CN116025704A - Acceleration control method and device for stepping on accelerator in vehicle downshift process - Google Patents

Abstract

The application provides a method and a device for controlling acceleration of an accelerator pedal in a vehicle downshifting process, wherein in the acceleration process of the accelerator pedal in the downshifting process, an Offgoing clutch is controlled to rise from a first initial torque to a first target torque, and the torque of the Oncoming clutch is controlled to fall from a second initial torque to a second target torque; when the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic instruction in a parabolic mode based on the parabolic torque instruction; and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic command, controlling the torque straight line of the off-going clutch to rise until the torque straight line of the off-going clutch reaches the third target torque. According to the method and the device, the power response can be ensured in the acceleration process of stepping on the accelerator during the vehicle downshifting, and the generation of setbacks and noise is avoided.

Description

Acceleration control method and device for stepping on accelerator in vehicle downshift process

Technical Field

The invention relates to the technical field of vehicle control, in particular to a method and a device for controlling accelerator stepping and acceleration in a vehicle downshift process.

Background

While a vehicle frequently experiences various gear shifting conditions during a vehicle gear shifting process, if the intention of the driver changes, impact jerk or Clunk noise is easily caused, for example, the vehicle is coasting down, the driver's own demand is decelerating, but if the driver steps on the accelerator during the down-shift process, the driver's demand becomes accelerating, and jerk or Clunk noise is generated.

In the prior art, a torque limiting strategy can be adopted, and the problem that the Clink noise is generated when a driver steps on an accelerator in the process of downshifting can be solved. But this approach still suffers from the problem of a setback.

Disclosure of Invention

Based on the defects of the prior art, the application provides a method and a device for controlling accelerator stepping in the vehicle downshifting process, aiming at avoiding the generation of setbacks and noise in the accelerator stepping acceleration process when the vehicle downshifts.

In order to achieve the above object, the present application provides the following technical solutions:

the first aspect of the invention discloses a method for controlling acceleration of a stepping accelerator in a vehicle downshift process, which is applied to a gearbox, and comprises the following steps:

in the process of vehicle downshifting, when the driver is detected to step on the accelerator, controlling the clutch to rise from a first initial torque to a first target torque, and controlling the torque of the Oncoming clutch to fall from a second initial torque to a second target torque; the clutch is in a currently engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the coupling clutch is a clutch in a non-engagement state at present; the second initial torque is the torque of the coupling clutch corresponding to the gear of the vehicle before the downshift;

When the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic instruction in a parabolic manner based on the parabolic torque instruction; the torque indicated by the parabolic instruction is larger than the torque corresponding to the Lash point corresponding to the vehicle;

and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque of the off-going clutch to be linearly increased until the torque of the off-going clutch is linearly increased to a third target torque.

Optionally, before the vehicle downshifts, the method further includes:

during the coasting of the vehicle, when a downshift request is received, the torque of the off clutch is controlled to be maintained at the first initial torque to control the vehicle to slowly downshift from a current gear to a target gear indicated by the downshift request.

Optionally, during the vehicle downshift, when it is detected that the driver steps on the accelerator, the method further includes:

Transmitting a first torque control request to an engine of the vehicle to cause the engine to control self torque to be maintained at a third initial torque based on the torque control request; wherein the third initial torque is a torque of the engine at the time of receiving the first torque control request.

Optionally, when detecting that the current torque of the Offgoing clutch is the first target torque, the method further includes:

and sending a second torque control request to the engine, so that the engine controls the self 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 rise until the rotational speed of the engine is detected to be synchronous with the rotational speed of the Oncoming clutch.

Optionally, the method further comprises:

when it is detected that the rotational speed of the engine is synchronized with the rotational speed of the Oncoming clutch, the Oncoming clutch is controlled to quickly rise from the third target torque to a fourth target torque, and the torque of the Offgoing clutch is controlled to quickly fall from the second target torque to a fifth target torque.

A second aspect of the present application discloses a vehicle downshift in-process accelerator acceleration control device, applied to the gearbox, said device includes:

the first control unit is used for controlling the clutch to rise from the first initial torque to the first target torque and controlling the torque of the Oncoming clutch to drop from the second initial torque to the second target torque when the driver is detected to step on the accelerator in the process of vehicle downshift; the clutch is in a currently engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the coupling clutch is a clutch in a non-engagement state at present; the second initial torque is the torque of the coupling clutch corresponding to the gear of the vehicle before the downshift;

the first sending unit is used for sending a parabolic torque instruction to the Offgoing clutch when the current torque of the Offgoing clutch is detected to be the first target torque, so that the Offgoing clutch can control the self torque to rise to the torque indicated by the parabolic instruction in a parabolic form based on the parabolic torque instruction; the torque indicated by the parabolic instruction is larger than the torque corresponding to the Lash point corresponding to the vehicle;

And the second control unit is used for controlling the torque straight line of the off-going clutch to rise until the torque straight line of the off-going clutch rises to a third target torque when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction.

