A method and device for controlling acceleration by pressing the accelerator during vehicle downshifting

Abstract

The present application provides a method and device for controlling acceleration by pressing the accelerator during a vehicle downshift. During the accelerator acceleration process during the downshift, the offgoing clutch is controlled to increase from a first initial torque to a first target torque, and the torque of the oncoming clutch is controlled to decrease from a second initial torque to a second target torque. When it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque command is sent to the offgoing clutch so that the offgoing clutch controls its own torque to increase in the form of a parabola to the torque indicated by the parabolic command based on the parabolic torque command. When it is detected that the current torque of the offgoing clutch is the torque indicated by the parabolic command, the torque of the offgoing clutch is controlled to increase linearly to a third target torque. The present application can ensure power response and avoid jerking and noise during the accelerator acceleration process during vehicle downshift.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and more particularly to a method and device for controlling acceleration when pressing the accelerator during a vehicle downshift process. Background Art

[0002] Vehicles frequently experience various gear shifting conditions while driving. During the gear shifting process, if the driver's intention changes, it is easy to cause shock or clank noise. For example, when the vehicle is coasting and downshifting, the driver's own demand is to slow down, but if the driver steps on the accelerator during the downshifting process, the driver's demand becomes acceleration, which will cause shock or clank noise.

[0003] In the prior art, a torque limiting strategy can be used to solve the problem of the "clunk" noise generated when the driver steps on the accelerator during downshifting. However, this approach still has the problem of jerking. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present application provides a method and device for controlling acceleration when pressing the accelerator during vehicle downshifting, so as to avoid jerking and noise during acceleration when pressing the accelerator during vehicle downshifting.

[0005] In order to achieve the above objectives, this application provides the following technical solutions:

[0006] A first aspect of the present invention discloses a method for controlling acceleration during vehicle downshifting by pressing the accelerator pedal, which is applied to a transmission. The method comprises:

[0007] During a vehicle downshift, when it is detected that the driver has stepped on the accelerator, the offgoing clutch is controlled to increase its torque from a first initial torque to a first target torque, and the oncoming clutch is controlled to decrease its torque from a second initial torque to a second target torque; wherein the offgoing clutch is a clutch currently in an engaged state; the first initial torque is the torque of the offgoing clutch corresponding to the gear position of the vehicle before the downshift; the first target torque is less than the torque corresponding to the corresponding Lash point of the vehicle; the oncoming clutch is a clutch currently in a non-engaged state; and the second initial torque is the torque of the oncoming clutch corresponding to the gear position of the vehicle before the downshift;

[0008] When it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque command is sent to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in a parabolic form to the torque indicated by the parabolic command based on the parabolic torque command; wherein the torque indicated by the parabolic command is greater than the torque corresponding to the corresponding Lash point of the vehicle;

[0009] When it is detected that the current torque of the offgoing clutch is the torque indicated by the parabola instruction, the torque of the offgoing clutch is controlled to increase linearly until the torque of the offgoing clutch increases linearly to a third target torque.

[0010] Optionally, before the vehicle downshifts, the method further includes:

[0011] During vehicle coasting, when a downshift request is received, the torque of the offgoing clutch is controlled to be maintained at the first initial torque, so as to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

[0012] Optionally, during the process of downshifting the vehicle, when it is detected that the driver has stepped on the accelerator, the method further includes:

[0013] A first torque control request is sent to an engine of the vehicle, so that the engine controls its own torque to maintain at a third initial torque based on the torque control request; wherein the third initial torque is the torque of the engine when the first torque control request is received.

[0014] Optionally, when it is detected that the current torque of the offgoing clutch is the first target torque, the method further includes:

[0015] A second torque control request is sent to the engine, so that the engine controls its own torque to drop from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then controls the torque of the engine to slowly increase until it is detected that the engine speed is synchronized with the speed of the oncoming clutch.

[0016] Optionally, the method further includes:

[0017] When it is detected that the engine speed is synchronized with the speed of the oncoming clutch, the oncoming clutch is controlled to quickly increase from the third target torque to a fourth target torque, and the torque of the offgoing clutch is controlled to quickly decrease from the second target torque to a fifth target torque.

