KR19980060224A - Synchronous control method during power-on downshift of automatic transmission - Google Patents

Abstract

The present invention relates to a control method near the synchronous during power-on downshift of an automatic transmission, wherein the shift stage is changed by the vehicle speed and the opening amount of the throttle valve, and the A and B sections are used for the feedback control. Performing control to bring the turbine's RPM (Nt) as close to the synchronous speed as possible; Determining whether the RPM (Nt) of the turbine is greater than X4, the set RPM (Nt) value of the turbine in the section B; In the above section, if the RPM (Nt) of the turbine is greater than or equal to X4, the RPM (Nt) value of the set target turbine, the control of the section B is terminated, the section C Start flag is set to 1, and the section C control is performed. Calculating a compensation duty of performing a subroutine to perform; Determining whether the RPM (Nt) value of the turbine is within a synchronous speed range as the compensation duty is output by performing the control of the interval C; When the RPM value of the turbine is within the synchronous speed range, terminating the control of the section C, performing a section D subroutine, and outputting a release member duty value Dr and an application member Da; Determining whether the torque value Tr of the release member or the hydraulic pressure Pr of the release member is 0 according to the output of the release member duty value Dr and the application member duty value Da; When the torque value (Tr) of the release member or the hydraulic pressure (Pr) of the release member is 0, the step is to end all the shift control and to return to the initial stage, at the moment of synchronization at the time of shifting the power-on down shift of the automatic transmission By minimizing the shift shock generated, there is an effect that can improve the ride comfort, improve the shift feeling.

Description

Control method near synchronous during power-on downshift of automatic transmission

The present invention relates to a method of controlling near synchronism during power-on downshift of an automatic transmission, and more particularly, to minimize shift shock that occurs at the moment of synchronism during power-on downshift shifting in a vehicle equipped with an automatic transmission. The present invention relates to a method of controlling near synchronization during power-on and down shift of an automatic transmission of an open loop type to appropriately replace a release member and an apply member.

In general, a vehicle equipped with an automatic transmission controls the hydraulic pressure within a shift range set according to the driving speed of the vehicle so that the shift gear of the target shift stage may be automatically operated.

Therefore, the torque converter is operated according to the output power of the engine to control the rotational force of the fluid, and according to the control signal applied from the shift control device so that the shift gear according to the operating state of the vehicle can be operated. Hydraulic pressure acts on the valve to allow shifting.

Therefore, a vehicle equipped with an automatic transmission in which the operating state is controlled according to the hydraulic pressure does not require the operation of a clutch pedal to cut off power from the engine in order to change the operating state of the corresponding shift gear. Fatigue can be reduced, and an engine stall does not occur due to malfunction or inexperience of a driver while driving, so that even a beginner can easily operate a driving operation.

Therefore, the automatic transmission receives a fluid pressure from the oil pump by changing the port according to the selected position of the driver's shift lever, and the operating state of the hydraulic valve is changed by the fluid pressure so that any one gear stage of the transmission gear mechanism is shifted. Controls the operating state of the hydraulically actuated friction element for selecting stages.

The action of the planetary gear arrangement is switched in accordance with the selective operation of the friction element consisting of a clutch or brake, which is then transmitted to the drive gear after an appropriate transmission ratio is made.

When the shifted power is transmitted to the drive gear, the shifted power is transmitted to the driven gear geared to the longitudinal reduction gear by the driven gear geared to the drive gear, thereby controlling the rotational movement of the wheel.

As described above, the target shift stage is determined according to the driving state of the vehicle, and when the control operation to the determined target shift stage is executed, the corresponding friction element is operated for each target shift stage among friction elements consisting of a clutch or a brake. Let's do it.

In a vehicle equipped with an automatic transmission operating as described above, if a shift occurs due to the speed and the throttle opening, the shift stage is duty controlled by the set duty control signal and shifted to the target shift stage, and thus, the conventional duty control signal is set. After the synchronous determination was made before the RPM value of the turbine was set just before the shift stage was synchronized to the target shift stage, the shift stage was gradually synchronized to the target shift stage.