Optionally, the apparatus further includes:

and the third control unit is used for controlling the torque of the off clutch to be maintained at the first initial torque when a downshift request is received in the process of vehicle coasting so as to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

Optionally, the apparatus further includes:

a second transmitting unit configured to transmit a first torque control request to an engine of the vehicle so that the engine controls the self torque to be maintained at a third initial torque based on the torque control request; wherein the third initial torque is a torque of the engine at the time of receiving the first torque control request.

Optionally, the apparatus further includes:

and the third sending unit is used for sending a second torque control request to the engine so that the sender controls the self 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 rise until the rotation speed of the engine is detected to be synchronous with the rotation speed of the coupling clutch.

Optionally, the apparatus further includes:

and a fourth control unit configured to control the Oncoming clutch to quickly rise from the third target torque to a fourth target torque and control the torque of the Offgoing clutch to quickly fall from the second target torque to a fifth target torque when it is detected that the rotational speed of the engine is synchronized with the rotational speed of the Oncoming clutch.

The application provides a method and a device for controlling acceleration of an accelerator pedal in a vehicle downshift process, which are applied to a gearbox, and when a driver is detected to step on the accelerator pedal in the vehicle downshift process, an Offgoing clutch is controlled to rise from a first initial torque to a first target torque, and the torque of an Oncoming clutch is controlled to fall from a second initial torque to a second target torque; when the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic instruction in a parabolic mode based on the parabolic torque instruction; when the current torque of the off clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque straight line of the off clutch to rise until the torque straight line of the off clutch rises to the second target torque, wherein the off clutch is the clutch in the currently engaged state; the Oncoming clutch is a clutch in a non-engagement state at present; the first initial torque is the torque of an Offgoing clutch corresponding to a gear of the vehicle before the downshift; the second initial torque is the torque of an Oncoming clutch corresponding to the gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the torque indicated by the parabolic command is greater than the torque corresponding to the Lash point corresponding to the vehicle. According to the technical scheme, in the process of vehicle downshift and acceleration, the Offgoing clutch in the engaged state is controlled to rapidly rise from the current torque (the first initial torque), and when the Offgoing clutch rises to the vicinity of the torque corresponding to the corresponding Lash point of the vehicle (the first target torque), the torque of the Offgoing clutch is controlled to rise to the torque indicated by the parabolic instruction in a parabolic manner based on the parabolic instruction, so that the smooth Lash point corresponding to the vehicle is dropped is realized, and the problem of the jerk and the frustration generated when the vehicle accelerates in the downshift process is avoided; and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque of the off-going clutch to linearly rise, so that noise can be avoided in the process of downshifting and accelerating the vehicle.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present application, and that other drawings may be obtained according to the provided drawings without inventive effort to a person skilled in the art.

FIG. 1 is a schematic illustration of torque of various clutches, and fluctuations in engine speed and torque during a vehicle downshift acceleration using a torque limiting strategy as provided in the prior art;

FIG. 2 is a schematic diagram of the prior art providing a gear engagement of the gears and odd-even clutches after the vehicle enters 3-speed down to 2-speed control;

FIG. 3 is a schematic diagram of the meshing of the gears and even-odd clutches after detecting that the driver steps on the throttle in a speed regulation control phase of the vehicle from 3 to 2 in accordance with the prior art;

FIG. 4 is a schematic diagram of the gear engagement of the gears and the odd-even clutch after a vehicle is driven from 3 to 2 in accordance with the prior art;

FIG. 5 is a schematic flow chart of a method for controlling acceleration of a throttle during a downshift of a vehicle according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a transmission according to an embodiment of the present invention;

FIG. 7 is a graph showing the torque of each clutch, the rotational speed of each clutch, the torque of the engine and the rotational speed of the engine after applying the vehicle downshift acceleration control method according to the embodiment of the present invention during downshift acceleration;

FIG. 8 is a flowchart of another method for controlling acceleration of a vehicle during a downshift according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a device for controlling acceleration of a pedal in a vehicle during a downshift according to an embodiment of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The term "including" and variations thereof as used herein are intended to be open-ended, i.e., including, but not limited to. The term "based on" is 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"; the term "some embodiments" means "at least some embodiments. Related definitions of other terms will be given in the description below.