[0018] A second aspect of the present application discloses a device for controlling acceleration during vehicle downshifting by pressing the accelerator pedal, which is applied to a transmission. The device comprises:

[0019] a first control unit configured to control, during a vehicle downshift, when it is detected that the driver has stepped on the accelerator, to control the torque of the offgoing clutch to increase from a first initial torque to a first target torque, and to control the torque of the oncoming clutch to decrease from a second initial torque to a second target torque; wherein the offgoing clutch is a clutch currently in an engaged state; the first initial torque is the torque of the offgoing clutch corresponding to the gear position of the vehicle before the downshift; the first target torque is less than the torque corresponding to the corresponding Lash point of the vehicle; the oncoming clutch is a clutch currently in a non-engaged state; and the second initial torque is the torque of the oncoming clutch corresponding to the gear position of the vehicle before the downshift;

[0020] a first transmission unit, configured to, when detecting that the current torque of the offgoing clutch is the first target torque, transmit a parabolic torque command to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in a parabolic manner to the torque indicated by the parabolic command based on the parabolic torque command; wherein the torque indicated by the parabolic command is greater than the torque corresponding to the corresponding Lash point of the vehicle;

[0021] The second control unit is configured to control the torque of the offgoing clutch to increase linearly when it is detected that the current torque of the offgoing clutch is the torque indicated by the parabola instruction, until the torque of the offgoing clutch increases linearly to a third target torque.

[0022] Optionally, the device further includes:

[0023] The third control unit is configured to control the torque of the offgoing clutch to maintain at the first initial torque when a downshift request is received during vehicle coasting, so as to control the vehicle to slowly downshift from a current gear to a target gear indicated by the downshift request.

[0024] Optionally, the device further includes:

[0025] The second sending unit is used to send a first torque control request to the engine of the vehicle, so that the engine controls its own torque to maintain at a third initial torque based on the torque control request; wherein the third initial torque is the torque of the engine when receiving the first torque control request.

[0026] Optionally, the device further includes:

[0027] a third sending unit, configured to send a second torque control request to the engine, so that the engine controls its own torque to drop from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then controls the torque of the engine to slowly increase until it is detected that the engine speed is synchronized with the speed of the oncoming clutch.

[0028] Optionally, the device further includes:

[0029] The fourth control unit is used to control the oncoming clutch to quickly increase from the third target torque to the fourth target torque, and to control the torque of the offgoing clutch to quickly decrease from the second target torque to the fifth target torque when it is detected that the speed of the engine is synchronized with the speed of the oncoming clutch.

[0030] The present application provides a method and device for controlling acceleration by pressing the accelerator during vehicle downshifting, which is applied to a transmission. During the vehicle downshifting process, when it is detected that the driver has pressed the accelerator, the offgoing clutch is controlled to increase from a first initial torque to a first target torque, and the torque of the oncoming clutch is controlled to decrease from a second initial torque to a second target torque; when it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque instruction is sent to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction; when it is detected that the current torque of the offgoing clutch is When the torque indicated by the parabola instruction is reached, the torque of the Offgoing clutch is controlled to rise linearly until the torque of the Offgoing clutch rises linearly to the second target torque, wherein the Offgoing clutch is the clutch that is currently in the engaged state; the Oncoming clutch is the clutch that is currently in the non-engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear position of the vehicle before downshifting; the second initial torque is the torque of the Oncoming clutch corresponding to the gear position of the vehicle before downshifting; the first target torque is less than the torque corresponding to the corresponding Lash point of the vehicle; the torque indicated by the parabola instruction is greater than the torque corresponding to the corresponding Lash point of the vehicle. The technical solution provided by the present invention is that during the process of vehicle downshifting and acceleration, the Offgoing clutch currently in the engaged state is controlled to quickly increase from the current torque (first initial torque). When it rises to near the torque corresponding to the Lash point corresponding to the vehicle (first target torque), the torque of the Offgoing clutch is controlled to increase in the form of a parabola based on the parabolic instruction to the torque indicated by the parabolic instruction, thereby smoothly passing the Lash point corresponding to the vehicle and avoiding the problem of vehicle jerking when accelerating during the downshifting process; and when it is detected that the current torque of the Offgoing clutch is the torque indicated by the parabolic instruction, the torque of the Offgoing clutch is controlled to increase linearly, which can avoid noise during the vehicle's downshifting and acceleration process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0032] Figure 1A schematic diagram of the fluctuations of the torque of each clutch, and the speed and torque of the engine during downshift acceleration using a torque limiting strategy provided in the prior art;

[0033] Figure 2 A schematic diagram of the meshing conditions of each gear and the odd-even clutch after the vehicle shifts from 3rd gear to 2nd gear, provided in the prior art;

[0034] Figure 3 A schematic diagram of the engagement of various gears and odd / even clutches when a vehicle enters a speed control stage of shifting from 3rd gear to 2nd gear and detects that the driver has stepped on the accelerator is provided in the prior art;

[0035] Figure 4 A schematic diagram of the meshing conditions of each gear and the odd-even clutch after a vehicle shifts from 3rd gear active to 2nd gear active, provided by the prior art;

[0036] Figure 5 A flowchart of a method for controlling accelerator pedal acceleration during vehicle downshifting provided by an embodiment of the present invention;

[0037] Figure 6 A schematic structural diagram of a gearbox provided by an embodiment of the present invention;

