JP3004781B2 - Engine control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine control device,
In particular, the present invention relates to an engine control device in a vehicle having an automatic transmission.

[0002]

2. Description of the Related Art Generally, automatic transmissions mounted on vehicles are
A combination of a torque converter and a speed change mechanism, wherein a power transmission path of the speed change mechanism is switched by selectively engaging a plurality of friction elements such as a clutch and a brake to automatically shift to a predetermined speed. In this type of automatic transmission, for example, a shift pattern is set in advance using, for example, a throttle opening degree representing an engine load and a vehicle speed as parameters, and this shift pattern is compared with an actual operating state to determine an operating state. The optimum gear position is selected according to the speed.

On the other hand, in a vehicle equipped with this type of automatic transmission, the slip of the driving wheels is determined in order to prevent the driving force transmitted to the driving wheels from being excessive with respect to the friction coefficient of the road surface. A traction control system that automatically controls the driving force at times in a restraining direction has been put to practical use. In the traction control, a slip amount is calculated based on the drive wheel speed and the vehicle speed, and the calculated slip amount is compared with a preset reference value to determine a slip state of the drive wheel. By reducing the throttle opening, the engine output is reduced to suppress transmission of excessive driving force to the driving wheels.

[0004]

Conventionally, the output of the engine is adjusted without considering the operating characteristics of the torque converter provided in the automatic transmission. A problem could occur.

[0005] That is, conventionally, when the drive wheels are in a slip state, the engine output is reduced by reducing the throttle opening as shown in FIG. As shown in FIG. 3B, the ratio of the output rotation speed to the input rotation speed in the torque converter, that is, the speed ratio e
When There close to 1, as shown in FIG. (C), the speed ratio e and the engine speed N _E is accidentally overshoots the target rotational speed N ₀ may exceed temporarily 1, from the drive wheel The reverse driving force transmitted to the engine via the automatic transmission may cause the engine output to decrease too much, thereby deteriorating the traveling performance.

Further, as described above, the engine speed N _E
When the speed ratio e exceeds 1 due to a decrease in the engine speed, the engine speed is then reduced to a specific gear position of the automatic transmission, for example, a gear position involving a one-way clutch such as the first or second speed in the D range. when the N _E is restored, the speed ratio e is a one-way clutch idles at the moment of passing through the 1 a power transmission state, abruptly driving force would feel uncomfortable to the driver is generated.

SUMMARY OF THE INVENTION The present invention addresses the above-described problem in a vehicle having an automatic transmission, and has as its object to perform optimal engine control that reflects the speed ratio of a torque converter.

Japanese Patent Application Laid-Open No. 62-276235 discloses a configuration in which the larger the speed ratio of the torque converter at the time of engine deceleration, the larger the intake air amount is.
This is for the purpose of preventing engine stall due to reverse driving force acting on the engine via the automatic transmission during deceleration, and is different from the technical problem to be solved from the present application.

[0009]

That is, an engine control apparatus according to the invention of claim 1 of the present application (hereinafter referred to as first invention), as shown in FIG. 1, receives an input to a transmission mechanism via a torque converter. Ratio calculation for calculating the speed ratio of the torque converter in the automatic transmission in a vehicle provided with an automatic transmission for transmitting the engine output to the drive wheels and provided with engine output adjusting means A for adjusting the engine output. Means B and output adjustment speed changing means C for changing the output adjustment speed by the engine output adjustment means A according to the speed ratio calculated by the calculation means B.

The invention of claim 2 of the present application (hereinafter referred to as the second invention)
The engine control device according to the present invention includes an automatic transmission that transmits the engine output input to the transmission mechanism via the torque converter to the drive wheels, and adjusts the engine output, as in the first invention. In the vehicle provided with the engine output adjusting means A, the engine output adjusting means A serves as a throttle adjusting means for adjusting the opening of a throttle valve provided in an intake passage of the engine, and a torque converter of the automatic transmission. A speed ratio calculating means for calculating a speed ratio; and an operating gain changing means for changing an operating gain of the throttle adjusting means according to the speed ratio calculated by the calculating means. .

