JPH0237134A - Throttle opening control device of vehicle mounted internal combustion engine - Google Patents

Abstract

PURPOSE:To prevent sudden decrease of engine output to attain stability and to self-control unnecessary output to improve responsiveness and follow-up ability by limiting the command value to a limit value when the computed command value exceeds a throttle valve moving limit value. CONSTITUTION:In a control unit 58, output of engine operating condition detecting means such as a crank angle sensor 52 and so on and an accel sensor 48 are input to a microcomputer and it sets an opening of a throttle valve 6. According to the opening output, a command value given to a pulse motor 5 for driving the throttle valve 6 is computed on every designated period. In this case, the limit of a command value is fixed not to exceed the moving limit of the throttle valve 6. Thus, there is no disadvantage that the throttle valve 6 is forcedly returned by a return spring and an unnecessary command value is not output in all closing conditions. Accordingly, the control is excellent in stability and the responsiveness and follow-up ability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a throttle opening control device for an on-vehicle internal combustion engine, and more specifically, a pulse motor is connected to a throttle valve, and the throttle valve is controlled via the pulse motor. The present invention relates to a throttle opening control device for a vehicle-mounted internal combustion engine that controls opening and closing of a vehicle.

(Prior Art) It is well known that a pulse motor is connected to a throttle valve disposed in the intake passage of an internal combustion engine, and its opening and closing is controlled according to the operating state of the engine. The technique described in JP-A-61-19946 can be mentioned. In this prior art, a command pulse to a pulse motor is calculated and outputted according to the operating state of the engine, and the throttle valve is controlled to a target opening degree.

(Problem B to be solved by the invention) Therefore, when opening and closing the throttle valve is driven by a pulse motor, a spring is attached to the throttle valve to bias it in the closing direction, and the driving force of the motor increases. It is configured so that it is forcibly returned to the idle position when it stops working. Therefore, if a command value that exceeds the fully open position of the throttle valve is output, the pulse motor will characteristically step out at the stage when the throttle valve hits the stopper, the torque will drop to zero, and the throttle valve will suddenly return to the fully closed position. As a result, the engine output is inconveniently reduced. In addition, when controlling the valve closing direction, there is no problem with the spring biasing force, but when outputting a command value that exceeds the fully closed position, a command value that does not affect the operation of the throttle valve is output, and control Dissatisfaction remained in terms of responsiveness and followability.

Furthermore, when controlling the opening and closing of the throttle valve via a pulse motor, the motor command value is output according to the deviation between the target value and the current opening, but in this case, the change in the target value is small. However, there may be cases where the rotation direction is frequently reversed. In such a case, if the output is output to the pulse motor in the same way, the throttle opening will fluctuate and the intake air amount will change, causing hunting in the engine output, making it impossible to expect stable control.

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks, and to set a limit on the command value output to the pulse motor so as not to exceed the movement limit of the throttle valve, thereby preventing the engine output from increasing or decreasing. It is another object of the present invention to provide a throttle opening control device for an on-vehicle internal combustion engine that improves control stability and suppresses unnecessary output to improve control responsiveness and followability. An object of the present invention is to provide a throttle opening control device for an on-vehicle internal combustion engine, which prevents engine output hunting by providing a dead band in a command value outputted to the - side, thereby improving control stability.

(Means and effects for solving the problems) In order to solve the above problems, the present invention detects the amount of depression of an accelerator pedal arranged on the floor surface of the driver's seat of a vehicle, as shown in FIG. A detecting means 1, an engine operating state detecting means 2 for detecting the operating state of the engine, and outputs from the engine operating state detecting means and the Agesel pedal depression amount detecting means are inputted to determine the opening degree of a throttle valve provided in the engine intake passage. Throttle opening setting means 3 to set, motor command value calculating means 4 inputting the output of the throttle opening setting means and calculating a command value to the pulse motor that drives the throttle valve, and output of the motor command value calculating means. In the throttle opening control device for an on-vehicle internal combustion engine, which comprises a pulse motor 5 that rotates upon input of a pulse motor 5, and a throttle valve 6 that is connected to the pulse motor and opens and closes an engine intake passage in accordance with the rotation thereof, the motor command value calculation means is configured such that when the calculated command value exceeds the movement limit value of the throttle/two-torr valve, the command value is limited to the limit value.