It should be noted that the terms "first," "second," and the like in this disclosure are merely used for distinguishing between different devices, modules, or units and not for limiting the order or interdependence of the functions performed by these devices, modules, or units.

It should be noted that references to "one" or "a plurality" in this disclosure are intended to be illustrative rather than limiting, and those of ordinary skill in the art will appreciate that "one or more" is intended to be interpreted as "one or more" unless the context clearly indicates otherwise.

As can be seen from the above background art, in the prior art, a torque limiting strategy can be adopted to solve the problem of Clunk or Clunk noise generated when the driver steps on the accelerator during the downshift. The specific process of the torsion limiting strategy can be as follows: releasing pressure below a corresponding Lash point of the vehicle by controlling the Oncoming clutch, as in the A stage in FIG. 1; while requesting torque limiting of the engine management system (Engine Management System, EMS), when detecting that the engine speed exceeds the speed of the Oncoming clutch, the engine torque is redirected to resume while controlling the Oncoming clutch torque Ramp up, as shown in stage B of fig. 1. However, this control approach typically has two problems. The clutch with the clutch being engaged is the clutch which is currently in the engaged state, and the clutch with the clutch being engaged is the clutch which is currently in the disengaged state. Fig. 1 is a graph showing an example of fluctuation of torque of each clutch, rotational speed of each clutch, torque of an engine, and rotational speed of the engine after applying a torque limiting strategy during upshift.

Wherein OncomingSpeed is the rotational Speed of the Oncoming clutch, offgoingSpeed is the rotational Speed of the Offgoingclutch, engine Speed is the rotational Speed of the Engine, oncomingTorr is the torque of the Oncoming clutch, offgoingTorr is the torque of the Offgoingclutch, and E is the torque of the Engine.

Problem 1: the EMS is limited in torsion, and the torque of the Oncoming clutch is below the corresponding Lash point of the vehicle, so that no power is output after the accelerator is stepped on, and the power response of the vehicle is slow; problem 2: while in B phase, the Oncoming clutch is ascending at a certain slope, namely Ramp, the actual required torque of the engine is very large, and because the driver steps on the accelerator, the torque of the Oncoming clutch needs to be faster at the certain slope to respond to the torque requirement in B phase, but the problem of reversing the transmission system and passing the Lash point is involved, and the problems of the Clunk noise are easy to occur.

In order to better understand the above problems related to driveline commutation, the problem of passing the Lash point, leading to the ease of clunks and Clunk noise, a corresponding example analysis is performed below.

For example, when the current vehicle is in a 3-gear to 2-gear downshift process, the driver steps on the accelerator, and the transmission process of the transmission system and the gear in the whole process can be divided into the following four stages.

The first stage: 3-gear reverse towing, 3-gear sliding is always performed before 3-gear is shifted down to 2-gear, so that 3-gear reverse towing is always performed at this stage.

And a second stage: and 2-gear reverse towing, wherein after the control of 3-gear down to 2-gear is entered, when two clutches of the vehicle are in a torque interaction stage, the 3-gear reverse towing is converted into 2-gear reverse towing. Because torque interaction is that the Offgoing clutch descends with a certain slope, namely Ramp descends, and the Oncoming clutch Ramp ascends, namely the torque of the Offgoing clutch descends with a certain slope, the torque of the Oncoming clutch ascends with a certain slope, and the two clutches simultaneously Ramp, the reversing of the gears is in a gradual transition mode, no jerk impact is generated in the process, as shown in fig. 2, the meshing condition of the 2-gear reverse-dragging related gears is shown as a left ring 2 in the figure, the large cake wheel represents an actively rotating component, and the other gears represent passive rotating components. The clutch with offset may be an odd clutch corresponding to 3 gear, and the clutch with Oncoming may be an even clutch corresponding to 2 gear.