[0038] Figure 7 An exemplary diagram of fluctuations in the torque of each clutch, the speed of each clutch, the torque of the engine, and the speed of the engine during a downshift acceleration process, after applying the vehicle downshift acceleration control method provided by the present application, is provided in an embodiment of the present invention;

[0039] Figure 8 A flow chart of another method for controlling acceleration by pressing the accelerator during vehicle downshifting provided by an embodiment of the present invention;

[0040] Figure 9 A schematic structural diagram of a throttle acceleration control device during vehicle downshifting provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0042] As used herein, the term "including" and its variations are open-ended, i.e., "including but not limited to." The term "based on" means "based, at least in part, on." The term "one embodiment" means "at least one embodiment," the term "another embodiment" means "at least one additional embodiment," and the term "some embodiments" means "at least some embodiments." Other terms are defined in the following description.

[0043] It should be noted that the concepts of "first" and "second" mentioned in the disclosure of the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0044] It should be noted that the modifications of "one" and "multiple" mentioned in the disclosure of the present invention are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise clearly indicated in the context, they should be understood as "one or more".

[0045] From the above background technology, it can be known that in the prior art, a torque limiting strategy can be used to solve the problem of jerking or clamping noise when the driver steps on the accelerator during downshifting. The specific process of the torque limiting strategy can be: by controlling the oncoming clutch to release pressure below the corresponding Lash point of the vehicle, such as Figure 1 Phase A in the engine; at the same time, request the Engine Management System (EMS) to limit torque. When the engine speed is detected to exceed the speed of the oncoming clutch, the engine torque is guided to recover and the torque ramp of the oncoming clutch is controlled to increase. Figure 1 However, this control method usually has two problems. The offgoing clutch is the clutch that is currently in the engaged state, and the oncoming clutch is the clutch that is currently in the non-engaged state. Figure 1 This is an example diagram of the fluctuations of the torque of each clutch, the speed of each clutch, the torque of the engine, and the speed of the engine after applying the torque limiting strategy during downshift acceleration.

[0046] Among them, OncomingSpeed ​​is the speed of the oncoming clutch, OffgoingSpeed ​​is the speed of the offgoing clutch, EngineSpeed ​​is the speed of the engine, OncomingTorq is the torque of the oncoming clutch, OffgoingTorq is the torque of the offgoing clutch, and EngineTorqueLimitRequest is the torque of the engine.

[0047] Problem 1: The EMS torque is limited, and the torque of the oncoming clutch is below the corresponding Lash point of the vehicle, which will result in no power output after the accelerator is pressed, resulting in slow power response of the vehicle; Problem 2: When in stage B, the oncoming clutch rises linearly at a certain slope, that is, when the ramp rises, the actual required torque of the engine is actually very large. Because the driver in front has stepped on the accelerator, the torque of the oncoming clutch needs to rise linearly at a certain slope faster in stage B to respond to the torque demand as soon as possible. However, this involves the problem of transmission system reversing and passing the Lash point, which is prone to jerking and clamp noise.

[0048] In order to better understand the above-mentioned problems involving transmission system reversing and passing the Lash point, which may lead to jerking and clamp noise, the following example analysis is given.

[0049] For example, the vehicle is currently in the process of downshifting from 3rd gear to 2nd gear, and the driver steps on the accelerator. The transmission process between the transmission system and the gears during the whole process can be divided into the following four stages.

[0050] The first stage: reverse dragging in 3rd gear. Before entering 3rd gear and dropping down to 2nd gear, it has been coasting in 3rd gear, so this stage has been reverse dragging in 3rd gear.

[0051] The second stage: reverse drag in 2nd gear. After entering the control of shifting from 3rd gear to 2nd gear, when the two clutches of the vehicle are in the torque interaction stage, reverse drag in 3rd gear is switched to reverse drag in 2nd gear. Because the torque interaction is that the Offgoing clutch decreases linearly at a certain slope, that is, ramps down, while the Oncoming clutch ramps up, that is, the torque of the Offgoing clutch decreases at a certain slope, and the torque of the Oncoming clutch increases at a certain slope. Both clutches ramp at the same time, so the gear switching is a gradual transition, and this process will not produce any jerking shock, such as Figure 2 The meshing of the gears involved in reverse gear 2 is shown in the figure on the left, circle 2. The large gear represents the actively rotating component, and the other gears represent the passively rotating components. The offgoing clutch in this case can be the odd-numbered clutch corresponding to 3rd gear, and the oncoming clutch can be the even-numbered clutch corresponding to 2nd gear.

