JPH0815854B2 - Operation control method for internal combustion engine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation control method for an internal combustion engine used in a vehicle such as an automobile, and particularly to anticreep control (creep reduction control) by reducing the engagement pressure of a forward clutch. The present invention relates to an operation control method of an internal combustion engine used in combination with an automatic transmission for a vehicle.

2. Description of the Related Art Automatic transmissions used in vehicles such as automobiles are generally
A fluid type torque converter which receives rotational power from a prime mover such as an internal combustion engine, and a plurality of friction engagement devices which receive rotational power from the fluid torque converter and switch between a plurality of gear stages by engaging and disengaging the friction engagement devices. A planetary gear type gear transmission is provided, and the gear transmission is configured to be able to switch the gear according to a predetermined shift pattern according to the vehicle speed and the depression amount of the accelerator pedal.

Generally, in the conventional automatic transmission for vehicles as described above,
When the manual shift range is set to a driving range such as the D range, the gear transmission is in a neutral state even when the accelerator pedal is released and the vehicle speed is substantially zero, that is, even during idle operation. Not
It is set to the first speed, and therefore the vehicle is started with excellent responsiveness to the depression of the accelerator pedal, but when the gear transmission is set to the first speed during idle operation, Since the output of the internal combustion engine is transmitted to the forward travel input member of the gear transmission through the fluid torque converter, the idle vibration is large and creep is generated to stop the vehicle completely. The brake pedal must be depressed relatively strongly to operate the brake, and the drag of the hydraulic torque converter at this time deteriorates the fuel economy during idle operation. Is known to increase in temperature.

In view of the above-mentioned problems, the friction of the gear transmission is set so that the gear transmission is in the neutral state or equivalent to the neutral state during the idle operation in which the manual shift range is set to the forward traveling range and the vehicle is substantially stopped. Of the engagement devices, the so-called forward clutch that selectively connects the output member of the fluid torque converter and the vehicle forward travel input member of the gear transmission is released or the engagement pressure of the forward clutch is set lower than when the forward speed stage is achieved. Set the forward clutch to a value that causes slippage,
An automatic transmission for a vehicle equipped with an anti-creep control device for preventing the output torque of a fluid torque converter from being transmitted to an input member for forward traveling of a gear transmission has already been proposed. -19962, JP-A-56-21047, JP-A-58-128552, JP-A-58-19395
No. 3 and JP-A No. 59-6454.

The automatic transmission for vehicles as described above achieves the intended purpose,
In this vehicle automatic transmission, idle vibration is reduced, the occurrence of creep is prevented, the vehicle is completely stopped even if the brake pedal is not strongly depressed, and the fluid torque converter Elimination of drag improves fuel economy during idle operation and also avoids increasing temperature of hydraulic fluid in the hydraulic torque converter.

Problems to be Solved by the Invention However, when the anticreep control as described above is released when the vehicle starts, an increase in the engine output due to the depression of the accelerator pedal occurs while the engagement pressure of the forward clutch increases. The torque acting on the forward clutch increases, which increases the amount of energy absorbed by the friction material of the forward clutch when the forward clutch is engaged.Especially, when the accelerator pedal is suddenly greatly depressed and the engine output sharply increases. , The durability of the forward clutch is reduced. Further, in this case, the fluctuation of the output shaft torque becomes large, and the manual shift range change shock from the neutral range to the forward drive range becomes large.

In view of the above-mentioned problems, the present invention prevents the deterioration of the durability of the forward clutch and a large shock when the anti-creep control is performed by reducing the engagement pressure of the forward clutch when the anti-creep control is released. It is an object of the present invention to provide a method for controlling the operation of an internal combustion engine.

Means for Solving the Problems According to the present invention, the object as described above is characterized in that the engine output is temporarily reduced when the engine output is equal to or more than a predetermined value when the anti-creep control is released. It is achieved by the operation control method.

The output of the internal combustion engine when the anti-creep control is released may be temporarily reduced by retarding the ignition timing of the internal combustion engine, reducing the amount of fuel supplied to the internal combustion engine, or reducing the amount of intake air.

The time for reducing the engine output may be variably set according to the engine load when the anti-creep control is released.

