU detects that the odd-numbered shaft clutch has finished filling with oil, it enters the torque exchange stage, that is, through the torque exchange of the second gear (7) and the first gear (8), the second gear (7) can carry the torque.

[0058] In one embodiment, step S20, which involves shifting the input torque of the transmission from the even-numbered axis to the odd-numbered axis, includes:

[0059] S21: Reduce the pressure of the even-numbered clutches to the half-engagement point at a certain slope;

[0060] S22: Increase the pressure of the odd-numbered clutch from the half-engagement point at a certain slope to the target pressure point, so as to achieve a complete switch of the transmission's input torque from the even-numbered shaft to the odd-numbered shaft.

[0061] For steps S21-S22, in specific implementation, the TCU reduces the pressure of the even-numbered clutches to the half-engagement point at a certain slope, while simultaneously increasing the pressure of the odd-numbered clutches from the half-engagement point to the target pressure point at a certain slope. This achieves a complete switch of the transmission's input torque from the even-numbered shaft to the odd-numbered shaft, i.e., through the torque exchange between the second gear (7) and the first gear (8), the second gear (7) carries the torque. During this process, it is necessary to intervene in the torque of the engine or motor to ensure that the vehicle does not experience a sudden change in acceleration during the torque exchange phase, such as... Figure 2 As shown in stage C.

[0062] S30: After the input torque of the transmission is changed from the even-numbered axis to the odd-numbered axis, the engine speed is controlled to be increased from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the second gear (7), and the even-numbered clutch is unloaded.

[0063] After the TCU completes the torque exchange phase, the engine speed adjustment phase begins. That is, after the TCU completes the transfer of the transmission input torque from the even-numbered axis to the odd-numbered axis, it controls the engine speed to increase from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the second gear (7). At the same time, the even-numbered clutch is unloaded.

[0064] S40: After the even-numbered clutches have finished unloading oil, control the first gear (8) to engage the shift fork;

[0065] S50: After the shift fork is engaged in the first gear (8), the even-numbered clutch is filled with oil;

[0066] In one embodiment, step S30, namely controlling the engine speed to increase from the clutch speed corresponding to the current gear to the clutch speed corresponding to the second gear, includes:

[0067] S31: Pre-set the engine target speed curve when coasting from the current gear (9) to the first gear (8);

[0068] S32: By adjusting the clutch pressure of the second gear (7) through closed-loop adjustment, the engine speed changes according to the engine target speed curve, so as to raise the engine speed from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the first gear (8).

[0069] Please see Figure 2 As shown in the DEFG stage, although the second gear (7) clutch is used for speed adjustment in this DEFG stage, the engine speed directly rises from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the first gear (8) to complete the speed adjustment.

[0070] While adjusting the engine speed, the even-numbered shaft clutches must first be unloaded. Figure 2 As shown in stage D, this prepares for subsequent gear shifting. After the even-numbered shaft clutch is unloaded, the even-numbered shaft can now perform gear shifting operations, disengaging the shift fork of the current gear (9) (as shown). Figure 2 As shown in the middle E stage), the shift fork (as shown in the middle E stage) is engaged in the first gear (8). Figure 2 (Middle F stage). After the first gear (8) shift fork is detected to be engaged, start filling the even-numbered clutch with oil (e.g. Figure 2 In the middle G stage, preparation is made for switching the torque to the first gear (8) later.

[0071] It is worth noting that in some implementations, torque intervention of the engine is also required throughout the speed adjustment phase to ensure the smoothness of the entire gear shifting process.

[0072] S60: When it is detected that the engine speed regulation is completed and the even-numbered clutch is filled with oil, the torque is exchanged between the second gear (7) and the first gear (8) to switch to the first gear (8).

[0073] Once the engine speed adjustment is detected as complete and the even-numbered clutches have finished filling with oil, the torque exchange between the second gear (7) and the first gear (8) begins, as follows: Figure 2 As shown in the H stage, it should be noted that in some schemes, the torque intervention on the engine needs to be canceled at the same time as the torque exchange.

