JPH1047102A - Integrated control device for transmission and engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce shift shock by carrying out control so as to prevent a vehicle from driving by an engine, in a device for controlling engine speed at the time of shift-down. SOLUTION: When shift-down is commanded, an idle speed control valve(an ISC valve) is opened to a prescribed opening, and engine speed is raised. Detecting values of an engine speed sensor 26 and a turbine speed sensor 28 are monitored while connection of a clutch for selecting a low gear is started really from its time point. In the case where the engine speed exceeds the turbine speed, the opening degree of the ISC valve 2 is reduced to a prescribed rate, and the engine speed is reduced. Control is carried out so as to prevent a vehicle from driving by an engine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated control device for an engine and a transmission for integrating and controlling an engine and a transmission for shifting and outputting the output of the engine. Related to control.

[0002]

2. Description of the Related Art Since an engine has a relatively narrow range of usable rotational speeds, it is often used with a transmission in which a plurality of speed ratios can be selected. In particular, when used in vehicles such as automobiles, the range of the number of rotations and the range of the loaded weight are wide, and the engine is generally used in combination with a multi-stage transmission having several to several tens of gears.
Then, a gear having an appropriate gear ratio is selected according to use conditions such as the speed of the vehicle, the gradient of the road, and the weight.

When the selected gear is changed, that is, at the time of gear shifting, the ratio between the number of revolutions of the engine and the number of revolutions of the output shaft of the transmission changes before and after the gear shifting, and this change causes a so-called shift shock. In a conventional transmission, particularly in an automatic transmission, when a new gear is selected (when a gear is changed), a clutch for selecting a gear is gradually engaged to prevent a rapid change in rotation speed. To reduce shift shock. However, excessively performing the operation of gradually connecting in this way shortens the life of the clutch,
Another problem is that the driver gives a dull impression as if the clutch had slipped. In particular, when downshifting to a lower gear ratio when the vehicle is decelerating, the engine brake may be applied, giving the driver and other passengers an unpleasant impression.

Japanese Patent Application Laid-Open No. 63-284039 discloses a device that, when downshifting during deceleration, increases engine torque in synchronization with downshifting to reduce shift shock due to engine braking. This device connects an upstream side and a downstream side of an engine throttle valve, and includes an idle speed control valve (hereinafter, referred to as an ISC valve) provided in a bypass that bypasses a slot valve and guides air to the engine. The engine torque is increased by opening a predetermined amount.

[0005]

In the apparatus described in the above-mentioned publication, there is a case where the engine torque is excessively increased in downshifting at the time of deceleration due to product variation such as an ISC valve. In this case, when the actual shift starts, that is, when the gear selection clutch starts to be engaged, the increased engine torque works to increase the vehicle speed, and also in this case, there is a problem that a shift shock occurs. .

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a transmission and an engine capable of reducing a shift shock generated at the time of downshifting during deceleration by accurately controlling the engine. It is an object of the present invention to provide an integrated control device.

[0007]

In order to achieve the above-mentioned object, an integrated control device for a transmission and an engine according to the present invention comprises: an engine; and a driving force of the engine which is selected from a plurality of speed ratios. An integrated control device for a transmission and an engine that integrates and controls a transmission that outputs by shifting at a different ratio, wherein the engine controls a predetermined physical quantity related to the operation of the engine to control the rotation speed of the engine. Control means;
Shift instructing means for instructing a change in the gear ratio of the transmission, drive state detecting means for detecting whether the engine is driving the transmission, and shift start detecting means for detecting that the shift has actually started And When the drive state is not detected by the drive state detection means, the engine control means performs control to increase the engine speed by a predetermined number of revolutions thereafter when an instruction to reduce the gear ratio is issued by the speed change instruction means. In addition, the engine control unit detects the drive state by the drive state detection unit after the instruction to reduce the gear ratio is issued and before the shift start detection unit detects the start of the shift. Control for lowering the engine speed.

According to this configuration, the engine is not driven at the time of the start of the actual shift, so that the occurrence of a shift shock in the direction in which the vehicle accelerates can be suppressed.

