KR100262603B1 - Synchronizing control method at power-on down shift - Google Patents

Abstract

PURPOSE: A control method for a synchronism state of a power-on down shift is provided to enhance riding comfort and shift feel by minimizing shift shock during the power-on down shift of an automatic transmission. CONSTITUTION: A control system for a synchronism state of a power-on down shift in an automatic transmission comprises a traveling state sensor(10) outputting an electric signal according to the traveling state of a vehicle; a control device(20) controlling an A and a B section by a feedback with the electric signal, starting to control a C section when a turbine rpm(revolutions per minute) is more that or the same as the X4, outputting an error value by operating the turbine rpm with the final hydraulic control signal of the B section as an initial integral value and synchronous velocity, stopping controlling the C section when the turbine rpm reached at the synchronous velocity, reducing an apply member duty at a regular steepness once a D section is controlled, and controlling the speed of the turbine rpm with the synchronous velocity and the error value by controlling the turbine rpm by a feedback; and a drive device(30) synchronizing a gear lever with a duty control signal from the control device. The traveling state sensor contains a throttle valve opening degree detecting sensor(11), a velocity sensor(12), a gearshift lever sensor(13), an engine rpm sensor(14) and a turbine rpm sensor(15).

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 synchronism during power-on downshift of an automatic transmission of an application member feedback method for appropriately replacing 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. The hydraulic pressure acts on the valve to allow the shifting operation to be performed.

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 of the gear stages 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 movement of the friction element, which consists 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 which is geared with the longitudinal reduction gear by the driven gear which is geared with the drive gear, thereby controlling the rotation 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 the automatic transmission operating as described above, if the shift occurs due to the speed and the throttle opening degree, the shift stage is duty controlled by the set duty control signal and the shift is synchronized to the target shift stage. After the synchronous determination was made before the RPM value of the turbine was set just before the shift stage was synchronized with the target shift stage, the shift stage was gradually synchronized with the target shift stage.

However, the above-described conventional technology does not calculate the exact value of the duty control signal according to the change of the vehicle, so that the shift member does not replace the release member and the application member so that a 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. When the section D control is started, the application member duty Da is reduced to a constant slope, and the turbine RPM Nt is fed back. By controlling the release member torque (Tr) by controlling the speed of the RPM (Nt) of the turbine in accordance with the synchronous speed and the error by the control, the change occurs at the moment of synchronization during power-on downshift shifting of the automatic transmission To minimize the shock and improve the ride comfort, it is possible to provide a power-on shift-down when near synchronous control method for an automatic transmission that has an effect to improve the byeonsokgam.

The present invention for achieving the above object,

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, the control of the section C is terminated, the section D starts, and the application member duty decreases to a certain slope, and the release member duty Dr is reduced to 100% from the beginning. Outputting;

Determining whether the interval D satisfies the termination condition according to the output of the release member duty Dr at 100%;

Determining whether the torque value Tr of the release member or the hydraulic pressure Pr of the release member is 0 when the end condition of the section D is satisfied;

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 and down shift of an automatic transmission according to an exemplary embodiment of the present invention.

3A, 3B, and C are flowcharts of a method of controlling near synchronization during power-on down shift of the automatic transmission according to the 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 of a configuration of a near-synchronous controller during power on and down shift of an automatic transmission according to an embodiment of the present invention is shown.

A vehicle driving state sensing means 10 which receives a signal that is varied in the state of the vehicle and outputs a corresponding electric signal according to a driving state of the vehicle;

After receiving the signal output from the vehicle driving state sensing means 10 and performing section A and section B by feedback control, and ending section B when the turbine RPM is greater than or equal to the set value X4. Start 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 by the calculated error value When the RPM value reaches the synchronous speed, the control of the above section C ends, and when the section D control starts, the application member duty Da is reduced to a constant slope, and the turbine RPM (Nt) of the turbine is fed back to control the synchronization. Control means 20 for controlling the release member torque Tr by controlling the speed of the RPM Nt of the turbine in accordance with the speed and the error;

It consists of a driving 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 operation state detection means 10,

A throttle valve opening detection unit 11 for detecting an opening degree of a throttle valve whose opening / closing state is variable in association with an operation state of the accelerator pedal and outputting a corresponding signal;

A vehicle speed detector 12 which detects a driving speed of the vehicle and outputs a corresponding signal;

A shift stage detecting unit 13 for detecting a variable state of the shift stage and outputting 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 sensing 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 value of the RPM (Nt) of the turbine (X4) (S110).

