JP2009047032A - Control device for vehicle shift - Google Patents

Abstract

[PROBLEMS] To cope with a double clutch operation of a driver in rotation synchronous control at the time of shifting in an MT vehicle.
SOLUTION: When a clutch release is detected by a clutch pedal switch, a target engine rotational speed necessary for traveling at a target gear position after shifting by a shift operation of a manual transmission is calculated, and an engine rotational speed is calculated. Is feedback-controlled to the target engine speed (rotational synchronization control). When the engagement of the clutch is detected by the clutch pedal switch, a predetermined delay time is set, and the rotation synchronization control is continued while limiting the increase in engine output during the delay time. It is possible to reduce the burden on the sync system when the gear change operation is performed with the clutch engaged while suppressing the shift shock even when the double clutch is operated.
[Selection] Figure 8

Description

  The present invention relates to a control device at the time of shifting in a vehicle (MT vehicle) including a manual transmission connected to an output side of an engine via a clutch.

Patent Document 1 calculates a target engine rotation speed required to travel at a target gear position after shifting by the shift operation of the manual transmission when the clutch release is detected, and calculates the engine rotation speed. A technique for calculating a shift shock while shortening a shift time by performing a rotation synchronization control for feedback control to a target engine rotation speed is described.
JP 2007-32341 A

  When performing the above-described rotation synchronous control of the manual transmission, as a clutch pedal switch for detecting whether the clutch is released or engaged, the clutch pedal switch is engaged at a position where the clutch pedal is further depressed from the position where the clutch is completely engaged (for example, OFF) is used. Basically, the rotation synchronization control is performed only when this switch detects the release (ON) of the clutch.

  By the way, there is a driver who performs a so-called double clutch operation during shifting. The double clutch operation is an operation of depressing the clutch pedal twice at the time of shifting, and is an action for eliminating a shift shock at the time of acceleration / deceleration.

  The double clutch operation is effective in a general MT vehicle that does not perform the rotation synchronization control. However, when the double clutch operation is performed by performing the rotation synchronization control, the clutch pedal is temporarily set even though the gear shift is actually performed. Since the switch is turned off, the rotation synchronization control is not performed during that time, and the rotation speed is once lowered. As a result, the shift time becomes longer, and in some cases, a shift shock occurs.

  Therefore, in Patent Document 1, the rotation synchronization control is forcibly continued for a predetermined time after the clutch engagement is detected during the rotation synchronization control, and the release of the rotation synchronization control by the double clutch operation is prevented, thereby preventing the shift shock. Is secured.

However, if the driver tries to engage the gear when the clutch is engaged during the double clutch operation, a burden is applied to the synchro member if the rotation synchronization control is continued.
The present invention has been made paying attention to such a conventional problem. In an MT vehicle that performs rotation synchronization control at the time of a shift, even if a double clutch operation is performed, the burden on the synchronization system is suppressed while suppressing a shift shock. Also aimed at reducing.

For this reason, the present invention
In a vehicle including a manual transmission connected to the output side of the engine via a clutch,
Clutch state detecting means for detecting whether the clutch is disengaged or engaged;
When release of the clutch is detected by the clutch state detection means, a target engine speed required to travel at the target gear position after the shift by the shift operation of the manual transmission is calculated, and the engine speed is calculated. Rotation synchronization control means for feedback control to the target engine rotation speed;
A delay time setting means for setting a predetermined delay time when engagement of the clutch is detected by the clutch pedal switch during the control of the rotation synchronization control means;
A delay-time rotation synchronization control means for executing the control of the rotation synchronization control means while limiting an increase in engine output during the delay time;
Is provided.

  In this way, when a double clutch operation is performed during a shift, the rotation synchronization control is performed while restricting the increase in engine output. Therefore, a gear change during the rotation synchronization control is performed while suppressing a shift shock. The burden on the synchro system can be reduced.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a system diagram of an MT vehicle showing an embodiment of the present invention.
An engine (internal combustion engine) 1 mounted on a vehicle is provided with an electrically controlled throttle valve 3 for controlling an intake air amount in an intake passage 2 thereof, and an opening degree thereof is controlled by an engine control unit (ECU) 4. Although illustration and description of the fuel supply system of the engine 1 are omitted, the supplied fuel amount is controlled by the ECU 4 so that a desired air-fuel ratio is obtained with respect to the intake air amount.