An engine control apparatus according to a third aspect of the present invention (hereinafter, referred to as a third aspect of the invention) is an automatic transmission for transmitting an engine output input to a transmission mechanism via a torque converter to drive wheels. And a vehicle provided with engine output adjusting means A for adjusting the engine output, wherein the engine output adjusting means A is a throttle adjusting means for adjusting the opening of a throttle valve provided in an intake passage of the engine. Speed ratio calculating means C for calculating the speed ratio of the torque converter in the automatic transmission.
And an operating gain changing means C for decreasing the operating gain of the throttle adjusting means A as the speed ratio increases when the speed ratio calculated by the calculating means C is 1 or less. .

Further, an engine control apparatus according to a fourth aspect of the present invention (hereinafter referred to as a fourth aspect) is an automatic transmission for transmitting an engine output input to a transmission mechanism via a torque converter to driving wheels. And a vehicle provided with engine output adjusting means A for adjusting the engine output, wherein the engine output adjusting means A is a throttle adjusting means for adjusting the opening of a throttle valve provided in an intake passage of the engine. Speed ratio calculating means B for calculating the speed ratio of the torque converter in the automatic transmission
When the speed ratio calculated by the calculating means B is 1 or less, an operating gain changing means C for decreasing the operating gain of the throttle adjusting means A as the speed ratio increases, and a transmission mechanism in the automatic transmission. In a power transmission state in which a one-way clutch that transmits the engine output to the drive wheels in one direction is provided, the speed ratio calculated by the calculation means B is changed from a state of 1 or more to a state of 1 or less. An operation gain lowering means D for reducing the operation gain of the throttle adjusting means A at the time of shifting is provided.

Further, the invention of claim 5 of the present application (hereinafter referred to as a fifth invention)
The engine control device according to the present invention includes an automatic transmission that transmits an engine output input to a transmission mechanism via a torque converter to driving wheels, and is provided with engine output adjusting means A for adjusting the engine output. In the vehicle, the engine output adjusting means A is a throttle adjusting means for adjusting an opening of a throttle valve provided in an intake passage of the engine, a slip detecting means E for detecting a slip state of a driving wheel, and a driving wheel The throttle adjusting means A so as to suppress the slip state when the vehicle slips.
, A speed ratio calculating means B for calculating a speed ratio of the torque converter in the automatic transmission, and a speed ratio calculated by the speed ratio calculating means when the traction control means F is operated. Operating gain changing means C for changing the operating gain of the throttle adjusting means.

[0014]

[0015]

According to the first aspect of the present invention, since the adjusting speed of the engine output is changed in accordance with the speed ratio of the torque converter, the engine speed is rapidly reduced near the speed ratio of 1. As a result, the engine speed hardly drops to the reverse drive range (e> 1), thereby avoiding deterioration of the traveling performance.

According to the second invention, the operation gain of the throttle valve is changed according to the speed ratio of the torque converter, so that the same effect as in the first invention can be obtained.

According to the third and fourth aspects of the present invention, when the speed ratio is 1 or less, the operation gain of the throttle adjusting means decreases as the speed ratio increases. A similar effect can be obtained.

Further, according to the fourth invention, when the power transmission state in which the one-way clutch provided in the transmission mechanism of the automatic transmission is involved, the speed ratio of the torque converter shifts from a state of 1 or more to a state of 1 or less. When this happens, the operating gain of the throttle adjusting means will be reduced, so even if the engine speed is reduced too much to the reverse drive range, the engine speed is restored and torque transmission is resumed. Is prevented.

According to the fifth aspect, the operation gain of the throttle adjusting means is changed in accordance with the speed ratio at the time of traction control, so that an excessive decrease in the engine speed is suppressed. It is possible to avoid the deterioration of the traveling performance due to the synergistic effect of the engine brake with the decrease in the driving force due to the traction control.