[0074] If it is a hybrid transmission, it needs to be further processed according to the dotted lines in the diagram to further improve the smoothness of the entire shifting process. After the torque exchange is completed, the oil pressure of the odd-numbered shaft clutch corresponding to the second gear (7) is released, such as Figure 2As shown in stage I, the gear shift is now complete. The gear shifter slides from the current gear (9) to the first gear (8), achieving a power-free downshift. Then, the odd-numbered shaft disengages from the second gear (7) shift fork, as shown in stage I. Figure 2 As shown in stage A, the entire gear shifting process is complete.

[0075] It should be noted that the above-mentioned shift control embodiment of shifting from the current gear (9) to the first gear (8) without power interruption is specifically described using the example of coasting from 9th gear to 8th gear. In this application embodiment, a connection control embodiment of shifting from the current gear (9) to the second gear (7) and from the current gear (9) to the target gear (6th gear or other gear) is also provided, which will be described below.

[0076] In one embodiment, such as Figure 3 and Figure 4 As shown in the figure, this application embodiment also provides a gear shifting control method, including the following steps:

[0077] S101: When the vehicle has a power downshift requirement from the current gear (9) to the second gear (7), the engine speed is adjusted and the odd-numbered clutches are filled with oil.

[0078] When the TCU detects a downshift requirement in the current gear (9) of the vehicle based on the shift rules, it performs the following operations: First, it determines whether the gear to be downshifted is the second gear (7). If it is the second gear (7), since the current gear (9) is the construct of the second gear (7), the current gear (9) can be directly shifted to the second gear (7) without any overlap. If it is not equal to the second gear (7), the second gear (7) needs to be used for shift overlap control.

[0079] For the current gear (9) to second gear (7) operation, since the second gear (7) is also in gear when the current gear (9) is in gear, the gear shifting process can be divided into two stages: speed adjustment and torque exchange. If the required gear is another gear, the second gear (7) needs to be used for engagement. In this embodiment, when the vehicle has a power downshifting requirement from the current gear (9) to the second gear (7), the odd-numbered clutches are filled with oil while adjusting the speed, such as... Figure 4 As shown in stage B.

[0080] S102: When the engine speed reaches the clutch speed corresponding to the second gear (7) and the odd-numbered shaft clutch is fully charged, open-loop control torque exchange control is applied to the current gear (9) and the second gear (7) to switch from the current gear (9) to the second gear (7).

[0081] When the engine speed reaches the clutch speed of the second gear (7), and the odd-numbered shaft clutch is fully charged, the torque exchange stage begins, as follows: Figure 4As shown in stage D. In this stage D, if the required gear is the second gear (7), open-loop control is used for torque exchange control, such as... Figure 4 As shown by the solid line in the figure, after the torque exchange between the current gear (9) and the second gear (7) is completed, the current gear (9) is disengaged, the gear shift is completed, and the subsequent steps are exited.

[0082] It should be noted that the above-mentioned shift control embodiment for switching from the current gear (9) to the second gear (7) without power interruption is specifically described using the example of coasting from 9th gear to 7th gear. In this application embodiment, a connection control embodiment for the power downshift target (6 or other lower gear) of the current gear (9) is also provided, which will be described below.

[0083] In one embodiment, such as Figure 4 and Figure 5 As shown in the figure, this application embodiment also provides a gear shifting control method, including the following steps:

[0084] S201: When the vehicle has a power downshift requirement from the current gear (9) to the target gear (6), torque control is performed on the odd-numbered shaft clutch and the even-numbered shaft clutch, and the engine speed is controlled to run at the target speed.

[0085] The target gear is the gear below the second gear (7), that is, the target gear is 6th gear or the next gear, such as 5th gear or 4th gear. Here, we will take the target gear 6 as an example for explanation, without making any specific restrictions.

[0086] S202: After detecting that the two odd-numbered shaft clutches and the even-numbered shaft clutches have completed torque control and the engine speed has been adjusted, the current gear (9) is disengaged and the target gear (6) is engaged.

[0087] In this embodiment, if the second gear (7) is required, torque engagement control for the second gear (7) is necessary. At this time, the TCU uses speed and torque adjustment control, that is, by performing closed-loop torque control on the dual clutch, the engine speed is controlled to run at the target speed while torque is being exchanged. Figure 4 As shown by the dashed line.

