JP2876820B2 - Integrated control device for automatic transmission and engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission, and more particularly to a device for integrally controlling an automatic transmission which may execute a clutch-to-clutch shift and an engine.

[0002]

BACKGROUND OF THE INVENTION In order to achieve a particular shift in an automatic transmission, it is often necessary to simultaneously engage and disengage two frictional engagement devices (a so-called clutch-to-clutch shift). In this case, if the synchronization of the engagement and disengagement of each friction engagement device is not properly achieved, the gear train of the automatic transmission instantaneously becomes rigid or neutral, and the output shaft torque is reduced. Descent and engine spikes occur.

For this reason, when such control is conventionally performed, a one-way clutch having a function substantially equivalent to the function of one of the friction engagement devices is provided to prevent such a problem from occurring. ing.

However, the method of synchronizing the respective friction engagement devices by using the one-way clutch as described above has problems such as an increase in weight and occupation of a housing space due to the provision of the one-way clutch. .

[0005] In view of the above, in recent years, the following technology has been disclosed as a technology for satisfactorily achieving such a "clutch-to-clutch shift" without using a one-way clutch (SAE). Paper 890529
).

According to this technique, when performing a so-called clutch-to-clutch shift control, one frictional engagement device is released and another frictional engagement device is engaged when a specific shift is achieved. For example, in the case of an upshift in a power-off state (a driven state in which power is transmitted from the wheel side to the engine side), first, the engine rotation speed is shifted by changing the synchronous rotation after shifting the frictional engagement device on the release side. The speed drops to near the speed, where the engagement side frictional engagement device is engaged.

[0007]

However, in practice, it is very difficult to perform the engagement on the engagement side when the engine rotation speed is near the synchronized rotation speed after shifting under various operating conditions. It is.

In this case, for example, when the engagement of the frictional engagement device on the engagement side is accelerated due to an upshift with the power off, a so-called overlap state occurs, and the output torque changes from negative to positive. A strong shift shock occurs.

For this reason, as a control mode, it is conceivable that the clutch-to-clutch shift is executed while the engagement of the friction engagement device on the engagement side is delayed so as to be in a so-called under-up state.

However, in this case, if the accelerator pedal is depressed even a little in this state, the engine rotational speed easily increases, and so-called engine squirting occurs.

The present invention has been made in view of such a problem, and in the case of a power-off clutch-to-clutch shift, even if the accelerator pedal is slightly depressed while the underlap control is basically performed, the engine starts rising. It is an object of the present invention to provide an integrated control device for an automatic transmission and an engine capable of preventing the above problem, and to solve the above problems.

[0012]

SUMMARY OF THE INVENTION As shown in FIG. 1, the present invention provides a system for integrally controlling an automatic transmission and an engine, in which a power-off clutch-to-clutch shift occurs in the automatic transmission. Means for detecting whether or not the engine is in a state, means for detecting whether or not the torque reduction of the engine is permissible, and the power-off clutch two-way.
When it is detected that a clutch shift is occurring, if the torque of the engine is in an allowable state, the gear is being shifted.
Of the engine torque running speed at underlap control while maintaining <br/> the throttle fully closed considerable torque, if the state where the torque down of the engine is restricted, when the
Means for executing a shift by overlap control in a state in which the engine torque is directly introduced into the automatic transmission , thereby solving the above problem.

[0013]

According to the present invention, in executing the power-off clutch-to-clutch shift, if a so-called overlap control is executed, a shift shock may occur. Therefore, the shift is basically executed by the underlap control. , in addition, in order to prevent the spouting up of the engine when the accelerator pedal is depressed in this state, during shifting all throttle the engine torque
A torque equivalent to closing is maintained .

As a result, even if the accelerator pedal is depressed in the underlap state, it is possible to suppress the engine from blowing up to a minimum.

Incidentally, the engine torque is not always in a state where it can always be reduced, and sometimes the engine torque cannot be reduced (that is, the throttle is fully closed).
(A considerable torque cannot be maintained) in some cases.

For example, in the case where the engine torque is reduced by retarding the ignition timing, the temperature of the catalyst usually rises. Therefore, when the temperature of the catalyst exceeds a certain value, the engine torque is reduced. Measures that prohibit the reduction of emissions are often adopted.

In the case where the automatic transmission and the engine are controlled by separate computers and a command signal for torque down control is transmitted from the automatic transmission control computer to the engine control computer in accordance with the shift control,
In some cases, disconnection or short-circuit of the signal line may occur. In this case, the engine torque is not reduced based on the fact that it is better not to reduce the engine torque at all than to reduce the engine torque based on the abnormal signal. It may be configured as follows.

[0018] Thus, when the engine torque is in a state that can not be reduced, Ro the engine torque
Control to maintain the torque equivalent to the fully closed
Because not come, when executed by directly underlap control clutch-would problem engine easily jetted raised by depressing the touch of the accelerator occurs.

