JPH0519024B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an internal combustion engine control device for a vehicle equipped with an automatic transmission, and more specifically, to a control device for an internal combustion engine for a vehicle equipped with an automatic transmission. The present invention relates to a control device for an internal combustion engine configured to reduce engine output.

(Prior art) A vehicle equipped with an automatic transmission automatically selects the optimum gear stage according to the driving conditions determined from the vehicle speed and engine load condition, and changes the driving conditions while driving. If this occurs, the gear will be automatically shifted to another gear in response to the change. For example, if we take a multi-stage clutch type automatic transmission as an example, when changing gears, that is, when each clutch is operated, the clutch pressure must be given a hydraulic characteristic that is commensurate with the driving force of the engine and most suitable for the gear shift at that time. If this is not satisfied, the engine speed may exhibit a revving phenomenon, or a shock, commonly called shift shock, may occur when torque is retransmitted due to a sudden change in the degree of clutch slippage, and the occupants may You will feel uncomfortable. Therefore, in order to eliminate such inconveniences, various proposals have been made to control the engine output during gear shifting, one example of which is the technique described in Japanese Patent Application Laid-Open No. 55-69738. This technology is configured to detect a speed change signal, set an optimal period based on the engine speed at that time, and control the engine output during that period.

(Problems to be Solved by the Invention) However, in the above-mentioned prior art, a shift signal is required to determine whether or not to reduce the engine output during control, so the configuration is complicated and the processing of the signal transmission system is The disadvantage is that the complexity has increased. Furthermore, as a result of controlling based on the gear shift signal, there is the inconvenience that it is not possible to eliminate the transmission shock caused by clutch slippage that is not related to gear shifting, resulting in discomfort for the occupants and poor engagement of the clutch, etc. There was an inconvenience in that it was not possible to deal with the wear of parts and the resulting deterioration over time.

Therefore, an object of the present invention is to eliminate such drawbacks of the prior art, and to detect the gear shifting operation of a vehicle and control the engine output without using a gear shifting signal to determine whether or not to reduce the engine output. In addition to simplifying the configuration by making it possible to
It is an object of the present invention to provide a control device for an internal combustion engine for a vehicle equipped with an automatic transmission that reduces processing complexity of a signal transmission system.

Furthermore, passenger discomfort caused by clutch slippage not caused by gear shifting, clutch wear,
It is an object of the present invention to provide a control device for an internal combustion engine for a vehicle equipped with an automatic transmission, which eliminates inconveniences such as aging deterioration caused by this, saves unnecessary energy consumption, and improves fuel efficiency.

(Means for Solving the Problems) In order to solve the above-mentioned object, a control device for an internal combustion engine for a vehicle equipped with an automatic transmission according to the present invention is configured to control engine speed and engine load as shown in FIG. and vehicle speed; means 12 for setting a standard engine speed for each gear from the detected engine load and vehicle speed; and detecting the standard engine speed for each set gear. a means 14 for identifying the currently engaged gear by comparing the engine speed with the engine rotation speed; a means 16 for detecting the destination gear by monitoring the gear switching operation; The ratio between the corresponding standard engine speed and the detected engine speed is determined, and when the ratio is greater than or equal to the first value, regardless of the presence or absence of gear switching operation,
While reducing the engine output, find the ratio between the standard engine speed corresponding to the destination gear and the actual engine speed, and when the ratio is less than the second value, reduce the engine output. The engine output control means 18 is configured to stop the reduction in engine output.

(Function) The ratio between the standard engine speed corresponding to the specified gear and the detected engine speed is determined, and when the ratio is greater than or equal to the first value, the gear switching operation is determined. Since the structure is configured to reduce the engine output regardless of whether the engine output is present or not, a shift signal is no longer required to determine the decrease in engine output, and furthermore, it is possible to prevent aging or abnormalities in the transmission caused by reasons other than shifting. It can be quickly detected and dealt with.

(Embodiment) Hereinafter, an embodiment of a control device for an internal combustion engine for a vehicle equipped with an automatic transmission according to the present invention will be described with reference to FIG. 2 and subsequent figures.