Nt≥X4

Where Nt is the RPM of the current turbine,

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

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 ends 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 starts, the control means 20 determines whether the section C Start flag is set to 1 (S131).

When the Start flag of the section C is set to 1, 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 O and reads the RPM value of the current turbine (S133, 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-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.)

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 included in the synchronous speed range 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.)

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 section D starts, the control means 20 releases the release member in the section 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 control subroutine for the section D of FIG. 1 as follows.

When the interval D is started, the duty value of the new appli- tion member Da is calculated in order to calculate the current appli- cation member Da by the set reference value and to decrease it by a predetermined slope (S151).

As the duty value of the new applicator Da is calculated in order to calculate the current applicator Da by the set reference value and reduce it to a constant slope, the control means 20 controls the RPM Nt of the turbine. By controlling the feedback, the release member torque (Tr) is controlled according to the synchronization speed and the error value (S152).

Therefore, the control means 20 outputs the application member duty value Da0 calculated above to the drive means 20, and controls the application member torque Ta while increasing the application member hydraulic pressure Pa constantly ( S153).

As the application member duty Da is output in the above, the control means 20 determines whether the end condition of the section D is satisfied (S154).

When the end condition of the section D is satisfied above, the control means 20 ends the control of the section D.

However, when the end condition of the section D is not satisfied, the control means 20 calculates the duty of the new appli- ble member Da in order to reduce the current appli- cation member Da by a predetermined reference value and to reduce it to a constant slope. It returns to step S154 of calculating the value.

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 performs the above section D control by 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 integral initial value, 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, and the RPM value of the turbine reaches the synchronous speed. When the control of the section C is terminated and the section D control is started, the application member duty Da is reduced to a constant slope, and the turbine RPM (Nt) is fed back to control the turbine RPM according to the synchronous speed and error. By controlling the release member torque (Tr) by controlling the speed of (Nt), it is possible to minimize the shift shock generated at the synchronous moment during power-on downshift shifting of the automatic transmission to improve ride comfort, Can provide a power-on down-shift control method upon synchronization near the automatic transmission has the effect that can enhance a sense.

Claims (6)

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 so that the RPM (Nt) of the turbine is approached to the maximum synchronous speed by feedback control. Wow; 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, the control of the section C is ended, and when the section D starts, the new application member Da is calculated by using the set reference value to reduce the constant slope. Calculating a duty value of the fly member Da; At this time, the control means for controlling the release member torque (Tr) according to the synchronization speed and the error value (Error) by feedback control the RPM (Nt) of the turbine; Outputting the calculated application member duty value Da to control the application member torque Ta while constantly increasing the application member hydraulic pressure Pa; Determining whether an end condition of the interval D is satisfied by outputting the application member duty Da; Terminating control of the interval D when the termination condition of the interval D is satisfied; Determining whether the torque value Tr of the release member or the oil pressure Pr of the release member is zero, when the control of the section D is terminated; 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 RPM of the current turbine and X4 is the RPM of the turbine set at the final sync point in section B. (Sync speed-Ns) ≤Nt≤ (sync speed + Ns) (Nt is the RPM value of the current turbine, sync speed-Ns is the range before sync speed, sync speed + Ns is the range after sync speed, and Ns is any set constant) Da = Da-Δa (Where Da is the new application member duty value and ΔDa is the set reference value) The interval D end condition above (Where Ta is the application member torque, KA is the arithmetic constant, and Tt is the torque of the torque converter)} The method of claim 1, further comprising returning to the operation step for continuously decreasing the duty of the applicator member by a predetermined slope when the end condition of the interval D is not satisfied. 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 method of claim 1, wherein if the RPM value of the turbine is not included in the synchronous speed range, power on down of the automatic transmission comprising 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-Nt (In this case, the error value is a difference value calculated by the synchronous speed and the RPM value of the turbine, and the synchronous speed is the RPM value of the turbine at the target shift stage, i.e., output shaft rotation speed (No) × gear ratio.) Nt is the RPM of the current turbine.) Compensation Duty = f (Error) (Where f is a calculation function and Error is the difference calculated by the synchronous speed and the RPM of the turbine.)