JPS63163068A - Control method for operation of internal combustion engine for vehicle with automatic transmission - Google Patents

Abstract

PURPOSE:To prevent an internal combustion engine from decreasing its idle speed to be changed, by increasing an output of the engine when a speed of a turbine in a fluid coupling of an automatic transmission decreases to a predetermined value or less, in case of the engine under an anticreep control. CONSTITUTION:Under an anticreep control, a drum rotary speed Nod of an OD clutch 17 decreases to a predetermined value Nset or less, and when a forward clutch 28 is detected to be engaged by any trouble, an output of an engine is increased. In this way, an engine speed is avoided from rapidly large dropping down even if it temporarily drops, and the increase of idle vibration and the generation of an engine stall can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for controlling the operation of an internal combustion engine used in vehicles such as automobiles, and in particular anti-creep control (creep reduction control) by reducing the engagement pressure of a forward clutch. The present invention relates to a method for controlling the operation 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 generally include a fluid coupling such as a hydraulic torque converter that applies rotational power to a pump member from a prime mover such as an internal combustion engine, and a fluid coupling such as a hydraulic torque converter that provides rotational power to a pump member from a turbine member of the fluid coupling. and a planetary gear type gear transmission which can be switched between a plurality of gear stages by engaging and disengaging a plurality of frictional engagement devices. The gear position can be changed according to a predetermined shift pattern depending on the vehicle.

Conventionally, in the automatic transmission for vehicles as described above, when the manual shift range is set to a driving range such as the D range, the accelerator pedal is released and the vehicle speed is substantially zero. In other words, even during idling, the gear transmission does not enter the neutral state, but is set to the first gear, so that the vehicle starts with excellent responsiveness to the depression of the accelerator pedal.
However, if the gear transmission is set to the first gear during idling operation, the output of the internal combustion engine is transmitted to the forward running input member of the gear transmission via a fluid coupling, resulting in large idling vibrations. In addition, creep occurs, and in order to completely stop the vehicle, the brake pedal must be pressed relatively hard to activate the vehicle running brake, and furthermore, the drag of the fluid coupling at this time causes the brake pedal to stop when the vehicle is idling. It is known that the fuel economy of the engine deteriorates, and the temperature of the hydraulic fluid in the fluid coupling increases.

In view of the above-mentioned problems, when the manual shift range is set to the forward travel range and the vehicle is idling when the vehicle is substantially stopped, the friction of the gear transmission is reduced so that the gear transmission is in a neutral state or equivalent to a neutral state. The so-called forward clutch, which selectively connects the output member of the fluid coupling of the engagement device, that is, the turbine member, and the input member for forward running of the vehicle of the gear transmission, is released or the engagement pressure of the forward clutch is increased when the forward gear stage is achieved. An automatic transmission for a vehicle equipped with an anti-creep control device that sets the forward clutch to a value lower than that which causes slippage, and prevents the output torque of the hydraulic torque converter from being transmitted to the forward travel input member of the gear transmission. A machine has already been proposed, for example,
No., JP-A-56-21047, JP-A-58-1285
No. 52, JP-A-58-193953, JP-A-59-6
No. 454 is shown in each publication.

-Vehicle automatic transmissions such as Niren achieve their intended purpose,
This automatic transmission for vehicles reduces idling vibration and prevents creep, allows the vehicle to come to a complete stop even if the brake pedal is not pressed strongly, and allows the hydraulic torque converter to The elimination of drag improves fuel economy during idle operation and also avoids increases in the temperature of the hydraulic fluid in the fluid coupling.

Problems to be Solved by the Invention When the forward clutch is in a released state or in a slipping state, so-called anti-creep is performed, and the forward clutch is prevented from moving due to a stick in the control valve of the hydraulic control device or a malfunction in the electronic control system. When the clutch is engaged, even if the idle speed of the internal combustion engine is feedback-controlled to a predetermined value, the speed of the internal combustion engine will temporarily decrease due to a delay in control response due to feedback control based on the engine speed. There is a sudden and large drop, which increases idle vibration and may cause engine stall.

In view of the above-mentioned problems, the present invention provides an automatic transmission that prevents the idle speed of an internal combustion engine from decreasing even if the forward clutch is engaged due to some kind of failure under anti-creep control. The purpose of this invention is to provide a method for controlling the operation of an internal combustion engine in a vehicle with a vehicle.