Further, an accelerator pedal depression amount detection means 1 for detecting the depression amount of an accelerator pedal arranged on the floor surface of the driver's seat of the vehicle, an engine operation state detection means 2 for detecting the operating state of the engine, the engine operation state detection means and the above-mentioned Throttle opening setting means 3 which inputs the output of the accelerator pedal depression amount detection means to set the opening of a throttle valve provided in the engine intake passage, and drives the throttle valve by inputting the output of the throttle opening setting means. A motor command value calculating means 4 which calculates a command value to the pulse motor to be operated; a pulse motor 5 which rotates by inputting the output of the motor command value calculating means; In the throttle opening control device for an on-vehicle internal combustion engine, which includes a pulse motor 6 that opens and closes, the motor command value calculation means is configured to: when the polarity of the calculated command value is reversed and the magnitude thereof is less than a predetermined value; It was configured to output the previous command value as is.

(Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Second
The figure is a schematic diagram showing the overall throttle opening control device for an on-vehicle internal combustion engine according to the present invention. Referring to the figure, reference numeral 10 indicates the internal combustion engine. The internal combustion engine 10 is equipped with an intake passage 12, and intake air introduced through an air cleaner 14 attached to the tip side enters an intake manifold 18 while its flow rate is adjusted by the throttle valve 6 described above, and is used for fuel injection. Fuel is supplied through the valve 20 and the combustion chamber 24 is supplied through the intake port where the intake valve 22 opens and closes.
flows into. The inflowing air-fuel mixture is ignited by a spark plug (not shown) and combusted, driving the piston 26, and then enters the exhaust manifold 30 through the exhaust port opened and closed by the exhaust valve 28, and passes through the exhaust pipe ( (not shown) and is released outside the engine.

Further, an accelerator pedal 32 is arranged on the floor of the driver's cabin of the vehicle in which the internal combustion engine is mounted, and the pedal is biased to the idle position by a spring (not shown) and is pressed in response to the driver's depressing action. Rotate. As shown,
The mechanical connection between the accelerator pedal and the throttle valve 6 is broken, and instead, the above-mentioned pulse motor 5 is provided near the throttle valve. The pulse motor is
It is connected to the valve shaft 6a of the throttle valve via a clutch mechanism and a reduction gear mechanism (not shown) to open and close the valve.

It should be noted that a return spring (not shown) is provided on the throttle valve shaft 6a, which constantly urges the throttle valve in the fully closed direction. The opening degree of the throttle valve is detected through a throttle sensor 40 consisting of a potentiometer or the like.

Furthermore, at an appropriate position downstream of the throttle valve in the intake passage 12,
Intake pressure sensor 42 that detects the pressure of intake air in absolute pressure
Further, an intake temperature sensor 44 for detecting the temperature of intake air is provided on the downstream side thereof, and an atmospheric pressure sensor 46 for detecting atmospheric pressure is provided at an appropriate position upstream of the throttle valve. Further, near the accelerator pedal, there is an accelerator sensor 48 which is the above-mentioned accelerator pedal depression amount detection means for detecting the amount of depression of the accelerator pedal (accelerator opening degree).
In addition, a water temperature sensor 50 for detecting the cooling water temperature is provided at an appropriate position near the combustion chamber, and a crank angle sensor 52 for detecting the crank angle of the engine is also provided at an appropriate position such as in the distributor (not shown). is established,
On the other hand, a vehicle speed sensor 54 for detecting the traveling speed of the vehicle is also provided at an appropriate position on the transmission (not shown).

The outputs of these sensors are sent to a control unit 58.

Furthermore, this control device includes an ACG sensor 60 that detects the field current of an alternator (not shown), a power steering switch 62 that detects activation/inactivation of the power steering (not shown), and an air conditioner switcher (not shown). ), a starter switch 66 that detects activation/non-operation of a starter (not shown), a battery voltage sensor 68 that detects the voltage of a battery (not shown), a shift lever ( A range selector switch 70 for detecting the range position (not shown) and a shift position switch 72 for detecting the shift position (gear) (for example, detected by referring to the solenoid excitation signal of the mission control unit) are provided for control. A brake switch 74, main switch 76, set switch 78, and resume switch 80 are also provided for powering the unit and for autocruise control.

