Gear control method based on dog clutch and related device
By calculating the estimated synchronization time and controlling the combination time of the dog tooth clutch, the durability life problem of the dog tooth clutch caused by the lack of synchronized friction elements is solved, achieving a longer service life and a smoother combination process.
Patent Information
- Application Number
- CN202310885593.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-18
- Publication Date
- 2025-01-21
AI Technical Summary
Due to the lack of synchronous friction elements, the dog-tooth clutch cannot achieve friction control, which causes it to wear out when the speed difference cannot be eliminated, reducing its durability life.
By obtaining the actual speed and target speed of the turbine, calculate the estimated synchronization time. If the estimated synchronization time is less than or equal to the torque response delay time of the engine or the hydraulic control delay time of the dog tooth clutch, send a torque reduction request or open the control solenoid valve. , to control the engagement time of the dog clutch.
It effectively avoids the dog tooth clutch from combining near zero speed difference, reduces the load of the engine on the dog tooth clutch, extends the durability life of the dog tooth clutch, and ensures its smooth combination.
Smart Images
Figure CN119333559A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of vehicle control technology, and in particular to a gear control method based on a dog clutch and a related device. Background Art
[0002] Dog clutch is a common mechanical transmission device, mainly used to control the operation and stop of mechanical equipment. The master and slave ends of the dog clutch are splined, such as Figure 1 As shown, the dog clutch includes inner dog teeth and outer dog teeth.
[0003] Depend on Figure 1 It can be seen that the dog clutch has no synchronous friction element, which makes the dog clutch structure very simple and the space size very compact. However, it also causes the dog clutch to be unable to achieve sliding friction control, that is, the dog clutch itself has no speed regulation capability. During the dog clutch engagement process, if there is a speed difference between the two ends of the dog clutch, and the speed difference cannot be eliminated by sliding friction control, the dog clutch may be worn out, resulting in a short durability of the dog clutch. Summary of the invention
[0004] In view of the above problems, the present application provides a gear control method and related device based on a dog clutch, which are used to improve the durability of the dog clutch.
[0005] Based on this, the embodiments of the present application disclose the following technical solutions:
[0006] On the one hand, an embodiment of the present application provides a gear control method based on a dog clutch, the method comprising:
[0007] Acquiring an actual rotation speed of a turbine and a target rotation speed of the turbine;
[0008] If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, an estimated synchronization time is obtained, wherein the estimated synchronization time is used to identify the time required for the dog clutch to drop to zero at the current speed difference change rate, and the dog clutch is a clutch to be engaged;
[0009] If the estimated synchronization time is less than or equal to the torque response delay time of the engine, sending a torque reduction request for the engine;
[0010] If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened.
[0011] Optionally, the method further includes:
[0012] Acquiring an actual rotation speed of the turbine and a target rotation speed of the turbine;
[0013] The estimated synchronization time is calculated according to the actual speed of the turbine and the target speed of the turbine, and the calculation method is as follows:
[0014]
[0015] Wherein, SyncTm_Estd is the estimated synchronization time, TurbSpd is the actual speed of the turbine, and OncSpd is the target speed of the turbine.
[0016] Optionally, the method further includes:
[0017] If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the acceleration of the turbine is kept unchanged until the estimated synchronization time is less than or equal to the torque response delay time of the engine or the hydraulic control delay time of the dog clutch.
[0018] Optionally, maintaining the acceleration of the turbine unchanged comprises:
[0019] The torque of the off-going clutch is not increased in order to keep the acceleration of the turbine constant.
[0020] Optionally, the method further includes:
[0021] Reduce the torque of the off-going clutch;
[0022] If the torque of the engine is greater than the torque of the off-going clutch, the rotation speed of the engine is increased so that the off-going clutch enters a slipping state.
[0023] Optionally, after the to-be-released clutch enters a slipping state, the method further includes:
[0024] By controlling the pressure of the off-going clutch, the rotation speed of the turbine is increased toward a target rotation speed of the turbine based on a preset acceleration.