Means for Solving the Problems According to the present invention, the above-mentioned object is to reduce the hydraulic pressure supplied to the forward clutch when the manual shift range is set to the forward travel range and the vehicle is idling when it is substantially stopped. In an operation control method for an internal combustion engine used in combination with a vehicular automatic transmission, anti-creep control is performed to prevent the occurrence of creep by reducing the engagement pressure of the forward clutch by reducing the Achieved by an internal combustion engine operation control method characterized by increasing engine output when the turbine rotational speed of a fluid coupling of an automatic transmission or a representative rotational speed thereof falls below a predetermined value under creep control. be done.

Functions and Effects of the Invention When the forward clutch changes from the disengaged state to the engaged state, the rotational speed of the turbine member of the fluid coupling almost lags behind the change in the engaged state of the forward clutch before the engine speed decreases. Because it decreases without causing
As in the operation control method according to the present invention, if engagement of the forward clutch due to any failure under anti-creep control is detected by a decrease in the turbine rotational speed, this can be detected in real time without any time delay. is detected, and based on this, the engine output is increased, thereby avoiding a sudden and large drop in the engine speed, even if it is temporary, resulting in an increase in idling and an engine stall. This will definitely be avoided.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail by way of embodiments with reference to the accompanying drawings.

FIG. 1 diagrammatically shows the configuration of a typical automatic transmission for vehicles. The automatic transmission 1 includes a three-element, single-stage, two-phase general hydraulic torque converter 2 with a direct coupling clutch, which has a pump impeller 3, a turbine impeller 4, a stator impeller 5, and a direct coupling clutch 6, and an auxiliary transmission device. The pump impeller 3, which is an input member of the hydraulic torque converter 3, is drivingly connected to the output shaft 101 of the internal combustion engine 100, and the turbine impeller 3, which is the output member of the hydraulic torque converter 2, is connected to the output shaft 101 of the internal combustion engine 100. The wheel 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 drive wheels (not shown) of the vehicle via a differential gear.

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

The operations of the fuel injector 102 and the ignition timing control device 103 are controlled by an engine control computer 70. The engine control computer 70 includes an intake pipe pressure sensor, an engine speed sensor,
Engine control sensor group 71 including water temperature sensor etc.
Various information necessary for engine operation control is input from the transmission control computer 60 and the fuel injection amount and ignition timing are determined according to this information, and the control signals are sent to the fuel injector 102 and the ignition timing control device 103.
It is designed to output to each of the following.

The internal combustion engine 100 has an idle speed control well 104 in the intake system that controls the amount of intake air during idling operation, and the idle speed control well 104 is opened according to the engine speed by the engine control computer 70. The idle rotation speed is feedback-controlled to a predetermined value by controlling the amount. The idle speed control value is set to a value higher by a predetermined amount when the manual shift range of the automatic transmission is in the N range or P range than when it is in a driving range such as D range or R range, Also, even in the forward travel range such as the D range, the N
It may be set to the same value as when in range or P range.

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

The auxiliary gear transmission 10 includes a sun gear 12 and a sun gear 12.
A ring gear 13 provided in the same window as the sun gear 13, a planetary pinion 14 that is located between the sun gear 12 and the ring gear 13 and meshed with the two, a carrier 15 that rotatably supports the planetary pinion 14, and a carrier 15 for the sun gear 12. One-way clutch (F) that prevents counterclockwise rotation
O) 16, an OD clutch (Co) 17 that selectively connects the sun gear 12 and the carrier 15, and an OD clutch that selectively fixes the sun gear 12 to the transmission case.
The carrier 15 is drivingly connected to the input shaft 9, and can be switched between two gears by selective engagement of the OD clutch 17 and the OD brake 18. There is.