[0088] Once the TCU detects that both clutches have completed speed and torque adjustment, it enters the speed adjustment phase. At this time, the TCU simultaneously performs gear shifting control, such as... Figure 4 During the process of shifting from the current gear (9) to the target gear (6), the operation of shifting from the current gear (9) to the target gear (6) is performed. Figure 4 As shown in the middle E stage.

[0089] As can be seen, the inventors have proposed a shift control method to address the issue of gear shifting using a gear detour scheme. For example, when downshifting from 9th to 8th gear, as mentioned earlier, since both 8th and 9th gears are located on even-numbered axes, a direct, uninterrupted shift from 9th to 8th gear cannot be achieved. The inventors discovered that to achieve a shift without power interruption, a transition gear is needed to facilitate the gear shift. Considering that engaging 9th gear requires 7th gear to be in gear simultaneously, the shift can be achieved using 7th gear. For power downshifting from 9th gear, a 7th gear detour scheme is used to solve the power downshifting problem. That is, when a power downshift is needed, the final target gear is engaged through a 7th gear detour, leading to 8th gear. Similarly, when shifting from 9th to 6th gear, the shift is first initiated through 7th gear. Once 7th gear carries the torque, speed and torque adjustment begin, and through torque closed-loop control, the gear ultimately enters 6th gear. This method enables shifting without power interruption, thus avoiding severe shocks. On the other hand, by avoiding severe shocks, the frequency of using reused gears can be increased, thereby improving the economy of the dual-clutch transmission.

[0090] It should be noted that the above examples are based on 9-speed, 8-speed, 7-speed and 6-speed gears, but do not limit this application. Other corresponding variations are within the scope of this application.

[0091] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0092] In one embodiment, a shift control device is provided, which corresponds one-to-one with the shift control methods described in the above embodiments. For ease of description, the shift control device will still be described here using 9-speed, 8-speed, 7-speed, and 6-speed as examples, without specific limitations. Figure 6 As shown, the shift control device includes a detection module 101 and a control module 102. Detailed descriptions of each functional module are as follows:

[0093] The control module 102 is used to fill the odd-numbered shaft clutch corresponding to the second gear (7) with oil when the detection module 101 detects a downshifting requirement from the current gear (9) to the first gear (8). The first gear (8) is the next gear after the current gear (9), and the second gear (7) is the next gear after the first gear (8). After the odd-numbered shaft clutch is filled with oil to the target engagement point, the input torque of the transmission is changed from the even-numbered shaft to the odd-numbered shaft.

[0094] The control module 102 is also used to control the engine speed to increase from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the second gear (7) after the detection module 101 detects that the input torque of the transmission has been changed from the even-numbered axis to the odd-numbered axis, and to unload the oil from the even-numbered clutch;

[0095] The control module 102 is also used to control the first gear (8) to engage the gear using the shift fork after the detection module 101 has finished unloading the oil from the even-numbered clutches.

[0096] The control module 102 is also used to fill the even-numbered clutch with oil after the detection module 101 completes the shifting of the fork in the first gear (8);

[0097] The control module 102 is also used to perform torque exchange between the second gear (7) and the first gear (8) when the detection module 101 detects that the engine speed adjustment is completed and the even-numbered clutch is filled with oil, so as to switch to the first gear (8).

[0098] In one embodiment, the control module 102 is specifically used to: fill the odd-numbered shaft clutch corresponding to the second gear (7) with oil to the half-engagement point.

[0099] In one embodiment, the control module 102 is specifically used for:

[0100] The pressure of the even-numbered clutches is reduced to the half-engagement point at a certain slope.

[0101] The pressure of the odd-numbered clutch is increased from the half-engagement point at a certain slope to the target pressure point, so as to transfer the input torque of the transmission from the even-numbered shaft to the odd-numbered shaft.

[0102] In one embodiment, the control module 102 is specifically used to: pre-set the engine target speed curve for coasting down from the current gear (9) to the first gear (8);

[0103] By adjusting the clutch pressure of the second gear (7) in a closed loop, the engine speed changes according to the engine target speed curve, so as to raise the engine speed from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the first gear (8).

[0104] In one embodiment, the control module 102 is specifically used to: after exchanging torque between the second gear (7) and the first gear, release the oil pressure of the odd-numbered shaft clutch corresponding to the second gear (7).