The timing for canceling the reduction of the engine output may be determined according to the rotational speed of the rotating member of the automatic transmission for a vehicle or the hydraulic pressure of the forward clutch.

According to the operation control method of the internal combustion engine according to the present invention, the engine output is reduced when the anti-creep control is released, that is, during the engagement process of the forward clutch, so that the forward clutch is engaged. The amount of energy absorbed by the friction material of the forward clutch can be reduced, and deterioration of the durability of the forward clutch can be avoided. Further, along with this, it is possible to prevent the output shaft torque from fluctuating greatly, and it is possible to prevent a large shock from occurring when the manual shift range is changed from the neutral range to the forward drive range.

When the forward clutch is engaged, the amount of energy absorbed by the friction material of the forward clutch increases as the durability of the forward clutch decreases, when the engine load is equal to or higher than a predetermined value. Therefore, it is only when the engine load is above a predetermined value that the engine output needs to be temporarily reduced when the anti-creep control is released. Therefore, because the engine output is reduced only when the engine load is above a predetermined value, the intended purpose is achieved, and when the engine load is relatively small, in addition to that, the engine load is reduced. It is possible to prevent the drivability of the internal combustion engine from being deteriorated.

The period during which engine output is reduced when anti-creep control is canceled is preferably as short as possible after achieving the intended purpose from the viewpoint of the acceleration response of the internal combustion engine. The period of time to be set is variably set according to the engine load when the anti-creep control is released, and the timing of releasing the reduction of the engine output should be synchronized with the completion of the engagement of the forward clutch. It is set according to the number of revolutions or the oil pressure of the forward clutch.

Example Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 schematically shows the structure of a general automatic transmission for a vehicle. The automatic transmission 1 includes a three-element one-stage two-phase general hydraulic clutch-equipped direct torque clutch 2 having a pump impeller 3, a turbine impeller 4, a stator impeller 5, and a direct coupling clutch 6, and an auxiliary transmission device. A pump impeller 3 which is an input member of the fluid torque converter 3 and is connected to an output shaft 101 of the internal combustion engine 100, and a turbine blade which is an output member of the fluid torque converter 2. The vehicle 4 is drivingly connected to an input shaft 9 of a gear transmission 7, and an output shaft 8 of the gear transmission 7 is drivingly connected to a drive wheel (not shown) of the vehicle via a differential gear unit.

The internal combustion engine 100 is configured such that fuel is injected and supplied from a fuel injector 102, the ignition timing is controlled by an ignition timing control device 103, and the motion as a combustion engine is controlled.

The operation of the fuel injector 102 and the ignition timing control device 103 is controlled by the engine control computer 70. Engine control computer
An engine control sensor group 71 including an intake pipe pressure sensor, an engine speed sensor, a water temperature sensor and the like inputs various information required for engine operation control from a transmission control computer 60, and a fuel injection amount and an ignition timing according to the information. Is determined and a control signal for this is output to each of the fuel injector 102 and the ignition timing control device 103.

The gear transmission 7 is a sub gear transmission 10 and a main gear transmission.
11 and 11 in series with each other.

The sub-gear transmission 10 rotates a sun gear 12, a ring gear 13 concentric with the sun gear 12, a planetary pinion 14 between the sun gear 12 and the ring gear 13 and meshed with the sun gear 12, and a planetary pinion 14. Carrier 15 supported as possible, one-way clutch (F ₀ ) 16 that blocks the left rotation of carrier 15 with respect to sun gear 12, and OD clutch (C ₀ ) 17 that selectively connects sun gear 12 and carrier 15
And an OD brake (B ₀ ) 18 for selectively fixing the sun gear 12 to the transmission case, the carrier 15 is drivingly connected to the input shaft 9, and the OD clutch 17 and the OD brake 18 are selectively connected. It is adapted to be switched between two shift speeds by engagement.