FIG. 3 shows details of this control unit 58. In this unit, the analog output of the throttle sensor 40, etc. is input to a level conversion circuit 88, where it is converted to an appropriate level and then input to a microcomputer 90. It is converted into a digital value by the A/D conversion circuit 90a and the RA
Temporarily stored in M90e. Also, the crank angle sensor 5
The digital output, such as the second one, is waveform-shaped by a waveform shaping circuit 92 and input into the microcomputer via an input port 90b. CPU in microcomputer
90c calculates control values as described later from these inputs according to the program stored in the ROM 90d,
The signal is sent to an output circuit 94 through an output port 90f, and further drives the pulse motor 5 through a drive circuit 96 made of a transistor or the like, thereby controlling the opening and closing of the throttle valve 6.

In the above configuration, the crank angle sensor 52 and the like other than the accelerator sensor 48 correspond to the engine operating state detecting means, and the microcomputer 90 corresponds to the throttle opening setting means and motor command value calculating means.

Next, the operation of this control device will be explained with reference to the flow chart in FIG. In addition, this program is a predetermined time,
For example, it is looped and repeated every 10m5.

First, the command value θCMDn− calculated last time in SIO
Outputs 1. This command value is indicated by the number of pulses (displacement amount). As shown in FIG. 5, in this control method, the calculation cycle is set at relatively short intervals of 10 m5, and
The calculated command value is not outputted immediately, but delayed for -1 time and outputted at the beginning of the next cycle.

Next, in S12, control parameters such as the engine speed Ne and the accelerator opening θ^P are sequentially read and stored in the RAM 90.
In step S14, the reference opening degree θTHM of the throttle valve is searched from the accelerator opening degree θAP and the engine speed Ne with reference to the map stored in the ROM 90d.

Subsequently, in S16, it is determined whether the vehicle is in the idle control range. This is determined from the starter switch signal, range selector signal, vehicle speed, intake pressure, throttle opening, engine speed, etc., and especially when the engine speed is below the appropriately set deceleration speed and above the idle determination speed. It is determined that the engine is in the idle control range, and the process proceeds to step 318, where the throttle opening degree θ1dle for idle control is appropriately determined.

If it is determined in step 316 that the opening is not within the idle control range, the process proceeds to S20, where a predetermined opening θ1dle-ref is set as the idle opening. This predetermined opening degree is, for example, 10 degrees, which is the upper limit opening degree in the idle control region (however, WOT =
84 degrees).

Subsequently, in S22, it is determined whether or not the vehicle is in the auto cruise control range. This is the brake switch 74 mentioned above,
This is determined from the output signal of the auto cruise main switch 76, etc. If it is determined that the vehicle is within the auto-cruise control range, the process proceeds to S24, where the auto-cruise opening degree θcru is calculated as appropriate to maintain the set vehicle speed, and if not, the auto-cruise opening degree is set to zero in 826. do.

Subsequently, in 328, the target opening degree θT110 is calculated. This is the opening calculated so far, that is, the standard opening θT.
) IM, the maximum value is selected from the idle opening degree θidl and the auto cruise opening degree θcru.By selecting the maximum value in this way, for example, when an operating state in which the idle control area and the auto cruise control area overlap occurs, Even if there is a problem, it is possible to optimally control the throttle opening to achieve both types of control. Note that the selected maximum value is indicated by the opening degree, so in this step, it is converted into the number of pulses by dividing it by a predetermined number (opening degree per pulse).