[0105] In one embodiment, the control module 102 is further configured to: adjust the engine speed and fill the odd-numbered clutch with oil when the detection module 101 detects that the current vehicle has a power downshift demand from the current gear (9) to the second gear (7); when the detection module 101 detects that the engine speed reaches the clutch speed corresponding to the second gear (7) and the odd-numbered shaft clutch is filled with oil, perform open-loop control torque exchange control on the current gear (9) and the second gear (7) to switch from the current gear (9) to the second gear (7).

[0106] In one embodiment, the control module 102 is further configured to: when the detection module 101 detects that the vehicle has a power downshift demand from the current gear (9) to the target gear, perform torque control on the odd-numbered shaft clutch and the even-numbered shaft clutch, and control the engine speed to run at the target speed, wherein the target gear is the lower gear of the second gear; when the detection module 101 detects that the two odd-numbered shaft clutches and the even-numbered shaft clutches have completed torque control and the engine speed has been adjusted, disengage the current gear (9) and engage the target gear (6).

[0107] Specific limitations regarding the shift control device can be found in the limitations of the shift control method described above, and will not be repeated here. Each module in the aforementioned shift control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of the controller in hardware form or independent of it, or stored in the memory of the controller in software form, so that the processor can call and execute the corresponding operations of each module.

[0108] In one embodiment, a controller is provided, which may be a transmission controller (TCU), and its internal structure diagram may be as follows: Figure 7 As shown. The controller includes a processor, memory, and network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores a computer program. The internal memory provides an environment for the execution of the computer program in the non-volatile storage medium. The network interface communicates with external systems or components via a network connection to obtain parameters / information required to implement this application. When the computer program is executed by the processor, it implements a gear shifting control method. More details of this gear shifting control method can be found in the description of the foregoing embodiments. Here, the controller is described using 9-speed, 8-speed, 7-speed, and 6-speed as examples, without further limitation.

[0109] In one embodiment, a controller is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to perform the following steps:

[0110] When a downshifting requirement is detected from the current gear (9) to the first gear (8), the odd-numbered shaft clutch corresponding to the second gear (7) is filled with oil. The first gear (8) is the next gear after the current gear (9), and the second gear (7) is the next gear after the first gear (8).

[0111] Once the odd-numbered shaft clutch is detected to be filled with oil to the target engagement point, the input torque of the transmission is switched from the even-numbered shaft to the odd-numbered shaft.

[0112] After the input torque of the transmission is switched from the even-numbered axis to the odd-numbered axis, the engine speed is controlled to be increased from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the second gear (7), and the even-numbered clutch is unloaded.

[0113] After the even-numbered clutches have finished unloading oil, the first gear (8) is controlled to engage the gear fork.

[0114] After the shift fork is engaged in the first gear (8), the even-numbered clutch is filled with oil.

[0115] When it is detected that the engine speed regulation is completed and the even-numbered clutch is filled with oil, the torque is exchanged between the second gear (7) and the first gear (8) to switch to the first gear (8).

[0116] In one embodiment, the processor, when executing the computer program, further performs the following steps:

[0117] Fill the odd-numbered shaft clutch corresponding to the second gear (7) with oil until it is half-engaged.

[0118] In one embodiment, the processor, when executing the computer program, further performs the following steps:

[0119] The pressure of the even-numbered clutches is reduced to the half-engagement point at a certain slope.

[0120] The pressure of the odd-numbered clutch is increased from the half-engagement point at a certain slope to the target pressure point, so as to transfer the input torque of the transmission from the even-numbered shaft to the odd-numbered shaft.

[0121] In one embodiment, the processor, when executing the computer program, further performs the following steps:

[0122] The engine target speed curve is preset to shift from the current gear (9) to the first gear (8);

[0123] By adjusting the clutch pressure of the second gear (7) in a closed loop, the engine speed changes according to the engine target speed curve, so as to raise the engine speed from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the first gear (8).

[0124] In one embodiment, the processor, when executing the computer program, further performs the following steps:

[0125] After exchanging torque between the second gear (7) and the first gear, the oil pressure of the odd-numbered shaft clutch corresponding to the second gear (7) is released.