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.
A front ring gear 22 provided concentrically with the front sun gear 20, a rear ring gear 23 provided concentrically with the rear sun gear 21, and a front planetary pinion 24 located between the front sun gear 20 and the front ring gear 22 and meshed with both. , a rear planetary pinion 25 that is located between the rear sun gear 21 and the rear ring gear 23 and meshes with them; a front carrier 26 that rotatably supports the front planetary pinion 24; and a rear planetary pinion 26 that rotatably supports the rear planetary pinion 25. The rear carrier 27 and the front ring gear 22, which is an input member for forward travel of the main gear transmission 11, are connected to the auxiliary gear transmission 10.
a forward clutch (C+) 28 selectively connected in a torque transmission relationship to the ring gear 13, which is an output member of the
Two direct clutches (C2) that selectively connect the intermediate shaft 19 and the ring gear 13 in a torque transmission relationship, a shift brake (B1) 30 that selectively fixes one intermediate shaft to the transmission case, and a rear career 2
Another shift brake (B2) 31 selectively fixes the rear carrier 27 to the transmission case, and a one-way clutch (F2) that locks the left rotation of the rear carrier 27.
l) 32, 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 engaged and released in respective predetermined combinations. By doing so, it is possible to switch between a plurality of gears, including three forward gears and one reverse gear.

The gear transmission 7 is connected to the auxiliary gear transmission 10 and the main gear transmission by engaging and disengaging the plurality of clutches and the plurality of brakes of the auxiliary gear transmission 10 and the main gear transmission 11 according to the table shown below. In cooperation with the gear transmission 11, a plurality of gears, including three forward gears including an overdrive gear and one reverse gear, are selectively achieved.

2nd speed oxoxxx△Δ D 2nd speed O××××O△× 3rd speed
OxO○xxx△n 4th gear OOO×
×××△ji 5th gear % ooxxx○×× 1st speed ○×○xxxx△△ S 2nd gear ○×××O○△×1 Season 3rd gear
O×○O×××ΔL th-speed ○×○
×O×Δ△ Season 2nd speed Q x x x O
O∆× In this table, the O mark indicates that the relevant clutch or brake is engaged, the This indicates that it is engaged (locked) during engine drive, which drives the drive wheels from the side, and released (free) during engine braking, where the internal combustion engine is driven from the drive wheels side.

Note that in the L range, an upshift to the second gear is not performed, and only a downshift from the second gear to the first gear is performed.

Clutch 1 of the auxiliary gear transmission 10 and the main gear transmission 11
7, 28, 29 and brakes 18, 30 and 31 are hydraulically operated, which are driven by hydraulic servo devices to selectively engage and operate, and hydraulic control controls the supply and discharge of hydraulic pressure to and from the hydraulic servo devices. A well-known general system that is predetermined in accordance with vehicle speed and throttle opening for each manual shift range by control by an electronic control device including a microcomputer that instructs switching of the oil path of the device and the hydraulic control device η. By engaging and disengaging the clutch and the brake in the combinations described above according to a typical speed change pattern, the gear stage of the gear transmission 7 is switched and set.

FIG. 2 shows the main parts of one embodiment of the automatic transmission for a vehicle according to the present invention. The hydraulic control device for speed change control has an idle control valve 36 that is switched by a solenoid 37, and a port a of the idle control valve is connected to an oil passage 38a and an oil passage 38 having a throttle 47a in the middle.
, the other port b is in the middle (, diaphragm 47b
The oil passage 38b and the oil passage 38 are connected to the forward port of the manual shift valve 39, respectively, and these ports are connected to the forward port of the manual shift valve 39 when the manual shift range is set to a forward travel range such as the D range, S range, or L range. Line hydraulic pressure is always supplied from the valve 39. Note that the manual shift valve 39 is connected to a line oil pressure control valve (primary regulator valve) 41 through an oil passage 40, and is connected to a line oil pressure control valve (primary regulator valve) 41.
is connected to an oil pump 43 by an oil passage 42.

In addition to ports a and b, the idle control valve 36 has two ports e and ``.Port e is connected to a relief valve 46 equipped with an oil passage 44 and a throttle port 45, and port r is connected to an oil passage 48. It 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 port a to port e as shown in the figure, and at the same time connects port a to port e. A and port ``a'' are connected, and when the solenoid device 37 is not energized, port r is separated from port e and connected to port b.

Therefore, when the solenoid 37 of the idle control valve 36 is energized when the manual shift range is in a forward travel range such as the D range, the oil pressure determined by the relief setting pressure of the relief valve 46, which is lower than the line oil pressure, is applied to the forward clutch 28. On the other hand, when the solenoid 37 is not energized, the oil is supplied to the oil chamber 35b.
Line oil pressure is supplied to b.