Next, in S30, the previously calculated target value θTHOn
Deviation Δ between -1 and the target value θT II On calculated this time
θTWO is calculated, and in S32 it is determined whether the polarity of the deviation, that is, the motor rotation direction is reversed or not. If it is determined that it is reversed, then in S34 the absolute value of the deviation (regardless of the rotation direction) is determined. n step angle set appropriately,
For example, it is determined whether the angle is smaller than l step angle. The reason why it is determined whether the angle is smaller than one step angle is because a fraction below the decimal point may occur during the above-mentioned opening-pulse conversion. If it is determined that the deviation is small, then the deviation ΔθTHO is temporarily stored in S36. Specifically, the current deviation is added to the previous stored value ΔθTHO3n-1, which has already been stored, to obtain the latest stored value ΔθTHO3n. Subsequently, at 838, the current throttle opening target value θT)Ion remains the previous target value θTHOn-1, and the target value remains unchanged. If the target value is only slightly changed and the direction of rotation changes frequently, a dead zone is provided to prevent output. In this case, it is naturally not possible to output a step angle less than 1 step angle due to the characteristics of the pulse motor, but it is particularly advantageous to set n to 2 to 3 step angles. Note that if it is determined in S32 that the polarity of the deviation is not reversed, or if it is determined in S34 that the deviation (absolute value) is larger than the appropriately set step angle n, the process proceeds to S40.
The value ΔθTHOSn stored in the target value θTHOn
Add (if there is a store value) and set it as the current target value,
In the next step 342, the stored value is reset to zero for the next calculation.

Subsequently, in S44, the previous throttle opening θTHP
The previous command value θCMDn-1 outputted by the SIO is added to n-1 (pulse absolute value) to calculate the current opening, more precisely, the throttle opening θTHPn currently being moved. Subsequently, in S46, the deviation between the current opening degree and the target value is calculated to determine the current motor command value θCMOn (pulse displacement amount).

Next, in 348, it is determined whether the absolute value of the current command value exceeds the upper limit value θMAX (number of pulses), and if it does, the control value is limited to the upper limit value according to the rotation direction (S50, 52. 54). This upper limit value θMAX means the upper limit value that can be output within a computation cycle of 10 m5. That is, if the command pulse continues to be output for two or more cycles, the current opening degree cannot be calculated accurately in S44, so a limit is provided in this way.

In this flowchart, the valve opening direction is a positive value, and the valve closing direction is a negative value.

Subsequently, in step 356, the command value is re-limited. This is to determine whether or not the throttle valve can move as instructed, as described above. Specifically, the rotation direction is determined in S56, and if it is determined that it is in the valve opening direction, a control value is determined in step 358 so that the throttle valve can move according to the calculated command value. In other words, the upper limit opening θTH corresponds to the maximum opening (WOT) that the throttle valve can physically open.
Since the value obtained by subtracting the current opening degree θTHPn from MAX (pulse absolute value) is the movable range, compare that value with the calculation command value and select the smaller value.

This is because, as mentioned above, the throttle valve is biased in the fully open direction by a spring attached to the valve shaft 6a, so when a command value greater than fully open is given to the pulse motor, the throttle valve hits the stopper. This is to avoid the inconvenience of the pulse motor stepping out due to its characteristics and being immediately returned to the fully open position by the spring force, resulting in a sudden decrease in engine output. In addition, if the command value is a value in the valve closing direction, the current opening degree is a positive value calculated with the fully closed position as zero, so the control value (
The command value can be limited to a movable range by simply comparing the absolute value (absolute value) and the current opening degree and selecting the smaller value (S60). In this case, there is no problem with the urging force due to the spring in the valve closing direction, but by configuring it in this way, it is possible to limit the output of pulses that are not involved in the operation of the throttle valve, which improves calculation speed and control response. will improve. As described above, the command value calculated in this manner is stored in the RAM without being outputted when the calculation is completed, and is outputted in S10 when the program is started next time.

As mentioned above, in this embodiment, the motor command value is limited within the movable range of the throttle valve, so the throttle valve is forcibly returned by the return spring, or an unnecessary command value is output in the fully closed direction. Therefore, it is possible to realize stable control with excellent responsiveness and followability. Furthermore, since the control value is not changed when the change in the target value is minute and the polarity is frequently reversed, the control characteristics can be similarly stabilized.

Although the present invention has been described with reference to a mechanism in which the mechanical connection between the accelerator pedal and the throttle valve is completely separated, the present invention adds a pulse motor while leaving the mechanical connection such as the accelerator wire. Needless to say, it is also valid for something that is set up in a specific manner.

