JPH0674762B2 - Throttle opening control device for in-vehicle internal combustion engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a throttle opening control device for a vehicle-mounted internal combustion engine, and more specifically, a pulse motor is connected to a throttle valve, and the throttle valve is connected via the pulse motor. The present invention relates to a throttle opening control device for an on-vehicle internal combustion engine that controls opening and closing of a vehicle.

(Prior Art) It is well known to connect a pulse motor to a throttle valve arranged in an intake passage of an internal combustion engine and control the opening and closing of the pulse motor according to the operating state of the engine. The technique described in Japanese Laid-Open Patent Publication No. 61-19946 can be mentioned.
In this conventional technique, a pulse motor is controlled via a control unit composed of a microcomputer to adjust the throttle opening.

(Problems to be Solved by the Invention) A pulse motor is widely used in the field of machine tools or office machines. In that case, when the amount of movement is large, slew up to enter a high speed mode, and then slew down to decelerate. A technique for accelerating and decelerating a pulse motor by doing so is often seen. Thus, when controlling the throttle opening of the vehicle-mounted internal combustion engine via the pulse motor as in the above-mentioned conventional technique, the vehicle-mounted internal combustion engine is required to have real-time property, and therefore is the same as the control of the machine tool or the office machine. In the past, it was difficult to properly perform the acceleration / deceleration processing of the pulse motor.

Therefore, an object of the present invention is to provide an apparatus for controlling the throttle opening of an in-vehicle internal combustion engine via a pulse motor, while appropriately satisfying the real-time property and appropriately accelerating and decelerating in a predetermined operating state in which a pulse motor slew up operation is required. It is an object of the present invention to provide a throttle opening control device for an on-vehicle internal combustion engine that enables control.

(Means and Actions for Solving the Problems) In order to solve the above problems, the present invention is, as shown in FIG. 1, an accelerator pedal depression amount for detecting an accelerator pedal depression amount arranged on the floor surface of a vehicle driver's seat. The opening of the throttle valve provided with the engine intake passage by inputting the outputs of the detecting means 1, the engine operating state detecting means 2 for detecting the operating state of the engine, the engine operating state detecting means and the accelerator pedal depression amount detecting means. Of the throttle opening setting means 3, a motor command value calculating means 4 for calculating the command value to the pulse motor for driving the throttle valve by inputting the output of the throttle opening setting means, and the motor command value calculating means. A throttle opening for a vehicle-mounted internal combustion engine, which includes a pulse motor 5 that receives an output and rotates, and a throttle valve 6 that is connected to the pulse motor and that opens and closes an engine intake passage according to the rotation. In the speed control device, the motor command value computing means inputs the output of the engine operating state detecting means to determine whether or not the motor is in a predetermined operating state requiring a slew-up operation, and is in the predetermined operating state. When it is determined that the target displacement amount has exceeded the displacement amount required to slew up and then slew down, it is configured to perform the slew-up process only when it is determined that the displacement amount is exceeded. .

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 2 is an overall schematic view of a throttle opening control device for an on-vehicle internal combustion engine according to the present invention. When the description is made with reference to FIG. 2, reference numeral 10 indicates the internal combustion engine. The internal combustion engine 10 has an intake passage 12
Air cleaner 14 attached to the tip side of
The intake air introduced through the intake valve enters the intake manifold 18 while the flow rate is adjusted by the throttle valve 6, receives fuel supply through the fuel injection valve 20, and enters the combustion chamber 24 through the intake port that opens and closes the intake valve 22. Inflow. The air-fuel mixture that has flowed in is ignited by a spark plug (not shown) and burns, drives the piston 26, and then enters the exhaust manifold 30 through an exhaust port opened and closed by an exhaust valve 28.
It is discharged to the outside of the engine through an exhaust pipe (not shown).

Further, an accelerator pedal 32 is arranged on the floor surface of the cab of the vehicle in which the internal combustion engine is mounted, and the pedal is urged to an idle position by a spring (not shown),
It rotates according to the stepping motion of the driving vehicle. As shown in the figure, the mechanical connection between the accelerator pedal and the throttle valve 6 is cut off, and instead, the pulse motor 5 is provided near the throttle valve. The pulse motor is connected to the valve shaft 6a of the throttle valve via a clutch mechanism and a reduction gear mechanism (not shown), and opens and closes the valve.
A return spring (not shown) is provided on the throttle valve shaft 6a to constantly urge the throttle valve in the fully closing direction. The opening of the throttle valve is detected by a throttle sensor 40 including a potentiometer and the like.