[0126] In one embodiment, the processor, when executing the computer program, further performs the following steps:

[0127] When the vehicle has a power downshift requirement from the current gear (9) to the second gear (7), the engine speed is adjusted and the odd-numbered clutches are filled with oil.

[0128] When the engine speed reaches the clutch speed corresponding to the second gear (7) and the odd-numbered shaft clutch is fully charged, the open-loop control torque exchange control is applied to the current gear (9) and the second gear (7) to switch from the current gear (9) to the second gear (7).

[0129] In one embodiment, the processor, when executing the computer program, further performs the following steps:

[0130] When the vehicle has a power downshift requirement from the current gear (9) to the target gear, torque control is performed on the odd-numbered shaft clutch and the even-numbered shaft clutch, and the engine speed is controlled to run at the target speed. The target gear is the lower gear of the second gear.

[0131] After detecting that the two odd-numbered shaft clutches and the even-numbered shaft clutches have completed torque control and the engine speed has been adjusted, the current gear (9) is disengaged and the target gear (6) is engaged.

[0132] In one embodiment, a shift control system is provided, which includes the controller described in the foregoing embodiments. The functions or steps implemented by the controller can be referred to the description of the foregoing embodiments, and will not be repeated here.

[0133] In one embodiment, a vehicle is provided, which includes the controller described in the foregoing embodiments. The functions or steps implemented by the controller can be referred to the description of the foregoing embodiments, and will not be repeated here.

[0134] In one embodiment, a computer-readable storage medium is provided on which a computer program is stored. Here, the control is described using 9-speed, 8-speed, 7-speed, and 6-speed as examples, but the specific implementation is not limited. When the computer program is executed by a processor, it performs the following steps:

[0135] When a downshifting requirement is detected from the current gear (9) to the first gear (8), the odd-numbered shaft clutch corresponding to the second gear (7) is filled with oil. The first gear (8) is the next gear after the current gear (9), and the second gear (7) is the next gear after the first gear (8).

[0136] Once the odd-numbered shaft clutch is detected to be filled with oil to the target engagement point, the input torque of the transmission is switched from the even-numbered shaft to the odd-numbered shaft.

[0137] After the input torque of the transmission is switched from the even-numbered axis to the odd-numbered axis, the engine speed is controlled to be increased from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the second gear (7), and the even-numbered clutch is unloaded.

[0138] After the even-numbered clutches have finished unloading oil, the first gear (8) is controlled to engage the gear fork.

[0139] After the shift fork is engaged in the first gear (8), the even-numbered clutch is filled with oil.

[0140] When it is detected that the engine speed regulation is completed and the even-numbered clutch is filled with oil, the torque is exchanged between the second gear (7) and the first gear (8) to switch to the first gear (8).

[0141] In one embodiment, when the computer program is executed by the processor, it further performs the following steps:

[0142] Fill the odd-numbered shaft clutch corresponding to the second gear (7) with oil until it is half-engaged.

[0143] In one embodiment, when the computer program is executed by the processor, it further performs the following steps:

[0144] The pressure of the even-numbered clutches is reduced to the half-engagement point at a certain slope.

[0145] The pressure of the odd-numbered clutch is increased from the half-engagement point at a certain slope to the target pressure point, so as to transfer the input torque of the transmission from the even-numbered shaft to the odd-numbered shaft.

[0146] In one embodiment, when the computer program is executed by the processor, it further performs the following steps:

[0147] The engine target speed curve is preset to shift from the current gear (9) to the first gear (8);

[0148] By adjusting the clutch pressure of the second gear (7) in a closed loop, the engine speed changes according to the engine target speed curve, so as to raise the engine speed from the clutch speed corresponding to the current gear (9) to the clutch speed corresponding to the first gear (8).

[0149] In one embodiment, when the computer program is executed by the processor, it further performs the following steps:

[0150] After exchanging torque between the second gear (7) and the first gear, the oil pressure of the odd-numbered shaft clutch corresponding to the second gear (7) is released.

[0151] In one embodiment, when the computer program is executed by the processor, it further performs the following steps:

[0152] When the vehicle has a power downshift requirement from the current gear (9) to the second gear (7), the engine speed is adjusted and the odd-numbered clutches are filled with oil.