[0020]

[0021]

[0022]

Embodiments of the present invention will be described below.

As shown in FIG. 2, a vehicle 1 according to this embodiment has left and right front wheels 2 and 3 as driving wheels,
The output torque of the engine 4 is changed from the automatic transmission 5 to the differential device 6.
And transmitted to the front wheels 2 and 3 via the left and right drive shafts 7 and 8.

An intake passage 9 of the engine 4 has an air flow sensor 10 for detecting the amount of intake air, and a main throttle valve 1 whose opening changes in association with an accelerator pedal 11.
2 and a sub-throttle valve 14 driven to be opened and closed by a throttle actuator 13. Basically, the main throttle valve 12 adjusts the amount of intake air in accordance with the amount of depression of the accelerator pedal 11, thereby adjusting the engine output. When the opening degree is controlled to be smaller than that of the valve 12, the intake air amount is limited by the sub-throttle valve 14, so that control for lowering the engine output is possible.

On the other hand, as shown in FIG. 3, the automatic transmission 5 includes a torque converter 20 connected to the output shaft 15 of the engine 4, a transmission mechanism 30 to which the output torque is input, and a transmission mechanism 30. Frictional elements 41 to 46 and one-way clutches 51 and 52 such as clutches and brakes for switching the power transmission path of
And a hydraulic control circuit 60 that controls supply and discharge of the line pressure supplied to the line 46.

The torque converter 20 includes a pump 22 fixed in a case 21 connected to the engine output shaft 15, and a turbine 23 opposed to the pump 22.
And a stator 25 supported by the transmission case 16 via a one-way clutch 24 to increase the torque, and a lock-up clutch 26 provided between the case 21 and the turbine 23. Then, the turbine 23
Is output to the transmission mechanism 30 via the turbine shaft 27. Here, a pump shaft 17 that penetrates through the inside of the turbine shaft 27 is connected to the engine output shaft 15, and the shaft 17 drives an oil pump 18 provided at the rear end of the transmission.

On the other hand, the speed change gear mechanism 30 is constituted by a well-known Lapinho type planetary gear device, and has a small diameter small sun gear 3 loosely fitted on the turbine shaft 27.
1 and a large-diameter large sun gear 32 loosely fitted on the turbine shaft 27 also behind the sun gear 32.
A plurality of short pinion gears 33 meshed with the small sun gear 31, a front half of which is meshed with the pinion gear 33 and a rear half of which is the large sun gear 3.
2, a long pinion gear 34, a carrier 35 rotatably supporting the long pinion gear 34 and the short pinion gear 33, and a ring gear 36 meshed with the front half of the long pinion gear 34.

A forward clutch 41 and a first one-way clutch 51 are connected in series between the turbine shaft 27 and the small sun gear 31, and a coast clutch 42 is provided in parallel with the clutches 41 and 51. A 3-4 clutch 43 is interposed between the turbine shaft 27 and the carrier 35, and the turbine shaft 27 and the large sun gear 3
2, a reverse clutch 44 is interposed. Further, between the large sun gear 32 and the reverse clutch 44, a 2-4 brake 45 which is a band brake for fixing the large sun gear 32 is provided, and between the carrier 35 and the transmission case 16 is provided. , A second one-way clutch 5 for receiving the reaction force of the carrier 35
2 and a low reverse brake 4 for fixing the carrier 35
6 are provided in parallel. The rotational power is output via the output gear 12 connected to the ring gear 36.

The following table 1 summarizes the relationship between the operation of each of the friction engagement elements 41 to 46 and the one-way clutches 51 and 52 and the shift speed.