(Effects of the Invention) In the throttle opening control device for an on-vehicle internal combustion engine as set forth in claim 1, the motor I command value calculation means outputs the command value when the calculated command value exceeds the movement limit value of the throttle valve. Since the configuration is configured to limit the limit value to this limit value, there is no problem such as the throttle valve being forcibly returned via the return spring when controlling the valve opening direction, and the valve closing operation is also prevented when controlling the valve closing direction. It is possible to omit command values that are not related to the control, and has the advantage of excellent control stability and improved responsiveness and followability.

Further, in the throttle opening control device for an on-vehicle internal combustion engine according to claim 2, when the polarity of the calculated command value is reversed and the magnitude thereof is less than a predetermined value, the motor command value calculation means Since the structure is configured to output the command value as is, there is no problem such as changing the intake air amount by changing the throttle opening degree unnecessarily, resulting in hunting in the engine output, and it is possible to realize stable control. Equipped with

[Brief explanation of the drawing]

Fig. 1 is a diagram corresponding to claims of the throttle opening control device for an on-vehicle internal combustion engine according to the present invention, Fig. 2 is a schematic diagram showing the control device as a whole, and Fig. 3 shows details of the control unit therein. 4 is a flow chart showing the operation of the control device, and FIG. 5 is a zero system? 3 is a timing chart showing the operation of the a device. 1... Accelerator pedal depression amount detection means (accelerator sensor 4B), 2... Engine operating state detection means (crank angle sensor 52, etc.), 3... Throttle opening setting means (microcomputer 90), 4 ...Motor command value calculating means (microcomputer 90), 5...Pulse motor, 6...Throttle valve, 10...Internal combustion engine, 12...Intake path, 32...Accelerator pedal, 40
...Throttle sensor, 42...Intake pressure sensor, 4
4... Intake temperature sensor, 46... Atmospheric pressure sensor, 48
... Accelerator sensor, 50... Water temperature sensor, 52.
・・Crank angle sensor, 54 ・Vehicle speed sensor, 58・
...Control unit, 60...ACG sensor, 62...
・Power steering switch, 64...Air conditioner switch, 6
6... Starter switch, 68... Battery voltage sensor, 70... Range selector switch, 72...
Shift position switch, 74... Brake switch, 76... AC main switch, 78... AC set switch, 80... AC resume switch, 9
0...Microcomputer applicant Honda Motor Co., Ltd. agent Patent attorney Yoshi1) Yutaka

Claims (2)

[Claims] (1) a. Accelerator pedal depression amount detection means for detecting the depression amount of an accelerator pedal arranged on the floor surface of the vehicle driver's seat; b. engine operating state detection means for detecting the operating state of the engine; c. Throttle opening setting means for inputting the outputs of the engine operating state detecting means and the accelerator pedal depression amount detecting means to set the opening of a throttle valve provided in the engine intake passage; d. motor command value calculation means for inputting the output of the throttle opening degree setting means and calculating a command value for a pulse motor that drives the throttle valve; e. a pulse motor that rotates by inputting the output of the motor command value calculation means; and f. A throttle opening control device for an on-vehicle internal combustion engine comprising: a throttle valve connected to the pulse motor and opening/closing an engine intake passage according to the rotation of the pulse motor; A throttle opening control device for an on-vehicle internal combustion engine, characterized in that when a movement limit value is exceeded, a command value is limited to the limit value. (2) a. Accelerator pedal depression amount detection means for detecting the depression amount of an accelerator pedal arranged on the floor surface of the vehicle driver's seat; b. engine operating state detection means for detecting the operating state of the engine; c. Throttle opening setting means for inputting the outputs of the engine operating state detecting means and the accelerator pedal depression amount detecting means to set the opening of a throttle valve provided with an engine intake passage; d. motor command value calculation means for inputting the output of the throttle opening degree setting means and calculating a command value for a pulse motor that drives the throttle valve; e. a pulse motor that rotates by inputting the output of the motor command value calculation means; and f. A throttle opening control device for an on-vehicle internal combustion engine comprising: a throttle valve connected to the pulse motor and opening/closing an engine intake passage according to the rotation of the pulse motor; 1. A throttle opening control device for an on-vehicle internal combustion engine, characterized in that when the magnitude of the command value is less than a predetermined value, the previous command value is output as is.