FIG. 2 schematically shows the overall structure of the apparatus, and will be explained according to the figure. Reference numeral 20 indicates the main body of the internal combustion engine. An intake passage 22 is connected to the engine body 20, and an air cleaner 24 is installed at the tip side of the intake passage 22.
is attached. The intake air introduced from the air cleaner 24 reaches the engine main body through a throttle valve 26 that operates in conjunction with an accelerator pedal (not shown) on the floor of the driver's seat of the vehicle. An internal combustion injection valve (not shown) is provided at an appropriate position near the combustion chamber (not shown) in the intake passage 22 to supply fuel, and the intake air is mixed with fuel and enters the combustion chamber and enters the piston. After being compressed by a spark plug (not shown), it is ignited and exploded, driving a piston. The piston driving force is converted into rotational motion and extracted from the engine output shaft 28.

A power transmission section 30 is connected to a rear stage of the engine main body 20. In this figure, the engine output shaft 28 is shown as an operation diagram for convenience of understanding, but the engine output shaft 28 is connected to the power transmission section 30.
The turbine runner 32b is connected to a torque converter 32 and its pump impeller 32a, and its turbine runner 32b is connected to a main shaft 34 which is a transmission input shaft. In this embodiment, one countershaft 36, which is a transmission output shaft, is juxtaposed to the main shaft 34, and between the two shafts are a first gear G1, a second gear G2, and a third gear G.
3rd and 4th speed gears G4 are provided (reverse gear etc. are omitted for simplicity), and each gear is equipped with multi-plate clutches CL1, CL2, CL3,
CL4 is correspondingly provided. Also, 1st gear G1
A one-way clutch 38 is attached to the.

A crank angle sensor 50 consisting of an electromagnetic pickup or the like is provided on a rotating part such as a distributor (not shown) near the engine main body 20, and detects the crank angle position of the piston and detects the position at every predetermined crank angle. An intake pressure sensor 52 is provided at an appropriate position in the intake passage 22 to output a signal and detect the engine load state through the pressure of intake air.
Further, a water temperature sensor 54 is provided in the cooling water passage (not shown) of the engine body 20 to detect the engine temperature, and a second temperature sensor 56 is provided at an appropriate position in the intake passage 22 to detect the temperature of the intake air. Detect temperature.
Furthermore, a throttle sensor 58 consisting of a potentiometer or the like is installed near the throttle valve 26 in the intake passage.
is provided to detect the opening degree of the valve. Furthermore, a vehicle speed sensor 59 consisting of a reed switch or the like is provided at an appropriate position near the power transmission section 30 and outputs a signal proportional to the traveling speed of the vehicle. These sensors 5
Outputs 0, 52, 54, 56, 58, and 59 are sent to engine control unit 60. FIG. 3 is a block diagram showing details of the engine control unit 60. As shown in the figure, the outputs of the intake pressure sensor 52, etc. are input to the control unit 60, and then first input to the level conversion circuit 62. The signal is amplified to an appropriate level and input to the microcomputer 64. The microcomputer 64 has an input port 64
a, A/D conversion circuit 64b, CPU64c, ROM
64d, a RAM 64e, an output port 64f, a flag register, and an interrupt timer counter (both not shown), and the output of the level conversion circuit 62 is input to the A/D conversion circuit 64b and converted into a digital value. It is temporarily stored in RAM64e. Similarly, the outputs of the crank angle sensor 50 and the like are waveform-shaped by a waveform shaping circuit 66 in the engine control unit 60, and then input into the microcomputer via the input port 64a.
The signals are temporarily stored in the RAM 64e, and the CPU 64c calculates the engine speed and vehicle speed from these input signals. CPU64 in microcomputer
c calculates control values for engine operation based on these input values and calculated values in accordance with instructions stored in the ROM 64d. In this case, there are three types of control values: ignition timing, fuel injection amount, and throttle valve opening.
The basic map value as shown in Fig. 5 stored in the 4d is searched from the engine speed and intake pressure, the basic ignition timing is subtracted, and the final ignition is determined by correcting it from the output of the water temperature sensor, etc. The timing is determined and outputted through the first output circuit 68 to drive the ignition device 70 consisting of an igniter or the like to ignite the air-fuel mixture in the combustion chamber via the spark plug. Regarding the fuel injection amount, similarly, the same kind of map value is searched from the engine speed and intake pressure to determine the basic injection amount, and then the correction value is calculated to calculate the final injection amount, and the second output is Fuel injector 74 via circuit 72
and supplies fuel through the fuel injection valve. The fuel injection device 74 includes a solenoid valve and its drive circuit, and adjusts the amount of fuel supplied by controlling the duty of the solenoid valve to variably control the injection time. Further, in this control device, the throttle valve 26 is configured to be able to open and close independently of the operation of the accelerator pedal under predetermined operating conditions.
The microcomputer 64 calculates the control value and outputs it to the third output circuit 7 under predetermined operating conditions.
6 to the throttle valve drive circuit 78. This throttle valve drive circuit 78 includes a pulse motor and its drive circuit, and drives the throttle valve 26 in an appropriate direction independently of the depression position of the accelerator pedal.