[0030]

[Table 1] As shown in FIG. 2, a control unit (hereinafter referred to as an ECU) for integrally controlling the engine 4 and the automatic transmission 5 is provided.
The ECU 70 includes a wheel speed sensor 71 that detects the rotational speed of the left and right front wheels 2 and 3.
72, a signal from the air flow sensor 10, a signal from a throttle opening sensor 73 for detecting the opening of the main throttle valve 12, and an engine speed sensor 74 for detecting the speed of the engine output shaft 15. , A signal from a turbine speed sensor 75 for detecting the output speed (turbine speed) of the torque converter 20, a signal from a vehicle speed sensor 76 for detecting the vehicle speed of the vehicle, and a select position by the select lever 19. , The engine output control by the throttle actuator 13 provided in the engine 4 and the shift control by the shift solenoids 61 to 61 provided in the hydraulic control circuit 60 are performed. It has become.

The shift control performed by the ECU 70 will be briefly described. The ECU 70 receives a signal from the throttle opening sensor 73 and a signal from the vehicle speed sensor 76, and sets the throttle opening and the vehicle speed in advance as parameters. The downshift and upshift are determined by comparing the actual throttle opening θ and the vehicle speed V indicated by the signals from the sensors 73 and 76 on the shift map set as, and the determined shift stage G is obtained. The transmission mechanism 30 is controlled via the transmission solenoids 61 to 61 as described above.

Next, the engine output control, which is a feature of the present invention, will be described. Specifically, the engine output control is performed as follows in accordance with the flowchart of FIG.

That is, after reading various signals in step S1, the ECU 70 reads the slip amount S in step S2.
Is calculated. That is, the ECU 70 selects, for example, the larger one of the wheel speeds of the left and right front wheels 2 and 3 indicated by the signals from the wheel speed sensors 71 and 72, and selects the wheel speed and the vehicle speed V indicated by the signal from the vehicle speed sensor 76. Is calculated as the slip amount S.

After calculating the slip amount S, the ECU 70 proceeds to step S3 to determine whether or not the slip amount S is 0. If the determination is NO, the ECU 70 proceeds to step S4, where the engine speed _NE and the turbine speed N _The speed ratio e is calculated from _T, and in step S5, FIGS.
As shown in (5), the target charging efficiency _CE0 is set according to a map previously set based on the vehicle speed V, the shift speed G, the slip amount S, and the speed ratio e. As shown in FIG. 5A, the map showing the target charging efficiency C _E0 shows a tendency to increase as the vehicle speed V increases as shown in FIG. ), The larger the shift speed G, the lower the tendency. The slip amount S is set to decrease as the slip amount S increases, as shown in FIG. At the same time, the speed ratio e is set to decrease as the speed ratio e increases.

[0035] Then, ECU 70 is in the step S6 is to set the target opening theta ₀ for the sub-throttle valve 14, setting of the target opening theta ₀ is FIG. 6 (a), the
(B), the carried out in accordance with a map which is previously set engine speed N _E and the target charging efficiency C _E0 as a parameter. That is set to the target opening theta ₀ larger value as the engine rotational speed N _E is increased, also resulting in the target opening theta ₀ as the target charging efficiency C _E0 increases also set to increase.

When the setting of the target opening θ ₀ is completed, the ECU
70 After calculating the charging efficiency C _E based on the intake air amount Q and the engine speed N _E taken from the air flow sensor 10 in step S7, the difference between the charging efficiency C _E at step S8 with respect to the target charging efficiency C _E0, That is, it is determined whether or not the charging efficiency deviation δC _E is 0, and when it is determined to be NO, it is determined in step S9 whether or not the charging efficiency deviation δC _E is positive, and when it is determined to be YES, it is determined in step S10. setting the closing speed V _C of the sub-throttle valve 14. The setting of the closing speed V _C is specifically described in FIGS. 7A and 7B.
As shown in, performed according to the map set and the advance speed ratio e charging efficiency deviation .delta.C _E as a parameter, the speed ratio e, as closing speed V _C charging efficiency deviation .delta.C _E increases each is set to a small value Will be.

Then, the ECU 70 executes step S11, and obtains the closing speed V _C determined in step S10 so as to obtain the target opening θ ₀ set in step S6.
Is output to the throttle actuator 13.