[0009] Further, there is provided storage means for storing at least one of the physical quantities at the time when the shift start is detected by the shift start detecting means, and the engine control means controls the next increase in the engine speed. In the above, the engine speed may be controlled based on the stored physical quantity.

According to this configuration, since the control can be performed by learning the previous value from the next time, the shift shock can be more effectively suppressed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment (hereinafter, referred to as an embodiment) of an integrated control device for a transmission and an engine according to the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram schematically showing a control device of this embodiment mounted on a vehicle, and an engine and a transmission controlled by the control device. The output of the engine 10 is transmitted to the transmission 14 via the torque converter 12 and further transmitted to driving wheels (not shown) to drive the vehicle. The transmission 14 is an automatic transmission having four types of transmission gears. The intake system of the engine 10 is provided with a throttle valve 16, and the output of the engine 10 is controlled by the opening of the slot valve 16. Further, a bypass 18 that communicates between the upstream side and the downstream side of the throttle valve 16 and bypasses the throttle valve 16 is provided. The bypass 18 is provided with an idle speed control valve (ISC valve) 20. IS
The C valve 20 is a valve for adjusting the number of revolutions of the engine 10 during idling. During idling, the throttle valve 16 is fully closed and the bypass 1
Air passing through 8 is drawn into the engine. By adjusting the intake air amount by the opening of the ISC valve 20, the engine speed is controlled to a predetermined value.

An engine electronic control unit (hereinafter referred to as an electronic control unit) for controlling the engine by controlling the fuel injection amount and the like based on the intake pipe negative pressure, the engine speed, the cooling water temperature, etc., including the control of the ISC valve 20. Is referred to as ECU) 22
Is provided. Further, a transmission ECU 2 for selectively controlling a transmission gear based on a vehicle speed, an opening of a throttle valve, and the like.
4 are provided. Engine ECU 22 and transmission EC
Data is exchanged between the U24s, so that when a gear is changed, the output of the engine is controlled so that a smooth gear change is performed.

Further, in this apparatus, an engine speed sensor 26 for detecting the engine speed and a turbine speed sensor 28 for detecting the speed of the turbine of the torque converter 12 are provided. In this embodiment, the engine speed sensor 26 includes a toothed pulley provided on the crankshaft and a pickup that detects passage of the toothed portion. On the other hand, the turbine speed sensor 28 detects the transmission 1 that rotates at the same speed as the turbine.
4 comprises a gear provided on the input shaft and a pickup for detecting passage of gear teeth. Further, a storage unit 30 that stores variables used in the previous control is provided in the engine ECU 22 for use in the next control.

The device according to the present embodiment controls the engine speed by opening the ISC valve 20 when the downshift control is performed during deceleration of the vehicle, thereby preventing the occurrence of a shift shock due to engine braking or engine torque. Restrained. Specifically, when a downshift instruction is issued, the engine speed is reduced by the torque converter 12.
The turbine speed is raised to an extent that is substantially the same so as not to be higher than the turbine speed. Thus, when the clutch for actually selecting the lower gear starts engaging, the difference between the rotation speeds of the engine and the turbine is reduced, thereby reducing the shift shock caused by the rotation speed difference. Further, even during the period from when the clutch starts to be connected to when the clutch is completely connected, control is performed in a direction to increase the engine speed to reduce shift shock caused by the engine brake.

Regarding the above-described downshift control during deceleration, a downshift from the 4th gear to the 3rd gear (4
(-3 shift) will be described as an example. FIG.
FIG. 3 is a control flowchart of three shifts, and FIG. 3 is a chart showing a time change of each control element at this time.

First, it is determined whether the vehicle is in a decelerating state (S100). The deceleration state is detected when the throttle valve 16 is fully closed. This state is a state where the engine 10 is driven by the inertia of the vehicle, that is, a state where the engine brake is applied. Referring to FIG. 3, the engine speed _NE is greater than the turbine speed _NT of the torque converter. Due to this difference in the number of revolutions, the drive wheel torque T becomes negative (see FIG. 3), that is, the engine brake is applied. In this state, the ISC valve 20 is in a closed state. Further, the fail cut signal becomes Hi, and the supply of fuel to the engine 10 is stopped.