And a third stage: in a speed regulation control stage of 3-gear to 2-gear, when the driver is detected to step on the accelerator, the speed is changed from 2-gear to 3-gear initiative, namely the engine torque is transmitted to the pancake teeth and the wheel end through the 3-gear related gear; the off-going clutch at this stage, namely the odd clutch, is relatively easy to appear because of the drive train commutating and bring to cross the dash point and pause and noise in the course of laminating and transmitting power; the meshing condition of the 3-gear driving related gear is shown in fig. 3, the large cake wheel represents a driving rotating component, the other gears represent passive rotating components, the transition is from the second stage to the third stage, and the gear reversing is carried out at the lightning position in the figure, namely the bump impact is generated at the position.

Fourth stage: the 3-gear driving mode is adopted to 2-gear driving mode, namely the on-coming clutch Ramp is lifted and the off-going clutch Ramp is lowered, and in a second stage, the gear reversing is in slow transition and does not cause problems, and at the moment, the lifting speed of the on-coming clutch Ramp is relatively high, so that the torque of an engine can be quickly transmitted, and the 2-gear rotating speed is higher than the 3-gear rotating speed, so that the wheel end torque of the 3-gear is higher in order to ensure the power response of a vehicle; the meshing condition of the related gears is shown in fig. 4, the large cake wheel represents a part which rotates actively, the other gears represent a part which rotates passively, the transition from the third stage to the fourth stage is realized, all the gears are reversed, but the left side and the right side are alternately carried out, and therefore, no setback and noise are generated in the reversing.

Therefore, the invention provides a method and a device for controlling accelerator stepping acceleration in the vehicle downshifting process, wherein during the vehicle downshifting acceleration process, the current torque (first initial torque) of the Offgoing clutch in an engaged state is controlled to be quickly increased, and when the current torque is increased to the vicinity of the torque corresponding to the corresponding Lash point of the vehicle (first target torque), the torque of the Offgoing clutch is controlled to be increased to the torque indicated by the parabolic instruction in a parabolic manner based on the parabolic instruction, so that the smooth Lash point corresponding to the vehicle is dropped is realized, and the problem of jerk generated when the vehicle accelerates in the downshifting process is avoided; and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, the torque of the off-going clutch is controlled to be directly increased, so that noise can be avoided in the process of downshifting and accelerating the vehicle.

Referring to fig. 5, a flow chart of a method for controlling acceleration of a vehicle during a downshift according to an embodiment of the present invention is shown, where the method for controlling acceleration of the vehicle during a downshift is applied to a gearbox, and the gearbox is shown in fig. 6, and the method for controlling acceleration of the vehicle during a downshift specifically includes the following steps:

S501: during coasting of the vehicle, when a downshift request is received, torque of the off clutch is controlled to be maintained at a first initial torque to control the vehicle to slowly downshift from the current gear to a target gear indicated by the downshift request.

In the process of specifically executing step S501, during the coasting of the vehicle, when the transmission detects a downshift request, the torque of the clutch currently in the engaged state (for convenience of distinction, the clutch currently in the engaged state is referred to as an off-going clutch) may be controlled to be maintained at the torque corresponding to the current gear of the vehicle (for convenience of distinction, the torque corresponding to the current gear of the vehicle is referred to as 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.

S502: during a downshift of the vehicle, when it is detected that the driver steps on the accelerator, the Offgoing clutch is controlled to rise from a first initial torque to a first target torque, and the Oncoming clutch is controlled to fall from a second initial torque to a second target torque.

In the embodiment of the application, because the torques corresponding to the Lash points of different vehicles are different and are approximately 9-15Nm accessory, for each type of vehicle, a torque smaller than the Lash point of the vehicle (for convenience of distinguishing, the set torque smaller than the Lash point of the vehicle is called a first target torque), so that the vehicle is prevented from directly passing through the Lash point of the vehicle in the process of downshifting and accelerating.

In the process of specifically executing step S502, during the vehicle downshift, the gearbox may detect in real time whether the driver steps on the accelerator through the controller of the gearbox, and when detecting that the driver steps on the accelerator, the gearbox sends a corresponding instruction to the hydraulic system through its own control unit, so as to control the hydraulic system to send a corresponding torque rising instruction carrying the first target torque to the off clutch, so that when the off clutch receives the corresponding torque rising instruction, the off clutch controls its own torque to rise directly based on the torque rising instruction until rising to the first target torque indicated by the torque rising instruction, and it is able to avoid the vehicle from directly passing through the Lash point of the vehicle during the downshift acceleration.

In the embodiment of the application, when the driver is detected to step on the accelerator, the gearbox also controls the torque of the Oncoming clutch to drop from the second initial torque to the second target torque through the control unit of the gearbox.