Further, an intake pressure sensor 42 for detecting the pressure of the intake air as an absolute pressure is provided at an appropriate position downstream of the throttle valve in the intake passage 12, and an intake temperature sensor 44 for detecting the temperature of the intake air is provided further downstream thereof. And an atmospheric pressure sensor 46 for detecting the atmospheric pressure is provided at an appropriate position upstream of the throttle valve. Further, an accelerator sensor 48, which is the above-mentioned accelerator pedal depression amount detecting means for detecting the depression amount (accelerator opening degree) of the accelerator pedal, is provided near the accelerator pedal, and a water temperature for detecting the cooling water temperature is provided at an appropriate position near the combustion chamber. A sensor 50 is provided, and a crank angle sensor 52 for detecting the crank angle of the engine is provided at an appropriate position in a distributor (not shown) or the like, while the vehicle travels at an appropriate position of a transmission (not shown). A vehicle speed sensor 54 for detecting the speed is provided. The outputs of these sensors are sent to the control unit 58.

Further, in this control device, an alternator (not shown)
ACG sensor 60 that detects the field current of the device, power steering switch 62 that detects the operation / non-operation of the power steering (not shown), and the operation / operation of the air conditioner (not shown).
An air conditioner switch 64 for detecting inactivity, a starter switch 66 for detecting activation / deactivation of a starter (not shown),
A range selector switch 70 for detecting a range position of a shift lever (not shown) and a shift position switch 72 for detecting a shift position (gear stage) (for example, by detecting a solenoid excitation signal of a mission control unit)
Is provided to send an output to the control unit, and a brake switch 74, a main switch 76, a set switch 78 and a resume switch 80 are also provided for automatic cruise control.

FIG. 3 shows the details of the control unit 58. In this unit, the analog output of the throttle sensor 40 or the like is input to a level conversion circuit 88, where it is converted to an appropriate level and then input to a microcomputer 90, The digital value is converted by the A / D conversion circuit 90a and temporarily stored in the RAM 90e. Further, the digital outputs of the crank angle sensor 52 and the like are waveform-shaped by the waveform shaping circuit 92 and input into the microcomputer through the input port 90b. In the microcomputer, the CP value 90c is obtained from these inputs in ROM90.
A control value is calculated as described below according to the program stored in d, and is sent to the output circuit 94 through the output port 90f, and the pulse motor 34 is driven through the drive circuit 96 including a transistor and the like. 6 is controlled to open and close. The drive circuit 96 is provided with a motor drive current from a battery power source 98, and is provided with a PWM control circuit 100 connected to an AC oscillator (not shown) to PWM-control the battery supply current to change the chopping duty. The frequency of the AC oscillator is fixed at 3 kHz, and the chopping duty is variable in the range of 75 to 95% according to the engine operating state, as will be described later. In the above configuration, the crank angle sensor 52 and the like excluding the accelerator sensor 48 correspond to the engine operating state detecting means, and the microcomputer 90 corresponds to the throttle opening setting means and the motor command value calculating means.

Next, the operation of the present control device will be described with reference to the flow chart of FIG. In addition, this program,
For example, it is repeated in a loop every 10 ms.

First, in S10, the previously calculated command value θ _CMDn−1 is output. This command value is the number of pulses indicating the amount of displacement,
In order to accurately calculate the current opening, the current opening is not output within the previous calculation cycle, but is temporarily stored and output at the beginning of the current calculation cycle. At the same time, the pulse rate command value P _OUTn-1 indicating the displacement speed and the chopping duty command value D _CHOPn-1 indicating the motor supply current amount are also output.

Next, in S12, the engine speed Ne, accelerator opening θ _AP , control parameters such as the starter switch signal are sequentially read and stored in the RAM 90e, and in S14, the accelerator opening and engine are referenced with reference to the map stored in the ROM 90d. Search for the reference opening θ _THM of the throttle valve from the rotation speed.

Subsequently, in S16, it is determined whether or not it is in the idle control range. This is judged from the starter switch signal, range selector signal, vehicle speed, intake pressure, throttle opening, engine speed, etc., 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, the process proceeds to S18, and the throttle opening θ _idle for idle control is appropriately determined. If it is determined in S16 that the engine is not in the idle control range, the process proceeds to S20 and the predetermined opening θ _idle-ref is set as the idle opening. This predetermined opening is, for example, 10 degrees (however, WOT = 84 degrees) which is the upper limit opening at the idle opening.

Then, it proceeds to S22 and determines whether or not it is in the automatic cruise control range. This is judged from the detection signals of the brake switch 74, the main switch 76 and the like. If it is determined that the vehicle is in the auto cruise control range, the program proceeds to S24, where the throttle opening θ _cru for auto cruise control is calculated so as to keep the vehicle speed at a constant value. The degree is zero.