In order to cope with this point, the present invention reduces the engine torque during the clutch-to-clutch shift under the condition that the engine torque can be reduced.
When the torque is maintained by the underlap control while maintaining the torque equivalent to the closing , and the torque reduction of the engine is restricted, under the restriction, that is, the engine at that time is controlled.
Under the condition that the torque is directly introduced into the automatic transmission.
The shift is executed by the overlap control.

Therefore, normally, there is almost no shift shock, and the shift can be executed in which the engine is prevented from being blown up. Even if the reduction of the engine torque is restricted, the shifts are not overlapped. Since the control is realized, it is possible to accurately prevent the engine from blowing up.

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2 is an overall schematic diagram of an integrated control device for an automatic transmission and an engine to which the present invention is applied.

The engine 1 has its injection valve 19 controlled by an engine control computer 7.
And the ignition timing at the distributor 20 are controlled, and an engine output corresponding to the accelerator opening (operating amount) of the accelerator pedal 22 and the engine speed is obtained.

That is, a main throttle valve 26 that opens and closes in conjunction with the movement of an accelerator pedal 22 and a motor driven by a command from the engine control computer 7 irrespective of the accelerator pedal 22 are provided in an intake pipe 24 of the engine 1. A sub-throttle valve 30, which is opened and closed in conjunction with the movement of the throttle valve 28, is arranged in series, and the function of the two throttle valves 26, 30 realizes the present invention.

More specifically, since the main throttle valve 26 is directly connected to the accelerator pedal, the accelerator operation amount and the engine output linearly correspond to each other, but the sub throttle valve 30 has its opening degree freely. Therefore, an equivalent throttle opening having intended characteristics as a whole can be obtained. Specifically, because they are in series,
It is controlled by the smaller of the two.

The automatic transmission 2 is controlled by the automatic transmission control computer 8 to operate the solenoid valves S1 to S1 of the hydraulic control device 3.
S3 is controlled, and as a result of the change of the oil passage in the hydraulic control device 3, the engagement state of each friction engagement device is selectively changed,
The shift speed corresponding to the vehicle speed and the accelerator opening can be obtained.

The engine control computer 7 has an engine rotation speed detected by an engine rotation sensor 9, an intake air amount detected by an intake air amount sensor 10, and an intake air temperature sensor 1.
1, the accelerator opening by the accelerator opening sensor 12, the vehicle speed by the vehicle speed sensor 13, the engine water temperature by the engine water temperature sensor 14, the brake switch 1
5 are input.

The engine control computer 7 determines the fuel injection amount and the ignition timing based on these signals.

On the other hand, the automatic transmission control computer 8 includes the accelerator opening sensor 12 and the vehicle speed sensor 1.
3. In addition to the signals from the engine water temperature sensor 14, the brake switch 15, etc., the position of the shift lever by the shift position sensor 16, the pattern select switch 17
Selection pattern such as fuel-consumption-oriented traveling or power-performance-oriented traveling, a signal for permitting shift to overdrive by the overdrive switch 18, and a turbine speed sensor 2 for detecting the input shaft rotation speed of the automatic transmission.
1 and the like, and the solenoid valves S1 to S3 are turned on so that a gear corresponding to the vehicle speed and the accelerator opening is obtained.
OFF control is performed.

FIG. 3 shows a transmission section of the automatic transmission 2. This transmission unit includes a torque converter 120, an overdrive mechanism 140, and an underdrive mechanism 160.

The torque converter 120 includes a pump 1
21, a turbine 122, and a stator 123, and includes a lock-up clutch 124.

The overdrive mechanism 140 includes a planetary gear set including a sun gear 143, a planetary pinion 142 meshing with the sun gear 143, a carrier 141 supporting the planetary pinion 142, and a ring gear 144 meshing with the planetary pinion 142. Prepared,
The rotational state of the planetary gear unit is controlled by a clutch C0, a brake B0, and a one-way clutch F0.

The underdrive mechanism 160 includes a common sun gear 161, planetary pinions 164 and 165 meshing with the sun gear 161, and the planetary pinion 1.
Ring gear 1 meshing with carriers 166 and 167 supporting planet 64 and 165 and planetary pinions 164 and 165
62, 163. The planetary gear set includes two sets of clutches C1, C2 and a brake B which determine the rotational state of the planetary gear set and the state of connection with the overdrive mechanism 40.
1, B3 and one-way clutch F2.

Each gear is achieved by engaging the clutches C0, C1, C2 and the brakes B0, B1, B3 as shown in FIG. 4 (indicated by a circle in FIG. 4). At this time, the one-way clutches F0 and F2 are operated (locked) at the time of driving (when power is transmitted from the engine to the wheels) at the position indicated by the mark ◎ in FIG.