The main gear transmission 11 includes a front sun gear 20 and a rear sun gear 21 that are connected to each other by an intermediate shaft 19, and a front ring gear 22 that is provided concentrically with the front sun gear 20.
And a rear ring gear provided concentrically with the rear sun gear 21
23, a front planetary pinion 24 between the front sun gear 20 and the front ring gear 22 and meshing with them, a rear planetary pinion 25 between the rear sun gear 21 and the rear ring gear 23 and meshing with both, and a front planetary gear. A front carrier 26 that rotatably supports a pinion 24, a rear carrier 27 that rotatably supports a rear planetary pinion 25, a front ring gear 22 that is an input member for forward traveling of the main gear transmission 11, and a sub gear transmission. Forward clutch (C ₁ ) 28 that selectively connects to the ring gear 13 that is the output member of 10 in a torque transmission relationship
And a direct clutch (C ₂ ) 29 for selectively connecting the intermediate shaft 19 and the ring gear 13 in a torque transmission relationship, and the intermediate shaft 19
Shift brake (B ₁ ) 30 that selectively locks the rear carrier 27 to the transmission case, another shift brake (B ₂ ) 31 that selectively locks the rear carrier 27 to the transmission case, and the rear carrier 27 And a one-way clutch (F ₁ ) 32 for locking the rotation of the front carrier 26 and the rear ring gear 23 are drivingly connected to the output shaft 8, and the plurality of clutches and the plurality of brakes are respectively provided. By engaging and disengaging in a predetermined combination, the gears can be switched between a plurality of shift stages of three forward gears and one reverse gear.

The gear transmission 7 is a sub gear transmission 10 and a main gear transmission.
A plurality of eleven clutches and a plurality of brakes are engaged and disengaged according to the table shown below to include an overdrive stage by the cooperation of the auxiliary gear transmission 10 and the main gear transmission 11. A plurality of shift speeds, five forward speeds and one reverse speed, are selectively achieved.

In this table, a circle indicates that the clutch or brake is engaged, a cross indicates that the clutch or brake is released, and a triangle indicates that the one-way clutch is on the internal combustion engine side. It is shown that it is engaged (locked) when the engine is driven to drive the drive wheels, and released (free) when the engine is braked when the internal combustion engine is driven from the drive wheel side.

In the L range, the upshift to the second speed is not performed, and only the downshift from the second speed to the first speed is performed.

The sub gear transmission 10 and the clutch 17 of the main gear transmission 11,
28, 29 and brakes 18, 30, 31 are hydraulically actuated ones that are driven by a hydraulic servo device and selectively engage and operate, and a hydraulic control device that controls the supply and discharge of hydraulic pressure to and from the hydraulic servo device. A general shift known per se which is predetermined according to the vehicle speed and the throttle opening for each manual shift range under the control of an electronic control device including a microcomputer for instructing switching of the oil passage of the hydraulic control device. By engaging and disengaging the clutch and the brake in accordance with the pattern in the above-described combination, the gear stage of the gear transmission 7 is switched and set.

FIG. 2 shows an essential part of one embodiment of an automatic transmission for a vehicle according to the present invention. The hydraulic control device for shift control has an idle control valve 36 which is switched by a solenoid 37, and the port a of the idle control valve is used.
Is an oil passage 38a and an oil passage 38 having a throttle 47a on the way,
The other port b is connected to the forward port of the manual shift valve 39 by an oil passage 38b and an oil passage 38 each having a throttle 47b in the middle, and these ports are forwarded in the manual shift range such as D range, S range and L range. When the travel range is set, the line oil pressure is always supplied from the manual shift valve 39. still,
The manual shift valve 39 is connected to a line hydraulic control valve (primary regulator valve) 41 by an oil passage 40, and the line hydraulic control valve 41 is connected to an oil pump 43 by an oil passage 42.

The idle control valve 36 has two ports e and f in addition to the ports a and b, and the port e is the oil passage 44 and the throttle port.
It is connected to a relief valve 46 equipped with 45, and port f has an oil passage 48.
Is connected to the oil chamber 35b of the hydraulic servo device 33 of the forward clutch 28. When the solenoid device 37 is energized, the idle control valve 36 connects the port a to the port e as shown and simultaneously connects the port e and the port f, while the solenoid device 37 is energized. When not performed, the port f is disconnected from the port e and is connected to the port b.