The first initial torque is the torque of an off-going clutch corresponding to the gear of the vehicle before the downshift, and the second initial torque is the torque of an on-going clutch corresponding to the gear of the vehicle before the downshift.

S503: and when the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque command is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic command in a parabolic manner based on the parabolic torque command.

The torque indicated by the parabolic instruction is larger than the torque corresponding to the Lash point corresponding to the vehicle.

In the specific execution process of step S503, the torque of the Offgoing clutch is detected in real time, when the detected current torque of the Offgoing clutch is the first target torque, it is indicated 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 gearbox may send a corresponding instruction to the hydraulic system through the gearbox control unit, so as to control the hydraulic system to send a parabolic instruction to the Offgoing clutch, so that the Offgoing clutch controls the torque of the Offgoing clutch to rise to the torque indicated by the parabolic instruction in a parabolic manner based on the parabolic torque instruction, thereby realizing a smooth Lash point corresponding to the vehicle, and avoiding the jerk problem generated when the vehicle accelerates in the downshift process.

S504: and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque straight line of the off-going clutch to rise until the torque straight line of the off-going clutch rises to the third target torque.

In the specific execution of step S504, the torque of the off-going clutch is detected in real time, and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic command, the gearbox may control the torque line of the off-going clutch to rise through the gearbox control unit until the torque line of the off-going clutch rises to the third target torque.

In the embodiment of the application, the torque of the off clutch is ensured to be above the third target torque, so that the engine rotating speed can be ensured not to generate through-shaft noise when passing through the shaft of the on clutch. The specific determination mode of the third target torque is shown in the following formula:

the Oncoming torqa may be torque of the Oncoming clutch at a in fig. 7, the Oncoming gear2_ratio is a speed Ratio corresponding to a gear corresponding to the Oncoming clutch, and the offg gear_ratio is a speed Ratio corresponding to a gear corresponding to the Offgoing clutch.

Fig. 7 is a graph showing an example of fluctuation of torque of each clutch, rotational speed of each clutch, torque of the engine, and rotational speed of the engine after the vehicle downshift acceleration control method provided in the present application is applied during downshift acceleration.

Wherein OncomingSpeed is the rotational Speed of the Oncoming clutch, offgoingSpeed is the rotational Speed of the Offgoingclutch, engine Speed is the rotational Speed of the Engine, oncomingTorr is the torque of the Oncoming clutch, offgoingTorr is the torque of the Offgoingclutch, and E is the torque of the Engine.

The application provides a control method for accelerating accelerator stepping in a vehicle downshifting process, which is applied to a gearbox, and is used for controlling an Offgoing clutch to rise from a first initial torque to a first target torque and controlling the torque of an Oncoming clutch to fall from a second initial torque to a second target torque when the accelerator stepping of a driver is detected in the vehicle downshifting process; when the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic instruction in a parabolic mode based on the parabolic torque instruction; when the current torque of the off clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque straight line of the off clutch to rise until the torque straight line of the off clutch rises to the second target torque, wherein the off clutch is the clutch in the currently engaged state; the Oncoming clutch is a clutch in a non-engagement state at present; the first initial torque is the torque of an Offgoing clutch corresponding to a gear of the vehicle before the downshift; the second initial torque is the torque of an Oncoming clutch corresponding to the gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the torque indicated by the parabolic command is greater than the torque corresponding to the Lash point corresponding to the vehicle. According to the technical scheme, in the process of vehicle downshift and acceleration, the Offgoing clutch in the engaged state is controlled to rapidly rise from the current torque (the first initial torque), and when the Offgoing clutch rises to the vicinity of the torque corresponding to the corresponding Lash point of the vehicle (the first target torque), the torque of the Offgoing clutch is controlled to rise to the torque indicated by the parabolic instruction in a parabolic manner based on the parabolic instruction, so that the smooth Lash point corresponding to the vehicle is dropped is realized, and the problem of the jerk and the frustration generated when the vehicle accelerates in the downshift process is avoided; and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, the torque of the off-going clutch is controlled to be directly increased, so that noise can be avoided in the process of downshifting and accelerating the vehicle.

Referring to fig. 8, a flow chart of a method for controlling acceleration of a vehicle during a downshift according to an embodiment of the present application is shown, where the method for controlling acceleration of the vehicle during a downshift is applied to a gearbox shown in fig. 6, and the method for controlling acceleration of the vehicle during a downshift specifically includes the following steps:

s801: during coasting of the vehicle, when a downshift request is received, torque of the off clutch is controlled to be maintained at a first initial torque to control the vehicle to slowly downshift from the current gear to a target gear indicated by the downshift request.