Returning to FIG. 2 again, a shift lever position switch 82 is provided to detect the lever position of a shift lever (not shown) on the floor of the driver's seat of the vehicle, and the output of the sensor 82 is transmitted to the throttle sensor 58 and It is sent to the speed change control unit 84 together with the output of the vehicle speed sensor 59. Figure 4 shows the speed change control unit 8.
4, as shown in the figure, this unit has approximately the same configuration as the engine control unit described above, and the output of the throttle sensor 58, the vehicle speed sensor 59, and the shift lever position switch 82 are respectively The signal is inputted into the second microcomputer 90 via the level conversion circuit 86 and waveform shaping circuit 88, input port 90a and A/D conversion circuit 90b, and stored in its RAM 90f. in micro computers
The CRS 90c searches for a shift pattern stored in the ROM 90d, calculates a control value, and outputs the control value to the transmission 9 through an output port 90f and an output circuit 92.
A shift command is output to 4. The transmission device 94 is equipped with a solenoid valve drive circuit for the shift valve, and drives the solenoid valve as appropriate according to the command value to stop the hydraulic pressure supply to the clutch of the engaged gear and also to stop the hydraulic pressure supply to the clutch of the next gear. Start supplying hydraulic pressure to and change gears. Further, the speed change control unit 84 and the engine control unit 60 are configured to be able to communicate with each other via a communication interface (not shown).

Next, the operation of this device will be explained with reference to FIG. The operation of this device is controlled by the engine control unit 60 described above, and this program is executed for a predetermined time such as 30 ms while the unit calculates control values such as ignition timing and fuel injection amount. Interrupt activation at every predetermined crank angle.

First, in S100, the engine speed Ne, throttle valve opening θth, and vehicle speed V are read from the RAM 64e from the outputs of the crank angle sensor 50, throttle sensor 58, and vehicle speed sensor 59, and
Next, in S102, the standard rotational speed Ne-STDn for each speed stage from 1st to 4th gear is determined from the vehicle speed V and the throttle valve opening θth, that is, NeSTD1, Ne-
Search for STD2, Ne-STD3, and Ne-STD4.
This will be explained with reference to FIG. 7. During engine operation, the engine speed can be set to a standard value for each speed stage depending on the vehicle speed and the throttle valve opening. The figure shows the case of 2nd speed, where the horizontal axis shows the vehicle speed, the vertical axis shows the standard engine speed, and the throttle valve opening characteristic curves of 1/2, 1/4, etc. are set. By doing so, it is possible to determine the standard engine speed at a specific vehicle speed and throttle valve opening. The characteristic diagram as shown in the figure is
It is stored as a table in the ROM 64d. still,
The vehicle speed is set at several points, and the throttle valve opening is set at every 1/4.
The intermediate value is obtained by interpolation calculation. In the operation of S102, the standard rotation speed is searched for each of the four speed stages and temporarily stored in the RAM 64e.