A manual transmission 6 is connected to the output side of the engine 1 via a clutch 5. The clutch 5 is released / fastened by the driver's clutch pedal operation, and is released when the driver steps on the clutch 5. The gear position of the manual transmission can be switched by a driver's shift lever (shift knob) operation.
Signals are input to the ECU 4 from various sensors.

The accelerator pedal sensor 11 detects the depression amount (accelerator opening) APO of the accelerator pedal and outputs a corresponding signal.
The crank angle sensor 12 outputs a signal synchronized with the rotation of the crankshaft of the engine 1, and can detect the engine speed NE from this signal.

The vehicle speed sensor 13 detects the vehicle speed (output shaft rotational speed of the transmission 6) VSP and outputs a corresponding signal.
The clutch pedal switch 14 outputs an ON / OFF signal corresponding to the position of the clutch pedal, and is turned on when the clutch is released (when the clutch pedal is depressed).

  The shift position sensor 15 outputs a signal corresponding to the position of the shift lever (shift knob). Specifically, the shift position sensor 15A outputs a signal corresponding to the position in the x direction (select direction) in FIG. It is composed of a stroke position sensor 15B that outputs a signal corresponding to the direction (stroke direction) position, and can determine the gear position (including the target gear position during gear shifting and the determination of gear engagement) by the signal output of these two direction positions. It is.

The neutral switch 16 is turned on when the shift lever is in the neutral region (see FIG. 4).
Further, a rotation synchronization control permission switch 17 is provided at the driver's seat or the like for selecting permission or prohibition of rotation synchronization control at the time of shifting according to preference, and an ON (permission) / OFF (prohibition) signal is also input to the ECU 4. Has been.

Further, an Nt sensor 18 for detecting the input shaft rotational speed Nt of the transmission 6 is provided, and the Nt signal is also input to the ECU 4.
Here, the ECU 4 determines the driver request torque based on the accelerator opening APO (and the engine speed Ne), and normally (during non-shifting), the target engine torque tTe = driver request torque. Based on the target engine torque tTe (and the engine speed Ne), a target throttle opening tTVO for obtaining this is calculated, and the opening of the electric throttle valve 3 is controlled according to the target throttle opening tTVO.

On the other hand, at the time of shifting, rotation synchronization control is performed in calculating the target engine torque tTe on condition that the rotation synchronization control permission switch 17 is ON.
Here, in the present invention, even when a double clutch operation is performed during a gear shift, it is possible to reduce the burden on the synchro system due to a gear change during the rotation synchronization control while suppressing the shift shock by the rotation synchronization control. Rotation synchronization control is performed.

Below, the rotation synchronous control at the time of the shift by ECU4 is demonstrated with the flowchart of FIG. 2, FIG.
FIG. 2 is a flowchart of a rotation synchronization control flag setting routine, which is executed every predetermined time.
The rotation synchronization control at the time of shifting by the ECU 4 will be described with reference to the flowcharts of FIGS.
FIG. 2 is a flowchart of a rotation synchronization control flag setting routine, which is executed every predetermined time.

In S1, it is determined whether or not the rotation synchronization control permission switch is ON. If it is OFF, the process proceeds to S2, and the rotation synchronization control flag F = 0 and the rotation synchronization control is prohibited.
If the rotation synchronization control permission switch is ON, the process proceeds to S3, and it is determined whether or not the rotation synchronization control flag F = 1 (during rotation synchronization control).
If the rotation synchronization control flag F = 0 and rotation synchronization control is not being performed, the process proceeds to S4.

In S4, it is determined whether or not the clutch pedal switch is ON (clutch disengagement). If the clutch pedal switch is OFF (clutch engagement), this routine ends.
If the clutch pedal switch is ON (clutch release), the process proceeds to S5.
In S5, it is determined whether or not the target gear position has changed based on the signal from the shift position sensor. For example, referring to FIG. 2, an example of a downshift from the 3rd speed to the 2nd speed will be described. When a shift from the 3rd speed to the neutral state is reached by the history of signals from the shift position sensor, the target position is reached. It is determined that the gear position has changed from the third speed to the second speed (the target gear position after the shift is the second speed).