S802: during a downshift of the vehicle, when it is detected that the driver steps on the accelerator, the Offgoing clutch is controlled to rise from a first initial torque to a first target torque, and the Oncoming clutch is controlled to fall from a second initial torque to a second target torque.

The clutch is in an engaged state at present; the first initial torque is the torque of an Offgoing clutch corresponding to a gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the Oncoming clutch is a clutch in a non-engagement state at present; the second initial torque is the torque of the Oncoming clutch corresponding to the gear in which the vehicle was located prior to the downshift.

S803: and when the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque command is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic command in a parabolic manner based on the parabolic torque command.

The torque indicated by the parabolic instruction is larger than the torque corresponding to the Lash point corresponding to the vehicle.

S804: and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque straight line of the off-going clutch to rise until the torque straight line of the off-going clutch rises to the third target torque.

In the process of specifically executing steps S801 to S804, the specific execution process and implementation principle of steps S701 to S704 are the same as the specific execution process and implementation principle of steps S501 to S504 in fig. 5 disclosed in the above application, and reference may be made to the corresponding parts in fig. 5 disclosed in the above application, and the details are not repeated here.

S805: during a downshift of the vehicle, 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 to cause the engine to control its own torque to be maintained at a third initial torque based on the torque control request.

Wherein the third initial torque is a torque of the engine when the first torque control request is received.

In the process of specifically executing step S805, during the vehicle downshift, the gearbox may detect in real time whether the driver steps on the accelerator through the controller of the gearbox, and when detecting that the driver steps on the accelerator, the gearbox sends a first torque control request to the engine of the vehicle through its own control unit, so that the engine maintains its own torque at a third initial torque based on the torque control request, and the engine speed may be increased rapidly.

S806: when the current torque of the clutch is detected to be the first target torque, a second torque control request is sent to the engine, so that the engine is controlled 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 the torque of the engine is controlled to slowly rise until the rotation speed of the engine is detected to be synchronous with the rotation speed of the clutch.

In the specific execution process of step S806, the torque of the off clutch is detected in real time, when the current torque of off is detected to be the first target torque, it may be determined that the rotational speed of the engine is close to synchronous with the rotational speed of the on clutch, and when the rotational speed of the engine is close to synchronous with the rotational speed of the on clutch, the torque reduction may be reduced, that is, a second torque control request may be sent to the engine through the gearbox control unit, so that the sender may control the self torque to be reduced from the third initial torque to the torque indicated by the second torque control request based on the second torque control request, and then control the torque of the engine to be slowly increased until the rotational speed of the engine is detected to be synchronous with the rotational speed of the on clutch.

S807: when the rotational speed of the engine is detected to be synchronous with the rotational speed of the Oncoming clutch, the Oncoming clutch is controlled to rapidly rise from the third target torque to the fourth target torque, and the torque of the Offgoing clutch is controlled to rapidly fall from the second target torque to the fifth target torque.

In the embodiment of the application, when the rotational speed of the engine is detected to be synchronous with the rotational speed of the Oncoming clutch, in order to respond to the acceleration requirement of the driver as soon as possible, the control unit of the gearbox can control the Oncoming clutch to quickly rise from the third target torque to the fourth target torque and control the torque of the Offgoing clutch to quickly drop from the second target torque to the fifth target torque, so that the power response of the whole vehicle is improved.

Corresponding to the method for controlling acceleration of a vehicle during a downshift according to the embodiment of the present invention described above, referring to fig. 9, an embodiment of the present invention further provides a schematic structural diagram of an acceleration control device for a vehicle during a downshift, where the acceleration control device for a vehicle during a downshift is applied to a gearbox, and the acceleration control device for a vehicle during a downshift includes:

a first control unit 91 for controlling the clutch to rise from a first initial torque to a first target torque and controlling the torque of the Oncoming clutch to fall from a second initial torque to a second target torque when it is detected that the driver steps on the accelerator during a downshift of the vehicle; the clutch is in an engaged state at present; the first initial torque is the torque of an Offgoing clutch corresponding to a gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the Oncoming clutch is a clutch in a non-engagement state at present; the second initial torque is the torque of an Oncoming clutch corresponding to the gear of the vehicle before the downshift;

A first sending unit 92, configured to send a parabolic torque command to the Offgoing clutch when it is detected that the current torque of the Offgoing clutch is the first target torque, so that the Offgoing clutch controls the own torque to rise in a parabolic form to the torque indicated by the parabolic command based on the parabolic torque command; the torque indicated by the parabolic instruction is larger than the torque corresponding to the Lash point corresponding to the vehicle;

and a second control unit 93, configured to control, when detecting that the current torque of the off-going clutch is the torque indicated by the parabolic command, the torque line of the off-going clutch to rise until the torque line of the off-going clutch rises to the third target torque.