Therefore, when the solenoid 37 of the idle control valve 36 is energized when the manual shift range is in the forward drive range such as the D range, the hydraulic pressure lower than the line hydraulic pressure and determined by the relief set pressure of the relief valve 46 is applied to the forward clutch 28. Is supplied to the oil chamber 35b, and line hydraulic pressure is supplied to the oil chamber 35b when the solenoid 37 is not energized.

The hydraulic servo device 33 of the forward clutch 28 includes the servo piston 35a, and the servo piston 35a moves to the right in the figure against the spring force of the return spring 34 in response to an increase in the hydraulic pressure supplied to the oil chamber 35b. By forward clutch 28
Is engaged to increase the clutch engagement pressure in accordance with the increase in the oil pressure in the oil chamber 35b.

The relief set pressure of the relief valve 46 is set to a hydraulic pressure equal to the servo hydraulic pressure just before the forward clutch 28 starts slipping due to slippage of the forward clutch 28, and therefore the oil chamber 35b of the forward clutch 28 is set. When the hydraulic pressure equal to the relief set pressure of the relief valve 46 is being supplied to the forward clutch 28, the forward clutch 28 is set to a state where slippage may occur just before starting the torque transmission. As a result, anti-creep control is performed. When the line oil pressure is supplied to the oil chamber 35b of the forward clutch 28, the forward clutch 28 is completely engaged, and the ring gear 13 of the auxiliary gear transmission 10 and the main gear transmission are shifted without slippage. The front ring gear 22 of the device 11 is connected in a perfect torque transmitting relationship.

The energization control of the solenoid 37 of the idle control valve 36 is performed by the transmission control computer 60. The transmission control computer 60 includes a general microcomputer.
Information about 100 throttle valve openings is displayed by the vehicle speed sensor 6
Shift position switch 6
The information about the manual shift range is given from 4 and the information about whether the foot brake or the parking brake of the vehicle is braking is given from the brake switch 65, respectively, and the solenoid 37 is energized according to the flow chart shown in FIG. To control the anti-creep.

Next, with reference to the flow chart shown in FIG. 3, a description will be given of an anti-creep control and a procedure for implementing the operation control method of the internal combustion engine according to the present invention. The routine of the flowchart shown in FIG. 3 is repeatedly executed every predetermined time or every predetermined crank angle.

In step 100, information is input from various sensors.

In step 101, the timer set value T ₁ and another timer set value T ₂ are determined according to the throttle opening. The timer set values T ₁ and T ₂ are determined so as to increase as the throttle opening increases.

At step 102, it is judged if the flag F is 2. When F = 2, it means that the engine output reduction at the time of canceling the anti-creep control has already been executed, and at this time, the routine proceeds to step 121, while when F = 2, the routine proceeds to step 103.

In step 103, the manual shift range is D
It is determined whether the vehicle is in the forward traveling range such as the range, the S range or the L range. If the manual shift range is the forward drive range, proceed to step 106,
On the other hand, when the manual shift range is not the forward drive range, that is, when it is the P range, R range, or N range, the routine proceeds to step 104.

At step 104, it is judged if the flag F is 0 or not. When F = 0, it is a normal time when neither anti-creep control nor engine output reduction control is being performed, and at this time it is reset. When F = 0 is not satisfied, the routine proceeds to step 105.

In step 105, the energization of the solenoid 37 of the idle control valve 36 is stopped and the flag F is set to zero. This releases the anti-creep control.

In step 106, based on the throttle opening detected by the throttle opening sensor 62, it is determined whether or not the throttle valve 100 of the internal combustion engine is fully opened, that is, in the idle opening position. When the throttle valve is in the idle opening position, the process proceeds to step 107, while when the throttle valve is not in the idle opening position, the process proceeds to step 111.

At step 107, it is judged if the vehicle speed is equal to or lower than a predetermined value close to zero. When the vehicle speed is below the predetermined value, the routine proceeds to step 108, and when the vehicle speed is not below the predetermined value, the routine proceeds to step 111.

In step 108, it is determined whether or not the vehicle is being braked, that is, whether or not at least one of the foot brake and the parking brake is operating. When the vehicle is braking, proceed to step 109,
On the other hand, when the vehicle is not being braked, the routine proceeds to step 111.

In step 109, it is determined whether the flag F is 1. When F = 1, the anti-creep control has already been executed and is reset at this time. On the other hand, when F = 1, the routine proceeds to step 110.