On the other hand, when the ECU 70 determines NO in the step S9, the ECU 70 proceeds to a step S12 to select the position P selected from the select sensor 77.
It is determined whether or not the first and second one-way clutches 51 and 52 are in the direct clutch state based on the speed ratio G and the speed. That is, it is determined whether or not the transmission mechanism 30 is in a directly connected state.

When it is determined that the clutch is in the direct clutch state, the process proceeds to step S13, and as shown in FIG. 8, the opening speed V _O is determined according to the normal map set to the predetermined first speed V ₁ irrespective of the speed ratio e. set, also when it is determined that it is not a direct clutch state, proceeds to step S14, as shown in FIG. 9, sets the speed V _O open accordance special map which is previously set a speed ratio e as a parameter. Note that the above special map has a speed ratio e
There has been set to the extremely slow second speed V ₂ than the first velocity V ₁ before and after 1.

Next, the operation of this embodiment will be described.
When slip amount S calculated by U70 is no longer a zero, that is the engine output by the operation of the throttle actuator 13 is being lowered, the speed V _C close enough that when the speed ratio e is large is reduced Therefore, as shown in FIG.
The driving force F on the upstream side of 0 is gradually reduced from the time t ₁ when the traction control is started,
Eventually, it converges to the target driving force F ₀ . This eliminates that most of the automatic transmission 5 the engine speed N _E at the direct clutch state of decreases rapidly, deterioration in running properties will be avoided.

In the non-direct clutch state of the automatic transmission 5, even if the speed ratio e is in the reverse driving range, the opening speed V _O of the sub-throttle valve 14 is reduced near the speed ratio e of 1. from Rukoto, as shown in FIG. 11, the speed ratio e from the time t ₂ when the speed ratio e is lowered to near 1
Is reduced, and the occurrence of torque shock is avoided.

The opening speed of the sub-throttle valve 14 may be reduced only before the speed ratio e exceeds 1 and becomes 1 again.

The present invention can also be applied to a system in which the output of the engine is controlled by controlling the ignition timing and the fuel injection amount.

[0044]

As described above, according to the present invention, the adjustment speed of the engine output is changed in accordance with the speed ratio of the torque converter. As a result, the engine speed rarely drops to the reverse drive range, thereby avoiding deterioration of the traveling performance.

According to the second invention, the operation gain of the throttle valve is changed according to the speed ratio of the torque converter, so that the same effect as that of the first invention can be obtained.

According to the third and fourth aspects of the invention, when the speed ratio is 1 or less, the operating gain of the throttle adjusting means decreases as the speed ratio increases. A similar effect can be obtained.

According to the fourth aspect of the invention, when the power transmission state in which the one-way clutch provided in the transmission mechanism of the automatic transmission is involved, the speed ratio of the torque converter shifts from a state of 1 or more to a state of 1 or less. When this happens, the operating gain of the throttle adjusting means will be reduced, so even if the engine speed is reduced too much to the reverse drive range, the engine speed is restored and torque transmission is resumed. Is prevented.

According to the fifth aspect, the operation gain of the throttle adjusting means is changed in accordance with the speed ratio at the time of traction control, so that an excessive decrease in the engine speed is suppressed. It is possible to avoid the deterioration of the traveling performance due to the synergistic effect of the engine brake with the decrease in the driving force due to the traction control.

[0049]

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a basic configuration of the first to fifth inventions.

FIG. 2 is a control system diagram of a power train in the embodiment.

FIG. 3 is a skeleton diagram of the automatic transmission.

FIG. 4 is a flowchart illustrating engine output control in the embodiment.

FIG. 5 is an explanatory diagram of a map used for setting a target filling efficiency.

FIG. 6 is an explanatory diagram of a map used for setting a target opening.

FIG. 7 is an explanatory diagram of a map used for setting a closing speed.

FIG. 8 is an explanatory diagram of a normal map used for setting an opening speed in a direct clutch state.

FIG. 9 is an explanatory diagram of a normal map used for setting an opening speed in a non-direct clutch state.

FIG. 10 is a time chart showing an operation immediately after the engine output is reduced.

FIG. 11 is a time chart showing an operation when the speed ratio exceeds 1.

FIG. 12 is a time chart showing a conventional problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle 2, 3 Front wheel 4 Engine 5 Automatic transmission 13 Throttle actuator 14 Subthrottle valve 20 Torque converter 30 Transmission mechanism 51 First one-way clutch 52 Second one-way clutch 70 ECU

Claims (5)

(57) [Claims] 1. An engine control device for a vehicle including an automatic transmission for transmitting an engine output input to a transmission mechanism via a torque converter to driving wheels, and having an engine output adjusting means for adjusting the engine output. A speed ratio calculating means for calculating a speed ratio of the torque converter in the automatic transmission; and an output adjusting speed for changing an output adjusting speed by the engine output adjusting means according to the speed ratio calculated by the calculating means. A control device for an engine, comprising: a change unit. 2. An engine control device for a vehicle including an automatic transmission for transmitting an engine output input to a transmission mechanism via a torque converter to driving wheels, and having an engine output adjusting means for adjusting the engine output. A speed ratio for calculating a speed ratio of a torque converter in the automatic transmission, wherein the engine output adjusting means is a throttle adjusting means for adjusting an opening degree of a throttle valve provided in an intake passage of the engine. Calculating means;
An engine control device, comprising: an operating gain changing unit that changes an operating gain of the throttle adjusting unit according to the speed ratio calculated by the calculating unit. 3. An engine control device for a vehicle including an automatic transmission that transmits an engine output input to a transmission mechanism via a torque converter to driving wheels, and provided with engine output adjusting means for adjusting the engine output. A speed ratio for calculating a speed ratio of a torque converter in the automatic transmission, wherein the engine output adjusting means is a throttle adjusting means for adjusting an opening degree of a throttle valve provided in an intake passage of the engine. Calculating means;
An engine control means for providing an operating gain changing means for reducing the operating gain of the throttle adjusting means as the speed ratio is larger when the speed ratio calculated by the calculating means is 1 or less. apparatus. 4. An engine control apparatus for a vehicle including an automatic transmission for transmitting an engine output input to a transmission mechanism via a torque converter to driving wheels, and having an engine output adjusting means for adjusting the engine output. A speed ratio for calculating a speed ratio of a torque converter in the automatic transmission, wherein the engine output adjusting means is a throttle adjusting means for adjusting an opening degree of a throttle valve provided in an intake passage of the engine. Calculating means;
When the speed ratio calculated by the calculation unit is 1 or less, an operation gain changing unit that decreases an operation gain of the throttle adjustment unit as the speed ratio increases, and an engine provided in a transmission mechanism of the automatic transmission. When the speed ratio calculated by the calculation means shifts from a state of 1 or more to a state of 1 or less in a power transmission state involving a one-way clutch that transmits output in one direction to drive wheels, the throttle adjustment is performed. An engine control device, further comprising: an operation gain lowering means for reducing an operation gain of the means. 5. An engine control device for a vehicle including an automatic transmission for transmitting an engine output input to a transmission mechanism via a torque converter to drive wheels, and having an engine output adjusting means for adjusting the engine output. Wherein the engine output adjusting means is a throttle adjusting means for adjusting an opening degree of a throttle valve provided in an intake passage of the engine, and a slip detecting means for detecting a slip state of a driving wheel; Traction control means for operating the throttle adjusting means so as to suppress a slip state when the vehicle is slipping, speed ratio calculating means for calculating a speed ratio of a torque converter in the automatic transmission, and when the traction control means is operated, The operation gain of the throttle adjusting means is determined according to the speed ratio calculated by the speed ratio calculating means. And an operating gain changing means for changing the engine speed.