[0153] When the engine speed reaches the clutch speed corresponding to the second gear (7) and the odd-numbered shaft clutch is fully charged, the open-loop control torque exchange control is applied to the current gear (9) and the second gear (7) to switch from the current gear (9) to the second gear (7).

[0154] In one embodiment, when the computer program is executed by the processor, it further performs the following steps:

[0155] When the vehicle has a power downshift requirement from the current gear (9) to the target gear, torque control is performed on the odd-numbered shaft clutch and the even-numbered shaft clutch, and the engine speed is controlled to run at the target speed. The target gear is the lower gear of the second gear.

[0156] After detecting that the two odd-numbered shaft clutches and the even-numbered shaft clutches have completed torque control and the engine speed has been adjusted, the current gear (9) is disengaged and the target gear (6) is engaged.

[0157] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0158] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0159] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A gear shifting control method, characterized in that, The method is applied in a dual-clutch transmission, where the current gear is a second gear, and the current gear is coaxially arranged with the first gear. The method includes: When a downshifting requirement to coast from the current gear to the first gear is detected, the odd-numbered shaft clutch corresponding to the second gear is filled with oil. The first gear is the next gear after the current gear, and the second gear is the next gear after the first gear. Once the odd-numbered shaft clutch is detected to be filled with oil to the target engagement point, the input torque of the transmission is switched from the even-numbered shaft to the odd-numbered shaft. Control the engine speed to increase from the clutch speed corresponding to the current gear to the clutch speed corresponding to the second gear, and unload the oil from the even-numbered shaft clutch; After the even-numbered shaft clutch has finished unloading oil, control the first gear position to engage the shift fork. After the shift fork is engaged in the first gear, the even-numbered shaft clutch is filled with oil. When it is detected that the engine speed adjustment is completed and the even-numbered shaft clutch is fully charged, the torque is exchanged between the second gear and the first gear to switch to the first gear.

2. The shift control method as described in claim 1, characterized in that, The process of filling the odd-numbered shaft clutch corresponding to the second gear with oil includes: Fill the odd-numbered shaft clutch corresponding to the second gear with oil until it is half-engaged.

3. The shift control method as described in claim 1, characterized in that, The process of shifting the input torque of the transmission from the even-numbered axis to the odd-numbered axis includes: The pressure of the even-numbered shaft clutch is reduced to the half-engagement point at a certain slope. The pressure of the odd-numbered shaft clutch is increased from the half-engagement point at a certain slope to the target pressure point, so as to transfer the input torque of the transmission from the even-numbered shaft to the odd-numbered shaft.

4. The shift control method as described in claim 1, characterized in that, The control of increasing the engine speed from the clutch speed corresponding to the current gear to the clutch speed corresponding to the second gear includes: A target engine speed curve is preset for coasting down from the current gear to the first gear; By adjusting the clutch pressure of the second gear in a closed loop, the engine speed changes according to the engine target speed curve, thereby increasing the engine speed from the clutch speed corresponding to the current gear to the clutch speed corresponding to the first gear.

5. The shift control method as described in claim 1, characterized in that, After exchanging torque between the second gear and the first gear, the method further includes: Release the clutch oil pressure on the odd-numbered shaft corresponding to the second gear.

6. The shift control method according to any one of claims 1-5, characterized in that, The method further includes: When the vehicle experiences a power downshift from the current gear to the second gear, the engine speed is adjusted and the odd-numbered shaft clutch is filled with oil. When the engine speed reaches the clutch speed corresponding to the second gear, and the odd-numbered shaft clutch is fully lubricated, the open-loop control torque exchange control between the current gear and the second gear is applied to switch from the current gear to the second gear.

7. The shift control method according to any one of claims 1-5, characterized in that, The method further includes: When the vehicle experiences a power downshift from the current gear to the target gear, torque control is applied to the odd-numbered shaft clutch and the even-numbered shaft clutch, and the engine speed is controlled to run at the target speed, where the target gear is the gear below the second gear. Once it is detected that the two odd-numbered shaft clutches and the even-numbered shaft clutches have completed torque control and the engine speed has been adjusted, the current gear is disengaged and the target gear is engaged.

8. A controller comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the shift control method as described in any one of claims 1 to 7.

9. A shift control system, characterized in that, Includes the controller as described in claim 8.

10. A readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the shift control method as described in any one of claims 1 to 7.

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