[0025] Optionally, the method further includes:
[0026] After the dog clutch has completed engagement, the torque request to the engine is removed and the off-going clutch is opened.
[0027] On the other hand, the present application provides a gear position control device based on a dog clutch, the device comprising: an acquisition unit and an execution unit;
[0028] The acquisition unit is used to acquire the actual rotation speed of the turbine and the target rotation speed of the turbine;
[0029] The acquisition unit is further configured to acquire an estimated synchronization time if a difference between an actual speed of the turbine and a target speed of the turbine is less than a preset speed difference, wherein the estimated synchronization time is used to identify a time required for the dog clutch to decrease to zero at a current speed difference change rate, the dog clutch being a clutch to be engaged;
[0030] the execution unit is configured to send a torque reduction request for the engine if the estimated synchronization time is less than or equal to a torque response delay time of the engine;
[0031] The execution unit is further configured to open the control solenoid valve of the dog clutch if the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch.
[0032] Optionally, the device further comprises a computing unit;
[0033] The acquisition unit is further used to acquire the actual rotation speed of the turbine and the target rotation speed of the turbine;
[0034] The calculation unit is used to calculate the estimated synchronization time according to the actual speed of the turbine and the target speed of the turbine, and the calculation method is as follows:
[0035]
[0036] Wherein, SyncTm_Estd is the estimated synchronization time, TurbSpd is the actual speed of the turbine, and OncSpd is the target speed of the turbine.
[0037] Optionally, the execution unit is further used for:
[0038] If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the acceleration of the turbine is kept unchanged until the estimated synchronization time is less than or equal to the torque response delay time of the engine or the hydraulic control delay time of the dog clutch.
[0039] Optionally, the execution unit is further used for:
[0040] The torque of the off-going clutch is not increased in order to keep the acceleration of the turbine constant.
[0041] Optionally, the execution unit is further used for:
[0042] Reducing the torque of the off-going clutch;
[0043] If the torque of the engine is greater than the torque of the off-going clutch, the rotation speed of the engine is increased so that the off-going clutch enters a slipping state.
[0044] Optionally, the execution unit is further used for:
[0045] After the off-going clutch enters the slipping state, the rotation speed of the turbine increases toward the target rotation speed of the turbine based on a preset acceleration by controlling the pressure of the off-going clutch.
[0046] Optionally, the execution unit is further used for:
[0047] After the dog clutch is engaged, the torque request to the engine is removed and the off-going clutch is opened.
[0048] In another aspect, the present application provides a computer device, the device comprising a processor and a memory:
[0049] The memory is used to store program code and transmit the program code to the processor;
[0050] The processor is used to execute the method described in the above aspects according to the instructions in the program code.
[0051] On the other hand, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method described in the above aspects.
[0052] On the other hand, an embodiment of the present application provides a computer program product or a computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the method described in the above aspects.
[0053] The advantages of the above technical solution of this application are:
[0054] The actual speed of the turbine and the target speed of the turbine are obtained. If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the synchronous control stage is entered to obtain the estimated synchronization time, which can identify the time required for the dog clutch to drop to zero at the current speed difference change rate. If the estimated synchronization time is less than or equal to the torque response delay time of the engine, a torque reduction request is sent to the engine so that the actual torque of the engine can reach the requested target torque when the speed difference of the dog clutch is near zero, so as to keep the actual transmission torque of the dog clutch less than the designed target torque during the engagement of the dog clutch, so as to avoid the short durability of the dog clutch due to the lack of synchronous friction elements. In addition, since the torque of the engine starts to decrease in advance, it is avoided that the engine transfers too much load to the dog clutch, thereby avoiding the dog clutch from being able to engage smoothly and affecting the performance of the dog clutch. If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened, that is, the control solenoid valve of the dog clutch is opened in advance, so that the dog clutch starts to engage when the speed difference is near zero, so as to avoid the short durability of the dog clutch due to the lack of synchronization friction elements. BRIEF DESCRIPTION OF THE DRAWINGS
[0055] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0056] Figure 1 A schematic diagram of a single-piece structure of a dog clutch;
[0057] Figure 2 A schematic diagram of a 9-speed automatic transmission structure;
[0058] Figure 3 For a Figure 2 Schematic diagram of the corresponding clutch engagement corresponding gear position;
[0059] Figure 4 A flow chart of a gear control method based on a dog clutch provided in an embodiment of the present application;
[0060] Figure 5 A schematic diagram of a scenario of a gear control method based on a dog clutch provided in an embodiment of the present application;
[0061] Figure 6A schematic diagram of a gear control device based on a dog clutch provided in an embodiment of the present application;
[0062] Figure 7 A structural diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION
[0063] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0064] As can be seen from the above, the dog clutch has no synchronous friction element, which makes the dog clutch structure very simple and the space size very compact. However, it also makes the dog clutch unable to achieve sliding friction control, that is, the dog clutch itself has no speed regulation capability. During the dog clutch engagement process, if there is a speed difference between the two ends of the dog clutch, since the dog clutch has no synchronous friction element, the speed difference cannot be eliminated by sliding friction control, which may wear out the dog clutch, resulting in a short durability of the dog clutch.