FIG. 5 is a flow chart showing a subroutine for calculating the auto-cruise opening degree. Briefly explaining according to FIG. 5, the vehicle speed V exceeds the predetermined vehicle speed V0 of 20 km / h or more, and the brake switch is turned off. If the cruise is not already in progress and the set switch is on, the vehicle speed at that point is set as the vehicle speed V _SET (S24a to 24e), and the throttle opening is initially set to approach the opening corresponding to the set vehicle speed. The set amount is calculated, the flag F _THU is turned on, and the cruise opening θ _cru is calculated (S24f, 24g, 24h). In this case, the same applies when the set switch is turned off and the resume switch is turned on (S24i, 24j).

Then, in S28, the target opening θ _THO is calculated. This is performed by selecting the maximum value from the _openings calculated up to that point, that is, the reference opening θ _THM , the idle opening θ _idle, and the auto cruise opening θ _cru . By thus searching for the maximum value, for example, in an operating state in which the idle control range and the auto cruise control range overlap, it is possible to optimally control the throttle opening while making both controls compatible. Since the selected maximum value is indicated by the opening degree, it is converted into the number of pulses by dividing by the predetermined number (opening degree per pulse) in this step.

Subsequently, in S30, the previous throttle opening θ _THPn-1
(Pulse absolute value) Previous command value θ output in S10
_CMDn-1 is added to calculate the current opening, more accurately, the throttle opening θ _THPn currently being moved. Subsequently, in S32, the deviation between the current opening degree and the target value is calculated to determine the current motor command value θ _CMDn (pulse displacement amount).

Then, in S34, it is judged from the starter signal whether or not the engine is cranked. If it is determined to be cranking, the chopping duty D _CHOP0 for _cranking and the pulse rate P2 are searched for in S36, and the process proceeds to S38, where the chopping duty command value D _CHOP
= D _CHOP0 and pulse rate command value P _OUT = P2. The pulse number θ _CMDn is as calculated in S32.

The flow chart will now be described with reference to FIG. 6. In FIG. 6, the horizontal axis represents time and the vertical axis represents pulse rate and chopping duty. Therefore, when cranking the engine, the pulse rate is lowered to 400PPS (P _OUT = P2) and the chopping duty is also increased.
High duty around 95% (D _CHOP = D _CHOP0 ). That is, since the battery voltage is consumed by the starter and is decreasing, the pulse rate is decreased and the chopping duty is increased to obtain the required motor torque. In addition, the pulse rate is 100P in the state after the excessive cranking that shifts to the normal operating state thereafter.
Add PS and increase gradually, and gradually decrease chopping duty D _CHOP2 . After that, when the normal operating state is entered, the pulse rate P1 is set to 80 depending on the operating state.
The chopping duty D _CHOP1 is set appropriately in the vicinity of 0 _{PPS and} is variable according to the displacement amount. 7 to 9
The figure shows the pulse rate P1 during the normal operation state, the pulse rate P2 during the cranking, and the chopping duty D _CHOP1 during the normal operation state. As shown, the pulse rate P1 and chopping duty during normal operation
D _CHOP1 increases or decreases according to the number of pulses or the displacement angle (θ _CMDn above) (in the case of duty, the torque is increased when the displacement is large), and the pulse rate P2 during cranking is the engine speed Ne. Set to increase as you go up. These characteristic diagrams are ROM90d as table values
It is stored in.

Returning to the flow chart of FIG. 4 again, if it is determined in S34 that cranking is not performed, it is determined in S40 whether or not the pulse rate P2 during cranking has been searched, and if not, in S42 is appropriately performed. Predetermined value to set P20
Is P2. This is to include the case where the engine is started by pushing or the like.

Then, in S44, the pulse rate P during normal operation is set.
1, chopping duty D for after cranking
_CHOP2 , Chopping duty D during normal operation
Search for _CHOP1 . This is done by searching the ROM table for the characteristics shown in FIGS. 7 and 9. Although the chopping duty D _CHOP2 at the time of after-cranking is not shown, it is _assumed that the chopping duty D _CHOP2 has characteristics similar to those in FIG. 9 and is similarly stored as a table value.

Then, in S46, the predetermined value ΔP (100PPS described above) is added to the cranking pulse rate P2, and it is determined in S48 whether or not the pulse rate P1 in the normal operation state is exceeded. If it does not exceed S5, it is determined that it is still in a transient state.
At 0, the command values are D _CHOP = D _CHOP2 and P _OUT = P2. In this case, the pulse rate is gradually raised to prevent out-of-step of the motor as shown in FIG. 6, and the chopping duty is appropriately changed according to the number of pulses.

