JP2895867B2 - Control device for automatic transmission and engine - Google Patents

Description

The present invention relates to a power plant for a vehicle, and more particularly, to an automatic transmission in a power plant including an automatic transmission whose line pressure can be controlled and an engine whose output can be adjusted. The present invention relates to an engine control device.

(Prior Art) Generally, an automatic transmission that constitutes this type of vehicle power plant includes a torque converter to which an engine output is input, and a transmission gear mechanism driven by the output of the torque converter. The power transmission path of the speed change gear mechanism is switched by the selective operation of the plurality of frictional engagement elements, so that the speed is optimally set to the most suitable speed for the operating state. The engagement and release operations of the friction engagement elements in the transmission gear mechanism are performed by controlling the supply and discharge of hydraulic oil to and from the actuators of the engagement elements.

In this case, the torque transmission capacity in the automatic transmission depends on the fastening force of the selected friction fastening element, and the fastening force depends on the pressure of the hydraulic oil supplied to the actuator of the friction fastening element, that is, the line pressure. .

Here, if the line pressure at the time of shifting is too high compared to the input torque from the engine side, the frictional engagement element will be engaged too quickly and a shift shock will occur. Conversely, if the line pressure is too low compared to the input torque, it will take a long time to complete the fastening, and the components of the friction fastening element will be excessively worn or generate heat, which will cause problems in terms of durability. is there. Therefore, in an automatic transmission, it is customary to perform line pressure control such that a torque transmission capacity corresponding to the output torque of the engine is obtained.

In this type of vehicle power plant, in order to reduce the shock generated in the automatic transmission at the time of shifting, for example, as disclosed in Japanese Patent Publication No. 63-14171, the engine output is reduced during shifting. By doing
There is an idea to harmonize the engine output with the torque transmission capability of the automatic transmission.

(Problems to be Solved by the Invention) As described above, as a method of controlling the line pressure in the automatic transmission, there is a method of performing duty control of a solenoid valve for controlling a line pressure using a throttle opening as a representative characteristic of an engine output. . In this control method, the duty of the solenoid valve for line pressure control is stopped because the temperature of the hydraulic oil is low and the control characteristics are unstable during a cold period.
In this case, the line pressure control solenoid valve is fixed in a state where the duty ratio is 0% or 100%, and therefore, the line pressure becomes, for example, the maximum value. Also, when a sensor or the like for detecting the throttle opening breaks down, the duty control is stopped in consideration of safety.

If the speed change operation is performed in a state in which the line pressure corresponding to the engine output cannot be obtained, the frictional engagement element of the transmission gear mechanism in the automatic transmission is excessively fastened, causing a speed change shock or conversely. It takes a long time to complete and there are still issues to be improved.

Note that the technique described in the above publication does not take into consideration the control of the line pressure, and therefore cannot cope with a gear shift in a state where the line pressure is set to the maximum value.

In view of the above-described problems in a power plant in which an automatic transmission capable of controlling line pressure and an engine whose output is adjustable are combined, the present invention provides a state in which the line pressure is set to a maximum value at a low temperature or a failure. It is an object of the present invention to achieve both the suppression of a shock at the time of shifting and the reduction of the shifting time.

(Means for Solving the Problems) In order to solve the above problems, the present invention is characterized by using the following means.

First, an invention according to claim 1 of the present application (hereinafter referred to as a first invention) is a vehicle power plant in which an automatic transmission capable of controlling line pressure and an engine whose output is adjustable are combined. Line pressure control means for setting the line pressure to a maximum value when the state is detected; and Engine output adjusting means for increasing the output of the engine as compared with a non-shift operation.

The invention according to claim 2 (hereinafter, referred to as a second invention)
Is characterized in that the predetermined state in the first invention is when the temperature of the hydraulic oil is low.

The invention according to claim 3 (hereinafter, referred to as a third invention) is characterized in that the predetermined state in the first invention is when the line pressure setting means has failed.

(Operation) According to the above configuration, a predetermined state in the power plant, for example, when the temperature of the hydraulic oil specified in the second invention is low, or in the line pressure setting means such as the throttle opening sensor specified in the third invention. In the event of a failure or the like, even if a shift operation is performed in the automatic transmission when the line pressure is set to the maximum value by the line pressure control unit, the engine output adjusting unit may adjust the engine output to correspond to the set line pressure. Will be raised. As a result, the engine output and the torque transmission capacity of the automatic transmission are appropriately harmonized, and the shift operation is performed in a short time without generating excessive shift shock.