[0065] The following is an explanation using the Power Downshift (PD) control process as an example.
[0066] The working principle of the dog clutch is to achieve the purpose of transmission and disconnection through the engagement and separation of the dog teeth. Figure 2 , which is a schematic diagram of a 9-speed automatic transmission (9AT) structure. Taking dog tooth A as an example, the inner dog tooth is connected to the turbine input shaft and rotates with the turbine, and the outer dog tooth is connected to the sun gear of planetary gear 2 and rotates with the sun gear 2. The combination of dog tooth A realizes the mechanical connection between the sun gear 2 and the turbine shaft and rotates together.
[0067] exist Figure 2 In the 9AT, there are 4 planetary gears, which combine into 10 gears, 9 forward gears and one R gear. Each of the 10 gears of the 9AT needs to be combined with 3 clutches to form a fixed speed ratio. Among them, components A-component F are clutches, and components A and F are dog clutches. Figure 3 , the figure is a Figure 2 Schematic diagram of the corresponding clutch engagement corresponding gear position. Figure 3 In the example, the first forward gear requires the combination of element A, element F and element D.
[0068] If the PD control process involves a dog clutch, the dog clutch is generally an oncoming clutch, that is, a clutch waiting to be engaged during the gear shifting process. Figure 3 Taking the downshift from forward gear 5 to forward gear 4 as an example, it is necessary to change from clutch B, clutch E and dog clutch A to clutch E, dog clutch F and dog clutch A. In this process, the offgoing clutch is clutch B (the offgoing clutch is the clutch waiting to be separated during the gear shifting process), the engaged clutch is dog clutch F, and clutch E and dog clutch A are normally engaged clutches (the normally engaged clutch is the clutch that does not change during the gear shifting process).
[0069] In the PD control process based on the dog clutch, it is necessary to cooperate with the torque request to the engine through the clutch to be separated, that is, to adjust the engine speed based on the engine torque request, adjust the turbine speed based on the engine speed, and adjust the speed difference at both ends of the dog clutch based on the turbine speed, so as to achieve more precise control of the speed difference and its change rate at both ends of the dog clutch, which can not only improve the durability of the dog clutch, but also ensure the smooth engagement of the dog clutch.
[0070] Therefore, during the engagement of the dog clutch, the speed difference at both ends of the dog clutch cannot exceed the preset speed difference threshold to avoid affecting the durability of the dog clutch. At the same time, during the engagement of the dog clutch, the dog clutch cannot bear excessive load, which will cause the teeth to get stuck and affect the durability of the dog clutch. Therefore, during the engagement of the dog clutch, the following two control requirements must be met:
[0071] (1) The dog gear speed difference cannot exceed a preset speed difference threshold (SlpMax) so that the dog gear clutch can start to engage when the speed difference is 0, thereby avoiding a shorter durability life of the dog gear clutch due to the lack of a synchronous friction element.
[0072] (2) The load of the dog clutch cannot exceed the preset load threshold (TrqMax) to avoid the engine load being transferred to the dog clutch, causing the dog clutch to not engage smoothly and affecting the performance of the dog clutch.
[0073] Based on this, the embodiment of the present application provides a gear control method and related device based on a dog clutch, which obtains the actual speed of the turbine and the target speed of the turbine. If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the synchronous control stage is entered to obtain the estimated synchronization time, which can identify the time required for the dog clutch to drop to zero at the current speed difference change rate. If the estimated synchronization time is less than or equal to the torque response delay time of the engine, a torque reduction request for the engine is sent so that when the speed difference of the dog clutch is near zero, the actual torque of the engine can reach the requested target torque, so as to keep the actual transmission torque of the dog clutch less than the designed target torque during the dog clutch engagement process, so as to avoid the short durability of the dog clutch due to the lack of synchronous friction elements. In addition, since the torque of the engine starts to decrease in advance, it is avoided that the engine transfers too much load to the dog clutch, thereby avoiding the dog clutch from being able to engage smoothly and affecting the performance of the dog clutch. If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened, that is, the control solenoid valve of the dog clutch is opened in advance, so that the dog clutch starts to engage when the speed difference is near zero, so as to avoid the short durability of the dog clutch due to the lack of synchronization friction elements.
[0074] Combine the following Figure 4 , a gear control method based on a dog clutch provided in an embodiment of the present application is introduced. Figure 4 The method shown in the embodiment can be executed by an electronic control unit (ECU) included in a vehicle, for example. Figure 4 , this figure is a flow chart of a gear control method based on a dog clutch provided in an embodiment of the present application, and the method may include S401-S404.
[0075] S401: Acquire the actual speed of the turbine and the target speed of the turbine.
[0076] The actual speed of the turbine is the speed of the turbine during actual operation collected by the sensor. The target speed of the turbine is the speed that the turbine is expected to reach during operation. As a possible implementation, the output shaft speed of the transmission can be collected based on the sensor, and the target speed of the turbine can be obtained by multiplying the output shaft speed of the transmission by the speed ratio of the actual gear of the current vehicle. For example, if the current instruction is to downgrade from forward gear 5 to forward gear 4, then forward gear 5 is the current gear. It can be understood that forward gear 4 is the target gear.
[0077] S402: If the difference between the actual speed of the turbine and the target speed of the turbine is less than a preset speed difference, an estimated synchronization time is obtained.
[0078] If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the synchronous control stage (ie, the Sync stage) is entered.
[0079] In the related art, if the Sync stage is entered during the PD control process, the load of the engine, that is, the torque of the clutch to be separated, will be increased by increasing the pressure of the clutch to be separated. Thereby, the rising speed of the actual speed of the engine is reduced, and then the rising speed of the actual speed of the turbine is also slowed down. When the speed difference between the actual speed of the turbine and the target speed of the turbine is less than a certain value, the clutch to be engaged begins to engage, and the clutch to be separated is opened to complete the gear shift. However, a speed difference will be generated in this process. If the clutch to be engaged is a dog clutch, the dog clutch itself has no speed regulation capability, resulting in the speed difference being unable to be eliminated by sliding friction control, which may wear out the dog clutch, resulting in a shorter durability of the dog clutch.
[0080] Based on this, in the embodiment of the present application, after entering the Sync stage, the dog clutch is no longer engaged after the turbine acceleration is reduced, but the estimated synchronization time is obtained so as to engage the dog clutch at the appropriate time. The estimated synchronization time is used to identify the time required for the dog clutch to drop to zero at the current speed difference change rate, that is, the appropriate time refers to the speed difference of the dog clutch being near zero, thereby reducing the probability that the speed difference cannot be eliminated through slip control, resulting in a shortened durability of the dog clutch.