Subsequently, in S52, it is determined whether or not the command value θ _CMDn described above exceeds the number of steps C _THU required for slew-up and the number of steps C _THD required for slew-down. That is, the sixth
As shown in the figure, when the flag F _THU is turned on in the predetermined operation state, in the present embodiment, in the automatic cruise acceleration process of step 24g of the flow chart of FIG. Then, if it slews up in that case, it will inevitably slew down after that. Therefore, the command value (target step number) θ _{CMDn slews} up and down the number of steps C _This is because if it exceeds _THU + C _THD , for example, if it takes 3 steps to move up and down, it requires a rotation range of at least 6 steps. When the result in the flow chart of FIG. 4 is negative, the _{process proceeds} to S54, and the command values D _CHOP1 and P1 in the normal operation state are appropriately determined according to the number of pulses.

If it is determined in S52 that there is a required number of steps, the process proceeds to S56, in which it is determined whether slew-up is necessary. This is determined from the flag of S24g in the flow chart of FIG. 5, and when it is determined that the slew up is necessary, the process proceeds to S58, and the slew up interrupt permission is given. Since it is necessary to open and close the throttle opening quickly in the auto cruise acceleration processing, this interrupt is given the highest priority interrupt priority.

FIG. 10 is a flow chart showing a subroutine based on this slew-up interrupt processing. Explaining in accordance with this figure, first, at 58a, one reference pulse is output as shown in FIG. This is to show the criteria for starting the slew-up. Then, in S58b, the down counter C _UP and the timer T _UP are set to predetermined values C _THU and T _LO .
The counter value C _UP indicates how many pulses the slew-up ends, and the timer value T _UP determines how many ms the pulse interval is. Then, in S58c, the counter value is decremented by 1 and the timer value is used to obtain a predetermined amount Δt.
Is decremented and pulse output is started in S58d. Subsequently, in S58e, it is determined whether or not the counter value has reached zero, and if not, the flow returns to S58c to decrement and continue to output pulses. The number of output pulses is the counter value _CTHU , and the initial value of the pulse interval is the timer value.
Needless to say, the interval becomes shorter each time it is T _LO and loops. After it is confirmed that the counter value has reached zero and the setting pulse has been output, the process proceeds to S58f for interrupt termination processing, then proceeds to S58g to set the high-speed mode and at S58h sets the flag F _THU . Turns off and returns to the flow chart of FIG. As described above, in this interrupt processing, the normal control cycle of 10 ms is too late,
Processing is performed continuously.

Then, at the next program start-up, it is determined in S60 that the mode is the high speed mode, and the process proceeds to S62, until the target number of steps falls below the required slew-down required number C _THD , S64.
At, a pulse is output at a high pulse rate P _H.
In the high speed mode, as shown in FIG. 6, pulses are output at a high rate such as 1000 PPS. Also, the chopping duty is set to the increased value D _CHOPH .

When it is determined in S62 that the target number of steps is less than the required number of slew-down steps at the time of starting the program for several times, the process proceeds to S66, and the slew-down interrupt is permitted. This through-down interrupt subroutine will be described with reference to FIG. 11. After outputting the down start reference pulse in S66a, the counter value C _DWN is output in S66b.
Set value C that indicates how many pulses to finish the slew down
Along with setting _THD , an appropriate time value T _HI indicating the pulse interval is set in the timer T _HI and decremented each time the loop is reached until the set value is reached (S66c, 66d, 66e).
In this case, as shown in FIG. 6, the pulse interval gradually increases by Δ.
It will open every t. After reaching the set value, the slew-down interrupt process is centered and the high-speed mode is canceled (S66f, 66g). In this slew-down process, pulses are continuously output as in the slew-up process. For the chopping duty, use the duty D _CHOP1 during normal operation. When it is determined in S60 that the vehicle is not in the high speed mode in the flow chart of FIG. 4, the process proceeds to S54, and the command is given with the pulse rate and duty in the normal operation state.

Thus, in the above, the number of pulses θ _CMDn and pulse rate P
_{After OUT} and chopping duty D _CHOP are determined,
Except for through up / down interrupt processing
After being stored in RAM90e, at the next program startup, θ
_{It goes without saying that CMDn-1} , P _OUTn-1 , and D _CHOPn-1 are output at S10 at the beginning of the cycle.

As described above, in this embodiment, in the case of through-up,
It is determined whether the target displacement exceeds the displacement required for slew up and slew down, and if it exceeds, slew up processing is performed, so the pulse motor is accurately controlled to adjust the throttle opening. Therefore, the vehicle speed can be made to quickly follow the set value even in the automatic cruise control.