The hydraulic servo device 33 of the forward clutch 28 includes a 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 oil pressure supplied to the oil chamber 35b. As a result, the forward clutch 28 is engaged and the clutch engagement pressure is increased in accordance with an increase in the oil pressure in the oil chamber 35b.

The relief setting pressure of the relief valve 46 is set to a hydraulic pressure equal to the servo hydraulic pressure at which the forward clutch 28 causes slippage and the forward clutch 28 is just about to start transmitting torque. When a hydraulic pressure equal to the relief setting pressure of the relief valve 46 is supplied to the forward clutch 28, the forward clutch 28 is set in a state where it can slip just before starting torque transmission. This performs anti-creep control. Note that when line oil pressure is supplied to the oil chamber 35b of the forward clutch 28, the forward clutch 28
is fully engaged and connects the ring gear 13 of the auxiliary gear transmission 10 and the front ring gear 22 of the main gear transmission 11 in a perfect torque transmission relationship without slippage.

Power supply control to the solenoid 37 of the idle control valve 36 is performed by a transmission control computer 60.

Transmission control convenience store Taro 0 is
It includes a general microcomputer, and receives information regarding the opening of the throttle valve of the internal combustion engine 100 from the throttle opening sensor 62, information regarding the vehicle speed from the vehicle speed sensor 63, and information regarding the manual shift range from the shift position switch 64. The brake switch 65 outputs information regarding whether or not the foot brake or parking brake of the vehicle is in braking operation, and the OD clutch drum rotation speed sensor 66 outputs information as a rotation speed representative of the rotation speed of the turbine impeller 4 of the hydraulic torque converter. Each information regarding the drum rotation speed of the clutch 17 is given, and anti-creep control is performed by controlling the energization to the solenoid 37 according to the flowchart shown in FIG. It is designed to control output.

Next, with reference to the flowchart shown in FIG. 3, anti-creep control and the manner in which the internal combustion engine operation control method according to the present invention is implemented will be explained. The routine of the flowchart shown in FIG. 3 is repeatedly executed at predetermined time intervals or at predetermined crank angles.

In step 100, information is input from various sensors.

In step 101, it is determined whether anti-creep control conditions are satisfied. The anti-creep control conditions may be set in various ways, for example, when the manual shift range is a forward travel range such as D wrench, S range, or L range, and the internal combustion engine 100
The throttle circuit is in the idle circuit position and the vehicle speed is 0.
It may be less than a predetermined value close to , and the vehicle may be braking.

When the anti-creep control condition is satisfied, the process proceeds to step 102, whereas when the anti-creep control condition is not satisfied, the process proceeds to step 107.

In step 102, it is determined whether the flag F1 is 1 or not. Flag F is a flag indicating whether or not anti-creep control is being executed. When flag F is -1, it means that anti-creep control is already being executed, and in this case, the process advances to step 104. On the other hand, if it is not Fl-1, the process advances to step 103.

In step 103, energization of the solenoid 37 of the idle control valve 36 is started. As a result, a predetermined oil pressure lower than the line oil 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 gear is achieved, causing the forward clutch 28 to slip. set to the value.

At this time, the forward clutch 28 slips, which prevents the output torque of the hydraulic torque converter 2 from being transmitted to the front ring gear 22, which is the input member for forward travel of the gear transmission 7, which causes idle vibration. is reduced, and the occurrence of creep is prevented.

Further, in step 103, the flag F is set to 1, and the process then proceeds to step 104.

In step 104, it is determined whether the drum rotation speed Nod of the OD clutch 17 is equal to or less than a predetermined value N5f3L. When Nod<N5et, the normal anti-creep control in which the forward clutch 28 slips as described above is being performed and the ground reaction force from the wheels is not acting on the turbine impeller 4 of the hydraulic torque converter 2. At this time, this routine ends, but when N □d< N set, O
This is when the drum rotational speed of the D clutch 17 has abnormally decreased, and at this time, the forward clutch 28 is brought into an engaged state for some reason, and the process proceeds to step 105 assuming that the anti-creep control has failed.

In step 105, it is determined whether the flag F2 is 1 or not. Flag F2 is a flag indicating whether or not anti-creep control has failed.
When it is 2-1, the engine output increase command has already been output due to a failure of anti-creep control,
On the other hand, when it is not F2-1, it means that the engine output increase command has not been output yet, and in this case, step 106
Proceed to.