Next, it is determined whether the transmission ECU 24 has issued an instruction to change the gear from the fourth gear to the third gear (downshift in this example) (S10).
2). Therefore, the transmission ECU 24 functions as a shift instruction means. Instruction timing of the downshift, a time t ₁ in FIG. If the downshift has not been completed (S104), the following engine control is performed.

First, the fail cut signal for stopping the fuel supply to the engine 10 is set to Lo, and the fuel supply is restarted (S106). Further, it is determined whether the clutch for selecting the lower gear, that is, in this example, the third gear is started to be engaged, and the actual downshift is started (S1).
08). Immediately after the downshift instruction is issued, the clutch for selecting the fourth gear is in the engaged state, and the actual downshift has not been started yet. In this case, the opening set value MNISC of the ISC valve 20 is set to a predetermined value at the fourth speed. Thus, ISC valve 20 is opened a predetermined amount, increasing the total intake air amount of the engine 10 by intake air passing through the bypass 16, the engine speed N _E and drive wheel torque T is increased. The reason for increasing the drive wheel torque T in this way is to reduce a shock when the clutch of the third speed gear is engaged. That is, if the engine speed _NE and the turbine speed _NT match, the engine 10 is not in a state in which the vehicle is being driven and the engine is not braked, so that the engine 10 is in a neutral state. This is because the shock when the clutch is engaged is minimized.

Next, it is determined whether the flag F1 is 0 (S112). This flag F1 is set to I
This flag indicates that the adjustment of the SC valve 20 has already been performed at the time of the current downshift. Flag F1 is 0
Indicates that the ISC valve 20 has not been adjusted in the past.

When the flag F1 is 0, it is determined whether or not the engine 10 is driving the vehicle (hereinafter simply referred to as a driving state) (S114). This determination is performed by comparing the engine speed N _E and the turbine speed N _T, when the engine speed N _E exceeds the turbine speed N _T,
The driving state is determined. Thus, the engine speed sensor 26, the turbine speed sensor 28 and the engine E
The CU 22 functions as drive state detection means. The driving state, in FIG. 3, a state of near time t _2, the
The drive wheel torque T is also a positive value. The opening degree of the ISC valve 20 is determined so as not to be in such a driving state. However, depending on the product accuracy of the ISC valve 20, the driving state may be such as when the valve is opened slightly larger. .

When the driving state is detected, the correction amount GISCi-1 of the ISC valve opening is changed by a predetermined amount Δ, and the GI
SCi (S116), and a flag F1 indicating that the adjustment of the ISC valve 20 has already been performed at the time of the current downshift is set (S118). ISC valve opening correction amount GISCi-1 is a correction amount used when the previous shift change, by learning the past values, to determine the correction amount at an early stage, soon the engine rotational speed N _E Can be reduced until a non-driving state is reached.
The correction amount GISCi calculated here is stored in the storage unit 30 provided in the engine ECU, and is referred to at the time of the next downshift control.

Then, the opening command value ISC of the ISC valve is calculated by the following equation (S120).

By Equation 1] ISC = MNISC-GISCi ... (1 ) correction amount GISCi, by setting value MNISC is reduced, the opening degree is reduced of the ISC valve 20, the drive wheel torque T and the engine from the time t ₂ in FIG. 3 The number of revolutions _NE decreases, and the non-drive state is controlled. Further, the control width Δ is small, even when the engine speed N _E to a non-driving state is not decreased at once, during several times after the downshifting, undriven state by the above-described learning effect Will be controlled. If the drive state is not determined in step S114 and the correction amount GISCi is also 0, the set value MNISC becomes the opening command ISC of the ISC valve 20 as it is.