[0081] As a possible implementation method, since the estimated synchronization time refers to the time required for the dog clutch to drop to zero at the current speed difference change rate, if the current speed difference change rate changes, the estimated synchronization time will also change. The actual speed of the turbine and the target speed of the turbine can be obtained at fixed intervals or in real time, and the estimated synchronization time can be calculated based on the actual speed of the turbine and the target speed of the turbine. The calculation method can refer to the following formula:
[0082]
[0083] Among them, SyncTm_Estd is the estimated synchronization time, TurbSpd is the actual speed of the turbine, and OncSpd is the target speed of the turbine.
[0084] As a possible implementation method, since the estimated synchronization time refers to the time required for the dog clutch to drop to zero at the current speed difference change rate, if the current speed difference change rate changes, the estimated synchronization time will also change. In order to more accurately enable the dog clutch to start engaging when the speed difference of the dog clutch is near zero, the estimated synchronization time can be guaranteed to be more accurate. At this time, the acceleration of the turbine can be kept unchanged, that is, if the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the acceleration of the turbine is kept unchanged, that is, the acceleration of the turbine remains constant, so that the pressure of the clutch to be separated will not increase additionally, and the torque of the clutch to be separated will not increase, and it will remain stable, so as to improve the estimated accuracy of the estimated synchronization time, until the estimated synchronization time is less than or equal to the torque response delay time of the engine or the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch.
[0085] It can be understood that when the estimated synchronization time is less than or equal to the torque response delay time of the engine or the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the subsequent dog gear operation will be triggered, that is, the dog clutch will start to engage. At the same time, the engine will reduce the torque, so that the acceleration of the turbine will be reduced until the actual speed of the turbine is consistent with the target speed of the turbine.
[0086] The embodiment of the present application does not specifically limit the manner of maintaining the acceleration of the turbine unchanged. For example, the torque of the off-going clutch may not be increased in order to maintain the acceleration of the turbine unchanged.
[0087] S403: If the estimated synchronization time is less than or equal to the torque response delay time of the engine, a torque reduction request for the engine is sent.
[0088] If the estimated synchronization time is less than or equal to the torque response delay time of the engine, a torque reduction request for the engine is sent, that is, a torque reduction request for the engine is sent in advance, so that the actual torque of the engine can reach the requested target torque when the speed difference of the dog clutch is near zero, so as to ensure that the actual transmission torque of the dog clutch is less than the designed target torque during the engagement process of the dog clutch. Therefore, the engine will reduce the torque in advance based on the torque reduction request, so that the load of the engine is lower, and the engine is prevented from transmitting too much load to the dog clutch, that is, the load of the dog clutch will not exceed the preset load threshold, so as to avoid the dog clutch not being able to engage smoothly and affecting the performance of the dog clutch.
[0089] The speed difference of the dog clutch is zero, which is also the moment when the difference between the actual speed of the turbine and the target speed of the turbine is zero.
[0090] S404: If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened.
[0091] If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened, that is, the control solenoid valve of the dog clutch is opened in advance, so that the dog clutch starts to engage when the speed difference of the dog clutch is near zero. Therefore, when the speed difference of the dog clutch is very small, the dog clutch is engaged, which will not wear the dog clutch and avoid the reduction of the durability of the dog clutch.
[0092] In addition, based on the advance control of S403 and S404, the dog tooth speed difference will not exceed the preset speed difference threshold, so that the dog tooth clutch can start to engage when the speed difference is near 0, so that during the engagement of the dog tooth clutch, the actual transmission torque of the dog tooth clutch is less than the designed target torque, avoiding the short durability life of the dog tooth clutch due to the lack of synchronous friction elements.
[0093] It should be noted that the torque response delay time of the engine and the hydraulic control delay time of the dog clutch can be obtained through bench and actual vehicle test experiments.