In step 106, an engine output increase command signal is output to the engine control computer 70. When the engine control computer 70 receives this engine output increase command signal, the engine control computer 70 immediately increases the opening amount of the idle speed control valve 104 to increase the engine output.

As a result, an increase in the engine output of the internal combustion engine 100 is started almost simultaneously with the occurrence of the anti-creep control failure, and as shown in FIG. 4, a large drop in engine speed due to the anti-creep control failure is avoided. be done.

Further, in step 106, flag F2 is set to 1.

Step 107 is a step executed when the anti-creep control condition is not satisfied, and this step 1
At step 07, it is determined whether the flag F1 is 1 or not. When the flag is Fl-1, step 108
Proceed to.

In step 108, energization to the solenoid 37 of the idle control valve 36 is stopped. As a result, line oil pressure is supplied to the oil chamber 35b of the forward clutch 28, thereby increasing the engagement pressure of the forward clutch 28 and canceling the anti-creep control.

Further, in step 108, the flag Fl is set to 0, and the process then proceeds to step 109.

In step 109, it is determined whether the flag is F2-1. When the flag is F2-1, the process advances to step 110.

In step 110, output of the engine output increase command signal to the engine control computer 70 is stopped. As a result, the idle speed control valve 104 resumes normal feedback control.

Further, in step 110, flag F2 is set to 0.

In addition, in the above-mentioned embodiment, the hydraulic torque converter 2
The drum rotation speed of the OD clutch 17 is used as the rotation speed representative of the rotation speed of the turbine blade -1ff4, but this may be other representative rotation speed such as the drum rotation speed of the forward clutch 28. The rotation speed of the turbine impeller 4 itself may be used.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited thereto.
It will be apparent to those skilled in the art that various embodiments are possible within the scope of the invention.

[Brief explanation of the drawing]

Figure 1 is a schematic configuration diagram showing a general automatic transmission for vehicles.
FIG. 2 is a schematic configuration diagram showing an example of a control device used to implement the driving control method and idle operation control method for a vehicle automatic transmission according to the present invention, and FIG. 3 shows an example of the implementation procedure of anti-creep control. The flowchart shown in FIG. 4 is a graph showing the control characteristics of the operation control method according to the present invention. 1...Automatic transmission for vehicles, 2...Hydraulic torque converter, 3...Pump impeller, 4...Turbine impeller. 5... Stator impeller, 6... Direct clutch, 7...
...Gear transmission, 8...Output shaft, 9...Input shaft,
DESCRIPTION OF SYMBOLS 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, 1
8...OD brake. 19... Intermediate shaft, 20... Front sun gear, 21
...Rear sun gear, 22...Front ring gear,
23... Rear ring gear, 24... Front planetary pinion, 25... Rear planetary pinion, 2
6...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 room. 36... Idle control valve, 37... Solenoid, 3
8.38a, 38b... Oil path, 39... Manual shift valve, 40... Oil path, 41... Line hydraulic control valve, 42... Oil path, 43... Oil pump, 44・
...Oil passage, 45... Throttle port, 46... Relief valve, 47a, 47b... Throttle, 48... Oil passage, 60
...transmission control computer,
62... Throttle 88 degree sensor, 63... Vehicle speed sensor, 64... Shift position switch, 65...
・Brake switch, 66... Engine speed sensor, 6
7...OD clutch drum rotation speed sensor, 70...
Engine control computer, 71... Engine control sensor group, 100... Internal combustion engine, 10
1... Output shaft, 102... Fuel injector, 10
3...Ignition timing control device. 104... Intake air amount control device patent applicant Toyota Motor Corporation representative
Patent Attorney Akashi RokiFigure 3Figure 4

Claims (1)

[Claims] When the manual shift range is set to the forward driving range and the vehicle is idling when it is essentially stopped, the hydraulic pressure supplied to the forward clutch is reduced to reduce the engagement pressure of the forward clutch and prevent the occurrence of creep. In an operation control method for an internal combustion engine used in combination with a vehicular automatic transmission in which anti-creep control is performed to prevent 1. A method for controlling the operation of an internal combustion engine, comprising increasing engine output when the rotational speed of the engine falls below a predetermined value.