(Examples) Hereinafter, examples of the present invention will be described.

As shown in FIG. 1, an engine 2 constituting a power plant 1 according to this embodiment has four cylinders 3... 3 arranged in series along a cylinder bank, and these cylinders 3. , An ignition system for igniting and burning the mixture supplied to each of the cylinders 3,..., And discharging the exhaust gas after combustion to each of the cylinders 3,.
And an exhaust passage 5 that collects and discharges the exhaust gas. The intake passage 4 is provided with a throttle valve 6 interlocked with an accelerator pedal (not shown).

Here, the ignition system will be described. The ignition system includes an ignition plug 7... 7 attached to each cylinder 3.
A high-voltage secondary pulse generated by the ignition coil unit 9 is distributed and supplied to each of the ignition plugs 7... 7 via a distributor 8. The generation timing of the high-voltage secondary pulse is controlled by the ignition control unit 10.

On the other hand, the automatic transmission 11 constituting the power plant 1 together with the engine 2 includes a torque converter (not shown) to which an engine output is input, and a hydraulically operated transmission gear mechanism (not shown) driven by the output of the torque converter. (Not shown), and is provided with a hydraulic circuit section 12 for generating a hydraulic pressure used for controlling these operations. Then, the engine output output from the automatic transmission 11 is transmitted to the drive wheels 15, 15 via the differential device 13 and the axles 14, 14.
Is transmitted to

The power plant 1 according to the present embodiment includes a transmission control unit that controls the operation of the automatic transmission 11.
An engine control unit 17 for controlling operation of the engine 2 is provided.

First, the transmission control unit 16 includes a water temperature signal from a water temperature sensor 18 attached to the engine block, a throttle opening signal from a throttle opening sensor 19 for detecting the opening of the throttle valve 6, and an automatic transmission. An oil temperature signal from an oil temperature sensor 20 that detects the temperature of the hydraulic oil in 11, a rotation speed on the output side of the torque converter, that is, a turbine rotation speed signal from a turbine rotation speed sensor 21 that detects a turbine rotation speed, A vehicle speed signal from a vehicle speed sensor 22 that detects the vehicle speed of the vehicle is input. And this transmission control unit 16
According to the throttle opening and the vehicle speed detected by the sensors 19 and 22, the speed of the automatic transmission 11 is set to the optimum speed according to the driving state, and the hydraulic pressure is set so as to be the set speed. A shift control signal is output to the shift solenoid valves 23, 24, 25 of the circuit section 12, and a shift information signal indicating the current shift stage is output to the engine control unit 17. Further, the transmission control unit 16 outputs a lock-up control signal to the lock-up solenoid valve 26 of the hydraulic circuit unit 12 in accordance with the throttle opening and the vehicle speed, so that the torque converter is operated in accordance with the operation state. Lock up and release the lockup state.

Here, the hydraulic circuit unit 12 is provided with a line pressure control solenoid valve 27 used for controlling the line pressure in the automatic transmission 11, and the line pressure control solenoid valve 27 is connected to the transmission control unit 16 The line pressure is adjusted in accordance with the duty ratio D of the line pressure control signal output from the controller. In this case, when a line pressure control signal having a duty ratio D of 0% is input, the line pressure is set to the maximum value, and when a line pressure control signal having a duty ratio D of 100% is input, the line pressure becomes minimum. It is set to a value.

On the other hand, the engine control unit 17 includes an engine speed signal from an engine speed sensor 28 provided in the distributor 8, a crank angle signal from a crank angle sensor 29 also provided in the distributor 8, and the water temperature sensor 18 , A throttle opening signal from the throttle opening sensor 19, and an intake pressure signal from an intake pressure sensor 30 disposed in the intake passage 4 downstream of the throttle valve 6. You. In the engine control unit 17, the sensor 3
The basic ignition timing is set based on the intake negative pressure detected by 0, 28 and the engine speed, and a correction such as a water temperature correction based on a water temperature value of the value detected by the water temperature sensor 18 is added. The final ignition timing is set. Then, based on the crank angle detected by the crank angle sensor 29, an ignition timing control signal is output to the ignition control unit 10 so as to ignite at the final ignition timing.