In step 110, the energization of the solenoid 37 of the idle control valve 36 is started and the flag F is set to 1. As a result, a predetermined hydraulic pressure that is lower than the line hydraulic pressure determined by the relief valve 46 is supplied to the oil chamber 35b of the forward clutch 28, and the engagement pressure of the forward clutch 28 is lower than when the forward shift stage is achieved, and the value that causes the forward clutch 28 to slip Is set to.

At this time, the forward clutch 28 slips to prevent the output torque of the fluid type torque converter 2 from being transmitted to the front ring gear 22 which is an input member for forward traveling of the gear transmission 7. This causes idle vibration. Is reduced and the occurrence of creep is prevented.

At step 111, it is judged if the flag F is 0 or not. When F = 0, it means that the anti-creep control is not being performed, and at this time it is reset, while when F = 0, the routine proceeds to step 112.

At step 112, it is judged if the flag F is 3. When F = 3, the process proceeds to step 115, while when F = 3, the process proceeds to step 113.

In step 113, the timer is started. After step 113, the process proceeds to step 114.

In step 114, the energization of the solenoid 37 of the idle control valve 36 is stopped. As a result, the line hydraulic pressure is supplied to the oil chamber 35b of the forward clutch 28, whereby the engagement of the forward clutch 28 is started and the anti-creep control is released.

At step 115, it is judged if the throttle opening Θ is larger than a predetermined value Θset. When Θ> Θset, the routine proceeds to step 116, where Θ> Θ
If it is not set, the process proceeds to step 122.

In step 116, an engine output reduction command is output to the engine control computer 70. Upon receiving the engine output reduction command from the transmission control computer 60, the engine control computer 70 immediately outputs a retard control signal to the ignition timing control device 103 or a fuel injection amount reduction signal to the fuel injector 102. As a result, the output of the internal combustion engine 100 is reduced as compared with the throttle opening at that time. This engine output reduction amount may be a constant value or may be increased according to the maximum throttle opening.

In step 117, the timer value t of the timer at this time
Is stored as the engine output reduction start time T ₀ .

In step 118, the engine output reduction time (t-T ₀ )
Is determined to be greater than the timer set value T ₁ . When t−T ₀ > T ₁ , it means that the engine output has been reduced for a predetermined time determined by the timer set value T ₁ , and at this time, the routine proceeds to step 119, where the predetermined time has not yet elapsed. If not, go to step 120.

In step 119, an engine output cancellation command is output to the engine control computer 70. When the engine control computer 70 receives the engine output cancellation command from the transmission control computer 60, it immediately stops outputting the engine output reduction signal to the fuel injector 102 or the ignition timing control device 103. As a result, the engine output of the internal combustion engine 100 returns to the engine load determined by the throttle opening. Again step
At 119, the flag F is set to 0.

In step 102, the flag F is set to 2.

Step 121 is executed when flag F = 2,
In step 121, it is judged if the throttle opening Θ is larger than a predetermined value Θset. Θ> Θ set
If so, then go to step 181, where Θ> Θset
If not, proceed to step 119. As a result, when the throttle opening becomes less than the predetermined value, that is, when the engine load becomes less than the predetermined value, the engine output is immediately reduced when the anti-creep control is released even if the engine output is not reduced for a predetermined time. The reduction is released.

At step 122, it is judged if the timer value t of the timer is smaller than the timer set value T ₂ . t <T ₂
In other words, when the predetermined value determined by the timer set value T ₂ has not elapsed since the anti-creep control condition was not satisfied, the routine proceeds to step 123, while when the predetermined time has elapsed, the routine proceeds to step 124.

In step 123, the flag F is set to 3. As a result, even if the throttle opening Θ is still less than or equal to the predetermined value Θset immediately after the start of the anti-creep control cancellation, the throttle opening Θ is greater than or equal to the predetermined value Θset during the predetermined time determined by the timer set value T _2. Then, the engine output reduction control as described above is performed.

In step 124, the flag F is set to 0.