Next, after confirming that the flag (described later) is turned off in S104, the four standard engine speeds Ne-STDn, which were searched in S106, are
That is, S10 among Ne-STD1 to Ne-STD4
The value closest to the actual engine speed Ne read at 0 (hereinafter referred to as "Ne-STDA") is selected, and the speed stage to which it belongs is estimated to be the current speed stage (hereinafter referred to as "A"). Subsequently, in S108, a dead zone value ΔA is searched. This will be discussed later.

Next, in S110, the rotational blur rate is calculated as follows based on the current stage standard engine speed Ne-STDA specified in the previous step and the actual engine speed Ne.
Calculate RNeA.

RNeA=Ne/Ne-STDA Next, in S112, it is determined whether or not the rotational deviation rate is within the dead zone.To explain the above with reference to FIG. That is, when the gear of the current stage A) is engaged, the standard engine speed Ne - STDA should be approximately equal to the actual engine speed Ne, and therefore the rotational deviation rate RNeA is also approximately "1". It should be. In this state, when an up or down shift command is issued from the transmission control unit 84, the transmission 94 receives it and stops supplying hydraulic pressure to the engaged gear, and supplies hydraulic pressure to the destination gear (hereinafter referred to as "B"). , and then change gears. As mentioned above, during the switching, the engine speed changes suddenly due to changes in the load condition, causing a shift shock, which is an inconvenience. It should appear. The present invention has been made by focusing on this point, and measures the speed change shock by monitoring the rotational deviation rate and taking measures when the rotation deviation rate leaves "1" and further leaves the appropriately set dead zone 1±ΔA. Determine when it is necessary,
It is designed to reduce engine output. Therefore, even after the engine output starts to decrease, the rotational deviation rate continues to be monitored, and it is determined that the dead band range of the next stage B is "1".
Control is stopped when the speed falls within ±△B". Therefore, for these dead zones △A and △B, appropriate boundary points are selected to determine when such a shift shock countermeasure is required. Figures 9 and 10 show the dead zone △A of the current stage and the dead zone △B of the destination stage, which can be set individually for each speed stage as shown in the figure.
It is stored as a table value in the ROM 64d.

Returning to the flow chart in Figure 6 again, S112
If it is determined that the rotational deviation rate is within the dead zone, it means that the gear is currently firmly engaged, or even if it starts to disengage, it is not enough to reduce the engine output. The program is ended without reducing the engine output, and after the flag is turned off if it has not been turned off (S114, 116).

If the determination in S112 is negative, the process proceeds to S118, where the engine output is reduced, and the flag is turned on in S120. That is, this flag means that engine output control has started. Subsequently, in S122, it is determined whether or not the gear is to be changed. This is done by making an inquiry from the engine control unit 60 to the transmission control unit 84. As a result, if it is determined that the gear is to be shifted, the process moves to S124, where the unit 84 is similarly inquired as to which speed gear the destination gear B is, and the program is terminated.

Once the flag is turned on in S120, the next time the program starts, it will move from S104 to S126,
Therefore, from among the four standard engine speeds,
The standard value Ne-STDB of the destination stage B detected in S124 is selected, and then in S128 its dead zone value △B
is searched from ROM64d.

Next, in S110, the rotational deviation rate RNeB at the destination stage B is calculated, and in S112, the rotational deviation rate RNeB at the destination stage B is calculated.
It is determined whether the engine has entered the dead zone or not, and if it has not yet entered the dead zone, the engine output remains reduced. In this control, even if it is confirmed that no shift command has been issued as a result of the inquiry to the shift control unit 84 in S122, the engine output is reduced (S130). In this case, there is no shift, so engine output control will continue until it is determined in S112 that the rotational deviation rate has converged within a predetermined range, but by reducing the engine output, the engine rotational speed will decrease. As a result, the rotational deviation rate quickly converges within a predetermined range. Therefore, the clutch does not wear out and deteriorate over time, and the engine does not cause revving up, which causes discomfort, and wastes fuel unnecessarily. Note that the number of times the loop has passed is counted in S130, and if the counted value exceeds a predetermined value, a fail-safe operation is performed in S132, and a warning is issued if desired.
Incidentally, this fail judgment is carried out by attaching a timer counter to the microcomputer,
This may be done by starting the timer counter and measuring time when the shift is denied in the determination in S122. In addition, in S112, the rotational deviation rate RNeB is within the dead band range of destination stage B "1±△
When the engine output reaches B'', as described above, the reduction in engine output is stopped and restored to the original value (S114), and the flag is turned off (S116).