[0094] It can be seen from the above technical solution that the actual speed of the turbine and the target speed of the turbine are obtained. If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the synchronous control stage is entered to obtain the estimated synchronization time, which can identify the time required for the dog clutch to drop to zero at the current speed difference change rate. If the estimated synchronization time is less than or equal to the torque response delay time of the engine, a torque reduction request is sent to the engine so that the actual torque of the engine can reach the requested target torque when the speed difference of the dog clutch is near zero, so as to keep the actual transmission torque of the dog clutch less than the designed target torque during the engagement of the dog clutch, so as to avoid the short durability of the dog clutch due to the lack of synchronous friction elements. In addition, since the torque of the engine begins to decrease in advance, it is avoided that the engine transfers too much load to the dog clutch, thereby avoiding the dog clutch from being able to engage smoothly and affecting the performance of the dog clutch. If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened, that is, the control solenoid valve of the dog clutch is opened in advance, so that the dog clutch starts to engage when the speed difference is near zero, so as to avoid the short durability of the dog clutch due to the lack of synchronization friction elements.
[0095] As a possible implementation method, the torque of the clutch to be released can be reduced first, for example, the pressure of the clutch to be released can be reduced, thereby reducing the load of the engine, so that the torque of the engine is greater than the load. If the torque of the engine is greater than the torque of the clutch to be released, the engine speed is increased, and the engine starts to drive the turbine to move, so that the turbine speed starts to increase, so that the actual speed of the turbine approaches the target speed of the turbine, and the clutch to be released starts to enter a slipping state.
[0096] As a possible implementation method, after the clutch to be separated enters the slipping state, the pressure of the clutch to be separated is controlled so that the speed of the turbine increases toward the target speed of the turbine based on the preset acceleration. When the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the aforementioned S402 can be entered.
[0097] As a possible implementation method, after executing S404, that is, after the dog clutch is engaged, the torque request to the engine can be canceled and the clutch to be separated can be opened, such as gradually starting to cancel the torque request to the engine and gradually opening the clutch to be separated to complete the PD control shifting process.
[0098] In order to make the technical solution provided by the embodiments of the present application clearer, Figure 5 The gear control method based on the dog clutch provided in the embodiment of the present application is described with an example.
[0099] See also Figure 5 , this figure is a scenario schematic diagram of a gear control method based on a dog clutch provided in an embodiment of the present application.
[0100] (1) Reduce the torque of the clutch to be released, that is, reduce the load on the engine, so that the target torque of the engine is greater than the load (1→2). It can be understood that "1→2" here means Figure 5 The process changes from stage 1 to stage 2, and the subsequent processes are similar, so I will not go into details.
[0101] (2) If the torque of the engine is greater than the torque of the clutch to be released, the engine speed is increased, and the engine starts to drive the turbine to move, causing the actual speed of the turbine to start to increase, so that the actual speed of the turbine approaches the target speed of the turbine (2→3), and the clutch to be released starts to enter a slipping state.
[0102] (3) After the off-going clutch enters the slipping state, the pressure of the off-going clutch is controlled so that the speed of the turbine increases toward the target speed of the turbine based on the preset acceleration (3→4).
[0103] (4) When the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the Sync control stage (4-7) can be entered.
[0104] (5) If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, that is, after entering the Sync control stage, the torque of the clutch to be released is not increased, so that the acceleration of the turbine remains unchanged (e.g. Figure 5 The target torque of the engine and the torque of the clutch to be released remain relatively unchanged). And according to the actual speed of the turbine and the target speed of the turbine, the estimated synchronization time is calculated.
[0105] (6) If the estimated synchronization time is less than or equal to the engine torque response delay time ( Figure 5 t_Eng), a torque reduction request is sent to the engine ( Figure 5 The engine torque requirement starts to decrease in stage 4, from Figure 5 It can be seen that the requested torque of the engine is lower than the target torque of the engine, and the actual torque of the engine begins to decrease. The requested torque of the engine is the requested torque mentioned above.
[0106] (7) If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch ( Figure 5 t_hyd), then the control solenoid valve of the dog clutch is opened ( Figure 5 In the process, the control solenoid valve of the dog clutch changes from the Off state to the On state in 5 stages).
[0107] (8) After the dog clutch is engaged ( Figure 5 Stage 7), gradually starts to cancel the torque request to the engine ( Figure 5 In the process, the requested torque of the engine starts to gradually increase), and the clutch to be separated is gradually opened to complete the PD control shifting process.