Here, the shift from the second speed to the third speed is a so-called "clutch-to-clutch shift" in which the brake B1 is released and the clutch C2 is engaged.
Therefore, in this embodiment, the present invention is applied to the clutch-to-clutch shift from the second speed to the third speed when the power is off.

The control flow shown in FIG.
9 shows a flow of a power-off clutch-to-clutch upshift control to a speed position.

First, in step 210, various signals are read. Specifically, for example, the accelerator opening θ, the vehicle speed V, the selected position of the pattern select switch, and the like are read. In step 220, it is determined whether or not there is a shift determination, in particular, a shift from the second speed to the third speed. When there is no gear shift judgment,
If it is not determined to shift to the speed, the control flow is exited (returned).

In step 230, it is determined whether or not the power is off. Whether the power is off or not
The determination is made based on the vehicle speed V and the accelerator opening θ at that time.

When the power is not turned off, this control is not executed, so that the control flow is exited.

When it is determined in steps 220 and 230 that a power-off 2 → 3 (clutch-to-clutch) shift occurs, the process proceeds to step 240, in which it is determined whether the torque down control of the engine is being restricted. .

For example, when a disconnection or short circuit occurs in a signal line for transmitting a command signal for engine torque down control, a flag is set to regulate engine torque down control by a separately known control flow. Here, by reading the value of this flag, it is determined whether or not the engine torque down control is being restricted.

When the engine torque down control is being restricted, the routine proceeds to step 250, where the sub-throttle opening TH is controlled so that the engine output corresponds to the accelerator opening θ. In this case, in order to prevent the engine from being blown up, the two-to-three clutch two-clutch shift is executed in step 260 in the overlap control.

On the other hand, when the torque down control of the engine is not restricted, the sub throttle valve 30 is fixed to the fully closed state, and the engine torque down control is executed. As a result, even if the accelerator pedal is depressed, the engine can be prevented from blowing up.

Further, in this state, the 2 to 3 clutch-to-clutch shift is executed by underlap control (step 280).

The overlap control can be achieved by increasing the engagement of the clutch C1 with respect to the release of the brake B1, while the underlap control can be achieved by delaying this.

As shown in FIG. 6, from the second gear to the third gear
In the case of a power-off upshift to the second gear, brake B1
Is released and the clutch C2 is engaged. In this case, as shown by the solid line in the figure, if the engagement of the clutch C2 is advanced earlier than the release of the brake B1, so-called overlap control can be realized. Further, when the speed is reduced, the underlap control is realized (see the dashed line).

When the shift from the second speed to the third speed is performed by the underlap control, the automatic transmission is effectively in a neutral state, so that the engine torque must be reduced. The engine speed easily blows up. In this embodiment, since the engine torque is reduced while the underlap control is executed, it is possible to prevent the engine from blowing up without generating a shift shock.

If the engine torque cannot be reduced for some reason, the shift control is realized by the overlap control. In this case, too, the engine can be prevented from being blown up.

[0049]

As described above, according to the present invention, when the power-off clutch-to-clutch shift is executed, the underlap control is executed and the engine torque is reduced. A shift with a small shock and no engine blow-up can be realized. On the other hand, when the engine torque cannot be reduced for any reason, the shift is realized by the overlap control. It is possible to prevent the engine speed from rising.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the gist of the present invention.

FIG. 2 is an overall schematic view of a vehicle automatic transmission and an engine to which an embodiment of the present invention is applied.

FIG. 3 is a skeleton diagram showing a gear train of the automatic transmission.

FIG. 4 is a diagram showing an engagement state of a friction engagement device of the automatic transmission.

FIG. 5 is a flowchart showing a control flow executed by the apparatus of the embodiment.

FIG. 6 is a diagram showing shift transient characteristics that qualitatively show the effect of the embodiment of the present invention.

[Explanation of symbols]

 B1 ... disengagement side frictional engagement device, C2 ... engagement side frictional engagement device, 22 ... accelerator pedal, 26 ... main throttle valve, 28 ... motor, 30 ... subthrottle valve, 12 ... accelerator opening sensor, 13 ... vehicle speed Sensor.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-46361 (JP, A) JP-B-47-20291 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60K 41/04 F02D 29/00 F02D 41/00 F16H 61/06

Claims (1)

(57) [Claims] An apparatus for integrally controlling an automatic transmission and an engine, means for detecting whether or not a power-off clutch-to-clutch shift occurs in the automatic transmission, and allowing a decrease in engine torque. Means for detecting whether or not the engine is in a state, and when it is detected that the power-off clutch-to-clutch shift is occurring, if the engine torque can be tolerated, the engine torque during the shift is equivalent to full throttle closing Of torque
Running speed at underlap control while maintaining, in the case of a state where the torque down of the engine is restricted, its
The engine torque at the time of
Means for performing a shift by overlap control in a closed state , and an integrated control device for an automatic transmission and an engine.