Regarding the above, to explain the case of controlling engine output using ignition timing as an example with reference to Fig. 8, engine output reduction command (Flow chart S118 of Fig. 6)
In response to this, the ignition timing is retarded at once to reduce engine output, and an output reduction stop command (S114)
Accordingly, the ignition timing is gradually adjusted in the advance direction to restore the engine output. FIG. 11 shows a correction map for calculating this retardation correction, which can be searched by engine speed and intake pressure similarly to the basic map shown in FIG. 5. This correction value shall be set proportionally according to the basic ignition timing, and if the basic ignition timing is large in the advance direction, the correction value will be large, and if the basic ignition timing is small in the advance direction, the correction value will be large. Set the value to be small. or,
When correcting the retardation and return advance angle, the retardation angle was configured to be retarded all at once and then gradually returned, but it is also possible to gradually retard the angle or advance the angle all at once, as shown by the broken line in Fig. 8. . The lower part of FIG. 8 shows the case where the engine output is controlled using the throttle valve opening as an example. In this case, the throttle valve 26 is driven in the closing direction as shown by the solid line in response to the control start command. to reduce engine output. In the figure, the broken line indicates the throttle valve opening degree corresponding to the accelerator pedal position. In the fuel injection control, although not shown, the injection control value is added, subtracted, multiplied and divided by a predetermined value to reduce the injection time or cut the fuel to reduce the output. Furthermore, it goes without saying that a carburetor may be used in place of the fuel injection device, and in that case, the injection amount will be similarly reduced or stopped through appropriate means.

FIG. 12 is a flow chart showing another example of the operation of this device.
This example also differs from the previous example in that the output starts from reading the engine speed, etc., and the output does not decrease if the rotational deviation rate of the current gear is within a predetermined range, but decreases if it is outside the predetermined range. However, the difference is that when the output is reduced, the degree of reduction is made variable according to the rotational deviation rate. That is,
S212 If it is determined that the rotational deviation rate exceeds the current stage dead zone, proceed to S218 and RNe-RPWR
Search the output down rate RPWRA from the current stage rotational deviation rate RNeA from the table and set the control value to 25%, for example.
It is decided that it is down etc. This output down rate RPWR is shown in FIGS. 8 and 13 above. Such characteristic diagrams are made into tables for each speed stage, and micro-
It is stored in the ROM 64d of the computer. When output control is started for the first time, the control value is determined based on the down rate determined in S222, and, for example, the first
Issue a retardation command as shown in Figure 3. Thereafter, the flag is turned on, the destination stage is detected, and the program ends (S224-228).

Therefore, when the next program starts, S208
After calculating the deviation rate of the current stage, the flag is determined to be on in S210, and as a result, the process proceeds to S230 and thereafter to calculate the rotational deviation rate of the destination stage (S232 to 234), and
Result that is determined to be flag on even in S220
In S236, from the RPWR-RNe table, the output down rate of the destination stage is determined from the rotational deviation rate RNeB of the destination stage.
RPWRB is searched, and then in S238, the current stage output down rate and the preceding stage output down rate are compared,
The value with the smaller down rate is selected as the control value (S222, 240). In addition, the remaining configuration S242,
244 is no different from the previous example. That is, in this example,
As shown by the thick line in the characteristic curve in Fig. 13, in proportion to the smaller down rate of both rotational deviation rates,
Taking ignition timing as an example, the retard angle is increased or decreased.

This example has the advantage that it is possible to more accurately reduce the engine output in accordance with the operating condition and avoid a shift shock.