However, the conventional technique described above does not calculate the exact value of the duty control signal according to the change of the vehicle, so that the release member and the application member cannot be replaced properly, and shift shock occurs at the moment of power-on down shift synchronization. There is a problem.

Therefore, in order to solve the above-mentioned conventional problem, as shown in the accompanying FIG. 1, section A and section B are performed by the feedback control, and section B is set when the RPM of the turbine is greater than or equal to the set value X4. After the end, start section C control, calculate the error value by calculating the RPM of the turbine with reference to the synchronous speed using the last hydraulic control signal of the section B as the integral initial value, and calculate the compensation duty based on the error value calculated above. When the RPM value of the turbine reaches the synchronous speed, the control of the section C is terminated, the section D control is started, and the release member is released from the point a. When the torque Tr value of the release member becomes 0, all the controls By closing the shift, the shift shock that occurs at the moment of synchronism during power-on-down shifting of the automatic transmission can be minimized to improve the riding comfort and improve the shifting feeling. It is to provide a method of controlling near synchronous during power-on down shift of a true automatic transmission.

According to the present invention for achieving the above object, when the speed change stage is changed by the vehicle speed and the opening amount of the throttle valve, section A and section B are the RPM (Nt) of the turbine by the feed back control Performing control to approach the synchronous speed as much as possible; Determining whether the RPM (Nt) of the turbine is greater than X4, the set RPM (Nt) value of the turbine in the section B; In the above section, if the RPM (Nt) of the turbine is greater than or equal to X4, the RPM (Nt) value of the set target turbine, the control of the section B is terminated, the section C Start flag is set to 1, and the section C control is performed. Calculating a compensation duty of performing a subroutine to perform; Determining whether the RPM (Nt) value of the turbine falls within a synchronous speed range as the compensation duty is output by performing the control of the interval C; When the RPM value of the turbine is within the synchronous speed range, terminating the control of the section C, performing a section D subroutine, and outputting a release member duty value Dr and an application member Da; Determining whether the torque value Tr of the release member or the hydraulic pressure Pr of the release member is 0 according to the output of the release member duty value Dr and the application member duty value Da; When the torque value (Tr) of the release member or the hydraulic pressure (Pr) of the release member is 0, it is characterized in that it comprises the step of ending all the shift control and return to the initial stage.

1 is a duty pattern diagram for near-synchronous control during power-on down shift of an automatic transmission according to an embodiment of the present invention.

2 is a block diagram illustrating a configuration of a near-synchronous controller during power-on down shift of an automatic transmission according to an exemplary embodiment of the present invention.

3A, 3B, and 3C are flowcharts illustrating a method for controlling a power-on-down shift near synchronization of an automatic transmission according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention, which can be achieved and realized in detail by the above objects, will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, a block diagram showing a configuration of a near-synchronous control device during power-on downshifting of an automatic transmission according to an exemplary embodiment of the present invention is provided to output a signal in which the state of the vehicle is changed according to the driving state of the vehicle. A vehicle driving state sensing means 10 which receives an authorization and outputs a corresponding electric signal; The section C control is started by ending section B when the RPM (Nt) of the turbine is greater than or equal to the set value X4 by reading the signal output from the vehicle driving state sensing means 10 and ending the section B. Using the hydraulic control signal as the integral initial value, the RPM (Nt) of the turbine is calculated with reference to the synchronous speed, and an error value is calculated. The compensation duty is calculated and output from the calculated error value, and the RPM (Nt) of the turbine is calculated. When the value reaches the synchronous speed, the control of the above section C is terminated, the section D control is started, the release member is released from the point a, and when the torque Tr value of the release member reaches 0, the shift control to end all the controls. Means (20); It consists of a drive means 30 for synchronizing the shift stage by receiving a duty control signal output from the shift control means 20.