[0052] The third stage: Entering the speed control stage from 3rd gear to 2nd gear, when it is detected that the driver has stepped on the accelerator, the gear is switched from 2nd gear to 3rd gear active, that is, the engine torque is transmitted to the large gear and wheel end through the 3rd gear related gear; in this stage, the offgoing clutch, that is, the odd clutch, is more likely to cause the over-Lash point and noise caused by the reversal of the transmission system during the process of power transmission; the meshing condition of the 3rd gear related gear is as follows Figure 3 As shown in the figure, the large gear represents the active rotating parts, and the other gears represent the passive rotating parts. When transitioning from the second stage to the third stage, the gear reversal occurs at the lightning point in the figure, which is the jerky impact generated at this place.

[0053] The fourth stage: from 3rd gear active to 2nd gear active, the oncoming clutch ramp increases and the offgoing clutch ramp decreases. Similar to the second stage, the gear reversal is a gradual transition and will not cause any problems. At this time, the oncoming clutch ramp increases at a relatively high rate, which can quickly transmit the engine torque. Since the speed of 2nd gear is higher than that of 3rd gear, in order to ensure the power response of the vehicle, the wheel end torque of 3rd gear will be greater; the meshing conditions of the relevant gears are as follows Figure 4 As shown, the large gear represents the active rotating component, and the other gears represent the passive rotating components. When transitioning from the third stage to the fourth stage, all gears are reversed, but the left and right sides are reversed alternately, so this reversal will not produce any setbacks or noise.

[0054] Therefore, the present invention provides a method and device for controlling acceleration by pressing the accelerator during vehicle downshifting. During the process of vehicle downshifting and acceleration, the Offgoing clutch currently in an engaged state is controlled to quickly increase from the current torque (first initial torque). When it rises to near the torque corresponding to the Lash point corresponding to the vehicle (first target torque), the torque of the Offgoing clutch is controlled to increase in the form of a parabola based on a parabolic instruction to the torque indicated by the parabolic instruction, thereby smoothly passing the Lash point corresponding to the vehicle and avoiding the problem of vehicle jerking when accelerating during the downshifting process; and when it is detected that the current torque of the Offgoing clutch is the torque indicated by the parabolic instruction, the torque of the Offgoing clutch is controlled to increase linearly, which can avoid noise during the vehicle's downshifting and acceleration process.

[0055] See also Figure 5 , shows a flow chart of a method for controlling the acceleration of a vehicle during a downshift by pressing the accelerator provided by an embodiment of the present invention, wherein the method for controlling the acceleration of a vehicle during a downshift by pressing the accelerator is applied to a gearbox. Figure 6 As shown, the accelerator pedal acceleration control method during vehicle downshifting specifically includes the following steps:

[0056] S501: When a downshift request is received during vehicle coasting, the torque of the offgoing clutch is controlled to be maintained at a first initial torque, so as to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

[0057] During the specific execution of step S501, when the transmission detects a downshift request while the vehicle is coasting, the torque of the clutch currently in the engaged state (for ease of distinction, the clutch currently in the engaged state is referred to as the offgoing clutch) can be controlled to maintain the torque corresponding to the current gear of the vehicle (for ease of distinction, the torque corresponding to the current gear of the vehicle is referred to as the first initial torque) to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

[0058] S502: During vehicle downshifting, when it is detected that the driver has stepped on the accelerator, the offgoing clutch is controlled to increase the torque from the first initial torque to the first target torque, and the oncoming clutch is controlled to decrease the torque from the second initial torque to the second target torque.

[0059] In the embodiment of the present application, because the torque corresponding to the Lash point of different vehicles is different, generally around 9-15 Nm, for each type of vehicle, a torque smaller than the Lash point of the vehicle can be set (for the sake of distinction, the torque set smaller than the Lash point of the vehicle is referred to as the first target torque) to prevent the vehicle from directly passing through the Lash point of the vehicle during downshifting and acceleration.

[0060] During the specific execution of step S502, during the vehicle downshifting process, the transmission can detect in real time whether the driver has stepped on the accelerator through the transmission controller. When it is detected that the driver has stepped on the accelerator, the transmission sends a corresponding instruction to the hydraulic system through its own control unit to control the hydraulic system to send a corresponding torque increase instruction carrying the first target torque to the offgoing clutch, so that when the offgoing clutch receives the corresponding torque increase instruction, it controls its own torque to increase linearly based on the torque increase instruction until it reaches the first target torque indicated by the torque increase instruction, thereby avoiding the vehicle directly passing through the vehicle's Lash point during the downshifting acceleration process.

[0061] In the embodiment of the present application, when it is detected that the driver has stepped on the accelerator, the transmission also controls the torque of the oncoming clutch to drop from the second initial torque to the second target torque through its own control unit.

[0062] The first initial torque is the torque of the offgoing clutch corresponding to the gear position of the vehicle before downshifting, and the second initial torque is the torque of the oncoming clutch corresponding to the gear position of the vehicle before downshifting.

[0063] S503: When it is detected that the current torque of the Offgoing clutch is the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls its own torque to rise in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction.

