Off-gear control method based on dog clutch and related device

Abstract

The invention discloses an out-of-gear control method based on a dog clutch and a related device, if a vehicle gear shifting instruction is obtained in the process that the control state of the dog clutch is a complete combination state, gear shifting is not directly carried out at the moment, and an initial transmission torque and an initial transmission torque preset threshold value are obtained based on the vehicle gear shifting instruction. The current transmission torque is obtained, if the current transmission torque is smaller than or equal to the preset threshold value of the initial transmission torque, it is indicated that the current transmission torque is in a proper size, the separation side oil cylinder pressure of the dog clutch can be increased, the dog clutch can be separated conveniently, and the control state of the dog clutch is changed into the separation state from the combination state; and the out-of-gear operation is completed. Therefore, the initial transmission torque preset threshold value is increased along with the increase of the initial transmission torque, so that the pressure of the separation side oil cylinder of the dog clutch is increased after the current transmission torque is appropriate, and the problem of galloping of an engine or the problem of poor gear shifting performance is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and in particular to a gear-disengagement control method based on a dog clutch and a related device. Background Art

[0002] Compared with other types of transmissions, automatic transmissions with dog clutches have a wider gear ratio range and have the advantages of comfortable driving, low emissions, and good fuel economy. In addition, compared with traditional wet clutches, the design of the dog clutch is smaller in size, simpler in mechanical structure, and has a shorter gear shift response time.

[0003] Both sides of the dog tooth piston are filled with oil. When the dog tooth clutch is ready to engage, the pressure value of the oil cylinder pressure on the engagement side increases, and the pressure value of the oil cylinder pressure on the separation side is zero, and the dog tooth clutch begins to engage under the action of the combined force; conversely, when the dog tooth clutch is ready to separate, the pressure value of the oil cylinder pressure on the engagement side is zero, and the pressure value of the oil cylinder pressure on the separation side increases, and the dog tooth clutch begins to separate under the action of the combined force.

[0004] In the related art, when the driver intends to shift gears, the pressure value of the oil cylinder on the separation side is increased to cause the dog clutch to start disengaging. However, this method may cause the problem of engine runaway or poor shifting performance. Summary of the invention

[0005] In view of the above problems, the present application provides a dog clutch-based disengagement control method and related devices, which are used to avoid the problem of engine runaway or poor shifting performance.

[0006] Based on this, the embodiments of the present application disclose the following technical solutions:

[0007] On the one hand, an embodiment of the present application provides a disengagement control method based on a dog clutch, the method comprising:

[0008] If a vehicle shift command is obtained during the process in which the control state of the dog clutch is in a fully engaged state, an initial transmission torque and an initial transmission torque preset threshold are obtained based on the vehicle shift command, wherein the initial transmission torque is the transmission torque of the dog clutch when the vehicle shift command is obtained, and the initial transmission torque preset threshold is the transmission torque preset threshold corresponding to the initial transmission torque; wherein the higher the initial transmission torque is, the higher the initial transmission torque preset threshold is;

[0009] Get the current transmitted torque;

[0010] If the current transmission torque is less than or equal to the preset threshold value of the initial transmission torque, the separation-side cylinder pressure of the dog clutch is increased.

[0011] Optionally, the method further includes:

[0012] acquiring a hydraulic response time of the dog clutch and a transmission torque change rate of the dog clutch, wherein the transmission torque change rate is determined according to the initial transmission torque;

[0013] The initial transmission torque preset threshold is determined according to the hydraulic response time and the transmission torque change rate.

[0014] Optionally, the method further includes:

[0015] Get the target throttle range corresponding to the current throttle opening;

[0016] Based on the correspondence between the throttle interval and the transfer torque, determining the target transfer torque corresponding to the target throttle opening, wherein in the correspondence between the throttle interval and the transfer torque, the larger the throttle opening included in the throttle interval, the larger the transfer torque corresponding to the throttle interval;

[0017] determining a target pressure value of the disengagement-side oil cylinder pressure of the dog clutch according to the target transmission torque;

[0018] The step of increasing the oil cylinder pressure on the separation side of the dog clutch comprises:

[0019] The disengagement-side cylinder pressure of the dog clutch is increased based on the target pressure value.

[0020] Optionally, determining the separation-side oil cylinder pressure of the dog clutch according to the target transmission torque includes:

[0021] Obtaining the axial friction force generated by the spline of the dog clutch under the target transmission torque;

[0022] The disengagement-side cylinder pressure of the dog clutch is determined according to the target transmission torque and the axial friction force.

[0023] Optionally, in the process of controlling the dog clutch to be disengaged based on the target pressure value, the method further includes:

[0024] Obtaining the current position of the dog-tooth piston;

[0025] If it is determined based on the current position that the position change of the dog-tooth piston within the preset time is greater than or equal to a preset position threshold, then obtaining a residual pressure value;

[0026] Determining an increased pressure value according to the target pressure value and the margin pressure value;

[0027] The dog clutch is controlled to disengage based on the increased pressure value.

[0028] Optionally, in the process of controlling the dog clutch to be disengaged based on the target pressure value, the method further includes:

[0029] Obtaining the current position of the dog-tooth piston;

[0030] If it is determined based on the current position that the position change of the dog gear piston within the preset time is less than a preset position threshold, then obtaining the maximum pressure value of the dog gear clutch;

[0031] The dog clutch is controlled to be disengaged based on the maximum pressure value.