In the above, the vehicle operating state detection means 10, the throttle valve opening degree detection unit 11 for detecting the opening degree of the throttle valve whose opening and closing state is variable in conjunction with the operation state of the accelerator pedal and outputs a corresponding signal; A vehicle speed detector 12 which detects a driving speed of the vehicle and outputs a corresponding signal; A shift stage sensing unit 13 configured to detect a variable state of the shift stage and output a corresponding signal when the shift stage is changed according to the throttle valve opening amount and the vehicle speed; An engine rotation speed detection unit 14 for detecting a rotation speed of the crankshaft which is varied according to an operating state of the engine and outputting a corresponding signal; Turbine shaft rotation speed detection unit 15 for detecting the rotational speed of the turbine shaft of the torque converter connected to the input shaft of the transmission and outputs a corresponding signal.

When the vehicle starts to travel and the shift stage is changed by the opening speed of the vehicle speed and the throttle valve, the control section 20 performs section A and B shown in FIG. The control is performed so that the RPM (Nt) of the synchronous speed as close as possible (S100).

Therefore, it is determined whether the RPM (Nt) of the turbine in the section B is greater than the set RPM (Nt) value X4 of the turbine (S110).

Nt ≥ X4

Where Nt is the RPM of the current turbine,

X4 is the RPM value of the turbine set at the last sync point in section B

to be.)

When the RPM (Nt) of the turbine in the section B is greater than or equal to X4, which is the RPM (Nt) value of the set target turbine, the control means 20 terminates the control of the section b, and sets the section C Start flag to 1. Then, a subroutine for performing section C control is performed (S120 and S130).

However, when the RPM (Nt) value of the turbine does not reach the RPM value X4 of the set target turbine in the section B, the control means 20 until the RPM value of the turbine reaches the RPM value of the target turbine. Continue to control.

When the control of the section C is started, the control means 20 determines whether the Start flag of the section C is set to 1 (S131).

When the Start flag of the section C is set to 1 in the above, the control means 20 calculates the integral initial value of the section C by setting the final hydraulic control signal of the section B as the integration initial value (S132).

When the integral initial value of the section C is calculated in the above, the control means 20 sets the section C Start flag to 0 and reads the RPM value of the current turbine (S133, S134).

However, when the section C Start flag is not 1, the control means 20 inputs and reads the RPM (Nt) of the current turbine in order to input and read the RPM (Nt) of the current turbine in the C section. (S134).

As the RPM value of the turbine is read in the above, the control means 20 calculates an appropriate error value by calculating the RPM value of the current turbine at the synchronous speed by a set equation (S135).

Error = Sync Speed-Nt

(In this case, the Error value is the difference value calculated by the synchronous speed and the RPM value of the turbine.

The synchronous speed is RPM of the turbine at the target speed,

(That is, output shaft rotation speed (No) x gear ratio)

Nt is the RPM of the current turbine.

to be.)

As the error value is calculated in the above, the control means 20 calculates the compensation duty value by calculating the error value by the function f (S136).

Compensation Duty = f (Error)

As the compensation duty value is calculated, the control means 20 sets the initial duty value, the duty gradient, the duty output time, etc. stored in the memory according to the calculated duty value, and drives the corresponding duty control signal. Output to 30 and return to the main routine (S137).

As the control duty of the section C is output and the compensation duty is output, it is determined whether the RPM (Nt) value of the turbine is within the range of the synchronous speed due to difficulty in performing accurate synchronous determination of the control means 20 (S140). .

(Sync speed-Ns) ≤ Nt ≤ (sync speed + Ns)

Where Nt is the RPM of the current turbine,

Sync speed-Ns is the range before sync speed,

Sync speed + Ns is the range after sync speed,

Ns is an arbitrary setting constant

to be.)

When the RPM value of the turbine is within the synchronous speed range, the control means 20 terminates the control of the section C and performs a subroutine for performing the section D (S150).

However, if the RPM value of the turbine is not included in the synchronous speed range in the above, the control means 20 continues to perform the interval C subroutine so that the RPM of the turbine reaches the maximum synchronous speed.

Therefore, up to the above section C, the release member (Release Member) to control the feedback to accelerate the RPM (Nt) of the turbine to the synchronous speed.