[0108] Therefore, based on the estimated synchronization time, the torque reduction request for the engine and the control solenoid valve for opening the dog clutch in advance can be sent in advance, so that when the speed difference of the dog clutch is near zero, the actual torque of the engine can reach the requested target torque, so as to keep the actual transmission torque of the dog clutch less than the designed target torque during the engagement of the dog clutch, so as to avoid the short durability of the dog clutch due to the lack of synchronous friction elements. And the dog clutch starts to engage only when the speed difference of the dog clutch is near zero, so as to avoid the load of the engine being transferred to the dog clutch, resulting in the dog clutch not being able to engage smoothly and affecting the performance of the dog clutch.
[0109] In addition to the gear position control method based on the dog clutch provided in the embodiment of the present application, a gear position control device based on the dog clutch is also provided. Figure 6 As shown, it includes: an acquisition unit 601 and an execution unit 602;
[0110] The acquisition unit 601 is used to acquire the actual speed of the turbine and the target speed of the turbine;
[0111] The acquisition unit 601 is further configured to acquire an estimated synchronization time if the difference between the actual speed of the turbine and the target speed of the turbine is less than a preset speed difference, wherein the estimated synchronization time is used to identify the time required for the dog clutch to decrease to zero at the current speed difference change rate, and the dog clutch is a clutch to be engaged;
[0112] The execution unit 602 is configured to send a torque reduction request for the engine if the estimated synchronization time is less than or equal to the torque response delay time of the engine;
[0113] The execution unit 602 is further configured to open the control solenoid valve of the dog clutch if the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch.
[0114] It can be seen from the above technical solution that the actual speed of the turbine and the target speed of the turbine are obtained. If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the synchronous control stage is entered to obtain the estimated synchronization time, which can identify the time required for the dog clutch to drop to zero at the current speed difference change rate. If the estimated synchronization time is less than or equal to the torque response delay time of the engine, a torque reduction request is sent to the engine so that the actual torque of the engine can reach the requested target torque when the speed difference of the dog clutch is near zero, so as to keep the actual transmission torque of the dog clutch less than the designed target torque during the engagement of the dog clutch, so as to avoid the short durability of the dog clutch due to the lack of synchronous friction elements. In addition, since the torque of the engine begins to decrease in advance, it is avoided that the engine transfers too much load to the dog clutch, thereby avoiding the dog clutch from being able to engage smoothly and affecting the performance of the dog clutch. If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened, that is, the control solenoid valve of the dog clutch is opened in advance, so that the dog clutch starts to engage when the speed difference is near zero, so as to avoid the short durability of the dog clutch due to the lack of synchronization friction elements.
[0115] As a possible implementation manner, the device further includes a computing unit;
[0116] The acquisition unit 601 is further used to acquire the actual speed of the turbine and the target speed of the turbine;
[0117] The calculation unit is used to calculate the estimated synchronization time according to the actual speed of the turbine and the target speed of the turbine, and the calculation method is as follows:
[0118]
[0119] Wherein, SyncTm_Estd is the estimated synchronization time, TurbSpd is the actual speed of the turbine, and OncSpd is the target speed of the turbine.
[0120] As a possible implementation manner, the execution unit 602 is further configured to:
[0121] If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the acceleration of the turbine is kept unchanged until the estimated synchronization time is less than or equal to the torque response delay time of the engine or the hydraulic control delay time of the dog clutch.
[0122] As a possible implementation manner, the execution unit 602 is specifically configured to:
[0123] The torque of the off-going clutch is not increased in order to keep the acceleration of the turbine constant.
[0124] As a possible implementation manner, the execution unit 602 is further configured to:
[0125] Reducing the torque of the off-going clutch;
[0126] If the torque of the engine is greater than the torque of the off-going clutch, the rotation speed of the engine is increased so that the off-going clutch enters a slipping state.
[0127] As a possible implementation manner, the execution unit 602 is further configured to:
[0128] After the off-going clutch enters the slipping state, the rotation speed of the turbine increases toward the target rotation speed of the turbine based on a preset acceleration by controlling the pressure of the off-going clutch.