The specific principle and execution process of each unit in the accelerator pedal acceleration control device in the vehicle downshift according to the embodiment of the present invention are the same as those of the accelerator pedal acceleration control method in the vehicle downshift according to fig. 5 in the embodiment of the present invention, and reference may be made to the corresponding parts in the accelerator pedal acceleration control method in the vehicle downshift according to fig. 5 in the embodiment of the present invention, which will not be repeated here.

The application provides a accelerator pedal acceleration control device applied to a gearbox in a vehicle downshift process, which is used for controlling an Offgoing clutch to rise from a first initial torque to a first target torque and controlling the torque of an Oncoming clutch to drop from a second initial torque to a second target torque when detecting that a driver steps on an accelerator in the vehicle downshift process; when the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic instruction in a parabolic mode based on the parabolic torque instruction; when the current torque of the off clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque straight line of the off clutch to rise until the torque straight line of the off clutch rises to the second target torque, wherein the off clutch is the clutch in the currently engaged state; the Oncoming clutch is a clutch in a non-engagement state at present; the first initial torque is the torque of an Offgoing clutch corresponding to a gear of the vehicle before the downshift; the second initial torque is the torque of an Oncoming clutch corresponding to the gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the torque indicated by the parabolic command is greater than the torque corresponding to the Lash point corresponding to the vehicle. According to the technical scheme, in the process of vehicle downshift and acceleration, the Offgoing clutch in the engaged state is controlled to rapidly rise from the current torque (the first initial torque), and when the Offgoing clutch rises to the vicinity of the torque corresponding to the corresponding Lash point of the vehicle (the first target torque), the torque of the Offgoing clutch is controlled to rise to the torque indicated by the parabolic instruction in a parabolic manner based on the parabolic instruction, so that the smooth Lash point corresponding to the vehicle is dropped is realized, and the problem of the jerk and the frustration generated when the vehicle accelerates in the downshift process is avoided; and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, the torque of the off-going clutch is controlled to be directly increased, so that noise can be avoided in the process of downshifting and accelerating the vehicle.

Further, the vehicle downshift acceleration control device disclosed in the present application further includes:

and a third control unit for controlling the torque of the off clutch to be maintained at the first initial torque when the downshift request is received during the coasting 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.

Further, the vehicle downshift acceleration control device disclosed in the present application further includes:

a second transmitting unit for transmitting a first torque control request to an engine of the vehicle so that the engine controls the self torque to be maintained at a third initial torque based on the torque control request; wherein the third initial torque is a torque of the engine when the first torque control request is received.

Further, the vehicle downshift acceleration control device disclosed in the present application further includes:

and the third sending unit is used for sending a second torque control request to the engine so that the engine can control the self 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 control the torque of the engine to slowly rise until the rotation speed of the engine is detected to be synchronous with the rotation speed of the Oncoming clutch.

Further, the vehicle downshift acceleration control device disclosed in the present application further includes:

and a fourth control unit for controlling the Oncoming clutch to rapidly rise from the third target torque to the fourth target torque and controlling the torque of the Offgoing clutch to rapidly fall from the second target torque to the fifth target torque when the rotational speed of the engine is detected to be synchronized with the rotational speed of the Oncoming clutch.

In this specification, each embodiment is described in a progressive manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment mainly describes differences from other embodiments. In particular, for a system or system embodiment, since it is substantially similar to a method embodiment, the description is relatively simple, with reference to the description of the method embodiment being made in part. The systems and system embodiments described above are merely illustrative, wherein elements illustrated as separate elements may or may not be physically separate, and elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present invention without undue burden.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative elements and steps are described above generally in terms of functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.