As shown in FIG. 1 attached above, when the subroutine of the interval D is started, the control means 20 releases the release member in the interval D and catches the application member. The torque a of the release member maintains the speed relationship of the low gear, and at the end of the D section, the torque b of the application member maintains the speed and torque of the low gear. End the shift.

Therefore, the control means 20 performs the subroutine of the interval D as follows.

The duty Dr of the release member is calculated by calculating an arbitrary value? Dr from the current release member duty value Dr by a set arithmetic expression (S151).

Dr = Dr-△ Dr

Where Dr is the duty of the release member,

ΔDr is any arithmetic constant.)

In addition, the torque Tr of the release member releases a value calculated by differentiating the hydraulic pressure Pr of the release member and the torque Tr of the release member with respect to the change of the hydraulic pressure Pr of the release member. The torque Tr of the release member is calculated by calculating the member hydraulic pressure Pr and the torque dead zone of the release member by a value calculated by the set arithmetic expression (S152).

(Where Tr is the torque value of the release member,

Pr is the hydraulic pressure of the release member,

Is the change amount of the release member torque (Tr) with respect to the change in the hydraulic pressure (Pr) of the release member,

Dead Zone (r) is the torque dead zone of the release member

to be.)

Therefore, the hydraulic pressure Pr of the release member may be calculated as a function of the duty value of the release member.

Pr = f (Dr)

Where f is an arithmetic function

The control means 20 which calculated the duty value Dr of the release member and the torque value Tr of the release member as described above reads the RPM value Ne of the current engine and the RPM Nt of the turbine (S153). .

The RPM (Ne) value of the engine and the RPM (Nt) of the turbine read out above are calculated by the set function (f) arithmetic equation to calculate the torque ratio (a) of the torque converter (C) and the torque converter (a). The torque value Tt of the torque converter is calculated by calculating the C-Factor (C) of the torque converter, the torque ratio (a) of the torque converter, and the value of the engine speed Ne ² by the set arithmetic equation. To calculate (S154).

Tt = λ · C · Ne ²

Where Tt is the torque value of the torque converter,

λ is the torque ratio of the torque converter,

C is the C-Facter of the torque converter,

Ne ² is the RPM of the engine

to be.)

Accordingly, the torque Tr of the release member at the point a of the duty pattern diagram for near-synchronous control during power-on downshift of the automatic transmission according to FIG. 1 can be calculated as follows.

The torque Ta of the application member at point b can be calculated as follows.

Accordingly, the relationship between the torque Tr of the release member and the application member Ta during the interval D may be represented as follows, and the application member Ta may be calculated (S155).

Where Ta is the talk of the application member at b,

Tt is the torque of the torque converter,

Tr is the torque of the release member,

Ka and Kr are constants of operation

to be.)

That is, at the point a shown in FIG. 1, the torque Tr of the release member is maintained in the C section, and after that, the torque Tr of the release member is reduced by a constant slope, and the above Equation (1) According to the step of controlling the torque (Ta) of the application member.

Therefore, the control means 20 can calculate the duty Da of the application member as follows (S156).

Da = f (Pa)

Where Da is the duty of the application member,

f is a math function,

Pa is the hydraulic pressure of the application member

to be.)

Therefore, Pa can be calculated as follows.

Where Pa is the hydraulic pressure of the application member,

Ta is the talk of the application member,

Is the change amount of Pa with respect to the change of the hydraulic pressure Ta of an application member,

DeadZone (a) is an application member's talk DeadZone

to be.)

As the control means 20 calculates the duty Dr of the release member and the duty Da of the application member, the control means 20 sets the initial duty value, the duty slope, the duty output time, etc. in the memory map to drive the corresponding control signal. The control unit 30 outputs to the means 30 to control the section D and returns to the main routine (S157).

As the subroutine of the section D is completed, the control means 20 determines whether the torque value Tr of the release member or the hydraulic pressure Pr of the release member is 0 (S160).

When the torque value Tr of the release member or the hydraulic pressure Pr of the release member is 0, the control means 20 ends all shift control and returns to the initial stage (S170).