[0064] The torque indicated by the parabola command is greater than the torque corresponding to the Lash point corresponding to the vehicle.

[0065] During the specific execution of step S503, the torque of the Offgoing clutch is detected in real time. When it is detected that the current torque of the Offgoing clutch is the first target torque, it means that the current torque of the Offgoing clutch is already near the torque corresponding to the Lash point of the vehicle. At this time, the transmission can send corresponding instructions to the hydraulic system through the transmission control unit to control the hydraulic system to send a parabolic instruction to the Offgoing clutch, so that the Offgoing clutch controls its own torque to rise in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction, thereby achieving a smooth passing of the corresponding Lash point of the vehicle and avoiding the problem of vehicle jerking when accelerating during downshifting.

[0066] S504: When it is detected that the current torque of the Offgoing clutch is the torque indicated by the parabola instruction, the torque of the Offgoing clutch is controlled to increase linearly until the torque of the Offgoing clutch increases linearly to a third target torque.

[0067] During the specific execution of step S504, the torque of the Offgoing clutch is detected in real time. When it is detected that the current torque of the Offgoing clutch is the torque indicated by the parabolic instruction, the transmission can control the torque of the Offgoing clutch to rise linearly through the transmission control unit until the torque of the Offgoing clutch rises linearly to the third target torque.

[0068] In this embodiment of the present application, to ensure that the offgoing clutch transmits sufficient torque, it is necessary to ensure that the torque of the offgoing clutch is greater than the third target torque. This ensures that the engine speed does not generate shaft-penetrating noise when passing through the shaft of the oncoming clutch. The specific method for determining the third target torque is as shown in the following formula:

[0069]

[0070] Among them, OncomingTorqA can be Figure 7Wherein, the torque of the Oncoming clutch at A is shown in FIG1 , OncGear2_Ratio is the speed ratio of the gear corresponding to the Oncoming clutch, and OffgGear_Ratio is the speed ratio of the gear corresponding to the Offgoing clutch.

[0071] It should be noted that Figure 7 This is an example diagram of fluctuations in the torque of each clutch, the speed of each clutch, the torque of the engine, and the speed of the engine after applying the vehicle downshift acceleration control method provided by the present application during the downshift acceleration process.

[0072] Among them, OncomingSpeed ​​is the speed of the oncoming clutch, OffgoingSpeed ​​is the speed of the offgoing clutch, EngineSpeed ​​is the speed of the engine, OncomingTorq is the torque of the oncoming clutch, OffgoingTorq is the torque of the offgoing clutch, and EngineTorqueLimitRequest is the torque of the engine.

[0073] The present application provides a method for controlling acceleration by pressing the accelerator during vehicle downshifting, which is applied to a transmission. During the vehicle downshifting process, when it is detected that the driver has pressed the accelerator, the offgoing clutch is controlled to increase from a first initial torque to a first target torque, and the torque of the oncoming clutch is controlled to decrease from a second initial torque to a second target torque; when it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque instruction is sent to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction; when it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque instruction is sent to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction; When the torque indicated by the parabola instruction is less than the torque of the Offgoing clutch, the torque of the Offgoing clutch is controlled to rise linearly until the torque of the Offgoing clutch rises linearly to the second target torque, wherein the Offgoing clutch is the clutch that is currently in the engaged state; the Oncoming clutch is the clutch that is currently in the non-engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear position of the vehicle before downshifting; the second initial torque is the torque of the Oncoming clutch corresponding to the gear position of the vehicle before downshifting; the first target torque is less than the torque corresponding to the Lash point corresponding to the vehicle; the torque indicated by the parabola instruction is greater than the torque corresponding to the Lash point corresponding to the vehicle. The technical solution provided by the present invention is that during the process of vehicle downshifting and acceleration, the Offgoing clutch currently in the engaged state is controlled to quickly increase from the current torque (first initial torque). When it rises to near the torque corresponding to the Lash point corresponding to the vehicle (first target torque), the torque of the Offgoing clutch is controlled to increase in the form of a parabola based on the parabolic instruction to the torque indicated by the parabolic instruction, thereby smoothly passing the Lash point corresponding to the vehicle and avoiding the problem of vehicle jerking when accelerating during the downshifting process; and when it is detected that the current torque of the Offgoing clutch is the torque indicated by the parabolic instruction, the torque of the Offgoing clutch is controlled to increase linearly, which can avoid noise during the vehicle's downshifting and acceleration process.