In the above-described embodiment, the engine output reduction control that is performed when the anti-creep control is released is time-controlled, but is detected by the engine speed detected by the engine speed sensor 66 and the vehicle speed sensor 63. Based on vehicle speed, or
The drum chamber of the OD clutch 17 detected by the OD clutch drum rotation speed sensor 68 or the oil chamber of the forward clutch 28 detected by the forward clutch oil pressure sensor 67.
It is also possible to find out when the forward clutch 28 is completely engaged based on the hydraulic pressure of 35b, and to decide the release timing of the engine output reduction control based on this. The control in this case is performed according to the flow chart shown in FIG.

If the internal combustion engine 100 has an intake air amount control device 104 in its intake system in addition to the throttle valve interlocked with the accelerator pedal, the intake air amount control device 104 reduces the intake air amount. The engine output may be reduced.

In the above, the present invention has been described in detail with respect to a specific embodiment, but the present invention is not limited to this, and various embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a general automatic transmission for a vehicle,
FIG. 2 is a schematic configuration diagram showing an example of a control device used for carrying out a control method at the time of idling operation of an automatic transmission for a vehicle according to the present invention, and FIGS. It is a flowchart showing. 1 …… Vehicle automatic transmission, 2 …… Fluid torque converter, 3 …… Pump impeller, 4 …… Turbine impeller, 5 …… Stator impeller, 6 …… Direct coupling clutch, 7 …… Gear transmission , 8 ...
Output shaft, 9 Input shaft, 10 Secondary gear transmission, 11 Main gear transmission, 12 Sun gear, 13 Ring gear, 14
… Planetary pinion, 15 …… Carrier, 16 …… One way clutch, 17 …… OD clutch, 18 …… OD brake, 19…
… Intermediate shaft, 20 …… Front sun gear, 21 …… Rear sun gear, 22 …… Front ring gear, 23 …… Rear ring gear, 2
4 …… front planetary pinion, 25 …… rear planetary pinion, 26 …… front carrier, 27 …… rear carrier, 28 …… forward clutch, 29 …… direct clutch, 30, 31 …… shift brake, 32 …… One-way clutch, 33 …… hydraulic servo device, 34 …… Return spring, 35a …… Servo piston, 35b …… Oil chamber, 36 …… Idle control valve, 37…
… Solenoid, 38, 38a, 38b …… Oil passage, 39 …… Manual shift valve, 40 …… Oil passage, 41 …… Line hydraulic control valve, 42 ……
Oil passage, 43 …… Oil pump, 44 …… Oil passage, 45 …… Throttle port, 46 …… Relief valve, 47a, 47b …… Throttle, 48 …… Oil passage, 60
...... Transmission control computers, 62
...... Throttle opening sensor, 63 …… Vehicle speed sensor, 64 …… Shift position switch, 65 …… Brake switch, 66…
… Engine speed sensor, 67 …… Forward clutch oil pressure sensor, 68 …… OD clutch drum speed sensor, 70 …… Engine control computer, 71 …… Engine control sensor group, 100 …… Internal combustion engine, 101 …… Output shaft , 102 ...
… Fuel injector, 103 …… Ignition timing control device, 104 ……
Intake air amount control device

Claims (4)

[Claims] 1. The engagement pressure of the forward clutch is reduced by reducing the hydraulic pressure supplied to the forward clutch during idle operation when the manual shift range is set to the forward drive range and the vehicle is substantially stopped. In the operation control method of an internal combustion engine used in combination with an automatic transmission for a vehicle in which anti-creep control is performed to prevent the occurrence of creep, when the engine load is above a predetermined value when the anti-creep control is released, the engine output is An operation control method for an internal combustion engine, which is characterized by temporarily reducing. 2. The internal combustion engine operation control method according to claim 1, wherein the time for reducing the engine output is variably set according to the engine load when the anti-creep control is released. Engine operation control method. 3. The internal combustion engine operation control method according to claim 1, wherein the timing for releasing the reduction of the engine output is the rotational speed of the rotary member of the vehicle automatic transmission. A method for controlling the operation of an internal combustion engine, which is characterized in that 4. The operation control method for an internal combustion engine according to any one of claims 1 to 3, wherein the timing for releasing the reduction of the engine output is determined according to the hydraulic pressure supplied to the forward clutch. An operation control method for an internal combustion engine, comprising: