KR100305802B1 - Method for controlling downshifting from 2 to 1-range in automatic transmission - Google Patents

Abstract

PURPOSE: A control method of downshifting from 2 to 1-range for an automatic transmission is provided to reduce shifting time by downshifting from 2 to 1-range before stopping in converting drive mode into non-drive mode or non-drive mote into drive mode, and to improve shift quality by decreasing shift shock. CONSTITUTION: A speed range during traveling is detected to be the D-range(S100), and the throttle valve opening degree is compared with the reference value in outputting a control signal for downshifting from 2 to 1-range(S120). A control unit detects vehicle speed to be within the range of downshifting from 2 to 1-range(S130), and current downshift from non-drive mode into non-drive mode(S140). Downshifting from 2 to 1-range is performed before stopping by outputting a solenoid valve driving signal from a memory to a driving unit(S150). Shift shock is reduced by decreasing shifting time.

Description

2-> 1 downshift shift control method of automatic transmission

The present invention relates to a 2 → 1 downshift shift control method of an automatic transmission. More specifically, the present invention relates to a two-speed stop in an automatic transmission in which a one-way clutch (hereinafter referred to as OW C) is not applied in a first speed shift stage. When all 2 → 1 downshift shifting control signals are output, the 2 → 1 downshift shifting control is executed only when the automatic transmission is in the non-driven, non-driven, or driven state. It relates to a 2 → 1 downshift shift control method of an automatic transmission.

In general, a vehicle equipped with an automatic transmission may be operated by automatically shifting the transmission gear to a target shift stage by controlling oil pressure within a shift range set according to the traveling speed of the vehicle and the opening amount of the throttle valve.

Therefore, a vehicle equipped with an automatic transmission in which an operating state is controlled according to hydraulic pressure as described above does not need an operation of a clutch pedal to cut off power from an engine in order to change an operating state of a corresponding shift gear. The driving fatigue can be reduced, and since the engine stall does not occur due to the driver's malfunction or immaturity during driving, the driving operation can be facilitated even for a beginner.

In the automatic transmission, a torque converter changes a rotational power of an engine, and a solenoid valve is controlled by a control signal applied from a shift control device according to a driving state of a vehicle so that a corresponding friction element is operated. A hydraulic circuit is formed to execute automatic shifting operation.

Therefore, the automatic transmission outputs a control signal corresponding to the driver's shift lever selection position, the vehicle speed, and the opening amount of the throttle valve, and the corresponding solenoid valve is driven by the output signal to change the valve port of the hydraulic circuit. And thereby control the operating state of the actuating friction element for selecting one of the gear stages of the gear stage of the transmission gear mechanism by the hydraulic pressure supplied from the oil pump.

The friction element consisting of the clutch and the brake is transferred to the drive gear after the operation state of the planetary gear device is switched according to the selective operation of the friction element, which is changed to an appropriate transmission ratio.

When the variable power is transmitted to the drive gear, the variable 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 rotational movement of the wheels to ensure stable driving. Achieve a state.

In a vehicle equipped with an automatic transmission having a new configuration operating as described above, if a 2 → 1 downshift shift control signal is output before driving, conventionally, 2 → 1 down before a stop by the shift pattern is output immediately after the shift control signal is output. Shift shift control was performed.

However, in the above-described conventional technique, when the shifting time is long when shifting and the automatic transmission shifts from driving to non-driven or non-driven when shifting, shock occurs in the engine mounting due to the shaking of the engine. There is a problem.

Accordingly, an object of the present invention is to solve the above problems, if the 2 → 1 downshift shift occurs before the vehicle is stopped while driving, the engine is in the idle state, the output shaft speed (No) of the automatic transmission is 2 → 2 → 1 downshift shift control before stop is executed only when the driving state of the automatic transmission is in the non-driven, non-driven or drive-drive mode within the range of 1 downshift. The purpose of the present invention is to provide a 2 → 1 downshift shift control method of an automatic transmission having an effect of reducing shock caused by mounting and providing a safe shifting feeling.

The present invention for achieving the above object,

A vehicle equipped with an automatic transmission that does not apply a one-way clutch, comprising: determining whether a condition for a 2 → 1 downshift shift before a stop is satisfied;

Determining whether the driving state of the vehicle maintains the non-drive state from the non-drive when the condition for the 2 → 1 downshift shifting before the stop is satisfied;

When the driving state of the vehicle maintains the non-drive state from the non-drive, characterized in that it comprises a step of outputting the 2 → 1 downshift shift control solenoid valve drive signal before stop set in the memory.

1 is a control pattern diagram for 2 → 1 downshift shift control of an automatic transmission according to an embodiment of the present invention.

2 is a 2 → 1 downshift shifting pattern diagram of an automatic transmission according to an embodiment of the present invention.

3 is a block diagram of a 2 → 1 downshift shift control apparatus of an automatic transmission according to an embodiment of the present invention;

4 is a flowchart illustrating a method of controlling a 2 → 1 downshift shifting method 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. 3, the configuration of the 2 → 1 downshift shift control apparatus of the automatic transmission according to the embodiment of the present invention is as follows.

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;

When the position of the shift lever is D range, which is the driving end, when the position of the shift lever is read and received by the signal output from the vehicle driving state sensing means 10, the engine state is idle when the 2 → 1 downshift shift control signal is output before the stop. If it is judged that the engine is in the idle state and the output shaft speed falls within the range of 2 → 1 downshift before stop, only 2 → 1 before stop when the state of the shift stage remains in the drive state from non-drive to non-drive or drive. Control means for outputting a solenoid valve driving signal for downshift shifting;

It consists of a drive means 30 to perform a shift in accordance with the solenoid valve drive signal output from the control means 20 to complete the shift without shock by the engine mounting during the shift.

In the above, the vehicle driving state detection means 10,

A throttle valve opening degree detection unit 11 for detecting an opening degree of a throttle valve whose opening and 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;

A turbine shaft rotational speed sensing unit 15 for sensing a rotational speed of the turbine shaft of the torque converter connected to the input shaft of the transmission and outputting a corresponding signal;

The shift lever detection unit 16 detects a position that is variable according to the shift lever operation of the driver and outputs a corresponding signal.

In the above configuration, with reference to the accompanying Figure 4 will be described in more detail the 2 → 1 downshift shift control method before stop in an automatic transmission that does not apply O. W. C.

In the above, the state before the stop is referred to as a state in which the engine is in an idle state while the vehicle is running, and the state in which the vehicle tries to stop while the shift stage is downshifted from the second to the first speed is referred to as a downshift before stop.

In addition, the non-driven non-driven means that the vehicle is driven and shifted by the driving speed of the vehicle, and the drive-in-drive refers to shifting the shift stage by driving the vehicle with the power of the vehicle engine. .

Therefore, the control means 20 determines whether the shift stage of the vehicle being driven is the D range which is the forward shift stage (S100).

When the shift stage is the D-range which is the forward shift stage and the under drive clutch and the 2ND brake operate as the hydraulic actuating element, the control means 20 controls the hydraulic actuating element as the underdrive clutch. It is determined whether a control signal for downshifting to the shift stage 1 speed, which is an Under Drive Clutch and a Low Reversing Brake, is output (S110).

When the control signal for downshifting the shift stage from the second speed to the first speed is output, the control means 20 determines whether the opening amount of the throttle valve is less than or equal to the set reference value (S120).

In other words, the control means 20 determines whether the engine is in an idle state.

When the value of the throttle valve in which the state of the engine is in the idle state is equal to or less than the set reference value, the control means 20 determines whether the vehicle speed of the driving vehicle is within a range capable of shifting 2 to 1 speed downshift (S130). .

In the step S130, as shown in the shift pattern diagram shown in FIG. 2, when the value of the vehicle speed No is within the range of (a), which is an area set for the throttle opening amount, the control means 20 It is determined that it belongs to the 2 → 1 downshift shifting section. The 2 → 1 downshift shiftable section is a section of (No_High <vehicle speed (No) <No_Low) in FIG.

Therefore, the control means 20 determines whether the non-drive shifting is performed in the non-drive shifting operation in which the downshift shifting currently in progress is driven by the vehicle speed of the vehicle and shifted (S140).

In the above method of determining non-driven in non-driven, the control means 20 determines non-driven in non-driven when the engine speed Ne is less than the turbine speed Nt or satisfies the arithmetic expression below. Perform.

Nt> Ne or

(No_2nd in the above is the second gear ratio,

K is a constant for calculation,

로 출력축 회전수의 변화율이고,| dNo / dt |

Is the rate of change of the output shaft rotational speed,

T_ss-sb is for the actual duty output

Is the value up to

GR_first is the first gear ratio,

Ne_Current is the value of the current engine speed Ne.

로 엔진 회전수의 변화량N_margin1 is

Change in engine speed

to be.)

When the downshift shift is the non-drive shift in the non-drive where the vehicle is driven and shifted by the vehicle speed of the vehicle, the control means 20 outputs the solenoid valve driving signal stored in the memory to the drive means 30 before stopping. 2 → 1 downshift shifting is performed (S150).

However, when the down shift shift is not a shift from non-driven to non-driven when the vehicle is driven and shifted by the vehicle speed of the vehicle, the control means 20 determines that the downshift shift is driven by the engine driving of the vehicle. It is determined whether the shift from the shifting drive to the drive is made (S141).

Accordingly, in the above method, the driving state of the vehicle is determined to be driving from driving. When the engine speed Ne is greater than the engine speed Nt of the turbine or satisfies the arithmetic expression below, the control means 20 drives in driving. Perform the judgment.

Nt <Ne or

(No_2nd in the above is the second gear ratio,

K is a constant for calculation,

로 출력축 회전수의 변화율이고,| dNo / dt |

Is the rate of change of the output shaft rotational speed,

T_ss-sb is for the actual duty output

Is the value up to

GR_first is the first gear ratio,

Ne_Current is the current engine speed Ne

로 엔진 회전수의 변화량N_margin2 is

Change in engine speed

to be.)

In the case where the downshift shift is shifted from driving to shifting by driving the vehicle by driving the engine of the vehicle, the control means 20 transfers the solenoid valve driving signal stored in the memory to the driving means 30. The output is then shifted 2 → 1 downshift before stopping (S150).

However, if the downshift shift is not a shift from non-drive to non-drive or drive to drive or does not satisfy the 2 → 1 downshift shift condition before stop, the control means 20 returns to the main routine to Perform control.

However, in the above case, when the non-drive determination in the non-drive and the drive determination in the drive are simultaneously performed at the time of 2 → 1 downshift before stop, the control means 20 gives priority to the non-drive determination in the non-drive.

In addition, if it is determined in step S100, step 110, step S120, and step S130 that the corresponding determination conditions are not satisfied, the control means 20 returns to the main routine to perform normal control.

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, 2 → 1 down before stop when the pre-stop condition is satisfied regardless of the driving condition of the vehicle, and the operation state of the vehicle is shifted from non-drive to non-driven or from drive to drive when shifting. By performing shift shifting, a 2 → 1 downshift shift control method of an automatic transmission having an effect of providing a stable shifting feeling during shifting may be provided by shortening the shifting time to reduce shock generated in engine mounting.

Claims (6)

A vehicle equipped with an automatic transmission that does not apply a one-way clutch, comprising: determining whether a condition for a 2 → 1 downshift shift before a stop is satisfied; Determining whether the driving state of the vehicle maintains the non-drive state from non-drive when the condition for 2 → 1 downshift shifting before stopping is satisfied; And outputting a 2 → 1 downshift shift control solenoid valve driving signal before stop set in the memory when the driving state of the vehicle is maintained in the non-driven state. → 1 Downshift shift control method. The method of claim 1, further comprising: determining whether the driving state of the vehicle is the driving state when the driving state of the vehicle is not the non-driven state when the vehicle is not driven; When the driving state of the vehicle maintains the driving state in the drive, the 2 → 1 of the automatic transmission, characterized in that it comprises the step of outputting the 2 → 1 downshift shift control solenoid valve drive signal set before the stop in the memory. How to control downshift shifting. The method of claim 1, further comprising: determining whether the shift lever is in the D range; When the shift lever is in the D range, determining whether a 2 → 1 downshift shifting signal is output before stopping; Determining whether the engine is in an idle state when the 2 → 1 downshift shift control signal is output before stopping; Determining whether a vehicle speed (No) is included in a 2 → 1 downshift shifting section before stopping when the engine is in an idle state; When the vehicle speed (No) is included in the 2 → 1 downshift shifting section before stopping, the 2 → 1 downshift shifting control of the automatic transmission that determines that the condition for performing the 2 → 1 downshift shifting before stopping is satisfied. Way. The method according to claim 1, wherein the 2 → 1 downshift shifting control method of the automatic transmission comprising performing a normal shift control when the 2 → 1 downshift shifting condition before stopping is not satisfied. The method of claim 1, wherein the method of determining whether the driving state of the vehicle is non-driven is non-driven when the engine speed Ne is less than the engine speed Nt of the turbine or satisfies the following arithmetic expression. 2 to 1 downshift shift control method of the automatic transmission comprising the step of determining that. {

(No_2nd in the above is the second gear ratio, K is a constant for calculation, | dNo / dt | is the rate of change of the number of revolutions of the output shaft, T_ss-sb is for the actual duty output Is the value up to GR_first is the first gear ratio, Ne_Current is the current engine speed Ne N_margin1 is

Change in engine speed to be.) The method of claim 1, wherein the method of determining whether the driving state of the vehicle is driving is driving, and determining whether the driving speed is driving when the engine speed Ne is greater than the engine speed Nt of the turbine or satisfies the following arithmetic expression. 2 → 1 downshift shift control method of the automatic transmission comprising a. {

(No_2nd in the above is the second gear ratio, K is a constant for calculation, | dNo / dt |

Is the rate of change of the output shaft rotational speed, T_ss-sb is for the actual duty output Is the value up to GR_first is the first gear ratio, Ne_Current is the current engine speed Ne N_margin2 is

Change in engine speed to be.) }

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