[0074] See also Figure 8 , shows a flow chart of a method for controlling the acceleration of a vehicle during a downshift by pressing the accelerator provided by an embodiment of the present application, wherein the method for controlling the acceleration of a vehicle during a downshift by pressing the accelerator is applied to Figure 6 For the transmission shown in FIG, the accelerator pedal acceleration control method during the vehicle downshift process specifically includes the following steps:

[0075] S801: When a downshift request is received during vehicle coasting, the torque of the offgoing clutch is controlled to be maintained at a first initial torque, so as to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

[0076] S802: During vehicle downshifting, when it is detected that the driver has stepped on the accelerator, the offgoing clutch is controlled to increase the torque from a first initial torque to a first target torque, and the oncoming clutch is controlled to decrease the torque from a second initial torque to a second target torque.

[0077] Among them, the Offgoing clutch is the clutch that is currently in the engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear position of the vehicle before downshifting; the first target torque is less than the torque corresponding to the Lash point corresponding to the vehicle; the Oncoming clutch is the clutch that is currently in the non-engaged state; the second initial torque is the torque of the Oncoming clutch corresponding to the gear position of the vehicle before downshifting.

[0078] S803: When it is detected that the current torque of the Offgoing clutch is the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls its own torque to rise in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction.

[0079] The torque indicated by the parabola command is greater than the torque corresponding to the Lash point corresponding to the vehicle.

[0080] S804: When it is detected that the current torque of the Offgoing clutch is the torque indicated by the parabola instruction, the torque of the Offgoing clutch is controlled to increase linearly until the torque of the Offgoing clutch increases linearly to the third target torque.

[0081] In the process of specifically executing step S801 to step S804, the specific execution process and implementation principle of step S801 to step S804 are the same as those disclosed in the above-mentioned application. Figure 5 The specific execution process and implementation principle of steps S501 to S504 are the same as those disclosed in the above application. Figure 5 The corresponding parts will not be described here.

[0082] S805: During a vehicle downshift, when it is detected that the driver has stepped on the accelerator, a first torque control request is sent to the engine of the vehicle, so that the engine controls its own torque to maintain at a third initial torque based on the torque control request.

[0083] The third initial torque is the torque of the engine when the first torque control request is received.

[0084] During the specific execution of step S805, when the vehicle is downshifting, the transmission can detect in real time through the transmission controller whether the driver has stepped on the accelerator. When it is detected that the driver has stepped on the accelerator, the transmission sends a first torque control request to the vehicle's engine through its own control unit, so that the engine controls its own torque to maintain at the third initial torque based on the torque control request, thereby allowing the engine speed to increase rapidly.

[0085] S806: When it is detected that the current torque of the Offgoing clutch is the first target torque, a second torque control request is sent to the engine, so that the engine controls its own torque to drop from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then controls the engine torque to slowly increase until it is detected that the engine speed is synchronized with the speed of the Oncoming clutch.

[0086] During the specific execution of step S806, the torque of the Offgoing clutch is detected in real time. When it is detected that the current torque of the Offgoing is the first target torque, it can be determined that the engine speed is close to the speed of the Oncoming clutch at this time. When close to synchronization, in order to ensure smooth synchronization of the engine speed and the Oncoming shaft speed, the torque reduction can be reduced, that is, the transmission can send a second torque control request to the engine through the transmission control unit, so that the engine controls its own torque from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then controls the engine torque to slowly increase until it is detected that the engine speed is synchronized with the speed of the Oncoming clutch.

[0087] S807: When it is detected that the engine speed is synchronized with the speed of the oncoming clutch, the oncoming clutch is controlled to quickly increase from the third target torque to the fourth target torque, and the torque of the offgoing clutch is controlled to quickly decrease from the second target torque to the fifth target torque.

[0088] In an embodiment of the present application, when it is detected that the engine speed is synchronized with the speed of the oncoming clutch, in order to respond to the driver's acceleration demand as quickly as possible, the oncoming clutch can be controlled by the control unit of the transmission to quickly increase the third target torque to the fourth target torque, and the torque of the offgoing clutch can be controlled to quickly decrease from the second target torque to the fifth target torque, thereby improving the power response of the entire vehicle.

[0089] Corresponding to the above-mentioned embodiment of the present invention disclosed a method for controlling the acceleration during vehicle downshifting by pressing the accelerator, Figure 9The embodiment of the present invention further provides a schematic structural diagram of a vehicle downshift acceleration control device. The vehicle downshift acceleration control device is applied to a transmission. The vehicle downshift acceleration control device comprises:

[0090] The first control unit 91 is configured to control the offgoing clutch to increase its torque from a first initial torque to a first target torque and control the oncoming clutch to decrease its torque from a second initial torque to a second target torque during a vehicle downshift when it is detected that the driver has stepped on the accelerator. The offgoing clutch is a clutch currently in an engaged state. The first initial torque is the torque of the offgoing clutch corresponding to the gear position of the vehicle before the downshift. The first target torque is less than the torque corresponding to the corresponding Lash point of the vehicle. The oncoming clutch is a clutch currently in a non-engaged state. The second initial torque is the torque of the oncoming clutch corresponding to the gear position of the vehicle before the downshift.

[0091] The first transmission unit 92 is configured to, when detecting that the current torque of the offgoing clutch is the first target torque, send a parabolic torque command to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in a parabolic manner to the torque indicated by the parabolic command based on the parabolic torque command; wherein the torque indicated by the parabolic command is greater than the torque corresponding to the corresponding Lash point of the vehicle;

[0092] The second control unit 93 is configured to control the torque of the offgoing clutch to increase linearly when it is detected that the current torque of the offgoing clutch is the torque indicated by the parabola instruction, until the torque of the offgoing clutch increases linearly to the third target torque.

[0093] The specific principles and execution processes of each unit in the accelerator acceleration control device during vehicle downshifting disclosed in the above embodiment of the present invention are the same as those in the above embodiment of the present invention. Figure 5 The disclosed method for controlling the acceleration during vehicle downshifting by pressing the accelerator pedal is the same as that disclosed in the embodiment of the present invention. Figure 5 The corresponding parts of the disclosed method for controlling the acceleration by pressing the accelerator during the vehicle downshift process will not be described in detail here.

[0094] The present application provides an accelerator pedal acceleration control device during vehicle downshifting, which is applied to a transmission. During the vehicle downshifting process, when it is detected that the driver has stepped on the accelerator, the offgoing clutch is controlled to increase from a first initial torque to a first target torque, and the torque of the oncoming clutch is controlled to decrease from a second initial torque to a second target torque; when it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque instruction is sent to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction; when it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque instruction is sent to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in the form of a parabola to the torque indicated by the parabolic instruction based on the parabolic torque instruction; When the torque indicated by the parabola instruction is less than the torque of the Offgoing clutch, the torque of the Offgoing clutch is controlled to rise linearly until the torque of the Offgoing clutch rises linearly to the second target torque, wherein the Offgoing clutch is the clutch that is currently in the engaged state; the Oncoming clutch is the clutch that is currently in the non-engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear position of the vehicle before downshifting; the second initial torque is the torque of the Oncoming clutch corresponding to the gear position of the vehicle before downshifting; the first target torque is less than the torque corresponding to the Lash point corresponding to the vehicle; the torque indicated by the parabola instruction is greater than the torque corresponding to the Lash point corresponding to the vehicle. The technical solution provided by the present invention is that during the process of vehicle downshifting and acceleration, the Offgoing clutch currently in the engaged state is controlled to quickly increase from the current torque (first initial torque). When it rises to near the torque corresponding to the Lash point corresponding to the vehicle (first target torque), the torque of the Offgoing clutch is controlled to increase in the form of a parabola based on the parabolic instruction to the torque indicated by the parabolic instruction, thereby smoothly passing the Lash point corresponding to the vehicle and avoiding the problem of vehicle jerking when accelerating during the downshifting process; and when it is detected that the current torque of the Offgoing clutch is the torque indicated by the parabolic instruction, the torque of the Offgoing clutch is controlled to increase linearly, which can avoid noise during the vehicle's downshifting and acceleration process.

[0095] Furthermore, the vehicle downshift acceleration control device disclosed in the present application further includes:

[0096] The third control unit is configured to control the torque of the offgoing clutch to maintain at a first initial torque when a downshift request is received during the coasting process of the vehicle, so as to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

[0097] Furthermore, the vehicle downshift acceleration control device disclosed in the present application further includes:

[0098] The second sending unit is used to send a first torque control request to the vehicle's engine, so that the engine controls its own torque to maintain at a third initial torque based on the torque control request; wherein the third initial torque is the torque of the engine when receiving the first torque control request.

[0099] Furthermore, the vehicle downshift acceleration control device disclosed in the present application further includes:

[0100] The third sending unit is used to send a second torque control request to the engine, so that the engine controls its own torque to drop from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then controls the engine torque to slowly increase until it is detected that the engine speed is synchronized with the speed of the oncoming clutch.

[0101] Furthermore, the vehicle downshift acceleration control device disclosed in the present application further includes:

[0102] The fourth control unit is used to control the oncoming clutch to quickly increase from the third target torque to the fourth target torque, and control the torque of the offgoing clutch to quickly decrease from the second target torque to the fifth target torque when it is detected that the engine speed is synchronized with the speed of the oncoming clutch.

[0103] Each embodiment in this specification is described in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple. For relevant parts, refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without making any creative efforts.

[0104] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0105] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one 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 invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

[0106] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for controlling acceleration during vehicle downshifting by pressing the accelerator pedal, characterized in that: Applied to a gearbox, the method comprises: During a vehicle downshift, when it is detected that the driver has stepped on the accelerator, the offgoing clutch is controlled to increase its torque from a first initial torque to a first target torque, and the oncoming clutch is controlled to decrease its torque from a second initial torque to a second target torque; wherein the offgoing clutch is a clutch currently in an engaged state; the first initial torque is the torque of the offgoing clutch corresponding to the gear position of the vehicle before the downshift; the first target torque is less than the torque corresponding to the corresponding Lash point of the vehicle; the oncoming clutch is a clutch currently in a non-engaged state; and the second initial torque is the torque of the oncoming clutch corresponding to the gear position of the vehicle before the downshift; When it is detected that the current torque of the offgoing clutch is the first target torque, a parabolic torque command is sent to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in a parabolic form to the torque indicated by the parabolic command based on the parabolic torque command; wherein the torque indicated by the parabolic command is greater than the torque corresponding to the corresponding Lash point of the vehicle; When it is detected that the current torque of the offgoing clutch is the torque indicated by the parabola instruction, the torque of the offgoing clutch is controlled to increase linearly until the torque of the offgoing clutch increases linearly to a third target torque.

2. The method according to claim 1, characterized in that Before the vehicle downshifts, the method further comprises: During vehicle coasting, when a downshift request is received, the torque of the offgoing clutch is controlled to be maintained at the first initial torque, so as to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

3. The method according to claim 1, characterized in that During the process of downshifting the vehicle, when it is detected that the driver has stepped on the accelerator, the method further includes: A first torque control request is sent to an engine of the vehicle, so that the engine controls its own torque to maintain at a third initial torque based on the torque control request; wherein the third initial torque is the torque of the engine when the first torque control request is received.

4. The method according to claim 3, characterized in that When it is detected that the current torque of the offgoing clutch is the first target torque, the method further includes: A second torque control request is sent to the engine, so that the engine controls its own torque to drop from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then controls the torque of the engine to slowly increase until it is detected that the engine speed is synchronized with the speed of the oncoming clutch.

5. The method according to claim 4, characterized in that The method further comprises: When it is detected that the engine speed is synchronized with the speed of the oncoming clutch, the oncoming clutch is controlled to quickly increase from the third target torque to a fourth target torque, and the torque of the offgoing clutch is controlled to quickly decrease from the second target torque to a fifth target torque.

6. A vehicle acceleration control device for stepping on the accelerator during downshifting, characterized in that: Applied to a gearbox, the device comprises: a first control unit configured to control, during a vehicle downshift, when it is detected that the driver has stepped on the accelerator, to control the torque of the offgoing clutch to increase from a first initial torque to a first target torque, and to control the torque of the oncoming clutch to decrease from a second initial torque to a second target torque; wherein the offgoing clutch is a clutch currently in an engaged state; the first initial torque is the torque of the offgoing clutch corresponding to the gear position of the vehicle before the downshift; the first target torque is less than the torque corresponding to the corresponding Lash point of the vehicle; the oncoming clutch is a clutch currently in a non-engaged state; and the second initial torque is the torque of the oncoming clutch corresponding to the gear position of the vehicle before the downshift; a first transmission unit, configured to, when detecting that the current torque of the offgoing clutch is the first target torque, transmit a parabolic torque command to the offgoing clutch, so that the offgoing clutch controls its own torque to increase in a parabolic manner to the torque indicated by the parabolic command based on the parabolic torque command; wherein the torque indicated by the parabolic command is greater than the torque corresponding to the corresponding Lash point of the vehicle; The second control unit is configured to control the torque of the offgoing clutch to increase linearly when it is detected that the current torque of the offgoing clutch is the torque indicated by the parabola instruction, until the torque of the offgoing clutch increases linearly to a third target torque.

7. The device according to claim 6, characterized in that The device further comprises: The third control unit is configured to control the torque of the offgoing clutch to maintain at the first initial torque when a downshift request is received during vehicle coasting, so as to control the vehicle to slowly downshift from a current gear to a target gear indicated by the downshift request.

8. The device according to claim 6, characterized in that The device further comprises: The second sending unit is used to send a first torque control request to the engine of the vehicle, so that the engine controls its own torque to maintain at a third initial torque based on the torque control request; wherein the third initial torque is the torque of the engine when receiving the first torque control request.

9. The device according to claim 8, characterized in that The device further comprises: a third sending unit, configured to send a second torque control request to the engine, so that the engine controls its own torque to drop from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then controls the torque of the engine to slowly increase until it is detected that the engine speed is synchronized with the speed of the oncoming clutch.

10. The device according to claim 9, characterized in that The device further comprises: The fourth control unit is used to control the oncoming clutch to quickly increase from the third target torque to the fourth target torque, and to control the torque of the offgoing clutch to quickly decrease from the second target torque to the fifth target torque when it is detected that the speed of the engine is synchronized with the speed of the oncoming clutch.

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