[0129] As a possible implementation manner, the execution unit 602 is further configured to:
[0130] After the dog clutch is engaged, the torque request to the engine is removed and the off-going clutch is opened.
[0131] The present application also provides a computer device, see Figure 7, which shows a structural diagram of a computer device provided in an embodiment of the present application, such as Figure 7 As shown, the device includes a memory 710 and a processor 720:
[0132] The memory 710 is used to store program codes and transmit the program codes to the processor;
[0133] The processor 720 is used to execute any one of the gear control methods based on the dog clutch provided in the above embodiments according to the instructions in the program code.
[0134] An embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store a computer program, wherein the computer program is used to execute any one of the dog clutch-based gear control methods provided in the above embodiments.
[0135] The embodiment of the present application also provides a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. The processor of the computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the gear control method based on the dog clutch provided in various optional implementations of the above aspects.
[0136] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the system or device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.
[0137] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.
[0138] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0139] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
[0140] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A gear control method based on a dog clutch, characterized in that: The method comprises: Acquiring an actual rotation speed of a turbine and a target rotation speed of the turbine; If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, an estimated synchronization time is obtained, wherein the estimated synchronization time is used to identify the time required for the dog clutch to drop to zero at the current speed difference change rate, and the dog clutch is a clutch to be engaged; If the estimated synchronization time is less than or equal to the torque response delay time of the engine, sending a torque reduction request for the engine; If the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch, the control solenoid valve of the dog clutch is opened.
2. The method according to claim 1, characterized in that The method further comprises: Acquiring an actual rotation speed of the turbine and a target rotation speed of the turbine; The estimated synchronization time is calculated according to the actual speed of the turbine and the target speed of the turbine, and the calculation method is as follows: Wherein, SyncTm_Estd is the estimated synchronization time, TurbSpd is the actual speed of the turbine, and OncSpd is the target speed of the turbine.
3. The method according to claim 1, characterized in that The method further comprises: If the difference between the actual speed of the turbine and the target speed of the turbine is less than the preset speed difference, the acceleration of the turbine is kept unchanged until the estimated synchronization time is less than or equal to the torque response delay time of the engine or the hydraulic control delay time of the dog clutch.
4. The method according to claim 3, characterized in that The step of maintaining the acceleration of the turbine unchanged comprises: The torque of the off-going clutch is not increased in order to keep the acceleration of the turbine constant.
5. The method according to claim 1, characterized in that The method further comprises: Reducing the torque of the off-going clutch; If the torque of the engine is greater than the torque of the off-going clutch, the rotation speed of the engine is increased so that the off-going clutch enters a slipping state.
6. The method according to claim 5, characterized in that After the to-be-released clutch enters a slipping state, the method further includes: By controlling the pressure of the off-going clutch, the rotation speed of the turbine is increased toward a target rotation speed of the turbine based on a preset acceleration.
7. The method according to claim 1, characterized in that The method further comprises: After the dog clutch has completed engagement, the torque request to the engine is removed and the off-going clutch is opened.
8. A gear control device based on a dog clutch, characterized in that: The device comprises: an acquisition unit and an execution unit; The acquisition unit is used to acquire the actual rotation speed of the turbine and the target rotation speed of the turbine; The acquisition unit is further configured to acquire an estimated synchronization time if a difference between an actual speed of the turbine and a target speed of the turbine is less than a preset speed difference, wherein the estimated synchronization time is used to identify a time required for the dog clutch to decrease to zero at a current speed difference change rate, the dog clutch being a clutch to be engaged; the execution unit is configured to send a torque reduction request for the engine if the estimated synchronization time is less than or equal to a torque response delay time of the engine; The execution unit is further configured to open the control solenoid valve of the dog clutch if the estimated synchronization time is less than or equal to the hydraulic control delay time of the dog clutch.
9. A computer device, characterized in that: The device comprises a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the method according to any one of claims 1 to 7 according to the instructions in the program code.
10. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method according to any one of claims 1 to 7.