Next, the operation of the present embodiment will be described with reference to FIGS.

Transmission control unit 16 and engine control unit 17
Performs control in accordance with the flowchart of FIG. 2 when the engine 2 is operating.

That is, first the various signals from the sensors shown in FIG. 1 in step S ₁ is entered, then a predetermined failure determination process in step S ₂ is performed. In this fail determination process, it is determined whether or not the throttle opening sensor 19 has a failure, and when the sensor 19 has failed, the failure flag _FF is set to “1”.

The determination and the failure flag F _F is performed is determined whether "1" in the step S _3, when the flag F _F is not "1", that is, the throttle opening sensor 19 does not fail when it is a predetermined cold determination process is performed in step S _4. In this determination process, the oil temperature sensor
The oil temperature of the hydraulic oil detected by 20, for example, cold judgment temperature T ₀ (for example, -15 ° C.) cold flag F _C is representative of a cold state when: is set to "1", the oil temperature When the temperature exceeds the cold judgment temperature T ₀ , the above cold flag
F _C is cleared to "0".

When cold determination process ends, the cold flag F _C is performed is determined whether "1" in the step S _5, when the flag F _C is set to "1", the throttle opening in Step S ₅ degrees theta is made a determination whether or not a predetermined switching換開degree theta ₀ or more, with the line pressure control duty ratio D at step S ₇ is set to 0% when larger, the duty ratio D at step S ₈ Is output from the transmission control unit 16 to the line pressure control solenoid valve 27 in the hydraulic circuit section 12. In contrast, the throttle opening theta is when it is not the switching換開degree theta ₀ or more, the duty ratio D is set to 100% in step S _9.

Then, the following step S ₁₀ in the shift flag F _S is "1" whether the determination is made. The shift flag F _S is set to “1” at the time of shifting, and is cleared to “0” after the end of shifting.

When the shift flag F _S is determined to be "1" in step S _10, namely at the time of transmission, the step S ₁₁
In the torque control ratio Tc is set on the basis of the type S _X of the throttle opening θ and the shift to the map as parameters. For example the first speed map that is used during shifting to the second speed, as shown in FIG. 3, the torque control rate Tc when the throttle opening theta is less than the switching換開degree theta ₀
A value less than 100%, the throttle opening theta is set such that the switching換開degree theta ₀ or more becomes the torque control ratio Tc is a value exceeding 100%. Then, the ignition timing in accordance with the torque control ratio Tc based on the map shown in Figure 4 in step S ₁₂ is set, the ignition spark timing control signal to be ignited at the ignition timing from the engine control unit 17 Output to the control unit 10.

In this case, the line pressure in the automatic transmission 11 becomes the minimum value when the throttle opening θ is smaller than the switching opening θ ₀ , as shown by arrows a and b in FIG. In the above state, the maximum value is set.

In contrast, the torque control rate Tc which is set in the step S _11, from the map shown in FIG. 3 as described above, value less than 100% when the throttle opening theta is less than switching換開degree theta ₀ Is more than 200
Set to a value exceeding%. Then, when the ignition timing control in step S ₁₂ is a map of FIG. 4,
When the torque control ratio Tc is smaller than 100%, the ignition timing is set to the retard side, and when it exceeds 100%, the ignition timing is set to the advanced side. Therefore, the engine torque, when the throttle opening theta is less than switching換開degree theta ₀ is decreased so as to correspond to the set line pressure as shown by an arrow c of FIG. 5 (a) (minimum value), the throttle opening When the degree θ exceeds the switching opening degree θ ₀ , as shown by an arrow D, it rises so as to correspond to the set line pressure (maximum value). Thereby, the torque transmission capacity in the automatic transmission 11 obtained from the engine output and the line pressure is appropriately harmonized, and the shift operation is performed in a short time without generating excessive shift shock.