If no change in the target gear position is recognized, this routine is terminated.
When the change of the target gear position is recognized, the process proceeds to S6, and after setting the target gear position after the shift, the rotation synchronization control flag F is set to 1 to start the rotation synchronization control.

Here, the flowchart of the rotation synchronization control routine of FIG. 3 will be described. This routine is also executed every predetermined time.
In S21, it is determined whether or not the rotation synchronization control flag F = 1. If F = 0, the process proceeds to S22 and normal engine torque control is executed.
When the rotation synchronization control flag F = 1, the process proceeds to S23, and travels at the target gear position after the shift from the target gear position (gear ratio GR) after the shift and the current vehicle speed (transmission output shaft speed) VSP. The target engine speed tNE (= VSP / GR), which is balanced with the vehicle speed, necessary for the calculation is calculated.

Next, in S24, the actual engine speed NE is detected.
Next, in S25, the actual engine speed NE is compared with the target engine speed tNE.

  If NE <tNE as a result of the comparison, the process proceeds to S26, where it is determined whether the delay is described later. If not, the target engine torque tTe is increased by the amount set according to the target engine speed tNE. Thus, by increasing the target engine torque tTe, the throttle opening degree TVO is increased, and the engine rotational speed NE is increased to approach the target engine rotational speed tNE.

  On the other hand, if it is determined that the delay is in progress, the value obtained by subtracting the torque-up limit amount set as will be described later from the normal upper limit value of the increase amount of the target engine torque tTe is corrected as the upper limit value in S27. The upper limit value is increased so as not to exceed the upper limit value, and the target engine speed tNE is brought closer to a speed slower than normal.

  On the other hand, if NE> tNE, the process proceeds to S28, where the target engine torque tTe is decreased to decrease the throttle opening TVO, to decrease the engine speed NE, and to approach the target engine speed tNE.

Returning to the flowchart of FIG.
After the rotation synchronization control flag F = 1 and rotation synchronization control is started, the process proceeds to S7 in the determination at S2.

In S7, it is determined whether or not the clutch pedal switch is turned off (clutch engagement). If the clutch pedal switch is turned off (clutch engagement), the process proceeds to S8.
In S8, it is determined whether or not the engine rotational speed NE has reached the target engine rotational speed tNE. If it is determined that the target engine rotational speed tNE has been reached by clutch engagement, there is no need to continue the rotation synchronization control. Therefore, the process proceeds to S2, and the rotation synchronization control flag F = 0 and the rotation synchronization control is prohibited.

If it is determined in S8 that the engine rotational speed NE has not reached the target engine rotational speed tNE, the process proceeds to S9, and it is determined whether or not gear engagement is confirmed.
Determination of gear engagement means that the operation to the target gear position has been completed, and determination is made based on the output of the shift position sensor. For example, referring to FIG. 4, an example of downshift from the 3rd speed to the 2nd speed will be described. It is determined that the gear enters the position. A predetermined range in which the signal output of the shift position sensor corresponds to the second speed position is separated from the neutral region. As a result, it is possible to reliably detect the gear engagement. Alternatively, it may be determined that the gear has been entered when the neutral region is set to the second speed side. In this case, the determination can be made simply by using the signal of the neutral switch.

  If it is determined that the gear is engaged, the clutch is not temporarily engaged by a double clutch operation in which the clutch is released and engaged a plurality of times in a short time. Therefore, the process proceeds to S15 without setting the delay time, and the rotation synchronization control flag F = As 0, the rotation synchronization control is terminated.

  If it is not determined that the gear is engaged, the process proceeds to S10, where it is determined whether or not the clutch pedal switch is switched from ON to OFF, and if it is the first time, the process proceeds to S11 and the delay time (delay remaining) is determined. Time) DL is set to a predetermined initial value DL0 (DL = DL0).

The delay time (initial value DL0) may be a fixed value for simplicity, but in this embodiment, as shown in FIG. 5, it is set to a small value as the engine rotational speed NE increases.
If it is not the first time, the process proceeds to S12, and a delay time (remaining delay time) DL is subtracted by a predetermined amount (ΔD) (DL = DL−ΔD) to measure the delay time.

  In next S13, it is determined whether or not the delay time (delay remaining time) DL is 0 or less, that is, whether or not the delay time has elapsed. If the delay time is within the delay time (when DL> 0), the process proceeds to S14 to synchronize rotation. In the control, the rotation synchronization control is continued while limiting the increase in engine output when the engine rotation speed is increased to the target rotation speed. As a technique for restricting an increase in engine output, in the first embodiment, a restriction amount for an increase amount of the engine torque is set and restricted. This limit amount may be a fixed value for simplicity, but is set to a smaller value as the amount of change of the target gear position toward the low speed stage is larger.

If it is determined in S13 that the delay time has elapsed (in the case of DL ≦ 0), the process proceeds to S15, where the rotation synchronization control flag = 0 and the rotation synchronization control is terminated.
If it is determined in S7 that the clutch pedal switch is ON (clutch disengagement), the process proceeds to S16, and it is determined whether the rotation synchronization control is continued (DL> 0) while limiting the engine output increase amount. To do.

  If it is determined in S16 that the rotation synchronization control is not being continued, that is, if the release state is maintained as it is after the clutch is released, the rotation synchronization control is continued without limiting the increase in engine output. .

  If it is determined in S16 that the rotation synchronization control with the engine output increase limited is being continued, the process proceeds to S17, where the restriction on the engine output increase is canceled, and the normal rotation synchronization control is switched to continue.

  In the present embodiment, the rotation synchronization control flag F is set to 1 based on the determinations at S4 and S5 in FIG. 2, and the portions that execute the control of S23 to S25, S27, and S29 in FIG. Corresponds to means. Further, based on the determination at S7 in FIG. 2, the part for setting the delay time DL at S10 corresponds to the delay time setting means, and when it is within the delay time, the determination at S13 is S14 (S28 in FIG. 3). Thus, the portion that continues the rotation synchronization control while limiting the increase in engine output corresponds to the rotation synchronization control means during delay.

FIG. 6 is a time chart in the case of normal clutch operation (Comparative Example 1) without delay.
After the clutch pedal is depressed and the clutch pedal switch is turned on, the target gear position is changed from, for example, the third speed to the second speed by a speed change operation. ), The target engine speed is set to the large side to balance the vehicle speed, the engine torque (throttle opening) is increased to bring the actual engine speed close to the target engine speed, and the clutch is engaged with the rotation balanced. Since it is fastened, a shift shock can be prevented and the shift time can be shortened. As a result, durability can be improved by reducing the synchro load, and cost can be reduced by reducing the synchro capacity.

FIG. 7 is a time chart in the case of a double clutch operation (Comparative Example 2) without delay.
After the clutch pedal is depressed and the clutch pedal switch is turned on, the target gear position is changed from, for example, the third speed to the second speed by a speed change operation. ), The target engine speed is set to the large side to balance the vehicle speed, and the engine torque (throttle opening) is increased to bring the actual engine speed close to the target engine speed. Once the clutch pedal switch is turned off and there is no delay, the rotation synchronization control is stopped and the engine rotation speed decreases. Thereafter, when the clutch pedal switch is turned on again, the rotation synchronization control is resumed, but it takes time to reach the target engine rotation speed. If the clutch is engaged before the engine rotational speed reaches the target engine rotational speed, a rotational speed difference is generated when the clutch is engaged, resulting in a shift shock. In other words, skill is required for double clutch operation.

FIG. 8 is a time chart when a double clutch operation is performed when shifting from the fourth speed to the third speed in the present embodiment.
After the clutch pedal is depressed and the clutch pedal switch is turned ON, the target gear position changes from the 4th speed to the 3rd speed by a shift operation. From that point, the target gear position after the shift (low speed side gear position) Thus, the target engine speed is set on the large side so as to balance the vehicle speed, and the engine torque (throttle opening) is increased so that the actual engine speed approaches the target engine speed.

  In the case of a double clutch, the clutch pedal switch is once turned OFF (clutch engagement), a delay time is set (S11), and the rotation synchronous control in which the increase in engine torque is limited by the torque-up limit amount during the delay time. Is continuously performed (S14).

  Therefore, even if a double clutch operation is performed, the gear change in the clutch engaged state (such as incomplete clutch depression for the second time) is achieved while maintaining the shift shock suppression function by continuing the rotation synchronization control. It is possible to reduce the load applied to the synchro system when (gear fastening) is performed.

In addition, after the gear engagement is confirmed, a good response can be obtained by terminating the rotation synchronization control without giving a delay time (S9 → S15).
If the clutch pedal switch is turned on again by the double clutch within the delay time, the engine output restriction due to the torque-up restriction amount is released, and the normal rotation synchronous control is resumed and continued.

  In this way, as long as the clutch is in a disengaged state that does not impose a burden on the synchro system due to gear changes, normal rotation synchronization control that does not limit the engine output is performed to bring the target rotation speed as close as possible. The shift shock suppression function can be maintained well.

  In the present embodiment, when the engine speed NE reaches the target engine speed tNE at the time of clutch engagement (S8 → S2), deterioration of fuel consumption can be prevented by prohibiting the rotation synchronization control.

  Further, when the engine speed is high, the intake air delay for engine blow-up when synchronizing the rotation speed by the double clutch operation is small, so the time until the clutch is engaged again is shortened. Therefore, as in this embodiment, the higher the engine speed is based on the characteristics of FIG. 5, the shorter the delay time is set, so that the rotation synchronization control is continued for the time corresponding to the actual double clutch operation. Thus, the fuel consumption can be maintained better.

  For example, as shown in FIG. 5, the delay time is preferably set to about 0.5 seconds when the engine rotational speed NE is 2000 rpm. If the time is set too long, the double clutch operation is not performed, and when the gear shift is completed by one clutch engagement operation, the engine rotation speed is kept high by the rotation synchronization control even after the clutch engagement. , Leading to worse fuel consumption.

For simplicity, the delay time may be set to a fixed value (for example, 0.5 seconds).
FIG. 9 is a time chart when the double clutch operation is performed at the time of shifting from the 4th speed to the 2nd speed in the present embodiment (for the sake of comparison, the case of the 4th speed → the 3rd speed is shown by a one-dot chain line).

  In this case, the torque increase limit amount in the rotation synchronous control during the delay is set to be smaller than that at the time of shifting from the fourth speed to the third speed. Thus, the lower the target gear position is, the higher the target engine rotational speed tNE after the shift is. Therefore, if the engine torque increase amount is limited too much, the effect of suppressing the shift shock is impaired. Therefore, the effect of suppressing the shift shock can be favorably maintained by reducing the torque-up limit amount as compared with the case of downshifting by one stage.

  Further, as described above, when a two-stage downshift is performed, since the amount of change in the target engine speed tNE before and after the shift is large compared to the first-stage downshift from the third speed to the second speed, the torque is increased. The limit amount may be reduced. That is, a configuration in which the limit amount of torque increase is made smaller as the number of gears to be shifted down to the low speed stage side is larger, or the limit amount of torque increase is made smaller alone or as the target gear position is at a lower speed stage. This can be performed in combination with the configuration to be performed.

FIG. 10 is a flowchart of a rotation synchronization control routine in the second embodiment in which the limit of the increase in engine output in the rotation synchronization control during delay is limited by the target rotation speed.
S31 to S35 are the same as S21 to S25 in FIG. 3, and when it is determined in S36 that the target engine speed tNE (= VSP / GR) after the shift is smaller than the actual engine speed NE (during downshift) In S37, it is determined whether the delay is in progress. If the delay is not in progress, the process proceeds to S37 as it is, and the target engine torque tTe is increased based on the target engine speed tNE so as to approach the target engine speed tNE. Rotation synchronous control is performed.

  On the other hand, if it is determined that the delay is being performed, a target rotational speed limit amount is set in S37, and the target engine speed tNE (= VSP / GR) is subtracted from the limit amount ΔtNE to obtain a new target engine speed. Set the speed tNE '.

During the delay, the rotational speed of the engine is synchronously controlled in S38 so that the actual engine speed NE approaches the limited target engine speed tNE ′.
FIG. 11 is a time chart when a double clutch operation is performed in the second embodiment.