Although the starter signal is used to detect the cranking in the above embodiment, it may be determined from the battery voltage or the engine speed. Although the present invention has been described with respect to a mechanism in which the mechanical connection between the accelerator pedal and the throttle valve is completely disconnected, the present invention adds a pulse motor while leaving the mechanical connection such as the accelerator wire. It goes without saying that it is appropriate even if it is attached to the target.

(Effect of the invention) In the throttle opening control device for an on-vehicle internal combustion engine according to claim 1, the motor command value calculation means needs the slew-up operation of the motor by inputting the output of the engine operating state detection means. When it is determined whether or not the predetermined operation state is present, and when it is determined that the predetermined operation state is present, then it is determined whether or not the target displacement amount exceeds the displacement amount necessary for slewing down after slewing up. Since it is configured to perform the slew-up process only when it is determined that it exceeds the limit, it is possible to accurately control the throttle opening of the vehicle-mounted internal combustion engine through the pulse motor in the operating state that requires the slew-up while satisfying the real-time property. The advantage is that slew-up processing can be performed.

Further, in the apparatus according to the second aspect, the throttle opening setting means and the motor command value computing means are constituted by a microcomputer to perform the slew-up processing by interruption processing, and the interruption order has priority over other processing. Since it is configured as described above, there is an advantage that the control response and the followability can be further improved.

[Brief description of drawings]

FIG. 1 is a diagram corresponding to the claims of a 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 a control unit therein. A block diagram and FIG. 4 are flow charts showing the operation of the device.
FIG. 5 is a flow chart showing the auto-cruise subroutine in the flow chart of FIG. 4, and FIG.
FIG. 7 is an explanatory timing chart schematically showing the control of this device, FIG. 7 is an explanatory graph showing the characteristics of the pulse rate in the normal operation state used in this control, and FIG. 8 is the pulse rate during cranking. FIG. 9 is an explanatory graph showing the characteristics, FIG. 9 is an explanatory graph showing the characteristics of the chopping duty in the normal operation state, FIG. 10 is a flow chart showing the through-up interruption subroutine in the flow chart of FIG. 4, and FIG. Similarly, it is a flow chart showing a through-down interrupt subroutine. 1 ... Accelerator pedal depression amount detection means (accelerator sensor
48), 2 ... Engine operating state detecting means (crank angle sensor)
52 etc.), 3 ... Throttle opening setting means (micro computer 90), 4 ... Motor command value calculation means (micro computer 90), 5 ... Pulse motor, 6 ... Throttle valve, 10 ... Internal combustion Engine, 12 ... Intake passage, 32 ... Accelerator pedal, 40 ... Throttle sensor, 42 ... Intake pressure sensor, 44 ... 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, 66 …… Starter switch, 70 …… Range selector switch, 72 …… Shift position switch, 74 …… Brake switch, 76 …… AC main switch , 78 ... AC set switch, 80 ... AC resume switch, 82 ... Starter switch, 90 ... Micro computer, 98 ... Battery power supply, 100 ... PWM control circuit

Claims (2)

[Claims] Claims: 1. a. Accelerator pedal depression amount detecting means for detecting the depression amount of an accelerator pedal arranged on the floor of the vehicle driver's seat; b. Engine operating state detecting means for detecting the operating state of the engine; c. The engine Throttle opening setting means for inputting the outputs of the operating state detecting means and the accelerator pedal depression amount detecting means to set the opening of the throttle valve provided in the engine intake passage, d. Motor command value calculating means for calculating a command value to a pulse motor for inputting and driving a throttle valve, e. A pulse motor for rotating by inputting the output of the motor command value calculating means, and f. In the in-vehicle internal combustion engine throttle opening control device, which comprises a throttle valve that opens and closes the engine intake passage according to the rotation of the engine, the motor command value computing means is configured to output the engine operating state detecting means. By inputting force, it is determined whether or not the motor is in a predetermined operating state that requires a slew-up operation, and when it is determined that the motor is in the predetermined operating state, the target displacement amount then slews up and then slews down. A throttle opening control device for a vehicle-mounted internal combustion engine, characterized in that it is configured to determine whether or not a necessary displacement amount is exceeded, and to perform a slew-up process only when it is determined that the displacement amount is exceeded. 2. The throttle opening setting means and the motor command value calculation means are constituted by a microcomputer to perform the slew-up processing by interrupt processing, and the interrupt processing is prioritized over other processing. The throttle opening control device for an on-vehicle internal combustion engine according to claim 1.