On the other hand, when it is determined not to be cold flag F _C is set to "1" in step S _5, the shift flag F _S moves to step S ₁₃ is performed is determined whether "1", the flag
F value of _S is not "1", i.e. when it is determined not to be the time shift, the duty ratio D of the line pressure control of the throttle opening θ and the turbine speed N _T as a parameter is set in step S ₁₄ , so that the line pressure control signal corresponding to the duty ratio D is set at step S ₁₅ is output to the line pressure control solenoid valve 27 in the hydraulic circuit portion 12. In contrast, when the value of the transmission flag F _S is determined to be "1" in the step S _13, namely the line pressure control of the type S _X of the throttle opening θ and the transmission as parameters in step S ₁₆ at the time of shift set the duty ratio D is likewise line pressure control signal corresponding to the duty ratio D is set at step S ₁₅ is output to the line pressure control solenoid valve 27 in the hydraulic circuit portion 12.

Further, when the value of the failure flag F _F in step S ₃ is determined as "1", i.e., a throttle opening sensor
When 19 is determined to be faulty, step S ₄ ~
Line pressure control duty ratio D at step S ₇ skipping S ₆ is set to 0%, the line pressure control signal line pressure control in the hydraulic circuit portion 12 corresponding to the duty ratio D is set at step S ₈ Is output to the solenoid valve 27 for use. Incidentally, in this case, as the map used in step S _11, as shown in FIG. 6, which torque control ratio Tc of 100% over the entire range of the throttle opening θ is used.

By the way, the line pressure when the throttle opening sensor 19 fails as described above is set to the maximum value as shown by the arrow f in FIG. 7 (b).

In contrast, the torque control rate Tc which is set in the step S _11, from the map shown in FIG. 6, is set to a larger value as the throttle opening θ is small. Then, when the ignition timing control in step S _12, the map of FIG. 4, the ignition timing is to be set in advance side. Therefore, the engine torque is
As shown by the arrow in FIG. 9A, the pressure rises so as to correspond to the set line pressure (maximum value). As a result, the shift shock is reduced.

In the present embodiment, the torque control of the engine is performed by controlling the ignition timing. However, the intake air amount or the fuel supply amount may be controlled.

(Effects of the Invention) As described above, according to the present invention, even when a shift operation is performed in the automatic transmission when the line pressure is set to the maximum value in a cold state or a failure state, the output of the engine Is increased to correspond to the set line pressure, so that the engine output and the torque transmission capacity of the automatic transmission are appropriately harmonized, and the shift operation can be performed in a short time without generating excessive shift shock. Will be

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a system diagram showing a power plant and a control system thereof according to the present invention, and FIG. 2 is an operation executed by a transmission control unit and an engine control unit in the system. FIGS. 3 and 4 are flow charts showing control, FIGS. 3 and 4 are explanatory diagrams of maps used for the control, and FIG.
FIG. 6 is an explanatory diagram of another map used for control at the time of failure determination, and FIG. 7 is an explanatory diagram of an operation by control using the map. 2 ... engine, 11 ... automatic transmission, 16 ... line pressure control means (transmission control unit), 17 ... engine output adjustment means (engine control unit), 19 ... line pressure setting means (throttle opening Degree sensor).

Continuation of the front page (56) References JP-A-61-119435 (JP, A) JP-A-54-1759 (JP, A) JP-A-1-120471 (JP, A) JP-A-61-157856 (JP, A) JP-A-64-95943 (JP, A) JP-A-62-164060 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60K 41/00-41/28 F02D 29/00-29/06 F16H 59/00-63/48

Claims (3)

(57) [Claims] 1. A vehicle power plant in which an automatic transmission capable of controlling a line pressure and an engine whose output can be adjusted are combined. When a predetermined state in the power plant is detected, the line pressure is raised to a maximum value. A line pressure control means to be set, and an engine output adjustment for increasing the output of the engine to correspond to the set line pressure at the time of shifting with the line pressure set to the maximum value by the control means, as compared with the non-shifting state. And a control device for an automatic transmission and an engine in a vehicle power plant. 2. The control apparatus for an automatic transmission and an engine in a power plant for a vehicle according to claim 1, wherein the predetermined state is a time when the operating oil is at a low temperature. 3. The control apparatus for an automatic transmission and an engine in a power plant for a vehicle according to claim 1, wherein said predetermined state is a time when said line pressure setting means is out of order.