However, when the torque value Tr of the release member or the hydraulic pressure Pr of the release member is not 0, the control means 20 controls the above section D control to the torque value Tr of the release member or the hydraulic pressure of the release member. It continues until (Pr) becomes 0.

The above embodiments are described as the most preferred embodiments, and the present invention is not limited thereto, and the embodiments can be easily described from the above embodiments.

As described above, in the embodiment of the present invention, section A and section B are performed by the feedback control, and section B control is started by ending section B when the turbine RPM is greater than or equal to the set value X4, and the section B Using the last hydraulic control signal of the section as the initial value of integration, the RPM value of the turbine is calculated by referring to the synchronous speed, and the compensation duty is calculated based on the error value calculated above. Ending the control of the above section C, starting the section D control, releasing the release member from point a, and ending all the control when the torque Tr value of the release member becomes 0, thereby turning on the power on down of the automatic transmission. Synchronization during power-up and downshifting of automatic transmissions with the effect of minimizing shift shocks at the moment of shifting to improve riding comfort and improving shifting feeling. It can provide processing control method.

Claims (7)

If the shift stage is changed by the vehicle speed and the opening amount of the throttle valve, the sections A and B are controlled to bring the turbine RPM (Nt) to the maximum synchronous speed by the feedback control. Steps; Determining whether the RPM (Nt) of the turbine is greater than X4, the set RPM (Nt) value of the turbine in the section B; In the above section, if the RPM (Nt) of the turbine is greater than or equal to X4, the RPM (Nt) value of the set target turbine, the control of the section B is terminated, the section C Start flag is set to 1, and the section C control is performed. Calculating a compensation duty of performing a subroutine to perform; Determining whether the RPM (Nt) value of the turbine is within a synchronous speed range as the compensation duty is output by performing the control of the interval C; When the RPM value of the turbine is within the synchronous speed range, terminating the control of the section C, performing a section D subroutine, and outputting a release member duty value Dr and an application member Da; Determining whether the torque value Tr of the release member or the hydraulic pressure Pr of the release member is 0 according to the output of the release member duty value Dr and the application member duty value Da; When the torque value (Tr) of the release member or the hydraulic pressure (Pr) of the release member is 0, when the power-on shift of the automatic transmission, comprising the step of ending all the shift control and return to the initial stage Control method near synchronous. {Nt ≥ X4 Where Nt is the current turbine RPM X4 is the RPM value of the turbine set at the last sync point in section B to be.) (Sync speed-Ns) ≤ Nt ≤ (sync speed + Ns) Where Nt is the RPM of the current turbine, Sync speed-Ns is the range before sync speed, Sync speed + Ns is the range after sync speed, Ns is an arbitrary setting constant to be.)} The method of claim 1, wherein when the torque value Tr of the release member or the hydraulic pressure Pr of the release member is not 0, the above section D control is performed by the torque value Tr of the release member or the hydraulic pressure Pr of the release member. A method of controlling near synchronism upon power-on downshift of an automatic transmission, the method comprising continuing to perform until zero. The power on down of the automatic transmission according to claim 1, wherein if the RPM value of the turbine is not included in the synchronous speed range, continuing to perform the section C subroutine so that the RPM of the turbine reaches the maximum synchronous speed. Control method near synchronous at shift. The method according to claim 1, wherein when the RPM (Nt) value of the turbine does not reach the RPM value X4 of the set target turbine in the section B, the control means 20 until the RPM value of the turbine reaches the RPM value of the target turbine. A method of controlling near synchronism upon power-on downshift of an automatic transmission, the method comprising continuing to perform a control of a section B. The method of claim 1, further comprising: determining whether the start flag of the interval C is set to 1; Calculating an integral initial value of the interval C using the final hydraulic control signal of the interval B as an integral initial value when the Start flag of the interval C is set to 1; Setting the interval C Start flag to 0 when the integral initial value of the interval C is calculated, and reading the RPM value of the current