  In this way, even if the target engine speed is limited to limit the increase in engine output, as in the case of the first embodiment, even when the double clutch is operated, the shift shock suppression effect is secured while the clutch is engaged. The effect that the burden to the synchro system by the gear change can be reduced is obtained.

  The limit amount of the target engine rotational speed may be a fixed value, but the larger the target engine rotational speed corresponding to the target gear position is, or the deviation between the engine rotational speed before the shift and the target engine rotational speed is It may be set to be variable such that the larger the value is, the smaller the value is.

  In the above embodiment, the throttle opening is controlled for engine torque control for rotation synchronization control. However, ignition timing control (engine torque reduction control by ignition timing retardation) may be used together. Good.

1 is an MT vehicle system diagram showing an embodiment of the present invention. Flowchart of rotation synchronization control flag setting routine Flow chart of rotation synchronization control routine Illustration of shift position sensor output The figure which shows the setting characteristic in the case of setting delay time variably. Time chart for normal clutch operation without delay Time chart for double clutch operation without delay Time chart in case of double clutch operation when shifting from 4th speed to 3rd speed in the first embodiment Time chart in case of double clutch operation when shifting from 4th speed to 2nd speed in the first embodiment Flowchart of a rotation synchronization control routine in the second embodiment Time chart in case of double clutch operation when shifting from 4th speed to 3rd speed in the second embodiment

Explanation of symbols

1 Engine 2 Air intake passage 3 Electric throttle valve 4 ECU
5 Clutch 6 Manual transmission 11 Accelerator pedal sensor 12 Crank angle sensor 13 Vehicle speed sensor 14 Clutch pedal sensor 15 Shift position sensor 16 Neutral switch 17 Rotation synchronization control permission switch

Claims (12)

In a vehicle including a manual transmission connected to the output side of the engine via a clutch,
Clutch state detecting means for detecting whether the clutch is disengaged or engaged;
When release of the clutch is detected by the clutch state detection means, a target engine speed required to travel at the target gear position after the shift by the shift operation of the manual transmission is calculated, and the engine speed is calculated. Rotation synchronization control means for feedback control to the target engine rotation speed;
A delay time setting means for setting a predetermined delay time when the engagement of the clutch is detected during the control of the rotation synchronization control means;
A delay-time rotation synchronization control means for executing the control of the rotation synchronization control means while limiting an increase in engine output during the delay time;
A control device for shifting a vehicle characterized by comprising:   The delay time is set when the engagement of the clutch is detected before the actual engine speed reaches the target engine speed after the release of the clutch is detected and the control of the rotation synchronization control means is started. The control device for shifting a vehicle according to claim 1.   The control device for shifting a vehicle according to claim 1, wherein the engine output increase limit amount is set according to a target gear position.   4. The control device for shifting a vehicle according to claim 3, wherein the limit amount for increasing the engine output is set to a smaller value as the target gear position is at a lower speed. 5.   The limit amount of the increase in engine output is set to a smaller value as the amount of change of the target gear position to the low speed stage is larger. Control device.   6. The rotation synchronization control is performed by releasing the restriction on the engine output increase when detecting that the clutch is released from the engaged state during the delay time. The control apparatus at the time of the gear shift of the vehicle as described in one.   The control device for shifting a vehicle according to any one of claims 1 to 6, wherein the delay time is set shorter as the engine speed is higher.   8. The control device for shifting a vehicle according to claim 1, wherein the increase of the engine output is limited by limiting an increase amount of the target engine torque.   The control device for shifting a vehicle according to any one of claims 1 to 7, wherein the limitation on the increase in engine output is to make the target engine rotation speed smaller than usual.   10. The control device for shifting a vehicle according to claim 9, wherein the limitation on the increase in engine output is set to a smaller value as the target engine speed is higher.   11. The vehicle speed change according to claim 9 or 10, wherein the limit of the engine output increase is set to a smaller value as the deviation between the target engine speed and the engine speed before the shift is larger. Control device at the time. Means for detecting the position of a shift lever for shifting the manual transmission;
The control device for shifting a vehicle according to any one of claims 1 to 11, wherein the target gear position is predicted based on a detection position during a shift operation of the shift lever.

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