(Effects of the Invention) The control device for an internal combustion engine for a vehicle equipped with an automatic transmission according to the present invention includes means for detecting engine rotation speed, engine load, and vehicle speed; means for setting a standard engine speed for each gear, and identifying the currently engaged gear by comparing the set standard engine speed for each gear with the detected engine speed. means for detecting the destination gear by monitoring the gear shifting operation;
and the ratio between the standard engine speed corresponding to the specified currently engaged gear and the detected engine speed, and when the ratio is greater than or equal to the first value,
Regardless of the presence or absence of gear switching operation, the engine output is reduced, and the ratio between the standard engine speed corresponding to the destination gear and the actual engine speed is determined, and that ratio is the second value. Since the structure is configured to include an engine output control means that stops the reduction in the engine output when the following occurs, the structure and processing of the signal transmission system are improved in that a shift signal is not required in the engine output reduction control during gear shifting. It has the advantage of being simple. Furthermore, the engine output is controlled even if the clutch slips, etc., which is not caused by gear shifting, thereby eliminating the discomfort experienced by the occupants and reducing wear and aging of the engaging parts such as the clutch. This has the advantage that fuel efficiency can be improved by saving unnecessary energy consumption.

[Brief explanation of drawings]

Fig. 1 is a diagram corresponding to claims of the present invention, Fig. 2 is a schematic diagram showing the overall configuration of a control device for an internal combustion engine for a vehicle equipped with an automatic transmission according to the present invention, and Fig. 3 is an engine control diagram therein. FIG. 4 is a block diagram showing details of the unit; FIG. 4 is a block diagram showing details of the transmission control unit therein; FIG. 5 is an explanatory diagram showing a basic map of ignition timing used by the engine control unit to calculate ignition timing. , FIG. 6 is an explanatory diagram showing the standard engine speed used in a flow chart showing the operation of the device according to the present invention, FIG. 8 is a timing chart schematically showing the control operation of the device, and FIGS. FIG. 10 is an explanatory diagram showing dead zone values used in this operation, FIG. 11 is an explanatory diagram showing a retardation correction map for ignition timing, and FIG. 12 is a flow chart showing another example of the operation of this device. FIG. 13 is a timing chart explaining the calculation work. 20... Engine body, 26... Throttle valve, 30...
Power transmission unit, 32... Torque converter, 34... Main shaft, 36... Counter shaft, G1,
G2, G3, G4...Gear, CL1, CL2, CL3,
CL4...Clutch, 50...Crank angle sensor, 5
2...Intake pressure sensor, 58...Throttle sensor, 5
9... Vehicle speed sensor, 60... Engine control unit, 64
...Microcomputer, 70...Ignition device, 7
4...Fuel injection device, 78...Throttle valve drive circuit, 84...Transmission control unit, 90...Second microcomputer, 94...Transmission device.

Claims (1)

[Scope of Claims] 1 a. Means for detecting engine speed, engine load, and vehicle speed; b. Means for setting standard engine speed for each gear from the detected engine load and vehicle speed; c. Setting. means for identifying the currently engaged gear by comparing the standard engine speed for each gear and the detected engine speed; d) detecting the destination gear by monitoring the gear switching operation; means, and e. Determine the ratio between the standard engine speed corresponding to the specified currently engaged gear and the detected engine speed, and when the ratio is equal to or higher than a first value, the gear Regardless of the presence or absence of stage switching operation,
While reducing the engine output, find the ratio between the standard engine speed corresponding to the destination gear and the actual engine speed, and when the ratio is less than the second value, reduce the engine output. 1. A control device for an internal combustion engine for a vehicle equipped with an automatic transmission, comprising: engine output control means for stopping a reduction in engine output. 2. A control device for an internal combustion engine for a vehicle equipped with an automatic transmission according to claim 1, wherein the engine output reduction amount changes in accordance with the ratio. 3. The automatic engine according to claim 1 or 2, wherein the engine output control means controls the engine output from any one or a combination of ignition timing, fuel supply amount, and throttle valve opening. A control device for an internal combustion engine for vehicles equipped with a transmission.