[0032] Optionally, in the process of controlling the dog clutch to be disengaged based on the target pressure value, the method further includes:

[0033] Obtaining the current position of the dog-tooth piston;

[0034] If it is determined based on the current position that the position change of the dog piston within the preset time is less than a preset position threshold, the pressure value of the auxiliary clutch is adjusted to fluctuate up and down.

[0035] On the other hand, the present application provides a dog clutch-based disengagement control device, a first acquisition unit, a second acquisition unit, and an improvement unit;

[0036] The first acquisition unit is used for acquiring an initial transmission torque and an initial transmission torque preset threshold value based on the vehicle shift instruction if the vehicle shift instruction is acquired during the process in which the control state of the dog clutch is in the fully engaged state, wherein the initial transmission torque is the transmission torque of the dog clutch when the vehicle shift instruction is acquired, and the initial transmission torque preset threshold value is the transmission torque preset threshold value corresponding to the initial transmission torque; wherein the higher the initial transmission torque is, the higher the initial transmission torque preset threshold value is;

[0037] The second acquisition unit is used to acquire the current transmission torque;

[0038] The increasing unit is configured to increase the separation-side cylinder pressure of the dog clutch if the current transmission torque is less than or equal to the preset threshold of the initial transmission torque, and to increase the separation-side cylinder pressure of the dog clutch based on the target pressure value.

[0039] Optionally, the dog clutch-based disengagement control device further includes a third acquisition unit and a first determination unit;

[0040] The third acquisition unit is used to acquire the hydraulic response time of the dog clutch and the transmission torque change rate of the dog clutch, wherein the transmission torque change rate is determined according to the initial transmission torque;

[0041] The first determination unit is used to determine the initial transmission torque preset threshold value according to the hydraulic response time and the transmission torque change rate.

[0042] Optionally, the dog clutch-based disengagement control device further includes a fourth acquisition unit, a second determination unit, and a third determination unit;

[0043] The fourth acquisition unit is used to acquire a target throttle range corresponding to a current throttle opening;

[0044] The second determining unit is used to determine the target transfer torque corresponding to the target throttle opening based on the correspondence between the throttle interval and the transfer torque, wherein in the correspondence between the throttle interval and the transfer torque, the larger the throttle opening included in the throttle interval, the larger the transfer torque corresponding to the throttle interval;

[0045] The third determining unit is used to determine a target pressure value of the disengagement-side oil cylinder pressure of the dog clutch according to the target transmission torque;

[0046] The increasing unit is specifically configured to increase the release-side cylinder pressure of the dog clutch based on the target pressure value.

[0047] Optionally, the dog clutch-based disengagement control device further includes a third determination unit, configured to:

[0048] Obtaining the axial friction force generated by the spline of the dog clutch under the target transmission torque;

[0049] The disengagement-side cylinder pressure of the dog clutch is determined according to the target transmission torque and the axial friction force.

[0050] Optionally, the dog clutch-based disengagement control device further includes a fifth acquisition unit, a sixth acquisition unit, a fourth determination unit and a control unit;

[0051] The fifth acquisition unit is used to acquire the current position of the dog gear piston in the process of controlling the dog gear clutch to be disengaged based on the target pressure value;

[0052] The sixth acquisition unit is used to acquire the residual pressure value if the position change of the dog-tooth piston within the preset time is greater than or equal to a preset position threshold value determined based on the current position;

[0053] The fourth determining unit is used to determine the increased pressure value according to the target pressure value and the remaining pressure value;

[0054] The control unit is used to control the dog clutch to disengage based on the increased pressure value.

[0055] Optionally, the dog clutch-based disengagement control device further includes a fifth acquisition unit, a sixth acquisition unit and a control unit;

[0056] The fifth acquisition unit is used to acquire the current position of the dog gear piston in the process of controlling the dog gear clutch to be disengaged based on the target pressure value;

[0057] The sixth acquisition unit is used to acquire the maximum pressure value of the dog clutch if the position change of the dog piston within the preset time is greater than or equal to a preset position threshold value determined based on the current position;

[0058] The control unit is used to control the dog clutch to be disengaged based on the maximum pressure value.

[0059] Optionally, the dog clutch-based disengagement control device further includes a fifth acquisition unit and an adjustment unit;

[0060] The fifth acquisition unit is used to acquire the current position of the dog gear piston in the process of controlling the dog gear clutch to be disengaged based on the target pressure value;

[0061] The adjustment unit is used to adjust the pressure value of the auxiliary clutch to fluctuate up and down if it is determined based on the current position that the position change of the dog piston within the preset time is greater than or equal to a preset position threshold.

[0062] In another aspect, the present application provides a computer device, the device comprising a processor and a memory:

[0063] The memory is used to store program code and transmit the program code to the processor;

[0064] The processor is used to execute the method described in the above aspects according to the instructions in the program code.

[0065] 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.

[0066] 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.

[0067] The advantages of the above technical solution of this application are:

[0068] If the vehicle shift command is obtained during the process that the control state of the dog clutch is in the fully engaged state, the gear shift will not be performed directly at this time, that is, the pressure value of the oil cylinder pressure on the separation side of the dog clutch will not be increased from 0. Instead, the initial transfer torque and the initial transfer torque preset threshold are obtained based on the vehicle shift command. Among them, the initial transfer torque preset threshold is not fixed, but increases with the increase of the initial transfer torque. The current transfer torque is obtained. If the current transfer torque is less than or equal to the initial transfer torque preset threshold, it means that the current transfer torque is at an appropriate size, and the oil cylinder pressure on the separation side of the dog clutch can be increased to start separating the dog clutch, so as to realize that the control state of the dog clutch changes from the engaged state to the separated state, and the gear is disengaged. Therefore, the preset threshold value of the initial transmission torque is no longer fixed, but increases with the increase of the initial transmission torque, so that the separation side cylinder pressure of the dog clutch is increased after the current transmission torque reaches an appropriate size, thereby avoiding the dog clutch using a smaller separation side cylinder pressure setting value when the transmission torque is large, or avoiding the dog clutch using a larger separation side cylinder pressure setting value when the transmission torque is small, that is, avoiding the problem of engine runaway or poor gear shifting performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] 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 creative work.

[0070] Figure 1 is a schematic diagram of a transmission chain of an automatic transmission;

[0071] Figure 2 A schematic diagram of a small torque disengagement process;

[0072] Figure 3 A schematic diagram of a large torque disengagement process;

[0073] Figure 4 A flow chart of a dog clutch-based disengagement control method provided in an embodiment of the present application;

[0074] Figure 5 A schematic diagram of a small torque disengagement process provided in an embodiment of the present application;

[0075] Figure 6 A schematic diagram of a large torque disengagement process provided in an embodiment of the present application;

[0076] Figure 7A schematic diagram of a gear disengagement control device based on a dog clutch provided in an embodiment of the present application;

[0077] Figure 8 A structural diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0078] 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.

[0079] See also Figure 1 , which is a schematic diagram of a transmission chain of an automatic transmission. When the dog clutch is involved in the shifting process, the locking clutch is engaged, and the auxiliary clutch 3 controls the speed difference at both ends of the dog clutch. Figure 1 In the embodiment, both sides of the dog tooth piston of the dog tooth clutch are in a separated state, and the rotation speeds at both ends of the dog tooth clutch can be obtained through the input shaft rotation speed and the output shaft rotation speed, thereby obtaining the speed difference of the dog tooth clutch.

[0080] During the shifting process, the transmission torque at both ends of the dog clutch is adjusted by adjusting the pressure of the auxiliary clutch 3, increasing the pressure value of the separation side cylinder pressure, and reducing the pressure value of the engagement side cylinder pressure. The dog clutch begins to separate under the action of the combined force until the dog clutch is completely separated. However, during the entire disengagement process, the pressure value of the separation side cylinder pressure is basically maintained at a constant value. If the set pressure value is too high, the dog clutch may be disengaged when the dog transmission torque is small, causing the engine to run away; if the set pressure value is too low, the probability of the dog spline getting stuck during the high-torque disengagement process increases, and the dog clutch will continue to slip, affecting the shifting performance. The following is combined with Figure 2 and Figure 3 Explain them separately.

[0081] See also Figure 2 , which is a schematic diagram of a small torque disengagement process. When the driver's intention to shift gears is detected, the dog clutch control state changes from the engaged state to the disengaged state. At this time, the pressure value of the disengagement side cylinder pressure increases, and the pressure value of the engagement side cylinder pressure decreases to 0. The dog clutch begins to disengage under the action of the combined force until the dog clutch is completely disengaged. Figure 2In the case of a small torque transmission, if the pressure value of the cylinder pressure on the separation side is set to a large value, the dog clutch will be quickly disengaged, and the engine speed will increase from 1600rpm to 2500rpm. If the engine speed increases too fast, not only will the output shaft speed fluctuate greatly, but the engine will also run away.

[0082] See also Figure 3 , which is a schematic diagram of a large torque disengagement process. Figure 3 In the example, when the dog clutch is in the engaged state, the pressure value of the cylinder pressure on the separation side is 0, the dog piston is in the engaged state, the engine speed is 2300rpm, and the output shaft speed is 1400rpm. When the dog clutch transmits a large torque, if the pressure value set for the cylinder pressure on the separation side is small, it is not enough to overcome the friction resistance generated by the dog transmission torque, causing the dog clutch to continue to slip, the dog clutch to be separated for a long time, or the dog clutch may be stuck, affecting the shifting performance.

[0083] Based on this, the embodiment of the present application provides a dog clutch-based disengagement control method and related device, which does not directly shift gears after obtaining the vehicle shift command, but shifts gears after the current transmission torque is less than or equal to the initial transmission torque preset threshold. The initial transmission torque preset threshold is no longer fixed, but increases with the increase of the initial transmission torque, so that the separation side oil cylinder pressure of the dog clutch is increased after the current transmission torque reaches an appropriate size, thereby avoiding the dog clutch using a smaller separation side oil cylinder pressure setting pressure value when the transmission torque is large, or avoiding the dog clutch using a larger separation side oil cylinder pressure setting pressure value when the transmission torque is small, that is, avoiding the problem of engine runaway or poor shifting performance.

[0084] Combine the following Figure 4 , a gear disengagement 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 disengagement control method based on a dog clutch provided in an embodiment of the present application, and the method may include S401-S403.

[0085] S401: If a vehicle shift command is obtained while the dog clutch is in a fully engaged state, an initial transmission torque and an initial transmission torque preset threshold are obtained based on the vehicle shift command.

[0086] If the control state of the dog clutch is in a fully engaged state, the pressure value of the oil cylinder pressure on the disengagement side of the dog clutch is 0. If a vehicle shifting instruction is obtained during the process in which the control state of the dog clutch is in a fully engaged state, it means that the driver has the intention to shift gears. In the related technology, the shifting stage is directly entered based on the driver's intention to shift gears, that is, the pressure value of the oil cylinder pressure on the disengagement side of the dog clutch is increased. As can be seen from the above, this method will cause the problem of engine runaway or poor shifting performance.

[0087] Based on this, the embodiment of the present application no longer directly shifts gears based on the vehicle shift command, but obtains the initial transfer torque and the initial transfer torque preset threshold value based on the vehicle shift command. The initial transfer torque is the transfer torque obtained when obtaining the vehicle shift command, and the initial transfer torque preset threshold value is the transfer torque preset threshold value corresponding to the initial transfer torque.

[0088] It should be noted that the higher the initial transmission torque, the higher the preset threshold of the initial transmission torque, that is, the preset threshold of the initial transmission torque is not fixed, but increases with the increase of the initial transmission torque. Therefore, when the initial transmission torque of the dog clutch is small, the corresponding preset threshold of the initial transmission torque is also small, and the dog clutch will not use a larger pressure value set by the separation side oil cylinder pressure when the transmission torque is small. Similarly, when the initial transmission torque of the dog clutch is large, the corresponding preset threshold of the initial transmission torque is also large, and the dog clutch will not use a smaller pressure value set by the separation side oil cylinder pressure when the transmission torque is large.

[0089] As a possible implementation method, the initial transmission torque preset threshold value may be determined based on the hydraulic response time of the dog clutch and the transmission torque change rate of the dog clutch, which may be specifically expressed as the following formula:

[0090] T1=DlyTm×TorqRat

[0091] Wherein, T1 is the preset threshold value of the initial transmission torque, DlyTm is the hydraulic response time, TorqRat is the transmission torque change rate, and the transmission torque change rate refers to the change rate of the transmission torque.

[0092] It should be noted that the hydraulic response time is affected by temperature, and the difference is not big at normal temperature, generally around 50ms. The rate of change of the transmission torque is generally between 0.5Nm / ms and 1.5Nm / ms, so the initial transmission torque preset threshold value T1 is generally between 25Nm and 75Nm. As a possible time mode, the rate of change of the transmission torque is affected by the engine torque, and the greater the initial engine torque, the greater the rate of change of the transmission torque. Among them, the initial engine torque refers to the engine torque obtained when obtaining the vehicle shift command, so the initial engine torque can be collected by the sensor, and the initial transmission torque preset threshold value can be obtained based on the initial engine torque.

[0093] S402: Obtain current transmission torque.

[0094] The current transmission torque is the transmission torque obtained by the dog clutch after obtaining the vehicle shift instruction. Thus, the current transmission torque can be obtained in real time, that is, the transmission torque change of the dog clutch can be monitored in real time.

[0095] S403: If the current transmission torque is less than or equal to the preset threshold of the initial transmission torque, the cylinder pressure on the release side of the dog clutch is increased.

[0096] If the current transmission torque is less than or equal to the preset threshold of the initial transmission torque, it means that the transmission torque of the dog clutch is of an appropriate size and is neither too large nor too small. At this time, the gear shift is performed, that is, the oil cylinder pressure on the separation side of the dog clutch is increased, and / or the oil cylinder pressure on the engagement side of the dog clutch is reduced, so that the dog clutch begins to separate under the action of the combined force until the dog clutch is completely separated, completing the gear disengagement based on the dog clutch. As a possible implementation method, when the dog clutch is completely separated, the oil cylinder pressure on the separation side is controlled to be reduced to a lower level, and the dog clutch is kept in a completely separated position and does not move, so as to ensure that the gear disengagement is completed.

[0097] Since the pressure value of the oil cylinder pressure on the separation side of the dog clutch is 0, the embodiment of the present application does not specifically limit the pressure value of the oil cylinder pressure on the separation side of the dog clutch. As long as there is a pressure value, the oil cylinder pressure on the separation side of the dog clutch can be increased compared to 0. The embodiment of the present application does not specifically limit the pressure value of the oil cylinder pressure on the separation side of the dog clutch, and those skilled in the art can set it according to actual needs. For example, the pressure value is set to a force that can separate the dog clutch.

[0098] As a possible implementation method, considering that the splines at both ends of the dog clutch will generate axial friction under the action of transmitting torque, the hydraulic pressure acting on the dog piston needs to overcome this axial friction to achieve the separation of the dog clutch. Since different throttle openings will generate different axial frictions, graded control can be performed according to the throttle opening, which is specifically explained below based on A1-A4.

[0099] A1: Get the target throttle range corresponding to the current throttle opening.

[0100] Among them, the current throttle opening refers to the throttle opening corresponding to the current transmitted torque. It should be noted that the throttle interval can be divided into multiple. Taking four throttle intervals as an example, a throttle opening less than 5% can be set as a throttle interval (no throttle interval), a throttle opening between 5% and 30% can be set as a throttle interval (small throttle interval), a throttle opening between 30% and 60% can be set as a throttle interval (medium throttle interval), and a throttle opening greater than 60% can be set as a throttle interval (large throttle interval). Alternatively, each throttle opening can be set as a throttle interval, and this application does not make specific limitations on this.

[0101] A2: Based on the corresponding relationship between the throttle range and the transmitted torque, the target transmitted torque corresponding to the target throttle opening is determined.

[0102] Since the transmission torque of the dog clutch is linearly related to the engine torque, and there is also a certain relationship between the engine torque and the throttle opening, a corresponding relationship between the transmission torque of the dog clutch and the throttle range can be established, so that based on the corresponding relationship, the target transmission torque required for the current throttle opening can be quickly determined.

[0103] Among them, in the correspondence between the throttle range and the transmission torque, the larger the throttle opening included in the throttle range, the larger the transmission torque corresponding to the throttle range, or in other words, the higher the level of throttle opening, the larger the corresponding transmission torque. For example, the transmission torque corresponding to the no throttle range is 30Nm, the transmission torque corresponding to the small throttle range is 50Nm, the transmission torque corresponding to the medium throttle range is 80Nm, and the transmission torque corresponding to the large throttle range is 100Nm.

[0104] A3: Determine the cylinder pressure on the disengagement side of the dog clutch based on the target transmission torque.

[0105] Therefore, the oil cylinder pressure on the disengagement side of the dog clutch can be estimated based on the target transfer torque. For example, some transfer torque margin can be directly added to the target transfer torque, and the axial friction force that may be generated can be dealt with based on the transfer torque margin. Finally, the oil cylinder pressure on the disengagement side of the dog clutch can be determined based on the target transfer torque and the transfer torque margin.

[0106] As a possible implementation method, since the axial friction generated by different throttle openings is different, for example, the axial friction generated by the throttle opening in the large throttle range is greater than the axial friction generated by the throttle opening in the small throttle range, the axial friction corresponding to different throttle openings can be quantified based on the target transmission torque, that is, the axial friction generated by the spline of the dog clutch under the target transmission torque is obtained, and the cylinder pressure on the separation side of the dog clutch is determined according to the target transmission torque and the axial friction, which can be expressed as the following formula:

[0107]

[0108] Among them, P is the cylinder pressure on the disengagement side of the dog clutch, F is the axial friction force calculated by the target transmission torque, A is the cylinder area of ​​the dog clutch, μ is the friction coefficient, T is the target transmission torque, R is the contact pitch circle area of ​​the dog clutch, and α is the tooth profile angle.

[0109] A4: Increase the disengagement cylinder pressure of the dog clutch based on the target pressure value.

[0110] It can be seen from the above technical solution that when the control state of the dog clutch is in the fully engaged state, the vehicle shift command is obtained, and the gear shift is no longer performed directly, that is, the pressure value of the oil cylinder pressure on the separation side of the dog clutch is no longer increased from 0. Instead, the initial transfer torque and the initial transfer torque preset threshold are obtained based on the vehicle shift command. Among them, the initial transfer torque preset threshold is not fixed, but increases with the increase of the initial transfer torque. The current transfer torque is obtained. If the current transfer torque is less than or equal to the initial transfer torque preset threshold, it means that the current transfer torque is at an appropriate size, and the oil cylinder pressure on the separation side of the dog clutch can be increased to start separating the dog clutch, so as to realize that the control state of the dog clutch changes from the engaged state to the separated state, and the gear is disengaged.

[0111] Therefore, the preset threshold value of the initial transmission torque is no longer fixed, but increases with the increase of the initial transmission torque, so that the separation side cylinder pressure of the dog clutch is increased after the current transmission torque reaches an appropriate size, thereby avoiding the dog clutch using a smaller separation side cylinder pressure setting value when the transmission torque is large, or avoiding the dog clutch using a larger separation side cylinder pressure setting value when the transmission torque is small, that is, avoiding the problem of engine runaway or poor gear shifting performance.

[0112] As a possible implementation method, in the process of controlling the dog clutch to disengage based on the target pressure value, the gear may be disengaged slowly and the gear may be stuck. Based on this, the embodiment of the present application also provides a corresponding solution. The following are explained separately.

[0113] Method 1: Dealing with the situation of slow gear shifting.

[0114] The current position of the dog tooth piston is obtained. If the position change of the dog tooth piston within the preset time is greater than or equal to the preset position threshold value based on the current position, or in other words, the dog tooth position change is small within the preset time, it means that the current target pressure value for the dog tooth clutch separation is small, so the residual pressure value can be obtained, such as the residual pressure value can be 0.3 times the target pressure value, and then the increased pressure value is determined according to the target pressure value and the residual pressure value, such as the increased pressure value can be 1.3 times the target pressure value. Finally, the dog tooth clutch separation of the dog tooth clutch is controlled based on the increased pressure value.

[0115] Therefore, within the preset time, when the dog tooth position changes slightly, the target pressure value for separating the dog tooth clutch can be increased based on the residual pressure value to obtain an increased pressure value, and the dog tooth clutch can be controlled to separate quickly based on the larger increased pressure value.

[0116] Method 2: Dealing with stuck teeth.

[0117] The current position of the dog tooth piston is obtained. If the position change of the dog tooth piston within the preset time is less than the preset position threshold value based on the current position, or the dog tooth position has basically not changed within the preset time, it means that the current dog tooth clutch has a stuck problem, or the current target pressure value for the dog tooth clutch separation is too small, resulting in stuck teeth. Therefore, the maximum pressure value of the dog tooth clutch can be obtained, and the dog tooth clutch separation of the dog tooth clutch can be controlled based on the maximum pressure value. As a possible implementation method, after the stuck tooth problem is eliminated, the pressure controlling the dog tooth clutch separation of the dog tooth clutch can be restored to the target pressure value.

[0118] Therefore, if the dog tooth position does not change substantially within the preset time, it indicates that the dog tooth clutch currently has a stuck tooth problem. The maximum pressure value of the dog tooth clutch can be obtained, and the dog tooth clutch separation can be controlled based on the maximum pressure value. That is, the pressure value can be increased as much as possible when the dog tooth clutch hardware permits, so as to quickly eliminate the stuck tooth problem.

[0119] As a possible implementation method, after a tooth sticking problem occurs, the pressure value of the auxiliary clutch can be adjusted to fluctuate up and down. For example, the pressure value of the auxiliary clutch can be adjusted to fluctuate slightly up and down so that the transmission torque of the dog clutch fluctuates accordingly, thereby eliminating the tooth sticking problem.

[0120] In order to make the technical solution provided by the embodiments of the present application clearer, Figure 5 and Figure 6 The gear disengagement control method based on the dog clutch provided in the embodiment of the present application is described.

[0121] S1: The control state of the dog clutch is the fully engaged state, at which time the pressure value of the oil cylinder pressure on the separation side of the dog clutch is 0.

[0122] S2: If a vehicle shift command is obtained while the dog clutch is in a fully engaged state, an initial transmission torque and an initial transmission torque preset threshold are obtained based on the vehicle shift command.

[0123] S3: In the gear-shifting preparation stage, the current transmission torque is obtained in real time. If the current transmission torque is less than or equal to the preset threshold of the initial transmission torque, the normal gear-shifting stage is entered.

[0124] S4: In the normal disengagement stage, the target throttle range corresponding to the current throttle opening is obtained, and the target transmission torque corresponding to the target throttle opening is determined based on the corresponding relationship between the throttle range and the transmission torque. The target pressure value of the cylinder pressure on the disengagement side of the dog clutch is determined according to the target transmission torque. The axial friction force generated by the spline of the dog clutch under the target transmission torque is obtained, and the cylinder pressure on the disengagement side of the dog clutch is determined according to the target transmission torque and the axial friction force. The cylinder pressure on the disengagement side of the dog clutch is increased based on the target pressure value.

[0125] S5: In the normal disengagement stage, the current position of the dog tooth piston is obtained. If the position change of the dog tooth piston within the preset time is greater than or equal to the preset position threshold value based on the current position, the residual pressure value is obtained, and the increased pressure value is determined according to the target pressure value and the residual pressure value. The dog tooth clutch is controlled to separate based on the increased pressure value.

[0126] S6: In the normal disengagement stage, the current position of the dog tooth piston is obtained. If the position change of the dog tooth piston within the preset time is less than the preset position threshold determined based on the current position, the maximum pressure value of the dog tooth clutch is obtained, and the dog tooth clutch separation is controlled based on the maximum pressure value, or the pressure value of the auxiliary clutch is adjusted to fluctuate up and down.

[0127] S7: When the dog clutch is completely disengaged, the oil cylinder pressure on the disengagement side is controlled to drop to a lower level, keeping the dog clutch in the completely disengaged position and the gear shifting is completed.

[0128] See also Figure 5 , which is a schematic diagram of a small torque disengagement process provided in an embodiment of the present application.

[0129] When it is detected that the driver intends to shift gears, the pressure value of the separation side cylinder pressure is no longer directly increased, but the gear disengagement preparation stage is entered, that is, the control state of the dog clutch is changed from the engaged state to the ready-to-disengage state. At this time, the pressure value of the separation side cylinder pressure is still 0.

[0130] In the disengagement preparation stage, the current transmission torque of the dog clutch is detected in real time. If the current transmission torque is lower than the preset threshold of the initial transmission torque, the normal disengagement stage is entered, that is, the control state of the dog clutch changes from the preparation disengagement state to the normal disengagement state, and the pressure value of the disengagement side oil cylinder pressure is increased.

[0131] In the normal disengagement stage, if the position change of the dog gear piston is very small within the preset time, that is, the change of the dog gear position is small, it means that the current target pressure value for the dog gear clutch separation is small, and the pressure value of the separation side oil cylinder pressure needs to be further increased to make the dog gear clutch separate quickly. After the piston is completely separated, the separation side oil cylinder pressure can be controlled to be reduced to a lower level to keep the dog gear clutch in the completely separated position and immobile to ensure the completion of the disengagement.

[0132] It should be noted that, although the pressure value of the separation side oil cylinder is further increased, the output shaft speed will produce a certain vibration. It should be noted that the amplitude of the vibration is less than Figure 2 The amplitude produced in .

[0133] See also Figure 6 , which is a schematic diagram of a large torque disengagement process provided in an embodiment of the present application.

[0134] When it is detected that the driver intends to shift gears, the pressure value of the separation side cylinder pressure is no longer directly increased, but the gear disengagement preparation stage is entered, that is, the control state of the dog clutch is changed from the engaged state to the ready-to-disengage state. At this time, the pressure value of the separation side cylinder pressure is still 0.

[0135] In the disengagement preparation stage, the current transmission torque of the dog clutch is detected in real time. If the current transmission torque is lower than the preset threshold of the initial transmission torque, the normal disengagement stage is entered, that is, the control state of the dog clutch changes from the preparation disengagement state to the normal disengagement state, and the pressure value of the disengagement side oil cylinder pressure is increased.

[0136] In the normal disengagement stage, the target throttle range corresponding to the current throttle opening is obtained, and the target transmission torque corresponding to the target throttle opening is determined based on the corresponding relationship between the throttle range and the transmission torque. The target pressure value of the cylinder pressure on the disengagement side of the dog clutch is determined according to the target transmission torque. The axial friction force generated by the spline of the dog clutch under the target transmission torque is obtained, and the cylinder pressure on the disengagement side of the dog clutch is determined according to the target transmission torque and the axial friction force. The cylinder pressure on the disengagement side of the dog clutch is increased based on the target pressure value. In other words, graded control is performed according to the throttle opening.

[0137] In the normal disengagement stage, if the position change of the dog gear piston is very small within the preset time, that is, the change of the dog gear position is small, it means that the current target pressure value for the dog gear clutch separation is small, and the pressure value of the separation side oil cylinder pressure needs to be further increased to make the dog gear clutch separate quickly. Therefore, by optimizing the pressure value of the separation side oil cylinder pressure, the occurrence of stuck gear is reduced.

[0138] In addition to the dog clutch-based disengagement control method provided in the embodiment of the present application, a dog clutch-based disengagement control device is also provided, such as Figure 7 As shown, the dog clutch-based gear-disengagement control device includes: a first acquisition unit 701, a second acquisition unit 702 and an improvement unit 703;

[0139] The first acquisition unit 701 is used for acquiring an initial transmission torque and an initial transmission torque preset threshold value based on the vehicle shift instruction if the vehicle shift instruction is acquired during the process in which the control state of the dog clutch is in the fully engaged state, wherein the initial transmission torque is the transmission torque of the dog clutch when the vehicle shift instruction is acquired, and the initial transmission torque preset threshold value is the transmission torque preset threshold value corresponding to the initial transmission torque; wherein the higher the initial transmission torque is, the higher the initial transmission torque preset threshold value is;

[0140] The second acquisition unit 702 is used to acquire the current transmission torque;

[0141] The increasing unit 703 is configured to increase the oil cylinder pressure on the separation side of the dog clutch if the current transmission torque is less than or equal to the preset threshold of the initial transmission torque, and to increase the oil cylinder pressure on the separation side of the dog clutch based on the target pressure value.

[0142] It can be seen from the above technical solution that if the vehicle shift command is obtained during the process that the control state of the dog clutch is in the fully engaged state, the gear shift will no longer be performed directly, that is, the pressure value of the oil cylinder pressure on the separation side of the dog clutch will no longer be increased from 0. Instead, the initial transfer torque and the initial transfer torque preset threshold are obtained based on the vehicle shift command. Among them, the initial transfer torque preset threshold is not fixed, but increases with the increase of the initial transfer torque. The current transfer torque is obtained. If the current transfer torque is less than or equal to the initial transfer torque preset threshold, it means that the current transfer torque is at an appropriate size, and the oil cylinder pressure on the separation side of the dog clutch can be increased to start separating the dog clutch, so as to realize that the control state of the dog clutch changes from the engaged state to the separated state, and the gear is disengaged.

[0143] Therefore, the preset threshold value of the initial transmission torque is no longer fixed, but increases with the increase of the initial transmission torque, so that the separation side cylinder pressure of the dog clutch is increased after the current transmission torque reaches an appropriate size, thereby avoiding the dog clutch using a smaller separation side cylinder pressure setting value when the transmission torque is large, or avoiding the dog clutch using a larger separation side cylinder pressure setting value when the transmission torque is small, that is, avoiding the problem of engine runaway or poor gear shifting performance.

[0144] As a possible implementation, the dog clutch-based gear-disengagement control device further includes a third acquisition unit and a first determination unit;

[0145] The third acquisition unit is used to acquire the hydraulic response time of the dog clutch and the transmission torque change rate of the dog clutch, wherein the transmission torque change rate is determined according to the initial transmission torque;

[0146] The first determination unit is used to determine the initial transmission torque preset threshold value according to the hydraulic response time and the transmission torque change rate.

[0147] As a possible implementation, the dog clutch-based gear disengagement control device further includes a fourth acquisition unit, a second determination unit, and a third determination unit;

[0148] The fourth acquisition unit is used to acquire a target throttle range corresponding to a current throttle opening;

[0149] The second determining unit is used to determine the target transfer torque corresponding to the target throttle opening based on the correspondence between the throttle interval and the transfer torque, wherein in the correspondence between the throttle interval and the transfer torque, the larger the throttle opening included in the throttle interval, the larger the transfer torque corresponding to the throttle interval;

[0150] The third determining unit is used to determine a target pressure value of the disengagement-side oil cylinder pressure of the dog clutch according to the target transmission torque;

[0151] The increasing unit 703 is specifically configured to increase the oil cylinder pressure on the release side of the dog clutch based on the target pressure value.

[0152] As a possible implementation, the dog clutch-based disengagement control device further includes a third determination unit, which is used to:

[0153] Obtaining the axial friction force generated by the spline of the dog clutch under the target transmission torque;

[0154] The disengagement-side cylinder pressure of the dog clutch is determined according to the target transmission torque and the axial friction force.

[0155] As a possible implementation, the dog clutch-based disengagement control device further includes a fifth acquisition unit, a sixth acquisition unit, a fourth determination unit and a control unit;

[0156] The fifth acquisition unit is used to acquire the current position of the dog gear piston in the process of controlling the dog gear clutch to be disengaged based on the target pressure value;

[0157] The sixth acquisition unit is used to acquire the residual pressure value if the position change of the dog-tooth piston within the preset time is greater than or equal to a preset position threshold value determined based on the current position;

[0158] The fourth determining unit is used to determine the increased pressure value according to the target pressure value and the remaining pressure value;

[0159] The control unit is used to control the dog clutch to disengage based on the increased pressure value.

[0160] As a possible implementation, the dog clutch-based gear-disengagement control device further includes a fifth acquisition unit, a sixth acquisition unit and a control unit;

[0161] The fifth acquisition unit is used to acquire the current position of the dog gear piston in the process of controlling the dog gear clutch to be disengaged based on the target pressure value;

[0162] The sixth acquisition unit is used to acquire the maximum pressure value of the dog clutch if the position change of the dog piston within the preset time is greater than or equal to a preset position threshold value determined based on the current position;

[0163] The control unit is used to control the dog clutch to be disengaged based on the maximum pressure value.

[0164] As a possible implementation, the dog clutch-based gear-disengagement control device further includes a fifth acquisition unit and an adjustment unit;

[0165] The fifth acquisition unit is used to acquire the current position of the dog gear piston in the process of controlling the dog gear clutch to be disengaged based on the target pressure value;

[0166] The adjustment unit is used to adjust the pressure value of the auxiliary clutch to fluctuate up and down if it is determined based on the current position that the position change of the dog piston within the preset time is greater than or equal to a preset position threshold.

[0167] The present application also provides a computer device, see Figure 8 , which shows a structural diagram of a computer device provided in an embodiment of the present application, such as Figure 8 As shown, the device includes a memory 810 and a processor 820:

[0168] The memory 810 is used to store program codes and transmit the program codes to the processor;

[0169] The processor 820 is used to execute any one of the dog clutch-based gear disengagement control methods provided in the above embodiments according to the instructions in the program code.

[0170] 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 disengagement control methods provided in the above embodiments.

[0171] 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 dog clutch-based gear disengagement control method provided in various optional implementations of the above aspects.

[0172] 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.

[0173] 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.

[0174] 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.

[0175] 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.

[0176] 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 disengagement control method based on a dog clutch, characterized in that: The method comprises: If a vehicle shift command is obtained during the process in which the control state of the dog clutch is in a fully engaged state, an initial transmission torque and an initial transmission torque preset threshold are obtained based on the vehicle shift command, wherein the initial transmission torque is the transmission torque of the dog clutch when the vehicle shift command is obtained, and the initial transmission torque preset threshold is the transmission torque preset threshold corresponding to the initial transmission torque; wherein the higher the initial transmission torque is, the higher the initial transmission torque preset threshold is; Get the current transmitted torque; If the current transmission torque is less than or equal to the preset threshold value of the initial transmission torque, the separation-side cylinder pressure of the dog clutch is increased.

2. The method according to claim 1, characterized in that The method further comprises: acquiring a hydraulic response time of the dog clutch and a transmission torque change rate of the dog clutch, wherein the transmission torque change rate is determined according to the initial transmission torque; The initial transmission torque preset threshold is determined according to the hydraulic response time and the transmission torque change rate.

3. The method according to claim 1, characterized in that The method further comprises: Get the target throttle range corresponding to the current throttle opening; Based on the correspondence between the throttle interval and the transfer torque, determining the target transfer torque corresponding to the target throttle opening, wherein in the correspondence between the throttle interval and the transfer torque, the larger the throttle opening included in the throttle interval, the larger the transfer torque corresponding to the throttle interval; determining a target pressure value of the disengagement-side oil cylinder pressure of the dog clutch according to the target transmission torque; The step of increasing the oil cylinder pressure on the separation side of the dog clutch comprises: The disengagement-side cylinder pressure of the dog clutch is increased based on the target pressure value.

4. The method according to claim 3, characterized in that The step of determining the release-side oil cylinder pressure of the dog clutch according to the target transmission torque comprises: Obtaining the axial friction force generated by the spline of the dog clutch under the target transmission torque; The disengagement-side cylinder pressure of the dog clutch is determined according to the target transmission torque and the axial friction force.

5. The method according to claim 3, characterized in that: In the process of controlling the dog clutch to be disengaged based on the target pressure value, the method further includes: Obtaining the current position of the dog-tooth piston; If it is determined based on the current position that the position change of the dog-tooth piston within the preset time is greater than or equal to a preset position threshold, then obtaining a residual pressure value; Determining an increased pressure value according to the target pressure value and the margin pressure value; The dog clutch is controlled to disengage based on the increased pressure value.

6. The method according to claim 3, characterized in that: In the process of controlling the dog clutch to be disengaged based on the target pressure value, the method further includes: Obtaining the current position of the dog-tooth piston; If it is determined based on the current position that the position change of the dog gear piston within the preset time is less than a preset position threshold, then obtaining the maximum pressure value of the dog gear clutch; The dog clutch is controlled to be disengaged based on the maximum pressure value.

7. The method according to claim 3, characterized in that In the process of controlling the dog clutch to be disengaged based on the target pressure value, the method further includes: Obtaining the current position of the dog-tooth piston; If it is determined based on the current position that the position change of the dog piston within the preset time is less than a preset position threshold, the pressure value of the auxiliary clutch is adjusted to fluctuate up and down.

8. A gear disengagement control device based on a dog clutch, characterized in that: The device comprises: a first acquisition unit, a second acquisition unit and an improvement unit; The first acquisition unit is used for acquiring an initial transmission torque and an initial transmission torque preset threshold value based on the vehicle shift instruction if the vehicle shift instruction is acquired during the process in which the control state of the dog clutch is in the fully engaged state, wherein the initial transmission torque is the transmission torque of the dog clutch when the vehicle shift instruction is acquired, and the initial transmission torque preset threshold value is the transmission torque preset threshold value corresponding to the initial transmission torque; wherein the higher the initial transmission torque is, the higher the initial transmission torque preset threshold value is; The second acquisition unit is used to acquire the current transmission torque; The increasing unit is configured to increase the separation-side cylinder pressure of the dog clutch if the current transmission torque is less than or equal to the preset threshold of the initial transmission torque, and to increase the separation-side cylinder pressure of the dog clutch based on the target pressure value.

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.

Images