turbine; Calculating an appropriate error value by calculating the RPM value of the current turbine at a synchronous speed by a set equation according to the RPM value of the turbine; Calculating a compensation duty value by calculating the error value by a function f as the error value is calculated; According to the calculation of the duty duty value, the initial duty value, duty slope, duty output time, etc. stored in the memory are set according to the calculated duty value, and the corresponding duty control signal is output and returned to the main routine. A method of controlling near synchronism during power-on downshift of an automatic transmission, including. {Error = Sync Speed-Nt (In this case, the Error value is the difference value calculated by the synchronous speed and the RPM value of the turbine. Synchronous speed is the RPM value of the turbine of the target shift stage, (That is, output shaft rotation speed (No) x gear ratio) Nt is the RPM of the current turbine. to be.) Compensation Duty = f (Error) (Where f is an arithmetic function, Error is difference value calculated by synchronous speed and turbine RPM to be.) The method of claim 5, wherein if the section C Start flag is not 1, the step of inputting and reading the RPM (Nt) of the current turbine to read and input the RPM (Nt) of the current turbine in section C is performed (S134). A method of controlling near synchronism upon power-on downshift of an automatic transmission, comprising: a. The method of claim 1, wherein the subroutine performing method of the interval D calculates a duty Dr of a member of the release member by calculating an arbitrary value ΔDr from a current release member duty value Dr by a set arithmetic expression. Making a step; The value calculated by differentiating the torque Tr of the release member from the torque Tr of the release member with respect to the change of the hydraulic pressure Pr of the release member and the torque Pr of the release member and the torque Tr of the release member is obtained. Calculating the torque Tr of the release member by calculating the oil pressure Pr and the torque dead zone of the release member by a value calculated by the set arithmetic formula; Reading the RPM of the current engine Ne and the RPM of the turbine Nt; The RPM (Ne) value of the engine and the RPM (Nt) of the turbine read out above are calculated by the set function (f) arithmetic equation to calculate the torque ratio (λ) of the C-Factor (C) of the torque converter and the torque converter. The torque value Tt of the torque converter is calculated by calculating the C-Factor (C) of the torque converter, the torque ratio λ of the torque converter, and the value of the engine speed Ne ² by the set arithmetic equation. Calculating a; Calculating an application member Ta according to the relationship between the torque Tr of the release member and the application member Ta during the interval D; Calculating a duty Da of the application member; As the duty Dr of the release member and the duty Da of the application member are calculated, the initial duty value, the duty gradient, the duty output time, etc. are set in the memory map, and the corresponding control signal is output to control the interval D. A method of near-synchronous control during power-on downshift of an automatic transmission, including returning to the main routine. {Dr = Dr-△ Dr Where Dr is the duty of the release member, ΔDr is any arithmetic constant.) (Where Tr is the torque value of the release member, Pr is the hydraulic pressure of the release member, Is the change amount of the release member torque (Tr) with respect to the change in the hydraulic pressure (Pr) of the release member, Dead Zone (r) is the torque dead zone of the release member to be.) Therefore, the hydraulic pressure Pr of the release member may be calculated as a function of the duty value of the release member. Pr = f (Dr) (Where f is an arithmetic function) Where Tt is the torque value of the torque converter, λ is the torque ratio of the torque converter, C is the C-Facter of the torque converter, Ne ² is the RPM of the engine to be.) The torque Tr of the release member at point a of the duty pattern diagram for near-synchronous control at the time of power-on downshift of the automatic transmission can be calculated as follows. The torque Ta of the application member at point b can be calculated as follows. Where Ta is the talk of the application member at b, Tr is the torque of the torque converter, Tr is the torque of the release member, Ka and Kr are constants of operation to be.) Da = f (Pa) Where Da is the duty of the application member, f is a math function, Pa is the hydraulic pressure of the application member to be.) Therefore, Pa can be calculated as follows. Where Pa is the hydraulic pressure of the application member, Ta is the talk of the application member, Is the change amount of Pa with respect to the change of the hydraulic pressure Ta of an application member, DeadZone (a) is an application member's talk DeadZone to be.)