If it is determined in step S108 that the shift has actually been started, the process proceeds to step S122. The actual shift start (actual shift start), as at time t ₃ in FIG. 3, the turbine rotational speed N _T is determined by began to rise. At this time, the connection of the clutch of the fourth speed gear is completely released, and the connection of the clutch of the third speed gear is started. At this time, if the engine rotational speed N _E is substantially equal to the turbine speed N _T, shift shock is reduced. Further, in the present embodiment, in particular as the engine speed N _E does not exceed the turbine speed N _T. This is because when the positive torque is generated as indicated by the broken line between time t ₂ in FIG. 3 at time t _3, even though the vehicle is decelerating, since it is a short time, but vehicle accelerates This is for preventing the driver from feeling uncomfortable. Further, even if a slight amount of negative torque is generated, the vehicle is not decelerating because the vehicle is decelerating. Thus, the turbine speed sensor 28 and the transmission ECU 2
4 functions as a shift start detecting means.

When the engagement of the clutch of the third gear is started, the opening set value MNISC of the ISC valve 20 is changed to a predetermined value for the third gear (S122).
Then, the flag F1 is returned to 0 (S124). And
The process proceeds to step S120, and the opening command value ISC is calculated by equation (1). At this time, the correction value GI
If SCi is non-zero, this value will modify it,
As shown in FIG. 3, the opening of the ISC valve 20 is reduced from the time t _{3 as} shown by the solid line. The reason why the ISC valve 20 is opened when the third speed gear is selected is to reduce the shift shock. The reason is as follows. Although the engine speed increases due to the inertia of the vehicle due to the downshift, the vehicle is decelerated, which is a shift shock. In order to reduce this, the engine 10 is controlled to accelerate itself.

If it is determined in step S104 that the shift has been completed, the opening command value ISC of the ISC valve 20 is determined.
And the flag F1 is set to 0 (S126, S128), and returns to the initial value. Thus, the downshift operation is completed, the ISC valve 20 is closed, and the fuel cut is restarted.

In the present embodiment, the drive state detecting means performs the detection based on the difference between the engine speed and the turbine speed. However, a torque sensor is provided on the crankshaft or the like, and the drive state is detected based on the torque of the crankshaft or the like. -It is also possible to detect a non-driving state. Further, the shift start time can be obtained from the stroke of the gear selection clutch, and in the case of a hydraulically controlled clutch, it can also be obtained from this change in hydraulic pressure.

Further, in the present embodiment, the integrated control device for controlling the engine and the transmission mounted on the vehicle has been described. However, the same control can be performed even when the integrated control device is not mounted on the vehicle.

[0029]

As described above, according to the present invention, since the engine is not driven at the start of the actual shift, the occurrence of a shift shock in the direction in which the vehicle accelerates can be suppressed. Further, the shift shock can be more effectively suppressed by learning the previous value and performing control from the next time.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of an embodiment of a transmission, an engine, and an integrated control device thereof according to the present invention.

FIG. 2 is an example of a control flowchart of the present embodiment.

FIG. 3 is a time chart illustrating an operation state of each unit of the apparatus according to the embodiment.

[Explanation of symbols]

10 engine, 14 transmission, 16 throttle valve, 20 ISC valve, 22 engine ECU, 24
Transmission ECU, 26 Engine speed sensor, 28
Turbine speed sensor, 30 storage unit.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Koji Taniguchi 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (2)

[Claims] 1. An integrated control device for a transmission and an engine, which integrally controls an engine and a transmission that shifts and outputs a driving force of the engine at a speed ratio selected from a plurality of speed ratios. An engine control means for controlling a predetermined physical quantity related to the operation of the engine to control the number of revolutions of the engine; a shift instruction means for instructing a change in a gear ratio of the transmission; and the engine driving the transmission. A drive state detecting unit that detects whether the vehicle is in a state, and a shift start detecting unit that detects that a shift has actually started. The engine control unit detects a drive state by the drive state detecting unit. When the speed change ratio is not instructed by the speed change instructing device when the speed is not being changed, control for increasing the engine speed by a predetermined number of revolutions is performed thereafter. When the driving state is detected by the driving state detecting means between the time when the speed ratio is instructed and the start of the gear shift is detected by the shift start detecting means, control is performed to lower the engine speed. , Transmission and engine integrated control device. 2. The integrated control device for a transmission and an engine according to claim 1, further comprising storage means for storing at least one of said physical quantities when a shift start is detected by said shift start detection means. And an integrated control device for a transmission and an engine, wherein the engine control means controls the engine speed based on the stored physical quantity in the next control for increasing the engine speed.