Claims (10)

1. A method for controlling acceleration of a vehicle during a downshift, the method comprising:

in the process of vehicle downshifting, when the driver is detected to step on the accelerator, controlling the clutch to rise from a first initial torque to a first target torque, and controlling the torque of the Oncoming clutch to fall from a second initial torque to a second target torque; the clutch is in a currently engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the coupling clutch is a clutch in a non-engagement state at present; the second initial torque is the torque of the coupling clutch corresponding to the gear of the vehicle before the downshift;

When the current torque of the Offgoing clutch is detected to be the first target torque, a parabolic torque instruction is sent to the Offgoing clutch, so that the Offgoing clutch controls the self torque to rise to the torque indicated by the parabolic instruction in a parabolic manner based on the parabolic torque instruction; the torque indicated by the parabolic instruction is larger than the torque corresponding to the Lash point corresponding to the vehicle;

and when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction, controlling the torque of the off-going clutch to be linearly increased until the torque of the off-going clutch is linearly increased to a third target torque.

2. The method of claim 1, wherein the method further comprises, prior to the vehicle downshift:

during the coasting of the vehicle, when a downshift request is received, the torque of the off clutch is controlled to be maintained at the first initial torque to control the vehicle to slowly downshift from a current gear to a target gear indicated by the downshift request.

3. The method of claim 1, wherein the method further comprises, during the vehicle downshift, when it is detected that the driver has stepped on the throttle:

Transmitting a first torque control request to an engine of the vehicle to cause the engine to control self torque to be maintained at a third initial torque based on the torque control request; wherein the third initial torque is a torque of the engine at the time of receiving the first torque control request.

4. A method according to claim 3, wherein when it is detected that the current torque of the Offgoing clutch is the first target torque, the method further comprises:

and sending a second torque control request to the engine, so that the engine controls the self 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 rise until the rotational speed of the engine is detected to be synchronous with the rotational speed of the Oncoming clutch.

5. The method according to claim 4, wherein the method further comprises:

when it is detected that the rotational speed of the engine is synchronized with the rotational speed of the Oncoming clutch, the Oncoming clutch is controlled to quickly rise from the third target torque to a fourth target torque, and the torque of the Offgoing clutch is controlled to quickly fall from the second target torque to a fifth target torque.

6. A throttle acceleration control device for a vehicle during a downshift, said device comprising:

the first control unit is used for controlling the clutch to rise from the first initial torque to the first target torque and controlling the torque of the Oncoming clutch to drop from the second initial torque to the second target torque when the driver is detected to step on the accelerator in the process of vehicle downshift; the clutch is in a currently engaged state; the first initial torque is the torque of the Offgoing clutch corresponding to the gear of the vehicle before the downshift; the first target torque is smaller than the torque corresponding to the Lash point corresponding to the vehicle; the coupling clutch is a clutch in a non-engagement state at present; the second initial torque is the torque of the coupling clutch corresponding to the gear of the vehicle before the downshift;

the first sending unit is used for sending a parabolic torque instruction to the Offgoing clutch when the current torque of the Offgoing clutch is detected to be the first target torque, so that the Offgoing clutch can control the self torque to rise to the torque indicated by the parabolic instruction in a parabolic form based on the parabolic torque instruction; the torque indicated by the parabolic instruction is larger than the torque corresponding to the Lash point corresponding to the vehicle;

And the second control unit is used for controlling the torque straight line of the off-going clutch to rise until the torque straight line of the off-going clutch rises to a third target torque when the current torque of the off-going clutch is detected to be the torque indicated by the parabolic instruction.

7. The apparatus of claim 6, wherein the apparatus further comprises:

and the third control unit is used for controlling the torque of the off clutch to be maintained at the first initial torque when a downshift request is received in the process of vehicle coasting so as to control the vehicle to slowly downshift from the current gear to the target gear indicated by the downshift request.

8. The apparatus of claim 6, wherein the apparatus further comprises:

a second transmitting unit configured to transmit a first torque control request to an engine of the vehicle so that the engine controls the self torque to be maintained at a third initial torque based on the torque control request; wherein the third initial torque is a torque of the engine at the time of receiving the first torque control request.

9. The apparatus of claim 8, wherein the apparatus further comprises:

And the third sending unit is used for sending a second torque control request to the engine so that the sender controls the self 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 rise until the rotation speed of the engine is detected to be synchronous with the rotation speed of the coupling clutch.

10. The apparatus of claim 9, wherein the apparatus further comprises:

and a fourth control unit configured to control the Oncoming clutch to quickly rise from the third target torque to a fourth target torque and control the torque of the Offgoing clutch to quickly fall from the second target torque to a fifth target torque when it is detected that the rotational speed of the engine is synchronized with the rotational speed of the Oncoming clutch.

Images